基于复杂网络理论的计算机网络拓扑分析

从复杂网络理论、计算机网络拓扑技术、复杂网络理论在计算机网络拓扑中的应用等方面,具体阐述了复杂网络理论基础上的计算机网络拓扑技术。     

Computer Support for Implementation of a Systemic Approach to Water Conflict Resolution

Abstract

Water is an important factor in conflicts among stakeholders at the local, regional, and even international level. Water conflicts have taken many forms, but they almost always arise from the fact that the freshwater resources of the world are not partitioned to match the political borders, nor are they evenly distributed in space and time. Two or more countries share the watersheds of 261 major rivers and nearly half of the land area of the world is in international river basins. Water has been used as a military and political goal. Water has been a weapon of war, and water systems have been targets during the war. A systemic approach has been taken in this research to approach resolution of conflicts over water. By helping stakeholders to explore and resolve the underlying structural causes of conflict our approach offers a significant opportunity for its resolution. We define the five main functional activities for assisting the conflict resolution process as: (i) communication; (ii) problem formulation; (iii) data gathering and information generation; (iv) information sharing; and (v) evaluation of consequences. A computerized technical support is developed in the form of the Conflict Resolution Support System (CRSS) for implementation of a systemic approach to water conflicts. Its principal components include an artificial intelligence-based communication system, a database management system, and a model base management system. At this stage of the development, the model base management system consists of tools for multipurpose reservoir operation, river flow routing, multi-criteria decision-making, spatial data analysis, and other general utilities. A hypothetical river basin with potential conflict between stakeholders with respect to water sharing and flood control is used to demonstrate the utility of the new approach and the computer system developed for its implementation.     

一种面向任务优化的多核心星务管理系统设计

为进一步提升小卫星的数据处理能力,对星载电子系统进行了优化设计.在现有可重构星务管理系统的基础上,提出一种多核心处理器星务管理系统设计方法.结合多核心处理器特点,按照硬件资源以及任务模式对星务管理系统的传统任务划分方法进行优化,将单一处理器任务集中处理的模式分解为主、协处理器双核任务处理模式.与哈尔滨工业大学试验卫星三号星载计算机的功能对比表明,多核心可重构星务管理系统在运算速度、控制计算精度方面优于传统的星务管理系统处理方式,有能力替代现有的星载计算机成为未来微型航天器的核心.     

基于卡尔曼滤波的ECoG信号去噪方法研究

脑电信号反映了生物体的大脑活动,在采集和处理过程中极易受到各种噪声的干扰,如眨眼、快速眼动、心电、肌电等,这些噪声给脑电信号的分析处理带来了很大的困难。本文提出了卡尔曼滤波模型和模型参数估计的方法,将其应用于脑电ECoG信号去噪预处理。实验所用的数据是公开的脑机接口竞赛实验数据（BCI Competition Ⅲ dataset Ⅰ）,分类正确率为92%。实验结果表明通过本方法去噪预处理后,分类正确率比竞赛第一名高,并且优于小波去噪与谱减法等预处理方法。     

基于NSCT和遗传算法的SAR图像和多光谱图像融合

合成孔径雷达(SAR)图像与多光谱图像成像机理和光谱特性差异较大,一般的融合方法很难取得满意的融合结果。文章提出了一种基于Nonsuosampled Contourlet transform(NSCT)和遗传算法的融合算法,首先将经过预处理后的图像进行NSCT分解,低频系数采取区域信息熵最大的准则融合;高频子带计算区域相关性,对相关性在不同阈值范围内的系数进行融合,阈值的选取采用遗传算法进行搜索;最后对融合系数进行NSCT逆变换,得到融合结果。仿真结果表明该算法显著优于基于像素点和基于区域的融合方法。     

混合关键度驱动的实时调度研究

针对当前运行于不可预测开放环境下的嵌入式多使命复杂关键型系统,需要减少运行成本和处理不可预测工作负载情况的问题,文章提出一种混合关键度驱动的非对称式过载保护最小空闲调度策略。系统过载时,为共享同一处理器的不同关键度任务提供非对称式保护,禁止低关键度任务干扰高关键度任务,完全避免了传统的"关键度反转"问题。在恢复暂时阻塞的不同关键度任务时,在速率单调调度的基础上,引入关键度主导的截止期驱动动态调度策略,可使潜在处理器利用率达到100%。实验结果表明,这种新算法的综合性能优于当前已有的混合关键度任务调度算法。     

鉴别式多核手跟踪

快速运动、背景混杂及手的特殊性为传统的核目标跟踪技术提出了挑战.文中提出一种鉴别式颜色子空间选择和多核校正机制的核跟踪方法.首先基于前景背景建模,通过鉴别函数选取最优鉴别式颜色子空间集,再基于训练的肤色模型保留高置信子空间表征目标.其次,为适应尺度变化和快速运动,基于多核快速估计相似度表面以校正初始核位置,迭代定位目标.实验表明,融合二者的跟踪器在有效性和速度上都实现了满意的性能,满足实时性需要.     

Interactive augmented reality system for enhancing library instruction in elementary schools

Due to limited budgets and manpower, most elementary schools in Taiwan do not plan or provide library instruction for students. Although students can use libraries, they typically lack the knowledge needed to use library resources effectively. Consequently, students have difficulty finding the books they need and can easily become overwhelmed by the massive amount of information in libraries. Computer-assisted instruction for teaching basic library skills to large numbers of students is an appealing method. Particularly, developing augmented reality (AR) technologies for learning have garnered considerable attention in education research. Many researchers and scholars believe that integrating teaching and AR enhances student learning performance and motivation. This work develops an educational AR system based on situated learning theory, and applies innovative augmented reality interactive technology to a library’s learning environment. Student library knowledge can be enhanced via the proposed augmented reality library instruction system (ARLIS). Experimental results demonstrate that student learning performance is improved significantly by using the proposed ARLIS. Moreover, this work demonstrates that using the proposed ARLIS for library instruction results in the same learning performance as conventional librarian instruction and there is no gender difference on learning performance between the proposed ARLIS and conventional librarian instruction. Moreover, the proposed library instruction system overcomes shortcomings of personal teaching skills of librarians that may adversely affect student learning performance by conveying the same learning content to all students. Additionally, the proposed system results in better learning performance for learners with the field-dependent cognitive style than learners with the field-independent cognitive style. Further, the proposed system provides more benefits in terms of library skills of application and comprehension than conventional librarian instruction. Moreover, the learning performance of students is not affected by their gaming skills. Therefore, student gaming skills do not need to be considered when adopting the proposed system in library instruction programs.     

The influence of virtual presence: Effects on experienced cognitive load and learning outcomes in educational computer games

Does the immersive design of an educational gaming environment affect learners’ virtual presence and how much do they learn? Does virtual presence affect learning? This study tries to answer these questions by examining the differences in virtual presence and learning outcomes in two different computer-based multimedia environments: a gaming environment with high immersive design vs. hypertext learning environment with low immersive design. As the main focus, the effect of virtual presence on learning is also explained and tested. By identifying virtual presence as a variable that may determine learning, it is argued that computer gaming environments present a new challenge for researchers to investigate, particularly, the effects of virtual presence on the immersive design of games in order to help designers to predict which instructional configurations will maximize learning performance. In general, results revealed that the high-immersive gaming environment leads to the strongest form of virtual presence but also decreased learning. Although regression analyses indicate that virtual presence positively influences trivial- and non-trivial learning outcomes, learners who learned in a low-immersive environment outperformed the gaming group. A mediation analysis showed that the relation between virtual presence and non-trivial learning outcomes is partly mediated through increased cognitive load.     

Differences in children and adolescents' ability of reporting two CVS-related visual problems

The present study examined whether children and adolescents can correctly report dry eyes and blurred distance vision, two visual problems associated with computer vision syndrome. Participants are 913 children and adolescents aged 6–17. They were asked to report their visual problems, including dry eyes and blurred distance vision, and received an eye examination, including tear film break-up time (TFBUT) and visual acuity (VA). Inconsistency was found between participants' reports of dry eyes and TFBUT results among all 913 participants as well as for all of four subgroups. In contrast, consistency was found between participants' reports of blurred distance vision and VA results among 873 participants who had never worn glasses as well as for the four subgroups. It was concluded that children and adolescents are unable to report dry eyes correctly; however, they are able to report blurred distance vision correctly. Three practical implications of the findings were discussed.

Practioner Summary: Little is known about children's ability to report their visual problems, an issue critical to diagnosis and treatment of children's computer vision syndrome. This study compared children's self-reports and clinic examination results and found children can correctly report blurred distance vision but not dry eyes.