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131.
以上海市5条隧道为研究对象,采用车载移动监测的方式监测记录各条隧道沿程颗粒物(PM_(2.5)和PM_(10))的质量浓度,结合隧道自身特点,探究隧道内部颗粒物分布规律和成因。结果表明:隧道内颗粒物质量浓度分布主要与隧道自身的通风方式、结构特点和通过的车辆及其形成的活塞风有关。通过平行比较5条隧道的通风效果,发现翔殷路隧道通风效果较好,人民路隧道北线污染较为严重。  相似文献   
132.
根据救生舱舱体结构,构建舱体隔热层填充材料隔热性能测定系统;利用该系统,分别测定了硅酸铝针刺毯、复合硅酸盐毡和膨胀蛭石粉自身的隔热性能;结合舱体结构特点,制作救生舱模拟结构层;在钢板内侧粘贴铝箔,构建双层防护隔热结构;测定结果表明复合硅酸盐毡最适合作为救生舱隔热层的填充材料;利用修正函数计算出复合硅酸盐毡的厚度为100mm,对该厚度材料的隔热性能进行测定,试验结果证明其可行。  相似文献   
133.
综述了手机辐射的原理、辐射危害、辐射场计算和辐射评价技术标准及其检测仪器,并提出了一些减小手机辐射的措施和建议.  相似文献   
134.
Objective: Motorcycle crashes are a significant road safety challenge, particularly in many low- and middle-income countries where motorcycles represent the vast majority of their vehicle fleet. Though risky riding behaviors, such as speeding and riding under the influence of alcohol, have been identified as important contributors to motorcycle crashes, little is understood about the effect of using a mobile phone while riding on motorcycle crash involvement. This article investigates crash involvement among motorcycle riders with risky riding behaviors, particularly using a mobile phone while riding.

Methods: Data were obtained from an online survey of university students’ risky riding behaviors in Vietnam administered between March and May 2016 (n?=?665).

Results: Results show that 40% of motorcycle riders reported to have experienced a crash/fall and nearly 24% of motorcycle riders indicated that they had been injured in a crash/fall. Effects of mobile phone use while riding on safety of motorcycle riders are highlighted. Specifically, more frequent use of a mobile phone for texting or searching for information while riding is associated with a higher chance of being involved in a crash/fall. The results also show that drink riding is associated with a higher chance of being injured.

Conclusions: Overall this article reveals significant safety issues of using a mobile phone while riding a motorcycle, providing valuable insight for designing education and publicity campaigns.  相似文献   
135.
Objective: The objective of this study was to investigate the prevalence of calling, texting, and searching for information while riding a motorcycle among university students and the influences of sociodemographic characteristics, social norms, and risk perceptions on these behaviors.

Methods: Students at 2 university campuses in Hanoi and Ho Chi Minh City, the 2 largest cities in Vietnam, were invited to participate in an anonymous online survey. Data collection was conducted during March and May 2016.

Results: There were 741 respondents, of whom nearly 90% of students (665) were motorcycle riders. Overall prevalence of mobile phone use while riding is 80.9% (95% confidence interval [CI], 77.9–83.9%) with calling having a higher level of prevalence than texting or searching for information while riding: 74% (95% CI, 70.7–77.3%) vs. 51.7% (95% CI, 47.9–55.5%) and 49.9% (95% CI, 46.1–53.7%), respectively. Random parameter ordered probit modeling results indicate that mobile phone use while riding is associated with gender, motorcycle license duration, perceived crash risk, perceived risk of mobile phone snatching, and perceptions of friends' mobile phone use while riding.

Conclusions: Mobile phone use while riding a motorcycle is highly prevalent among university students. Educational programs should focus on the crash and economic risk of all types of mobile phone use while riding, including calling, texting, and searching for information. In addition, they should consider targeting the influence of social norms and peers on mobile phone use while riding.  相似文献   

136.
The aim of this study is to identify management practices that effectively reduce greenhouse gas (GHG) emissions with regard to the green supply chain adopted by mobile phone producers. Six cases were surveyed (Apple, Samsung, LG, Huawei, Nokia, and ZTE). The main source of data was sustainability reports, which were retrieved from the Global Reporting Initiative database. A special data analysis technique called rank analysis was adopted. The results revealed that the effective practices to reduce GHG 1 emissions were related to production process and business travel; those that were effective for reducing GHG 2 emissions were related to facilities accreditation and energy saving; and those effective in reducing GHG 3 emissions were related to logistics and customer practices. No effective actions related to the management of relationships with suppliers were identified by this study. Indicative models for the relationship between actions and GHG emissions were developed, as was a value‐stream map. The previous studies reporting the effective practices in other industries reported results for reducing GHG 1 or GHG 3, or overall GHG emissions, without discriminating among the actions taken to reduce such emissions, although some limited actions were reported. This study describes the effective practices along the whole supply chain—both upstream and downstream—and it also lists the actions related to addressing all the emissions, whether GHG 1, 2, or 3.  相似文献   
137.
We advocate a more formal structural approach for comparing WTP for non-market or pre-test-market goods conveyed by fundamentally different preference elicitation mechanisms. Seven independent samples of respondents were asked to value the identical good. Elicitation methods include one actual purchase and six widely used hypothetical choice formats. Using a common underlying indirect utility function (and stochastic structure) allows data for different elicitation methods to be used independently, compared pair-wise (as in much of the earlier literature) or pooled across all samples in one unified model with heteroscedasticity across elicitation methods. Our differences in estimated WTP for the individual models are typical of earlier findings. However, pooled-data models that allow for heteroscedasticity reveal that while there are substantial differences in the amount of noise in the different samples, a common underlying systematic component of the preference structure cannot be rejected for at least four (and possibly five) of these seven elicitation methods.  相似文献   
138.
机动车排放污染与城市交通环境   总被引:7,自引:0,他引:7  
分析了城市机动车排放污染的状况及影响因素,特别重点讨论了机动车车型和汽车城市道路运行工况对机动车排放污染物的影响,提出了改善城市交通环境的若干措施。  相似文献   
139.
以我国山东省北部为例 ,研究了冲积物覆盖区土壤中金属的存在形式 ,特别是活动态金属的分配规律。通过研究发现 ,活动态Au在土壤全量Au中大约占到 70 %的比例 ,而Cu、Pb、Zn等元素在土壤中所占的比例相对较小。每种金属在四种活动态中的分配比例也存在较大差别。造成这些差别的主要原因是元素的地球化学性质不同 ,特别是地球化学性质极为不活泼的Au ,反而大部分以活动形式存在 ,主要是因为Au在表生环境中以纳米或亚微米等超微细颗粒形式存在 ,使其化学性质发生了很大的变化。  相似文献   
140.
张磊  邓良  查睿  祝愿 《地球与环境》2018,46(2):197-203
在通过天地图API获取基础地理信息并辅以地质灾害专题数据的基础上,研究了移动GIS、Web API、LBS等技术的融合运用,结合地质灾害业务管理流程,设计开发出一套地灾管理系统。根据应用环境不同系统分为移动终端和指挥管理平台两套子系统,移动终端主要实现灾点现场调巡查记录、业务分析、速报及数据上传,指挥管理后台主要实现数据分析、任务指派和信息管理等功能。应用实例中针对移动GIS端与Web端的数据管理和交互反馈作出评述,并就未来应用方向作出展望。  相似文献   
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