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711.
ABSTRACT: Genetic programming (GP), a relatively new evolutionary technique, is demonstrated in this study to evolve codes for the solution of problems. First, a simple example in the area of symbolic regression is considered. GP is then applied to real‐time runoff forecasting for the Orgeval catchment in France. In this study, GP functions as an error updating scheme to complement a rainfall‐runoff model, MIKE11/NAM. Hourly runoff forecasts of different updating intervals are performed for forecast horizons of up to nine hours. The results show that the proposed updating scheme is able to predict the runoff quite accurately for all updating intervals considered and particularly for updating intervals not exceeding the time of concentration of the catchment. The results are also compared with those of an earlier study, by the World Meteorological Organization, in which autoregression and Kalman filter were used as the updating methods. Comparisons show that GP is a better updating tool for real‐time flow forecasting. Another important finding from this study is that nondimensionalizing the variables enhances the symbolic regression process significantly.  相似文献   
712.
Two studies were used to examine the moderating effect of gender on the justice–outcome relationships. Contrary to hypothesis, gender moderates the relationship between distributive justice and trust in supervisor in sample 1. It is possible that women are concentrating more on distributive issues rather than procedural justice issues in order to address past pay discrepancies. Further, gender did not moderate any other justice–outcome relationships. These results may indicate a recent trend toward work value similarity and narrowing of gender differences. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
713.
This article examines how small and medium enterprises (SMEs) can improve their capital investment decisionmaking process for both environmental and general capital projects. It proposes a framework that helps integrate environmental impacts into capital investment decisions, while recognizing SMEs' specific management practices, unique culture, and constraints. The framework presented here is also applicable to independent strategic business units of larger organizations where the capital investment decision process is decentralized. ©2000 John Wiley & Sons, Inc.  相似文献   
714.
The objective of the present research is to compare fecal coliform removal from two different sand column systems treating septic tank effluent over a range of hydraulic loading rates. Drain time measurements were performed to compare the hydraulic characteristic of the column systems at different hydraulic loading rates. Biochemical oxygen demand (BOD), total suspended solids (TSS), and pH were also measured for the septic tank effluent. A removal of the order of 99% for fecal coliform, TSS, and BOD in column effluent was achieved using the sand filter columns. The ‘break‐in’ period for determining the effectiveness of the sand filter columns is also discussed.  相似文献   
715.
Concerns about the social consequences of conservation have spurred increased attention the monitoring and evaluation of the social impacts of conservation projects. This has resulted in a growing body of research that demonstrates how conservation can produce both positive and negative social, economic, cultural, health, and governance consequences for local communities. Yet, the results of social monitoring efforts are seldom applied to adaptively manage conservation projects. Greater attention is needed to incorporating the results of social impact assessments in long‐term conservation management to minimize negative social consequences and maximize social benefits. We bring together insights from social impact assessment, adaptive management, social learning, knowledge coproduction, cross‐scale governance, and environmental planning to propose a definition and framework for adaptive social impact management (ASIM). We define ASIM as the cyclical process of monitoring and adaptively managing social impacts over the life‐span of an initiative through the 4 stages of profiling, learning, planning, and implementing. We outline 14 steps associated with the 4 stages of the ASIM cycle and provide guidance and potential methods for social‐indicator development, predictive assessments of social impacts, monitoring and evaluation, communication of results, and identification and prioritization of management responses. Successful ASIM will be aided by engaging with best practices – including local engagement and collaboration in the process, transparent communication of results to stakeholders, collective deliberation on and choice of interventions, documentation of shared learning at the site level, and the scaling up of insights to inform higher‐level conservation policies‐to increase accountability, trust, and perceived legitimacy among stakeholders. The ASIM process is broadly applicable to conservation, environmental management, and development initiatives at various scales and in different contexts.  相似文献   
716.
Settleable particulate matter (SPM) is an atmospheric pollutant harmful to human health and the environment in high concentrations. Despite this fact, no up‐to‐date information on SPM levels exists for the capital of Chile, Santiago (7 million inhabitants). To address this knowledge gap, SPM sedimentation rates, including soluble and insoluble components, were measured at three different urban sites from July to November of 2016. We compare the measurements with ambient and meteorological information, as well as urban typology settings. Our results indicate SPM deposition rates between 2.5 and 3.9 g/(m2·30 days). Only one site exceeded the national limit of 4.5 g/(m2·30 days), but we found an increasing trend in all three sites. SPM and its insoluble sedimentation rates increased during warm and dry months and presented significant correlations with meteorological parameters. The highest sedimentation rates were measured at the location with the least permeable surfaces and the lowest green spaces, while the lowest sedimentation rates were found in the sites with abundant green spaces and permeable soil. No significant differences were detected in the soluble components. Our results suggest that SPM levels in Santiago are close to the national limit and may increase with climate change and urban expansion.  相似文献   
717.
This meta‐analysis investigates the direction and strength of the relationship between diversity in culturally diverse teams and team creativity/innovation. We distinguish the effects of two diversity levels (i.e., surface level vs. deep level) in culturally diverse teams and examine the moderators suggested by the socio‐technical systems framework (i.e., team virtuality and task characteristics in terms of task interdependence, complexity, and intellectiveness). Surface‐level diversity in culturally diverse teams is not related to team creativity/innovation, whereas deep‐level diversity in culturally diverse teams is positively related to team creativity/innovation. Moreover, surface‐level diversity in culturally diverse teams and team creativity/innovation are negatively related for simple tasks but unrelated for complex tasks. Deep‐level diversity in culturally diverse teams and team creativity/innovation is positively related for collocated teams and interdependent tasks but unrelated for noncollocated teams and independent tasks. We discuss the theoretical and practical implications.  相似文献   
718.
In many cases, the first step in large‐carnivore management is to obtain objective, reliable, and cost‐effective estimates of population parameters through procedures that are reproducible over time. However, monitoring predators over large areas is difficult, and the data have a high level of uncertainty. We devised a practical multimethod and multistate modeling approach based on Bayesian hierarchical‐site‐occupancy models that combined multiple survey methods to estimate different population states for use in monitoring large predators at a regional scale. We used wolves (Canis lupus) as our model species and generated reliable estimates of the number of sites with wolf reproduction (presence of pups). We used 2 wolf data sets from Spain (Western Galicia in 2013 and Asturias in 2004) to test the approach. Based on howling surveys, the naïve estimation (i.e., estimate based only on observations) of the number of sites with reproduction was 9 and 25 sites in Western Galicia and Asturias, respectively. Our model showed 33.4 (SD 9.6) and 34.4 (3.9) sites with wolf reproduction, respectively. The number of occupied sites with wolf reproduction was 0.67 (SD 0.19) and 0.76 (0.11), respectively. This approach can be used to design more cost‐effective monitoring programs (i.e., to define the sampling effort needed per site). Our approach should inspire well‐coordinated surveys across multiple administrative borders and populations and lead to improved decision making for management of large carnivores on a landscape level. The use of this Bayesian framework provides a simple way to visualize the degree of uncertainty around population‐parameter estimates and thus provides managers and stakeholders an intuitive approach to interpreting monitoring results. Our approach can be widely applied to large spatial scales in wildlife monitoring where detection probabilities differ between population states and where several methods are being used to estimate different population parameters.  相似文献   
719.
Most examples that support the substitution‐habitat hypothesis (human‐made habitats act as substitutes of original habitat) deal with birds and mammals. We tested this hypothesis in 14 amphibians by using percentage occupancy as a proxy of habitat quality (i.e., higher occupancy percentages indicate higher quality). We classified water body types as original habitat (no or little human influence) depending on anatomical, behavioral, or physiological adaptations of each amphibian species. Ten species had relatively high probabilities (0.16–0.28) of occurrence in original habitat, moderate probability of occurrence in substitution habitats (0.11–0.14), and low probability of occurrence in refuge habitats (0.05–0.08). Thus, the substitution–habitat hypothesis only partially applies to amphibians because the low occupancy of refuges could be due to the negligible human persecution of this group (indicating good conservation status). However, low occupancy of refuges could also be due to low tolerance of refuge conditions, which could have led to selective extinction or colonization problems due to poor dispersal capabilities. That original habitats had the highest probabilities of occupancy suggests amphibians have a good conservation status in the region. They also appeared highly adaptable to anthropogenic substitution habitats.  相似文献   
720.
Deforestation is a primary driver of biodiversity change through habitat loss and fragmentation. Stream biodiversity may not respond to deforestation in a simple linear relationship. Rather, threshold responses to extent and timing of deforestation may occur. Identification of critical deforestation thresholds is needed for effective conservation and management. We tested for threshold responses of fish species and functional groups to degree of watershed and riparian zone deforestation and time since impact in 75 streams in the western Brazilian Amazon. We used remote sensing to assess deforestation from 1984 to 2011. Fish assemblages were sampled with seines and dip nets in a standardized manner. Fish species (n = 84) were classified into 20 functional groups based on ecomorphological traits associated with habitat use, feeding, and locomotion. Threshold responses were quantified using threshold indicator taxa analysis. Negative threshold responses to deforestation were common and consistently occurred at very low levels of deforestation (<20%) and soon after impact (<10 years). Sensitive species were functionally unique and associated with complex habitats and structures of allochthonous origin found in forested watersheds. Positive threshold responses of species were less common and generally occurred at >70% deforestation and >10 years after impact. Findings were similar at the community level for both taxonomic and functional analyses. Because most negative threshold responses occurred at low levels of deforestation and soon after impact, even minimal change is expected to negatively affect biodiversity. Delayed positive threshold responses to extreme deforestation by a few species do not offset the loss of sensitive taxa and likely contribute to biotic homogenization.  相似文献   
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