ITERATIVE DYNAMIC PROGRAMMING FOR MINIMUM ENERGY CONTROL PROBLEMS WITH TIME DELAY

This paper presents the use of iterative dynamic programming employing exact penalty functions for minimum energy control problems. We show that exact continuously non-differentiable penalty functions are superior to continuously differentiable penalty functions in terms of satisfying final state constraints. We also demonstrate that the choice of an appropriate penalty function factor depends on the relative size of the time delay with respect to the final time and on the expected value of the energy consumption. A quadratic approximation (QA) of the delayed variables is much better than a linear approximation (LA) of the same for relatively large time delays. The QA improves the rate of convergence and avoids the formation of ‘kinks‘. A more general way of selecting appropriate penalty function factors is given and the results obtained using four illustrative examples of varying complexity corroborate the efficacy of the method.     

Fluctuating PEEP (F–PEEP) versus conventional PEEP in dogs with asymmetrical lung injury

Fluctuating PEEP (F-PEEP) is a newly developed PEEP in which end-expiratory pressure (EEP) is periodically changed within a certain range. In a dog model with unilateral lung injury induced by the introduction of hydrochloric acid, F-PEEP in which the EEP was periodically changed from 0.5 to 1.5 kPa at periods of 6 min, and conventional PEEP (C-PEEP) with an optimized EEP of 1.0 kPa, were each applied for 30 min. F-PEEP produced a significantly greater improvement of PaO2 and intrapulmonary shunt (QS/QT) than C-PEEP, and at the low EEP phase, the greatest improvement accompanied by an increased dynamic compliance and a large cardiac output was obtained. These results suggest that F-PEEP provides a useful mode of artificial ventilation for the treatment of unilateral lung injury.     

发音状态下口周软组织移动量的测量

目的引入动态的图象测里概念，进行口周软组织移动量的测量。方洁利用已开发的计算机图象处理系统．对三种测定条件下口腔周围软组织的移动量进行测量研究。结果（1）发／mo／时，口唇突出，上唇的测定点向上内前方．下唇的测定点向下内前方动作，因此．唇上三角形面积变化的大小依次为M3相似文献   

Total anorectal reconstruction with a double dynamic graciloplasty after abdominoperineal reconstruction for low rectal cancer

PURPOSE: Total anorectal reconstruction with a double dynamic graciloplasty was performed after abdominoperineal reconstruction (APR) for low rectal cancer. In four patients an additional pouch was constructed to improve neorectal motility and capacity. The aim of this study was to evaluate the results in the first 20 patients and to report on the preliminary results of patients with an additional pouch. METHODS: Twenty patients with a mean age of 52 (range, 25–71) years and a rectal tumor at a mean of 3 (range, 0–5) cm from the anal verge were treated. In 14 patients the Miles resection, colon pull-through, and construction of a neosphincter were performed in one session. Six patients had the double graciloplasty at an average of 4.1 (range, 1.1–8.8) years after APR. In four patients a pouch was constructed with an isolated segment of distal ileum. RESULTS: After a mean follow-up of 24 (range, 1–60) months after APR, none of the patients developed local recurrence, whereas four patients developed distant metastasis. Fifteen of 20 patients were available for evaluation, and 5 patients were still in training. Of these 15 patients, 8 patients were continent (53 percent), 2 patients were incontinent, and in 5 patients the perineal stoma was converted to an abdominal stoma. Failures were attributable to necrosis of the colon stump (n=2) and incontinence (n=3). At 26 weeks mean resting pressure was 44 (standard deviation (SD), 28) mmHg, and mean pressure during stimulation was 90 (SD, 46) mmHg at a mean of 35 (SD, 1.2) volts at 52 weeks. Mean defecation frequency was three times per day (range, 1–5). Of the eight patients who were continent, six used daily enemas. Mean time to postpone defecation was 11 (range, 0–30) minutes. CONCLUSION: In experienced hands, the double dynamic graciloplasty is an oncologically safe procedure that can have an acceptable functional outcome in a well-selected group of patients. However, to improve the outcome, further modifications will be necessary. So far, the addition of a pouch has not resulted in improved outcome. Supported by the Profileringsfonds of the Maastricht University Hospital, The Netherlands, and by the Stichting Fondsenwervingsactie Volksgezondheid, Amsterdam, The Netherlands. Read in part at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1995.     

小切口动力髋螺钉治疗高龄股骨转子间骨折

[目的]探讨应用小切口动力髋螺钉(DHS)微创固定治疗高龄股骨转子间骨折的方法及临床效果.[方法]回顾性分析2001年8月～2006年1月应用闭合复位、小切口DHS固定治疗37例高龄股骨转子间骨折患者,其中男15例,女22例;年龄72～92岁,平均81.5岁.在C型臂X线机监视下,先将1～2枚克氏针经皮通过大转子打入股骨头上部.另将1枚导针按135°颈干角打入股骨头中央,在导针下做一长约4～5.5 cm纵切口,经导针拧入粗拉力螺纹钉.拔出导针将带套管接骨板沿肌层下插入,并将接骨板的套管套入螺纹钉的尾端.[结果]手术时间40～75 min,平均60 min.术中平均出血55 ml.术后与术前血红蛋白值比较无明显变化.37例均获11～18个月随访,骨折愈合时间10～15周.轻度髋内翻2例,无切口感染、内固定失效及旋转畸形.按董纪元疗效评定标准,优良率94.6%.[结论]小切口DHS微创技术具有手术时间短、出血少、创伤小、并发症少、康复快的特点,是治疗高龄股骨转子间骨折较理想的方法.     

动态心电图对起搏器间歇性感知功能异常的诊断价值

目的 :探讨动态心电图检测对起搏器间歇性感知功能异常的诊断价值。方法 :采用MarquetteMars30 0 0动态心电图仪 ,对 36例 (4 9例次 )安装起搏器的患者进行随访 ,分析起搏、感知及与起搏器相关的心律失常。结果 :共检出起搏器间歇性感知功能异常 17例 (2 4例次 ) ,检出率为 4 7.2 % ,有 5例 (7例次 )合并两项感知异常。所有感知异常除 1例在常规心电图中检出外 ,其余 16例只在动态心电图中发现。检出与起搏器相关的心律失常 12例。根据动态心电图结果进行相应临床处理后 ,部分起搏器的感知功能异常消失。结论 :起搏器的感知功能异常多为间歇性的 ,动态心电图对间歇性感知异常的检出率较高 ,应是起搏器随访不可或缺的手段。     

21 d-6°头低位卧床期间运动训练对动态姿态平衡的影响

目的探讨21 d-6°头低位卧床和卧床运动训练对动态姿态平衡和控制功能的影响. 方法 10名健康男性青年被试者分为卧床对照组和卧床训练组,每组5人,卧床期间训练组每天进行2次、每次30 min逐级增加负荷的头低位功率自行车训练;分别于卧床前和卧床后21 d进行了动态姿态平衡和双膝等速肌力的测试. 结果与卧床前相比,对照组动态本体感觉得分和运动控制适应能力明显降低,双膝相对峰力矩明显降低,同时伴有腘绳肌与股四头肌峰力矩屈/伸比值的明显增加;训练组动态本体感觉得分和运动控制适应能力明显高于对照组,而腘绳肌与股四头肌峰力矩屈/伸比值无明显改变. 结论 21 d-6°头低位卧床运动训练能够明显改善卧床后动态姿态平衡及其动态运动适应功能.     

橡胶活性官能团对增韧环氧树脂动态力学性能的影响

用动态扭摆法测试聚丙烯酸丁酯橡胶增韧环氧树脂的动态力学行为,研究在环氧树脂低固化度和高固化度时,橡胶活性官能团种类(环氧基官能团与羧基官能团)和数量(官能度)对其影响。研究体系中橡胶玻璃化转变温度(Tg)的移动大小,与橡胶和基体树脂健合程度之间的关系。     

A Study on Extension－Flexion Dynamic Lumbar Spine Radiographsin Patients with Lumbar Intervertebral Disc Herniation

ＡＳｔｕｄｙｏｎＥｘｔｅｎｓｉｏｎ－ＦｌｅｘｉｏｎＤｙｎａｍｉｃＬｕｍｂａｒＳｐｉｎｅＲａｄｉｏｇｒａｐｈｓｉｎＰａｔｉｅｎｔｓｗｉｔｈＬｕｍｂａｒＩｎｔｅｒｖｅｒｔｅｂｒａｌＤｉｓｃＨｅｒｎｉａｔｉｏｎＡＳｔｕｄｙｏｎＥｘｔｅｎｓｉｏｎ－Ｆｌｅｘｉ...     

复方桂枝汤中芍药甙煎出量的动态分析

 本实验运用CS－930双波长薄层色谱扫描仪，分析测定桂枝汤方剂在煎煮过程中，其主药芍药的主要化学成分芍药甙量的动态变化。结果表明，煎煮时间在30min时，芍药甙煎出量较高。该法简便、快速，色谱分离良好，排除了其它成分的干扰。平行性和重现性较好。