Optimal intervention strategies for multiple objects affected by manifest and latent deterioration processes

In the existing infrastructure management systems, optimal interventions strategies (OISs) are determined for objects that deteriorate gradually (manifest deterioration process, MDPs), under the assumption that with appropriate inspection and intervention strategies the probability of failure of object can be neglected. Objects that deteriorate suddenly (latent deterioration process, LDPs), for example, due to scouring during a flood or earth movements during an earthquake are not considered. The determination of OISs for an object that deteriorates due to both MDPs and LDPs requires the consideration of both. The latter, however, means that the probability of failure of the object must be considered. In this article, a Markov model is presented that can be used to determine OISs for multiple objects of multiple types affected by uncorrelated MDPs and LDPs. The model is an extension of the model proposed by Mayet and Madanat (Incorporation of seismic considerations in bridge management systems. Computer-Aided Civil and Infrastructure Engineering, 17:185–193, 2002). In the model, a set of condition states (CSs) is used to describe the condition of objects of each type, where each set is composed of non-failure CSs and failure CSs. The probabilities of going from each non-failure CS to each failure CS are estimated using normalised fragility curves, and the probabilities of going from each non-failure CS to each non-failure CS are initially estimated using the Markov deterioration prediction model of Kobayashi, Kaito, and Lethanh (A Bayesian estimation method to improve deterioration prediction for infrastructure system with Markov chain model. International Journal of Architecture, Engineering and Construction, 1:1–13, 2012a) and later adjusted taking into consideration the probabilities of entering the failure CSs. The use of the model is demonstrated using a road link comprising one road section and one bridge.     

Copper accumulation in soils from two different‐aged apricot orchards in Central Otago,New Zealand

In recent years there has been a move in New Zealand to convert small, uneconomic orchards to other agricultural uses. Overseas research has demonstrated that copper from fungicide sprays often accumulates in the soils of orchards and can cause certain problems for plant growth and livestock. To date, no assessments appear to have been made of the degree of copper accumulation in such older orchards in New Zealand. This study presents the results of an assessment of two well‐established apricot orchards in the Central Otago region of South Island, New Zealand.

Two aspects of the results are surprising. The first is the relatively low levels of copper in the soil when compared with results from another orchard in the region. That orchard is 18 years old and mean soil copper has already reached 100.0 μg/g, indicating a much faster rate of accumulation than in the two orchards in the current study. The second unexpected result is that the younger orchard has a significantly higher level of copper than the older orchard. Reasons for these findings are discussed in relation to apparent differences in soil properties.     

良山铁矿提升交通安全管理水平的途径

交通安全工作直接关系到职工的生命和企业财产安全,关系到企业的稳定和经济建设的发展。本文探讨了抓好交通车辆管理的途径,并对筑牢交通安全堤防展开探讨。     

钢结构工程设计质量问题的分析

随着我国钢材制造工艺水平达到了新的阶段,钢结构材料在建筑工程设计中也成为了主要考虑对象。由于钢结构建筑设计难度大,且对建筑物图纸方案要求严格,因此必须注重钢结构建筑设计质量的综合管理。     

基于精益建造的铁路施工项目管理研究

本文引入精益建造思想,将其充分应用至铁路施工项目管理的质量、成本和进度这三个主要的方面,并对项目管理目标实行了动态管理,从而有效实现了资源的优化配置,降低了项目成本,提高了铁路施工企业经济效益。     

建筑电气工程的施工质量管理分析

在建筑电气工程施工中对其质量进行管理和控制,既可以有效提高建筑电气工程施工质量,同时对提高建筑物的整体使用性能和舒适度有着重要意义。本文就当前建筑电气工程施工质量管理中存在的问题及弊端进行了分析,并提出了相应的解决对策。     

试论现代工程项目管理工作策略

本文主要从工程项目管理特点入手分析,阐述项目管理目标建立,以及保质完成管理目标应采取的一些措施和手段。经验浅薄,仅供同行参考。     

建筑管理方法探索

在全球经济逐步迈向一体化的进程中,中国建筑市场也正经受着来自世界经济环境的巨大挑战。文章立足于当前建筑施工企业在常规业务经营与创新、企业监督与管理等,提出了一系列的改进方法与措施方案。     

工程成本控制管理与实战

本文对建筑工程企业施工阶段的成本进行了详细地探析,并提出了加强工程成本管理与控制的一些策略,以期能给相关工作人员一些建议。     

如何做好工程施工质检资料管理

工程施工资料是工程在施工过程中,将其中一些有价值的声像、图表、图纸、文字等事物保存起来的记录。即时、准确、完善、有效的质检资料是工程检测的保障,所以工程施工过程中的质量保证,就必须要有一系列完整的质检资料的管理措施。