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Multiparty quantum secret sharing of classical and quantum messages

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Progress in natural Science:Materials International 2007年第1期17卷 26-31页

作者： CHEN Pan, DENG Fuguo and LONG Guilu ( Key Laboratory for Quantum information and Measurements, and Department of Physics, Tsinghua university, beijing 100084, china Key Laboratory of Beam technology and Material Modification, MOE, Institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, beijing Normal university, beijing 100875, china beijing Radiation Center, beijing 100875, china Key Laboratory for Atomic and Molecular Nano-Sciences, Tsinghua university, beijing 100084, china) Key Laboratory for Quantum information and Measurements Department of Physics Tsinghua University Beijing 100084 China Key Laboratory of Beam technology and Material Modification Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear Physics Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China Key Laboratory for Atomic and Molecular Nano-Sciences Tsinghua University Beijing 100084 China

A scheme for multiparty quantum secret sharing of classical and quantum messages is proposed by using entanglement swapping. This scheme can distribute not only the classical information but also the quantum informati... 详细信息

关键词： quantum secret sharing classical message quantum message EPR pair.

Robust multiuser MIMO scheduling algorithms with imperfect CSI

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Science china(information Sciences) 2012年第4期55卷 815-826页

作者： MAO JunLing 1,3,GAO JinChun 1,3,LIU YuanAn 1,3,XIE Gang 2,3 & ZHANG Jian 1,3 1 School of Electronic Engineering,beijing university of Posts and Telecommunications,beijing 100876,china 2 School of information and Communication Engineering,beijing university of Posts and Telecommunications,beijing 100876,china 3 Key Lab of Universal Wireless Communications,Ministry of Education,beijing university of Posts and Telecommunications,beijing 100876,china School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing China Key Lab of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing China School of information and Communication Engineering Beijing University of Posts and Telecommunications Beijing China

Robust multiuser multiple-input-multiple-output (MIMO) scheduling algorithms are proposed in this *** imperfect channel state information (CSI),traditional scheduling algorithms for the multiuser MIMO system based on the zero forcing precoding scheme will lose some performance due to the multi-user interference (MUI).In order to improve the system average throughput,we study the robust multiuser MIMO scheduling problem with imperfect *** the average capacity formula,we derive a robust factor which can transform the robust multiuser MIMO scheduling problem into the traditional one,thus most existing non-robust scheduling algorithms can be robust if this factor is *** results show that compared with the traditional algorithms,the proposed robust algorithms can improve the system average throughput significantly under the CSI error environment.

关键词： multiuser MIMO (MU-MIMO) scheduling robust imperfect CSI

Subsidence control and farmland conservation by solid backfilling mining technology

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中国有色金属学会会刊：英文版 2011年第S3期21卷 665-669页

作者： GUO Guang-li1, 2, FENG Wen-kai3, ZHA Jian-feng1, 2, 3, LIU Yuan-xu1, 2, WANG Qiang1, 2 1. Key Laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping, china university of Mining and technology, Xuzhou 221116, china 2. Jiangsu Key Laboratory of resources and Environmental information Engineering, china university of Mining and technology, Xuzhou 221116, china 3. State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu university of technology, Chengdu 610059, china Key Laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China Jiangsu Key Laboratory of resources and Environmental information Engineering China University of Mining and Technology Xuzhou 221116 China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

Solid backfilling mining technology, which decreases the height of fissure zone and caving zone, and alleviates the subsidence, is a new technology for farmland conservation. Based on the situation analysis of farmland destruction in mining area, three ways for farmland protection were proposed. In order to improve the feasibility of this technology, the limited filling materials should be used to increase resources recovery ratio, and then the surplus materials could be backfilled into goaf. An index, namely farmland conservation ability, was put forward to optimize the ways for farmland conservation. At last, the Wanbei coal mine was taken as a case for farmland conservation. It was shown that 3240 t dull coal was substituted and 52 hm2 farmland was conserved by solid backfilling mining in this coal mine.

关键词： solid backfilling farmland conservation mining subsidence equivalent mining height

Effect of coherent-light phase on tunneling process

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Journal of university of Science and technology beijing 2003年第4期10卷 61-64页

作者： Peng FengApplied Science School, university of Science and technology beijing, beijing 100083, china Univ Sci & Technol beijing Appl Sci Sch Beijing 100083 Peoples R China

The coherent-light-driven tunneling in double quantum wells has been *** electrons are coupled to a system of phonons and subjected to the two beams of coherentlyoptical waves. By adopting a gauge to both the external field and the phonon field, the phonon fieldoperators in the Schrodinger equations are eliminated. In this way, an expression of the tunnelingcurrent is conveniently derived considering the relaxation effect. It is shown that under theintense laser field, the tunneling current oscillates rapidly with time at low temperature. Theduration of the oscillations is related to the temperature. By adjusting the phase difference of thetwo light-beams, the oscillation frequency can be modulated.

关键词： tunneling current quantum wells gauge transformation

Mining subsidence control by solid backfilling under buildings

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中国有色金属学会会刊：英文版 2011年第S3期21卷 670-674页

作者： ZHA Jian-feng1, 2, 3, GUO Guang-li1, 2, FENG Wen-kai3, WANG Qiang1, 2 1. Key Laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping, china university of Mining and technology, Xuzhou 221116, china 2. Jiangsu Key Laboratory of resources and Environmental information Engineering, china university of Mining and technology, Xuzhou 221116, china 3. State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu university of technology, Chengdu 610059, china Key Laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China Jiangsu Key Laboratory of resources and Environmental information Engineering China University of Mining and Technology Xuzhou 221116 China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

Solid backfilling mining can reduce the buildings' damage caused by mining greatly. The reduction of subsidence value, the slow advancing speed and the subsidence caused by backfilling body compaction are the main reasons that solid backfilling mining velocity decreases significantly. Based on the research of mechanism, some principles on subsidence control of solid backfilling mining under buildings were proposed. The equivalent mining height was designed according to the fortification criteria of buildings and their attachment structures, which enables the ground movement and deformation caused by mining to be less than the corresponding fortification criteria.

关键词： solid backfilling mining subsidence control mining under buildings

Research on the damage of the Great Wall of Ming Dynasty in beijing by remote sensing

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Science china(Technological Sciences) 2008年第S1期51卷 195-202页

作者： LI XiaoJuan,GONG HuiLi,ZHANG Ou,ZHANG WeiGuang & SUN YongHua The Key Lab of 3D information Acquisition and Application,MOE,the Key Lab of beijing resource Envi-ronment and GIS,and College of resource Environment & Tourism,Capital Normal university,beijing 100037,china The Key Lab of 3D information Acquisition and Application MOE the Key Lab of Beijing Resource Environment and GIS and College of Resource Environment & Tourism Capital Normal University Beijing China

Using aerial photos and high resolution satellite images of the year of 2004,this paper establishes remote sensing interpretation marks of the Great Wall of Ming Dynasty's damaged levels. Based on field survey and remote sensing survey in 1984,we analyzed present situation and changing characteristics being of the Great Wall of Ming Dynasty in beijing. The results show that about 7.02% of the wall is well-preserved (about 25861 m); 31.5% of the wall is slightly or moderately dam-aged (about 115989 m); 61.5% of the wall is badly damaged (about 226379 m). This paper analyzes the dynamic change of the Great Wall of Ming Dynasty. It shows that the damaged situation of the Great Wall of Ming Dynasty in beijing is serious. From 1984 to 2004,the well-preserved wall is decreased by 33206 m (decreased by 56%); badly damaged wall increased by 51207 m (increased by 67%). Finally,this paper analyzes the influence factors of damaging Great Wall. The conclusion is as follows: The damaged Great Wall is generally near the roads and villages,small slope,and easily arriving land.

关键词： the Great Wall of Ming Dynasty remote sensing interpreting damage dynamic change spatial analysis

Series-based approximate approach of optimal tracking control for nonlinear systems with time-delay

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Progress in natural Science:Materials International 2008年第12期18卷 1571-1576页

作者： Gongyou Tang~a Mingqu Fan~(a,b) a College of information Science and Engineering,Ocean university of china,Qingdao 266100,china b College of information and Engineering,Shandong university of Science and technology,Jinan 250031,china College of information Science and Engineering Ocean University of China Qingdao 266100 China College of information and Engineering Shandong University of Science and Technology Jinan 250031 China

The optimal output tracking control (OTC) problem for nonlinear systems with time-delay is *** a series-based approx- imate approach,the original OTC problem is transformed into iteration solving linear two-point boundary value problems without time- *** OTC law obtained consists of analytical linear feedback and feedforward terms and a nonlinear compensation term with an infinite series of the adjoint *** truncating a finite sum of the adjoint vector series,an approximate optimal tracking control law is obtained.A reduced-order reference input observer is constructed to make the feedforward term physically *** exam- ples are used to test the validity of the series-based approximate approach.

关键词： Nonlinear systems Time-delay Tracking control Optimal control Observer

Cretaceous-Early Eocene Tectonic Stress Field in china

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Acta Geologica Sinica(English Edition) 1989年第3期63卷 227-239页

作者： Wan Tianfeng and Zhu Hong china university of Geosciences, beijing, china 2Wan Tianfeng male born in 1938 engaged in geological education since 1959 and now is a professor of the Teaching and Research Group of Structural Geology China University of Geosciences Beijing 100083. china university of Geosciences Beijing China

The Cretaceous-early Eocene tectonic stress field in china was reconstructed using the data of 369 largeand medium-scale flexural folds and 157 joint sets. It was found that the maximum compressive principal stress axis in eastern china dips 32° NE (nearly horizontal), and strikes SW 212°, whereas that in western china dips 15° NE (also nearly horizontal) and trends SW 195°. The estimation of the dip angles of fold limbs and the palaeotectonic stress values indicates that there was a tendency of gradual weakening of tectonism from southwestern to northeastern china in the Cretaceous-early Eocene. At the depth of 2-3 km, the differential stress value changes from 183 MPa in Tibet to 100 MPa in North and East china.The authors consider that the tectonic stress of this period was related to the north-northeastward movement and push of the Indian-Australian plate.

关键词： Cretaceous-Early Eocene Tectonic Stress Field in china

A study on determining the location of groundwater divide using a mathematical morphology method

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Science china(Technological Sciences) 2006年第Z2期49卷 141-148页

作者： PAN Yun, GONG Huili, DUAN Fuzhou & HU Zhuowei Key Laboratory of 3D information Acquisition and Application, Ministry of Education, Capital Normal university, beijing 100037, china Key Laboratory of resource Environment and GIS of beijing, Capital Normal university, beijing 100037, china Capital Normal Univ Minist Educ Key Lab D Informat Acquisit & Applicat 3 Beijing 100037 Peoples R China Capital Normal Univ Key Lab Resource Environm Beijing 100037 Peoples R China Capital Normal Univ GIS Beijing Beijing 100037 Peoples R China

Placement of a groundwater divide indicates sink areas and spatial distribution, knowledge of which helps in the mapping of regional aquifer properties and the management of groundwater resources. By applying mathematical morphology to a conceptual model of a watershed and characteristic erosion and dilation operations, this paper proposes a structuring element with which to extract the shape and location of groundwater divide. With due consideration to watershed linearity, a structuring element with three origins is designed to connect watershed points. After erosion, closing, and dilation operations, the groundwater divide is determined; the results indicate this method's feasibility and accuracy.

关键词： groundwater divide, mathematical morphology, structuring element.