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991.
B. V. Kuteev V. Yu. Sergeev V. A. Belopol’sky V. M. Timokhin R. Burhenn 《Technical Physics Letters》2003,29(4):302-304
Experiments performed on a Wendelstein 7-AS stellarator revealed asymmetry of the cloud of an ablating carbon pellet. The cloud is elongated in the direction of large radius toward stronger fields, that is, opposite to the direction expected due to the toroidal drift. In order to study the effect in more detail, the three-dimensional structure of the cloud was analyzed by computer tomography. The results confirmed asymmetry of the cloud. This asymmetry is related to a drift flow existing in the plasma and directed along large radius toward stronger fields. The drift velocity is numerically estimated at ~300 m/s. 相似文献
992.
Sood Johanna R.; Cisek Edward; Zimmerman Joan; Zaleski Ellen H.; Fillmore Herbert H. 《Canadian Metallurgical Quarterly》2003,48(1):44
Objective: To replicate and extend P. A. Lichtenberg and colleagues' (1996) cross-disciplinary intervention to improve physical and mental health among older adults. Participants: 14 depressed older adults (6 treatment, 8 control). Setting: The short-term rehabilitation unit of an urban nursing home. Intervention: Occupational therapists were trained to treat depression using pleasant events and cognitive-behavioral therapies. Outcome Measures: Geriatric Depression Scale, the Short Form-12, and the Multi-Level Assessment Instrument: Activities of Daily Living. Results: No significant group differences were found in physical or mental health. However, more control group members (75%) than treatment group members (33%) were depressed at study completion. Conclusions: The treatment of depressive symptoms can be integrated with a nonmental health treatment modality. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
993.
Drew Michael R.; Yang Cynthia; Ohyama Tatsuya; Balsam Peter D. 《Canadian Metallurgical Quarterly》2004,30(3):163
Three experiments investigated the effects of varying the conditioned stimulus (CS) duration between training and extinction. Ring doves (Streptopelia risoria) were autoshaped on a fixed CS-unconditioned stimulus (US) interval and extinguished with CS presentations that were longer, shorter, or the same as the training duration. During a subsequent test session, the training CS duration was reintroduced. Results suggest that the cessation of responding during an extinction session is controlled by generalization of excitation between the training and extinction CSs and by the number of nonreinforced CS presentations. Transfer of extinction to the training CS is controlled by the similarity between the extinction and training CSs. Extinction learning is temporally specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Boundary objects are a critical, but understudied, theoretical construct in CSCW. Through a field study of aircraft technical
support, we examined the role of boundary objects in the practical achievement of safety by service engineers. Their resolution
of repair requests was preserved in the organization’s memory via three compound boundary objects. These crystallizations
did not manifest a static interpretation, but instead were continually reinterpreted in light of meta-negotiations. This suggests
design implications for organizational memory systems which can more fluidly represent the meta-negotiations surrounding boundary
objects. 相似文献
995.
Robert R. Gillies Jayne Brim Box Jürgen Symanzik Eli J. Rodemaker 《Remote sensing of environment》2003,86(3):411-422
Impervious surface area (ISA) was derived for a period from 1979 to 1997 from Landsat MSS and TM data for the Line Creek watershed that lies to the south of the city of Atlanta, GA. The change in ISA is presented as an ecological indicator to examine the cumulative water resource impacts on mussel population in three sub-watersheds of Line Creek—namely, Line, Flat, and Whitewater creeks. The satellite analysis shows that ISA expansion occurred substantially from 1987 to 1997 and is predominantly in industrial, commercial, and shopping center (ICS) complexes but also in smaller lot-size residential development. Evidence of mussel habitat degradation is indicated and loss of species (in the region of 50 to 70%) is present in areas where ISA expansion is observed—specifically in ICS complex development in and around Peachtree City that drains directly into the Line and Flat creeks. This is in marked contrast to Whitewater Creek where overall development of ISA is less and no major loss of mussel species is observed. 相似文献
996.
Among engineers and scientists, MATLAB is one of the most popular computational packages. Part of MATLAB's popularity stems from its simple, yet sophisticated, graphics capabilities. While basic plots are relatively easy to obtain, specialized plots require a little more effort to produce. This article introduces MATLAB's Handle Graphics, which provides a mechanism to fully control and customize graphics objects in MATLAB. With a basic understanding of Handle Graphics, users can produce plots that meet the unique needs and quality standards commonly required by the profession, several examples are presented to illustrate the concepts. 相似文献
997.
The testing and quality assurance of the Motif 1.0 graphical user-interface software are described. The testing goals, which fell into three general categories (code coverage, defect-density, and defect-arrival rate), and a deliverable formal test suite are examined. The three phases of the testing process-evaluation, test development, and regression testing-and the tools used in testing are discussed 相似文献
998.
999.
Pent et al. (see ibid., vol.SAC-6, no.1, p.34-41, 1988) proposed a semianalytic method for performance evaluation of communication channels with a bandpass nonlinearity. This method is based on a decomposition of the composite signal at the output of the nonlinear device which leads to the definition of an equivalent nonlinearity. In Pent et al. such an equivalent model is evaluated via numerical integration. In the present comment it is shown that a suitable series expansion of the nonlinearity characteristic yields to an evaluation of the equivalent nonlinearity in closed form 相似文献
1000.