综合地形环境建模与数据库实现

该文分析了现代军事仿真系统对地形环境数据的需求，采用面向对象方法构建了地形环境数据模型，根据地形环境数据模型设计了基于有向无环图结构的综合地形环境数据库，将各种仿真子系统所需的地形环境数据集成在一起，有效地解决了不同仿真应用中地形环境数据的一致性、相关性和多分辨率的问题；通过将综合地形环境数据库映射到SEDRIS表示，促进了地形环境数据的重用和共享；该文还介绍了综合地形环境数据库的数据源，分析了地形环境数据库的生成流程，最后提出了一种OpenFlight格式地形环境数据库的实现方法，节约了数据库的开发成本。     

一种大规模地形的快速漫游算法

地形漫游在仿真、模拟、虚拟现实等领域中有着广泛应用。大规模地形的实时漫游算法一般采用视见体裁剪和与视点相关的连续细节层次等技术来减少实际绘制的地形数据量。通过地形分块和视见体投影三角形扫描算法实现快速裁剪，通过调整顶点的高度值消除裂缝，通过基于三角形的四叉分割实现连续细节层闪地表简化，简化了算法实现，提高了算法效率，在没有利用帧连贯性的情况下，算法可以在PC机上实现较大规模地形的快速交互式漫游。     

遥感提取叶面积指数的地形影响分析

结合1：50000DEM对贵州省黎平县内研究区的ETM 遥感影像进行地形纠正，分别使用地形纠正前后的图像建立植被指数与实测杉木林、阔叶林、竹林的叶面积指数相关关系，从而对研究区森林叶面积指数进行计算。研究表明，利用遥感影像计算山地丘陵林区叶面积指数时地形是一个重要的影响因素，它致使遥感影像提取的叶面积指数出现一定的偏差。因此．本文从电磁波辐射传输理论着手，采用一种地形影响去除方法，即先把遥感图像归一化为没有地形影响下的亮度图像，再通过该亮度图像提取森林叶面积指数，并通过实地观测数据验证了该地形纠正方法的有效性。同时，也提出了利用地形因子和遥感影像亮度值的关系计算大气程辐射的方法。     

一般型最优有限预见控制及其在地形跟踪中的应用研究

提出一种新的预见控制方法－－一般最优有限预见控制方法，并将其应用于巡航导弹地形跟踪控制设计。将参考信号和干扰信号考虑成更一般的形式，在其自相关函数数值已知的条件下，得到了一般型有限预见伺服系统设计问题的最优解。通过仿真证实，采用该方法设计地形跟踪系统，可以明显地改善巡航导弹的地形跟踪性能。     

基于LOD的三维作战地形实时渲染技术的研究

与视点相关的三维作战地形实时渲染技术一直是作战仿真领域的热点问题之一。三维作战地形渲染的主要问题是如何缩减三角形的数目问题。该文采用了一种基于四叉树的LOD算法，根据与视点以及和地形本身起伏程度相关的技术来决定地形应有的细节程度，然后递归的分割四叉树的每一个节点，直到到达需要的细节程度，从而较好地解决了实时渲染过程中的三角形数目问题。通过仿真试验，在保证渲染速度的前提条什下，该方法有效地实现了作战仿真系统中实时地形的漫游和不同视场的条件下的地形细节显示。并且具有较高的视觉真实程度。     

利用小波进行多尺度地形生成方法的研究

针对随机中点位移法难以生成符合ｆＢｍ特征的三维地形之缺点，本文把地形看成层次性随机统计过程，提出了利用小波进行多尺度地形生成的新方法，首先利用扩展的随机－相关法按给定的地形参数（均值、地形高程标准差、地形相关长度、地形粗糙度等）形成一定数量用来表示地形骨架的地形特征点，然后与通过小波机制产生的多尺度地形局部细节信号相综合，通过小波多尺度合成获得符合要求的具有任意细节水平的“真实”的三维地形。试验证明这一方法切实可行，可作为随机中点位移法的改进     

适应地形实时生成的地形数据简化

出于对大范围地形场景实时生成的需要，提出了一种地形数据简化的方法。首先基于“分而治之”思想给出规则数据分割的概念，并给出数据分割算法，然后通过将地形数据的高度值解释为二维图像元素的灰度值，把地形数据变成平面图像，再利用数字图像处理的方法获得地形特征，提出了两种地形分类简化模型，即基于熵的地形类型划分模型和基于DEM数据统计特性的地形类型划分模型，最后比较了不同地形特征的数据简化结果。     

虚拟城市构建中地形数据的互操作研究与实现

地形数据是虚拟城市构建过程当中必需的三种最重要的数据之一，由于虚拟城市构建中采用的方案各异，使用的软件和硬件平台也不尽相同，因而各方案能够接受的地形数据格式也存在很大的差异，因此在不同软件、硬件平台下不同格式的地形数据之间共享对于虚拟城市的快速构建起着至为重要的作用。该文以五种国内外最常见的地形数据作为本次研究的对象，并从地形数据共享出发，在摒弃传统的数据转换共享模式情况下，采用基于公共标准的地形数据互操作共享模式来进行地形数据的共享研究，最后并对其进行了实现。     

基于人工神经网络的地形线性化方法

地形线性化方法对地形辅助导航系统性能有重要的影响。本文采用人工神经网络这一新技术来分块记忆地形数据，给出数字地图上任意位置的线性化参数，并用于系统状态的扩展卡尔曼滤波，与其他传统地形线性化方法相比，用人工神经网络来处理地形函数，系统滤波性能得到改善，提高了导航精主工，并可减少地图的存贮量，适用并行处理。     

一种基于TIN的大规模地形实时可视化算法研究

在地形可视化领域中,如何对大规模地形的数据进行处理和可视化一直是一个关键问题.本文提出一种有效的实现方法.采用平均分割方法对大规模地形数据进行分割.其中重点解决地形块简化时相邻地形块问的边界处理问题;通过基于半边收缩和顶点分裂操作获得多分辨率TIN模型,并改进顶点分裂操作方法.实验结果表明,采用本方法可以实时生成大规模地形,提高了地形漫游的效率与可视化效果.     

遗传规划算法在化合物设计、筛选研究中的应用

采用计算机科学中新兴的遗传规划算法思想，结合化学物质的本质特点，运用进化操作来实现化合物的合成设计和筛选。文中针对算法运用讨论了函数集、终止集问题，通过计算元素组成的字符串的化合价的结果来确定适应度函数，既符合化学学科的本质规律，又满足了算法的要求。通过复制、交换和突变操作，经过多代次的进化终止，取得了满意的结果。文章还针对其实用性，从化学本质出发，提出了建议和研究方向。可以说本文是遗传规划在化学化合物合成筛选中运用的成功探索，同时也为进一步研究打下了坚实的基础。     

Promotion and prevention orientations in the choice to attend lectures or watch them online

When presented with the option to use a new instructional technology, students often face an approach–avoidance conflict. This study explored promotion and prevention orientations, concepts linked to approach and avoidance in Higgins's regulatory focus theory, in the choice to attend lectures or watch them online. Openness, a core disposition in the Big Five Model of personality, and positive attitudes towards the utility of the Internet, reflect promotion orientations that are potentially related to the choice to watch lectures online. By contrast, neuroticism, another core disposition in the Big Five Model, and anxiety about the Internet as a computer technology, reflect a prevention orientation that is potentially related to the choice of attending lectures in class. The results illustrate that both promotion and prevention are at work in the choice to attend lectures or to watch them online. Neuroticism and anxiety about the Internet as a computer technology were related to the choice to attend lectures in class, whereas the perceived utility of the Internet was related to the choice to watch lectures online. Instructional mode choice was not related to examination performance, suggesting that the choice to attend lectures or watch them online has more to do with individual differences in promotion and prevention orientations than with pedagogical characteristics that impact learning.     

海量大气颗粒物成分分析系统

2011年以来, 我国多地出现了雾霾天气, 对大气颗粒成分分析有助于人们了解雾霾形成的原因, 制订有效的应对措施. 本文的主要目的是对于大气颗粒物成分进行命名. 传统颗粒物的命名是在经验的基础上, 对颗粒进行逐个的命名. 若将该过程自动化, 难点有两个: 数据规模太大、人工经验难以量化. 本文使用数据挖掘的工具, 首先进行了一次聚类分析, 降低了数据规模. 为了解决人工经验难以量化的问题, 使用逻辑回归分类算法, 并进行了调优, 使正确率达到了业务处理的要求.     

From remote maintenance to MAS-based e-maintenance of an industrial process

One of the main consequences of the extended enterprise is the emergence of new forms of relationships between the customer and the supplier in order to ensure the quality of service of the object throughout the life cycle. Innovative communication and co-operation methods are needed to support these new relationships. The combination of modern information processing and communication tools, commonly referred to as tele-service, offers the technical support required to access remote information. Indeed, it is easier to transfer information and knowledge to different actors than to move an actor to the site. However, even if this technical support is necessary for information communication, it is insufficient to develop a co-operation-based working situation that involves many self-motivated customers and suppliers sharing a common goal. This synergy is an emergent property of the system as a whole, and it is not expected to be obtained as a simple sum of its components. For example, a challenging problem in the field of product manufacturing is to assist the operator in its decision-making, when the system functioning is degraded, to preserve the system under service at maximum (anticipation of the failure) while remaining it in a space of allowed operation (to avoid consequences of an error in judgement). That means an evolution from tele-service to e-work and e-maintenance in particular where the assistance to operator results from collaboration of maintenance processes and experts. Consequently, this paper examines some issues and challenges involved in the evolution from the tele-maintenance of an industrial platform to the e-maintenance, and then proposes a multi-agent system-based collaboration as a solution to implement the e-maintenance experiments.     

Affinity-Based Network Interfaces for Efficient Communication on Multicore Architectures

Improving the network interface performance is needed by the demand of applications with high communication requirements (for example, some multimedia, real-time, and high-performance computing applications), and the availability of network links providing multiple gigabits per second bandwidths that could require many processor cycles for communication tasks. Multicore architectures, the current trend in the microprocessor development to cope with the difficulties to further increase clock frequencies and microarchitecture efficiencies, provide new opportunities to exploit the parallelism available in the nodes for designing efficient communication architectures. Nevertheless, although present OS network stacks include multiple threads that make it possible to execute network tasks concurrently in the kernel, the implementations of packet-based or connection-based parallelism are not trivial as they have to take into account issues related with the cost of synchronization in the access to shared resources and the efficient use of caches. Therefore, a common trend in many recent researches on this topic is to assign network interrupts and the corresponding protocol and network application processing to the same core, as with this affinity scheduling it would be possible to reduce the contention for shared resources and the cache misses. In this paper we propose and analyze several configurations to distribute the network interface among the different cores available in the server. These alternatives have been devised according to the affinity of the corresponding communication tasks with the location (proximity to the memories where the different data structures are stored) and characteristics of the processing core. As this approach uses several cores to accelerate the communication path of a given connection, it can be seen as complementary to those that consider several cores to simultaneously process packets belonging to either the same or different connections. Message passing interface (MPI) workloads and dynamic web servers have been considered as applications to evaluate and compare the communication performance of these alternatives. In our experiments, performed by full-system simulation, improvements of up to 35% in the throughput and up to 23% in the latency have been observed in MPI workloads, and up to 100% in the throughput, up to 500% in the response time, and up to 82% in the requests attended per second have been measured in dynamic web servers.     

IPv6协议下域名系统的扩展与实现

为了实现对IPv6协议的支持，需要对现有IPv4协议下的域名系统进行相应的扩展，以使其能在IPv6协议下正确地进行IP地址与域名的正向或反向解析。域名系统的扩展主要包括以下两方面：一是增加了两个新的资源记录AAAA和A6来存储IPv6地址，以实现域名到IPv6地址的正向解析；二是增加了两个新域：ip6.int和ip6．arpa，以实现IPv6地址到域名的反向解析。文中以著名的域名系统软件BIND为对象，以Linux操作系统Redhat9作为实验平台，详细介绍了基于Linux平台的域名系统对IPv6协议的扩展与实现，从而为实现IPv4到IPv6的平稳过渡打下了坚实基础。     

探析计算机硬件故障分析与维护

随着科学技术不断发展与进步,计算机硬件所需要的技术要求越来越高,因此,我们应该对其出现的故障进行及时分析,并且还要在分析的基础上提高维护水平。从现有的计算机来看,类型比较多样,有笔记本、商务本、超极本、电脑主机一体机等等,不同的计算机需要采用不同的维护方式,否则很容易导致故障频发。另一方面,我们要对计算机硬件故障进行详细的分析,找出故障的根源,一举解决问题,否则很有可能会让计算机遭到更大的损坏。计算机硬件故障分析与维护是一整套连贯性的检修工作,需要互相配合才能取得更好的结果。     

广告设计之互动创意

在激烈的市场竞争中,无论是国际还是国内的企业,都把提高广告设计水平作为提升竞争力的一种手段,广告设计创新显得越来越迫切。本文试图从互动角度来探讨广告设计创意,目的有两个:一个是拓宽广告设计理论的研究空间,预测互动创意作为一种广告设计创新途径的未来发展和可能;第二个目的是为广告设计实践总结和归纳新的思考和创作方法,以拓宽设计实践者的创意思维空间,丰富表现语言。本文通过研究国内外最新的广告设计成功案例,探讨了广告设计之互动创意的途径和方法,期望能对相关设计领域的研究和实践提供参考价值。     

The reality of medical work: The case for a new perspective on telemedicine

This paper considers the nature of medical work and how new telemedicine technologies can be developed to support that work. Telemedicine developers attempt to increase communication and collaboration between medical practitioners and between patients and medics, with the goal being to make medical care and information more easily accessible. However, the focus of telemedicine systems appears to have so far been technology centred, and the work they are trying to support is often ignored. We argue that to develop appropriate telemedicine technologies, it is important to understand the nature of medical work, and to examine the manner in which medical practiceactually occurs. Only then will we be in a position to design appropriate telemedicine technologies to support these activities. Unless designers have an insight into the work itself, new technologies will continue to fail to support what telemedicine effectively aims to promote — collaboration and access to distributed knowledge.     

The electrical distribution network planning problem

In this paper we are dealing with the electrical distribution network planning problem where a network configuration has to be specified in order to meet demand, to satisfy the operating constraints, and to minimize investment, operating, and power–loss costs. The iterative procedure includes several heuristic algorithms to generate a radial network, to choose a set of open feeders to meet the reliability constraint, and to solve the reconfiguration problem in order to reduce the power–loss costs. Furthermore, in order to compare the reliability of potential solutions, a predictive reliability assessment measure is established.