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921.
We observe the behavior of 37 authors of shared (i.e., non‐commercial) software for the Apple Newton in terms of multiplex commitment (committed to multiple related targets) and the helping behaviors directed at these multiple related targets. The behavior of these shared software authors show a pattern of commitment to related targets consistent with our expectations of multiplex commitment and relationships to two helping behaviors (the number of shared software programs produced, and the degree of sacrifice expected with that shared software). The related targets of commitment were the users of the software, other shared software authors, and the newsgroup that served as the electronic social exchange system, but not the FTP site that enabled the exchange or the Listserv that served as an additional electronic social exchange system. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
922.
This study examines the relationship between organizational commitment and supervisory commitment (commitment to supervisor) in terms of their effects on employee outcomes in the Chinese context. Based on the principle of compatibility, we hypothesized that organizational commitment and supervisory commitment served as logical mediators (global hypothesis and proximal hypothesis) for predicting organization‐relevant and leader‐relevant outcomes respectively. Moreover, because of the impact of personalism in Chinese culture, we predicted that supervisory commitment also significantly influenced organization‐relevant outcomes, in addition to its effect on leader‐relevant outcomes. Two separate questionnaires were administered to 538 subordinates and their supervisors in Taiwanese companies. Structural equation modeling and hierarchical block regression analysis shows that the principle of compatibility and personalism can explain the proposed relationship in this study. Implications and research directions are discussed in light of Chinese culture for future investigation into organizational commitment and supervisory commitment. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
923.
An important goal of biological inventories is to provide information for environmental assessments of development projects and biodiversity conservation. Likewise, computer data bases have been proposed for efficient compilation and management of biological information. However, the attributes of biological inventories and computer data bases have not been examined with respect to environmental assessments. This article presents a case study in Mexico to analyze the current limitations of biological inventories for successful environmental assessments and biodiversity conservation in developing countries. Results demonstrate that, considering the objectives of environmental assessments and information constraints, computerized biological inventories should be assembled with a minimum of record fields: taxonomic data and georeferenced collection localities. Furthermore, it is proposed that environmental assessments should become a feedback to biological inventories and an important financial support to universities and research institutions in developing countries.  相似文献   
924.
Environmental planners and managers may want to do their work without political interference, using rational and objective knowledge only. They may also want to serve the common good, be accountable and encourage public participation. This paper explores the tensions between the two approaches and argues that a great deal of politics goes into the very definition and selection of what is considered rational and objective. Too often policy‐makers claim to rely exclusively on objective scientific or economic knowledge, while ignoring other forms of knowledge which may be as essential for the solution or management of the problem. Difficult choices have to be made, and it may well be the political scientist, sociologist or psychologist who can help. Expertise has its own interest in the policy process—it is mainly concerned with perpetuating itself and the search for more knowledge. To be effective as well as rational, environmental managers need to be aware of a broad range of useful knowledge, as well as suspicious of claims that promise too much. They need to be in open communication with society, and this may well require institutional reform.  相似文献   
925.
The British Government is proposing a new system of single‐tier development plans for England and Wales, with clear implications for the strategic level of planning. This paper considers a proposal by the Committee of Inquiry into Town and Country Planning set up by the Nuffield Foundation, for a revised strategic planning network which includes a ‘local strategy’. The paper considers the lessons to be drawn from the use of regional reports in Scotland since the early 1970s and concludes on a note of caution for the Government's proposals.  相似文献   
926.
Stochastic modeling of vector hydrologic sequences is examined with a general class of space-time autoregressive integrated moving average (STARIMA) models. The models describe spatial and temporal autocorrelatjon, through dependent variables lagged both in space and time. The model structures incorporate a hierarchical ordering scheme to map the vector of observations into a network configuration. The neighboring structure used introduces a physical/geographical hierarchy to enable the model identification procedures to assist in determining appropriate correlative relationships. The three-stage iterative space-time model building procedure is illustrated using average monthly streamfiow data for a four-station network of the Southeastern Hydropower System.  相似文献   
927.
One of the problems which often arises in engineering hydrology is to estimate data at a given site because either the data are missing or the site is ungaged. Such estimates can be made by spatial interpolation of data available at other sites. A number of spatial interpolation techniques are available today with varying degrees of complexity. It is the intent of this paper to compare the applicability of various proposed interpolation techniques for estimating annual precipitation at selected sites. The interpolation techniques analyzed include the commonly used Thiessen polygon, the classical polynomial interpolation by least-squares or Lagrange approach, the inverse distance technique, the multiquadric interpolation, the optimal interpolation and the Kriging technique. Thirty years of annual precipitation data at 29 stations located in the Region II of the North Central continental United States have been used for this study. The comparison is based on the error of estimates obtained at five selected sites. Results indicate that the Kriging and optimal interpolation techniques are superior to the other techniques. However, the multiquadric technique is almost as good as those two. The inverse distance interpolation and the Thiessen polygon gave fairly satisfactory results while the polynomial interpolation did not produce good results.  相似文献   
928.
ABSTRACT: Alternative approaches suggested for modeling multiseries of water resources systems are reviewed and compared. Most approaches fall within the general framework of multivariate ARMA models. Formal modeling procedures suggest a three-stage iterative process, namely: model identification, parameter estimation and diagnostic checks. Although a number of statistical tools are already available to follow such modeling process, in general, it is not an easy task, especially if high order vector ARMA models are used. However, simpler ARMA models such as the contemporaneous and the transfer-function models may be sufficient for most applications in water resources. Two examples of modeling bivariate and trivariate streamflow series are included. Alternative modeling procedures are used and compared by using data generation techniques. The results obtained suggest that low order models, as well as contemporaneous ARMA models, reproduce quite well the main statistical characteristics of the time series analyzed. It is assumed that the same conclusions apply for most water resources time series.  相似文献   
929.
New forms of careers have received increased attention in contemporary organizational research. A prominent focus in this research has been whether and how, in an increasingly unpredictable career environment, individuals are taking responsibility for their own career development. The implication is that career is becoming less central to organizational management practices. At the same time there is evidence that organizational changes typically described in this literature (such as delayering the organization in a quest for flexibility) have had a negative impact on career progress, resulting in resistance to change. The implication here is that career concerns are more central to organizational management practices. This in‐depth qualitative case study examines whether individuals do in fact take more responsibility for their career development during times of organizational change. We also examine whether this does indeed mean that the organization takes less responsibility for career management. Our data indicate that individuals are, in fact, taking more responsibility for their own careers. At the same time we found that the organization in our case study also became more actively involved in career development and management. However, this active approach did not resemble traditional top‐down career management and development. To us, the pattern of organizational and individual career development actions appear to constitute a kind of ‘organizational dance,’ a highly interactive mutual influence process, in which both parties are at once the agent and the target of career influence. Strengths and limitations of the study are discussed, as are directions for future research. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
930.
Soil moisture content and temperature in a contaminated soil biopile equipped with immobilized microbe bioreactors (IMBRs) were optimized during ex situ bioremediation at a creosote‐contaminated Superfund site. Efficiency of remediation during warm summer months without soil‐temperature and moisture optimization was compared with that of cold winter months when corrective measures were applied. Significant reduction (35 percent) in total polycyclic aromatic hydrocarbons (PAHs) was observed, compared to 3.97 percent without corrective measures (p < 0.05). Kinetic rates (KRs) for total PAH removal were significantly enhanced from 3.93 to 50.95 mg/kg/day. KRs for removal of high molecular mass four‐to‐six‐ring PAHs were also significantly enhanced from 70.29 mg/kg/day to 97.45 mg/kg/day ( p < 0.05). Bioremediation of two‐ and three‐ring PAHs increased significantly from 15 percent to 40 percent. Benzo[a]pyrene toxicity equivalent mass (BaPequiv) was significantly reduced by 48 percent with KR of 0.47 mg/kg/day as compared to 22 percent with KR of 0.14 mg/kg/day (p < 0.05). Soil moisture content was enhanced from 15.7 percent to 41.4 percent. © 2007 Wiley Periodicals, Inc.  相似文献   
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