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91.
In this paper, we study an inexact version of the alternating direction method of multipliers (ADMM) for solving two-block separable linearly constrained convex optimization problems. Specifically, the two subproblems in the classic ADMM are allowed to be solved inexactly by certain relative error criteria, in the sense that only two parameters are needed to control the inexactness. Related convergence analysis are established under the assumption that the solution set to the KKT system of the problem is not empty. Numerical results on solving a class of sparse signal recovery problems are also provided to demonstrate the efficiency of the proposed algorithm. 相似文献
92.
We report the kinetic analysis and mechanism for the initial steps of pyrolysis and combustion of a new fuel material, 1,6-dicyclopropane-2,4-hexyne, that has enormous heats of pyrolysis and combustion, making it a potential high-energy fuel or fuel additive. These studies employ the ReaxFF force field for reactive dynamics (RD) simulations of both pyrolysis and combustion processes for both unimolecular and multimolecular systems. We find that both pyrolysis and combustion initiate from unimolecular reactions, with entropy-driven reactions being most important in both processes. Pyrolysis initiates with extrusion of an ethylene molecule from the fuel molecule and is followed quickly by isomerization of the fuel molecule, which induces additional radicals that accelerate the pyrolysis process. In the combustion process, we find three distinct mechanisms for the O(2) attack on the fuel molecule: (1) attack on the cyclopropane, ring expanding to form the cyclic peroxide which then decomposes; (2) attack onto the central single bond of the diyne which then fissions to form two C(5)H(5)O radicals; (3) attack on the alkyne-cyclopropane moiety to form a seven-membered ring peroxide which then decomposes. Each of these unimolecular combustion processes releases energy that induces additional radicals to accelerate the combustion process. Here oxygen has major effects both as the radical acceptor and as the radical producer. We extract both the effective activation energy and the effective pre-exponential factor by kinetic analysis of pyrolysis and combustion from these ReaxFF simulations. The low value of the derived effective activation energy (26.18 kcal/mol for pyrolysis and 16.40 kcal/mol for combustion) reveals the high activity of this fuel molecule. 相似文献
93.
自然灾害恢复重建的关键之一,是救济基金的筹集.论文基于联盟博弈的理论分析了国家财政拨款、地方财政拨款、红十字会等社会机构募捐三条途径,对国家财政、地方财政、社会募捐机构三方, 应筹集救济基金的比例进行了论证.使全社会对恢复重建救济基金筹集的满意度最大. 相似文献
94.
现时,不少塑料大棚的拱架采用冷弯成形的力法,但是这一加工工艺却导致拱架强度发生严重的畸形;在拱架承受负弯矩的截面上,强度过分安全;而在其承受正弯矩的截面上,强度则严重不足。为纠正上述弊病,本文提出一个可行的方法——应变时效处理,此法的优点是花费不多且简单易行。 相似文献
95.
讨论了对二维核磁共振数据进行噪声剔除与数据压缩的一般原理与方法,介绍在Sun图形工作站上的实现情况,并给出实验结果与分析。 相似文献
96.
关于G-M成果研究的若干新动态Ⅰ——G-M型空间的若干品种 总被引:1,自引:1,他引:0
结合自己的工作,对Gowers-Maurey系列成果获Fields奖以来的研究的新动态作一综述。本是上篇,主要讨论含遗传不可分解空间在内的G-M型空间的若干品种。 相似文献
97.
拓展了适用于多种作图群体的检测数量性状基因座位(QTL)与分子标记(ML)间连锁关系的方差分析模型,并提出利用该方差分析之期望均方,在一定的遗传假定前提下,能够用于估计ML与QTL间的重组值.文章最后给出了一个分析实例,将水稻广亲和基因进行了定位. 相似文献
98.
胡家信 《数学物理学报(B辑英文版)》1997,(4)
1IntroductionWeareconcernedwiththefollowing2x2nonstrictly11yperbolicsystemofconservationlawswithinitialdatawhere(m,yi),i=1,2,3,areconstantstates.Wecall(1.1),(1.2)aRiemanll-typeproblelll,.Byaweaksolutionto(1.1),(1.2)wemeanapairofgeneralizedfullctions('IL.l,)(x,y.t)satisfyinglffeceivedFeb.17,1995;revisedApr.23,1996.SuPPortedbyNSFC(YOuth).foreacllof(T,y,f)6C:(R'xR )alld(u,U)(:r,;(/,f)~(it..())(x,y.0)ast-- 0 forallllostevery(x,if/,t)ERZxR .111(1.3).wealwaysassulllethat('(ti))(T,y.f)isals… 相似文献
99.
Sharp estimates of the point-evaluation functional in weighted Bergman spaces L
p
a
(Ω, dν
α) and for the point-evaluation derivalive functional in Besov spaces B
p
(Ω) are obtained for bounded symmetric domains Ω in ℂ
n
.
Received October 25, 1999, Accepted December 6, 2000 相似文献
100.
Chen Xinfang Yang Huai Cui Zhanchen Luo Yunxia Li Shuhua Xu Jun 《Radiation Physics and Chemistry》1993,42(1-3)
There is considerable interest in the effect of high energy radiation on triblock copolymer, SBS. Basheer and Dole have done some works about that(Basheer and Dole, 1982). In this paper, we study the effects of radiation crosslinking on the structure and mechanical properties of SBS, about which there have been no reports up to now. The following scientific problems are discussed:
The variation of glass transition temperatures with dose;
The effects of the ratio of B/S on the gel content;
Mechanical properties of the irradiated samples. 相似文献