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1.
We introduce the notion of antisyzygies, which studies the inverse problem of finding a system of PDEs, given compatibility conditions. The system obtained possesses the property of removability of compact singularities. We write explicit computations in the cases of the Cauchy-Fueter system and Maxwell’s system for electromagnetism, and we conclude with a study of systems of non-maximal rank.   相似文献   
2.
In this paper we evaluate Chebyshev polynomials of the second kind on a class of symmetric integer matrices, namely on adjacency matrices of simply laced Dynkin and extended Dynkin diagrams. As an application of these results we explicitly calculate minimal projective resolutions of simple modules of symmetric algebras with radical cube zero that are of finite and tame representation type.  相似文献   
3.
振动声成像系统分辨率研究   总被引:1,自引:1,他引:0       下载免费PDF全文
本文从振动声成像的基本原理出发,通过引入点扩展函数PSF和定义轴向响应函数ARF,研究了由凹球面聚焦换能器分割而成的一种典型共焦换能器参数对振动声成像系统侧向分辨率和轴向分辨率的影响。计算研究表明:增大凹球面换能器的口径、减小几何焦距和提高中心频率均可以提高系统的侧向分辨率和轴向分辨率;但改变凹球面换能器的分割比例对两种分辨率影响不尽相同。综合考虑超声换能器激励、聚焦性能以及产生的辐射力效果等因素,则换能器应按等辐射面积原则分割为宜。文中还分析了介质的声衰减系数对实际轴向分辨率的影响。  相似文献   
4.
本文利用细菌视紫红质变种材料BRD96N的基态和M态实现了图象的高分辨存储.实验研究了该样品的吸收特性;在此基础上分析了散射光对BR膜图象质量的影响,并通过合理的控制激发光强和激发时间在BR膜样品上得到分辨率为800lp/mm的高分辨图象.  相似文献   
5.
Mari Sano 《代数通讯》2013,41(8):3053-3075
In Buchsbaum and Rota (1994 Buchsbaum , D. , Rota , G.-C. ( 1994 ). A new construction in homological algebra . Proc. Nat. Acad. Sci. 91 : 41154119 . [CSA] [CROSSREF] [Crossref], [PubMed], [Web of Science ®] [Google Scholar]), the authors presented a generalized bar complex associated to certain 3-rowed Weyl modules and proved that this complex is in fact a resolution via an induction on the number of overlaps between the second and third rows and a fundamental exact sequence (Akin and Buchsbaum, 1985 Akin , K. , Buchsbaum , D. ( 1985 ). Characteristic-free representation theory of the general linear group . Adv. Math 58 ( 2 ): 149200 . [CSA]  [Google Scholar]). In this article we study the structure of this resolution by constructing a splitting contracting homotopy for the complexes corresponding to certain shapes.  相似文献   
6.
7.
In Douglas et al. (2012) [9], the authors investigated a family of quotient Hilbert modules in the Cowen–Douglas class over the unit disk constructed from classical Hilbert modules such as the Hardy and Bergman modules. In this paper we extend the results to the multivariable case of higher multiplicity. Moreover, similarity as well as isomorphism results are obtained.  相似文献   
8.
Edward L. Green 《代数通讯》2013,41(11):4033-4054
This paper continues the study of n-full graphs and their connection to certain Koszul algebras started in Green and Hartman (to appear). We provide constructive methods for creating new full graphs from old and study the associated Koszul algebras and the projective resolution of simple modules over such algebras.  相似文献   
9.
A series of experiments and measurements demonstrate the importance of minimizing the extra-column band broadening contribution of the instrument used. The combination of several measures allowed the achievement of the full potential efficiency of three Kinetex-C18 columns, using a conventional liquid chromatograph. The first measure consists in minimizing the extra-column volume of the instrument, without increasing much its back pressure contribution, by changing the needle seat volume, the inner diameter and length of the capillary connectors, and the volume of the detector cell of a standard instrument (Agilent 1100). The second measure consists in injecting a volume of weak eluent (less than half the elution strength of the mobile phase) right after the sample, before the sample had time to reach the column. Experimental results show that these changes could provide most of the resolution expected from the true column performance. After the changes were made, the resolutions of the 2.1 mm ×× 50 mm, 4.6 mm ×× 50 mm, and 4.6 mm ×× 100 mm Kinetex-C18 columns for compounds having retention factors close to 1 were increased by about 180, 35, and 30%, respectively. The resolutions obtained are then similar to those measured with advanced instruments like the Agilent 1200, the Agilent 1290 Infinity HPLC, and the Acquity chromatographs.  相似文献   
10.
《代数通讯》2013,41(3):1427-1451
Abstract

In this paper we prove the existence of minimal level artinian graded algebras having socle degree r and type t and describe their h-vector in terms of the r-binomial expansion of t. We also investigate the graded Betti numbers of such algebras and completely describe their extremal resolutions. We also show that any set of points in ? n whose Hilbert function has first difference as described above, must satisfy the Cayley-Bacharach property.  相似文献   
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