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991.
John J. McCann 《Journal of the Society for Information Display》2007,15(9):709-719
Abstract— High‐dynamic‐range (HDR) image capture and display has become an important engineering topic. The discipline of reproducing scenes with a high range of luminances has a five‐century history that includes painting, photography, electronic imaging, and image processing. HDR images are superior to conventional images. There are two fundamental scientific issues that control HDR image capture and reproduction. The first is the range of information that can be measured using different techniques. The second is the range of image information that can be utilized by humans. Optical veiling glare severely limits the range of luminance that can be captured and seen. It is the improved quantization of digital data and the preservation of the scene's spatial information that causes the improvement in quality in HDR reproductions. 相似文献
992.
993.
根据元胞自动机(CA)的基本理论及其在城市动态演化模拟中的应用,提出了新的电力负荷空间分布预测方法。该方法从元胞自动机的基本定义出发,研究了CA理论对于电力负荷空间分布预测的适用性,提出了电力负荷元胞、元胞样区、元胞时空数据库、样本数据库的概念,制定了考虑多种相关因素的负荷元胞转换规则和相关参数,并进行了简单的试验。算例结果说明了该方法的可行性及其预测结果的合理性。 相似文献
994.
堆石坝填筑碾压质量采用事中和事后双控。事中碾压参数往往不能在全工作仓面上100%满足控制要求,且受坝料性质不均匀的影响,即便是相同的碾压参数,也可能会导致不同的压实质量。事后试坑检测采用有限个测点,难以客观反映整个施工仓面的压实质量;若单纯采用压实连续检测指标(如CV)控制,其与坝料压实质量之间也存在一定误差。文章利用大坝填筑碾压质量实时监控技术,在动态采集碾压参数和压实连续检测指标CV的基础上,采用Dempster-Shafer(D-S)证据理论,提出了一种综合考虑事中碾压参数、事后CV的压实质量模糊综合评价方法。此外,为了保证碾压区域无明显连续薄弱区,通过DBSCAN空间聚类分析,提出等效连续薄弱面积的概念,对压实质量薄弱区域空间分布进行定量评价。实例分析表明,此方法可以有效避免单独事中或事后评估的片面性,提高压实质量评估的全面性,为高堆石坝施工质量控制提供一种新的手段。 相似文献
995.
Several researchers have identified the need to count on presence awareness in ubiquitous systems that support mobile activities, particularly when these systems are used to perform loosely-coupled mobile work. In such a work style, mobile users conduct face-to-face on-demand interactions, therefore counting on awareness information about the position and availability of potential collaborators becomes mandatory for these applications. Most proposed solutions that provide user presence awareness involve centralized components, have reusability limitations, or simply address a part of that service. This article presents a lightweight and fully distributed middleware named Moware, which allows developers to embed presence awareness services in mobile ubiquitous systems in a simple way. The article also describes the Moware architecture, its main components and strategies used to deal with several aspects of the presence awareness support. These design strategies can be reused by software designers to provide presence awareness capabilities into middleware and specific software applications. Moware services were embedded in a mobile ubiquitous system that supports inspectors during the construction inspection process. The preliminary results indicate that the middleware was easy to use for developers, and its services were useful for the end-users. 相似文献
996.
In the densely-populated urban areas, pedestrian flows often cross each other and congestion is caused. The congestion makes us feel uncomfortable and sometimes leads to pedestrian accidents. To reduce the congestion or the risk of accidents, it is required to control the swarm behavior of pedestrian flows. This paper proposes modeling and controlling method of the crossing pedestrian flows. In the social/urban engineering, it is well known that the swarm behavior with a diagonal stripe pattern emerges in the crossing area of the flows. This is a self-organized phenomenon caused by the local collision avoidance effect of the pedestrians. To control the macroscopic behavior of the flows, we utilize this self-organized phenomenon. Firstly, we propose the continuum model of the crossing pedestrian flows. In the continuum model, the dynamic change of the congestion in the diagonal stripe pattern is simulated as the density. Secondly, the novel control method to improve average flow velocity is proposed based on the model. The proposed method utilizes the dynamic interaction between the diagonal stripe pattern and guides, who are moving in the flows. The authors derive the control algorithm through an analysis on the temporal and spatial frequencies of the crossing flows. The validity is verified with simulations using the continuum model. Moreover, we apply the proposed method to the particle model, assuming the actual pedestrians. 相似文献
997.
Derick Leony Pedro J. Muñoz-Merino Abelardo Pardo Carlos Delgado Kloos 《Expert systems with applications》2013,40(13):5093-5100
One of the challenges of intelligent systems for education is to use low-level data collected in computer environments in the form of events or interactions to infer information with high-level significance using artificial intelligence techniques, and present it through visualizations in a meaningful and effective way. Among this information, emotional data is gaining track in by instructors in their educational activities. Many benefits can be obtained if an intelligent systems can bring teachers with knowledge about their learner’s emotions, learning causes, and learning relationships with emotions. In this paper, we propose and justify a set of visualizations for an intelligent system to provide awareness about the emotions of the learners to the instructor based on the learners’ interactions in their computers. We apply these learner’s affective visualizations in a programming course at University level with more than 300 students, and analyze and interpret the student’s emotional results in connection with the learning process. 相似文献
998.
999.
用水效率的提高是在用水总量一定的前提下,保障和行业用水需求和经济社会良性发展的重要手段。通过对广东省1980-2011年用水效率指标在年度和地市空间上的变化趋势和变化规律进行分析,结果表明,总用水量年均增长率为1.08%,人均水资源量年均递减率为2.90%,人均用水量年均递减率为1.16%,人均综合用水量年均递减率为1.75%,都与总用水量呈反向变化的特征,而耗水量和农田灌溉亩均用水指标年均变化率分别为0.76%和-0.21%,变化幅度相对较小,说明用水效率整体提高并不明显。并分析了各市不同用水阶段单位农业增加值用水量变化,以2005-2010年最快,年均变化率为-8.52%,同时表现出区域和年际变化差异较大,年灌溉用水效率较低的特点。 相似文献
1000.
现有的电网运行管理手段已很难适应现代化电网生产建设和发展的需要,而GIS技术凭借其强大的空间信息管理分析能力以及可视化的空间信息展现能力迅速适应了电力信息平台的建设.首先介绍了WebGIS的相关技术并分析了ArcGIS Server的体系结构.通过对系统的体系结构,空间数据库,以及各功能模块的详细设计构建了一个新的基于Ar-cGIS Server的WebGIS应用系统.在对系统各项关键技术功能(空间查询,电力故障定位等)的阐述后,以山西省输电线路实时监测系统模拟运行环境为例,进行了各项功能的基本测试,证明了系统具有良好的实用性和稳定性,满足了电网信息化平台建设的需要. 相似文献