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1.
Hans Weber 《Order》2007,24(4):249-276
We study lattice theoretical properties of lattices of uniformities such as modularity, distributive laws and the existence of (relative) complements. For this the concepts of permutable uniformities (see Definition 3.1) and independent uniformities (see Definition 4.1) are important. Moreover, we show that e.g. the lattice of all lattice uniformities on a lattice L is a closed sublattice of the lattice of all uniformities on L.  相似文献   
2.
The purpose of this paper is to decide the conditions under which a CM elliptic curve is modular over its field of definition.  相似文献   
3.
This paper presents a framework for finding optimal modules in a delayed product differentiation scenario. Historical product sales data is utilized to estimate demand probability and customer preferences. Then this information is used by a multiple-objective optimization model to form modules. An evolutionary computation approach is applied to solve the optimization model and find the Pareto-optimal solutions. An industrial case study illustrates the ideas presented in the paper. The mean number of assembly operations and expected pre-assembly costs are the two competing objectives that are optimized in the case study. The mean number of assembly operations can be significantly reduced while incurring relatively small increases in the expected pre-assembly cost.  相似文献   
4.
Reported herein is a fully orthogonal olefination, which involves the site- and E-selective coupling of aryl germanes with alkenes, tolerating otherwise widely employed coupling handles such as aromatic (pseudo)halogens (C−I, C−Br, C−Cl, C−F, C−OTf, C−OSO2F), silanes and boronic acid derivatives as well as alternative functionalities. This unprecedented [Ge]-based oxidative Heck coupling proceeds at room temperature with high speed (10 min to 2 hours) and operational simplicity owing to its base-free and air-tolerant features.  相似文献   
5.
设计和构建了多轴多模式、闭环伺服控制系统的研发平台,实现了用于气相色谱仪的不同结构的两种液体自动进样器的并行设计与研制。基于兼容与互换的思路,开发出一体化嵌入式控制驱动模块,采用相同的直流电机、编码器,电气与机械接口统一标准,实现了上述组件在两种机型间的直接代换。研制的标准型110个样品位和平台型40个样品位两种液体自动进样器,与气相色谱仪联机,采用1μL手动进样针,对于0.5μL十六烷-异辛烷标准液体样品,6个不同瓶位连续6次进样测试,重复进样的信号峰面积RSD分别为1.1%和1.5%,取0.1,0.3,0.5,0.7和0.9μL进样,峰面积与进样量的线性相关系数为0.9947。  相似文献   
6.
TL—子环上的TL—子模的格   总被引:2,自引:0,他引:2  
研究TL-子环上TL-子模形成的格及其子格的性质,给出这些格之间的同态与同构定理。  相似文献   
7.
Let E be a CM elliptic curve defined over an algebraic number field F. In the previous paper [N. Murabayashi, On the field of definition for modularity of CM elliptic curves, J. Number Theory 108 (2004) 268-286], we gave necessary and sufficient conditions for E to be modular over F, i.e. there exists a normalized newform f of weight two on Γ1(N) for some N such that HomF(E,Jf)≠{0}. We also determined the multiplicity of E as F-simple factor of Jf when HomF(E,Jf)≠{0}. In this process we separated into the three cases. In this paper we construct certain CM elliptic curves which satisfy the conditions of each case. In other words, we show that all three cases certainly occur.  相似文献   
8.
Spectral methods for graph clustering - A survey   总被引:3,自引:0,他引:3  
Graph clustering is an area in cluster analysis that looks for groups of related vertices in a graph. Due to its large applicability, several graph clustering algorithms have been proposed in the last years. A particular class of graph clustering algorithms is known as spectral clustering algorithms. These algorithms are mostly based on the eigen-decomposition of Laplacian matrices of either weighted or unweighted graphs. This survey presents different graph clustering formulations, most of which based on graph cut and partitioning problems, and describes the main spectral clustering algorithms found in literature that solve these problems.  相似文献   
9.
We show here that the problem of maximizing a family of quantitative functions, encompassing both the modularity (Q-measure) and modularity density (D-measure), for community detection can be uniformly understood as a combinatoric optimization involving the trace of a matrix called modularity Laplacian. Instead of using traditional spectral relaxation, we apply additional nonnegative constraint into this graph clustering problem and design efficient algorithms to optimize the new objective. With the explicit nonnegative constraint, our solutions are very close to the ideal community indicator matrix and can directly assign nodes into communities. The near-orthogonal columns of the solution can be reformulated as the posterior probability of corresponding node belonging to each community. Therefore, the proposed method can be exploited to identify the fuzzy or overlapping communities and thus facilitates the understanding of the intrinsic structure of networks. Experimental results show that our new algorithm consistently, sometimes significantly, outperforms the traditional spectral relaxation approaches.  相似文献   
10.
The paper discusses the currents status and future perspectives of the utilization of microwaves, as a selective and locally controlled heating method, in heterogeneous catalytic flow reactors. Various factors related to the microwave‐catalyst interaction and the design of microwave‐assisted catalytic reactor systems are analyzed. The analysis clearly shows the superiority of the traveling‐wave systems over the mono‐mode and multi‐mode cavity‐based systems when it comes to the design and application of microwave flow reactors at relevant production scales.  相似文献   
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