资源类型

期刊论文 9

年份

2022 1

2019 1

2017 1

2015 1

2012 1

2009 1

2008 1

2007 2

展开 ︾

关键词

大掺量矿物掺合料高性能混凝土 1

矿物掺合料 1

质量控制 1

配制与施工 1

展开 ︾

检索范围：

排序： 展示方式：

Construction engineering management culture shift: Is the lowest tender offer dead?

Eric SCHEEPBOUWER, Douglas D. GRANSBERG, Carla Lopez del PUERTO

《工程管理前沿（英文）》 2017年 第4卷 第1期   页码 49-57 doi: 10.15302/J-FEM-2017014

摘要： The procurement of public construction projects must walk a fine line between the corruption of state officials and collusion of contractors. The method of awarding projects to the lowest responsible tenderer was originally implemented to guard against corruption of state officials. However, an investigation of the construction industry in the Canadian province of Quebec showed that lowest-tender-offer procurement gave rise to collusion of companies tendering for the contracts. Alternatively, best-value procurement has been used for decades, but here problems arise owing to the necessity of subjective judging of measures other than price to compare bids, giving rise to time- and money-consuming protests. The paper proposes a compelling argument that the construction engineering management (CEM) culture should refocus its efforts on enhancing project cost certainty rather than merely searching for means to design a project in a manner that produces the lowest initial cost, and awards the construction to the lowest tender offer that focuses on cost savings during the project development and delivery process. The difference in the two approaches is subtle but extremely important. To make the transition, the engineering management tools must be advanced to the next level. This means that all project control tools for managing cost, schedule, and technical scope must be transformed from working in the deterministic mode to the stochastic mode, thus making the probability of completing the project within or below its official budget the primary decision criterion. To do so, CEMs must accept that there is a benefit in paying more for an alternative that increases cost certainty for the entire project. The authors of this paper hope that it will provide the grist for a more general dialog across all industry sectors where engineering management is practiced.

关键词： cost certainty     lowest responsible bid     best value     public procurement     construction engineering management culture    

HTML PDF 收藏

Lean Product Development—Faster, Better … Cleaner?

Geert Letens

《工程管理前沿（英文）》 2015年 第2卷 第1期   页码 52-59 doi: 10.15302/J-FEM-2015007

摘要： To address this challenge, lean product development has emerged to become the leading improvement methodology for companies toward the creation of a competitive advantage on innovation and technology leadership. While lean product development has its origin in the best practice studies of Japanese car manufacturers such as Toyota, it has been further elaborated in defence and aerospace organizations over the last two decades, and recently empirical evidence has become available for successful introductions in sectors different from the traditionally-studied environments. The primary purpose of this work is to untangle the fuzziness that still surrounds lean product development and to ground the key aspects of lean product development based on insights from six studies published in a special issue of the on this topic. This demonstrates how better and faster product development can be achieved through the integration of lean principles with the best of more traditional new product development (NPD) practices, into a holistic system that can be characterised by value-focused and risk-based decision making, the socio-technical integration of people and process, improved project, pipeline and portfolio management, optimized knowledge management, and the creation of a learning organization. Unfortunately, while the increasing global competition offers the potential to improve the quality of life for many, the spirit of faster, better, and cheaper also threatens to endanger the future of our planet as a whole. As the majority of a product’s social and ecological impacts are committed in the design phase, it, therefore, seems imperative to investigate the integration of lean product development and eco-design principles. As a result, this work also explores the symbiosis of both approaches through the identification of tools and methods that can support the triple bottom-line goals for a sustainable future of life and business.

关键词： lean product development     sustainability engineering     responsible design    

HTML PDF 收藏

Not asthma, but GERD: case report

WANG Zhonggao

《医学前沿（英文）》 2007年 第1卷 第1期   页码 115-119 doi: 10.1007/s11684-007-0022-6

摘要： Asthma is a disorder of the lungs characterized by increased responsiveness of the airways, as manifested by episodes of wheezing and increased resistance to expiratory airflow because of varying degrees of smooth muscle contraction, edema of the mucosa, and mucus in the lumen of the bronchi and bronchioles. The stimuli vary widely and include antigens, infection, air pollutants, respiratory tract irritants, exercise, and emotional factors. This condition is completely different from distress breathing because of laryngotracheal spasm. One of its causes is the gastric content reflux through the pharynx to the larynx because of gastroesophageal reflux disease (GERD), in addition to the typical human avian flu that may cause immediate suffocation by laryngospasm owing to acute larygotrachitis. A patient suffered from GERD without esophageal symptoms, which was diagnosed and treated as bronchial asthma during his five emergency admissions. The admissions were because of episodic attacks of severe air hunger owing to an extreme throat tightening. The patient was being treated for as long as two years. After the correct diagnosis was made and treatment of laporascopic fundaplication was performed, the longstanding bronchial asthma , after all, completely disappeared. The concept of not asthma, but GERD seems undervalued, unappreciated, even misunderstood among patients with intractable asthma. Therefore, such a case is reported in detail, similar cases are mentioned briefly as well, and a mechanism responsible for GERD-originated larryngo- or laryngotracho-spasm is proposed.

关键词： resistance     mechanism responsible     unappreciated     responsiveness     different    

HTML PDF 收藏

Tender evaluation through efficiency analysis for public construction contracts

Stefan NIEWERTH, Peter VOGT, Markus THEWES

《工程管理前沿（英文）》 2022年 第9卷 第1期   页码 148-158 doi: 10.1007/s42524-020-0119-z

摘要： Given the European Public Procurement Directive 2014/24/EU, policymakers have ordered the inclusion of various criteria, such as the price, life-cycle costs, environmental, and social aspects, in the evaluation of tenders for public construction projects. Consequently, the relevance of non-monetary award criteria has gained significant value. However, the established evaluation formulas, which are used to obtain the best value for money procurement, have resulted in legal disputes. The existing evaluation formulas exhibit mathematical weaknesses, wherein scoring indices do not express economic efficiency adequately. Thus, a conflict is observed between the political requirement of non-monetary award criteria and their evaluation by contracting authorities. To overcome such dilemma, an extensive literature review is conducted. Specifically, this study explores the essential problems of existing evaluation formulas and develops a more reliable method. The technique from the field of efficiency analysis, i.e., Data Envelopment Analysis (DEA), is adopted in this study. For contract awarding, the DEA is extended by introducing a decision theoretical framework. For public procurement, the proposed method combines two advantages. First, the proposed method ensures the derivation of a robust tender ranking given that with respect to clients’ preferences, irrelevant and insufficiently tailored tenders do not influence the scoring. Second, the proposed method supports the intention of policy makers to promote public goals, such as sustainable aspects. By disclosing the strengths and weaknesses of bidders with respect to their competitors, all bidders can obtain a precise overview of their performance regarding the award criteria. In sum, the proposed method allows a targeted improvement of certain criteria values in future tenders and consequently leads to an enhancement of public goals.

关键词： bid evaluation     public procurement     best value for money     data envelopment analysis     contractor selection    

HTML PDF 收藏

Nano thermo-hydrodynamics method for investigating cell membrane fluidity

YANG Yang, LIU Jing

《能源前沿（英文）》 2008年 第2卷 第2期   页码 121-128 doi: 10.1007/s11708-008-0033-2

摘要： As a barrier to compartmentalize cells, membranes form the interface between a cell and its surroundings. The essential function of a membrane is to maintain a relatively stable environment in the cell, exchange substances selectively and transfer energy and information continually from the outside. It is intriguing that above the phase transition temperature, the membrane lipid molecule will have three modes–lateral diffusion, rotational movement and flip-flop activity. These thermodynamic processes are vital to cell existence, growth, division, differentiation and are also responsible for hundreds of thousands of phenomena in life. Previously, species transport across the membrane was interpreted mainly from a phenomenological view using a lumped system model. Therefore, detailed flow processes occurred in the membrane domain and clues related to life mechanism were not sufficiently tackled. Such important issues can be clarified by modeling nano scale thermal hydrodynamics over the gap space of a cell membrane. Previously observed complex membrane behaviors will be shown in this paper and explained by the thermally induced fluidic convections inside the membrane. A correlation between nano scale hydrodynamics, non-equilibrium thermodynamics and cell membrane activities is set up. The disclosed mechanisms are expected to provide a new viewpoint on the interaction between intracellular and extracellular processes through the membrane.

关键词： responsible     phenomenological     phenomena     modes–lateral diffusion     differentiation    

HTML PDF 收藏

Relationship between expression of hepatocyte grow factor and apoptosis of trophoblasts in hypertensive disorder complicating pregnancy

OUYANG Shan, ZHANG Qinghua, QIAO Fuyuan

《医学前沿（英文）》 2007年 第1卷 第4期   页码 386-389 doi: 10.1007/s11684-007-0075-6

摘要： The aim of this study was to investigate the expression of hepatocyte growth factor (HGF) and Fas in placentas of uncomplicated pregnant women and those with hypertensive disorder complicating pregnancy (HDCP), and elucidate the possible relationship between HGF and apoptosis of trophoblasts. Reverse transcription-polymerase chain reaction (RT-PCR) was undertaken to examine the concentration of HGF mRNA and Fas mRNA obtained from 34 cases of HDCP and 30 cases of uncomplicated pregnancy. The expression of HGF mRNA in mild preeclampsia, severe preeclampsia and eclampsia cases was significantly lower than that in the uncomplicated cases (0.43±0.12, 0.38±0.09, 0.19±0.17 versus 0.67±0.19, <0.05), while the expression of Fas mRNA in mild preeclampsia, severe preeclampsia and eclampisa cases was significantly higher than that in the uncomplicated cases (1.58±0.26, 2.96±0.14, 5.98±1.17 versus 1.01±0.36, <0.05). For HGF mRNA and Fas mRNA, there was no difference between gestational hypertension cases and control cases. Decreased HGF mRNA or increased Fas mRNA was found along with the progress of HDCP. Negative correlation was found between the expressions of HGF and Fas. These results indicate that HGF inhibits the apoptosis mediated by Fas, and the reduced expression of HGF in HDCP may be responsible for the apoptosis of trophoblasts.

关键词： pregnancy     concentration     possible relationship     responsible     hepatocyte    

HTML PDF 收藏

Demand response based congestion management in a mix of pool and bilateral electricity market model

Ashwani KUMAR, Charan SEKHAR

《能源前沿（英文）》 2012年 第6卷 第2期   页码 164-178 doi: 10.1007/s11708-012-0187-9

摘要： The independent system operator (ISO) is a key element in the deregulated structure with one of the responsibilities of transmission congestion management (CM). The ISO opts market based solutions to manage congestion receiving bids from generation companies (GENCOs) as well as distribution companies (DISCOMs) to reschedule their generation and relocate demand. The nodal prices increases during the congestion hours and the demand response to nodal prices will be an effective tool for the control of congestion. In this paper, demand response-based CM has been proposed for a mix of pool and bilateral electricity market model. The linear bid curves have been considered for demand bids to respond to the congestion in the network. The bilateral demand has been obtained with minimum deviations in their preferred schedule. The impact of flexible alternating current transmission system (FACTS) devices viz static var compensator (SVC) and thyristor controlled series compensator (TCSC) has also been considered for demand management during congestion. Multi-line congestion cases have been considered to study the impact on demand response without and with FACTS devices. The proposed approach has been tested on the IEEE 24 bus test system.

关键词： bid function     congestion management (CM)     demand response     pool+bilateral electricity market     static var compensator (SVC)     thyristor controlled series compensator (TCSC)    

HTML PDF 收藏

大掺量矿物掺合料高性能混凝土在京沪高铁四标段中的应用

高治双,赵年全,赵常煜,胡明文,苟云龙

《中国工程科学》 2009年 第11卷 第1期   页码 26-31

摘要：

以京沪高速铁路为工程背景，试验研究了矿物掺合料（粉煤灰、粉煤灰-矿粉）对混凝土工作性能、力学性能和耐久性能的影响以及大掺量矿物掺合料高性能混凝土的配制技术。结合实际工程，介绍了大掺量矿物掺合料高性能混凝土原材料选择、配合比设计、施工工艺等方面的控制技术。

关键词： 矿物掺合料     大掺量矿物掺合料高性能混凝土     配制与施工     质量控制    

HTML PDF 收藏

A comparative review of the state and advancement of Site-Specific Crop Management in the UK and China

Zhenhong LI, James TAYLOR, Lynn FREWER, Chunjiang ZHAO, Guijun YANG, Zhenhai LI, Zhigang LIU, Rachel GAULTON, Daniel WICKS, Hugh MORTIMER, Xiao CHENG, Chaoqing YU, Zhanyi SUN

《农业科学与工程前沿（英文）》 2019年 第6卷 第2期   页码 116-136 doi: 10.15302/J-FASE-2018240

摘要：

Precision agriculture, and more specifically Site-Specific Crop Management (SSCM), has been implemented in some form across nearly all agricultural production systems over the past 25 years. Adoption has been greatest in developed agricultural countries. In this review article, the current situation of SSCM adoption and application is investigated from the perspective of a developed (UK) and developing (China) agricultural economy. The current state-of-the art is reviewed with an emphasis on developments in position system technology and satellite-based remote sensing. This is augmented with observations on the differences between the use of SSCM technologies and methodologies in the UK and China and discussion of the opportunities for (and limitations to) increasing SSCM adoption in developing agricultural economies. A particular emphasis is given to the role of socio-demographic factors and the application of responsible research and innovation (RRI) in translating agri-technologies into China and other developing agricultural economies. Several key research and development areas are identified that need to be addressed to facilitate the delivery of SSCM as a holistic service into areas with low precision (PA) agriculture adoption. This has implications for developed as well as developing agricultural economies.

关键词： remote sensing     decision support     responsible research and innovation     digital soil mapping    

HTML PDF 收藏

标题 作者 时间 类型 操作

Construction engineering management culture shift: Is the lowest tender offer dead?

Eric SCHEEPBOUWER, Douglas D. GRANSBERG, Carla Lopez del PUERTO

期刊论文

Lean Product Development—Faster, Better … Cleaner?

Geert Letens

期刊论文

Not asthma, but GERD: case report

WANG Zhonggao

期刊论文

Tender evaluation through efficiency analysis for public construction contracts

Stefan NIEWERTH, Peter VOGT, Markus THEWES

期刊论文

Nano thermo-hydrodynamics method for investigating cell membrane fluidity

YANG Yang, LIU Jing

期刊论文

Relationship between expression of hepatocyte grow factor and apoptosis of trophoblasts in hypertensive disorder complicating pregnancy

OUYANG Shan, ZHANG Qinghua, QIAO Fuyuan

期刊论文

Demand response based congestion management in a mix of pool and bilateral electricity market model

Ashwani KUMAR, Charan SEKHAR

期刊论文

大掺量矿物掺合料高性能混凝土在京沪高铁四标段中的应用

高治双,赵年全,赵常煜,胡明文,苟云龙

期刊论文

A comparative review of the state and advancement of Site-Specific Crop Management in the UK and China

Zhenhong LI, James TAYLOR, Lynn FREWER, Chunjiang ZHAO, Guijun YANG, Zhenhai LI, Zhigang LIU, Rachel GAULTON, Daniel WICKS, Hugh MORTIMER, Xiao CHENG, Chaoqing YU, Zhanyi SUN

期刊论文