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1.
J Comas I Rodríguez-Roda M Poch K V Gernaey C Rosen U Jeppsson 《Water science and technology》2006,53(4-5):303-311
Wastewater treatment plant operators encounter complex operational problems related to the activated sludge process and usually respond to these by applying their own intuition and by taking advantage of what they have learnt from past experiences of similar problems. However, previous process experiences are not easy to integrate in numerical control, and new tools must be developed to enable re-use of plant operating experience. The aim of this paper is to investigate the usefulness of a case-based reasoning (CBR) approach to apply learning and re-use of knowledge gained during past incidents to confront actual complex problems through the IWA/COST Benchmark protocol. A case study shows that the proposed CBR system achieves a significant improvement of the benchmark plant performance when facing a high-flow event disturbance. 相似文献
2.
In this paper, implementation of the Benchmark Simulation Model No 2 (BSM2) within Matlab-Simulink is presented. The BSM2 is developed for plant-wide WWTP control strategy evaluation on a long-term basis. It consists of a pre-treatment process, an activated sludge process and sludge treatment processes. Extended evaluation criteria are proposed for plant-wide control strategy assessment. Default open-loop and closed-loop strategies are also proposed to be used as references with which to compare other control strategies. Simulations indicate that the BM2 is an appropriate tool for plant-wide control strategy evaluation. 相似文献
3.
Intensive use of the benchmark simulation model No. 1 (BSM1), a protocol for objective comparison of the effectiveness of control strategies in biological nitrogen removal activated sludge plants, has also revealed a number of limitations. Preliminary definitions of the long-term benchmark simulation model No. 1 (BSM1_LT) and the benchmark simulation model No. 2 (BSM2) have been made to extend BSM1 for evaluation of process monitoring methods and plant-wide control strategies, respectively. Influent-related disturbances for BSM1_LT/BSM2 are to be generated with a model, and this paper provides a general overview of the modelling methods used. Typical influent dynamic phenomena generated with the BSM1_LT/BSM2 influent disturbance model, including diurnal, weekend, seasonal and holiday effects, as well as rainfall, are illustrated with simulation results. As a result of the work described in this paper, a proposed influent model/file has been released to the benchmark developers for evaluation purposes. Pending this evaluation, a final BSM1_LT/BSM2 influent disturbance model definition is foreseen. Preliminary simulations with dynamic influent data generated by the influent disturbance model indicate that default BSM1 activated sludge plant control strategies will need extensions for BSM1_LT/BSM2 to efficiently handle 1 year of influent dynamics. 相似文献
4.
The paper argues that although considerations such as industry consolidation, the role of lending and the effects of technology are still important in shaping the future of investment banking, sustainable competitive advantage necessitates that emphasis is also placed on thought leadership. This entails quite a radical change in terms of the way in which the industry approaches the problem of competition and requires emphasis on value creation for all the constituent parts of the industry: corporations, investors, the banks themselves and research departments. Accordingly, the paper provides a rationale for this change and provides inter alia a range of examples to illustrate how thought leadership could lead to a fundamental change in the future of the investment banking industry. 相似文献
5.
We argue that charismatic leadership can influence external support for the organization, particularly in making the company more attractive to outside investors. Two studies were conducted to test this general hypothesis. First, an archival study demonstrated that the stock of companies headed by charismatic leaders appreciated more than the stock of comparable companies, even after differences in corporate performance were controlled. It was also found that the effect of charismatic leadership was heightened under more difficult economic conditions. Second, an experiment was conducted in which the salience of charismatic leadership was manipulated, along with information about the prospects for an organization's turnaround. Results showed that appeals from a charismatic leader led to increased investment in the firm, and the leader's influence was greater when the prospects for an organizational turnaround were more difficult. It was also found that an endowment of stock enhanced the influence of charismatic appeals and that charismatic leadership may have affected the general risk propensities of followers. These findings were interpreted in terms of an external perspective on leadership, illustrating how leaders can manage the firm's economic and social environment. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
6.
This paper sets out to analyse the effect of plant and sectoral level characteristics on the provision of training to employees using plant level data for Irish manufacturing. There is no clear evidence that foreign owned plants are more likely to provide training. By contrast, we find that they spend less than domestic plants on training, ceteris paribus. There is also no evidence that plants that receive training grants are more likely to provide training. This may be likely to reflect the targeting of training grants on plants that are otherwise unlikely to provide much training. We do, however, find that training activity in the sector, either by other foreign or domestic plants, has a positive effect on plant level training activity, at least for domestic owned plants. 相似文献
7.
Poverty Traps and Index-Based Risk Transfer Products 总被引:1,自引:0,他引:1
8.
O Bernard B Chachuat A Hélias B Le Dantec B Sialve J-P Steyer L Lardon P Neveu S Lambert J Gallop M Dixon P Ratini A Quintabà S Frattesi J M Lema E Roca G Ruiz J Rodriguez A Franco P Vanrolleghem U Zaher D J W De Pauw K De Neve K Lievens D Dochaine O Schoefs H Fibrianto R Farina V Alcaraz Gonzalez V Gonzalez Alvarez P Lemaire J A Martinez F Esandi O Duclaud J F Lavigne 《Water science and technology》2005,52(1-2):457-464
The TELEMAC project brings new methodologies from the Information and Science Technologies field to the world of water treatment. TELEMAC offers an advanced remote management system which adapts to most of the anaerobic wastewater treatment plants that do not benefit from a local expert in wastewater treatment. The TELEMAC system takes advantage of new sensors to better monitor the process dynamics and to run automatic controllers that stabilise the treatment plant, meet the depollution requirements and provide a biogas quality suitable for cogeneration. If the automatic system detects a failure which cannot be solved automatically or locally by a technician, then an expert from the TELEMAC Control Centre is contacted via the internet and manages the problem. 相似文献
9.
A bstract Previous theoretical and empirical research on economic sociology leaves much to be desired in terms of consistently defining the agenda and objectives of the discipline As a result, economic sociology often appears to lack a clearly defined mission and purpose This is epitomized by various failures to establish adequate epistemological relations of the proper realm of economic sociology with those of economics and sociology, and especially with the domain of rational choice theory This failure is compounded by a misplaced distinction between the subject matter of economic sociology and that of sociological economics, or socioeconomics And some recent works in the discipline (including the ambitious Handbook of Economic Sociology ) have not helped to remedy this situation In this paper, we try to address this situation by suggesting some reformulations of the subject matter of economic sociology in relation to those of related disciplines In addition, we attempt to redefine the field of the sociology of the market which is seen as the focal specialty of economic sociology 相似文献
10.
Quantitative analyses of flow and stage data, remote sensing and geographic information systems analysis, and field studies were used to assess the impact of dams and diversions on the point bar habitat of the Sacramento Valley Tiger Beetle (Cicindela hirticollis abrupta). The reaches of interest include sites of known historic populations of C. h. abrupta along the Sacramento River from approximately 8 km north of Colusa southward to the confluence with the Feather River and along the Feather River between Yuba City and its confluence with the Sacramento River. The results from this study show that construction of two major dams has altered flows such that prolonged and increased flows during summer, fall, and early winter have most likely disrupted life cycles, flooded larvae, drowned overwintering adults and led to high mortality. Additionally, habitat availability has decreased over time because point bars have decreased in number and area causing increased distances between populations and isolation of populations. Moreover, point bar armouring, channel scouring, altered flows, redirected flows through weirs, and lithologic controls have produced a bimodal distribution of mean grain sizes in the Sacramento River in which the more northern bars contain gravel deposits and more southern bars possess fine sands. These conditions negatively alter moisture retention and sediment compaction and, consequently, burrowing conditions needed by this tiger beetle. Additionally, more stabilized flows (reduced variability) and increased fine‐grained deposition have enabled development and encroachment of vegetation onto the sand bars. Finally, human stresses, such as foot traffic and vehicular traffic may have interfered with burrowing, ovipositing, and foraging. The combination of these stress factors has most likely led to a reduction in source populations and, ultimately, the apparent extirpation of the entire metapopulation. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献