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41.
在水工水力学模型研究成果基础上,采用MC法对现役大坝泄洪能力风险率做进一步探讨,研究表明:(1)水力的不确定性对大坝防洪安全确实存在影响,但风险值较小;(2)国内绝大多数大中型现役坝的水力风险几近为0,设计偏于保守.由此可见,确定基于风险分析的大坝防洪安全标准和设计洪水标准,并据此来确定大坝坝顶高程,是非常必要的.  相似文献   
42.
Objective: Guided by the extended parallel process model (EPPM), the objective was to assess control processes dominant in influenza behavior decisions. Design: Cross-sectional survey. Results: Response rate was 31% (n=968). Regarding influenza risk, 59% were in danger control. Those in fear control were more likely to report influenza infection (p=.000). In the nonvaccinated, those in fear control were more likely to indicate not knowing where to get the vaccine (p=.016) and that it was unavailable (p=.027), and those in danger control believed they did not need it (p=.023). Zero critical values were more likely to indicate that no health provider recommended the shot (p=.002). Conclusions: Most perceived efficacy to be stronger than threat related to influenza; according to the EPPM, they are aware of their risk but recognize their ability to avert it. For those in danger control, messages should focus on increasing perceptions of severity and susceptibility to positively affect behavior change. For those in fear control, messages should focus on efficacy only. With a critical value of zero, no threat is induced, and a high-threat/high-efficacy approach should be taken. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
水利工程建设项目的风险分析   总被引:2,自引:0,他引:2  
水利工程建设中潜藏着众多风险,对风险进行有效分析是工程顺利建设的重要保证。水利工程风险分析是由风险识别、估算、评价、管理、控制决策等组成的科学体系。明确了水利工程中风险的定义,识别了水利工程的风险因素,论述了风险估算和评价的方法,并提出对工程风险进行管理和控制,以保证工程建设顺利进行。  相似文献   
44.
The authors present a theory for understanding risk for problem drinking among reservation-dwelling American Indians. The theory offers an overall framework for understanding the risk process for this group. It considers the distinction between factors that influence mean levels of American Indian problem drinking and factors that influence individual differences in American Indian drinking. It proposes important contextual differences between reservation-dwelling American Indians and Caucasians that may help explain the higher mean levels of American Indian problem drinking. The theory further holds that, within the high mean level of problem drinking characteristic of many American Indian reservations, individual differences in problem drinking can be explained by very similar personality and learning factors as those that influence problem-drinking levels for other ethnic groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
45.
Longitudinal data from a representative sample of 1,978 Black and White adolescents were used to examine the role of personality in multiple risk or problem behaviors. Results indicate that covariation among diverse behaviors (educational underachievement, delinquent behavior, substance use, sexual behavior) can be adequately modeled by a single higher order factor, and that impulsivity and avoidance coping serve as generalized risk factors for involvement in these behaviors. Whereas none of the personality variables examined explained change in problem behaviors once established, avoidance coping prospectively predicted involvement among a subgroup of adolescents with little or no prior involvement. Results suggest that dysfunctional styles of regulating emotions and emotionally driven behaviors are core features of risky or problem behaviors during adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
46.
Community violence has emerged as a major risk factor for the development of mental health problems in children and adolescents. If mental health providers are to meet the needs of children and communities dealing with community violence, then they will need to integrate principles from various subdisciplines in psychology (e.g., developmental psychology, school psychology, developmental psychopathology) as well as disciplines outside of psychology (e.g., sociology, public health, medicine) to understand fully the developmental impact of exposure to community violence. The development of such a model is necessary to identify the pathways, risk, and protective factors on which prevention and intervention programs can be built. The goal of this article is to present an ecological-transactional model of community violence as a conceptual framework for understanding the existing literature and for guiding future research on community violence exposure and child development. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
47.
Alcohol expectancy-challenge programs are effective in changing expectancies and reducing drinking in college men (J. Darker & M. S. Goldman. 1993. 1998); however, recent evidence suggests this protocol might not be effective for women (M. E. Dunn, C. Lau, & I. Y. Cruz, 2000). This study was designed to reevaluate the effectiveness of a social/sexual expectancy-challenge intervention in college women reporting moderate to heavy alcohol use. Forty-six undergraduate women were randomly assigned to the prevention or control condition. Participants reported alcohol expectancies at pre- and posttest and monitored their drinking patterns daily for 6 weeks. The program was effective in changing some expectancies but did not reduce drinking. This further confirms differences in the mechanisms by which expectancy-challenge programs function for men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
48.
This article examines the psychological impact of participating in sigmoidoscopy screening for colorectal cancer prevention. The 1st study examined psychological well-being at 3 months, in relation to screening outcome, in 4,153 individuals. The 2nd study used longitudinal data to examine changes in psychological functioning from before to after screening in relation both to screening outcome and baseline indicators of vulnerability. There were few psychological differences between those who had received negative results or had polyps detected. These findings were confirmed in the longitudinal study, which also found no evidence for vulnerability to adverse effects among those who were initially most anxious or who perceived their risk of cancer to be higher. The longitudinal data suggested that screening might produce transient positive effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
Risk factors affecting the course of posttraumatic stress disorder (PTSD) are poorly understood. As part of a larger study on characterizing exposure to herbicides in Vietnam, the authors investigated this issue in a random sample of 1,377 American Legionnaires who had served in Southeast Asia during the Vietnam War and were followed over a 14-year period. High combat exposure, perceived negative community attitudes at homecoming, minority race, depression symptoms at Time 1, and more anger at Time 1 predicted a more chronic course. Community involvement at Time 1 was protective and associated with decreased risk at Time 2. Discomfort in disclosing Vietnam experiences was associated with an increased risk for developing PTSD but did not predict its course. Combat exposure predicted PTSD course more strongly than any other risk factor. Findings suggest recovery from PTSD is significantly influenced by perceived social support. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
潘凤丽  刘峰 《有色矿冶》2003,19(3):63-65
针对目前大多数科研单位在内部会计控制中存在的问题,探讨了科研单位在转制过程中应如何建立和完善内部会计控制制度,以达到防范经营风险,保护资产安全、完整,促进单位经营管理目标和政策有效实施。  相似文献   
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