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21.
A technique is described for using the advantages of a social systems approach when working with elderly persons in psychiatric distress. The technique is based on the assumption that the solution to a variety of human predicaments lies within the collective instrumental and affective resources of the client's social network. The vehicle for accomplishing this objective is the "Network Session" during which a mental health professional meets with the elderly person and members of his/her social network to help resolve the difficulty. A case report demonstrating use of the technique is included. 相似文献
22.
Bill Schuh 《电子设计技术》2006,13(10):174-174,176,178,181
基于现场可编程门阵列(FPGA)核心的实施体现了先进的现代航空电子设计方法。这项技术具有多种优势,如废弃组件管理、降低设计风险、提高集成度、减小体积、降低功耗和提高故障平均间隔时间(MTBF)等,吸引着用户将原来的系统转移到此项技术。MIL-STD-1553的市场可能随着这种趋势而繁荣起来;事实上,某些客户已经觉得这项技术的实施有点姗姗来迟。MIL-STD-1553核心带来了多种好处,它代表着彻底告别了ASIC传统。FPGA中加入一项知识产权核心,就获得了一种与众不同的特性,而成为一个非常专业的高级子系统。这为增强MIL-STD-1553的设… 相似文献
23.
Twenty-four Holstein heifers were fed grain and alfalfa hay ad libitum for accelerated growth from 91 kg body weight until verification of pregnancy (Treatment A). Grain then was deleted until near time of freshening. They were bred at second estrus if they weighed at least 305 kg. An additional 24 heifers were fed a conventional roughage ration to allow a growth rate corresponding to the Beltsville growth standard and were bred when 15 to 16 mo of age (Treatment S). Observations were of growth rate, reproductive and productive performance, and length of herd life under normal culling.The A heifers gained 38% faster to 364 kg body weight (1.1 versus .8 kg/day). Average weights and ages were first estrus 275 kg, 8.3 mo (A), 288 kg, 10.2 mo (S); first breeding 319 kg, 9.6 mo (A), 392 kg, 16.8 mo (S); and first calving 560 kg, 19.7 mo (A), 26.9 mo (S). Differences in body dimensions at given weights were negligible. Treatment effects on dystocia were inconclusive. Lactation number, numbers of animals milked 100+ days, and average milk yields (kg) were: 1st lactation 24, 4436 (A), 22, 5415 (S); 2nd–22, 5295 (A), 18, 5903 (S); 3rd–12, 6278 (A), 10, 6407 (S); 4th–6, 7181 (A), 5, 5269 (S). Mean accumulative milk yields per animal to 36 mo of age were 7173 (A) and 4853 kg (S). Accelerated growth and early breeding did not affect herd life. 相似文献
24.
The order of an electromagnetics algorithm or code is defined by the rate at which the CPU time, and memory requirements CCPU=O(fα) and Cm=O(fβ ), respectively-grow with frequency. Knowledge of this information helps in the prediction of computer-run times and memory requirements for problems of interest. This paper presents a methodology for determining the computational and memory orders of a code. These results are presented for a finite-volume time-domain (FVTD) code and for a method-of-moments (MoM) code. Computer-resource requirements are plotted for computer runs that calculate the bistatic radar cross section (RCS) for spheres of different electrical sizes, within a set error level from the Mie-series solution. These plots are used to calculate the computational and memory orders of the codes 相似文献
25.
The fabrication of multilayer assemblies from polymeric compounds is an important tool for precise control of film architecture on the nanoscale. In this report, a general, novel approach for the preparation of well‐defined polymeric multilayers is described. To achieve this, sulfonyl‐azide group containing polymers are first generated and deposited as thin films onto solid (organic) substrates. Upon thermal activation, the system crosslinks and binds to the substrate via C–H bond insertion. Through step‐and‐repeat procedures, multilayer assemblies are then generated where all the individual layers are linked to each other. As the assembly process does not require any specific molecular interactions, the described process represents a general strategy to generate tailor‐made multilayer surface coatings with wide range of film thickness and composition. 相似文献
26.
Inverse-synthetic-aperture-radar (ISAR) images of radar targets are useful for target identification, visualization, and the analysis of scattering centers. The major advantage of bistatic over monostatic-ISAR imaging is the reduction, in the number of computed incident angles, from hundreds to one. This advantage has already been demonstrated for a physical theory of diffraction (PTD) code, XPATCH. The bistatic-imaging technique can be extended to scattering data obtained from any time-accurate or iterative method, including low-frequency algorithms. This paper presents images from data obtained with a finite-volume time-domain (FVTD) code. It also provides relations between (1) the range and resolution of the bistatic scattering data in the Fourier domain, and (2) the pixel resolution and image extent in the physical domain for the down-range and cross-range directions. A tapering function is applied in the Fourier domain, to dampen ringing effects. Results are shown for a trapezoidal plate, a cone-sphere, and a square-aperture cavity 相似文献
27.
Copper‐based shape memory alloys (SMAs) exhibit excellent shape memory properties in single crystalline form. However, when they are polycrystalline, their shape memory properties are severely compromised by brittle fracture arising from transformation strain incompatibility at grain boundaries and triple junctions. Oligocrystalline shape memory alloys (oSMAs) are microstructurally designed SMA structures in which the total surface area exceeds the total grain boundary area, and triple junctions can even be completely absent. Here it is shown how an oligocrystalline structure provides a means of achieving single crystal‐like SMA properties without being limited by constraints of single crystal processing. Additionally, the formation of oSMAs typically involves the reduction of the size scale of specimens, and sample size effects begin to emerge. Recent findings on a size effect on the martensitic transformation in oSMAs are compared and a new regime of heat transfer associated with the transformation heat evolution in these alloys is discussed. New results on unassisted two‐way shape memory and the effect of loading rate in oSMAs are also reported. 相似文献
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In the new agent 3-(5-tetrazolyl)penam, hereafter referred to as CP-35,587, the carboxyl function at C3 in the penicillin nucleus has been replaced with the 5-tetrazolyl moiety. Marked changes in spectrum and resistance to gram-negative beta-lactamases, particularly with regard to Klebsiella pneumoniae isolates, were conferred by this modification. The anti-Klebsiella activity clearly distinguishes the antibacterial spectrum of CP-35,587 from any known broad-spectrum penicillin. Compared to orally active cephalosporins, the spectrum advantage of CP-35,587 encompasses Enterobacter, Serratia marcescens, Citrobacter, Providencia, Haemophilus influenzae, and Streptococcus faecalis, both in vitro and in murine infections produced by many of the above-named microorganisms. Thus, CP-35,587 combines and extends the antibacterial activity of broad-spectrum penicillins and orally active cephalosporins. 相似文献