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Micro-Electro-Mechanical-Sensor Inertial Navigation System-Assisted Global Navigation Satellite System Receiver Acquisition Scheme and Performance Evaluation

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Journal of Shanghai Jiaotong university(Science) 2011年第6期16卷 728-733页

作者：叶萍战兴群张炎华 School of Aeronautics and Astronautics Shanghai Jiaotong University

When an aircraft moves under a low carrier-to-noise ratio （CNR） or at a high speed, increasing the sensitivity of global navigation satellite system （GNSS） receiver is a goal quite hard to achieve. A novel acquisition scheme assisted with micro-electro-mechanical-sensor （MEMS） inertial navigation system （INS） is presented to estimate the Doppler caused by user dynamics relative to each satellite ahead of time. Based on tightly coupled GNSS/INS estimation algorithm, MEMS INS Doppler error that can be achieved is first described. Then, by analyzing the mean acquisition time and signal detection probability, the MEMS INS-assisted acquisition capabilities in cold, warm and hot starts are quantitatively determined and compared with the standard GNSS acquisition capability. The simulations and comparisons have shown that： the acquisition time in cold start can be shortened by at least 23 s, the time in warm start can be shortened to i s and the acquisition capability is improved 95%, and the reaequisition time in hot start can be shortened by around 0.090 s and the capability can be enhanced 40%. The results demonstrate the validity of the novel method.

关键词： global navigation satellite system (GNSS) micro-electro-mechanical-sensor (MEMS) inertial navigation system (INS) cold start warm start hot start

Virtual reality simulator for training urologists on transurethral prostatectomy

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Chinese Medical Journal 2013年第7期126卷 1220-1223页

作者： ZHU He ZHANG Yi LIU Jin-shun WANG Gang YU Cheng-fan NA yan-qun Wu Jieping Urology Center Shougang Hospital Peking University Beijing 100144 China

Background A virtual reality simulator provides a novel training model for improving surgical skills in a variety of fields. They can simulate a variety of surgical scenarios to improve the overall skills required for endoscopic operations, and also record the operative process of trainees in real-time and allow for objective evaluation. At present, some simulators for transurethral resection of the prostate （TURP） are available. The utility of virtual reality simulators in training of transurethral prostatectomy was investigated. Methods Thirty-eight urologists were randomly selected to take part in a simulation based training of TURP using the TURPSimTM system. Pre and post-training global rate scale （GRS） scores and objective parameters recorded by the simulator were assessed. Then, questionnaires were filled out. Results Compared with baseline levels, the GRS scores of trainees increased （18.0±4.0 vs. 12.4±4.2, P 〈0.001）, while the rate of capsule resection （26.3%±0.6% vs. 21.2%±0.4%, P 〈0.001）, amount of blood loss （（125.8±86.3） ml vs. （83.7±41.6） ml, P 〈0.001）, external sphincter injury （3.6±2.9 vs. 2.0±2.0, P 〈0.001 ） decreased significantly after training. Most trainees were satisfied with the simulator based training and believed that the simulator accurately mimicked actual surgical procedures and could help improve their surgical skills. Conclusions As a new method of training on transurethral prostatectomy skills, training of TURP using a virtual simulator can help urologists improve their surgical skills and safety. Therefore, the application of the TURPSimTM system in education and training of urologic surgery is warranted.

关键词： prostate transurethral prostatectomy computer simulation continuing medical education surgical skill training

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发动机薄壁盘类零件振动疲劳试验技术研究

应用力学学报 2020年第5期37卷 1993-1998,I0011页

作者：慕琴琴由于燕群中国飞机强度研究所西安710065

以某发动机薄壁盘类零件为例,采用分析与试验相结合的方法进行了薄壁盘类零件振动疲劳试验方案设计与调试,验证了分析与试验方法的可靠性。并在此基础上,采用共振驻留控制方式进行了振动疲劳正式试验,获取了振动疲劳试验过程中的相关物... 详细信息

以某发动机薄壁盘类零件为例,采用分析与试验相结合的方法进行了薄壁盘类零件振动疲劳试验方案设计与调试,验证了分析与试验方法的可靠性。并在此基础上,采用共振驻留控制方式进行了振动疲劳正式试验,获取了振动疲劳试验过程中的相关物理参数的变化规律,包括共振频率和等效应力与激振加速度量值及循环数之间的关系,并且验证了高温合金材料在高周振动疲劳服役中的材料硬化等性能,最后得到了该薄壁零件的疲劳寿命。所提出的试验设计方法、试验方法及得出的结论可为发动机薄壁盘类零件振动疲劳性能考核验证及强度性能评估提供一定的参考。

关键词：薄壁盘类零件振动疲劳试验共振驻留控制方法疲劳寿命高温合金

Nutritive composition of Chinese oak silkworm,Antheraea pernyi,a traditional edible insect in China:a review

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Nutritive composition of Chinese oak silkworm,Antheraea pern...

Theoretical Studies on the Actinide Borospherenes

中国蚕学会2021年学术年会

作者： qun Li Yu-Ping Li D.Ambühl yan-qun Liu Mu-Wang Li Li Qin Department of Sericulture College of Bioscience and BiotechnologyShenyang Agricultural University Institute for Environment and Natural Resources ZHAW Zurich University of Applied Sciences Key Laboratory of Silkworm and Mulberry Genetic Improvement Ministry of Agriculture and Rural AffairsSericultural Reaearch InstituteChinese Academy of Agricultural Sciences

Edible insects are considered rich in protein and a variety of micronutrients and are therefore regarded as one of the potential contributors to food *** Chinese oak silkworm,Antheraea pernyi（Guérin-Méneville 1855）,has been collecting from oak trees in the wild for at least 2000 years,and Chinese farmers developed the artificial rearing of Chinese oak silkworm for silk production before the 17th ***,about 5×104 t of *** including the fifth-instar larvae,pupae and moths are consuming as delicious food in China per year.A total of 18 amino acids,16 fatty acids,13 minerals,five vitamins and seven human hormones in the human diet have been detected in larvae,pupae and adults of *** this review,we summarised the complete nutrient content of four developmental stages of this economically important *** available data suggest that Chinese oak silkworm is a nutrition-rich and healthy and sustainable food item of the *** review could provide podium to food and feed industry for framing a strategy for molecular nutritional component intake into the diets of humans and ***,this paper would contribute to advance exploring for developmental and metabolic biology of Chinese oak silkworm.

关键词： Amino acids Fatty acids Minerals Vitamins Hormones

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Theoretical Studies on the Actinide Borospherenes

中国化学会第八届全国物理无机化学学术会议

作者： Cong-Zhi Wang Tao Bo Jian-Hui Lan qun-yan Wu Zhi-Fang Chai Wei-qun Shi Institute of High Energy Physics Chinese Academy of Sciences

Since the recent observation of the first all-boron fullerenes(D B) in 2014, metal-doped borospherenes have been received extensive attention. So far, in spite of theoretical efforts on metalloborospherenes, the feasi...

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基于线性模型的自适应信赖域方法

运筹与管理 2016年第4期25卷 87-92页

作者：周群艳江苏理工学院数理学院江苏常州213001

为求解大规模无约束优化问题,本文提出了一种自适应线性信赖域法。与传统的线性信赖域法相比,新方法借助一数量矩阵近似Hesse阵,并据此计算线性信赖域半径。理论上证明了新算法的全局收敛性,数值实验表明新算法非常适合大规模问题的求解。

关键词：无约束优化信赖域方法线性模型数值实验

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中介语中程度副词的使用情况分析

汉语学习 2006年第6期 66-72页

作者：郑艳群北京语言大学对外汉语研究中心

本文对汉语中介语语料库中程度副词的使用情况进行了考察,得出以下结论:以往文献中的偏误类型在本语料库中都出现了,但是以往文献中从经验出发归纳出的某些偏误类型在语料库中用例并不多,而实际语料中存在的某些偏误却在已有的研究结果... 详细信息

本文对汉语中介语语料库中程度副词的使用情况进行了考察,得出以下结论:以往文献中的偏误类型在本语料库中都出现了,但是以往文献中从经验出发归纳出的某些偏误类型在语料库中用例并不多,而实际语料中存在的某些偏误却在已有的研究结果中很难找到相应的解释。本研究有利于探讨副词教学策略,促进面向对外汉语教学的本体研究。

关键词：中介语语料库程度副词考察分析

我国房地产投资是否具有挤出效应?——基于I(2)VECM的分析

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数理统计与管理 2016年第2期35卷 329-340页

作者：张延群中国社会科学院数量经济与技术经济研究所北京100732

本文实证检验我国房地产与非房地产投资之间的关系,通过构建两者资本存量之间的二阶单整(I(2))向量自回归(VAR)模型,两者投资额之间的一阶单整(I(1))VAR模型,以及投资增长速度之间的平稳(I(0))VAR模型,运用协整分析技术,将两者之间的关... 详细信息

本文实证检验我国房地产与非房地产投资之间的关系,通过构建两者资本存量之间的二阶单整(I(2))向量自回归(VAR)模型,两者投资额之间的一阶单整(I(1))VAR模型,以及投资增长速度之间的平稳(I(0))VAR模型,运用协整分析技术,将两者之间的关系分为长期、中期、短期并进行了实证检验。本文还对房地产投资的挤出效应进行了检验。长期来看,房地产投资对非房地产投资具有明显的挤出效应,而非房地产投资能够促进房地产投资的增长。

关键词：房地产投资挤出效应协整关系 I(2)VECM模型

从“中国学派”到“中国电影学派”:中国电影学派的体系建构

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湖南科技大学学报（社会科学版） 2022年第4期25卷 118-127页

作者：李燕群华中师范大学文学院湖北武汉430079

“中国电影学派”的研究热潮基于建构国家电影品牌的战略设想,它曾受到文艺研究“中国学派”的启发,“中国动画学派”和“中国电影理论批评学派”则从创作实践和理论建构两个层面推动了其建构进程。学界目前主要从三个层面建构“中国电... 详细信息

“中国电影学派”的研究热潮基于建构国家电影品牌的战略设想,它曾受到文艺研究“中国学派”的启发,“中国动画学派”和“中国电影理论批评学派”则从创作实践和理论建构两个层面推动了其建构进程。学界目前主要从三个层面建构“中国电影学派”:概念内涵界定(核心);理论体系建构(关键);创作体系、学术共同体和教育体系的建构(基础与保障)。未来,学界还需开拓新思路,在学术史视域下拓宽“中国电影学派”的研究路径与范畴。

关键词：中国电影学派中国学派观念体系建构学术理路