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QoS-aware scheduling algorithm in relay-assisted LTE-A system

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The Journal of China Universities of Posts and Telecommunications 2013年第5期20卷 16-21页

作者： CHUAI gang YU xiao-liang School of Information and Communication Engineering Beijing University of Posts and Telecommunications Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications

This paper details on the uplink scheduling algorithm for long term evolution advanced （LTE-A） system with relays. While emulating quality of service （QoS）-aware services with different bit-rate and delay budget requirements for the upstream direction, a new QoS-aware scheduling algorithm for in-band relays is proposed. In this work, an improved scheduling metric calculation method and bit-rate guarantee scheme is applied. Moreover, this algorithm proposes an efficient scheme for the backhaul link allocation which allows information of the most backlogged users to be transmitted first. Finally, this paper concludes with simulation results to demonstrate how the proposed resource allocation strategy improves the performance of the system.

关键词： relay station scheduling algorithm guaranteed bit rate (GBR) backhaul link access link

An investigation of collisions between fiber positioning units in LAMOST

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Research in Astronomy and Astrophysics 2016年第4期16卷 107-112页

作者： xiao-Jie Liu gang Wang Key Laboratory of Optical Astronomy National Astronomical ObservatoriesBeijing 100012China University of Chinese Academy of Sciences Beijing 100049China

The arrangement of fiber positioning units in the LAMOST focal plane may lead to collisions during the fiber allocation process, To avoid these collisions, a software-based protection system has to abandon some targets located in the overlapping field of adjacent fiber units. In this paper, we first analyze the probability of collisions between fibers and infer their possible reasons. It is useful to solve the problem of collisions among fiber positioning units so as to improve the efficiency of LAMOST. Based on this, a collision handling system is designed by using a master-slave control structure between the micro control unit and microcomputer. Simulated experiments validate that the system can provide real-time inspection and swap information between the fiber unit controllers and the main controller.

关键词： methods: statistical -- telescopes -- instrumentation: detectors -- methods: data analysis --methods: observational

Influence of multiple structural parameters on interior ballistics based on orthogonal test methods

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Defence Technology（防务技术） 2019年第5期15卷 690-697页

作者： chao-bin Hu xiao-bing Zhang School of Energy and Power Engineering Nanjing University of Science and Technology

Influence of multiple structural parameters on the performance of a gun launch system driven by highpressure reactive gases is important for structural design and performance adjustment.A coupled lumped parameter model was utilized to predict the propellant combustion,and a dynamic finite element method was applied to approximate the mechanical interactions between the projectile and the *** combustion and the mechanical interactions were coupled through a user subroutine interface in *** correctness and the capability of the finite element approximations in capturing small structural changes were validated by comparing predicted resistance with *** on the coupled model,the influence of structural parameters of a medium-caliber gun on the system performance was *** order to reduce the research costs,orthogonal tests were designed to investigate the comprehensive effects of the *** to statistical analysis,the important order of the structural parameters on the launching process was *** results indicate that the influence of the width of the rotating band stands out among the studied parameters in the *** work provides a method to investigate the influence of multiple parameters on system performance and gives guidance for controlling the system performance.

关键词： Multiple parameters Coupled model Combustion Sensitivity analysis Orthogonal test

Assessing the quality of metamodels

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Frontiers of Computer Science 2013年第4期7卷 558-570页

作者： Zhiyi MA xiao HE chao LIU Software Institute School of Electronics Engineering and Computer Science Peking University Beijing 100871 China Ministry of Education Key Laboratory of High Confidence Software Technologies (Peking University) Beijing 100871 China School of Computer and Communication Engineering University of Science and Technology Beijing Beiiing 100083 China School of Economics Shandong University of Finance and Economics Jinan 250202 China

The complexity and diversity of modern software demands a variety of metamodel-based modeling languages for software development. Existing languages change continuously, and new ones are constantly emerging. In this situation, and especially for metamodel-based modeling languages, a quality assurance mechanism for metamodels is needed. This paper presents an approach to assessing the quality of metamodels. A quality model, which systematically characterizes and classifies quality attributes, and an operable measuring mechanism for effectively assessing the quality of metamodels based on the quality model, are pre- sented, using UML as the main example.

关键词： quality assessment metamodels metric

Persistent organochlorine residues in sediments of Haihe River and Dagu Drainage River in Tianjin, China

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Journal of Environmental Sciences 2005年第5期17卷 731-735页

作者： DING Hui LI Xin-gang LIU Hun WANG Jun SHEN Wei-ran SUN Yi-chao SHAO xiao-long School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Tianjin Environmental Protection Bureau Tianjin 300191 China

Persistent organochlorine compounds were analyzed by means of GC-ECD in surface sediment samples from two selected rivers in Tianjin, Haihe River and Dagu Drainage River. A total of 16 surface sediment sites were selected along the both rivers. The frequency of detection of T-HCH and T-DDT in sediment samples both was up to 100%, which illustrated that the contamination of HCH and DDT was widespread in Haihe and Dagu Drainage Rivers. Results indicated that the concentrations of various pesticides in sediments from Haihe River were in the range of 3.30-75.96 ng/g dw for T-HCH and 1.57-211.57 ng/g dw for T-DDT. Compared with Haihe River, Dagu Drainage River was contaminated by HCHs and DDTs along the all locations and the values of T-HCH and T-DDT residues in sediments ranged from 2.30 to 124.61 ng/g dw and from 11.28 to 237.30 ng/g dw, respectively, The possible pollution sources were analyzed through monitoring results of organochlorine pesticides（OCPs） residues in sediments from the two rivers. The investigation also indicated that HCH was still used as pesticide in Tianjin partial area.

关键词： Haihe River Dagu Drainage River sediment OCPs DDT HCH

Quantile Regression under Local Misspecification

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 790-802页

作者： xiao-gang DUAN Qi-hua WANG School of Statistics Beijing Normal UniversityBeijing 100875Chin Academy of Mathematics and System Science Chinese Academy of SciencesBeijing 100190China

The frequentist model averaging(FMA)and the focus information criterion(FIC)under a local framework have been extensively studied in the likelihood and regression setting since the seminal work of Hjort and Claes kens in *** inconvenience,however,of the existing works is that they usually require the involved criterion function to be twice differentiable which thus prevents a direct application to the case of quantile regression(QR).This as well as some other intrinsic merits of QR motivate us to study the FIC and FMA in a locally misspecified linear QR ***,we derive in this paper the explicit asymptotic risk expression for a general submodel-based QR estimator of a focus *** based on this asymptotic result,we develop the FIC and FMA in the current *** theoretical development depends crucially on the convexity of the objective function,which makes possible to establish the asymptotics based on the existing convex stochastic process *** studies are presented to illustrate the finite sample performance of the proposed *** low birth weight data set is analyzed.

关键词： frequentist model averaging focus information criterion local framework quantile regression

Temperature dependence of Lüders strain and its correlation with martensitic transformation in a medium Mn transformation-induced plasticity steel

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Journal of Iron and Steel Research International 2017年第11期24卷 1073-1077页

作者： xiao-gang Wang Ming-xin Huang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College ot Mechanical and Vehicle EngmeermgHunan UniversityChangsha 410082HunanChina Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina

The Luders deformation behavior in a medium Mn transformation induced plasticity （TRIP） steel is investigated at different temperatures ranging from 25 to 300 ℃. It demonstrates that the Ltiders band appears at all testing temperatures but with varied Luders strains which do not change monoton ically with temperature. The martensitic transformation is simultaneously observed within the Ltiders band in varying degrees depending on the testing temperature. It is well verified that the martensitic transformation is not responsible for the formation of Luders band, and a reasonable explanation is given for the non-monotonic variation of Luders strain with increasing temperature.

关键词： Medium Mn steel TRIP effect Luders band Plastic instability Martensitic transformation

A compressive tracking based on time-space Kalman fusion model

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Science China(Information Sciences) 2016年第1期59卷 120-134页

作者： xiao YUN Zhongliang JING gang xiao Bo JIN Canlong ZHANG School of Aeronautics and Astronautics Shanghai Jiao Tong University School of Software Engineering East China Normal University School of Computer Science and Information Technology Guangxi Normal University

The compressive tracking(CT) method is a simple yet efficient algorithm which compresses the high-dimensional features into a low-dimensional space while preserving most of the salient information. This paper proposes a compressive time-space Kalman fusion tracking algorithm to extend the CT method to the case of multi-sensor fusion tracking. Existing fusion trackers deal with multi-sensor features individually and without time-space adaptability. Besides, significant information cumulated in the updating process has not been fully exploited, which calls for a necessity for temporal information extraction. Unlike previous algorithms,the proposed fusion model is completed in both space and time domains. Also, extended Kalman filter is introduced to formulate an updating method for fusion coefficient optimization. The accuracy and robustness of the proposed fusion tracking algorithm are demonstrated by several experimental results.

关键词： fusion tracking compressive tracking time-space Kalman fusion model extended Kalman filter visual tracking

Synthesis of Organofluorine Compounds with Acylsilanes

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Chinese Journal of Chemistry 2024年第8期42卷 887-902页

作者： Youyuan Guo gang Zhou xiao Shen The Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan University299 Bayi RoadWuhanHubei430072 China

Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material *** this review,we summarize the investigations on the synthesis of organofluorine compounds with *** the non-fluorinated acylsilanes,the in situ generation of difluoroenoxysilanes from the reactions of the acylsilanes with trifluoromethylation reagents is the major pathway,leading to the facile preparation of variousα,α-*** the fluoroalkylacylsilanes,apart from the in situ generation of difluoroenoxysilanes through anion Brook rearrangement,radical Brook rearrangement of the photoexcited acylsilanes and the selective control of reactivities of the biradicals pave the way for the synthesis of a variety of organofluorine *** general,most of these reactions gave racemic products,and the asymmetric synthesis of organofluorine compounds with acylsilanes is still rare,which would be a future.

关键词： Acylsilanes Organofluorine compounds Brook rearrangement Radical rearrangement β-Fluoride elimination Asymmetric catalysis Photocatalysis Defluoroalkylation