Load Testing in Bridge Maintenance

Highway bridges are a crucial component in road transportation networks.These bridges must be maintained according to usage requirements regularly.Test results must be considered before devising a maintenance plan.Load testing is a vital method of assessing the quality and performance of highway bridges.The outcomes of these tests facilitate the formulation of maintenance plans.This article examines the definition of load testing,its significance,and the process of execution,with the goal of providing support for bridge inspection and maintenance.

Value of Charpy impact test results with sub-and half-size specimens extracted from overage steel bridge members

For the maintenance of steel bridges,the mechanical properties of steel used in the bridges must be elucidated.When enough dimensions of specimens cannot be extracted from the actual members,miniaturized specimens are used for evaluation.In the case of the Charpy impact test,sub-and half-size specimens are specified instead of full-size specimens of which the thickness is 10 mm.The value of absorbed energy and energy transient temperature obtained by Charpy impact tests with sub-size and half-size specimens were investigated from the viewpoint of maintenance of bridges in this study.The absorbed energy was not in proportion to the thickness of specimens of steel used in the actual overage bridges.The tendency of energy transient temperature obtained by thin specimens of the overage steel differed from that of the present steel.A method for evaluating the performance against brittle fracture occurrence based on the WES3003 criterion was examined.The results show the significance of evaluation based on the energy transient temperature for reasonable maintenance of bridges.

Farmers’ Practices for the Orchard’s Maintenance and Post-Harvest Treatment of Cocoa in Infiltrated Classified and Unclassified Zone of Méagui (South-West, Côte d’Ivoire)

An important part of Ivorian cocoa production comes from infiltrated classified forests. The objective of this study is to investigate orchard maintenance and post-harvest cocoa treatment practices used by cocoa farmers in infiltrated classified and unclassified areas of Méagui. To do this, 110 producers in two localities of the said zone were individually interviewed from February to April 2022, using a declarative questionnaire. It was found that cocoa orchards in the zone are aging. Nearly 68.55% of producers were heirs and 58.33% of those interviewed were under 46 years of age, with an average age of 43 years. Nearly 84.55% of the producers surveyed mainly use chemical insecticides to control the pests of greatest concern in these localities. Regarding the frequency of insecticide treatments, 11.82% of producers make 1 to 2 applications a year, 29.09% make 3 to 5 applications a year, and 43.64% make at least 6 applications a year. The active substances of the most used products belong to 99% of the Neonicotinoid and Pyrethroid families. Regarding cocoa harvesting and post-harvest operations, 93.64% of the producers carry out a single harvest/month;all do the shelling with mini machetes. Beans are fermented mainly in black plastic tarpaulins or in bags, for a period of 3 to 5 days (65.45%). Drying is done almost entirely (91.82%) on the black plastic tarp. This study shows that cocoa farmers in the areas surveyed do not respect the recommendations issued on phytosanitary practices and post-harvest treatment of cocoa. This non-compliance with the standards of good practices prescribed is particularly more accentuated in the locality located in infiltrated classified zone. It would, therefore, be judicious to revise or redefine the phytosanitary recommendations and carry out sensitization and training-follow-up programs for producers in this important cocoa production area of C?te d’Ivoire.

Farmers’ Practices for the Orchard’s Maintenance and Post-Harvest Treatment of Cocoa in Infiltrated Classified and Unclassified Zone of Méagui (South-West, Côte d’Ivoire)

An important part of Ivorian cocoa production comes from infiltrated classified forests. The objective of this study is to investigate orchard maintenance and post-harvest cocoa treatment practices used by cocoa farmers in infiltrated classified and unclassified areas of Méagui. To do this, 110 producers in two localities of the said zone were individually interviewed from February to April 2022, using a declarative questionnaire. It was found that cocoa orchards in the zone are aging. Nearly 68.55% of producers were heirs and 58.33% of those interviewed were under 46 years of age, with an average age of 43 years. Nearly 84.55% of the producers surveyed mainly use chemical insecticides to control the pests of greatest concern in these localities. Regarding the frequency of insecticide treatments, 11.82% of producers make 1 to 2 applications a year, 29.09% make 3 to 5 applications a year, and 43.64% make at least 6 applications a year. The active substances of the most used products belong to 99% of the Neonicotinoid and Pyrethroid families. Regarding cocoa harvesting and post-harvest operations, 93.64% of the producers carry out a single harvest/month;all do the shelling with mini machetes. Beans are fermented mainly in black plastic tarpaulins or in bags, for a period of 3 to 5 days (65.45%). Drying is done almost entirely (91.82%) on the black plastic tarp. This study shows that cocoa farmers in the areas surveyed do not respect the recommendations issued on phytosanitary practices and post-harvest treatment of cocoa. This non-compliance with the standards of good practices prescribed is particularly more accentuated in the locality located in infiltrated classified zone. It would, therefore, be judicious to revise or redefine the phytosanitary recommendations and carry out sensitization and training-follow-up programs for producers in this important cocoa production area of C?te d’Ivoire.

Analysis on Effectiveness of Testing and Evaluation of Bridge Repair and Reinforcement

Bridge engineering is an important part of basic engineering in today’s transportation field,and its quality and performance have a vital impact on the improvement and development of modern transportation engineering.With the continuous development of transportation engineering,the maintenance and reinforcement of existing bridges are also being given more emphasis.In order to scientifically evaluate the effectiveness of bridge maintenance and reinforcement,this paper analyzes its detection and evaluation,including the significance,key points,and main methods of detection and evaluation.Therefore,this analysis aim to provide some reference for the maintenance and reinforcement and the quality improvement of bridge engineering.

水平受荷桩“p-y+M-θ”分析方法

中国近海海上风电机组开发建设中,大直径单桩基础形式使用占比超70%。现行p-y曲线设计方法主要适用于小直径柔性桩,对大直径单桩侧向及桩底受荷描述能力不足,导致其严重低估刚柔性桩和刚性桩(分别常用于中国和欧洲的近海风电工程)的变形和承载能力,过于保守的设计给海上风电降本带来挑战。为此建立了能以统一的方式预测柔性、刚柔性和刚性单桩水平单调受荷响应的“p-y+M-θ”模型,并将该模型推广到循环荷载下单桩的响应分析。通过与相关试验结果比对发现,“p-y+M-θ”模型能较为准确地预测桩基水平加载响应。力图为水平受荷单桩工程设计提供简洁而可行的响应分析方法。

Comparative Study on Nitrogen Metabolism and the Nitrogen Maintenance Requirement in Lohmann Brown Roosters and Layers

The objective of this study was to in- vestigate the effect of dietary protein level on nitrogen retention and compare nitrogen metabolism in Lohm- ann Brown adult roosters and layers. The nitrogen ma- intenance requirement （Nm ） was determined based on the nitrogen balance. Thirty Lohmann Brown adult roosters and 30 laying hens at 27 weeks of age were randomly divided into five groups of six birds per group. The birds were fed with one of five diets con- taining 10.46%, 11.77%, 13.79%, 16.77% or 18.29% of crude protein. Nitrogen intake, nitrogen retention and nitrogen retention efficiency were higher in roost- ers than in laying hens, and the average nitrogen re- tention rate for groups fed with CP level of 11.77%, 13.79%, 16.77% and 18. 29% was improved by9.14%. The nitrogen maintenance requirement for Lohmann Brown roosters and laying hens at 27 weeks of age were 0.4245 g/d and 0.5059 g/d, respective- ly, and Nm based on average body weight （BW） and metabolic body weight （ BW^Ts ） was 0.2364 g/kg BW and 0. 2739 g/kg BW~＇75 for laying hens and 0. 2754 g/kg BW and 0. 3208 g/kg BW^72 for roost- ers, respectively. The regression equations for daily N gain （NB, protein accretion） vs. daily N intake （NI ） for Lohrnann Brown layers and roosters were NB = 0.3743NI -0.1589（R2 =0.79） and NB =0.6228NI - 0.3151 （ R2 = 0.85 ）, respectively. The results of this study indicate that nitrogen intake and nitrogen reten- tion at the same dietary CP level were higher in roost- ers than in laying hens.

4 m×3 m风洞大迎角机构上位机软件

针对大迎角机构机械装置、控制硬件的改造升级,基于Labview框架平台设计编写上位机控制软件。优化更新基于TCP/IP协议的Socket通信,增设虚拟支杆设定、模型防碰撞识别等功能。编制的控制软件已成功应用于气动中心4 m×3 m低速风洞大迎角试验。结果表明,该软件有效提升了试验质量效率和设备运行安全。

基于SG-I6000 2.0+CMBD的电力智能运维系统设计与实现

为促使电网公司运维工作规范化、便捷化,提高电网运维效率,在原有SG-I6000 2.0系统架构基础上,融入配置管理数据库(CMBD),构建基于SG-I6000 2.0+CMBD的电力智能运维系统。该系统自上而下分为应用层、中台服务层和运维感知层,相比原系统新增了资源配置、流程服务、健康履历、自动审计、业务流微应用、构建自主流程微应用、资源全过程管理等。并发测试结果表明,新系统最大可承受1000个并发用户同时使用的需求。压力测试结果表明,在最大500个用户数量同时操作情况下,平均事务响应时间仅为40.8 s,相比原系统降低了63%,运维效率得到显著提升。

基于M估计强混合重尾序列结构变点的鲁棒检验

针对强混合重尾序列结构变点的检测问题,为避免因序列重尾性导致最小二乘估计产生偏差,文章提出了基于M估计的比值型检验统计量,用于检测重尾序列位置结构变点。在一般约束条件下证明了原假设下统计量的极限分布是布朗运动的泛函,并得到备择假设下的一致性。针对因序列相依性导致的经验水平扭曲现象,采用Block Bootstrap抽样方法获得了更为准确的临界值,有效提高了检验功效。数值模拟结果显示,在Block Bootstrap抽样方法下基于M估计的比值型检验在强混合重尾序列结构变点检测中能较好地控制经验水平,经验势也较合理。最后,通过一组汇率数据验证了所提检验方法的可行性。

五道沟地区近50年浅层地温(0~40 cm)变化规律分析及预测模型构建

浅层地温对作物种子发芽和生长具有重要作用。本文利用五道沟实验站近50年浅层地温(0~40 cm)实测资料,采用Mann-Kendall检验、斯皮尔曼相关性分析、气候要素变化趋势分析和其他气候要素筛选,分析研究区近50年浅层地温年、季尺度演变规律,提出浅层地温与气温、降水量、风速、日照时数和水汽压力差多气象要素的相关性,并构建了多元回归预测模型。结果表明,(1)年际变化上,研究区域各层地温均呈现上升趋势,各层地温的变化趋势基本一致。各季浅层地温变化趋势不尽相同,冬季地温趋势率最大,春季、夏季和秋季浅层地温升温趋势在较小范围内波动。(2)在Mann-Kendall突变检验中,0、10、15、20和40 cm浅层地温分别在2012、2018、2015、2017和2017年发生突变,在这些年份发生突变后地温有明显上升趋势。(3)冬季浅层地温与气温呈极强正相关关系(R2>0.8),不同季节下研究区风速、日照时数和水汽压力差与浅层地温存在一定的线性相关性。(4)建立了不同季节浅层地温与各气候因子预测模型,并且用该模型对2022年月平均地温进行拟合检验,该模型精度较高,可用于研究区地温预测。

Framework for Observing the Maintenance Needs, Runtime Metrics and the Overall Quality-in-Use

The post-release maintenance is usually the most expensive phase in the software product lifecycle from the first design concepts to the end of product support. To reduce the costs related to post-release maintenance, we propose a run-time framework for measuring software quality characteristics applying the ISO/IEC 25000 software quality and software quality in use models as the starting point. Measurement probes are linked into the software during the development phase and used to collect quality information during the run time. As a proof-of-concept, we implemented measurements in an open-source software project to demonstrate the utility of the framework. As a result, this paper presents a framework for collecting runtime metrics and measuring software quality-in-use with a systematic interface. Additionally, examples of measurement scenarios are presented.

有Bernoulli检修与顾客进入控制策略的M/G/1可修排队的可靠性

本文研究一个具有Bernoulli检修与顾客进入控制策略的M/G/1可修排队模型,其中服务台在服务顾客期间可能发生故障.Bernoulli检修与顾客进入控制策略是指每当系统变空时依概率p(0≤p≤1)进入检修,或者依概率(1−p)不进入检修而是等待下一个顾客进入系统后直接开始服务,而且在系统的检修期内至多允许N个顾客进入.运用更新过程理论、全概率分解技术与拉普拉斯变换工具,我们对系统的一些可靠性指标进行了讨论,例如时刻t服务台处于故障状态的概率、在(0,t]内服务台的平均失效次数等等.最后通过数值计算研究了一些系统参数对系统可靠性指标的影响.

一种DSM压力传感器快速检测装置研制

DSM作为璇玑系统的中控,其压力传感器参数测量的准确度,对于钻井参数控制起到参考作用,直接关系到井下设备作业质量。该装置可在电路骨架维保时进行井眼、环空两个传感器的压力测试,从而提升维保质量,与此同时,不需要单独拆卸压力传感器及主控板前往压力标定台进行压力测试,提升维保效率。

A Prospective Study of Maintenance Electroconvulsive Therapy in an Elderly Depressed Population

Objective: This study was conducted to discern the efficacy of maintenance electroconvulsive therapy (M-ECT) in a population of depressed elderly individuals with treatment-resistant depression. Methodology: Twenty-nine (N = 29) individuals over the age of 65 years of age and older were assigned to a control or treatment group on the basis of their decision to receive M-ECT (treatment group) or to refrain from receiving the treatment (control group). A battery of psychometric tests designed to measure severity of depression, quality of life, and cognition were administered at baseline as well as at 6-month and 1-year intervals. Results: Statistical analysis of the data indicated no significant differences in the efficacy of M-ECT between the control and treatment groups in any of the tests administered during the participation of the study. Conclusion: The results of the study suggest that there is no added benefit for patients administered M-ECT. However, study sample size and availability of alternative treatment regimens for the control group limit generalizability of these findings and warrant further investigation.

最终接头M止水带比例缩尺水密推拉试验研究

深中通道最终接头止水密封系统由一道M止水带和一道充气止水带组成。M止水带一端安装在扩大段,另一端安装在推出段。由于M止水带体积巨大现场实际工况复杂,因此进行最终接头M止水带比例缩尺水密推拉试验。M止水带比例缩尺试验分为水密试验和推拉试验,推拉试验工装由水密试验工装改造而成。2次试验可以直观地在陆上观察到M止水带的水压承受情况及推拉后M止水带变化状态,2次试验分别验证了M止水带在实际应用中的水密性能及伸缩回弹性能,结合试验工况可以制定相关措施,有效避免了实际应用中出现突发问题。

基于M-K检验法的青海高原降水特征分析

利用青海省49个气象站1961-2018年降水资料,将青海省分为3个区域,采用单变量和多变量Mann-Kendall(M-K)检验法,分析了青海省降水时空变化特征。结果表明:1961-2018年,青海省年平均降水量总体呈上升趋势;年平均降水量、年平均降水日数、年最大降水量的空间分布基本保持一致,呈由东南向西北递减趋势,三者最高在黄河源地区、祁连山东段、青海省东部地区和三江源东部地区,其次为三江源中西部地区,最低值在柴达木盆地。青海省降水量总体呈上升趋势主要是由Ⅰ区(柴达木盆地和祁连山区)和Ⅲ区(三江源地区)降水量显著上升引起的,而Ⅱ区(青海省东部地区)降水量变化不显著。在整体趋势分析方面,单变量检验只能分析单个变量的变化趋势,多变量检验能综合分析联合变量的变化趋势,单变量和多变量M-K趋势分析方法结合应用,能同时考虑整体序列中的每个成分的趋势变化,从而得出更加可靠和准确的结论,分析结果对进一步了解青海高原降水特征,合理开发和利用降水资源具有重要的参考价值。

基于RCC-M规范建造的核电站一回路水压试验工艺优化研究

就ASME和RCC-M两种体系标准关于压力试验的技术差异开展了溯源研究,结合断裂力学计算结果与压力爆破试验数据对水压试验的目的和能力进行了分析,通过论述超声技术的发展和研究一回路边界完整性,得出泄漏试验替代水压试验对一回路完整性不会带来负面影响的结论。

库兰粉在水钢265 m^(2)烧结机上的探索及应用

本文通过制定库兰粉不同配比用料结构方案,用烧结杯试验,烧结矿冶金性能低温还原粉化及软化熔滴性能实验,对其结果分析、比较,判定,并运用于工业生产实践,在目前烧结工艺、设备及高炉冶炼条件下,烧结用料结构中搭配配比7%的库兰粉是可行的。

移动学习的M-Test系统的设计与实现

近几年来,随着移动通信技术的蓬勃发展和移动通信设备的普及,移动学习应运而生。移动学习系统的研究与应用带给人们更加便利、更加积极、更加自主的学习环境。针对这种情况,提出了一种移动学习的做题测试系统(M-Test)及其设计与实现。在设计上,阐述了系统模型结构和数据设计,概述了系统的特点。在实现方面,介绍了移动测试流程和移动测试模块的开发与实现,包括开发的软件环境,界面设计以及开发中的主要技术实现。最后,说明了系统当前研究的价值和存在的不足。