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Project management maturity in construction consulting services: Case of Expo in China

Yongkui LI, Qing YANG, Yan ZHANG

《工程管理前沿(英文)》 2020年 第7卷 第3期   页码 384-395 doi: 10.1007/s42524-019-0070-z

摘要: For many years, project management maturity models (PMMM) derived from the software industry have brought immeasurable benefits. However, the adoption and investigation of PMMM in the construction field have been weak and insufficient, particularly in construction consulting services (CCS). Moreover, professionals have gradually realized the importance of non-process factors (e.g., teamwork, culture, leadership) in the evaluation of PMMM. This study describes the construction of PMMM for CCS that considers non-process factors and combines them with CCS-specific process factors. To verify the effectiveness of the proposed model, we conduct a case study on the overall project management consultancy for China’s 2010 Winter Expo. The results would fill in the PMMM research gap in CCS and provide practitioners with ideas to improve their performance.

关键词: construction consulting services     project management maturity model     non-process factors     Expo    

Influencing factors and control measures of excavation on adjacent bridge foundation based on analytichierarchy process and finite element method

Shuangxi FENG, Huayang LEI, Yongfeng WAN, Haiyan JIN, Jun HAN

《结构与土木工程前沿(英文)》 2021年 第15卷 第2期   页码 461-477 doi: 10.1007/s11709-021-0705-0

摘要: Many uncertain factors in the excavation process may lead to excessive lateral displacement or over-limited internal force of the piles, as well as inordinate settlement of soil surrounding the existing bridge foundation. Safety control is pivotal to ensuring the safety of adjacent structures. In this paper, an innovative method is proposed that combines an analytic hierarchy process (AHP) with a finite element method (FEM) to reveal the potential impact risk of uncertain factors on the surrounding environment. The AHP was adopted to determine key influencing factors based on the weight of each influencing factor. The FEM was used to quantify the impact of the key influencing factors on the surrounding environment. In terms of the AHP, the index system of uncertain factors was established based on an engineering investigation. A matrix comparing the lower index layer to the upper index layer, and the weight of each influencing factor, were calculated. It was found that the excavation depth and the distance between the foundation pit and the bridge foundation were fundamental factors. For the FEM, the FE baseline model was calibrated based on the case of no bridge surrounding the foundation pit. The consistency between the monitoring data and the numerical simulation data for a ground settlement was analyzed. FE simulations were then conducted to quantitatively analyze the degree of influence of the key influencing factors on the bridge foundation. Furthermore, the lateral displacement of the bridge pile foundation, the internal force of the piles, and the settlement of the soil surrounding the pile foundation were emphatically analyzed. The most hazardous construction condition was also determined. Finally, two safety control measures for increasing the numbers of support levels and the rooted depths of the enclosure structure were suggested. A novel method for combining AHP with FEM can be used to determine the key influencing aspects among many uncertain factors during a construction, which can provide some beneficial references for engineering design and construction.

关键词: deep foundation pit excavation     adjacent bridge foundation     influencing factors     analytic hierarchy process     finite element    

Generic and SME-specific factors that influence the BIM adoption process: an overview that highlights

Elodie HOCHSCHEID, Gilles HALIN

《工程管理前沿(英文)》 2020年 第7卷 第1期   页码 119-130 doi: 10.1007/s42524-019-0043-2

摘要: Building information modeling/management (BIM) is an emerging technological and procedural shift in the architecture, engineering, construction and operation industry. In this study, we use an extensive state-of-the-art method to clarify the BIM adoption process and the factors that can influence the success or failure of BIM adoption, particularly during the implementation stage, which are not frequently found in the literature. As an innovation, the lexical field allocated to the spread of innovations is assigned to BIM (diffusion, adoption, and implementation). After recalling the definition of relevant terms and then removing the resulting inconsistencies in vocabularies, we investigate various studies to identify factors that influence BIM adoption and then unify all these studies in one coherent and consistent BIM adoption process model. We focus on factors that play a role in the adoption of BIM in small- and medium-sized enterprises (SMEs) because SMEs constitute the majority of companies in the construction sector. This research highlights and intends to fill in some gaps found in the current BIM adoption literature.

关键词: BIM     adoption     diffusion     implementation     change management     SMEs     literature review     architecture firms    

Non-equilibrium model for catalytic distillation process

WANG Feng, ZHAO Ning, LI Junping, XIAO Fukui, WEI Wei, SUN Yuhan

《化学科学与工程前沿(英文)》 2008年 第2卷 第4期   页码 379-384 doi: 10.1007/s11705-008-0071-7

摘要: A new improved tri-diagonal method was developed for the non-equilibrium stage model of the catalytic distillation by coupling consumptive reaction coefficient. The reactions in the distillation column were divided into generative reaction and consumptive reaction. The non-equilibrium stage model was introduced for the catalytic distillation process of the dimethyl carbonate (DMC) synthesis by urea methanolysis over solid based catalyst, and the improved tri-diagonal method was used to solve the model equations. Comparison of predicted results with experiment data shows that the mean relative error of the yield of DMC was 3.78% under different conditions such as different operating pressures and reaction temperatures. The improved tri-diagonal matrix method could avoid the negative values of the liquid compositions during the calculations and restrain the fluctuation of compositions by slowing down the variations of the values in the iteration. The modeling results show that the improved tri-diagonal method was appropriate for system containing a wide range of boiling point components and a different rate of reactions.

Process analysis of syngas production by non-catalytic POX of oven gas

Fuchen WANG , Xinwen ZHOU , Wenyuan GUO , Zhenghua DAI , Xin GONG , Haifeng LIU , Zunhong YU ,

《能源前沿(英文)》 2009年 第3卷 第1期   页码 117-122 doi: 10.1007/s11708-008-0078-2

摘要: A non-catalytic POX of oven gas is proposed to solve the problem of secondary pollution due to solid wastes produced from the great amount of organic sulfur contained in oven gas in the traditional catalytic partial oxidation (POX) process. A study of the measurement of flow field and a thermodynamic analysis of the process characteristics were conducted. Results show that there exist a jet-flow region, a recirculation-flow region, a tube-flow region, and three corresponding reaction zones in the non-catalytic POX reformer. The combustion of oven gas occurs mainly in the jet-flow region, while the reformation of oven gas occurs mainly in the other two regions. Soot would not be formed by CH cracking at above 1200°C. Since there are very little C hydrocarbons in oven gas, the soot produced would be very tiny, even if they underwent cracking reaction. The integrated model for entrained bed gasification process was applied to simulate a non-catalytic POX reformer. It indicated that the proper oxygen-to-oven gas ratio is 0.22–0.28 at different pressures in the oven gas reformation process.

关键词: oven gas     non-catalytic POX process     syngas    

Progress on cleaner production of vinyl chloride monomers over non-mercury catalysts

Jinli ZHANG, Nan LIU, Wei LI, Bin DAI

《化学科学与工程前沿(英文)》 2011年 第5卷 第4期   页码 514-520 doi: 10.1007/s11705-011-1114-z

摘要: Polyvinyl chloride (PVC) has become the third most used plastic after polyethylene and polypropylene and the worldwide demand continues to increase. Polyvinyl chloride is produced by polymerization of the vinyl chloride monomer (VCM), which is manufactured industrially via the dehydrochlorination of dichloroethane or the hydrochlorination of acetylene. Currently PVC production through the acetylene hydrochlorination method accounts for about 70% of the total PVC production capacity in China. However, the industrial production of VCM utilizes a mercuric chloride catalyst to promote the reaction of acetylene and hydrogen chloride. During the hydrochlorination, the highly toxic mercuric chloride tends to sublime, resulting in the deactivation of the catalyst and also in severe environmental pollution problems. Hence, for China, it is necessary to explore environmental friendly non-mercury catalysts for acetylene hydrochlorination as well as high efficiency novel reactors, with the aim of sustainable PVC production via the acetylene-based method. This paper presents a review of non-mercury heterogeneous and homogeneous catalysts as well as reactor designs, and recommends future work for developing cleaner processes to produce VCM over non-mercury catalysts with high activity and long stability.

关键词: polyvinyl chloride     vinyl chloride monomer     acetylene hydrochlorination     non-mercury catalysts     green chemical process    

A family of non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems

Guizhong XIE, Fenglin ZHOU, Hao LI, Xiaoyu WEN, Fannian MENG

《机械工程前沿(英文)》 2019年 第14卷 第3期   页码 332-341 doi: 10.1007/s11465-019-0540-3

摘要: This study focuses on establishing non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems when the dual boundary element method is applied. The asymptotic behavior of the physical variables in the area near the crack front is fully considered in the construction of the shape function. In the developed quadrilateral and triangular crack front elements, the asymptotic term, which captures the asymptotic behavior of the physical variable, is multiplied directly by the conventional Lagrange shape function to form a new crack front shape function. Several benchmark numerical examples that consider penny-shaped cracks and straight-edge crack problems are presented to illustrate the validity and efficiency of the developed crack front elements.

关键词: Taylor expansion     crack front elements     stress intensity factors     dual boundary element method    

Non-toxic, high selectivity process for the extraction of precious metals from waste printed circuit

《环境科学与工程前沿(英文)》 2023年 第17卷 第10期 doi: 10.1007/s11783-023-1723-z

摘要:

● Au, Ag and Pd were recovered from WPCBs with high efficiencies.

关键词: Thiosulfate     Printed circuit boards     Precious metals     Leaching     Hydrometallurgy    

非线性计数系统的关键因子辨识方法 Research Article

张新民,王静波,魏驰航,宋执环

《信息与电子工程前沿(英文)》 2022年 第23卷 第1期   页码 123-133 doi: 10.1631/FITEE.2000324

摘要: 从数据中识别对系统输出产生较大影响的关键因子是科学和工程领域最具挑战性的任务之一。本文针对非线性计数系统,提出基于敏感性分析的广义高斯过程回归(SA-GGPR)建模方法,以识别影响系统输出的关键因子。SA-GGPR采用具有泊松似然的GGPR模型描述非线性计数系统。GGPR模型继承了非参数核学习和泊松分布的优点,可处理复杂非线性计数系统。然而,由于GGPR模型的非参数核学习架构,难以理解GGPR模型中输入和输出之间的关系。SA-GGPR方法通过定量评估不同输入对系统输出的影响来辨识影响系统输出的关键因子。在模拟非线性计数系统和实际钢铁轧制过程的应用结果表明,SA-GGPR方法在识别精度方面优于几种先进方法。

关键词: 关键因子;非线性计数系统;广义高斯过程回归;敏感性分析;钢铁轧制过程    

Process control factors for continuous microbial perchlorate reduction in the presence of zero-valent

ARTHUR Robert D.,TORLAPATI Jagadish,SHIN Kyung-Hee,CHA Daniel K.,YOON Yeomin,SON Ahjeong

《环境科学与工程前沿(英文)》 2014年 第8卷 第3期   页码 386-393 doi: 10.1007/s11783-013-0593-1

摘要: Process control parameters influencing microbial perchlorate reduction via a flow-through zero-valent iron (ZVI) column reactor were investigated in order to optimize perchlorate removal from water. Mixed perchlorate reducers were obtained from a wastewater treatment plant and inoculated into the reactor without further acclimation. Examined parameters included hydraulic residence time (HRT), pH, nutrients requirement, and perchlorate reduction kinetics. The minimum HRT for the system was concluded to be 8 hr. The removal efficiency of 10 mg·L influent perchlorate concentration was reduced by 20%–80% without control to the neutral pH (HRT= 8 hr). Therefore pH was determined to be an important parameter for microbial perchlorate reduction. Furthermore, a viable alternative to pH buffer was discussed. The microbial perchlorate reduction followed the first order kinetics, with a rate constant ( ) of 0.761 hr . The results from this study will contribute to the implementation of a safe, cost effective, and efficient system for perchlorate reduction to below regulated levels.

关键词: perchlorate     zero-valent iron (ZVI)     microbial reduction     hydrogen    

Capacity analysis for cognitive heterogeneous networks with ideal/non-ideal sensing

Tao HUANG, Ying-lei TENG, Meng-ting LIU, Jiang LIU

《信息与电子工程前沿(英文)》 2015年 第16卷 第1期   页码 1-11 doi: 10.1631/FITEE.1400129

摘要: Due to irregular deployment of small base stations (SBSs), the interference in cognitive heterogeneous networks (CHNs) becomes even more complex; in particular, the uncertainty of spectrum mobility aggravates the interference context. In this case, how to analyze system capacity to obtain a closed-form expression becomes a crucial problem. In this paper we employ stochastic methods to formulate the capacity of CHNs and achieve a closed-form expression. By using discrete-time Markov chains (DTMCs), the spectrum mobility with respect to the arrival and departure of macro base station (MBS) users is modeled. Then an integral method is proposed to derive the interference based on stochastic geometry (SG). Also, the effect of sensing accuracy on network capacity is discussed by concerning false-alarm and miss-detection events. Simulation results are illustrated to show that the proposed capacity analysis method for CHNs can approximate the conventional sum methods without rigorous requirement for channel station information (CSI). Therefore, it turns out to be a feasible and efficient way to capture the network capacity in CHNs.

关键词: Cognitive heterogeneous networks     Markov chain     Stochastic geometry     Homogeneous Poisson point process (HPPP)    

清洁高效的提取冶金——矿浆电解

邱定蕃

《中国工程科学》 1999年 第1卷 第1期   页码 67-72

摘要:

环境污染和能源短缺是重有色金属冶炼的两大障碍。在对重有色金属湿法冶金存在主要问题进行分析的基础上研究成功的矿浆电解新技术,是一种清洁、高效的提取冶金。它具有流程短、能耗低、金属分离好和环境污染少等特点。矿浆电解的显著特点是充分利用了电积过程的阳极反应来浸出矿石,工艺能耗大大降低;在电解槽中硫化物转化为元素硫,而不产生硫酸,有利于环境保护。文章描述了国内外矿浆电解技术的发展过程及我国建立的世界上第一个矿浆电解工业生产厂的概况,指出我国在该领域处于世界领先地位和矿浆电解技术具有很好的前景。

关键词: 重有色金属     湿法冶金     矿浆电解     提取冶金    

基于非易失存储器的版本化进程细粒度容错 None

Wen-zhe ZHANG, Kai LU, Xiao-ping WANG

《信息与电子工程前沿(英文)》 2018年 第19卷 第2期   页码 192-205 doi: 10.1631/FITEE.1601477

摘要: 提出一个基于NVRAM的新型容错进程模型——版本化进程(versionized process,VerP)。

关键词: 非易失存储器;字节粒度持久;版本化进程;版本号    

Investigation of Generalized SIFs of cracks in 3D piezoelectric media under various crack-face conditions

Jaroon RUNGAMORNRAT, Bounsana CHANSAVANG, Weeraporn PHONGTINNABOOT, Chung Nguyen VAN

《结构与土木工程前沿(英文)》 2020年 第14卷 第2期   页码 280-298 doi: 10.1007/s11709-019-0586-7

摘要: This paper investigates the influence of crack geometry, crack-face and loading conditions, and the permittivity of a medium inside the crack gap on intensity factors of planar and non-planar cracks in linear piezoelectric media. A weakly singular boundary integral equation method together with the near-front approximation is adopted to accurately determine the intensity factors. Obtained results indicate that the non-flat crack surface, the electric field, and the permittivity of a medium inside the crack gap play a crucial role on the behavior of intensity factors. The mode-I stress intensity factors ( ) for two representative non-planar cracks under different crack-face conditions are found significantly different and they possess both upper and lower bounds. In addition, for impermeable and semi-permeable non-planar cracks treated depends strongly on the electric field whereas those of impermeable, permeable, and semi-permeable penny-shaped cracks are identical and independent of the electric field. The stress/electric intensity factors predicted by permeable and energetically consistent models are, respectively, independent of and dependent on the electric field for the penny-shaped crack and the two representative non-planar cracks. Also, the permittivity of a medium inside the crack gap strongly affects the intensity factors for all crack configurations considered except for of the semi-permeable penny-shaped crack.

关键词: crack-face conditions     intensity factors     non-flat cracks     permittivity     piezoelectric media     SGBEM    

Meta-analysis of the risk factors of breast cancer concerning reproductive factors and oral contraceptive

Qiong DAI MD, Bei LIU MD, Yukai DU MM,

《医学前沿(英文)》 2009年 第3卷 第4期   页码 452-458 doi: 10.1007/s11684-009-0080-z

摘要: The authors performed a meta-analysis of case-control studies that addressed whether reproductive factors and oral contraceptive use were associated with breast cancer by searching the MEDLINE, PubMed, Proquest, Embase, ScienceDirect, African Healthline, BMJ Health Intelligence and Chinese Periodical net databases for all English-language and Chinese-language papers published from January 1, 1997 to December 31, 2007. A total of 15 studies calculating pool ORs indicated that menopausal age >50yr [odds ratio (OR), 1.39; 95% confidence interval (CI), 1.22―1.57] and oral contraceptive use (OR, 2.12*, “*”: summary OR was adjusted; 95% CI, 1.24―3.62) were correlated with the increase in breast cancer risk while the summary OR based on number of full-term pregnancies ≥1 (OR, 0.63*; 95% CI, 0.60―0.68) and breast-feeding (OR, 0.76; 95% CI, 0.64―0.90) indicated no association with breast cancer risk. The correlation was statistically significant. Menopausal age >50yr and oral contraceptive use are positively correlated with an increase in breast cancer risk while breast-feeding and number of full-term pregnancies ≥1 are protective factors.

关键词: meta-analysis     breast cancer     risk factors     reproductive factors     oral contraceptive use    

标题 作者 时间 类型 操作

Project management maturity in construction consulting services: Case of Expo in China

Yongkui LI, Qing YANG, Yan ZHANG

期刊论文

Influencing factors and control measures of excavation on adjacent bridge foundation based on analytichierarchy process and finite element method

Shuangxi FENG, Huayang LEI, Yongfeng WAN, Haiyan JIN, Jun HAN

期刊论文

Generic and SME-specific factors that influence the BIM adoption process: an overview that highlights

Elodie HOCHSCHEID, Gilles HALIN

期刊论文

Non-equilibrium model for catalytic distillation process

WANG Feng, ZHAO Ning, LI Junping, XIAO Fukui, WEI Wei, SUN Yuhan

期刊论文

Process analysis of syngas production by non-catalytic POX of oven gas

Fuchen WANG , Xinwen ZHOU , Wenyuan GUO , Zhenghua DAI , Xin GONG , Haifeng LIU , Zunhong YU ,

期刊论文

Progress on cleaner production of vinyl chloride monomers over non-mercury catalysts

Jinli ZHANG, Nan LIU, Wei LI, Bin DAI

期刊论文

A family of non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems

Guizhong XIE, Fenglin ZHOU, Hao LI, Xiaoyu WEN, Fannian MENG

期刊论文

Non-toxic, high selectivity process for the extraction of precious metals from waste printed circuit

期刊论文

非线性计数系统的关键因子辨识方法

张新民,王静波,魏驰航,宋执环

期刊论文

Process control factors for continuous microbial perchlorate reduction in the presence of zero-valent

ARTHUR Robert D.,TORLAPATI Jagadish,SHIN Kyung-Hee,CHA Daniel K.,YOON Yeomin,SON Ahjeong

期刊论文

Capacity analysis for cognitive heterogeneous networks with ideal/non-ideal sensing

Tao HUANG, Ying-lei TENG, Meng-ting LIU, Jiang LIU

期刊论文

清洁高效的提取冶金——矿浆电解

邱定蕃

期刊论文

基于非易失存储器的版本化进程细粒度容错

Wen-zhe ZHANG, Kai LU, Xiao-ping WANG

期刊论文

Investigation of Generalized SIFs of cracks in 3D piezoelectric media under various crack-face conditions

Jaroon RUNGAMORNRAT, Bounsana CHANSAVANG, Weeraporn PHONGTINNABOOT, Chung Nguyen VAN

期刊论文

Meta-analysis of the risk factors of breast cancer concerning reproductive factors and oral contraceptive

Qiong DAI MD, Bei LIU MD, Yukai DU MM,

期刊论文