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A community-centric approach to automated service composition

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Science China(Information sciences) 2010年第1期53卷 50-63页

作者： LIU XuanZhe1,2. HUANG Gang1,2.& MEI Hong1,2.1School of Electronics Engineering and Computer Science, Peking University, beijing 100871, China 2.1} {2. of High Confidence Software Technologies, Ministry of Education, Peking University, beijing 100871, China School of Electronics Engineering and Computer Science Peking University Beijing China key laboratory of High Confidence Software Technologies Ministry of Education Peking University Beijing China

In the recent years, the web has kept growing rapidly and undergone tremendous changes towards a user-centric environment. With the proliferation of services available on the Internet, millions of users are able to voluntarily participate in and collaborate for their own interests and benefits by means of service composition. However, due to the ever increasing number of services, it then becomes a challenging issue to enable the users to rapidly select and compose the proper services. In this paper, we propose an approach which utilizes service communities for automated service composition. This paper makes three contributions. Firstly, we propose the service community architecture and identify two key components to facilitate service discovery and composition. Secondly, assisted by the service community, we provide two composition types to help users explore the space of potential composition opportunities without having to understand too many details of individual candidate services. Finally, we evaluate our approach by performance analysis and provide a web-based prototype that lowers the entry barrier for the users.

关键词： services computing service composition service community

Monitoring Glacier and Supra-glacier Lakes from space in Mt. Qomolangma Region of the Himalayas on the Tibetan Plateau in China

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Journal of Mountain Science 2009年第3期6卷 211-220页

作者： YE Qinghua ZHONG Zhenwei KANG Shichang Alfred Stein WEI Qiufang LIU Jingshi key laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences (CAS) Beijing 100085 China State key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China International Institutefor Geo-Information Science and Earth Observation (ITC) PO Box 67500 AA Enschede The Netherlands

Because of the large number and remoteness, satellite data, including microwave data and optical imagery, have commonly been used in alpine glaciers surveys. Using remote sensing and Geographical Information System （GIS） techniques, the paper presents the results of a multitemporal satellite glacier extent mapping and glacier changes by glacier sizes in the Mt. Qomolangma region at the northern slopes of the middle Himalayas over the Tibetan Plateau. Glaciers in this region have both retreated and advanced in the past 35 years, with retreat dominating. The glacier retreat area was 3.2. km2.（or o.75 km^2.yr^-1 during 1974 and 1976, 8.68 km^2.（or 0.36 km^2.yr^-1 during 1976 and 1992. 1.44 km^2.（or 0.12.km^2.yr^-1） during 1992.2.oo. 1.14 km^2.（or 0.2. km^2.yr^-1 during 2.00-2.03, and 0.52.km^2.（or 0.07 km^2.yr^-1 during 2.03-2.08, respectively. While supra-glacier lakes on the debris-terminus of the Rongbuk Glacier were enlarged dramatically at the same time, from 0.05 km^2.in 1974 increased to 0.71 km^2.in 2.08, which was more than 13 times larger in the last 35 years. In addition, glacier changes also showed spatial differences, for example, glacier retreat rate was the fastest at glacier termini between 5400 and 5700 m a.s.l than at other elevations. The result also shows that glaciers in the middle Himalayas retreat almost at a same pace with those in the western Himalayas.

关键词： Glacier lake Remote Sensing Mr. Qomolangma region Himalayas Tibetan Plateau

Variations of IMF sector structure with the sunspot cycle

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Variations of IMF sector structure with the sunspot cycle

Nightside field-aligned current during the April 6,2.00 superstorm

第十二届全国日地空间物理学术讨论会

作者： Aimin Du~(1,2. Wenyao Xu~1 Xueshang Feng~2.J.Kan~3 1 Institute of Geology and Geophysics,chinese academy of sciences,beijing 10002. 2.State {2. {2. for space weather,chinese academy of sciences,beijing 100080 3 Geophysical Institute,University of Alaska Fairbanks,AK,USA

＜正＞Using the OMNI data of the interplanetary magnetic field （IMF） near earth orbit during the period of 1976-2.05,we study quasi-periodic variations of the IMF sector *** spectrum analysis indicates that the Bx w...

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Nightside field-aligned current during the April 6,2000 supe...

Dislocation structure of the crust-mantle boundary and low-velocity body within the crust beneath the Dabie Shan collision orogen

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： WANG Yuan~(1,2.,HONG MingHua~(1*),CHEN GengXiong~1,XU WenYao~1,DU AiMin~(1,3), ZHAO XuDong~(1,2.,LIU XiaoCan~4 & LUO Hao~(1,2. 1 Institute of Geology and Geophysics,chinese academy of sciences,beijing 10002.,China 2.Graduate University of chinese academy of sciences,beijing 100049,China 3 State key laboratory of space weather,beijing 100190,China 4 Institute of Geophysics,China Earthquake Administration,beijing 100081,China

Using the east-west geomagnetic disturbance fields observed from stations at mid-latitudes,we investigate the characteristics of field-aligned currents on the nightside during the April 6,2.00 *** results indicate that there is an eastward disturbance on the nightside of Northern Hemisphere during the main phase of magnetic storm,while the interplanetary magnetic field (IMF) is continued *** positive disturbances in the postmidnight are larger than that in the *** suggests that upward field-aligned currents develop on the nightside,when the IMF is directed *** peak of upward field-aligned currents is located in postmidnight,and it will be more obvious at substorm *** get the conclusion that both partial ring current and region-2.field-aligned current shift to dusk *** upward region-2.current is decreased at substorm onset,and intensified after *** also investigate the relationship between the upward field-aligned currents on the nightside and the auroral electrojets at high *** shows a good correspondence between region-2.current and the westward electrojet in the *** suppose that they are both associated with the convection electric field.

关键词： main phase field-aligned current auroral electrojet substorm current wedge

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Science China Earth sciences 2005年第7期48卷 875-885页

作者： LIU Qiyuan1, Rainer Kind2. CHEN Jiuhui1, YUAN Xiaohui2. LI Shuncheng1, GUO Biao1, Kurt Wylegalla2.& LAI Yuangen1 1. State key laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, {2. 10002., China 2. GeoForschungZentrum Potsdam, Telegrafenburg A17, Potsdam, D-14473, Germany State key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China GeoForschungZentrum Potsdam Telegrafenburg A17 Potsdam D-14473 Germany

From April of 2.01 to March of 2.02. a passive seismic array experiment was car- ried out in the Dabie Shan and its adjacent region. In this experiment, totally 34 broadband seismic stations were deployed along a profile across the Dabie Shan orogen and North-China platform. This profile is about 500 km long from Cuilin (34°40′N, 114°49′E), Henan Province, to Dajipu (30°2.′N, 115°03′E), Hubei Province. The space between stations is about 3?8 km in the Dabie Shan orogenic belt and about 15?2. km in other area. The receiver function profile and S-wave velocity structure of the crust and upper mantle down to 100 km depth along the profile are investigated in terms of the receiver function techniques (Liu et al., 1996, 2.00). Our results show that the crust beneath the Dabie Shan orogen has an obviously asymmetric blocked structure in the direction perpendicular to the mountain strike. The maximal crustal thickness reaches to 42.km. The crust-mantle boundary has a dislocation structure correlated to the crustal blocks and the largest offset reaches to 8 km. In the kernel of the orogen exists a low-velocity body inside the crust, which is separated into two parts corresponding to the South Dabie and North Dabie on the surface, respectively. Probably a vertical divergent movement between both took place in history. The crust below this low-velocity area has a positive gradient velocity structure with the depth, and the upper mantle down to the depth of 70 km has the lower S-wave velocity than its both sides. Beneath the Dabie Shan, however, a high-velocity anomaly exists in the upper mantle below 70 km.

关键词： receiver function low-velocity body Moho discontinuity Dabei Shan collision orogen.

Data-aided synchronization algorithm dispensing with searching procedures for UWB communications

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Science China(Information sciences) 2012年第4期55卷 778-788页

作者： REN ZhiYuan 1,JIANG Ting1,ZHONG Yi 2.& ZHAO ChengLin 1 1 key laboratory of Universal Wireless Communications,Ministry of Education of China Wireless Network laboratory,{2. University of Posts and Telecommunications,{2. 100876,China 2.School of Information Engineering,North China University of Technology,{2. 100041,China key laboratory of Universal Wireless Communications Ministry of Education of China Wireless Network laboratory Beijing University of Posts and Telecommunications Beijing China School of Information Engineering North China University of Technology Beijing China

Rapid and accurate synchronization constitutes a major challenge in deploying Ultra-Wideband impulse radio (UWB-IR) for indoor wireless *** paper develops a data-aided (DA) synchro-nization algorithm dispensing with searching procedures for UWB-IR *** adopting a stream of alternating orthogonal pulses,frame-level synchronization can be achieved without channel ***-out utilizing any searching procedure,the timing offset estimator is obtained in a closed *** exhaustive search can be avoided,both computational complexity and synchronization time are *** and comparisons are provided to illustrate the advantages of our design over the alternatives.

关键词： Ultra-Wideband impulse radio synchronization dispensing with searching procedures searching space data-aided estimation

New development thoughts on the bio-inspired intelligence based control for unmanned combat aerial vehicle

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Science China(Technological sciences) 2010年第8期53卷 2025-2031页

作者： DUAN HaiBin 1 ,SHAO Shan 2.,SU BingWei 3 &ZHANG Lei 41 State key laboratory of Science and Technology on Holistic Flight Control,School of Automation Science and Electrical Engineering, {2. University of Aeronautics and Astronautics,{2. 100191,China 2.Flight Control Department,Shenyang Aircraft Design and Research Institute,Shenyang 110035,China 3 {2. Institute of Near space Vehicle’s System Engineering,{2. 100076,China 4Integration and Project Section,Air Force Equipment academy,{2. 100085,China State key laboratory of Science and Technology on Holistic Flight Control School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing China Flight Control Department Shenyang Aircraft Design and Research Institute Shenyang China beijing Institute of Near space Vehicle’s System Engineering Beijing China Integration and Project Section Air Force Equipment Academy Beijing China

Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence,and unmanned combat aerial vehicle(UCAV),owing to its potential to perform dangerous,repetitive tasks in remote and hazardous,is very promising for the technological leadership of the nation and essential for improving the security of *** the basis of introduction of bioinspired intelligence and UCAV,a series of new development thoughts on UCAV control are proposed,including artificial brain based high-level autonomous control for UCAV,swarm intelligence based cooperative control for multiple UCAVs,hy-brid swarm intelligence and Bayesian network based situation assessment under complicated combating environments, bio-inspired hardware based high-level autonomous control for UCAV,and meta-heuristic intelligence based heterogeneous cooperative control for multiple UCAVs and unmanned combat ground vehicles(UCGVs).The exact realization of the proposed new development thoughts can enhance the effectiveness of combat,while provide a series of novel breakthroughs for the intelligence,integration and advancement of future UCAV systems.

关键词： bio-inspired intelligence unmanned combat aerial vehicle(UCAV) artificial brain autonomous control bayesian network bio-inspired hardware heterogeneous cooperative control

Anchimetamorphism of the Neoproterozoic and the Lower Paleozoic along the Profile of Yuanguping in Western Hunan Province, China

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Acta Geologica Sinica(English Edition) 2004年第1期78卷 170-176页

作者： WANG Hejing, CHEN Tao, WANG Huan and ZHANG Zuqing"Orogene and Crust Evolution " key laboratory of the Ministry of Education of China School of Earth and {2. {2., Peking University, beijing 100871 Peking Univ Sch Earth & Space Sci Oregene & Crust Evolut Key Lab Minist Educ Beijing 100871 Peoples R China

The Neoproterozoic and Lower Paleozoic along the profile of Yuanguping in western Hunan Province, China underwent anchimetamorphism. The illite crystallinity (IC) of the <2.μm fractions ranges from 0.2.-0.34°△2.fo... 详细信息

The Neoproterozoic and Lower Paleozoic along the profile of Yuanguping in western Hunan Province, China underwent anchimetamorphism. The illite crystallinity (IC) of the 2.μm fractions ranges from 0.2.-0.34°△2.for the Neoproterozoic to 0.2.-0.35°△A2. for the Lower Paleozoic (calibrated with the Kisch IC set, Kisch, 1991). This indicates that the metamorphic grade of the Neoproterozoic and Lower Paleozoic is the anchizone. The peak metamorphic temperature is estimated to be 2.0-2.0℃. This result does not agree with the greenschist or subgreenschist facies of the Banxi Group, nor with the lower-greenschist facies or sedimentary cover of the Sinian to Lower Paleozoic, as most previous researchers thought. The illite (K-mica) b0 values range from 0.9074 to 0.8963 (nm) for the Neoproterozoic and the Lower Paleozoic. Based on cumulative frequency curves of the illite (K-mica) b0, the peak metamorphic pressure of the Banxi Group was derived to be of a type that is slightly higher than that of the N. New Hampshire low-intermediate pressure type. Most illites occur as the 2.1 polytype and some in the Neoproterozoic as a mixture of the 2.1+1M types. The distributions of coherent scanning domains (CSDs) of illites along the profile, measured with the XRD method, display a lognormal model and spread out with decreasing Kubler Index of IC. It indicates that illites underwent an Ostwald ripening. The post-anchimetamorphic structural movement not only results in a series of faults but also induces the lattice strain in minerals along the faults and hence impacts the illite crystallinity and causes diagenetic samples to occur within the anchizone. Compared with the cases in eastern and central Hunan Province, the Neoproterozoic and Lower Paleozoic rocks in the west underwent a lower-temperature anchimetamorphism with a pressure lower than that in the east and higher than that in the center of Hunan Province.

关键词： illite crystallinity polytypism cell dimension lattice strain domain size anchimetamorphism,Neoproterozoic Lower Paleozoic

Geochemical characteristics and tectonic implications of HP-UHP eclogites and blueschists in southwestern Tianshan, China

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Progress in Natural Science:Materials International 2006年第6期16卷 624-632页

作者： AI Yongliang, ZHANG Lifei, LI Xuping and QU Junfeng (MOE key laboratory of Orogenic Belt and Crust Evolution, School of Earth and {2. {2., Peking University, beijing 100871, China School of Geo{2. and Resources, China University of Geo{2., beijing 100083, China) MOE key laboratory of Orogenic Belt and Crust Evolution School of Earth and Space Sciences Peking University Beijing 100871 China School of Geosciences and Resources China University of Geosciences Beijing 100083 China

Four rock assemblages in correspondence with two different tectonic settings have been recognized in the NEE-SWW extending HP-UHP metamorphic belt in southwestern Tianshan, northwest China. Eclogite assemblage EC1 is geochemically akin to alkaline within-plate oceanic island basalt (OIB). EC2.shows affinity to enriched mid-oceanic ridge basalt (EMORB). Rare earth element (REE) and other immobile trace element characteristics of blueschist assemblage BS1 resemble those of normal mid-oceanic ridge basalt (NMORB). These three assemblages are likely formed on a seamount setting, and the prevalent presence of carbonate minerals and om-phacite quartzite stripes/gobbets suggests ancient pelagic sediments including marls are probably developed upon the basaltic seamount. Whereas the geochemical characteristics of BS2.assemblage are of volcanic arc basalt-type. The seamount with the pelagic sediments on it is brought into the subduction zone, and volcanic arc basalts formed on the active continental margin and trench sediments are eroded and enwrapped in the subducting mass, they are altogether subjected to high to ultrahigh pressure metamorphism and subsequent exhumation towards surface. The HP-UHP metamorphic belt is thus interpreted as a subduct ion-accretionary complex formed by tectonic juxtaposition and imbrication of seamount, seafloor, trench and volcanic arc sequences during oceanic crust subduction.

关键词： southwestern Tianshan HP-UHP metamorphic belt snbduction-accretion complex trace element geochemistry.