Dynamic relocation of databases through networks, or database migration, will soon become a powerful standard database operation effectively using recent advances in broadband networks. In our previous work, a transac...
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The U.S. Navy recently conducted an analysis of alternatives (AOA) to set the stage for determining the characteristics and acquisition strategy for its next generation aircraft carrier. The platform design selected i...
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The U.S. Navy recently conducted an analysis of alternatives (AOA) to set the stage for determining the characteristics and acquisition strategy for its next generation aircraft carrier. The platform design selected is expected to be in service throughout the 21st century. The parameters under consideration for change in the new carrier design lie in the areas of propulsion and electric power generation, aviation, survivability, service life, and total ownership cost (TOC) reduction. The issue of affordability is paramount This paper focuses on the need for the programmanagement office and its supporting cost analysis staff to understand the life cycle cost (LCC) of the existing and proposed future aircraft carriers and to then translate these LCC's into meaningful information for cost-conscious decision making. The challenge is to relate the LCC in terms the key decision-makers and the engineering team can use to satisfy their respective roles. Thus, it is necessary to translate the results of the given ship design alternative LCC's into the paradigms of the respective stakeholders: Fleet User (operators of aircraft carriers) Ship Designers (translators of the fleet operator requirements) program Sponsors (providers of the funding resources) programmanagement Office, Ship builder and Supporting Industry (executors of the acquisition and construction of the ship) Navy and OSD decision-makers (overseers of program execution) The paper describes the aircraft carrier LCC breakdown structure that has resulted, in part, from a recent navy/shipbuilder integrated product team effort to capture total ownership costs. The structure has been used in the AOA as a tool to identify cost drivers and to add the time element to the cast equation in order to perform return on investment and program affordability analysis. The expanded ship work breakdown structure (ESWBS) has emerged as the central backbone of the cost work breakdown for AOA work. The ESWBS structure is a natural
The authors discuss multimedia data communications using the Internet from the standpoint of providing services, and propose a cost model based on multilevel complex objects for the purpose of responding to the variou...
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The purpose of this article is to formulate and solve a shortest loop problem associated with the design of material flow handling systems in factories. The problem is formulated as an Integer Linear program (ILP) ini...
A prototype system was developed to test the applicability of a dualmethod information-filtering model for filtering e-mail messages: content-based filtering and sociological filtering implemented with user stereotype...
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It is well known that even a single soil shows different mechanical properties with variation in any of many influencing factors. Among these, the density of soil is a most important factor in many geotechnical proble...
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It is well known that even a single soil shows different mechanical properties with variation in any of many influencing factors. Among these, the density of soil is a most important factor in many geotechnical problems such as subsidence of grounds, stability of soil structures and liquefaction potential of sandy soils. Density is a key to reliable answers. In this study some 80 granular materials were used, and triaxial specimens with several relative densities were prepared;a series of conventional drained triaxial compression tests were conducted on the specimens. From experimental results, the dependency of deformation-failure behaviors of sands on relative density was comparatively examined, and the degree of relative density dependency was evaluated by the indices introduced in this study. The influence of primary properties, such as density, hardness, and shape and size of grains, on the degree of relative density dependency is discussed, as a subject of this study. It was found that the degree of relative density dependency is variable with primary properties. The degree of relative density dependency can be estimated from some index properties;void ratio extent (emax-emin) was selected as a promising parameter for evaluating the relative density dependency of deformation-failure behaviors of sands.
The mechanical properties of sands change notably with a variation of confining stress. In some geotechnical problems, such as the bearing capacity problem of shallow foundations on sand ground, the confining stress d...
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The mechanical properties of sands change notably with a variation of confining stress. In some geotechnical problems, such as the bearing capacity problem of shallow foundations on sand ground, the confining stress dependency of sand mechanical behavior plays an important role as a stress level effect. In this study deformation-failure behaviors of some 80 granular materials with various primary properties were observed in a series of triaxial compression tests covering a range from low to medium high confining stresses. From experimental results, the dependency of the deformation-failure behaviors of sands on confining stress was comparatively examined, and the degree of confining stress dependency was evaluated by the indices introduced in this study. The influence of primary properties, such as density, hardness, shape and size of grains, on the degree of confining stress dependency is the main subject of this study. From test results, it was found that the mechanical properties of sands vary markedly with a change in confining stress, and the degree of confining stress dependency varies with the primary properties. The degree of confining stress dependency can be estimated from some index properties;void ratio extent (emax-emin) was selected as a promising parameter for evaluating the confining stress dependency of the deformation-failure behaviors of sands.
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