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排序方式: 共有769条查询结果,搜索用时 15 毫秒
61.
Price W.W. Hargrave A.W. Hurysz B.J. Chow J.H. Hirsch P.M. 《Power Systems, IEEE Transactions on》1998,13(3):768-774
This paper presents the results of applying the EPRI Dynamic Equivalencing Program to a large-scale system test case of the New York Power Pool. The effects of coherent generator selection, network reduction, generator aggregation, and generator modeling on the accuracy of the reduced models are investigated 相似文献
62.
NROM: A novel localized trapping, 2-bit nonvolatile memory cell 总被引:1,自引:0,他引:1
Eitan B. Pavan P. Bloom I. Aloni E. Frommer A. Finzi D. 《Electron Device Letters, IEEE》2000,21(11):543-545
This paper presents a novel flash memory cell based on localized charge trapping in a dielectric layer and on a new read operation. It is based on the storage of a nominal ~400 electrons above a n+/p junction. Programming is performed by channel hot electron injection and erase by tunneling enhanced hot hole injection. The new read methodology is very sensitive to the location of trapped charge above the source. This single device cell has a two physical bit storage capability. The cell shows improved erase performances, no over erase and erratic bit issues, very good retention at 250°C, and endurance up to 1M cycles. Only four masks are added to a standard CMOS process to implement a virtual ground array. In a typical 0.35 μm process, the area of a bit is 0.315 μm2 and 0.188 μm2 in 0.25 μm technology. All these features and the small cell size compared to any other flash cell make this device a very attractive solution for all NVM applications 相似文献
63.
C. Collado G. GoglioG. Demazeau A.S. BarrièreL. Hirsch M. Leroux 《Materials Research Bulletin》2002,37(5):841-848
GaN microcrystallites have been prepared by a solvothermal process. The influence of the synthesis temperature on the crystallinity of the resulting GaN has been studied on three samples, prepared at 400, 600 and 800°C in the same pressure conditions (150 MPa) and duration (6 h). The resulting powders were characterized by several techniques: X-ray diffraction to evaluate the reaction rate, scanning electron microscopy (SEM) to determine the morphology and size of the microcrystallites and photoluminescence to evaluate the quality of the powders. 相似文献
64.
65.
Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States 总被引:3,自引:0,他引:3
RC Lawrence CG Helmick FC Arnett RA Deyo DT Felson EH Giannini SP Heyse R Hirsch MC Hochberg GG Hunder MH Liang SR Pillemer VD Steen F Wolfe 《Canadian Metallurgical Quarterly》1998,41(5):778-799
OBJECTIVE: To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain). METHODS: The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020. RESULTS: Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form of arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected. CONCLUSION: Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population. 相似文献
66.
67.
BT Hirsch 《Canadian Metallurgical Quarterly》1997,(336):33-41
Economic theory and evidence indicate that workers, employers, and healthcare personnel respond to the incentives built into state workers' compensation systems. Although empirical studies cannot provide precise estimates of the quantitative effects resulting from specific policy changes, research is useful in evaluating the qualitative effects of alternative policies. Studies show that workers' compensation claims are higher the more generous the level of benefits, the shorter the waiting period, and the more readily available is information on benefits to workers. States that decrease real benefit levels and lengthen the period required before workers are compensated for lost earnings can constrain future growth in workers' compensation costs, while continuing to provide partial compensation for workers with the most serious injuries. The most difficult problem facing policymakers is to design and implement reforms that take into account what are often the incompatible incentives of workers, employers, and medical care providers. 相似文献
68.
Eric Mendelsohn (2005) emphasizes the value of analysts' learning from patients, optimal ways of working with them psychoanalytically. He exhibits a healthy skepticism about traditional methods of learning to be a psychoanalyst, with particular caution about identifying with strong teachers or all-too-clear systems of thought. He fears this may inadvertently create a kind of fundamentalism and a parallel loss of analytic spontaneity. The author agrees with much of Mendelsohn's thesis but has some concern about going too far in the direction of promoting spontaneity, as this ethos too can reflect an inclination to idealize charismatic teachers who specialize in breaking the rules. He suggests that an emphasis on analytic spontaneity is best acquired after some reasonable period of working as at least a somewhat reserved and cautious young analyst. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Stoltenberg Scott F.; Hirsch Jerry; Berlocher Stewart H. 《Canadian Metallurgical Quarterly》1995,109(1):85
The behavior–genetic analysis of Drosophila melanogaster with geotactic performance as the phenotype is an ideal model system with which to investigate the complex relations between heredity and behavior. As part of a long-term, 38-year study, we report 4 experiments that identify and analyze trait correlations in the selected high- and low-geotaxis lines. We performed F2 correlational analyses and backcrosses to examine 3 types of correlations: (a) genotype–genotype (alcohol dehydrogenase [Adh]–amylase [Amy]), (b) genotype–phenotype (Adh and Amy–geotaxis), and (c) phenotype–phenotype (mate preference–geotaxis). Only the Adh-geotaxis correlation survived meiosis and reappeared in the F2 generation, which indicates a genotype-phenotype correlation, whereas the others did not. The importance of hybrid correlational analysis to the behavior–genetic analysis of a species is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献