Reliability and validity of the Multidimensional Driving Style Inventory in Chinese drivers

Objective: The Multidimensional Driving Style Inventory (MDSI) has been widely used in assessing the associations between driving styles and traffic violations and accidents in different cultural contexts. Due to the lack of a valid instrument to assess driving style, studies concerning driving style and its influence factors are limited in China. Thus, this study aimed to adapt and validate a Chinese version of the MDSI.

Methods: Seven hundred and sixty drivers aged from 19 to 60 years old were asked to complete the MDSI and a personality scale (trait anger, sensation seeking, altruism, and normlessness). Exploratory factory analysis (EFA) and confirmatory factor analysis (CFA) were used to obtain the factorial structure of the MDSI. The external validity of the MDSI was then evaluated by examining the associations between driving styles and personality traits, demographic variables, and traffic violations and crashes.

Results: EFA revealed a 6-factor structure of the MDSI (i.e., risky, anxious, angry, distress reduction, careful, and dissociative driving styles). CFA confirmed that the model fit of the MDSI was acceptable. The MDSI factors were moderately or weakly correlated with trait anger, sensation seeking, altruism, and normlessness. Significant gender and age differences in driving styles were found. Moreover, drivers who had traffic violations or crashes in the past year scored higher on risky and angry driving styles and lower on careful driving style than those who had not have traffic violations or crashes.

Conclusions: The Chinese version of the MDSI proved to be a reliable, valid, and highly useful instrument. It could be used to assess Chinese drivers who are at risk due to their maladaptive driving styles.     

清洁生产在石油钻探行业中的应用

在介绍清洁生产理念的基础上,通过对石油钻探生产现状的分析,大量的引证了在钻探过程中应用清洁生产的可能性。对减轻钻井作业的末端处理负担,预防由于末端处理不完全造成的环境污染等方面作出了有益的探索。     

Minimax regret optimization analysis for a regional solid waste management system

Solid waste management (SWM) facilities are crucial for environmental management and public health in urban regions. Due to the waste management hierarchy, one of the greatest challenges that organizations face today is to figure out how to diversify the treatment options, increase the reliability of infrastructure systems, and leverage the redistribution of waste streams among incineration, compost, recycling, and other facilities to their competitive advantage region wide. Systems analysis plays an important role for regionalization assessment of integrated SWM systems, leading to provide decision makers with break-through insights and risk-informed strategies. This paper aims to apply a minimax regret optimization analysis for improving SWM strategies in the Lower Rio Grande Valley (LRGV), an economically fast growing region in the US. Based on different environmental, economic, legal, and social conditions, event-based simulation in the first stage links estimated waste streams in major cities in LRGV with possible solid waste management alternatives. The optimization analysis in the second stage emphasizes the trade-offs and associated regret evaluation with respect to predetermined scenarios. Such optimization analyses with multiple criteria have featured notable successes, either by public or private efforts, in diverting recyclables, green waste, yard waste, and biosolids from the municipal solid waste streams to upcoming waste-to-energy, composting, and recycling facilities. Model outputs may link prescribed regret scenarios in decision making with various scales of regionalization policies. The insights drawn from the system-oriented, forward-looking, and preventative study can eventually help decision-makers and stakeholders gain a scientific understanding of the consequences of short-term and long-term decisions relating to sustainable SWM in the fast-growing US-Mexico borderland.     

Methane and carbon dioxide emissions from Shan-Chu-Ku landfill site in northern Taiwan

To investigate the methane and carbon dioxide emissions from landfill, samples were taken of material up to 5 years old from Shan-Chu-Ku landfill located in the northern part of Taiwan. Atmospheric concentrations of carbon dioxide, methane and nitrous oxide ranged from 310 to 530, 2.64 to 20.16 and 0.358 to 1.516 ppmv with the measurement of gas-type open-path Fourier transform infra-red (FTIR) spectroscopy during February 1998 to March 2000, respectively. Average methane emission rate was 13.17, 65.27 and 0.99 mgm(-2)h(-1) measured by the gas chromatography chamber method in 1-2, 2-3 and 5 year-old landfill, respectively. Similarly, average carbon dioxide emission rate was 93.70, 314.60 and 48.46 mgm(-2)h(-1), respectively. About 2-3 year-old landfill had the highest methane and carbon dioxide emission rates among the tested areas, while 5 year-old landfill was the least. Methane emission rate at night in most tested locations was higher than that in the daytime. Total amount of methane and carbon dioxide emission from this landfill was around 171 and 828 ton in 1999, respectively.     

Box-Behnken响应面分析法对双阳极电Fenton法处理垃圾渗滤液工艺的优化

采用双阳极电Fenton法处理垃圾渗滤液,并在阴极曝气。应用Box-Behnken响应面分析法对电Fenton法处理的结果进行了优化,将Fe2+投加量、电压、和反应时间3个因素进行实验设计,得到二次响应曲面模型。响应面分析表明,Fe2+投加量与反应时间的交互作用对COD去除率影响最大,其次是电压与反应时间的交互作用。优化后的结果:Fe2+投加量、电压、和反应时间分别为3 219.2 mg/L、6.11 V和180 min。模型方差分析得到F值和R2分别为24.2和0.977,说明该二次方程是显著的,模型在整个回归区域内拟合好,能够很好地反映电Fenton法处理垃圾渗滤液的过程。     

基于RS与GIS的武汉城市湖泊演化研究

以武汉市主城区为例,利用1995和2005年Landsat5两期TM影像与2000和2010年Landset7两期ETM＋影像的解译结果,基于景观分形理论与GIS的空间分析功能相结合的研究方法,分别构建湖泊变化强度指数和湖泊分形维数变化指数。从湖泊面积变化和湖泊形态变化,以及湖泊水域和其他土地利用类型的转移变化特点与影响进行综合分析。来丰富湖泊演化的分析方法,并总结高速城市化背景下湖泊的变化规律,从而更深入地了解和认识人类活动因素与湖泊水域动态变化之间的响应关系,同时提出若干城市湖泊治理与管理的方式。研究结果表明,（1）15年间的湖泊水域面积总量的变化呈现萎缩的趋势,年变化量在逐渐减小,湖泊萎缩的速度得到了一定的控制。（2）1995-2010年湖泊分形维数也呈逐期较小趋势,说明湖泊几何形状趋于简单化,人为活动对湖泊的影响加大。（3）15年来主城区28个主要湖泊的变化强度指数均为负值,呈萎缩趋势。但从2000年开始,少数湖泊变化强度指数为正值,萎缩趋势得到初步的控制。（4）1995-2010年间湖泊的水域面积主要转移成为建设用地和耕地。其转移面积占转移总面积的87．02％。围湖造田和城市化率的迅速提高对城市湖泊的演化影响深刻。（5）城市化背景下湖泊面积与形态变化的规律并非完全与城市化发展速率呈正比的关系,当城市化率上升到一定的阶段后,城市内部对生态环境的保护与要求也不断提高。为改善城市环境和城市内部的生态用地,湖泊应得到立法等强制性保护。     

Biofiltration of trimethylamine-containing waste gas by entrapped mixed microbial cells

The study provides novel attempt to use an aerobic biofiltration system containing entrapped mixed microbial cells (EMMC) for removal of (CH3)3N-dominant waste gases. In the study, heterotrophic microflora-immobilized cellulose was packed into an EMMC reactor to degrade (CH3)3N. Effects of (CH3)3N inlet concentrations in continuous mode of operation at various flow rates are indicated. The result indicated that the (CH3)3N removal efficiency is higher than 90% at inlet loading below 27.2 mgNh(-1) and retention time 5.3 min. In addition, the maximal mass loading to reach approximately 99% efficiency was 95.5 mgNh(-1) for trimethylamine treatment. This EMMC biofiltration system also showed higher tolerance to endure fluctuations in concentrations and flow rates and still maintained in stable performance for removal. Adaptability test in response to gradual shift up and down of inlet TMA loading indicated that lack of steady-state multiplicity and hysteresis guarantees the microbial communities more precisely adapted to continuous treatment for maintaining stability.     

微囊藻毒素对青菜生长的影响及其在生物体内的累积

蓝藻藻泥好氧堆肥腐熟后还田是其打捞后资源化利用的主要途径。堆肥后仍有一定数量的微囊藻毒素(microcystin,MC)残留,大量还田是否会对作物生长和人类健康产生安全风险尚不明确。将青菜(Brassica chinensis)暴露于不同MC含量的石英砂和菜地土壤,观测植株生长状况及体内MC含量,并观测不同含量的MC在菜地土壤中的降解速率。结果发现:砂培实验结束时,青菜成株的株高和生物量随着MC暴露浓度的增加而显著降低,而植株地上部MC的含量则显著增加。在MC浓度为0.386mg·kg-1的处理中,青菜地上部MC-LR(L为亮氨酸)和MC-RR(R为精氨酸)的浓度分别达到27.45μg·kg-1(鲜质量)和1.35μg·kg-1(鲜质量)。MC-LR和MC-RR在青菜地上部的富集系数都随着砂培基质中MC浓度的增加而显著降低,且前者显著高于后者。土培青菜生长过程中吸收和累积的MC数量显著小于砂培实验。MC在菜地土壤中降解56d后,MC-LR和MC-RR的降解率均达90%以上。按普通有机肥的一般用量(2.5kg·m-2)施用充分腐熟的蓝藻堆肥成品种植青菜,食用后每人每天摄入的MC含量远低于WHO制定的饮用水中MC的指导值。研究为评估现行蓝藻堆肥工艺中残留的MC对作物生长和生物安全风险提供了科学依据。     

A comparison of required coefficient of friction for both feet in level walking

The required coefficient of friction (RCOF) is one of the critical elements in determining whether a slip incident might occur. Most researchers, when measuring RCOF, do not differentiate between the two feet of the same participant under the same walking condition. Results from a recent study (Chang et al., 2010) indicated that the stochastic distributions of the RCOF of both feet were different in 76% of the cases. Using the previous data (Chang et al., 2010), this paper presents a comparison of the RCOF for both feet of 50 participants under four level walking conditions resulting from two footwear types and two walking speeds using a t-test, commonly used by safety professionals to compare two pools of data. The current results indicated that 78% of the RCOF data showed a statistically significant difference between the RCOF from two feet for the same participant under each walking condition. The results of the logistic regression analysis used to identify factors that contributed to the outcome of the t-test indicated that the walking speed was the only factor with a statistical significance (p = 0.044).     

Evaluation of the emission characteristics of PCDD/Fs from electric arc furnaces

Distribution of PCDD/F (polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran) congeners at two electric arc furnaces (EAFs) in Taiwan is evaluated via intensive stack sampling and analysis. Two kinds of exhaust system in EAFs including stack system and shutter system are selected for measuring dioxin emissions. In addition, dioxin emissions during oxidation and reduction stages at EAF-A were characterized. Results indicate that the PCDD/F concentration of stack gas in EAF-A was 4.39 ng/N m³ while total Toxic Equivalent Quantity (TEQ) concentration was 0.35 ng I-TEQ/N m³. The PCDD/F concentration of stack gas in EAF-B was 2.20 ng/N m³ and the TEQ concentration was 0.14 ng I-TEQ/N m³. 1,2,3,4,6,7,8-H_pCDF, OCDD and OCDF are the major contributors of the dioxin concentrations for two EAFs investigated and the percentage of PCDD/F in particulate phase increases as the chlorination level of the PCDD/F congener increases. The results obtained on gas/particulate partitioning of PCDD/Fs in flue gases prior to the APCD in EAFs indicate that more than 90% exists in particulate phase. In EAF-A, the PCDD/F concentration during oxidation stage is slightly higher than that measured during reduction stage, including the sampling points of CO converter outlet, prior to bag filter and stack. Majority of PCDD/Fs emitted from steel-making processes exists in particulate-phase (about 60–70%) at both EAFs investigated.