985 resultados para Navigation equipment industry
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This paper presents a methodology for the study of a molten carbonate fuel cell co-generation system. This system is applied to a dairy industry of medium size that typically demands 2100 kW of electricity, 8500 kg/h of saturated steam (P = 1.08 MPa) and 2725 kW of cold water production. Depending on the associated recuperation equipment, the co-generation system permits the recovery of waste heat, which can be used for the production of steam, hot and cold water, hot and cold air. In this study, a comparison is made between two configurations of fuel cell co-generation systems (FCCS). The plant performance has been evaluated on the basis of fuel utilisation efficiency and each system component evaluated on the basis of second law efficiency. The energy analysis presented shows a fuel utilisation efficiency of about 87% and exergy analysis shows that the irreversibilities in the combustion chamber of the plant are significant. Further, the payback period estimated for the fuel cell investment between US$ 1000 and US$ 1500/k-W is about 3 and 6 years, respectively. (C) 2002 Elsevier B.V. B.V. All rights reserved.
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Includes bibliography
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Includes bibliography
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The greatest challenge of undergraduate engineering courses is to encourage creativity, cooperation with other students, teamwork, and motivation in the first years of their courses. While students have little or no contact with advanced disciplines, it is very difficult to attract their interests and encourage them to develop the skills in their undergraduate courses. This work aims to achieve these objectives through a mini-factory project involving the construction of a production line of ceramic tiles on a laboratory scale, from the ceramic processing using raw materials to the shipping of the final product. Having been given an established monthly demand for ceramic tiles, the students determined the construction requirements of the mini-factory, as they have created the layout, including the processing equipment, the dimensioning of equipment, and its operational structure. This article intends to describe the successful creation of the ceramic tile mini-factory, including the objectives, benefits, and inherent difficulties of the process and the receptivity of the exercise by the students involved.
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In recent approaches to the management of product development process (PDP), maturity levels have attracted the attention of practitioners and researchers. The CMMI model contributes to evaluate the maturity levels and improvement of the product development process management. This paper, based on CMMI model, analyzes the practices adopted in two companies of the capital goods industry, which develop and manufacture equipment upon request. It was observed that on account of market conditioning factors and different practices adapted to PDP management, these companies are at different maturity levels. One company is at the initial level of maturity while the other at the most advanced one. It was also noted that the application of CMMI model can provide improvement to PDP management, as well as present guidelines to achieve higher maturity levels, adequate to companies' needs.
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In the first paper presented to you today by Dr. Spencer, an expert in the Animal Biology field and an official authority at the same time, you heard about the requirements imposed on a chemical in order to pass the different official hurdles before it ever will be accepted as a proven tool in wildlife management. Many characteristics have to be known and highly sophisticated tests have to be run. In many instances the governmental agency maintains its own screening, testing or analytical programs according to standard procedures. It would be impossible, however, for economic and time reasons to work out all the data necessary for themselves. They, therefore, depend largely on the information furnished by the individual industry which naturally has to be established as conscientiously as possible. This, among other things, Dr. Spencer has made very clear; and this is also what makes quite a few headaches for the individual industry, but I am certainly not speaking only for myself in saying that Industry fully realizes this important role in developing materials for vertebrate control and the responsibilities lying in this. This type of work - better to say cooperative work with the official institutions - is, however, only one part and for the most of it, the smallest part of work which Industry pays to the development of compounds for pest control. It actually refers only to those very few compounds which are known to be effective. But how to get to know about their properties in the first place? How does Industry make the selection from the many thousands of compounds synthesized each year? This, by far, creates the biggest problems, at least from the scientific and technical standpoint. Let us rest here for a short while and think about the possible ways of screening and selecting effective compounds. Basically there are two different ways. One is the empirical way of screening as big a number of compounds as possible under the supposition that with the number of incidences the chances for a "hit" increase, too. You can also call this type of approach the statistical or the analytical one, the mass screening of new, mostly unknown candidate materials. This type of testing can only be performed by a producer of many new materials,that means by big industries. It requires a tremendous investment in personnel, time and equipment and is based on highly simplified but indicative test methods, the results of which would have to be reliable and representative for practical purposes. The other extreme is the intellectual way of theorizing effective chemical configurations. Defenders of this method claim to now or later be able to predict biological effectiveness on the basis of the chemical structure or certain groups in it. Certain pre-experience should be necessary, that means knowledge of the importance of certain molecular requirements, then the detection of new and effective complete molecules is a matter of coordination to be performed by smart people or computers. You can also call this method the synthetical or coordinative method.
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The increasing aversion to technological risks of the society requires the development of inherently safer and environmentally friendlier processes, besides assuring the economic competitiveness of the industrial activities. The different forms of impact (e.g. environmental, economic and societal) are frequently characterized by conflicting reduction strategies and must be holistically taken into account in order to identify the optimal solutions in process design. Though the literature reports an extensive discussion of strategies and specific principles, quantitative assessment tools are required to identify the marginal improvements in alternative design options, to allow the trade-off among contradictory aspects and to prevent the “risk shift”. In the present work a set of integrated quantitative tools for design assessment (i.e. design support system) was developed. The tools were specifically dedicated to the implementation of sustainability and inherent safety in process and plant design activities, with respect to chemical and industrial processes in which substances dangerous for humans and environment are used or stored. The tools were mainly devoted to the application in the stages of “conceptual” and “basic design”, when the project is still open to changes (due to the large number of degrees of freedom) which may comprise of strategies to improve sustainability and inherent safety. The set of developed tools includes different phases of the design activities, all through the lifecycle of a project (inventories, process flow diagrams, preliminary plant lay-out plans). The development of such tools gives a substantial contribution to fill the present gap in the availability of sound supports for implementing safety and sustainability in early phases of process design. The proposed decision support system was based on the development of a set of leading key performance indicators (KPIs), which ensure the assessment of economic, societal and environmental impacts of a process (i.e. sustainability profile). The KPIs were based on impact models (also complex), but are easy and swift in the practical application. Their full evaluation is possible also starting from the limited data available during early process design. Innovative reference criteria were developed to compare and aggregate the KPIs on the basis of the actual sitespecific impact burden and the sustainability policy. Particular attention was devoted to the development of reliable criteria and tools for the assessment of inherent safety in different stages of the project lifecycle. The assessment follows an innovative approach in the analysis of inherent safety, based on both the calculation of the expected consequences of potential accidents and the evaluation of the hazards related to equipment. The methodology overrides several problems present in the previous methods proposed for quantitative inherent safety assessment (use of arbitrary indexes, subjective judgement, build-in assumptions, etc.). A specific procedure was defined for the assessment of the hazards related to the formations of undesired substances in chemical systems undergoing “out of control” conditions. In the assessment of layout plans, “ad hoc” tools were developed to account for the hazard of domino escalations and the safety economics. The effectiveness and value of the tools were demonstrated by the application to a large number of case studies concerning different kinds of design activities (choice of materials, design of the process, of the plant, of the layout) and different types of processes/plants (chemical industry, storage facilities, waste disposal). An experimental survey (analysis of the thermal stability of isomers of nitrobenzaldehyde) provided the input data necessary to demonstrate the method for inherent safety assessment of materials.
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The purpose of this study is to provide a procedure to include emissions to the atmosphere resulting from the combustion of diesel fuel during dredging operations into the decision-making process of dredging equipment selection. The proposed procedure is demonstrated for typical dredging methods and data from the Illinois Waterway as performed by the U.S. Army Corps of Engineers, Rock Island District. The equipment included in this study is a 16-inch cutterhead pipeline dredge and a mechanical bucket dredge used during the 2005 dredging season on the Illinois Waterway. Considerable effort has been put forth to identify and reduce environmental impacts from dredging operations. Though environmental impacts of dredging have been studied no efforts have been applied to the evaluation of air emissions from comparable types of dredging equipment, as in this study. By identifying the type of dredging equipment with the lowest air emissions, when cost, site conditions, and equipment availability are comparable, adverse environmental impacts can be minimized without compromising the dredging project. A total of 48 scenarios were developed by varying the dredged material quantity, transport distance, and production rates. This produced an “envelope” of results applicable to a broad range of site conditions. Total diesel fuel consumed was calculated using standard cost estimating practices as defined in the U.S. Army Corps of Engineers Construction Equipment Ownership and Operating Expense Schedule (USACE, 2005). The diesel fuel usage was estimated for all equipment used to mobilize and/or operate each dredging crew for every scenario. A Limited Life Cycle Assessment (LCA) was used to estimate the air emissions from two comparable dredging operations utilizing SimaPro LCA software. An Environmental Impact Single Score (EISS) was the SimaPro output selected for comparison with the cost per CY of dredging, potential production rates, and transport distances to identify possible decision points. The total dredging time was estimated for each dredging crew and scenario. An average hourly cost for both dredging crews was calculated based on Rock Island District 2005 dredging season records (Graham 2007/08). The results from this study confirm commonly used rules of thumb in the dredging industry by indicating that mechanical bucket dredges are better suited for long transport distances and have lower air emissions and cost per CY for smaller quantities of dredged material. In addition, the results show that a cutterhead pipeline dredge would be preferable for moderate and large volumes of dredged material when no additional booster pumps are required. Finally, the results indicate that production rates can be a significant factor when evaluating the air emissions from comparable dredging equipment.
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Offset printing is a common method to produce large amounts of printed matter. We consider a real-world offset printing process that is used to imprint customer-specific designs on napkin pouches. The production equipment used gives rise to various technological constraints. The planning problem consists of allocating designs to printing-plate slots such that the given customer demand for each design is fulfilled, all technological and organizational constraints are met and the total overproduction and setup costs are minimized. We formulate this planning problem as a mixed-binary linear program, and we develop a multi-pass matching-based savings heuristic. We report computational results for a set of problem instances devised from real-world data.
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This paper examines the process and mechanism of economic development in the Republic of Korea and Taiwan through a comparative analysis of the electronics industry in each country. The paper will show that in its initial stage of development, the electronics industry in both economies had the same type of dual structure: a domestic demand sector based on the protected domestic market, and an export sector intended to capitalize on low-wage labor for the international market. However, this dual structure in the two economies faded away after the mid-1970s as their respective indigenous export-oriented enterprises began to develop. But the primary industrial players in each economy were very different. In Korea they were comprehensive electronics manufacturers affiliated with chaebols, and in Taiwan they were small and medium-size enterprises. Differences in the two economies' development mechanisms have brought about this divergence in development paths. In Korea this mechanism has been characterized by the government's positive role and the chaebol's readiness to react to the government's leadership. In Taiwan the development mechanism has been based on the private sector independent from the government. As an extension of such diverged development paths, ICs and personal computers showed spectacular growth in Korea and Taiwan after the 1980s. The development of ICs in Korea was primarily the result of a decisive role played by the chaebol's sizable financial resources, while the competitiveness in personal computers largely reflected the agility and flexibility of Taiwanese small and medium-size enterprises.
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This paper examines the impact of China's recent rise on the development of local firms in latecomer developing countries. Based on a detailed analysis of Vietnam's motorcycle industry, the paper argues that China's impact may go beyond what a trade analysis suggests. Indeed, China's rise induced a dynamic transformation in the structure of value chains within Vietnam's motorcycle industry, bringing about far-reaching consequences on the development and upgrading trajectories of local firms. The implications of the case study for the wider "global value chain" approach is also discussed.
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Economic backwardness often influences the growth of firms in developing countries. In this paper, we investigate the growth conditions and paths available for latecomers competing with first movers. Employing the concepts of boundaries of the firm and the disadvantage of backwardness, we present a case study of China's mobile handset industry and proceed to develop a simple model. We find that although significant disadvantage does not allow latecomers to grow, there are possibilities for changing the conditions of growth if latecomers can utilize outside resources and/or indigenous advantages.
Exploiting the Modularity of Value Chains: Inter-firm Dynamics of the Taiwanese Notebook PC Industry
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This paper explores the inter-firm dynamics that govern the rise of capabilities of latecomer firms operating in global value chains. By extending and modifying the model proposed by Gereffi, Humphrey and Sturgeon [2005], I present a framework in which the rise of supplier capabilities is determined by interactions among the strategies of the firms. Based on a case study of the Taiwanese notebook PC industry, the paper will explore how the interactions among outsourcing strategies by lead firms from the developed countries, the learning strategies of Taiwanese suppliers, and the product strategy of powerful component vendors have driven the explosive growth of the industry after the 1990s. By so doing, the paper attempts to highlight the active roles firms play in determining the speed and direction of the rise in supplier capabilities.