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191.
本文通过对黄土高原半个世纪治理的反思 ,认为区域产业结构的调整及城市化水平的迅速提高是解决水土流失加剧及环境恶化的根本。同时 ,文章对小流域综合治理模式进行了总结 ,并提出黄土高原水土流失治理在区域综合发展、机制创新、资金筹措等方面应遵循的原则  相似文献   
192.
PROBLEM: Injuries resulting from lifting are costly, and create significant pain and discomfort. While engineering controls are the most effective means of reducing risks, most organizations continue to rely on manual lifting techniques. The problem, however, is that the use of safe-lifting techniques is inconsistent and managers have a difficult time motivating use of these techniques. Consequently, it is important to understand the factors driving safe-lifting behaviors. METHODS: This study used a survey to apply the theory of planned behavior (Ajzen., I., 1991. The theory of planned behavior. Organization Behavior and Human Processes, 50, 179-211) to safe-lifting among 136 materials management employees at a heavy manufacturing organization. Structural equation modeling and factor analysis were employed to analyze relationships among constructs. RESULTS: Results revealed that perceived behavioral control and intention were the strongest predictors of safe-lifting behavior. Subjective norms, to a lesser degree, were also important influences on intention. Attitudes did not surface as effective direct predictors of safe-lifting behavior, but did affect behavior and intent via mediating factors (subjective norms and perceived behavioral control). Finally, the theory of planned behavior was supported as an effective model explaining safe-lifting behavior, and had potential application for many other safety-related behaviors. IMPACT ON INDUSTRY: Results from this study emphasize the importance of perceived behavioral control as a factor associated with safety-related behavior.  相似文献   
193.
晋陕蒙接壤地区的水土流失灾害及其防治   总被引:1,自引:0,他引:1  
常茂德 《灾害学》1992,7(1):51-54
本文对晋陕蒙接壤地区的水土流失情况进行了简要论述,对水土流失的根源进行了探讨,并在此基础上提出了防治水土流失的基本措施。  相似文献   
194.
INTRODUCTION: Cycling accidents in Australia, especially those resulting in head injuries, are a substantive cause of death and disability; but despite legislation and evidence that helmets reduce the risk of head injury, few adolescents wear them. METHOD: This study employed a revised version of the Theory of Planned Behavior (TPB; [Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50, 179-211]) to investigate the determinants of helmet use among a sample of adolescents. Participants in the initial data collection were 294 high school students in Year 8 and Year 11, with 266 completing a follow-up questionnaire measuring behavior over the previous two weeks. RESULTS: Social norms, perceptions of control, and past behavior significantly predicted intentions to use helmets and perceptions of control and past behavior predicted actual helmet use. CONCLUSIONS: Strengthening the routine of helmet use and building young people's confidence that they can overcome any perceived barriers to helmet use will improve adherence to helmet wearing behavior.  相似文献   
195.
INTRODUCTION: We report the first evaluation of the popular "Cyrus the Centipede" child pedestrian safety program. METHOD: A pre-test/post-test control versus experimental condition design was used to assess Cyrus' impact on third graders' pedestrian safety knowledge, and self-reported pedestrian behaviors. RESULTS: Although some beneficial effects were observed, the program was not reliably effective. In particular, the impact of exposure to Cyrus was strongly influenced by the individual teacher who delivered it, likely due to the highly unstructured nature of the curriculum. SUMMARY: We suggest that: (a) the effectiveness and reliability of such programs be demonstrated before they are widely adopted; and (b) programs that focus on training children in actual or simulated traffic environments may be more effective than those that primarily focus on teaching safety facts and rules.  相似文献   
196.
The research questions posed in this study highlight the importance of valuing proactivity in both prompting an individual to engage in proactive behavior and encouraging the expression of that behavior. We integrate a variety of constructs from the proactivity literature to gain a deeper understanding of proactive behavior as it relates to proactive motivation and supervisory performance evaluations. First, we draw upon self‐determination theory, expectancy–value theory, and the recent integration of the proactive motivation literature to hypothesize that proactive behavior is predicted by the interaction of “can do” and “reason to” proactive motivational states. Second, on the basis of performance theory, we hypothesize that the relationship between proactive behavior and performance depends upon the extent to which the supervisor values proactivity. Specifically, we argue that supervisors with proactive personalities are more likely to value and reward subordinate proactive behavior than passive supervisors. Results provide support for both of our hypotheses. Interestingly, results show that proactive behavior did not result in negative consequences but rather that there was a cost (i.e., lower performance rating) for not taking charge for employees with proactive supervisors. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
197.
Implicit psychological constructs are effective predictors of behavioral outcomes but are rarely used in organizational settings because of real or imagined problems with measurement validity and administration. To address these concerns, we present a means of assessing implicit constructs quickly and easily by using psychological capital as an example. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
198.
为评价物料混合对危险化学品热化学行为的影响,采用热分析-红外/质谱联用技术(TA-FTIR/MS)研究硝酸铵、柠檬酸和蔗糖的混合物的热化学行为。通过对硝酸铵及其混合物的分解温度和分解过程中逸出气体的分析,发现硝酸铵、柠檬酸和蔗糖的混合物热分解温度分别降低至135℃和153℃,而硝酸铵与甲基纤维素的混合物分解温度与硝酸铵基本相同为201℃,且各混合体系的气相分解产物均有氮氧化物(NOX),H2O和CO2。结果表明,混合物受热后其中的硝酸铵首先分解为硝酸和氨气;酸性物质和还原性物质由于对硝酸的分解反应有催化作用,使得混合物的热稳定性下降。  相似文献   
199.
Large TNT equivalent explosions usually arise from accidents occurring during the transportation, storage, and manufacturing of chemicals relevant to process industries. The blast wave generated by the explosion will spread and interact with the surrounding factories and storehouses, damaging the building structures within several kilometers and causing significant casualties and property losses. This study aims to develop an efficient numerical simulation method to predict blast loads to estimate the consequences of accidents involving far-field free air bursts or surface burst explosions. Before its interaction with the interested target, a blast wave is generated in the numerical model by specifying the initial and boundary conditions of the disturbed air. Based on empirical data of incident overpressure, an explicit formula to calculate the air particle velocity is derived from the governing equations of a perfect inviscid gas. A simplified path line method is proposed to calculate the air density. The proposed method is applied to the LS-DYNA CESE solver to simulate the blast loads on building structures in the far field. Validations against empirical data and experiments indicate that the proposed method is sufficiently accurate for engineering applications and, through a case study, presents a more efficient performance than the LOAD_BLAST_ENHANCED (LBE) and mapping methods.  相似文献   
200.
Understanding human behavior is vital to developing interventions that effectively lead to proenvironmental behavior change, whether the focus is at the individual or societal level. However, interventions in many fields have historically lacked robust forms of evaluation, which makes it hard to be confident that these conservation interventions have successfully helped protect the environment. We conducted a systematic review to assess how effective nonpecuniary and nonregulatory interventions have been in changing environmental behavior. We applied the Office of Health Assessment and Translation systematic review methodology. We started with more than 300,000 papers and reports returned by our search terms and after critical appraisal of quality identified 128 individual studies that merited inclusion in the review. We classified interventions by thematic area, type of intervention, the number of times audiences were exposed to interventions, and the length of time interventions ran. Most studies reported a positive effect (n = 96). The next most common outcome was no effect (n = 28). Few studies reported negative (n = 1) or mixed (n = 3) effects. Education, prompts, and feedback interventions resulted in positive behavior change. Combining multiple interventions was the most effective. Neither exposure duration nor frequency affected the likelihood of desired behavioral change. Comparatively few studies tested the effects of voluntary interventions on non-Western populations (n = 17) or measured actual ecological outcome behavior (n = 1). Similarly, few studies examined conservation devices (e.g., energy-efficient stoves) (n = 9) and demonstrations (e.g., modeling the desired behavior) (n = 5). There is a clear need to both improve the quality of the impact evaluation conducted and the reporting standards for intervention results.  相似文献   
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