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Improving amplify-and-forward relay selection algorithm based on partial relay link

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 56-61页

作者： wang fei-fei liu yuan-an LIN Xiao-feng xie gang Key Labomty of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

This article addresses the design problem of selecting an appropriate relay in amplify-and-forward （AF） cooperative diversity systems. In this regard, this article focuses on relay selection based on partial channel knowledge only across the source and relay links. In particular, the two fundamental questions will be answered, that is, whether to cooperate and whom to cooperate with. Through answering these two questions, an improved relay selection strategy based on partial relay link, which emphasizes that cooperation happens when necessary, is proposed to aim at maximizing the average mutual information. Then a joint optimization, in terms of power allocation and relay selection, is employed to guarantee a robust performance for relay selection based on partial relay link. Optimum power is allocated between the source and the selected relay to maximize the output signal-to-noise （SNR） at the destination. simulation results turn out that the improved scheme can achieve better performance than previous work and the robust performance can be guaranteed by employing joint optimization.

关键词： cooperative diversity amplify-and-forward relay relay selection average mutual information

Multi-Parameter Influence Analysis of Interaction Between Internal Solitary Wave and Fixed Submerged Body

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China Ocean Engineering 2023年第6期37卷 934-947页

作者： liu Shuang HE Guang-hua zhang Zhi-gang HU Chang-hong zhang Cheng wang Zheng-ke xie Hong-fei School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Shandong Institute of Shipbuilding Technology Weihai 264209China School of Ocean Engineering Harbin Institute of TechnologyWeihaiWeihai 264209China Research Institute for Applied Mechanics Kyushu UniversityFukuoka 816-0811Japan

To obtain the interaction characteristics between Internal solitary waves(ISWs)and submerged bodies,a three-dimensional numerical model for simulating ISWs was established in the present study based on the ranS *** velocity entrance method was adopted to generate the ***,the reliability of this numerical model was validated by comparing it with theoretical and literature ***,the influence of environmental and navigation parameters on interactions between ISWs and a fixed SUBOFF-submerged body was *** to research,the hydrodynamic performance of the submerged body has been significantly impacted by the ISWs when the body is nearing the central region of the ***,the pitching moment(y')will predominate when the body encounters the ISWs at a certain angle between 0°and 180°,and the lateral force is larger than the horizontal ***,the magnitude of the force acting on the body is mostly affected by the wave *** variation of the vertical force is the main way that ISWs affect the hydrodynamic performance of the *** investigations and findings discussed above can serve as a guide to forecast how ISWs will interact with submerged bodies.

关键词： CFD internal solitary waves submerged body multi-parameters influence hydrodynamics

Enhanced unipolar electrical fatigue resistance and related mechanism in grain-oriented Pb(Mg_(1/3)Nb_(2/3))O_(3)-Pb(Zr,Ti)O_(3)piezoceramics

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Journal of Materials Science & Technology 2023年第14期145卷 40-47页

作者： Linjing liu Bin yang Rui Lv Qiangwei Kou Shuai yang Hang xie yuan Sun Yunfei Chang Shan-Tao zhang fei Li Functional Materials and Acousto-Optic Instruments Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Electronic Materials Research Laboratory(Key Lab of Education Ministry) State Key Laboratory for Mechanical Behavior of Materials and School of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China National Laboratory of Solid State Microstructures and College of Engineering and Applied Science Nanjing UniversityNanjing 210093China

Piezoceramics with high and fatigue-resisted piezoelectric properties are strongly desired for actuator *** this work,textured Pb(Mg_(1/3)Nb_(2/3))O_(3)-Pb(Zr,Ti)O_(3)ceramics with Lotgering factor F_(001)∼98%were fabricated by templated grain growth ***[001]c-grain orientation(f∼90%and r∼0.22)of the textured ceramics effectively produced about 230%enhanced piezoelectric coefficient d_(33)^(∗)(i.e.,S_(max)/E_(max))and substantially improved unipolar electrical fatigue *** polarization P max and d_(33)^(∗)of the textured ceramics were nearly maintained up to 106 unipolar cycles,while 19%and 14%degradations were respectively observed from randomly oriented ***,normal-ized d_(33)^(∗)of the textured ceramics shows better unipolar fatigue resistance than those of piezoceramics reported *** lower bipolar strain asymmetryγs(∼4%)was observed from the textured samples fatigued after 106 unipolar cycles as compared toγs∼23%for randomly oriented *** charged defect accumulation model described the serious fatigue deteriorations in randomly ori-ented ceramics,the current work revealed that substantially enhanced unipolar fatigue resistance of the textured ceramics is mainly associated with the inherent fatigue anisotropy,weakened local bias fields owing to both enhanced domain mobility and lower defect density near grain boundaries/interfaces,and increased intrinsic contribution due to more tetragonal *** superior characteristics suggest the great potential of textured ceramics for high-performance and robust actuator applications.

关键词： Ceramics Grain orientation Piezoelectric strain Unipolar fatigue Defect accumulation

Evaluation of Essential and Toxic Element Concentrations in Buckwheat by Experimental and Chemometric Approaches

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Journal of Integrative Agriculture 2014年第8期13卷 1691-1698页

作者： PENG Lian-xin HUANG Yan-fei liu yuan zhang Zhi-feng LU Lu-yang ZHAO gang College of Biotechnology Industry Chengdu University Institute of Ethnic Medicine Southwest University for Nationalities Key Laboratory of Traditional Chinese Medicine Resource and Compound Prescription Ministry of Education/Hubei University of Chinese Medicine

The essential and toxic element concentrations in buckwheat were analyzed by inductively coupled plasma optical emission spectrometer（ICP-OES）. The concentration data were subjected to common chemometrics analyses, including correlation analysis（CA）, principal component analysis（PCA） and hierarchical cluster analysis（HCA）, to gain better understanding of the differences among the tested samples. Our results indicated that the essential and toxic element concentrations were not different between Fagopyrum tataricum（L.） Gaertn and F. esculentum Moench. The element concentrations varied among buckwheat samples from different sources. Commercial tartary buckwheat tea contained several essential elements, thus, could be used as the source of essential elements. The detection of toxic heavy metals in commercial tartary buckwheat tea suggested that safety issue of such buckwheat products should be seriously concerned. Our results also revealed that the place of origin and the processing protocol of tartary buckwheat affected the element concentrations of the commercial form. The implications to the quality control and safety evaluation of buckwheat were extensively discussed.

关键词： buckwheat ICP-OES trace element toxic element chemometrics

Plant water use strategies in the Shapotou artificial sand-fixed vegetation of the southeastern margin of the Tengger Desert, northwestern China

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Journal of Mountain Science 2019年第4期16卷 898-908页

作者： ZHAO Liang-ju wang Xiao-gang zhang Yu-cui xie Cong liu Quan-yu MENG fei Key Laboratory of Earth Surface System and Environmental Carrying Capacity College of Urban and Environmental Sciences Northwest University Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Key Laboratory of Agricultural Water Resources Center for Agricultural Resources Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences College of Tourism and Environment Ankang University

Stable oxygen and hydrogen isotopic compositions(δ^(18)O and δD) of plant xylem water and its potential water sources can provide new information for studying water sources, competitive interactions and water use patterns of plants. The contributions of different water sources to three plants, Hedysarum scoparium(HS), Caragana Korshinskii(CK) and Artemisia ordosica(AO), were investigated in the artificial sand-fixed vegetation of Shapotou, the southeastern margin of the Tengger Desert of northwestern China, based on meteorological data and δ^(18)O and δD values of precipitation, groundwater, soil water and xylem water of HS, CK and AO. Our results indicated that soil water infiltration through precipitation was the main water source of the artificial sand-fixed vegetation. Obvious differences in soil water content and in δ^(18)O of soil water and xylem water were found among different seasons. No relationship was found between the δ^(18)O in plant xylem water and in soil water in January. The same water use patterns were found in CK, HS and AO in May, suggesting they have the same water sources. The different water sources of CK, HS and AO in August indicate that water competition occurred. In addition, the main water sources of CK, HS and AO in August mainly come from shallow soil water, while they use relatively deep soil water in May. This phenomenon is related to the differences of soil water content throughout soil profile, precipitation, transpiration and water competition under different growth periods. The water use patterns of CK, HS and AO respond to soil water content throughout the soil profile and their competition balance for water uptake during different growth season. The results indicate that these sandfixed plants have developed into a relatively stable stage and they are able to regulate their water use behavior as a response to the environmental conditions, which reinforces the effectiveness of plantation of native shrubs without irrigation in de

关键词： Plant water source Stable hydrogen and oxygen isotopes Artificial and sand-fixed vegetation in Shapotou

Tetragonal (Ba, Ca) (Zr, Ti)O_(3) textured ceramics with enhanced piezoelectric response and superior temperature stability

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Journal of Materiomics 2022年第2期8卷 366-374页

作者： Qiangwei Kou Bin yang yuan Sun Shuai yang Linjing liu Hang xie Yunfei Chang Shantao zhang fei Li Functional Materials and Acousto-Optic Instruments Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin150080China Electronic Materials Research Laboratory(Key Lab of Education Ministry) State Key Laboratory for Mechanical Behavior of Materials and School of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'an710049China National Laboratory of Solid State Microstructures and College of Engineering and Applied Science Nanjing UniversityNanjing210093China

Lead-free ceramics with both high piezoelectric response and good temperature stability are urgently demanded for electromechanical conversion ***,owing to coexistence of poly-morphic phases near room temperature(RT),enhanced piezoelectric properties were usually achieved with occurrence of strong temperature dependence in modified BaTiO_(3)(BT)-based *** this work,we demonstrate that tailoring grain orientations of tetragonal BT-based ceramics can effectively produce substantially enhanced and thermally stabilized piezoelectric ***c-andc-oriented tetragonal(Ba_(0.85)Ca_(0.15))(Zr_(0.05)Ti_(0.95))O_(3)(BCZT)ceramics with texture degrees F>90%were synthesized via templated grain ***,the ceramics textured along thec polar axis show much higher microscopic and macroscopic piezoelectric properties than those with nonpolarc texture,indicating an“extender”ferroelectricity *** with randomly oriented samples,thec-oriented ceramics exhibit simultaneously~1.6 times higher piezoelectric strain d_(33)^(*)(~760 pm/V),4.4 times higher piezoelectric figure of merit d_(33)×g_(33)(8.8×10^(-12) m^(2)/N),and better temperature stability(strain variation≤5%between RT and 110℃).Such thermally stabilized strain response can be mainly attributed to wide temperature range of tetragonal phase and stable domain *** work provides a promising route for further developing lead-free piezoceramics with high and temperature-insensitive performance,which can greatly broaden their application areas.

关键词： Lead-free Textured ceramics Grain orientation Piezoelectric properties Temperature stability

Reply to: The letter to the editor "Laparoscopic liver resection for malignancies confined to Couinaud's segment VII in the robotic surgery era" by Zizzo et al.

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Hepatobiliary Surgery and Nutrition 2019年第4期8卷 445-446页

作者： Ning-yuan Wen Yong-gang Wei fei liu Hai-Li zhang Department of Liver Surgery Liver Transplantation Center West China Hospital of Sichuan University Chengdu 610041 China

We would like to thank you and other reviewers for reading our papers and sharing valuable comments. We are also appreciative of your conscientiousness and broad knowledge on relevant research fields. Recent advances in robotic hepatectomy (RH) were briefly summarized in your letter, especially its non-inferiority compared with the conventional laparoscopic liver resection (LLR). Here, we would like to address several points relevant to the comments.

关键词： resection letter surgery

FAR591 promotes the pathogenesis and progression of SONFH by regulating Fos expression to mediate the apoptosis of bone microvascular endothelial cells

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Bone Research 2023年第2期11卷 398-415页

作者： fei zhang Lei Wei Lei wang Tao wang Zhihong xie Hong Luo Fanchao Li Jian zhang Wentao Dong gang liu Qinglin Kang Xuesong Zhu Wuxun Peng Department of Emergency Orthopedics The Affiliated Hospital of Guizhou Medical UniversityGuiyangGuizhou550004China School of Clinical Medicine Guizhou Medical UniversityGuiyangGuizhou 550004China Department of Orthopedics Rhode Island HospitalBrown UniversityProvidenceRhode Island02903USA Department of Orthopedics Shanghai Jiao Tong University Affiliated Sixth People's HospitalShanghai 200233China Department of Orthopedics The First Affiliated Hospital of Soochow UniversitySuzhouJiangsu215000China

The specific pathogenesis of steroid-induced osteonecrosis of the femoral head(SONFH)is still not fully understood,and there is currently no effective early *** the role and mechanism of long noncoding RNAs(lnc RNAs)in the pathogenesis of SONFH will help reveal the pathogenesis of SONFH and provide new targets for its early prevention and *** this study,we first confirmed that glucocorticoid(GC)-induced apoptosis of bone microvascular endothelial cells(BMECs)is a pre-event in the pathogenesis and progression of ***,we identified a new lnc RNA in BMECs via lnc RNA/m RNA microarray,termed Fosassociated linc RNA ENSRNOT00000088059.1(FAR591).FAR591 is highly expressed during GC-induced BMEC apoptosis and femoral head *** of FAR591 effectively blocked the GC-induced apoptosis of BMECs,which then alleviated the damage of GCs to the femoral head microcirculation and inhibited the pathogenesis and progression of *** contrast,overexpression of FAR591 significantly promoted the GC-induced apoptosis of BMECs,which then aggravated the damage of GCs to the femoral head microcirculation and promoted the pathogenesis and progression of ***,GCs activate the glucocorticoid receptor,which translocates to the nucleus and directly acts on the FAR591 gene promoter to induce FAR591 gene ***,FAR591 binds to the Fos gene promoter(–245–51)to form a stable RNA:DNA triplet structure and then recruits TATA-box binding protein associated factor 15 and RNA polymerase II to promote Fos expression through transcriptional *** activates the mitochondrial apoptotic pathway by regulating the expression of Bcl-2 interacting mediator of cell death(Bim)and P53 upregulated modulator of apoptosis(Puma)to mediate GC-induced apoptosis of BMECs,which leads to femoral head microcirculation dysfunction and femoral head *** conclusion,these results confirm the mechanistic link between lnc RNAs and the p

关键词： pathogenesis prevention inhibited

Application of a novel computer-assisted surgery system in percutaneous nephrolithotomy:A controlled study

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World Journal of Clinical Cases 2022年第18期10卷 6039-6049页

作者： fei Qin Ye-Feng Sun Xin-Ning wang Bin Li Zhi-Lei zhang Ming-Xin zhang fei xie Shuai-Hong liu Zi-Jie wang yuan-Chao Cao Wei Jiao Department of Urology The Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

BACKGROUND Most complex renal stones are managed primarily with percutaneous nephrolithotomy(PCNL).However,PCNL is still a great challenge for surgeons because of poor comprehension on complex adjacent *** techniques are required to assist in planning and *** To apply and evaluate the Hisense computer-assisted surgery(CAS)system in *** A total of 60 patients with complex renal stones were *** patients in the CAS group had three-dimensional(3 D)virtual models constructed with the CAS *** model assisted in planning and navigating in the CAS *** patients in the control group planned and navigated as standard PCNL,without the application of the CAS *** rate of one attempt,operation time,initial stone-free rate,decrease in hemoglobin,and complications were collected and *** There were no statistically significant differences in the baseline characteristics or planning *** success rate of one puncturing attempt(90%vs 67%,P=0.028)and the initial stone-free rate(87%vs 63%,P=0.037)were significantly higher in the CAS ***,there were no statistically significant differences in the operation time(89.20±29.60 min vs 92.33±33.08 min,P=0.859)or in the decrease in hemoglobin(11.07±8.32 g/L vs 9.03±11.72 g/L,P=0.300)between the CAS group and the control *** statistically significant differences in the incidence of complications(Clavien-Dindo grade≥2)were *** Compared with standard PCNL,CAS-assisted PCNL had advantages in terms of the puncturing success rate and stone-free *** Hisense CAS System was recommended to assist in preoperative planning and intraoperative navigation for an intuitive,precise and convenient PCNL.

关键词： Computer-assisted surgery system Percutaneous nephrolithotomy Three-dimensional reconstruction Planning Navigation