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991.
Moschou EA Nicholson AD Jia G Zoval JV Madou MJ Bachas LG Daunert S 《Analytical and bioanalytical chemistry》2006,385(3):596-605
This work demonstrates the development of microfluidic compact discs (CDs) for protein purification and fractionation integrating a series of microfluidic features, such as microreservoirs, microchannels, and microfluidic fractionators. The CDs were fabricated with polydimethylsiloxane (PDMS), and each device contained multiple identical microfluidic patterns. Each pattern employed a microfluidic fractionation feature with operation that was based on the redirection of fluid into an isolation chamber as a result of an overflow. This feature offers the advantage of automated operation without the need for any external manipulation, which is independent of the size and the charge of the fractionated molecules. The performance of the microfluidic fractionator was evaluated by its integration into a protein purification microfluidic architecture. The microfluidic architecture employed a microchamber that accommodated a monolithic microcolumn, the fractionator, and an isolation chamber, which was also utilized for the optical detection of the purified protein. The monolithic microcolumn was polymerized “in situ” on the CD from a monolith precursor solution by microwave-initiated polymerization. This technique enabled the fast, efficient, and simultaneous polymerization of monoliths on disposable CD microfluidic platforms. The design of the CD employed allows the integration of various processes on a single microfluidic device, including protein purification, fractionation, isolation, and detection.
相似文献
992.
Francisco J. Fernández-Polo 《Journal of Functional Analysis》2010,259(2):343-358
We establish several generalisations of Urysohn's lemma in the setting of JB∗-triples which provide full answers to Problems 1.12 and 1.13 in Fernández-Polo and Peralta (2007) [22]. These results extend the previous generalisations obtained by C.A. Akemann, G.K. Pedersen and L.G. Brown in the setting of C∗-algebras. A generalised Kadison's transitivity theorem is established for finite sums of pairwise orthogonal compact tripotents in JBW∗-triples. We introduce the notion of positively open tripotent in the bidual of a JB∗-triple as an extension of a concept which was already considered in the setting of ternary rings of operators. We investigate the connections appearing between positively open tripotents and hereditary inner ideals. 相似文献
993.
Dikran Dikranjan Dmitri Shakhmatov 《Journal of Mathematical Analysis and Applications》2010,363(1):42-330
For an abelian topological group G, let denote the dual group of all continuous characters endowed with the compact open topology. Given a closed subset X of an infinite compact abelian group G such that w(X)<w(G), and an open neighborhood U of 0 in T, we show that . (Here, w(G) denotes the weight of G.) A subgroup D of G determines G if the map defined by r(χ)=χ?D for , is an isomorphism between and . We prove that
994.
We consider the single item lot-sizing problem with capacities that are non-decreasing over time. When the cost function is
(i) non-speculative or Wagner–Whitin (for instance, constant unit production costs and non-negative unit holding costs) and
(ii) the production set-up costs are non-increasing over time, it is known that the minimum cost lot-sizing problem is polynomially
solvable using dynamic programming. When the capacities are non-decreasing, we derive a compact mixed integer programming
reformulation whose linear programming relaxation solves the lot-sizing problem to optimality when the objective function
satisfies (i) and (ii). The formulation is based on mixing set relaxations and reduces to the (known) convex hull of solutions
when the capacities are constant over time. We illustrate the use and potential effectiveness of this improved LP formulation
on a few test instances, including instances with and without Wagner–Whitin costs, and with both non-decreasing and arbitrary
capacities over time.
This work was partly carried out within the framework of ADONET, a European network in Algorithmic Discrete Optimization,
contract no. MRTN-CT-2003-504438.
This text presents research results of the Belgian Program on Interuniversity Poles of Attraction initiated by the Belgian
State, Prime Minister’s Office, Science Policy Programming. The scientific responsibility is assumed by the authors. 相似文献
995.
In an earlier article we characterized, from the viewpoint of set theory, those closure operators for which the classical result of Birkhoff and Frink, stating the equivalence between algebraic closure spaces, subalgebra lattices and algebraic lattices, holds in a many‐sorted setting. In the present article we investigate, from the standpoint of category theory, the form these equivalences take when the adequate morphisms of the several different species of structures implicated in them are also taken into account. Specifically, our main aim is to provide a functorial rendering of the Birkhoff‐Frink representation theorems for both single‐sorted algebras and many‐sorted algebras, by defining the appropriate categories and functors, covariant and contravariant, involved in the process (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
996.
This paper aims at evaluating the link performance of an electronically steerable passive array radiator (ESPAR) in both rich
scattering and clustered channels. Previous work has shown that the performance of an ESPAR-antenna can be comparable to a
2 × 2 multiple-input-multiple-output (MIMO) system in a rich scattering environment. The design of the antenna patterns used
for transmission was based on intuition, and therefore cannot be guaranteed to be optimal. In this paper, we design the antenna
patterns by minimizing the average inner-product between signals that are transmitted with different antenna patterns. We
also evaluate the performance of the ESPAR-antenna at higher spectral-efficiencies than previous literature has done. The
performance in terms of spectral-efficiency is evaluated for both rich scattering environments and clustered channels, whereas
the performance in terms of symbol error rate is evaluated for rich scattering channels only.
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R. BainsEmail: |
997.
998.
由于湍流图像的退化原因十分复杂,现有图像复原算法很难在复原效率和复原质量间达到很好的平衡,为此提出了一种基于支持向量机的湍流退化图像加速复原算法.该算法通过设置方差阈值进行样本选择,舍弃了冗余信息、提高了样本质量;同时,对序列图像进行实时模型更新,加快了序列图像的复原速度.针对电弧风洞图像,将加速复原算法和原算法进行了比较.实验结果表明,加速算法的复原速度更快、复原效果也更好,它可以有效地解决湍流退化给图像带来的噪声和能量衰减问题,并能很好地校正湍流效应引起的模糊和抖动现象. 相似文献
999.
结合黑板系统及Agent技术,设计基于黑板的多Agent智能决策支持系统模型,同时对该模型中的各Agent功能进行描述。此外,提出系统中Agent的抽象结构,并对Agent的行为进行了描述和建模。该系统有助于多个Agent协同求解大规模复杂问题。 相似文献
1000.
随着企业规模的不断扩大,企业固定资产数目的种类也在与日俱增,传统的企业固定资产验证费时费力容易出错,而基于RFID(射频识别)的资产验证管理系统可大大提高验证的效率。介绍了RFID技术在固定资产验证管理系统中的应用,着重介绍了基于WinCE5.0平台的手持机端的开发以及PC端软件的开发。 相似文献