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991.
In the paper, a novel two‐level algorithm of time‐series change detection is presented. In the first level, to identify non‐stationary sequences in a processed signal, preliminary detection of events is performed with a short‐term prediction comparison. In the second stage, to confirm the changes detected in the first level, a similarity method aimed at identification of unique changes is employed. The detection of changes in a non‐stationary time series is discussed, implemented algorithms are described and the results produced on a sample four financial time series are shown. General conditions for implementing the proposed algorithm as an immune‐like event detector are discussed.  相似文献   
992.
Intelligent tutoring and personalization are considered as the two most important factors in the research of learning systems and environments. An effective tool that can be used to improve problem‐solving ability is an Intelligent Tutoring System which is capable of mimicking a human tutor's actions in implementing a one‐to‐one personalized and adaptive teaching. In this paper, a novel Flowchart‐based Intelligent Tutoring System (FITS) is proposed benefiting from Bayesian networks for the process of decision making so as to aid students in problem‐solving activities and learning computer programming. FITS not only takes full advantage of Bayesian networks, but also benefits from a multi‐agent system using an automatic text‐to‐flowchart conversion approach for engaging novice programmers in flowchart development with the aim of improving their problem‐solving skills. In the end, in order to investigate the efficacy of FITS in problem‐solving ability acquisition, a quasi‐experimental design was adopted by this research. According to the results, students in the FITS group experienced better improvement in their problem‐solving abilities than those in the control group. Moreover, with regard to the improvement of a user's problem‐solving ability, FITS has shown to be considerably effective for students with different levels of prior knowledge, especially for those with a lower level of prior knowledge.  相似文献   
993.
In this paper, we consider cluster analysis based on T‐transitive interval‐valued fuzzy relations. A fuzzy relation with its partitional tree for obtaining an agglomerative hierarchical clustering has been studied and applied. In general, these fuzzy‐relation‐based clustering approaches are based on real‐valued memberships of fuzzy relations. Since interval‐valued memberships may be better than real‐valued memberships to represent higher order imprecision and vagueness for human perception, in this paper we first extend fuzzy relations to interval‐valued fuzzy relations and then construct a clustering algorithm based on the proposed T‐transitive interval‐valued fuzzy relations. We use two examples to demonstrate the efficiency and usefulness of the proposed method. In practical application, we apply the proposed clustering method to performance evaluations for academic departments of higher education by using actual engineering school data in Taiwan.  相似文献   
994.
995.
In this paper, we characterize all weakly smooth uninorms (i.e., uninorms with smooth underlying operators) defined on a finite chain. It is proved that any such uninorm is determined by three unary functions and vice versa. As a by‐product, we obtain the characterizations of smooth t‐norms, smooth t‐conorms through additive generators and show that on a finite chain, there exists no counterpart of the class of uninorms continuous in ]0, 1[2.  相似文献   
996.
Recently, Kim and Bell ( 2011 ) developed a revenue managemnent pricing model with price‐driven substitution. The authors considered production decisions under unlimited production capacity and investigated the impact of price‐driven substitution on a firm's pricing and production decisions. The authors modeled the consumer demands for each market segment as linear additive demand function based on exogenous variables, where demand substitution occurred as a function of price differences between the two products. In this article, we extend this work to examine the impact of a production capacity constraint on the firm's joint pricing and inventory decisions. Based on this extended model, we investigate the impact of price‐driven substitution on a firm's pricing and production decisions where there is a limit on total capacity. We show how revenue managers should adjust prices and production levels to take into account price‐driven substitution under a capacity constraint setting. Both deterministic and stochastic models are developed, and the impact of price‐driven substitution and a capacity constraint on the optimal prices, production levels, and revenues is illustrated.  相似文献   
997.
This study uses the three‐stage data envelopment analysis (DEA) model to explore the true managerial efficiency of the banking firms in Taiwan, Hong Kong, and Mainland China. The empirical results indicate that the environmental conditions have a significant impact on banking efficiency. When the country‐specific situations are important factors in explaining efficiency difference, the common frontier estimates obtained by neglecting those factors can generate biased and overestimated inefficiency levels. With findings obtained from the slack variable analyses, the current study can provide inefficient banks with ways to reduce their input waste through the adjustment of input allocations. The findings also confirm the importance of the three‐stage DEA and its applications in determining the true managerial efficiencies of banks. Without the three‐stage DEA, the management could be misguided when making strategic decisions and conducting inappropriate resource allocation.  相似文献   
998.
ARM Cortex-M0+是2012年新发布的一款将逐步8位/16位微处理器市场的32位低功耗、高性能处理器,规范的汇编框架与样例是一个新微处理器深层次应用开发的基础。鉴于目前ARM Cortex-M0+的汇编程序资料与样例程序十分匮乏,加之汇编设计的复杂性,在充分分析ARM Cortex-M0+汇编寻址方式与指令系统的基础上,以Freescale半导体公司于2013年正式发布的ARM Cortex-M0+KL系列MCU为蓝本,基于CW10.3开发环境,结合软件构件设计思想,提出构件化ARM Cortex-M0+汇编框架,并编制GPIO汇编构件,给出应用实例。旨在降低读者学习ARM Cortex-M0+汇编程序的难度,完成第一个ARM Cortex-M0+规范化汇编程序。  相似文献   
999.
李伟  张庭  姜力 《传感器与微系统》2015,(2):122-124,146
为了满足生机电一体化仿人假手的控制需求,提出了基于FPGA的仿人假手电气控制系统设计方案。采用模块化设计思想,由FPGA构成的主控芯片模块便于功能拓展与二次开发;由DSP构成的手指运动控制模块、肌电信号采集模块、电刺激模块、USG接口模块和电池管理模块均可独立工作,与主控芯片模块间通过通用接口连接。系统集成度高,可完全放置于假手内部。应用该控制系统在HIT V代手上进行多指抓取实验,实验结果证明其工作效果良好。  相似文献   
1000.
基于接纳控制的智能电网需求响应   总被引:1,自引:0,他引:1  
采用效用函数刻画用户的用电满意度, 将需求响应问题建模为一类凸优化问题. 针对电力供应商的供电量不能满足用户最小用电需求的问题, 结合分布式用电量调度和实定价, 设计两类接纳控制算法. 仿真结果表明, 通过接纳控制, 满足了购电用户的最小用电需求, 保证了用户的用电质量, 能够实现电网的供需平衡.  相似文献   
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