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1.
全新的键盘设计令7260显得十分吸引人。这款银白红相间版更是把那种古典的优雅与现代的潮流完美的结合在一起.从美学的角度上来看诺基亚的7260可以说得上是一款设计相当精美的艺术品,具有相当高的观赏价值。  相似文献   

2.
提出一种生成所有堆的枚举算法。该算法按照从深层次向低层次的顺序生成堆,采用单个数判断法。测试结果验证了该算法的有效性和可靠性。  相似文献   

3.
在软交换网络中,SIP和MGCP是两种非常重要的协议,然而,两者之间的互通也是个突出的问题.通过深入分析互通所涉及的协议转换、寻址、资源协商等关键问题的基础上,提出在媒体网关控制器实体中扩展互通功能模块的设计方案,该互通功能模块是用C语言编程实现,利用该互通功能模块建立起两个网络之间的点到点的呼叫.  相似文献   

4.
热闹喧嚣后的圣诞瘦街头,Reka Lorincz漫步在无人的巴塞罗那的一条小巷里,她独自伫立在橱窗前良久,端详着跳舞的圣诞老人,“为什么你只会在一年年末才来到我们的身边,然后销声匿迹一整年?那这一整年中,你都在哪里?”于是,在2004年,Reka把这些平日圣诞节过后被废弃的树、包装,甚至圣诞老人的头发,做成一系列作品。而她,也就这样走进了大众视野。  相似文献   

5.
随着数据业务的迅猛发展,NGN已经成为研究的热点.而SIP协议作为NGN中的关键协议,受到了广泛的关注,由于SIP是一种新型协议,所以在应用方面存在着很多问题.其中,在不损害网络安全性的情况下,如何使SIP信令顺利的通过NAT设备,成为热点问题.本文首先对SIP协议以及NAT技术进行了简要的介绍,然后对SIP穿越NAT设备的问题进行了详细的探讨,最后对RSIP协议进行了深入的分析.  相似文献   

6.
建立清晰合理的业务流程体系是ERP项目实施成功的关键因素,ERP作为一个管理工具主要提供决策支持数据及监控业务过程,而清晰合理的业务流程体系能保证ERP系统提供准确有效的数据而不是垃圾数据,同时保证业务系统更加规范,提高效率。  相似文献   

7.
姜波 《多媒体世界》2008,(20):78-78
这位海归CIO的经历,与业界很多失败项目的传说有诸多相似之处,某企业上了一套先进的大品牌的系统,项目往往在上线后没有了下文。如何避免出现上述案例的情形,应该注意以下几点。  相似文献   

8.
单片机在机器人中有着广泛的应用,但是由于计算性能欠佳,无法完成复杂的功能,需要使用上位机对其进行监控,本文针对ZKRT-300机器人采用C#环境设计了监控程序,就通讯协议及数据处理进行了论述.  相似文献   

9.
公司的主要业务是经营各种礼品,经营范围以满足市场需要为目的,公司的经营方式长期是以人工操作为主。为了提高工作效率,公司很早就购置了先进而昂贵的电脑设备,但是由于员工的使用水平有限,电脑的许多功能没有利用起来,以至花巨资买来的电脑仅仅作为台打字机使用,没有起到多大的作用,就要被淘汰掉。随着近年来公司业务的迅猛发展,传统的人工操作渐渐不能适应采购、销售、配送等多项业务同时开展的需要,制约了企业的发展。举例来说,公司有时会同时接到好几笔订单,有时又经常几周没有出货,所以业务员在进货时总是担心货多了少了,生怕货源不充足或者库存积压。随着观念的更新,客户对礼品的新颖程度和种类提出了越来越高的要求,公司在拓展货源方面面临着新的挑战。  相似文献   

10.
《数码摄影》2008,(11):24-31
2007年到2008年是第四次国际极地年,有关保护环境,保护地球的理论说教,我不想继续。我们奉献给读者的是这样一组美轮美奂的极地作品。对于这样极致的美丽,你还忍心去破坏它,去摧毁它吗?  相似文献   

11.
This paper presents a formal and executable approach to capture the behaviour of parties involved in a negotiation. A party is modeled as a negotiating agent composed of a communication module, a control module, a reasoning module, and a knowledge base. The control module is expressed as a statechart, and the reasoning module as a defeasible logic program. A strategy specification therefore consists of a statechart, a set of defeasible rules, and a set of initial facts. Such a specification can be dynamically plugged into an agent shell incorporating a statechart interpreter and a defeasible logic inference engine, in order to yield an agent capable of participating in a given type of negotiations. The choice of statecharts and defeasible logic with respect to other formalisms is justified against a set of desirable criteria, and their suitability is illustrated through concrete examples of bidding and multi-lateral bargaining scenarios.  相似文献   

12.
提出Vague值向Fuzzy值转化的实用方法的定义。针对文献[6]中的一个Vague值向Fuzzy值转化的均值修正法,提出了加权均值修正法,并证明了这种方法同样是Vague值向Fuzzy转化的一种非常实用的方法。  相似文献   

13.
Mechanics is described and equations are given of the motion of an actively bending homogeneous body of a finite thickness in a channel with dry friction under conditions of a weak bending. Control is suggested of the motion of a body in a sinusoidal channel, which retains a continuous first derivative of the controlling moment and a bounded second derivative. A process is described of the maximization of the speed of motion by control and then by the choice of the best parameters of a channel. Control is also considered of other modes of the motion of a body in the same channel.  相似文献   

14.
This paper describes a method for the state estimation of nonlinear systems described by a class of differential-algebraic equation models using the extended Kalman filter. The method involves the use of a time-varying linearisation of a semi-explicit index one differential-algebraic equation. The estimation technique consists of a simplified extended Kalman filter that is integrated with the differential-algebraic equation model. The paper describes a simulation study using a model of a batch chemical reactor. It also reports a study based on experimental data obtained from a mixing process, where the model of the system is solved using the sequential modular method and the estimation involves a bank of extended Kalman filters.  相似文献   

15.
The evaluation of points and the computations of inflection points or cusps on a curve are often necessary in CAGD applications. When a curve is represented in a B-spline form, such computations can be made easier once it is transformed into a set of piecewise polynomial curves in power form. The usual practice of the transformation of a B-spline curve into a set of piecewise polynomial curves in power form is done either by a knot refinement followed by basis conversions, or by applying a Taylor expansion on each knot span of a B-spline curve.Presented in this paper is a new algorithm to convert a B-spline curve into a set of piecewise polynomial curves in power form. Experiment shows that the proposed algorithm significantly outperforms the conventional approach when one or more control points of a B-spline curve are continuously moving.  相似文献   

16.
A tube is a solid bounded by the union of a one-parameter family of circles that may be decomposed into canal-surfaces and planar disks or annuli. A screw-sweep is the region swept by a shape during a screw motion. HelSweeper computes the boundary of a screw-sweep of an arbitrary union of tubes and polyhedra. To do so, it generates a superset of faces, splits them at their intersections, and selects the face portions that form the desired boundary. The novelty of the proposed approach lies in the fact that the faces contributed to this superset by a tube are each a screw-sweeps of a rigid curve (generator), which is the locus of grazing points, and that each grazing point is formulated as the intersection of a circle of the tube with a corresponding screw-plane. Hence, each such face is a one-parameter family of helices, each being the screw-sweep of a grazing point.  相似文献   

17.
This paper is concerned with the controllability of a system with a time-varying delay. The system to be considered here is described by a linear differential-difference equation of a retarded type, where a time-varying delay is a certain class of a time-varying function. First, the concepts of controllability for linear differential-difference systems with a constant delay, introduced by Weiss (1987), are developed to the system with a time-varying delay. Second, necessary and sufficient conditions for controllability are obtained. Finally, the controllability of a stationary system with a constant delay is treated, including the results of Chyung and Lee (1966).  相似文献   

18.
Analysis of dimensions and tolerances in computer-aided mechanical design   总被引:1,自引:0,他引:1  
The paper sets forth a theory to explain how dimensions and views combine to specify the shape of a mechanical component. It provides a method to determine whether a component is under, over, or exactly defined by a given dimensioning scheme. Measures for assessing the quality of a scheme are proposed. A solution is offered to a problem of tolerancing: given a toleranced dimensioning scheme, find the resulting tolerances between undimensioned parts of a component.  相似文献   

19.
The recognition in image data of viewed patches of spheres, cylinders, and planes in the 3-D world is discussed as a first step to complex object recognition or complex object location and orientation estimation. Accordingly, an image is partitioned into small square windows, each of which is a view of a piece of a sphere, or of a cylinder, or of a plane. Windows are processed in parallel for recognition of content. New concepts and techniques include approximations of the image within a window by 2-D quadric polynomials where each approximation is constrained by one of the hypotheses that the 3-D surface shape seen is either planar, cylindrical, or spherical; a recognizer based upon these approximations to determine whether the object patch viewed is a piece of a sphere, or a piece of a cylinder, or a piece of a plane; lowpass filtering of the image by the approximation. The shape recognition is computationally simple, and for large windows is approximately Bayesian minimum-probability-of-error recognition. These classifications are useful for many purposes. One such purpose is to enable a following processor to use an appropriate estimator to estimate shape, and orientation and location parameters for the 3-D surface seen within a window.  相似文献   

20.
Branching processes of Petri nets   总被引:1,自引:0,他引:1  
Summary The notion of a branching process is introduced, as a formalization of an initial part of a run of a Petri net, including nondeterministic choices. This generalizes the notion of a process in a natural way. It is shown that the set of branching processes of a Petri net is a complete lattice, with respect to the natural notion of partial order. The largest element of this lattice is the unfolding of the Petri net.  相似文献   

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