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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
941.
本文针对J2EE技术进行深入研究,对Struts框架进行深入剖析,研究Struts框架的内部结构、运作流程,以及对MVC设计模式的分析研究和对MYSQL数据库进行深入了解,并提出了一个以J2EE为平台,使用Struts框架,引入MVC设计模式的基于J2EE的新闻发布系统。本系统提高了用户获取新闻信息的及时性,使用户能更... 相似文献
942.
Speed up kernel discriminant analysis 总被引:2,自引:0,他引:2
Deng Cai Xiaofei He Jiawei Han 《The VLDB Journal The International Journal on Very Large Data Bases》2011,20(1):21-33
Linear discriminant analysis (LDA) has been a popular method for dimensionality reduction, which preserves class separability. The projection vectors are commonly obtained by maximizing the between-class covariance and simultaneously minimizing the within-class covariance. LDA can be performed either in the original input space or in the reproducing kernel Hilbert space (RKHS) into which data points are mapped, which leads to kernel discriminant analysis (KDA). When the data are highly nonlinear distributed, KDA can achieve better performance than LDA. However, computing the projective functions in KDA involves eigen-decomposition of kernel matrix, which is very expensive when a large number of training samples exist. In this paper, we present a new algorithm for kernel discriminant analysis, called Spectral Regression Kernel Discriminant Analysis (SRKDA). By using spectral graph analysis, SRKDA casts discriminant analysis into a regression framework, which facilitates both efficient computation and the use of regularization techniques. Specifically, SRKDA only needs to solve a set of regularized regression problems, and there is no eigenvector computation involved, which is a huge save of computational cost. The new formulation makes it very easy to develop incremental version of the algorithm, which can fully utilize the computational results of the existing training samples. Moreover, it is easy to produce sparse projections (Sparse KDA) with a L 1-norm regularizer. Extensive experiments on spoken letter, handwritten digit image and face image data demonstrate the effectiveness and efficiency of the proposed algorithm. 相似文献
943.
Szu‐Han Chen Ming‐Dou Ker Tzu‐Ming Wang 《Journal of the Society for Information Display》2011,19(8):539-546
Abstract— A digital time‐modulation pixel memory circuit on glass substrate has been designed and verified for a 3‐μm low‐temperature polysilicon (LTPS) technology. From the experimental results, the proposed circuit can generate 4‐bit digital codes and the corresponding inversion data with a time‐modulation technique. While the liquid‐crystal‐display (LCD) panel operates in the still mode, which means the same image is displayed on the panel, a data driver for an LCD panel is not required to provide the image data of the frame by the proposed pixel memory circuit. This pixel memory circuit can store the frame data and generate its corresponding inversion data to refresh a static image without activating the data driver circuit. Therefore, the power consumption of a data driver can be reduced in the LCD panel. 相似文献
944.
Abstract— Owing to the fast developments of computer networks and color imaging technologies, there is a tendency towards remote proofing in the printing or textile industries. More cases such as cross‐display color matching will occur in the future information society. The problems of color mismatching we usually find in cross‐display devices have been widely discussed today. In this paper, to achieve equivalent color matching between a sRGB monitor and an Adobe RGB monitor, the spatial gamut mapping algorithm (SGMA), which introduces sigmoidal tone mapping, multi‐mapping paths, and unsharp mask (USM) operation into a sRGB color‐management system, is proposed. According to the designs of USM locations, this proposed SGMA can be further developed into pre‐USM, post‐USM, and double‐USM types. Besides, two critical image characteristics, edge map and color histogram, are investigated to establish the relationship between image content and SGMA. The psychophysical experimental results show that double‐USM SGMA obtains better color matching than the other spatial types. 相似文献
945.
With the rapid development of the economy, environmental pollution has become one of the major problems in coastal areas and
in cities along rivers. Real-time observations of the water quality along rivers have been considered to be an efficient way
to control wastewater emission and manage environmental water quality. Traditional ways to observe the ocean environment,
including satellite telemetry, radar, investigation ships, ocean observation stations, etc., are not applicable for water-quality
observations along rivers because of their high cost, poor real-time information, low accuracy, and so on. Based on wireless
sensor networks (WSN), the study reported here proposes a new observation system using underwater multisensory information.
After processing the multisensory data from each sensor, the system transmits it to a hub node through WSN, and then transmits
it to a land data center through a general packet radio service (GPRS) wireless network. In order to check the basic performance
of this system, we completed a node positioning experiment based on a GPS module, and a communication experiment based on
ZigBee. This article reports the design of the hardware and the experimental results. 相似文献
946.
在蚂蚁算法基本规则的启发下,基于移动Agent的分布式路由算法研究(AntNet)的基础上,设计出一种新的基于蚁群代理优化的无线自组网多路径优化的路由协议算法(AdHoc-AntNet).这是一种新的无线自组网的路由算法,其结合蚁群理论和无线自组网本身的特点,对AntNet进行了改进,从而建立更有效的、适合无线自组网的路由协议算法.通过仿真试验表明,与AODV相比该协议在路由开销、平均分组延迟和吞吐量等方面都有明显的改进. 相似文献
947.
948.
研究一种基于手绘草图进行三维建模的方法。将用户界面分为手势区、轮廓区、控制区、信息提示区等。根据手势区输入的手势以及控制区输入的控制信息,对轮廓区输入的二维信息构建三维模型。采用模板匹配的方法识别用户手势,采用容差环的方法识别用户输入的物体轮廓,根据生成的三维数据之间的分层信息构建物体表面三角网格,对物体进行三维建模。 相似文献
949.
根据模糊综合评判法应用的广泛性及现状,提出开发通用的模糊综合评判工具。通过分析需求,建立了系统的功能结构,并通过实例展示了系统的功能。该工具基于Web,利用它,可以针对不同评价问题迅速开发相应的评判系统,且适合群决策,方便而易于使用。 相似文献
950.
基于NS2的AOMDV路由协议的改进与性能仿真 总被引:1,自引:0,他引:1
对AOMDV协议进行了分析,指出了协议存在的不足,利用“一主一备”式路由和抢先式路由对其进行了改进,提出了PAOMDV协议。对NS2(Network Simulator Version2)的分裂对象模型进行了分析,基于NS2实现了AOMDV及PAOMDV路由协议的扩展与仿真。仿真结果表明:在相同的网络环境下,与AOMDV协议相比,PAOMDV协议减少了平均时延、降低了路由发现频率、提高了分组传送率。 相似文献