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An Asymptotic UTD Solution for the Scattering by an Impedance Wedge at Skew Incidence

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Wuhan University Journal of Natural Sciences 2005年第5期10卷 855-861页

作者： yuan Fei XIAO Dong-shan ZHU Guo-qiang School of Electronic Information Wuhan UniversityWuhan 430072 Hubei China Kenbotong Communication LTD Foshan 528000 Guangdong China

Asymptotic expressions for the fields scattered by an isotropic impedance wedge at skew incidence are derived in the frame of the uniform geometrical theory of diffraction （UTD）. They are obtained by approximately solving the difference equations generated from impedance boundary con ditions （IBCs） in Maliuzhinets＇ approach. The method overcomes the discontinuity of the nonuniform evaluation given in the literature referred and can give out satisfactory numerical results.

关键词： electromagnetic scattering impedance wedge diffraction UTD

A topology control algorithm based on D-region fault tolerance

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Science China(Information Sciences) 2013年第7期56卷 33-41页

作者： SUN RuoZi WANG Yue yuan Jian shan XiuMing REN Yong Department of Electronic Engineering Tsinghua University Deparment of Applied Mathematics Harbin University of Science and Technology

In a wireless network, node failure due to either natural disasters or human intervention can cause network partitioning and other communication problems. For this reason, a wireless network should be fault tolerant. At present, most researchers use k-connectivity to measure fault tolerance, which requires the network to be connected after the failure of any up to k-1 nodes. However, wireless network node failures are usually spatially related, and particularly in military applications, nodes from the same limited area can fail together. As a metric of fault-tolerance, k-connectivity fails to capture the spatial relativity of faults and hardly satisfies the fault tolerance requirements of a wireless network design. In this paper, a new metric of fault-tolerance, termed D-region fault tolerance, is introduced to measure wireless network fault tolerance. A D-region fault tolerant network means that even after all the nodes have failed in a circular region with diameter D, it still remains connected. Based on D-region fault tolerance, we propose two fault-tolerant topology control algorithms--the global region fault tolerance algorithm (GRFT) and the localized region fault tolerance algorithm (LRFT). It is theoretically proven that both algorithms are able to generate a network with D-region fault tolerance. Simulation results indicate that with the same fault tolerance capabilities, networks based on both GRFT and LRFT algorithms have a lower transmission radius and lower logical degree.

关键词： fault tolerance connectivity spatial relativity topology control

Power allocation in cooperative MIMO systems under individual power constraints

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The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 1-6页

作者： YANG shan CUI Qi-mei XU Yue-qiao LUO yuan Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

allocation （PA） plays an important role in capacity improvement for cooperative multiple-input multipleoutput （Co-MIMO） systems. Many contributions consider a total power constraint （TPC） on the sum of transmit power from all nodes in addressing PA problem. However, in practical implementations, each transmit node is equipped with its own power amplifier and is limited by individual power constraint （IPC）. Hence these PA methods under TPC are not realizable in practical systems. Meanwhile, the PA problem under IPC is essential, but it has not been studied. This paper extends the traditional non-cooperative water-filling PA algorithm to IPC-based Co-MIMO systems. Moreover, the PA matrix is derived based on the compound channel matrix from all the cooperative nodes to the user. Therefore, the cooperative gain of the IPC-based Co-MIMO systems is fully exploited, and further the maximal instantaneous capacity is achieved. Numerical simulations validate that, under the same IPC conditions, the proposed PA scheme considerably outperforms the non-cooperative water-filling PA and uniform PA design in terms of ergodic capacity.

关键词： power allocation cooperative MIMO individual power constraint ergodic capacity

Clinical features and mismatch repair gene mutation screening in Chinese patients with hereditary nonpolyposis colorectal carcinoma

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World Journal of Gastroenterology 2004年第18期10卷 2647-2651页

作者： shan-RunLiu BoZhao Zhen-JunWang yuan-LianWan Yan-TingHuang DepartmentofSurgery PekingUniversityFirstHospitalBeijing100034China

AIM: Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominantly- inherited cancer-susceptibility syndrome that confers an increased risk for colorectal cancer and a variety of other tumors at a young age. It has been associated with germline mutations in five mismatch repair (MMR) genes (hMSH2, hMLH1, hPMS1, hPMS2, and hMSH6/GTBP). The great majority of germline mutations were found in hMSH2 and hMLH1. The purpose of this study was to analyze the clinical features of Chinese HNPCC patients and to screen hMSH2 and hMLH1 gene ***: Twenty-eight independent Chinese families were collected, of which 15 met Amsterdam criteria I and 13 met the Japanese clinical diagnosis criteria. The data were recorded including sex, site of colorectal cancer (CRC),age of diagnosis, history of synchronous and/or metachronous CRC, instance of extracolonic cancers, and histopathology of tumors. Peripheral blood samples were collected from all pedigrees after formal written consents were signed. PCR and denaturing high-performance liquid chromatography (DHPLC) were used to screen the coding regions of hMSH2 and hMLH1 genes. The samples showing abnormal DHPLC profiles were sequenced by a 377 DNA ***: One hundred and seventy malignant neoplasms were found in one hundred and twenty-six patients (multiple cancer in twenty-three), including one hundred and twentyseven CRCs, fifteen gastric, seven endometrial, and five esophageal cancers. Seventy-seven point eight percent of the patients had CRCs, sharing the features of early occurrence (average age of onset, 45.9 years) and of the right-sided predominance reported in the literature. In Chinese HNPCC patients, gastric cancer occurred more frequently, accounting for 11.9% of all cancers patients and ranking second in the spectrum of HNPCC predisposing cancers. Synchronous CRCs occurred less frequently, only accounting for 3.1% of the total CRCs. Twenty percent of the colorectal patients had metachronou

关键词：临床病例错配修补基因基因变异中国结直肠癌肿瘤 CRC 组织病理学

Synthesis of porous aromatic framework with Friedel–Crafts alkylation reaction for CO_2 separation

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Chinese Chemical Letters 2016年第9期27卷 1479-1484页

作者： Peng Cui Xiao-Fei Jing Ye yuan Guang-shan Zhu Key Laboratory of Polyoxometalate Science of Ministry of Education Department of Chemistry Northeast Normal University

A novel porous aromatic framework, PAF-8, derived from tetraphenylsilane as basic building unit, was successfully synthesized via Friedel-Crafts alkylation reaction. This PAF material had high thermal stability as well as high surface area （785 m^2 g^-1） calculated from the Brunauer-Emmett-Teller （BET） model. Meanwhile, PAF-8 possessed high performances in gas sorption and especially for CO2 separation.

关键词： Porous aromatic frameworks Friedel-Crafts alkylation Gas sorption CO2 separation Liquid vapor adsorption

Model for cascading network failures based on the nodes with different tolerance parameter

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The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 95-101页

作者： LIU yuan-ni LI Xin CHEN shan-zhi QIN Zhen State key Lab of Switching and Networking Technology Beijing University of Posts and Telecommunications Beijing 100876 China State key Lab of W1reless Mobile Communication China Academy of Telecommunication Technology Beijing 100083 China School of Lifesciences and Technology Xidian University Xi＇an 710126 China

Cascading failures are common in most of the networks, where traffic is rerouted to bypass malfunctioning routers, eventually leading to an avalanche of overloads on other routers that are not equipped to handle extra traffic, which can result in a congestion regime with degradation in the network performance. In order to investigate how a small shock can trigger avalanches mechanisms affecting a considerable fraction of the network, lots of failure models have been constructed, but they have focused only on the static properties of the network that can not reflect the performance affected by the avalanche exactly. In this paper, we proposed a simple model for cascading failures in the network to explore how the failures can have a great impact on the network performance, and we allocated every node a capacity by tolerance parameter based on the node importance, which is determined by node degree, the number of the shortest paths through a node, and the number of the shortest paths through the neighbors of a node, then we fixed every element a weight to compute the node importance by analytic hierarchy process （AHP） theory. Based on our model, we analyzed the influence of different types of attacks to the network performance, and also tabled some proposals for reducing the damage that the networks suffered from the cascading failures.

关键词： cascading failure power-law tolerance parameter network efficiency

Whole-Brain Monosynaptic Inputs to Hypoglossal Motor Neurons in Mice

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Neuroscience Bulletin 2020年第6期36卷 585-597页

作者： Han Guo Xiang-shan yuan Ji-Chuan Zhou Hui Chen shan-Qun Li Wei-Min Qu Zhi-Li Huang Department of Pharmacology School of Basic Medical SciencesState Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceInstitutes of Brain ScienceFudan UniversityShanghai 200032China Department of Anatomy School of Basic Medical SciencesFudan UniversityShanghai 200032China Department of Pulmonary Medicine Zhongshan HospitalFudan UniversityShanghai 200032China

Hypoglossal motor neurons(HMNs) innervate tongue muscles and play key roles in a variety of physiological functions,including swallowing,mastication,suckling,vocalization,and *** of HMNs is associated with several diseases,such as obstructive sleep apnea(OSA) and sudden infant death *** A is a serious breathing disorder associated with the activity of HMNs during different sleep-wake *** the neural mechanisms by which the statedependent activities of HMNs are controlled may be helpful in providing a theoretical basis for effective therapy for ***,the presynaptic partners governing the activity of HMNs remain to be *** the present study,we used a cell-type-specific retrograde tracing system based on a modified rabies virus along with a Cre/loxP gene-expression strategy to map the whole-brain monosynaptic inputs to HMNs in *** identified 53 nuclei targeting HMNs from six brain regions:the amygdala,hypothalamus,midbrain,pons,medulla,and *** discovered that GAB Aergic neurons in the central amygdaloid nucleus,as well as calretinin neurons in the parasubthalamic nucleus,sent monosynaptic projections to *** addition,HMNs received direct inputs from several regions associated with respiration,such as the preBotzinger complex,parabrachial nucleus,nucleus of the solitary tract,and *** regions engaged in sleep-wake regulation(the parafacial zone,parabrachial nucleus,ventral medulla,sublaterodorsal tegmental nucleus,dorsal raphe nucleus,periaqueductal gray,and hypothalamus) also provided primary inputs to *** results contribute to further elucidating the neural circuits underlying disorders caused by the dysfunction of HMNs.

关键词： Hypoglossal motor neuron Monosynaptic input Rabies virus Respiration Sleep and wake

Microstructure evolution and improved properties of laminated titanium matrix composites with gradient equiaxed grains

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Science China(Technological Sciences) 2020年第12期63卷 2687-2697页

作者： WANG Shuai HUANG LuJun JIANG shan ZHANG Rui AN Qi SUN yuan GENG Lin School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

With the purpose of improving both the strength and ductility,gradient equiaxed grains were successfully achieved in the matrix of the laminated TiB/Ti-TiB/Ti-6.58Al-1.76Zr-1.04V-0.89Mo composite via water quenching(WQ) and thermal compressing deformation. Gradient equiaxed grains varied from approximately 1.0 μm in TiB/Ti-6.58Al-1.76Zr-1.04V-0.89Mo layer to 5.5 μm in TiB/Ti layer. The formation of the gradient structure was related to the alloying elements diffusion during the initial sintering process,and the equiaxed shape was constructed by dynamic recrystallization during thermal compressing. WQ treatment before thermal compressing was adopted to obtain fine lamellar structure,which promoted the segmentation of αlamellae,and accelerated the dynamic recrystallization process. Raising the quenching temperature can increase the proportion of equiaxed grains in the composite,which improved both the bending strength and ductility. Compared with the as-sintered specimen,the specimen with gradient equiaxed grains exhibited nearly 30% enhancement in flexural strength(from 1719 to 2218 MPa),and the ultimate bending fracture strain was increased from 7.0% to 17.2%. This significant improvement should be attributed to the coordination deformation by interface gradient grains,the grain refinement strengthening and the good balance between strength and ductility of the recrystallized equiaxed grains.

关键词： titanium matrix composites laminated structure gradient equiaxed grains microstructure evolution dynamic recrystallization bending properties

Continuous synthesis of ultra-fine fiber for wearable mechanoluminescent textile

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Nano Research 2023年第7期16卷 9379-9386页

作者： Shulong Chang yuan Deng Na Li Lijun Wang Chong-Xin shan Lin Dong Key Laboratory of Material Physics Ministry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Continuous mechanoluminescence(ML)fibers and fiber-woven textiles have the potential to serve as new wearable devices for sensors,healthcare,human-computer interfacing,and Internet of *** the demands on wearability and adaptability for the ML textiles,it is essential to realize the continuous synthesis of fiber,while maintaining a desired small ***,we develop a novel adhere-coating method to fabricate ML composite fiber,consisting of a thin polyurethane(PU)core and ZnS:Cu/polydimethylsiloxane(PDMS)shell,with the outer diameter of 120μ*** diluting PDMS to tune the thickness of liquid coating layer,droplets formation has been effectively *** composite fiber exhibits a smooth surface structure and superior ML performances,including high brightness,excellent flexibility,and *** addition,a weft knitting textile fabricated by the continuous ML fiber can be easily delighted by manually stretching,and the ML fibers can emit visible signals upon human motion stimuli when woven into commercial *** continuous ultra-fine ML fibers are promising as wearable sensing devices for human motion detection and human-machine interactions.

关键词： mechanoluminescence fiber continuous synthesis wearable textile