Deceleration of sliding motorcycles (mainly scooters) in accident reconstructions

2017 ◽  
Vol 232 (7) ◽  
pp. 866-876 ◽  
Author(s):  
Carlo Cialdai ◽  
Dario Vangi ◽  
Antonio Virga
Keyword(s):  
Urban Areas ◽  
Test Session ◽  
Road Accidents ◽  
Factors Affecting ◽  
Different Types ◽  
Energy Dissipated ◽  
Comparison Of The Results ◽  
Two Wheeler ◽  
The Impact ◽  
Good Agreement

This paper presents an analysis of the situation in which a two-wheeler (i.e. a motorcycle, where the term motorcycles includes scooters) falls over to the side and then successively slides; this typically occurs in road accidents involving this type of vehicle. Knowing the deceleration rate of the sliding phase allows the kinetic energy dissipated and the speed of the motorcycle just before the fall to the ground to be calculated. These parameters are very important in the analysis and reconstruction of accidents. The work presented in this paper was developed in two experimental test sessions on fully faired motorcycles which are mainly of the scooter type and widely used in urban areas. In the first session, sliding tests were carried out, with the speed in the range 10–50 km/h, on three different types of road surface. Analysis of the evidence allowed the dissipative main phases of motion of the motorcycle (the impact with the ground, the rebounds and the stabilized swiping) to be identified and some factors affecting the phenomenon to be studied. The coefficient of average deceleration was calculated using two typical equations. The second test session consisted of drag tests. In these tests, the motorcycle, which had previously laid on its side, was dragged for a few metres at a constant speed of about 20 km/h, while the drag force was measured. A comparison of the results obtained in these tests with those obtained in the sliding tests yielded very good agreement in the coefficients of deceleration.

Treating Afro hair loss: signs, symptoms and specialist interest

2021 ◽  
Vol 10 (5) ◽  
pp. 190-197
Author(s):  
Ingrid Wilson
Keyword(s):  
Black Women ◽  
Hair Loss ◽  
Factors Affecting ◽  
Different Types ◽  
Recent Developments ◽  
Hair Care ◽  
Care Practices ◽  
The Aesthetic ◽  
The Impact ◽  
Symptoms And Signs

This article explores the different types of hair loss that black women may experience more than other groups of patients. Properties of African hair and the impact of hair care practices are discussed, as well as factors affecting the presentation of other hair loss conditions. It is important for the aesthetic practitioner to be able to distinguish between the temporary forms of hair loss that they can help to treat and the permanent or scarring forms of hair loss, which need a prompt referral to a dermatologist with a specialist interest in hair. Prompt recognition and referral can help to delay the progression of hair loss. The symptoms and signs that patients and practitioners should be alerted to are explored, as well as the treatments that can help and where referrals may be necessary. Recent developments and gaps in knowledge are summarised.

scholarly journals FEATURES OF ASSESSMENT OF ANTHROPOGENIC LOADS ON NATURAL COMPLEXES

2020 ◽  
Vol 2 (5) ◽  
pp. 19-24
Author(s):  
P. Evdokimov
Keyword(s):  
Urban Environment ◽  
Urban Areas ◽  
Anthropogenic Impact ◽  
Urban Environments ◽  
Anthropogenic Factors ◽  
Factors Affecting ◽  
Main Research ◽  
Regulatory Documents ◽  
Dialectical Approach ◽  
The Impact

the article describes the problems of assessing the anthropogenic impact of human activity on natural com-plexes surrounding urbanized territories. Among the main research tasks are development of methodological foundations for assessing the quanti-tative and qualitative composition at anthropogenic impact on natural complexes surrounding urban areas. The main method of this research include a dialectical approach that focuses on generally accepted logi-cal research methods (analysis, systematic approach, generalization) and their synthesis using relevant in-formation materials. The author considered various methods of assessing the impact of various factors on the environment, and also carried out the examination of urban decisions related to the appointment of a category (status) the natural resources included in the urban environment in Moscow. The Russian capital is a European metropolis, the largest city-millionaire in Europe and a typical object of research to identify the effects of various anthropogenic factors. The implementation at economic activity in the metropolis is accompanied by the emergence of problems, the solution of which has not been found yet. Analysis of methods for assessing the impact at the various factors on the environment was carried out taking into account the provisions in regulatory documents governing the appointment for protected areas urban environment. Provisions of regulatory documents and decisions of executive authorities designed to use natural (forest) resources in urban environments. The absence of approved methods for assessing certain types of land plots with a protected status was identified. The main factors affecting the quality of biogeocenosis were identified. The main features of the applica-tion methods for assessing the status and possibility in recreational development in territories of varying de-grees at development are considered.

Effect of Rainfall Intensity and Road Crossfall on Skid Resistance of Asphalt Pavement

2014 ◽  
Vol 70 (4) ◽  
Author(s):  
Haryati Yaacob ◽  
Mohd Rosli Hainin ◽  
Sudesh Nair A/L Baskara
Keyword(s):  
Weather Condition ◽  
Water Film ◽  
Road Accidents ◽  
Factors Affecting ◽  
The Road ◽  
Pendulum Test ◽  
Different Types ◽  
Sand Patch ◽  
Wet Weather ◽  
Major Factors

Skidding is one of the major factors to road accidents during wet weather condition. Skidding during wet weather happens when water film presents between the tyre and pavement reducing the friction of tyre onto the road surface. This laboratory study was carried out to investigate the factors affecting Pendulum Test Value on Asphaltic Concrete surfaces. The main objective of this study is to determine the pavement type and the crossfall percentage that best resist skid during wet weather condition. Three different types of dense graded mixes were used in this study which are AC10, AC14 and AC20. Those three constructed mixes were tested using Sand Patch Test (SPT) and were then subjected to various rainfall conditions and crossfall percentages using Rainfall Simulator. The rainfall conditions are categorized as low rainfall, medium rainfall and high rainfall while the crossfalls were increased 2% from 0% to 10% crossfalls. During the event of rainfall on each pavement surfaces, a British Pendulum Tester (BPT) was used on the pavements to obtain the Pendulum Test Value (PTV) at different crossfalls. Collected data are analyzed using analysis of variance (ANOVA) to justify the objectives. Results from PTV shows that 4% to 10% crossfall is the best crossfall and AC20 is the best surface type in resisting skid.

The effects of conflict on risk perception and travelling intention of young tourists

2015 ◽  
Vol 10 (1) ◽  
pp. 118-130 ◽  
Author(s):  
Helena Desivilya ◽  
Sharon Teitler-Regev ◽  
Shosh Shahrabani
Keyword(s):  
Design Methodology ◽  
Priming Effect ◽  
Risk Estimation ◽  
Content Type ◽  
Factors Affecting ◽  
Conflict Area ◽  
Different Types ◽  
Travel Abroad ◽  
The Impact ◽  
Structured Questionnaire

Purpose – The purpose of this paper is to compare the evaluations of various risks by young Israelis living in conflict area and their Polish counterparts, who do not live in conflict area and how these perceptions affect their traveling intentions to destinations with different types of risks – Egypt, Turkey, India and Japan. Design/methodology/approach – The research participants were 713 Israeli and Polish students who responded to a structured questionnaire. Findings – The findings validate the assumption that contextual distinctions shape differently factors affecting traveling risk estimation and the intention of young people to travel abroad. The results indicated that the priming effect is substantial, reflected in Israelis’ significantly higher assessments of risks concerning destinations with terror, health and natural disasters hazards in comparison to Poles’ evaluations. As predicted, Israeli students exhibit lesser intentions to travel to Turkey, Egypt and India than their Polish counterparts. The study also showed similarities between Israeli and Polish students. Young tourists’ with strong aversion to health hazards exhibit low intention to travel to India and those refraining from economic crisis are reluctant to travel to Egypt. The intention to travel to Japan and India decreased with high perception of destination risks. Originality/value – The current study constitutes a new departure in studying the contextual effects on travel-related decision making. It focusses on the impact of conflict ridden environment on intentions, attitudes and risks perception of young tourists with respect to traveling to risky destinations, previously hardly studied.

scholarly journals Effects of Driving Style and Vehicle Maintenance on Vehicle Roadworthiness

2020 ◽  
Vol 32 (5) ◽  
pp. 667-677
Author(s):  
Iva Mikulić ◽  
Igor Bošković ◽  
Goran Zovak
Keyword(s):  
Environmental Sustainability ◽  
Traffic Accidents ◽  
Aggressive Driving ◽  
Driving Style ◽  
Factors Affecting ◽  
Technical Inspection ◽  
Road Users ◽  
Different Types ◽  
The Impact ◽  
The Relationship

Vehicles that are non-roadworthy pose a hazard for all road users and can be one of the main causes of traffic accidents. Previous studies have analysed the impact of the driving style on environmental sustainability and road safety. Starting from this, there was a need to further investigate the relationship between the driving style and vehicle roadworthiness as well. Vehicles that do not comply with the prescribed requirements should be excluded from traffic at a periodic technical inspection. However, the causes of detected vehicle defects cannot be established at a periodic technical inspection. The paper therefore, examines the factors affecting vehicle roadworthiness. First, the failure rate and mileage of vehicles at periodic technical inspection regarding the type of ownership was examined. In addition, a questionnaire was conducted to collect data about the driving style and maintenance habits of different types of car owners. The paper argues that vehicles owned by legal entities were generally in a worse condition than the vehicles owned by natural persons, due to the increased vehicle exploitation, but also due to a more aggressive driving style. Finally, it was found that by modifying their driving style, the drivers can affect the condition of their vehicles, considering the same mileage and maintenance habits.

scholarly journals Brain Drain: Comparative Study of Propulsive Factors

sjesr ◽  
2021 ◽  
Vol 4 (1) ◽  
pp. 324-331
Author(s):  
Sumera Shabnum ◽  
Nadeem Iqbal ◽  
Haseebullah Khan
Keyword(s):  
Human Capital ◽  
Environmental Factors ◽  
Brain Drain ◽  
Random Sampling ◽  
Urban Areas ◽  
Factors Affecting ◽  
Demographic Transitions ◽  
Probit Models ◽  
The Impact ◽  
Populous Country

Brain drain is one of the important aspects of development economics/Demographic transitions. A populous country has the potential to export human capital. There are so many determinants of Human Capital Outflow (HCO). Some like economic, social, and political drivers are already discussed in the previous studies. This study compares the impact of various classes of variables on the HCO. Furthermore, it gives recommendations for controlling HCO based on such results. Data is collected in the form of questionnaires from three rural and three urban areas of Peshawar. Random sampling is used. Probit models are used for comparing the significance of variables. The study shows that not only the classic variables, i.e. economic, social and political are important but also the newly introduced religious and environmental factors have a great impact on HCO. The forthcoming researchers can do further study by considering even more factors affecting the HCO. They can conduct studies for different areas and on different scales.

scholarly journals Energy dissipation of a particle colliding on a flat surface

2021 ◽  
Vol 249 ◽  
pp. 06007
Author(s):  
Fabricio Éric Fernández ◽  
Marcelo Fabián Piva ◽  
Román Gustavo Martino ◽  
María Alejandra Aguirre
Keyword(s):  
Kinetic Energy ◽  
Degrees Of Freedom ◽  
Flat Surface ◽  
Coefficient Of Restitution ◽  
Normal Direction ◽  
Normal Velocity ◽  
Factors Affecting ◽  
Different Types ◽  
Before And After ◽  
The Impact

To gain an understanding of the factors affecting the interaction of one grain with its environment as it reaches equilibrium, we study a particle bouncing off a flat surface. The bouncing of the particle leads to dissipation that is usually characterized with t, the coefficient of restitution, defined as the ratio between the velocity component that is normal to the contact surface just before impact (Vn) and the same component, but immediately after the collision (Vn’), i.e. related to a kinetic energy corresponding to motion in the normal direction. We will show how d is affected by energy stored in other degrees of freedom and transferred to kinetic energy that leads to an increase in normal velocity after the impact Vn’, and therefore to, ɛ >1. For this purpose, the evolution of potential, translational kinetic energy and rotational kinetic energy is analysed during the whole relaxation process and just before and after each collision for two different types of particle, a disk and a faceted particle.

ASSESSING THE ADEQUACY OF MODELING THE IMPACT OF HEAVY CHARGED PARTICLES ON A CHIP

2016 ◽  
Vol 8 (4) ◽  
pp. 10-12 ◽  
Author(s):  
Грошев ◽  
A. Groshev ◽  
Чубур ◽  
K. Chubur ◽  
Яньков ◽  
...  
Keyword(s):  
Charged Particles ◽  
Heavy Charged Particles ◽  
Comparison Of The Results ◽  
The Impact ◽  
Theoretical Results ◽  
Good Agreement

Considered a comparison of experimental and theoretical results is the number of failures at the chip under the influence of heavy charged particles. Comparison of the results showed good agreement.

scholarly journals Index Decomposition Analysis on Factors Affecting Energy-Related Carbon Dioxide Emissions from Residential Consumption in Beijing

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Fengyan Fan ◽  
Yalin Lei
Keyword(s):  
Rural Areas ◽  
Urban Areas ◽  
Carbon Dioxide Emissions ◽  
Decomposition Analysis ◽  
Impact Factors ◽  
Energy Structure ◽  
Factors Affecting ◽  
Index Decomposition ◽  
Urban And Rural Areas ◽  
The Impact

Beijing’s residential CO2emissions have become the main growth point of CO2emissions. However, the impact factors of the direct energy-related CO2emissions from residents in Beijing have not been previously evaluated. This paper accessed the key factors that affect the residents’ CO2emissions in Beijing from 1995 to 2015, using a newly built decomposition model with generalized Fisher index (GFI) and M-P model. The results were compared between urban and rural areas. Urban residential CO2emissions did not change during 1995–1999 but then grew rapidly after 1999, while rural residential CO2emissions fluctuated during the studied period. Increased per capita income is the most important pulling factor for the growth of residential CO2emissions, while energy consumption intensity is a decisive factor in inhibiting residential CO2emissions. Population size plays a pulling role in the growth of residential CO2emissions. Energy structure exerts a role in inhibiting residential CO2emissions, and its inhibition effect is stronger for urban residents. Average consumption propensity inhibits urban residential CO2emissions but has little effect on rural residential CO2emissions. The population migration from rural to urban areas in the urbanization process increases residential CO2emissions. To reduce residential CO2emissions, several recommendations have been proposed.

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