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81.
82.
Jun Liu Qiong‐Hua Wang Xiao‐Qing Xu Jun Gu 《Journal of the Society for Information Display》2011,19(10):671-674
Abstract— Stereoscopic and autostereoscopic projection‐display systems use projector arrays to present stereoscopic images, and each projector casts one parallax image of a stereoscopic scene. Because of the position shift of the projectors, the parallax images have geometric deformation, which influences the quality of the displayed stereoscopic images. In order to solve this problem, a method based on homography is proposed. The parallax images are pre‐transformed before they are projected, and then the stereoscopic images without geometric distortion can be obtained. An autostereoscopic projection‐display system is developed to present the images with and without calibration. Experimental results show that this method works effectively. 相似文献
83.
围绕车辆调度问题多目标优化这一主题,依据企业现有的GPS定位系统,设计一种基于实数编码和精英保留策略,综合应用外部惩罚函数法的多目标遗传算法.并于其中创新性的引入基因校验算子,避免了重复车次的产生.程序使用Java语言编制,后台数据库使用oracle.实验结果表明,该算法能够充分满足系统硬约束条件,快速收敛于目标约束,完成车辆的优化调度,具有较强的实用价值. 相似文献
84.
85.
Generic Certificateless Encryption Secure Against Malicious-but-Passive KGC Attacks in the Standard Model 总被引:1,自引:0,他引:1
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Despite the large number of certificateless encryption schemes proposed recently, many of them have been found insecure under
a practical attack, called malicious-but-passive KGC (Key Generation Center) attack. In this work we propose the first generic construction of certificateless encryption, which can be proven secure against malicious-but-passive KGC attacks in the standard
model. In order to encrypt a message of any length, we consider the KEM/DEM (key encapsulation mechanism/data encapsulation
mechanism) framework in the certificateless setting, and propose a generic construction of certificateless key encapsulation mechanism (CL-KEM) secure against malicious-but-passive KGC attacks in
the standard model. It is based on an identity-based KEM, a public key encryption and a message authentication code. The high
efficiency of our construction is due to the efficient implementations of these underlying building blocks, and is comparable
to Bentahar et al.’s CL-KEMs, which have only been proven secure under the random oracle model with no consideration of the malicious-but-passive
KGC attack. We also introduce the notion of certificateless tag-based KEM (CL-TKEM), which is an extension of Abe et al.’ s work to the certificateless setting. We show that an efficient CL-TKEM can be constructed by modifying our CL-KEM scheme.
We also show that with a CL-TKEM and a data encapsulation mechanism secure under our proposed security model, an efficient
certificateless hybrid encryption can be constructed by applying Abe et al.'s transformation in the certificateless setting. 相似文献
86.
Jarek Gryz Qiong Wang Xiaoyan Qian Calisto Zuzarte 《Journal of Intelligent Information Systems》2010,34(3):345-366
In recent years more and more queries are generated automatically by query managers/builders with end-users providing only
specific parameters through GUIs. Queries generated automatically can be quite different from queries written by humans. In
particular, they contain non-declarative features, most notorious of which is the CASE expression. Current query optimizers are often ill-prepared for the new types of queries as they do not deal well with procedural
‘insertions’. In this paper, we discuss the inefficiencies of CASE expressions and present several new optimization techniques to address them. We also describe experimental evaluation of
the prototype implemented in DB2 UDB V8.2. 相似文献
87.
88.
A Chinese liquor classification method based on liquid evaporation with one unmodulated metal oxide gas sensor 总被引:1,自引:0,他引:1
Qiong Zhou Shunping Zhang Yuxiao Li Changsheng Xie Huayao Li Xiaohu DingAuthor vitae 《Sensors and actuators. B, Chemical》2011,160(1):483
Electronic nose has been widely used in the classification of liquid samples, such as vinegars, wines and liquors, which have complex components. The difficulty of these classifications is how to get the information of the trace components in these samples. In this paper a method for liquor recognition based on liquid evaporation was presented. This method makes use of the distinct evaporation characteristics of different components in liquor samples. And during the evaporation process, one metal oxide gas sensor was used to detect the headspace of liquor samples for classification. Due to the distinct evaporation characteristics of different components, volatile compounds in the headspace evaporating from samples would change with the testing time. Meanwhile, the gas sensor would respond to these volatile compounds. Accordingly, more information of liquor samples during evaporation may be acquired with the proposed method. To verify the performance of this method, 8 different Chinese liquors with 50% alcohol for comparison were tested under the method. The results showed that the evaporation characteristics of these liquor samples were quite distinct. The correct classification accuracy of discriminant function analysis was 100%, which indicated this method may be a simple and effective way for complex-component liquid sample analysis. 相似文献
89.
针对分布资源管理中的信息服务问题,通过建立统一的资源信息模型,设计并实现能够集中、统一提供信息服务的资源信息服务器,测试和分析该资源信息服务器对整个系统性能的影响。结果证明能够提高整个分布式系统的性能。 相似文献
90.
针对极限学习机(ELM) 网络结构优化问题, 提出一种改进的灵敏度剪枝ELM(ImSAP-ELM). ImSAP-ELM 将??2 正则化因子引入SAP-ELM 中, 采用留一准则确定最优隐节点数. 推导基于奇异值分解的输出权重计算公式, 避免矩阵奇异导致求解无效的问题. 将ImSAP-ELM 用于故障预测, 利用多组同类型故障数据建立多个ImSAP-ELM 模型, 基于加权思想融合不同ImSAP-ELM 的预测值. 某型无人机发射机实例表明, 相比于ELM、OP-ELM (最优剪枝ELM) 和SAP-ELM, ImSAP-ELM 耗时最高, 但是ImSAP-ELM 的预测误差小于其他3 种方法.
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