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91.
Cheng Reynold Kao Ben Kwan Alan Prabhakar Sunil Tu Yicheng 《Knowledge and Data Engineering, IEEE Transactions on》2010,22(2):234-248
The idea of allowing query users to relax their correctness requirements in order to improve performance of a data stream management system (e.g., location-based services and sensor networks) has been recently studied. By exploiting the maximum error (or tolerance) allowed in query answers, algorithms for reducing the use of system resources have been developed. In most of these works, however, query tolerance is expressed as a numerical value, which may be difficult to specify. We observe that in many situations, users may not be concerned with the actual value of an answer, but rather which object satisfies a query (e.g., "who is my nearest neighbor?”). In particular, an entity-based query returns only the names of objects that satisfy the query. For these queries, it is possible to specify a tolerance that is "nonvalue-based.” In this paper, we study fraction-based tolerance, a type of nonvalue-based tolerance, where a user specifies the maximum fractions of a query answer that can be false positives and false negatives. We develop fraction-based tolerance for two major classes of entity-based queries: 1) nonrank-based query (e.g., range queries) and 2) rank-based query (e.g., k-nearest-neighbor queries). These definitions provide users with an alternative to specify the maximum tolerance allowed in their answers. We further investigate how these definitions can be exploited in a distributed stream environment. We design adaptive filter algorithms that allow updates be dropped conditionally at the data stream sources without affecting the overall query correctness. Extensive experimental results show that our protocols reduce the use of network and energy resources significantly. 相似文献
92.
Lili Wang Yan Tu Li Chen Panpan Zhang Kees Teunissen Ingrid Heynderickx 《Journal of the Society for Information Display》2010,18(6):405-414
Abstract— One of the most annoying distortions in (auto)stereoscopic displays is probably cross‐talk, visible as double edges, which is mainly caused by an imperfect separation of left‐ and right‐eye images. For different types of three‐dimensional (3‐D) displays, cross‐talk is caused by different origins, which could result in different levels of perceived image distortion. To evaluate the influence of (auto)stereoscopic display technology on cross‐talk perception, optical measurements and subjective assessments were performed with three different types of 3‐D displays. It is shown with natural still images that the 3‐D display technology with the lowest luminance and contrast level tolerates the highest level of cross‐talk, while still maintaining an acceptable image‐quality level. 相似文献
93.
提出了万能式断路器综合性能检测系统设计中的几个关键技术问题并给出解决方案;为了兼容测试不同类别、不同电流规格的万能式断路器产品,系统将虚拟仪器技术与计算机控制技术相结合,采用三级变换结构和闭环控制方式提高三相大电流发生器的输出精度,设计水平轴向滑动式气动夹具解决不同外形尺寸断路器的不同接线方式问题,软件设计采用分层结构和基于配置文件的设计方法;实际应用表明,这套方案可以满足万能式断路器综合性能检测系统对多类别多规格产品的测试要求. 相似文献
94.
提出一种基于WEB嵌入式自适应智能控制系统设计方案,提供了各组成模块软硬件的详细设计与具体实现;系统采用主流的S3C2410作为处理器,通过I2C总线实现各硬部件的连接;开发的嵌入式WEB服务器模块,使得用户能够对温度传感器读数进行互联网远程监测和多路数字、模拟量输出智能控制;并且神经网络模块能够自适应地学习和控制温度读数与制冷设备输出数之间的关系。实验结果显示改进后的Hopfield算法的收敛性和记忆性得到了提高,并使该系统具有较大的应用价值。 相似文献
95.
The fire signals are much weaker in low oxygen concentration and low pressure environment such as Tibet. Fire detectors which were calibrated in correlating standard conditions cannot work well in such condition. This paper presents a synthesis method of GM(1, 1) grey prediction model and adaptive neuro-fuzzy inference system (ANFIS) in advance to detect fire and to make it work in the environment. The theoretical analysis of the algorithm and experimental evaluation in Tibet are presented. In this process, the grey GM(1, 1) predict model can anticipate the development of fire signals without any assumption, thus allowing earlier fire alarm than traditional fire detection equipments, meanwhile, ANFIS can make sure the data processing more accurate to avoid false alarms. This work will supply useful suggestions with the fire detectors design in low ambient pressure and low oxygen concentration such as Tibet, etc. 相似文献
96.
97.
This paper reports a work that was intended to reveal the connection between topics investigated by conference papers and journal papers. This work selected hundreds of papers in data mining and information retrieval from well-known databases and showed that the topics covered by conference papers in a year often leads to similar topics covered by journal papers in the subsequent year and vice versa. This study used some existing algorithms and combination of these algorithms to proposed a new detective procedure for the researchers to detect the new trend and get the academic intelligence from conferences and journals.The goal of this research is fourfold: First, the research investigates if the conference papers’ themes lead the journal papers’. Second, the research examines how the new research themes can be identified from the conference papers. Third, the research looks at a specific area such as information retrieval and data mining as an illustration. Fourth, the research studies any inconsistencies of the correlation between the conference papers and the journal papers.This study explores the connections between the academic publications. The methodologies of information retrieval and data mining can be exploited to discover the relationships between published papers among all topics. By discovering the connections between conference papers and journal papers, researchers can improve the effectiveness of their research by identifying academic intelligence.This study discusses how conference papers and journal papers are related. The topics of conference papers are identified to determine whether they represent new trend discussed in journal papers. An automatic examination procedure based on information retrieval and data mining is also proposed to minimize the time and human resources required to predict further research developments. This study develops a new procedure and collects a dataset to verify those problems. Analytical results demonstrate that the conference papers submitted to journals papers are similar each year. Conference papers certainly affect the journal papers published over three years. About 87.23% of data points from papers published in 1991–2007 support our assumption. The research is intended to help researchers identify new trend in their research fields, and focus on the urgent topics. This is particularly valuable for new researchers in their field, or those who wish to perform cross-domain studies. 相似文献
98.
In this paper, we present a general framework, using a systems science approach, for developing a decision support system (DSS) for fisheries management. Decision support systems are quantitative tools for managers to evaluate outcomes of their policies prior to implementation. Our fishery model considers multiple stocks and fisheries simultaneously in balancing catch among targeted and protected fish abundances. Since in the Northeastern US multispecies fishery the distribution of abundance, catch-per-unit-effort and bycatch vary geographically, we focus on a spatial management approach to address their spatial variability. The core component of this DSS applies operations research techniques of simulation and optimization to determine the optimal inter-annual and intra-annual fishing plans in terms of fishing efforts in each sub-area and the time period. The result is the recommended amount to catch from each fish species at each sub-area at any time period so that while management objectives for sustainability of fish stocks are satisfied, the value of landings is maximized. The graphical user interface of the proposed DSS helps users to define inputs, to set constraints and sub-area boundaries, and to visualize the outcomes. 相似文献
99.
100.
面向嵌入式零代码基础使用者和低成本开发者,搭建了一个基于STM32的软硬件一体化编程的流程图化的嵌入式系统开发平台.该平台采用STM32作为硬件载体,用QT跨平台C++图形用户界面搭建简单易懂的流程图操作界面.硬件框图界面能驱动嵌入式设备,用编译软件封装功能模块放置功能编辑盒,通过命令行调用编译器,调用外部烧录软件完成下载,代码查看器可直观监视编译全过程.测试结果表明,该平台可方便、快捷解决编程问题. 相似文献