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91.
Joseph Leu 《软件工程师》2006,(4):55-57
Silicon Valley is hom e to the m ostdynam ic industries in the C aliforniaeconom y .These industries —— thehigh-tech sector—— are driven by in-novation,and each new wave of inno-vation is usually led by cre ativeentrepreneurs starting new firm s.D uri… 相似文献
92.
Joseph J. Niemela 《Journal of Low Temperature Physics》1997,109(5-6):709-732
Liquid Helium II drops, of diameter 1 mm or less, are charged with positive helium ions and subsequently levitated by static
electric fields. Stable levitation was achieved for drops of order 100–150 micrometers in diameter. The suspended drops could
be translated to arbitrary positions within the levitator using additional superimposed DC electric fields, and also could
be made to oscillate stably about their average positions by means of an applied time-varying electric field. A weak corona
discharge was used to produce the necessary ions for levitation. A novel superfluid film flow device, developed for the controlled
deployment of large charged drops, is described. Also discussed is an adjustable electric fountain that requires only a field
emission tip operating at modest potentials, and works in both Helium I and Helium II. 相似文献
93.
Joseph W. Burley 《乙烯基与添加剂工艺杂志》1996,2(4):282-286
Both the European and USA markets for liquid mixed metal stabilizers have moved or are moving to cadmium-free products. Self-lubricating products now dominate demanding areas such as calendering and extrusion in the European marketplace while the USA market has produced higher efficiency products by other means. In both markets, the use of organic costabilizers has played a major role in the formulation of cadmium-free products. The merits of self-lubricating technology and a new class of patented pyrrolidines are discussed here. 相似文献
94.
95.
AG Heriot D Kumar V Thomas M Young J Pilcher AE Joseph 《Canadian Metallurgical Quarterly》1998,85(12):1713-1715
BACKGROUND: The use of fine-needle aspiration cytology (FNAC) in the diagnosis of colonic lesions was investigated. METHODS: Some 22 patients (median age 71 years) with a colonic lesion identified on abdominal ultrasonography underwent ultrasonographically-guided FNAC using a 21-G needle. The sample was checked immediately by a cytopathologist for adequacy. RESULTS: Eighteen patients had colonic carcinoma; aspiration cytology detected malignant epithelial cells consistent with colonic carcinoma in 17 patients and severely dysplastic cells in one patient. The sensitivity and specificity of ultrasonographically-guided FNAC in the diagnosis of colonic carcinoma was 94 and 100 per cent respectively. The remaining four patients had a diagnosis of ileocaecal tuberculosis, ileocaecal Crohn's disease, and metastatic adenocarcinoma in the liver with no identifiable primary (two patients). One demonstrated granulomata, grew acid-fast bacilli and the patient was treated for tuberculosis. One had inflammatory cells and the patient was found to have Crohn's disease on histology. The remaining two patients had confirmed metastatic adenocarcinoma in the liver on aspiration cytology but suspected colonic lesions were found to be benign on cytological examination and no primary lesion was subsequently demonstrated. There were no complications of FNAC and patients complained of minimal discomfort. There has been no evidence of tumour recurrence with a median follow-up of 12 (range 1-25) months. CONCLUSION: Ultrasonographically-guided FNAC is a valid method for the diagnosis of colonic tumours. 相似文献
96.
97.
Lavine Howard; Huff Joseph W.; Wagner Stephen H.; Sweeney Donna 《Canadian Metallurgical Quarterly》1998,75(2):359
In 3 experiments, the authors assessed whether attitude strength moderates the susceptibility of attitudes to item context effects in surveys. In Experiment 1, respondents completed multiple measures of attitude strength. Three weeks later, respondents participated in a context experiment. Results revealed that respondents with weak attitudes exhibited significantly larger context effect for 1 of 2 issues. In Experiment 2, the results of Experiment 1 were conceptually replicated by use of measures of interattitudinal embeddedness to assess attitude strength. In Experiment 3, significant strength-moderated context effects were found when attitude strength was assessed in a multi-item, multidimensional manner but not when it was assessed with a single item. Discussion focuses on measurement and theoretical issues related to the moderation and mediation of context effects in attitude surveys. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
In the high-performance IC design with increasing design complexity,it is a very important design content to efficiently analyze IC parameters.Thus,the electro-thermal (ET) analyses including power/ground (P/G) analysis and thermal analysis are hot topics in today’s IC research.Since ET analysis equation has a sparse,positive definite and strictly diagonally dominant coefficient-matrix,we prove that the ET analysis has the advantage of locality.Owing to this advantage,localized relaxation method is formally proposed,which has the same accuracy as the global relaxation done with the constraint of the same truncation error limitation.Based on the localized relaxation theory,an efficient and practical localized successive over-relaxation algorithm (LSOR2) is introduced and applied to solve the following three ET analysis problems.(1) Single-node statistical voltage analysis for over-IR-drop nodes in P/G networks;(2) single-node statistical temperature analysis for hot spots in 3D thermal analysis;(3) fast single open-defect analysis for P/G networks.A large amount of experimental data demonstrates that compared with the global successive over-relaxation (SOR) algorithm,LSOR2 can speed up 1-2 orders of magnitudes with the same accuracy in ET analyses. 相似文献
99.
Emma P. Bullock Allison L. Roxburgh Patricia S. Moyer-Packenham Elif Bektas Joseph S. Webster Kathleen A. Bullock 《Journal of Computer Assisted Learning》2021,37(2):557-586
This study focused on an examination of how type, quality and children's awareness of design features in digital math games, along with an awareness of the mathematics goals of the game, were related to learning outcomes. We conducted a parallel conversion mixed methods study with 45 students in Grades 3 and 4 (ages 9–10). Students participated in clinical interviews using three digital math games. The results suggest a moderated mediation relationship in which the quality of the design features moderated the mediating impact of children's awareness of the game's design features, specifically when the child was aware of the mathematics content learning goal (MCLG) of the game. These findings show how important it is that design features are of high quality in a digital math game, and how this is intertwined with children's awareness of the features and the MCLG. When these variables intertwined in just the right way, the interactions between the children and the digital math game afforded mathematical learning growth. 相似文献
100.
Microsystem Technologies - Tuberculosis is a contagious disease caused by the bacteria, Mycobacterium Tuberculosis. Early detection of TB is vital to increase the chances of cure. In this paper, a... 相似文献