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111.
The study shows that, for a sample of 818 industrial workers, work role centrality (WRC) is positively related to task autonomy and to organizational conditions of sector of ownership, unit-type of production system, and production stability; it is also weakly related to the orientations of production managers concerning the sharing of information, general supervision and granting autonomy. The task autonomy - work role centrality relationship is maintained beyond other organizational conditions, but the effects of managerial orientations are attenuated by task autonomy and by organizational conditions. Situational conditions such as production system and stability, managerial orientations and task autonomy add to the variance of WRC explained by personal attributes of gender, education and job training, and by the outcome of job satisfaction, and a combined model of both types of variables is the most efficient. Generally, work role centrality is found to be a fairly sensitive response to the work situation, but it is suggested that perceptual and attitudinal data be added to the explanatory model. 相似文献
112.
Robert C. Rychert Gordon R. Stephenson 《Journal of the American Water Resources Association》1986,22(1):39-42
ABSTRACT: Lactose-negative Escherichia coil from cattle feces appeared as yellow, atypical colonies on m-FC medium plates with water samples from rangeland streams. The lactose-negative E. coil may impact stream water quality analyses if infrequent samples are collected; are less antibiotic resistant than the lactose-positive E. coili isolated from rangeland streams; and are colicinogenic toward all the laboratory strains of E. coil examined and toward 61 percent of the lactose-positive E. coil rangeland-stream isolates that were tested. This latter result could explain the potentially low degree of antibiotic resistance transfer from lactose-positive to lactose-negative E. coil. In addition, the colicinogenicity of the lactose-negative E. coil may interfere with microbiological water quality analyses that depend upon lactose fernientations with mixed populations of coliforms. 相似文献
113.
Fishermen were aggregated into high-, mid-, and low-consumptive groups according to the importance they placed on catching fish. Analysis of variance indicated that each consumptive group was unique in the importance it placed on other fish-related variables. Low-consumptive fishermen rated most other aspects of the fishing experience, such as interacting with nature, relaxation, and escaping the daily routine, more important than did high-consumptive fishermen. Low-consumptive fishermen also fished more frequently and were generally more satisfied with their most recent fishing trip than were high-consumptive-oriented fishermen. The three groups can be viewed as different fishing constituencies. By understanding their characteristics, we can gain additional insights into the impacts of management decisions on recreational fishermen and their experiences. 相似文献
114.
Robert J. Langridge Bryan D. MacGregor 《Journal of Environmental Planning and Management》1986,29(1):19-22
This study analyses the behaviour of high technology and new firms in the Newbury District of Berkshire in terms of employment, location, genealogy, and local economic impact. It finds that encouraged by good communications networks and a ‘resident electronics establishment’, the direct, as opposed to the indirect, employment consequences are generally encouraging, but not widely replicable. Moreover, the general picture of employment growth masks important differences in labour demand across occupations, particularly with respect to ‘traditional male’ skilled manual workers. 相似文献
115.
Robert G. Bailey 《Environmental management》1988,12(1):11-17
As part of the planning process, maps of natural factors are often superimposed in order to identify areas which are suitable or unsuitable for a particular type of resource management. Overlay maps may also be used to identify analysis areas for predictive modeling of resource productivity and ecological response to management. Current interest in applying computer-assisted mapping technology to making overlay maps is drawing attention to geographic information systems for this purpose. The resultant maps, however, may be so inaccurate or unable to capture significant units of productivity and ecological response that they could lead to imperfect or false conclusions. Recommendations are made on how to proceed in light of these problems. 相似文献
116.
117.
The objective of the project was to identify all hazardous waste sites in Burlington County, New Jersey that could be detected on existing, medium-scale aerial photographs of the county. The complete set of over 1000 black- and-white stereopairs at a scale of 1:12,000 was carefully examined for initial identification of possible sites. All suspicious sites were examined again on color transparencies of the county at the same 1:12,000 scale. Out of the 1094 black- and-white photos, 250 required further checking on color transparencies using a zoom stereoscope. This examination resulted in a final identification of 67 sites, the locations of which were delineated on 1:24,000 USGS maps. The use of air photo interpretation techniques provided an effective procedure for identifying waste sites quickly as well as providing a useful demonstration program for county and state officials. 相似文献
118.
ABSTRACT: The relative abundance of small mammals in five forest land cover types on the upper Coastal Plain of north Mississippi was determined. Burrowing mammals accounted for one-half of the total captures; one shrew species that accounted for over one-fourth of the total captures had a strong affinity for well-stocked pine plantations. The opportunity for detention and retention of rainfall was enhanced by burrowing activity. Reductions of stormflow volumes 12 to 15 years after replacing poor quality, upland hardwoods with loblolly pine were only partially explained by increased interception of rainfall; much of the residual reductions are postulated to be due to small mammal burrows. Small mammal activity deserves further study as an important aspect of forest land hydrology. 相似文献
119.
Robert M. Hirsch 《Journal of the American Water Resources Association》1988,24(3):493-503
ABSTRACT: This paper addresses two components of the problem of estimating the magnitude of step trends in surface water quality. The first is finding a robust estimator appropriate to the data characteristics expected in water-quality time series. The Hodges-Lehmann class of estimators is found to be robust in comparison to other nonparametric and moment-based estimators. A seasonal Hodges-Lehmann estimator is developed and shown to have desirable properties. Second, the effectiveness of various sampling strategies are examined using Monte Carlo simulation coupled with application of this estimator. The simulation is based on a large set of total phosphorus data from the Potomac River. To assure that the simulated records have realistic properties, the data are modeled in a multiplicative fashion incorporating flow, hysteresis, seasonal, and noise components. The results demonstrate the importance of balancing the length of the two sampling periods and balancing the number of data values between the two periods. The inefficiency of sampling at frequencies much in excess of 12 samples per year is demonstrated. Rotational sampling designs are discussed, and efficient designs, at least for this river and constituent, are shown to involve more than one year of active sampling at frequencies of about 12 per year. 相似文献
120.
Robert Leconte Rangesan Narayanan Trevor C. Hughes 《Journal of the American Water Resources Association》1988,24(2):247-253
ABSTRACT: A general methodology to study the economics of dual water systems (defined here as a separate distribution system for untreated low quality local surface Water for outdoor municipal water supply) is summarized and the application of the method to a rapidly growing city is presented. In the first step, a cost-benefit criterion for evaluating dual systems is developed. The criterion is then extended to a dynamic case where the population to be served increases with time and where the dual system is allowed to expand. The optimal investment time to introduce the dual water supply project is obtained by maximizing social welfare. The model is applied to the city of West Jordan, Utah, where a dual system is currently being proposed. Model results indicate that for the city as a whole dual supply is not economically feasible. However, when the model is applied to a part of the city, it is found feasible and the optimal time to initiate the project would be in the year 1989. 相似文献