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61.
White WJ  Lawrie RA 《Meat science》1985,12(2):117-123
The method for the detection and possible quantification of the unusual amino acid 3-methyl-l-histidine has been refined and elucidated. This is an essential prerequisite for the determination of its value as a robust unequivocal index of lean meat protein.  相似文献   
62.
The layer removal analysis of residual stress distribution is examined for mouldings which contain depth-varying Young's modulus. The approach is to compute the stress distribution which would be derived from the layer removal procedure if the assumption is made that the Young's modulus is uniform, and to compare it with the actual stress distribution. For this analysis a parabolic stress distribution is assumed to be present, and computed distributions are obtained for two cases, (i) in which the modulus varies linearly from the surface to the centre of the moulding and (ii) in which the modulus has a constant value near to the surface (skin) then changes suddenly to another constant value in the interior (core). The general features of the computed profiles are compared with experimental layer removal analyses conducted on injection-moulded specimens and the extent to which non-uniform modulus influences the results of such studies is discussed.  相似文献   
63.
Summary This paper deals with discounted Markov decision processes, Markov with respect to a finite statespaceI, where for eachiI, and each decision epocht, there is a finite action space K(i, t). The paper is concerned with problems which are formulated in terms of the discounted rewards in several ways. In order to ensure that optimal, or near optimal, policies are obtained, the state spaceI is extended to augmented state-spaces A(n), or A(), including the accumulated discounted rewards. Specimen problems are formulated and some computational aspects examined.
Zusammenfassung Es werden diskontierte Markovsche Entscheidungsprozesse behandelt mit endlichem Zustandsraum I, wobei die Mengen der zulässigen Entscheidungen K(i, t) vom Zustandi I und vom Zeitpunktt abhängen können. Es werden verschiedene Zielfunktionen betrachtet, die jeweils als Funktion des diskontierten Gesamtgewinns (nicht dessen Erwartungswerts) formuliert werden. Um optimale oder fast-optimale Politiken zu erhalten ohne die gesamte Vorgeschichte zu registrieren, wird der Zustandsraum um die akkumulierten diskontierten Auszahlungen erweitert. Eine Auswahl solcher Probleme wird exemplarisch diskutiert einschließlich einiger Aspekte der numerischen Behandlung.
  相似文献   
64.
Summary We integrate two numerical procedures for solving the average reward Markov decision process (MDP), standard successive approximations and modified policy iteration with reward revision. Reward revision is the process of revising the reward structure of a second, more computationally desirable MDP so as to produce, in the limit, an optimality equation having a fixed point identical to that associated with the original MDP. A numerical study indicates that for MDP's having a non-sparse transition structure with a small number of relatively large entries per row, the addition of reward revision can have significant computational benefits.
Zusammenfassung Zur Lösung Markovscher Entscheidungsprozesse (MDP) mit Durchschnitts-Kriterium werden zwei numerische Verfahren, nämlich sukzessive Approximation und modifizierte Politik-Iteration, mit einer Transformation, der sogenannten 'Reward-Revision, kombiniert. Bei dieser Transformation werden die Übergangswahrscheinlichkeiten so abgeändert (ausgedünnt), daß das neue Modell sich numerisch günstiger verhält. Dazu müssen die einstufigen Erträge so revidiert werden, daß die Optimalitäts-Gleichung des neuen Modells im Limes mit der des ursprünglichen übereinstimmt. Numerische Untersuchungen zeigen, daß für MDP mit stark besetzten Übergangsmatrizen, bei denen nur an wenigen Stellen je Zeile große Werte stehen, die Anwendung von 'Reward Revision zu wesentlichen Einsparungen an Rechenaufwand führen kann.


Research supported by NSF Grant ECS-8319355  相似文献   
65.
A variety of different imaging techniques produce data which naturally lie in stratified spaces. These spaces consist of smooth regions of maximal dimension glued together along lower dimensional boundaries. Diffusion processes are important as they can be used to represent noise in statistical models on spaces for which standard parametric probability distributions do not exist. We consider particles undergoing Brownian motion in some low dimensional stratified spaces, and obtain analytic solutions to the heat equation specifying the distribution of particles. These solutions play the role of prototypical distributions for studying behaviour near singularities. While probabilistic reasoning can be used to solve the heat equation in some straightforward cases, more generally we construct solutions from eigenfunctions of the Laplacian. Specifically, we solve the heat equation on: open books; two-dimensional cones; the Petersen graph with unit edge length; and the cone of this graph which corresponds to a space of evolutionary trees.  相似文献   
66.
Adsorption and desorption of hydrogen and coadsorption of H2 with H2O and CO over Ru(00l) surface have been studied under UHV conditions using the technique of TDS. Surface hydrogen interacts with adsorbed water resulting in an additional desorption state at 510 K which is not easily displaced by CO, but the total number of adsorption sites for hydrogen adsorption is independent of the amount of H2O predosed at room temperature. Hydrogen adsorption is blocked easily by CO dose (more than 0.5 L) or a small amount of O(a) formed from dissociative adsorption of water, and adsorbed hydrogen formed in the absence of significant water is easily displaced by CO dose at even room temperature.  相似文献   
67.
The high-resolution structure of several specific DNA-bindingproteins have been determined, and they display a common structuralmotif which mediates their binding to DNA. This motif consistsof two -helices connected by a sharp turn, and its amino acidsequence has several distinguishing features. A computer searchof the proteins coded by the genome of bacteriophage T7 hasbeen performed in an attempt to identify those proteins thatpotentially contain this motif. Eight proteins were found tohave regions similar to that of the motif. Of these, three arerelatively small, have no known function and are good candidatesfor being DNA-binding regulatory proteins. The methods describeduse commonly available computer programs and databases, andare therefore easy to implement.  相似文献   
68.
HD 《电脑迷》2014,(10):65-65
正英特尔南下攻略的成功,也推动了低价Widnows 8平板的崛起,习惯了安卓平板电脑的亲们,在使用Windows 8平板时总容易遇到这样那样的问题,尤其是联网激活的异常,让不少购买预置正版Windows 8平板的用户大感郁闷,笔者在此特以昂达Windows 8平板为例,对Windows 8平板使用过程中遇到的系统和软件激活问题进行讲解。  相似文献   
69.
HD 《电脑迷》2014,(9):18-18
正小编提示针对平板电脑外接手柄应用的软件较多,在按键映射及兼容性上各有所长,除《Sixaxis Controller》外,用户也可尝试《Tincore Keymapper》、《安卓手柄助手》等软件,寻找能同自己硬件平台对接最好的软件,以获得游戏体验。  相似文献   
70.
HD 《电脑迷》2014,(11):26-27
正体验过SSD固态硬盘的速度绝对不会想再忍受HDD机械硬盘的"龟速",面对大容量SSD固态硬盘不断刷新的最低价,有多少人能不动心?从台式机到笔记本,全方位的SSD升级势在必行。相对于看主控选SSD固态硬盘而言,如何分辨SSD固态硬盘的接口对于普通消费者而言恐怕更加实用。让我们从接口入手,一步一步了解SSD固态硬盘的奥秘吧!  相似文献   
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