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1.
《Quaestiones Mathematicae》2013,36(3):199-229
This paper is a direct continuation of the first paper in this series[Quaestiones Math. 8 (1985), no. 2,], which deals Kith the evolution problem [B(t)u(t)]' = A(t)u(t), Bu(0) = y. whereas in the first paper existence and uniqueness results were presented, this paper contains the ancillary results formulated in the first paper. These results describe the properties of B(t)-evolutions with non-stationary generating pairs, as well as of the solution operator of [B(t)u(t)]' = Au, Bu(0) = y.

The notation of the first paper is assumed throughout and is used without further note. Citation of results from the first paper is made by equation number. The numbering of this paper follows that of the first paper in sequence.  相似文献   

2.
本文是文献[4]的续。对于固定的FrameL,本文证明了每个LF-拟序集可以等价地表示为拟序的层,该结果与L-Fuzzy集的分解和表示定理类似。由这此定理可得出以下结论:一类量化Domain(例如,广义超度量Domain)实际上是将满足一定条件的拟序族进行"粘贴"的结果(按照层论的语言叙述,就是拟序的层),而通常的拟序则是常值拟序层的特例。  相似文献   

3.
A conventional problem of paper handling in a page-printing printer is to design a reliable paper path. Sometimes, this also affects the printing quality. The nonlinear theory of elastica has often been used to model paper deflection shape and to predict the paper path between some guiding rollers. The present paper proposes another method that can solve this problem more efficiently. Considering a piece of paper as a nonlinear beam, finite element analysis with geometric nonlinearity and manipulating the contact gap element between paper and guiding surfaces can be used to simulate the large-deflection behavior of paper. In this paper, the paper path in the vicinity of an OPC (organic photoconductive) drum is investigated with a general purpose finite element package. The effect of the electrostatic force between the OPC drum and the paper is considered, and the deformed shape of the paper for different forces lengths is obtained. According to those results an appropriate paper guide is added for an exact paper path.  相似文献   

4.
本文给出一个反例,证明了在一个Ponomarev-系统(f,M,X,P)中,P是点有限不蕴涵f是紧有限.这纠正了有关Ponomarev-系统的一个错误命题.作为Ponomarev-系统(f,M,X,P)的进一步结果,本文分别给出了f是紧映射以及P是点有限的充分必要条件.此外,本文还给出了Ponomarev-系统中映射与网络的一些其他关系.  相似文献   

5.
It is proved in this paper that(1) the topological sum of a family of supercomplete spaces is supercomplete;(2) if X is a metacompact and almost locally compact space then X is supercomplete. Moreover, some questions on supercomplete spaces are posed in the paper.  相似文献   

6.
In a recently published paper “A note on “A novel approach to multi attribute group decision making based on trapezoidal interval type-2 fuzzy soft sets””, Khalil and Hassan pointed out that assertions (3) and (4) of Theorem 3.2 in our previous paper “A novel approach to multi attribute group decision making based on trapezoidal interval type-2 fuzzy soft sets” are not true [2]. Furthermore, they introduced the notions of a generalized trapezoidal interval type-2 fuzzy soft subset and a generalized trapezoidal interval type-2 fuzzy soft equal and used these two notions to correct the flaw in assertions (3) and (4) of Theorem 3.2 in our previous paper. In this paper, we show by a counterexample that Khalil and Hassan's correction is incorrect and provide the modified versions of assertions (3) and (4) of Theorem 3.2, along with a strict proof. In addition, Khalil and Hassan pointed out by a counterexample that assertions (3)–(6) of Theorem 3.5 in our paper are not true and proposed the corrections of those assertions. In this paper, we show that Khalil and Hassan's counterexample and corrections are incorrect and provide a new example to verify the inaccuracies of assertions (3) and (5) of Theorem 3.5 in our paper. Moreover, we offer the modified versions of assertions (3) and (5) of Theorem 3.5 and prove them. Finally, Khalil and Hassan's statement that assertions (4) and (6) of Theorem 3.5 in our previous paper are not true is proven to be incorrect, i.e. assertions (4) and (6) of Theorem 3.5 in our previous paper are true.  相似文献   

7.
This paper is a continuation of the previous paper (J. Differential Equations 165 (2000) 255). The main subject is the Gevrey property of formal solutions of an analytic ordinary differential equation in powers of a parameter. In one case, a given formal solution itself is of the Gevrey type, while, in another case, the existence of a formal solution implies the existence of formal solutions of the Gevrey types. These situations are explained systematically in this paper.  相似文献   

8.
《数学季刊》2016,(4):430-434
It is proved in this paper that (1) the topological sum of a family of supercomplete spaces is supercomplete; (2) if X is a metacompact and almost locally compact space then X is supercomplete. Moreover, some questions on supercomplete spaces are posed in the paper.  相似文献   

9.
In a recent paper (Ref. 1), Cheng and Teo discussed some further extensions of a student-related optimal control problem which was originally proposed by Raggettet al. (Ref. 2) and later on modified by Parlar (Ref. 3). In this paper, we treat further extensions of the problem.This paper is a modified and improved version of Ref. 4. It is based, in part, on research sponsored by NSF.  相似文献   

10.
本文研究了连续函数代数C(X)与某个C*-代数 A的张量积C(X) A的自同构群.当 A是有单位元且具有平凡中心的C*-代数时,本文完全刻划了C(X) A的自同构群.利用AF-代数的K-理论,本文还刻划了当X是全不连通的紧致Hausdorff空间时,C(X)与紧算子理想的张量积的自同构群.  相似文献   

11.
《Applied Mathematical Modelling》2014,38(7-8):2214-2223
The quantification problem of recovering the original material distribution from secondary ion mass spectrometry (SIMS) data is considered in this paper. It is an inverse problem, is ill-posed and hence it requires a special technique for its solution. The quantification problem is essentially an inverse diffusion or (classically) a backward heat conduction problem. In this paper an operator-splitting method (that is proposed in a previous paper by the first author for the solution of inverse diffusion problems) is developed for the solution of the problem of recovering the original structure from the SIMS data. A detailed development of the quantification method is given and it is applied to typical data to demonstrate its effectiveness.  相似文献   

12.
This paper is devoted to dealing with a flaw that existed in a recent paper (Zhou et al. 2014). We give a new proof of Th. 3.1 in Zhou et al. (2014), which is a correction of the original proof.  相似文献   

13.
The major object of this paper is to provide a quite convenient regularization method for a nonlinear backward heat problem. Error estimates for this method are provided together with a selection rule for the regularization parameter. Our method improve some results in a previous paper, including the earlier paper [D.D. Trong, N.H. Tuan, Regularization and error estimate for the nonlinear backward heat problem using a method of integral equation, Nonlinear Anal. 71 (9) (2009) 4167–4176] and some other papers. A general case of nonlinear terms for this problem is obtained.  相似文献   

14.
严从荃  孙顺华 《数学学报》2000,43(4):763-768
本文研究了连续函数代数C(X)与某个C*-代数A的张量积C(X)A的自同构群.当A是有单位元且具有平凡中心的C*-代数时,本文完全刻划了C(X)A的自同构群.利用AF-代数的K-理论,本文还刻划了当X是全不连通的紧致Hausdorff空间时,C(X)与紧算子理想的张量积的自同构群.  相似文献   

15.
本文指出平移利率模型的风险市价是到期时间的线形函数并证明了平移利率模型是一种特殊的简单Gaussian利率模型.同时,文章还给出了简单Gaussian利率模型即期利率的条件概率分布.  相似文献   

16.
The paper deals with absolute summability factors for infinite series. The main purpose of this paper is to generalize a recent paper of Savas (2009) [2].  相似文献   

17.
Online test paper generation (Online-TPG) generates a test paper automatically online according to user specification based on multiple assessment criteria, and the generated test paper can then be attempted online by user. Online-TPG is challenging as it is a multi-objective optimization problem that is NP-hard, and it is also required to satisfy the online generation requirement. In this paper, we propose an efficient multi-objective optimization approach based on the divide-and-conquer memetic algorithm (DAC-MA) for Online-TPG. Instead of solving the multi-objective constraints simultaneously, the set of constraints is divided into two subsets of relevant constraints, which can then be solved separately and effectively by evolutionary computation and local search of DAC-MA. The empirical performance results have shown that the proposed approach has outperformed other TPG techniques in terms of runtime efficiency and paper quality.  相似文献   

18.
This survey paper starts with a critical analysis of various performance metrics for supply chain management (SCM), used by a specific manufacturing company. Then it summarizes how economic theory treats multiple performance metrics. Actually, the paper proposes to deal with multiple metrics in SCM via the balanced scorecard — which measures customers, internal processes, innovations, and finance. To forecast how the values of these metrics will change — once a supply chain is redesigned — simulation may be used. This paper distinguishes four simulation types for SCM: (i) spreadsheet simulation, (ii) system dynamics, (iii) discrete-event simulation, and (iv) business games. These simulation types may explain the bullwhip effect, predict fill rate values, and educate and train users. Validation of simulation models requires sensitivity analysis; a statistical methodology is proposed. The paper concludes with suggestions for a possible research agenda in SCM. A list with 50 references for further study is included.  相似文献   

19.
The paper offers a new approach that allows unifying various regularity concepts used in variational analysis: the most fundamental local regularity triad (openness at a linear rate – metric regularity – Aubin property), the calmness–subregularity pair, directional regularity, upper Lipschitz continuity etc. The main new element of the approach is the appearance of a new parameter which is a set to which regularity is related (whence the term “relative regularity” used in the paper to name the general property). The main emphasis is put on characterizations of relative regularity and its stability with respect to additive perturbations of the (generally set-valued) mapping. A discussion of a relative extension of strong regularity properties concludes the paper.  相似文献   

20.
设S是幺半群.本文介绍并研究了正则右系的一个推广.一个右S-系A称为C(P)系,如果A的所有循环子系满足条件(P).本文证明了右C(P)系形成了右S-系的一个新的类,同时,C(P)性质为幺半群同调分类研究提供了新思路.  相似文献   

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