检索结果-南通市图书馆

Sensing Matrix Optimization for Random Stepped-Frequency Signal Based on Two-Dimensional Ambiguity Function

Chinese Journal of Electronics 2024年第1期33卷 161-174页

作者： Mingjiu LYU Hao CHEN Jun yang xia WU Ming ZHOU xiaoyan MA Radar NCO School Air Force Early Warning Academy Department of Early Warning Technology Air Force Early Warning Academy

Compressive sensing technique has been widely applied to achieve range-Doppler reconstruction of high frequency radar by utilizing sparse random stepped-frequency(SRSF) signal, which can suppress the complex electromagnetic interference and greatly reduce the coherent processing interval. An important way to improve the performance of sparse signal reconstruction is to optimize the sensing matrix(SM). However, the existing research on the SM optimization needs to design a measurement matrix with superior performance, which needs a large amount of computation and does not consider the influence of the waveform parameters design. In order to improve the superior reconstruction performance, a novel SM optimization approach for SRSF signal is proposed by using two-dimensional ambiguity function(TDAF) in this paper. Firstly, based on the two-dimensional sparse reconstruction model of the SRSFs, the internal relationship between the waveform parameters and the SM was derived. Secondly, the SM optimization problem was directly transformed into the waveform design of SRSFs. Furthermore, on the basis of analyzing the relationship between the mutual coherence matrix of SM and the TDAF matrix of SRSFs, the purpose of optimizing the SM can be achieved by designing the TDAF of the SRSFs. Based on this analysis, a sparse waveform optimization method with joint constraints of maximum and mean sidelobes of the TDAF by using the genetic algorithm was derived. Compared with the traditional SM optimization method, our method not only avoids generating a new measurement matrix, but also further reduces the complexity of the waveform optimization. Simulation experiments verified the effectiveness of the proposed method.

关键词： Correlation Computational modeling Electromagnetic interference Optimization methods Signal reconstruction High frequency radar Sensors

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Excess pore pressure behavior and evolution in deep coalbed methane reservoirs

引用

International Journal of Mining Science and Technology 2024年第6期34卷 763-781页

作者： Changqing Liu Zhaobiao yang Yong Qin xia Yan Yunhai Wang Zhe Wang Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process Ministry of EducationChina University of Mining and TechnologyXuzhou 221008China School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221116China National Engineering Research Center of Coalbed Methane Development&Utilization Beijing 100095China PetroChina Coalbed Methane Company Limited Beijing 102200China SINOPEC East China Oil and Gas Company Nanjing 210000China

Deep coalbed methane(DCBM),an unconventional gas reservoir,has undergone significant advancements in recent years,sparking a growing interest in assessing pore pressure dynamics within these *** some production data analysis techniques have been adapted from conventional oil and gas wells,there remains a gap in the understanding of pore pressure generation and evolution,particularly in wells subjected to large-scale hydraulic *** address this gap,a novel technique called excess pore pressure analysis(EPPA)has been introduced to the coal seam gas industry for the first time to our knowledge,which employs dual-phase flow principles based on consolidation *** technique focuses on the generation and dissipation for excess pore-water pressure(EPWP)and excess pore-gas pressure(EPGP)in stimulated deep coal *** have been developed respectively and numerical solutions have been provided using the finite element method(FEM).Application of this model to a representative field example reveals that excess pore pressure arises from rapid loading,with overburden weight transferred under undrained condition due to intense hydraulic fracturing,which significantly redistributes the weight-bearing role from the solid coal structure to the injected fluid and liberated gas within artificial pores over a brief ***,field application indicates that the dissipation of EPWP and EPGP can be actually considered as the process of well production,where methane and water are extracted from deep coalbed methane wells,leading to consolidation for the artificial ***,history matching results demonstrate that the excess-pressure model established in this study provides a better explanation for the declining trends observed in both gas and water production curves,compared to conventional practices in coalbed methane reservoir engineering and petroleum *** research not only enhances the understanding of DCBM re

关键词： Deep coalbed methane Consolidation Excess pore-water pressure Excess pore-gas pressure Production data analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Time-resolved ultra-small-angle X-ray scattering beamline(BL10U1)at SSRF

引用

Nuclear Science and Techniques 2024年第2期35卷 6-19页

作者： Wen-Qiang Hua Chun-Ming yang Ping Zhou Feng Tian Jin-You Lin Yu-Zhu Wang xiao-Yun Li xia-Ran Miao Chun-xia Hong Qiu-Shi Huang Xin-tong Zhao Yong-Feng Men Jie Wang Xing-Yu Gao Xiu-Hong Li Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Key Laboratory of Advanced Micro Structural Materials MOEInstitute of Precision Optical EngineeringSchool of Physics Science and EngineeringTongji UniversityShanghai 200092China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The construction of a new beamline,BL10U1,was completed at the Shanghai synchrotron radiation facility in *** multipurpose beamline was designed to provide X-ray scattering techniques such as ultra-small-angle X-ray scattering(USAXS),small-angle X-ray scattering(SAXS),wide-angle X-ray scattering,and microfocus SAXS(μSAXS)for a broad user *** realize fast time-resolved USAXS experiments,the beamline adopted an in-vacuum undulator with a total length of 1.6 m as the photon *** in-house cryogenic-cooled double multilayer monochromator was installed to deliver a photon flux of approximately 10^(13) photons/s at a photon energy of 10 *** three-year successful operation of this beamline demonstrated that the monochromator operated smoothly,as ***10U1 has three end stations in succession:USAXS end station,μSAXS end station,and end station for industrial *** minimum scattering vector q~0.0042 nm^(-1) at 10 keV can be achieved at the USAXS end station equipped with a 28 m-long and 1.8 m-diameter vacuum flight *** theμSAXS end station,a beam spot of less than 10×8μm was achieved for micro-SAXS *** contrast,in situ experimental instruments up to 5 m high and 8 m wide can be mounted at the industrial application end station,which offers industrial scientists the opportunity to use their large industrial ***10U1 opens up a new capability to investigate phenomena such as non-equilibrium and dynamic processes of materials with a wide length scale from angstroms to micrometers with millisecond time *** this paper,we also report beamline design considerations and commissioning results.

关键词： Synchrotron radiation Ultra-small-angle X-ray scattering Micro small-angle X-ray scattering USAXS Time resolved μSAXS

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Statistical Channel Modeling for Indoor VLC Communications Based on Channel Measurements

引用

China Communications 2024年第1期21卷 131-147页

作者： Shuo Liu Pan Tang Jianhua Zhang Yue Yin Yu tong Baobao Liu Guangyi Liu Liang xia State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China China Mobile Research Institute Beijing 100053China

Visible light communication(VLC)has attracted much attention in the research of sixthgeneration(6G)***,channel modeling is the foundation for designing efficient and robust VLC *** this paper,we present extensive VLC channel measurement campaigns in indoor environments,i.e.,an office and a *** on the measured data,the large-scale fading characteristics and multipath-related characteristics,including omnidirectional optical path loss(OPL),K-factor,power angular spectrum(PAS),angle spread(AS),and clustering characteristics,are analyzed and modeled through a statistical *** on the extracted statistics of the above-mentioned channel characteristics,we propose a statistical spatial channel model(SSCM)capable of modeling multipath in the spatial ***,the simulated statistics of the proposed model are compared with the measured *** instance,in the office,the simulated path loss exponent(PLE)and the measured PLE are 1.96and 1.97,***,the simulated medians of AS and measured medians of AS are 25.94°and 24.84°,***,the fact that the simulated results fit well with measured results has demonstrated the accuracy of our SSCM.

关键词： channel characteristics channel measurement channel modeling 6G spatial lobe VLC

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Pathological mechanism of immune disorders in diabetic kidney disease and intervention strategies

引用

World Journal of Diabetes 2024年第6期15卷 1111-1121页

作者： tong Zhou Yi-Lin Fang Tian-Tian Tian Gui-xia Wang Department of Endocrinology and Metabolism The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina National-Local Joint Engineering Laboratory of Animal Models for Human Diseases Jilin UniversityChangchun 130021Jilin ProvinceChina School of Public Health Jilin UniversityChangchun 130021Jilin ProvinceChina

Diabetic kidney disease is one of the most severe chronic microvascular complications of diabetes and a primary cause of end-stage renal *** studies have shown that renal inflammation is a key factor determining kidney damage during *** the development of immunological technology,many studies have shown that diabetic nephropathy is an immune complex disease,and that most patients have immune ***,the immune response associated with diabetic nephropathy and autoimmune kidney disease,or caused by ischemia or infection with acute renal injury,is different,and has a complicated pathological *** this review,we discuss the pathogenesis of diabetic nephropathy in immune disorders and the intervention mechanism,to provide guidance and advice for early intervention and treatment of diabetic nephropathy.

关键词： Diabetic kidney disease Immune disorders Pathological mechanism Intervention strategy Kidney damage Diabetic nephropathy Inflammasome Immunoglobulin

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Overcoming the Limits of Cross-Sensitivity:Pattern Recognition Methods for Chemiresistive Gas Sensor Array

引用

Nano-Micro Letters 2024年第12期16卷 285-341页

作者： Haixia Mei Jingyi Peng Tao Wang Tingting Zhou Hongran Zhao tong Zhang Zhi yang Key Lab Intelligent Rehabil&Barrier Free Disable(Ministry of Education) Changchun UniversityChangchun 130022People’s Republic of China Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China National Key Laboratory of Advanced Micro and Nano Manufacture Technology Department of Micro/Nano ElectronicsSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012People’s Republic of China

As information acquisition terminals for artificial olfaction,chemiresistive gas sensors are often troubled by their cross-sensitivity,and reducing their cross-response to ambient gases has always been a difficult and important point in the gas sensing *** recognition based on sensor array is the most conspicuous way to overcome the cross-sensitivity of gas *** is crucial to choose an appropriate pattern recognition method for enhancing data analysis,reducing errors and improving system reliability,obtaining better classification or gas concentration prediction *** this review,we analyze the sensing mechanism of crosssensitivity for chemiresistive gas *** further examine the types,working principles,characteristics,and applicable gas detection range of pattern recognition algorithms utilized in gas-sensing ***,we report,summarize,and evaluate the outstanding and novel advancements in pattern recognition methods for gas *** the same time,this work showcases the recent advancements in utilizing these methods for gas identification,particularly within three crucial domains:ensuring food safety,monitoring the environment,and aiding in medical *** conclusion,this study anticipates future research prospects by considering the existing landscape and *** is hoped that this work will make a positive contribution towards mitigating cross-sensitivity in gas-sensitive devices and offer valuable insights for algorithm selection in gas recognition applications.

关键词： Pattern recognition Sensor array Chemiresistive gas sensor Cross-sensitivity Artificial olfactory

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Thermochemical splitting of CO_(2) on perovskites for CO production: A review

引用

Journal of Energy Chemistry 2024年第3期90卷 464-485,I0011页

作者： Biduan Chen Harriet Kildahl Hui yang Yulong Ding Lige tong Li Wang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China School of Chemical Engineering University of BirminghamBirmingham B152TTUnited Kingdom Beijing Engineering Research Centre of Energy Saving and Environmental Protection Beijing 100083China

Energy supply dominated by fossil energy has been and remains the main cause of carbon dioxide emissions,the major greenhouse gas leading to the current grave climate change *** technical pathways have been proposed to address the *** capture and utilization(CCU) represents one of the approaches and thermochemical CO_(2) splitting driven by thermal energy is a subset of the CCU,which converts the captured CO_(2) into CO and makes it possible to achieve closed-loop carbon ***-active catalysts are among the most critical components of the thermochemical splitting cycles and perovskites are regarded as the most promising *** we review the latest advancements in thermochemical cycles based on perovskites,covering thermodynamic principles,material modifications,reaction kinetics,oxygen pressure control,circular strategies,and demonstrations to provide a comprehensive overview of the topical *** cycles based on such materials require the consideration of trade-off between cost and efficiency,which is related to actual material used,operation mode,oxygen removal,and heat *** of efforts have been made towards improving reaction rates,conversion efficiency and cycling stability,materials related research has been lacking-a key aspect affecting the performance across all above *** perovskites and composite perovskites arise recently as a potentially promising addition to material *** such materials,more effective oxygen removal would be needed to enhance the overall efficiency,for which thermochemical or electrochemical oxygen pumps could contribute to efficient oxygen removal as well as serve as means for inert gas *** integration of thermochemical CO_(2) splitting process with downstream fuel production and other processes could reduce costs and increase efficiency of the *** represents one of the directions for the future research.

关键词： Perovskite Thermochemical cycles CO_(2) splitting Fuel production Non-stoichiometric

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Particle size dependence of the microsegregation and microstructure in the atomized Ni-based superalloy powders:Theoretical and experimental study

引用

Journal of Materials Science & Technology 2024年第4期171卷 54-65页

作者： Jikang Li Mingsheng yang Yunfei Cai Yuanyuan Zhang Qingshuai Feng Jiantao Liu tong Liu Key Laboratory of Aerospace Materials and Performance(Ministry of Education)School of Materials Science and Engineering Beihang UniversityBeijing 100191China Central Iron and Steel Research Institute Beijing 100081China

The microstructure and microsegregation of atomized powder,which depend on their sizes,are of great importance to the mechanical properties of the consolidated bulk ***,it is necessary to reveal the relationship between particle size and powder *** effects of particle size on the so-lidification characterization of the atomized Ni-based superalloy powders were studied via finite element *** on the simulations,a model was developed to predict the microsegregation and mi-crostructure of atomized powders with different sizes and study the influence of thermal history on the powder attributes during the atomization *** radiation heat transfer and temperature gradi-ent within the rapid solidification alloy powders were taken into account in this *** validating the accuracy of the model,the predictions of the present model were compared with the microsegregation and microstructure of the specific size powder close to the screen mesh *** results showed that mi-crostructure depended primarily on the temperature gradient within the powder,while the solidification rate had a more significant effect on the *** model predicted microstructure features in agreement with the experiment,and for microsegregation,the deviations of prediction for most ele-ments were less than 10%.This work provides a new model to precisely predict the microsegregation and microstructure of the atomized alloy powders and sets a foundation to control the powder features for various engineering applications.

关键词： Particle size Solidification microstructure Microsegregation Numerical simulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A novel Ag/ZnO core-shell structure for efficient sterilization synergizing antibiotics and subsequently removing residuals

引用

Green Energy & Environment 2024年第2期9卷 366-377页

作者： Wenmei Han Wenli Wang Jie Fan Runping Jia Xuchun yang tong Wu Qingsheng Wu School of Chemical Science and Engineering Shanghai Key Laboratory of Chemical Assessment and SustainabilityInstitute of Advanced StudyTongji UniversityShanghai200092China College of Textile and Clothing Engineering China National Textile and Apparel Council Key Laboratory of Natural DyesSoochow UniversitySuzhou215123China Department of Urology Shanghai First People’s HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai200080China School of Materials Science and Engineering Shanghai Institute of TechnologyShanghai201418China

The massive use of antibiotics has led to the aggravation of bacterial resistance and also brought environmental pollution *** poses a great threat to human *** the dosage of antibiotics is reduced by increasing its bactericidal performance,the emergence of drug resistance is certainly delayed,so that there's not enough time for developing drug resistance during ***,we selected typical representative materials of metal Ag and semiconductor ZnO nano-bactericides to design and synthesize Ag/ZnO hollow core-shell structures(AZ for short).Antibiotics are grafted on the surface of AZ through rational modification to form a composite sterilization *** research results show that the antibacterial efficiency of the composite system is significantly increased,from the sum(34.7%+22.8%-57.5%)of the antibacterial efficiency of AZ and gentamicin to 80.2%,net synergizes 22.7%,which fully reflects the effect of 1+1>***,the dosage of antibiotics can be drastically reduced in this way,which makes both the possibility of bacterial resistance and medical expenses remarkably ***,residual antibiotics can be degraded under simple illumination using AZ-self as a photocatalyst,which cuts off the path of environmental *** short,such an innovative route has guiding significance for drug resistance.

关键词： Ag/ZnO hollow Core-shell structures Antibiotics Gentamycin Synergistic sterilization Photodegradation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Compact Filtering Antenna System with Wide-Angle Scanning Capability for V2I Communication

引用

Chinese Journal of Electronics 2024年第2期33卷 516-526页

作者： Chuang HAN tong LI Zhaolin ZHANG Ling WANG Guangwei yang School of Electronics and Information Northwestern Polytechnical University School of Electronic Engineering and Computer Science Queen Mary University of London

A compact filtering antenna system with wide-angle scanning is proposed for vehicle to infrastructure(V2I) communication which would handle complex communication scenarios. In this work, a wide beam filtering antenna is realized by using some inductive resistance structures such as metal pins and pillars, and capacitive structures such as slots, parasitical patches to produce the radiation nulls at two sides of the operating frequency band and improve the impedance matching in the passband. Meanwhile, the wide beam capability is also realized by the above structure. Furthermore, two H-and E-plane linear arrays are designed for the beam scanning capability with filtering characteristics based on the proposed antenna. To verify the proposed design concept, a prototype is fabricated and measured. The measurement and simulation agree well, demonstrating an excellent filtering characteristic with the operating frequency band from 3.18 to 3.45 GHz(about 8.1%), the high total efficiency of about 88%, and 3-d B-beamwidth of more than 100° and 120° in the above two arrays, respectively. Additionally, the proposed arrays can realize the beam scanning up to the coverage of 112° and 120° with a lower gain reduction and a good filtering characteristic, respectively.

关键词： Antenna measurements Radio frequency Resistance Slot antennas Filtering Communication systems Vehicle-to-infrastructure

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：