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991.
992.
In this article Mr. Coppie calls attention to the current taxpayer's revolt sweeping the country and points to its potentially ominous meaning for cities. He believes the revolt is motivated by a concern for the need for greater accountability for performance in the public sector than actual tax burdens or tax increases. He says most cities are in need of substantial additional intergovernmental assistance and this will be very difficult to come by in the near future. He says cities must give a high priority to comprehensive financial management and that there will be a relationship between higher levels of government responding to the demands for fiscal assistance and the ability of cities to manage their resources effectively and efficiently. Specifically, Mr. Coppie discusses the following components of financial management: Multi-Year Financial Planning; Issue Identification and Analysis; Productivity Measures; Methods of Disclosure; Training Programs; and A Management Information System. Mr. Coppie is frank to point out that financial management by itself will not solve a city's financial needs. It is, however, an important element in improving a city's credibility and may make it easier to get intergovernmental assistance.  相似文献   
993.
994.
Historical developments regarding the realization of the importance of reliable thermophysical properties data in engineering applications are presented. The events leading to the establishment of the Symposium on Thermophysical Properties in 1959 and the accomplishments of the symposia series since then are discussed. Contributions of the National Bureau of Standards to the thermophysical properties field are described.Welcoming address presented at the Ninth Symposium on Thermophysical Properties, June 24–27, 1985, Boulder, Colorado, U.S.A.  相似文献   
995.
996.
997.
This paper draws attention to the basic principles governing reflections in uniform Bragg reflectors (BR) when measured employing optical low coherence reflectometry (OLCR) technique. Using computations based on transfer matrix method (TMM), we first showed a strong spectral dependence of Bragg reflectograms on an OLCR probe spectrum. Later, this dependence is exploited to evaluate, for the first time, the coupling coefficient κ of a Bragg grating in a distributed Bragg reflector (DBR) laser on InP  相似文献   
998.
Si/SiGe n-type modulation-doped field-effect transistors grown on a very thin strain-relieved Si/sub 0.69/Ge/sub 0.31/ buffer on top of a Si(100) substrate were fabricated and characterized. This novel type of virtual substrate has been created by means of a high dose He ion implantation localized beneath a 95-nm-thick pseudomorphic SiGe layer on Si followed by a strain relaxing annealing step at 850/spl deg/C. The layers were grown by molecular beam epitaxy. Electron mobilities of 1415 cm/sup 2//Vs and 5270 cm/sup 2//Vs were measured at room temperature and 77 K, respectively, at a sheet carrier density of about 3/spl times/10/sup 12//cm/sup 2/. The fabricated transistors with Pt-Schottky gates showed good dc characteristics with a drain current of 330 mA/mm and a transconductance of 200 mS/mm. Cutoff frequencies of f/sub t/=49 GHz and f/sub max/=95 GHz at 100 nm gate length were obtained which are quite close to the figures of merit of a control sample grown on a conventional, thick Si/sub 0.7/Ge/sub 0.3/ buffer.  相似文献   
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