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Search Results: 1 - 10 of 74959 matches for " 殷建丰 "
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航天器受迫绕飞构型设计与控制
Spacecraft forced fly-around formation design and control

张冉,,韩潮
- , 2017, DOI: 10.13700/j.bh.1001-5965.2016.0768
Abstract: 摘要 针对航天器在轨服务任务对绕飞技术的要求,研究了航天器受迫绕飞构型设计和控制问题。基于C-W (Clohessy-Wiltshire)方程的解析解,提出了双水滴拼接绕飞构型,并将单脉冲或双脉冲受迫绕飞延展至多脉冲绕飞构型设计;推导了伴随航天器初始状态变量与绕飞构型形状参数的关系,得到了4种构型的解析表达式和脉冲控制策略。通过数值仿真算例验证了设计的4种绕飞构型能够实现伴随航天器的慢速绕飞和快速绕飞,比较了不同绕飞构型的燃料消耗和绕飞距离误差。数值结果表明,双水滴拼接绕飞构型总脉冲最小。研究成果完善了航天器受迫绕飞构型设计与控制的相关理论,为工程应用提供参考。
Abstract:In order to meet the requirements of spacecraft fly-around technology in on-orbit service mission, spacecraft forced fly-around formation design and control scheme was investigated. Based on the analytic solution of the C-W(Clohessy-Wiltshire) equations, bi-teardrop formation was proposed. Then multi-impulse fly-around formations were developed after single- or double-impulse formations. The formula between the initial states of following spacecraft and the shape of fly-around formation was derived, and the analytic expressions of four fly-around formations and the impulse control scheme were proposed. Simulation results verify that four designed formations could be used in spacecraft slow fly-around and fast fly-around scenarios. The total fuel consumptions and distance errors of different formations were compared. Numerical results show that bi-teardrop formation has the smallest total impulse. The theory of spacecraft forced fly-around formation design and control is improved, and the results provide reference for engineering application.
航天器悬停构型设计与控制方法
,韩潮,,陈欢
航空学报 , 2015, DOI: 10.7527/S1000-6893.2014.0310
Abstract: 为满足航天器在轨服务任务对悬停技术的需求,对航天器悬停构型的设计与控制问题进行了研究。通过任务航天器轨道设计得出目标航天器与任务航天器的绝对轨道关系,并用以说明悬停轨道的形成机理。结合任务航天器相对于目标航天器的相对轨迹,采用具有严格定义的相对轨道要素,对悬停轨道在目标航天器轨道平面内和平面外的构型进行描述。对"间隔式"的悬停构型脉冲控制策略进行推导,以实现任务航天器在目标航天器任意位置的长期悬停,并在此基础上分析悬停构型变化对速度脉冲的影响。最后,通过典型仿真算例验证所提方法与结果的正确性和有效性,并获得任务航天器在不同悬停轨道间转移的实现过程。研究结果完善了航天器悬停轨道的设计与控制方法,并说明了设计的悬停轨道具有可行性,能够为工程任务设计人员提供参考。
宗教与少数民族人口的婚育

期刊检索-中国人口科学 , 1989,
Abstract: <正>宗教是一种社会历史现象,是人们的社会意识的一种形态。宗教在我国各民族中流传很广,据解放前统计,信仰伊斯兰教的在全国有800多万人,信仰佛教的约有460余万人信仰这两种宗教的人占当时少数民族人口的1/3以上。宗教同少数民族有着密切的联系。古往今来,一种宗教常常被许多不同民族所信仰,反之,一个民族也常常信仰几种不同的宗教。一言以蔽之,信仰宗教的少数民族遍及祖国各地。解放后随着少数民族
苏南社区环境对生育观念转变的影响

人口研究 , 1995,
Abstract: ?苏南人口转变的过程是苏南经济发展、计划生育工作、精神文明等社会综合治理的体现。苏南社区集体经济增加了社区成员的凝聚力,苏南乡镇企业为社区育龄妇女就业、实现自身价值、提高妇女地位创造了机遇。这里从苏南社区环境,社区功能这一角度对苏南生育观念的转变、低生育率环境的形成进行简要论述。
刚性根式基础水平承载性能分析
,龚维民,永高,童小东,
力学与实践 , 2010, DOI: 10.6052/1000-0992-lxysj2008-458
Abstract: 根据Winkler地基梁理论,分析根式基础及根键水平受力特性,并建立计算模型.利用载荷传递法推导根式基础弹性解答,计算其水平向承载性能,获得井身位移、弯矩、剪力和土反力随深度的分布规律.结果表明,根式基础承载性能优于沉井基础,可使顶部水平位移减少35%~45%,承载力提高45%~55%.载荷传递法结果在弹性范围内与试验数据接近,故可用于工程计算.
中西医药物治疗巩膜炎的研究进展
Review on Treatments of Scleritis with Chinese Medicine and Western Medicine
 [PDF]

李超然,
Traditional Chinese Medicine (TCM) , 2015, DOI: 10.12677/TCM.2015.43011
Abstract: 巩膜炎(scleritis),中医称之为“火疳”,为巩膜组织的炎性反应疾病。因巩膜组织由胶原纤维和少量弹性纤维交错致密排列而成,细胞成分和血管较少,导致该疾病并不常见。然而,由于巩膜代谢缓慢,一旦患病,病程往往迁延难愈。在药物治疗上主要有非甾体抗炎药、甾体抗炎药、皮质类固醇药、免疫抑制剂、生物制剂、中药提取物及中药汤剂。本文归纳了上述药物治疗巩膜炎的给药方式及各自临床疗效,分析其中利弊,为临床医疗工作人员提供医疗证据。
Scleritis, also called “episcleritis” in Traditional Chinese Medicine, is an inflammation of sclera tissues. As sclera tissues are compactly composed of collagen fibers and a few of elastic fibers with few cellular constituents and vessels, this disease is uncommon. However, once happened, it has a lingering course due to the slow metabolism of sclera. Drugs mainly include non-steroidal anti-in- flammatory drugs, steroidal anti-inflammatory drugs, corticosteroids, immunosuppressive agent, biological agent, herbal extracts and herbal decoction of Traditional Chinese Medicine. This paper reviewed the administration methods and their clinical effects in treating scleritis with drugs mentioned above, analyzed their advantages and disadvantages, and provided medical evidences for clinical medical staff.
观察清肝利水方对高眼压大鼠眼压及视网膜神经节细胞保护作用
Protective Effects of Qing-Gan-Li-Shui Formula on Intraocular Pressure and Retinal Ganglion Cells of Glaucoma Rats
 [PDF]

王蕾蕾,
Traditional Chinese Medicine (TCM) , 2015, DOI: 10.12677/TCM.2015.42002
Abstract:
目的:青光眼是目前致盲的第二大眼病。清肝利水方是上海名老中医邹菊生先生的经验方,以清肝利水为治则,临床治疗高眼压型青光眼取得明显疗效。本课题探究该方对高眼压大鼠眼压及视网膜神经节细胞的保护作用。方法:采用灼伤巩膜上静脉方法阻断房水回流途径建立高眼压大鼠模型,分别给予清肝利水方、清肝利水方合噻吗心安滴眼液、噻吗心安滴眼液治疗,另设模型组、假手术组。定时监测眼压变化,治疗末分离视网膜,进行H&E染色,神经节细胞计数并观察视网膜形态结构。结果:成功稳定建立高眼压大鼠模型;治疗28天后,中合西药组(9.45 ± 1.04)降眼压效果优于中药组(10.50 ± 1.98),且同时优于西药组(10.91 ± 1.76),且中药参与治疗组降眼压效果和缓稳定。视网膜神经节细胞计数方面,中合西药组(53.00 ± 12.33)高于中药组(47.80 ± 9.60),高于西药组(38.00 ± 12.30)。结论:清肝利水方对高眼压大鼠眼压及视网膜神经节细胞具有保护作用。
Objectives: Glaucoma ranks second among those that induce vision loss. Qing-Gan-Li-Shui Formula is derived from Jusheng Zou, an experienced TCM doctor, and exhibited effective for glaucoma. This project is focusing on related basic research on glaucoma rats’ intraocular pressure (IOP) and retinal ganglion cells (RCGs). Methods: Modeling by occluding episcleral veins. Groups are treated with Qing-Gan-Li-Shui Formula and Timolol Maleate drops, respectively and concurrently. Model group and sham-model group were established as control. We monitored IOP regularly, collected and stained retina with H&E dye to observe RCGs. Results: Model of high IOP was established suc-cessfully. IOP of Chi-Western Group (9.45 ± 1.04) is better than individual significantly (Chinese Medical Group: 10.50 ± 1.98; Western Medical Group: 10.91 ± 1.76). RCGs of Chi-Western Group (53.00 ± 12.33) are more than Chinese Medical Group’s (47.80 ± 9.60) and Western Medical Group’s (38.00 ± 12.30) significantly. Conclusions: Qing-Gan-Li-Shui Formula exhibited protective effects on glaucoma with reduction on IOP and inhibition on RGCs apoptosis.
更换稳定土拌和机工作转子的新型装置

公路交通科技 , 1992,
Abstract: 日前,国内外的路拌稳定上拌和机,大多为一机多用,既可进行稳定土基层的拌和,又可通过更换工作转子铣削旧沥青路面。
复杂型体工件加工切削点误差插值算法研究
Space Error Interpolation Algorithm Research for Complex Shape Workpieces Machining

,李明
- , 2015,
Abstract: 提出了基于形状函数插值方法预测机床工作空间内任一切削点的空间误差方法,对有限元插值法和无网格法插值两种不同方法进行了分析。在比较两种优缺点的基础上,针对复杂型体工件的加工,提出了有限元插值和最小二乘法无网格插值耦合计算方法对机床工作切削点空间误差进行插值预测的方法。仿真和实际切削试验都证明了插值算法的有效性。
A forecasting method for any point space errors in machine tool working region is presented based on the shape function interpolation. Two different methods, finite element method interpolation and meshless method interpolation, have been analyzed. Based on the comparison between the advantages and disadvantages of the above two methods, a space error forecasting method by coupling finite element interpolation and a moving least squares meshless method interpolation for complexity shape was presented
站车禁烟卫生监督检查方法研究
,王国达
中国公共卫生 , 1999,
Abstract: ?依据有关禁烟卫生法规,探讨提出了对站车禁烟单位开展禁烟卫生监督检查的一个可具操作性的技术方法---“站车禁烟卫生监督检查方法”,并验证了此方法的可比性、有效性和可靠性,为铁路或其它相关部门开展禁烟卫生监督检查提供了新方法。
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