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71.
Horizontal subsurface flow constructed wetlands have proven their efficiency in treating wastewater and removing the pollutants of concern. Treatment efficiency depends on the wastewater residence time, which is a function of the hydraulic loading and the physical conditions of the constructed filter system, which can be described with effective parameters such as: hydraulic conductivity, porosity, dispersivity etc. Because spatial variability is often scale dependent, these effective parameters may be affected by the scale of the system being studied. In this paper the results of tracer experiments in constructed filters using saturated horizontal flow at three scales (small and medium lab scales and full-scale system) using the same filter media is reported. Light-weight aggregate (filter media termed Filtralite-P) was used at all scales. Increasing the scale was associated with increasing dispersivity, meanwhile hydraulic conductivity experienced dramatic reduction and variation by increasing the examined scale. Observed changes in the hydraulic parameters indicate that heterogeneity at different scales should be taken into account when the performance of LWA filters are evaluated from small-scale experiments. 相似文献
72.
There has been growing interest within the economics discipline in the role of equity concerns in the distribution of resources. This paper presents empirical evidence from controlled laboratory experiments where third-party decision makers allocate resources between two individuals. The experimental results indicate that subjects view a wide range of different allocations as the fair distribution of resources. However, regression analysis indicates that both treatment effects and a few demographic variables explain some of this variation in fairness concepts. Most significantly, decision makers rewarded subjects who earned their favorable positions, and the gender of the decision maker was an important predictor of the allocation chosen. 相似文献
73.
E. L. Zhitkova 《Studies on Russian Economic Development》2008,19(1):70-79
The paper focuses on the emerging system of territorial strategic planning in the constituent entities of the Russian Federation and municipalities. Suggested for practical application are the best Russian research studies and practices of coordinating the interests of municipal and regional authorities. The analysis of scholarly approaches to the issue in focus allows one to infer that the best elaborated position is that of the staff of the North-Western Office of the Russian Research Center for Local Governance (RRCLG). As regards the express-analysis of practices adopted in the number of the Russian Federation constituent entities, the practices of the Krasnodar krai appear to be the most promising. 相似文献
74.
Faced with a record level of unemployment, the present debate in Germany is to extend the weekly hours of work. In this paper the employment effects of an economy-wide increase in weekly hours are quantified on the basis of a computable general equilibrium model for different specifications of the wage setting rule and the use of additional policy-induced public income. The simulation results back the argument of the opponents of longer working time that not more jobs will be created. However, when the higher tax revenues from GDP growth are used to reduce social security contributions, then the claim of the proponents that more jobs will be created can be supported. 相似文献
75.
Leonard L. Berry 《Journal of the Academy of Marketing Science》1995,23(4):236-245
Relationship marketing is an old idea but a new focus now at the forefront of services marketing practice and academic research.
The impetus for its development has come from the maturing of services marketing with the emphasis on quality, increased recognition
of potential benefits for the firm and the customer, and technological advances. Accelerating interest and active research
are extending the concept to incorporate newer, more sophisticated viewpoints. Emerging perspectives explored here include
targeting profitable customers, using the strongest possible strategies for customer bonding, marketing to employees and other
stakeholders, and building trust as a marketing tool. Although relationship marketing is developing, more research is needed
before it reaches maturity. A baker’s dozen of researchable questions suggests some future directions.
holds the J. C. Penney Chair of Retailing Studies, is a professor of Marketing, and is director of the Center for Retailing
Studies at Texas A&M University. He is a former national president of the American Marketing Association. His research interests
are services marketing, service quality, and retailing strategy. He has published numerous journal articles and books, includingDelivering Quality Service: Balancing Customer Perceptions and Expectations (Free Press, 1990),Marketing Services: Competing Through Quality (Free Press, 1991), andOn Great Service: A Framework for Action (Free Press, 1995). 相似文献
76.
Unlike the traditional futures contract risk‐based approach to margining, new security futures contracts are margined under a strategy‐based margining system similar to that which applies in the equity options markets. As a result, these new margin requirements are potentially much less sensitive to changes in market conditions. This article performs a simulation to evaluate whether these alternative margining methodologies can be expected to produce comparable outcomes. The analysis suggests that a 1‐day settlement period will likely lead to collection of customer margins that are virtually always greater than that which its traditional risk‐based counterpart would require. A 4‐day settlement period would lead to margin requirements that both significantly under‐ and overmargin relative to a comparable risk‐based system. This study argues that exchanges may approach the preferred probability of customer exhaustion by managing margin settlement intervals. Thus, the new strategy‐based rules, in and of themselves, will not necessarily inhibit new security futures trading activity. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:989–1002, 2003 相似文献
77.
The primary purpose of this research was to investigate the effect of investment in information technology in a supply chain. The results of that investigation are presented by focusing on an empirically tested supply chain relationship model containing both behavioral and operational constructs. The four behavioral constructs represented in the model are relationship trust, relationship commitment, relationship dependence, and long‐term relationship orientation. The four operational constructs represented in the model are retailer investment in interorganizational information technology, perceived supplier investment in interorganizational information technology, logistics efficiency, and logistics effectiveness. Among other findings, the results of the investigation found that perceived supplier investment in interorganizational information technology has a significant and positive effect on logistics efficiency. 相似文献
78.
Terry L. Esper Thomas D. Jensen Fernanda L. Turnipseed Scot Burton 《Journal of Business Logistics》2003,24(2):177-203
The Internet has increased the level of importance of the end‐consumer market to transportation carriers. In two between subject experiments, carrier disclosure on retail merchant websites is examined as a strategic differentiation strategy. Predictions are offered concerning effects of carrier disclosure strategies on product delivery‐related expectations, consumer attitudes, and intentions to purchase a product online. Results from Study 1 reveal significant differences between disclosure and nondisclosure of the carrier for numerous product delivery‐related variables, as well as many differences between the six carriers examined in this first study. Study 2 extends these findings by showing that providing consumers with a choice of carrier leads to increased levels of satisfaction with the online experience and greater willingness to buy, relative to nondisclosure and disclosure strategies. 相似文献
79.
Close relationships between and among supply chain members are becoming more prevalent. However, there is lack of agreement in the literature and in practice concerning the characteristics of different interorganizational relationships. The resultant confusion is an obstacle to the progression of research and could cause problems among firms in a supply chain. Based on previous research and an exploratory study conducted with company executives responsible for supply chain management activities, this article seeks to introduce the concept of relationship magnitude (i.e., the extent or degree of closeness or strength of the relationship) and differentiate it from relationship type (i.e., classes of relationships that share common traits). Implications for managers and opportunities for future research are provided. 相似文献
80.
The electrolytical methanogenic/methanotrophic coupling (eMaMoC) process was tested in a laboratory-scale single-stage reactor for the treatment of tetrachloroethene (PCE)-contaminated waters. A water electrolysis cell was placed directly in the effluent recirculation loop for the supply of both O2 and H2 to the system: H2 serving as the electron donor for both carbonate reduction into CH4 and reductive dechlorination. The concurrent presence of O2 and CH4 could be used by the methanotrophs for co-metabolically oxidising the chlorinated intermediates left over by the anaerobic transformation of PCE. At a PCE inlet of 33-52 microM and a hydraulic residence time (HRT) of 5.6 days, PCE reductive dechlorination to dichloroethene (DCE) was over 95% with a maximum DCE mineralisation of 83%. Fluorescence in situ hybridisation with 16S rRNA probes related to type I and type II methanotrophic bacteria were utilised to localise the methanotrophic communities in the anaerobic/aerobic granules. It evidenced that with operational time, along with increasing oxygenation rate, methanotrophic communities were specifically colonising onto the outermost layer of the anaerobic/aerobic granule. 相似文献