数字区调新技术新方法—RS_OrthoMapper系统研制开发

为了适应当今数字区调工作的需要,开发一套3S技术有机结合简单实用的数字区调野外工作平台或软件系统,已成为燃眉之急。论文介绍了数字区调新技术新方法--RS_OrthoMapper系统研制与开发的基本需求、系统的总体结构与设计、系统实现等,并给出了系统中一些重要的逻辑视图。该系统在西藏昌务场和青海阿拉克湖等地区数字区调填图中示范应用,获得良好效果。     

Determination of alkylbenzyldimethylammonium chlorides in river water and sewage effluent by solid-phase extraction and gas chromatography/mass spectrometry

This study presents a modified method to analyze alkylbenzyldimethylammonium chlorides (ABDACs) in river water and sewage effluent. The method involves mixed samples with linear alkylbenzenesulfonates (LAS) as a counterion to enhance the extraction of ABDAC residues from an RP-18 solid-phase cartridge by formation of hydrophobic ion-pair complexes. The ABDACs were then eluted with methanol-ethyl acetate (1:1, v/v) and formed to their corresponding alkyldimethylamines by the Hofmann degradation with potassium tert-butoxide. The alkyldimethylamines were then identified and quantitated by gas chromatograph/mass spectrometry (GC/MS). The results indicate that, in the presence of LAS, debenzylation of ABDACs occurs selectively at a temperature higher than 90 degrees C to produce the corresponding nonionic alkyldimethylamines. The method proposed herein provides a high precision and sensitivity for ABDACs, to quantitation at < or =0.1 microg/L in 500 mL of the water samples. The average recovery of ABDAC spiked water samples was 95% with relative standard deviations (RSD, n = 7) of 9%. The RSDs of three replicate environmental sample analyses ranged from 5 to 11%. Direct HPLC method was applied to evaluate the GC/MS method, and compatible results were observed.     

A variable neighborhood search for minimizing single machine weighted earliness and tardiness with common due date

Although the concept of just-in-time (JIT) production systems has been proposed for over two decades, it is still important in real-world production systems. In this paper, we consider minimizing the total weighted earliness and tardiness with a restrictive common due date in a single machine environment, which has been proved as an NP-hard problem. Due to the complexity of the problem, metaheuristics, including simulated annealing, genetic algorithm, tabu search, among others, have been proposed for searching good solutions in reasonable computation times. In this paper, we propose a hybrid metaheuristic that uses tabu search within variable neighborhood search (VNS/TS). There are several distinctive features in the VNS/TS algorithm, including different ratio of the two neighborhoods, generating five points simultaneously in a neighborhood, implementation of the B/F local search, and combination of TS with VNS. By examining the 280 benchmark problem instances, the algorithm shows an excellent performance in not only the solution quality but also the computation time. The results obtained are better than those reported previously in the literature.     

Decision support for risk analysis on dynamic alliance

Dynamic alliance has been considered a temporary organization of member enterprises formed to pool their core competencies and exploit fast changing market opportunities. Although many problems on dynamic alliance such as partner selection, operation management, information exchanges and their standards, etc., have been investigated, the risk management of dynamic alliance has not received deserved attention until now. For risk evaluation is the most important phase of risk management, so this paper is mainly concerned with the risk evaluation problem. Various kinds of risk factors that affect the operation of alliance are identified, and their levels are measured by three parameters such as risk occurrence likelihood, consequence severity and risk control degree. These parameters are expressed by trapezoidal fuzzy numbers. Furthermore, risk evaluation is regarded as a multiattribute decision-making (MADM) problem with uncertainty. A new evaluation approach based on the framework of the evidential reasoning (ER) is proposed. Finally, a numerical example is given to illustrate the application of this approach in the process of risk evaluation.     

线性流形上一类矩阵方程的最佳逼近问题

本文研究矩阵方程AXB=C在线性流形Γ={X∈SR~(n×n)|||TX-Y||=min}上的最佳逼近问题,得到了问题解的表达式．此外,还给出了求解该问题的数值算法和算例．     

A novel key agreement protocol based on chaotic maps

Based on the semi-group property of Chebyshev chaotic map and some effective improvements of our original protocol, we propose a novel chaotic maps-based key agreement protocol which is proved to be secure, feasible and extensible.     

A novel image watermarking scheme based on amplitude attack

This paper presents a novel image watermark scheme based on the characteristics of amplitude attacks. First of all, the analysis of amplitude attacks is performed. Then the amplitude attacks are categorized into three types: positive attack, negative attack and random attack. Finally, based on these attack types, we design three corresponding detectors. The detectors remove the unreliable discrete cosine transform (DCT) coefficients in the attacked image so that only reliable coefficients are used for the extraction of the watermark embedded. The experimental results indicate that the proposed technique improves robustness significantly without sacrificing the false alarm rate.     

基于GPRS的水文数据采集系统的设计

利用通用分组无线业务(GPRS)技术实现水文数据的采集是水文部门选择的通信手段之一.文章描述了基于GPRS技术的水文数据采集系统的组成,工作站与集中器以及采集器之间的数据传输原理,介绍了监控中心工作站应用软件的设计方法,同时,给出了工作站应用软件的主界面设计图.     

中板厂钢坯氧割渣在线清除系统的制作及应用

介绍了柳钢中板厂钢坯氧割渣的在线清除系统的组成及其生产性能。     

户式空调新风引入方式对室内热环境的影响

选择典型的装有分体空调的居室和办公室,对多种新风不同引入方式下室内的环境参数作了测试,比较并分析了新风引入方式对室内热环境的影响,提出了采用低位大新风量高风速引入方式室内温度场不平均度最小,即温度环境最好,并对所得结果进行了的理论分析。