检索结果-南通市图书馆

The Establishment and Analysis of the Structural-Electromagnetic Coupling Model of the Electrostatically Controlled Deployable Membrane Antenna

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 Electronics 2024年第2期33卷 479-487页

作者： Shunji ZHANG Yongzhen gu Wang ZHONG Qinggang ZHANG Qingdao University of Science and Technology Key Laboratory of Electronic Equipment Structure Design of Ministry of Education Xidian University

A new structural-electromagnetic coupling(SEC) analysis based on quadratic elements is proposed to solve the mismatch problem between structural elements and electromagnetic grids of the electrostatically controlled deployable membrane antenna(ECDMA). Firstly, the ECDMA reflector surface is meshed and redefined by a series of quadratic elements. Without grid transformation, the calculating formulas for the far-field pattern of ECDMA are derived by the physical-optics method. Then the structural deformation of ECDMA is analyzed and the far-field pattern calculating formulas including deformation errors are developed. Simulation and experiment results show that the quadratic elements are effective and efficient in SEC analysis of the ECDMA, moreover, the electromagnetic grid size demand and the grid discretization error are reduced greatly.

关键词： Couplings Electrodes Analytical models Deformation Electromagnetic fields Electromagnetics Optimization

Layered Coded Cache Placement and Cooperative Delivery with Sharing Links in Satellite-Terrestrial Integrated Networks

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Communications 2024年第3期21卷 217-229页

作者： gu Shushi Chen Zihan Wu Yaonan Zhang Qinyu Wang Ye School of Electronic and Information Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China guangdong Provincial Key Laboratory of Aerospace Communication and Networking Technology Shenzhen 518055China Broadband Communications Research Department Pengcheng LaboratoryShenzhen 518052China

Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content delivery over the seamless global coverage area. However, the on-board supportable resources of a single satellite are extremely limited and lack of interaction with others. In this paper, we design a network model with two-layered cache deployment, i.e., satellite layer and ground base station layer, and two types of sharing links, i.e., terrestrial-satellite sharing(TSS) links and inter-satellite sharing(ISS) links, to enhance the capability of cooperative delivery over STINs. Thus, we use rateless codes for the content divided-packet transmission, and derive the total energy efficiency(EE) in the whole transmission procedure, which is defined as the ratio of traffic offloading and energy consumption. We formulate two optimization problems about maximizing EE in different sharing scenarios(only TSS and TSS-ISS),and propose two optimized algorithms to obtain the optimal content placement matrixes, *** results demonstrate that, enabling sharing links with optimized cache placement have more than 2 times improvement of EE performance than other traditional placement schemes. Particularly, TSS-ISS schemes have the higher EE performance than only TSS schemes under the conditions of enough number of satellites and smaller inter-satellite distances.

关键词： coded content placement cooperative delivery energy efficiency sharing links STINs

Flexible and Robust Functionalized Boron Nitride/Poly(p‑Phenylene Benzobisoxazole)Nanocomposite Paper with High Thermal Conductivity and Outstanding Electrical Insulation

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第2期16卷 423-437页

作者： Lin Tang Kunpeng Ruan Xi Liu Yusheng Tang Yali Zhang Junwei gu Chongqing Key Laboratory of Green Synthesis and Applications College of ChemistryChongqing Normal UniversityChongqing 401331People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China

With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming *** this work,“high-temperature solid-phase&diazonium salt decomposition”method is carried out to prepare benzidine-functionalized boron nitride(m-BN).Subsequently,m-BN/poly(pphenylene benzobisoxazole)nanofiber(PNF)nanocomposite paper with nacremimetic layered structures is prepared via sol–gel film transformation *** obtained m-BN/PNF nanocomposite paper with 50 wt%m-BN presents excellent thermal conductivity,incredible electrical insulation,outstanding mechanical properties and thermal stability,due to the construction of extensive hydrogen bonds andπ–πinteractions between m-BN and PNF,and stable nacre-mimetic layered ***λ∥andλ_(⊥)are 9.68 and 0.84 W m^(-1)K^(-1),and the volume resistivity and breakdown strength are as high as 2.3×10^(15)Ωcm and 324.2 kV mm^(-1),***,it also presents extremely high tensile strength of 193.6 MPa and thermal decomposition temperature of 640°C,showing a broad application prospect in high-end thermal management fields such as electronic devices and electrical equipment.

关键词： Poly(p-phenylene-2,6-benzobisoxazole)nanofiber Boron nitride Thermal conductivity Electrical insulation

Ag-doped CNT/HAP nanohybrids in a PLLA bone scaffold show significant antibacterial activity

在线全文

学校读者我要写书评

暂无评论

Bio-Design and Manufacturing 2024年第2期7卷 105-120页

作者： Cijun Shuai Xiaoxin Shi Kai Wang Yulong gu Feng Yang Pei Feng State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083China Institute of Additive Manufacturing Jiangxi University of Science and TechnologyNanchang 330013China College of Mechanical Engineering Xinjiang UniversityUrumqi 830017China

Bacterial infection is a major problem following bone implant ***,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good ***,wesynthesizedsilver(Ag)-dopedCNT/HAP(CNT/Ag-HAP)nanohybrids via the partial replacing of calcium ions(Ca2+)in the HAP lattice with silver ions(Ag+)using an ion doping technique under hydrothermal ***ﬁcally,the doping process was induced using the special lattice structure of HAP and the abundant surface oxygenic functional groups of CNT,and involved the partial replacement of Ca2+in the HAP lattice by doped Ag+as well as the in situ synthesis of Ag-HAP nanoparticles on CNT in a hydrothermal *** result-ing CNT/Ag-HAP nanohybrids were then introduced into a PLLA matrix via laser-based powder bed fusion(PBF-LB)to fabricate PLLA/CNT/Ag-HAP scaffolds that showed sustained antibacterial *** then found that Ag+,which pos-sesses broad-spectrum antibacterial activity,endowed PLLA/CNT/Ag-HAP scaffolds with this activity,with an antibacterial effectiveness of 92.65%.This antibacterial effect is due to the powerful effect of Ag+against bacterial structure and genetic material,as well as the physical destruction of bacterial structures due to the sharp edge structure of *** addition,the scaffold possessed enhanced mechanical properties,showing tensile and compressive strengths of 8.49 MPa and 19.72 MPa,***,the scaffold also exhibited good bioactivity and cytocompatibility,including the ability to form apatite layers and to promote the adhesion and proliferation of human osteoblast-like cells(MG63 cells).

关键词： Ag-doped Carbon nanotube/hydroxyapatite(CNT/HAP) Antibacterial properties Bone scaffold

The Choice of Mesh Size and Integration Points Number for the Electrostatically Controlled Membrane Antenna Structural-Electromagnetic Coupling Model

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2024年第2期33卷 443-448页

作者： Yongzhen gu Qinggang ZHANG Xiao YU guixu LI Qingdao University of Science and Technology

It is of great significance for the improvement of the computational efficiency of the electrostatically controlled membrane antenna(ECMA) structural-electromagnetic coupling model through the choice of appropriate mesh size and integration points number. In this paper, the physical optics formulation is used to analyze the radiation pattern of the ECMA surface, and the finite element method is applied to the electrostatic-structural coupling analysis. An expression for the relation between the mesh size, the focal length of the parabolic antenna, and the wavelength is developed based on the discretization error analysis of the triangular mesh approximating the parabolic surface. Moreover, the integration points number in each triangular mesh is determined by the numerical evaluation of the physical optics integral. Numerical results show that the proposed method improves the computing efficiency by about 87% compared with the referenced method.

关键词： Couplings Surface waves Error analysis Computational modeling Physical optics Numerical models Finite element analysis

Big Data Application Simulation Platform Design for Onboard Distributed Processing of LEO Mega-Constellation Networks

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Communications 2024年第7期21卷 334-345页

作者： Zhang Zhikai gu Shushi Zhang Qinyu Xue Jiayin School of Electronics and Information Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China guangdong Provincial Key Laboratory of Aerospace Communication and Networking Technology Shenzhen 518055China Broadband Communications Research Department Peng Cheng LaboratoryShenzhen 518000China

Due to the restricted satellite payloads in LEO mega-constellation networks(LMCNs),remote sensing image analysis,online learning and other big data services desirably need onboard distributed processing(OBDP).In existing technologies,the efficiency of big data applications(BDAs)in distributed systems hinges on the stable-state and low-latency links between worker ***,LMCNs with high-dynamic nodes and long-distance links can not provide the above conditions,which makes the performance of OBDP hard to be intuitively *** bridge this gap,a multidimensional simulation platform is indispensable that can simulate the network environment of LMCNs and put BDAs in it for performance *** STK's APIs and parallel computing framework,we achieve real-time simulation for thousands of satellite nodes,which are mapped as application nodes through software defined network(SDN)and container *** elaborate the architecture and mechanism of the simulation platform,and take the Starlink and Hadoop as realistic examples for *** results indicate that LMCNs have dynamic end-to-end latency which fluctuates periodically with the constellation *** to ground data center networks(GDCNs),LMCNs deteriorate the computing and storage job throughput,which can be alleviated by the utilization of erasure codes and data flow scheduling of worker nodes.

关键词： big data application Hadoop LEO mega-constellation multidimensional simulation onboard distributed processing

Progress in clinical diagnosis and treatment of colorectal cancer with rare genetic variants

在线全文

学校读者我要写书评

暂无评论

Cancer Biology & Medicine 2024年第6期21卷 473-483页

作者： Shuyi Chen Jing gu Kaichun Wu Xiaodi Zhao Yuanyuan Lu State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers and National Clinical Research Center for Digestive Diseases Xijing Hospital of Digestive DiseasesFourth Military Medical UniversityXi’an 710032China School of Basic Medical Sciences Fourth Military Medical UniversityXi’an 710032China

Targeted therapy is crucial for advanced colorectal cancer(CRC) positive for genetic drivers. With advances in deep sequencing technology and new targeted drugs, existing standard molecular pathological detection systems and therapeutic strategies can no longer meet the requirements for careful management of patients with advanced CRC. Thus, rare genetic variations require diagnosis and targeted therapy in clinical practice. Rare gene mutations, amplifications, and rearrangements are usually associated with poor prognosis and poor response to conventional therapy. This review summarizes the clinical diagnosis and treatment of rare genetic variations, in genes including erb-b2 receptor tyrosine kinase 2(ERBB2), B-Raf proto-oncogene, serine/threonine kinase(BRAF), ALK receptor tyrosine kinase/ROS proto-oncogene 1, receptor tyrosine kinase(ALK/ROS1), neurotrophic receptor tyrosine kinases(NTRKs), ret proto-oncogene(RET), fibroblast growth factor receptor 2(FGFR2), and epidermal growth factor receptor(EGFR), to enhance understanding and identify more accurate personalized treatments for patients with rare genetic variations.

关键词： Genetic variation gene mutation gene amplification gene rearrangement targeted therapy

An improved strain-softening constitutive model of granite considering the effect of crack deformation

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1202-1215页

作者： Yapeng Li Qiang Zhang Qiuxin gu Peinan Wu Binsong Jiang State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou221116China

This paper presents an improved strain-softening constitutive model considering the effect of crack deformation based on the triaxial cyclic loading and unloading test *** improved model assumes that total strain is a combination of plastic,elastic,and crack *** constitutive relationship between the crack strain and the stress was further *** evolutions of mechanical parameters,*** parameters,dilation angle,unloading elastic modulus,and deformation parameters of crack,with the plastic strain and confining pressure were *** the increase in plastic strain,the cohesion,friction angle,dilation angle,and crack Poisson's ratio initially increase and subsequently decrease,and the unloading elastic modulus and the crack elastic modulus nonlinearly *** increasing confining pressure enhances the strength and unloading elastic modulus,and decreases the dilation angle and Poisson's ratio of the *** theoretical triaxial compressive stress-strain curves were compared with the experimental results,and they present a good agreement with each *** improved constitutive model can well reflect the nonlinear mechanical behavior of granite.

关键词： Strain-softening Crack deformation effect Plastic shear strain Constitutive model

Modulated Degradation Rates of Bone Mineral-Like Calcium Phosphate Glass to Support the Proliferation and Osteogenic Differentiation of Bone Marrow-Derived Stem Cells

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

Journal of Bionic Engineering 2024年第4期21卷 1960-1974页

作者： Lizhe He Yuye Huang Jiafei gu Xiaoling Liu Jun Yin Xiang Gao Department of Neurosurgery The First Affiliated Hospital of Ningbo UniversityNingbo315010China Center for Medical and Engineering Innovation The First Affiliated Hospital of Ningbo UniversityNingbo315010China The State Key Laboratory of Fluid Power Transmission and Control Systems Key Laboratory of 3D Printing Process and Equipment of Zhejiang ProvinceSchool of Mechanical EngineeringZhejiang UniversityHangzhou310028China Faculty of Science and Engineering University of Nottingham Ningbo ChinaNingbo315100China

With an elemental composition similar to bone mineral,and the ability to release phosphorus and calcium that benefit bone regeneration,Calcium Phosphate Glass(CPG)serves as a promising component of bone tissue engineering ***,the degradation of CPG composites typically results in increased acidity,and its impact on bone-forming activity is less *** this work,we prepared 3D-printed composite scaffolds comprising CPG,Poly-ε-caprolactone(PCL),and various Magnesium Oxide(MgO)*** the MgO content effectively suppressed the degradation of CPG,maintaining a physiological pH of the degradation *** the degradation of CPG/PCL scaffolds resulted in upregulated apoptosis of Rat Bone Marrow-derived Stem Cells(rBMSC),scaffolds containing MgO were free from these negative impacts,and an optimal MgO content of 1 wt%led to the most pronounced osteogenic differentiation of *** work demonstrated that the rapid degradation of CPG impaired the renewability of stem cells through the increased acidity of the surrounding media,and MgO effectively modulated the degradation rate of CPG,thus preventing the negative effects of rapid degradation and supporting the proliferation and osteogenic differentiation of the stem cells.

关键词： Phosphate glass Polymer composites 3D printing Bone tissue engineering Scaffolds