旧水泥路面共振碎石化技术的应用

本文以某旧水泥混凝土路面改造项目为例.对共振碎石技术进行了简单的概述和其特点描述,然后针对实际工程实例,对该技术进行应用,并对其效果进行分析.研究表明,在旧水泥路面改造项目中,使用共振碎石技术可以提高施工质量和效率,并值得工程中大量推广应用.     

粉砂的动力特性试验研究

结合某核电站取水明渠导流堤工程实例,对该工程地基土粉砂进行饱和固结条件下循环荷载试验以及共振柱试验,测定了动剪切模量、阻尼比与动剪应变幅的双曲线关系,分析了粉砂的动力变形特性.为评价导流堤地基的地震稳定提供参数,同时对类似工程场地的地震安全性评价有良好的借鉴和参考价值.     

钢结构异型柱框架的应用和发展

现主要介绍异型钢结构框架在高层建筑体系的应用,分析了该体系在钢结构能够利用的原因,对异型钢结构柱的优点进行了分析,并对各种异型柱的应用特点,进行了简单的分析和比较。     

粉砂的动力特性试验研究

结合某核电站取水明渠导流堤工程实例，对该工程地基土粉砂进行饱和固结条件下循环荷载试验以及共振柱试验，测定了动剪切模量、阻尼比与动剪应变幅的双曲线关系，分析了粉砂的动力变形特性。为评价导流堤地基的地震稳定提供参数，同时对类似工程场地的地震安全性评价有良好的借鉴和参考价值。     

解析共振光散射技术在无机分析中的应用

近些年来，随着科学技术的不断发展，越来越多的分析技术应用在化学领域中，而共振光散射技术就是近几年发展的较为迅速的一种分析检测技术，尤其是该分析技术能够在普通的荧光光度计上实现，操作十分简便，所以也受到了较多的关注。文章首先对共振光散射技术进行简要的分析，再对共振光散射技术在无机分析中的应用进行详细的论述。     

等离子共振光散射技术在食品安全检测中的应用

共振光散射（RLS）技术因其灵敏度好、实验仪器简单、检测方便等优点而倍受化学研究者青睐，因而得到飞速的发展，目前，共振光散射技术已成为分析化学领域中强有力的分析技术，本文将RLS进一步深化，用等离子共振光散射（PRLS）技术对环境重金属离子Ag^＋、食品中致癌物质苏丹红进行定性和定量表征，从实验中获取有用的信息，为RLS技术在临床诊断、环境监测、食品卫生监测等领域的应用提供理论和实验依据。     

轴向荷载作用下PEC组合柱试验及数值模拟研究

本文对PEC组合柱进行了轴向荷载作用下的静力试验研究,分析得到其试验过程特征和协同工作原理及组合作用,研究了该组合结构在轴向荷载作用下的破坏模式。对试验建立了ABAQUS有限元模型,通过与试验对比验证了模型的可靠性。采用此模型对4组共12根H型钢PEC柱进行分析,研究系杆间距、混凝土强度、型钢高厚比及含钢率对PEC柱轴向受力情况下的极限承载力以及其破坏形态的影响。结果表明:系杆间距与混凝土强度对PEC柱的受力性能影响并不明显;随着型钢高厚比的增加,其他条件不变时,PEC柱的变形能力不断增大;随着含钢率的增加PEC柱的极限承载力明显提升。     

浮选柱浮选金矿矿泥半工业试验研究

本文介绍了某金矿应用浮选柱浮选矿泥所进行的半工业试验过程及结果分析。通过试验及数据分析,表明了浮选柱适合该金矿浮选矿泥,并能够取得比较好的技术指标。     

某烟厂厂房结构可靠性鉴定与加固

通过对某烟厂厂房框架梁、板、柱混凝土裂缝及加固后混凝土又开裂的原因进行了检测鉴定,并对其重新加固处理做了简单介绍。     

浅谈异形柱框架结构在民用住宅设计中的应用

随着科学技术日新月异和社会经济的高速发展,人们的生活生产水平显著提高,从而促使了我国住宅建筑的发展。而在现代社会中随着人们的生活水平提高,人们对房屋建筑也提出了更高的要求。在现代的建筑工程中,随着建筑行业的蓬勃发展,建筑材料质量和施工工艺水平都有了大幅度提升,从而为现代的建筑工程建设打下了坚实的基础。在现代的建筑工程中,通常会应用到异形柱框架结构。异形柱框架结构在保证建筑工程质量的同时,还能够满足人们对建筑平面和空间的要求。本文通过对异形柱框架结构的深入研究,并对其在现代民用住宅设计中的应用进行了深入分析,然后提出了异形柱框架结构在民用建筑设计中应该注意的问题进行了详细的阐述,以供同行参考。     

Effect of mobile teaching on students who need special education

The purpose of this study is to test the mobile application designed for the teaching purposes of students who need special education. Many mobile applications and software are available for teaching, thus this study will point the effect of using such technologies in teaching activities as an assistive method to the teacher. The tests are done using our previously designed mobile application that is designed to teach the basic concepts. As it is indicated in the design, the process starts with the testing of the basic abilities of the children, therefore, our tests include these kind of pretests and after that testing phases that will measure the effect of the application to learning. Students who need special education are the focus of the study. The tests are carried out in a special education centre, in Nicosia, Northern Cyprus on two students. Test results show that the mobile application developed in its current form, is a good tool to assist the teachers to enhance and speed up the learning process.

     

Simultaneous optimal estimation in linear mixed models

Simultaneous optimal estimation in linear mixed models is considered. A necessary and sufficient condition is presented for the least squares estimator of the fixed effects and the analysis of variance estimator of the variance components to be of uniformly minimum variance simultaneously in a general variance components model. That is, the matrix obtained by orthogonally projecting the covariance matrix onto the orthogonal complement space of the column space of the design matrix is symmetric, each eigenvalue of the matrix is a linear combinations of the variance components and the number of all distinct eigenvalues of the matrix is equal to the the number of the variance components. Under this condition, uniformly optimal unbiased tests and uniformly most accurate unbiased confidence intervals are constructed for the parameters of interest. A necessary and sufficient condition is also given for the equivalence of several common estimators of variance components. Two examples of their application are given.     

超高性能混凝土研究与应用进展

为了进一步推动UHPC在实际工程领域的应用,本文从制备过程、力学性能、应用进展对超高性能混凝土基本力学性能研究成果进行了系统的阐述,并设置0%、1%、1.5%、2%、2.5%、3%、4%共7组不同体积的钢纤维掺量进行了试验。试验结果表明,随着钢纤维含量的增加,试块基体的延性有了很大的提高,且抗压强度和抗拉强度均有提高,并最终确定钢纤维的最佳含量为2%;而后就UHPC在国内外土木工程领域应用现状进行了总结和归纳,同时还对其未来进行了展望。     

Evaluating GARCH models

In this paper, a unified framework for testing the adequacy of an estimated GARCH model is presented. Parametric Lagrange multiplier (LM) or LM type tests of no ARCH in standardized errors, linearity, and parameter constancy are proposed. The asymptotic null distributions of the tests are standard, which makes application easy. Versions of the tests that are robust against nonnormal errors are provided. The finite sample properties of the test statistics are investigated by simulation. The robust tests prove superior to the nonrobust ones when the errors are nonnormal. They also compare favourably in terms of power with misspecification tests previously proposed in the literature.     

An Algorithm for the Consistent Inclusion of Partial Information in the Revision of Input-Output Tables

TRAS is a natural extension of RAS that utilizes information in addition to row and column totals to produce updated matrices that are consistent with known cells and aggregates of known cells. This paper provides a simple restatement of the TRAS algorithm developed in Gilchrist & St. Louis (1999) and then tests its effectiveness by applying TRAS to the matrices obtained after RAS adjustments have been completed. The incremental gains from the TRAS adjustments were statistically significant.     

注水井启动压力分层测试工艺

为清楚认识注水井各层段的启动压力和吸水指数,提高分层注水效果。针对目前油田中测试工艺存在的问题,研制了注水井启动压力分层测试工艺。本文介绍了管柱结构,使用方法、选井条件以及主要的配套工具。通过现场应用表明,该工艺较好地解决了启动压力分层测试问题,见到了良好的增油效果,为油田分层措施提供了可靠依据。     

对框架结构高层建筑梁柱节点的施工技术探讨

在高层建筑施工中,联系整个结构体系的枢纽是框架结构的节点,节点承受由梁端和柱端传递来的各种荷载的共同作用,但受力复杂。就框架节点处理技术的基础理论及在施工中的应用问题进行探讨,并提出注意问题。     

天然气放空分液罐的应用及改进

作业区、处理厂分别在各站点安装了分液罐,使天然气在放空前实现了进一步气液分离,并且在安装后做了现场性能测验及效果评价。结果表明:分液罐在放空解堵应用过程中有一定的分液能力,运行较为平稳,但由于天然气放空速度与其分离液量存在矛盾,分液效果不明显,在水化物堵塞阻火器或井站故障紧急放空情况下运行存在严重的安全隐患,文章对分液罐及其辅助设备进行改进,提出了合理化的建议。     

Evaluating the accuracy of value-at-risk forecasts: New multilevel tests

We propose independence and conditional coverage tests which are aimed at evaluating the accuracy of Value-at-Risk (VaR) forecasts from the same model at different confidence levels. The proposed procedures are multilevel tests, i.e., joint tests of several quantiles corresponding to different confidence levels. In a comprehensive Monte Carlo exercise, we document the superiority of the proposed tests with respect to existing multilevel tests. In an empirical application, we illustrate the implementation of the tests using several VaR models and daily data for 15 MSCI world indices.