This paper presents a pan-tilt-zoom (PTZ) camera-based displacement measurement system, specially based on the perspective distortion correction technique for the early detection of building destruction. The proposed PTZ-based vision system rotates the camera to monitor the specific targets from various distances and controls the zoom level of the lens for a constant field of view (FOV). The proposed approach adopts perspective distortion correction to expand the measurable range in monitoring the displacement of the target structure. The implemented system successfully obtains the displacement information in structures, which is not easily accessible on the remote site. We manually measured the displacement acquired from markers which is attached on a sample of structures covering a wide geographic region. Our approach using a PTZ-based camera reduces the perspective distortion, so that the improved system could overcome limitations of previous works related to displacement measurement. Evaluation results show that a PTZ-based displacement sensor system with the proposed distortion correction unit is possibly a cost effective and easy-to-install solution for commercialization. Displacement measurement is an important technique required in diverse industries, such as construction, machinery, and robotics. In particular, displacement measurement of critical structural positions in large structures is a vital component of structural health monitoring (SHM). Extensive research has been conducted in the field of displacement measurement, including how well structures are designed to effectively respond to external disturbances such as earthquakes and heavy winds, as well as the level of structural risk that could lead to a building collapsing .Existing contact-type sensors designed to measure displacement have limitations. For example, displacement measurement of large structures, such as a bridge, is difficult to measure due to installation challenges at critical structural positions , limitatEmerging research is focused on displacement measurement technologies that rely on cameras instead of contact-type displacement sensors to measure structural displacement. This is accomplished by using vision-based measurement technologies that recognize and measure the displacement of markers attached at critical structural positions.An effective SHM system includes displacement measurements at both low and high frequencies. At extremely low frequencies, displacement measurement focuses on the excess lag and the load of a structure over time, while at high frequencies, displacement measurement is focused on structural stress caused by external, environmental disturbances, such as earthquakes or heavy winds. While SHM is concerned with displacement at either frequency, monitoring at low frequencies should take priority, as the critical points of a structure can move slowly over time and monitoring at an extremely low frequency can provide early warning symptoms of building collapse, hence preventing such a collapse from occurring. In this respect, a previous approach measuring displacement at an extremely low frequency through a vision-based displacement measurement system was introduced, so that the risk of a bridge collapsing could be detected in advance .The accuracy of vision-based displacement measurement technology is the most critical aspect for commercialization, which is at the core of recent displacement measurement research  by statiMoreover, Fukuda developed a stand-alone vision-based displacement measurement system, based on a connected laptop and camcorder, which allowed displacement measurement to be achieved through a wireless Internet connection and further reinforced the cost and installation advantages of vision-based displacement measurement systems .Outside of these studies, Park  and Lee The latest advances of vision-based sensors and their applications are introduced. A cost effective vision-based structural health monitoring approach has been presented , in whicDespite these advantages, conventional studies on vision-based displacement systems have relied on images generated from a fixed viewing angle camera, which necessitated a trade-off between the field of view (FOV) and spatial resolution. In other words, any effort to increase the FOV by raising the number of markers resulted in a decrease in spatial resolution. Similarly, any effort to increase the measurement accuracy by increasing the spatial resolution resulted in a lower number of markers and decreased FOV. Hence, conventional studies on displacement measurement relied on 1–2 markers per camera to measure displacement in large structures or focused on smaller structures for experiments.The existing methods have limitations in terms of measurable range because they are based on the fixed camera with the narrow and constant FOV. This paper proposes a vision-based displacement measurement system based on a pan-tilt-zoom (PTZ) camera, which can extend the measurable range on monitoring displacement.To perform an early estimation of collapse risk for a building structure, we assume that displacement happens at very low frequency and the positioned markers slightly move along the plane on which markers are attached. Markers’ displacement will be monitored sequentially using visual information described on markers.The algorithm underlying the PTZ displacement measurement system can be explained as follows. First, template matching is applied to find the region of interest (ROI) of the marker.Although we adopt the RANSAC ellipse fitting-based model with coordinates of marker contours in the ROI, the center point of the marker is detected in sub-pixel accuracy. As it relates to the accuracy of displacement measurement, the center point is mapped to the perspective distortion correction plane which we call the standard plane.This paper is organized as follows: As shown, each marker consists of five red circles based on information acquired from the camera related to the attached marker plane. As represented in This paper proposes an algorithm for a PTZ system that can largely be divided into two key processes. The first process involves constructing preset data based on diverse information collected in advance on marker images and PTZ marker coordinates needed to measure displacement. The second process then utilizes the preset data to film the markers and measure the displacement. Constructing preset data is achieved through the following steps. First, the measurable plane for a marker is located by manually using the pan-tilt-zoom functions of the PTZ camera, with the relevant PTZ coordinates then entered into the preset data. Second, a specific minimum bounding rectangle (MBR) based on the marker, has to be manually registered by the administrator monitoring the target building. Third, feature points are extracted from the template image with the central point of the four most outer points, which are used to eliminate perspective distortion. Finally, from this, a homography is calculated, for which the details are explained in i-th marker. i-th marker with The result of applying the process shown in i-th marker from relevant marker images. This is achieved by manually controlling the PTZ camera to locate a measurable marker plane, and then entering the PTZ coordinates of the location in the preset data as The first step in constructing the preset data is entering the PTZ coordinates of the i-th marker ..cx,cy) aquations  represenWe first construct an ellipse model by using all extracted contour points, and determine the optimal coefficients through the RANSAC Ellipse Fitting algorithm. By applying the RANSAC method, outliers become contour coordinates of the other four circles, therefore we could construct an ellipse model for a specific circle in the target marker. These procedures are iteratively applied for five circles to construct the ellipse models. Finally, we use the center points, which are extracted from these five elliptic models, as feature points.y, smallest x, largest y, largest x, and the last remaining point as 1st, 2nd, 3rd, 4th, and the 5th featured point, respectively. The 1st~4th points are used as a reference to calculate homography, and the 5th point is mapped into the standard plane to perform displacement measurement.The five extracted feature points need to be labeled to determine which points correspond with the expected references for homography calculation and displacement measurement later. We labeled four points with smallest The circles on the target wall are projected as ellipse on the camera-captured plane. This is why we extract the feature point by modeling the circle of the marker as ellipse. This approach results in a more reliable characterization of the tilt relationship between the marker plane and the projected plane. In addition, this approach effectively selects data by eliminating the outlier, therefore the center position can be reliably determined under the situation in which the edge is unclear or partially covered by other obstacles. We could measure the center position at sub-pixel resolution by using only the inlier in this paper.The target plane, on which the marker is attached, is not parallel with that on the camera sensor. That is why the perspective distortion in the captured image is inevitable. The displacement of the marker on the target plane has to be measured after the perspective distortion effect is compensated by considering the locational relationship between two planes.X point on the x-y plane into a newly-projected point In this paper, for accurate measurement of the marker displacement, we adopted homography to eliminate the perspective distortion. As shown in x–y plane, and these correspond to the points R  distance away from origin R from these four points is the same, and they intersect at 90The points H is a H can be calculated through the direct linear transformation (DLT) algorithm [Homography is a linear transformation which can be expressed through the following equation:lgorithm .R in In this paper, a minimum of four points is needed for the calculation of the homography matrix to map the marker plane to the standard plane by applying the direct linear transformation (DLT) algorithm . R in Fix–y coordinates of the pre-converted image and H is entered into the preset data as The homography is determined through a mapping process using the DLT algorithm, based on N displacement. This process is depicted in This paper proposes that displacement can be measured by applying an algorithm to PTZ camera images—a six-step sequential process to measure i-th marker from relevant marker images. In As explained earlier in Based on the marker images, the ROIs are found by template matching with a template image, which is stored in preset data MTi . The temT is the template image in which the position See the x–y plane is represented as the ellipse center point The displacement of the marker on the target wall must be calculated by projecting the marker plane into the perspective distortion-corrected plane as a standard plane. The first step in calculating the displacement involves finding the center point H-matrix as a statically determined constant table, which is calculated in the previously captured stage. Starting from the center point x, y coordinates to the x, y coordinates of the marker. The magnitude of the determined displacement (x-direction and (y-direction can be represented by the following two equations:The displacement measurement in the current level is based on the MD) can be represented by the following equation:K means the number of rounds in capturing the image; The magnitude of the total displacement (H matrix that we used for the first marker (marker 1).In addition, the following equation is an example of the We register the extracted ROI image as a template image i-th marker and the displacement algorithm process finishes.The homograph matrix, which is used to transform the target plane of a marker into the standard plane, has to be recalculated. The recalculated homography The feature point extraction based on the Otsu threshold method is less sensitive according to consistent illumination fluctuation over all the circles of the marker surface. Local variation of light level on markers affects the threshold level change on a specific segmented region. Perspective distortion of the marker always results in an ellipse circle regardless of the direction from which the camera captures image, thus this assumption helps efficient feature extraction from the distortion information.The purpose of this paper was to verify the performance effectiveness of a displacement measurement system based on images generated by a PTZ camera. We evaluate the proposed system on markers moving at a low frequency to observe the accuracy of displacement measurements. Markers used in the tests are shown in The test environment setup is described in The camera can acquire an image at 30 frames per second for each marker, but in this experiment, the camera captures 10 images and transfers them to the host computer in one second by considering the bandwidth of wireless communication. This means that the allowed time to perform the analysis for one image is 100 ms. Our implemented system could perform the entire algorithm for displacement measurement at 73 ms processing time. We performed the analysis for 10 captured images for each marker per second, and the rotation of the camera angle takes one second, therefore the processing time for each marker is 2 s. The sequential analysis for the other markers is iteratively performed by rotating the camera. Therefore, one round of analysis for all nine markers, which is described in The tests were conducted on nine markers with distances from the camera between 5 m and 72 m, by capturing the image using H.264 codec at 1920 × 1080 resolution, as shown in y-direction is more severe than that in the x-direction. The marker image, which is installed on the target wall, is projected into the another plane of the camera. This causes spatial distortion in terms of the position of the projected circles because the image sensor in the camera spatially captures the circle image at the different resolution relatively. In this case, in terms of the distorted angle, the error of displacement, which is measured in the y-direction, is slightly larger than a result in the x-direction.As shown in The evaluation results are summarized as follows:A Though the distance between the camera and target marker increases, spatial resolution variation, as a result of displacement measurement, is relatively smallThe existing vision-based displacement measurement approaches using a lens with fixed magnification result in large degradation of spatial resolution according to the increase of distance between the camera and marker. Consequentially, they require more accurate lens specification to cover maximum distance, or to extend the measurable range. Because our approach could utilize a specific zoom level and lens angle based on the PTZ camera considering the marker location for multiple markers, our implemented system results in stable spatial resolution although the distance is largely increased, as shown in RMS with the following equation:The measured displacement, which is multiple captured, is statically represented in terms of GT) means the actual displacement value that we manually moved as a reference, for which 5 cm, 10 cm, 15 cm, 20 cm, and 25 cm are used for our experiment in GT is 100.B Extend the measurable range by monitoring the target at a slightly slower sample rateAs explained, we adopted a PTZ-camera-based vision sensing approach to monitor markers, which are installed in various locations. Our approach enables to extend the measurable range of monitoring the target structure, compared to the existing methods. The following The existing approaches monitor the displacement for the static target on the static spatial plane, but our approach introduces a case study for the multiple markers on the structures, which are distributed at various distance of 5~72 m. The individual planes on multiple markers are sequentially projected to the standard plane of the PTZ-based vision system based on the proposed distortion cancellation technique. Our approach considers monitoring all markers with one PTZ camera, so that the total sample rate in monitoring the target will be decreased, but this drawback can be ignored due to extremely slow movement of the building structure as an assumption.There are also various factors causing additional errors in the measurement result compared to the actual displacement, which is manually controlled by the test environment and measured by the conventional distance-measuring instrument. Considering application-specific requirements, we assume that the proposed system recognizes the centimeter-order movement on the target wall. Our experimental environment could measure displacement at the millimeter scale. The camera calibration, which reduces the errors caused by the lens distortion, has to be performed for more accurate measurement at specific zoom levels, distances, and angles for the multiple targets. The experiment is done for multiple targets at various distance and with a wide range of angles. The current status of this approach is still lacking with regards to providing a statistical analysis and calibration by the camera lens distortion. This paper focuses on introducing the feasibility of displacement measurement using a PTZ-based vision system. More analysis of the quantitative relationship causing the measurement errors is needed to improve the total accuracy and resolution in future work.In this paper, we propose a PTZ camera-based displacement measurement system for the early detection of building destruction. Our study focuses on extending the measurable range and measuring displacement accurately. In this system, markers, which are attached on the main parts of the building, are used to represent the low frequency movement of the building. By using the PTZ camera, we can automatically acquire the marker images sequentially in predetermined order in the preset data and extend the measurable range. The acquired image is transmitted to the host computer wirelessly after the algorithm presented in this paper is applied. The first step of the applied algorithm is to find the ROI of the marker in the image using the template matching method. In the ROI, the RANSAC Ellipse fitting algorithm was applied to extract five feature points at sub-pixel resolution. The homography was calculated using extracted feature points and perspective distortion was removed by mapping to a standard plane using the homography. By accumulating the offsets from a previously measured marker point to the currently measured marker point in the standard plane, the displacement can be calculated. In order to verify the performance of the proposed system, nine markers are attached to three buildings for which the proposed algorithm is applied. Whereas existing papers measure only one plane in the range 2.5~25 m, our approach could measure more than nine planes in the range 5~72 m, still providing measurement accuracy (RMS) of 0.05~0.26 mm.


For accurate astronomic and geodetic observations based on radio telescopes, the elevation-dependent deformation of the radio telescopes’ main reflectors should be known. Terrestrial laser scanning has been used for determining the corresponding changes of focal lengths and areal reflector deformations at several occasions before. New in this publication is the situation in which we minimize systematic measurement errors by an improved measurement and data-processing concept: Sampling the main reflector in both faces of the laser scanner and calibrating the laser scanner in situ in a bundle adjustment. This concept is applied to the Onsala Space Observatory 20-m radio telescope: The focal length of the main reflector decreases by 9.6 mm from 85 Terrestrial laser scanners are now widely used in engineering geodesy both for documentation and for deformation monitoring. Deformation analyses of, e.g., cooling towers , tunnelsTerrestrial laser scanning has also been used for determining changes of focal lengths and areal reflector deformations of radio telescopes at several occasions before ,17,18,19The Onsala Space Observatory (OSO) 20-m radio telescope is a mm- and cm-wave antenna with a focal length of about 9 m, located about 50 km south of Goteborg, Sweden  left. ItVLBI measurements employ pairs of radio telescopes to simultaneously observe signals from quasi stellar objects for determining the difference in signal arrival times. The parameters of the baseline between the radio telescopes can then be estimated from the time delay which also depends on the signal paths within the optics of the radio telescopes . Hence, Scanning the main reflector in two opposite cycles so that each part of the main reflector is sampled in two faces .Proving the applicability of TLS  for elevation-dependent deformation analyses of radio telescopes by investigating the measurement’s accuracy in detail .Analyzing the elevation-dependent deformation considering relevant systematic measurement errors based on an improved measurement and data-processing concept in a bundle adjustment .The OSO 20-m telescope’s main reflector has not yet been analyzed for surface deformations. To increase the accuracy of measurements performed by the OSO 20-m radio telescope, the present study, hence, proposes a new concept for an elevation-dependent deformation analysis. Herein, three main points are focused:In consequence, this study proposes several general insights in the deformation analysis of large civil infrastructures as well as in the quality assurance when using TLS for such engineering tasks demanding high accuracy.m of scan points that are based on measuring horizontal angles For the present application, a Leica Scan Station P20 laser scanner was used. In general, a TLS samples the surrounding surface by a large number For analyzing the deformation and movement of the radio telescope’s main reflector, the scans were performed at different elevation angles of the telescope: 85elescope , positioThe support holding the TLS has been designed and manufactured particularly for TLS instruments scanning radio telescopes. It consists of a bracket being attached to the radio telescope’s beam and a flexible spherical hinge . The fleDuring the rotation of the telescope, the hinge was unconstrained while during measurements, a pneumatic break held the scanner in a vertical position. The assumption was that the scanner stays always upside-down due to its weight. Only after the fixation of the hinge, the scanner started its own rotation and measurements assuming a stable position and orientation. As will be analyzed in Spatial resolution: 1.6 mm at 10 m distance. This high point sampling is not necessary for the parameter estimation but it helps at determining spatial correlations in laser scans which is the task of a further study.Spatial coverage: Complete scan of 360Quality level: The Leica Scan Station P20 requires the user to specify a quality level. The larger the quality level, the more points being consecutively measured are averaged to minimize random errors in the measured distances. This moving average most probably leads to a larger correlation between the scan points with unknown error distribution that would have to be accounted for in the deformation analysis. Hence, although a high quality level would indeed increase the precision of the distance measurement, the lowest quality level  was chosen.The following scan settings were chosen for scanning at the proposed elevation angles:Special focus should be led on the horizontal rotation of the laser scanner during a complete scan: Since the area of interest covers more than 180lignment ,12. Consanalysis .These settings led to 14 scans in total, each of the seven elevation angles measured in two cycles. Each point cloud consists of about 570 million points. The atmospheric conditions did not vary noticeably with time during the measurements due to cloudiness: The absolute air temperature was 14.1The scanning geometry is chosen considering angles of incidence of up to 45gated by , can be The panels of the main reflector are bare aluminium with a light gray color but manufactured very smoothly to receive radio signals of small wavelengths. Hence, the intensity of the reflected laser spot and the random errors that are governed by this intensity  have to Systematic errors due to laser scanner misalignment have already been proven to be a limiting factor for deformation analyses. Consequently, they also have to be investigated further see .Before performing the deformation analysis in In the present study, the stability of the laser scanner is also of great importance: Contrary to the usual mounting of a laser scanner on a tripod or a pillar, the laser scanner is fixed to a flexible spherical hinge whose stability has not yet been proven. This is investigated in For the subsequent evaluations of the laser scans’ uncertainty, the laser scans are approximated by a rotational paraboloid representing the main reflector of the radio telescope. This procedure—which is only used in this section to investigate the derived residuals of approximation—will be explained in more detail in The stability of the laser scanner is of particular interest here since its mounting is rather unusual. This is due to two facts: (1) The laser scanner is oriented always upside-down and (2) it is mounted neither on a tripod nor a concrete pillar but to a flexible spherical hinge which is moving itself together with the main reflector.The amount, as well as the orientation where the shift occurs, varies between the individual scans. Thus, the position of this shift on the main reflector also varies. Hence, we cannot claim the main reflector’s surface to produce this bias by an abrupt local deformation. The reason for this bias has rather to be searched in the data acquisition. This assumption can be supported by the fact that the bias only occurs at some of the cycle 1 scans.Instead, the bias can be interpreted as a poor stability of the laser scanner orientation: It only occurs at measurements in cycle 1. These scans were performed directly after the movement of the main reflector around its elevation axis. Hence, when the scanner started its rotations around its vertical axis, the spherical hinge supporting the laser scanner might not have been fixed in its correct position so that the rotation of the scanner forced the hinge to re-orientate until it was in its desired upside-down position. After this re-orientation, the hinge was apparently always stable enough since this shift only occurs in cycle 1 measurements and only at the beginning of these scans.In contrast to this, at elevation angles of 5Systematic errors following from unavoidable misalignment of the TLS can easily outnumber the random errors so that the interpretation of, e.g., deformations, can be totally misleading. This can also be seen in the present study: The observations of the TLS are pre-processed by the manufacturer before made available for the operator. Here, the original measurements are corrected by unknown calibration functions. The calibration parameters used herein are determined during manufacturing; they vary with temperature. Consequently, the remaining errors due to misalignment that we want to estimate here are temperature-dependent and do only represent rest effects that are not handled by the manufacturer’s pre-calibration.Since the mechanical construction of a TLS is complex, there are still different opinions about which calibration parameters to estimate. On the one hand, there are empirical parameters ,26, on tYou cannot measure single scan points repeatedly so that a sophisticated network of reference objects has to be build up for estimating the calibration parameters. Only at optimal networks, the calibration parameters are assumed to be stable.The aim of the laser scanner calibration is the parameterization of the laser scanner’s misalignment which seems to be similar to the calibration of a total station at first glance. Hence, calibration parameters as, e.g., collimation axis error, trunnion axis error and vertical index offset need to be determined. However, the calibration of a terrestrial laser scanner is more complex , mainly In consequence, the present strategies for laser scanner calibration still suffer from the fact that the calibration parameters are only valid in situ ,28,29,30Hence, the parameters describing the potential mechanical misalignment of the laser scanner are estimated as part of the common deformation analysis leading to an in situ self-calibration. This approach has been introduced for the deformation analysis of the Effelsberg 100-m radio telescope’s main reflector by ,18 incluDue to the laser scanner misalignment, the calculation of the cartesian coordinates written in Equation  has to bConsequently, Equation  instead All of these parameters are two-face sensitive; hence, they change their signs between face 1 and face 2. To account for this, the angle parameterization is adapted following : In the In general, a panoramic laser scanner is subject to 18 calibration parameters . This liIn consequence, any deformation analysis should be accompanied by an in situ self-calibration of the laser scanner. By this, the accuracy of the measured horizontal angles The calibration parameters The scanner does not rotate exactly 180It should be noted that the estimation of the calibration parameters goes along with an elimination of a small part of the scan points as can be seen in, e.g., The positions where the intensity is very high (dark blue), the angle of incidence is about 5At angles of incidence from 5At angles of incidence larger than about 10The intensity of the backscattered laser spot governs the precision of the distance measurement . While FThe actual intensity values that are given by the software Cyclone as relative, unit-less numbers between −2000 and 2000 are depicted in urements , this prFor empirically assessing the precision of the distance measurement, the standard deviation of the estimated residuals is used: This standard deviation represents the precision of the distance measurement since (1) the residuals approximately point into the line-of-sight of the laser scanner and (2) the panels are manufactured more precisely than the range noise: The surface accuracy of the panels is specified as 0.14 to 0.22 mm .As a consequence of these investigations, the residuals of approximation are panel-wise averaged in the subsequent deformation analysis: For each of the 120 panels, the scan points sampling it are selected and the mean value of all corresponding residuals is calculated. This averaging helps to reveal local surface deformations by increasing the signal-to-noise ratio: It minimizes random errors and it highlights systematic errors caused by local surface deformations. The result of this panel-wise averaging is shown in One of the main aspects of the present study is the elevation-dependent deformation analysis of the main reflector of the OSO 20-m radio telescope. As stated in The data pre-processing includes the steps of data reduction, object segmentation and outlier removing that have been introduced for an accurate deformation analysis of radio telescopes . To avoiData reduction might be a usual step in TLS point cloud pre-processing—but only aiming at improving the handling of the data memory and processing time ,32,33. OGenerally, object segmentation describes the separation of the object of interest from the surrounding background not being of interest. Therefore, the method of separation is application-specific in most cases. This can range from semantic segmentation  to geomeIn the present case, the object segmentation directly evolves out of the construction of the main reflector: The main reflector does not equal a closed body but consists of 120 solid panels see . The disThe vertex of the main reflector: Here, the feedhorn collecting the electro-magnetic signals and further processing units are located. Hence, points inside a radius of 1 m around the vertex are removed.Gaps between the panels: These outliers have already been eliminated by the object segmentation.Blooming effects that occur at small angles of incidence see also : The intCommon gross errors in the distance measurement that are, amongst others, due to the electronic processing or small anomalies in the surface’s reflectivity: These outliers are removed in a pre-adjustment eliminating points with estimated absolute residuals larger than 7 mm .Outliers can degrade the deformation analysis by either biasing the parameter estimation or by complicating the analysis of local deformations on the main reflector’s surface. Hence, they need to be eliminated. In total, these outliers occur because of different reasons:f, if it is positioned in its normal form where its rotation axis equals the Z-axis of the coordinate system The measured point clouds of the main reflector each consist of x- and y- axis and This is, however, not the case since the main reflector is scanned in the laser scanner’s local coordinate system For estimating the parameters Equation ), the orEquation ) by tranEquation ) and theEquation ).Equations –7) intr intr7) iSimply measuring the object in two faces: By combining both point clouds, all two-face sensitive errors can be minimized.Calibrating the laser scanner in situ: The calibration parameters are estimated along with the deformation parameters.In principle, there could be two strategies:We focus a combination of both strategies for the present application. This can be reasoned by the following: At the elevation angles 85Consequently, we estimate the 7 calibration parameters quations  and 3);;pcalib de: n equals m of scan points is about 22 million. This is because 7 elevation angles were scanned in two cycles but the scans of cycle 1 at elevation angles 85While the calibration parameters  scanner . To imprFor the stochastic model, the covariance matrixtion P20 . For theThis adjustment typically leads to the Gauß-Helmert model (GHM)—also known as general case of adjustment —considervTΣll−1v ,41. The vTΣll−1v ,42 so thvTΣll−1v ,41.The results of the approximation are the estimated parameters The results of the adjustment can be split up into the estimated calibration parameters, the estimated object parameters indicating the global deformation and the post-fit residuals indicating local deformations. Before these are evaluated, the parameter correlations are investigated.Do the two-face measurements improve the separability between object and calibration parameters?Does the bundle adjustment improve the separability between object and calibration parameters?In general, parameter correlations help at investigating the ability to separate estimated parameters from each other. In the present case, two questions are of special interest:If both questions could be answered with ’yes’, the significance of the deformation analysis would increase since the values of the object parameters are less affected by the in situ calibration of the TLS.Concerning the first question, we compare (a) the correlations between the object parameters f and Concerning the second question, we compare the correlations between the calibration parameters and the object parameters considering the different elevation angles (1st to 7th black box from left at bottom in The estimated object parameters are presented in The estimated residuals are relevant for analyzing local deformations of the main reflector’s surface that might concern only single panels or a collection of adjacent panels. These residuals are depicted in For elevation angles of 45The estimated residuals in Scanning in two facesA new measurement concept for deformation analyses of radio telescopes’ main reflectors is proposed based on scanning in two faces to minimize systematic measurement errors due to misalignment of the TLS.Accuracy evaluation of TLS measurementsThe accuracy of the laser scans is evaluated by analyzing the stability of the laser scanner and by assessing the precision of the measured distances. Special focus is led onto the systematic measurement errors due to misalignment of the TLS. These preliminary investigations prove the applicability of laser scanners for the present task.Elevation-dependent deformation analysisFor the deformation analysis, a new concept is presented including the two-faces measurements: It is based on an in situ calibration of the laser scanner in a bundle adjustment including all elevation angles.To increase the accuracy of geodetic and astronometric measurements performed by a radio telescope, its elevation-dependent deformation should be known very accurately. Therefore, the present study presents a new measurement and data-processing concept based on a terrestrial laser scanner, applied to the OSO 20-m radio telescope. In total, three main aspects are handled:Concerning the OSO 20-m radio telescope, focal length variations of 9.6 mm between the elevation angles of 85 22.7 mm . FurtherIn the next steps of data analysis, some general aspects should be considered further: Firstly, the results should be used to improve the VLBI delay model leading to more accurate baseline estimates. First considerations can be found in . Secondl


Crex crex), a nocturnal rail species with innate (non-learned) calls, is able to eavesdrop on the interactions of conspecific males and how this eavesdropping affects subsequent responses by the eavesdropper to territorial intrusion. In the first step, simulated aggressive or neutral interactions between male dyads were presented to a focal male. In the second step, the calls of winning, losing or neutral males from the first step were played within the territory of the focal male. We measured behavioural and vocal responses of focal males. We found that corncrakes eavesdropped on signal exchange between rivals. Males often began responding to distant aggressive interactions during the eavesdropping phase, and they responded strongly during the intrusion phase of the experiments. The response was significantly weaker to playback of males from neutral interactions than to those involved in aggressive interactions, and we found no differences between the responses to Winners and Losers entering a focal male territory.The behaviour of most animals has evolved in a communication network environment, in which signals produced by senders are perceived by many intended and unintended receivers. In this study, we tested whether the corncrake ( Parus major) eavesdrop on vocal interactions between males to choose the best partners for extra-pair copulation [Poecille atricapillus) whose partners lost in a vocal interaction with an opponent had fewer offspring than females with winning partners [Luscinia megarhynchos), males are able to recognize the motivation of two interacting rivals and respond more strongly to aggression [Eudyptula minor) [Communication involves a sender using signals to influence the behaviour of a receiver , and livpulation , 20, whipulation , 22. Fempartners , 24, 25,gression . These sa minor) . Males oThe evolution of acoustic communication in birds was a complex process resulting in both differences in structures responsible for vocal production  among taxa and diversity of vocalization complexity , 4, 28. Crex crex) is an ideal non-learning bird species for the study of social eavesdropping. This nocturnal, cryptic species communicates almost exclusively through the acoustic channel [The corncrake (nication), and malnication).The terrnication). It consnication)) that chnication). Males snication), 34. Befnication). Soft canication). The sennication). Hence, nication), 34. Mornication), 37, 38)In this study, we used four loudspeakers to imitate natural interactions between two males in a two-part experimental design. In the first part, we simulated a male-male interaction ending with a clear Winner and Loser or a neutral outcome with no obvious victor at a distance from a focal individual. The Winner always stayed after the end of simulated interaction while the Loser become silent and flew away. In the second part, we simulated an intrusion into the territory of a focal male by playing back the call of the Winner or Loser or a randomly chosen male from the neutral interaction. We predicted that males using social information adjust their behaviour depending on the dominance status of an eavesdropped male to reduce the cost of protecting their territory; in particular, they should adjust the strength of their response in relation to the individual (Winner or Loser of the preceding interaction) entering the territory. Finally, we compared the strength of the responses of males after eavesdropping to the regular responses of males to strangers and neighbours that were tested in earlier experiments . The aimth May through 16th June, 2013–2015. The study area (ca. 55 km2) consisted of meadows, marshes and arable fields, throughout which corncrakes were commonly but irregularly distributed. The basic parameters of abundance and habitat preference are well known from earlier studies [The study was carried out in the Upper Nurzec River Valley in Northeast Poland  from the 19 studies . The stu studies , 38. TheExperiments were carried out between 2200 and 0230 h local time. Before each experiment, the loudspeakers were placed 0.20 m above the ground at a distance of 100 m from the calling subject. All experiments were conducted within an acoustic location system that consisted of an array of 4 omnidirectional microphones , each of which was connected with a wireless signal transmitter (Sennheiser SKP 3000). Radio signals were received by a Sennheiser QUADPACK QP3041 sound receiver  and finally recorded with an Edirol R-4 Pro 4-channel Portable Recorder and Wave Editor . Microphones were fixed approximately 1.2 m above the ground. The main idea of the experiment was to simulate natural aggressive or non-aggressive interactions between dyads of stranger males, on which the subject male could eavesdrop. Then, we simulated an invasion into the territory of the focal male with a playback of the calls of one of the males involved in the simulated interaction. We performed three treatments with different groups of males: Winner (W), Loser (L), and Control (C), and each treatment consisted of (1) eavesdropping and (2) intrusion phases, which were always carried out in the same order. During eavesdropping (240 s), focal males were able to listen to interactions between male dyads that were simulated via a set of four loudspeakers located 100 m away. The eavesdropping phases of the Winner and Loser treatments were exactly the same length. At the beginning, broadcast calls of simulated males were played back for 120 s from two loudspeakers separated by 10 m. Then, we simulated males approaching each other by silencing the first pair of loudspeakers and beginning playback from a second pair placed only 2 m apart for the next 120 s. At the end of the simulation of the W and L treatments, we played back soft calls, sounds of fight, sounds of flying away, and the final 60 seconds of broadcast calls from the Winner of the simulated conflict . For theThe calls used in the experiments were recorded from the local population. In selecting calls for playback preparation, the priorities were high-quality recordings and the use of non-neighbour calls. The rhythm of a call is one of the most important factors affecting the response of rivals , since iThe strong response of male corncrakes to playback is well known . TypicalTo analyse the differences in the response between the experiments we used Fisher’s exact tests. The simple response measures  were treated as binary variables. This approach, together with a histogram of the frequency of particular response categories, provided a good overview of the behaviour of the birds during the experiments . In moreWe tested a total of 75 males. Twenty-six received the Winner treatment; 22 received the Loser treatment; and 27 received the Control.z = -5.61, p< 0.001); it was higher during treatment W  and treatment L  than during the Control . We found no significant effect of the call rhythm before the experiment, day or hour on the RSI . During the eavesdropping phase, 10 males attacked the speaker under the treatments (W and L combined), but none attacked under the Control. We found no significant difference in the number of attacks between those groups (W+L and Control) of males .We found that focal males often started responding to simulated interactions during the eavesdropping phase of the experiment, especially in the W and L treatments. A high proportion of the males stopped calling (21%), approached the speakers (40%), and some even finished with soft calls (14%) and physical attacks on the speakers (13%) before the start of the intrusion phase . We founz = -2.27, p< 0.023) and was slightly higher in treatment W  and treatment L  than in the Control . All the other analysed models exhibited a poorer fit and did not indicate significance effects of call rhythm before the experiment, day or hour . We also found that focal males conducted significantly more attacks  on the speaker when we invaded the territory with Winner  or Loser calls  compared to the Control . The best model included the predictors of treatment effect  and call rhythm before the playback . The relationship between the call rhythm before the experiment and the number of attacks during the intrusion phase had quadratic characteristics. The strongest response, as indicated by the number of attacks, was given by males who signaled with a rhythm close to the one used for playbacks . As there is tremendous vocal diversity among birds as well as different learning patterns and cognitive abilities, we may expect that social eavesdropping evolved under various selective pressures. The purpose of this study was to broaden the knowledge about social eavesdropping through experimentation with a model, non-learning, bird species, for which acoustic communication in territorial defence is crucial because the usefulness of other communication channels is poor due to its nocturnal lifestyle. In addition, corncrakes behaviour in aggressive interaction is very straightforward and relatively easy to describe. Males either attack or escape from aggressors. Our results revealed the existence of eavesdropping in male corncrakes. We found that these birds pay close attention to the vocal interactions occurring within the proximity of their territories. Males were more likely to initiate a response and showed a stronger response when eavesdropping on aggressive interactions compared to eavesdropping on neutral counter-calling. An aggressive interaction appeared to be such a strong stimulus that some males approached the speaker and attacked it as early as the eavesdropping phase. Males usually respond to playbacks of a call (of a single intruder) if the distance to the speaker is much closer (±20–30 m) than in our experiments (100 m) [Determining how animals settle conflicts is fundamental to understanding the evolution of resource defence behaviour , and pre (100 m) , 47, 38.Most of the bird species studied with respect to social eavesdropping have been songbirds whose learning abilities are well known , especiaLuscinia megarhynchos). Males of this species sing extensively at night, so their decisions concerning territorial defence likely rely solely on acoustical perception [Paroaria gularis[The results of our study are comparable  to earlier research on the common nightingale  ability, potential, motivation and experience of males. Earlier studies of corncrakes revealed that they signal their fighting ability through the rhythm of their broadcast call, which is an arbitrary character whose honesty is maintained by the retaliation rule , 34. It We compared the use of soft song and speaker attacks in this study with the results of earlier experiments testing (with positive results) the neighbour-stranger discrimination ability of corncrakes . For thiWe found that males of a non-learning, nocturnal rail species eavesdrop on signal exchange between rivals outside their territories. Focal males often started responding to distant rival interactions during the eavesdropping phase, which was not observed if playback of a single male was presented outside of a territory. This suggests that eavesdropping behaviour acts as an early warning system for threats to territorial integrity. We also found that, as a rule, males responded strongly in the intrusion phase of the experiments, but the response to playback of males from the Control  was significantly weaker than that to both treatment groups (aggressive interaction). We found no support for a difference in the response to Winners and Losers of simulated interactions, and we also found that the strongest response, as represented by the number of attacks, was by males who called with a rhythm that was comparable to the rhythm of the playback . To sum up, our study revealed that male corncrakes eavesdrop on the signal exchange between conspecifics outside their territories and that the strongest factor affecting their response was the character of the eavesdropped interaction . We did not find strong support for different responses to Winners and Losers, which is likely due to a territory ownership strategy of responding strongly to unknown males that took part in an earlier aggressive encounter.S1 Tablebold.Proportions are indicated as number of experiments with soft calls/number of all experiments, and this study vs NSD study. Significantly larger proportions in (PDF)Click here for additional data file.S2 Tablebold.Proportions are indicated as number of experiments with attacks/number of all experiments, and this study vs NSD study. Significantly larger proportions in (PDF)Click here for additional data file.


Fibromyalgia syndrome (FMS) is a chronic, complex, and heterogeneous disorder of still poorly understood etiopathophysiology associated with important musculoskeletal widespread pain, fatigue, non-restorative sleep, and mood disturbances. It is estimated to afflict 2–3% of the worldwide population, with clean prevalence among women. The objective of this paper is to propose a novel treatment for symptomatic remission of FMS, grounded in biochemistry and consisting in the withdrawal from the diet of molecules that can indirectly trigger the symptoms. The hypothesis develops from the evidence that low serotonin levels are involved in FMS. Serotonin is synthesized starting from the essential amino acid tryptophan. The presence of non-absorbed molecules in the gut, primarily fructose, reduces tryptophan absorption. Low tryptophan absorption leads to low serotonin synthesis that triggers FMS symptoms. Moreover not-absorbed sugars could also produce a microbiota deterioration activating a positive feedback loop: the increasing microbiota deterioration reduces the functionality of absorption both of fructose and tryptophan in the gut, entering a vicious circle. The therapeutic idea is to sustain serotonin synthesis allowing the proper tryptophan absorption. The core of the cure treatment is the exclusion from the diet of some carbohydrates and the marked reduction of some others. The main target is the limitation of total dietary fructose as marked as possible. It could be an effective strategy to get the remission of symptoms acting on the impaired biochemical pathways. The straying from the treatment is expected to cause the reappear of the symptoms. PharmacThe objective of this paper is to propose a novel treatment for the remission of symptoms of FMS, clearing up the logical steps that support the idea addressing its foundations grounded in biochemistry. An hypothesis of the primary cause of FMS is also proposed.2The apparent heterogeneity of the symptoms is the key information for catching the core of FMS. It has to be considered a disease as a whole. It is correctly defined, indeed, a syndrome. Looking at the common cause that connects all the symptoms, instead of searching for a managing strategy of each one apart, is the effective way to understand the impaired biological pathways and to built a remission cure.low 5-HT levels are involved in FMS , 12;l-tryptophan (Trp)  ;the presence of non-absorbed molecules in the gut, primarily fructose, reduces Trp absorption ;low Trp absorption reduces Trp bioavailability;low Trp levels reduces 5-HT biosynthesis;low 5-HT levels trigger FMS symptoms.The common denominator among all the symptoms is serotonin . This is the starting point of the deductive reasoning that led to investigate biochemical and physiological mechanisms that are the cure foundations. In short, the logical steps that constitute the rational of the idea are the following:The presence of non-absorbed fructose could also produce a microbiota deterioration activating a positive feedback loop: the increasing microbiota deterioration reduces the functionality of the absorption both of fructose and Trp in the gut, entering a vicious circle. Moreover, it could affect the absorption of other essential amino acid, as Maillard reaction is not restricted to Trp, and the absorption of some mineral salts . It coul33.1Trp is an essential amino acid for humans: its availability as a substrate for biosynthesis relies on dietary intake . Moreovel-type amino acid transporter”  is a hexose sugar naturally present in fruit and honey. In the last decades its consumption is making an increasing contribution to the Western diet since it is used in industrial products as sweetener in the form of high fructose corn syrup  are the consequence” . Intereslerance” . The advlerance” ; the conlerance” ; the expMost dietary fructose is completely absorbed in normal subjects, when ingested in small quantities . HoweverThe negative implication of fructose malabsorption may also be responsible for impairment in mineral salt absorption. An interesting study reports association between low serum zinc concentrations and fructose malabsorbers . GastroiSymptoms of fructose malabsorption may be exacerbated by the sugar alcohol sorbitol : in fact4.1.2The method of acute tryptophan depletion (ATD) reduces Trp availability as substrate for 5-HT synthesis . PositroIt was reported that the depletion of 5-HT precursor Trp by dietary exclusion of this amino acid has caused clinical deterioration of patients with major depressive syndrome . LedochoSimilar results were obtained in patients with fructose intolerance  and the 4.1.3The formation of a fructose–Trp complex  was prevThe chemical basis of these hypotheses are the well-known Maillard reactions that occurs between sugars and amino groups. Reducing sugar, fructose in primis, is involved in these non-enzymatic reactions with proteins: decreased protein quality due to the loss of amino acid residues and decreased protein digestibility are the consequences . MaillarIn vitro data demonstrate that the rate of protein cross-linking in the presence of fructose is 10 times greater than in the presence of glucose , fresh fruit that naturally contains fructose, honey, soft drink, and beverages containing HFCS and saccharose , 34, 47.Lactose might have the same consequences of fructose in the gut, especially if the enzyme lactase is deficient.per se to Trp malabsorption and/or microbiota deterioration can be supposed less relevant, in fact the deficiency of the enzyme sucrase is a very rare congenital condition except in Greenland  are not suggested in any way, as their intake has potential for important side effects by themselves or due to the interaction with serotonergic drugs, up to life-threatening effects related to serotonin syndrome .Suggested food containing Trp are: meat, eggs, fish, rice, potatoes, dark chocolate, and walnuts.A further note concerns monosodium glutamate (MSG) and aspartame: their withdrawal from the diet is suggested too. MSG naturally exerts excitatory action in both the central  and periThe evaluation of this restrictive diet as possibly inappropriate from a nutritional perspective must be properly considered. The withdrawal of fructose-containing food could lead to a concomitant reduction of vitamin and mineral salt intake. Periodic blood exams must be considered to evaluate their levels: vitamin and mineral salt supplements must be considered to address deficiencies already present and to prevent possible ones during and after the protocol implementation.5.4The Marked difference among sexes in the rate of 5-HT synthesis  may be tNevertheless, some other considerations can be made. The association between decreased serum Trp concentrations and sugar (fructose and lactose) malabsorption was observed in experimental studies significant only in women. This could be a consequence of the greater activity of the hepatic enzyme TDO, which is estrogen dependent , 40. In Stress may also provoke similar effect activating the same biochemical pathway, contributing in the exacerbation of patient conditions: besides estrogens, indeed, TDO is inducible by Trp itself and glucocorticoids . The gluLast but not least, since the expression of GLUT5 occurs primarily in the small intestine, but lower levels are also expressed in the cells of testes, skeletal muscle , and adi6This paper presents the hypothesis grounded in biochemistry of a novel treatment for the remission of FMS symptoms related to the hypothesis that a gastrointestinal malabsorption has a central role as a primarily cause of FMS and that it is mainly due to fructose.The novel remission treatment is a strict dietary strategy. It is low cost and drug free, so intrinsically not prone to collateral effects related to drug intake . The corGiven its foundations, the cure is expected to obtain a remission not a final recovery. The straying from the treatment is expected to cause the reappearance of the symptoms.This paper suggests only Trp intake through diet, maximizing its absorption potential, avoiding as much as possible its co-ingestion with fructose-containing food, in order to guarantee its availability for 5-HT synthesis, maximizing the positive effects of its nutritional properties. The role of some other sugars should be taken into account, as they could determine the same consequences of fructose on Trp absorption.The remission is a short-term result and is related to be or not on diet guidelines: small indiscretions might have great potential for the return of symptoms in severe conditions. The effect on reducing microbiota deterioration, instead, could be a long-term result, but experimental data from long-term studies will be necessary.Finally, the crucial role of 5-HT in the body, 5-HT interaction with immune system, the possible interference of fructose with the absorption of essential amino acid and other nutrients and the possible role of non-absorbed fructose in the microbiota deterioration suggest that fructose malabsorption may have really more relevant effects on human health then considered up to now.The author confirms being the sole contributor of this work: developed the hypothesis, researched, wrote the paper, and approved it for publication.The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Wireless sensor networks (WSNs) are widely applied in industrial application with the rapid development of Industry 4.0. Combining with centralized cloud platform, the enormous computational power is provided for data analysis, such as strategy control and policy making. However, the data analysis and mining will bring the issue of privacy leakage since sensors will collect varieties of data including sensitive location information of monitored objects. Differential privacy is a novel technique that can prevent compromising single record benefits. Geospatial data can be indexed by a tree structure; however, existing differentially private release methods pay no attention to the concrete analysis about the partition granularity of data domains. Based on the overall analysis of noise error and non-uniformity error, this paper proposes a data domain partitioning model, which is more accurate to choose the grid size. A uniform grid release method is put forward based on this model. In order to further reduce the errors, similar cells are merged, and then noise is added into the merged cells. Results show that our method significantly improves the query accuracy compared with other existing methods. Recent years have witnessed the rapid development of the industrial wireless sensor networks (IWSNs), which have been introduced into the industry area to meet requirements of higher flexibility and market share, and IWSNs are becoming the key and fundamental technology of Industry 4.0 . In the The Location information is called geospatial data . For exaCompared with wired networks, IWSNs have a higher possibility of privacy leaks when they integrate with cloud computing and big data technologies. Consequently, effective privacy-preserving technologies are needed in IWSNs. The work in  analyseskd-tree is proposed to enhance the utility of released data. However, these works have not analyzed optimal partition granularity of data domains, so how to choose the appropriate tree depth or partition granularity is the key point for data decomposition strategy.In order to improve the utility of released geospatial data, a number of data decomposition methods based on tree structure were proposed . In 26,,28,29, aTo the best of our knowledge, the work in  first usk.We propose a novel granularity partitioning model of data domain, which is effective to balance the noise error and the non-uniformity error. The partition granularity is proportional to the area of data domain, privacy budget and coefficient We adopt a cells merging strategy based on bucket sort, which groups all the similar cells of data domain into a partition, in order to decrease the noise added to each cell. This merging strategy further raises the accuracy of query.We conduct evaluations using two real-world datasets to verify the effectiveness of the granularity partitioning model and the similar cells merging strategy, and results show that the proposed approach has better query accuracy and enhances the utility of released data.The contributions of this paper are as follows:The rest of this paper is organized as follows: The work in  studies m. The finer value of m implies a fewer non-uniformity error.In order to enhance the utility of perturbed data, PSD based on tree structure is adopted . The PSDkd-tree structure, Xiao et al. ,,7], UgriQ. Mgrid further enhances the query accuracy by the similar cells merging strategy, which merges the similar cells into a partition to decrease the added noise to each cell. Experimental results verify the effectiveness of the granularity partitioning model and the similar cells merging strategy.Note that the experimental results of UG outperform the results of AG in As shown in Q is a rectangle, which is closer to the requirement of actual queries. Ugrid and Mgrid are proposed based on this model and are validated through two real world datasets. Experimental results show that Mgrid has a good utility and query accuracy.The location information of monitored objects is an important privacy attribute in IWSNs, which has become a significant research direction. To protect node location privacy and enhance the utility of perturbed data, we propose a novel granularity partitioning model based on the overall analysis of two types of errors. This model considers that the shape of query As for future work, we will continue to improve the granularity partitioning model and make the model to be in better accordance with the self-characteristics of datasets. For instance, using area and point count two factors to construct the model. In addition, we will explore the distributed application for geospatial datasets—for example, multiserver differentially private data release.


Emergency resource is important for people evacuation and property rescue when accident occurs. The relief efforts could be promoted by a reasonable emergency resource allocation schedule in advance. As the marine environment is complicated and changeful, the place, type, severity of maritime accident is uncertain and stochastic, bringing about dynamic demand of emergency resource. Considering dynamic demand, how to make a reasonable emergency resource allocation schedule is challenging. The key problem is to determine the optimal stock of emergency resource for supplier centers to improve relief efforts. This paper studies the dynamic demand, and which is defined as a set. Then a maritime emergency resource allocation model with uncertain data is presented. Afterwards, a robust approach is developed and used to make sure that the resource allocation schedule performs well with dynamic demand. Finally, a case study shows that the proposed methodology is feasible in maritime emergency resource allocation. The findings could help emergency manager to schedule the emergency resource allocation more flexibly in terms of dynamic demand. Maritime safety has attracted an increasing attention in recent decades. Maritime emergencies occur frequently, causing great damage to environment and society. For example, the accident that Oriental Star wrecked on June 1st, 2015, has raised the worldwide shock. Maritime emergency logistics management has emerged as a globally concerned theme as maritime accidents ubiquitously occur around the world. In practice, the difficulty of relief-demand management is rooted in the uncertainties, J0 = |M||I|. Where, M denotes the number of emergency resource types, I denotes the number of disaster areas. The role of the parameter Γ0 is to adjust the robustness of the whole uncertain demand. Accordingly, for mi ∈ J0, the quantity of emergency resource uncertain demand is ⌊Γ0⌋, with a uncertain demand changed by In order to measure the robustness of the objectives, we introduce a parameter ΓTherefore, the objectives of the model  becomes:m emergency resource, we introduce the parameter Γm, include but not limited to integer, taking value in the interval, Jm = |I|, Γ0 = Γ1 + Γ2 + … + Γm. The parameter Γm is to adjust the robustness of every uncertain demand. Accordingly, for mi ∈ Jm, the quantity of type m emergency resource uncertain demand is ⌊Γm⌋, with a uncertain demand changed by Likewise, In terms of the type The second constraint of the model  becomes:In order to reformulate the model as a linear optimization, We intend to implement the methodology of robust counterpart proposed in Ben-Tal and DimitGiven the following linear optimization model:Equals the dual of problem :minΓ0γ+By strong duality, the linear optimization model  is equalComparing the model after formulation with the original model, in order to solve the decision variables, many new parameters raise up. The parameters By 2016, there are 476 terminals in Shandong maritime area in China (simplified as Shandong), among these, 214 terminals are more than ten thousand tons.The terminals distribution of different grade is shown in The risk indicator statistics in Shandong can be shown during 2012–2014, As shown in There are 87 maritime accidents in Shandong. Find out the location coordinates of the maritime accidents, depicted by Supporting Information According to Tables Put the standard value of indicator as shown in L and R  Reliability analysis of robust optimization solutionAs the It can be seen that, under the dynamic demand condition, when the robust control parameter is more than 5, the reliability of solution is above 80%, and the robust optimization solution can guarantee the effective probability of the resource allocation model. The reliability of the certain allocation is the worst, which can not response to the change of the dynamic demand of the disaster area flexible.(2) Comparison of robust optimal scheme and definite schemeIt’s easy to find that, from Tables (3) Analysis of robust optimal allocationThe more conservative the decision maker attitude is in the face of the demand disturbance, that is, the greater value of the robust control parameter Γ, the greater of the total time and loss of the robust optimized scheme. Compared with the most conservative oil dispersant allocation scheme, when the demand disturbance level is 5%, 10% and 20%, the robust control parameter Γ is 1–7,the proportion of total time and loss saving is shown in Figs As is shown in Figs (4) The total quantity of oil dispenserThe total optimal reserves of the oil dispenser in the Shandong maritime area is the total stock of the oil dispenser in all supplier center. Under the condition that the demand disturbance is 5%, 10% and 20%, the optimal arrangement of the oil dispersant is optimized. The trend that the total quantity of oil dispenser changing with the robust control parameters is shown in With the increase of the demand disturbance, in order to cope with the higher level of demand disturbance, the total quantity of oil spill dispersant is obviously increased. However, the variation law between the total quantity of the oil spill dispersant with the robust control parameters is not obvious. Due to the data characteristics of the dynamic demand distribution and the transportation time of the oil spill dispersant configuration robust optimization model, the stability of the oil spill dispersant configuration system is strong, and the total configuration loss and the minimum time can be realized when the total quantity of the allocation is basically stable. When the demand disturbance level is 5%, 10% and 20%, The total quantity of oil dispersive fluctuated around 503,516,562 tons generally.Based on the above analysis of the robust optimization scheme of the oil dispersant in Shandong maritime area, we can get the following findings.(1) The three important emergency resource supplier centers, that is Yantai, Weihai and Qingdao, are located in the middle of Shandong sea area. The location advantage is obvious, with the average distance is rather short to each accident area. So the reserve stocks of them are high. The robust optimized oil dispersant allocation scheme is reasonable, with the large emergency resource supplier center playing a leading role, the small emergency resource supplier center playing an auxiliary role. The result is in accordance with the actual allocation rules of emergency resources in China.(2) Compared with the certain emergency resource allocation scheme, the robust optimal allocation scheme can cope with the demand disturbance, the reliability is strong and the optimization scheme is rigorous. Compared with the most conservative emergency resource allocation scheme, the robust optimal allocation scheme is more optimal in total loss and time saving, it is significant for the application in practical.(3) With the increase of demand disturbance level, in order to response to the high level of demand disturbance, the additional resources to be allocated is also increased, However, the variation law between the total quantity of the oil spill dispersant with the robust control parameters is not obvious.(4) The total quantity of the spill dispersant is not positively correlated with the allocation effectiveness. Robust control parameter Γ is the indicator measuring the conservation of decision maker. The more conservative of the decision maker, the stronger the reliability of the emergency resource allocation scheme, the weaker of the emergency resource allocation scheme.Therefore, the decision makers should determine the reasonable robust control parameters according to their risk preference, seeking for balance between the robustness of the allocation scheme and the risk tolerance.This paper studies the dynamic demand, and define the dynamic demand with uncertain set. Then a maritime emergency resource allocation with uncertain data is presented. Afterwards, a robust approach is developed and used to make sure that the resource allocation schedule performs well when the data changes. At last a case study is given, we flexibly adjust the level of conservatism of the robust solutions in terms of probabilistic bounds of constraint violations, and draw some interesting conclusions.(1) The maritime dynamic demand analysis is divided into three stages, dynamic demand forecasting, disaster area grouping and dynamic demand distribution. An efficient method is proposed in disaster grouping, combining the K-means clustering method with minimum circle coverage, overcoming the blindness of the traditional K-means clustering method and the initial clustering center randomly selected method.(2) Considering the dynamic demand of maritime emergency resource, a robust optimization model is built up for emergency resource allocation. By the model solution, the optimal stock of emergency resource is determined for supplier centers according to the risk preference and the demand disturbance given by decision makers before disaster occurrence.(3) The case study shows that, compared with the certain emergency resource allocation scheme, the robust optimal allocation scheme could cope with the demand disturbance. The more conservative of decision maker, the stronger the reliability of the emergency resource allocation scheme. However, the total quantity of the emergency resource is not positively correlated with the allocation effectiveness.The proposed methodology is feasible in maritime emergency resource allocation. The findings could help emergency manager schedule the emergency resource allocation flexibly in terms of dynamic demand, regarding to their risk preferences.Nevertheless, there is still a great potential for improving the study of maritime emergency resource allocation. Firstly, the dynamic demand forecasting approach is limited to the some type of maritime emergency resource, not covering all kind of emergency resource. Secondly, the transportation time for emergency resource may change due to the maritime environment. Furthermore, the algorithm for the model solving is designed by matlab, the more advanced technology can be incorporated. The further study is particular important to carry out the ultimate goals of maritime emergency logistics management.S1 AppendixS1 Appendix presents the derivation process of the robust optimization solution reliability.(DOCX)Click here for additional data file.S2 AppendixS2 Appendix list the details of the maritime accidents in Shandong maritime region, including the time, number of casualties, number of damaged ships for period 2011–2015.(DOCX)Click here for additional data file.