Using local transition probability models in Markov random fields for forest change detection

Change detection based on the comparison of independently classified images (i.e. post-classification comparison) is well-known to be negatively affected by classification errors of individual maps. Incorporating spatial-temporal contextual information in the classification helps to reduce the classification errors, thus improving change detection results. In this paper, spatial-temporal Markov Random Fields (MRF) models were used to integrate spatial-temporal information with spectral information for multi-temporal classification in an attempt to mitigate the impacts of classification errors on change detection. One important component in spatial-temporal MRF models is the specification of transition probabilities. Traditionally, a global transition probability model is used that assumes spatial stationarity of transition probabilities across an image scene, which may be invalid if areas have varying transition probabilities. By relaxing the stationarity assumption, we developed two local transition probability models to make the transition model locally adaptive to spatially varying transition probabilities. The first model called locally adjusted global transition model adapts to the local variation by multiplying a pixel-wise probability of change with the global transition model. The second model called pixel-wise transition model was developed as a fully local model based on the estimation of the pixel-wise joint probabilities. When applied to the forest change detection in Paraguay, the two local models showed significant improvements in the accuracy of identifying the change from forest to non-forest compared with traditional models. This indicates that the local transition probability models can present temporal information more accurately in change detection algorithms based on spatial-temporal classification of multi-temporal images. The comparison between the two local transition models showed that the fully local model better captured the spatial heterogeneity of the transition probabilities and achieved more stable and consistent results over different regions of a large image scene.     

服务接触中的不公平事件：从顾客的角度

This study was designed to answer several key questions regarding the service injustice customers perceived during the service delivery. Using the critical incident technique, the authors collected 195 unfair incidents from a variety of service organizations. The initial sorting of the incidents resulted in four major groups: information asymmetry, unfair procedure, inappropriate attitudes and manners of the service personnel, and unfair outcomes. Within the four major classifications of critical incidents, 13 secondary categories were identified. A further analysis was conducted to discover the underlying reason why customers feel unfair in the service encounters. Finally, some implications for service managers were discussed.     

在ASP.NET 2.0中自动化构建数据访问层

使用ASP.NET2.0所提供的BuildProvider类,将自动化构建的数据访问层源代码编译到程序集中,使得开发者利用Ob-jectDataSource控件,可以简单、快速地实现三层架构的Web应用。     

远程作业技术中公式编辑问题的解决方案

随着远程教育的不断发展,远程作业技术的研究与开发被提到越来越重要的位置。对于理工科专业的基础课来讲,学生在作业中需要输入大量的数学表达式,这些数学表达式最终必须由计算机自动进行识别和批改。针对这种情况,提出了适合于计算机自动识别的数据结构以及特殊结构的数据逻辑关系等,在此基础上对作业系统中的公式编辑器进行了设计和开发。     

基于FSVM光伏系统最大功率跟踪算法及仿真研究

针对光伏组件中常用的最大功率跟踪方法存在的不足,提出并建立了模糊支持向量机(FSVM)的最大功率点工作电压预测模型.通过对实测气象光强数据进行的仿真分析表明,与BP神经网络模型相比,FSVM的模型实现了结构风险最小化原则,对未来的样本有较好的泛化能力,具有更高的预测精度和稳定性.     

基于动态口令认证的VPN研究与设计

本文基于动态口令认证,构建一个部署代价不高,既能够安全认证,又能够安全传输的VPN系统。在当前最流行的I-Psec框架基础上,进行了一定的简化和修改,实现了一个IPsec体系的、具有基本VPN功能的原型系统。     

用VB标签控件实现动态效果

在VB程序设计里．标签通常是作为在窗口里显示文字信息的。用活标签的常用属性。并合理使用计时器控件。就能够呈现出动态的文字效果。为窗口界面增添活力。     

An efficient multiobjective differential evolution algorithm for engineering design

Solving engineering design and resources optimization via multiobjective evolutionary algorithms (MOEAs) has attracted much attention in the last few years. In this paper, an efficient multiobjective differential evolution algorithm is presented for engineering design. Our proposed approach adopts the orthogonal design method with quantization technique to generate the initial archive and evolutionary population. An archive (or secondary population) is employed to keep the nondominated solutions found and it is updated by a new relaxed form of Pareto dominance, called Pareto-adaptive ϵ-dominance (paϵ-dominance), at each generation. In addition, in order to guarantee to be the best performance produced, we propose a new hybrid selection mechanism to allow the archive solutions to take part in the generating process. To handle the constraints, a new constraint-handling method is employed, which does not need any parameters to be tuned for constraint handling. The proposed approach is tested on seven benchmark constrained problems to illustrate the capabilities of the algorithm in handling mathematically complex problems. Furthermore, four well-studied engineering design optimization problems are solved to illustrate the efficiency and applicability of the algorithm for multiobjective design optimization. Compared with Nondominated Sorting Genetic Algorithm II, one of the best MOEAs available at present, the results demonstrate that our approach is found to be statistically competitive. Moreover, the proposed approach is very efficient and is capable of yielding a wide spread of solutions with good coverage and convergence to true Pareto-optimal fronts.     

解析惠安女服装的结构美——小柞节约衫、阔腿裤的款式结构和原型制定

本文从服装款式和结构原型的角度对小柞地区的惠安女服装的节约衫和阔腿裤的进行分析,对惠安女服装本身的研究大多是以服装的款式、色彩、纹样等服饰元素为研究对象,但对惠安女服饰结构的研究尚属空白,本文从服装设计学的角度对其最本质的款式和结构进行分析,以期对未来惠安女服饰美学的研究有所帮助,为现代服装设计提供设计素材;同时,为惠安女服装制作基本原型也是民俗服饰学研究手法新的尝试。     

基于Struts的Web开发

Struts是目前比较流行的一个基于MVC设计模式的JavaWeb应用框架,文章详细地阐述了Struts框架实现MVC的构架机制及其核心组件和框架特点,介绍了集成在Struts框架内部的Validator框架在具体Web系统中的开发应用,比较了基于该验证框架的两种验证的优缺点。