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Travelling salesman problem (TSP) is a well known combinatorial optimization problem which has drawn colossal attention due to its eclectic range of applications. In this article, we have proposed two modified versions of intelligent water drops (IWD) algorithm. The first one is the enhanced IWD (e-IWD) algorithm to solve single objective TSP. In the second modification, e-IWD algorithm has been extended to enhanced multi-objective IWD(e-MIWD) algorithm for solving multi-objective TSP. In order to achieve a better exploration capability in both of the proposed algorithms, the soil and velocity parameters of a randomly selected water drop are updated after every iteration of the algorithm when it traverses all the intermediate vertices for a tour. The proposed algorithms have been compared with some other existing similar algorithms on different benchmark instances of TSPs. Furthermore, we have addressed the TSP for both single and multiple objectives under uncertain environment.

There were examined the problems of passage of the regulated parts of a road. There were investigated the changes of a traffic movement intensity in Lutsk (Ukraine) during the spread of Covid-19 pandemic. The graphic dependences of the drivers’ actions estimation while passing the traffic lights objects on a chosen movement route at the beginning of quarantine measures, during the least movement intensity and at the increasing of movement intensity, were obtained. A method of increasing of a possibility of the traffic lights objects nonstop passage was offered.

The pursuit of studying the quadratic minimum spanning tree (QMST) problem has captivated numerous academics because of its distinctive characteristic of taking into account the cost of interaction between pairs of edges. A QMST refers to the minimum spanning tree, which is a graph that is both acyclic and minimally connected. It also includes the interaction cost between a pair of edges in the minimum spanning tree. These interaction costs can occur between any pair of edges, whether they are adjacent or non-adjacent. In the QMST problem, our objective is to minimize both the cost of the edges and the cost of interactions. This eventually classifies the task as NP-hard. The interaction costs, sometimes referred to as quadratic costs, inherently exhibit a contradictory relationship with linear edge costs when solving a multi-objective problem that aims to minimize both linear and quadratic costs simultaneously. This study addresses the bi-objective adjacent only quadratic minimum spanning tree problem (AQMSTP) by incorporating the uncertain nature of the linear and quadratic costs associated with the problem. The focus is on the interaction costs between adjacent edges. Consequently, we have introduced a multi-objective problem called the uncertain adjacent only quadratic minimum spanning tree problem (mUAQMSTP) and formulated it using the uncertain chance-constrained programming technique. Afterwards, two MOEAs—non-dominated sorting genetic algorithm II (NSGAII) and duplicate elimination non-dominated sorting evolutionary algorithm (DENSEA)—and the traditional multi-objective solution approach, the global criterion method, are employed to solve the deterministic transformation of the model. Finally, we provide a suitable numerical illustration to substantiate our suggested framework. [ABSTRACT FROM AUTHOR]

The results of the influence of a range of process liquids on the formation of strengthened nanocrystalline structures in the surface layers of steel samples with different carbon content during thermo-deformation treatment are presented. The liquids were mineral oil; mineral oil with active additives containing polymers; water; and an aqueous solution of mineral salts based on magnesium and calcium chlorides. The thickness and hardness of the nanocrystalline layer increased with increasing steel carbon content. The thickness and microhardness of Steel C45 are 230–240 μm and 8.6 GPa, respectively, when using mineral oil with AAP, 110–120 μm and 7.2 GPa, respectively, when using mineral oil alone, and for steel CT80 when using mineral oil, they are 180–200 μm and 9.1 GPa, respectively (C45 and CT80 refers to engineering steels). The process liquid is decomposed into its component chemical elements by the high temperatures and pressures in the contact zone of the tool with the treated surface. It also gives off active hydrogen, which diffuses into the surface layer of the metal and significantly affects its formation. It was established that the greatest thickness and hardness of the layers were obtained after processing pre-hydrogenated samples. The choice of process fluid is critical during thermo-deformation treatment. [ABSTRACT FROM AUTHOR]

The Indian Railways Reservation System (IRRS) is one of the world's busiest reservation systems of railway tickets. Recently, the COVID-19 pandemic situation has severely impacted the Indian Railway's (IR) transportation, which eventually has enforced the IR to alter the passenger reservation system. This research attempts to evaluate and analyse the factors that modify the IRRS. In this research, a rough set-based Data Mining Scaffolding (DMS) has been proposed. Here, the relevant preferential information related to the IRRS is managed by introducing a multi-criteria decision-making (MCDM), where a decision-maker (DM) can make a decision based on several decision rules. The effectiveness of the proposed DMS is explained by gathering realistic data of 26 trains, which run between railway stations of two metro cities of India during the COVID-19 pandemic period., Author(s): Haresh Kumar Sharma [1]; Saibal Majumder [2]; Arindam Biswas [3]; Olegas Prentkovskis (corresponding author) [4]; Samarjit Kar [5]; Paulius Skačkauskas [4] 1. Introduction Since the inception of the Rough [...]

This study proposes a hybrid multiple criteria decision making (MCDM) methodology for evaluating the performance of the Indian railway stations (IRS). Since the customers are heterogeneous and their requirements are often imprecise, the evaluation process is a critical step for prioritizing the IRS. To improve the existing approaches, an efficient evaluation technique has been proposed by integrating rough numbers, analytic hierarchy process (AHP) and multi-attribute border approximation area comparison (MABAC) methods in rough environment. The relative criteria weights based on their preferences given by experts is determined by rough AHP whereas evaluation of the alternatives based on these criteria are done by the modified rough MABAC method. A case study of prioritizing different railway stations in India is provided to demonstrate the efficiency and applicability of the proposed method. Among different criteria “proactively” is observed to be the most important criteria in our analysis, followed by ‘Railfanning’ and ‘DMO’ is found to be the best among the forty IRS in this study. Finally, a comparative analysis and validity testing of the proposed method are elaborated and the methodology provides a standard to select IRS on the basis of different criteria.

Dynamically changing economic conditions influence the growing demand of various freights transportation. Inevitably, the demand for heavy and oversized freight transportation is increasing, which is quite problematic. In many cases, it is very difficult to standardize the technology of heavy and oversized freight transportation. Decisions are necessary, which would allow to deliver heavy or oversized freight to the destination place, allocating fewer funds as possible for infrastructure improvements, choosing the most appropriate mode of transport for such freight transportation or using advantages of multimodal (combined) transport. In this article there will be selected methodology of heavy and oversized freight transportation system, carrying heavy and oversized freight by road transport. There will also be made an approval of this methodology, based on a hypothetical route within Lithuanian territory.

During the TDT of 41Cr4 steel specimens, a uniformly reinforced white layer with a nano-crystalline structure is formed in the surface layers. The wear resistance of sliding friction without the lubrication of a pair of steel 41Cr4—grey cast iron EN-GJL-200 (EN) under the face-to-face ("ring-ring") scheme has been studied. It is revealed that when the sliding velocity changes from 0.25 m/s to 4 m/s and the unit load changes from 0.2 MPa to 1.0 MPa, a pair with a reinforced surface layer on 41Cr4 steel specimens and unreinforced specimens of EN-GJL-200 (EN) grey cast iron has a higher wear resistance than an unreinforced pair. The wear resistance increases for both reinforced and not reinforced specimens operating in a friction pair. [ABSTRACT FROM AUTHOR]

The main regularities in fatigue fracture of the railway axle material - the OSL steel - are found in this paper. Micromechanisms of fatigue crack propagation are described and systematized, and a physical-mechanical interpretation of the relief morphology at different stages of crack propagation is proposed for fatigue cracks in specimens cut out of the surface, internal and central layers of the axle.

Reliability and maintenance analysis in transport focus on the main objective of accident and incident investigations that benefit to better understanding of the causes of accidents and prevention of them in the future. The conducted research presents theoretical and experimental research on composite pneumatic tire used in transport engineering. The approach of the numerical simulation sequence which is offered in this research facilitates engineers in efficient determination of the dynamic properties and behaviour of vehicle tire at design stage. The tire materials have been tested by employing piezoelectric micro-vibration tests and frequency analyses. The Finite Element Method used for numerical simulation in combination with experimental measurements based on optimization by material frequency response, was applied in modelling tire material behaviour avoiding problems of composite structure modelling. The obtained results indicate that the offered methodology can be used in numerical simulation of composite tire investigation and considering material viscos-elastic properties. [ABSTRACT FROM AUTHOR]

From the mid-1990s onwards, the concept of competitiveness was introduced to firms at the level of countries, regions, and cities. It was used as an index of the success and superiority of places. The present study used quantitative (survey) and qualitative methods in the framework of the exploratory paradigm to achieve key driving variables affecting the competitiveness of Kermanshah. The present study was applied in terms of its purpose and descriptive–analytical nature and research method. The study's statistical population consisted of experts related to the Kermanshah competitiveness index, which studied 30 experts using the snowball method. MICMAC software was used to analyze the research data. Findings indicated that out of a total of 54 variables affecting the competitiveness of Kermanshah, 11 variables were in this group, which were the role of Kermanshah city in the power structure (MIN1); geographical and strategic location (MIN4); national, regional, and local plans (MIN5); management (MIN6); clean and healthy air (ENV1); potential sources of soil and water (ENV2); security of space (SEC2); the agricultural sector (ECO7); domestic tourism (ECO16); foreign tourism (ECO17); and sustainable sources of income (ECO19). The final model of Kermanshah's future competitiveness will be that in the first stage, if the government (administration and government structure), in the form of national, regional, and local programs, pays attention to the competitive advantages of places. Especially, in large cities, and eliminating regional inequalities and in the next stage, local government (officials, managers, and all planners as the executive department) will need to act in order to operationalize the competitiveness of the city. With the correct use of opportunities and potentials (economic, socio-cultural, environmental, and security), in the 20-year horizon, Kermanshah will be a city with national and even transnational competitiveness. Otherwise, in addition to burning opportunities and destroying the capabilities of Kermanshah, other places adjacent to Kermanshah province will gradually be involved in challenges; tensions; and economic, cultural, social, environmental, security, and other crises. [ABSTRACT FROM AUTHOR]

The mechanical properties (hardness, cohesion, and residual stresses) of arc coatings designed for operation under conditions of boundary friction and corrosive-abrasive wear are analyzed. The coatings were formed by arc spraying cored wires (CW) with different charge compositions (the content of carbon, aluminum, and boron in CW charge varied). It is shown that the hardness of the coatings increases with an increase in the carbon content in them up to 1 wt. %, and then decreased due to an increase in the content of residual austenite in their structure. The level of residual stresses of the first kind in such coatings increased by four times with an increase in the carbon content to 2 wt. %. The hardness of the coatings and the level of residual tensile stresses in them also increase with a decrease in the aluminum content in them. In this case, the cohesive strength of the coatings increased due to the implementation of aluminothermic reactions in the droplets of the CW melt during their flight and crystallization on the sprayed surfaces. However, then, with an increase in the aluminum content in the coatings of more than 2 wt. %, their cohesive strength decreased. The level of residual tensile stresses in coatings with a high content of retained austenite decreased after heat treatment (tempering) of the specimens. Sometimes, after tempering, these stresses even transformed into residual compressive stresses (in particular, under using CW C1.4Cr14Ni2). At the same time, the tempering of specimens with a predominance of ferrite in the coating structure increased the level of residual tensile stresses in them, which is due to the precipitation of finely dispersed carbides or borides. It has been shown that the addition of boron-containing components (ferrochromium-boron, chromium-boron) to the composition of the CW charge leads to a significant increase in the hardness of the coatings. Thus, an increase in the boron content in coatings from 0 to 4 wt. % leads to an increase in their hardness from 320 HV to 1060 HV. However, this is accompanied by an increase in tensile residual stresses in the coatings and a decrease in their cohesive strength. [ABSTRACT FROM AUTHOR]

The quality, wear and safety of metal structures can be controlled effectively, provided that surface defects, which occur on metal structures, are detected at the right time. Over the past 10 years, researchers have proposed a number of neural network architectures that have shown high efficiency in various areas, including image classification, segmentation and recognition. However, choosing the best architecture for this particular task is often problematic. In order to compare various techniques for detecting defects such as "scratch abrasion", we created and investigated U-Net-like architectures with encoders such as ResNet, SEResNet, SEResNeXt, DenseNet, InceptionV3, Inception-ResNetV2, MobileNet and EfficientNet. The relationship between training validation metrics and final segmentation test metrics was investigated. The correlation between the loss function, the D S C , I o U , R e c a l l , P r e c i s i o n and F 1 validation metrics and D S C test metrics was calculated. Recognition accuracy was analyzed as affected by the optimizer during neural network training. In the context of this problem, neural networks trained using the stochastic gradient descent optimizer with Nesterov momentum were found to have the best generalizing properties. To select the best model during its training on the basis of the validation metrics, the main test metrics of recognition quality (Dice similarity coefficient) were analyzed depending on the validation metrics. The ResNet and DenseNet models were found to achieve the best generalizing properties for our task. The highest recognition accuracy was attained using the U-Net model with a ResNet152 backbone. The results obtained on the test dataset were D S C = 0.9304 and I o U = 0.9122 . [ABSTRACT FROM AUTHOR]

The coatings proposed are WC-based (WC-FeCrAl, WC-WB-Co, and WC-NiMoCrFeCo), alloy-based (Co-MoCrSi) or nanoWC coating-based (nanoWC-CoCr). Improving the reliability of transport vehicles requires ensuring their durability while reducing metal consumption. The development of new methods for statistically evaluating the cyclic strength of metallic vehicle parts is also significant. [Extracted from the article]

Reliability and maintenance analysis of transport machines hydraulic drives, basically focused to power units: pumps, cylinders etc., without taking in to account junction elements. Therefore, this paper proposes a research analysis on high-pressure hoses and junctions during technical maintenance. Comparative analysis of fluid behavior and energy efficiency inside non-repaired and repaired high-pressure hoses is presented in this research. Theoretical and experimental research results for hydraulic processes inside high-pressure hose is based on the numerical simulations using Navier–Stokes equations and experimental measurement of fluid flow pressure inside high-pressure hoses. Research of fluid flow dynamics in the hydraulic system was made with main assumptions: system flow rate in the range from 5 to 100 l/min, diameter of the hoses and repairing fitting are 3/8". The pressure drops, power losses, flow coefficients at non-repaired and after maintenance hose was obtained as a result. Simulation results were verified by running physical experiments to measure the pressure losses. [ABSTRACT FROM AUTHOR]

Nowadays, companies are able to obtain the key to success in global competition by choosing the right suppliers who are more align with their strategies. It is clear that applying appropriate attitudes and criteria have a great importance in choosing suppliers in the process of decision-making by chain managers and especially purchasing managers. In this study tried to apply Lean, Agile, Resilient and Green (L.A.R.G.) approach in a model designed to select the consistence supplier. Accordingly, at first, while reviewing and exploiting the literature, the most main logistics needs of the company concerned in the light of the objectives that followed on the fields of the LARG attitudes, are refined and selected, then their degree of significance is determined through Multi-Objective Performance Analysis (M.O.P.A.). The house of quality (H.O.Q.) matrix is applied to determine the importance degree of the technical characteristics of the suppliers and Taguchi loss function is applied to determine the degree of their performance deviation from the target value in each one of the technical characteristics (ultimate judgment about their competency). The considered suppliers are ranked based on the results of the loss function analysis. A sensitivity analysis was conducted to analyse the impact of different conditions on suppliers' ranking and validation of the ranking results were Satisfied by applying the T.O.P.S.I.S. method. [ABSTRACT FROM AUTHOR]

The article presents theoretical research of a transmission system that allows examination of the dynamic processes evaluating different sizes of defects in gear tooth (0%, 20%, 50%, 80% of teeth width) and gaps between the connection of the gear teeth. The dynamics of the transmission is described using the finite element method and discreet elements. This paper presents and analyzes the results of mathematical experiments on this system. [ABSTRACT FROM AUTHOR]

An automated method for analyzing the shape and size of dimples of ductile tearing formed during static and impact fracture of titanium alloys VT23 and VT23M is proposed. The method is based on the analysis of the image topology. The method contains the operations of smoothing the initial fractographic image; its convolution with a filter to identify the topological ridges; thresholding with subsequent skeletonization to identify boundaries between dimples; clustering to isolate the connected areas that represent the sought objects-dimples. For each dimple, the following quantitative characteristics were calculated: area, coefficient of roundness and visual depth in units of image intensity. The surface of ductile tearing was studied by analyzing the peculiarities of parameter distribution of the found dimples. The proposed method is applied to fractograms of fracture surfaces of titanium alloys VT23 and VT23M. [ABSTRACT FROM AUTHOR]

The improvement of transportation systems and technologic equipment leads to changing technical capabilities of this equipment. With the development of technologies, industrial development is also inevitable, resulting in correspondingly increasing need of transportation of HeavyWeight and OverSize (HW/OS) cargo. The application of a systematic approach in HW/OS cargo transportation processes allows reducing costs of delivery of such a cargo several times, which leads to a dramatic change of economic development and investment attraction conditions. Thus creating a system of criteria for the selection and assessment of HW/OS routes, which would allow selecting the most appropriate route of transportation in terms of cost and time, is expedient for this reason. The algorithm for the assessment of HW/OS cargo transportation routes will be drawn up in this article. This algorithm enables an objective evaluation of HW/OS transportation processes comparing different modes of transport, route segments, cargo transportation and cargo handling technology, and it can be practically applied to any territory. [ABSTRACT FROM PUBLISHER]

The rationalization of logistics activities and processes is very important in the business and efficiency of every company. In this respect, transportation as a subsystem of logistics, whether internal or external, is potentially a huge area for achieving significant savings. In this paper, the emphasis is placed upon the internal transport logistics of a paper manufacturing company. It is necessary to rationalize the movement of vehicles in the company's internal transport, that is, for the majority of the transport to be transferred to rail transport, because the company already has an industrial track installed in its premises. To do this, it is necessary to purchase at least two used wagons. The problem is formulated as a multi-criteria decision model with eight criteria and eight alternatives. The paper presents a new approach based on a combination of the Simple Additive Weighting (SAW) method and rough numbers, which is used for ranking the potential solutions and selecting the most suitable one. The rough Best-Worst Method (BWM) was used to determine the weight values of the criteria. The results obtained using a combination of these two methods in their rough form were verified by means of a sensitivity analysis consisting of a change in the weight criteria and comparison with the following methods in their conventional and rough forms: the Analytic Hierarchy Process (AHP), Technique for Ordering Preference by Similarity to Ideal Solution (TOPSIS) and MultiAttributive Border Approximation area Comparison (MABAC). The results show very high stability of the model and ranks that are the same or similar in different scenarios. [ABSTRACT FROM AUTHOR]

More and more recycled asphalt mixtures with high reclaimed asphalt pavement (RAP) content are used in road pavement. Having determined and evaluated RAP composition (aged bitumen content and aggregate gradation) and properties, a suitable recycling agent and virgin materials are selected in the design process. The gradation of hot mix asphalt (HMA) mixture that is recycled in an asphalt mixing plant (AMP) shall correspond to its optimal gradation set out in its job-mix formula (JMF). When RAP is recycled in an AMP, inevitable systematic and random errors of performed technological operations and inhomogeneity of virgin materials and RAP have a significant influence. These factors influence the variation of components quantities of recycled hot mix asphalt (RHMA) mixture and deviations from JMF. In this study, the principles of asphalt pavement hot recycling are systematized, which allows analysis of the factors of components' interaction influencing the results of the recycling process. The paper also presents and analyses asphalt recycling technologies in AMP and their comparative analysis. During the season of asphalt mixture production in 2014, statistical parameters were calculated according to the data obtained from one of the companies, which collected and systematized RAP batch masses, when before batching it was pre-dried and pre-heated in an additional dryer. These parameters of batch mass and RAP content in RHMA position and variation were used when evaluating the accuracy and precision of the recycling process in AMP. The obtained data showed that when RHMA mixtures are produced in a modern batch-type AMP, RAP is batched accurately, but not precisely enough. [ABSTRACT FROM AUTHOR]

This paper provides a conceptual architecture for a cloud based platform design, that implements continuously data storage and analysis services for large maritime ships, with the purpose to provide valuable insights for maritime transportation business. We do this by first identifying the need on the shipping market for such kind of systems and also the significance and impact of different factors related to shipping business processes. The architecture presented throughout this paper will be defined around some of the most currently used ICT technologies, like Amazon Cloud Services, Sql Server Databases, .NET Platform, Matlab 2016 or JavaScript visualization libraries. The proposed system makes possible for a maritime company to gain more knowledge for optimizing the efficiency of its operations, to increase its financial benefits and its competitive advantage. The platform architecture was designed to make possible the storage and manipulation of very large datasets, also allowing the possibility of using different data mining techniques for inferring knowledge or to validate already existent models. Ultimately, the developed methodology and the presented outcomes demonstrate a vast potential of creating better technological management systems for the shipping industry, starting from the challenges but also from the huge opportunities this sector can offer. [ABSTRACT FROM AUTHOR]

With the ageing transportation infrastructure, many transportation agencies across the world are focusing on rehabilitating and improving existing pavements. This means more roadwork on pavements open to vehicular traffic. Considering the rapid increase in both traffic volume and intensity in recent years, the work conditions on pavements have become difficult. Thus, there is an important need to design and construct long-lasting pavements that possess high durability, appropriate roughness or smoothness, and that which helps achieve greater time interval between repairs. The use of basalt fibers has shown to improve the durability and mechanical properties of concrete and asphalt mixtures through dispersed reinforcement. This paper presents new data and insights on the use of basalt fibers in concrete and asphalt mixtures acquired from theoretical and experimental research studies that can be useful in the design, construction and rehabilitation of highway pavements and airdrome runways. [ABSTRACT FROM AUTHOR]

Damage by pitting corrosion of the surface areas of the local oil and gas pipelines was identified and numerically analysed in this paper. Having used the methods of optical and scanning electron microscopy, the basic laws of structural and mechanical degradation were established. Based on the data of fractographic control, the shape of defects and substantiated morphological characteristics were examined. It was established that certain informative signs of the defects correspond to certain stages of operation. Having used methods of fractodiagnostics, the main reasons for the performance defects of main oil and gas pipelines were established, and the mechanisms of degradation as well as fracture of the materials they are made from were described. According to the findings, the cause of the decrease in the reliability of the main oil and gas pipeline networks is general and localised corrosion as well as technological defects in the pipeline metal. These studies are essential for the establishment of the complex of mechanical and corrosion-mechanical properties, particularly sensitive to degradation in the steel used for the pipe wall after a lengthy use of a pipe. [ABSTRACT FROM PUBLISHER]

The majority of modern gas pipelines in Ukraine, Lithuania and Russia have been operating for more than 30–40 years. The problem of forecasting residual life-time of materials comprising such gas pipelines calls for study of their degradation kinetics as well as requires to determine its relationship with the strain-force loading parameters. The aim of the paper is to study the kinetics of fracture in order to range mechanisms of cyclic deformation of 17Mn1Si steel at nucleation and growth of a fatigue crack. Flat specimens were cut out from a fragment of 17Mn1Si steel pipe after 40 years of service. Microstructures of specimens were examined. In the paper, an attempt was made to apply the combined approach to study of deformation and fracture based on the following research parameters from nonlinear fracture mechanics: physical mesomechanics and numerical fractography. [ABSTRACT FROM PUBLISHER]

The effect of the in-service scattered damage in the pipe wall metal is evaluated, and the effect of hydrogen absorbed by metal on the variation of the structure and mechanical properties of the main gas pipeline after a long-term operation is found. The main regularities in the graded nature of the static deformation process and the effect of hydrogenation on the scattered damage and fracture accumulation are found. [ABSTRACT FROM AUTHOR]

As known in transport engineering, civil engineering, transport planning and mathematics, traffic flow is the study of interactions between vehicles, drivers and infrastructure (including highways, signage and traffic control devices), with the aim of understanding and developing an optimal road network with efficient movement of traffic and minimal traffic congestion problems. The presented paper discusses a small part of a traffic flow study – the development of the methodology for assessing the speed and acceleration of a car during the column movement followingthe-leader, based on a new mathematical method. Two methods – (1) the numerical calculation of the first derivative, i.e. speed of the car movement; (2) the numerical calculation of the second derivative, i.e. acceleration of the car movement – were developed, using the fast spline transformation. In the future, parameters obtained with the help of two new methods, can be used to solve complex transportation problems, such as: (1) control of traffic flows; (2) organisation of harmonised work of traffic lights; (3) analysis of psycho-physiological condition of a driver, etc. [ABSTRACT FROM AUTHOR]

The paper presents the methodology for expert investigation of traffic accidents involving running over pedestrians. This methodology is aimed at determining the availability of any technical possibility for a motor vehicle driver, driving at a particular speed, to avoid hitting the pedestrian in a particular situation. Furthermore, the paper presents the analysis of different investigation methods and the description of investigation procedures. Various patterns of the path of the motor vehicle and the pedestrian travel before the accident are described, providing a deeper insight into the peculiarities of investigation of each particular pattern. The description is supported by the case study, illustrating the investigation of a specific traffic accident, involving actual hitting of a pedestrian. The methodology presented may be successfully used for investigating traffic accidents by experts. [ABSTRACT FROM AUTHOR]