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101.
102.
An essential problem in the design of holographic algorithms is to decide whether the required signatures can be realized under a suitable basis transformation (SRP). For holographic algorithms with matchgates on domain size 2, , , and have built a systematical theory. In this paper, we reduce SRP on domain size k≥3 to SRP on domain size 2 for holographic algorithms with matchgates on bases of rank 2. Furthermore, we generalize the collapse theorem of [3] to domain size k≥3. 相似文献
103.
Huapeng Yu Yongxin Chang Pei Lu Zhiyong Xu Chengyu Fu Yafei Wang 《Computers & Electrical Engineering》2014
In this paper, we make use of biologically inspired selective attention to improve the efficiency and performance of object detection under clutter. At first, we propose a novel bottom-up attention model. We argue that heuristic feature selection based on bottom-up attention can stably select out invariant and discriminative features. With these selected features, performance of object detection can be improved apparently and stably. Then we propose a novel concept of saccade map based on bottom-up attention to simulate the saccade (eye movements) in vision. Sliding within saccade map to detect object can significantly reduce computational complexity and apparently improve performance because of the effective filtering for distracting information. With these ideas, we present a general framework for object detection through integrating bottom-up attention. Through evaluating on UIUC cars and Weizmann–Shotton horses we show state-of-the-art performance of our object detection model. 相似文献
104.
The O-methylation of phenol with dimethyl carbonate proceeds selectively in the vapor phase over alkali ion exchanged X-zeolites. Thus, a 76% yield of anisole was obtained with a 93% selectivity over NaX at 553 K. The participation of basic sites in the O-methylation is suggested. 相似文献
105.
In this paper, the results of a series of investigations of the effect of morphology on the brittle-ductile transition for HDPE/CaCO3 blends are summarized: (1) It seems the critical ligament thickness increases with increasing matrix toughness; (2) the interphase adhesion is very important for the toughness of HDPE/CaCO3 blends; (3) small particles are more effective than large ones; (4) CaCO3 particle aggregation will reduce toughening efficiency; (5) uniform CaCO3 particle size is more effective than heterogeneous size for the toughening of HDPE. It is expected that a polymer with higher modulus as well as higher toughness will be obtained by appropriately controlling the morphology of HDPE/CaCO3 blends. © 1993 John Wiley & Sons, Inc. 相似文献
106.
Scene-adaptive accurate and fast vertical crowd counting via joint using depth and color information
Reliable and real-time crowd counting is one of the most important tasks in intelligent visual surveillance systems. Most previous works only count passing people based on color information. Owing to the restrictions of color information influences themselves for multimedia processing, they will be affected inevitably by the unpredictable complex environments (e.g. illumination, occlusion, and shadow). To overcome this bottleneck, we propose a new algorithm by multimodal joint information processing for crowd counting. In our method, we use color and depth information together with a ordinary depth camera (e.g. Microsoft Kinect). Specifically, we first detect each head of the passing or still person in the surveillance region with adaptive modulation ability to varying scenes on depth information. Then, we track and count each detected head on color information. The characteristic advantage of our algorithm is that it is scene adaptive, which means the algorithm can be applied into all kinds of different scenes directly without additional conditions. Based on the proposed approach, we have built a practical system for robust and fast crowd counting facing complicated scenes. Extensive experimental results show the effectiveness of our proposed method. 相似文献
107.
Coverage is a fundamental problem in sensor networks. Sensor coverage, which reflects how well a sensor network is monitored by sensors, is an important measure for the quality of service (QoS) that a sensor network can provide. In mobile sensor networks, the mobility of sensor nodes can be utilized to enhance the coverage of the network. Since the movement of sensor nodes will consume much energy, this mobility of sensor nodes should be properly managed by some pre-defined schemes or protocols. By noticing this issue, some existing works have proposed several movement-assisted sensor deployment schemes. These works assume that the target field is a 2-dimensional space. In this paper, we study a generalized case of this problem whereby the target field can be a space which ranges from 1-dimensional to 3-dimensional. Two variations of the movement-assisted sensor deployment problem with different optimization objectives were formulated. We identify a set of basic attributes which can be used as guidelines for designing movement-assisted sensor deployment schemes. Based on these attributes, we propose efficient algorithms for both variants of the movement-assisted sensor deployment problem. 相似文献
108.
The fuzzy object-oriented databases have been proposed to meet the need of dealing with fuzzy as well as complex objects. In this paper, we present a formal fuzzy object-oriented database model. Based on the semantic measure of fuzzy data, we first identify two kinds of fuzzy object redundancies, which are inclusion redundancy and equivalence redundancy, and then define three kinds of merging operation for redundancy removal. On the basis, we define some fuzzy algebraic operations for fuzzy classes and fuzzy objects. Finally, in the paper, we discuss fuzzy querying strategies and give the form of SQL-like fuzzy querying for the fuzzy object-oriented databases. 相似文献
109.
110.
陈甫 《电脑编程技巧与维护》2014,(14):88-90
介绍了一种在BAE3.0上搭建Java-Tomcat类型的微信公众号服务网站的设计思路,以及使用百度开放云上的应用引擎、MySQL数据库、分布式日志服务和百度云存储等相关资源实现微信公众号服务网站的一般过程。 相似文献