软粘土地基沉降计算问题研究

建筑基础修筑在软粘土地基上,必然引起地基内应力,使地基变形从而使建筑下沉。建筑的沉降以及同一建筑不同部位的差异沉降的计算,是岩土工程的重要课题。本文分析了软粘土地基沉降的分析计算问题。     

浅论汽轮发电机的运行故障

汽轮发电机是进行能源转化的一种关键设备,其以电磁感应定律及电磁力定律为基础,能将其他形式的能源转化为电能,当汽轮发电机出现运行故障时,会极大地影响发电效率.论文在阐述汽轮发电机运行原理的基础上,就其常见的故障类型展开分析,同时针对性地指出汽轮发电机运行故障处理对策.期望能进一步提升汽轮发电机运行的稳定性和安全性,满足电...     

汽轮发电机断股故障情况下电磁场和温度场的计算与分析

本文就主要依据实例对汽轮发电机断股故障情况下的电磁场和温度场进行了计算和分析.采用构建模型和有限元法来对电磁场和温度场的参数进行合理的计算,通过对前后断股的情况进行分析,可以了解到交直轴的变化具体情况,将电磁分析作为计算的基础,对热源的分布情况进行合理的探究,从而得出断股故障出现后,会对电机的温度以及位置产生怎样的影响.希望本文的探究能够为相关的人员提供一定的参考.     

大型汽轮发电机故障特征规律的研究

本文主要研究讨论大型汽轮发电机故障的特征及规律,主要的故障分为静子故障、转子故障、轴承故障、轴瓦故障及机座外壳故障几种,对于这几种故障进行特征及诊断分析,通过利用对子系统液压进行润滑及冷却参数来对大型汽轮发电机组的故障进行诊断,主要的目标就是为了对发电机的故障进行准确的判断,并及时进行故障排除。这样不但可以降低由于发电机故障而引起的经济损失,同时还可以降低事故的发生机率,保证人们生命安全。     

汽轮发电机氢气排污方法的安全性及经济性分析

汽轮发电机氢气排污方法最经常使用的有两种,一种是连续式补氢排污的方式,另一种是间断式补氢排污的方式,这两种方式各有各的优势,具体选择哪一种更加具有安全性以及经济性,则需要与依据实际情况而定,但是大体上讲,连续式补氢方式优势更加突出,本文通过某公司实践案列的介绍,对汽轮发电机氢气排污方法的安全性及经济性进行了分析,希望有所帮助。     

浅析建筑地基不均匀沉降问题的防治措施

随着社会的发展和经济的进步促使我国加快了城镇化建设的脚步。城镇化的推进自然离不开建筑行业的支持,随着我国建筑业的快速发展,高楼大厦的不断建成,许多建筑类的问题也在不断的凸显出来,这些问题不断地困扰着整个建筑行业,也影响到了建筑行业的建筑效率和建筑质量,同时使得许多建筑公司的信誉受到了影响。建筑类的问题有许多种类,从设计到施工再到验收不同的时间段内存在着不同的问题,但建筑地基问题则是其中最重要的问题之一,并且地基问题直接涉及到了整个建筑的安全性不得不格外重视。本文简要分析了建筑地基不均匀沉降的危害及产生原因,并提出了相应的防治措施。     

柔性基础下复合地基的工作性状

柔性基础下的复合地基理论相对复杂,在实践应用中的经常出现较大的工程浪费和不安全性,通过对复合地基的加固作用分析,介绍柔性基础下复合地基的作用机理和桩土应力比的影响因素,在考虑土拱效应的前提下计算桩土应力比和沉降量,充分了解柔性基础下复合地基的相互作用特征,以对工程理论和实践起到指导作用。     

不同场地条件下基础施工的地基检验重点

作为建筑类工程的重要组成部分,地基基础工程的质量直接与建筑物的结构安全产生直接影响,并关系到人民的生命财产安全。在目前工程施工的要求下,建筑工程嵌挤基础工作则是工程勘察,并发挥着极为重要的作用。本文主要从不同产地条件下基础施工的地基检验重要进行了详细分析。     

农业院校大学计算机基础课程分层教学模式的研究

文章通过教学实践发现现有的教学模式存在一系列的问题,通过对问题的分析提出了分层教学模式。根据农业院校的大学计算机基础课的教学现状,笔者对计算机基础课程的教学目标、教学内容、教学模式等进行了研究,为了提高教学质量和教学效果,结合农业院校的现实情况制订了改革的方案。     

Sensitivity analysis and application to trotting of a noninvasive method to calculate flexor tendon forces in the equine forelimb

OBJECTIVE: To test the sensitivity to measurement and modeling errors of a method for noninvasive calculation of flexor tendon forces in the equine forelimb and to calculate tendon forces for Dutch Warmblood horses during trotting. SAMPLE POPULATION: A normative set of kinematic and ground-reaction force (GRF) data obtained from horses during trotting in another study. PROCEDURE: Forces in the flexor tendons were calculated from the data set before and after addition of fixed relative and absolute errors. Amount of error was based on normal accuracy of the variables. A similar analysis was performed for a measure of strain of the accessory ligament of the deep digital flexor tendon. RESULTS: The only errors that had a substantial influence on accuracy were modeling errors in the mechanical properties of the suspensory ligament and measurement errors in the point of application of the GRF and position of the marker on the distal interphalangeal joint. Influence of the measurement errors could be minimized by applying usual correction methods. CONCLUSIONS AND CLINICAL RELEVANCE: After correction of measurement errors, the method can be used to calculate mean tendon forces for a group of horses and to evaluate the influence of factors such as surface properties, type of shoe, speed, and fatigue on tendon forces. The method could become an important tool for use in research on the cause, prevention, and treatment of tendon injuries in horses.     

Model formulation and determination of in vitro parameters of a noninvasive method to calculate flexor tendon forces in the equine forelimb

OBJECTIVE: To describe a method to calculate flexor tendon forces on the basis of inverse dynamic analysis and an in vitro model of the equine forelimb and to quantify parameters for the model. SAMPLE POPULATION: 38 forelimbs of 23 horses that each had an estimated body mass of > or = 500 kg. PROCEDURE: Longitudinal limb sections were used to determine the lines of action of the tendons. Additionally, limb and tendon loading experiments were performed to determine mechanical properties of the flexor tendons. RESULTS: The study quantified the parameters for a pulley model to describe the lines of action. Furthermore, relationships between force and strain of the flexor tendons and between fetlock joint angle and suspensory ligament strain were determined, and the ultimate strength of the tendons was measured. CONCLUSION AND CLINICAL RELEVANCE: The model enables noninvasive determination of forces in the suspensory ligament, superficial digital flexor tendon, and distal part of the deep digital flexor (DDF) tendon. In addition, it provides a noninvasive measure of loading of the accessory ligament of the DDF tendon for within-subject comparisons. However, before application, the method should be validated. The model could become an important tool for use in research of the cause, prevention, and treatment of tendon injuries in horses.     

探讨深基坑基础防止钢筋笼柔性“S”变形的方法

在榆横~潍坊1000千伏特高压交流输变电工程线路工程基础施工中,深基坑基础钢筋绑扎安装是一个难点,由于深基坑基础具有方量大、孔径大、基坑深等特点,决定了在钢筋绑扎安装时无法按照普通基础的方法进行绑扎,容易产生钢筋笼整体柔性S变形扭曲。为解决1000k V特高压线路工程深基坑基础钢筋笼整体柔性S变形扭曲现象,拟在深基坑基础钢筋绑扎安装中采用将主筋吊起悬空绑扎和在坑壁设置控制点的施工工艺,可以有效的解决深基坑基础钢筋笼整体柔性S变形扭曲难点。     

Manacher算法在计算最长回文子串长度中的应用

本文首介绍了如何运用Manacher算法在线性时间内找到一个字符串的最长回文子串。     

Impact of different approaches to calculate the economics of disease in pig farming

Diagrams for analyzing the economics of sow and fattening farms are described and discussed. The diagrams are used to quantify the economic significance of a change in technical results for pig farms in the Netherlands. Sensitivity analyses show the importance of taking into account feed savings of piglets and sows due to, for instance, less litters per sow per year. To see whether there was an effect of the economic environment and the structure of the fanning system, the same calculations were carried out for Minnesota (USA). The economic effect of a change in results (e.g. days open) was smaller for Minnesota, but economic effects were similarly influenced by specific factors, such as feed intake and price. Subsequently, several scientific publications on the estimation of the costs of Aujeszky's disease in pigs were compared with respect to the economic methods used and the outcomes obtained. Because of different estimation procedures, the costs of the disease varied significantly. Differences are mainly due to the loss items that were taken into account, the way the loss items were calculated and the structure of the farming system that was included. There is a need for a standardized framework of how to conduct a sound economic evaluation, in order to make the outcome of different calculations more comparable and interpretable.     

Reanalysis of the start of the UK 1967 to 1968 foot-and-mouth disease epidemic to calculate airborne transmission probabilities

The aims of this study were to statistically reassess the likelihood that windborne spread of foot-and-mouth disease (FMD) virus (FMDV) occurred at the start of the UK 1967 to 1968 FMD epidemic at Oswestry, Shropshire, and to derive dose-response probability of infection curves for farms exposed to airborne FMDV. To enable this, data on all farms present in 1967 in the parishes near Oswestry were assembled. Cases were infected premises whose date of appearance of first clinical signs was within 14 days of the depopulation of the index farm. Logistic regression was used to evaluate the association between infection status and distance and direction from the index farm. The UK Met Office's NAME atmospheric dispersion model (ADM) was used to generate plumes for each day that FMDV was excreted from the index farm based on actual historical weather records from October 1967. Daily airborne FMDV exposure rates for all farms in the study area were calculated using a geographical information system. Probit analyses were used to calculate dose-response probability of infection curves to FMDV, using relative exposure rates on case and control farms. Both the logistic regression and probit analyses gave strong statistical support to the hypothesis that airborne spread occurred. There was some evidence that incubation period was inversely proportional to the exposure rate.     

Comparison of different methods to calculate venous admixture in anaesthetized horses

Objective

The aim of this study was to compare different methods to determine venous admixture (${\dot{Q}}_{\text{s}}/{\dot{Q}}_{\text{t}}$) in anaesthetized horses. The first objective was to estimate ${\dot{Q}}_{\text{s}}/{\dot{Q}}_{\text{t}}$ using jugular venous blood oxygen content (${\dot{Q}}_{\text{s}}/{\dot{Q}}_{\text{t}\text{jugular}}$), and a fixed value for the oxygen extraction (F-shunt). The second objective was to assess the influence of blood pressure and positioning on oxygen extraction. The third objective was to perform regression analysis between jugular and mixed venous blood oxygen tensions.

饲料安全的影响因素及解决对策

随着经济全球化的加快和我国加入WTO ,以及我国人民生活水平的提高和全面进入小康社会 ,人们对食品、畜产品的安全、品质的要求越来越高。要获得高质量的畜产品 ,首先应该有高质量的饲料 ,于是在国家政策的引导下 ,饲料界和养殖界专家学者、企业家、养殖户都在寻求从安全饲料到健康养殖的高效、可持续发展途径。本文主要介绍了影响饲料安全的因素及解决对策。1　饲料安全的定义饲料安全是指饲料产品必须对动物健康和正常生长、生态环境的可持续发展、人类健康和生活不会产生不良影响。能否保证饲料安全涉及饲料原料的来源、生产加工、贮存…