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MATRIX ANALYSIS TO ADDITIVE SCHWARZ METHODS

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Journal of Computational Mathematics 1995年第4期13卷 325-336页

作者： Sun, jc Chan, TF ACAD SINICA CTR COMPBEIJING 100080PEOPLES R CHINA UNIV CALIF LOS ANGELES LOS ANGELESCA

Matrix analysis on additive Schwarz methods as preconditioners is given in this paper. Both cases of with and without coarse mesh are considered. It is pointed out that an advantage of matrix analysis is to obtain mor... 详细信息

关键词： TA MATRIX ANALYSIS TO ADDITIVE SCHWARZ METHODS BA

RUPTURE OF THIN METAL TUBES BY NORMAL AND OBLIQUE IMPACT OF BLUNT CONICALNOSED MISSILES:EXPERIMENTS

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Acta Mechanica Solida Sinica 2000年第1期13卷 67-74页

作者： Mu, jc Zhang, TG Taiyuan Univ Technol Inst Appl Mech Shanxi 030024 Peoples R China

Impact tests at both normal and oblique angles of incidence were conducted on thin mild tubes using a moderate size of 90 degrees conical-nosed missiles. The minimum impact speed that generated cracks through the thickness of the wall, termed the speed for rupture, was measured, and various modes of rupture were identified. For a thin tube hit by a missile at a normal angle of obliquity at the speed for rupture, the contact region spreads across the nose of the missile, and the transverse shear deformation is predominant in the final failure process. If the angle of obliquity is 30 degrees, the missile pierces a hole through the wall of the tube. At the speed for rupture, the kinetic energy of the missile for oblique angle 30 degrees is only about 45% that required for plugging at a normal angle of obliquity.

关键词： thin tube conical-nosed missile the speed for rupture rupture mode

Children with Disabilities and Disaster Risk Reduction: A Review

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International Journal of Disaster Risk Science 2015年第1期6卷 38-48页

作者： Steve Ronoh jc Gaillard Jay Marlowe School of Environment The University of Auckland School of Counselling Human Services and Social WorkThe University of Auckland

Children with disabilities are often excluded from disaster risk reduction(DRR) initiatives and, as a result, can experience amplified physical, psychological and educational vulnerabilities. Research on children with disabilities during disasters is lacking, and their potentia value in helping shape inclusive policies in DRR planning has been largely overlooked by both researchers and policymakers. This article highlights the existing research and knowledge gap. The review includes literature from two areas of scholarship in relation to disasters—children and people with disabilities—and provides a critique of the prevailing medical, economic, and social discourses tha conceptualize disability and associated implications for DRR. The article analyzes the different models in which disability has been conceptualized, and the role this has played in the inclusion or exclusion of children with disabilities in DRR activities and in determining access to necessary resources in the face of disaster. Finally, the study explores possible pathways to studying the contribution and involvement of children with disabilities in DRR.

关键词：有残疾的孩子残疾概念灾难风险减小危险

Climate Change’s Role in Disaster Risk Reduction’s Future:Beyond Vulnerability and Resilience

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International Journal of Disaster Risk Science 2015年第1期6卷 21-27页

作者： Ilan Kelman jc Gaillard Jessica Mercer UCL Institute for Risk and Disaster Reduction and UCL Institute for Global Health University College London Norwegian Institute of International Affairs(NUPI School of Environment The University of Auckland Secure Futures

A seminal policy year for development and sustainability occurs in 2015 due to three parallel processes that seek long-term agreements for climate change, the Sustainable Development Goals, and disaster risk *** reason exists to separate them, since all three examine and aim to deal with many similar processes, including vulnerability and resilience. This article uses vulnerability and resilience to explore the intersections and overlaps amongst climate change, disaster risk reduction, and sustainability. Critiquing concepts such as 'return to normal'and 'double exposure'demonstrate how separating climate change from wider contexts is counterproductive. Climate change is one contributor to disaster risk and one creeping environmental change amongst many, and not necessarily the most prominent or fundamental contributor. Yet climate change has become politically important, yielding an opportunity to highlight and tackle the deep-rooted vulnerability processes that cause 'multiple exposure'to multiple threats. To enhance resilience processes that deal with the challenges, a prudent place for climate changewould be as a subset within disaster risk reduction. Climate change adaptation therefore becomes one of many processes within disaster risk reduction. In turn, disaster risk reduction should sit within development and sustainability to avoid isolation from topics wider than disaster risk. Integration of the topics in this way moves beyond expressions of vulnerability and resilience towards a vision of disaster risk reduction’s future that ends tribalism and separation in order to work together to achieve common goals for humanity.

关键词：改编气候变化灾难风险减小缓解跳回危险

Positive elementary operators compressing spectrum

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Chinese Science Bulletin 1997年第4期42卷 270-274页

作者： Zhang, XL Hou, jc Department of Mathematics Shanxi Teachers University Linfen China

LET H be an infinite-dimensional complex Hilbert space with inner product and B(H) the von Neumann algebra of all bounded linear operators on H. For T∈B(H), σ(T), as usual, will denote the spectrum of T. Let Φ be a linear map from B(H) into itself. Φ is spectrum-preserving if σ(Φ(T))=σ(T) for all T∈B(H); Φ is spectrum-compressing

关键词： elementary operators spectrum preserver positive linear maps.

Synthetic Study towards Taurospongin A: Wittig Olefination Approach to the Core Structure

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Chinese Chemical Letters 2001年第11期12卷 961-964页

作者： Zheng, GR Lu, W Cai, jc Chinese Acad Sci Shanghai Inst Mat Med SIBS Shanghai 200031 Peoples R China

An efficient, convergent and enantioselective synthetic approach to the trihydroxy core structure 2 of Taurospongin A 1 is described. The featured step is a classic Wittig coupling reaction between C1-C4 aldehyde segm... 详细信息

关键词： Taurospongin A Wittig olefination enantioselective synthesis

Study on the Asymmetrical Cold Rolling of Strip under Large Width to Thickness Ratio

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Journal of Materials Science & Technology 1996年第3期12卷 232-234页

作者： Liu, HM Lian, jc Duan, ZY Yanshan University Qinhuangdao 066004 China

On the condition of the width to thickness ratio 625 of rolled strip, the asymmetrical cold strip rolling process about the width center is studied by using computer numerical simulation method and experimental method. The simulated results of the transverse distributions of the rolling pressure, the 2-directional frictions and the front and back tensions agree with the experimental results well. It is an important discovery that the rolling pressure has three peak values across the strip width on the condition of large width to thickness ratio.

关键词： Study on the Asymmetrical Cold Rolling of Strip under Large Width to Thickness Ratio

One-Pot Synthesis of N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine

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Chinese Chemical Letters 2001年第12期12卷 1061-1064页

作者： Dong, jc Li, RT Cheng, TM Peking Univ Sch Pharmaceut Sci Dept Bioorgan Chem Beijing 100083 Peoples R China

N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine 4 was synthesized from the reaction of N-Boc-pyrrolidine 1 with trimethylsilyl chloride (TMSCl) at optional temperature in one-pot in good yield.

关键词： N-Boc-2 5-bis(trimethylsilyl)pyrrolidine trimethylsilylation one-pot

Synthesis of the C5-C10 Segment of Taurospongin A

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Chinese Chemical Letters 2000年第8期11卷 663-664页

作者： Zheng, GR Lu, W Cai, jc Chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

Stereoselective synthesis of C5-C10 segment 3 of taurospongin A (1) has been developed successfully from L-(-)-malic acid.

关键词： stereoselective synthesis taurospongin A L-(-)-malic acid