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Sub-channel interference cancellation in SVD-based MIMO system

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 34-37页

作者： WU Ping li li-hua zhang Ping Beijing University of Posts and Telecommunications Beijing 100876 China

For singular value decomposition （SVD）-based multiple input multiple output （MIMO） systems, implicit channel state information （CSI） incurs interferences amongst sub-channels if the CSI at the transmitter is not explicit. An improved SVD-based MIMO which can fully cancel the inter sub-channel interferences by reconstructing the transmitter- receiver system matrix on interferences analysis is provided. Simulation results indicate that the proposed algorithm outperforms the traditional SVD-based MIMO in a large degree.

关键词： MIMO systems SVD interference cancellation (IC) CSI feedback

Sensitivity of key factors and uncertainties in health risk assessment of benzene pollutant

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Journal of Environmental Sciences 2007年第10期19卷 1272-1280页

作者： liU Zhi-quan zhang Ying-hua li Guang-he zhang Xu Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

Predicting long-term potential human health risks from contaminants in the multimedia environment requires the use of models. However, there is uncertainty associated with these predictions of many parameters which can be represented by ranges or probability distributions rather than single value. Based on a case study with information from an actual site contaminated with benzene, this study describes the application of MMSOILS model to predict health risk and distributions of those predictions generated using Monte Carlo techniques. A sensitivity analysis was performed to evaluate which of the random variables are most important in producing the predicted distributions of health risks. The sensitivity analysis shows that the predicted distributions can be accurately reproduced using a small subset of the random variables. The practical implication of this analysis is the ability to distinguish between important versus unimportant random variables in terms of their sensitivity to selected endpoints. This directly translates into a reduction in data collection and modeling effort. It was demonstrated that how correlation coefficient could be used to evaluate contributions to overall uncertainty from each parameter. The integrated uncertainty analysis shows that although drinking groundwater risk is similar with inhalation air risk, uncertainties of total risk come dominantly from drinking groundwater route. Most percent of the variance of total risk comes from four random variables.

关键词： Monte Carlo sensitivity uncertainty MMSOILS models risk assessment

Molecularly imprinted macroporous monolithic materials for protein recognition

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Chinese Chemical Letters 2011年第11期22卷 1351-1354页

作者： Qi liang Deng Yan li li li hua zhang Yu Kui zhang Department of Science Tianjin University of Science and Technology Tianjin 300222 China National Chromatograp＇hic R. ＆ A. Center Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

Synthetic materials that can specifically recognize proteins will find wide application in many *** this report,bovine serum albumin was chosen as the template *** and N,N＇-methylenebisacrylamide were employed as the functional and cross-linker monomers,*** imprinted macroporous monolithic materials that can preferentially bind the template protein in an aqueous environment were prepared by combination of molecular imprinting technique and freezing/thawing preparation *** resulted imprinted macroporous monolithic columns were evaluated by utilizing as stationary phase in high performance liquid chromatography and solid-phase extraction *** experimental results indicated that the imprinted macroporous monolithic column exhibited good recognition for template protein,as compared with the control protein（hemoglobin）,whereas the non-imprinted polymer（prepared under the same conditions except without addition template protein） had no selective properties.

关键词： Molecularly imprinted polymers Protein Monolithic column High performance liquid chromatography

Dynamical-corrected nonadiabatic geometric quantum computation

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Frontiers of physics 2023年第6期18卷 263-273页

作者： Cheng-Yun Ding li Chen li-hua zhang Zheng-Yuan Xue School of Mathematics and Physics Anqing Normal UniversityAnqing 246133China Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education) and School of PhysicsSouth China Normal UniversityGuangzhou 510006China School of Electronic Engineering and Intelligent Manufacturing Anqing Normal UniversityAnqing 246133China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials Guangdong-Hong Kong Joint Laboratory of Quantum Matterand Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China

Recently,nonadiabatic geometric quantum computation has been received great attentions,due to its fast operation and intrinsic error ***,compared with the corresponding dynamical gates,the robustness of implemented nonadiabatic geometric gates based on the conventional single-loop geometric scheme still has the same order of magnitude due to the requirement of strict multi-segment geometric controls,and the inherent geometric fault-tolerance characteristic is not fully ***,we present an effective geometric scheme combined with a general dynamical-corrected technique,with which the super-robust nonadiabatic geometric quantum gates can be constructed over the conventional single-loop geometric and two-loop composite-pulse geometric strategies,in terms of resisting the systematic error,i.e.,σ_(x)*** addition,combined with the decoherence-free subspace(DFS)coding,the resulting geometric gates can also effectively suppress theσ_(z)error caused by the collective ***,our protocol is a general one with simple experimental setups,which can be potentially implemented in different quantum systems,such as Rydberg atoms,trapped ions and superconducting *** results indicate that our scheme represents a promising way to explore large-scale fault-tolerant quantum computation.

关键词： geometric phases dynamical-corrected gates fault-tolerant quantum computation

Beta-blockers and 1-year clinical outcomes in hospitalized heart failure patients with atrial fibrillation

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Journal of Geriatric Cardiology 2021年第9期18卷 728-738页

作者： Fu-Wei XING li-hua zhang Hai-Bo zhang Xue-Ke BAI Dan-li HU Xin ZHENG Jing li National Clinical Research Center for Cardiovascular Diseases NHC Key Laboratory of Clinical Research for Cardiovascular MedicationsState Key Laboratory of Cardiovascular DiseaseFuwai HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeNational Center for Cardiovascular DiseasesBeijingChina

OBJECTIVE To assess the association between beta-blockers and 1-year clinical outcomes in heart failure(HF)patients with atrial fibrillation(AF),and further explore this association that differs by left ventricular ejection fraction(LVEF)*** We enrolled hospitalized HF patients with AF from China Patient-centered Evaluative Assessment of Cardiac Events Prospective Heart Failure *** proportional hazard regression models were employed to calculate hazard ratio of *** primary outcome was all-cause *** Among 1762 HF patients with AF(756 women[41.4%]),1041(56%)received beta-blockers at discharge and 1272(72.2%)had an LVEF>40%.During one year follow up,all-cause death occurred in 305(17.3%),cardiovascular death occurred in203 patients(11.5%),and rehospitalizations for HF occurred in 622 patients(35.2%).After adjusting for demographic characteristics,social economic status,smoking status,medical history,anthropometric characteristics,and medications used at discharge,the use of beta-blockers at discharge was not associated with all-cause death[hazard ratio(HR):0.86;95%Confidence Interval(CI):0.65-1.12;P=0.256],cardiovascular death(HR:0.76,95%CI:0.52-1.11;P=0.160),or the composite outcome of all-cause death and HF rehospitalization(HR:0.97,95%CI:0.82-1.14;P=0.687)in the entire *** were no significant interactions between use of beta-blockers at discharge and LVEF with respect to all-cause death,cardiovascular death,or composite *** the adjusted models,the use of beta-blockers at discharge was not associated with all-cause death,cardiovascular death,or composite outcome across the different levels of LVEF:reduced(linical outcomes,regardless of LVEF.

关键词： Beta-blockers and 1-year clinical outcomes in hospitalized heart failure patients with atrial fibrillation

Thioxanthene-9-thione Mediated MMA Polymerization

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Chinese Journal of Polymer Science 2018年第7期36卷 805-810页

作者： Xu Yan Guan Wang li-hua zhang li Wang Xiao-Fei liu Wan-Tai Yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical and Technology Beijing Laboratory of Biomedical Materials Polymer Materials Beijing University of Chemical and Technology

In the ＂cycloketyl radical mediated living polymerization＂（CMP） process, a cycloketyl compound, [9,9＇]bixanthenyl-9,9＇ diol （BIXAN） was ultilized as initiator and mediator. The cycloketyl （CK） radical was used as the dormant radical to achieve the increase of molecular weight. Herein, a series of cycloketyl thioketones were synthesised by Lawesson＇s reagent by one step reaction with high yeild, and we found that, when a special cyeloketyl thioketone compound, thioxanthene-9-thione （TXT）, was added to a routine radical polymerization system, TXT could capture chain radical, and simultaneously formed an radical analogous to CK radical in structure, which could trigger the growth of polymer chains. This simple system was efficient to initiate the polymerization of methyl methacrylate （MMA） and in all cases the molecular weights increased with the increase of conversions. By the end-group analysis with 1H-NMR and MALDI-TOF MS, it was confirmed that the P-STXT radical was used to control the polymerization. The re-initiating reactions were achieved when PMMA was used as the macro-initiator.

关键词： Thioxanthene-9-thione Lawesson's reagent Methyl methacrylate Radical polymerization

Synthesis of indium tin oxide nano-polycrystalline powders by ultrasonic spray pyrolysis

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Rare Metals 2022年第10期41卷 3579-3584页

作者： li-hua zhang Sheng-Hui Guo Chao-Jin Zhou Jin-Hui Peng Shao-hua Ju Jian-Bo Lan Yunnan Provincial Key Laboratory of Intensification Metallurgy Kunming650093China Key Laboratory of Unconventional Metallurgy Ministry of EducationKunming650093China National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology Kunming650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming650093China

Indium tin oxide(ITO) nano-polycrystalline powders were prepared by ultrasonic spray pyrolysis(USP) method using a precursor solution of indium and tin chlorides in a simple one-step process without any post-heat treatment,additives and other complex *** morphology and crystal structure of ITO powders were studied by thermogravimetric and differential thermal analysis(TG-DTA),X-ray diffraction(XRD),energy-dispersive spectrometer(EDS),scanning electron microscopy(SEM),laser particle size analyzer(LPSA),transmission electron microscope(TEM),high-resolution transmission electron microscopy(HRTEM) and selected area electron diffraction(SAED),*** results indicate that pure cubic ITO solid solution could be obtained at and above the pyrolysis temperature of 600℃.Through adjusting the size of atomized precursor droplets,the particles with regular spherical shape and smooth surface are also *** spherical particles have a narrow size distribution with a dominant diameter size in the range of 0.52-1.28 μm,and the average value is 1.01 μ*** clear lattice fringes in HRTEM image confirm a polycrystalline structure of ITO particles with the growth direction along(222) direction.

关键词： Indium tin oxide Ultrasonic spray pyrolysis Nano-polycrystalline powder Chloride precursor

Smith Prediction Monitor AGC System Based on Fuzzy Self-Tuning PID Control

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Journal of Iron and Steel Research International 2010年第2期17卷 22-26页

作者： SUN Jie zhang Dian-hua li Xu zhang Jin DU De-shun State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

In accordance with the feature of pure delay in monitor AGC system for cold rolling mill, a new fuzzy selftuning PID Smith prediction controller is developed. The position control model is deduced based on a single stand cold rolling mill, and the fuzzy controller for monitor AGC system is designed. The analysis of dynamic performance for traditional PID Smith prediction controller and fuzzy self-tuning PID Smith prediction controller is done by MAT- LAB toolbox. The simulation results show that fuzzy self-tuning PID Smith controller has stronger robustness, faster response and higher static accuracy than traditional PID Smith controller.

关键词： monitor AGC fuzzy self-tuning PID control Smith predictor position control

The Quantitative Evaluation of Output Efficiency in Different Cropping Patterns

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Agricultural Sciences in China 2006年第2期5卷 98-102页

作者： liU Yu-hua zhang li-feng College of Agronomy Agricultural University of Hebei Baoding 071001 P.R.China

Quantitative indexes such as land equivalent ratio, yield equivalent and value of output equivalent were used to evaluate output efficiencies of different cropping patterns, i.e., sequential cropping, intercrops and crop rotation. Compared to single cropping, land use efficiencies under sequential cropping, intercrops and crop rotation were raised by 62, 38 and 21%, respectively. The unit area yield under sequential cropping, intercrops and crop rotation were raised by 63, 29 and 16%, respectively. The unit area value was also enhanced under sequential cropping and intercrops, 76 and 35% higher than that under single cropping. The paper provides a useful tool for comparing farm output efficiency and build up a theoretical basis for further research on output efficiency of various cropping patterns in the future.

关键词： sequential cropping intercrops rotation cropping patterns quantitative evaluation