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The Research on Handoff Strategy in Beyond 3G Wireless Networks

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 26-30页

作者： CUI Hong-yan TIAN Hui XU hai-bo zhang ping College of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

One of the major challenges for beyond third generation mobile .systems is efficient mobility management. This paper proposes a distributed dynamic management .scheme of handoff based on B3G networks. This scheme can reduce the cost of update signalling and transmitting packets, and improve the system capability. In this scheme, the dynamic building network approach is adopted to deduce the update signalling cost. We implement the distributed dynamic management scheme of handoff in a simulation platform and compare its performance with that of general centralized handoff management schemes. Our simulation results indicate that our scheme is capable of reducing the update handoff latency, and enhancing the performance.

关键词： B3G IPv6 handoff AP CA

Mechanical and tribological properties of graphene nanoplatelets-reinforced titanium composites fabricated by powder metallurgy

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Journal of Iron and Steel Research International 2020年第11期27卷 1357-1362页

作者： Zhen Cao Jiong-li Li hai-ping zhang Wen-bo Li Xu-dong Wang AECC Beijing Institute of Aeronautical Materials Beijing 100095China Beijing Institute of Graphene Technology Beijing 100094China Beijing Engineering Research Centre of Graphene Application Beijing 100095China

Titanium matrix composite reinforced by graphene nanoplatelets(GNPs)was fabricated via powder metallurgy *** isostatic pressing and hot extrusion were used to consolidate the mixed powder of GNPs and TC4 titanium(Ti)*** microstructures,mechanical properties and sliding wear performance of Ti/GNPs composite had been researched to evaluate the rein forcing effect of GNPs on tita nium *** observation indicates that GNPs could restrain grai n growth slightly in titanium *** matrix and graphene exhibit a clean and firm interface formed by means of metallurgical bonding on atomic *** with the monolithic titanium alloy,the composite with 1.2 vol.%GNPs exhibits significantly improved elastic modulus and *** sliding wear test shows that there is an obvious enhancement in the tribological performance of Ti/GNPs composite with 1.2 vol.%*** results of this work indicate that GNP is an efficient reinforcenient material in titanium *** strengthening mechanism including precipitates strengthening,load transfer and grain refinement mechanism of GNPs in titanium matrix was discussed.A modified shear-lag model was used to analyze the reinforcement contribution of the stress transfer *** calculation shows that the stress load mechanism constitutes the main strengthening mechanism in Ti/GNPs composite.

关键词： Titanium matrix composite Graphene Mechanical testing Tribological property Powder metallurgy

Plasma free amino acid profiling of esophageal cancer using high-performance liquid chromatography spectroscopy

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World Journal of Gastroenterology 2014年第26期20卷 8653-8659页

作者： Hong Ma Ayshamgul Hasim Batur Mamtimin Bin Kong hai-ping zhang Ilyar Sheyhidin Department of Thoracic Surgery The First Affiliated HospitalMedical University of Xinjiang Department of Pathology College of Basic MedicineMedical University of Xinjiang Centers of Pharmaceutical Analysis College of PharmacyMedical University of Xinjiang Pharmacy Department of Production and Construction Corps General Hospital of Xinjiang

AIM: To perform plasma free amino acid (PFAA) profiling of esophageal squamous cell carcinoma (ESCC) patients at different pathological stages and healthy subjects.

关键词： Metabolomics High-performance liquid chromatography Esophageal squamous cell cancer Plasma Amino acids

Microsatellite alterations in phenotypically normal esophageal squamous epithelium and metaplasia-dysplasia-adenocarcinoma sequence

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World Journal of Gastroenterology 2008年第25期14卷 4070-4076页

作者： Jian-Chun Cai Di Liu Kai-Hua Liu hai-ping zhang Shan Zhong Ning-Sao Xia Department of Oncology Surgery Xiamen Cancer Center Affiliated Xiamen First Hospital Fujian Medical University Xiamen 361003 Fujian Province China Department of Material Science andEngineering Chemistry and Chemical Engineering CollegeXiamen University Xiamen 361005 Fujian Province China National Institute of Diagnostics and VaccineDevelopment in Infectious Diseases Xiamen UniversityXiamen 361005 Fujian Province China

AIM: To investigate the microsatellite alterations in phenotypically normal esophageal squamous epithelium and metaplasia-dysplasia-adenocarcinoma sequence. METHODS: Forty-one specimens were obtained from esophageal cancer (EC) patients. Histopathological assessment identified 23 squamous cell carcinomas (SCC) and 18 adenocarcinomas (ADC), including only 8 ADC with Barrett esophageal columnar epithelium (metaplasia) and dysplasia adjacent to ADC. Paraffin-embedded normal squamous epithelium, Barrett esophageal columnar epithelium (metaplasia), dysplasia and esophageal tumor tissues were dissected from the surrounding tissues under microscopic guidance. DNA was extracted using proteinase K digestion buffer, and DNA was diluted at 1:100, 1:1000, 1:5000, 1:10 000 and 1:50 000, respectively. Seven microsatellite markers (D2S123, D3S1616, D3S1300, D5S346, D17S787, D18S58 and BATRII loci) were used in this study. Un-dilution and dilution polymerase chainreactions (PCR) were performed, and microsatellite analysis was carried out. RESULTS: No statistically significant difference was found in microsatellite instability (MSI) and loss of heterozygosity (LOH) of un-diluted DNA between SCC and ADC. The levels of MSI and LOH were high in the metaplasia-dysplasia-adenocarcinoma sequence of diluted DNA. The more the diluted DNA was, the higher the rates of MSI and LOH were at the above 7 loci, especially at D3S1616, D5S346, D2S123, D3S1300 and D18S58 loci. CONCLUSION: The sequence of metaplasia-dysplasia-adenocarcinoma is associated with microsatellite alterations, including MSI and LOH. The MSI and LOH may be the early genetic events during esophageal carcinogenesis, and genetic alterations at the D3S1616, D5S346 and D3S123 loci may play a role in the progress of microsatellite alterations.

关键词： Microsatellite alterlaons Dilution PCR Metaplasia-dysplasia-adenocarcinoma sequence Esophageal squamous epithelium Squamous cellcarcinoma

Fluoxetine is Neuroprotective in Early Brain Injury via its Antiinflammatory and Anti-apoptotic Effects in a Rat Experimental Subarachnoid Hemorrhage Model

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Neuroscience Bulletin 2018年第6期34卷 951-962页

作者： Hui-Min Hu Bin Li Xiao-Dong Wang Yun-Shan Guo Hua Hui hai-ping zhang Biao Wang Da-Geng Huang Ding-Jun Hao Department of Spine Surgery Honghui Hospital Xi'an Jiaotong University College of Medicine Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education) Northwest University

Fluoxetine, an anti-depressant drug, has recently been shown to provide neuroprotection in central nervous system injury, but its roles in subarachnoid hemorrhage(SAH) remain unclear. In this study, we aimed to evaluate whether fluoxetine attenuates early brain injury(EBI) after SAH. We demonstrated that intraperitoneal injection of fluoxetine(10 mg/kg per day) significantly attenuated brain edema and blood-brain barrier(BBB) disruption, microglial activation, and neuronal apoptosis in EBI after experimental SAH, as evidenced by the reduction of brain water content and Evans blue dye extravasation, prevention of disruption of the tight junction proteins zonula occludens-1, claudin-5, and occludin, a decrease of cells staining positive for Iba-1, ED-1, and TUNEL and a decline in IL-1 b, IL-6, TNF-a, MDA, 3-nitrotyrosine, and 8-OHDG levels. Moreover, fluoxetine significantly improved the neurological deficits of EBI and long-term sensorimotor behavioral deficits following SAH in a rat model. These results indicated that fluoxetine has a neuroprotective effect after experimental SAH.

关键词： Subarachnoid hemorrhage Fluoxetine Blood-brain barrier Microglial activation Neuronal apoptosis

Existence of a-Cores for Games Without Compact Assumptions

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Journal of the Operations Research Society of China 2024年第2期12卷 520-527页

作者： hai-Qun zhang School of International Economics and Trade Shanghai Lixin University of Accounting and Fin Shanghai201209China

Following the representation of Kajii(J Econ Theory 56:194-205,1992),we provide some existence theorems ofα-cores for games without ordered preferences and compact *** applications,we obtain some existence results of... 详细信息

关键词： α-Core Existence Preference Noncompactness

Bi-Frobenius Algebra Structures on Quantum Complete Intersections

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1481-1504页

作者： hai JIN Pu zhang School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240P.R.China

This paper is to look for bi-Frobenius algebra structures on quantum complete intersections over field *** find a class of comultiplications,such that if√−1∈k,then a quantum complete intersection becomes a bi-Frobenius algebra with comultiplication of this form if and only if all the parameters qij=±***,it is proved that if√−1∈k then a quantum exterior algebra in two variables admits a bi-Frobenius algebra structure if and only if the parameter q=±√*** if−1/∈k,then the exterior algebra with two variables admits no bi-Frobenius algebra *** prove that the quantum complete intersections admit a bialgebra structure if and only if it admits a Hopf algebra structure,if and only if it is commutative,the characteristic of k is a prime p,and every ai a power of *** also provides a large class of examples of bi-Frobenius algebras which are not bialgebras(and hence not Hopf algebras).In commutative case,other two comultiplications on complete intersection rings are given,such that they admit non-isomorphic bi-Frobenius algebra structures.

关键词： Bi-Frobenius algebras coalgebras bialgebras Hopf algebras quantum complete intersections quantum exterior algebras

Synergy of inside doped metals–Outside coated graphene to enhance hydrogen storage in magnesium-based alloys

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Journal of Magnesium and Alloys 2024年第6期12卷 2462-2471页

作者： Kun zhang Yu Chang Jingjing Lei Jing Chen Tingzhi Si Xiaoli Ding ping Cui hai-Wen Li Qingan zhang Yongtao Li School of Materials Science and Engineering&Low-Carbon New Materials Research Center Anhui University of TechnologyMaanshanAnhui 243002China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084 Hefei General Machinery Research Institute HefeiAnhui 230031China Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials of Ministry of Education Anhui University of TechnologyMaanshan 243002China

Grain growth of magnesium(Mg)and its hydride is one of the main reasons for kinetic and capacity degradation during the hydrogen absorption and desorption *** solve this problem,herein we propose a novel method involving synergistic effect of inside embedded metals and outside coated graphene to limit the growth of Mg and its hydride *** graphene coated Mg-Y-Al alloys were selected as a model system for demonstrating this positive effect where the Mg_(91)Y_(3)Al_(6)alloy was first prepared by rapidly solidified method and then high-pressure milled with 5 wt%graphene upon 5 MPa hydrogen gas for obtaining in-situ formed YAl_(2)and YH_(3)embedded in the MgH_(2)matrix with graphene shell(denoted as MgH_(2)-Y-Al@GR).In comparison to pure MgH_(2),the obtained MgH_(2)-Y-Al@GR composites deliver much better kinetics and more stable cyclic *** instance,the MgH_(2)-Y-Al@GR can release about 6.1 wt%H_(2)within 30 min at 300℃ but pure MgH_(2)only desorbs∼1.5 wt%H_(2).The activation energy for desorption of MgH_(2)-Y-Al@GR samples is calculated to be 75.3±9.1 kJ/mol that is much lower than approximately 160 kJ/mol for pure MgH_(2).Moreover,its capacity retention is promoted from∼57%of pure MgH_(2)to∼84%after 50th cycles without obvious particle agglomeration and grain *** synergistic effect of outside graphene coating with inside embedded metals which could provide a huge number of active sites for catalysis as well as inhibit the grain growth of Mg and its hydride is believed to be responsible for these.

关键词： Energy Hydrogen storage Mg alloys Synergy effect

Preparation and properties of ZrO_(2)-strengthened porous mullite insulation materials using Y_(2)O_(3) additive

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Journal of Iron and Steel Research International 2024年第6期31卷 1514-1521页

作者： Wang-zhi Yu Yi-hong Shi ping Liu Yong-wan Wu Cheng-hao Song Xian-gong Deng Xiang Ding Song-lin Ran Yi zhang hai-jun zhang hai-liang Deng Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMa'anshan 243002AnhuiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrO_(2)-strengthened porous mullite insulation materials were prepared by foaming technology utilizing ZrSiO_(4) and Al_(2)O_(3) as primary materials and Y_(2)O_(3) as an *** effects of Y_(2)O_(3) contents on the phase composition,microstructure,mechanical properties,and heat conductivity of the porous mullite insulation materials were investigated.A suitable Y_(2)O_(3) content could promote phase transition of monoclinic ZrO_(2)(m-ZrO_(2))to tetragonal ZrO_(2)(t-ZrO_(2)),reduce pore size,and improve the strengths of as-prepared *** cold crushing strength and bending strength of as-prepared specimens with a 119µm spherical pore size using 6 wt.%Y_(2)O_(3) were 35.2 and 13.0 MPa,respectively,with a heat conductivity being only 0.248 W/(m K).

关键词： Porous mullite insulation material Zirconium oxide Y_(2)O_(3) Mechanical property Heat conductivity