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A digital open-loop Doppler processing prototype for deep-space navigation

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Science China(Physics,Mechanics & Astronomy) 2009年第12期52卷 1849-1857页

作者： JIAN NianChuan SHANG Kun ZHANG SuJun WANG MingYuan SHI Xian PING JingSong YAN JianGuo TANG GeShi LIU JunZe QIU Shi fung lai-Wo ZHANG Hua WANG Zhen GOU Wei Shanghai Astronomical Observatory of Chinese Academy of Sciences Shanghai 200030China Graduate University of Chinese Academy of Sciences Beijing 100049China Beijing Aerospace Command and Control Center Beijing 100094China Urumqi Astronomical Station of National Astronomical Observatories CASUrumqi 830011China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430070China

A prototype based on digital radio technology with associated open-loop Doppler signal processing techniques has been developed to measure a spacecraft's line-of-sight velocity. The prototype was tested in China's Chang'E-1 lunar mission relying on S-band telemetry signals transmitted by the sat-ellite,with results showing that the residuals had a RMS value of ～3 mm/s (1σ ) using 1-sec integration,which is consistent with the Chinese conventional USB (Unified S-Band) tracking system. Such preci-sion is mainly limited by the short-term stability of the atomic (e.g. rubidium) clock at the uplink ground station. It can also be improved with proper calibration to remove some effects of the transmission media (such as solar plasma,troposphere and ionosphere),and a longer integration time (e.g. down to 0.56 mm/s at 34 seconds) allowed by the spacecraft dynamics. The tracking accuracy can also be in-creased with differential methods that may effectively remove most of the long-term drifts and some of the short-term uncertainties of the uplink atomic clock,thereby further reducing the residuals to the 1 mm/s level. Our experimental tracking data have been used in orbit determination for Chang'E-1,while other applications (such as the upcoming YH-1 Mars orbiter) based on open-loop Doppler tracking will be initiated in the future. Successful application of the prototype to the Chang'E-1 mission in 2008 is believed to have great significance for China's future deep space exploration.

关键词： open-loop Doppler differential Doppler deep space navigation Chang’E-1

基于模糊评估和马尔可夫预测的供应链动态平衡记分卡

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系统工程理论与实践 2008年第4期28卷 57-64,80页

作者：郑培黎建强湖南大学工商管理学院长沙410082 香港城市大学商学院中国香港

传统的供应链绩效评价方法大多属于静态评价,而实际上供应链是一个动态系统,需要使用动态的绩效评价方法来进行考量.为了适应动态联盟整体绩效评价之需要,把传统的四维平衡计分卡扩展为五维动态平衡计分卡,然后运用层次分析法(AHP)来捕... 详细信息

传统的供应链绩效评价方法大多属于静态评价,而实际上供应链是一个动态系统,需要使用动态的绩效评价方法来进行考量.为了适应动态联盟整体绩效评价之需要,把传统的四维平衡计分卡扩展为五维动态平衡计分卡,然后运用层次分析法(AHP)来捕捉重要绩效驱动指标的扰动对于供应链整体绩效评价的影响,去除对绩效评价贡献较小的指标.在此基础上,利用模糊综合评估方法计算出供应链在各个时期的绩效评价结果.最后,结合Markov预测理论的决策支持功能,给出了动态供应链未来的绩效评价结果及发展趋势.计算实例表明本文提出的动态供应链绩效评价模型是合理、有效的,能够为供应链的合理分析和决策制定提供依据.

关键词：绩效评价动态平衡计分卡层次分析法(AHP) 模糊评估马尔可夫(Markov)预测

The Saturation Characteristics of Glucose Transport in Bovine Retinal Pigment Epithelium

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眼科学报 1998年第3期14卷 126-129页

作者： Chi Ho To kin Kwok Cheung Shing Hon Chiu Hon Ming lai Ka Shun Lung Laboratory of Ocular Physiology and Biochemistry Department of Optometry and Radiography The Hong Kong Polytechnic UniversityHung HomKawloonHong Kong

Purpose:To study the saturation characteristics of the glucose transport across the bovine retinal pigment epithelium(RPE).Methods:The bovine RPE preparations were munted with a modified Ussing *** L-[^(3)H]-glucose and 3-0-methyl-D-[^(14)C]-glucose fluxes across the RPE from the choroid to retina were studied at different glucose ***:The glucose transport was found to be stereospecific,with 3-0-methyl-D-glucose(MDG)being transported about three times faster than *** glucose transport showed typical saturation characteristics in Michaelis-Menten *** V_(max)and the K_(m)of corrected MDG were 2452 nmol cm^(-2)h^(-1)and 30.8 mM *** was shown that the glucose transport system was saturated at 61.6 ***:The saturation characteristics of the corrected MDG flux suggested that the capacity of glucose transport through the bovine RPE is immense.

关键词： ussing chamber retinal pigment epithelium glucose transport saturation kinetics

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中国股市指数与投资者情绪指数的相互关系

系统工程理论与实践 2012年第3期32卷 621-629页

作者：鲁训法黎建强香港城市大学管理科学系香港999077 中国科学技术大学管理学院合肥230026 南京信息工程大学经济管理学院南京210044

选取"新开交易账户数"作为投资者情绪的代理变量,应用ARMA-GARCH类模型研究了投资者情绪与股市收益率之间的相互关系.结果显示ARMA-GARCH类模型能有效拟合投资者情绪变化率和上证综合指数收益率的自相关性和异方差性.Granger因果检验表... 详细信息

选取"新开交易账户数"作为投资者情绪的代理变量,应用ARMA-GARCH类模型研究了投资者情绪与股市收益率之间的相互关系.结果显示ARMA-GARCH类模型能有效拟合投资者情绪变化率和上证综合指数收益率的自相关性和异方差性.Granger因果检验表明上证综合指数收益率是投资者情绪变化率的一个显著影响因子,而并没有发现投资者情绪的变化率对上证综合指数的收益率Granger因果显著.根据市场表现的不同特征,投资者利用这一信息调整情绪.当市场处于上升阶段时,投资者情绪会更为乐观,有更多新的投资者进入股市;当市场处于下降阶段时,投资者就会转变为较为悲观,场外的投资者就会处于观望状态,不急于进入股市,这样反映在股市上就是"新开交易账户数"减少.

关键词：上证指数投资者情绪指数新开交易账户数

Charge balance materials for homojunction and heterojunction OLED applications

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Frontiers of Optoelectronics 2009年第4期2卷 435-441页

作者： Louis M.LEUNG Yik-Chung LAW Michael Y.WONG Tik-Ho LEE kin Ming lai Lok-Yee TANG Department of Chemistry and Centre for Advanced Luminescence Materials Hong Kong Baptist University

In a homojunction device, a single organic layer assumes the multiple roles of hole, electron transportation, and emitter. Its ease in processing is highly desirable from the manufacturing point of view. In this paper, we shall describe the synthesis of a range of bipolar small molecules and conductive vinyl polymers for application in homojunction and heterojunction organic light emitting diodes（OLEDs）. The bipolar materials, in general, consist of three basic building blocks: an arylamine, a 1,3,4-oxadiazole, and a polycyclic aromatic moiety. The achievement of charge balance can be validated either by direct measurement of electron/hole mobility or indirectly via optimization of device properties.A series of conductive vinyl copolymers containing hole transporting N-（4-methoxyphenyl）-N-（4-vinylphenyl）naphthalen-1-amine（4MeONPA） and electron transporting 2-phenyl-5-（4-vinylphenyl）-1,3,4-oxadiazole（OXA）at different compositions was applied for heterojunction and homojunction OLEDs. For heterojunction devices employed the copolymers as the hole transporting layer and Alq3as the electron transporting and emitting layer,a maximum luminance and current efficiency of over 23000 cd/m2and 4.2 cd/A（PL of Alq3）, respectively, were achieved at the charge balance composition. Homojunction devices for the copolymers were demonstrated by the addition of rubrene as a dopant. The single layer devices at the optimal copolymer composition has ca 1500 cd/m2and 0.74 cd/A.

关键词： homojunction devices charge balance bipolar small molecules conductive vinyl copolymers

Long-Term Trends in Pre-Summer Daytime and Nocturnal Extreme Hourly Rainfall in a Coastal City of South China

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Journal of Tropical Meteorology 2023年第1期29卷 39-54页

作者：苏琳李俊鲁黄伟健冯志雄 School of Atmospheric Sciences Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiGuangdong 519082 China Key Laboratory of Tropical Atmospheric-Ocean System Ministry of EducationZhuhaiGuangdong 519082 China Earth OceanAtmosphere Sciences ThrustThe Hong Kong University of Science and Technology(Guangzhou):Guangzhou 511453 China Hong Kong Observatory Hong Kong Special Administrative Region(SAR)China Division of Environment and Sustainability The Hong Kong University of Science and TechnologyHong Kong SARChina Department of Mathematics The Hong Kong University of Science and TechnologyHong Kong SARChina

The long-term trends in the occurrence frequency of pre-summer daytime and nocturnal extreme hourly rainfall(EXHR) during 1988-2018 in Hong Kong and their spatial distributions are examined and analyzed. Despite a significant increasing trend observed in the occurrence frequency of pre-summer EXHRs during the investigated period,the increase in daytime and nocturnal EXHRs show distinct spatial patterns. Nocturnal EXHRs show uniform increasing trends over the entire Hong Kong. However, the increase in daytime EXHRs is concentrated over the northern or eastern areas of Hong Kong, indicating a downstream shift of pre-summer EXHRs in Hong Kong with regard to the prevailing southwesterly monsoonal flows in south China. The clustering of weather types associated with daytime and nocturnal EXHRs further reveals that the increase in EXHRs over Hong Kong are mainly contributed by the increase of the events associated with southwesterly monsoonal flows with relatively high speeds. During the past few decades, the southwesterly monsoonal flows at coastal south China have undergone a substantial weakening due to the increased surface roughness induced by the urbanization over the Guangdong-Hong Kong-Macao Greater Bay Area since 1990s,leading to enhanced low-level convergence and thus significant increase in EXHRs at coastal south China. Meanwhile,daytime sea-wind circulation at coastal south China is markedly enhanced during the investigated period, which is the main reason for the northward shift of daytime EXHRs in Hong Kong. In addition, the blocked southwesterly monsoonal flows at coastal south China are detoured eastward, leading to stronger convergence and increase in EXHRs at eastern coast of Hong Kong, especially during daytime, when the easterly sea winds prevail at the region.

关键词： extreme hourly rainfall diurnal rainfall cycle linear trend coastal Pearl River Delta

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“新常态”下的中国天然气消费分析及预测

运筹与管理 2019年第6期28卷 175-183页

作者：柴建王亚茹 kin Keung-lai 西安电子科技大学经济与管理学院陕西西安710126 陕西师范大学国际商学院陕西西安710062 香港城市大学管理科学系香港999097

作为一种优质、高效的绿色能源,天然气在中国能源结构中所占比重逐渐增加。但可再生能源的崛起使得天然气成为过渡能源的选择,天然气消费量的增长趋势不明晰,因此相关企业及部门需要合理、准确的天然气需求预测模型为未来的工作提供指... 详细信息

作为一种优质、高效的绿色能源,天然气在中国能源结构中所占比重逐渐增加。但可再生能源的崛起使得天然气成为过渡能源的选择,天然气消费量的增长趋势不明晰,因此相关企业及部门需要合理、准确的天然气需求预测模型为未来的工作提供指导性信息。基于此,本文首先从经济水平、产业结构、能源结构、天然气价格等方面选取影响天然气消费的12个因素。其次,运用贝叶斯模型平均(BMA)法构建了一个包含相关文献中常用的6个影响因素的基准模型,针对该模型,围绕影响天然气消费量的各种因素,以逐个添加的方式建立对比模型,从备选模型中选出预测精度最高的对未来天然气消费量进行预测。最后,将BMA模型与ARIMA模型、ETS模型、BVAR模型、逐步回归模型以及等权重加权平均模型的预测精度进行对比。结果表明,最优的BMA模型包含了涉及经济水平、产业结构、能源结构、人口因素、天然气价格、天然气供给六个方面9个影响因素,其预测精度优于对比预测模型,且该模型预测2022年天然气消费量将达到3254.153亿立方米,年均增长率为8%。

关键词：贝叶斯模型平均影响因素模型选择情景分析天然气消费量预测

Outcome of 1355 consecutive transabdominal chorionic villus samplings in 1351 patients

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Chinese Medical Journal 2005年第20期118卷 1675-1681页

作者： LAU Tze kin LEUNG Tak Yeung fung Tak Yuen CHAN Lin Wai Daljit S SAHOTA LEUNG Tse Ngong Fetal Medicine Unit Department of Obstetrics and Gynaecology Prince of Wales Ho spitalChinese University of Hong KongShatinHong Kong SARChina

Background The true risk of choronic villus sampling(CVS)is poorly *** objective of this study was to review the clinical outcome of transabdominal CVS performed in a university teaching unit,with an emphasis on the complication *** A comprehensive audit database was maintained for 1351 pregnant women,including 17 sets ot twin pregnancies,who had a *** and outcome of all CVSs made in the unit between May 1996 and May 2004 were *** CVSs were performed by one of 5 operators using the identical *** All procedures were performed transabdominally.A total of 1355 CVSs were performed because there were 4 dichorionic twin pregnancies which required 2 *** mean gestation at CVS was(11.8+0.7)weeks,and 97.3%of the procedures were performed between 11 and 13 completed *** majority(96.2%)required only 1 puncture to achieve correct needle *** procedure failed to obtain an adequate sample in 4 subjects(0.30%).A total of 1351 chromosomal studies were requested and there was 1 case(0.07%)of culture *** results of chromosomal studies were available within 14 days in 36.7%of the cases and within 21 days in 94.0%.Overall,77 chromosomal abnormalities(5.7%)and 5 cases of thalassemia major were *** outcome was unknown in only 13 singleton subjects(0.96%).In the remaining 1355 fetuses,there were 76 pregnancy terminations(5.56%),10 fetal losses with obvious obstetric causes(0.73%),and 21 potentially procedure-related fetal losses(1.54%).In the last group,the majority had one or more co-existing obstetric *** background fetal loss rate for pregnancies at similar gestational age in the unit was about 0.8%.Therefore,the procedure-related fetal loss rate was estimated to be at the maximum of 0.74%.Conclusions In experienced hands,first trimester transabdominal CVS is an accurate and safe invasive prenatal diagnostic *** should be one of the treatment options available to pregn

关键词： chorionic villus sampling postoperative complication pregnancy outcome

不确定条件下应急管理人力供应链多功能资源配置鲁棒优化问题

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系统工程理论与实践 2015年第3期35卷 736-742页

作者：朱雷黎建强汪明湖南大学商学院长沙410000 香港城市大学商学院香港999077 香港东华学院商学院香港999077

在紧急甚至灾难状态下,应急管理物资及人力需求都是爆发性的,为了满足应急状况的不确定需求,实现应急人力的合理管理和配置,借鉴成熟的供应链理论,强化应急管理人力供应链的协调配置能力有很大的理论及现实意义.本文简述了人力供应链的... 详细信息

在紧急甚至灾难状态下,应急管理物资及人力需求都是爆发性的,为了满足应急状况的不确定需求,实现应急人力的合理管理和配置,借鉴成熟的供应链理论,强化应急管理人力供应链的协调配置能力有很大的理论及现实意义.本文简述了人力供应链的发展,重点讨论应急状态下连续性的人力服务需求.需求到来及其长度都是不确定的,多能力的专业人员应当被合理配置以优化服务.在本文中,我们提出了一个不确定条件下的网络优化模型,强调了多能力专业人员的资源分配.随机规划模型及鲁棒优化技术将被运用来处理不确定需求及网络优化,我们也将讨论其他特殊情况如服务取消,服务延长,提前结束等,我们的模型将有较为普遍的适应性.

关键词：应急管理人力供应链鲁棒优化