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111.
112.
Peter E. Black 《Journal of the American Water Resources Association》1970,6(2):153-162
Three fundamental concepts linking drainage basin characteristics, stream behavior, and management of watersheds are deduced from field data and observations. An electrical analogy of a watershed clarifies definitions and broadens understanding of this complex natural resource. The three basic principles deal with (1) the interrelationships of watershed morphology, constitution, and appearance; (2) the nature of the control man can exert over runoff-influencing forces, and (3) the efficiency of watershed management efforts. Recognition of these principles can assist educators, managers, planners and researchers to more fully inform students and to more effectively guide and evaluate management decisions. 相似文献
113.
Problem: Safety climate refers to the degree to which employees believe true priority is given to organizational safety performance, and its measurement is thought to provide an “early warning” of potential safety system failure(s). However, researchers have struggled over the last 25 years to find empirical evidence to demonstrate actual links between safety climate and safety performance.Method: A safety climate measure was distributed to manufacturing employees at the beginning of a behavioral safety initiative and redistributed one year later.Results: Multiple regression analysis demonstrated that perceptions of the importance of safety training were predictive of actual levels of safety behavior. The results also demonstrate that the magnitude of change in perceptual safety climate scores will not necessarily match actual changes (r=0.56, n.s.) in employee's safety behavior.Discussion: This study obtained empirical links between safety climate scores and actual safety behavior. Confirming and contradicting findings within the extant safety climate literature, the results strongly suggest that the hypothesized climate-behavior-accident path is not as clear cut as commonly assumed.Summary: A statistical link between safety climate perceptions and safety behavior will be obtained when sufficient behavioral data is collected.Impact on Industry: The study further supports the use of safety climate measures as useful diagnostic tools in ascertaining employee's perceptions of the way that safety is being operationalized. 相似文献
114.
回燃及其对腔室火灾过程的影响 总被引:8,自引:0,他引:8
从火灾中的两种特殊火行为-轰燃和回燃的发生机理出发,着重讨论了回燃在整个火灾过程中的作用以及回燃对轰燃的影响。结果表明,由于回燃和轰燃同为火灾全过程中的分过程,并且由于二者发生机理的相似性,因而,它们可以建立联系。当具备合适的热解产物浓度时,回燃过程可以使火灾系统的状态突变到完全发展状态,即引发轰燃。 相似文献
115.
Shue Tuck Wong 《Journal of the American Water Resources Association》1979,15(2):396-403
ABSTRACT: Human behavior and response towards storm hazard are examined in this study. One-hundred and twenty flood victims in West Vancouver, British Columbia, were administered a sentence completion test to ascertain how these victims behaved and responded to the flash flood of July 12, 1972. The sentence completion test consisted of 11 sentence stems. Seven of these dealt with the respondent's behavior toward the storm experience, and four with the issue of internal vs. external locus of control. Completions of the seven sentence stems at three time situations showed that West Vancouverites expressed the normal reactions of fear and anxiety before the storm; showed negative emotions during the storm; and displayed a feeling of mutual cooperation after the storm. Completions of the remaining four sentence stems revealed that West Vancouverites emphasized the importance of internal factors, viz., autonomy, drive and hard work, in controlling their lives. They recognized God as a benevolent - protective and almighty - powerful figure. Forty percent of the respondents did not believe in luck, while 8 percent regarded it as important in their lives. One might conclude that West Vancouverites could cope with natural hazardous threats better than those who rely on external factors in directing their lives. 相似文献
116.
William E. Hammitt 《Environmental management》1980,4(5):425-431
Bogs are of interest to outdoor recreationists, but little information exists concerning how recreation resource managers might manage these areas to enhance visitor benefits. This study evaluates bog visitor characteristics and experiences, visual preferences, and reasons for visiting. Implications for recreational resource management of bogs include the location and design of boardwalk trails and management of understory vegetation to meet the visual preferences and motives of bog visitors. 相似文献
117.
Daniel A. Cincotta Jay R. Stauffer Charles H. Hocutt 《Journal of the American Water Resources Association》1982,18(3):437-450
ABSTRACT: The applicability of the U.S Environmental Protection Agency's (USEPA) water temperature criteria in evaluating the impact of a thermal discharge from the P. H. Glatfelter Paper Company, Spring Grove, Pennsylvania, is analyzed. A review of the literature relative to 11 temperature Criteria was conducted for six fish species designated by the USEPA as “representative important species” (RIS) of the West Branch Codorus Creek, Susquehanna River drainage. The species were: Notemigonus crysolcucas (golden shiner), Notropis analostanus (satinfin shiner), Rhinichthys atratulus (blacknose dace), Catostomus comme-soni (white sucker), Lepomis gibbosus (pumpkinseed). and Micropterous salmoides (largemouth bass). It was found that by applying only USEPA suggested criteria that a complete evaluation was not satisfactory. Temperature behavior data, specifically preference and avoidance information, coupled with field sampliug was needed to properly assess the effects of the thermal effluent. The final analysis indicated that the thermal discharge of the paper company should have minimal effect on the fish community of Codorus Creek. 相似文献
118.
A time‐lagged investigation of the impact of coworker behavior on the effects of demographic dissimilarity 下载免费PDF全文
Although it is clear that coworker absenteeism, tardiness, and turnover can influence an employee's actions, scholars have yet to consider the impact of relational demography on the adoption of these behavioral norms. Inspired by social identity, situational strength, and attraction‐selection‐attrition theories, we proposed that individuals who differ from their coworkers in age, sex, or racioethnicity would feel threatened by their outnumbered status and subsequently motivated to be absent, tardy, or more likely to turnover. However, we expected coworker withdrawal behavior to moderate whether or not dissimilar personnel act on these desires. Results from hierarchical multilevel modeling analyses of data from 470 U.S. call center workers nested in 51 work groups revealed that racioethnic dissimilarity was positively related to time‐lagged changes in absenteeism and tardiness as well as heightened turnover likelihood. These effects emerged only among employees whose coworkers engaged in greater withdrawal behavior. Importantly, racioethnically dissimilar employees working in more permissive climates (i.e., those with high levels of coworker absenteeism, tardiness, or turnover) exhibited the greatest increases in absenteeism and tardiness over three months and had the highest supervisor‐rated turnover likelihood. Implications for diversity management are discussed. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
119.
Perceived prosocial impact,perceived situational constraints,and proactive work behavior: Looking at two distinct affective pathways 下载免费PDF全文
This paper examines the role of affect as a linking mechanism between experiences at work (perceived prosocial impact and situational constraints) and two distinct components of proactive work behavior (issue identification and implementation). Based on a dual‐tuning perspective, we argue that both positive affect and negative affect can be beneficial for proactive work behavior. Multi‐level path analysis using daily‐survey data from 153 employees showed that perceived prosocial impact predicted positive affect and that situational constraints as a typical hindrance stressor predicted negative affect. Negative affect, in turn, predicted issue identification, and positive affect predicted implementation. Overall, our study suggests that both positive and negative affects can be valuable in the organizational context by contributing to distinct components of proactive behavior. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
120.
Objectives: Engaging in active transport modes (especially walking) is a healthy and environmentally friendly alternative to driving and may be particularly beneficial for older adults. However, older adults are a vulnerable group: they are at higher risk of injury compared with younger adults, mainly due to frailty and may be at increased risk of collision due to the effects of age on sensory, cognitive, and motor abilities. Moreover, our population is aging, and there is a trend for the current cohort of older adults to maintain mobility later in life compared with previous cohorts. Though these trends have serious implications for transport policy and safety, little is known about the contributing factors and injury outcomes of pedestrian collision. Further, previous research generally considers the older population as a homogeneous group and rarely considers the increased risks associated with continued ageing.Method: Collision characteristics and injury outcomes for 2 subgroups of older pedestrians (65–74 years and 75+ years) were examined by extracting data from the state police–reported crash dataset and hospital admission/emergency department presentation data over the 10-year period between 2003 and 2012. Variables identified for analysis included pedestrian characteristics (age, gender, activity, etc.), crash location and type, injury characteristics and severity, and duration of hospital stay. A spatial analysis of crash locations was also undertaken to identify collision clusters and the contribution of environmental features on collision and injury risk.Results: Adults over 65 years were involved in 21% of all pedestrian collisions. A high fatality rate was found among older adults, particularly for those aged 75 years and older: this group had 3.2 deaths per 100,000 population, compared to a rate of 1.3 for 65- to 74-year-olds and 0.7 for adults below 65 years of age. Older pedestrian injuries were most likely to occur while crossing the carriageway; they were also more likely to be injured in parking lots, at driveway intersections, and on sidewalks compared to younger cohorts. Spatial analyses revealed older pedestrian crash clusters on arterial roads in urban shopping precincts. Significantly higher rates of hospital admissions were found for pedestrians over the age of 75 years and for abdominal, head, and neck injuries; conversely, older adults were underrepresented in emergency department presentations (mainly lower and upper extremity injuries), suggesting an increased severity associated with older pedestrian injuries. Average length of hospital stay also increased with increasing age.Conclusion: This analysis revealed age differences in collision risk and injury outcomes among older adults and that aggregate analysis of older pedestrians can distort the significance of risk factors associated with older pedestrian injuries. These findings have implications that extend to the development of engineering, behavioral, and enforcement countermeasures to address the problems faced by the oldest pedestrians and reduce collision risk and improve injury outcomes. 相似文献