ایمنی

In urban streets, severe traffic crashes mostly relate to vulnerable users such as pedestrians, and cyclists. Because of not being protected like vehicles for their occupants, the severity of such crashes is high. Now, in the world sustainable transportation (walking and bicycle) is highlighted, thus it is important to regard the safety of this group of users more. For this purpose, it is necessary to gain an insight from previous crashes of vulnerable users. Therefore it is possible to propose countermeasures to reduce the crashes and prevent future incidents. In this paper, association rules s used as a machine learning method to find the frequent patterns and rules in the crashes of pedestrians, and cyclists. Tehran (capital of Iran) as a city with high frequency of fatal crashes in the period of 2020 to 2021 is selected as the case study. The results indicated that most fatal crashes among vulnerable road users relate to pedestrians and motorcycles (43 and 42 percent). Most of those who died in pedestrian crashes were foreigners, homeless, and municipal workers (support 0.926). Most of the injuries related to the crash of vehicles with motorcycles (support 0.661). In injury crashes of motorcycles, road and environment factors did not have a great role. Nevertheless, human factor in the form of non-necessary agility and acceleration was an effective variable (support 0.661). Engineering, education, regulation and enforcement can be the most effective countermeasures to reduce the severe crashes among vulnerable road users in Tehran.

Road safety has long been a major social concern for people and officials, and numerous treatments (or interventions) have been implemented to improve road safety. In general, road safety remedies can be policies, legislation and enforcement, physical changes to roads or networks, and other public-purpose measures that directly or indirectly affect traffic conditions, driving behaviors, and the travel environment. In recent years, researchers and decision makers have paid a lot of attention to drivers affecting the safety of transportation routes as a treatment, and in this research, the identification and prioritization of the drivers affecting the safety of transportation routes in the geographical area of Yazd province were investigated and analyzed. This research is practical from the point of view of the goal, and from the point of view of the control of the variables and the method of data collection, it is analytical-descriptive of the survey type. Data collection in this research is a combination of library and field methods, and a large amount of information was obtained using a questionnaire. The statistical community of this research is made up of experts and specialists. The data in this study were tested using the SWARA Cresolin, Zavadskas and Torxis method. The results show that according to the calculations in Swara's algorithm, among the main drivers, the vehicle criterion with a weight of 0.2462 is the first, the increase in road safety (roadside safety) with a weight of 0.2028 is in the second place, and the criterion of the role of supervising and governing institutions on the roads is in the third place with a weight of 0.2028. , the criterion of road geometric plan with a weight of 0.1813 is in the fourth place and finally the criterion of self-representation and expressiveness of the road is in the fifth place with a weight of 0.1674.

Rail transport industry an handle a large amount of products, goods or passengers during a wide, scattered and diverse geography, which is accessible and penetrated by intruders and attackers and is also vulnerable to all kinds of physical and cyber attacks; move Therefore, it is not possible to strengthen and improve the level of security in this vast network against various types of attacks and intrusions, and it faces many obstacles and challenges. In this study, an attempt has been made to investigate the position and strategic importance of cross-border railways for the transportation of goods and passengers in the United States and investigate an unclassified set of seemingly simple attacks that have had destructive and complex effects on the traffic of the railway network and the health of citizens in the United States. be paid Also, the range of security measures of the rail transport industry and the American government, as well as the decision-makers and active activists in this field, were analyzed to reduce the risk factor and manage the crisis in complex, ambiguous and uncertain situations and when there are intrusions and structured attacks on the rail network of this country. take In this case study, the consequences of some successful attacks as well as the weaknesses and shortcomings of the American government system to ensure the security and safety of the rail transportation network in the implementation of programs and protective measures

It is one of the main priorities of safety researchers to reduce the severity of crashes by predicting the severity of crash damage. Large trucks pose safety concerns and are responsible for a high percentage of fatal crashes, so studying their crashes can help determine factors that contribute to crash severity. This study examines factors affecting the severity of large truck crashes in California using the Highway Safety Information System (HSIS). Driver, road, crashes, and vehicle characteristics were categorized as predictive variables. In this study, binary logistic regression (BLR) is used to model the level of severity of accidents and evaluate the weight of various predicting variables on the severity of injuries. Typically, various classical econometric methods are used to model the severity of accidents. Following is a discussion of how the modeling can be evaluated and optimized. Based on the modeling results of this research, the first three variables that are more important than other variables include: weather in clear conditions compared to the weather in other cases such as snowy conditions (with an exponential coefficient of 1.146), AADT in two cases more than 250,000 vehicles per day (with an exponential coefficient of 1.341) and between 100,000 and 250,000 vehicles per day (with an exponential coefficient of 1.202) are less than 100,000 vehicles per day compared to AADT (all three mentioned variables were statistically significant and had positive regression coefficients). Despite the overfitting caused by binary logistic regression, this model performs well on the data set of this study (the difference between accuracy of test and training data is 0.1%).

Construction workshops are among high-risk centers in Iran in terms of occupational accidents. The first step to control occupational accidents in this field is to raise the level of safety culture among people working in these workshops .Determining the factors affecting the safety culture and finding its relationship with the safety performance of people working in construction projects can be helpful in achieving this goal. In this research, the Dimetal Fuzzy method has been used to investigate the relationship between the factors affecting safety culture and the safety performance of people working in construction projects. The upcoming research has been conducted in an expert-centered way. In this regard, 84 experts who had work experience related to safety and were familiar with safety culture were selected in a targeted way. In the next step, 8 criteria were extracted and approved by Selected experts in this industry through a questionnaire. Finally, the relationship between the criteria and the impact and effectiveness of each was investigated using the fuzzy Dimetal method. The results obtained from the research shows that among the examined criteria, the attitude towards safety has the most relationship with other factors.Also, attitude to safety, management policy, knowledge and skills and equipment, respectively, have the most influence and communication, Personality, safety training and continuous supervision have the most impressione.

Many individuals have been affected physically and socially as a result of road crashes. Many of these incidents have irreversible consequences. An immediate solution to improve road safety must be developed. This paper examines the issue of inadequate budget allocations by road departments for road safety. With a budget that does not meet ideal requirements, maintaining an extensive road network poses a challenge. This paper proposes an economic model for improving rural road safety, considering its importance. To minimize costs and reduce road casualties, the proposed model takes into account a number of factors, including the geometric conditions of the roads, relevant information, and the economic conditions of the community. In order to improve road safety, the study employs an integer programming model. In this approach, road geometry, relevant data, and economic considerations are examined in order to implement appropriate safety solutions. This paper discusses safety improvement strategies based on calculated probabilities of implementing them. These probabilities are determined using the Naive Bayes method. In addition to the geometric aspects of the roads, the best method for improving road safety is also considered in the economic model. Validation of the model is based on a case study conducted in Kerman province. The unique characteristics of each rural road in a country can be considered when implementing safety measures. The proposed method is used to accomplish this. As a result of the results, four safety solutions were identified as the most suitable in the Anar-Rafsanjan area, including road lighting, vibrating grooves, guardrails, and repairing damage and unevenness.

Estimating the safety and comfort of the occupants of a road-using vehicle is one of the most important issues facing researchers in the field of road and road safety. Road safety is examined in different branches. One of the most important parts of road safety assessment and maintenance management is the assessment and monitoring of road surface failures. The Road Roughness Index (IRI) is used for this purpose. . In order to evaluate the path of the road, in addition to evaluating the geometric design, it is also necessary to evaluate the geometry of the faults. If a criterion can be found to assess the situation, the critical state of the criterion can be found and if it reaches a critical state, the road condition can be considered unsafe or in need of improvement. In this research, the dynamic response of the vehicle while moving on roads with different rough shapes but with the same IRI (the case where the two-wheel IRI of the vehicle is equal to 10) is simulated by the software. In addition to examining the dynamic response of the front axle of the vehicle (due to the application of more force on the front axle) on common parameters such as: vertical acceleration, maximum vertical acceleration and the minimum root of vertical acceleration, to determine whether in a symmetrical roughness, again a response Is there dynamics for the left and right wheels? If a clear relationship can be established between the roughness created by the definition of the IRI index at the road surface and the shape of the roughness (wavelength and amplitude), it is possible to prioritize the breakdowns with critical wavelengths (most inconvenient). The results show that by further examination of the vertical acceleration at different speeds, it can be seen that in the amplitude of longer waves, the highest values ​​of vertical acceleration entered by the vehicle at speed. High speeds occur and also maximum vertical acceleration values ​​occur at lower wavelengths at lower speeds. For example, in parabolic failure, the maximum acceleration values ​​for the wave amplitudes of 0.1(m), 0.05(m), 0.01(m), 0.005(m) occur at speeds above 60 km / h. Vertical acceleration values ​​for wave amplitudes of 0.0025, 0.0015 and 0.001 occur at speeds of less than 40 km / h. At a speed of nearly 80 km / h, the value of the vertical acceleration of sinusoidal roughness (according to IRI) shows a significant difference of about 0.2 m / s relative to the parabolic.

Interlocking as a heart of railway signaling system is an important part of this safety-critical system. Looking at the interlocking tasks including correct routing, locking the routes and releasing them timely and commanding to wayside equipment, including signals, point machines and track circuits, will be revealed due to the critical nature of these tasks, interlocking necessarily must have a high tolerance against different probable faults. The best way to design a fault tolerant system is redundancy in processors. Structures with 2 processor units (dual hot stand-by), 3 processor units (3-vote-2 redundancy) and 4 processor units (double 2-vote-2 redundancy) are the most practical techniques which manufacturers have used in the interlocking systems. These redundancies improve reliability, safety and fault tolerancy of system. Each structure has its own advantage. In the Markov method by considering the different states of processors and failure rate, system state diagram is obtained. Then the system transitions between the various operating modes can be expressed by a matrix. The state transition equations formed the behavior of the system to fully assess the safety, reliability and mean time to failure of interlocking system to quantify these indexes. In this article we evaluate and compare the reliability and safety of mentioned structures and study the impact of system parameters (such as failure rate and coverage factor) on the dependability property. We showed that the increasing of coverage factor can straightly improve the safety and also reliability of the system, in addition the control strategy of switch in the hardware of redundant interlocking system is very important in the dependability of this system.

Because of its convenience and low cost, rail transportation has become one of the most attractive modes of transportation for passengers and business owners alike. Rail transportation has been reduced in popularity due to accidents. This study investigates the factors that affect the severity of accidents for freight, passenger, and other rail vehicles in three levels of death, injury, and damage. A multinomial logit model (MNL) regression was used to model the Iranian railway accident data from 2006 to 2021. The model quantifies the effects of each variable on the severity of events by quantifying the results. The results of this study indicate that type of accidents (with pedestrians), type of accidents (with road vehicles), speed exceeding the allowable speed (equal to or exceeding 30 km/h), speed during the accident (equal to or exceeding 30 km/h), multilane rails and moderate variables are among the variables that have a greater impact on the severity of accidents than other variables, so investing in these areas improves rail safety. Because of budget constraints, this research work will be effective in attracting the attention of policy makers and transportation managers in this area.

In many countries, the main priority of traffic safety is to implement measures that reduce operational speed and increase compliance with speed limits, because improper speed is recognized as the most important cause of serious traffic accidents. Traffic calming measures are engineering measures that reduce the number and severity of traffic accidents by significantly reducing the speed of vehicles, and thus improve road safety. In this study, 28 flat and arcuate speed humps of Mahmudabad to Chalous axis with a length of approximately 80 km due to high density of residential areas and the growth of small communities along the main intercity road, as a representative of physical calming devices and speed display sign as a representative of perceptual calming devices were selected and modeling the speed selection of drivers in dealing with this type of traffic calmer using indicators such as speed hump height, speed hump width, speed hump entrance slope, initial speed, The difference between the initial velocity and the allowable velocity displayed on the speed display sign, in the Neural network (MLP) platform was done. The output results of the model indicate that this model was able to predict the speed selected by users by receiving the mentioned specifications.

The expansion of cities and the increase in the price of land has caused an increase in the number of underground floors and the depth of excavation, and considering that ensuring safety in excavation workshops, in addition to ensuring the health of employees, leads to an increase in the quality of the project, therefore, one of the important issues in urban construction and structures. Is to create proper stability during excavation, excavation is one of the dangerous earth operations. According to available statistics, many people lose their lives every year in excavation projects due to non-compliance with safety principles. In this research, first by conducting library studies, a list of effective risks in sustainable urban deep pit projects was prepared using the strut method, and experts' opinions were collected through a questionnaire and analyzed in SPSS software. Then the decision matrix was formed based on the desired indicators and criteria and were ranked using a questionnaire and based on the criteria of "level of influence", "level of importance" and "existence of necessary tools." Execution for wide pits", "Execution limitation in projects with irregular geometry or geometry", "Inability to use to increase the depth of the pit during execution or after the completion of excavation", "Too much settling in the pit and causing disturbance to the implementation of the foundation and structure", "the possibility of equipment and machinery colliding with the elements and putting them at risk", "collapse of walls and elements falling", "increasing the cost of implementation in deep pits and large fields compared to usual methods", "increasing Implementation time in deep pits and large fields compared to usual methods", "Falling from a height during work on connections", "need for strict quality control to implement restraints, especially connections" have the highest impact, respectively.

Today, due to its high safety factor and favorable environmental pollution, rail transportation has a major contribution to the movement of cargo and passengers. The use of modern technologies such as automatic control systems in signaling, communication, and train control increases speed. The number of rail accidents has also decreased in the field of safety. Due to the country's strategic position, which is located in the center of the north-south and east-west corridors, neighboring countries with oil and gas resources are often forced to transit their oil and gas exports through Iran's railway lines. So in order to To increase safety and prevent accidents, the transportation of dangerous goods by rail should be carried out in compliance with all safety principles, such as compliance with unloading and loading rules, the selection of wagons suitable for the conditions of transportation of dangerous goods, and the labeling of wagons. In this article, railway accidents related to trains’ escapes in the world and as a case study, the accident and explosion of freight wagons at Khayyam station are investigated, and the causes and factors of such accidents are discussed, the most important of which are: performance Inadequate and defects in the braking system of trains, improper brake adjustment during the brake test process, lack of compatibility and matching of cargo in successive wagons and replacement of the locomotive. Also, guidelines for prevention and improvement of safety have been provided.

Considering that the road factor along with the two factors of human and vehicle plays an important role in road accidents, so optimal and suitable road safety is improved through road geometric design, road surface structure (road pavement), and the installation of a variety of signs And road safety equipment will be important in reducing accidents and road accidents. Studies on the role of road accidents as the most important driving force in our country indicate that 75% of accidents occur in 20% of the total number of different paths, which, for various reasons, are included in the paths of the accident. . In other words, about 36,000 km out of a total of 180,000 km of roads in the country are affected by road accidents. In this research, the evaluation and ranking of the factors affecting road accidents in Markazi province were carried out using the equation structure (SEM) by preparing a questionnaire and a decision procedure Multidimensional Inventory (MCDM) of 80 factors involved in the ways of the central province. The results show that the index of road barrier obstructions in Friedman rank of 959/5 is of prime importance. It shows that most of the trails in this province are completely separate. The majority of crashes in the central provinces were due to lack of Enough to be seen. Direction Lighting Index 553/5 is ranked second. The construction quality index and geometric specifications and asphalt pavement are rated at 125/5 points in third place.

Airports are one of the most vital infrastructures of any country, which play an important role in transporting cargo and passengers to different parts of the world. The preservation and optimal use of airport resources and assets is one of the main goals of airport managers. On the other hand, airlines have a special concern on saving time, fuel consumption, maintaining passenger satisfaction, and so on. One of the most important resources in the world's major airports are the gates of the passenger terminals of airports, which have an undeniable aspect in the better performance of the airport. The assigning of aircraft to these gates has long been a concern for researchers in operations research as well as air transport activists. This research deals with the issue of assigning aircraft to the passenger terminal gate. The problem of optimal gate assignment is a complex issue and requires consideration of many parameters and variables in order to achieve the desired result. In this research, it’s tried to solve the gate allocation problem by presenting a suitable model. Providing an appropriate linear model is one of the main challenges of the problem. A special attention has been paid to the issue of safety. Therefore, by applying safety restrictions, a suitable model is provided. The main purpose of this study is to minimize the scatter of idle (lost) gates while not preventing mismatch between flight size and gate and also justifying safety needs. These cases are assigned and examined in the framework of the optimization model in this research. To solve such problems, which are usually not possible by manual calculations or are very time consuming, the metaheuristic algorithms are used. Since because NP-Hard nature of problem, it is very time consuming and difficult in the usual way. Therefore, this study tries to provide an efficient and fast way to solve the gate assignment problem. In the proposed method, first all the sentences of the objective function were considered as, then all were divided into two categories of hard and soft constraints. On the other hand, in the model of the basic method, the power of two terms in the objective function is used. The proposed model was modified. In the end, it was tried to modify the terms of the objective function and constraints in such a way that in addition to meeting the expectations and constraints of the problem, it allows the use of two flights from the same gate (MARS effect) to increase resource efficiency. The method is based on a genetic algorithm that includes the initial population, selection, combination or mutation, generation of a new offspring, and re-selection. In this study, 5 scenarios with various flights and gates have been used. The improvement of total idle times in the first scenario was 72.75%, in the second scenario 76.92%, in the third scenario 82.38%, in the fourth scenario 82.38% and in the fifth scenario 79.67%. All of results. Show the efficiency of proposed model.

In general, any type of accident, occupational disease, or environmental damage inflicts enormous and sometimes irreparable damage directly and indirectly on organizations. The mentioned method is an integrated system that tries to create a healthy, pleasant, lively environment away from accidents with convergence, unifying arrangement of manpower, facilities and equipment, and can be observed by observing its plans in the Health and Wellness Organization of Manpower. , Provided protection against hazards and a healthy environment in the workplace, thus reducing existing risks.Slowness and lack of progress in the implementation of construction projects leads to the lack of sustainable project management, which indicates the existence of obstacles and root problems in the implementation of valuable urban projects that seriously threaten reconstruction and development and can be considered as a crisis of construction projects. named. The main problem that most large projects face is delays in various phases and eventual completion of the project. A delay is an action or event that extends the time specified in the contract to perform a particular action. Various officials and experts must be spent in order to successfully implement such projects within the specified time frame. Because in terms of scientific status and value, according to project management characteristics and factors. Affecting the success of projects, achieving one's time goals. One of the most important indicators of success is the direct relationship between the weakness of safety culture and the increase in the rate of accidents and human, economic and environmental damage has been proven in many similar studies. In addition, in recent years, following the occurrence of numerous accidents, the emphasis has been on creating a positive safety culture, increasing the level of training received, more experiences of accidents and hazards in the workplace, as well as gaining better job positions and therefore safer. . Also, the direct relationship between education level and safety culture score has been emphasized in many studies. Organizations have experienced increasing growth.

Pedestrians in developing countries are one of the most vulnerable groups in transportation. Of the total traffic fatalities in one year in Iran (16 thousand 201 people), 20.8 percent (3 thousand 370 people) were pedestrians and 23.8 percent (3 thousand 862 people) were riding motorcycles. Therefore, the purpose of this research is to identify the factors related to pedestrian accidents and improve the safety of suburban roads. In order to achieve the desired goal, the Damavand Road in Jajrood police area before the campus entrance has been examined for pedestrian accidents. The findings showed that in total, 159 pedestrian accidents had occurred in the studied road within 5 years. After inspecting the points and making the checklists, factors such as lack of sufficient visibility of vehicles, inappropriate steps of the pedestrian bridge, lack of lighting, lack of proper safety protection next to the steps of the pedestrian bridge have been effective factors in these points. Among the proposed solutions, we can mention the improvement of the condition of the overpass in terms of safety and lighting and the creation of a curb line on the side of the road.

Large number of road crashes and their consequences has made road safety a worldwide challenge. Behind any traffic conflict indicators are assumptions which takes them away from statistical analysis of real road crashes. We conducted road crash simulation using finite element methods and analysis them to asses safety. To high accurate scrutiny crashes, finite element is used. By running crash finite element models in Ls-Dyna simulation is ran based on angles and relative velocities in different states (area stucked in crash). In other words multy body elasto-plastic dynamic finite element model is simulated. By analyzing vehicle sets before and after crash and by means of kinetic energy law, dissipated energy is calculated. Dissipated energy reveals as transformation in area stucked in crash. Therefore for each crash scenario dissipated crash energy is calculated and graph for each one is derived. Different mode of material is assessed and reflected in crash analysis. So by energy absorbtion crash severity is predicted.

Urban road traffic calming measures, as an effective factor in increasing the level of safety of pedestrians and cyclists, limiting the speed of motor vehicles, and reducing casualties due to accidents. The present article analyzes and interprets Persian-language scientific-research articles in the period 2008-2020 by conducting a systematic review. The results showed that the application of accelerators and speed bumps on urban roads as a cross-sectional physical solution had a significant effect on reducing the speed of vehicles. In this regard, the comparison between the types of accelerators and speed bumps and control of their proper installation location can be evaluated in more detail in future studies. The results also showed that the change in pavement level a non-physical solution to reduce the speed to the allowable range is not very effective and needs to be combined with other solutions to achieve this, which requires new studies in this area. It should be noted that the use of simulation tools to measure the performance of the proposed solutions for combining relaxation tools can also be effective, and can be used by other researchers. Further-more, the results showed that previous studies have paid less attention to the effectiveness and analysis of the performance of relaxation devices such as deviant diagonal islands and traffic.

Accidents impose irreparable costs on the economy of countries every year. In addition, many of the death statistics are related to accidents, which can endanger the human factor itself, which is the driving factor of the economy. In the meantime, one of the road users who is very are exposed to accidents, it is the motorcycle riders who every year include a large part of the dead and injured in the accidents, the main purpose of which is to investigate the variables affecting the accidents of motorcycle riders. Collecting information on accidents as well as using various statistical and modeling methods such as Friedman, Aamili, Logit model and neural network to investigate the effect of each of these variables. The results showed that the variables of accident season, cause of accident, road surface conditions and lighting conditions had the highest rank respectively. On the other hand, the variables of the day and season of the accident and the age of motorcyclists, respectively, had the least importance in the occurrence of motorcyclist accidents on the roads of Gilan province. In addition to these variables, weather conditions, road surface conditions and lighting conditions were the first effective factors in the accidents of motorcyclists in Gilan province; According to the logit model obtained from the accidents of motorcycle riders, it was found that the variables of spring season, 6 to 12 and 18 to 24, dry surface conditions, night lighting conditions without sufficient light; rainy weather; Failure to pay attention to the front and sudden change of direction increase the possibility of accidents of motorcyclists on Gilan road crossings. based on the neural network model; The values of cause, lighting conditions and weather conditions respectively have the greatest effect on the severity of motorcyclist accidents on Gilan roads. Also, the neural network model with R2 values of 93.31 showed higher accuracy than the logit model.

Today, the metropolis of Tehran, like many metropolises in developing countries, is facing serious problems due to the ever-increasing demand for transportation and the problems of the public transportation system. One of these problems is the widespread use of motorcycles in these cities, which has caused an increase in air pollution, noise pollution and accidents. Today in our country, due to the high number of traffic accidents, the issue of safety, especially the safety of motorcycle riders, is of great importance. Therefore, this study has been conducted with the aim of identifying the factors affecting the damage or injury of motorcycle accidents in Tehran city with the help of information from accident forms filled by traffic police officers at the accident scene in May and November 2013. The double logit model was used to build models of motorcycle accidents in May and November 2013 in Tehran. The results show that factors such as the type of land use where the motorcycle accident occurred, the direction the motorcycle collided with another vehicle, the type of road and the lighting of the air have an effect on the severity of the motorcycle accident and, as a result, whether it is injured or damaged.