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101.
为了解决传统加固服务器主模块可靠性差和稳定性差的问题,提出了一种基于ATCA架构的加固主模块设计方法;该方法包括了基于冗余-48V的高性能服务器处理器供电电路设计技术、基于ECC校验的DDR2高带宽数据存储电路设计技术、基于SATA的高速存储技术等关键技术;经过了大量的测试和试验验证,该种新型的加固服务器主模块能够在恶劣环境下稳定运行,可靠性和稳定性都有了很大的提升。 相似文献
102.
§ 1.Introduction LetRbearingwithidentityandMaleftR module .AleftR moduleUiscalledM injectiveif,foreverysubmoduleNofMandeveryhomomorphism :N→U ,canbeextendedtoahomomorphism ψ :M→U .AleftR moduleMiscalledaV modulebyRamamurthi[1]andTominaga[2 ](andiscalledaco semis… 相似文献
103.
研发并报道一个全新的130万像素电子内窥镜微型摄像模组.该模组采用低压差分信号技术实现图像数据的长距离高保真传输,它包括一个1/5.5英寸、分辨率为1 280×1 024像素的CMOS图像传感器,一个视场角为140°的小型镜头以及2个电路板.小型镜头座直接粘合到图像传感器的非光学窗口部分,两块印刷电路板垂直装配,使模组的尺寸缩小到长宽高分别为15.0 mm、5.5 mm、5.2 mm的空间.编码芯片将并行数字信号编码成低压差分信号经双绞线传出模组.搭建了实验系统并对摄像模组的实践性能进行评价.实验表明:模组分辨率达到136 lp·mm-1,图像传输距离达到2 m以上.紧凑的结构、高清分辨率图像、大视场和长传输距离使其适用于内窥镜诊治,特别是高清胃镜和结肠镜. 相似文献
104.
刻划半群上的同余及其扩张是半群的代数理论中的一个非常重要的课题.本文讨论了带上的同余的正规性和不变性以及在其Hall半群上的扩张,从同余扩张的角度刻划了带上的同余的性质,给出了扩张的极大、极小同余的描述. 相似文献
105.
B.P. Duggal 《Journal of Mathematical Analysis and Applications》2005,312(2):502-513
A Hilbert space operator T∈B(H) is hereditarily normaloid (notation: T∈HN) if every part of T is normaloid. An operator T∈HN is totally hereditarily normaloid (notation: T∈THN) if every invertible part of T is normaloid. We prove that THN-operators with Bishop's property (β), also THN-contractions with a compact defect operator such that and non-zero isolated eigenvalues of T are normal, are not supercyclic. Take A and B in THN and let dAB denote either of the elementary operators in B(B(H)): ΔAB and δAB, where ΔAB(X)=AXB−X and δAB(X)=AX−XB. We prove that if non-zero isolated eigenvalues of A and B are normal and , then dAB is an isoloid operator such that the quasi-nilpotent part H0(dAB−λ) of dAB−λ equals −1(dAB−λ)(0) for every complex number λ which is isolated in σ(dAB). If, additionally, dAB has the single-valued extension property at all points not in the Weyl spectrum of dAB, then dAB, and the conjugate operator , satisfy Weyl's theorem. 相似文献
106.
邱卫根 《数学的实践与认识》2006,36(1):227-231
提出了物元等价类概念,并利用子集合X和属性子集R对物元集合S(U,A,V,f)在集合论域U上构造了一类可拓集合A~,并讨论了A~关于X和R的一些相关性质. 相似文献
107.
Engin Büyükaşık Edgar Enochs J. R. García Rozas Gizem Kafkas-Demirci Sergio López-Permouth Luis Oyonarte 《代数通讯》2018,46(2):764-779
Relative notions of flatness are introduced as a mean to gauge the extent of the flatness of any given module. Every module is thus endowed with a flatness domain and, for every ring, the collection of flatness domains of all of its modules is a lattice with respect to class inclusion. This lattice, the flatness profile of the ring, allows us, in particular, to focus on modules which have a smallest flatness domain (namely, one consisting of all regular modules.) We establish that such modules exist over arbitrary rings and we call them Rugged Modules. Rings all of whose (cyclic) modules are rugged are shown to be precisely the von Neumann regular rings. We consider rings without a flatness middle class (i.e., rings for which modules must be either flat or rugged.) We obtain that, over a right Noetherian ring every left module is rugged or flat if and only if every right module is poor or injective if and only if R = S×T, where S is semisimple Artinian and T is either Morita equivalent to a right PCI-domain, or T is right Artinian whose Jacobson radical properly contains no nonzero ideals. Character modules serve to bridge results about flatness and injectivity profiles; in particular, connections between rugged and poor modules are explored. If R is a ring whose regular left modules are semisimple, then a right module M is rugged if and only if its character left module M+ is poor. Rugged Abelian groups are fully characterized and shown to coincide precisely with injectively poor and projectively poor Abelian groups. Also, in order to get a feel for the class of rugged modules over an arbitrary ring, we consider the homological ubiquity of rugged modules in the category of all modules in terms of the feasibility of rugged precovers and covers for arbitrary modules. 相似文献
108.
S. ter Horst M. Messerschmidt A.C.M. Ran M. Roelands M. Wortel 《Indagationes Mathematicae》2018,29(5):1350-1361
In recent years the coincidence of the operator relations equivalence after extension (EAE) and Schur coupling (SC) was settled for the Hilbert space case. For Banach space operators, it is known that SC implies EAE, but the converse implication is only known for special classes of operators, such as Fredholm operators with index zero and operators that can in norm be approximated by invertible operators. In this paper we prove that the implication EAE SC also holds for inessential Banach space operators. The inessential operators were introduced as a generalization of the compact operators, and include, besides the compact operators, also the strictly singular and strictly co-singular operators; in fact they form the largest ideal such that the invertible elements in the associated quotient algebra coincide with (the equivalence classes of) the Fredholm operators. 相似文献
109.
Kevin E.M. Church Robert Smith? 《Journal of Mathematical Analysis and Applications》2018,457(1):616-644
The time-scale tolerance for linear ordinary impulsive differential equations is introduced. How large the time-scale tolerance is directly reflects the degree to which the qualitative dynamics of the linear impulsive system can be affected by replacing the impulse effect with a continuous (as opposed to discontinuous, impulsive) perturbation, producing what is known as an impulse extension equation. Theoretical properties related to the existence of the time-scale tolerance are given for periodic systems, as are algorithms to compute them. Some methods are presented for general, aperiodic systems. Additionally, sufficient conditions for the convergence of solutions of impulse extension equations to the solutions of their associated impulsive differential equation are proven. Counterexamples are provided. 相似文献
110.
Given a family of Calabi-Yau varieties over the punctured disc or over the field of Laurent series, we show that, after a finite base change, the family can be extended across the origin while keeping the canonical class trivial. More generally, we prove similar extension results for families whose log-canonical class is semi-ample. We use these to show that the Berkovich and essential skeleta agree for smooth varieties over C((t)) with semi-ample canonical class. 相似文献