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In this paper, a semi-analytical technique based on Taylor's series method namely DTM has been used to solve the differential equation which governs the motion of three types of annular FGM plates. The differential equation has been obtained using Hamilton principle and classical plate theory. The mechanical properties of the plate (Young's modulus and density) are considered to be graded in thickness direction and vary following the power-law. The behaviour of volume fraction index and radii ratio has been investigated onto first three modes of frequency parameter for all three plates. Moreover, the novelty of this paper is the application of the versatile technique DTM to study the effect of radii ratio and volume fraction index on three different types of annular FGM plates. A comparison has been made between the obtained numerical results and the results are available in the literature. A good agreement of the results verifies the accuracy of the present technique. Three-dimensional mode shapes for all three plates are also presented. [ABSTRACT FROM AUTHOR]

In this study, GIS technology was used for modelization and quantification research on historical geographic issues to provide a new research approach and technical route for the study on various crop transmission pathways and historical geographic issues such as material and cultural diffusion. In order to explore the transmission path and diffusion process of corn after its entry into China, a digital ground model of corn transmission in China was established based on the earliest recorded literature and time in various parts of China. Quantitative and model analysis methods were used to study the starting point, direction, main line, and expansion speed of corn transmission in China, and explore the relationship between its diffusion area and population growth since the late Ming Dynasty. The results showed that during the Jiajing period of the Ming Dynasty, corn was introduced to China and formed four independent sources of transmission in western Gansu(1522), southeastern Yunnan (1563), southeastern Guangxi(1564), and eastern Fujian(1545), spreading along eight routes to the whole country. The spread of corn in China was mainly along land transportation routes, and the promotion of corn dissemination by official roads and highways in the Qing Dynasty was significant. However, in the southwestern region of China, due to complex terrain and inconvenient land transportation, the spread of corn mainly extended along river valleys. Since the Qing Dynasty, corn had been rapidly spread and cultivated in China, and the population in China had grown rapidly. The two had shown a significant positive correlation. The widespread introduction of corn was one of the reasons for the rapid population growth in China from the early Qing Dynasty to 1950. [ABSTRACT FROM AUTHOR]

Remote sensing (RS) techniques are essential for studying hazardous landslide events because they capture information and monitor sites at scale. They enable analyzing causes and impacts of ongoing events for disaster management. There has been a plethora of work in the literature mostly discussing (1) applications to detect, monitor, and predict landslides using various instruments and image analysis techniques, (2) methodological mechanics in using optical and microwave sensing, and (3) quantification of surface geological and geotechnical changes using 2D images. Recently, studies have shown that the degree of hazard is mostly influenced by speed, type, and volume of surface deformation. Despite available techniques to process lidar and image/radar-derived 3D geometry, prior works mostly focus on using 2D images, which generally lack details on the 3D aspects of assessment. Thus, assessing the 3D geometry of terrain using elevation/depth information is crucial to determine its cover, geometry, and 3D displacements. In this review, we focus on 3D landslide analysis using RS data. We include (1) a discussion on sources, types, benefits, and limitations of 3D data, (2) the recent processing methods, including conventional, fusion-based, and artificial intelligence (AI)-based methods, and (3) the latest applications. [ABSTRACT FROM AUTHOR]

Airborne Laser Scanning (ALS) point cloud classification in ground and non-ground points can be accurately performed using various algorithms, which rely on a range of information, including signal analysis, intensity, amplitude, echo width, and return number, often focusing on the last return. With its high point density and the vast majority of points (approximately 99%) measured with the first return, filtering LiDAR-UAS data proves to be a more challenging task when compared to ALS point clouds. Various algorithms have been proposed in the scientific literature to differentiate ground points from non-ground points. Each of these algorithms has advantages and disadvantages, depending on the specific terrain characteristics. The aim of this research is to obtain an enhanced Digital Terrain Model (DTM) based on LiDAR-UAS data and to qualitatively and quantitatively compare three filtering approaches, i.e., hierarchical robust, volume-based, and cloth simulation, on a complex terrain study area. For this purpose, two flights over a residential area of about 7.2 ha were taken at 60 m and 100 m, with a DJI Matrice 300 RTK UAS, equipped with a Geosun GS-130X LiDAR sensor. The vertical and horizontal accuracy of the LiDAR-UAS point cloud, obtained via PPK trajectory processing, was tested using Check Points (ChPs) and manually extracted features. A combined approach for ground point classification is proposed, using the results from a hierarchic robust filter and applying an 80% slope condition for the volume-based filtering result. The proposed method has the advantage of representing with accuracy man-made structures and sudden slope changes, improving the overall accuracy of the DTMs by 40% with respect to the hierarchical robust filtering algorithm in the case of a 60 m flight height and by 28% in the case of a 100 m flight height when validated against 985 ChPs. [ABSTRACT FROM AUTHOR]

The popularity of sports and recreational receivers of the global navigation satellite systems is steadily increasing and provides athletes, coaches, and scientists with a wealth of information on movement occurring both horizontally and vertically. Under mountainous conditions, considering the effort put in by the athlete as well as their safety, the elevation parameter appears to be particularly relevant. The aim of the study was to propose a methodology for assessing sports receivers in terms of their determination of the elevation component based on digital elevation models while paying attention to the appropriate measures for testing these devices. The methodology was applied for wrist-worn global navigation satellite systems' receivers used by the participants of an uphill running event. In terms of elevation determination, the most accurate three receivers (same model) were those supported by the barometric altimeter, in which the Root Mean Square result obtained ranged from 3.6 to 4.1 m. The majority of receivers underestimated the total elevation gain, the mean value of which was −3.8%, which does not appear to be affected by the reception of two global navigation satellite systems or the use of a barometric altimeter. The error characteristics were common within the group of receivers of a particular manufacturer. [ABSTRACT FROM AUTHOR]

AbstractSemi-numerical methods hold significant value due to their efficiency in time-consuming calculations. Accordingly, this article proposes an effective strategy to derive the vibration parameters of cylindrical shells (CSs) with cutout utilizing a semi-analytical approach entitled differential transform method (DTM). To achieve this, the governing equations of motion are first introduced based on Sander’s theory of shells. These equations give rise to a coupled system of linear ordinary differential equations, which pose a challenge in solving the eigenvalue problem. It should be emphasized that the classical version of the differential transform method could not be directly applied to solve the eigenvalue problem related to the above-mentioned coupled differential equation. An innovative technique is employed and discussed in the paper to remedy these difficulties, which could be widely used in similar problems. As a result, the natural frequencies and mode shapes of some CSs with cutouts, various internal angles, and diverse material characteristics are attained. The outcomes undergo validation through the hybrid finite element method, and the proposed method’s accuracy is rigorously proved. In conclusion, the proposed DTM provides an efficient solution to the eigenvalue problem of coupled differential equations and offers a valuable tool for obtaining accurate vibration parameters of CSs. [ABSTRACT FROM AUTHOR]

Significant increase of numerous applications in engineering, biological and industrial purpose as metallic extrusion motivated this communication. This paper proposes unique computational procedure is Method of Differential Transforms (DTM) to get an exact solution for electrified conducting fluid over a semi-porous cylinder in an impermeable cylinder with effects of Joule heating and convection term. A key finding of study reports the different dimensionless parameters influences the variations in velocity and heat transport on the fluid flow are presented graphically. The graph reveals an interesting result of Nusselt number, Skin-friction and stream lines elucidates the flow characteristics. A qualitative agreement is found in the present paper and are well matched with earlier work. [ABSTRACT FROM AUTHOR]

Abstract The thermoelastic time-dependent creep progress of a rotating annular plate with nonuniform thickness made of functionally graded piezoelectric material considering convection heat transfer and solar radiation was investigated. The nonlinear differential equation of heat transfer considering conduction, convection, and solar radiation was solved using the differential transformation method. Then, the differential equation of equilibrium for the annular plate containing creep strains was derived. Firstly, the differential equation was solved analytically for the zero time . Then, the stress and strain rates were achieved using Norton’s law with Prandtl–Reuss equations. Finally, the time-dependent creep stresses and deformation redistributions were obtained employing an iterative method. [ABSTRACT FROM AUTHOR]

The aim of our work is to develop a methodology to identify the areas most prone to natural rockfall retention through the integrated use of remote sensing data. The area chosen as a case study is located in Campania (Italy) nearby Mount San Liberatore. In this area, which is itself geomorphologically predisposed to landslide risk, there are several rockfall risk hotspots, so defined because of the high exposed value constituted by an articulated infrastructure network located along the northwest slope of the mountain. The area is largely covered by dense vegetation, of which holm oak is the most representative type, characterized by a taproot apparatus that, giving it strength and stability, makes it an ideal tree for slope protection. Based on high-resolution multispectral satellite images, vegetation indices (VIs) were calculated to estimate health status, approximate age, average height, robustness, and vigor. Morphometric parameters suitable for describing slope dynamics were also calculated, derived from LiDAR data. The classification of areas with similar characteristics was carried out using Self-Organizing Maps. The results made it possible to identify all those areas where there is a greater contribution of protective forests in the mitigation of rockfall risk and, consequently, to identify areas to carry out a combined strengthening of protective actions. [ABSTRACT FROM AUTHOR]

Fins are utilized to considerably increase the surface area available for heat emission between a heat source and the surrounding fluid. In this study, radial annular fins are considered to investigate the rate of heat emission from the surface to the surroundings. The effects of a ternary nanofluid, magnetic field, permeable medium and thermal radiation are considered to formulate the nonlinear ordinary differential equation. The differential transformation method, one of the most efficient approaches, has been used to arrive at the analytical answer. Graphical analysis has been performed to show how nondimensional characteristics dominate the thermal gradient of the fin. The thickness and inner radius of a fin are crucial factors that impact the heat transmission rate. Based on the analysis, it can be concluded that a cost-effective annular rectangular fin can be achieved by maintaining a thickness of 0.1 cm and an inner radius of 0.2 cm. [ABSTRACT FROM AUTHOR]

The Seville Principles gather in their definitions the 3D representation of heritage assets in their context, that is, elements such as the surroundings and landscape, for both virtual reconstructions and virtual recreations. Currently, there are few virtual reconstructions that implement the historical-archaeological evidence scale to show the veracity of the work that has been carried out. Moreover, none of the existing propositions of historical-archaeological evidence scales consider the veracity of the represented terrain. Authors assign a neutral colour to the terrain, different from those applied to the evidence levels, in order to differentiate the former from the latter. The present study proposes the development of a methodology to implement a resolution scale that graphically represents, interprets and evaluates the setting of the terrain associated with virtual reconstructions. To this end, a literature review was conducted on the existing methodologies for the creation of Digital Terrain Models (DTM). The evaluation of the analysed information was key for the selection of the resolution levels, which was followed by the selection of the colours associated with each resolution level, taking into account the subjective connotations of colours. [ABSTRACT FROM AUTHOR]

Due to the numerous practices of non-Newtonian fluids in technological and industrial fields, the attention towards such fluids increases incredibly. The highly nonlinear equations emerge in the modeling of the non-Newtonian fluids. The differential transform method is one of the analytical methods which is used to acquire the solution to these complicated nonlinear equations in the series form. The current analysis comprises the squeeze flow of non-Newtonian fluid in two dimensions. Two infinite parallel plates are considered in which the time-dependent fluid is squeezed. The heat transfer mechanism is deliberated with the significance of heat absorption/generation. The nonlinear setup of ordinary differential equations is acquired by practicing the appropriate similarity variables on the governing equations of the concerned flow mechanism. The nonlinear setup is analytically resolved with the help of an analytical differential transform method. For the authenticity of the differential transform method, the analytical outcomes are compared with the numerical results. Graphical illustrations of fluid temperature and velocity profiles relative to the pertinent parameters are briefly explicated numerically and analytically. The fluid velocity demonstrates the descending behavior and the temperature field exhibits the expanding nature relative to the squeezing parameter. [ABSTRACT FROM AUTHOR]

The temperature distribution in a conductive-radiative rectangular profiled annular fin with internal heat generation is scrutinized in the present investigation. The nonlinear variation of thermal conductivity and heat transfer coefficient governed by the power law is considered. The analytical approximation for the non-dimensional temperature profile is obtained using the differential transform method (DTM)-Pade approximant. The nondimensionalization of the governing energy equation using dimensionless terms yields a nonlinear ordinary differential equation (ODE) with corresponding boundary conditions. The resulting ODE is analytically solved with the assistance of the DTM-Pade approximant procedure. Furthermore, the impact of thermal parameters on the temperature field and thermal stress is elaborated with graphs. The important results of the report divulge that temperature distribution greatly enhances with an augmentation of the heat generation parameter, but it gradually reduces with an increment in the magnitude of the thermogeometric and radiative-conductive parameter. [ABSTRACT FROM AUTHOR]

Digital bottom models are commonly used in many fields of human activity, such as navigation, harbor and offshore technologies, or environmental studies. In many cases, they are the basis for further analysis. They are prepared based on bathymetric measurements, which in many cases have the form of large datasets. Therefore, various interpolation methods are used for calculating these models. In this paper, we present the analysis in which we compared selected methods for bottom surface modeling with a particular focus on geostatistical methods. The aim was to compare five variants of Kriging and three deterministic methods. The research was performed with real data acquired with the use of an autonomous surface vehicle. The collected bathymetric data were reduced (from about 5 million points to about 500 points) and analyzed. A ranking approach was proposed to perform a complex and comprehensive analysis integrating typically used error statistics—mean absolute error, standard deviation and root mean square error. This approach allowed the inclusion of various views on methods of assessment while integrating various metrics and factors. The results show that geostatistical methods perform very well. The best results were achieved with the modifications of classical Kriging methods, which are disjunctive Kriging and empirical Bayesian Kriging. For these two methods, good statistics were calculated compared to other methods (for example, the mean absolute error for disjunctive Kriging was 0.23 m, while for universal Kriging and simple Kriging, it was 0.26 m and 0.25 m, respectively). However, it is worth mentioning that interpolation based on radial basis function in some cases is comparable to Kriging in its performance. The proposed ranking approach was proven to be useful and can be utilized in the future for choosing and comparing DBMs, mostly in mapping and analyzing seabed changes, for example in dredging operations. The research will be used during the implementation of the new multidimensional and multitemporal coastal zone monitoring system using autonomous, unmanned floating platforms. The prototype of this system is at the design stage and is expected to be implemented. [ABSTRACT FROM AUTHOR]

Purpose: A huge volume of published research articles is available on social media which evolves because of the rapid scientific advances and this paper aims to investigate the research structure of social media. Design/methodology/approach: This study employs an integrated topic modeling and text mining-based approach on 30381 Scopus index titles, abstracts, and keywords published between 2006 and 2021. It combines analytical analysis of top-cited reviews with topic modeling as means of semantic validation. The output sequences of the dynamic model are further analyzed using the statistical techniques that facilitate the extraction of topic clusters, communities, and potential inter-topic research directions. Findings: This paper brings into vision the research structure of social media in terms of topics, temporal topic evolutions, topic trends, emerging, fading, and consistent topics of this domain. It also traces various shifts in topic themes. The hot research topics are the application of the machine or deep learning towards social media in general, alcohol consumption in different regions and its impact, Social engagement and media platforms. Moreover, the consistent topics in both models include food management in disaster, health study of diverse age groups, and emerging topics include drug violence, analysis of social media news for misinformation, and problems of Internet addiction. Originality/value: This study extends the existing topic modeling-based studies that analyze the social media literature from a specific disciplinary viewpoint. It focuses on semantic validations of topic-modeling output and correlations among the topics and also provides a two-stage cluster analysis of the topics. [ABSTRACT FROM AUTHOR]

Earthquakes, extreme rainfall, or human activity can all cause landslides. Several landslides occur each year around the world, often resulting in casualties and economic consequences. Landslide susceptibility mapping is considered to be the main technique for predicting the likelihood of an event based on the characteristics of the physical environment. Digital Terrain Model (DTM) is one of the fundamental data of modeling and is used to derive important conditional factors for detailed scale landslide susceptibility analyses. With this in mind, this study aimed to compare landslide susceptibility maps generated by Random Forest (RF) machine learning algorithm with data from Light Detection and Range (LiDAR) and Unmanned Aerial Vehicle (UAV). To this end, the performance achieved in prediction was evaluated using statistical evaluation measures based on training and validation datasets. The obtained results showed that the accuracy of both models is greater than 0.70, the area under the curve (AUC) is greater than 0.80, and the model generated from the LiDAR data is more accurate. The results also showed that the data from UAV have potential to use in landslide susceptibility mapping on an intra-urban scale, contributing to studies in risk areas without available data. [ABSTRACT FROM AUTHOR]

The characterization is an elegant property of distributions that uniquely defines the associated stochastic model. The power function distribution is a flexible model which is often used for the analysis of income data, lifetime data, and modeling of failure procedures. Weighted distributions have wide applications in real-life problems, where the probabilities of events are observed and recorded by making modifications to probabilities of actual occurrence of events considering methods of ascertainment. In this paper, we considered the weighted power function (WPF) distribution and used some reliability measures to characterize it. We characterized the WPF distribution by various techniques like mean inactivity times, mean residual function, conditional moments, conditional variance, doubly truncated mean, incomplete moments and reverse hazard function. [ABSTRACT FROM AUTHOR]

In this article, the problem of the free vibration behavior of a cantilever Euler-Bernoulli beam with various non-classical boundary conditions, such as rotational, translational spring, and attached mass is investigated. For describing the differential equation of the system. An analytical procedure is proposed firstly, and a numerical method based on the differential transform method DTM is developed in order to validate the obtained results. A parametric study for various degenerate cases is presented with the aim to analyze the influence of rotational stiffness, vertical stiffness, and mass ratio on the free vibration response of the beam, particularly on its modal characteristics. The results show that the non-classical boundary conditions significantly affect the natural frequency and mode shapes of the studied beam system in comparison to the case of a classical boundary conditions such as Simply supported, clamped-clamped, etc. The comparison between the obtained results based on the proposed analytical solution and numerical scheme, and those available in the literature shows an excellent agreement. [ABSTRACT FROM AUTHOR]

The Digital Terrain Model (DTM) is an important dataset for various applications such as hydrology, environmental sciences, urban planning, etc. Majority of the satellite-based medium resolution (30 m - 90 m) Digital Surface Model (DSM) products are freely available and widely used around the world. The generation of a DTM from these products is a tedious process. In this paper, a simple algorithm is developed to classify the ground and nonground pixels in the DSM. The algorithm is tested on ALOS – World 3 D 30 m (AW3D30) DSM for small patches in the cities of Chennai, Mumbai and Cairo. Based on general assumption of the minimum elevation difference that exists between the ground and non-ground objects a slope threshold is used to initially classify the DSM. The elevations of the classified pixels are then used iteratively to assign counter values to the pixels. These counter values are finally used to classify the data and the ground pixels are interpolated using Inverse Distance Weighted (IDW) technique to generate the DTM. The proposed algorithm is quantitatively assessed and has a Type I error of 2.33%, Type II error of 1.67%, Total error of 2% and Kappa coefficient value of 96%. Additionally, R² and RMSE values of 0.9589 and ± 0.429 m were observed when compared against a reference DTM. [ABSTRACT FROM AUTHOR]

In this article, the authors study the comparison of the generalization differential transform method (DTM) and fuzzy variational iteration method (VIM) applied to determining the approximate analytic solutions of fuzzy fractional KdV, K(2,2) and mKdV equations. Furthermore, we establish the approximation solution two-and three-dimensional fuzzy time-fractional telegraphic equations via the fuzzy reduced differential transform method (RDTM). Finding an exact or closed-approximation solution to a differential equation is possible via fuzzy RDTM. Finally, we present the fuzzy fractional variational homotopy perturbation iteration method (VHPIM) with a modified Riemann-Liouville derivative to solve the fuzzy fractional diffusion equation (FDE). Using this approach achieves a rapidly convergent sequence that approaches the exact solution of the equation. The proposed methods are investigated based on fuzzy fractional derivatives with some illustrative examples. The results reveal that the schemes are highly effective for obtaining the solutions to fuzzy fractional partial differential equations. [ABSTRACT FROM AUTHOR]

The present level of literature on the subject matter indicates that nothing is known on the heat transfer across the couple stress rheological fluid flowing over a vertical avenue with Robin (mixed) wall conditions. The obtained conservation equations of the model are solved through DTM (differential transform method) and RPM (regular perturbation method). The nondimensional parameters obtained are a couple stress parameter, Brinkman number, mixed convection parameter, and Biot number. The computations reveal that flow acceleration and thermal enhancement is induced with increasing mixed convection parameter and Brinkman number for symmetric and asymmetric conditions. Increasing couple stress parameters dwindle the velocity and temperature for symmetric and asymmetric cases. The large values of the mixed convection parameter and Brinkman number increase the Nusselt values at the left wall and reduces at the right wall. The mass flow rate is augmented with the mixed convection parameter and Brinkman number but it is reduced with the couple stress parameter. The DTM, RKSM, and RPM solutions are in good agreement. [ABSTRACT FROM AUTHOR]

The first order derivatives of a Digital Elevation Model (DEM) defined over a regular grid are usually computed without an uncertainty estimate. The standard procedure involves a compact 3 × 3 window. Using a Taylor expansion, an uncertainty interval for each partial derivative as a function of the cell size was devised using two estimates, either of different resolution or of different order. The intervals for slope and aspect can be derived afterwards. We carried out an experiment comparing some different estimates of the slope and aspect over a synthetic surface representative of a real topography and amenable to offer an exact derivative. The partial derivatives were numerically estimated with four different procedures: the Simple procedure defined by Jones over a 2 × 2 window, the Evans–Young procedure using a centered difference over a 3 × 3 window, and using a 5 × 5 window both with an extrapolated Evans–Young procedure and the expression due to Florinsky. The results confirm that intervals for both slope and aspect always included the exact value even after drastically increasing the cell size. Finally, a real case with an integer-valued DEM was considered, illustrating the combined effect of Representation and Truncation error. [ABSTRACT FROM AUTHOR]

Balstrøm, T. and Kirby, J., 2022. A GIS-based screening workflow for coastal storm surge impact assessments and mitigation action consideration. Journal of Coastal Research, 38(4), 712–724. Coconut Creek (Florida), ISSN 0749-0208. A GIS-based screening workflow is presented, providing first overviews of storm surge–induced inundation impacts along coastlines and where to consider mitigative action. The modeling is based on analysis of a hydro-conditioned digital terrain model (DTM) in Esri's ArcGIS Pro environment targeting undergraduate students, professional municipality planners, federal agencies, and more. Unlike existing commercial inundation modeling software, this application works in a simplified timeless setting on steady-state surge levels. This is accomplished only at the cost of not predicting when a specific targeted location is inundated. In return, fast computations are obtained. First, it is demonstrated how the DTM is turned into a hydro-conditioned terrain model, DHyMSea, protecting surges from entering land where sluices, high-water flaps, etc., are present. Second, the inundation screening is initiated for a user-defined number of sea levels. The outputs are individual raster layers for each level showing inundation extents and depths. Also, outputs are produced for each modeled level to back trace where the inundation came from. Third, a combined raster shows the minimum surge level to inundate any cell in the DHyMSea. Fourth, when considered where to raise protecting dikes, they can be digitized and have their elevation values stamped onto the DHyMSea. Finally, the inundation scenarios can be re-executed to evaluate the mitigation impact; if necessary, the dikes' locations and elevation properties can be reconsidered, and the workflow re-executed once more. The workflow has proven successful in first assessments of inundation threats where sea levels are expected to rise significantly over the coming decades. Additionally, the workflow has proven successful in quality assessments of a DTM. To demonstrate the workflow's capabilities, storm surge consequences for the greater Copenhagen region's coastline in Denmark are discussed for inundation scenarios ranging from 1.0 m to 3.9 m above sea level in steps of 0.1 m. [ABSTRACT FROM AUTHOR]

In this article, the special properties of the magnetic field and nanoparticles on the Jeffery–Hamel flow are considered via an influential numerical differential transform method (DTM). The proposed technique is very helpful and appropriate for solving highly nonlinear differential equations. Furthermore, the outcomes are compared with those of other techniques such as HPM, HAM, ADM, and a numerical method (Rung–Kutta method) in the literature revealing that the current method solution is better than other methods. Also, the properties of Reynolds number, Hartmann number, and angle of the channel on applications of the MHD Jeffery–Hamel flow are discussed. [ABSTRACT FROM AUTHOR]

How to enlarge the output displacement is a key issue in the research field of microgrippers. It is difficult to further enlarge the output displacement for the traditional displacement transmission mechanism (DTM). In this research, a two-stage amplification cylinder-driven DTM based on the compliant mechanisms is designed to realize the displacement output expansion. The opening and closing of the clamping jaws is driven by the air cylinder to enlarge the output displacement of the microgripper. According to the analysis of statics model of the mechanism, the relationship between the output displacement of the microgripper and the driving pressure of the cylinder is established. The magnification of the microgripper is obtained using a dynamic model. Moreover, based on the finite element analysis, the mechanical structure parameters are optimized. The microgripper was fabricated by utilizing wire electro discharge machining (WEDM) technique, and then a series of experiments were carried out to obtain the relationship between the displacement and the driving pressure. It is found that the maximum output displacement measured is 1190.4 µm under the pressure of 0-0.6 MPa, corresponding to the magnification of 47.63. Compared with the results of finite element analysis and theoretical calculation, the test results have a discrepancy of 2.39% and 6.62%, respectively. The microgripper has successfully grasped a variety of micro-parts with irregular shapes, and parallel grasping can be achieved, demonstrating the potential application of this design in the field of micromanipulation. [ABSTRACT FROM AUTHOR]

The geospatial data accuracy and specification requirements for LTE and 5G radio propagation and optimization are much higher than those used in planning 2G and 3G networks. The recommended geospatial data resolution of 1-2 meters allows the display of the smallest parts of geospatial objects. In the article, we describe the technology and its practical implementation to produce an accurate clutter height (raster canopy height model) for the purposes of LTE and 5G radio network propagation and optimization. This technology, which is based on aerial images, may be adapted to use LiDAR data. The technology includes the data integration between the different software. The processing of digital terrain models, obstacles (buildings and vegetation) and DSM cloud points is performed in geographic information systems, such as ArcGIS. The technology was proven by the practical implementation and calculation in multi-technology wireless network design and optimization platform Atoll. [ABSTRACT FROM AUTHOR]

Determining the optimal path between two points in a 3D point cloud is a problem that have been addressed in many different situations: from road planning and escape routes determination, to network routing and facility layout. This problem is addressed using different input information, being 3D point clouds one of the most valuables. Its main utility is to save costs, whatever the field of application is. In this paper, we present a fast algorithm to determine the least cost path in an Airborne Laser Scanning point cloud. In some situations, like finding escape routes for instance, computing the solution in a very short time is crucial, and there are not many works developed in this theme. State of the art methods are mainly based on a digital terrain model (DTM) for calculating these routes, and these methods do not reflect well the topography along the edges of the graph. Also, the use of a DTM leads to a significant loss of both information and precision when calculating the characteristics of possible routes between two points. In this paper, a new method that does not require the use of a DTM and is suitable for airborne point clouds, whether they are classified or not, is proposed. The problem is modeled by defining a graph using the information given by a segmentation and a Voronoi Tessellation of the point cloud. The performance tests show that the algorithm is able to compute the optimal path between two points by processing up to 678,820 points per second in a point cloud of 40,000,000 points and 16 km 2 of extension. [ABSTRACT FROM AUTHOR]

In this research work, a four-dimensional tumor-immune response model is considered. The considered tumor model is a system of four differential equations consisting of four different cell populations (variables): the tumor cells (TCs), effector cells (ECs), helper tumor cells (HTCs), and Tregs. The interaction among these cell populations is represented by the system of ordinary differential equations (ODEs). The solution of the system is obtained by using the differential transformation method (DTM). DTM is a straightforward method and gives the series solution of the system. Numerical simulation and graphical analysis are also done by choosing four different initial conditions of the system. The solution series of a system for four different cases are obtained and finally compared with each other. The analysis shows that the model behavior is Chaotically dependent on initial conditions. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) allow relatively cheap and fast acquisition of high-resolution data for small areas, making it possible to produce not only an orthophoto, understood as a two-dimensional product, but also a three-dimensional point cloud, which is the basis for obtaining a digital terrain model (DTM). The use of high-resolution image and elevation data may allow accurate shoreline delineation in areas where such measurement is not possible with other methods and further use of these data, e.g. for the production of electronic navigation charts. The accuracy of the final product, the DTM, is significantly affected by the photogrammetric classification process of the point cloud and the correct separation of the ground class. The aim of this study was to assess the effectiveness of the algorithms used to classify ground in photogrammetric point clouds and obtain correct DTMs. Three algorithms were tested: Adaptive Triangulated Irregular Network, Progressive Triangulated Irregular Network, and Multiscale Curvature Classification. The study involved two test areas covering natural shorelines. Images acquired with a UAV on the X8 system and a Sony alpha camera with a mounted 15 mm wide-angle lens were used as data for the research experiment. Accuracy analysis of the developed models was performed using check points acquired by the GNSS-RTK method. [ABSTRACT FROM AUTHOR]

We conducted sentiment classification for news reports during the COVID-19 pandemic on Sino-Japanese relations from Chinese and Japanese media. Based on the Word2vec and Dynamic Topic Models, we analyzed the macroscopic dimension of theme distribution and the semantic change process of "Sino-Japanese" related words. The results indicate that Chinese media reports are mainly neutral, but Japanese ones are mainly negative. The meaning of the terms related to "Sino-Japanese" has not changed significantly, but there are minor differences in the content of reports on the same subject in different periods. During Suga's administration, the overall stability of Sino-Japanese relations and the continued advancement of pragmatic cooperation are expected to continue. [ABSTRACT FROM AUTHOR]

In this study, two methods have been proposed to find the critical buckling load of bars that are in water and buckled under the effect of P singular force and distributed self-weight. Three different Euler's cases were taken into account in the study. In the first method, the solution of the stability differential equation of the bar in water is solved by the Differential Transformation Method (DTM), while in the second method, the Dunkerley formula is applied to determine the critical buckling load factor of the buckled bar in water. Finally, the results obtained by solving an example with the two proposed methods were compared with the finite element method. SAP 2000 program was used for finite element analysis. From the results obtained, it was observed that the two methods gave results in good agreement to the finite element method. [ABSTRACT FROM AUTHOR]

This paper introduces a theoretical and numerical study for the problem of Casson fluid flow and heat transfer over an exponentially variable stretching sheet. Our contribution in this work can be observed in the presence of thermal radiation and the assumption of dependence of the fluid thermal conductivity on the heat. This physical problem is governed by a system of ordinary differential equations (ODEs), which is solved numerically by using the differential transformation method (DTM). This numerical method enables us to plot figures of the velocity and temperature distribution through the boundary layer region for different physical parameters. Apart from numerical solutions with the DTM, solutions to our proposed problem are also connected with studying the skin-friction coefficient. Estimates for the local Nusselt number are studied as well. The comparison of our numerical method with previously published results on similar special cases shows excellent agreement. [ABSTRACT FROM AUTHOR]

This paper presents an extension of multipoint machining technique, called the Drop Spin and Tilt (DST) method, that spins the tool on two axes, allowing for the generation of multiple contact points at varying distances around the first point of contact. The multiple DST second points of contact were used to manually generate a toolpath with uniform spacing between the two points of contact. The original DST method used a symbolic algebra package to position the tool on a bi-quadratic surface; our extension is a numerical solution that allows positioning a toroidal tool on a tensor product Bézier surface, which we tested on bi-degrees 2, 3, 4, and 5. On the three bicubic surfaces we tested, the average number of initial seeds for our numerical method was less than 5 across all three surfaces, and the average number of Newton iterations was less than 20 except when the curvature of the tool closely matches the local surface curvature (in which case more iterations were required). Furthermore, we investigate the spread of possible second points of contact as the tool is spun around these two axes, demonstrating the feasibility of using the method to control the machining strip width. [ABSTRACT FROM AUTHOR]

Cross-track interferometry (CTI) for synthetic aperture radars (SARs) is a useful technique that has been widely used to retrieve a digital surface model (DSM). One aim of CTI observations is to measure the heights of objects in a target scene, and a straightforward approach for this purpose is to subtract an external reference of the digital terrain model (DTM) from the CTI DSM. On the other hand, the refinement of parameters for CTI, namely interferometric SAR (InSAR) parameters, using an external reference is often required before subtraction. To avoid undesired degradation caused by potential differences in the terrain height between the references used for subtraction and refinement, it is preferable to use a single DTM as a common reference. However, InSAR parameters cannot be refined correctly if a DTM is used as an external source for GCPs without careful considerations since a CTI DSM contains objects unlike a DTM. In this context, we propose a novel method that refines InSAR parameters based on a DTM. The features of the proposed method are that automatically extracted footprints of vertical structures are selected as ground control point (GCP) candidates and that GCPs expected to lie at the terrain level are iteratively selected by fitting the histogram of the height difference with one or two normal distributions. This enables us to refine InSAR parameters with a single CTI DSM dataset and an external DTM without any interactive operations in the process. An experiment based on a real CTI dataset for a complex scene and a laser DTM demonstrates the promising performance of the proposed method. The median and interquartile range of the height error in terrain areas for the test scene are −0.18 m and 1.81 m, respectively, which are acceptable for various applications. The degrees of improvement resulting from the use of two novel ideas in the test scene are found to be comparable. The proposed method is predicted to be effective for developed areas such as urban and residential areas owing to its inherent limitations. [ABSTRACT FROM AUTHOR]

Digital Soil Mapping (DSM) is a subdiscipline of pedology, where soil cover is modelled through use of spatial - temporal relations between environmental covariates and soil. The process of quantitative terrain description used in DSM is called terrain parametrization, where terrain attributes (morphometric factors, Digital Terrain Model derivatives) are the most used predicators. Terrain parameterisation was used as a tool in the hydrological survey workshop long before computers had been in use. With the development of digitisation, it also began to be used to determine selected soil attributes, which was greatly facilitated by GIS applications. A significant breakthrough in the importance of terrain attributes in the creation of soil maps and models took place with the formalisation of rules for digital soil mapping. Literature describes over 50 indices, although only a few of them are commonly applied. This applies to single soil attributes as well as more advanced implementations in more sophisticated models such as artificial intelligence algorithms. The aim of the following article is to present the main components of DSM and to describe characteristics of the most commonly derivatives of DTM applied there, also refers to several examples of the use of terrain parameters in the context of DSM in terms of the resolution of the elevation model used. [ABSTRACT FROM AUTHOR]

Today, many photogrammetric mapping methods have used drones to retrieve and record data about objects on earth. This is due to the fact that the use of a drone equipped with GNSS (Global Navigation Satellite System) for measurements is very efficient and cheaper compared to renting an aircraft, it also allows flying over hard to reach areas and significantly reduces the time. The development of UAV technology in Romania is still in its infancy, and the legislative framework imposes certain restrictions even for small drones. Thus, in order to use the aircraft, the approval of the Romanian Civil Aeronautical Authority is required, as well as an approval from the Ministry of National Defense. In this way, flights are regulated in terms of distance, altitude and area. The purpose of the research was the realization and technical detailing of a workflow for the generation of orthophotoplans and threedimensional models, by photogrammetric techniques (UAS/UAV), which can be used in various topocadastral works or as primary geospatial data in overlay analysis, in various other fields: urbanism, agriculture, spatial planning, geomorphology, etc. This paper presents the results of the application of UAV photogrammetry data in the mapping of Labaşinţ locality from Arad County, using a WingtraOne VTOL tailsiter drone, equipped with a Sony RX1RII camera with a 42.4 megapixel CMOS sensor, 35 mm, fullframe and a GNSS system. high precision. The final stage of data processing includes the generation of orthophotoplanes, mosaics, raster images, TIN and DEM formats as well as the generation of point clouds. The use of drones in the field of geospatial science is currently in high demand due to its relatively easy operation and relatively affordable cost compared to satellite systems, especially high resolution images. One of the benefits of using drones is that they take aerial photographs that are then processed for mapping so that they can be used to support the acquisition of spatial data. [ABSTRACT FROM AUTHOR]

In this manuscript, we consider the first order neutral Volterra integro-differential equation (NVIDE) with delay argument. Firstly, we obtain novel sufficient conditions to establish the asymptotic behaviours of solutions of considered NVIDE using the Lyapunov method and present an example to demonstrate the applicability of proposed method. Secondly, we get some numerical solutions for a particular case of considered NVIDE via the differential transformation method (DTM). The results of this manuscript are novel and they improve some existing ones in the literature. [ABSTRACT FROM AUTHOR]

Temporomandibular Disorder (TMD) is a disorder that affects the temporomandibular joints and masticatory muscles, among other facial structures. Symptoms can generate pain in these joints and muscles, as well as pain in the head, ear, noise in the joints, tinnitus, ear pain, limitation in opening the mouth, among others. Its etiology has multifactorial causes. Among the factors that can influence TMD are psychological. Objective: This study aimed to identify cognitive behavioral therapy (CBT) strategies used to treat individuals diagnosed with TMD. Method: Literature review. The databases used were PePSIC, SCIELO, PubMed and BVS, in English and Portuguese. The descriptors used in databases were: TMD and cognitive-behavioral therapy; Temporomandibular disorders and cognitive behavioral therapy, Temporomandibular disorders and cognitive therapy, TMD and cognitive behavioral therapy; Temporomandibular disorder and cognitive behavioral therapy, Temporomandibular disorder and cognitive therapy. The filters used to include the studies were: articles on CBT interventions, articles in Portuguese and/or English and with publication dates in the last three years. Results: Six articles were analyzed, after passing the filters. Discussion: The results show that the main CBT guidelines used in the treatment of TMD are: cognitive restructuring, self-management, psychoeducation and relaxation training. They also suggest that a CBT can bring positive contributions to TMD cases, but the sample in this study was small. The articles point out that multidisciplinary treatment must include cognitive and behavioral interventions. Thus, the need for further research to verify the effects of CBT in patients with TMD is evidenced, especially, studies with clinical trials. [ABSTRACT FROM AUTHOR]

The relationship between precipitation and elevation is a well-known topic in the field of geography and meteorology. Radar-based precipitation data are often used in hydrologic models, however, they have several inaccuracies, and elevation can be one of the additional parameters that may help to improve them. Thus, our aim in this article is to find a quantitative relationship between precipitation and elevation in order to correct precipitation data input into hydrologic models. It is generally accepted that precipitation increases with elevation, however, the real situation is much more complicated, and besides elevation, the precipitation is dependent on several other topographic factors (e.g., slope, aspect) and many other climatic parameters, and it is not easy to establish statistically reliable correlations between precipitation and elevation. In this paper, we examine precipitation-elevation correlations by using multiple regression analysis based on monthly climatic data. Further on, we present a method, in which these regression equations are combined with kriging or inverse distance weighting (IDW) interpolation to calculate precipitation fields, which take into account topographic elevations based on digital terrain models. Thereafter, the results of the different interpolation methods are statistically compared. Our study areas are in the hilly or low mountainous regions of Hungary (Bakony, Mecsek, Börzsöny, Cserhát, Mátra and Bükk montains) with a total of 52 meteorological stations. Our analysis proved that there is a linear relationship between the monthly sum of precipitation and elevation. For the North Hungarian Mountains, the correlation coefficients were statistically significant for the whole study period with values between 0.3 and 0.5. Multivariate regression analysis pointed out that there are remarkable differences among seasons and even months. The best correlation coefficients are typical of late spring-early summer and October, while the weakest linear relationships are valid for the winter period and August. The vertical gradient of precipitation is between one and four millimetres per 100 metres for each month. The statistical comparison of the precipitation interpolation had the following results: for most months, co-kriging was the best method, and the combined method using topography-derived regression parameters lead to only slightly better results than the standard kriging or IDW. [ABSTRACT FROM AUTHOR]

River valleys have been observed on Titan at all latitudes by the Cassini‐Huygens mission. Just like water on Earth, liquid methane carves into the substrate to form a complex network of rivers, particularly stunning in the images acquired near the equator by the Huygens probe. To better understand the processes at work that form these landscapes, one needs an accurate digital terrain model (DTM) of this region. The first and to date the only existing DTM of the Huygens landing site was produced by the U.S. Geological Survey (USGS) from high‐resolution images acquired by the DISR (Descent Imager/Spectral Radiometer) cameras on board the Huygens probe and using the SOCET SET photogrammetric software. However, this DTM displays inconsistencies, primarily due to nonoptimal viewing geometries and to the poor quality of the original data, unsuitable for photogrammetric reconstruction. We investigate a new approach, benefiting from a recent reprocessing of the DISR images correcting both the radiometric and geometric distortions. For the DTM reconstruction, we use MicMac, a photogrammetry software based on automatic open‐source shape‐from‐motion algorithms. To overcome challenges such as data quality and image complexity (unusual geometric configuration), we developed a specific pipeline that we detailed and documented in this article. In particular, we take advantage of geomorphic considerations to assess ambiguity on the internal calibration and the global orientation of the stereo model. Besides the novelty in this approach, the resulting DTM obtained offers the best spatial sampling of Titan's surface available and a significant improvement over the previous results. Key Points: We create a new digital terrain model (DTM) of the Huygens landing site that offers the best available resolution of river valleys on TitanThe complexity of the data set requires a tailor‐made reconstruction procedure that is detailedThe workflow uses reprocessed Huygens/DISR images and an automated shape‐from‐motion algorithm to improve an earlier DTM [ABSTRACT FROM AUTHOR]

A high-resolution dataset, such as an unmanned aerial vehicle (UAV) data provides new insight of information extraction for remote sensing applications. Object-based image analysis (OBIA) is emerging as an effective tool in the field of aerial image processing and remote sensing applications. The study primarily demonstrates how UAV data can be utilized for the extraction of urban land spatial information and aims explicitly at the extraction of vacant urban parcels within city premises. The study is initiated with object-based urban feature extraction using Multiresolution segmentation (MRS). Further, classification is performed by defining a set of rules to extract vacant urban parcel spatial information. Digital elevation and normalized surface models (DEM and n-DSM) are utilized for refining the segmentation results. The attribution and reclassification of objects are performed based on DEM and n-DSM values. Moreover, the challenges for removing the obligations in delineating the vacant parcel boundaries are addressed by utilizing the excess vegetation index (EVI). The applicability of the approach is examined by three accuracy indexes, which are completeness, correctness, and quality. Overall high accuracy is obtained for extracted urban land parcels in terms of accuracy indexes. The proposed algorithm can be effectively utilized for numerous applications such as building floor extraction, gathering information for vacant urban parcels within city premises, delineation of building footprints, damaged building estimations, and many more. [ABSTRACT FROM AUTHOR]

Most ground filtering algorithms are primarily designed for airborne LiDAR point cloud processing and their successful use in identifying ground points from photogrammetric point clouds remains questionable. We compared six ground filtering algorithms implemented in Metashape, ArcGIS, CloudCompare, LAStools, and PDAL. We used UAV photogrammetry-based (acquired under leaf-off conditions) and airborne LiDAR (leaf-on) point clouds of the same area to: (i) compare accuracy of generated DTMs; (ii) evaluate the effect of vegetation density and terrain slope on filtering accuracy; and (iii) assess which algorithm parameters have the greatest effect on the filtering accuracy. Our results show that the performance of filtering algorithms was affected by the point cloud type, terrain slope and vegetation cover. The results were generally better for LiDAR (RMSE 0.13–0.19 m) than for photogrammetric (RMSE 0.19–0.23 m) point clouds. The behavior in varying vegetation and terrain conditions was consistent for LiDAR point clouds. However, when applied on photogrammetric point clouds, the algorithms' behavior was inconsistent, especially in areas of steep slope (except for the Progressive Triangulated Irregular Network in LAStools). Parameters related to the selection of the initial minimum elevation ground points were the most influential in all algorithms and point clouds. [ABSTRACT FROM AUTHOR]

The purpose of this article is to accomplish a Digital Terrain Model, Digital Surface Model and an orthophotoplan - orthomosaic of an area within the Didactic and Experimental Resort of BUASVM Timisoara based on geomatic technologies. The interest for UAVs has been constantly growing, researchers and developers use a lot of resources and efforts to contribute to this topic, especially in applications of geomatics in various fields such as: agricultural and forestry, autonomous surveillance (Herbei and Sala, 2020), emergency and disaster management, traffic management and 3D mapping with photogrammetry. This increase is mainly due to the fact that UAV systems are a reliable and low-cost alternative, fast speed, high maneuverability and high security for image collection. A DJI Phantom 4 drone was used in this work. Phantom IV is a system composed of a drone (UAV) and a mobile RTK station and is suitable for aerial photography and aerial filming activities suitable for data processing in order to obtain orthophotoplanes, point clouds or 3D modeling. Most drones have built-in GPS, IMU (inertial measurement unit) and barometric altimeter, to help navigation. The default positional accuracy is generally good enough for many GIS applications. For example, the DJI Phantom 3 Pro has a position accuracy of ± 1m. If necessary, you can improve position accuracy using ground control points (GCPs), see Ground control points. Ground control points (GCPs) are used in image processing to improve the positional accuracy of data. GCPs are physical locations marked with a fixed position, the coordinates of which have been accurately determined (for example, using a combination of navigation systems, such as GPS and GLONASS, or by using differential GPS). In order to purchase images from the field with UAV technology, the Pix4D application and a mobile tool with Android OS were used, which allowed the realization of the flight plan to acquire the images from the desired location. [ABSTRACT FROM AUTHOR]

Methods of estimating the total amount of above-ground biomass (AGB) in crop fields are generally based on labourious, random, and destructive in situ sampling. This study proposes a methodology for estimating herbaceous crop biomass using conventional optical cameras and structure from motion (SfM) photogrammetry. The proposed method is based on the determination of volumes according to the difference between a digital terrain model (DTM) and digital surface model (DSM) of vegetative cover. A density factor was calibrated based on a subset of destructive random samples to relate the volume and biomass and efficiently quantify the total AGB. In all cases, RMSE Z values less than 0.23 m were obtained for the DTM-DSM coupling. Biomass field data confirmed the goodness of fit of the yield-biomass estimation (R2=0.88 and 1.12 kg/ha) mainly in plots with uniform vegetation coverage. Furthermore, the method was demonstrated to be scalable to multiple platform types and sensors. [ABSTRACT FROM AUTHOR]

The aim of this paper is to show that natural watercourses surveying gives the best results using integrated measurement methods (classical surveying and LiDAR). The paper contains comparison of the riverbed DTM results obtained using LiDAR data in relation to data derived from direct measurements. The paper involved the performance of appropriate tests on selected structures using integrated measurement techniques – GNSS, tachymetry and LiDAR. The conducted studies showed some limitations method for acquiring data from LiDAR. This is because the method does not enable the determination of measuring points coordinates which describe the topography in places inaccessible for a laser beam. [ABSTRACT FROM AUTHOR]

This paper analyses the research carried out in the Tiwanaku World Heritage site in Bolivia, using unmanned aerial vehicles and satellite images. The combined use of images with different scales has made it possible to locate many archaeological structures unknown to date (drainage systems, walls, circular crop marks, and a possible dock). The Sentinel‐2 images, which were processed using principal components analysis and histogram equalization, show the river beds, flood‐prone areas, and several buried drainage channels surrounding the most important structures. The archaeological evidence obtained with the digital terrain model and natural color/multispectral images enables us to contrast a new dimension of land and water uses that go beyond what was known to date. In the same way, these images enable us to understand in detail the environmental characteristics, land use, building distribution, and flood defense structures of the Tiwanaku culture throughout its history, within the context of the environmental conditions of the Bolivian altiplano. This study allowed the authors to collect new information and pose questions on the relationship of this site with water, as well as a better understanding of the extent and habitat of this historical population. [ABSTRACT FROM AUTHOR]

The problem of thin liquid film flow over a heated horizontal stretching surface permitted by uniform transverse magnetic field in the presence of variable heat flux is studied numerically. The ordinary differential equations describing the physical problem are solved approximately by the differential transformation method (DTM). A study of the convergence analysis of the proposed method is given. The effects of the various parameters governing the thin film flow and heat transfer in this study are discussed and presented graphically. Our paper contributes to the existing literature by introducing the numerical treatment using the DTM for the nonlinear system of ordinary differential equations, which describe a thin film fluid flow affected by the variable heat flux. [ABSTRACT FROM AUTHOR]

This article highlights a parametric investigation of the thermal analysis of variable thickness flat plate solar collector. Triangular profile of an absorber plate has been adopted from the point of view of saving in material. An approximate analytical model based on the Taylor series of expansion has been implemented for finding out the temperature distribution in the heat conduction direction of the absorber plate. Differential transform method (DTM) has been used to establish a new analytical formulation. The Modified Bessel's function has been applied for the comparison of the results produced by DTM. The variation of several temperature dependent parameters is studied for knowing the dependency effect. The efficiency of absorber plate has been analysed as a function of Biot number and the impact of aspect ratio on the plate performance has been highlighted. The present analytical approach has ability to determine the thermal performance of an absorber plate under an actual design condition with a minor modification of the analysis. The formulation of the present work is also suitable for the analysis of any shape of an absorber plate in flat-plate solar collectors. [ABSTRACT FROM AUTHOR]

Climate change and human activities have resulted in the receding of glaciers throughout the world including Pakistan. Glacier lake outburst floods (GLOFs) are amongst the most common climate‐change‐induced hazards in northern Pakistan. In the present study, GLOF mapping and modelling was carried out using remote sensing and geographical information system techniques coupled with ground‐truthing. Change detection techniques such as the normalized difference water index were applied on Landsat imagery for the identification of the temporal behaviour of Darkut glacial lake for the last 25 years. The depth of the lake was estimated to be 81 m and the volume of the lake was calculated using a digital terrain model and extracted as 9.79 × 106 m3. The glacial lake extent has increased from 0.045 to 0.154 km2 in the last two decades. Two GLOF scenarios (peak and extreme flood) were developed on an existing volume of water in the study. There are 14 households exposed to medium flood and 10 to low flood risk while one helipad and one school are also in the low flood zone in the first scenario (i.e. peak flood) based on 87.84 m3·s−1 of water. The second scenario (i.e. extreme flood) was executed on 3,128 m3·s−1 of water, in which 14 households are at high flood risk, eight at medium and 35 in a low flood zone, as well as one school, a helipad and a community stockpile which are exposed to low flood. The outcomes of the study will help in the development of risk management plans, preparedness strategies and risk reduction from GLOF hazard. [ABSTRACT FROM AUTHOR]