The Influence of Anchor Devices on the Performance of Retractable Type Fall Arresters Protecting Against Falls From a Height

Retractable type fall arresters are part of the equipment used for protecting people against falls from a height. They are an intermediate part between full body harness worn by a man and the structural anchor at the worksite. The most important task of retractable type fall arresters is to arrest people’s falls and to reduce their harmful consequences. Information received from users as well as laboratories testing protective equipment indicates that the performance of such equipment is incorrect under specific conditions. The paper is concerned with an analysis of the conditions in which retractable type fall arresters demonstrate intermittent performance and with an explanation of that phenomenon. The results of tests investigating anchor devices and the performance of retractable type fall arresters are presented. External and internal factors contributing to intermittent performance have been determined and guidelines for safer use of these devices have been developed.     

Efficiency of Filtering Materials Used in Respiratory Protective Devices Against Nanoparticles

The basic aim of this research was to establish the efficiency of filtering materials widely used in respiratory protection devices with particular interest in their porosity, degree of electric and changeable process parameters, such as the flow rate of the test nanoaerosol and the size range of nanoparticles. Tests were carried out with an NaCl solid aerosol of 3.2 × 10⁵ particles/cm³ for the range of particle size of 7–270 nm, at aerosol flow rate of 1800, 2700, 3600, 4500 and 5400 L/h. The tests showed that electrospun nonwovens were the most effective filtering materials for nanoparticles over 20 nm. Melt-blown electret nonwovens with lower porosity than electrospun nonwovens had higher values of penetration of 1%–4%. Those materials provided very efficient protection against nanoparticles of certain sizes only.     

Effects of deodorants on treatment of boat holding-tank waste

A literature search and survey of Virginia, USA, campgrounds with RV pump-out stations were used to determine whether boat holding-tank deodorant chemicals would have deleterious effects on marina septic systems or package treatment plants. Laboratory studies reported in the literature indicate that these chemical additives could affect septic system function in three ways: (1) active ingredients in the additives can impair sewage degradation in septic tanks, causing sludge buildup and overflow of solids into the drainfield, (2) additive chemicals might enter the drainfield and, in high enough concentrations, reduce the drainfield's ability to degrade waste, or (3) toxic additive chemicals might migrate from the drainfield to ground or surface water. Laboratory studies also show that some ingredients added to holding tanks interfere with functioning of activated sludge treatment process. Experience in the field and in other laboratory studies suggests that factors such as dilution of treated waste with untreated waste and the characteristics of the sewage to be treated can reduce the possibility of damage to septic and activated sludge systems. The campground owners surveyed indicated that they have few problems with their septic systems in spite of the presence of chemical additives in the RV waste. However, most of them practice good septic system maintenance and have devised other means of ensuring that their systems function efficiently. In addition, the survey indicates that most Virginia campgrounds get only seasonal use (as would marinas in Virginia), allowing their systems to recover between peak seasons.     

上海市在用车监测与维修制度探讨

根据上海市机动车辆的管理现状，提出上海市在用车I/M制度体系网络、监测方法、数据收集网络与“通过/不通过”排放限值方面的基本设想，为建立一个真正有效的在用车监测与维修制度提供依据。     

可燃有毒气体报警仪系统设置现状及应用探讨

针对当前可燃、有毒气体报警仪系统管理的日趋严格,综合归纳了在役装置可燃、有毒气体报警仪系统设置现状,重点分析了在役装置报警仪系统的不足及在实际应用中常见的问题,并提出相关整改建议和注意事项。     

几种典型除尘器收集效率的扩散模型研究

在气流速度均匀假设下用扩散理论建立了在重力沉降室、离心式除尘器和静电除尘器中粉尘粒子的浓度分布，由此浓度分布模型和除尘效率定义得出这3种典型除尘器的分级除尘效率具有相同的表达式：η=1—exp(-Dλ^2L/u)．为了使这一由扩散理论导出的分级效率公式能够用于实际计算，给出了扩散系数D的确定方法和常数λ的计算式．     

Young drivers' responses to anti-speeding advertisements: Comparison of self-report and objective measures of persuasive processing and outcomes

Objective: Self-report measures are typically used to assess the effectiveness of road safety advertisements. However, psychophysiological measures of persuasive processing (i.e., skin conductance response [SCR]) and objective driving measures of persuasive outcomes (i.e., in-vehicle Global Positioning System [GPS] devices) may provide further insights into the effectiveness of these advertisements. This study aimed to explore the persuasive processing and outcomes of 2 anti-speeding advertisements by incorporating both self-report and objective measures of speeding behavior. In addition, this study aimed to compare the findings derived from these different measurement approaches.

Methods: Young drivers (N = 20, M age = 21.01 years) viewed either a positive or negative emotion–based anti-speeding television advertisement. While viewing the advertisement, SCR activity was measured to assess ad-evoked arousal responses. The RoadScout GPS device was then installed in participants' vehicles for 1 week to measure on-road speed-related driving behavior. Self-report measures assessed persuasive processing (emotional and arousal responses) and actual driving behavior.

Results: There was general correspondence between the self-report measures of arousal and the SCR and between the self-report measure of actual driving behavior and the objective driving data (as assessed via the GPS devices).

Conclusions: This study provides insights into how psychophysiological and GPS devices could be used as objective measures in conjunction with self-report measures to further understand the persuasive processes and outcomes of emotion-based anti-speeding advertisements.     

Experimental investigation of the effect of occupant characteristics on contemporary seat belt payout behavior in frontal impacts

Objective: The goal of this study was to investigate the influence of the occupant characteristics on seat belt force vs. payout behavior based on experiment data from different configurations in frontal impacts.

Methods: The data set reviewed consists of 58 frontal sled tests using several anthropomorphic test devices (ATDs) and postmortem human subjects (PMHS), restrained by different belt systems (standard belt, SB; force-limiting belt, FLB) at 2 impact severities (48 and 29 km/h). The seat belt behavior was characterized in terms of the shoulder belt force vs. belt payout behavior. A univariate linear regression was used to assess the factor significance of the occupant body mass or stature on the peak tension force and gross belt payout.

Results: With the SB, the seat belt behavior obtained by the ATDs exhibited similar force slopes regardless of the occupant size and impact severities, whereas those obtained by the PMHS were varied. Under the 48 km/h impact, the peak tension force and gross belt payout obtained by ATDs was highly correlated to the occupant stature (P =.03, P =.02) and body mass (P =.05, P =.04), though no statistical difference with the stature or body mass were noticed for the PMHS (peak force: P =.09, P =.42; gross payout: P =.40, P =.48). With the FLB under the 48 km/h impact, highly linear relationships were noticed between the occupant body mass and the peak tension force (R² = 0.9782) and between the gross payout and stature (R² = 0.9232) regardless of the occupant types.

Conclusions: The analysis indicated that the PMHS characteristics showed a significant influence on the belt response, whereas the belt response obtained with the ATDs was more reproducible. The potential cause included the occupant anthropometry, body mass distribution, and relative motion among body segments specific to the population variance. This study provided a primary data source to understand the biomechanical interaction of the occupant with the restraint system. Further research is necessary to consider these effects in the computational studies and optimized design of the restraint system in a more realistic manner.     

常宁庙前自然风景区景观规划与设计

庙前自然风景区是常宁市天堂山旅游风景区的四大景区之一,它以自然地貌的溶洞、溶岩、峰谷、石林为景观特色,本文就充分利用这些奇特的自然景观资源进行了详细规划,并提出了切实可行的建议。     

Science-practice interactions linked to climate adaptation in two contexts: municipal planning and forestry in Sweden

This paper examines the science-practice interface in the process of adapting to climate change in society. This paper analyses science-based stakeholder dialogues with climate scientists, municipal officers and private individual forest owners in Sweden, and examines how local experts both share scientific knowledge and experience and integrate it into their work strategies and practices. The results demonstrate how local experts jointly conceptualise climate adaptation, how scientific knowledge is domesticated among local experts in dialogue with scientific experts, the emergence of anchoring devices, and the boundary-spanning functions that are at work in the respective sectors.