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Optimum weighting-coefficient-pair in inter-carrier interference self-cancellation scheme of OFDM system

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1676-1684页

作者： min-jian zhao Di ZHANG Bin CAI Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

As one of the most important components of the wideband wireless access technique, orthogonal frequency division multiplexing （OFDM） has a high usage rate of spectrum and combats inter-symbol interference （ISI） in multi-path fading channel. However, when there are frequency offsets during the signal transmission, the inter-carrier interference （ICI） is introduced, which significantly degrades the performance. The existing ICI self-cancellation schemes such as PCC-OFDM are not optimum to minimize the interference considering both noise and ICI. In this paper, a new metric named S1NR （signal-to-interference- and-noise ratio） is proposed. We discuss the optimization issue when a constant frequency offset exists and in time-varying channels. The optimum weighting-coefficient-pair （OWCP） is obtained, which maximizes SINR theoretically through the alternant iteration algorithm. Simulations show that the performance of OWCP-OFDM is better than that of PCC-OFDM, especially when the frequency offset is large. Although the ICI self-cancellation scheme suffers bandwidth inefficiency, from the simulation results we can also see that the performance of OWCP-OFDM is much better than that of the standard OFDM systems with the same bandwidth efficiency when a frequency offset exists. Moreover, since the redundant modulation provides the capability to suppress ICI as well as a receiving SNR gain, it can be considered as exchanging the bandwidth for SNR.

关键词： Orthogonal frequency division multiplexing (OFDM) Frequency offset Inter-carrier interference (ICI) Polynomial cancellation coding (PCC) Optimum weighting-coefficient-pair (OWCP)

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A cross-layer design approach on spectrum allocation and resource scheduling in cognitive PMP networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 435-444页

作者： Jie CHEN min-jian zhao Qiao ZHOU Shi-ju LI Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

We propose the spectrum allocation and resource scheduling algorithms in cognitive point to multipoint (PMP) networks with rapid changes of spectrum opportunities and present a media access control (MAC) protocol based on these algorithms. The objective of spectrum allocation is to make efficient use of the spectrum while maintaining the transceiver synchronization on frequency and time in the network. The objective of resource scheduling is to guarantee the quality of service (QoS) requirements of different kinds of connections and to minimize the total energy consumption in the network as well. By sensing only a small set of possible channels in each slot based on the state transition probability of each channel, our spectrum allocation algorithm achieves high spectrum efficiency in the network. The resource scheduling problem is divided into three sub problems and we derive optimal solutions to these problems by greedy algorithm and convex optimization. The simulation results show that our algorithm can make efficient use of the spectrum and the network resources at a cost of low computational complexity.

关键词： Cognitive point to multipoint (PMP) networks Markov process Cross-layer design Convex optimization

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Joint adaptive power allocation and interference suppression algorithms based on the MSER criterion for wireless sensor networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第10期15卷 917-928页

作者： Gui-jie WANG Yun-long CAI min-jian zhao Jie ZHONG Department of Information Science and Electronic Engineering Zhejiang University

In this study, a two-hop wireless sensor network with multiple relay nodes is considered where the amplify-and-forward(AF) scheme is employed. Two algorithms are presented to jointly consider interference suppression and power allocation(PA) based on the minimization of the symbol error rate(SER) criterion. A stochastic gradient(SG) algorithm is developed on the basis of the minimum-SER(MSER) criterion to jointly update the parameter vectors that allocate the power levels among the relay sensors subject to a total power constraint and the linear receiver. In addition, a conjugate gradient(CG) algorithm is developed on the basis of the SER criterion. A centralized algorithm is designed at the fusion center. Destination nodes transmit the quantized information of the PA vector to the relay nodes through a limited-feedback channel. The complexity and convergence analysis of the proposed algorithms are carried out. Simulation results show that the proposed two adaptive algorithms significantly outperform the other previously reported algorithms.

关键词： Cooperative communications Adaptive filtering Symbol error rate(SER) Interference suppression Power allocation

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Controlling structural topology of metal-organic frameworks with a desymmetric 4-connected ligand through the design of metal-containing nodes

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Chinese Chemical Letters 2016年第4期27卷 502-506页

作者： Bin Wang Hui Yang Ya-Bo Xie Yi-Bo Dou min-jian zhao jian-Rong Li Beijing Key Laboratory for Green Catalysis and Separation Department of Chemistry and Chemical Engineering College of Environmental and Energy Engineering Beijing University of Technology

Two new metal-organic frameworks（MOFs）,[Cu2（H_2O）_2（BCPIA）]（BUT-20）and（Me_2NH_2）[In（BCPIA）]（BUT-21）were designed and synthesized through the solvothermal reaction between a newly created desymmetric 4-connected ligand,5-（2,6-bis（4-carboxyphenyl）pyridin-4-yl）isophthalic acid（H_4BCPIA）and Cu（NO_3）2 2.5H_2O or In（NO_3）_3·5H_2O,respectively,and characterized by single-crystal and powder Xray diffraction,thermogravimetric analysis,infrared spectroscopy,and elemental *** two MOFs have three-dimensional structures,in which both the BCPIA 4 ligand and metal-containing entities,Cu_2（COO）_4（H_2O）_2 and In（COO）_4 act as 4-connected ***,different linkage configurations of the two metal-containing nodes,quadrilateral Cu_2_TD_2（COO）_4（H_2O）_2and tetrahedral In（COO）_4,lead to distinct structural networks of BUT-20 and 21,with Nbo and Unc topologies,respectively.

关键词： Metal-organic frameworks(MOFs) Design and synthesis Crystal structure Tuned topological network

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Mallet finger deformities treated by buried purse-string suture

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Chinese Journal of Traumatology 2011年第4期14卷 237-240页

作者： YAO jian-min zhao Feng-jing Department of Hand Surgery Hangzhou Plastic Sur-gery Hospital Hangzhou 310014

Objective： To investigate the efficacy of buried purse-string suture in the treatment of mallet finger deformities. Methods： From February 2009 to February 2010, 12 patients with closed non-fracture mallet fingers were treated by buried purse-string suture. The rupture tendons were sutured by purse-string suture with an atraumatic needle, and the knots were buried under subcutaneous tissue. External fixator was used at the extension position of the finger every night within three weeks after operation. Results： All patients were followed up for 6-12 months, mean 7 months. According to the Patel＇s evaluation criteria, 2 cases （17%） obtained excellent results, 7 good （58%）, 2 fair （17%） and 1 poor （8%）. The overall rate of the cases with excellent and good outcomes was 75%. Conclusion： Buried purse-string suture is an easy and effective way to treat mallet finger deformities, with no serious postoperative complications or no need for reoperation.

关键词： Tendon injuries Finger injuries Suture techniques External fixator

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Analysis of risk factors of surgical site infections in breast cancer

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Chinese Medical Journal 2010年第5期123卷 559-562页

作者： GAO Yang-xu XU Ling YE Jing-ming WANG Dong-min zhao jian-xin ZHANG Lan-bo DUAN Xue-ning LIU Yin-hua Center of Breast Disease Peking University First Hospital Beijing 100034 China

Background Adjuvant chemotherapy has become an important component of standard therapy for breast cancer. However, until now, there have been few reports on the surgical site infections （SSI） after breast cancer surgery, specially after adjuvent chemotherapy. To study the risk factors of SSI of breast cancer, we analyzed patients diagnosed with breast cancer and treated with surgery. Methods Fifty-five patients diagnosed with breast cancer and received breast conserving or modified radical operations in our hospital during January 2008 to March 2008 were selected. Factors （patients＇ age, body mass index （BMI）, diabetes mellitus, no or administered adjuvant chemotherapy, with or without onset of myelosuppression and the degree, surgical approaches, duration of operation, postoperative drainage duration and total drainage volume） associated with SSI were retrospectively reviewed and statistically analyzed by single factor analysis. Results Five patients suffered SSI （5/55, 9.1%）; nineteen receiving adjuvant chemotherapy experienced Grade III＋ myelosuppression, among which 4 had SSI; only 1 out of the remaining 36 patients without adjuvant chemotherapy had SSI. The difference between the two groups was significant （P=-0.043）. The incidence of SSI in patients with postoperative drainage tube indwelling longer than 10 days was 5/21, whereas no SSI occurred in that less than 10 days （P=0.009）. In our study, there was no significient difference in other associated factors. Conclusions Concurrent Grade III＋ myelosuppression after adjuvant chemotherapy is an important risk factor of SSI in breast cancer and needs further study. No SSI was detected with indwelling time of post operative drainage less than 10 days.

关键词： breast cancer adjuvant treatment surgical site infection

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一种用于超高频RFID读写器的载波泄漏抑制改进算法

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科学技术与工程 2016年第36期16卷 213-216,222页

作者：高格庄健敏张钊锋中国科学院上海高等研究院上海201210 中国科学院大学北京100049

在超高频RFID系统中,评价系统性能的两个关键指标是最大读写距离和识别率。当读写器采用基于单天线的环形器或耦合器隔离方案,由于接收信号和发送信号同频率,发射通路的载波信号会泄漏到接收通路,降低接收机的灵敏度,从而大大降低读写... 详细信息

在超高频RFID系统中,评价系统性能的两个关键指标是最大读写距离和识别率。当读写器采用基于单天线的环形器或耦合器隔离方案,由于接收信号和发送信号同频率,发射通路的载波信号会泄漏到接收通路,降低接收机的灵敏度,从而大大降低读写器的性能,严重影响RFID系统的应用。为了解决环形器或耦合器隔离度不高导致的载波信号泄漏问题,常用解决方法是在读写器中增加一个载波泄漏抑制模块,提高收发通路之间的隔离度。本文在原有梯度搜索范围上进行了优化,将IQ复平面的相位多等份分割,以此构造不同相位试探信号快速定位抑制信号相位搜索范围,提供了一种高效载波泄漏抑制信号的产生方式;并且通过与其他常用的载波抑制方法的对比分析,证明了改进算法的高效性。

关键词：射频识别读写器载波泄漏

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Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2982-2997页

作者： Hongli Li jianhua Huang Di zhao Lemei Zhu Zheyu Zhang min Yi Weijun Peng Department of Integrated Traditional Chinese&Western Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina National Clinical Research Center for Metabolic Diseases ChangshaHunan ProvinceChina Hunan Academy of Chinese Medicine ChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina

Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut *** aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease *** do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of ***-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 ***,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 *** findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies.

关键词： Alzheimer’s disease APP/PS1 mice brain-kidney axis gut microbiota heart-brain axis liver-brain axis lung-brain axis microbiota-gut-brain axis peripheral organ metabolism spleen-brain axis

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Construction of Ni single-atom coordinated with doped N and S elements for mild hydrogenation of methyl acrylate to methyl propionate

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Nano Research 2025年第1期18卷 217-224页

作者： Taolue Sun Chen jian Gang Wang Hui zhao Guoliang Zhang Zengxi Li Chunshan Li State Key Laboratory of Mesoscience and Engineering CAS Key Laboratory of Green Process and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Huizhou Institute of Green Energy and Advanced Materials Huizhou 516081China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516081China

Although the nickel-based catalyst is able toexhibit comparative catalytic activity to noble metal formethyl acrylate hydrogenation,it requires strict reactioncondition,which can be improved by regulation ofcoordination *** this study,we constructed akind of Ni single-atom coordinated with N and S(Ni-NSC)through the pyrolysis of organic Ni-based precursors at600℃.The existence and fine structure of Ni single-atom were confirmed by the spherical electron microscopicobservation in combination with the X-ray absorption spectroscopy(XAS)*** addition,the catalytichydrogenation assessment suggested that the as-prepared Ni-NSC catalyst exhibited higher activity and stability than theNi/NSC supported catalyst prepared by incipient wetness impregnation *** remarkable catalytic activity was dueto the high dispersion and density of Ni single-atom and weak adsorption energy of intermediates on these Ni sites.

关键词： methyl acrylate mild hydrogenation Ni single-atom coordination environment adsorption energy

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Unlocking the stable interface in aqueous zinc-ion battery with multifunctional xylose-based electrolyte additives

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Journal of Energy Chemistry 2025年第1期100卷 770-778页

作者： Xiaoqin Li jian Xiang Lu Qiu Xiaohan Chen Yinkun zhao Yujue Wang Qu Yue Taotao Gao Wenlong Liu Dan Xiao zhaoyu Jin Panpan Li Institute for Advanced Study Chengdu University School of Mechanical Engineering Chengdu University College of Food and Biological Engineering Chengdu University Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China College of Materials Science and Engineering Sichuan University

The growth of dendrites and the side reactions occurring at the Zn anode pose significant challenges to the commercialization of aqueous Zn-ion batteries（AZIBs）. These challenges arise from the inherent conflict between mass transfer and electrochemical kinetics. In this study, we propose the use of a multifunctional electrolyte additive based on the xylose（Xylo） molecule to address these issues by modulating the solvation structure and electrode/electrolyte interface, thereby stabilizing the Zn anode. The introduction of the additive alters the solvation structure, creating steric hindrance that impedes charge transfer and then reduces electrochemical kinetics. Furthermore, in-situ analyses demonstrate that the reconstructed electrode/electrolyte interface facilitates stable and rapid Zn2+ion migration and suppresses corrosion and hydrogen evolution reactions. As a result, symmetric cells incorporating the Xylo additive exhibit significantly enhanced reversibility during the Zn plating/stripping process, with an impressively long lifespan of up to 1986 h, compared to cells using pure ZnSO4electrolyte. When combined with a polyaniline cathode, the full cells demonstrate improved capacity and long-term cyclic stability. This work offers an effective direction for improving the stability of Zn anode via electrolyte design, as well as highperformance AZIBs.

关键词： Solvation

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