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71.
Transmission pricing has become a major issue in the discussions about the deregulated electricity markets.Consequently,open access to the transmission system is one of the basic topics to allow competition among participants in the energy market.Transmission costs have an important impact on relative competition among participants in the energy market as well as on short-and long-term economic efficiencies of the whole electricity industry,although they represent only close to 10% of the energy market price.This paper deals with the design and tests of a transmission pricing method based on the optimal circuit prices derived from the economically adapted network(EAN).Prices derived from the EAN have the advantage of being in tune with the maximum revenue allowed to the owner of transmission assets and simplifying the optimal allocation of transmission costs among participants.Beginning from the conceptual design,the proposed method is tested on a three-bus network and on the IEEE 24-bus reliability test system. 相似文献
72.
陈泽婷 《电脑与微电子技术》2012,(5):77-80
针对传统的单个LED显示屏的控制的问题.开发基于ARM器件使用触摸屏技术和Zig—Bee无线传输技术的校园LED公告板远程控制系统。 相似文献
73.
Key areas of robot agility include methods that increase capability and flexibility of industrial robots and facilitate robot re-tasking. Manual guidance can achieve robot agility effectively, provided that a safe and smooth interaction is guaranteed when the user exerts an external force on the end effector. We approach this by designing an adaptive admittance law that can adjust its parameters to modify the robot compliance in critical areas of the workspace, such as near and on configuration singularities, joint limits, and workspace limits, for a smooth and safe operation. Experimental validation was done with two tests: a constraint activation test and a 3D shape tracing task. In the first one, we validate the proper response to constraints and in the second one, we compare the proposed approach with different admittance parameter tuning strategies using a drawing task where the user is asked to guide the robot to trace a 3D profile with an accuracy or speed directive and evaluate performance considering path length error and execution time as metrics, and a questionnaire for user perception. Results show that appropriate response to individual and simultaneous activation of the aforementioned constraints for a safe and intuitive manual guidance interaction is achieved and that the proposed parameter tuning strategy has better performance in terms of accuracy, execution time, and subjective evaluation of users. 相似文献
74.
This paper proposes a new method for calculating a bound on the gain of a system comprising a linear time invariant part and a static nonlinear part, which is odd, bounded, zero at zero and has a restriction on its slope. The nonlinear part is also assumed to be sector bounded, with the sector bound being (possibly) different from that implied by the slope restriction. The computation of the gain bound is found by solving a set of linear matrix inequalities, which arise from an integral quadratic constraint formulation of a multiplier problem involving both Zames‐Falb and Popov multipliers. Examples illustrate the effectiveness of the results, and comparisons are made against the state‐of‐the‐art. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
75.
Finding a path that satisfies multiple Quality-of-Service (QoS) constraints is vital to the deployment of current emerged services. However, existing algorithms are not very efficient and effective at finding such a path. Moreover, few works focus on three or more QoS constraints. In this paper, we present an enhanced version of fully polynomial time approximation scheme (EFPTAS) for multiconstrainted path optimal (MCOP) problem. Specifically, we make four major contributions. We first allow the proposed algorithm to construct an auxiliary graph, through which the QoS parameters on each of the finding path can be guaranteed not to exceed the given constraints. Then we adopt a concept, called nonlinear definition of path constraints in EFPTAS for reducing both time and space complexity. Also, we enable EFPTAS to run iteratively to facilitate a progressive refinement of the finding result. In addition to these, we identify some “deployment” issues for proposed algorithm, the essential steps that how and when the EFPTAS takes place are presented. By analyzing the proposed algorithm theoretically, we find that the presented EFPTAS can find a (1+ε)-approximation path in the network with time complexity O(|E||V|/ε) (where |E| is the number of edges and |V| is the number of nodes), which outperforms the previous best-known algorithm for MCOP. We conduct an extensive comparison between the algorithm presented in this paper and previous best-known study experimentally, our results indicate that EFPTAS can find a path with low complexity and preferable quality. 相似文献
76.
Xiuming Huang 《Machine Translation》1988,3(2):101-120
This paper concerns the resolution of lexical ambiguity in a machine translation environment. We describe the integration of principles of selection restrictions. Preference Semantics, and intelligent relaxation of constraints in handling lexical ambiguity. The approach differs from many previous MT systems in that it is more powerful than brute force systems, while more realistic than systems that assume a large degree of coded encyclopedia information for full understanding. 相似文献
77.
网络数据单向传输问题在人类生产生活中具有十分广泛的应用,但目前对该问题还没有较为完善的解决方案。在分析该问题几种方案存在不足的同时,提出并实现了一种全新的基于图像识别原理的网络数据单向传输解决方案。实验证明,这种新的解决方案在具备完全物理隔离优点的同时,具有实现简单、便于推广的特点,在一定程度上优于现有常用的解决方案。 相似文献
78.
A model of a linear digital communication system is introduced and adaptive equalization in general is explained. A five-tap transversal equalizer is designed, breadboarded and tested in a 60 Mb/s burst mode modem in a quasi-linear and a non-linear channel under the following configurations:
- 1 Parabolic, linear and combination of parabolic and linear delay distortions were inserted after the non-linearity (TWTA).
- 2 Case 1 was repeated with distortions inserted before the non-linearity.
79.
针对块对角表示(block diagonal representation, BDR)子空间聚类算法在对子空间重叠的高维数据聚类时效果较差的问题,提出成对约束的块对角子空间聚类(constrained subspace clustering with block diagonal representation, CBDR)算法,设计主动式学习策略,获取用户提供的少量数据点成对信息,以改进BDR算法的性能,给出CBDR算法的目标函数和求解过程。在测试集上的试验结果表明,CBDR算法的聚类错误率和归一化互信息指标比BDR和SBDR(structured block diagonal representation)算法好,而且主动式选取点对方法优于随机选取点对方法,使用少于5‰的约束信息可降低BDR的聚类错误率达到5%以上。 相似文献
80.
为解决设计模式挖掘正确率较低的问题, 提出一种带特征指标约束描述的设计模式分类挖掘方法。归纳了47种特征指标, 给出了设计模式约束定义, 对设计模式特征进行了描述, 以Adapter模式、Command模式、Factory Method模式为例, 分结构型、行为型与创建型3类挖掘设计模式, 设计了3个基准系统与4个经典系统的设计模式挖掘试验。试验结果表明, 本研究方法对基准系统的Adapter模式、Command模式、Factory Method模式挖掘正确率为96.13%、91.67%、72.23%, 对经典系统挖掘正确率分别为84.3%、81.26%、73.17%, 与传统方法比较, 本研究方法取得了较好的效果。 相似文献