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Spatiotemporal evolution of land transportation networks and accessibility in inland mountainous areas 1917-2017:A case study of Southwest China

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Journal of Mountain Science 2020年第9期17卷 2262-2279页

作者： HUANG Yan zong hui-ming School of Geographical Sciences Southwest UniversityChongqing 400715China State Cultivation Base of Eco-agriculture for Southwest Mountainous Land Southwest UniversityChongqing 400715China

Located in the western hinterland,Southwest China is a typical mountainous area covered by plateaus,mountains and *** ruggedness hinders regional internal and external connections,and its poor transportation infrastructure has long constrained the socioeconomic development of Southwest *** on the GIS transportation database,this paper explored the spatiotemporal evolution and characteristics of the land transportation networks and the accessibility of Southwest China from 1917 to *** accessibility in Southwest China has significantly improved,and transportation infrastructure has gradually integrated the transportation circles of the52 central *** transportation network has followed an evolutionary process from a"hub-spoke pattern"to a"network pattern",while the construction of a high-speed railway(HSR)has brought about significant spatial *** argue that innovation in transportation technology is one of the most effective factors for promoting a significant change in regional *** addition,the spatial distribution and evolution of accessibility in Southwest China presents a verticalcharacteristic that distinguishes it from the plains,as the spillover effects of new transportation infrastructure on accessibility improvement are partly offset by the mountainous ***,in Southwest China,there is significant"path dependence"in the evolution of the transportation network,since a large portion of the population is concentrated along transportation corridors in mountainous areas.

关键词： Southwest China Mountainous areas Transportation network Spatiotemporal evolution Accessibility Infrastructure

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Spectroscopic Studies of a Three-dimensional, Five-coordinated Copper(Ⅱ) Complex via Hydrogen Bonds: [Cu(PDA)(H_2O)_2](H_2PDA=Pyridine-2,6-dicarboxylic Acid)

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Chemical Research in Chinese Universities 2003年第1期19卷 6-9页

作者： WANG Wen-zhen JIANG zong-hui 等 DepartmentofChemistry NankaiUniversityTianjin300071P.R.China StateKeyLaboratoryofCoordinationChemistry NanjingUniversityNanjijing210093P.R.China

A new copper(Ⅱ) complex [Cu(PDA)(H 2O) 2] was synthesized and its structure was determined. Cu(Ⅱ) is five coordinated in a tetragonal pyramid geometry. The two coordinating water molecules are different and the two Cu-O bond lengths differ by nearly 0.02 nm. The whole crystal is linked to form a three dimensional network by means of hydrogen bonds. The X band ESR spectrum shows three different g tensors with a well resolved hyperfine structure in the g z signal, giving the ESR parameters g x=2 05, g y =2 065 and g z =2 29. The covalency of the coordinate bonds and the deviation from tetragonal pyramid geometry for the complex are discussed based on the ESR spectra.

关键词： Crystal structure Three dimensional network ESR spectrum Tetragonal pyramid geometry Hydrogen bond π π interaction

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Analysis on hot deformation and following cooling technology of 25Cr2Ni4MoVA steel

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Journal of Iron and Steel Research International 2021年第10期28卷 1305-1314页

作者： Jie Yang zong-hui Su Feng-li Sui School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina

The true stress–true strain curves of 25Cr2Ni4MoVA steel were obtained by uniaxial compression experiments at 850–1200℃ in the strain rate range of 0.001–10.0 s^(−1).And the dynamic continuous cooling transformation curves were obtained at the cooling rate range of 0.5–15.0℃ s^(−1) from the austenitization temperature of 1000℃ to the room temperature by pre-strain of 0.2 as *** power dissipation map and the dynamic continuous cooling transformation diagram were constructed based on the data provided by these *** with the optical micrographs of the compressed samples,the full dynamic recrystallization region is located between 1000 and 1200℃ and at the strain rate range from 0.01 to 10.0 s^(−1) with the power dissipation efficiency not less than *** the full dynamic recrystallization region,the power dissipation efficiency increases and the dynamic recrystallization activation energy decreases with the temperature *** the strain rate decreasing,the power dissipation efficiency increases firstly and then starts to decrease as the strain rate is less than 0.1 s^(−1),and dynamic recrystallization activation energy changes on the *** to the dynamic continuous cooling transformation diagram,slow cooling is a better way for the hot-deformed piece with large size or complex shape to avoid cracking as the temperature of the piece is lower than 400℃,and different cooling ways can be used for the hot-deformed piece with small size and simple shapes to obtain certain microstructure and meet good compressive properties.

关键词： 25Cr2Ni4MoVA steel Power dissipation map Dynamic continuous cooling transformation diagram Hot deformation Cooling rate

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无线时间敏感网络技术综述

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软件学报 2025年第1期36卷 184-202页

作者：乔萱李宗辉刘强艾渤万海邓仰东北京交通大学计算机与信息技术学院北京交通大学电子信息工程学院清华大学软件学院

由IEEE 802.1任务组开发的时间敏感网络标准可以用来构建高可靠、低延迟、低抖动的以太网,将时间敏感网络扩展到无线领域也是目前许多工作的研究重点.与传统的有线通信相比,无线的时间敏感网络不仅可以实现高可靠和低时延通信,还具有更... 详细信息

由IEEE 802.1任务组开发的时间敏感网络标准可以用来构建高可靠、低延迟、低抖动的以太网,将时间敏感网络扩展到无线领域也是目前许多工作的研究重点.与传统的有线通信相比,无线的时间敏感网络不仅可以实现高可靠和低时延通信,还具有更高的灵活性、更强的移动性以及更低的布线和维护成本等优点.因此,在面对未来无人驾驶、协作机器人、远程医疗控制等新兴应用时,无线时间敏感网络被认为是一种十分有前景的技术.无线网络一般可以分为基于基础设施的无线网络和无基础设施的无线网络,而后者基于移动性还可以分为两类:移动自组织网络和无线传感网络,因此主要从这3种网络类型出发,对其应用场景、相关技术、路由协议以及高可靠低时延传输进行了调研与综述.

关键词：时间敏感网络 5G 移动自组织网络无线传感网络

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IMPULP:A Hardware Approach for In-Process Memory Protection via User-Level Partitioning

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Journal of Computer Science & Technology 2020年第2期35卷 418-432页

作者： Yang-Yang Zhao Ming-Yu Chen Yu-Hang Liu zong-Hao Yang Xiao-Jing Zhu zong-hui Hong Yun-Ge Guo State Key Laboratory of Computer Architecture Institute of Computing TechnologyChinese Academy of Sciences Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China Peng Cheng Laboratory Shenzhen 518055China

In recent years many security attacks occur when malicious codes abuse in-process memory *** to the increasing complexity,an application program may call third-party code which cannot be controlled by programmers but may contain security *** a result,the users have the risk of suffering information leakage and control flow ***,current solutions like Intel memory protection extensions(MPX)severely degrade performance,while other approaches like Intel memory protection keys(MPK)lack flexibility in dividing security *** this paper,we propose IMPULP,an effective and efficient hardware approach for in-process memory *** rationale of IMPULP is user-level partitioning that user code segments are divided into different security domains according to their instruction addresses,and accessible memory spaces are specified dynamically for each domain via a set of boundary *** instruction related to memory access will be checked according to its security domain and the corresponding boundaries,and illegal in-process memory access of untrusted code segments will be *** can be leveraged to prevent a wide range of in-process memory abuse attacks,such as buffer overflows and memory *** verification,an FPGA prototype based on RISC-V instruction set architecture has been *** present eight tests to verify the effectiveness of IMPULP,including five memory protection function tests,a test to defense typical buffer overflow,a test to defense famous memory leakage attack named Heartbleed,and a test for security *** execute the SPEC CPU2006 benchmark programs to evaluate the efficiency of *** performance overhead of IMPULP is less than 0.2%runtime on average,which is ***,the resource overhead is less than 5.5%for hardware modification of IMPULP.

关键词： in-process isolation memory protection out-of-bounds user-level partitioning

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A social tag clustering method based on common co-occurrence group similarity

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Frontiers of Information Technology & Electronic Engineering 2016年第2期17卷 122-134页

作者： hui-zong LI Xue-gang HU Yao-jin LIN Wei HE Jian-han PAN School of Computer and Information Hefei University of Technology School of Economics and Management Anhui University of Science and Technology School of Computer Minnan Normal University

Social tagging systems are widely applied in Web *** users use these systems to create,organize,manage,and share Internet resources ***,many ambiguous and uncontrolled tags produced by social tagging systems not only worsen users' experience,but also restrict resources' retrieval *** clustering can aggregate tags with similar semantics together,and help mitigate the above *** this paper,we first present a common co-occurrence group similarity based approach,which employs the ternary relation among users,resources,and tags to measure the semantic relevance between *** we propose a spectral clustering method to address the high dimensionality and sparsity of the annotating ***,experimental results show that the proposed method is useful and efficient.

关键词： Social tagging systems Tag co-occurrence Spectral clustering Group similarity

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Effects of thermomechanical treatments on the microstructures and mechanical properties of GTA-welded AZ31B magnesium alloy

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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 945-950页

作者： Ya-jie Chu Jian Chen Xiao-quan Li Shen-qing WU zong-hui Yang Department of Material Science and Engineering Jiangsu Key Laboratory for Advanced Metallic Materials South East University Nanjing 211189 china Department of Material Engineering Nanjing Institute of Technology Nanjing 211167 China

Thermomechanical treatments were carried out to improve the properties of AZ31B joints prepared by gas tungsten arc welding. The microstructures of the joints were studied by optical microscopy and scanning electron microscopy with energy-dispersive spectrometry. Tensile tests and hardness tests were performed to investigate the effects of thermomechanical treatments on the mechanical properties of the joints. It is found that the thermomechanical-treated joints show superior mechanical properties against the as-welded joints, and their ultimate tensile strength can reach more than 92% of the base material. This mainly attributes to the formation of fine equiaxed grains in the fusion zone. ARer thermomechanical treatments the dendrites are transformed to fine spherical grains, and the dendritic segregation can be effectively eliminated.

关键词： magnesium alloys welding microstructure mechanical properties fractography

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Computed tomography perfusion imaging evaluation of angiogenesis in patients with pancreatic adenocarcinoma

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World Journal of Clinical Cases 2022年第8期10卷 2393-2403页

作者： Wen Liu Bo Yin zong-hui Liang Yang Yu Na Lu Department of Radiology Jinshan HospitalFudan UniversityShanghai 201508China Department of Radiology Huashan HospitalFudan UniversityShanghai 200000China Department of Radiology Huashan Hospital NorthFudan UniversityShanghai 200000China Department of Radiology Shanghai Jing’an District Central HospitalHuashan Hospital Jing’an BranchFudan UniversityShanghai 200000China

BACKGROUND Pancreatic adenocarcinoma is one of the most common malignant tumors of the digestive *** than 80%of patients with pancreatic adenocarcinoma are not diagnosed until late stage and have distant or local *** To investigate the value of computed tomography(CT)perfusion imaging in the evaluation of angiogenesis in pancreatic adenocarcinoma *** This is a retrospective cohort *** with pancreatic adenocarcinoma and volunteers without pancreatic diseases underwent CT perfusion imaging from December 2014 to August 2017 in Huashan Hospital,Fudan University Shanghai,*** A total number of 35 pancreatic adenocarcinoma patients and 33 volunteers were *** relative blood flow(r BF),and relative blood volume(r BV)were significantly lower in patients with pancreatic adenocarcinoma than in the control group(P<0.05).Conversely,the relative permeability in patients with pancreatic adenocarcinoma was significantly higher than that in controls(P<0.05).In addition,r BF,r BV,and the vascular maturity index(VMI)were significantly lower in gradeⅢ-Ⅳpancreatic adenocarcinoma than in gradeⅠ-Ⅱpancreatic adenocarcinoma(P<0.05).Vascular endothelial growth factor(VEGF),CD105-MVD,CD34-MVD,and angiogenesis rate(AR)were significantly higher in gradeⅢ-Ⅳpancreatic adenocarcinoma than in gradeⅠ-Ⅱpancreatic adenocarcinoma(P<0.05).Significant correlations between r BF and VEGF,CD105-MVD,AR,and VMI(P<0.01)were ***,the levels of r BV were statistically significantly correlated with those of VEGF,CD105-MVD,CD34-MVD,and VMI(P<0.01).CONCLUSION Perfusion CT imaging may be an appropriate approach for quantitative assessment of tumor angiogenesis in pancreatic adenocarcinoma.

关键词： Pancreatic adenocarcinoma Perfusion computed tomography Angiogenesis Evaluation Imaging Quantitative assessment

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Avanafil for male erectile dysfunction： a systematic review and meta-analysis

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Asian Journal of Andrology 2014年第3期16卷 472-477页

作者： Yuan-Shan Cui Nan Li Huan-Tao zong hui-Lei Yan Yong Zhang Department of Urology Beijing Tian-Tan Hospital Capital Medical University Beijing China

Avanafil, a potent new selective phosphodiesterase type 5 （PDE5） inhibitor, has been developed for the treatment of erectile dysfunction （ED）. We carried out a systematic review and meta-analysis to assess the efficacy and safety of this drug for the treatment of ED. A literature review was performed to identify all published randomized, double-blind, placebo-controlled trials of avanafil for the treatment of ED. The search included the following databases： MEDLINE, EMBASE and the Cochrane Controlled Trials Register. The reference lists of the retrieved studies were also investigated. Four publications, involving a total of 1381 patients, were used in the analysis, including four randomized controlled trials （RCTs） that compared avanafU with a placebo. Among the co-primary efficacy end points indicating that avanafil 100 mg was more effective than a placebo were successful vaginal penetration （SEP2）（the odds ratio （OR） =5.06, 95% confidence interval （CI） =3.29-7.78, P〈 0.00001） and successful intercourse （SEP3）（OR = 3.99, 95% CI = 2.80-5.67, P 〈 0.00001）. Men randomized to receive avanafil were less likely than those receiving the placebo to drop out due to an adverse event （AE）（OR = 1.48, 95% CI = 0.54-4.08, P = 0.44）. Specific AEs with avanafil included headache and flushing, which were significantly less likely to occur with placebo. This meta-analysis indicates that avanafil 100 or 200 mg is an effective and well-tolerated treatment for ED. Compared with avanafil 100 mg, patients who take avanafil 200 mg are more likely to experience headaches.

关键词： avanafil erectile dysfunction meta-analysis randomized controlled trial

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Salicyaldehyde-based fluorescent sensors with high sensitivity for amino acids

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Chinese Chemical Letters 2011年第8期22卷 985-988页

作者： Xi Huai Qiang Zhi hui Gao Xue Chuan Wang Jian Zheng Li hui zong Chi Min Du Shaanxi University of Science and Technology Xian 710021 China Beijing Fanbo Biochemical Company Beijing 100000 China

Structurally simple salicylaldehyde-based fluoreseent sensors for amino acids have been obtained by one-step or two-step *** sensors show significant fluorescence enhancement in the presence of many amino acids at concentrations as low as 10~5 mol/*** reversible reaction of the aldehydes with amino acids to form imines in aqueous solution is proposed to account for the observed fluorescence enhancement.

关键词： Amino acids Fluorescent sensors Simple Highly sensitive

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