摩托车发动机冷却水套流场特性研究及结构改进

选取CFD流体分析软件STAR-CCM+对摩托车发动机冷却水套进行流场数值模拟及结构改进研究.结果表明,水套原方案缸孔布局不合理,导致冷却水套冷却液流动均匀性较差,排气侧及火花塞侧高温区域冷却较差,不利于高温区域冷却.在水套原方案上减小进气侧缸孔流通面积后,排气侧及火花塞侧冷却液流速明显提升,冷却液利用率提高,保证了高温区域的有效冷却.实验测试结果显示冷却水套结构改进后发动机的缸温降低8℃,表明冷却水套改进结构有效,冷却性能提升明显.研究方法及结果可为摩托车发动机冷却水套的结构设计提供理论参考.     

Conformity to gender stereotypes,motives for riding and aberrant behaviors of French motorcycle riders

As sex differences are very pronounced in motorcycle crashes, both in terms of number and severity, the present study aims to determine the relationship between gender, motives for riding a motorcycle, and risk-taking behaviors among motorcyclists. Declared aberrant behaviors, conformity to gender stereotypes and motives to ride a motorcycle were investigated among 2262 riders of heavy motorcycles, through an Internet survey. Ages ranged from 18 to 78 years, 10.5% of the respondents were women. Results revealed the new scale on motives for riding a motorcycle was effective and allowed to show that competition motives were associated to masculinity, low femininity and youth. They also showed that maleness, masculinity, youth, and competition motives were predictors of violations and femaleness and low masculinity were predictors of lapses. Furthermore, competition motives were also mediators between masculinity and aberrant behaviors, except for personal protective equipment negligence. This study gives new knowledge on the relationship between conformity to gender stereotypes, motivations, and the behaviors of riders of heavy motorcycles. Results can be useful for adapting prevention campaigns to the small sub-groups that are the more at risk in the motorcyclists’ population.     

基于振动控制的摩托车车架结构优化

主、副脚蹬的振动情况是评判摩托车振动舒适性优劣的重要参考.采用测试分析和计算机辅助工程相结合的方法,分析了引起某弯梁摩托车主、副脚蹬振动舒适性较差的根本原因,并依据相关的分析结果设计了控制该车振动的结构优化方案,利用振动测试试验对改进方案的科学性进行了验证.结果表明,结构优化后的车架与原车架相比,主脚蹬在高转速的共振特征被消除,副脚蹬在高速段的振幅急剧放大现象被明显减弱,优化方案有效,整车的振动水平得到较大提升.研究结果可为摩托车车架的结构优化提供参考.     

浅析摩托车电喷系统的匹配技术与开发系统

全文从摩托车电喷系统的概述谈起,然后详细介绍了摩托车使用电喷系统的意义,最后就摩托车电喷系统的匹配技术与开发系统进行了全面的剖析。     

Effectiveness of interventions to prevent motorcycle injuries: systematic review of the literature

Globally, 49% of deaths from traffic crashes occur among vulnerable road users, including pedestrians, bicyclists, and motorcyclists. Approximately, a quarter of those killed are motorcyclists. The authors carried out a systematic review of the literature to evaluate the effectiveness of interventions to prevent motorcycle crashes and the associated morbidity and mortality. The studies included in this review provide evidence for the effectiveness of helmet use, protective clothing, training, and penalties for alcohol consumption and speeding in preventing injury and death to motorcyclists. The use of helmets is effective, especially if it is universally required by law for drivers and passengers. Training to obtain a license also has positive effects but not when it is totally voluntary. There is limited but consistent evidence that strengthening laws for penalties related to alcohol consumption or speeding has an impact on risk. Traffic calming interventions could help reduce crashes in urban areas. In jurisdictions where there is limited regulation or adherence to effective measures, such as the use of helmets, efforts should be directed primarily at expanding such practices. In other areas, efforts can focus on approaches based on alternative effective measures or on more innovative interventions adapted to local conditions.     

Measuring compliance with Viet Nam's mandatory motorcycle helmet legislation

The objective of this roadside observational study was to monitor helmet wearing among motorcycle riders and passengers in three provinces (Yen Bai, Da Nang and Binh Duong) in the Socialist Republic of Viet Nam, before and after a mandatory helmet law took effect on 15 December 2007. A total of 665,428 motorcycle riders and passengers were observed between November 2007 and February 2011 at 45 randomly selected sites covering the entire road network. Across all locations and time periods, correct helmet wearing averaged 40.1% before the law and 92.5% after; however, there were significant differences between time points and locations. The Viet Nam Government's decision to require all motorcycle riders and passengers to wear helmets has been thoroughly implemented nation wide and the results show that high wearing has been sustained. Further study is required on how high helmet wearing has and will translate into a reduction in motorcycle head injuries; however, Viet Nam's motorcycle helmet legislation should be seen as an important policy example for other low- and middle-income countries with a high utilization of motorcycles for personal transport.     

Impact of safe community program on motorcyclists' safety with focus on helmet usage in 14 cities of IR Iran

The aim of this study was to evaluate the effectiveness of safe community interventions on motorcyclists' safety. Two cross sectional observations were conducted in 14 cities (five safe community practicing and nine safe community non-practicing cities) independently on 2005 and 2007. Ten percent of registered motorcycles were observed and interviewed (n=1114 in each observation). 87.9% used motorcycle for commercial purposes. All motorcyclists were male and mostly aged 18–29 years old. Death rate significantly rose from 122 to 254 per 100000 motorcyclists in Fars province since the first observation (p < 0.0001). Helmet usage rate was constant (13%). Recorded crashes increased from 16.4% to 23.1% in safe community setting (p < 0.0001). 11% carried more than one pillion. Heat disturbances, embarrassment, hearing blockage, and negligence were the most mentioned excuses for not using helmet. Law enforcement, public education, accessibility to helmets on discount rate, new legislation and, finally, access to new designed helmet were the most suggestions made by motorcyclists to promote helmet usage. No significant effect was noticed between two settings except in injury registration system in safe community. Community involvement in the safety programs could ensure sustainability of initiatives and continuity of interventions in safe communities.