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241.
A major component of the US Army's Future Combat Systems (FCS) will be a fleet of eight different manned ground vehicles (MGV). There are promises that "advanced automation" will accomplish many of the tasks formerly performed by soldiers in legacy vehicle systems. However, the current approach to automation design does not relieve the soldier operator of tasks; rather, it changes the role of the soldiers and the work they must do, often in ways unintended and unanticipated. This paper proposes a coherent, top-down, overarching approach to the design of a human–automation interaction model. First, a qualitative model is proposed to drive the functional architecture and human–automation interface scheme for the MGV fleet. Second, the proposed model is applied to a portion of the functional flow of the common crew station on the MGV fleet. Finally, the proposed model is demonstrated quantitatively via a computational task-network modeling program (Improved Performance Research and Integration Tool). The modeling approach offers insights into the impacts on human task-loading, workload, and human performance. Implications for human systems integration domains are discussed, including Manpower and Personnel, Human Factors Engineering, Training, System Safety, and Soldier Survivability. The proposed model gives engineers and scientists a top-down approach to explicitly define and design the interactions between proposed automation schemes and the human crew. Although this paper focuses on the Army's FCS MGV fleet, the model and analytical processes proposed, or similar approaches, are appropriate for many manned systems in multiple domains (aviation, space, maritime, ground transportation, manufacturing, etc.).  相似文献   
242.
Over the past generation seaports have undergone a transformation from traditional cargo handling to logistical support centers and changed from bulk shipping and processing to high value-added management centers in an increasingly competitive global environment. Many have reorganized to become leaders of their region's economic development strategies. This paper reviews these changing roles and their impact on organizational issues. This organizational assessment is applied to the port of Kaohsiung and its envisioned role as a commercial hub and operations centre on the Pacific Rim. Issues such as split lines of responsibility, authority and jurisdiction across different levels of government are considered. Competing goals such as economic development, urban waterfront development, metropolitan urban structure, logistical integration, and infrastructure investment are discussed in this context.  相似文献   
243.
Sampling of the near-bottom calanoid copepods was performed on board of the research vessel Polarstern in 1993 in the Laptev Sea (Siberian Arctic). Three new species of Xanthocalanus were identified as such, and are described and figured here: X. spinodenticulatus sp. nov., X. laptevorum sp. nov. and X. polarsternae sp. nov.  相似文献   
244.
The purpose of this paper is to determine optimal shipping strategies (i.e. routes and shipment sizes) on freight networks by analyzing trade-offs between transportation, inventory, and production set-up costs. Networks involving direct shipping, shipping via a consolidation terminal, and a combination of terminal and direct shipping are considered. This paper makes three main contributions. First, an understanding is provided of the interface between transportation and production set-up costs, and of how these costs both affect inventory. Second, conditions are identified that indicate when networks involving direct shipments between many origins and destinations can be analyzed on a link-by-link basis. Finally, a simple optimization method is developed that simultaneously determines optimal routes and shipment sizes for networks with a consolidation terminal and concave cost functions. This method decomposes the network into separate sub-networks, and determines the optimum analytically without the need for mathematical programming techniques.  相似文献   
245.
DIETARYMAGNESIUMDEFICIENCYINCREASESLEVELSANDFUNCTIONOFGiαINTHERATHEARTAFTERMYOCARDIALINFARCTIONShiBing;J.E.Heavner,L.M.Boylan...  相似文献   
246.
The CAMCAT oil spill forecasting system is presented in this paper, and an evaluation of the impact of errors in the forcing fields over its forecasts is carried out. The system is formed by several independent modules which provide forecasts of winds, currents and waves to an oil spill module which predicts the evolution of the spill.The typical twin-experiments experience is used paying special attention to a realistic characterization of the errors when perturbing the forcing fields. The results suggest that errors in the wind and current fields are the main limiting factor for the quality of the oil spill forecasts. The pollutant identification is also crucial to determine the final vertical position and characteristics of the product.  相似文献   
247.
The Belgian government intends to shift part of its funding away from Antwerp and towards other seaports, particularly Ghent and Zeebrugge. In the long run, this policy change will undoubtedly influence the port choice and probably cause a traffic diversion at the expense of Antwerp. This will have a great influence on the structure of inland transportation.

The impact of port choice on inland transportation is the central theme of this paper. To this end a disaggregated model of the demand for freight transport is constructed.  相似文献   
248.
简单介绍了数据库的运行模式以及如何才能使数据库运行在归档方式.  相似文献   
249.
Public Port Authorities engage in a multimedia of activities under the guise of economic development that may be only marginally linked to the disposition of frieght or passengers. The mix of economic functions is determined as a result of shifts in marine cargo throughput, competition for shorefront land with other non-water-dependent users, the level of power and control wielded by Port personnel, and the legal mandate granted to the Port Authority. These non-marine functions often play an important role both for the Port itself and for the port community, regardless of the size of the port.  相似文献   
250.
The persistence of environmental problems in urban areas and the prospect of increasing congestion have precipitated a variety of new policies in the USA, with concomitant analytical and modeling requirements for transportation planning. This paper introduces the Sequenced Activity-Mobility Simulator (SAMS), a dynamic and integrated microsimulation forecasting system for transportation, land use and air quality, designed to overcome the deficiencies of conventional four-step travel demand forecasting systems. The proposed SAMS framework represents a departure from many of the conventional paradigms in travel demand forecasting. In particular, it aims at replicating the adaptative dynamics underlying transportation phenomena; explicitly incorporates the time-of-day dimension; represents human behavior based on the satisficing, as opposed to optimizing, principle; and endogenously forecasts socio-demographic, land use, vehicle fleet mix, and other variables that have traditionally been projected externally to be input into the forecasting process.  相似文献   
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