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141.
Oxidation and mineralisation of substituted phenols by Fenton's reagent and catalytic wet oxidation.
Catalytic abatement of solutions of 1,000 mg/L in phenol, ortho and para nitrophenol and ortho and para cresols was acomplished by using two catalytic systems. Fenton's reagent was used at 50 degrees C by adding 10 mg/L of ferrous cation and different dosages of H2O2. The mixture was reacting isothermically in a batch way during 3 hours. Catalytic wet oxidation (CWO) was carried out by using a commercial Activated Carbon, Industrial React FE01606A, CWO runs were carried out in a fixed bed reactor (FBR) with concurrent upflow. Temperature and oxygen pressure of the reactor were set to 160 degrees C and 16 bar, respectively. While phenols are quicky oxidised by the Fenton reagent higher mineralisation was obtained in the CWO process. 相似文献
142.
The secondary effluent from municipal plants in Korea generally represents higher BOD with lower SS. Therefore, more soluble forms of organics and NH4-N need to be removed to improve its effluent for reuse. In this study reuse possibility of secondary effluent and CSO (combined sewer overflow) using BAF (biological aerated filter) was evaluated. The tertiary application with 1.2 h EBCT, SS, BOD and COD showed stable concentrations less than 1.3, 1.3 and 6.2 mg/L, respectively. Nitrogen could be nitrified even at 7 degrees suggesting BAF can be used for a water reuse method as well as an effective add-on facility in cold regions. However, BAF was not stable with CSO application at increased flow rates suggesting CSO must be equalised prior to application. Disinfection was necessary even during normal weather conditions. 相似文献
143.
We argue that firms with interdependent worker productivity, team production, have a higher cost of absence and, as a consequence, spend additional resources on monitoring absence. As a result, firms with team production should have lower absence rates. We estimate the determinants of absence for blue‐collar workers using a sample of German manufacturing establishments. Workplace teams are used as a proxy for team production. The estimates reveal that firms with teams have lower absence rates, as do smaller establishments. The size effect, however, is unique to establishments with teams, which fits prior theoretical work that has not been previously tested. 相似文献
144.
This paper deals with on-line computation—or step-wise learning—of Pareto optimal insurance contracts. Our approach tolerates that the loss distribution might be unknown, intractable, or not well specified. Thus we accommodate fairly inexperienced parties. Losses are here simulated or observed, one at a time, and they cause iterated revisions of the premium. The mechanical and global nature of probability calculus thereby yields to more tentative, myopic procedures, possibly closer to how humans operate or reason in face of risk. Sequential revisions may also reduce the expense of insurers' time and money in seeking sufficient statistics. Emphasized below is the remarkable simplicity and stability of the resulting adaptive procedures. Special attention goes to catastrophic risks, and to subsidized or competitive insurance. 相似文献
145.
Optimal Operation of Reservoir Systems using Simulated Annealing 总被引:5,自引:0,他引:5
A stochastic search technique, simulated annealing (SA), is used to optimize the operation of multiple reservoirs. Seminal application of annealing technique in general to multi-period, multiple-reservoir systems, along with problem representation and selection of different parameter values used in the annealing algorithm for specific cases is discussed. The search technique is improved with the help of heuristic rules, problem-specific information and concepts from the field of evolutionary algorithms. The technique is tested for application to a benchmark problem of four-reservoir system previously solved using a linear programming formulation and its ability to replicate the global optimum solution is examined. The technique is also applied to a system of four hydropower generating reservoirs in Manitoba, Canada, to derive optimal operating rules. A limited version of this problem is solved using a mixed integer nonlinear programming and results are compared with those obtained using SA. A better objective function value is obtained using simulated annealing than the value from a mixed integer non-linear programming model developed for the same problem. Results obtained from these applications suggest that simulated annealing can be used for obtaining near-optimal solutions for multi-period reservoir operation problems that are computationally intractable. 相似文献
146.
Analysis of the US cruise line industry 总被引:1,自引:0,他引:1
J. S. Perry Hobson 《Tourism Management》1993,14(6)
The cruise line industry has been through a metamorphosis. From being a declining mode of travel in the 1960s, the cruise line industry turned the corner in the 1970s and became one of the fastest growing segments of the wider tourism industry during the 1980s. This paper examines the reasons behind this growth, the current structure of the US cruise industry and the issues facing the industry in the 1990s as it heads towards the next century. 相似文献
147.
148.
There has been an extensive body of research conducted into the technical aspects of the just-in-time (JIT) manufacturing methodology, particularly prior to 1990. It is only in more recent times that the focus has turned toward the more subtle people-related aspects. The recognition of JIT as a truly holistic approach to managing manufacturing operations has led to an appreciation of the importance of the role played by the human variable as well as an emphasis on the impact that organisational structure and management style can have on successful operation. This article examines and analyses the content of a wide range of articles related to issues such as: the need for change in corporate culture, the role of organisational structures, factors significantly impacting chances of success, the importance of employee involvement, how best to involve employees, the importance of training, how/whom/when to train, different team-based organisational structures, the impact of changing roles on various levels of the organisation and the appropriateness of particular change management strategies. An overall picture of the current state of thinking on these issues is thus developed and the importance of these factors to the successful implementation and operation of JIT highlighted. Opportunities for further research in this important area are identified. 相似文献
149.
Paula S. Weber James E. Weber Bradley R Sleeper Ken L. Schneider 《Journal of Business Ethics》2004,49(4):359-369
This paper presents the development andvalidation of new measurement tools to exploreself-efficacy toward service and toward civicparticipation. We developed and administereda survey to 851 students in an AACSB-accreditedcollege of business at a comprehensive publicuniversity located in the Midwest. Traditionalscale development methodologies plusconfirmatory factor analysis and simultaneousfactor analysis in several populations wereused to analyze both a primary sample and aholdback sample. Results strongly support thevalidity and reliability of the surveyinstrument. Future use for the instrumentincludes verification of the effectiveness ofpedagogies designed to increase self-efficacytoward service and motivation for civicparticipation in business students. 相似文献
150.
Heidi S.C.A. MuijenHeidi 《Journal of Business Ethics》2004,53(1-2):235-246
The author addresses the question of how to use value-learning processes to integrate corporate social responsibility (CSR) in organizations as an interesting challenge in (higher) education. Two strategies have been proposed for the issue of CSR: a compliance strategy and a cultural change strategy (Karssing, 2001). This article focuses on the ethical and philosophical presuppositions of these different approaches. The incorporation of CSR in organizations cannot be accomplished by means of a compliance strategy only. Rather, it needs to be supplemented by a strategy aimed at stimulating a transformation process on the corporate culture level. The perspective of change through dialogue is proposed as a means of innovating the curriculum and the primary processes of student education. This organizational change perspective is demonstrated by describing how (ethical) reflective aspects are integrated in the curriculum of the Free University of Amsterdam. An additional case study on organizational value learning is presented to illustrate the thesis that CSR presupposes that university is an adequate context where life-long learning begins. 相似文献