A Method to Evaluate Vehicle Impact Speeds in Passenger Car-Pedestrian Accidents

2016 ◽  
Vol 835 ◽  
pp. 788-792
Author(s):  
Cheng Jian Feng ◽  
Kui Li ◽  
Zhi Yong Yin
Keyword(s):  
Traffic Accidents ◽  
Linear Regression Analysis ◽  
Average Height ◽  
Passenger Car ◽  
Impact Speed ◽  
Pedestrian Injury ◽  
Vehicle Impact ◽  
Pedestrian Crashes ◽  
The Impact ◽  
The Relationship

This paper aimed to research the relationship between the wrap around distance (WAD) to head contact and vehicle impact speed based on real pedestrian traffic accidents with video. A team was established to collect passenger car-pedestrian accident cases occurring between July 2011 and July 2015 in Chongqing, China. A total of 15 pedestrian crashes were selected into the sample. Impact speeds were calculated by a video analysis technology, and the WAD was revised according to the average height of pedestrians involved in the sample. The relationship between the WAD and impact speed was analyzed using linear regression analysis. We propose a method to evaluate the impact speed in passenger car-pedestrian. These results will contribute to the development of judicial identification and research of pedestrian injury.

The Impact of Adopting CSR on the Firm's Overall Performance

2021 ◽  
pp. 239-255
Author(s):  
Abdelmajid Ibenrissoul ◽  
Khawla Bouraqqadi ◽  
Souhaila Kammoun
Keyword(s):  
Developing Countries ◽  
Regression Analysis ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Social Dimensions ◽  
The Social ◽  
Managerial Implications ◽  
Overall Performance ◽  
The Impact ◽  
The Relationship

The purpose of the chapter is to study what effect CSR has on firms' overall performance in a developing country context. While most of the previous empirical researches focused on the relationship between CSR and financial performance, the present study suggests exploring the impact of CSR on overall performance which encompasses economic, environmental, and social dimensions as well as stakeholders. The empirical study aims to analyze and measure the social and environmental involvement of large Moroccan firms operating in the main sectors of activity and located in different geographical areas. Using multiple linear regression analysis, the authors empirically test the impact of CSR on overall performance on a sample of 44 companies. The main findings reveal that CSR is a driver for improving image and reputation, enabling the firm to achieve overall corporate performance. On the basis of the main results, they set out some managerial implications and further directions for CSR research in developing countries.

Effect of endometrial thickness on birthweight in frozen embryo transfer cycles: an analysis including 6181 singleton newborns

2019 ◽  
Vol 34 (9) ◽  
pp. 1707-1715 ◽  
Author(s):  
Jie Zhang ◽  
Hongfang Liu ◽  
Xiaoyan Mao ◽  
Qiuju Chen ◽  
JiQiang Si ◽  
...  
Keyword(s):  
Linear Regression ◽  
Embryo Transfer ◽  
Gestational Age ◽  
Endometrial Thickness ◽  
Linear Regression Analysis ◽  
Tertiary Care ◽  
Frozen Embryo Transfer ◽  
Z Scores ◽  
The Impact ◽  
The Relationship

Abstract STUDY QUESTION Does endometrial thickness (EMT) have an impact on singleton birthweight in frozen embryo transfer (FET) cycles? SUMMARY ANSWER An EMT <8 mm was associated with a lower mean birthweight and gestational age- and gender-adjusted birthweight (Z-scores) of singletons resulting from FET. WHAT IS KNOWN ALREADY Previous studies have examined the impact of EMT on IVF success rates. Little is known, however, regarding the relationship between EMT and neonatal birthweight. STUDY DESIGN, SIZE, DURATION This retrospective study involved singleton live births born to women undergoing frozen-thawed Day 3 embryo transfer during the period from January 2010 to December 2017 at a tertiary care centre. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 6181 women who fulfilled the inclusion criteria were included and were grouped into five groups depending on the EMT: <8 mm, 8–9.9 mm, 10–11.9 mm, 12–13.9 mm and ≥14 mm. EMT between 10 and 11.9 mm was taken as a reference group. Singleton birthweight was the primary outcome measure. A multivariable linear regression analysis was performed to detect a relationship between EMT and newborns' birthweight after controlling for a number of potential confounders. MAIN RESULTS AND THE ROLE OF CHANCE A modest but significant decrease in birthweight was observed in the EMT <8 mm group as compared with groups with EMT ≥10 mm, with a mean difference of 89–108 g. Also, singletons from the EMT <8 mm group (0.24 ± 1.04) had a significantly lower birthweight Z-scores than those from the EMT 10–11.9 mm (0.41 ± 1.02; P = 0.032) or EMT 12–13.9 mm (0.46 ± 1.07; P = 0.004) groups. Further, multiple linear regression analyses indicated that parental BMIs, gestational age, newborn gender, pregnancy complications and EMT <8 mm were all independent predictors of neonatal birthweight. LIMITATIONS, REASONS FOR CAUTION The present study was limited by its retrospective design. Future prospective studies are required to confirm our findings. WIDER IMPLICATIONS OF THE FINDINGS Our findings provided new insight into the relationship between EMT and neonatal outcomes by showing that a thin endometrium is associated with a decrease in singleton birthweight. STUDY FUNDING/COMPETING INTEREST(S) National Key Research and Development Program of China (2018YFC1003000); the National Natural Science Foundation of China (81771533, 81571397, 31770989, 81671520); the China Postdoctoral Science Foundation (2018M630456). The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER Not applicable.

Pedestrian Injury Severity vs. Vehicle Impact Speed: Uncertainty Quantification and Calibration to Local Conditions

2019 ◽  
Vol 2673 (11) ◽  
pp. 583-592 ◽  
Author(s):  
Gary A. Davis ◽  
Christopher Cheong
Keyword(s):  
Uncertainty Quantification ◽  
Injury Severity ◽  
Likelihood Estimation ◽  
Monte Carlo Sampling ◽  
National Sample ◽  
Local Conditions ◽  
Impact Speed ◽  
Crash Data ◽  
Vehicle Impact ◽  
Pedestrian Crashes

This paper describes a method for fitting predictive models that relate vehicle impact speeds to pedestrian injuries, in which results from a national sample are calibrated to reflect local injury statistics. Three methodological issues identified in the literature, outcome-based sampling, uncertainty regarding estimated impact speeds, and uncertainty quantification, are addressed by (i) implementing Bayesian inference using Markov Chain Monte Carlo sampling and (ii) applying multiple imputation to conditional maximum likelihood estimation. The methods are illustrated using crash data from the NHTSA Pedestrian Crash Data Study coupled with an exogenous sample of pedestrian crashes from Minnesota’s Twin Cities. The two approaches produced similar results and, given a reliable characterization of impact speed uncertainty, either approach can be applied in a jurisdiction having an exogenous sample of pedestrian crash severities.

scholarly journals The impact of project-based organization on competence management practices

2020 ◽  
Vol 9 (2) ◽  
pp. 177-191
Author(s):  
Mohamed Ali Hedhili ◽  
Sami Boudabbous
Keyword(s):  
Management Practices ◽  
Linear Regression Analysis ◽  
Project Managers ◽  
Career Management ◽  
Central Question ◽  
Competence Management ◽  
Training Compensation ◽  
The Impact ◽  
The Relationship ◽  
And Training

The present article aimed at studying the relationship between project-based organization and competence management practices (recruitment, assessment, training, compensation and career management). The central question of our research is formulated as follows: To what extent does project-based organization influence competence management practices? To answer this question, we adopted a quantitative study. A total of 156 Tunisian project managers participated in our survey. We tested our hypotheses through a linear regression analysis. The results show that the majority of competence management practices, namely recruitment, evaluation and training, are more relevant to project-based organizations and thus the three first hypotheses are confirmed. However, other practices, like remuneration and career management, are insensitive to project activities.

scholarly journals What Motivates Medical Students to Engage in Volunteer Behavior During the COVID-19 Outbreak? A Large Cross-Sectional Survey

2021 ◽  
Vol 11 ◽  
Author(s):  
Yu Shi ◽  
Shu-e Zhang ◽  
Lihua Fan ◽  
Tao Sun
Keyword(s):  
Medical Students ◽  
Health System ◽  
Online Survey ◽  
Linear Regression Analysis ◽  
Full Time ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Prosocial Motivation ◽  
The Impact ◽  
The Relationship

After the COVID-19 outbreak, the health status of the general population has suffered a huge threat, and the health system has also encountered great challenges. As critical members of human capital in the health sector, medical students with specialized knowledge and skills have positively fought against the epidemic by providing volunteer services that boosted the resilience of the health system. Although volunteer behavior (VB) is associated with individual internal motivation, there is sparse evidence on this relationship among medical students, especially regarding potential mechanisms. Therefore, this study had two main objectives: (1) to examine the influence of prosocial motivation (PM) of medical students on their VB; and (2) to verify the chain-mediating role of calling and vocation (CV) as well as social responsibility (SR) in the relationship between PM and VB. Study I: a total of 2454 Chinese full-time medical students were invited to complete an online survey. Data analysis was performed using descriptive statistics, Pearson’s correlation coefficient, and multiple linear regression analysis. The results demonstrated that PM significantly affected VB in medical students (β = 0.098, P &lt; 0.001); CV as well as SR chain-mediated the relationship between PM and VB (β = 0.084, P &lt; 0.001). PM promoted the formation of SR by positively evoking CV of medical students, further resulting in increased VB. Study II: A 28 person qualitative interview was conducted. Qualitative data are added to reduce the limitations of online questionnaires. At the same time, we can also critically study the VB of Chinese medical students during COVID-19. The results showed that there were various reasons for medical students to volunteer in the process of fighting against COVID-19, and the experience of volunteer service and the impact on their future life were different. Lastly, the current findings suggest that fostering volunteerism among medical students requires the joint effort of the government, non-profit organizations, and medical colleges.

Macroscopic Spatial Analysis of Pedestrian Crashes in Medellin, Colombia

2018 ◽  
Vol 2672 (31) ◽  
pp. 54-62 ◽  
Author(s):  
Cristhian Lizarazo ◽  
Víctor Valencia
Keyword(s):  
Land Use ◽  
Spatial Econometrics ◽  
Traffic Accidents ◽  
Motor Vehicles ◽  
Transportation Mode ◽  
Spatial Spillovers ◽  
Area Of Interest ◽  
Transportation Modes ◽  
Pedestrian Crashes ◽  
The Impact

Pedestrians are regarded as vulnerable road users as they experience the most severe consequences in collisions with motor vehicles. Pedestrians were involved in fewer than 4% of all traffic accidents but represented more than 12% of traffic fatalities in Medellin, Colombia, from 2009 to 2016. A better understanding of the factors affecting the likelihood of such accidents is an area of interest across local and governmental agencies in Colombia. The paper provides a spatial lag model estimated using spatial two–stage least squares (S2SLS) method to analyze the impact of land use, socioeconomic factors, and transportation modes on vehicle–pedestrian collisions (“crashes”). Consideration is given to spatial spillovers, avoiding inconsistent and inefficient estimates. Commercial land use has a positive correlation with the number of crashes while residential land use correlates with fewer crashes. Analysis of transportation modes demonstrated a higher risk of crashes associated with public transit. In Medellin, buses stop at the passenger’s request instead of at regular bus stops, which increases the likelihood of pedestrians being involved in accidents. The effect of taxi as transportation mode, however, analysed using the number of taxi stands as proxy, is that the number of crashes is reduced. In this transportation mode, the entire trip is covered from point of origin to destination, reducing exposure to the risks of walking. These results might provide a better understanding of the dynamics involved in pedestrian crashes while validating the importance of including spatial econometrics for safety analysis.

Regression Analysis of Pedestrian Fatality Risk and Impact Speed

2014 ◽  
Vol 971-973 ◽  
pp. 1300-1303
Author(s):  
Zhen Zhang ◽  
Gui Fan Zhao ◽  
Na Yang ◽  
Xiao Cheng
Keyword(s):  
Traffic Accidents ◽  
Developed Countries ◽  
Chi Square ◽  
Impact Speed ◽  
Fatality Risk ◽  
Logistic Regression Models ◽  
Chi Square Test ◽  
Pedestrian Traffic ◽  
Long Head ◽  
The Relationship

In order to study the relationship between pedestrian fatality risk and impact speed in domestic pedestrian traffic accidents. According to the frontal shapes of domestic vehicles, this paper divided the vehicle types into long head car, short head car and flat car. Used in-depth accident study method to collect a large number of actual traffic accidents cases. The logistic regression models of pedestrian fatality risk and impact speed of long head car, short head car and flat car were established. The Wald Chi-Square test was used to validate the accuracy of the model. The results shows: The long head car corresponds to the lowest pedestrian fatality risk, the flat car corresponds to the highest values. Compared with developed countries, the developed emergency and medical care play an important role in reducing the pedestrian fatality risk.

scholarly journals The Impact of Marketing Mix on Perceived Value, Destination Image and Loyalty of Tourists (Case Study: Khalkhal City, Iran)

2017 ◽  
Vol 11 (11) ◽  
pp. 96 ◽  
Author(s):  
Saeideh Esmaili ◽  
Nafiseh Rezaei ◽  
Reza Abbasi ◽  
Samane Eskandari
Keyword(s):  
Linear Regression Analysis ◽  
Perceived Value ◽  
Perceived Quality ◽  
Marketing Mix ◽  
Destination Image ◽  
Product Pricing ◽  
Place Promotion ◽  
The Impact ◽  
The Relationship

This study examines the relationship between marketing mix with loyalty, perceived value, perceived quality and destination image. This is an applied descriptive study the aim of which is to determine the impact of marketing mix of services (Product, Pricing, Place, Promotion, People, Process and Physical Evidence) on perceived quality, loyalty, perceived value and destination image of the tourists in Khalkhal city, Iran. Population of the study included all the tourists visiting Khalkhal city from among whom 385 respondents participated in this study. A questionnaire was used for data collection. The conceptual model was analyzed based on linear regression analysis in SPSS software and model fitness was analyzed using LISERL software. Cronbach’s alpha of the questionnaire was equal to 0.791 that is higher than 0.7 and so reliability of the questionnaire was acceptable. Findings of the study showed that promotion, people and physical evidences had the highest effect on perceived value, destination image and perceived quality. Finally, some suggestions were provided for the managers of the tourism destinations to improve the perceived value and quality and also develop a proper destination image.

Research on Simulation and Reconstruction of Vehicle-Pedestrian Collision Based on Multi-Body Dynamics

2012 ◽  
Vol 487 ◽  
pp. 307-311
Author(s):  
Qiu Cheng Wang ◽  
Zhou Kai Xie ◽  
Wei Guo Liu ◽  
Hai Tao Xiao
Keyword(s):  
Traffic Management ◽  
Contact Stiffness ◽  
Major Type ◽  
Impact Speed ◽  
Vehicle Impact ◽  
High Fatality Rate ◽  
Body Dynamics ◽  
Pedestrian Accidents ◽  
Multi Body ◽  
The Impact

Vehicle-pedestrian collision is a major type traffic accident in China, which has been attracted close attention by people because of its high fatality rate. However, it is difficult for traffic management department to reconstruct such kind of accident. In this paper, a methodology for simulation of vehicle-pedestrian accidents based on the multi-body dynamics is presented. A multi-body dummy pedestrian model is established based on PC-CRASH programs, the features that represent the different parts of the pedestrian are defined such as geometry, mass, contact stiffness and coefficients of friction. And more the model is introduced to simulate the collision in a real case of vehicle-pedestrian accident in Hangzhou. Different impact speeds are discussed to predict the different throwing distance of the pedestrian. The relation curves and equations between pedestrian’s throwing distance and vehicle impact speed are established from regression analyses of the simulation data. Finally, the impact speed is estimated with correspond to the exact pedestrian throwing distance.

Sign in / Sign up

Export Citation Format

Share Document