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This paper discusses current research for development of model-based generic algorithms for design and control of reconfigurable interdependent systems. This work is based on extension of Graph Trace Analysis (GTA), which was originally developed in the 1990s for power distribution system design. Because of GTA's ability to combine and restructure analysis methodologies from a variety of problem domains, it is now being used for integrated power distribution and transmission system design, operations, and control. Over the last few years research has begun to formalize GTA into a multidiscipline approach that uses generic algorithms and a common model-based analysis framework. The paper provides an overview of the concepts used in GTA, and then discusses how GTA and generic algorithms can be used together for design and control of multidiscipline systems. This new approach includes decoupling component and system level equations, using iterators to structure iterative analysis that simplifies coordination of discrete events and also eliminates the need for large matrices, using composition to implement polymorphism and simplify data management, using dependency components to structure analysis across different systems types, and implementation of hot-swappable algorithms.  相似文献   
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Historically, human systems integration (HSI) and other operational issues are not addressed during the science and technology (S&T) phase because the focus is on technology development. That view is to solve the "tough science" first, and the rest is simple application by a program office or operational forces. An imbalance between technology development efforts and total system performance considerations, e.g., total ownership cost, workload, manning, training, operational concept, skills, and human performance, leads to suboptimal solutions at best, and at worst prevents the technology's benefits from transitioning out of S&T at all. If HSI is not addressed during the S&T phase, the responsibility falls to the acquisition programs to ensure that operator, maintainer, and total system performance are optimized in the final design. By this point, cost and schedule constraints can make this prohibitive, limiting the options to either using a legacy system or accepting the technology with suboptimal performance and high life-cycle costs (because design problems lead to manpower, training, and human error problems). However, if the S&T community uses HSI in their technology readiness level evaluation criteria, the Department of Defense can reduce its out-year costs and recapitalize that funding to buy required weapons systems and platforms while still reaping the tactical benefits that a new technology offers.  相似文献   
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Between 1980 and 1989 container TEUs handled at all world ports increased by a factor of 2.11. On the East Coast of North America, the growth factor was only 1.69; on the West Coast, 2.23. These growth factors, when multiplied by the 1980 TEU volume at individual North American ports, give 1989 expected performance levels for the ports. Comparing the expected performance to the actual, it is found in the Canadian context that the big winner is Vancouver; the big loser is Saint John. Halifax and Montreal have outperformed their nearest US East Coast rivals but have not performed as well as southern ports on the Altantic Seaboard. These and other comparisons are made in order to describe how Canadian container ports have performed in the decade of the 1980s. The paper then speculates on how the ports will do in the future, based on a discussion of five factors: port facilities; inland transportation connections; shipping lines serving the ports; demand for container shipping; and legal arrangements between the United States and Canada.  相似文献   
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This article analyzes institutional arrangements for the delivery of coastal programs through a new way of thinking about their evolution and structure. The notion of three distinct "dimensions" describing the phases in the evolution of institutional arrangements is introduced. The notion of dimensions is developed from conceptualizing about how institutional arrangements are diagrammed. This allows the visualization of how individual institutions and key stakeholders relate to each other in the delivery of coastal programs, how effective these relationships are, and how their relationships could be redesigned. "Dimensional thinking" enables the re-examination of existing institutional design of coastal programs and how these can evolve to meet the challenges of the new millennium. It is concluded that institutional arrangements have grown from a single dimensional view, where institutions (mainly governmental) delivered programs in isolation, through to the present second dimension where agency programs are managed through coordinating bodies and through coastal management plans. It is argued that a third dimension of institutional arrangements, one that recognizes and embraces the rapid pace of change in this century, will be needed that is aligned by themes rather than by organizational structure. To illustrate a third dimension a visualization tool is developed drawing from management cybernetics. It recognizes the increasing importance of formal and informal networks in relation to traditional modernist hierarchical management by recognizing multiple stakeholders (government at all levels, industry, advocacy groups, conservation interests, and the broader community) and their degree of mutual dependence. Dimensional thinking has the potential to institutionalize the interaction between these multiple stakeholders to ensure the effective delivery of coastal programs in the new millennium. A single answer to what the third dimension of coastal management program evolution should include is not presented. Rather, an approach is presented that allows coastal managers to move forward in the debate on redesigning coastal programs to meet today's complex suite of issues, values, and interests. An experimental case study from Western Australia is used to illustrate the potential application of the dimensional thinking to coastal management institutional design in that State's coastal program.  相似文献   
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Northrop Grumman Corporation has been developing 10 kV SiC MOSFETs and Junction Barrier Schottky diodes for application to a 13.8 kV 2.7 MVA solid-state power substation. The design of half-bridge power modules has extensively used simulation, from electron-level device simulations to the system-level trade studies, to develop the most efficient module for use in the SSPS.  相似文献   
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In order to meet its obligations for prompt and sustained combat at sea, the US Navy relies on sailors to perform relentlessly while underway in highly stressful combat environments. The Navy currently uses an afloat staffing policy that is calculated using a 70-hour workweek per sailor metric. However, this construct fails to factor in an individual sailor's capacity to sustain performance and is based instead on a notional Navy standard workweek. Part of the inadequacy of the current staffing policy results from its failure to consider an inviolable and basic physiological requirement for adequate sleep and rest for sailors. Research indicates a strong causal relationship between sleep and performance. When deprived of sleep, either chronically or acutely, human performance suffers in a dramatic and predictable manner. These performance decrements have even been equated to the effects of alcohol. If the US Navy is to deliver the combat capability demanded by our government and stated in Navy governing documents, sleep and rest requirements must be accounted for in staffing methodologies. To achieve full combat capability, the Navy must change its culture and adopt programs that promote crew endurance. Human system integration can provide a means to accomplish this goal.  相似文献   
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Field studies have demonstrated that it is possible to evaluate the state of many shipboard systems by analyzing the electrical power that is drawn by electromechanical actuators. This paper demonstrates how a device known as a non-intrusive load monitor (NILM) uses only electrical power data to detect several critical faults in shipboard fluid systems. Using the example of reverse-osmosis units installed aboard the US Coast Guard's Medium Endurance Cutters, it is shown that the NILM can provide ship's force with a highly reliable real-time system monitoring capability.  相似文献   
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The United States Government Accountability Office (GAO) has identified problems with the way in which the Department of Defense addresses the growing threat of chemical, biological, radiological, and nuclear (CBRN) weapons. This article describes the conclusions and recommendations of the GAO report. It further analyzes the CBRN threat, the past response of the US Navy to the threat, and how that threat may affect future naval operations. The impact of the potential threat on warship design and performance is discussed. An ad hoc set of design guidelines that can minimize the impact of future threat developments on warship performance is presented.  相似文献   
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