基于中间件技术的GIS中并发控制

当前GIS大都采用了关系数据库作为空间数据的存储媒介，但关系数据库支持的并发控制并不完全适用于空间数据，提出了一个在GIS应用层运用中间件技术实现对二维空间数据并发控制的方法，在封锁粒度方面，采用了面向四叉树封锁，在封锁类型和封锁协议中，扩充了原有的锁，增加了强弱意向锁，使其更加协调各种不同级别的封负的并发控制，在封锁协议中，由于采用了中间件技术，只需利用一级封锁协议。     

尼龙-11粉末涂料

本文简要地介绍了我国粉末涂料的发展概况，并概述了热固性和热塑性粉末涂料的应用领域．文章重点介绍了尼龙－１１粉末涂料的优点及其制造法，阐述了其在管道防腐、船体防护和建筑行业等领域的应用     

A Software Tool for Automatically Verified Operations on Intervals and Probability Distributions

We describe a software tool for performing automatically verified arithmetic operations on independent operands when the operands are intervals, or probability distribution functions, or one operand is an interval and the other is a distribution. Intervals and distributions are expressed using the same technique, so the algorithms do not need to distinguish between intervals and distributions in their operation. The tool can calculate common arithmetic operations with guaranteed results (as well as confidence limits on a distribution if the distribution is empirically estimated from samples).A previous paper [1] discusses the concepts, algorithms, and related work. Here we emphasize a software tool that implements the algorithms, interacts with the user via a graphical user interface, and saves, retrieves, and prints the results of its calculations.     

小方坯连铸中包长寿及定径水口快速更换技术

小方坯连铸中间包定径水口快速更换技术是提高连浇炉数的有效手段，与之配套的中间包长寿技术是实现高连浇炉数的保证。介绍了该项技术在首都钢铁集团第三炼钢厂的研制推广和应用情况，并阐述了快速更换机构的改进和中间包耐材的优化。     

A Multivariate T2 Control Chart for Skewed Populations Using Weighted Standard Deviations

This paper proposes a heuristic method of constructing multivariate T² control charts for skewed populations based on ‘weighted standard deviations’, obtained by decomposing the standard deviation into upper and lower deviations according to the direction and degree of skewness. The proposed method adjusts the variance–covariance matrix of quality characteristics and modifies the ellipsoidal probability density function contour of the multivariate normal distribution to a shape similar to that of the skewed distribution. False alarm rates and out‐of‐control average run lengths of the proposed control chart are compared with those of the standard control chart for multivariate lognormal, Weibull and gamma distributions, and the results show that considerable improvement over the standard method can be achieved when the distribution is skewed. Copyright © 2003 John Wiley & Sons, Ltd.     

Comparison of corrosion behavior of zirconium bombarded with self-ion and molybdenum ion

In order to study the effects of zirconium and molybdenum ion bombardment on the aqueous corrosion behavior of zirconium, one group of specimens was implanted with zirconium ions with ions surface densities ranging from 1 × 10¹⁵ to 2 × 10¹⁷ ions/cm² at about 170 °C, using a metal vapor vacuum arc (MEVVA) source operated at an extraction voltage of 50 kV. The other group of specimens was bombarded with molybdenum ion with ions surface densities ranging from 1 × 10¹⁶ to 5 × 10¹⁷ ions/cm² at about 160 °C, using a MEVVA source operated at an extraction voltage of 40 kV. The valence states and depth distribution of elements in the surface of the samples were analyzed by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES), respectively. Polarization curves measurement was employed to evaluate the aqueous corrosion resistance of the zirconium samples in a 1N H₂SO₄ solution. It was found that the aqueous corrosion resistance of zirconium implanted with 5 × 10¹⁶ Zr ions/cm² is the best in first group samples. For molybdenum ion implantation, the aqueous corrosion resistance of samples declined with raising ions surface densities. The natural corrosion potentials of zirconium samples bombarded with self-ions are more negative than that of the as-received zirconium. While, as for molybdenum ion implantation, the results are opposite. Finally, the mechanisms of the corrosion behavior of the zirconium samples implanted with zirconium and molybdenum ions are discussed.     

Preparation of CaS∶Eu~(2 ), Sm~(3 ) by Solid Reaction Method and Its Photostimulated Luminescence

Thereisanurgentneedonopticalstoragemateri alswiththedevelopmentoflaserandopticalstoragetechnologyinrecentyears .Electrontrappingopticalstoragematerials (ETM )isanewtypeofopticalstor agematerials .Theybasicallyarewide band gapⅡ Ⅵsemi conductorcompoundsdopedwithtwotypesofselectedrareearthelementsthathavegroundstatesandexcitedstateswithinthewidebandgapoftheⅡ Ⅵsemiconductorcompoundhostmaterials .Lighten ergyisstoredinthiskindofmaterialbyexposingittoultravioletorvisiblelightandisreleasedthro…     

丹东市个体私营经济发展态势分析

我市个体私营经济具有一定的经济基础,发展前景广阔,渐趋成为全市经济的重要组成部分。本文阐述了我市个体私营经济的现状,分析了发展中存在的问题,提出了加快发展所应采取的措施。     

臭氧降解低浓度四溴双酚A及生物毒性控制

为考察臭氧氧化技术对水中低质量浓度四溴双酚A的降解和毒性控制效能,利用臭氧反应装置研究不同pH和臭氧投加量条件下四溴双酚A(质量浓度为0.15 mg/L)的降解效果,考察反应过程中水样的急、慢性毒性和遗传毒性的变化规律及控制效果,分析毒性变化内在原因,并提出可能性降解机理.结果表明,当溶液pH为7.0、臭氧投加量为0.12 mg/L,四溴双酚A可被完全降解.反应初期,水样的急、慢性毒性迅速升高,原因主要是产生了毒性更高的有机中间产物;随着反应的进行,有毒中间产物被深度降解,急、慢性毒性均得到有效控制,且随着臭氧投加量的增加毒性控制得更快、更显著.当臭氧投加量为0.12 mg/L时,急性毒性在反应20 min时即可被完全控制,慢性毒性在反应60 min也被控制至0.76 TU,反应后水样的急、慢性毒性均满足排放标准.反应过程中水样的致突变比均小于2.0,不具有基因水平的遗传毒性.降解机理分析表明,臭氧降解四溴双酚A主要包括脱溴、β位断裂、加成、去羟基化、甲基化等反应过程.     

鞍钢3200m3高炉矿槽施工

介绍了鞍钢新1号高炉(3200m3)矿槽结构的设计原理及其所包含的钢结构、混凝土结构施工技术要点和质量控制,并作出了技术经济效果评述.