情景交融人岛共生——黄官岛数字海岛概念设计方案

文中介绍了福建省福清市黄官岛的数字海岛概念设计,针对\"未来数字海岛\"的发展概念,从不同使用情景出发,提出\"多情景规划\"设计概念,重在体现未来黄官岛的智能化与数字化如何与规划设计结合,对数据支持下的智慧海岛设计进行了有益的探索。国家自然科学基金面上项目(41671141);;\n福建省自然科学基金项目(2015J01226);;\n中央高校基金项目(20720170046);;\n厦门市科技局项目(3502Z20183005);;\n厦门大学大学生创新创业训练计划项目(2018X0282

基于函数式方法的CGI程序设计

由于HTTP 天生的无状态性质，Web 程序设计中产生了这样一个问题：在两个连续的用户交互之间会遗忘状态信息。一个交互性的 Web 应用程序由一组脚本构成，每个交互都包含两个脚本，一个脚本向浏览器递交页面（然后结束），用户及时完成并提交表单，然后另一个（可能是不同的）脚本处理提交的表单。所以，应用程序逻辑分布在多个脚本之间。 由于浏览器还允许用户在交互中回溯，或者克隆一个正在处理中的交互过程，之后并行执行这两个交互过程，所以问题变得更加复杂。Web 开发框架（例如 Spring 和 Struts）允许处理多个交互，但是它们进一步提高了整体上已经很复杂的代码库的复杂性。 在本文中，我们将几种函数式方法应用到Web程序设计中，从而简化复杂 Web 应用程序的开发。我将从介绍 continuation 的应用开始，逐步引入CPS，Trampoline，Lambda Lifting等函数式方法，通过用Scheme语言编写的一个CGI实例详细展示函数式方法的效果，并进一步将这些方法在C语言中实现。Due to the inherent stateless nature of HTTP, Web technologies suffer from the problem of state information being forgotten between two successive user interactions. An interactive Web application consists of a collection of scripts wherein a single interaction comprises one script delivering a page to the browser (then ending), the user completing and submitting the form at some later point in time, and another (possibly different) script handling the submitted form. Thus, application logic is spread across a multitude of scripts. Matters are further complicated by the fact that browsers allow users to backtrack in their interactions or clone an in-progress interaction and run both in parallel. Web development frameworks, such as Spring and Struts, allow programmers to handle multiple navigational paths, but they cost of increasing the complexity of code base. In this thesis, we introduce several functional methods into Web programming, in order to simplify the complexity of Web development. We’ll start from the application of continuation, and then utilize CPS, trampoline and lambda lifting step by step. A instance of CGI script programmed in Scheme will be shown later, to display how these methods work, and will be further implemented in the language C

Research on Observer Sitting Problem in Terrain Visiblilty Analysis

观察点设置问题是地形可视性分析中的一类重要问题，对该问题的研究可以在空间信息辅助决策、通信、旅游、野生动物保护等领域发挥重大作用。本文在对地形可视性分析中观察点设置问题现有研究成果总结和分析基础上对该问题展开深入研究。 首先，针对现有解决方法只从智能算法或地形数据表示方法单一角度进行分析和研究的局限性，提出了一种问题相关的智能算法和数据表示方法相结合的解决问题新框架。该框架考虑了解决观察点设置问题时智能算法的优点和数据表示方式的特点相互配合问题，目的是充分发挥二者各自的优势以提高观察点设置问题解决的准确度与效率。 其次，在深入分析观察点设置问题本身特点的基础上，结合隶属云理论的基本理论和方法，对经典模拟退火算法从退温函数设计、温度产生过程、状态生成过程三方面进行了问题相关的改进，提出了一种适于观察点设置问题的改进模拟退火算法(Improved Simulated Annealing algorithm, ISA)。该算法一方面保持了经典模拟退火算法的稳定倾向特性，保证了算法满足伴随退火温度的不断下降，对恶化的新状态越来越难于接受这一模拟退火算法的最基本特征；另一方面其退火温度的连续性随机变化特性和隐含的“回火升温”过程，则有利于算法有效拒绝恶化解，加速算法收敛，能够更好地满足观察点设置问题对于算法收敛速度的要求。 再次，在分析地形数据的精度、误差等因素对观察点设置问题的解决准确性和解决效率影响程度的基础上，提出了一种基于离散余弦变换的地形数据内插方法(Discrete Cosine Transformation Interpolation method, DCTI)。新方法将传统空域上的地形内插转换到变换域上进行，同时充分利用了离散余弦变换的熵保持特性和能量压缩特性，简化了变换域上的内插过程，提高了地形数据内插的效率和精度。DCTI方法与其他现有典型地形数据内插方法相比，对地形可视性信息获取的准确性和效率影响最小，为平衡观察点设置问题解决过程中时间效率和准确度之间的关系，最终有效地解决观察点设置问题提供了数据基础。 最后，从智能算法和地形数据相结合的角度出发，提出了一种基于ISA和DCTI相结合的观察点设置问题多分辨率处理方法(Multi-Resolution Processing method, MRP)。新方法将模拟退火算法的逐次退火特点和地形数据的多分辨率表示充分结合，达到了发挥算法数据相结合的综合优势的目的。与现有单纯基于模拟退火算法的解决方法相比，在问题解决准确度保持不变的前提下，基于MRP方法的观察点设置问题解决的平均耗时减少85%~95%，为实际工程应用问题的解决提供了一条重要途径。The observer sitting problem is an important problem in terrain visibility analysis. The research on this problem can play an important role in many fields such as spatial information aid decision, communication, tourism, wild animal protection, and so on. The research work in this dissertation is based on the conclusion and the analysis of existed research outcome for this problem. Firstly, aiming to solve the disadvantage that is the existed methods almost analyze this problem only from intelligent algorithm aspect or only from terrain data representation aspect, a new problem related solution framework is developed, which combines the algorithm’s and data’s analysis. This framework is to consider the cooperation of intelligence algorithm and data representation in the solving process for observer problem, and the aim is to improve the solving process’ accuracy and efficiency. Secondly, based on the characteristic of observer sitting problem itself and combining with the basic theory and method of subjected cloud theoretic, a problem related improved simulated annealing algorithm (ISA) has been proposed, whose improvements concludes the new annealing function, a new temperature generating process and a new status producing process. The ISA holds the same characteristics of traditional SA such as stable orientation and the acceptation of bad solution being harder and harder as the annealing temperature descending from one side, and has the specialties that are annealing temperature’s continuous and random variety and implied “Re-Annealing” process which can refuse the bad solution and accelerate the ISA’s conferencing speed from the other side. Thirdly, based on the influence degree of the factors such as the terrain data’s resolution and errors for the observer sitting problem’s solving accuracy, a discrete cosine transformation based terrain data interpolation method (DCTI) has been provided. The DCTI makes the interpolation process from traditional spatial domain to frequency domain and utilizes the “entropy preservation characteristic” and “energy compression characteristic”, which improve the interpolation’s efficiency and accuracy. Compared with other existed terrain data interpolation methods, DCTI has the smallest influence for the visibility information, which lays the foundation for the making balance between the efficiency and accuracy of observer sitting problem and solving this problem finally. Finally, from the combination of algorithm and data aspects, an ISA and DCTI based multi-resolution processing method (MRP) for observer sitting problem has been illustrated, which combining the simulated annealing algorithm’s characteristics and the terrain data’s multi-resolution representation, in order to get the aim that exerting the power of algorithm’s and data’s advantage. Compared with the existed method which is only based on the traditional simulated algorithm, the time cost of the MRP method reduces 85%~95% under the condition that the precision does not deteriorate, which provides an important approach to solve the actual engineering application problem

design and implementation of ship-borne semi-physical simulation information display system

针对船载综合信息显示系统在实体船舶内开发不方便的问题,提出了一种半实物仿真系统的设计与实现方法。结合"科学三号"海洋科学考察船的综合信息显示系统的设计和开发过程,从体系结构、信息流程和实现方法3个方面对半实物仿真系统的设计和实现过程进行了探索。实践结果表明,这种半实物仿真系统一方面可以为实际系统的体系结构、信息流程设计提供支持,另一方面可以为实际系统应用软件的开发提供较为真实的环境,有效的缩短开发时间和降低开发风险

application of functional language method in interactive web programming

网络应用程序中为了保持程序的交互性,服务器端的控制程序如CGI(command gateway interface)程序需要在不同的脚本程序之问切换,这样不可避免的会造成控制信息的丢失.为了避免这些问题,介绍了将函数式程序设计语言的一些方法,如Continuation、CPS(eontinuationpassing style)等,并将它们应用到网络程序设计中,不仅简化了设计过程,也提高了程序的安全性,并可以在更一般的语言中实现

提高中国软件产业自主创新能力的科技政策思考

当前中国软件产业发展面临着难得的机遇和广阔的市场空间,快速提升中国软件产业自主创新能力是促进中国软件产业发展的关键,也是促进经济可持续发展的必由之路。是促进软件企业联盟,增加软件研发投入力度,营造自主创新的外部环境等措施

全球数字广播系统音频编码器的软件实现

全球范围的数字广播系统DRM(Digital Radio Mondiale),是一种针对30MHz以下频段的数字声音广播系统。和传统广播系统相比,DRM数字广播系统在声音质量上是模拟调幅广播无法比拟的。这其中的关键之一在于DRM系统引入了新的信源编解码技术——MPEG-4标准的AAC(Advanced Audio Coding,先进音频编码)。在分析符合DRM标准的AAC音频编码器原理基础上,提出了一种改进的离散余弦变换算法,并在PC上实现了基于该算法的AAC音频编码器。实验表明,该软件编码器能够满足D