MVC在Web系统中的模式与应用

面向对象的设计模式是经验的总结，MVC思想是原先用于构建用户界面的。这篇文章主要论述了如何在新的Web应用领域中使用设计模式和MVC架构。文章首先介绍了设计模式的概念和特点，以及MVC架构的设计思想，并分析了MVC架构中包含的几种主要的模式。然后根据Web应用系统的特点，就如何应用模式和MVC架构提出了一些设计思路。     

MVC设计模式在JSP开发中的应用

针对目前多层Web应用开发的难点,讨论了MVC设计模式,并将MVC设计模式引入JSP应用开发中.MVC设计模式分离了数据的控制和数据的表现,在实现多层Web应用系统中具有明显的优势.     

基于Struts体系结构的Web应用

简要地介绍了Web应用中的MVC设计模式以及当前流行的Struts体系结构，结合实例介绍了Struts的实现方法。体．现了MVC设计模式在Web应用中的高效率与可扩展性。     

基于MVC设计模式的Web服务架构

Web服务以其良好的协同性和可扩展性，越来越受到企业的关注，但如何构建企业的Web服务是一个非常复杂的问题。MVC是一种架构松散耦合、高柔韧性软件的设计模式，它为架构Web服务提供一种很好的模型。本文描述了MVC设计模式，通过它和Web服务架构相关要素的类比，用MVC的设计模式描述了Web服务的体系结构，建立了基于MVC模式的Web服务架构。     

Struts——基于MVC模式的Web开发框架

介绍了在大型Web应用开发中常使用的MVC设计模式和基于MVC模式的Web开发框架——Struts框架。首先对MVC模式做了详细介绍，指出其优点，并对Struts框架的工作原理和各个组件的构成进行了介绍，使读者对MVC设计模式和Struts框架有了一个清楚的了解。     

基于Struts和动态表单的MVC设计模式

文章介绍了MVC设计模式，分析了基于MVC模式发展出的Struts Web应用框架以及动态表单技术的工作原理。提出将这两者结合起来实现MVC设计模式的思想，给出了临床诊断信息系统的应用实例。     

Web应用系统设计与实现的原理

本文详细介绍了MVC作为开发Web应用的架构,MVC设计模式三个组成构件（模型部件、视图部件和控制部件）实现原理,MVC设计模式的扩展,以及在ASP．NET环境下实现基于MVC的应用需要完成的工作,讨论了MVC模式的优势。     

基于MVC模式的Web框架设计关键技术研究

基于B/S架构的网络应用,越来越受到人们的重视,因此MVC设计模式被广泛用于Web应用开发。人们提出了许多基于MVC设计模式的Web框架,以便节省软件开发的时间。通过研究Struts 2.0框架实现MVC的机制,总结基于MVC模式设计Web框架时需要的各种关键技术,以方便快速实现自己的Web框架。     

Web应用系统设计与实现的原理

本文详细介绍了MVC作为开发Web应用的架构,MVC设计模式三个组成构件(模型部件、视图部件和控制部件)实现原理,MVC设计模式的扩展,以及在ASP.NET环境下实现基于MVC的应用需要完成的工作,讨论了MVC模式的优势。     

基于Java Web的Struts框架的应用

结合实例给出了MVC 设计模式在J2EE Web层的一种有效的应用,并运用开源的Struts框架实现了MVC设计模式,还对MVC模式与Struts框架的内部实现机制进行了分析,并在实践中体现出MVC设计模式与Struts框架的高效和结构清晰的优点.     

Remote sensing of soil salinity: potentials and constraints

Soil salinity caused by natural or human-induced processes is a major environmental hazard. The global extent of primary salt-affected soils is about 955 M ha, while secondary salinization affects some 77 M ha, with 58% of these in irrigated areas. Nearly 20% of all irrigated land is salt-affected, and this proportion tends to increase in spite of considerable efforts dedicated to land reclamation. This requires careful monitoring of the soil salinity status and variation to curb degradation trends, and secure sustainable land use and management. Multitemporal optical and microwave remote sensing can significantly contribute to detecting temporal changes of salt-related surface features. Airborne geophysics and ground-based electromagnetic induction meters, combined with ground data, have shown potential for mapping depth of salinity occurrence. This paper reviews various sensors (e.g. aerial photographs, satellite- and airborne multispectral sensors, microwave sensors, video imagery, airborne geophysics, hyperspectral sensors, and electromagnetic induction meters) and approaches used for remote identification and mapping of salt-affected areas. Constraints on the use of remote sensing data for mapping salt-affected areas are shown related to the spectral behaviour of salt types, spatial distribution of salts on the terrain surface, temporal changes on salinity, interference of vegetation, and spectral confusions with other terrain surfaces.As raw remote sensing data need substantial transformation for proper feature recognition and mapping, techniques such as spectral unmixing, maximum likelihood classification, fuzzy classification, band ratioing, principal components analysis, and correlation equations are discussed. Lastly, the paper presents modelling of temporal and spatial changes of salinity using combined approaches that incorporate different data fusion and data integration techniques.     

Integration | Innovation | Inclusion: Values,Variables and the Design of Human Environments

Complexity, complication, contradiction, consumption, confusion, delusion, depression. Opportunity, inspiration, ingenuity, compassion, wisdom. Our world is perplexing, our times are fast moving, and our choices are many. To find an appropriate path is a daunting yet vital challenge that confronts us as individuals, as communities, and as a civilization. How sustainable is our world? How reasonable are our behaviors? The present article is a collection of thoughts on a series of intertwined issues related to the contemporary world, its environmental dimensions, and their present-day problems. The goal is to survey the landscape through a lens of Environmental Design, to provide some perspectives, to raise some questions, and to explore systems, beliefs, and values informing and influencing actions. It is important to consider how people's belief systems influence, inform, and shape actions. This holds true in realms political, spiritual, and cultural. It also proves relevant in the ways in which we imagine, design, develop, and construct our buildings, cities, spaces, and places.

Appropriate solutions to some of our most daunting problems will arise through the concerted efforts, open dialogue, and collective wisdom of the wide array of stakeholders, professionals, politicians, decision makers, and citizens (both engaged and disenfranchised) who have the will and wherewithal to make a difference and to make the world safer, healthier, and better. It seems vital for us to critically examine, and question, our belief systems and their connections to the ways we define, refine, and realize progress. Architecture and Environmental Design, in both a philosophical and a practical sense, reflect as well as form greater aspirations, directions, and events of our times.     

区块链+物联网在农产品溯源中的应用研究

近年来,农产品安全问题日益严峻,传统的农产品追溯体系面临公信力缺失、监管困境和扩展性问题,农产品质量安全追溯迫在眉睫。随着区块链技术不断发展,其具有的分布式、去中心化、不可篡改、可追溯等特性在改善农产品溯源系统数据安全性、透明性等方面发挥着重要作用,并受到了各个行业的广泛关注。在简述可追溯性和追溯系统概念的基础上,介绍物联网和区块链技术,并探讨了当前国内外学者将区块链和物联网框架融合应用到农产品溯源中的一些相关研究,同时阐述了溯源系统在物联网与区块链结合下带来的安全、可靠、透明等好处及面临可扩展性、效率问题、资源浪费等挑战,最后对当前农产品溯源体系建设提出建议以及未来的研究方向。     

面向大尺寸货物运送的吊车控制方法综述

随着现代化工业和基础设施建设的飞速发展,面向大尺寸货物运送的吊车系统以其高负载能力、低成本的显著优势广泛应用于集装箱搬运、风机安装、飞机机翼机身移动、水轮发电机转子安装、海上钻井平台搭建等诸多重要领域。然而,相对于传统的点质量单摆吊车系统,面向大尺寸货物运送的吊车系统具有更高的欠驱动程度、更强的状态耦合性和更加复杂的非线性,给大尺寸货物高效、安全的运送控制带来严峻挑战。本文首先简单阐述了面向大尺寸货物运送吊车系统不同吊装形式的建模、优势和缺点;然后,详细介绍了点质量双摆吊车系统、分布式质量双摆吊车系统和多吊车协同运送系统控制的研究现状;最后,对面向大尺寸货物运送吊车系统控制的研究现状进行概括,并对可能存在的关键问题和未来的研究方向进行了讨论和展望。     

Expert system verification and validation: a survey and tutorial

Assuring the quality of an expert system is critical. A poor quality system may make costly errors resulting in considerable damage to the user or owner of the system, such as financial loss or human suffering. Hence verification and validation, methods and techniques aimed at ensuring quality, are fundamentally important. This paper surveys the issues, methods and techniques for verifying and validating expert systems. Approaches to defining the quality of a system are discussed, drawing upon work in both computing and the model building disciplines, which leads to definitions of verification and validation and the associated concepts of credibility, assessment and evaluation. An approach to verification based upon the detection of anomalies is presented, and related to the concepts of consistency, completeness, correctness and redundancy. Automated tools for expert system verification are reviewed. Considerable attention is then given to the issues in structuring the validation process, particularly the establishment of the criteria by which the system is judged, the need to maintain objectivity, and the concept of reliability. This is followed by a review of validation methods for validating both the components of a system and the system as a whole, and includes examples of some useful statistical methods. Management of the verification and validation process is then considered, and it is seen that the location of methods for verification and validation in the development life-cycle is of prime importance.     

区块链分片技术综述

区块链作为分布式账本的关键技术之一,其去中心化、可匿名、不可篡改的特性受到学术界和工业界的青睐,被广泛应用于金融、数字货币、公共服务等领域。分片技术作为区块链扩容的主流方式之一,能够在不降低区块链去中心化程度的同时实现高性能的链上扩容,从而解决区块链可拓展性不足以及吞吐量较低的问题。介绍近年来出现的分片技术以及相关协议,总结分片技术的关键理论与方法,从分片配置、重配置、片内共识协议、跨片共识协议、状态存储等方面对分片技术方案进行对比,归纳不同分片方案在网络分片、交易分片、状态分片等设计中存在的优势和不足。同时,阐述一些经典分片技术在性能和实现方式上的特点,对许可区块链和无许可区块链、片内共识协议、跨片共识协议、准入性方案、状态分片方式等进行分析和概述。在此基础上,从分片内、分片间以及系统层级的角度总结分片技术当前所面临的困境和挑战,并对该领域的发展前景及未来研究方向加以展望。     

Survival analysis of a neotropical rainforest using multitemporal satellite imagery

We present results of an analysis of deforestation at a UNESCO Biosphere Reserve, the Parque National Yasuní, located in the rainforests of eastern Ecuador using multitemporal Landsat TM and ETM+ satellite imagery. Using survival analysis, we assessed both current and future trends in deforestation rates, and investigated the impact of spatial, cultural, and economic factors on deforestation. These factors included the distance from roads, rivers, research facilities, oil facilities, markets and towns, and land ownership by colonists, native inhabitants, and an oil company. We found the annual rate of deforestation is currently only 0.11%, but that this rate is increasing with time and, assuming that the trend of increasing rate of forest loss continues, we would predict that by 2063, 50% of the forest within 2 km of an oil access road will be lost to unhindered colonization and anthropogenic conversion. The Quechua colonists are associated with areas of the highest rate of deforestation, followed by the native Huaorani and the lowest region of deforestation was in areas occupied by a local oil company. By far, the strongest predictor of where deforestation is predicted to occur was proximity to the road. Proximity to research sites, oil facilities, market, and rivers significantly decreases deforestation rates, and proximity to towns significantly increases deforestation rates.     

联邦开发过程中的校核、验证与确认（VV＆A）

对联邦的VV＆A不仅能够使每一步的工作得到跟踪和衡量,还使每一步能够减少多余的工作量,巩固需要加强的工作,明确开发人员的角色和职责,从而使人力、时间、资金等资源得到更加有效率的利用,仿真的结果变得更加可预测和准确,在很大程度上减少了编程的风险.联邦成员描述了仿真模型的各对象类、交互类、相关的属性、参数等信息,而联邦是各联邦成员的有机集成,构成具有特定功能的仿真系统.因此,联邦成员的正确性是联邦正确性的前提,决定了仿真系统的成败.在VV＆A的过程中,最好采用一些自动化工具以便于工作,同时要根据具体仿真系统的实际情况来确定VV＆A所需要作的工作.     

On Belief and the Making of All Things Beautiful and Sublime: Creation by Ordinance and Destruction by Chaos

This is a study of beauty as a construct and a property of structural composition. I examine alternate possibilities of structural compositions, linguistics, or material arguments that beauty, impossible in utter chaos, might not be definitely found in order, but the latter is essential thereto. A distinction is also made between complex systems of order found in nature, often qualified as organic—the seemingly free and flowing forms found in formal sophistication beyond simple geometrical reduction—and the absence of order as pure chaos. Beauty is examined through order from historical linguistic, perceptual, and systemic constructivist perspectives, along with the sublime and the harmonious. Linguistically, order is a term of convergence of the seemingly disparate streams of significance of rank—in society, religion, and the belief in collective constants—and ornament is a term of bearing beauty and enhancement of taste that emanates from within the structure and should not be reduced to superficial application. I cite costume, including accessories of weaponry, as moments of proximity between style, purpose, utility, and the collective as semiotic bearer of meaning in culture and social order.     

一种基于对象信息的MIS自适应生成器

为解决MIS在开发和运行过程中因需求频繁变更所带来的开发和维护的工作量上升问题,提出一种新的MIS软件基础模块自适应生成管理器。通过信息化管理MIS的版本、用户与权限、系统结构、系统模块、对象信息、通用视图元素、通用业务逻辑元素和通用数据访问方式,并基于通用的界面层基础元素、业务逻辑层基础元素、数据访问层基础元素和对象信息自适应生成或重构MIS软件基础模块的数据库、交互界面、业务逻辑、数据交互部分和软件内部结构,以达到动态构建和管理MIS软件基础模块,实现基础模块信息化和系统对自身信息化、自动化管理的目的。通过将该生成器技术实现并实际应用于MIS开发,验证其能够较好地应对MIS基础模块的快捷构建与变更,有效降低MIS开发与维护的工作量。该生成器较好地解决了MIS软件基础模块快速构建与重构问题,能较好地应对MIS在开发和运行过程中的频繁变更。