检索结果-南通市图书馆

Aircraft Detection for HR SAR Images in Non-homogeneous Background Using GGMD-Based Modeling

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2019年第6期28卷 1271-1280页

作者： HU Hao HUANG Lanqing YU wenxian Shanghai Key Laboratory of Intelligent Sensing and Recognition Shanghai Jiao Tong University

In the problem of aircraft detection for High resolution(HR) Synthetic aperture radar(SAR)images, the background areas commonly contain multiple land cover types, such as runways and grassland. The conventional Constant false alarm rate(CFAR) detection in these non-homogeneous backgrounds with homogeneous assumption leads to unreliable detection results. This paper constructs a one-stage detection method based on the Generalized gamma mixture distribution(GGMD),which is regarded as a competitive and applicable model for combining the advantages of the Generalized gamma distribution(GGD) and the Finite mixture model(FMM).In order to evaluate the availability of the proposed algorithm, HR SAR images for aircraft detection from different product types and with various resolutions are examined. Compared with the CFAR algorithms based on the Gamma distribution, the GGD, and the gamma mixture distribution, the proposed algorithm demonstrates its availability and effectiveness for aircraft detection in HR SAR images in non-homogeneous background.

关键词： Constant false alarm rate(CFAR) Generalized gamma mixture distribution(GGMD) Expectation maximization(EM) Synthetic aperture radar(SAR)

MOFs derived FeNi_(3) nanoparticles decorated hollow N-doped carbon rod for high-performance oxygen evolution reaction

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Green Energy & Environment 2022年第3期7卷 423-431页

作者： Gaopeng Liu Bin wang Lin wang wenxian Wei Yu Quan Chongtai wang Wenshuai Zhu Huaming Li Jiexiang Xia School of Chemistry and Chemical Engineering Institute for Energy ResearchJiangsu University301 Xuefu RoadZhenjiang212013China Testing Center Yangzhou UniversityYangzhouJiangsu225009China School of Chemistry and Chemical Engineering The Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan ProvinceHainan Normal UniversityHaikouHainan571158China

The sluggish electrochemical oxygen evolution reaction(OER) is a crucial process for clean energy conversion *** preparation of non-precious electrocatalysts with high performance for OER is still a main ***,we report a FeNi_(3) nanoparticles incorporated on N-doped hollow carbon rod with extraordinary performance toward OER by in situ annealing the Ni-doped Fe based metal-organic frameworks(MOFs) ***,the pristine N atoms of MOFs doped into carbon frameworks can enhance the electrical conductivity,boost electron mass transport and electron transfer,and construct more active ***,constructing the Fe-Ni alloy structure can facilitate the formation of O-O bond,optimize the free energy for intermediate adsorption and improve OER *** as-prepared Fe-Ni bimetal decorated hollow N-doped nanocarbon hybrid structure possesses superior OER performance,which is surpass commercial IrO_(2) at a overpotential of only 340 mV to achieve the current density of 10 mA cm^(-2),as well as a small Tafel slope of 86.67 mV dec^(-1) in alkaline *** Fe-Ni alloy/hollow N-doped nanocarbon hybrid structure shining the bright future for obtaining earth-abundant and superior efficient anode OER electrocatalyst.

关键词： alloy performance carbon

Structural Basis of RACK7 PHD Domain to Read a Pediatric Glioblastoma-Associated Histone Mutation H3.3G34R

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2021年第9期39卷 2433-2440页

作者： wenxian Lan Ze Li Fangfang Jiao Chunxi wang Rui Guo Chunyang Cao State Key Laboratory of Bioorganic and Natural Product Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Ungling RoadShanghai 200032China Fudan University Shanghai Cancer Center Institute of Biomedical SciencesState Key Laboratory of Genetic Engineering and Shanghai Key Laboratory of Medical EpigeneticsShanghai Medical College of Fudan UniversityShanghai 200032China Center for Medical Research and Innovation Shanghai Pudong HospitalFudan UniversityPudong Medical Centerand the Shanghai Key Laboratory of Medical Epigeneticsthe International Co-laboratory of Medical Epigenetics and MetabolismMinistry of Science and TechnologyInstitutes of Biomedical SciencesFudan UniversityShanghai 200032China University of Chinese Academy of Science No.19AYuquan RoadShijingshan DistrictBeijing 100049China

Histone point mutations,including missense mutations on histone H3 at positions 27(K27M),34(G34R/V,G34W,G34L)and 36(K36M),were identified as potential cancer driver mutations.H3.3G34R/V mutations account for pediatric glioblastomas(GBM).RACK7(also known as ZMYND8,PRKCBP1)was recently reported to specifically bind H3.3G34R through its PHD(plant homedomain)domain(PHDRACK7)in vitro and in H3.3G34R pediatric glioblastoma cells,playing key roles in H3.3G34R-mediated gene ***,we provided both biochemical and NMR structural evidences that PHDRACK7 recognized histone H3.3G34R mutant via a mechanism distinet from all other reported PHD *** the reported residue D104,two new sites D108 and L121 of PHD^(RACK7) were found necessary for the interactions between PHD^(RACK7) and histone H3.3G34R *** results provided a potential molecular basis for pediatric GBM driven by the H3.3G34R mutation.

关键词： RACK7 H3.3G34R Interaction NMR Structure

Molten salt assisted self-activated carbon with controllable architecture for aqueous supercapacitor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2023年第25期156卷 107-117页

作者： Wei Zhang wenxian Li Sean Li School of Materials Science and Engineering The University of New South WalesKensingtonNew South Wales 2052Australia UNSW Materials and Manufacturing Futures Institute The University of New South WalesKensingtonNew South Wales 2052Australia

Activated carbons have been widely employed as electrode materials of aqueous supercapacitors but the use of hazardous and corrosive activating agents challenges conventional activation ***,using a unique molten salt assisted self-activation technique,we have devised an eco-friendly and simple method to synthesize oxygen-rich hierarchical porous carbon with controllable *** of sodium carboxymethylcellulose and NaCl was pyrolyzed in one step,creating in-situ produced Na_(2)CO_(3)-NaCl molten salt that carried out the activation ***2 CO3 acts as the activating agent in the reaction media of NaCl during the self-activation *** obtained carbon exhibited a remarkable specific capacitance of 278 F g^(−1) at 0.5 A g^(−1) and retained 76%capacitance at 50 A g^(−1) in a three-electrode *** fabricated aqueous coin cell achieved 81%capacitance retention at 50 A g^(−1) and the highest specific energy density of 12.8 Wh kg^(−1) at 214.6 W kg^(−1),which are superior compared to the commercial activated carbon(64%at 50 A g^(−1) and 8.4 Wh kg^(−1) at 194.8 W kg^(−1)).Moreover,capacitance fading was not observed after 10000 cycles at 5 A g^(−1).Considering the species diversity and low cost of self-salt polymers on the market,this strategy will expect to become a scalable approach for synthesizing high-performance capacitive carbons.

关键词： Molten salt Self-template Porous carbon Controllable architecture Aqueous supercapacitors

A Multicarrier Phase-Coded Waveform Design Scheme for Joint Radar and Communication System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2021年第4期30卷 769-780页

作者： DU Zhen ZHANG Zenghui YU wenxian Shanghai Key Laboratory of Intelligent Sensing and Recognition School of Electronic Information and Electrical EngineeringShanghai Jiao Tong University

A Multicarrier phase-coded(MCPC)waveform design scheme with two steps for Joint radar and communication(JRC) system is developed. Firstly, an integrated MCPC waveform design method is addressed by simultaneously maximizing the Signal-to-clutter-to-noise ratio(SCNR) and the Shannon capacity, subject to both the Integrated sidelobe level ratio(ISLR) constraint and the energy constraint. This model is theoretically proved to be a convex optimization problem with respect to the absolute squares of the transmit weights corresponding to different subcarriers, of which the analytical result is also discussed. Subsequently, by further optimizing the phases of the transmit weights, minimizing the Peak to average power ratio(PAPR) for JRC system is recast as a Semidefinite programming(SDP) problem, which can be effectively solved with the Semidefinite relaxation(SDR) technique via Eigenvalue decomposition(EVD)or Complex Gaussian randomization(CGR). Numerical examples are provided to verify the effectiveness of the proposed scheme.

关键词： Waveform design Joint radar and communication system Multicarrier phase-coded waveform Peak to average power ratio

Crystal Structure of Cytidine Deaminase Human APOBEC3F Chimeric Catalytic Domain in Complex with DNA

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2018年第12期36卷 1241-1248页

作者： Chao Cheng Tianlong Zhang Chunxi wang wenxian Lan Jianping Ding Chunyang Cao State Key Laboratory of Bioorganic and Natural Product Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai200032China Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences320 Yueyang RoadShanghai200031China University of Chinese Academy of Sciences No.19(A)Yuquan RoadShijingshan DistrictBeijing 100049China

APOBEC3F (A3F) demonstrates antivirus activity through its A3F‐CD2 domain catalyzing deamination of cytidine in target motif 5’‐TC in viral cDNA during reverse transcription. But structural basis is unclear. Previously, chimeric A3F‐CD2 (i.e., A3Fc‐CD2, where residues 195—217 of A3F‐CD2 were replaced with residues 197—221 of A3G‐CD2) was found soluble with deamination activity. Here, we report crystal structures of A3Fc‐CD2 in complexes with single‐stranded DNA (5’‐ATTTT5C6A7A8T9T‐3’ and 5’‐ATTTT5C6A7A8C9T‐3’) at resolutions of 1.98 Å and 2.30 Å, respectively. They demonstrate that one molecular DNA binds two A3Fc‐CD2 molecules (monomers A and B) at two sites, distinct from the reported complex structure of human A3F‐CD2 with a 10‐dT DNA. The first site is formed by residues Tyr333, Lys358 and Tyr359 in monomer A, far away from Zn2+ binding motif, interacting with bases dT5, dC6 and dA7 through π‐π stacking and hydrogen bonds. The second site is composed of Trp277, Y307YFW310 near to Zn2+ binding region in monomer B, interacting with base dA8, mainly through π‐π stacking and hydrophobic interactions, determining deamination preference of DNA sequence. Subsequent biochemical investigations further confirm the contribution of these residues to DNA binding and deamination activities. These studies are helpful to understand the mechanism how A3F‐CD2 catalyzes cytidine deamination.

关键词： APOBEC3F HIV‐1 deamination DNA structure

A hybrid data driven framework considering feature extraction for battery state of health estimation and remaining useful life prediction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Green Energy and Intelligent Transportation 2024年第2期3卷 50-59页

作者： Yuan Chen wenxian Duan Yigang He Shunli wang Carlos Fernandez School of Artificial Intelligence Anhui UniversityHefei 230009China State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130022China School of Electrical Engineering and Automation Wuhan UniversityWuhan 430000China School of Information Engineering Southwest University of Science and TechnologyMianyang 621010China School of Pharmacy and Life Sciences Robert Gordon UniversityAberdeenAB10-7GJUK

Battery life prediction is of great significance to the safe operation,and reduces the maintenance *** paper proposes a hybrid framework considering feature extraction to achieve more accurate and stable life prediction performance of the *** feature extraction,eight features are obtained to fed into the life prediction *** hybrid framework combines variational mode decomposition,the multi-kernel support vector regression model and the improved sparrow search algorithm to solve the problem of data backward,uneven distribution of high-dimensional feature space and the local escape ability,*** parameters of the estimation model are obtained by introducing the elite chaotic opposition-learning strategy and adaptive weights to optimize the sparrow search *** algorithm can improve the local escape ability and convergence performance and find the global *** comparison is conducted by dataset from National Aeronautics and Space Administration which shows that the proposed framework has a more accurate and stable prediction *** with other algorithms,the SOH estimation accuracy of the proposed algorithm is improved by 0.16%–1.67%.With the advance of the start point,the RUL prediction accuracy of the proposed algorithm does not change much.

关键词： State of heath Improved sparrow search algorithm Remaining useful life Variational mode decomposition Multi-kernel support vector regression Feature extraction

Ultrasound-Assisted Transient Liquid Phase Bonding of Magnesium Alloy Using Brass Interlayer in Air

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2017年第6期33卷 567-572页

作者： Zhiwei Lai Ruishan Xie Chuan Pan Xiaoguang Chen Lei Liu wenxian.wang Guisheng Zou School of Materials Science and Engineering Tsinghua University Department of Mechanical Engineering Key Laboratory for Advanced Manufacturing by Materials Processing Technology Tsinghua University China Iron & Steel Research Institute Group R&D Department Yongtai Electric (Dong Guan) Co. Ltd College of Materials Science and Engineering Shanxi Key Laboratory of Advanced Magnesium-based Materials Taiyuan University of Technology

The microstructure evolution and oxide film behavior in ultrasound-assisted transient liquid phase（U-TLP） bonding of Mg alloy were investigated by applying different ultrasonic time at 460？C with brass interlayer in air. The results indicated that with increasing ultrasonic time, brass interlayer disappeared gradually and the Mg-Cu-Zn eutectic compounds were formed. The eutectic compounds in the joint decreased as the ultrasonic time increased further. The oxide removal process was divided into four steps. Continuous oxide film at the interface was partially fractured by ultrasonic vibration,and then suspended into liquid by undermining eutectic reaction. After that, the suspended oxide film was broken into small oxide fragments by ultrasonic cavitation effect, which was finally squeezed out of the joint by ultrasonic squeeze action. In addition, the mechanical properties of the joints were investigated. The maximum shear strength of the joint reached 105 MPa, which was 100% of base metal.

关键词： Magnesium alloy Bonding Ultrasound Oxide film Microstructure

PREPARATION　OF　AMORPHOUS　Mo_5Si_3　BY　MECHANICAL　ALLOYING　AND　THE　CRYSTALLIZATION

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 1995年第4期5卷 118-121页

作者： Li, Mingwei Tang, Renzheng Li, wenxian Central South Univ of Technology Changsha China

ＰＲＥＰＡＲＡＴＩＯＮＯＦＡＭＯＲＰＨＯＵＳＭｏ_５Ｓｉ_３ＢＹＭＥＣＨＡＮＩＣＡＬＡＬＬＯＹＩＮＧＡＮＤＴＨＥＣＲＹＳＴＡＬＬＩＺＡＴＩＯＮＬｉＭｉｎｇｗｅｉ；ＴａｎｇＲｅｎｚｈｅｎｇ；ＬｉＷｅｎｘｉａｎ（Ｄｅｐａｒ... 详细信息

ＰＲＥＰＡＲＡＴＩＯＮＯＦＡＭＯＲＰＨＯＵＳＭｏ_５Ｓｉ_３ＢＹＭＥＣＨＡＮＩＣＡＬＡＬＬＯＹＩＮＧＡＮＤＴＨＥＣＲＹＳＴＡＬＬＩＺＡＴＩＯＮＬｉＭｉｎｇｗｅｉ；ＴａｎｇＲｅｎｚｈｅｎｇ；ＬｉＷｅｎｘｉａｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳ...

关键词： amorphous alloy mechanical alloying Mo5Si3 crystallization