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51.
We use retrodictive quantum theory to describe cavity field measurements by successive atomic detections in the micromaser. We calculate the state of the micromaser cavity field prior to detection of sequences of atoms in either the excited or ground state, for atoms that are initially prepared in the excited state. This provides the POM elements, which describe such sequences of measurements. 相似文献
52.
JOHN J. CHIN 《Journal of Urban Affairs》2009,31(4):431-460
ABSTRACT: In addition to providing a wide range of essential services in local communities, service‐providing nonprofit organizations play an important role in shaping de facto local social policy through their participation in community‐based planning processes that guide or determine the distribution of federal funding for health and social services. This social policy role has become increasingly important in the United States as the federal government continues to privatize health and human services through providing grant funds to states and cities that are ultimately used to support local nonprofit health and social service organizations. The important role of service‐providing nonprofits in shaping local social policy has been understudied, as most studies on nonprofits and policy‐making focus on citizen advocacy organizations and their lobbying and protest activities, primarily at the national level. This study uses the case of the New York HIV Planning Council to address this gap in the literature, highlighting the benefits and pitfalls of an urban community planning process dominated by service providers from local nonprofit social service organizations whose own organizations are affected by the planning group's decisions. Factors that contributed to nonprofit providers' dominance as well as factors that limited their self‐interested behavior are reviewed. The relationship between the HIV nonprofit service system and the AIDS social movement is explored in light of theory on new social movements to help explain why nonprofit providers were sometimes able to promote attentiveness to the general public good while also advocating for their more self‐interested organizational needs. 相似文献
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JOHN L. BURBIDGE 《国际生产研究杂志》2013,51(3):429-442
Generations of managers in industry and of academics in universities, have been intrigued by the problem of how to plan, and more recently how to automate the scheduling of the operations needed to make parts, on the machines and other work centres in a factory. Today, with one possible exception (OPT) (Goldratt 1980), we are no nearer a reliable solution than we were 100 years ago. Early attempts at centralized operation scheduling, were based on Gantt charts or planning boards. Later solutions have used the computer. They all face the problems that with traditional forms of organization, there is a very large number of constraints which affect the solution, and that if a machine-breakdown, absent worker, material shortage or other disaster makes it necessary to change the schedule, it is generally impossible to revise it to suit the new situation quickly enough to keep the factory running. The usual solution is: ‘Tell the foreman to do the best he can’. This paper submits that the introduction of group technology (GT), coupled with period batch control (PBC), so simplifies the problem, that with minor analytical assistance the GT group foremen can do their own operation scheduling, more reliably and cheaply than it can be done by the computer. 相似文献
55.
This paper presents a fuzzy algorithmic approach to the construction of composite indices. The method uses a fuzzy analytic translation of a linguistic definition of the composite index, where the definition involves more primary concepts for which scales already exist. An application to the construction of a functional limitation index is presented. Comparisons between the fuzzy algorithmic approach and a more standard, tabular approach are also shown. The results suggest that the fuzzy algorithmic approach yields essentially the same index with less effort and some conceptual advantages. 相似文献
56.
ALBA L. RAMASWAMY JOHN GLASS PHIL RENN PHIL STURGILL 《Journal of Energetic Materials》2013,31(4):231-250
The transformation of a boron-containing pyrotechnic mix to a “ceramic” vitreous-like material by the impingement of an electron beam on a boron-barium chromate pyrotechnic, in a scanning electron microscope, is reported. The thickness of the “ceramic”-like material is ×250 the penetration depth for the electron beam and indicates that a self-sustaining chemical reaction was induced by interaction of the energetic material with the electron beam at temperatures well below the mix's ignition temperature of over 1000?°C. This links with earlier observations on the low-temperature liquefaction of boron to boron suboxides in an electron microscope. 相似文献
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The possibility of using frozen hoki to make surimi was investigated. At intervals, fish were thawed under controlled conditions and gels were then made from minces of the flesh. Both puncture and torsion tests showed the quality of gels declined with duration of storage of frozen hoki. This decline was matched by a decrease in pH and an increase in formaldehyde concentration in the frozen flesh. The data suggest a land-based surimi plant could not be operated outside the harvesting season to any appreciable extent using frozen hoki stored at -29°C. 相似文献
59.
Optimization of Blanching for Crispness of Banana Chips Using Response Surface Methodology 总被引:1,自引:0,他引:1
Whole green bananas were blanched in water at 50, 60, 70, 80, 90, and 100°C for 2, 15, and 30 min using a factorial design then peeled, sliced and fried in oil to make chips. Crispness was measured using a bending-snapping test in the TA.XT2 Texture Analyzer. Significant interactions were found between blanch time and temperature and crispness of chips. A second experiment was then performed using a central composite design and blanch temperatures from 41.7 to 98.3°C. Response surface analysis predicted that crispiest chips should be produced at blanching conditions of 69°C and 22 min. 相似文献
60.