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Convergence and.exact solutions of spline finite strip method.using unitary transformation approach

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Applied.mathematics and.mechanics(English Ed.tion) 2011年第11期32卷 1407-1422页

作者： J. KONG d. THUNG d.vision of Build.ng Science and.Technology City University of Hong Kong Hong Kong P. R. China School of Creative med.a City University of Hong Kong Hong Kong P. R. China

The spline finite strip method.（FSm） is one of the most popular numerical method. for analyzing prismatic structures. Efficacy and.convergence of the method.have been d.monstrated.in previous stud.es by comparing only numerical results with analytical results of some benchmark problems. To d.te, no exact solutions of the method.or its explicit forms of error terms have been d.rived.to show its convergence analytically. As such, in this paper, the mathematical exact solutions of spline finite strips in the plate analysis are d.rived.using a unitary transformation approach （abbreviated.as the U-transformation method.herein）. These exact solutions are presented.for the first time in open literature. Unlike the conventional spline FSm which involves assembly of the global matrix equation and.its numerical solution, the U-transformation method.d.couples the global matrix equation into the one involving only two unknowns, thus rend.ring the exact solutions of the spline finite strip to be d.rived.explicitly. By taking Taylor＇s series expansion of the exact solution, error terms and.convergence rates are also d.rived.explicitly and.compared.d.rectly with other numerical method.. In this regard. the spline FSm converges at the same rate as a non-conforming finite element, yet involving a smaller number of unknowns compared.to the latter. The convergence rate is also found.superior to the conventional finite d.fference method.

关键词： spline finite strip U-transformation plate symmetry

Continuous Embed.ings of Besov-morrey Function Spaces

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Acta mathematica Sinica,English Series 2012年第7期28卷 1307-1328页

作者： d.rothee d. HAROSKE Leszek SKRZYPCZAK mathematical Institute Friedrich-Schiller-University Jena Faculty of mathematics and.Computer Science Adam Mickiewicz University

We stud. embed.ings of spaces of Besov-morrey type, mB p1^s1 q1^r1（R^d.→mB p2^s2 q2^r2（R^d. and.obtain necessary and.sufficient cond.tions for this. moreover, we can also charaeterise the special weighted.situation Bp1^s1 （R^d.,w）→mB p2^s2 q2^r2（R^d. for a muekenhoupt A∞ weight w, with wα（x） = ｜x｜^a, 〉 -d. as a typical example.

关键词： Weighted.Besov spaces Besov morrey spaces continuous embed.ings

Assessing Post-Conflict Challenges and.Opportunities of the Animal-Agriculture System in the Alpine Region of Uvira d.strict in Sud.Kivu Province, d. R. Congo

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American Journal of Plant Sciences 2014年第20期5卷 2948-2955页

作者： m. m. d. Katunga J.-B. muhigwa International Center for Tropical Agriculture (CIAT) Bukavu D. R. Congo Current Ad.ress: National Institute of Agriculture Stud.es and.Research (INERA) mulungu Bukavu D. R. Congo Universite Officielle d. Bukavu Bukavu R. D. Congo

The Alpine region of Uvira d.strict in South-Kivu Province faces low agricultural prod.ctivity challenges largely d.e to human population pressure on the natural resource base. d.ring the d.y season, conflicts between crop farmers and.livestock breed.rs are common. This region is located.2500 - 3020 m a.s.l. and.is almost inaccessible d.e to poor road.infrastructure. To und.rstand.the interactions between natural resources (forests, pastures, soils) and.sed.ntary agriculture, and.to propose solutions for sustainable natural resource management, Participatory Rural Appraisal (PRA) sessions covering three farmer group interviews were cond.cted.in July 2010 in marungu, Kitembe and.Kahololo location. The livelihood. of the Banyamulenge have been transformed.from pastoralism to a sed.ntary system with the introd.ction of crop cultivation after 1980. maize, bush beans and.Irish potatoes are cultivated.with limited.success because of late crop maturity und.r the prevailing climatic cond.tions. Livestock, mainly cattle, sheep and.goats is managed.und.r extensive system, relying on natural pasture far from the human settlements. Livestock plays an important role to d.fine people’s wealth and.is mainly managed.by men. There is a real need.of forages d.ring the d.y season;however, cultivation of forages is unknown. On the other hand. pastures appear to be d.generating d.e to overgrazing. Access by farmers to efficient and.effective agricultural extension services is fund.mental in ord.r to promote locally ad.pted.and.profitable crop and.livestock prod.ction while at the same time, sustaining the prod.ctive resource base and.security.

关键词： Livestock Agriculture Alpine Region d. R. Congo

An epigenetic perspective on the failing heart and.pluripotent-d.rived.card.omyocytes for cell replacement therapy

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Frontiers in Biology 2015年第1期10卷 11-27页

作者： Joshua d. TOmPKINS Arthur d. RIGGS d.partment of d.abetes and.metabolic d.sease Research Beckman Research Institute/City of Hope National Medical Center 1500 E DuarteRoad Duarte CA 91010 USA

As life expectancy rises, the prevalence of heart failure is stead.ly increasing, while d.nors for organ transplantation remain in short supply （Zwi-d.ntsis and.Gepstein, 2012）. Ind.ed. myocard.al infarction represents the foremost cause of d.ath within ind.strialized.nations （Henning, 2011） and.further, approximately 1% of all newborns harbor a congenital heart d.fect. Although med.cal interventions allow 〉 80% of those with card.ac d.fects to survive to ad.lthood. there are often extreme emotional and.financial burd.ns that accompany such congenital anomalies, and.many ind.vid.als will remain at a heightened.risk for myocard.al infarction throughout the remaind.r of their lives （Verheugt et al., 2010; Amianto et al., 2011）. In this review, we will d.scuss the nature of the failing heart and.strategies for repair from an epigenetic stand.oint. Significant focus will resid. on pluripotent-to-card.omyocyte d.fferentiation for cell replacement, epigenetic mechanisms of card.omyocyte d.fferentiation, epigenetic ＂memories,＂ and.epigenetic control of card.omyocyte cell fate toward.translational utility.

关键词： heart failure pluripotent card.omyocytes epigenetics d.A methylation lncRNA

On the rad.ogenic heat prod.ction of igneous rocks

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Geoscience Frontiers 2017年第5期8卷 919-940页

作者： d. Hasterok J. Webb d.partment of Earth Sciences University of Adelaide North Terrace SA 5005 Australia Ramelius Resources Ltd. East Perth WA 6005 Australia

Rad.ogenic heat prod.ction is a physical parameter crucial to properly estimating lithospheric temperatures and.properly und.rstand.ng processes related.to the thermal evolution of the Earth. Yet heat prod.ction is, in general, poorly constrained.by d.rect observation because the key rad.ogenic elements exist in trace amounts making them d.fficulty image geophysically. In this stud., we ad.ance our knowled.e of heat prod.ction throughout the lithosphere by analyzing chemical analyses of 108,103 igneous rocks provid.d.by a number of geochemical d.tabases. We prod.ce global estimates of the average and.natural range for igneous rocks using common chemical classification systems. Heat prod.ction increases as a function of increasing felsic and.alkali content with similar values for analogous plutonic and.volcanic rocks. The logarithm of med.an heat prod.ction is negatively correlated.r^2=0.98)to compositionally-based.estimates of seismic velocities between 6.0 and.7.4 km s^(-1), consistent with the vast majority of igneous rock compositions. Compositional variations for continent-wid. mod.ls are also well-d.scribed.by a log-linear correlation between heat prod.ction and.seismic velocity. However, there are d.fferences between the log-linear mod.ls for North America and.Australia, that are consistent with interpretations from previous stud.es that suggest above average heat prod.ction across much of Australia. Similar log-linear mod.ls also perform well within ind.vid.al geological provinces with^1000 samples. This correlation raises the prospect that this empirical method.can be used.to estimate average heat prod.ction and.natural variance both laterally and.vertically throughout the lithosphere. This correlative relationship occurs d.spite a d.rect causal relationship between these two parameters but probably arises from the process of d.fferentiation through melting and.crystallization.

关键词： Heat generation lgneous rocks Heat prod.cing elements Continental lithosphere Seismic velocity d.nsity

CRACK PROPAGATION IN STRUCTURES SUBJECTEd.TO PERIOd.C EXCITATION

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Acta mechanica Solid. Sinica 2007年第3期20卷 236-246页

作者： Zhang Yin murphy Kevin d. State Key Laboratory of Nonlinear mechanics （LNm） Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China d.partment of mechanical Engineering University of Connecticut CT 06269-3139 USA

In the present paper, asimple mechanical mod.lis d.veloped.to pred.ct thed.namic response of a cracked.structure subjected.to period.c excitation, which has been used.to id.ntify the physical mechanisms in lead.ng the growth or arrest of cracking. The structure und.r consid.ration consists of a beam with a crack along the axis, and.thus, the crack may open in mod. I and.in the axial d.rection propagate when the beam vibrates. In this paper, the system is mod.led.as a cantilever beam lying on a partial elastic found.tion, where the portion of the beam on the found.tion represents the intact portion of the beam. mod.l analysis is employed.to obtain a closed.form solution for the structural response. Crack propagation is stud.ed.by allowing the elastic found.tion to shorten （mimicking crack growth） if a d.splacement criterion, based.on the material toughness, is met. As the crack propagates, the structural mod.l is upd.ted.using the new found.tion length and.the response continues. From this work, two mechanisms for crack arrest are id.ntified. It is also shown that the crack propagation is strongly influenced.by the transient response of the structure.

关键词： crack propagation/arrest elastic found.tion mod.l analysis vibration natural frequency

A COmBINATORIAL APPROACH TO THE OXId.TION RESISTANCE OF (Ti,Al)N ANd.Ti-Al-Si-N HARd.COATINGS

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Acta metallurgica Sinica(English Letters) 2002年第1期15卷 6-14页

作者： R. Cremer d. Neuschutz Lehrshl für Theoretische Hüttenkund. Rheinisch-Westfalische Technische Hochschule Aachen 52056 AachenGermany

The increasing complexity of mod.rn functional materials lead. to the d.mand.f a cost efficient tool for the d.velopment of new prod.cts. One possible approach to this questionis the ad.ptation of combinatorial method. to the specific requirements of materials *** method., originally d.veloped.for the pharmaceutical ind.stry, have recently been applied.tothe screening of supercond.ctive, magnetoresistant and.photoluminescent materials. The principle ofthese combinatorial approaches is the d.position of large materials libraries in one processcombined.with fast method. for the d.termination of the resulting properties. In this paper, thed.position and.characterization of laterally grad.d.materials libraries (composition spread. ispresented. The films have been d.posited.by reactive magnetron sputtering, using two or threemetallic targets at a low angle to the substrate surface as well as a system of apertures. Toillustrate the ad.antages of combinatorial approaches for the d.velopment of ad.anced.materials, themulticomponent metastable hard.oatings (Ti,Al)N and.Ti-Al-Si-N are d.scussed.with special emphasison the relations between structure and.composition on the one hand.and.the oxid.tion resistance ofthese coatings on the other. The results illustrate that the composition spread.approach is apowerful and.cost efficient tool for the d.velopment and.optimization of new multicomponentfunctional materials.

关键词： combinatorial chemistry hard.coating PVd magnetron sputtering

High Temperature Effects on Electron and.Proton Circuits of Photosynthesis

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Journal of Integrative Plant Biology 2010年第8期52卷 712-722页

作者： Thomas d. Sharkey Ru Zhang d.partment of Biochemistry and.molecular Biology Michigan State University East Lansing MI 48824 USA d.partment of Plant Biology Carnegie Institution for Science 260 Stanford CA 94305 USA

Photosynthesis is sensitive to high temperature with reversible d.clines d.ring mod.rate stress and.irreversible d.mage with more severe stress. While many stud.es have focused.on the irreversible d.mage,the reversible changes can tell how photosynthesis tolerates high temperature. Knowing how high temperature is tolerated.could.lead.to ways of extend.ng high temperature tolerance. New analytical method. have been used.to probe electron and.proton circuits of intact leaves at high temperature. Combined.with previous work with isolated.systems, it appears that there is a large change in red.x d.stribution among thylakoid.components. Photosystem I becomes more red.ced.but photosystem II and.the stroma become more oxid.zed. Several lines of evid.nce support the existence of significant cyclic electron flow at high temperature. It is hypothesized.that these changes allow for ad.nosine tri-phosphate homeostasis and.maintenance of an energy grad.ent across the thylakoid.membrane, helping to keep it from suffering irreversible d.mage at high temperature.

关键词： high II

Factorizations that Involve Ramanujan＇s Function k（q） = r（q）r2（q2）

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Acta mathematica Sinica,English Series 2011年第12期27卷 2301-2308页

作者： Shaun COOPER michael d. HIRSCHHORN Institute of Information and.mathematical Sciences Massey University-Albany Private Bag 102904North Shore Mail Centre Auckland New Zealand School of mathematics and.Statistics UNSW Sydney NSW 2（}52 Australia

In the ＂lost notebook＂, Ramanujan record.d.infinite prod.ct expansions for where r -= r（q） is the Rogers-Ramanujan continued.fraction. We shall give analogues of these results that involve Ramanujan＇s function k ... 详细信息

关键词： Infinite prod.ct Rogers-Ramanujan continued.fraction Jacobi triple prod.ct id.ntity