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41.
42.
刘天元 《计算机光盘软件与应用》2011,(13)
伴随着Intemet的日益普及,网络应用的蓬勃发展,网络信息资源的安全备受关注。校园网网络中的主机可能会受到非法入侵者的攻击,网络中的敏感数据有可能泄露或被修改,保证网络系统的保密性、完整性、可用性、可控性、可审查性方面具有其重要意义。通过网络拓扑结构和网组技术对校园网网络进行搭建,通过物理、数据等方面的设计对网络安全进行完善是解决上述问题的有效措施。 相似文献
43.
顾勤丰 《计算机光盘软件与应用》2011,(16)
现代楼宇建设理念与以往明显不同,数字信息化与智能化是楼宇建设的关键,楼宇智能化也是建筑学研究的前沿。楼宇智能化将楼宇的房间的距离无限的缩小,不但使人们交流更方便,在安全的防护上也更及时科学。计算机网络在楼宇智能化建设中扮演着技术核心的作用,如何强化计算机网络技术在楼宇智能化建设中的应用是解决提高楼字智能化建设水平的关键。 相似文献
44.
为适应软件开发对业务敏捷性和即时构造性的新要求,采用面向服务的思想,对搭建式软件开发理论和技术进行了研究和实现。与已有的开发模式相比,搭建式开发技术的优势在于它能将工作流、W ebG IS集成到一个面向服务的可视化的搭建平台中。通过电子政务系统的搭建过程表明,搭建式开发技术具有按需、即时、实用的特点,增强了企业的竞争优势。 相似文献
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46.
Multi-scale gist feature manifold for building recognition 总被引:3,自引:0,他引:3
Cairong ZhaoAuthor Vitae Chuancai LiuAuthor VitaeZhihui LaiAuthor Vitae 《Neurocomputing》2011,74(17):2929-2940
Multi-scale gist (MS-gist) feature manifold for building recognition is presented in the paper. It is described as a two-stage model. In the first stage, we extract the multi-scale gist features that represent the structural information of the building images. Since the MS-gist features are extrinsically high dimensional and intrinsically low dimensional, in the second stage, an enhanced fuzzy local maximal marginal embedding (EFLMME) algorithm is proposed to project MS-gist feature manifold to low-dimensional subspace. EFLMME aims to preserve local intra-class geometry and maximize local interclass margin separability of MS-gist feature manifold of different classes at the same time. To evaluate the performance of our proposed model, experiments were carried out on the Sheffield buildings database, compared with the existing works: (a) the visual gist based building recognition model (VGBR) and (b) the hierarchical building recognition model (HBR). Moreover, EFLMME is evaluated on Sheffield buildings database compared with some linear dimensionality reduction methods. The results show that the proposed model is superior to other models in practice of building recognition and can handle the building recognition problem caused by rotations, variant lighting conditions and occlusions very well. 相似文献
47.
对智能建筑的控制网络结构进行研究,给出了采用OPC技术实现系统集成的方案,对OPC服务器的开发进行研究,最后以作者参与的智能大厦系统案例,利用OPC技术通过开发独立OPC服务器将各子系统纳入建筑智能化集成管理平台,达到了系统集成的目的。 相似文献
48.
This study highlights how heuristic evaluation as a usability evaluation method can feed into current building design practice to conform to universal design principles. It provides a definition of universal usability that is applicable to an architectural design context. It takes the seven universal design principles as a set of heuristics and applies an iterative sequence of heuristic evaluation in a shopping mall, aiming to achieve a cost-effective evaluation process. The evaluation was composed of three consecutive sessions. First, five evaluators from different professions were interviewed regarding the construction drawings in terms of universal design principles. Then, each evaluator was asked to perform the predefined task scenarios. In subsequent interviews, the evaluators were asked to re-analyze the construction drawings. The results showed that heuristic evaluation could successfully integrate universal usability into current building design practice in two ways: (i) it promoted an iterative evaluation process combined with multi-sessions rather than relying on one evaluator and on one evaluation session to find the maximum number of usability problems, and (ii) it highlighted the necessity of an interdisciplinary ad hoc committee regarding the heuristic abilities of each profession. A multi-session and interdisciplinary heuristic evaluation method can save both the project budget and the required time, while ensuring a reduced error rate for the universal usage of the built environments. 相似文献
49.
BAIS: A Bayesian Artificial Immune System for the effective handling of building blocks 总被引:1,自引:0,他引:1
Significant progress has been made in theory and design of Artificial Immune Systems (AISs) for solving hard problems accurately. However, an aspect not yet widely addressed by the research reported in the literature is the lack of ability of the AISs to deal effectively with building blocks (partial high-quality solutions coded in the antibody). The available AISs present mechanisms for evolving the population that do not take into account the relationship among the variables of the problem, potentially causing the disruption of high-quality partial solutions. This paper proposes a novel AIS with abilities to identify and properly manipulate building blocks in optimization problems. Instead of using cloning and mutation to generate new individuals, our algorithm builds a probabilistic model representing the joint probability distribution of the promising solutions and, subsequently, uses this model for sampling new solutions. The probabilistic model used is a Bayesian network due to its capability of properly capturing the most relevant interactions among the variables. Therefore, our algorithm, called Bayesian Artificial Immune System (BAIS), represents a significant attempt to improve the performance of immune-inspired algorithms when dealing with building blocks, and hence to solve efficiently hard optimization problems with complex interactions among the variables. The performance of BAIS compares favorably with that produced by contenders such as state-of-the-art Estimation of Distribution Algorithms. 相似文献
50.
在分析SPOT卫星图象阴影与建筑物实际高度关系的基础上,阐述了依据图象建筑物来估算城市建筑物高度的原理和方法,进而探讨了以数据融合为手段的,从SPOT全色图象中准确界定阴影范围的方法,并以此为基础,研究出了一种基于图象阴影特征的城市建筑物高分级及其分布信息自生成技术,在以北京市为例的试验中,建筑物高度分级结果的抽样验证准确率达80%以上,显示出卫星遥感在城市应用方面的巨大潜力。 相似文献