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61.
62.
Huang Yuying Zhong Weifang Qin Qinghua 《Computer Methods in Applied Mechanics and Engineering》1992,100(3):315-323
The postbuckling behavior of plates on an elastic foundation is studied by using the boundary element method (BEM). A new fundamental solution of lateral deflection is derived through the resolution theory of a differential operator, and a set of boundary element formulae in incremental form is presented. By using these formulae, the BEM solution procedure becomes relatively simple. The results of a number of numerical examples are compared with existing solutions and good agreement is observed. It shows that the proposed method is effective for solving the postbuckling problems of plates with arbitrary shape and various boundary conditions. 相似文献
63.
Zheng Jiao Minghong Wu Jianzhong Gu Zheng Qin 《IEEE sensors journal》2003,3(4):435-438
Zinc ferrite is a promising sensor material. In this paper, thin films of nanocrystalline zinc ferrite were deposited on alumina substrates by nebulization of a 0.01-M solution of a mixture of ZnCl/sub 2/ and FeCl/sub 3/ in ethanol (Zn:Fe=1:2) followed by pyrolysis and annealing in flowing air. The resulting films were characterized by X-ray diffraction and scanning electron microscopy, and the gas-sensing properties of as-deposited films were also investigated. 相似文献
64.
农村电网的无功功率补偿 总被引:1,自引:0,他引:1
张晓琴 《重庆科技学院学报(社会科学版)》2002,17(3):35-37
阐述农村电网无功补偿的意义 .针对农村电网和农村用户的特点 ,提出在农网改造中 ,对各级电力线路 ,以提高农村电网的功率因数 ,保证农网安全、可靠和经济运行 .和电力用户进行无功补偿的方法 相似文献
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Recent evidence indicates few differences between patients recruited through advertising and by consultation referral, and there is some suggestion that those recruited through advertising are more representative of the target community population. However little has been reported on differences in placebo response and compliance in these two patient groups. We conducted a retrospective chart review of 49 patients with major depressive disorder (MDD), recruited through advertising or consultation, randomized to placebo in five clinical trials. Variables included demographics, clinical history, efficacy, compliance, and completion data. Homogeneity was demonstrated for most variables. Differences in placebo groups included significantly lower Hamilton Rating Scale for Depression (HAM-D) scores for the advertisement group throughout the trials. Advertisement patients were also more likely to be early placebo responders and in remission at Days 14 and 28. No differences were found in completion rates or reasons for early termination. Compliance was excellent for both groups. Early placebo response of the advertisement group reinforces the need for trials of at least 8 weeks. In addition, consultation patients may have a more severe illness and be treatment resistant, suggesting they are less generalizable to community practice populations. 相似文献
67.
Y Sun A Hildesheim LA Brinton PC Nasca CL Trimble RJ Kurman RP Viscidi KV Shah 《Canadian Metallurgical Quarterly》1996,63(2):200-203
We describe a case of positional dyspnea due to compression of the tracheobronchial tree by an extensive thoracic aneurysm. In a 77-year-old woman with long-standing systemic hypertension, intermittent anterior chest pain gradually developed over several years. She had no history of asthma or thoracic trauma. She was admitted to our hospital because of sudden, severe shortness of breath. The breathlessness was markedly worse when she lay on her back or on her right side. On physical examination, she was in acute respiratory distress with cyanosis, severe hypertension (180/110 mmHg), tachycardia, and inspiratory stridor. A chest X-ray film showed loss of volume and nearly complete radiopacity of the left hemithorax. Arterial blood gas analysis revealed an arterial oxygen partial pressure of 54.8 mmHg, a carbon dioxide partial pressure of 39.8 mmHg, and an oxygen saturation of 84.5 percent on room air. Computed tomographic examination of the thorax showed dilation of the aortic arch and descending aorta, and marked compression of the trachea and the left main bronchus. Examination with a fiberoptic bronchoscope revealed extrinsic compression of the trachea just proximal to the carina. The patient's symptoms stabilized. However, she did not undergo surgery because of her age and because of the size of the aneurysm. She died due to rupture of the aneurysm. 相似文献
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一个表示和运用非功能性需求的框架 总被引:1,自引:0,他引:1
本文分析了一个软件开发进程中表示和运用非功能性需求的综合框架,该框架的目的是开发一套技术以调整软件开发进程中的设计决策,从而强调了依据非功能需求,探索合理化的软件开发进程。 相似文献