Radio frequency communication technology has not only greatly improved public network service, but also developed a new technological route for indoor navigation service. However, there is a gap between the precision and accuracy of indoor navigation services provided by indoor navigation service and the expectation of the public. This study proposed a method for constructing a hybrid dual frequency received signal strength indicator (HDRF-RSSI) fingerprint library, which is different from the traditional RSSI fingerprint library constructing method in indoor space using 2.4G radio frequency (RF) under the same Wi-Fi infrastructure condition. The proposed method combined 2.4G RF and 5G RF on the same access point (AP) device to construct a HDRF-RSSI fingerprint library, thereby doubling the fingerprint dimension of each reference point (RP). Experimental results show that the feature discriminability of HDRF-RSSI fingerprinting is 18.1% higher than 2.4G RF RSSI fingerprinting. Moreover, the hybrid radio frequency fingerprinting model, training loss function, and location evaluation algorithm based on the machine learning method were designed, so as to avoid limitation that transmission point (TP) and AP must be visible in the positioning method. In order to verify the effect of the proposed HDRF-RSSI fingerprint library construction method and the location evaluation algorithm, dual RF RSSI fingerprint data was collected to construct a fingerprint library in the experimental scene, which was trained using the proposed method. Several comparative experiments were designed to compare the positioning performance indicators such as precision and accuracy. Experimental results demonstrate that compared with the existing machine learning method based on Wi-Fi 2.4G RF RSSI fingerprint, the machine learning method combining Wi-Fi 5G RF RSSI vector and the original 2.4G RF RSSI vector can effectively improve the precision and accuracy of indoor positioning of the smart phone. At present, wireless networks and mobile smart terminals play crucial roles in human life. With the help of various smart terminals and derivative application services, humans have gradually entered a new era of mobile Internet information. In particular, the deep integration of mobile smart terminals and location-based services has greatly affected and changed traditional human lifestyles in all aspects. As a key node that connects the online and offline worlds, location based services (LBSs) play a key role in practical applications.The study of location-based service technology started in the 1990s ,3, indusIn outdoor space, the construction and industrial application of the four major satellite positioning systems has been realized through unremitting efforts of various countries. The positioning accuracy of the global navigation satellite system can meet the location-based service demand in the military and civil fields . Due to Scholars have carried out various studies of indoor positioning technology. The theoretical study and product development of mainstream positioning technology based on infrared ray , ultrasoBased on the high applicability of the fingerprint library matching method, this paper designs the framework of a fingerprint positioning method based on hybrid dual frequency received signal strength indicator (HDRF-RSSI) according to the basic principles of the fingerprint library matching method. The dual radio (2.4G and 5G) broadcast characteristics of Wi-Fi AP networking are used to collect the dual radio RSSI characteristics of the reference node during the offline phase to fuse the dual radio characteristics. Compared with the single RF fingerprint database construction method, the hybrid dual RF RSSI fingerprint library construction method designed in this paper enhances the fingerprint density. In addition, a neural network processing method is introduced in this paper. The dual radio frequency RSSI fingerprint is used as the neural network input. The output is defined as the distance of the node to be located from the origin of the scene. The impact of non-visual conditions on the positioning is assessed.In 1994, American scholar Schilit first put forward three major goals of location service: where you are , who you are with , and nearby resources (information inquiry) . ConsideAccording to the existing literature, fingerprint localization based on RSSI has achieved abundant results ,29, but At present, the representative classification method divides location estimation algorithms based on fingerprint library positioning technology into deterministic algorithms ,26 and pIn the probabilistic algorithm research with the gradual maturity of artificial intelligence technology, machine learning and deep learning technology have made great progress in indoor positioning. In deep learning  and machThe above analysis reveals that to improve the accuracy and precision of indoor locations, the location technology or methods based on the fingerprint database focus on the following three aspects. First, how to make the reference point fingerprint database established in the offline phase cover the signal change characteristics of the reference point to enhance the fingerprint density and uniqueness. Second, how to effectively express the RSSI vector. Since RSSI only has space for semaphore changes and changes with time, the fingerprint vector established just using the RSSI value cannot cover its changes in the time domain, leading to deviations in location estimation. Third, how to estimate node location when the location node and RF transmitting node are invisible. The basic principle of fingerprint positioning is to reflect the attenuation response of a signal in radio frequency propagation in a spatial medium according to the change in the RSSI value over a spatial distance and to estimate the change in distance based on the inverse signal difference. However, the radio frequency should be propagated in the same medium, which is a prerequisite. If the radio frequency propagates in multiple media or the multipath effect is considered, there will be large errors in the signal difference, greatly decreasing the accuracy of the position estimation.The remaining sections of this article are as follows. In Herein, the framework of an hybrid dual frequency received (HDRF) RSSI fingerprint location method is rationally designed, and a 2.4G and 5G dual radio frequency RSSI fingerprint database is constructed based on the broadcast characteristics of the Wi-Fi dual radio frequency (2.4G and 5G). To deeply understand the fingerprint characteristics of the 2.4G and 5G HDRF RSSI fingerprint database, the noise distribution of the Wi-Fi 2.4G and 5G RSSI and the distinguishability of RSSI vector features at adjacent locations are compared in this section. According to the experimental results, the RSSI fingerprint database constructed with the 2.4G and 5G dual radio frequency improves the density and distinguishability of fingerprints compared with that of the 2.4G radio frequency, which can provide more accurate data support for the subsequent location evaluation.Because the 2.4G frequency band has universal applications and is a license-free frequency, there is a lack of uniformity in indoor coverage, leading to more interference in the 2.4G band frequency , as showTo address the problems of few frequency points and mutual interference in the 2.4G frequency band, 5 GHz wireless communication technology has been employed. The 5 GHz frequency band is an open ISM frequency band with a higher frequency than 2.4 GHz. Recently, this technology entered the product development stage. Moreover, it complies with international standards such as IEEE 802.11a, FCC Part 15, ETSI EN 301 489, ETSI EN 301 893, EN 50385, and EN 60950. IEEE 802.11a works in the 5G band with a frequency range of 5.725G–550 GHz, a total of 125 M of bandwidth, and 20 MHz per channel. According to the free space signal loss model, different RSSI should be derived at two different locations for the same AP point, and the change in RSSI observations is proportional to the logarithm of the distance in an ideal situation . HoweverTo verify the distinguishability of 2.4G and 5G HDRF RSSI fingerprints for adjacent location fingerprints compared to traditional 2.4G radio frequency RSSI fingerprints, two experiments with the same sampling scenario, number of APs, collection equipment, and RP positions are designed in this study.In the first experiment, there are 2 APs and 4 pairs of adjacent distance reference points. In addition, the distance between each pair of reference points is 2, 4, 6, and 10 m, respectively. The fingerprint for each reference point consists of 2D 2.4G-RSSI. A Huawei Mate 30 mobile phone is used for the 2.4G-RSSI fingerprint collection, and 150 sets of fingerprints are collected for each reference point. In the second experiment, the original 2.4G-RSSI vector was fused with the 5G-RSSI vector of the same AP. In this way, the reference point fingerprint was constructed using four-dimensional fingerprint data. Similarly, a 150 fingerprint set was collected for each reference point. Based on the above two experiments, we find that 2.4G and 5G HDRF RSSI fingerprints not only enhance the density of fingerprint vectors but also decrease the overlap rate of clustering intervals of fingerprint data at adjacent locations under the same number of APs. The overlap rate is decreased by 18.1% on average, with the highest decrease being 20.4%. The stronger the distinguishability of the RSSI vectors at any two adjacent positions is, the less likely the position estimation algorithm to make an incorrect estimation, meaning higher location accuracy and precision.There are two stages in the HDRF RSSI fingerprint location process, including the offline stage and online stage. In the offline phase, it is necessary to set a number of reference positioning points (RPs) first and then use a smartphone to collect the dual radio frequency RSSI. Then, the collected RSSI signals are subject to pre-processing, and a dual-frequency RSSI fingerprint model is established. Machine learning methods are used to train the fused RSSI fingerprints. Finally, a fingerprint prediction model is generated. In the online stage, the RSSI fingerprints at the location test points (TPs) are collected and input into the fingerprint prediction model. The physical distance between the test point and the original point is set as the output. The schematic diagram is shown in At present, 2.4G and 5G networks can support almost all smartphones. Therefore, mobile APP software is employed to obtain the WI-FI-AP information around the reference point. The RF RSSI data of the reference point has three parts, including the 2.4G and 5G RF signal values and data labels. 2.4G and 5G RF signals are the input of the subsequent hybrid RSSI fingerprint training model, and the data label is the distance from the reference point to the original point, which is described as follows:Assume the coordinates of i refers to the i-th reference point, j is the j-th characteristic fingerprint datum at the i-th reference point, and n represents the number of dual radio frequency APs. Thus, hybrid RF multi-feature data over multiple time periods at the reference point can be obtained.The received signal strength indicator (RSSI) is defined as the received AP signal strength indicator, which is mainly used to evaluate the link quality. The RSSI value is an interval indicator relative to the highest and lowest values. During the data collection process, the sampling frequency is set to 1 Hz, the period of each reference point is 5 min, and 300 samples in total are collected. According to Formula (2), the original data are merged to reflect the characteristics within the sampling period. Afterward, the collected RSSI data are regularized to retain the valid data and eliminate the invalid data. The data are processed based on Equation (3), and each RSSI value is 0 or 1:The hybrid RSSI fingerprint classification model is the CIFAR-10 model framework based on the image classification , which cThe commonly used network structure of the Cifar-10 model consists of several volumes, pooling layers, and fully connected layers, as shown in i-th distance distribution classification. Hence, under a given probability quality function In this study, each dual RF RSSI data sample for RP was transformed into a 32 * 32 image as input to the training model. In the model output, the classification output of the CIFAR-10 MODEL 10 was used to calculate the probability ratio of the distance from the observation point to the origin. The CIFAR-10 model was employed to predict the probability distribution of the distance from the unknown node to the coordinate origin. The empirical probability quality function P stands for the given true distance distribution:The standard deviation score for the distance distribution is expressed as follows:In Among the various machine learning classification tasks, the Softmax cross-entropy is widely used as the training loss. o et al.  suggesteIn this study, the distance from the TP to the set original point is predicted. The maximum distance  follows :(8)EMD .The learning rates of the convolutional layer and the last fully connected layer were set as 3 × 10The CNN structure is composed of three volume layers, three pooling layers, two fully connected layers, and one Softmax layer. In order to calculate floating point operations (FLOPs), this section deduces the formula for different layers . Table 1i is the ith volume layer. MAC (multiplication and addition) operand of a single-step convolution operation is as below:For a volume layer, the size of its input channel is The first item is the multiplication operand of the single convolution, and the second item is the addition operand. Considering the bias item, one item is added in Equation (9). The total number of convolution operations per convolution layer can be calculated from the dimension of the output characteristic graph, namely, The operand in the fully connected layer depends on the input feature dimension Because there is no parameter in the pooling layer and the activation function layer, the operand is linearly related to the number of elements contained in the input tensor. The dimension of input tensor is n = 3 indicates that there are three convolution layers in the model. The formula for the fully connected layer is as below:n = 3 indicates that there are three fully connected layers in the model. The formula for the pooling layer and the activation function layer is as follows:The FLOPs of the model is obtained by adding the operand of each layer, and the convolution layer formula can be simplified to Equation (13):There are three pooling layers and four relu layers. The total FLOPs are expressed in Equation (16):The operand of each layer and the total FLOPs are summarized in The location evaluation algorithm based on hybrid dual RF RSSI mainly consists of two parts: the offline part and the online part, as shown in At the offline stage, multiple reference points (RP) are set, and dual RF RSSI is collected using smart phones. The collected RSSI signals are preprocessed, a dual RF RSSI fingerprint model is established, and the machine learning method is used to train the fused RSSI fingerprint. Finally, the fingerprint prediction model is generated. In the online stage, it is necessary to predict the physical coordinates of the TP point. The hybrid RSSI RF fingerprint collected at the TP point should be input into the hybrid RSSI fingerprint classification model to obtain the average distribution score of the point fingerprint:Then, The schematic diagram of the position estimation algorithm in the online stage is displayed in RP is defined as the reference node that is the closest to the TP, and its coordinates are  are planned using a 1 × 1 m grid, and the collection area contains 11 rooms including corridors and offices.The experiment was conducted on the third floor of the College of Computer Science and Technology, Jilin University, Changchun, Jilin, China. The building area covers 2600 mThe experimental results demonstrate that one RP can receive the Wi-Fi RF signals of 5~7 different APs. During the trial phase, we performed a total of 10 position evaluation tests by randomly selecting 20 TPs each time, collecting the dual RF RSSI for each TP to form a dual RF RSSI vector, inputting these data into the CIFAR-10 position evaluation model, and finally obtaining the physical coordinates of the TPs. It is observed in the experiment that the output process of the physical coordinates of the test node can be output in real time. After 10 position evaluation tests, we average the mean, standard deviation, root mean square (RMS) value, and the maximum error of the evaluation position for each evaluation position.To evaluate the performance of the HDRF location method, the HDRF RSSI fingerprint location method was compared with several traditional 2.4G Wi-Fi fingerprint indoor location algorithms using the same data set, which include the KNN , the supAccording to the above data, when the HDRF RSSI fingerprint and 2.4G-RSSI fingerprint are used, the average errors of the proposed location method are 1.7 and 2.4 m, respectively, with an improvement rate of 29.16%. When the 2.4G-RSSI fingerprint is used, the location errors of the proposed location method, the SVM (linear kernel), the KNN (k = 5), and the random forest location methods are 2.4, 2.8, 3.2, and 4 m, respectively. The errors of the proposed location method are improved by 39.3%, 42.85%, and 57.5% compared to those of the SVM, the KNN, and the random forest location methods, respectively. When the location error is 2.5, the location accuracies of the HDRF RSSI, 2.4G-RSSI, SVM (linear kernel), KNN (k = 5), and random forest are 78.2%, 62.3%, 51.7%, 23.4%, and 16.3%, respectively. When the location error is 3.5 m, the location accuracies of the algorithms are 90.6%, 73.2%, 68.3%, 69.2%, and 37.9%, respectively. The above results indicate that the HDRF RSSI fingerprint has the ability to enhance the location accuracy and location error compared with the traditional 2.4G-RSSI fingerprint method. Additionally, the proposed location method achieves a smaller average location error and higher location accuracy compared to the abovementioned algorithms. For the KNN algorithms that are compared, in order to avoid a K value selection that couples numerical associations, we compare the K= 3 and 11 CDF curves. It can be seen that the K that is selected will have a significant impact on the results of the algorithm. When K = 11, the positioning accuracy is poorer mainly because of the large area when forecasting the training instances, which can cause too much predictor interference due to too few similar training instances, and lower the KNN positioning accuracy. When K = 3, due to the smaller K value selection, the number of equivalent examples in the training and the smaller forecast area, the forecast result is often sensitive near the reference point. If the instance point of the nearest neighbor happens to be noise, the prediction will be wrong; thus, choosing the right K value will improve the accuracy of KNN positioning.When comparing the SVM location algorithms, the selection of the kernel function is confined by Mercer’s theorem, which hinders the further optimization of the SVM support vector regression effect and thus any further improvement of the location accuracy. When using the random forest location algorithm, the proposed fingerprint dimension of the fingerprint database is higher than the traditional 2.4G fingerprint. Overfitting may occur when using the random forest algorithm, which results in relatively low location accuracy. The positioning features are not obvious due to the relatively sparse 2.4G RF RSSI vector fingerprint features in some special areas. The distinguishability of a fingerprint near the reference point is weak, and the possibility of making the wrong estimation using the location algorithm is high, which reduces the location accuracy. Due to the existence of the Wi-Fi network communication dual radio frequency (2.4G and 5G) in the proposed HDRF RSSI fingerprint location method, the density of a fingerprint at the reference point was enhanced compared with the single radio frequency fingerprint database construction method. Meanwhile, a neural network handling method was also introduced. The hybrid radio frequency RSSI data were taken as the input of the neural network, and the distance from the node to be located to the original point was set as the output. The effect of visible and non-visual conditions on the location evaluation during the conversion of the logical distance and physical distance was solved in the positioning process of the traditional RSSI model, which contributes to the high location accuracy and precision. In the above As an important branch of the indoor location method, the Wi-Fi-based radio frequency RSSI fingerprint matching and location technology and probabilistic location evaluation method have been favored by Chinese and foreign scholars. In recent years, it has become the study direction and hotspot in the field of indoor positioning. This study focuses on the application of probabilistic location evaluation in Wi-Fi radio RSSI fingerprint library positioning. First, the sparsity of the traditional RP node 2.4G-RSSI fingerprint characteristics was solved. By combing 5G RF and original 2.4G radio frequency, the RP fingerprint dimension was doubled, and the distinguishability of the RP fingerprint characteristics was increased by 18.1%. Second, considering the positioning accuracy error in the conversion of logical distance and physical distance under non visual condition between TP and AP in the location evaluation stage, a hybrid dual radio frequency fingerprint model based on the machine learning method, training loss function, and location estimation algorithm were proposed. The clustering problem in the traditional location evaluation algorithm was transformed into a machine learning classification problem. Finally, a comparative experiment of different location algorithms was designed. Experimental results show that the proposed hybrid dual radio RSSI fingerprint construction method and location evaluation algorithm can effectively improve the precision and accuracy of smart phone localization in the indoor location. The accuracy of the proposed positioning method is 1.7 m. When the positioning error is 2.5 m, the positioning accuracy is 78.2%.It should be noted that there are many factors influencing the precision and accuracy of indoor positioning based on RF communication technology, such as the complexity of spatial structure, reflection, refraction, interference, and shadow fading effect of RF signal, as well as the RF RSSI fingerprint acquisition method. Both the deterministic location method and probabilistic location method have their advantages. In future study, the universality and practicability of the proposed indoor location method will be further enhanced combined with the deterministic location method.


The axial compressive behaviour of an innovative type of square concrete filled steel tube (CFST) column to reinforced concrete (RC) beam joint was experimentally investigated in this paper. The innovative joint was designed such that (i) the steel tubes of the CFST columns were completely interrupted in the joint region, (ii) the longitudinal reinforcements from the RC beams could easily pass through the joint area and (iii) a reinforcement cage, including a series of reinforcement meshes and radial stirrups, was arranged in the joint area to strengthen the mechanical performance of the joint. A two-stage experimental study was conducted to investigate the behaviour of the innovative joint under axial compression loads, where the first stage of the tests included three full-scale innovative joint specimens subjected to axial compression to assess the feasibility of the joint detailing and propose measures to further improve its axial compressive behaviour, and the second stage of the tests involved 14 innovative joint specimens with the improved detailing to study the effect of the geometric size of the joint, concrete strength and volume ratio of the steel meshes on the bearing strengths of the joints. It was generally found from the experiments that (i) the innovative joint is capable of achieving the design criterion of the ‘strong joint-weak member’ with appropriate designs, and (ii) by decreasing the height factor and increasing the volume ratio of the steel meshes, the axial compressive strengths of the joints significantly increased, while the increase of the length factor is advantageous but limited to the resistances of the joint specimens. Because of the lack of existing design methods for the innovative joints, new design expressions were proposed to calculate the axial compression resistances of the innovative joints subjected to bearing loads, with the local compression effect, the confinement effect provided by the multi-layers of steel meshes and the height effect of concrete considered. It was found that the proposed design methods were capable of providing accurate and safe resistance predictions for the innovative joints. The concrete-filled steel tube (CFST) structure is a high-efficiency solution for high-rise buildings and bridges due to its high bearing capacity, excellent ductility and great energy dissipation capacity . In CFSTRecently, through-beam joints connecting the CFST columns and RC beams have attracted the interest of researchers because of their simple detailing in the joint area, with a brief review of the recently developed through-beam joints summarised herein. Nie et al.  and Bai Because of the lack of existing experimental investigation on the compressive behaviour of innovative joints, a two-stage experimental study was first conducted to investigate the compressive behaviour of the innovative joint subjected to bearing loads, where the first stage of the tests included three full-scale innovative joint specimens to assess the feasibility of the joint detailing and propose measures to further improve the axial compressive behaviour of the joint, and the second stage of the tests involved 14 innovative joint specimens with the improved detailing to further study the effects of the geometric size of the joint, concrete strength and volume ratio of the steel meshes on the bearing strengths of the joints. Because of the lack of existing design methods for innovative joint, new design expressions for the bearing strengths of the innovative joints were developed and validated by the experimental results.The Series I axial compression tests included three geometrically identical full-scale specimens, namely SC1, SC2, and SC3, and were designed with various rebar diameters of the steel meshes in the joints. Each specimen included the upper and lower CFST columns and the joint, as shown in During the fabrication of the specimens, four concrete cube specimens were respectively reserved when casting the concrete of the lower CFST column, joint area and upper CFST column. Compression tests were conducted on the concrete cubes to derive their cubic strengths at the day of the column tests, with the average cubic compressive strength of each part of the specimen reported in The Changchun CSS-254 15 MN universal testing machine was employed to apply axial compression force to the specimens, with the test setup shown in All the specimens exhibited similar overall behaviour under axial compression during the tests, as summarised below. The first vertical crack was found on the side surface of the joint when the upper load reached 44~57% of the peak loads. With the load increased, the horizontal cracks occurred and gradually crossed the first vertical crack. The dilation and local buckling of the steel tubes were observed when the specimens reached their peak loads, while the concrete in the joint area remained intact without series spalling, which indicates that the specimens were failed by the local buckling of outer steel tubes of the CFST columns and thus satisfied the design criterion of the ‘strong joint-weak member’. The crack patterns on each side surface of the joint at failure are shown in Nu , the first crack was found at the middle of the side surface of the joint in the vertical direction. As the load increased to about 50% of Nu, the vertical crack developed with a maximum width of about 0.1 mm, and a short horizontal crack occurred on the side surface of the concrete at the same time. At about 70% of Nu, the maximum widths of the vertical and horizontal cracks on the side surface of the joint reached 0.25 mm and 0.15 mm, respectively. When the specimen reached its maximum load Nu, dilation and local buckling of the steel tubes of the CFST columns were observed. At the post-peak loading stage, the steel tubes of the CFST columns continued to dilate with the load capacity of the specimen gradually dropped to about 85% Nu.Taken specimen SC2 as an example to illustrate the experimental observation in detail, when the load reached about 45% of Ncr and the peak loads Nu for all specimens are listed in Ncr for SC1 is 1.13 and 1.18 times than those of SC2 and SC3 respectively, which indicates that the crack resistance of the joint is enhanced by improving the volume ratio of steel meshes in the joint (ρv). However, the ultimate axial compressive strength of SC1 is smaller than those of SC2 and SC3. It may be attributed to the discreteness of concrete material in the CFST columns, as all specimens eventually failed in the CFST columns.The axial load-deformation curves of the three specimens are shown in Nu when the first crack appeared, the strains developed dramatically and subsequently reached the yield strains at the peak loads. It was also found that as the volume ratio of the steel meshes in the joint decreases, the strain values corresponding to the peak loads increase, which exhibits more adverse elongation deformation of the steel meshes.The load-strain relationships of the steel meshes in all specimens are similar, as According to the experimental results and analysis of the Series I tests, it can be concluded that the axial load carrying capacity of the joint can be higher than those of the CFST columns by proper design, which verifies the feasibility of the innovative joint. However, the multi-layers of steel meshes in the joint is difficult to rig up because of the lack of efficient supports. Moreover, square CFST columns are extensively used as structural members due to aesthetic consideration. In order to improve the construction operability of the joints, an improved joint detailing specifically for square CFST columns is developed. In the improved joint detailing, the stirrups were added in and arranged radially around the multi-layers of steel meshes to assemble into a steel cage, as shown in ρv), the dimension of the joint and the concrete strength. The test specimens were named based on the following parameters, where C20 and C30 represent the cubic compressive strengths of the concretes are 15.34 MPa and 32.96 MPa respectively, L1, L2 and L3 refer to α = 1.6, 1.8 and 2.0 respectively; H1, H2 and H3 indicate β = 0.6, 0.8 and 1.0 respectively; and S1, S2 and S3 represent ρv = 1.0%, 1.5% and 2.0% respectively.In order to study the axial compressive behaviour of the innovative joints with the improved detailing of the steel meshes, the tests of Series II were conducted subsequently. A total of 14 full-scale specimens were designed and fabricated. The details of the joint specimens are shown in a of 300 mm. In order to examine the actual bearing strengths of the joints, the upper and bottom CFST columns adopted in the Series I tests were removed and replaced by a pair of thick steel plates, with their cross-section dimensions identical with the local compression area. A total of 3 (β = 0.6) or 4 (β = 0.8 and 1.0) layers of steel meshes were horizontally and symmetrically arranged in the joint area. The diameters of the rebars in each steel mesh were determined according to the volume ratio of the steel meshes in the joint (ρv) and the joint volume, with the detailed steel bars adopted in each layer of the steel mesh listed in The specimens were all loaded concentrically. The compression zones on surfaces of the joints were square with the side length The test setup for the Series II tests is shown in Ncr, the loads when the maximum crack width developed to 0.2 mm N0.2 and the loads when the maximum crack width developed to 0.3 mm N0.3. It can be concluded that all the specimens had similar performance during the tests, with cracking of the concrete, yielding of the steel meshes and eventual spalling and crushing of the concrete. At the ultimate loads, several vertical penetrating cracks occurred on the surface of the joint. However, the distributions of the horizontal cracks were different with various height factor β. Accordingly, three different crack patterns  on the surface of the specimens can be classified according to the distributions of the horizontal cracks, as shown in β increases from 0.6 to 1.0, the horizontal cracks begin to generate, and the number of horizontal penetrating cracks gradually rises. The crack pattern modes of all the 14 specimens are summarised in β of 0.6 were categorised as the crack pattern of Mode I. Taking specimen C30-L2-H1-S2 as an example to describe the experimental observation in detail, the first vertical crack appeared when the upper load reached 800 kN. The crack extended gradually and became a penetrating crack when the load reached 1200 kN. The steel meshes started to reach the yield strains as the load increased to about 4000 kN. After that, the specimen reached its maximum load-carrying capacity of 7800 kN. During the post-peak loading stage, the concretes began to spall and crush. The test was terminated when the bearing capacity of the specimen declined to 85% of its peak load. Regarding the crack pattern of Mode I, several vertical penetrating cracks can be found on the surfaces of the joint. The horizontal cracks may appear on the surfaces of the joint, but they were not penetrating . The speβ of 0.8 were categorised as the crack pattern of Mode II. Taking specimen C30-L2-H2-S2 as an example to describe the experimental observation in detail, the first vertical crack occurred at the load of 1200 kN and developed into a penetrating crack at the load of 1500 kN. When the upper load reached 3300 kN, several horizontal cracks began to appear and gradually developed into a penetrating crack at the load of 5000 kN. At the load of about 6500 kN, the specimen reached its maximum load-carrying capacity. The test was ended when the upper load dropped to 85% of its peak load.Regarding the crack pattern of Mode II, several vertical penetrating cracks and a main horizontal penetrating crack can be observed on each side surface of the joint see . The speβ of 1.0 were categorised as the crack pattern of Mode III. Taking specimen C30-L2-H3-S2 as an example to describe the experimental observation in detail, the first vertical crack appeared at the load of 900 kN. When the upper load reached 2700 kN, the first horizontal crack occurred. After that, several horizontal cracks could be observed on each side surface of the specimen and eventually generated two main horizontal penetrating cracks when the load increased to 5000 kN. The specimen reached its load-carrying capacity of 5550 kN. The test was terminated when the load dropped to 85% of its peak load.Regarding the crack pattern of Mode III, several vertical penetrating cracks and more than one horizontal penetrating cracks could be found on each side surface of the specimen see . The speThe comparison of failure modes between different concrete strengths is displayed in N) versus longitudinal displacement (Δ) curves for typical specimen series are plotted in α. It can be observed that the curves are quite close to each other. As shown in α is advantageous but limited to the peak loads of the specimens in this experiment. β are 0.6, 0.8 and 1.0 for specimens C30-L2-H1-S2, C30-L2-H2-S2 and C30-L2-H3-S2, respectively. As shown in β is a significant parameter affecting the behaviour of the specimen. The increase of β could evidently reduce the initial stiffnesses and the peak loads of the specimens. ρv for specimens C30-L2-H2-S1, C30-L2-H2-S2 and C30-L2-H2-S3 are 1.0%, 1.5% and 2.0%, respectively. As shown in ρv could significantly increase the peak strengths of the specimens. However, the strengthen efforts could be weakening once ρv is larger than 1.5%. In addition, the effect of ρv on initial stiffness of the specimen is limited.The load  the resistances of the joints were sustained or declined slowly after the peak loads, indicating excellent ductility of the joints when subjected to bearing loads, and (ii) with the decrease of height factor Because of the lack of existing guidelines for the design of the innovative joints, a theoretical investigation was conducted in this section to determine the axial compression resistances of the innovative joints subjected to bearing loads, based on the test observations and analysis in Nplain is the design bearing compression of unconfined concrete; fc is the characteristic compressive cylinder strength of unconfined concrete; A1 is the loaded area; A2 is the area of the lower base of the largest frustum of a pyramid, cone or tapered wedge contained wholly within the support and having its upper base equal to the loaded area.Several experimental studies have been conducted to investigate the resistances of plain concretes under local compression ,20,21,22It is certified from the experimental results that the ductility and the bearing strength of concrete improved due to the confinement from the multi-layers of steel meshes. However, the advantage contribution of the confinement effect on the concrete strength is not included in Equation (1), as set out in ACI 318-08 , which wlf is the lateral pressure provided by the transverse reinforcements and assumed to be uniformly distributed in the concrete core; fy is the yield strength of the reinforcing bars; ke is the confinement effectiveness coefficient, which takes into account the reduction in the confinement effect due to the spalling off of the cover concrete. Although vertical and horizontal cracks were observed on the side surfaces of the joint specimens, the concrete in the loaded area remained intact in the experiments. Therefore, the reduction in the confinement effect due to the spalling of the cover concrete is neglected, with the confinement effectiveness coefficient ke = 1, leading to the expression to calculate the lateral pressure given by Equation (4).Given that the amount of the reinforcements in both directions of the multi-layers of steel meshes are approximately the same, the effective lateral confining pressure tion (3) , where fβ is a critical factor affecting the ultimate strength of the joint [h/d ratio and displayed in d is the width of the local compression zone. As shown in h/d ratio results in a downtrend of Existing experimental results have demonstrated that the height factor he joint ,20. Withhe joint  and Yi ehe joint . The lath/d = 2, which represents the frictional force between the loading plates and specimens is neglected if the height-to-width ratios of the concrete specimens are greater than 2. According to Equations (2) and (5), when h/d = 1, the value of In Equation (5), it is discovered that specimen .Through considering the local compression effect, the confinement effect provided by the multi-layers of steel meshes and the height effect of concrete, the formulas for calculating the compressive resistances of the joints are summarised in Equations (6)–(8).Nu and the predicted results Ncal, as listed in Ncal for the joint specimens in Series I are higher than the corresponding experimental counterparts, which could be attributed to the fact that all the specimens in Series I failed by the CFST columns, and the ultimate strengths of the joints were higher than those of the CFST columns. For Series II, the resistance predictions derived by Equations (6)–(8) are in good agreement with the experimental ones for normal strength concrete (C30), with a mean value and standard deviation of Ncal/Nu equal to 1.038 and 0.100, respectively. However, the ultimate strengths were overestimated for the specimen series with low strength concrete (C20). It may be because the outer concrete of the specimens with lower concrete strength was prematurely spalled and crushed when the specimens were reaching their ultimate strengths, which would weaken the favourable effect of local compression.Assessment of the accuracy of the new proposal was then conducted, through the comparisons between the experimental ultimate strengths Therefore, the calculation model for the ultimate strengths of the joints subjected to bearing loads for practical engineering design is recommended herein. The confinement effect provided by the multi-layers of steel meshes and the height effect of concrete are considered in the model, while the effect of local compression is neglected because of its uncertainty, leading to the final formulations for the design of the ultimate strengths of the square joints given by Equations (9) and (10).The axial compressive behaviour of square through-beam joint between CFST column and RC beams with multi-layers of steel meshes was experimentally and theoretically investigated in this paper. The following conclusions can be drawn based on the results of this study.The first stage of the tests included three full-scale innovative joint specimens, indicating that the innovative joint is capable of achieving the design criterion of the ‘strong joint-weak member’ with appropriate designs. β of the joint specimens from 0.6 to 1.0, the axial compression strengths of the joints significantly decreased with a maximum reduction ratio in strength equal to 28.9%. The increase of the volume ratio of the steel meshes in the joint ρv is advantageous for the axial compression strengths of the joints. As ρv increased from 1.0 to 2.0, the axial compression strengths of the joints increased by 26.4% and 15.2% for the specimens with concrete grades of C20 and C30, respectively. The increase of the length factor α is advantageous but limited to the peak loads of the specimens. The second stage of the tests involved 14 innovative joint specimens with the improved detailing to study the effects of the geometric size of the joint, concrete strength and volume ratio of the steel meshes on the bearing strengths of the joints. It is shown that by increasing the height factor Because of the lack of existing design methods for the innovative joints, new design expressions were proposed to calculate the axial compression resistances of the innovative joints subjected to bearing loads, with the local compression effect, the confinement effect provided by the multi-layers of steel meshes and the height effect of the concrete considered. The strength predictions of the joints are in good agreement with the experimental ones for normal strength concrete. Through the discussion of the calculated results, recommended formulations for the design of the joints were proposed, which is capable of providing accurate and safe resistance predictions for the innovative joints. However, because of the limited range of variables chosen for the specimens in the tests, extensive applications of the proposed calculation method should be verified by further experimental researches.


Pinus sylvestris L.) has a significant impact on the physical and mechanical properties of the wood from which they are made. Only butt-end logs (log type O) allows for the production of high-quality timber elements. The pine timber that was evaluated in this paper had a high density of about 570 kg/m3 and a high percentage of timber items were assigned to class C24 and higher (above 50%). The adopted horizontal model of evaluation of the modulus of elasticity gave similar results to those obtained in an evaluation according to the EN-408.The study assessed the quality of pine lumber by marking the modulus of elasticity in the horizontal system. The research material was a plank with the following dimensions: 137 mm wide × 39.50 mm thick × 3485 mm long. The pine wood was obtained by sawing timber in the form of logs with round cross sections and originating from the Forest Division Olesno . Each long log was sawn to provide four logs of about 3.5 m, which were marked as butt-end logs (O), middle logs (S)—2 items, and top logs (W). The origin of the logs from the trunk ( Pinus sylvestris L.) originating from Polish forests [To improve the applicability of timber in the construction industry, manufacturers are required to provide components with as low a number of defects as possible. Such components are made both as solid and glued semi-products ,2,3. It  forests ,7,8,9,10 forests ,12,13,14The complete and practical application of pine wood for the manufacturing of glued components requires timber strength grading ,17,18,19The wood of the pine tree is valued for its high availability, good strength characteristics, and high productivity of each long log, which is due to the specific anatomical characteristics of this species. As previous studies have shown, not only the geographical region, but also the location of the log in a given tree zone influences the quality of the sawn timber harvested. It was shown that the middle and butt logs had a lower number of defects. Moreover, the proportion of raw material without defects increases as the distance from the core increases. The occurrence of a large number of knots in the Polish raw material is considered a negative quality characteristic. It is known that the number and intensity of defects affects the static bending strength of lumber.The most frequently determined strength parameter of materials is the modulus of elasticity in static bending. The parameter is a basis for the comparison of the technical value of timber: the higher the modulus, the better the technological quality of structural materials. As the structure of the wood is anisotropic, and to ensure some flaws can be masked, the value of the modulus of elasticity does not always translate directly into proportional bending strength. This problem makes it necessary to check properties, identified in non-destructive testing, with real strength. Since the evaluation of strength requires the destruction of the tested material, it is more advantageous to determine the relationship between the modulus and the strength of the laboratory test ,14,17.The numerous advantages of glued laminated timber enable its use in practically every type of building regardless of its intended application. This assumption is the basis for undertaking the quality testing of glued semi-products and components, taking into consideration their use for construction purposes.Assessing the impact of the quality of the various classes of timber originating from Polish forests to be used as sawn timber or glued components may provide valuable information to wood technology specialists in Poland, contributing to developments in the production of wood for construction applications in the form GLT (glued laminated timber).The aim of the study was to assess the quality of pine timber in a horizontal bending test. Pieces of timber intended for testing were obtained by sawing logs from model trees from a 125-year-old stand.The research material was pine wood with the following dimensions: 137 mm wide × 39.50 mm thick × 3485 mm long. The pine wood was obtained by sawing timber in the form of logs with round cross sections and originating from the Forest Division Olesno . The age of the tree stand was about 125 years, and the average tree height was 25 m. Butt-end long logs of about 14 m were obtained from every timber item. Each long log was sawn to provide four logs of about 3.5 m, which were marked as butt-end logs (O), middle logs (S)—2 items, and top logs (W). Each log was processed to obtain a flitch from which the main timber intended for manufacturing structural beams was obtained. Each timber item was measured to determine its linear dimensions, density, and modulus of elasticity (MOE). MOE was found by determining the deflection for a given load in accordance with the diagram shown in 4.The modulus of elasticity (MOE) of lumber is calculated from Equation (1):SYLVAC callipers with a measurement accuracy of 0.01 mm were used to determine the sawn timber section (thickness and width). To determine the length, a linear gauge with 1 mm graduation was used. Weight was evaluated using the Radwag tensometer scale. Moreover, the moisture content of each piece was determined using a Tanel HIT-1 hammer moisture meter.E12 is the modulus of elasticity of wood for a moisture content of 12%, N/mm2; MCE is the modulus of elasticity of wood for a moisture content of 4% < w < 20%; MCα is the coefficient of variation of the modulus of elasticity of wood after its moisture content changed by 1%, which is assumed to be 0.02; and MC is the absolute moisture content of wood, %.Since the moisture of the timber during the test differed considerably from 12% (between 10.2% and 13.5%), the outcomes were recalculated using Bauschinger’s Equation (2):The assessment covered 486 timber items (samples). Each piece was given an individual number so that it was easy to prepare the lumber sets for the production of beams.The results of the experimental measurements were analyzed using the STATISTICA 13.0 package . The obtained results were evaluated using ANOVA  variance analysis, whereas Tukey’s test was most frequently used to determine homogeneous groups.3 (average moisture 8.98%). The items obtained from the top and middle logs were characterized by similar densities. For those from the butt-end logs, the density was much higher (50 kg/m3)  .3. This was confirmed by previous observations and data concerning the number of items originating from the various locations along the tree length. It should be noted that the number of butt-end logs was half that of the middle logs.The tested timber did not follow a normal density distribution . Its den2 and in the second was 9.10 kN/mm2. The middle-section timber items were characterized by an average modulus of elasticity of 11.3 kN/mm2 (2 for a SD (standard deviation) = 2440 N/mm2, whereas in the test sample of timber, the average modulus was around 11,556 N/mm2 for a SD of 2554 N/mm2. This indicates that the adopted method of evaluation of the modulus of elasticity in this case provided convergent results for the modulus of elasticity.When analyzing density in accordance with EN 338 as an indicator of the strength class of coniferous timber, classes C24, C27, and C30 would comprise only one timber item each, C45 with nine items and C50 the remaining ones. This means that for this batch of timber, its strength is determined mainly by its modulus of elasticity. Statistically, significant differences between the moduli of elasticity were observed for timber items located in different sections along the tree length. The highest moduli were observed for the butt-end logs and the lowest or the top logs. In the first case, the mean value of the modulus of elasticity was 12.4 kN/mm3 kN/mm2 . Timber A more detailed analysis of the distribution of MOE values for the timber items of interest is illustrated in The broadest range was represented by the timber obtained by sawing the mid-section logs, which comprised both items classified as class C50 and classes below C14. The butt-end log timber, even though its modulus of elasticity was very high, comprised items of high average strength classes ranging from C14 to C50. The top log timber was represented both by unclassified items and those graded between C14 and C35.C24 is the timber class that is essentially used for roof truss systems and other load-bearing components. This class was represented by a rather low number of items, merely 5.7% of the analyzed timber items. On the other hand, there were only 48.6% of timber items below class C24. The region thus provides timber with exceptionally high mechanical strength, especially with regard to the parameter of interest, modulus of elasticity, which is loosely correlated with bending strength. Since the importance of the quality of timber, in this case, its modulus of elasticity, increases with a squared distance between the timber item’s axis and the beam’s neutral axis, then the higher the beam, the lower the grade of the timber that may be positioned nearer the neutral axis. This means that the higher the beam, the higher number of low grades of timber can be compensated with good grade timber positioned nearer the outer beams. Therefore, the authors chose to prepare such technical models of beams as could be obtained from the available timber.Pinus sylvestris L.) has a significant impact on the physical and mechanical properties of the wood from which they are made. Only butt-end logs (log type O) allows for the production of high-quality timber elements.The origin of the logs from the trunk , as found in the 4-point bending test to assess its modulus of elasticity.The pine timber from We used the horizontal model of evaluation of the modulus of elasticity of which the results, for the batch of interest, were similar to those obtained in an evaluation according to EN-408 ,28.


The Special Issue of the Manufacturing Engineering Society 2019 (SIMES-2019) has been launched as a joint issue of the journals “Materials” and “Applied Sciences”. The 29 contributions published in this Special Issue of Materials present cutting-edge advances in the field of manufacturing engineering focusing on additive manufacturing and 3D printing, advances and innovations in manufacturing processes, sustainable and green manufacturing, manufacturing of new materials, metrology and quality in manufacturing, industry 4.0, design, modeling, and simulation in manufacturing engineering and manufacturing engineering and society. Among them, these contributions highlight that the topic “additive manufacturing and 3D printing” has collected a large number of contributions in this journal because its huge potential has attracted the attention of numerous researchers over the last years. After the complete success of the first edition  with 48 Once again, this Special Issue was promoted by the Manufacturing Engineering Society (MES)  of SpainIn this Special Issue of the journal Materials, 29 contributions to cutting-edge advances in different fields of the manufacturing engineering have been collected. In particular, in additive manufacturing and 3D printing ,9,10,11;Among all of them, the topic additive manufacturing and 3D printing stands out for the number of contributions it has had in this Special Issue showing the interest that this topic arouses, currently, among researchers, the industry and the public in general. The works focus on the manufacturing processes ,5, the cFinally, it remains to highlight that in just four months since the publication of the first work , all the


Using PRI, a total of 928 patients could be provided/year compared with 500 patients if CMI are used. By using PRI, the cost/treatment was reduced by 46%. The cost of treatment dominated and the cost of time consumed by patients were also substantial. The societal cost of contributing to climate change was of low importance. By using PRI, the needs of 86% more patients could be met within the same budget. Using these methods, the contribution of healthcare systems to the 17 Sustainable Development Goals approved by the UN can be quantified.There is an increasing demand to quantify the footprints, ecological, economic and social, in terms of the effect of different interventions in healthcare. The aim of this study was to compare two systems providing patients with diabetes with insoles in terms of their ecological, economic and social footprints. Prefabricated insoles (PRI) were compared with custom-made insoles (CMI). Using a welfare-economic monetary approach, costs were estimated for (1) treatment, (2) travelling to and from the hospital in terms of both fuel and time consumed by the patients and (3) society through emissions contributing to climate change. The proportion of patients/year that could be supplied within the same budget, for each individual treatment, was calculated. The cost of the insoles was 825 SEK (PRI) and 1450 SEK (CMI), respectively. The cost, mean value/patient due to the consumption of patients’ time at the department, was 754 SEK (PRI) and 1508 SEK (CMI), respectively. Emissions, in terms of CO Insoles and appropriate footwear are frequently used to prevent pressure-induced diabetic foot ulcers (DFU) and footwear enables people to walk  are a group of diseases with a substantial impact on the health level of societies. These diseases are the cause of 41 million people deaths every year  in 2011. The number of patients in need of this specific healthcare once a year is approximately 10,000, while the number of persons receiving the treatment is estimated at 500. Real-world figures relating to the number of patients at risk are not registered. The estimate of 10,000 is related to the number of people with diabetes in Gothenburg, 20,000  according to Apelqvist et al.  and 71471It is assumed that an appropriate supply of insoles, as a part of an effective prevention strategy, will prevent the development of DFUs in 5% of the population studied  makes the assessments and measurements are taken. The custom-made insoles (CMI) are manufactured and fitted in an appropriate shoe on the second visit Figs. , 2 Hell.Fig. 1CuIn a new system, prefabricated insoles (PRI) are already delivered on the first visit, Fig. Table The price per pair of insoles is, for PRI, the price paid, while, for CMI, it is the cost of producing them, including labour.Labour is the time used when meeting the patients.By using PRI, the number of patients that are treated within the same budget increases by 86%. With the given budget restrictions, the percentage of patients in need of the treatment whose demands can be met increases from 5 to 9%. Table Table The societal cost of the emissions of climate change gases follows the route in previous studies , the cost to the patient of the time consumed is halved Table .Table with 500 patients treated with CMI, the healthcare system will save 2.8 million SEK in costs avoided due to 25 fewer cases of DFUwith 900 patients treated with PRI, the healthcare system will save 5.0 million SEK in costs avoided, due to 45 fewer cases of DFUwith 10,000 patients treated, the total need in the Gothenburg area, the healthcare system will save 55 million SEK in costs avoided, due to 500 fewer cases of DFUIn (1) and (2), the cost of delivering this treatment is 1.3 million SEK. The net savings in (1) are therefore 1.5 million SEK, while in (2) they are 3.7 million SEK. If PRI are used, the cost of meeting the needs of 10,000 people is 14.4 million SEK, making the net savings around 40 million SEK.In the method and study setting, it is assumed that 10,000 patients were at high risk in the Gothenburg area and 5% of these would develop DFUs, 500 per year. The future treatment cost saved for every DFU prevented is 110,000 SEK  and with the same budget, the need for insoles of approximately 900 patients annually in Gothenburg can be met, compared with 500 for CMI. The total number of patients in this area needing this treatment is 10,000.Assuming that 5% of the patients would otherwise have developed DFUs, the increase in the capacity to treat 400 patients reduces the number of DFUs by 20 a year  a secure supply of insoles and shoes and (2) the need to minimise travelling and social interaction  alternatively 40 million SEK (the PRI system) in a region with a population of 500,000 people. The cost of this would be around 25 million SEK in the CMI system and 15 million SEK in the PRI system.The results show the importance of the way the work is organised at low system level in the healthcare sector where one system (PRI) per treatment can reduce the ecological, economic and social footprint by 50%, 46% and 46%, respectively. Efficiency in healthcare, in traditional terms, contributes to efficiency in a broader sustainability contextThere is substantial potential for improvements at low system levels that make a difference to sustainable development at high system levelsIn the case studied, the efficiency was almost doubled by reducing patient visits by 50%, while the treatment effects were similarMeasures substantially improving efficiency at low system levels significantly increase the number of treatments delivered within the given budget restrictionsWith regard to needs, the current supply of insoles to patients with diabetes is far too low, producing costs to patients and to society through an increased level of DFUsWhen designing efficient healthcare systems, the cost of the consumption of patients’ time should be consideredThe environmental impact is of minor importanceWhen measuring the environmental impact, both direct and indirect support from nature, from ecosystems, should be consideredIn the case of the delivery of insoles to patients with diabetes, the results obtained indicate thatWith a global economy trespassing on ecological sustainability limits and the substantial health costs due to a degraded environment, the demand for methods evaluating links between ecological, economic and social systems is important and it is increasing. The capacity to handle interrelations with human health and healthcare systems is critical.Our major findings are:By using PRI, compared to CMI, one visit to the healthcare supplier was needed instead of two. The cost/treatment for the healthcare supplier was reduced by 46%, allowing the treatment of 86% more patients within the same budget.In our example, the costs for the healthcare supplier in the PRI-case was 63% of the total costs, the costs of the consumption of the time of the patients was 33%. The result stresses the importance of considering the costs associated with the time consumed by the patient when optimising healthcare systems.The paper demonstrates a method with the capacity to quantify impacts on the 17 SDG constituting the 2030 Agenda for Sustainable Development.


We first calculate the heat capacities of the nonlinear electrodynamics (NED) black hole for fixed mass and electric charge, and the electric capacitances for fixed mass and entropy. Then, we study the properties of the Ruppeiner thermodynamic geometry of the NED black hole. Lastly, some discussions on the thermal stability of the NED black hole and the implication to the flatness of its Ruppeiner thermodynamic geometry are given. The thermodynamics of black holes are established on the basis of the definitions of the entropy and temperature of black hole ,2,3,4. TN thermodynamic variables including the entropy, the internal energy, and so on, one can construct the corresponding thermodynamic geometry associated with the entropy, the internal energy and other thermodynamic variable [For the thermodynamic system described by the variable ,7,8,9. Tvariable ,36,37,38variable ,40,41,42variable ,46,47,48variable . So, it In this paper, we study the thermodynamic properties and the properties of thermodynamic geometry of the regular NED black hole. In g and R are the metric determinant and Ricci curvature scalar associated with metric P, The action of Einstein gravity coupling to the nonlinear electrodynamics is (1)S=116Recently, some regular solutions in Einstein gravity coupling to the nonlinear electrodynamics have been obtained ,52. For n yields (5)m(r)=M and q are the mass and electric charge of the NED spacetime. The NED black hole possesses the two horizons with the outer (inner) horizon radius ForIn the following, we will discuss the thermal and electric properties of the NED black hole. Fromr in the spherically symmetric spacetime takes [From me takes (11)ENEDPutting Equation  givesy+=ln[12xM fixed. At Clearly, From the formula for the electrostatic field 1r2dσdr) , the eleE gives the electric potential of the NED black hole as [Integrating the electric field  hole as (20)Φ(r)For the extremal black hole, the electric potential on the horizon of the NED black hole reduces to The electric capacitance of the NED black hole is defined asM, the electric capacitance of the NED black hole is obtained asFor a fixed As M fixed and the one with As quations  and 27)y+→−1, K+The NED black hole possesses the two horizons for The entropy and temperature of the inner horizon of the NED black hole are ack hole .In terms of Clearly, both Putting Equation  with C˜=The two electric capacities of the NED black hole associated with the inner horizon areAt S is the entropy of the thermodynamic system, and Some thermodynamic properties of the thermodynamic system may be studied by the thermodynamic geometry method ,7,8. TheFor the black hole with two horizons described by the two thermodynamic quantities, the Ruppeiner metric associated with the entropy of the outer horizon takes the formg+R=For the Ruppeiner metric , all theSimilarly, one can construct the Ruppeiner thermodynamic geometry metric associated with the inner horizon of the NED black hole as quations –45) und undg−ijRM and q. The other associated with inner horizon may be described by M and q. Both of the Ruppeiner thermodynamic geometries associated with the outer and inner horizons of the NED black hole are flat. This reflects that there is no interaction between the particles in the two thermodynamic systems [The thermodynamic properties and the Ruppeiner thermodynamic geometry of the NED black hole have been studied. The thermodynamic systems related to the outer horizon and the inner horizon of the NED black hole satisfy the first law of thermodynamics with the internal energy quations  and 18)ENED±=12rquations  and 31)ENED±=12r systems . As a re


In many previous studies, the preventive effects of peanut against aging and cognitive impairment have often been unclear, so to clarify the effects we first investigated effective markers for evaluating its effects in the hippocampus of senescence-accelerated mouse prone/8 (SAMP8) mice, mainly using proteomics. The effects of dietary high-oleic peanuts on the hair appearance of SAMP8, the expression of effective markers in the hippocampus, and the TBARS and amino acid contents of the hippocampus were examined. Hippocampus solute carrier family 1 , calcium/calmodulin-dependent protein kinase type II, and sodium- and chloride-dependent GABA transporter, which all are considered to be closely related to glutamic acid concentration were decreased by feeding of the samples, and the GABA/glutamic acid ratio in the hippocampus was increased by feeding with the samples. The formation of glial fibrillary acidic protein and synapsin-2, which showed higher levels in the SAMP8 than in SAMR1, and the protein expression of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein and dihydropteridine reductase, which are considered to be related to the formation of adrenergic neuron transmitters, were reduced by the feeding of peanuts and their germ-rich fraction. Ferulic acid, as an ester and minor component in peanuts, could be partly connected to the effect of peanuts. These results indicate that high-oleic peanuts and their germ-rich fraction can protect against aging and cognitive impairment by regulating protein expression, which could be measured by the proteomics of the above hippocampus proteins of SAMP8 and the hippocampal GABA/glutamic acid ratio. Roasted peanuts, which are widely consumed as cakes containing sugars and/or other food additives, are favored by many people in Japan because of their characteristic taste and flavor, and the number of products made with them is increasing. However, since most of the germ is detached from wholegrains in the process of dehulling the astringent inner skin of the roasted peanuts by grinding, only parts of cotyledon and the other parts without germ are used for cake making. The development of methods for the utilization of the germ as a food material for other food production, as well as in functional foods, is being investigated in the food industry.It has been pointed out that intake of peanuts with high-oleic acid may improve cerebrovascular and cognitive function , and it For the first step in this study, markers which are able to evaluate the effect of samples on reducing aging and cognitive impairment were selected by an analysis of amino acids and a proteome analysis of the hippocampus of SAMP8 and senescence-accelerated resistant mice (SAM-R1). Then, the effects of the samples on the markers were evaluated and compared among the samples. There have been some reports that clearly showed the relation between glutamic acid and other amino acid contents in the hippocampus and cognitive disease or aging ,7. We thPeanuts (Runner species) with a high-oleic acid content (oleic acid content of over 70%) were obtained from Texas, America, and roasted for several minutes. The part detached from the whole part of peanuts during the dehulling of the astringent inner skin of the roasted peanuts by grinding was used as the germ-rich fraction in this experiment. The lipid contents of the whole peanuts and the germ parts were 50.2% and 44.0%, respectively. The carbohydrate, protein, lipid, ash, and moisture percentages of the roasted whole peanuts were 19.6%, 25.5%, 50.2%, 2.3%, and 2.2%, respectively, and those of the germ parts were 26.0%, 23.6%, 44.0%, 2.8%, and 3.2%, respectively. Ferulic acid detected as a minor component of peanuts after its alkaline hydrolysis with 2N-NaOH at 30 °C for 30 min was also used in this experiment. It was purchased from Sigma-Aldrich Japan  and used for the animal experiment.n = 6), basal diet with peanuts (wholegrain) , basal diet with germ from peanuts , or basal diet with ferulic acid . The composition of each experimental diet is shown in Six-month-old senescence-accelerated mice (SAMP8) and senescence-accelerated resistance mice (SAMR1) as a control were purchased from the Shizuoka Laboratory Animal Center  and cared for according to the institutional guidelines of Yamagata University. The approval no. of the Institutional Animal Care and Use Committee of Yamagata University was 2905 (IACUC number: 2905). Mice were housed individually under a 12:12 h light–dark cycle at 22 ± 2 °C and 40–60 humidity. After acclimating for 3 days, the mice were randomly divided into six groups of five or six mice and fed either a basal diet  by grinding with a plastic pestle, then ultra-sonicated for 15 min in an ice bath, followed by centrifugation at 1.1000 rpm for 15 min to obtain a protein pellet and supernatant , in whicg for 20 min at 5 °C. The obtained supernatant was freeze-dried and re-dissolved with a small amount of H2O, followed by centrifugation at 10,000 × g for 20 min at 5 °C. Finally, it was analyzed by a UPLC ESI-Q-TOF MS/MS system .The protein pellet for proteomics was suspended using the RapiGest SF  solution, followed by the reduction and alkylation of the cysteine residue in protein   and then2O (solvent A) and 0.1% HCOOH in acetonitrile (solvent B). A linear gradient of B in solvent A (100% of B at 45 min) was used. The spectra were acquired in positive ion mode in micro Q-TOF with a mass range of 50–2000. The source temperature was set as 120 °C. Protein identification was carried out using ProteinLynx , and a database of the mice (taxonomy ID: 10088) was provided by NCBI . The carbamidomethylation of cysteine and oxidation of methionine were considered to be variable modifications of tryptic peptides in MS/MS analysis. Differential protein analyses were performed after data normalization using the ProteinLynxTM Gloval Server (version 2.3) .The separation of peptides in the supernatant by the UPLC  was performed on a BEH C-18 column  using a solvent system composed of 0.1% HCOOH in Ht-test. All comparisons were considered statistically significant at p < 0.05.Each value is given as a mean ± SEM for six animals, except in the case of the SAMP8 + F group in which five animals were used. The homogeneity of variance between treatments was verified by Bartlett’s test. Data were statistically analyzed using a one-way analysis of variance. A post-hoc analysis of significance was performed by Tukey’s multiple range test. A comparison between two groups was carried out using the Student’s Although the food intake of each group was not different statistically, the body weight of the R1 + H group showed a tendency to be higher than the other group from the middle to the latter half of the period .It is reported that some of the food and its components could reduce brain amyloid beta accumulation, and cognitive deficits and promote the antioxidative defense system in SAMP8 . HoweverAlthough glutamic acid is thought to play an important role in the functions of learning and memory, its abundant accumulation in the brain is believed to be involved in the pathogenesis of a variety of neurodegenerative disorders in which cognition is impaired . This inAn increase in the hippocampus GABA content in the P8 + H, P8 + G, and P8 + F groups in the comparison with the P8 group see , though p values, which are higher and lower than 0.95 and 0.05, respectively, show that the protein amounts determined by proteomics are significantly higher and lower in the sample-added group compared to the control, or in the P8 group compared to the R1 group.The number of proteins and/or peptides with an accession number, which were identified in differential expression analyses and registered on the NCBI database, was 1400–1600. As there were many proteins identified based on the NCBI database, only proteins that showed significant changes by the differential expression analysis of the protein and/or peptides, which are reported to be influenced in the hippocampus of aged mice and rats, and those of SAMP8 as a model of cognitive impairment ,23,24,25Glial fibrillary acidic protein, which is reported to be increased in the brain of mice with accumulated beta amyloid and/or aged SAMP8 ,26, was As an increase in TBARS in the hippocampus of SAMP8 in comparison with SAMR1 was suppressed by the feeding of peanut wholegrain and its germ-rich fraction, we examined by proteomics what kind of antioxidative enzymes concerned with the scavenging of active oxygen species are regulated by feeding with samples in SAMP8. As it is known that the Mn-SOD level in the brain cortex is higher in SAMP8 mice that are 15 weeks old than in SAMR1 mice that are 8 weeks old , the effThe tendency of the suppression of the protein expression of glutathione S-transferase (GST) in the P8+ H and P8 + G groups, compared to the P8 group , and a decreasing tendency in the fold change of the protein expression in the calcium/calmodulin-dependent protein kinase type II , are both compared to those of the P8 group by feeding peanut and germ-rich fraction, which may indicate that the amount of glutamic acid in the synapse was decreased by feeding peanuts and the germ-rich fraction, resulting in decreases in the amount of glutamic acid which could be transported and in the down-regulation of glial high-affinity glutamate transporter in the glial cell. No change in the fold change of the glutamic synthase by feeding samples is considered to be reflected by the lower glutamic acid concentration in the hippocampus. These results may also indicate that the degree of fold changes in the expression of these enzymes could become a marker for the determination of aging and cognitive impairment.Calcium/calmodulin-dependent protein kinase type II (CaM kinase II) is known as one of the most prominent protein kinases and is most concentrated in the brain. Neuronal CaM kinase II is widely distributed in the brain and regulates neuronal functions, including the synthesis of neurotransmitters such as glutamic acid, neurotransmitter release, the modulation of ion channel activity, cellular transport, cell morphology, neurite extension, synaptic plasticity, and learning and memory , suggestThe amounts of sodium- and chloride-dependent GABA transporter, which showed a tendency to be decreased in the P8 group in the comparison with R1 group , suggesting that peanuts and their germ-rich fraction could inhibit increase in the synapsin-2 level, which might be involved with aging. This result also suggests that the hippocampus synapsin-2 level could also become a marker for the evaluation of aging and cognitive impairment and for the development of food available to protect against aging and cognitive impairment, as suggested by Asamoto et al.As it is reported that synapsin-2 is concerned with the formation and maintenance of synapses in the culture of hippocampus  and withp: 0), 0.97 (p: 0.04) value), may indicate that the feeding of peanut and its germ-rich fraction may not able to improve the plasticity of the brain.Hippocampus tublin-alpha is considered to be important for the preservation of plasticity of the brain, and it is reported that its levels in the hippocampus are lower in old rats than younger rats . A valueAs it is known that the protein expression of hemoglobin subunit alpha and beta are lower in the hippocampus of old rats than young ones when measured by proteomics , the dieAlthough, to date, a few reports have dealt with the possibility that peanuts may improve cognitive disorders in middle-aged and elderly subjects , there aAs SAMR1 and SAMP8 fed with high-oleic peanuts showed lower hippocampus TBARS levels, a delay in oxidation in vivo and/or in the hippocampus in mice fed with high-oleic peanuts may be related to the effect of peanuts. A low content of fatty acid, which is prone to oxidation, and the presence of anti-oxidative polyphenols such as p-coumaloyl tartrate and feruloyl tartrate in high-oleic peanuts are also considered to have contributed to the suppression of oxidation. However, more experiments may be necessary to clarify the action mechanism of high-oleic peanuts, including the mechanism of its effect on the protein expression of markers.As summarized in


The calculations have shown that Si atoms in silicon carbide at the interface, which are the most distant from the Si atoms of the substrate and do not form a chemical bond with them (there are only 12% of them), provide a sharp peak in the density of electronic states near the Fermi energy. As a result, the interface acquires semimetal properties that fully correspond to the ellipsometry data.Thin films of single-crystal silicon carbide of cubic polytype with a thickness of 40–100 nm, which were grown from the silicon substrate material by the method of coordinated substitution of atoms by a chemical reaction of silicon with carbon monoxide CO gas, have been studied by spectral ellipsometry in the photon energy range of 0.5–9.3 eV. It has been found that a thin intermediate layer with the dielectric constant corresponding to a semimetal is formed at the 3C-SiC(111)/Si(111) interface. The properties of this interface corresponding to the minimum energy have been calculated using quantum chemistry methods. It has turned out that silicon atoms from the substrate are attracted to the interface located on the side of the silicon carbide (SiC) film. The symmetry group of the entire system corresponds to  Silicon carbide (SiC) is currently one of the highly demanded wide-bandgap semiconductors . Its mec4 is also a supplement to obtain a uniform Numerous studies have shown that the growth of SiC from the material of the Si substrate proceeds in parallel in two ways. The first way is the coordinated substitution of atoms that leads to an epitaxial 3C-SiC film with a thickness of about 100 nm on the sample surface ,3,4. Theand pits . The secand pits . As a reA number of studies have shown that the ellipsometric spectra of the 3C-SiC(111)/Si(111) samples cannot be described by classical ellipsometric models, in contrast to other similar cases. The reason is that the classical theory uses the Effective Media Approximation (EMA) at the interface between two known materials . In partpsometry . AccordiIn this work, it has been revealed for the first time that at the interface between 3C-SiC(111) and Si(111) a thin layer is formed with semimetal properties that cardinally differ from the properties of both SiC and Si and cannot be obtained within the EMA framework. This is caused by the absence of misfit dislocations and by the complex nature of the interaction of two surfaces when the SiC layer attracts individual Si atoms from the substrate. As a result, an interface structure is formed in such a way that 88% of Si atoms at the interface form chemical bonds with the substrate atoms, and 12% of Si atoms at the SiC(111) interface do not form bonds, since they are too far from the Si atoms of the substrate. Such a structure has been described in detail by the methods of quantum chemistry within the framework of the density functional theory. It has been shown that p-electrons of 12% of Si atoms at the SiC(111) interface with dangling bonds provide a sharp peak in the density of electronic states exactly in the Fermi energy region. The conduction band in this case either touches or even goes deep into the valence band by an amount of the order of several hundredths of an eV, which nearly corresponds to the calculation error or is less than it. It has been shown that this theoretical representation is in complete agreement with the experimental results of ellipsometry, according to which the optical properties of the layer at the 3C-SiC(111)/Si(111) interface correspond to the Tauc-Lorentz (TL) parameterization  with a b4 (5%) was added to the CO gas. The technological details of the process of epitaxy by the method of substitution of atoms are given in the review [2 is not formed. Analysis of the pressure–flow rate phase diagram for this system showed [2 can be formed at elevated CO pressures due to the reaction 2 starts to form is The growth of SiC films was carried out from Si(111) and Si(100) substrates by processing them in a vacuum oven at a temperature of 1280 °C with carbon monoxide gas according to reaction (1). The CO gas pressure and flow rate were 70–350 Pa and 10–20 mL/min, correspondingly. The growth time was in the range of 10–40 min. To obtain uniform SiC layers without pits and cavities, a small amount of silane SiHCO = 150 Pa, the silane volume fraction of 5%, and the growth time of 20 min. The same figure shows the theoretical ellipsometric spectrum obtained in the framework of the simplest model consisting of only one layer of the film. That is, the lowest layer is the Si substrate containing, within the Bruggeman EMA approximation [Ellipsometric analysis of the obtained samples allows them to conditionally divide them into two types . The firximation , pores aximation . This feximation . The poiximation . Furtherximation . For thiximation . Since tximation . We nameximation . In partIt is important to emphasize that almost all SiC samples grown on Si by the CVD  method, regardless of the substrate orientation, belong to the first type of samples, i.e., samples that are described with high accuracy by the simplest ellipsometric model. For example, CO = 100 Pa (the proportion of silane in CO was 5%). Different thicknesses of SiC films grown under the same conditions, but on Si substrates of different orientations (in this case (111) and (100)) are explained by the different hydraulic diameters of channels in the SiC crystal along which CO and SiO gases move towards each other [2 in the samples of either the first type or the second type.We refer to the second type of SiC/Si samples as those that cannot be described by any obvious ellipsometric model in principle. Almost all samples grown on Si(111) by the method of coordinated substitution of atoms belong to this type. For example, ch other , which sIn this work, we are of the opinion that the method of coordinated substitution of atoms forms an interfacial 3C-SiC(111)/Si(111) layer with completely new optical and electrical properties. The growth of SiC on Si(111) by the CVD method does not form such a layer at the interface . It has been found by electron microscopy that lattice misfit dislocations at the 3C-SiC(111)/Si(111) interface are absent, and instead of them, so-called partial dislocations are formed, leading to the formation of stacking faults with interlayers of close-packed hexagonal phases (4H-SiC and 6H-SiC) within the main phase of cubic silicon carbide . Neverth3m1P symmetry. If we consider the interface between Si(111) and the C surface of SiC(111), then SiC will attract not 1 but as many as 3 Si atoms out of 16 (in full accordance with the requirement of 3m1P symmetry). Consequently, the deformation energy of the interface will be somewhat higher, but not much. Thus, it follows from the quantum-chemical calculations that the surface of a 3C-SiC(111) film growing on Si(111) by the method of coordinated substitution of atoms should be of the C-type since the Si-type surface is oriented toward silicon. A comparison of the total energy of the entire system for these two cases is beyond the scope of this work since here it is necessary to take into account the real reconstruction of the SiC surface [To describe the 3C-SiC(111)/Si(111) interface and calculate its properties, we use the methods of quantum chemistry in this work. More specifically, the energy of the 3C-SiC(111)/Si(111) system has been calculated within the framework of the density functional theory and the optimal configuration of atoms corresponding to the minimum energy has been found. For this purpose, the MedeA-VASP (MedeA Vienna Ab Initio Simulation Package) package  was util surface .An interesting feature of the found interface is that its bandgap decreases to almost 0. Calculation of the band structure of this system shown in Ellipsometric analysis of the 3C-SiC(111)/Si(111) samples has shown that, at the interface between the SiC and Si semiconductors, a layer appears with unusual optical properties, which cannot be described in the framework of EMA in principle . To descThe Si substrate is represented by a mixture with voids and 3C-SiC taken in equal volume fractions. The dielectric constant of the mixture is calculated within the framework of the classical EMA Bruggeman model (2). Equal fractions of silicon carbide and voids arise from the fact that the volume of the initial Si cell is 2 times greater than the volume of the 3C-SiC cell resulted from reaction (1). The first layer on the substrate is a semimetal layer with unknown optical properties, so they are described by the model of one TL oscillator.E is the photon energy, ε2 is the imaginary part of the dielectric constant  is simplified, and the number of the minimization parameters of the model is reduced to 3. We emphasize that the thickness of the first layer  h1 , A, E0,etal) h1  stronglyh2  (at gE = 0) makes it possible for the first time to adequately describe the experimental ellipsometric data . That is, in the frequency range of an electric field of 700 THz and over, the interface layer conducts current like a bad metal. However, in the region of low frequencies, its conductivity deteriorates significantly and becomes similar to the conductivity of a semiconductor with a zero bandgap [The second layer is 3C-SiC with a thickness h2 , containh2  surface are fundamentally different from the ellipsometric spectra of similar layers grown either by another method or on a Si surface with a different orientation. The reason was found to be that at the interface of 3C-SiC(111)/Si(111) there is an intermediate layer whose dielectric constant cannot be described within any EMA model. By its appearance, the dielectric constant is mostly similar to that of a semimetal and is well described by the Tauc-Lorentz model with zero or very small (< 0.5 eV) bandgap. The root-mean-square error in the description of ellipsometric spectra decreases by about 3 times by using the TL model as compared to the EMA.A quantum-chemical model of the 3C-SiC(111)/Si(111) interface has been constructed, which explains the reasons for the appearance of the layer with the properties of a semimetal. It has been shown that, for dislocation-free matching of SiC and Si lattices differing by 20%, the SiC film oriented with its Si surface toward the substrate attracts one of 16 Si atoms in the nearest double atomic layer of the substrate. At that, 22 out of 25 Si atoms form chemical bonds with the Si atoms of the substrate, and 3 out of 25 atoms  do not form bonds, since they are too far from the substrate atoms (over 3 Å). The p-electrons of namely these Si atoms in SiC make the main contribution to a narrow and sharp peak of the density of electronic states of 3C-SiC (111)/Si(111), located in the vicinity of the Fermi energy. In other words, the 3C-SiC(111)/Si(111) interface must have unusual electrophysical properties, in particular, it must conduct electric current well. The measured ellipsometric spectra show that the conductivity of the interface is only 2 times worse than that of a metal like lead at electric field frequencies over 700 THz. The conductivity deteriorates at lower frequencies.