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An Enhanced Spectrum Resource Allocation Algorithm in Hetnets

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China Communications 2015年第10期12卷 182-192页

作者： zhao linjing zhao Huaying HUO Guangrui Broadband Wireless Communications Laboratory State Key Laboratory of Integrated Service NetworksXidian University

Efficient spectrum resource allocation in wireless heterogeneous networks is important for improving the system throughput and guaranteeing the user's Quality-of-Service(QoS).In this paper,we propose an enhanced algorithm for spectrum resource allocation in heterogeneous ***,the bandwidth of each user is determined by the user's rate demand and the channel ***,graph theory is enhanced and used to improve the spectrum ***,spectrum resource is dynamically split between macrocell and femtocells with the changes of users' *** simulation results show that the proposed algorithm improves the system throughput significantly and also guarantees the fairness for the users.

关键词： resource management heterogeneous networks graph theory throughput fairness

Adaptive joint bandwidth and power allocation in heterogeneous wireless access environment

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Science China(Information Sciences) 2014年第6期57卷 89-102页

作者： YAN JiLei LI JianDong zhao linjing Broadband Wireless Communications Laboratory Information Science InstituteState Key Laboratory of ISNXidian University

Joint bandwidth and power allocation for a multi-radio access(MRA)system in a heterogeneous wireless access environment is *** both the number of users being served by the system and the wireless channel state are time-varying,the optimal resource allocation is no longer a static optimum and will change with the varying network ***,distributed resource allocation algorithms that require iterative updating and signaling interactions cannot converge in negligible ***,it is unrealistic to assume that the active user number and the wireless channel state remain unchanged during the *** this paper,we propose an adaptive joint bandwidth and power allocation algorithm based on a novel iteration stepsize selection method,which can adapt to the varying network state and accelerate the convergence rate.A distributed solution is also designed for the adaptive joint resource allocation *** results show that the proposed algorithm can not only track the varying optimal resource allocation result much more quickly than a traditional algorithm with fixed iteration stepsize,but can also reduce the data transmission time for users and increase the system throughput.

关键词： heterogeneous wireless networks multi-radio access system resource allocation network utility maximization adaptive stepsize

Dix-Type Multi-Component Scholte Wave Dispersion Inversion without Initial Model

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Journal of Earth Science 2024年第4期35卷 1393-1396页

作者： linjing zhao Xiangchun Wang Xiaobo Liu School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China Key Laboratory of Intraplate Volcanoes and Earthquakes Ministry of EducationChina University of GeosciencesBeijing 100083China School of Ocean Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Polar Geology and Marine Mineral Resources Ministry of EducationChina University of GeosciencesBeijing 100083China

0 INTRODUCTION Scholte wave dispersion curves contain rich information regarding seafloor media and have therefore attracted increasing attention(Wang et al.,2022;Dong et al.,2021;Du et al.,2020).Ocean bottom seismometer(OBS)data are widely used in the study of seafloor medium information(Wang et al.,2024),and contain rich surface wave information.

关键词： seafloor wave Inversion

Interference management for rate-constrained moving relay node in a heterogeneous network

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Science China(Information Sciences) 2014年第10期57卷 34-45页

作者： HUANG Sheng LI JianDong zhao linjing HUANG JinJing Broadband Wireless Communications Laboratory Information Science InstituteState Key Laboratory of ISN Xidian University

Cooperative communication via a moving relay node(MRN) helps resolve both the poor quality of service(QoS) and limited battery-capacity problems of cell-edge vehicle user equipment(VUE). This paper investigates the performance of MRNs in a heterogeneous network(HetNet). MRNs as well as other small cells are expected to coexist in a complex manner. In such a HetNet, the inter-cell interference may degrade the expected improvement of MRNs, especially at the cell-edge. In this paper, we investigate the impact of intercell interference on the performance of MRNs. To alleviate this impact, we first formulated a general optimization problem for which it is intractable to find a global optimal solution. To have a practical solution with low computational complexity, we used a practical interference management algorithm that aimed to ensure that every MRN achieved its required minimum-rate while maximizing total network throughput. In the simulations, the proposed algorithm was observed to improve both the QoS and fairness of MRNs. Numerical results demonstrate that the proposed algorithm can offer an efficient trade-off between the performance of both the victim MRNs and aggressing femtocells.

关键词： moving relay node minimum-rate constraint heterogeneous network inter-cell interference sub-channel allocation interference mitigation

Uplink resource allocation in OFDMA system using distributed antennas

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Science China(Information Sciences) 2013年第12期56卷 297-302页

作者： YAN JiLei LI JianDong zhao linjing SHI Hua Broadband Wireless Communications Laboratory Information Science Institute State Key Laboratory of Integrated Services Networks Xidian University

In this article,we investigate uplink resource allocation in orthogonal frequency division multiple access(OFDMA)systems that use distributed *** multiple distributed receiving antennas motivate us to exploit the spatial diversity to maximize the achievable rate of the *** constraints on the subcarrier allocation and the power limit of each user equipment(UE),a mixed-integer optimization problem is *** frst propose a centralized greedy algorithm to fnd the maximum achievable rate of the *** a heuristic algorithm is proposed that can be implemented in a distributed *** results show that the heuristic algorithm can approximately achieve the maximum achievable rate of the system and result in signifcant system performance improvement over the approach assigning one user to each subcarrier.

关键词： uplink OFDMA system distributed antennas subcarrier assignment power allocation heuristic algorithm

Optimal training sequences for MIMO systems under correlated fading

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Journal of Systems Engineering and Electronics 2008年第1期19卷 33-38页

作者： Pang Jiyong Li Jiandong Lu Zhuo zhao linjing Chen Liang Broadband Wireless Communications Lab Information Science Inst. State Key Lab of Integrated Service Networks Xidian Univ. Xi'an 710071 P. R. China

The optimal design of training sequences for channel estimation in multiple-input multiple-output （MIMO） systems under spatially correlated fading is considered. The channel is assumed to be a block-fading model with spatial correlation known at both the transmitter and the receiver. To minimize the channel estimation error, optimal training sequences are designed to exploit full information of the spatial correlation under the criterion of minimum mean square error （MMSE）. It is investigated that the spatial correlation is helpful to decrease the estimation error and the proposed training sequences have good performance via simulations.

关键词： MIMO channel estimation training sequences spatial correlation minimum mean square error

ERGODIC CAPACITY FORMULA OF MIMO-OFDM SYSTEMS UNDER CORRELATED FREQUENCY SELECTIVE RAYLEIGH FADING CHANNELS

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Journal of Electronics(China) 2007年第5期24卷 588-592页

作者： Pang Jiyong Li Jiandong zhao linjing Broadband Wireless Communications Lab Information Science InstituteState Key Lab of Integrated Service Networks Xidian University Xi＇an 710071 China

An explicit formula for the ergodic capacity of Orthogonal Frequency Division Multiplexing (OFDM)-based Multiple-Input Multiple-Output (MIMO) systems under correlated frequency selective Rayleigh channels is derived,by simplifying the channel response matrix in frequency domain into the so-called Kronecker model composed of three kinds of correlations,*** tap gain correlation and spatial fading correlations at both transmitter and *** derived formula is very simple and convenient for one to estimate the effects of all three kinds of correlations on MIMO-OFDM *** taps are independent,there is a very simple expression for the ergodic *** case of tap correlation,the capacity formula could be further given in an integral *** validity of the new formula is verified and the effects of correlations,delay spread as well as the number of subcarriers on the ergodic capacity are evaluated via Monte Carlo simulations.

关键词： Multiple-Input Multiple-Output (MIMO) Orthogonal Frequency Division Multiplexing(OFDM) Kronecker product Channel correlation Ergodic capacity

Parameter estimation for MIMO system based on MUSIC and ML methods

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Frontiers of Electrical and Electronic Engineering in China 2009年第2期4卷 161-165页

作者： Wei DONG Jiandong LI Zhuo LU linjing zhao Information Science Institute State Key Laboratory of Integrated Service NetworksXidian UniversityXi’an 710071China

The frequency offset and channel gain estimation problem for multiple-input multiple-output(MIMO)systems in the case of flat-fading channels is *** on the multiple signal classification(MUSIC)and the maximum likelihood(ML)methods,a new joint estimation algorithm of frequency offsets and channel gains is *** new algorithm has three steps.A subset of frequency offsets is first estimated with the MUSIC *** frequency offsets in the subset are then identified with the ML ***,channel gains are calculated with the ML *** algorithm is a one-dimensional search scheme and therefore greatly decreases the complexity of joint ML estimation,which is essentially a multi-dimensional search scheme.

关键词： multiple-input multiple-output(MIMO) multiple signal classification(MUSIC) frequency offsets channel estimation maximum likelihood(ML)estimation

Degradable nanocatalyst enables antitumor/antibacterial therapy and promotion of wound healing for diabetes via self-enhanced cascading reaction

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Chinese Chemical Letters 2023年第7期34卷 155-161页

作者： Xiang Wang Cheng Ding Ziwen Zhang Chunlin Li Dongmiao Cao linjing zhao Guoying Deng Yu Luo Chunping Yuan Jie Lu Xijian Liu School of Chemistry and Chemical Engineering Shanghai Engineering Technology Research Center for Pharmaceutical Intelligent EquipmentShanghai Frontiers Science Research Center for Druggability of Cardiovascular Noncoding RNAInstitute for Frontier Medical TechnologyShanghai University of Engineering ScienceShanghai201620China Affiliated Sixth People's Hospital Shanghai JiaoTong UniversityShanghai 200233China Trauma Center Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghai 201620China

Diabetic patients often have problems such as residual tumor and wound infection after tumor resection,causing severe clinical *** is urgent to develop effective therapies to reach oncotherapy/antiinfection/promotion of wound healing combined ***,we propose CS/MnO_(2)-GO_x (CMGO_x)nanocatalysts for the specific catalytic generation of ~·OH to inhibit tumors and bacteria in a hyperglycemic *** good biocompatible chitosan (CS),as a carrier for the catalyst,exhibits excellent antibacterial effect as well as promotes wound *** oxidase (GO_x) is loaded on the surface of CS nanoparticles to generate H_(2)O_(2) and gluconic acid by consuming glucose (starvation therapy,ST) and O_(2).The MnO_(2) depletes glutathione (GSH) to produce Mn^(2+),amplifying oxidative stress and further promoting the activity of Mn^(2+)-mediated Fenton-like reaction to produce~·OH (chemodynamic therapy,CDT)in weak acidic ***,the produced gluconic acid lowers the p H of the environment,enhancing chemodynamic therapy (ECDT).The tumor cells and bacteria are efficiently eliminated by the synergistic effect of ST and *** MnO_(2) nanoparticles at neutral environment decomposes H_(2)O_(2) into O_(2),which cooperate with CS to promote *** self-enhanced cascade reaction of CMGO_x in situ exhibits excellent effects of antitumor/antibacterial therapy and promotion of wound healing,offering a promising integrated treatment for diabetic patients after tumor surgical resection.

关键词： Self-cascade reaction Starvation therapy Chemodynamic therapy Antitumor Antibacterial Wound healing