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Transplantation of human hepatocytes into tolerized genetically immunocompetent rats 被引量:23
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作者 EdwinC.Ouyang CatherineH.Wu +2 位作者 CherieWalton KittichaiPromrat GeorgeY.Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期324-330,共7页
AIM: To determine whether normal genetically immunocompetent rodent hosts could be manipulated to accept human hepatocyte transplants with long term survival without immunosuppression. METHODS: Tolerance towards human... AIM: To determine whether normal genetically immunocompetent rodent hosts could be manipulated to accept human hepatocyte transplants with long term survival without immunosuppression. METHODS: Tolerance towards human hepatocytes was established by injection of primary human hepatocytes or Huh7 human hepatoma cells into the peritoneal cavities of fetal rats. Corresponding cells were subsequently transplanted into newborn rats via intrasplenic injection within 24h after birth. RESULTS: Mixed lymphocyte assays showed that spleen cells from non-tolerized rats were stimulated to proliferate when exposed to human hepatocytes, while cells from tolerized rats were not. Injections made between 15 d and 17 d of gestation produced optimal tolerization. Transplanted human hepatocytes in rat livers were visualized by immunohistochemical staining of human albumin. By dot blotting of genomic DNA in livers of tolerized rats 16 weeks after hepatocyte transplantation, it was found that approximately 2.5 X 10(5) human hepatocytes survived per rat liver. Human albumin mRNA was detected in rat livers by RT-PCR for 15 wk, and human albumin protein was also detectable in rat serum. CONCLUSION: Tolerization of an immuno-competent rat can permit transplantation, and survival of functional human hepatocytes. 展开更多
关键词 ALBUMINS Animals Cell Line Transformed Disease Models Animal Female Gene Expression Graft Survival Hepatitis HEPATOBLASTOMA Hepatocytes Humans Immune Tolerance IMMUNOCOMPETENCE Liver Liver Neoplasms Lymphocyte Culture Test Mixed Microscopy Confocal Pregnancy RNA Messenger RATS Rats Sprague-Dawley Research Support Non-U.S. Gov't Research Support U.S. Gov't P.H.S.
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Chinese Medicine Improves Postoperative Quality of Life in Endometriosis Patients:A Randomized Controlled Trial 被引量:21
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作者 赵瑞华 刘永 +10 位作者 谈勇 郝增平 孟庆伟 王蕊 龙棣 丁永芬 宋殿荣 徐彩 任志珍 杨艳环 王蔼明 《Chinese Journal of Integrative Medicine》 SCIE CAS 2013年第1期15-21,共7页
Objective: To investigate the effect of Chinese medicine (CM) and Western medicine (WM) on quality of life (QOL) after conservative surgery for endometriosis. Methods: A total of 320 patients with endometdosis... Objective: To investigate the effect of Chinese medicine (CM) and Western medicine (WM) on quality of life (QOL) after conservative surgery for endometriosis. Methods: A total of 320 patients with endometdosis were randomized into two groups by using random block design, CM group (160 cases, activating blood circulation and removing blood stasis treatment based on syndrome differentiation) and WM group (160 cases, gonadotropin-releasing hormone agonist or gestrinone treatment) after conservative surgery. Treatment was given for 3-6 months (according to the revised American Fertility Society scoring system stage), and the Wodd Health Organization QOL-BREF (WHOQOL-BREF) was applied to patients before and after treatment to assess QOL. Results: There were 136 cases in the CM group and 141 cases in the WM group completing therapy. In the CM group, the use of the WHOQOL-BREF showed that the physical, psychological and environmental scores post- treatment were significantly higher than those at pre-treatment (P〈0.05), and for 12 items (pain and discomfort, energy and fatigue, sleep and rest, mobility, activities of daily living, work capacity, negative feelings, health and social care: accessibility and quality, participation in and opportunities for recreation/leisure activities, appetite, QOL score, overall health status and QOL), the difference in scores was significant (P〈0.05). In the WM group, 4 items (pain and discomfort, opportunities for acquiring new information and skills, QOI_ score, overall health status and QOL) had significantly different scores post-treatment compared with those at pre-treatment (P〈0.05). Before treatment, the QOL in the two groups of patients showed no significant difference (P〉0.05). After treatment, the scores for physical health in the CM group were significantly higher than those of the WM group (P〈0.05) and the scores of 4 items (mobility, activities of daily living, sexual activity, QOL score) in the CM 展开更多
关键词 ENDOMETRIOSIS quality of life Chinese medicine gonadotropin-releasing hormone agonist WorldHealth Organization QOL-BREF
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倾向得分法综述 被引量:15
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作者 Alex Z Fu 唐艳 陈刚 《中国药物经济学》 2008年第2期27-34,共8页
倾向得分是在给定观察变量前提下接受干预的条件概率。倾向得分法试图通过准随机过程来去除比较组与其他观察因素的混杂效应。本文首先把倾向得分法与随机选择及标准匹配技术进行了比较。然后描述了倾向得分法的实际应用。第一阶段是建... 倾向得分是在给定观察变量前提下接受干预的条件概率。倾向得分法试图通过准随机过程来去除比较组与其他观察因素的混杂效应。本文首先把倾向得分法与随机选择及标准匹配技术进行了比较。然后描述了倾向得分法的实际应用。第一阶段是建立倾向得分模型,第二阶段就应用倾向得分去评价研究结果。最后本文对倾向得分的优劣势进行了讨论。 展开更多
关键词 协变量 干预效果 分法 倾向 得分 回归模型 条件概率 对照组 配对 因果效应
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基于LabVIEW的苹果擦伤分级系统设计 被引量:9
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作者 高晓阳 Paul H Heinemann Joseph Irudayaraj 《农业机械学报》 EI CAS CSCD 北大核心 2006年第4期152-154,共3页
基于美国USDA苹果分级标准研制了苹果擦伤检测分级系统样机。系统依据所研究的苹果表面擦伤拉曼光谱PLS/CVA处理和UNEQ模型分类,通过设计的LabVIEW虚拟仪器控制系统实时完成苹果分级。对48个预先分级的美国红元帅苹果(reddelicious#4167... 基于美国USDA苹果分级标准研制了苹果擦伤检测分级系统样机。系统依据所研究的苹果表面擦伤拉曼光谱PLS/CVA处理和UNEQ模型分类,通过设计的LabVIEW虚拟仪器控制系统实时完成苹果分级。对48个预先分级的美国红元帅苹果(reddelicious#4167)分别进行两轮实际分级实验来评估该系统的性能。实验结果表明该分级检测系统对无擦伤、轻擦伤和重擦伤苹果组的分级平均准确率分别为100%、99%、97%。分级系统每分钟可分级苹果3~6个,对运动苹果分级误判率较低,是实施苹果自动检测分级生产线的基本模块。 展开更多
关键词 苹果 分级系统 擦伤 拉曼光谱 虚拟仪器
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Bi-normalized response spectral characteristics of the 1999 Chi-Chi earthquake 被引量:8
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作者 徐龙军 谢礼立 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2004年第2期147-155,共9页
To develop uniform and seismic environment-dependent design spectrum,common acceleration response spectral characteristics need to be identified.In this paper,a bi-normalized response spectrum (BNRS) is proposed,which... To develop uniform and seismic environment-dependent design spectrum,common acceleration response spectral characteristics need to be identified.In this paper,a bi-normalized response spectrum (BNRS) is proposed,which is defined as a spectrum of peak response acceleration normalized with respect to peak acceleration of the excitation plotted vs.the natural period of the system normalized with respect to the spectrum predominant period,Tp.Based on a statistical analysis of records from the 1999 Chi-Chi earthquake,the conventionally normalized response spectrum(NRS) and the BNRS are examined to account for the effects of soil conditions,epicentral distance,hanging wall and damping.It is found that compared to the NRS the BNRS is much less dependent on these factors.Finally,some simple relationships between the BNRS for a specified damping ratio and that for a damping ratio of 5%,and between the spectra predominant period and epicentral distance for different soil types are provided. 展开更多
关键词 earthquake design spectra normalized response spectrum bi-normalized response spectrum spectral predominant period Chi-Chi earthquake
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废碱液工业化处理技术评价 被引量:10
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作者 SABAH A.KURUKCHI 吕玉臣 《广东化工》 CAS 1997年第5期66-68,共3页
对炼油厂/石油化工生产厂而言,恰当处理工业废物是件又使人头痛又费钱的问题。本文将对废碱液处理目前可采用的工业化技术进行探讨。并就各种废碱液处理工艺进行比较,对各自的优、缺点做简要评价。 乙烯厂中的裂解气所含的酸性气体主要... 对炼油厂/石油化工生产厂而言,恰当处理工业废物是件又使人头痛又费钱的问题。本文将对废碱液处理目前可采用的工业化技术进行探讨。并就各种废碱液处理工艺进行比较,对各自的优、缺点做简要评价。 乙烯厂中的裂解气所含的酸性气体主要是H_2S和CO_2及少量的RSH、HCN等。这些酸性气体在压缩系统两个相邻压缩段之间的吸收塔中通过与稀释的氢氧化钠反应来除掉。 展开更多
关键词 废水处理 工业化处理 废碱液
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阴离子添加剂在围产前期奶牛饲料中的应用 被引量:8
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作者 刘庆平 《中国奶牛》 北大核心 2004年第4期23-26,共4页
关键词 阴离子添加剂 围产前期 奶牛饲料 免疫功能
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Impact of China-ASEAN Free Trade Area on China's International Agricultural Trade and Its Regional Development 被引量:8
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作者 Huanguang Qiu Yang Jun +1 位作者 Jikun Huang Ruijian Chen 《China & World Economy》 SCIE 2007年第5期77-90,共14页
This study aims to examine the impact of the China-ASEAN Free Trade Area (CAFTA) on China's international agricultural trade and its regional agricultural development, using the Global Trade Analysis Project model ... This study aims to examine the impact of the China-ASEAN Free Trade Area (CAFTA) on China's international agricultural trade and its regional agricultural development, using the Global Trade Analysis Project model and the China Agricultural Decision Support System. Our analysis showed that: (i) CAFTA will improve resource allocation efficiencies for both China and ASEAN and will promote bilateral agricultural trade and, hence, will have positive effects on the economic development of both sides; (ii) CAFTA will accelerate China's export of the agricultural commodities in which it has comparative advantages, such as vegetables, wheat and horticultural products, but at the same time bring about a large increase in imports of commodities such as vegetable oil and sugar; and (iii) CAFTA will have significantly varying impacts on China's regional agricultural development because of large differences in the agricultural production structure in each region. Our results indicate that agriculture in the northern, northeastern and eastern regions of China will benefit from CAFTA, whereas agriculture development in southern China will suffer. Those regional specific impacts are quite different from the effects brought by multilateral free trade treaties, such as those of the WTO, which usually have positive effects on south China but negative impacts on the northern and western parts of China. 展开更多
关键词 free trade area agricultural trade regional development model analysis
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An operational modal analysis method in frequency and spatial domain 被引量:9
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作者 王彤 张令弥 田村幸雄 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2005年第2期295-300,共6页
A frequency and spatial domain decomposition method (FSDD) for operational modal analysis (OMA) is presented in this paper, which is an extension of the complex mode indicator function (CMIF) method for experime... A frequency and spatial domain decomposition method (FSDD) for operational modal analysis (OMA) is presented in this paper, which is an extension of the complex mode indicator function (CMIF) method for experimental modal analysis (EMA). The theoretical background of the FSDD method is clarified, Singular value decomposition is adopted to separate the signal space from the noise space. Finally, an enhanced power spectrum density (PSD) is proposed to obtain more accurate modal parameters by curve fitting in the frequency domain. Moreover, a simulation case and an application case are used to validate this method. 展开更多
关键词 operational modal analysis modal parameters identification frequency and spatial domain
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美国处理医疗损伤责任纠纷的法律程序 被引量:5
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作者 刘涓 王朝曦 宋文质 《中国医院》 2006年第11期5-9,共5页
不论是一般的民事或刑事案件,还是医疗损伤责任案件,法律的具体实施程序实际上都是一个个独立的决策过程。本文介绍了美国医疗损伤责任纠纷的法庭外解决方式、医疗损伤责任纠纷的法庭诉讼程序和其他与医疗损伤责任纠纷相关的法律。
关键词 医疗损伤 医疗纠纷 法律
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Antiplane response of isosceles triangular hill to incident SH waves 被引量:8
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作者 邱发强 刘殿魁 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2005年第1期37-46,共10页
In this paper, antiplane response of an isosceles triangular hill to incident SH waves is studied based on the method of complex function and by using moving coordinate system. The standing wave function, which can sa... In this paper, antiplane response of an isosceles triangular hill to incident SH waves is studied based on the method of complex function and by using moving coordinate system. The standing wave function, which can satisfy the governing equation and boundary condition, is provided. Furthermore, numerical examples are presented; the influences of wave number and angle of the incident waves and the angle of the hill’s peak on ground motion are discussed. 展开更多
关键词 Boundary conditions Function evaluation Mathematical models Problem solving SCATTERING STIFFNESS Stresses Surfaces Complex functions Isosceles triangular hill Moving coordinate system Scattering of SH WAVES
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Does Education Still Pay Off in Rural China:Revisit the Impact of Education on Off-farm Employment and Wages 被引量:8
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作者 Haiqing Zhang Linxiu Zhang +1 位作者 Renfu Luo Qiang Li 《China & World Economy》 SCIE 2008年第2期50-65,共16页
The present study considers how education affects off-farm job participation and wages. We use a nationally representative dataset from a survey conducted in 5 provinces, 101 villages and 808 households by the authors... The present study considers how education affects off-farm job participation and wages. We use a nationally representative dataset from a survey conducted in 5 provinces, 101 villages and 808 households by the authors in early 2005. The empirical results show that educational attainment, skill training and years of experience of rural residents have positive, statistically significant effects on off-farm employment. The average return to a year of education is 7percent, which is higher than those observed in previous studies. We also find the return to an additional year of schooling to be higher for post-junior high schooling than for junior high and below schooling: 11.8 versus 3.2 percent. We conclude that not only does education still pays off in rural China, but also the rate of return to education is increasing over time. 展开更多
关键词 off-farm employment retums to education rural labor force
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从“为大众的住宅”到“为大众的社区” 从“居住区规划”到“社区建设” 被引量:4
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作者 张庭伟 《时代建筑》 2004年第5期30-33,共4页
在历经20年的建设后,中国的城市住房在数量和质量方面都有了飞跃发展,但同时,城市的富裕居民和贫困居民在住房条件上的鸿沟也日益加大。有鉴于美国在住房建设方面的经验,文章提出应制定一种侧重于社会发展的住房新政策,并提出“为大众... 在历经20年的建设后,中国的城市住房在数量和质量方面都有了飞跃发展,但同时,城市的富裕居民和贫困居民在住房条件上的鸿沟也日益加大。有鉴于美国在住房建设方面的经验,文章提出应制定一种侧重于社会发展的住房新政策,并提出“为大众的社区”和“社区建设”的概念。 展开更多
关键词 住房政策 大众承受力 住区建设
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How Has Rural Tax Reform Affected Farmers and Local Governance in China? 被引量:7
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作者 Ran Tao Ping Qin 《China & World Economy》 SCIE 2007年第3期19-32,共14页
Using nationally representative data, the present paper examines the impact of China's ongoing rural tax reform on farmers. The difficulties in further local governance restructuring are also discussed. It is argued ... Using nationally representative data, the present paper examines the impact of China's ongoing rural tax reform on farmers. The difficulties in further local governance restructuring are also discussed. It is argued that the issues associated with rural taxation and local governance in China result from inherent tension between an increasingly liberalized economic system and a still centralized political system. Although rural tax reform has helped to reduce farmers" tax burdens in the short term, the establishment of an effective local governance regime requires coordinated reforms to downsize local bureaucracy by providing social security for laid-off cadres, to strengthen local accountability by granting higher local formal tax autonomy, and to promote meaningful participation by expanding local democracy. 展开更多
关键词 farmers' tax burdens local governance rural tax reform tax incidence
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The effect of Shen-Fu on gastrointestinal tract injury and its potential mechanism during cardio-pulmonary bypass in patients undergoing cardiac surgery 被引量:7
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作者 夏中元 詹丽英 +1 位作者 何宇红 刘先义 《Chinese Journal of Traumatology》 CAS 2003年第4期245-248,共4页
Objective: To investigate the effect of Shen-Fu (SF) injection on gastrointestinal tract injury and its potential mechanism.Methods: Thirty-eight patients undergoing elective open heart surgery were assigned to Group ... Objective: To investigate the effect of Shen-Fu (SF) injection on gastrointestinal tract injury and its potential mechanism.Methods: Thirty-eight patients undergoing elective open heart surgery were assigned to Group C (control group, n = 18) and Group SF (n = 20) randomly. In Group SF, the patients received intravenous injection of SF (0.5 ml/kg) at the beginning of the surgery followed by a continuous infusion of 100 ml SF (1.0 ml/kg) solution diluted by saline at a rate of 0.004 ml · Kg-1 · min-1 with a Grasby pump. The control group was injected with normal saline in the same volume. Gastric intramucosal pH (pHi), activity of blood diamine oxidase ( DAO ), and concentrations of blood LPS and IL-6 were measured before CPB ( S0) and 1 h ( S1 ) and 2 h ( S2) after aortic declamping, respectively.Results: In Group C, pHi value was significantly lower at S1 and S2 than at S0 ( mean P <0.01) and blood DAO and concentrations of LPS and IL-6 were significantly higher at S1 and S2 than at S0 ( meanP < 0.01). In Group SF, pHi was obviously lower at S1 and S2 than at S0(P< 0.05) but LPS and IL-6 levels and DAO were higher at S, (mean P<0.05). Blood DAO and LPS level demonstrated significant negative correlations with pHi ( mean P < 0.01) while LPS concentration showed a positive correlation with blood DAO (P < 0.01) and IL-6 concentration (P < 0.05). At S1 and S2 after aortic declamping, the levels of pHi were higher in Group SF than in Group C (mean P <0.01 ) but DAO and LPS and IL-6 levels were significantly lower in Group SF than in Group C ( P <0.01).Conclusions: SF has a protective effect on gastrointestinal tract and can reduce inflammatory actions. 展开更多
关键词 Gastrointestinal tract Wounds and injuries Cardiopulmonary bypass Shen-Fu injection
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A comparative study of semi-active control strategies for base isolated buildings 被引量:4
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作者 Oliveira F. Morais P. Suleman A. 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2015年第3期487-502,共16页
A comparative analytical study of several control strategies for semi-active(SA) devices installed in baseisolated buildings aiming to reduce earthquake induced vibrations is presented.Three force tracking schemes com... A comparative analytical study of several control strategies for semi-active(SA) devices installed in baseisolated buildings aiming to reduce earthquake induced vibrations is presented.Three force tracking schemes comprising a linear controller plus a 'clipped' algorithm and a nonlinear output feedback controller(NOFC) are considered to tackle this problem.Linear controllers include the integral controller(I),the linear quadratic regulator(LQR) and the model predictive controller(MPC).A single degree-of-freedom system subjected to input accelerograms representative of the Portuguese seismic actions are first used to validate and evaluate the feasibility of these strategies.The obtained results show that structural systems using SA devices can in general outperform those equipped with passive devices for lower fundamental frequency structural systems,namely base-isolated buildings.The effectiveness of the proposed strategies is also evaluated on a 10 storey base-isolated dual frame-wall building.The force tracking scheme with an integral controller outperforms the other three as well as the original structure and the structure equipped with passive devices. 展开更多
关键词 semi-active control integral controller linear qua
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Operation characteristics of AMS-02 loop heat pipe with bypass valve 被引量:6
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作者 WANG NaiHua Joseph BURGER +6 位作者 LUO Feng CUI Zheng XIN GongMin DU WenJing SONG JiWei CHEN Yan CHENG Lin 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第7期1813-1819,共7页
Loop heat pipes (LHPs) were designed for the alpha magnetic spectrometer (AMS-02) to dissipate heat from the cryocoolers. A bypass valve is applied to the LHP to keep the cryocooler temperature above its limit (... Loop heat pipes (LHPs) were designed for the alpha magnetic spectrometer (AMS-02) to dissipate heat from the cryocoolers. A bypass valve is applied to the LHP to keep the cryocooler temperature above its limit (-20℃) in cold environment. Extensive experiments were performed on operation characteristics of LHPs with the bypass valve for AMS-02 during thermal vacuum and thermal balance (TVTB) test. We found that the bypass valve can start up successfully in cold environment. With the bypass valve, the evaporator temperature is stable and can meet the requirement of the cryocooler. We analyzed three operating modes of the bypass valve. Set point temperature and regulation temperature shifts were observed and their relations with the bypass valve temperature were given. 展开更多
关键词 alpha magnetic spectrometer loop heat pipe bypass valve operation characteristic
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Characteristics of Micrometeorology in the Surface Layer in the Tibetan Plateau 被引量:5
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作者 刘辉志 张宏升 +5 位作者 卞林根 陈家宜 周明煜 徐祥德 李诗明 赵翼浚 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第1期73-88,共16页
The data of the meteorological elements in the surface layer have been analyzed which were obtained during the IOP of TIPEX from May to July 1998 inG&#283;rz&#283;, Damxung and Qamdo. The characteristics of th... The data of the meteorological elements in the surface layer have been analyzed which were obtained during the IOP of TIPEX from May to July 1998 inG&#283;rz&#283;, Damxung and Qamdo. The characteristics of the diurnal variations and the vertical profiles of the wind velocity, temperature and humidity in the surface layer have been investigated. Some interesting results have been obtained. The moisture inversion phenomena occured during the daytime in the surface layer have also been discussed. 展开更多
关键词 Diurnal variation of meteorological element Vertical profile Tibetan Plateau
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A technique to improve the empirical mode decomposition in the Hilbert-Huang transform 被引量:5
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作者 陈扬波 冯青 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2003年第1期75-86,共12页
The Hilbert-based time-frequency analysis has promising capacity to reveal the time-variant behaviors of a sys- tem.To admit well-behaved Hilbert transforms,component decomposition of signals must be performed beforeh... The Hilbert-based time-frequency analysis has promising capacity to reveal the time-variant behaviors of a sys- tem.To admit well-behaved Hilbert transforms,component decomposition of signals must be performed beforehand.This was first systematically implemented by the empirical mode decomposition(EMD)in the Hilbert-Huang transform,which can provide a time-frequency representation of the signals.The EMD,however,has limitations in distinguishing different components in narrowband signals commonly found in free-decay vibration signals.In this study,a technique for decompo- sing components in narrowband signals based on waves' beating phenomena is proposed to improve the EMD,in which the time scale structure of the signal is unveiled by the Hilbert transform as a result of wave beating,the order of component ex- traction is reversed from that in the EMD and the end effect is confined.The proposed technique is verified by performing the component decomposition of a simulated signal and a free decay signal actually measured in an instrumented bridge structure.In addition,the adaptability of the technique to time-variant dynamic systems is demonstrated with a simulated time-variant MDOF system. 展开更多
关键词 time-frequency analysis Hilbert-Huang transform component decomposition
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Strategic Thinking of the Internet of Things and M2M Services 被引量:6
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作者 Qi Qingzhong 《ZTE Communications》 2010年第1期4-7,共4页
Editor's Desk:The Internet of Things is an important part of the emerging high-tech industry and has been recognized as one of the important technologies for addressing global financial crisis and revitalizing the e... Editor's Desk:The Internet of Things is an important part of the emerging high-tech industry and has been recognized as one of the important technologies for addressing global financial crisis and revitalizing the economy. Therefore, at the beginning of the new year, we are honored to have invited Mr. Samuel Qi (Qi Qingzhong), a famous Chinese communication technology expert and GM of Shanghai Symphony Telecommunications Co., Ltd., to give his views on the development strategy of the Internet of Things and Machine to Machine (M2M) Communications. 展开更多
关键词 In Strategic Thinking of the Internet of Things and M2M Services
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