高层建筑燃气管道设计的探讨

本文针对高层建筑管道燃气设计中的一些问题,结合管道燃气的供气特点进行分析和探讨,并对高层建筑管道燃气设计的理论进行总结.     

浅谈市政道路施工中管道燃气网的布设

本文主要就市政道路施工中管道燃气网布设的方式、施工管道燃气网的布设工艺、施工中管道燃气网在布设时容易出现的问题及解决措施进行介绍.     

某电雷管的可靠性评估

火工品的可靠性直接关系到使用系统性能的正确发挥和人员安全,因此,火工品的可靠性工作贯穿于设计、研制、生产、贮存、使用和管理的全过程.本文采用某电雷管设计定型鉴定批数据对研制阶段的可靠性进行了评估,为使用该电雷管提供可靠性数据.     

连续退火炉双燃料在线混烧技术

介绍宁波宝新不锈钢公司的焦炉煤气和天然气两种燃气同时在线混烧退火炉,分析不锈钢连续退火炉同时使用两种燃气、分区切换和混合燃烧的设备原理和操作经验.双燃料烧嘴是不停机快速切换燃气的基础,两套独立的燃气管道连接到双燃料烧嘴,随时根据需要通过烧嘴前阀门实现燃气快速切换.为确保两种燃气有效安全隔离,设计了氮气自动吹扫和控制保护.控制软件中采用两套控制参数,每个燃烧控制区都能够根据燃气种类自动选择正确的控制参数.     

高层建筑燃气管道设计中的若干问题

介绍了根据《高层民用建筑设计防火规范》、《城市燃气设计规范》等的规定，在城市高层建筑燃气管道设计中的系统压力、引入管、楼内供气管道系统敷设形式、用气安全设施等方面的设计经验。     

基于IAHP-靶心贴近度法的充填管道可靠性评估

为对充填管道可靠性进行科学评估,建立了基于改进层次分析法(IAHP)、靶心贴近度法的综合评估模型。以湖南某矿山为研究对象,选取了充填料浆骨料体积分数等10个指标构建了综合评价指标体系,采用改进层次分析法确定指标权重,通过计算评估对象各等级单指标区间函数和综合贴近度,基于最大隶属度原则,对矿山充填管道可靠性进行风险等级评估,并与未确知测度理论和云模型评估结果进行对比。结果表明,基于IAHP-靶心贴近度法的充填管道可靠性综合评估模型结果合理,具有计算简便、直观可靠、操作性强等优势,为充填管道可靠性评估提供了新思路。     

高层民用建筑室内燃气设计有关问题的分析及措施

随着城市建设的迅速发展 ,各种高层民用建筑日益增多 ,而高层建筑的特点不同于多层建筑。在实际的室内燃气设计中 ,如果对有些问题考虑欠妥或措施不当 ,将给燃气设施的安全使用带来一系列问题 ,甚至会引发事故。因此 ,对高层民用建筑室内燃气设计要非常慎重 ,并尽可能采取适当的处理措施 ,以保证燃气设施的安全运行。本文作者仅就高层民用建筑在室内燃气设计中所遇到的问题加以分析与探讨。1　高层建筑对燃气引入管的影响分析及处理措施由于防冻等原因 ,在设计室内燃气管道时 ,燃气引入管一般选择埋地引入。高层建筑由于建筑高、自重大 ,本…     

燃气管道入城市综合管廊的危险有害因素辨析

新型市政基础设施——综合管廊,使管线"统一建设、统一规划、统一管理"不再是口号,管线直埋带来的很多难题都被解决,是市政管线建设的趋势和方向。燃气管道入综合管廊具有火灾、爆炸、中毒、窒息等危险性,稍有不慎可能发生燃爆事故。通过分析燃气管道入城市综合管廊可能存在的危险有害因素,提出相应的安全对策措施。     

燃气-蒸汽联合循环发电工程并网运行方式研究

具体分析比较了济钢燃气-蒸汽联合循环发电工程三种典型并网运行方式的功率损耗、运行安全可靠性、工程投资等主要技术经济性能。     

管制员可靠性的分析

本文主要针对空中交通管制工作的过程及特点,提出了管制员可靠性的定义,同时对影响管制员可靠性的一系列因素进行分析,在一定程度上为提高管制员工作的可靠性提供一些建议.     

Reliability of precision alloys

The ability of precision alloys to perform faultlessly in electronics, aviation, and elsewhere, in the presence of external interference, is considered. Means of improving the reliability of precision alloys in challenging operating conditions are formulated.     

过盈联结的可靠性设计

根据可靠性设计理论，推导出了过盈联结强度的可靠性设计和计算的通用公式．对有可靠性要求、大尺寸及一些重要的过盈联结建立了可行的设计方法，为提高联结的强度和可靠性提供了有效途径．     

Reliability of absence measures.

4 different absence measures were defined and examined: attitudinal absences, absence frequency, absence severity, and medical absences. Attitudinal absences and absence frequency were sufficiently reliable to be used as criterion measures; absence severity and medical absences were considered to be too unreliable for use as criterion measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reliability Analysis of Plank Decks

The objective of this study is to summarize the load and resistance criteria for highway bridge plank decks, and to estimate the reliability of plank decks designed by the AASHTO Code. Both transverse and longitudinal planks for a variety of typical stringer spacings and plank sizes are considered. Truck traffic load data are based on the model used to calibrate the 1994 AASHTO LRFD Code. However, for plank decks, wheel load rather than whole vehicle weight is most important, and these statistics are developed for this study. For wood planks, dead load and dynamic load are not significant. The limit state considered is flexural strength, and resistance statistics are presented for wood planks in terms of modulus of rupture. Special flat-wise use data are presented to account for section aspect ratio as well as edge of load application. The reliability analysis is carried out using the procedure developed for calibration of AASHTO LRFD. Reliability indices for both the AASHTO Standard and AASHTO LRFD Code are presented for plank decks. The results indicate that there are considerable differences in plank reliability indices. Causes of inconsistencies in safety are identified.     

Reliability of skin biopsy pathology

BACKGROUND: The diagnosis of skin disease by histologic examination is regarded as the reference standard upon which therapy and follow-up are determined. Our study investigated the reliability of skin biopsy diagnosis requested by family physicians and physicians' assistants. METHODS: Biopsy diagnoses by a community-based pathology group were reinterpreted by our study dermatopathologist on a sample of 119 skin biopsies randomly selected from the 1844 biopsies performed by family physicians and physicians' assistants at a large Washington State health maintenance organization during a 4 1/2-year period. RESULTS: There were 107 exact matches and 3 mismatches of premalignant lesions and 6 mismatches of benign diagnoses. In addition, two melanomas diagnosed by the community-based pathologists were interpreted as benign by our study dermatopathologist. A third melanoma diagnosed by the community-based group was interpreted as a poorly differentiated squamous cell cancer by the university dermatopathologist. The weighted kappa, 0.83, indicated excellent interrater agreement. CONCLUSION: Although our study showed excellent interrater concordance of skin biopsy interpretation, there was disagreement about three melanomas between a community-based general pathology group and our study dermatopathologist. The melanoma disagreement is consistent with previous studies that found poor interrater agreement for early melanomas. The community-based pathologists were uncertain about two of these melanomas, and as part of their quality control and review procedures requested confirmation by an expert pathologist, who agreed with the melanoma diagnosis. Family physicians are justified in requesting a second opinion (if not automatically requested by a community laboratory) when the histopathologic diagnosis is not in concordance with the clinical history or impression or when the pathologist is unsure of the diagnosis.     

Reliability Evaluation of Earth Slopes

The reliability analysis of earth slopes is considered. For slope safety assessment, the first-order reliability method is employed for estimating the probability of failure or reliability index. Since the failure of any slip surfaces implies failure of the slope, the slope is considered as a series system. The system aspect of the slope in the reliability analysis is dealt with by defining a limit state of the system as a function of the minimum of the ratio of the shear strength to the mobilized shear strength for each of all potential slip surfaces. Such a ratio for a given slip surface is evaluated using the extended generalized method of slices. The reliability analysis procedure described is applied to example slopes to illustrate the impact of the probability distribution type, and the spatial variability of the soil properties on the probability of failure of the slopes.     

Reliability of drug dependents'' self-reports

An increasing number of sphingolipids, glycosphingolipids and some of their degradation products have been recognized in recent years as second messengers involved in signal transduction and as modulators of numerous cellular functions. These can be converted into inert, caged compounds, introduced into cells and tissues and subsequently photolysed to active compounds thus enabling the study of fast biological processes. The novel, potentially caged compounds synthesized here are substituted 2-nitrobenzyl urethans and 2-nitrobenzyl amines derived from sphingosine, dihydrosphingosine, N-methylsphingosine, N-methyldihydrosphingosine, psychosine and glucosylsphingosine. Upon irradiation of the afore mentioned compounds they release, or are expected to release, the free biologically active amines.     

Reliability Analysis of Earth Dams

In the present study, results of reliability analyses of four selected rehabilitated earth dam sections, i.e., Chang, Tapar, Rudramata, and Kaswati, under pseudostatic loading conditions, are presented. Using the response surface methodology, in combination with first order reliability method and numerical analysis, the reliability index (β) values are obtained and results are interpreted in conjunction with conventional factor of safety values. The influence of considering variability in the input soil shear strength parameters, horizontal seismic coefficient (αh), and location of reservoir full level on the stability assessment of the earth dam sections is discussed in the probabilistic framework. A comparison of results with those obtained from other method of reliability analysis, viz., Monte Carlo simulations combined with limit equilibrium approach, provided a basis for discussing the stability of earth dams in probabilistic terms, and the results of the analysis suggest that the considered earth dam sections are reliable and are expected to perform satisfactorily.     

可靠性在设备维修中的应用

介绍了可靠性预测方法、故障统计理论的基本概念。并通过实例分析阐述了可靠性维修的应用方法。