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This study explores foreign entrepreneurs' motivations and obstacles in China's business landscape. The research question is: What prominent factors drive foreign entrepreneurs to seek business opportunities in China, and what challenges do they encounter? A mixed-methods approach was employed, including a questionnaire survey of 240 foreign entrepreneurs in China, cross-tabulation analysis, chi-square tests, and thematic analysis. The findings reveal that financial gain, market opportunities, access to resources or networks, personal aspirations, and cultural factors motivate foreign entrepreneurs to venture into China. Language and communication barriers, cultural differences, administrative procedures, market competitiveness, logistics, remittances and international transfer issues, financial instability, discrimination, and racism pose significant challenges. The study highlights substantial similarities and dissimilarities in motivations and challenges based on gender and ethnicity. The study's novelty lies in its comprehensive exploration of the dynamics of foreign entrepreneurship in China, incorporating gender and ethnicity considerations and shedding light on logistics and shipping issues as obstacles. The study's practical implications could help policymakers and aspiring entrepreneurs formulate strategies to improve China's business landscape for foreign entrepreneurs. [ABSTRACT FROM AUTHOR]

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this short note, we present a probabilistic perspective on Schiffer's problem in inverse scattering theory, which asks whether one can uniquely determine the shape of an unknown obstacle by a single far-field measurement. It is a longstanding problem and has received considerable studies in the literature. We show that this conjecture holds true in more general settings in the probabilistic sense. Our new perspective has important implications from the practical viewpoint and also points an interesting direction of research for broader inverse problems. [ABSTRACT FROM AUTHOR]

In order to evaluate the soil quality status of farmland in Shawan City of Xinjiang, China and to clarify the key influencing factors on productivity level, and promote the construction of high standard farmland in Sha-wan City, this paper build the minimum dataset of farmland soil quality with principal component analysis and cluster analysis, and combined with an obstacle factor diagnostic model, the characteristics and obstacle factors of agricultural soil quality in the Shawan area were revealed. The results led to three main conclusions. (1) There were significant differences between the results of soil quality evaluations using different datasets. The soil quality indices determined using the minimum dataset based on cluster analysis and using the total dataset significantly positively correlated (R²=0.591, P<0.1),the Nash effective coefficient was -4.923, indicating that the minimum dataset based on cluster analysis gave better results than the minimum dataset based on principal component analysis. This indicated that the minimum dataset based on cluster analysis was more suitable than the minimum dataset based on principal component analysis for replacing the total dataset when evaluating farmland soil quality. (2) The overall soil quality in the study area was found to be moderate and better, and the soil quality indices were 0.130-0.641. Farmland in Shawan City was divided into five classes using the soil quality index minimum dataset. Class I soil was mainly in the northern and northwestern parts, and class V soil was mainly in the southeastern part of the study area, indicating that the soil quality was generally high in the northwest and low in the southeast. (3) There were obvious obstacles in the research area, which low organic matter contents, insufficient nitrogen, and high electrical conductivities were the main obstacles. The research results can be used to effectively improve the soil quality of local farmland. It is recommended that in the process of farmland management, not only applying organic fertilizer, take measures such as deep tillage, planting weeds, covering straw, and plastic film to improve the soil. [ABSTRACT FROM AUTHOR]

Copyright of Erzincan University Journal of Education Faculty / Erzincan Üniversitesi Egitim Fakültesi Dergisi is the property of Erzincan University Faculty of Education Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction. The article presents the axiological aspect of will as a phenomenon of a person's regulation of his behavior and scientific activity, in particular. The study of the mechanisms of volitional decisions in scientific knowledge is necessary, first of all, because the will is responsible for the formation of goals and the implementation of eff orts to realize them. The purpose of philosophical research is to identify the ontological sources of the phenomenon of will and their axiological analysis in scientific activity leading to creative judgments. Theoretical analysis. The axiological approach allows us to explore the possibilities of the mind, as opposed to impulsive desires, in conditions of making volitional decisions both in science and other forms of knowledge. The ontological basis of will is the presence of an obstacle, overcoming which becomes the fulfillment of a goal. In scientific activity, the will prevents the manifestation of emotional excitement, acting as a determinant of scientific research activity. An axiological analysis of will as a value and a source of positive emotions demonstrates the achievement of a goal by satisfying the need to overcome an obstacle that has a correlation with the category of singularity. Conclusion. A value analysis of the phenomenon of will shows the possibilities of human thinking for the most productive scientific activity, expressed in a combination of the optimal level of emotional stress and strong will.

The present contribution focuses on the thermal non-equilibrium handling of an unsteady mixed convection nanofluid flow within two-sided wavy and two-sided lid-driven porous enclosures due to the impact of the thermal radiation and inclined magnetic field. The forced convection situation is due to the movements of the left irregular and top regular boundaries. This pattern accounts for such impacts as the inter-phase heat transfer factor impact, the modified conductivity ratio and the thermal radiation aspects. The cavity includes apart heated wall of length b subjected to external Cu water (with particle diameter less than 100 nm) nanofluid. The governing equations have been solved utilizing Galerkin finite element (GFE) approach with CBS algorithm. Numerical outcomes for the flow and heat transfer for the fluid and solid phases are determined for miscellaneous combinations of the physical factors. Graphical and tabular outcomes pointing out interesting features of the physics of the problem are presented and discussed. The forced convection mode is dominance at higher values of $ \lambda $ λ and low values of Hartmann number Ha. Furthermore, the considered range of the nanoparameter ( $ 0 \le \varphi \le 0.1 $ 0 ≤ φ ≤ 0.1) gives an augmentation in the rate of the heat transfer up to 14.54%. [ABSTRACT FROM AUTHOR]

We studied an obstacle problem of a $ p $-Laplacian type in a bounded non-smooth domain whose nonlinearity is associated with a matrix weight. We established a global Calderón-Zygmund theory by proving that the gradient of a bounded weak solution is as integrable as both the gradient of the obstacle and the nonhomogeneous term in the weighted Lebesgue space with the desired estimate under possibly minimal regularity requirements of the given operator, which are a small log-BMO of the matrix weight, a weak small BMO in $ x $ variable and local uniform continuity in the solution $ u $ variable of the nonlinearity $ {\bf a}(x, u, Du) $, and a $ \delta $-Reifenberg flatness of the boundary. Our regularity theory on the obstacle problem covered a larger class of elliptic partial differential equations in the literature by allowing degenerate/singular nonlinearities, also depending on the solution $ u $. [ABSTRACT FROM AUTHOR]

Abstract Chemical bioreactions play a significant role in many of the microfluidic devices, and their applications in biomedical science have seen substantial growth. Given that effective mixing is vital for initiating biochemical reactions in many applications, micromixers have become increasingly prevalent for high-throughput assays. In this research, a numerical study using the finite element method was conducted to examine the fluid flow and mass transfer characteristics in novel micromixers featuring an array of pillars. The study utilized two-dimensional geometries. The impact of pillar configuration on mixing performance was evaluated using concentration distribution and mixing index as key metrics. The study explores the effects of pillar array design on mixing performance and pressure drop, drawing from principles such as contraction–expansion and split-recombine. Two configurations of pillar arrays, slanted and arrowhead, are introduced, each undergoing investigation regarding parameters such as pillar diameter, gap size between pillar groups, distance between pillars, and vertical shift in pillar groups. Subsequently, optimal micromixers are identified, exhibiting mixing efficiency exceeding 99.7% at moderate Reynolds number (Re = 1), a level typically challenging for micromixers to attain high mixing efficiency. Notably, the pressure drop remains low at 1102 Pa. Furthermore, the variations in mixing index over time and across different positions along the channel are examined. Both configurations demonstrate short mixing lengths and times. At a distance of 4300 μm from the inlet, the slanted and arrowhead configurations yielded mixing indices of 97.2% and 98.9%, respectively. The micromixers could provide a mixing index of 99.5% at the channel’s end within 8 s. Additionally, both configurations exceeded 90% mixing indices by the 3 s. The combination of rapid mixing, low pressure drop, and short mixing length positions the novel micromixers as highly promising for microfluidic applications.

A class of variational inequalities describing the equilibrium of elastic Timoshenko plates whose boundary is in contact with the side surface of an inclined obstacle is considered. At the plate boundary, mixed conditions of Dirichlet type and a non-penetration condition of inequality type are imposed on displacements in the mid-plane. The novelty consists of modelling oblique interaction with the inclined obstacle which takes into account shear deformation and rotation of transverse cross-sections in the plate. For proposed problems of equilibrium of the plate contacting the inclined obstacle, the unique solvability of the corresponding variational inequality is proved. Under the assumption that the variational solution is smooth enough, optimality conditions are obtained in the form of equilibrium equations and relations revealing the mechanical properties of integrated stresses, moments and generalized displacements on the contact part of the boundary. Accounting for complementarity type conditions owing to the contact of the plate with the inclined obstacle, a primal-dual variational formulation of the obstacle problem is derived. A semi-smooth Newton method based on a generalized gradient is constructed and performed as a primal-dual active-set algorithm. It is advantageous for efficient numerical solution of the problem, provided by a super-linear estimate for the corresponding iterates in function spaces. This article is part of the theme issue 'Non-smooth variational problems with applications in mechanics'. [ABSTRACT FROM AUTHOR]

Mechanized harvesting of fruit has been the ever-increasing trend in smart agriculture. However, the picking quality has been confined to the commonly-used unstructured planting for fruit trees. The robots can easily encounter the collisions with the dense branches and leaves during harvesting. The random spatial distribution of orchard obstacles can be highly influenced by the variation in the lighting conditions. It is very challenging on the real-time reconstruction of obstacles. In this study, a real-time reconstruction of orchard obstacles was proposed to combine the semantic segmentation and 3D point cloud analysis. Firstly, taking guava orchard as an example, the image acquisition was carried out using Intel RealSense D435i depth camera at a distance of about 15-50 cm from the guava fruit trees with a resolution of 640×480 in the orchard of Haiou Island Jiashuo Farm, Guangzhou City, Guangdong Province, China. Data enhancement was performed to improve the generalization and robustness of the model, according to the mirroring, luminance enhancement, luminance attenuation, adding Gaussian noise and pretzel noise. A total of 1,250 samples were obtained to randomly divided into the training, the validation and the test set in a ratio of 6:3:1, where there were 750 samples in the training set and 375 samples in the validation set; The test set was 125 samples. Then, a real-time semantic segmentation model was built using DeepLabV3+. The CoT module was introduced on the low-level feature map and high-level feature map of the encoder, with the MobileNetV3-large as the backbone network. The segmentation accuracy was improved on the thin obstacles like twig groups. The detail information of feature maps was strengthened to suppress the useless information. Furthermore, an edge-assisted loss function was proposed using the Sobel operator. Laplace edge loss function was used to further increase the accuracy of semantic segmentation, in order to improve the accuracy of picture edge segmentation. Next, the intrinsic parameters of the depth camera were combined to transform the semantic map of obstacles into a 3D point cloud. Statistical analysis was applied to remove the outliers. The voxelization was used to approximate the reconstruction of tree trunks and branches. Moreover, Euclidean clustering was employed to identify the individual 3D fruits. Among them, the minimum bounding box of the fruit was served as the reconstruction. Finally, the pose change matrix between the camera and the robot was obtained using the hand-eye calibration with a chessboard pattern. The minimum bounding box of the fruit and the voxelized cubes of branches and tree trunks were transformed into the working space of robot picking. The experimental results show that the MIoU (mean intersection over union) of obstacles in MobileNetV3-large-DeepLabV3+ was improved from 69.7% to 74.3% after the introduction of the CoT block, indicating an increase of 4.6 percentage points; The Sobel algorithm also considered both horizontal and vertical gradient information, indicating some anti-noise performance. The MIoU of the obstacle was further improved from 74.3% to 77.2%, indicating an improvement of 2.9 percentage points. The overall MIoU of the improved model was 7.0 percentage points, 0.6 percentage points, and 1.0 percentage points higher than those of Xception-DeepLabV3+, BranchNet, and LRASPP, respectively. There was 1.7 percentage points lower than BiSeNetV3; The ACC was 3.1 percentage points, 0.5 percentage points, and 0.6 percentage points higher than those of Xception-DeepLabV3+, BranchNet, and LRASPP, respectively, while there was 2.2 percentage points lower than BiSeNetV3; The FPS of the improved model was as high as 78.8 frames per second, which was faster than the comparison; The number of parameters was 4.4 M, which is 8% and 31% of Xception-DeepLabV3+ and BiSeNetV3, respectively, while BranchNet and LRASPP are 68% and 73% of the parameters in this paper, respectively. Besides, the IoU (intersection over union) values of the voxelized cubes for the fruit and branches were 65.7% and 56.6%, respectively, and the voxelization time was 0.34 s and 0.84 s, respectively. The better robustness and real-time performance can fully meet the obstacle avoidance requirements of guava picking robots. The real-time semantic segmentation of irregular obstacles was optimized to utilize more sophisticated attention modules or backbone networks. The finding can provide the better ways to enhance the effects of obstacle reconstruction. [ABSTRACT FROM AUTHOR]

Chemical bioreactions play a significant role in many of the microfluidic devices, and their applications in biomedical science have seen substantial growth. Given that effective mixing is vital for initiating biochemical reactions in many applications, micromixers have become increasingly prevalent for high-throughput assays. In this research, a numerical study using the finite element method was conducted to examine the fluid flow and mass transfer characteristics in novel micromixers featuring an array of pillars. The study utilized two-dimensional geometries. The impact of pillar configuration on mixing performance was evaluated using concentration distribution and mixing index as key metrics. The study explores the effects of pillar array design on mixing performance and pressure drop, drawing from principles such as contraction–expansion and split-recombine. Two configurations of pillar arrays, slanted and arrowhead, are introduced, each undergoing investigation regarding parameters such as pillar diameter, gap size between pillar groups, distance between pillars, and vertical shift in pillar groups. Subsequently, optimal micromixers are identified, exhibiting mixing efficiency exceeding 99.7% at moderate Reynolds number (Re = 1), a level typically challenging for micromixers to attain high mixing efficiency. Notably, the pressure drop remains low at 1102 Pa. Furthermore, the variations in mixing index over time and across different positions along the channel are examined. Both configurations demonstrate short mixing lengths and times. At a distance of 4300 μm from the inlet, the slanted and arrowhead configurations yielded mixing indices of 97.2% and 98.9%, respectively. The micromixers could provide a mixing index of 99.5% at the channel’s end within 8 s. Additionally, both configurations exceeded 90% mixing indices by the 3 s. The combination of rapid mixing, low pressure drop, and short mixing length positions the novel micromixers as highly promising for microfluidic applications. [ABSTRACT FROM AUTHOR]

This study conducted experiments to investigate the impact of bottom obstacles, specifically broad-crest weir-type and cylindrical obstacles, on the flow within a sewer pipe. It was observed that these two types of obstacles, when possessing the same cross-sectional area and length, exhibited nearly equivalent hydraulic responses for both supercritical and subcritical flows. The obstacle height was found to be the primary factor responsible for choking and the transition between different flow regimes. The results of the one-dimensional analysis show that the threshold value of obstacle height depends on the approaching flow conditions, including the Froude number and the filling ratio that is defined as the flow depth to the pipe diameter. In the context of a partially blocked sewer, the relationships established by using the one-dimensional model between the size of the bottom obstacle and the inflow characteristics enable the identification of flow regimes, assessment of reduced hydraulic capacity, and evaluation of local energy loss. The findings of this study elucidate the hydraulic behavior of obstructed sewers, contributing to the development of more effective strategies for the identification of obstructions through monitoring data. [ABSTRACT FROM AUTHOR]

The explosion venting experiments of hydrogen‐air premixed gas were carried out in a 1‐m3 cuboid container. The effects of the obstacles parallel to the vent on the structural response of the container during the explosion venting were investigated. The internal overpressure and acceleration of the vessel wall were captured by acceleration and pressure sensors, respectively. The time–frequency distributions of pressure and acceleration were obtained by a Short‐Time Fast Fourier Transform. The effects of obstacles on the dynamic structure response were studied by analyzing the internal overpressure, vibration acceleration, and high‐speed videos. With the increase of obstacles, the maximum overpressure and vessel vibration increased, and the maximum overpressure and maximum vibration acceleration appeared earlier. The vibration signals had two dominant frequencies, 300‐600 Hz and 900‐1200 Hz. The low‐frequency vibration (300–600 Hz) was induced by acoustic oscillation of the internal pressure. The high‐frequency vibration (900–1200 Hz) was a container resonance triggered by the coupling of the flame and the acoustic wave. As VBR increased, the duration of high‐frequency oscillations decreased gradually; the increase of obstacles would weaken the high‐frequency structural response of the container. The results can guide the design of hydrogen explosion protection and mitigation measures. [ABSTRACT FROM AUTHOR]

The present study attempts to test Bremond’s model The Logic of Narrative Possibilities and the Actantial Model of Greimas through explicating the narrative structure of the novel, Old Man and the Sea. In this research, a mixed method along with comparative study is mad through the application of these models to narratives structure of the novel. The research explores that both these reductionist models, though use different terminology, investigate the same issues and structure of the story. Hence, they have a strong association. This comparative study of structure inquiry has been used for the first time in broaching the structure of Old Man and the Sea. This study affirms the universality of these models that can be applied to all forms of narrative fiction. Hence it is recommended for the researchers to carry out further study by applying them to the structures of other forms of narrative fiction, like short stories, visual narratives and paintings. Thus, the research shows a new vista for researchers to probe further. [ABSTRACT FROM AUTHOR]

When there are dynamic obstacles in the environment, it is difficult for traditional path-generation algorithms to achieve desired obstacle-avoidance results. To solve this problem, we propose a robot navigation control method based on SAC (Soft Actor-Critic) Deep Reinforcement Learning. Firstly, we use a fast path-generation algorithm to control the robot to generate expert trajectories when the robot encounters danger as well as when it approaches a target, and we combine SAC reinforcement learning with imitation learning based on expert trajectories to improve the safety of training. Then, for the hybrid data consisting of agent data and expert data, we use an improved prioritized experience replay method to improve the learning efficiency of the policies. Finally, we introduce RNN (Recurrent Neural Network) units into the network structure of the SAC Deep Reinforcement-Learning navigation policy to improve the agent's transfer inference ability in a new environment and obstacle-avoidance ability in dynamic environments. Through simulation and practical experiments, it is fully verified that our method has a higher training efficiency and navigation success rate compared to state-of-the-art reinforcement-learning algorithms, which further enhances the obstacle-avoidance capability of the robot system. [ABSTRACT FROM AUTHOR]

In the development of lunar and planetary exploration rovers, risk assessment in on-site environments comprising fine regoliths and unevenly distributed rocks is essential. To prevent a rover from being stuck during its operation, one must understand the behavior of its wheel when it climbs over rigid obstacles in off-road environments. In this study, we apply an extended terramechanics model, which can reasonably describe the interaction between soft ground and vehicles, to analyze the obstacle-climbing behavior of rigid wheels. To describe the interaction between the wheel and a hard obstacle, we combine the penalty method with the extended terramechanics model. Subsequently, we verify the effectiveness of the proposed method by comparing its results with those of a traversing single wheel obtained from a laboratory experiment. Furthermore, we use the model to perform a multibody dynamics analysis on a simple rover, where its applicability to the examination of the overall performance of obstacle climbing is demonstrated. [ABSTRACT FROM AUTHOR]

Despite the economic advantages of introducing new agricultural technologies into the production system, their rate of adoption in Morocco remains relatively low. The objective of this article is to study the factors that hinder the adoption of these new technologies. We address the case of the recommended fertilizer doses (RFD). The study employs a probit model with a stratified random sampling approach.The data were collected from 297 farmers in the Casablanca-Settat region using a face-to-face interview method and analyzed through R software. The results of the study show that the main barriers are related to access to information and bank credit, government incentive, production orientation, distance to the market as well as age, and level of education. [ABSTRACT FROM AUTHOR]

This paper deals with generally routed, pre-bent cable-driven continuum robots (CCR). A CCR consists of a flexible backbone to which multiple disks are attached. Cables are passed through holes in the disk, and when pulled, the flexible backbone and the CCR can attain different shapes based on their routing and backbone configuration. An optimization-based approach, using minimization of strain energy, is shown to give good results for the pose and motion of the CCR and to determine contact with external objects. The pose, motion, and the contact obtained from the model are shown to match very well with experimental results obtained from a 3D-printed CCR. An algorithm is proposed to generate the pre-bent backbone for a CCR which on actuation can attain the desired shape. Using the algorithm, three 3D-printed CCRs with pre-bent backbones are fabricated and these are used to demonstrate a compliant gripper that can grip a spherical object similar to that done by tentacles, and another three-fingered gripper with straight backbone CCRs is used to orient a square object gripped at the end. [ABSTRACT FROM AUTHOR]

Visually impaired individuals may encounter some negative situations in their daily lives, both legally and religiously. While laws deal with the legal aspect, Islamic law deals with the religious aspect. In order to minimize the difficulties that visually impaired people may face in their daily lives, Islamic law has made some flexible provisions based on the principle of facilitation. This work, which we are introducing, deals in detail with the information on the provisions for the visually impaired in ibādāt, muāmalāt, munāqahāt - mufārekāt, ukūbāt and some other issues by including the views of the four major madhhabs. [ABSTRACT FROM AUTHOR]

The modeling of blind people's behavior is an important topic in pedestrian evacuation dynamics. In order to study movement characteristics of blind people in evacuation process and the effect of indoor obstacles on the evacuation efficiency of blind people, an extended cellular automata model is proposed to simulate blind people evacuation by considering the influence of obstacles. The control variable method is adopted to study the effect of indoor obstacles on the blind evacuation efficiency rule. The numerical simulation is applied to analyze the evacuation process of blind people under different setting (e.g. the location, size and other factors) of obstacles and different evacuation scenarios. The shunt effect of obstacles is discussed and the layout strategy of obstacles is optimized. The results show that the longitudinal obstacles in front of the exit can effectively play the diversion role of obstacles when the obstacle is at a certain distance from the exit, which will improve the evacuation efficiency of the blind. Furthermore, a horizontal obstacle of appropriate length can constrain the trajectory of the blind people and improve the efficiency of evacuation, but when the horizontal obstacle is too long, it will induce extra jam on both sides of the obstacle and hinder the evacuation of the blind. The finding can provide the theoretical basis for the blind people's organization, management and the optimization of evacuation strategies during an emergency. [ABSTRACT FROM AUTHOR]

Copyright of Turkish Journal of Film Studies / Türkiye Film Araştırmaları Derneği is the property of Turkish Journal of Film Studies / Turkiye Film Arastirmalari Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It is shown that the front of the flame of a thoroughly mixed diluted methane-oxygen mixture at 298 K and 100–300 Torr propagating to the ends of hollow cylindrical and conical obstacles does not form a von Kármán path (vortex shedding) behind them; however, this instability occurs under the same conditions in the flow of hot products after obstacles. The reason that vortex shedding is not observed behind an obstacle during flame propagation but appears in the course of propagation of a reflected stream of hot products is that thermal conductivity reduces the curvature of the flame and leads to its stabilization. Indeed, the convex areas of the chemical reaction zone in a combustible mixture give off more heat in relation to cold ones than in a flat flame: the heat from them is not only transmitted forward in the direction of flame propagation but also in the lateral directions. The resulting cooling of the reaction zone causes the flame regions that burst forward to lag behind. The opposite situation is observed in concave areas, where the temperature rises for the same reasons. The rate of reactions increases and they spread forward faster as the flame spreads. Thus, the surface of the curved front of the flame is evened out. In other words, thermal conductivity has a stabilizing effect on a curved flame. This effect is missing in non-reactive gas. This effect is absent in a nonreacting gas. Calculations based on the acoustic approximation of the Navier–Stokes equations for a compressible reacting medium make it possible to take into account the main observed feature of the flame front approaching an obstacle in the form of a cylinder: vortex shedding is not observed behind the obstacle during flame propagation. Thus, a qualitative model allows obtaining both the mode of the emergence of a von Kármán instability in a chemically inert gas and its absence during flame propagation. [ABSTRACT FROM AUTHOR]

The present study investigates forced convection heat transfer of rarefied flow within a microchannel containing obstacles using the thermal lattice Boltzmann method using a double distribution function model and BGK approximation. Slip velocity and temperature jump conditions were employed across microchannel walls. The microchannel temperature and velocity input are constant. The microchannel configuration has three obstacles imposed along the lower microchannel wall. The study simulates rarefied fluid flow and heat transmission of forced convection inside the microchannel, considering separation between obstacles as the primary study objective. The findings represent the distribution of temperature and velocity. In addition, temperature jump and slip velocity in the function of Knudsen numbers were also represented. The findings highlight the substantial influence of barriers on temperature and velocity. As the distance between obstacles drops, the temperature diminishes. Additionally, a rise in separation distances significantly aids in the dropping of velocity. The results reveal a significant reduction in slip velocity as Knudsen numbers increase across the microchannel length. The outcomes of the present investigation could assist and be used as a cooling solution for various technologies, such as microelectronics and nanoelectromechanical systems. Additionally, the suggested configuration might be utilized to improve microfluidic device design.

Numerical modeling of the interaction of a vortex ring with a normally located flat obstacle was performed based on the nonstationary Navier–Stokes equations, for discretization of which the finite volume method was used. A qualitative picture of the change in the structure of a vortex ring during its interaction with the obstacle is presented. The distributions of pressure in time on the obstacle and the change in the longitudinal force acting on the obstacle are determined. [ABSTRACT FROM AUTHOR]

Numerical investigations were carried out to study the arrangement of an obstacle with a critical block ratio on the diffraction and subsequent reflection characteristics of cellular detonation using the in-house solver DCRFoam. Detonation waves were formed in a two-dimensional 61.6 mm wide tube filled with 2H 2 +O 2 +7AR mixtures whose initial pressure and temperature were 6.67 kPa and 298 K. The results showed that the arrangement of the obstacle had a significant impact on the downstream structures. When the obstacle was symmetrical about the tube central, regular cells that were a time larger than those upstream of the obstacle could be observed downstream of the obstacle. When the obstacle was located on one side of the tube, the cell structure of single-head detonation was left downstream of the obstacle. When the obstacle deviated from the tube central by 1/4 width of cells upstream of it, a distorted rhombic cell structure could be primarily observed, which then evolved into that like a single-head detonation. The propagation speed and peak pressure of the leading shock were independent of the obstacle arrangements. For regular cell structures, the averaged velocities along the cell central in a period were consistent with those in a cell upstream of the obstacle. • Diffraction and reflection details of cellular detonation were numerically analyzed. • Cellular structure downstream of the obstacle was affected by obstacle arrangement. • Propagation velocity downstream of the obstacle was independent of obstacle arrangement. [ABSTRACT FROM AUTHOR]

This paper aims to compare and evaluate various obstacle approximation techniques employed in the context of the steady incompressible Navier–Stokes equations. Specifically, we investigate the effectiveness of a standard volume penalization approximation and an approximation method utilizing high viscosity inside the obstacle region, as well as their composition. Analytical results concerning the convergence rate of these approaches are provided, and extensive numerical experiments are conducted to validate their performance. [ABSTRACT FROM AUTHOR]

Gravity currents modify their flow characteristics in the presence of an obstacle. Also, the flow path to the dam reservoirs is not always direct. Since no studies have addressed the feedback between the hydrodynamics of a gravity current in a curved channel and the location effects of the obstacle, in this research, a Lock-exchange density current flows in a 120 ∘ bending channel. The numerical simulation has been performed using OpenFOAM software. The models include no-obstacle curved channel and a curved channel with an obstacle in different positions concerning the increased radius of the curved channel. Results indicated that the obstacle directed the concentration towards the banks, with its maximum value tending from the outer to the inner bank, especially in the tail. The tail longitudinal velocity maximized near the channel bed in areas far from the obstacle, and in the outer bank in areas near it. The secondary flow reduces its lowest and most different pattern observed around the obstacle. In displacing the latter, if the front has at a certain distance, the secondary flow does not change much, but if it has at the channel end, the post-obstacle secondary flow would increase as the obstacle neared the Lock. [ABSTRACT FROM AUTHOR]

Numerical methods are very useful for predicting water levels, velocities and flow rates in hydraulic systems. The Saint-Venant system of equations, which is a hyperbolic partial differential system, is widely used in the modelling of a flood wave due to a dam failure. In this study, two explicit finite difference Lax-Friedrichs and modified Lax-Friedrichs numerical schemes are used to simulate the failure wave of a dam. The calibration of the obtained results is done in relation to experimental measurements and numerical results existing in the literature specialized in this field of research. The experimental set-up consists of a water reservoir that simulates the reservoir of a dam, followed downstream by a horizontal dry bottom section, a triangular bottom sill with steep slopes and a small tide of water at rest after the triangular obstacle which ends with a vertical diaphragm. The simulation obtained results with the new formulation of the Lax-Friedrichs numerical scheme showed good agreement with the simulated, experimental and numerical results of other researchers. [ABSTRACT FROM AUTHOR]

[Objective] Compared with conventional gas fuel, hydrogen is more susceptible to explosion. Meanwhile, the existence of obstacles notably stimulates hydrogen combustion and accelerates flame propagation, causing more serious consequences of accidents. To reduce destructive damage caused by hydrogen combustion under obstacle conditions, it is particularly important to reveal the influences of different obstacle conditions on the characteristics of flame propagation of hydrogen. [Methods] Based on large eddy simulation, the hydrogen/air combustion and explosion processes under different obstacle shapes and blockage rate conditions were numerically simulated.Focus was given to the research on different flame propagation velocities caused by different obstacle shapes and the sensitivity to blockage rate changes. [Results] Under low blockage rate, grid-type obstacles had a stronger destructive effect on the regular flow field at the flame front than single-side obstacles, and as the number of voids in grid-type obstacles increased, their destructive effect on the flow field motion further intensified, making it difficult for the flame front to recover to a regular state. When the blockage rate went up, the difference of the shapes of obstacles became insignificant in causing damage to the regular flow field, and the flame front was continuously distorted under all obstacle conditions. As the blockage rate continued to increase, single-side obstacles brought higher peak flame propagation velocity than grid-type obstacles. At the same blockage rate, the mechanism of flame acceleration by grid-type obstacles can be changed by adjusting the single void area to enhance the acceleration effect. [Conclusion] The shape and blockage rate of obstacles are the key factors influencing the state of flame front behind obstacles.The single-side obstacle is more sensitive to the blockage rate,while the grid-type obstacle has higher acceleration potential.The research results provide basic reference data for the prevention and control of hydrogen fire accidents and serve as a reference for the design of hydrogen power systems.

Günümüzde sıklıkla tartışılan ve en çok ihtiyaç duyulan şeylerden biri de adâlettir. Adâletin tanımı, mahiyeti ve ölçütü, öteden beri âlimlerin, filozofların, düşünürlerin ilgi alanına girmiş, kalem ve düşünce sahibi her insan bu konuda bir şeyler yazma, söyleme gereği duymuştur. “Adâlet nedir?”, “Adâletin temel ölçütü nedir?”, “Adâletli insan kimdir?” ve “Adâleti engelleyen durumlar nelerdir?” gibi sorular ve sorunlar tarih boyunca hep insanlığın gündemini meşgul etmiştir. Kimi düşünürler, adâleti, “denge” diye kimileri, “mücâzât ve mükâfatta eşitlik”, kimileri ise “hak ve hukuk” kavramlarıyla açıklamıştır. İslâm düşüncesinde ise adâlet; “adl”, “kıst”, “ihsan”, “takvâ” gibi ahlâk ve hukuk alanını ilgilendiren kavramların ışığında, teorik bir çerçevede tartışılmıştır. Büyük oranda Kur’ân ve hadislerden hareketle şekillenen teorilere göre insanı yaratan Allah olduğu gibi adâletin mahiyetini, neliğini ve ölçütünü belirleyen de Allah’tır. Allah mutlak olarak adâletlidir. Haksızlığı ve zulmü kendisine yasaklamıştır. İnsanın adâleti ayakta tutan bir varlık olması için, fıtratını adâlet erdemiyle donatmış ve adâleti tesis eden hükümler vazetmiştir. Adâlet, batı medeniyetini temsil eden filozofların kabulünün aksine tanımlanabilen ve mümkün olan bir şeydir. Tarih boyunca düşünürler adâletle ilgili düşünceler üretmiş, teoriler geliştirmiştir. Ama bu düşünceler ve teoriler bir yönüyle hep eksik kalmıştır. Zira insan; bütün zamanları, şartları ve insanın temel ihtiyaçlarını kapsayacak, kuşatacak ne ilme ne de kudrete sahiptir. Adâlet duygusunu insanın fıtratına yerleştiren, onu insanda bir değer ve meleke olarak var eden Allah’tır. İnsan, doğuştan adâleti ihsas ettiren duygu ve düşüncelerle donanımlı olarak doğmuştur. Bunun bir sonucu olarak; hangi eğitim seviyesinde olursa olsun hangi toplumsal statüde bulunursa bulunsun her insan adâletli bir eylem ile onun zıddı olan zulmü birbirinden ayırt edebilecek bir kabiliyete sahiptir. İslâm düşünce tarihi boyunca adâlet kavramı ve onunla dolaylı olarak bağlantılı olan tikel kavramlar İslâm hukuku, tefsir ve hadis gibi ilim dallarının ilgi odağında bulunmuştur. Adâlet kavramı; ferdi adâlet, sosyal adâlet, eşitlik, denge ve takvâ gibi temel kavramlarla bağlantılı olarak ele alınmış; adâletin mahiyeti, ölçütü ve korunmasına dair müesseseler geliştirilmiş ve teoriler önerilmiştir. İslâm düşüncesinde adâletin mahiyetine dair teoriler ileri sürülmesinin yanında onun insanın fıtratında yer alan bazı duygularla bağlantısına kuvvetle işaret edilmiştir. Âyet ve hadislerde adâlet doğrudan tanımlanmamakla birlikte adâletin mahiyetine ve adâletin sağlanması ve önündeki bazı manilere göndermelerde bulunulmuştur. Âyetlerde adâlet hep, “Allah’tan gereği gibi korkmak ve Âhiret bilinci” demek olan takvâyla birlikte anılmıştır. Takvânın adâletin bir teminatı olduğu, gerçek anlamda adâletin ancak takvâlı bireylerin çabasıyla ayakta kalacağı vurgulanmıştır. Adâletle ilgili hükümler genellikle emir formunda gelmiştir. Adâletle ilgili emir sîgaları bir arada değerlendirildiğinde âdil davranmanın tıpkı namaz kılmak, oruç tutmak, zekât vermek gibi farz olduğu gerçeği ortaya çıkmıştır. Bu çalışmada öncelikle adâletin Allah tarafından insanın fıtratında var edilmiş bir erdem olduğu, bu erdemin büyük oranda takva bilinciyle canlı tutulabileceği gerçeği üzerinde durulacaktır. İslâm düşüncesi çerçevesinde adâletin mahiyeti, gerçekleşmesi ve adâletin sağlanmasının önündeki sosyo-ekonomik statü, aile ve akrabalık bağları, acıma ya da düşmanlık duygusu, dinî aidiyet ve mali külfet gibi engeller (tutum/davranış) değerlendirilecektir. Bunun yanı sıra adâletin sadece hukuk sahasını ilgilendiren bir davranış ve tutum olmadığı; ahlâki duruş, aklıselim, dengeli davranış ve takvâ bağlamında ele alınmasının gereği vurgulanacaktır.

In the field of hydrogen safety and combustion, the effect of obstacles on hydrogen deflagration is a topic of general interest to scholars. In previous studies, scholars usually used uniform obstacles under various operating conditions and obtained conclusions by changing their number and positions. However, in practice, the shapes of obstacles at an accident site are often not the same and regular. In this paper, a series of obstacles with variations in length were investigated, and the effects of the obstacles on hydrogen deflagration under different working conditions were analyzed. The configuration of the obstacles with gradually increasing lengths amplified the vortices in the flow field so that the propagation direction of the flame front surface was reversed after passing three obstacles. The variations in the lengths of the obstacles had a significant stretching effect on the propagation of the flame and a considerable acceleration effect on the propagation speed of the flame. The main reason for the acceleration was the rapid propagation of the flame achieved by the vortex when rupture occurred. The change in the pressure gradient that occurred at the center of rotation caused rapid movement of the combustion gases, which ultimately led to an increase in the flame propagation speed. A configuration with gradually increasing lengths of the obstacles promoted the overpressure. A configuration with gradually decreasing lengths of the obstacles suppressed the overpressure. The reason for the formation of the local high-pressure area was that unburned gas was accumulated there by pressure waves and the obstacle walls, and then the thermal expansion formed a high pressure. The Rayleigh–Taylor and Kelvin–Helmholtz instabilities caused the overpressure to rise further. The results can provide a theoretical basis for hydrogen transportation, storage, and safety.

With advances in unmanned aerial vehicle (UAV) technologies, they have been put to use in a wide variety of scenarios, including emergency surveillance and disaster management. However, their widespread usage is still limited due to their expensive nature. Only user-piloted UAVs are extensively used still today; but their low-budget design leads to lack of auto-guidance and cooperative functions in both line-of-sight and obstacle-sensitive operations. This paper presents a new approach of self-guidance in these budget UAVs for stable maneuverability even in the obstacle-sensitive surroundings. Further, the paper additionally incorporates cooperative functioning in such self-guided budget UAVs for completing collaborative tasks of emergency surveillance. Comparative testbed results show the cost-effective benefits of the proposed methods and the precise working abilities in no-obstacle as well as obstacle-sensitive sites. [ABSTRACT FROM AUTHOR]

In this paper, we study a spatially periodic bistable-type reaction–diffusion equation in so-called exterior domains Ω = R N \ K , where K ⊂ R N is a compact set and denotes an obstacle. For any direction e ∈ S N - 1 , if the spatially periodic bistable reaction–diffusion equation in R N admits a moving pulsating front (i.e., the wave speed is nonzero), we first prove the existence and uniqueness of entire solution in the exterior domain Ω , which is emanated from the moving pulsating front. Assuming further that the propagation of the entire solution is complete (i.e., convergence to 1), we prove that the entire solution is a transition front connecting 0 and 1 and is trapped between two translates of the moving pulsating front as time goes to + ∞ . In particular, applying a Liouville-type result, we prove that the entire solution can eventually recover to the same moving pulsating front after crossing the obstacle K by providing some appropriate hypotheses. [ABSTRACT FROM AUTHOR]

In the field of hydrogen safety and combustion, the effect of obstacles on hydrogen deflagration is a topic of general interest to scholars. In previous studies, scholars usually used uniform obstacles under various operating conditions and obtained conclusions by changing their number and positions. However, in practice, the shapes of obstacles at an accident site are often not the same and regular. In this paper, a series of obstacles with variations in length were investigated, and the effects of the obstacles on hydrogen deflagration under different working conditions were analyzed. The configuration of the obstacles with gradually increasing lengths amplified the vortices in the flow field so that the propagation direction of the flame front surface was reversed after passing three obstacles. The variations in the lengths of the obstacles had a significant stretching effect on the propagation of the flame and a considerable acceleration effect on the propagation speed of the flame. The main reason for the acceleration was the rapid propagation of the flame achieved by the vortex when rupture occurred. The change in the pressure gradient that occurred at the center of rotation caused rapid movement of the combustion gases, which ultimately led to an increase in the flame propagation speed. A configuration with gradually increasing lengths of the obstacles promoted the overpressure. A configuration with gradually decreasing lengths of the obstacles suppressed the overpressure. The reason for the formation of the local high-pressure area was that unburned gas was accumulated there by pressure waves and the obstacle walls, and then the thermal expansion formed a high pressure. The Rayleigh-Taylor and Kelvin-Helmholtz instabilities caused the overpressure to rise further. The results can provide a theoretical basis for hydrogen transportation, storage, and safety. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of High Pressure Physics is the property of Chinese Journal of High Pressure Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the diffusion characteristics and laws of hydrogen leakage in confined spaces are investigated using a combination of numerical simulations and experiments, and a small-scale cube model (dimensions: 0.47 m×0.33 m × 0.20 m) is used. The effects of leak source location, obstacles, leak hole size and shape on hydrogen diffusion and concentration evolution were investigated. The results show that the top funnel is sprayed vertically downward, the diffusion velocity decreases rapidly under the blocking effect of air and buoyancy force, and the momentum of the airflow is exchanged. During the injection phase, the leaking gas is mainly subjected to strong buoyancy forces and the hydrogen concentration shows a stratification effect. When the injection stops, the concentration difference decreases and eventually the hydrogen concentration reaches a steady state. The obstacle model in turbulence (4.3%) increases the concentration difference by a factor of about three compared to the empty room model (1.7%), which seriously affects the diffusive behavior of hydrogen. The obstacle in laminar flow model (10.4%) has almost the same concentration difference as the empty room model (10.2%). Rectangular leakage holes have a greater initial kinetic energy and diffuse more widely and faster. • Effects of obstacles, leakage hole size and shape on concentration were studied. • The rate of diffusion is reduced due to the blocking effect of air and buoyancy. • Hydrogen concentration shows a stratification effect in the presence of buoyancy. • Obstacles cause loss of gas kinetic energy and delay the averaging time. • Rectangular leakage holes have a large gas diffusion range and fast diffusion rate. [ABSTRACT FROM AUTHOR]

The second leading cause of death in the elderly and severe injury for the visually impaired is due to falls. Many studies, reveals that the usage of conventional assistive cane devices is critical in reducing the risk of falls. The conventional aids exhibit serious adverse effects that contribute to falls, even though it provides physical support as well as supplementary sensing feedback to patients. The visually impaired people mostly use white cane or guide dogs to provide directions while walking. In order to enhance the features of existing white cane, a smart assisting cane is designed to achieve the goals of obstacle avoidance and fall detection efficiently. The existing smart cane informs the user whether the obstacle is present or not, but the user have no idea about what type of obstacle it is. Thus, in this work, a system which detects elevated and depressed surface and aids the user while approaching a staircase is designed. This system also detects overhead or hanging obstacles. In addition to that to prevent fall, a moisture sensor is placed at the end of the stick to detect slippery surfaces and an additional ultrasonic sensor is placed for identifying pit. These sensors are interfaced with Arduino. Elevated surface and drop off surfaces are also detected by comparing the difference in delay of signals from the two sensors. The main objective of this work is to design a smart cane which helps the blind user to get aware of what type of obstacle he/she is approaching and alerting them with voice output. The systems also gives alerts the user’s relative position by sending the location of the user in case of any abnormal or emergency situations. [ABSTRACT FROM AUTHOR]

The difficulties experienced by students in studying derivative material are difficulties understanding the definition of derivatives and representations of these derivatives. Derivatives are a material that is quite difficult to develop mathematical creative abilities because they have many functions and symbols. This difficulty indicates a barrier to thinking in students. This research is descriptive qualitative research with five research subjects of Tadris Mathematics at the Curup State Islamic Institute. Each student can think creatively mathematically on the indicators of flexibility, fluency, and originality, but the levels are different. The level of mathematical creative thinking ability can depend on the questions or problems and the material being studied. However, one of the indicators of the ability to think creatively mathematically, which is very weak for students, is originality because students seem rigid with what they have obtained from lecturers and books. Students find it difficult to come up with ideas in solving problems. Barriers to thinking creatively mathematically can occur due to several factors, including 1) due to a lack of prior knowledge of students in understanding problems and determining ideas in planning solutions; 2) a lack of strong concepts possessed by students. One way for lecturers to overcome these obstacles is to provide scaffolding. The provision of scaffolding is carried out using Treffinger learning with several stages, namely basic tools, practice with process, and working with real problems. In practice with process stage, students solve problems by using analogical reasoning to develop their mathematical creative thinking abilities. The stages of analogical reasoning used to consist of the stages of recognition, representation, structuring, mapping, applying, and verifying. This study's findings are that two new stages are added to the early stages of analogical reasoning, namely the stages of recognition and representation. [ABSTRACT FROM AUTHOR]

One of the most discussed and most needed things today is justice. The nature, definition, and limits of “justice” has always been in the field of interest of scholars, philosophers, and thinkers, and every scholar who felt the need to write and say something about it. Questions and problems such as “what is justice?”, “what is the basic criteria of justice?”, “who is the just man?”, and “what are the obstacles that prevent justice?” have always occupied the agenda of humanity throughout history. Some thinkers have explained justice as “balance”, some with the concepts of “equality in punishment and reward” and some with the concepts of “right and law”. In Islamic thought, justice is defined by moral and ethical values such as “adl”, “qist”, “ihsan”, and “taqwa”. It has been discussed in a theoretical framework regarding the concepts related to the field of law. According to the theories that are shaped largely by the Qur’an and hadiths, it is Allah who created man as well as Allah who determines the nature, characteristics, and criteria of justice. Allah is absolutely Just. He has forbidden injustice and oppression to Himself. For humans to be a being that sustains justice, Allah has equipped human nature with the virtue of justice and has issued the rules and provisions that establish justice. Justice is something that can be defined and that is possible, contrary to the acceptance of philosophers representing Western civilization. Throughout history, thinkers have produced ideas and developed theories about justice. But these thoughts and theories have always remained incomplete in one respect, because man has neither the knowledge nor the power to cover and encompass all times, conditions and basic needs of man. It is Allah who bestows the sense of justice to human nature and creates it in man as a value and ability. Man is born equipped with the feelings and thoughts that innate justice. As a result of this; Regardless of their educational level and social status, every human being has the ability to distinguish between a just action and its opposite, injustice. Throughout the history of Islamic thought, the concept of justice and the particular concepts that are indirectly related to it have been at the center of attention of branches of sciences such as Islamic law, tafsir, and hadith. The concept of justice has been dealt with in connection with the basic concepts such as individual justice, social justice, equality, balance, and piety; Institutions have been developed and theories have been proposed regarding the nature, criteria, and protection of justice. In addition to putting forward theories about the nature of justice in Islamic thought, its connection with some emotions in human nature has been strongly pointed out. Although justice is not defined directly in the verses and hadiths, references are made to the nature of justice, the provision of justice, and some obstacles before it. In the verses, justice is always mentioned together with taqwa, which means “piety, fearing Allah properly, awareness of the Hereafter”. It has been emphasized that taqwa is a guarantee of justice and that justice in the real sense can only survive with the efforts of pious individuals. Provisions on justice often came in the form of commands. When the tenses and forms commanding justice are evaluated together, it becomes clear that acting justly is obligatory, just like performing prayers, fasting, and giving zakat. In this study, the nature of justice, its realization, and the obstacles (attitude/behavior) before the provision of justice such as socio-economic status, family and kinship ties, feelings of pity or enmity, religious belonging, financial burden will be evaluated within the framework of Islamic thought. In addition, the possibilities of dealing with justice in the context of moral attitude, common sense, balanced behavior, and taqwa, which is the fear of God, will be investigated. [ABSTRACT FROM AUTHOR]

This paper aims to discuss the common obstacles detected during the maintenance of railway communication optical cables, and explore the methods to analyze and locate and deal with such obstacles. According to the situation of fiber core blocking, the obstacles of optical cables are divided into several types, such as complete blocking, partial blocking, and excessive fiber attenuation. The causes of optical cable obstacles are analyzed, and are divided into natural disasters, external forces, human factors, and cable defects. For diff erent types of optical cable obstacles, corresponding handling methods are proposed, including the principles for dealing with faults and obstacles, the sequences for achieving emergent reconnection and recovery, and the methods for locating and dealing with cable fault points. This paper emphasizes the importance of day-to-day maintenance management of railway communication optical cable lines, to ensure the safe operation of railway communication equipment, so as to guarantee the safety of railway transportation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract In this study, we examine whether retailers in Eastern Europe and Central Asia found corruption, courts, tax administration, tax rates, political instability, and business licensing/permits as an obstacle to their firm. We focus on a specific period when retailers all around the world suffered in terms of revenues and profits. This is the period surrounding the 2008-2009 global crisis. We first examine the degree to which retailers see each of these factors as an obstacle in the pre-crisis period. Were they seeing each of these factors as a minor, moderate, major, or very severe obstacle, or were they seeing them as no obstacle? Then, we compare our findings to our findings in the post-crisis period. Had their perceptions improved or worsened after the crisis ended? We expect to see improvements in each of these areas due to governments’ efforts to lessen the burden on retailers. Our results show that retailers’ perceptions of all six factors had improved post-crisis. These findings confirm that, overall, governments were successful in reducing the burdens on retailers.