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31.
Michael Bommer Fay Blair Gilbert Goodgion Victor Pease 《Computers, Environment and Urban Systems》1980,5(1-2)
This paper describes the development of a zero base budgeting process as part of an integral planning-budgeting-control system relating client needs with service programs. Particular attention is focused on designing, gaining acceptance for and implementing a new budgeting system for the human services agencies of a rural county government. The relationship of the zero base budgeting process to the client case management and evaluation system are explored. Problems encountered in implementing the system and an evaluation of the results are discussed. 相似文献
32.
Ionospherically propagated h.f. radio waves that have been backscattered from the sea can often be distinguished from those backscattered from land because of their different Doppler spectra. This characteristic has been exploited to generate an ionospheric radar map of the south-east United States from Boulder, Colo., by gating out the sea-scatter Doppler components. The agreement between the observed and actual land-sea boundaries is good. 相似文献
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34.
Hundreds of atomic frequency standards and precision crystal oscillators exist in remote locations throughout the continental U.S. that are synchronized through fairly complex and costly means. Today, however, an inexpensive synchronization system is available in the form of live television broadcasts by commercial networks. In precision and accuracy, the television method is comparable to the portable atomic clock and/or Loran-C, with average day-to-day differential delays less than 1?s. Based on the results of the tests presented here, the use of nearly any solid-state television receiver and a low-cost horizontal sync pulse generator can provide 10-?s synchronizations at all times. The operation of a TV line-10 timing system, including the circuitry of auxiliary equipment, is also included. This article gives about 1? years of substantiating data for the three major commercial networks (ABC, CBS, and NBC). There is also provision for synchronization with the NBS and/or USNO Coordinated Universal Time (UTC) scales through regularly published reports. 相似文献
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36.
Reactive hot-pressing of co-precipitated oxalates of Yttrium and Iron, under 6000–8000 psi, to a maximum temperature of 1100°C, produced high density specimens. Only the stooichiometric mixture (Fe/Y=1.66) produced some garnet phase. Off-stoichiometric specimens were mainly composed of orthoferrites. On annealing in air or oxygen at 1400°C, the orthoferrite phase was converted to the garnet phase (with excess Fe2O3 or Y2O3 in the lattice) with an accompanying increase in magnetic moment. 相似文献
37.
Matthew T. Martens Alexander J. Wall Greg G. Pyle Blair A. Wasylenko William A. Dew Robert H. Devlin Paul J. Blanchfield 《Journal of Great Lakes research》2014
Selective breeding of salmonid fishes for the purpose of commercial aquaculture has resulted in domesticated strains possessing a divergent physiological and behavioral phenotype from that of wild conspecifics. Freshwater production of rainbow trout (Oncorhynchus mykiss) has been occurring in regions of Lake Huron, Canada, for decades yet the growth and performance of domestic (aquaculture) versus wild (naturalized) strains are poorly understood. We conducted two trials to examine growth differences between size-matched wild and domestic strains of juvenile rainbow trout: (1) reared separately and fed to satiation; and (2) reared together and fed a reduced ration to induce competition. Additionally, we used bioenergetics models to assess strain-specific growth rates across a range of water temperatures (5, 10, 15 and 18 °C) as well as Lake Huron temperatures during the open-water season. Domestic rainbow trout showed a growth advantage throughout the 102 d trials, and by the end of the study had achieved a mass > two-fold that of the wild strain and had greater fork length, condition, and thermal growth coefficient (TGC) under both treatments. Rapid growth of domestic strain fish was achieved through the combination of enhanced feed consumption (by ~ 40%) and feeding efficiency (up to 60% lower feed conversion ratio) relative to wild fish. Divergence in growth rates between strains was most pronounced (> 3 ×) when modeled with Lake Huron open-water temperatures. We demonstrate that the growth and feed-conversion efficiency differ significantly between these two strains of rainbow trout under laboratory conditions, suggesting that differences could be even greater in nature. 相似文献
38.
The iron-chelating agent desferrioxamine now finds extensive use in the treatment and diagnosis of aluminum-related diseases in renal patients. We review the chemistry and pharmacokinetics of desferrioxamine in chelation therapy for patients on hemodialysis. 相似文献
39.
The formation of IrB2, IrB1.35, IrB1.1 and IrB monoboride phases in the Ir–B ceramic nanopowder was confirmed during mechanochemical reaction between metallic Ir and elemental B powders. The Ir–B phases were analysed after 90 h of high energy ball milling and after annealing of the powder for 72 h at 1050°C in vacuo. The iridium monoboride (IrB) orthorhombic phase was synthesised experimentally for the first time and identified by powder X-ray diffraction. Additionally, the ReB2 type IrB2 hexagonal phase was also produced for the first time and identified by high resolution transmission electron microscope. Ir segregation along disordered domains of the boron lattice was found to occur during high temperature annealing. These nanodomains may have useful catalytic properties. 相似文献
40.
Tae-Kyu Lee Bite Zhou Lauren Blair Kuo-Chuan Liu Thomas R. Bieler 《Journal of Electronic Materials》2010,39(12):2588-2597
Thermally cycled plastic ball grid array (PBGA) packages with full arrays of 196 solder joints after various preconditions were examined to observe the microstructure evolution of Sn-Ag-Cu solder joints during aging and thermal cycling, focusing on Sn grain orientation. Each PBGA package was polished to obtain a plan-view cross-section of every solder joint, and characterized using both polarized optical microscopy and orientation imaging microscopy (OIM). By OIM observations, distribution maps were obtained based on Sn crystal c-axis orientations. Each precondition showed a characteristic distribution related to the combined thermal aging and thermal cycling history. This study on Sn grain orientation using OIM provides further understanding about deformation and microstructure evolution processes that occur during thermal cycling, and the impact of isothermal aging as a precondition. 相似文献