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Performance of seven highway construction contracting methods analyzed by project size

Yuanxin ZHANG, Abdol CHINI, R. Edward MINCHIN Jr., Lourdes PTSCHELINZEW, Dev SHAH

《工程管理前沿（英文）》 2018年 第5卷 第2期   页码 240-250 doi: 10.15302/J-FEM-2018040

摘要： The conventional Design-Bid-Build (DBB) construction contracting method has had various drawbacks exposed in highway construction practice, including lack of communication, inefficient design, antagonizing relationships, and increased disputes. To mitigate the negative aspects of DBB, several alternative contracting methods and alternative project delivery systems have been devised and introduced to the industry over the past 30 years. Five such innovations were tested by a research team from the University of Florida under the sponsorship of the Florida Department of Transportation (FDOT). To perform a realistic assessment, this study categorized FDOT projects built between 2006 and 2015 into groups according to current contract amounts. Both absolute and relative metrics were defined and employed. For comparison purposes, a collective analysis on all gathered data was performed. Additionally, the influence of outliers on the results was examined. The results showed that analyses based on individual cost categories are more convincing because large projects tend to impose stronger influence on the analyses. In addition, outliers must be identified and screened to reach realistic and reliable conclusions. With regard to the actual performance of the contracting methods, each performs differently within different cost categories.

关键词： alternative contracting methods     time     cost     performance evaluation    

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Study on System Coupling Interaction of Large-Scale Construction Companies Programme Contracting and

Feng Guo,Tian Huang

《工程管理前沿（英文）》 2015年 第2卷 第2期   页码 137-140 doi: 10.15302/J-FEM-2015022

摘要： Constant changes in the construction market have resulted in individual projects being challenged to meet the long-term growth needs of large construction companies. Change should be based on the construction of this new model project group, to achieve better interaction, and to allow for a more rapid enterprise development. This paper is based on the system coupling analysis of large-scale construction enterprises and construction projects. A clear system presents itself and forms the basis of the system construction, institutional change and mechanism of the path between base construction projects and business growth.

关键词： programme contracting     firm growth     coupling interaction     system     large construction companies    

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Are Relational Contracting Approaches Applicable to Public Projects in China?

Wei-ya Hao,Hui-ping Ding,Yong-jian Ke,Ying-ying Wang

《工程管理前沿（英文）》 2014年 第1卷 第4期   页码 358-363 doi: 10.15302/J-FEM-2014052

摘要： Rising complexities in construction projects management has boosted the importance of relational contracting (RC) in the field. RC is based on recognition of mutual benefits and win-win scenarios gained through more cooperative relationships between contracting parties. There have been a range of RC initiatives across many countries towards deeper collaborative relationships; however, such formal RC approaches are not yet well established in China. In this paper, the feasibility of implementing RC in the China’s public construction projects is investigated. The results indicate that RC is highly feasible for implementation in China due to its theoretical benefits, its alignment to Chinese culture, and its behaviors in past public construction projects. Three strategies for facilitating the implementation of RC in China are proposed.

关键词： relational contracting     public construction     relationship    

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生物燃料替代石油——产业现状与可持续发展

李十中

《中国工程科学》 2011年 第13卷 第2期   页码 50-56

摘要：

文章分析了用生物燃料替代石油以实现控制全球气候变化、减少石油消耗和环境污染、创造就业机会，实现社会经济的可持续发展的重要性；介绍了国内外生物燃料产业发展历程和趋势，以及在汽车燃料和航空燃料领域的应用现状，提出了我国当前发展生物燃料的战略和对策。

关键词： 生物燃料     替代石油     交通     发展    

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Evaluation of the contract reliability for alternative infrastructure project delivery: a contract engineering

Bing WANG, Qingbin CUI, Shuibo ZHANG

《工程管理前沿（英文）》 2019年 第6卷 第2期   页码 239-248 doi: 10.1007/s42524-019-0018-3

摘要： Governments at all levels are increasingly motivating the private sector to participate in infrastructure development using alternative project delivery methods to relieve financial burden. When designing contracts, governments usually offer incentives while requiring cost or time guarantee to balance project attractiveness to the private sector and fair protection of public interest. However, a practical and critical problem is how to properly design these provisions. Although previous studies have investigated the value of these provisions, a knowledge gap still exists with respect to methods of fairly and effectively designing such provisions. This study fills this gap by developing a methodology that analyzes the appropriateness of guarantee or warranty provisions for contracts. In this study, a contract reliability index is constructed, and a process of evaluating contract reliability is proposed. The New Mexico Highway 44 project, in which three warranty provision arrangements are investigated, is used as a case study to illustrate the analysis process. Results show that although a ceiling clause can effectively motivate the private sector to participate in the project, it sacrifices a significant amount of public benefits. By contrast, although a warranty option can protect public benefits, it cannot effectively incentivize the private sector. A combination of the ceiling clause and the warranty option will therefore result in improved contract provision design. The proposed methodology in this study is especially useful for governments in properly determining contract clauses in infrastructure development.

关键词： infrastructure development     contract design     contract reliability     guarantee provision     contract engineering    

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A naive optimization method for multi-line systems with alternative machines

Weichang KONG, Fei QIAO, Qidi WU

《机械工程前沿（英文）》 2019年 第14卷 第4期   页码 377-392 doi: 10.1007/s11465-019-0544-z

摘要： The scheduling of parallel machines and the optimization of multi-line systems are two hotspots in the field of complex manufacturing systems. When the two problems are considered simultaneously, the resulting problem is much more complex than either of them. Obtaining sufficient training data for conventional data-based optimization approaches is difficult because of the high diversity of system structures. Consequently, optimization of multi-line systems with alternative machines requires a simple mechanism and must be minimally dependent on historical data. To define a general multi-line system with alternative machines, this study introduces the capability vector and matrix and the distribution vector and matrix. A naive optimization method is proposed in accordance with classic feedback control theory, and its key approaches are introduced. When a reasonable target value is provided, the proposed method can realize closed-loop optimization to the selected objective performance. Case studies are performed on a real 5/6-inch semiconductor wafer manufacturing facility and a simulated multi-line system constructed on the basis of the MiniFAB model. Results show that the proposed method can effectively and efficiently optimize various objective performance. The method demonstrates a potential for utilization in multi-objective optimization.

关键词： multi-line systems     alternative machines     feedback control     closed-loop optimization    

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High frequency of alternative splicing variants of the oncogene in neuroendocrine tumors of the pancreas

《医学前沿（英文）》   页码 907-923 doi: 10.1007/s11684-023-1009-7

摘要： The characteristic genetic abnormality of neuroendocrine neoplasms (NENs), a heterogeneous group of tumors found in various organs, remains to be identified. Here, based on the analysis of the splicing variants of an oncogene Focal Adhesion Kinase (FAK) in The Cancer Genome Atlas datasets that contain 9193 patients of 33 cancer subtypes, we found that Box 6/Box 7-containing FAK variants (FAK6/7) were observed in 7 (87.5%) of 8 pancreatic neuroendocrine carcinomas and 20 (11.76%) of 170 pancreatic ductal adenocarcinomas (PDACs). We tested FAK variants in 157 tumor samples collected from Chinese patients with pancreatic tumors, and found that FAK6/7 was positive in 34 (75.6%) of 45 pancreatic NENs, 19 (47.5%) of 40 pancreatic solid pseudopapillary neoplasms, and 2 (2.9%) of 69 PDACs. We further tested FAK splicing variants in breast neuroendocrine carcinoma (BrNECs), and found that FAK6/7 was positive in 14 (93.3%) of 15 BrNECs but 0 in 23 non-NEC breast cancers. We explored the underlying mechanisms and found that a splicing factor serine/arginine repetitive matrix protein 4 (SRRM4) was overexpressed in FAK6/7-positive pancreatic tumors and breast tumors, which promoted the formation of FAK6/7 in cells. These results suggested that FAK6/7 could be a biomarker of NENs and represent a potential therapeutic target for these orphan diseases.

关键词： FAK6/7     SRRM4     neuroendocrine neoplasms     pancreas     breast    

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AGRI-ENVIRONMENTAL ASSESSMENT OF CONVENTIONAL AND ALTERNATIVE BIOENERGY CROPPING SYSTEMS PROMOTING BIOMASS

《农业科学与工程前沿（英文）》 2022年 第9卷 第2期   页码 284-294 doi: 10.15302/J-FASE-2021435

摘要：

Bioenergy, currently the largest renewable energy source in the EU (64% of the total renewable energy consumption), has sparked great interest to meet the 32% renewable resources for the 2030 bioeconomy goal. The design of innovative cropping systems informed by bioeconomy imperatives requires the evaluate of the effects of introducing crops for bioenergy into conventional crop rotations. This study aimed to assess the impacts of changes in conventional cropping systems in mixed dairy cattle farms redesigned to introduce bioenergy crops either by increasing the biomass production through an increase of cover crops, while keeping main feed/food crops, or by substituting food crops with an increase of the crop rotation length. The assessment is based on the comparison between conventional and innovative systems oriented to feed and biogas production, with and without tillage, to evaluate their agri-environmental performances (biomass production, nitrogen fertilization autonomy, greenhouse gas emissions and biogas production). The result showed higher values in the biogas cropping system than in the conventional and feed ones for all indicators, biomass productivity (27% and 20% higher, respectively), nitrogen fertilization autonomy (26% and 73% higher, respectively), methanogenic potential (77% and 41% higher, respectively) and greenhouse gas emissions (15% and 3% higher, respectively). There were no negative impacts of no-till compared to the tillage practice, for all tested variables. The biogas cropping system showed a better potential in terms of agri-environmental performance, although its greenhouse gas emissions were higher. Consequently, it would be appropriate to undertake a multicriteria assessment integrating agri-environmental, economic and social performances.

关键词： alternative cropping systems / bioeconomy / biogas / biomass production / fertilization autonomy / greenhouse gas assessment    

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Alternative energy development strategies for China towards 2030

Linwei MA , Zheng LI , Feng FU , Weidou NI , Xiliang ZHANG ,

《能源前沿（英文）》 2009年 第3卷 第1期   页码 2-10 doi: 10.1007/s11708-009-0014-0

摘要： The purposes, objectives and technology pathways for alternative energy development are discussed with the aim of reaching sustainable energy development in China. Special attention has been paid to alternative power and alternative vehicle fuels. Instead of limiting alternative energy to energy sources such as nuclear and renewable energy, the scope of discussion is extended to alternative technologies such as coal power with carbon capture and sequestration (CCS), electric and hydrogen vehicles. In order to take account of the fact that China’s sustainable energy development involves many dimensions, a six-dimensional indicator set has been established and applied with the aim of comprehensively evaluating different technology pathways in a uniform way. The analysis reaches the following conclusions: (a) in the power sector, wind power, nuclear power and hydro power should be developed as much as possible, while R&D of solar power and coal power with CCS should be strengthened continuously for future deployment. (b) in the transportation sector, there is no foreseeable silver bullet to replace oil on a large scale within the time frame of 20 to 30 years. To ease the severe energy security situation, expedient choices like coal derived fuels could be developed. However, its scale should be optimized in accordance to the trade-off of energy security benefits, production costs and environmental costs. Desirable alternative fuels (or technologies) like 2nd generation biofuels and electrical vehicles should be the subject of intensive R&D with the objective to be cost effective as early as possible.

关键词： alternative energy     China energy     technology pathway     six-dimensional evaluation    

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Experimental study of pollution effect on the behavior of high voltage insulators under alternative current

Hani BENGUESMIA, Nassima M’ZIOU, Ahmed BOUBAKEUR

《能源前沿（英文）》 2021年 第15卷 第1期   页码 213-221 doi: 10.1007/s11708-017-0479-1

摘要： In this paper, the impact of the conductivity and the distribution of pollution on the behavior of the high voltage insulator cap and pin 1512L, artificially polluted is described. An experimental model in form of a disc is proposed. This experimental model reproduces the real model which is the 1512L insulator. Besides, a comparative study is presented. For this comparative study, different solutions are adopted to s`imulate the pollution (containing NaCl+ distilled water) that has different conductivities for a discontinuous distribution of the pollution on the insulator under an AC voltage. Furthermore, the influence of the pollution on the flashover voltage and the leakage current is studied. Finally, the behavior of real and experimental model of the insulator is investigated.

关键词： 1512L insulator     circular model     artificial pollution     flashover     leakage current     discontinuous pollution     high voltage    

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Dimethyl ether as alternative fuel for CI engine and vehicle

Zhen HUANG , Xinqi QIAO , Wugao ZHANG , Junhua WU , Junjun ZHANG ,

《能源前沿（英文）》 2009年 第3卷 第1期   页码 99-108 doi: 10.1007/s11708-009-0013-1

摘要： As a developing and the most populous country in the world, China faces major challenges in energy supply and environmental protection. It is of great importance to develop clean and alternative fuels for internal combustion engines. On the basis of researches on DME engine and vehicle at Shanghai Jiaotong University in the last twelve years, fuel injection, combustion, performance and exhaust emissions of DME engine and DME vehicle are introduced in this paper. The results indicate that DME engines can achieve high thermal efficiency and ultra low emissions, and will play a significant role in meeting the energy demand while minimizing environmental impact in China.

关键词： dimethyl ether (DME)     fuel injection     combustion process     emission control     CI engine     vehicle    

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Life cycle analysis and choice of natural gas-based automotive alternative fuels in Chongqing Municipality

WU Rui, LI Guangyi, ZHANG Zongyi, REN Yulong, HAN Weijian

《环境科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 292-298 doi: 10.1007/s11783-007-0049-6

摘要： Road transport produces significant amounts of emissions by using crude oil as the primary energy source. A reduction of emissions can be achieved by implementing alternative fuel chains. The objective of this study is to carry out an economic, environmental and energy (EEE) life cycle study on natural gas-based automotive fuels with conventional gasoline in an abundant region of China. A set of indices of four fuels/vehicle systems on the basis of life cycle are assessed in terms of impact of EEE, in which natural gas produces compressed natural gas (CNG), methanol, dimethylether (DME) and Fischer Tropsch diesel (FTD). The study included fuel production, vehicle production, vehicle operation, infrastructure and vehicle end of life as a system for each fuel/vehicle system. A generic gasoline fueled car is used as a baseline. Data have been reviewed and modified based on the best knowledge available to Chongqing local sources. Results indicated that when we could not change electric and hydrogen fuel cell vehicles into commercial vehicles on a large scale, direct use of CNG in a dedicated or bi-fuel vehicle is an economical choice for the region which is most energy efficient and more environmental friendly. The study can be used to support decisions on how natural gas resources can best be utilized as a fuel/energy resource for automobiles, and what issues need to be resolved in Chongqing. The models and approaches for this study can be applied to other regions of China as long as all the assumptions are well defined and modified to find a substitute automotive energy source and establish an energy policy in a specific region.

关键词： dedicated     primary     economic     alternative     abundant    

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Assessment of an alternative to deep foundations in compressible clays: the structural cell foundation

Sergio A. MARTÍNEZ-GALVÁN, Miguel P. ROMO

《结构与土木工程前沿（英文）》 2018年 第12卷 第1期   页码 67-80 doi: 10.1007/s11709-017-0399-5

摘要： The new type of deep foundation for buildings on saturated, compressible-low strength clayey soil deposits, branded structural cell essentially consists of a rigid concrete top slab, structurally connected to reinforced concrete peripheral walls (diaphragms) that enclose the natural soil. Accordingly, as the initial volume of the confined soft clays within the lateral stiff diaphragms will remain constant upon loading, the hollowed structural cell will be “transformed” into a very large cross-section pillar of unit weight slightly higher than that of the natural soft clayey soil. This type of foundation seems to be a highly competitive alternative to the friction pile-box foundations (widely used in Mexico City clays), due to its economic and environmental advantages. Economies result, for example, from the absence of huge excavations hence sparing the need of earth retaining structures. Further savings result from appreciably smaller concrete volumes required for building the structural cell than the friction pile-box foundation; moreover, the construction time of the former is much shorter than that of the latter. Regarding the impact to the environment, less air contamination follows from the fact that both traffic jams and soil excavation lessen appreciably. Considering these facts and others regarding scheduling, it was decided to replace 48-friction pile-box foundations specified in the master plan project by this new type of foundation. The overall behavior of these cell foundations over a five-year period is fared from close visual observations and their leveling during the first three years after their construction.

关键词： deep foundations     bearing capacity     resistant moment     structural cell     3D numerical modeling    

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Alternative splicing of inner-ear-expressed genes

null

《医学前沿（英文）》 2016年 第10卷 第3期   页码 250-257 doi: 10.1007/s11684-016-0454-y

摘要：

Alternative splicing plays a fundamental role in the development and physiological function of the inner ear. Inner-ear-specific gene splicing is necessary to establish the identity and maintain the function of the inner ear. For example, exon 68 of Cadherin 23 (Cdh23) gene is subject to inner-ear-specific alternative splicing, and as a result, Cdh23(+68) is only expressed in inner ear hair cells. Alternative splicing along the tonotopic axis of the cochlea contributes to frequency tuning, particularly in lower vertebrates, such as chickens and turtles. Differential splicing of Kcnma1, which encodes for the α subunit of the Ca2+-activated K+ channel (BK channel), has been suggested to affect the channel gating properties and is important for frequency tuning. Consequently, deficits in alternative splicing have been shown to cause hearing loss, as we can observe in Bronx Waltzer (bv) mice and Sfswap mutant mice. Despite the advances in this field, the regulation of alternative splicing in the inner ear remains elusive. Further investigation is also needed to clarify the mechanism of hearing loss caused by alternative splicing deficits.

关键词： alternative splicing     inner ear     hearing loss     hair cells    

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Confined masonry as practical seismic construction alternative–the experience from the 2014 Cephalonia

Fillitsa KARANTONI, Stavroula PANTAZOPOULOU, Athanasios GANAS

《结构与土木工程前沿（英文）》 2018年 第12卷 第3期   页码 270-290 doi: 10.1007/s11709-017-0390-1

摘要：

During August 1953 three strong earthquakes of magnitude ranging from 6.3 to 7.2 shook the Ionian Island of Cephalonia (Kefalonia), Greece, and destroyed almost the entire building stock of the Island which consisted primarily of traditional unreinforced masonry (URM) houses. The authorities went on to restructuring of the building stock, using a structural system that is most like what is known today as confined masonry. They designed about 14 types of one- to two-storey buildings providing the engineers with detailed construction plans. These buildings are known as “Arogi” buildings (Arogi in Greek meaning Aid). On the 24th of January and 3rd of February 2014, two earthquakes of magnitude 6.1 and 6.0 struck the island, causing significant soil damages, developing excessively high ground accelerations. Surprisingly, no damage was reported in the “Arogi” buildings. The seismic behavior of the buildings is examined by FEM linear analysis and it is compared to that of URM structures. Computed results illustrate that the displacements of identical URM buildings would be about twice the magnitudes observed in the corresponding “Arogi” ones, with the implication that the earthquake sequence of 2014 would have caused critical damage should the type of structure be of the URM type. Furthermore, it is illustrated that this low cost alternative method of construction is a very effective means of producing earthquake resilient structures, whereas further reduction of seismic displacement may be achieved in the order of 50% with commensurate effects on damage potential, when reinforced slabs are used to replace the timber roofs.

关键词： Cephalonia     confined masonry     comparative FEM analysis     unreinforced masonry     seismic damage    

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标题 作者 时间 类型 操作

Performance of seven highway construction contracting methods analyzed by project size

Yuanxin ZHANG, Abdol CHINI, R. Edward MINCHIN Jr., Lourdes PTSCHELINZEW, Dev SHAH

期刊论文

Study on System Coupling Interaction of Large-Scale Construction Companies Programme Contracting and

Feng Guo,Tian Huang

期刊论文

Are Relational Contracting Approaches Applicable to Public Projects in China?

Wei-ya Hao,Hui-ping Ding,Yong-jian Ke,Ying-ying Wang

期刊论文

生物燃料替代石油——产业现状与可持续发展

李十中

期刊论文

Evaluation of the contract reliability for alternative infrastructure project delivery: a contract engineering

Bing WANG, Qingbin CUI, Shuibo ZHANG

期刊论文

A naive optimization method for multi-line systems with alternative machines

Weichang KONG, Fei QIAO, Qidi WU

期刊论文

High frequency of alternative splicing variants of the oncogene in neuroendocrine tumors of the pancreas

期刊论文

AGRI-ENVIRONMENTAL ASSESSMENT OF CONVENTIONAL AND ALTERNATIVE BIOENERGY CROPPING SYSTEMS PROMOTING BIOMASS

期刊论文

Alternative energy development strategies for China towards 2030

Linwei MA , Zheng LI , Feng FU , Weidou NI , Xiliang ZHANG ,

期刊论文

Experimental study of pollution effect on the behavior of high voltage insulators under alternative current

Hani BENGUESMIA, Nassima M’ZIOU, Ahmed BOUBAKEUR

期刊论文

Dimethyl ether as alternative fuel for CI engine and vehicle

Zhen HUANG , Xinqi QIAO , Wugao ZHANG , Junhua WU , Junjun ZHANG ,

期刊论文

Life cycle analysis and choice of natural gas-based automotive alternative fuels in Chongqing Municipality

WU Rui, LI Guangyi, ZHANG Zongyi, REN Yulong, HAN Weijian

期刊论文

Assessment of an alternative to deep foundations in compressible clays: the structural cell foundation

Sergio A. MARTÍNEZ-GALVÁN, Miguel P. ROMO

期刊论文

Alternative splicing of inner-ear-expressed genes

null

期刊论文

Confined masonry as practical seismic construction alternative–the experience from the 2014 Cephalonia

Fillitsa KARANTONI, Stavroula PANTAZOPOULOU, Athanasios GANAS

期刊论文