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Building a next generation Internet with source address validation architecture

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science in china(Series F) 2008年第11期51卷 1681-1691页

作者： WU JianPing1,3,REN Gang1,3 & LI Xing2,3 1 Department of Computer science,Tsinghua University,beijing 100084,china 2 Department of Electronic Engineering,Tsinghua University,beijing 100084,china 3 Tsinghua national Laboratory for Information science and Technology(TNList) ,beijing 100084,china Department of Computer science Tsinghua University Department of Electronic Engineering Tsinghua University Tsinghua national Laboratory for Information science and Technology (TNList)

The IP packet forwarding of current Internet is mainly destination based. In the forwarding process, the source IP address is not checked in most *** causes serious security, management and accounting problems. Based on the drastically increased IPv6 address space, a ＂source address validation architecture＂（SAVA） is proposed in this paper, which can guarantee that every packet received and forwarded holds an authenticated source IP address. The design goals of the architecture are lightweight, loose coupling, ＂multi-fence support＂ and incremental deployment. This paper discusses the design and implementation for the architecture, including inter-AS, intra-AS and local subnet. The performance and scalability of SAVA are described. This architecture is deployed into the CNGI-CERNET2 infrastructure a large-scale native IPv6 backbone network of the china Next Generation Internet project. We believe that the SAVA will help the transition to a new, more secure and dependable Internet.

关键词： IP source address validation network architecture network security

Association between ICU quality and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality improvement action(EQIA)study:a national cohort study in china from 2017 to 2019

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Frontiers of Medicine 2024年第2期18卷 315-326页

作者： Wei Cheng Jieqing Chen Xudong Ma Jialu Sun Sifa Gao Ye Wang Longxiang Su Lu Wang Wei Du Huaiwu He Yujie Chen Zunzhu Li Qi Li Jianhua Sun Hongbo Luo Jinbang Liu Guangliang Shan Bing Du Yanhong Guo Dawei Liu Chang Yin Xiang Zhou on behalf of the china national Critical Care Quality Control Center-the ECMO quality improvement action(EQIA)study Department of Critical Care Medicine State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing100730China Information Center Department/Department of Information Management State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalPeking Union Medical College&Chinese Academy of Medical SciencesBeijing100730China Department of Medical Administration National Health Commission of the People’s Republic of ChinaBeijing100044China School of Population Medicine and Public Health Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100730China Department of Epidemiology and Biostatistics Institute of Basic Medicine SciencesChinese Academy of Medical Sciences(CAMS)&School of Basic MedicinePeking Union Medical CollegeBeijing100730China national Institute of Hospital Administration National Health Commission of the People’s Republic of ChinaBeijing100044China 不详

This cohort study was performed to explore the influence of intensive care unit(ICU)quality on in-hospital mortality of veno-venous(V-V)extracorporeal membrane oxygenation(ECMO)-supported patients in *** study involved all V-V ECMO-supported patients in 318 of 1700 tertiary hospitals from 2017 to 2019,using data from the national Clinical Improvement System and china national Critical Care Quality Control *** quality was assessed by quality control indicators and capacity *** the 2563 V-V ECMO-supported patients in 318 hospitals,a significant correlation was found between ECMO-related complications and *** reintubation rate within 48 hours after extubation and the total ICU mortality rate were independent risk factors for higher in-hospital mortality of V-V ECMO-supported patients(cutoff:1.5%and 7.0%;95%confidence interval:1.05–1.48 and 1.04–1.45;odds ratios:1.25 and 1.23;P=0.012 and P=0.015,respectively).Meanwhile,the V-V ECMO center volume was a protective factor(cutoff of≥50 cases within the 3-year study period;95%confidence interval:0.57–0.83,odds ratio:0.69,P=0.0001).The subgroup analysis of 864 patients in 11 high-volume centers further strengthened these ***,ICU quality may play an important role in improving the prognosis of V-V ECMO-supported patients.

关键词： veno-venous extracorporeal membrane oxygenation in-hospital mortality high-volume centers quality control intensive care unit capacity parameters

Influence of Ru addition on microstructure and stress-rupture property of Ni-based single crystal superalloys

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Progress in natural science:Materials International 2010年第1期20卷 61-69页

作者： Jing-yang CHEN~1,Qiang FENG~(1,2),La-mei CAO~3,Zu-qing SUN~1 1.State Key Laboratory for Advanced Metals and Materials,University of science and Technology beijing, beijing 100083,china 2.national Center for Materials Service Safety,University of science and Technology beijing,beijing 100083,china 3.national Key Laboratory of science and Technology on Advanced High Temperature Structural Materials, beijing Institute of Aeronautical Materials,beijing 100095,china State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing national Center for Materials Service Safety University of Science and Technology Beijing national Key Laboratory of science and Technology on Advanced

The effects of Ru on the microstructure and stress-rupture property were investigated in two experimental Ni-based single crystal superalloys with and without Ru addition(5.1%,mass fraction).The results indicate that the morphology ofγ' precipitates in the dendrite core and interdendritic region are intermediate and nearly spherical,respectively,in the Ru-free alloy after being aged at 1100℃for 8 *** Re partitioning ratio increases due to Ru addition and Ru partitioned preferentially to theγphase in both dendrite core and interdendritic region of the Ru-containing alloy,which results in more negative lattice misfit and more cuboidalγ' ***,theγ' volume fraction increases while the precipitate size and y channel width decreases due to Ru addition in both dendrite core and interdendritic *** addition improves the stress-rupture life at 1100℃/140 MPa significantly due to higherγ' volume fraction,more negative lattice misfit and a well rafting structure as well as lessγchannel width.

关键词： Ni-based superalloys ruthenium elemental partitioning ratio lattice misfit γ’ morphology stress-rupture property

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science china(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2, LIU GuoQuan2, LI ZhiLin3, FENG ChengMing1 1 Mechanical and Electronic Engineering College, Shandong Agricultural University, Tai’an 271018, china 2 College of Materials science and Engineering, University of science and Technology, beijing 100083, china 3 College of Material science and Engineering, beijing University of Chemical Technology, beijing 100029, china Mechanical and Electronic Engineering College Shandong Agricultural UniversityTai'an 271018China College of Materials science and Engineering University of Science and TechnologyBeijing 100083China College of Material science and Engineering Beij

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

An efficient quantum secret sharing protocol with orthogonal product states

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science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2, WEN QiaoYan3 & ZHU FuChen4 1 School of Computer, beijing University of Technology, beijing 100022, china 2 State Key Laboratory of Information Security, Graduate University of Chinese Academy of sciences, beijing 100022, china 3 School of science, beijing University of Posts and Telecommunications, beijing 100876, china 4 national Key Laboratory for Modern Communications, Chengdu 610041, china School of Computer Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China School of science Beijing University of Posts and Telecommunications Beijing China national Key Laboratory for Modern Communications Chengdu China

An efficient quantum secret sharing protocol with orthogonal product states in the 33 Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

Wave mechanics in quantum phase space: hydrogen atom

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Progress in natural science:Materials International 2007年第2期17卷 144-149页

作者： LU Jun ( Department of foundational science, beijing Union University, beijing 100101, china Department of Computational science, national University of Singapore, Singapore 117543, Singapore) Department of foundational science Beijing Union University Beijing 100101 China. Department of Computational science National University of Singapore Singapore 117543 Singapore

The rigorous solutions of the stationary Schrodinger equation for hydrogen atom are solved with the wave-mechanics method within the framework of the quantum phase-space representation established by Torres-Vega and Frederick. The "Fourier-like" projection transformations of wave function from the phase space to position and momentum spaces are extended to three-dimensional systems. The eigenfunctions in general position and momentum spaces could be obtained through the transformations from eigenfunction in the phase space.

关键词： quantum phase space hydrogen atom projection transformation.

Fusion tracking in color and infrared images using joint sparse representation

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science china(Information sciences) 2012年第3期55卷 590-599页

作者： LIU HuaPing1,2,3 & SUN FuChun1,2,3 1Department of Computer science and Technology, Tsinghua University, beijing 100084, china 2State Key Laboratory of Intelligent Technology and Systems, beijing 100084, china 3Tsinghua national Laboratory for Information science and Technology, beijing 100084, china Department of Computer science and Technology Tsinghua University State Key Laboratory of Intelligent Technology and Systems Tsinghua national Laboratory for Information science and Technology

Currently sparse signal reconstruction gains considerable interest and is applied in many fields. In this paper, a similarity induced by joint sparse representation is designed to construct the likelihood function of particle filter tracker so that the color visual spectrum and thermal spectrum images can be fused for object tracking. The proposed fusion scheme performs joint sparse representation calculation on both modalities and the resultant tracking results are fused using min operation on the sparse representation coefficients. In addition, a co-learning approach is proposed to update the reference templates of both modality and enhance the tracking robustness. The proposed fusion scheme outperforms state-of-the-art approaches, and its effectiveness is verified using OTCBVS database.

关键词： joint sparse representation fusion tracking color image infrared image

Ecological hydrograph based on Schizothorax chongi habitat conservation in the dewatered river channel between Jinping cascaded dams

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science china(Technological sciences) 2011年第S1期54卷 54-63页

作者： LI RuoNan 1,CHEN QiuWen 1,2 & Duan Chen 1,3 1 Research Center for Eco-environmental science,Chinese Academy of sciences,beijing 100085,china 2 china Three Gorges University,Yichang 443002,china 3 Hydraulics Department,Changjiang River Scientific Research Institute,Wuhan 430010,china Research Center for Eco-environmental science Chinese Academy of Sciences china Three Gorges University Hydraulics Department Changjiang River Scientific Research Institute

Hydropower development changes the river hydrological regime,thereby altering river ecosystem *** important measure for reducing degradation of ecosystem is to determine ecological flow and implement it by reservoir *** paper described a method to calculate river ecological flow based on fish habitat conservation and applied it to Jinping River Bend of Yalong *** chongi was selected as target species,and the fish habitat model coupling with water environmental model was developed according to the relationship between fish and water environment ***,improved hydraulic habitat suitability index(IHHS) and habitat fragment index(HFI) varying with discharge were discussed in this *** area representing average annual flow was taken as a reference,and then ecological hydrographs under different habitat conservation levels were calculated considering season variation and life stages of *** to the natural condition,the model results indicated that the reservoir operation clearly influenced the habitat of the target *** was proposed to ensure flow releases to maintain 70%-90% habitat in section after joint while about 60% before joint.

关键词： river habitat habitat assessment ecological flow ecological hydrograph

Distribution of Nb atom in the TiAl+Nb system

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Rare Metals 2001年第1期20卷 5-12页

作者： Xiaodong Ni, Xidong Hui, Guoliang Chen (Applied science School, University of science and Technology beijing, beijing 100083, china State Key Laboratory for Advanced Metals and Materials, University of science and Technology beijing, china) Appl. Sci. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on MEAM (the modified embedded atom method) potential and an average atom model similar to B-W (Bragg-Williams) method, the distribution of Nb atoms in TiAl+Nb compounds with various composition was calculated. The calculation results showed that Nb atoms prefer to occupy the Ti sublattice of L10 structure for all compounds in question. With increasing atomic fraction of Nb and Al, Nb atoms exhibited a trend of ordered distribution on the Ti sublattice and result in a new L10 derivative superlattice structure.

关键词： Computer simulation Intermetallics Superlattices Ternary systems