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41.
Investigated compliance with homework directives in counseling in 61 clients (aged 21+ yrs), with the cooperation of 18 post-master's degree counselors in a community counseling agency for adults. Compliance was examined as a function of counselor variables, client variables, and therapy variables, using rankings of counselor ability and skills, a rating of cases, and data on homework assignments. Neither counselor ability nor specific counseling skills were related to client compliance. Initial severity of client problems was related to outcome but not to compliance. Clients who remained in counseling had better compliance than those who terminated early. Whether clients presented career or personal/emotional problems was unrelated to compliance. Therapy variables that predicted compliance included assignments given early in counseling, a history of compliance, and whether counselors checked their client's attitude about homework and did not stress their own status. It is suggested that variables associated with the conduct of counseling more strongly influence compliance with homework than do either counselor or client variables. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Cochlear frequency selectivity in lower vertebrates arises in part from electrical tuning intrinsic to the sensory hair cells. The resonant frequency is determined largely by the gating kinetics of calcium-activated potassium (BK) channels encoded by the slo gene. Alternative splicing of slo from chick cochlea generated kinetically distinct BK channels. Combination with accessory beta subunits slowed the gating kinetics of alpha splice variants but preserved relative differences between them. In situ hybridization showed that the beta subunit is preferentially expressed by low-frequency (apical) hair cells in the avian cochlea. Interaction of beta with alpha splice variants could provide the kinetic range needed for electrical tuning of cochlear hair cells.  相似文献   
44.
A six year old boy with an epicardial pacing lead since infancy presented with thoracic pain triggered by movement. The pain was thought to be musculoskeletal, but two weeks later he collapsed and died in ventricular fibrillation. Necropsy showed strangulation of the ventricular apex by the epicardial lead.  相似文献   
45.
The nonlinearities generated by wide-band, high-current photodetectors are discussed in the context of the performance of an externally modulated analog radio-frequency fiber-optic link. The quantitative impart of the detector's third-order intermodulation product intercept (IP3) on the link's spur-free dynamic range is analyzed. Waveguide p-i-n photodiodes were developed to specifically address these stringent IP3 goals. The IP3 was measured using a four laser heterodyne system resulting in an IP3 of 27 dBm measured at a center frequency of 20 GHz with 20 mA of de photocurrent. The authors believe that this is the highest photodetector IP3 reported to date at these operating conditions  相似文献   
46.
It argued that software engineering is about to reach a new stage, the reliability stage, that stresses customers' operational needs and that software-reliability engineering will make this stage possible. Software-reliability engineering is defined as the applied science of predicting, measuring, and managing the reliability of software-based systems to maximize customer satisfaction. The basic concepts of software reliability-engineering and the reasons why it is important are examined. The application of software-reliability engineering at each stage of the life cycle is described  相似文献   
47.
The measurement and analysis aspects of software reliability are described with the aim of providing software engineers and managers a sense of where and how software reliability measurements can be applied to their projects. Some background for understanding software reliability measurement is provided, and activities associated with measuring and analyzing software reliability are discussed in the context of the software product life cycle. The focus is on failures and the rate at which they occur. The thrust of reliability measurement and analysis is to specify what the customer needs in terms of reliability before a software product is built, to validate that these needs are met before delivery of the product to the customer, and to make sure that the customer's needs continue to be met after delivery  相似文献   
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The authors examine microwave landing system (MLS) ground equipment design considerations for achieving the requirements for Category III landing operations. Specifically addressed are accuracy, continuity of service, and integrity requirements. Accuracy near the touchdown region is achieved by providing adequate transmitter power, sufficiently small antenna beamwidth, low effective sidelobes (e.g. by introducing a degree of randomness in the dynamic sidelobes and by using a directive element pattern), and, in the azimuth antenna, by shaping the vertical pattern. High continuity of service is achieved by using a high-reliability design, through redundancy of critical elements, by providing an uninterruptible power supply, and by incorporating prealarm warnings. High integrity is achieved by providing an appropriate configuration of redundant monitors, a capability to verify monitor performance periodically, a high-reliability control circuit, and sufficiently independent implementation of transmitter, monitor, and control functions  相似文献   
50.
大型水轮发电机组轴系临界转速模拟试验研究   总被引:1,自引:2,他引:1  
针对大型水轮发电机组轴系临界转速难以实际测定的现实问题,从理论分析的角度出发,抓住水力机组轴系结构的基本特点,提出采用较为简单的模拟结构,试验研究水力机组轴系固有频率及其振型特征。初步研究结果已在理论分析和实际机组中得到验证。  相似文献   
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