Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 4

年份

2023 1

2019 1

2009 1

关键词

个体抗缺氧能力 1

影响因素 1

青藏铁路 1

非参数检验 1

高原反应 1

展开︾

检索范围：

排序：展示方式：

Key uncertainty events impacting on the completion time of highway construction projects

Alireza MOGHAYEDI, Abimbola WINDAPO

《工程管理前沿（英文）》 2019年第6卷第2期页码 275-298 doi: 10.1007/s42524-019-0022-7

摘要： This paper examines the uncertainty events encountered in the process of constructing highways, and evaluates their impact on construction time, on highway projects in South Africa. The rationale for this examination stems from the view held by scholars that the construction of highways is a complex process, taking place in changing environments and often beset by uncertainties; and that there is a lack of appropriate evaluation of these uncertainty events occurring during the construction process. The research made use of a review of extant literature in the area of uncertainty management, and modeling in infrastructure projects, to guide the direction of the study. The inquiry process consisted of brainstorming by highway experts and interviewing them to identify the uncertainty factors that impact construction time. An uncertainty matrix for South African highway projects was developed, using a quantitative model and descriptive statistics. It emerged from the study that the uncertainty events affecting the construction time of highway projects are distributed across economic, environmental, financial, legal, political, social and technical factors. Also, it was found that each factor might account for several uncertainty events which impact on construction time differently, through a combination of the uncertainty events of the individual construction activities. Based on the obtained data, an Adaptive Neuro Fuzzy Inference System (ANFIS) has been developed, as a simple, reliable and accurate advanced machine learning technique to assess the impact of uncertainty events on the completion time of highway construction projects. To validate the ANFIS model, the Stepwise Regression (SR) models have been designed and their results are compared with the results of the ANFIS. Based on the predicted impact size of uncertainty events on the time of highway projects, it can be concluded that construction time on South African highway projects is significantly related to the social and technical uncertainties factors.

关键词： ANFIS construction time impact assessment highway project South Africa uncertainty

HTML PDF 收藏

Recent advances in electrochemical decontamination of perfluorinated compounds from water: a review

《环境科学与工程前沿（英文）》 2023年第17卷第2期 doi: 10.1007/s11783-023-1618-z

摘要：

● Recent advances in the electrochemical decontamination of PFAS are reviewed.

关键词： Perfluorinated compounds Electrochemical approach Working mechanisms Impacting factor Coupled process

HTML PDF 收藏

Numerical studies of dynamic behavior of liquid film on single-layer wire mesh with different wettabilities

《化学科学与工程前沿（英文）》页码 1672-1680 doi: 10.1007/s11705-022-2205-8

摘要： Droplet impacting on the stainless steel wire mesh is very common in chemical devices, like a rotating packed bed. Surface wettability of wire mesh significantly affects the liquid flow pattern and liquid dispersion performance. However, the effect of surface wettability on the impaction phenomena at microscale such as liquid film is still unknown. In this work, the dynamic behavior of liquid film on the surface of wire mesh was analyzed by computational fluid dynamics simulation. The dynamic behavior of liquid film on the surface of wire mesh can be divided into the following three steps: (1) spreading step; (2) shrinkage process; (3) stabilizing or disappearing step. Effects of surface wettability, as well as operating conditions, on wetting area and liquid film thickness were studied. Compared to the hydrophilic wire mesh, the final wetting area of hydrophobic wire mesh is zero in most cases. The average liquid film thickness on the surface of hydrophilic wire mesh is 30.02–77.29 μm, and that of hydrophobic wire mesh is 41.76–237.37 μm. This work provided a basic understanding of liquid film flow at microscale on the surface with various surface wettabilities, which can be guiding the packing optimization and design.

关键词： stainless steel wire mesh computational fluid dynamics surface wettability liquid film impacting

HTML PDF 收藏

基于非参数检验的高原反应影响因素分析

常海娟,刘猛,庞丽萍,杨鹏 ,王浚

《中国工程科学》 2009年第11卷第2期页码 65-69

摘要：

用一年的时间随青藏铁路列车采集了2 882样本数据，随机抽取其中的1 693份，利用非参数检验及相关分析的方法从统计学上对可能影响耐缺氧反应的因素做分析，最后发现以前到高原时缺氧反应严重程度、性别、吸烟习惯、肥胖度、年龄５个因素对个体的抗缺氧能力有着不可忽视的影响。该结论不仅可以为减少旅客高原反应提供指导性意见，为高原旅客列车供氧系统设计和改进提供重要依据，也可以为后续的医学研究提供统计学基础。

关键词：高原反应影响因素青藏铁路非参数检验个体抗缺氧能力