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681.
Competition between individuals permeates people's lives as they strive for limited resources, services, and status. However, research on competition and competitiveness in organizations is limited despite its relevance to relational dynamics (e.g., rivalry), individual differences (e.g., traits and gender), social factors (e.g., competitive climate), and organizational outcomes (e.g., work performance and unethical behavior). In this article, we propose a multilevel model of competition and competitiveness that includes the individual, the group, and the situation. By providing a holistic overview of research across a broad array of disciplines, we organize the field and create a usable framework to advance knowledge of competition and competitiveness. In doing so, we identify what we know, what we still need to discover, and provide direction for future research. The article closes with an assessment of methods and measures used in studying competition. In conclusion, this review establishes a multilevel and integrative structure that incorporates individual and team competitiveness with competitive situations that prompt competitive processes and important organizational outcomes. 相似文献
682.
C. W. Johnson 《Safety Science》1996,22(1-3)
Introducing safety devices does not always reduce the frequency of accidents. Operators adjust their response to technological improvements. Protection mechanisms may be used to support “unsafe” working practices so that the net risk of failure remains unchanged or may even rise. Regulatory bodies have reacted against this risk compensation. Rules and procedures have been imposed upon the day-to-day operation of protection equipment. Unfortunately, these constraints often fail to preserve the safety of an application. Inattention, fatigue, poor training and willful neglect can lead to rules and guidelines being ignored. In this paper alternative means of reducing threats posed by risk compensation are explored. In particular, it is argued that designers must exploit an integrated approach to the development of high-risk applications. By this we mean that both human factors and systems engineering must be recruited to support the development of protection equipment. 相似文献
683.
Philip Bedient Alejandro Flores Steven Johnson Plato Pappas 《Journal of the American Water Resources Association》1985,21(4):543-552
ABSTRACT: The Woodlands, a totally planned community north of Houston, Texas, was studied in detail in an effort to develop a master drainage plan which minimizes adverse impact on the 100-year floodplain. A total of 40 HEC-1 and HEC-2 computer runs were made to evaluate various development, channelization, and reservoir storage options. 相似文献
684.
William K. Johnson Darryl W. Davis 《Journal of the American Water Resources Association》1984,20(1):15-22
ABSTRACT: The Hydrologic Engineering Center, Corps of Engineers, has been engaged in research, training, and project assistance in non-structural flood control planning for Corps offices across the United States since 1975. Lessons learned from this experience deal with the role of nonstructural measures in flood plain management, the role of creativity in analysis, the role of analysis, and tools for analysis. The role of nonstructural measures in flood control planning depends upon the scale of the problem, the nature of the measure, the degree of protection desired, and whether damage is to existing or future property. An earnest seeking for nonstructural opportunities, a field presence for their formulation, and compatbility with local infrastructure plans are prerequisite to creative use of nonstructural measures. Analysis is a necessary complement of creativity. Several tools for nonstructural analysis have been developed and applied to flood problems involving several hundred and several thousand structures. 相似文献
685.
Steven W. Effler Mary Gail Perkins Harry Greer David L. Johnson 《Journal of the American Water Resources Association》1987,23(2):189-196
ABSTRACT: The effects “whiting” (CaCO3 precipitate) had on the optical properties and turbidity of the epilimnion of Owasco Lake, New York, were studied during the summer of 1985. Turbidity was partitioned according to “whiting” and non-“whiting” components utilizing a simple acidification procedure. Diffuse light attenuation was partitioned according to the attenuating processes of absorption and scattering. “Whiting” was present most of the summer. Two major “whiting” events occurred that caused major increases in turbidity and the attenuation of light. “Whiting” was the principle regulator of turbidity during the study; it caused increases in light attenuation by increasing light scattering. “Whiting” events can easily be mistaken by the public for phytoplankton blooms. 相似文献
686.
William K. Johnson 《Journal of the American Water Resources Association》1974,10(3):478-485
ABSTRACT: It is the thesis of this paper that plan formulation is both art and science, and that to improve formulation, to develop better alternatives, the planner needs to both improve his creative capability and to think more systematically. Research into creativity by psychologist and social scientist has identified four aspects of creativity: the creative process, the creative product, the creative person, the creative situation. A review of research results on each aspect suggests several ways in which planners can improve the creative dimension of plan formulation. To improve the rational aspects of plan formulation a way of thinking is presented in the form of a conceptual model to assist the planner in systematically developing a broader range of plans. The major components are inventory, forecast and synthesis. The model utilizes the concept of a production function to provide information about the resource, management practices and its use. 相似文献
687.
688.
Jeffrey Lee Robbins Church Duane Lammers Leon Liegel Mark Johnson Deborah Coffey Richard Holdren Donald Stevens Robert Turner Louis Blume 《Environmental management》1989,13(1):95-108
Through the Direct/Delayed Response Project (DDRP), the United States Environmental Protection Agency is attempting to assess the risk to surface waters from acidic deposition in three regions of the eastern United States: the Northeast Region, the Southern Blue Ridge Province, and the Mid-Appalachian Region. The central policy question being addressed by the DDRP is: Within the regions of concern, how many surface water systems (lakes, streams) will become acidic due to current or altered levels of acidic sulfur deposition, and on what time scales? The approach taken by the DDRP is to select a statistically representative set of watersheds in each region of concern and to project the future response of each watershed to various assumed levels of acidic deposition. The probability structure will then be used to extrapolate the watershed-specific results to each region. The data will be used also for statistical investigation of hypothesized relationships between current surface water chemistry and watershed characteristics. Because the needed terrestrial data base was not available, regional watershed surveys were conducted to meet the specific data needs of the DDRP. Maps (1∶24,000) of soils, vegetation, land use, depth to bedrock, and bedrock geology were made for each watershed. The soils were grouped into sampling classes based on their hypothesized response to acidic deposition. Randomized sampling of these classes provided regional means and variances of soil properties that can be applied to individual watersheds. Because of DDRP's need for consistency within and among regions, unique quality control/quality assurance activities were developed and implemented. After verification and validation, the DDRP data base will be made publicly available. This will be a unique and useful resource for others investigating watershed relationships on a regional scale. The results of these surveys and the conclusions of the DDRP will be presented in several future papers. The current paper gives an overview of the context, rationale, logistical considerations, and implementation of these surveys, with special emphasis on the field activities of watershed mapping and soil sampling. This discussion should be useful to those planning, implementing, and managing survey activities in support of regional assessments of other environmental concerns, who are likely to face similar choices and constraints. 相似文献
689.
Charles W. Slaughter Charles H. Racine Donald A. Walker Larry A. Johnson Gunars Abele 《Environmental management》1990,14(1):63-72
Use of off-road vehicles (ORVs) in permafrost-affected terrain of Alaska has increased sharply over the past two decades.
Until the early 1960s, most ORV use was by industry or government, which employed heavy vehicles such as industrial tractors
and tracked carriers. Smaller, commercial ORVs became available in the 1960s, with the variety and number in use rapidly increasing.
Wheeled and tracked ORVs, many used exclusively for recreation or subsistence harvesting by individuals, are now ubiquitous
in Alaska. This increased use has led to concern over the cumulative effects of such vehicles on vegetation, soils, and environmental
variables including off-site values.
Factors affecting impact and subsequent restoration include specific environmental setting; vegetation; presence and ice content
of permafrost; microtopography; vehicle design, weight, and ground pressure; traffic frequency; season of traffic; and individual
operator practices. Approaches for mitigating adverse effects of ORVs include regulation and zoning, terrain analysis and
sensitivity mapping, route selection, surface protection, and operator training.
We regret the untimely death of Gunars Abele on August 27, 1989; he was a valued colleague and good friend. 相似文献
690.
Ted M. Sparr 《Journal of the American Water Resources Association》1979,15(3):853-860
ABSTRACT: This paper describes the verification of the QUAL-1 mass transport model for the lower Mississippi River between St. Francisville and Point a la Hache using dye studies conducted by the U. S. Geological Survey. QUAL-1 is a one-dimensional steady-state model for rivers and is capable of predicting longitudinal profiles of soluble materials entering rivers from point sources. Both conservative and nonconservative parameters of water quality can be considered. The major problems surmounted were the determination of a diffusion coefficient and the use of transient data to verify a steady state model. 相似文献