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991.
Andrew Ripanti 《电子与电脑》2004,(10):109-112,114
TPs2383A是一种适用于以太网供电(PoE)的电源供电设备电源管理器(PSEPM).其根据IEEE规范802.3af能够管理多达8个端口,可实现端口控制和数据采集,并能通过标准的I2C串行接口总线与主机控制器进行通信.TPS2383A是TI PSEPM系列器件中推出的第二款产品,在内核或原TPS2383器件上提供了各种改进,实现了更高的灵活性及易用性.本文将讨论具体的修改方法,并介绍这些修改对完整的、符合规范的PsE或中型系统(mid-span system)实施的影响. 相似文献
992.
Eckerman David A.; Lundeen Christine A.; Steele Andrew; Fercho Heather L.; Ammerman Tammara A.; Anger W. Kent 《Canadian Metallurgical Quarterly》2002,7(4):313
A tenet of behavioral education is that interactive training produces superior retention compared with reading. However, this has not often been directly tested and never with practical occupational information in working adults. Adults from diverse occupational backgrounds learned the principles of proper respiratory protection presented (a) in a book, (b) on a computer monitor, (c) through interactive computerized training consisting of textual information and illustrative pictures followed by quizzes and feedback, or (d) passively viewing the information and quizzes in Condition c on a computer monitor. Interactive training produced significantly more correct test answers at immediate posttraining, 1 week, and 2 months. This study demonstrated the superiority of interactive training for teaching occupational safety and health information in working adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
The influence of CS-US interval on several different indices of learning in appetitive conditioning.
Four experiments examined the effects of varying the conditioned stimulus-unconditioned stimulus (CS-US) interval (and US density) on learning in an appetitive magazine approach task with rats. Learning was assessed with conditioned response (CR) measures, as well as measures of sensory-specific stimulus-outcome associations (Pavlovian-instrumental transfer, potentiated feeding, and US devaluation). The results from these studies indicate that there exists an inverse relation between CS-US interval and magazine approach CRs, but that sensory-specific stimulus-outcome associations are established over a wide range of relatively long, but not short, CS-US intervals. These data suggest that simple CR measures provide different information about what is learned than measures of the specific stimulus-outcome association, and that time is a more critical variable for the former than latter component of learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Abdullah M Assiri Bakri I Yousuf J Margaret Woodhouse Andrew J Quantock Paul J Murphy 《Contact lens & anterior eye》2006,29(2):75-79
Here, we describe a case in which A-scan ultrasound biometry was used to differentially diagnose the cause of reduced vision in a patient with keratoconus. A patient with keratoconus presented with reduced visual acuity in one eye, not improvable above 6/18 with specialist keratoconus contact lens fitting. This monocular amblyopia was attributed to previous anisometropic ametropia by the use of ultrasound biometry. The report demonstrates the usefulness of ultrasound biometry in the detection of amblyopia in circumstances in which a previous assessment of amblyopia is not possible. This information will impact upon decisions made for the future clinical management in this case, especially if vision deteriorates so that a corneal graft is required. 相似文献
995.
996.
Laura E. Briand Jih-Mirn Jehng Laura Cornaglia Andrew M. Hirt Israel E. Wachs 《Catalysis Today》2003,78(1-4):257-268
The present work investigates the number and nature of the surface active sites, selectivity and turnover frequency towards methanol selective oxidation of a series of bulk metal vanadates. The catalysts were synthesized through an organic route and characterized by laser Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and specific surface area analysis (BET). The number of surface active sites (Ns) was determined by measuring the concentration of surface methoxy species adsorbed on the catalysts exposed to an atmosphere of 2000 ppm of methanol in helium at 100 °C. The specific activity values (TOFs) were calculated by normalizing the methanol oxidation reaction rate by the number of surface active sites probed by methanol chemisorption. The comparison of the methanol oxidation products distribution from bulk metal vanadates, pure V2O5 and corresponding metal oxides (NiO, MnO, etc.) strongly suggests that the metal vanadate catalysts consist of only surface vanadium oxide sites. The comparison of the TOF values demonstrated that bulk metal vanadates possess similar activity to monolayer vanadium oxide supported catalysts and are more active than bulk metal molybdates for methanol selective oxidation. Moreover, bulk metal vanadates are as active and selective as the commercial MoO3/Fe2(MoO4)3 catalysts at high methanol conversion. 相似文献
997.
Gray Nicola S.; Hill Charlotte; McGleish Andrew; Timmons David; MacCulloch Malcom J.; Snowden Robert J. 《Canadian Metallurgical Quarterly》2003,71(3):443
The efficacy of the Historical, Clinical, and Risk Management Scales (HCR-20; C. D. Webster, D. Eaves, K. S. Douglas, & A. Wintrup, 1995), Psychopathy Checklist--Revised (PCL-R; R. D. Hare, 1991), Beck Hopelessness Scale (BHS; A. T. Beck, A. Weissman, D. Lester, & L. Trexler, 1974), and Brief Psychiatric Rating Scale (BPRS) to predict violence and self-harm in 34 institutionalized mentally disordered offenders was assessed. Both the HCR-20 and BPRS were strong predictors of violence whereas the PCL-R had moderate predictive ability. BHS was the only variable predictive of self-harm. Although risk assessment measures were successful at predicting in-patient violence, a clinical measure of mental state was at least as effective in these mentally disordered offenders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Andrew James Jacobs 《Journal of Urban Affairs》2002,24(2):175-196
In spite of Japan’s economic slowdown during the 1990s, major cities in Aichi Prefecture have continued to thrive. Nevertheless, these, and others in Japan, have largely been ignored by Western scholars as successful models of how to maintain vibrant cities elsewhere. As a result, little has been written in English, and few lessons have been learned in the U.S. from urban planning efforts in Japan. From literature research, field observations, and qualitative interviews with 40 local land use and economic development planners in the prefecture, this article chronicles how well integrated national, prefectural, and municipal development planning, supportive public policies, and corporate commitment have produced thriving major cities in Aichi, Japan. 相似文献
999.
Benight Charles C.; Antoni Michael H.; Kilbourn Kristin; Ironson Gail; Kumar Mahendra A.; Fletcher Mary Ann; Redwine Laura; Baum Andrew; Schneiderman Neil 《Canadian Metallurgical Quarterly》1997,16(3):248
The importance of coping self-efficacy (CSE) appraisals on psychological and physiological functioning for HIV seropositive patients facing a severe environmental stressor was tested comparing 37 HIV-infected gay men and 42 healthy male control participants following Hurricane Andrew. Results suggested that greater levels of CSE were related to lower emotional distress and posttraumatic stress disorder (PTSD) symptoms in both groups. In addition, greater CSE was associated with lower norepinephrine to cortisol ratios in the HIV group but not in the healthy control group. Results are discussed in relation to the coping process for HIV-infected individuals specifically and chronically ill populations in general who face severe environmental stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Design for Stream Restoration 总被引:2,自引:0,他引:2
F. Douglas Shields Jr. Ronald R. Copeland Peter C. Klingeman Martin W. Doyle Andrew Simon 《Canadian Metallurgical Quarterly》2003,129(8):575-584
Stream restoration, or more properly rehabilitation, is the return of a degraded stream ecosystem to a close approximation of its remaining natural potential. Many types of practices (dam removal, levee breaching, modified flow control, vegetative methods for streambank erosion control, etc.) are useful, but this paper focuses on channel reconstruction. A tension exists between restoring natural fluvial processes and ensuring stability of the completed project. Sedimentation analyses are a key aspect of design since many projects fail due to erosion or sedimentation. Existing design approaches range from relatively simple ones based on stream classification and regional hydraulic geometry relations to more complex two- and three-dimensional numerical models. Herein an intermediate approach featuring application of hydraulic engineering tools for assessment of watershed geomorphology, channel-forming discharge analysis, and hydraulic analysis in the form of one-dimensional flow and sediment transport computations is described. 相似文献