急切分类与懒散分类的研究

本文主要以决策树归纳算法和 k-最近邻分类算法为例 ,对数据挖掘中的急切分类算法和懒散分类算法进行了比较 ,并介绍了一种具有这两类分类算法优点的新的分类算法及该算法的实现方法     

高效同步复制模型的研究

数据复制是分布式数据库中常用的方法,以提高数据的可用性和系统的性能。文章引入若干技术解决同步复制方法的缺陷,提出了一个高效同步复制的模型,给出了事务的具体处理过程。     

Lazy和Eager分类算法的比较研究

数据挖掘的两个高层目标是预测和描述,这个过程中分类算法的应用是非常广泛的。分类算法在机器学习领域中可以分为Lazy和Eager两种类型,分别具有不同的算法特点。文章基于实验对这两种类型的分类算法进行了分析,概括出适宜两种类型的环境条件,旨在提出实际应用中进行算法选择的经验性结论。     

基于组通信技术的同步复制方法的研究

针对同步复制方法本身的缺点提出一种新的研究思想，即引入组通信技术，利用组通信技术中关于转发信息的定序性质，借助于类队列的并发控制思想，很好地解决了复制领域中的数据一致性及通信量的问题。     

Eager and delayed contract monitoring for call-by-value and call-by-name evaluation

Contracts are a proven tool in software development. They provide specifications for operations that may be statically verified or dynamically validated by contract monitoring.We investigate the properties of contract monitoring for languages with contracts and effects using a monadic semantics. We study three combinations of evaluation orders and contract monitoring styles: call-by-value and call-by-name with eager monitoring and call-by-name with delayed monitoring.In each case, an effect system ensures that contract monitoring does not change the meaning of a program and guarantees that contract monitoring is idempotent. The monadic semantics enables us to study design choices, to formalize implementations, to pinpoint the differences between contracts in the three combinations, and to verify algebraic laws.     

数据流Eager传输:一种分布式流体系结构中的性能优化技术

分布式流体系结构扩展了分布式环境下的流计算模型,可在互联网上为大数据计算应用提供高效低成本的运行环境。互联网中较长的通信开销制约了计算性能。提出了一种数据流Eager传输的性能优化技术,以挖掘计算与通信之间的并行性,隐藏通信延迟。在分布式流体系结构原型系统中实现了该技术。实验结果表明,应用程序采用该优化技术之后的平均时间开销减少了19.58%,表明该优化技术能够显著提高应用的性能,具有良好的应用前景。     

On The Detection of Test Smells: A Metrics-Based Approach for General Fixture and Eager Test

As a fine-grained defect detection technique, unit testing introduces a strong dependency on the structure of the code. Accordingly, test coevolution forms an additional burden on the software developer which can be tempered by writing tests in a manner that makes them easier to change. Fortunately, we are able to concretely express what a good test is by exploiting the specific principles underlying unit testing. Analogous to the concept of code smells, violations of these principles are termed test smells. In this paper, we clarify the structural deficiencies encapsulated in test smells by formalizing core test concepts and their characteristics. To support the detection of two such test smells, General Fixture and Eager Test, we propose a set of metrics defined in terms of unit test concepts. We compare their detection effectiveness using manual inspection and through a comparison with human reviewing. Although the latter is the traditional means for test quality assurance, our results indicate it is not a reliable means for test smell detection. This work thus stresses the need for a more reliable detection mechanism and provides an initial contribution through the validation of test smell metrics.     

土地复垦工程的遥感评价

现阶段,我国土地复垦及其评价工作越来越受到重视。结合课题研究工作介绍了土地开发整理遥感评价方法。通过实验区域的选取、实验区相关实地数据的收集、遥感影像选择、试验区遥感影像的处理和解译、影像信息分类等研究工作,提取了土地复垦开发整理项目的工程量指标,建立了土地复垦项目的工程量评价体系,分析提取的成果与实地数据一致,证明遥感评价方法有效可行。     

磁盘坏簇分析及其回收

本文分析了磁盘的簇管理、坏簇分类及产生原因;探讨了充分回收坏簇的方法;给出了针对双面高密软盘的实用程序。     

Eager interpretation of on-line hand-drawn structured documents: The DALI methodology

On-line hand-drawn structured document interpretation is a complex problem of pattern recognition. This paper deals with eager strategies for such purpose, i.e. consisting in updating the analyzed document after each input stroke and providing a corresponding feedback to the user. We have designed a new class of visual grammars for the modeling of structured document composition: the context-driven constraint multiset grammars (CD-CMG). Their main originalities are to model the structural context in which a production can be reduced and to take into account the hand-drawn nature of the considered data. Its associated parser exploits the formalized knowledge for predictive purposes and couples bottom-up and top-down strategies. Their context-sensitiveness helps reducing significantly the combinatory associated to the analysis process. We use the fuzzy set framework to evaluate each possible interpretation on a qualitative way. Reject options are exploited to increase the decision making robustness and to detect the need for stroke segmentation. The parser is also able to wait for more information before making a decision by using a branch and bound algorithm. In this paper, we provide experimental results showing that the method is efficient enough to be used in real-time applications. We illustrate this point by focusing on a commercialized pen-based system that is based on the DALI method we present in this paper.     

农垦系统应急物资设施选址问题研究磁

论文对农垦系统应急物资储备库选址问题进行研究,综合了 P-中值模型、P-中心模型、覆盖模型等一般选址模型的优缺点,同时考虑到应急设施选址的效率性、公平性和成本等多方面因素,建立了一个多目标决策模型。该模型采用线性加权和法求解,得出应急设施的最优选址点。经齐齐哈尔垦区应急行动检验,多目标决策模型的计算结果科学合理、经济可行,为应急设施选址决策提供了有效依据。     

莫索湾垦区自来水厂监控中心软件设计

该文针对自来水厂自动化监控的需求,从整体结构和监控界面的组成分析系统的功能,利用Kingview组态软件进行监控系统设计.监控中心使用组态软件的各种组态功能对水厂取水泵房、各清水池及加压泵房等实时监控,对各单元生产现场实时参数采集和显示,并通过报表组态功能生成水厂数据报表.根据在莫索湾垦区自来水厂的实际使用情况,值班人员能够实时远程监控水厂各工作环节,验证该系统能够安全可靠运行.     

高效的闪存空间分配与回收方法

随着闪存容量的不断增长以及企业计算、Web数据管理等新型闪存应用的出现,如何管理大容量闪存的存储空间已成为一个迫切需要解决的问题.针对已有闪存空间管理方法存在的低垃圾回收效率和低空间利用率等问题,提出了一种新的高效的闪存空间分配与回收方法,称为BSFTL.BSFTL将数据块区分为冷热两种类型并采用不同的存储管理方式.实验结果表明,BSFTL方法可以显著降低垃圾回收的代价,同时提供了较高的闪存空间利用率.     

一种新型复垦地再造耕作层材料

鉴于目前以覆土为主的复垦工作由于覆土来源难以保证而受到限制的问题,拟寻求一种适合农业种植的新型复垦地再造耕作层材料。本研究进行了粉煤灰与有机物料糠醛渣组配的基质进行作物种植的试验,探讨了这种基质进行作物种植的可行性和主要化学性质的变化。结果表明:粉煤灰和糠醛渣以4:1的质量比组配的新型材料作为复垦地再造耕作层进行作物种植,只要选择合适的植物,产量和品质都不受影响,基质的性状得到改善,可以满足大多数植物的生长,重金属含量不超标,可以取得较高的经济、环境和社会效益,为矿区土地复垦提供了新的理论和方法。     

基于SBAS-InSAR技术的围填海区域地面沉降监测

以围填海活动为代表的沿海快速城市化过程,是引起地面沉降的重要影响因素之一.研究聚焦沿海围填海活动热点区域广州市南沙区,使用2015年6月～2018年4月共34景Sentinel-1数据,应用SBAS-InSAR技术,揭示了南沙区在研究时段内地面沉降的时空变化格局及演变特征.结果表明:①南沙区整体呈现持续沉降的趋势,沉降...     

基于改进遗传算法的土地复垦规划空间优化

土地复垦空间优化是对复垦区土地再利用类型进行数量配置和空间布局,是土地复垦的重要内容和主要方面.根据土地复垦空间优化问题的特性对传统遗传算法添加了小生境算法、自适应参数算法和倒位算法等改进算法,构建了土地复垦空间优化模型,并将遗传算法和GIS融合,增强了复垦土地空间结构优化的空间处理能力.以北京市门头沟区矿业废弃地复垦空间优化为例进行仿真,结果表明:改进的遗传算法更加准确高效,对空间布局的优化结果与门头沟区实际情况相符.     

MATLAB在矿区土地复垦中的应用

随着矿区土地复垦研究的深入,数据处理与分析的工作量越来越大。MATLAB是一套高性能的数值计算和可视化软件,在许多领域得到应用。论文介绍了利用MATLAB进行复垦用地结构优化及土地复垦条件分类的方法,通过实例说明,它可明显提高土地复垦数据处理与分析的效率,在矿区土地复垦中有广泛的应用前景。     

Efficient and Reliable Lock-Free Memory Reclamation Based on Reference Counting

We present an efficient and practical lock-free method for semiautomatic (application-guided) memory reclamation based on reference counting, aimed for use with arbitrary lock-free dynamic data structures. The method guarantees the safety of local as well as global references, supports arbitrary memory reuse, uses atomic primitives that are available in modern computer systems, and provides an upper bound on the amount of memory waiting to be reclaimed. To the best of our knowledge, this is the first lock-free method that provides all of these properties. We provide analytical and experimental study of the method. The experiments conducted have shown that the method can also provide significant performance improvements for lock-free algorithms of dynamic data structures that require strong memory management.     

开垦对草甸土有机碳的影响

本文利用经典统计学和地统计学相结合的方法,选取科尔沁沙地东南缘草甸土两块10×10m的样地为例,分析了草地开垦8a后的耕地耕作层土壤有机碳含量和空间分布格局的变化,结果表明:草地与耕地表层(0～10cm)土壤有机碳含量差异不显著,草地亚表层(10～20cm)土壤有机碳含量低于耕地(p<0.05);草地与耕地表层和亚表层土壤有机碳空间分布格局具有明显差异,表现为草地的表层和亚表层的结构异质性分别大于耕地,分数维小于耕地,空间依赖性强于耕地,空间分布格局的破碎程度弱于耕地。耕地表层与亚表层土壤有机碳含量差异不显著(p<0.05),但空间结构特征和空间分布格局存在明显的差异;而草地表层与亚表层土壤有机碳含量差异显著(p<0.05),但空间结构特征和空间分布格局比较相似。因此,开垦不仅影响草甸土有机碳含量的高低,而且影响其空间结构特征和分布格局。这对进一步了解草地开垦对土壤有机碳及全球碳循环和气候变化的影响具有重要意义。