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Detection of schedule delay risk of empirical construction projects

Tsegay GEBREHIWET, Hanbin LUO

《工程管理前沿（英文）》 2018年 第5卷 第2期   页码 251-267 doi: 10.15302/J-FEM-2018086

摘要： In Ethiopian construction projects, schedule delay risk is a predominant issue because it is not properly addressed. Although several studies have been focused on the various effects of risk in construction projects, limited efforts have been made to investigate the typical and the overall schedule delay risk. In this study, our aim is to detect the typical and overall schedule delay risk throughout the construction project lifecycle, which consists of the pre-construction, construction, and post-construction stages, and compare the stages with each other. Common criteria, sub-criteria, and attributes were developed for all alternatives for the purpose of making a risk decision. The methodology that was followed integrated the multiple-criteria decision-making (MCDM) model of fuzzy analytic hierarchy process comprehensive evaluation (FAHPCE) and the relative important index (RII). Data were collected from 77 participants, who were selected through purposive sampling from different contracting organizations in Ethiopian construction projects by means of questionnaires that were distributed to experienced experts. The findings showed that there is a typical delay risk either in the type or in the level of the different construction activities. Consequently, the most influenced alternative is the construction stage because of the high-risk responsibility, resource, and contract condition related criteria. The post-construction stage was the second most influenced stage because of the high-risk responsibility-related criteria. The pre-constructed stage was the least influenced stage that consist high-risk criteria of responsibility, resource, and contract condition related. These differences provided noteworthy information about risk mitigation in construction projects by identifying the exact risk level on specific activity to make appropriate decision.

关键词： fuzzy analytic hierarchy process comprehensive evaluation     construction project     detection of delay risk     relative important index    

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Contact of surfaces and contact characteristics of offset surfaces

CAO Lixin, GONG Hu, LIU Jian

《机械工程前沿（英文）》 2008年 第3卷 第3期   页码 318-324 doi: 10.1007/s11465-008-0067-5

摘要： Based on differential geometry, the contact problems of two surfaces are discussed in this paper. The relationship between the contact status of two surfaces and that of offset surfaces are also analyzed. For a 5-axis NC machining, some research such as optimization of cutter location and calculation of the geometrical cusp height are important. The research results indicate that the relative normal curvature is an important geometrical invariant for describing the contact state of two surfaces. For point contact two surfaces, the calculation equation for the second order remained error is given. For line contact two surfaces, the condition of the second order line contact is that the principal directions and curvatures of the two surfaces are the same along the contact curve. If two surfaces keep the second order line contact, their two offset surfaces will also keep the second order line contact, and their third order remained errors are also uniform with that of the two offset surfaces.

关键词： relative     important geometrical     relationship     geometrical invariant     calculation    

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Identification of important precursors and theoretical toxicity evaluation of byproducts driving cytotoxicity

Qian-Yuan Wu, Yi-Jun Yan, Yao Lu, Ye Du, Zi-Fan Liang, Hong-Ying Hu

《环境科学与工程前沿（英文）》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1204-6

摘要： • NOM formed more C-DBPs while amino acids formed more N-DBPs during chlorination • Aspartic acid and asparagine showed the highest toxicity index during chlorination • Dichloroacetonitrile might be a driving DBP for cytotoxicity and genotoxicity • Dichloroacetonitrile dominated the toxicity under different chlorination conditions Chlorination, the most widely used disinfection process for water treatment, is unfortunately always accompanied with the formation of hazardous disinfection byproducts (DBPs). Various organic matter species, like natural organic matter (NOM) and amino acids, can serve as precursors of DBPs during chlorination but it is not clear what types of organic matter have higher potential risks. Although regulation of DBPs such as trihalomethanes has received much attention, further investigation of the DBPs driving toxicity is required. This study aimed to identify the important precursors of chlorination by measuring DBP formation from NOM and amino acids, and to determine the main DBPs driving toxicity using a theoretical toxicity evaluation of contributions to the cytotoxicity index (CTI) and genotoxicity index (GTI). The results showed that NOM mainly formed carbonaceous DBPs (C-DBPs), such as trichloromethane, while amino acids mainly formed nitrogenous DBPs (N-DBPs), such as dichloroacetonitrile (DCAN). Among the DBPs, DCAN had the largest contribution to the toxicity index and might be the main driver of toxicity. Among the precursors, aspartic acid and asparagine gave the highest DCAN concentration (200 g/L) and the highest CTI and GTI. Therefore, aspartic acid and asparagine are important precursors for toxicity and their concentrations should be reduced as much as possible before chlorination to minimize the formation of DBPs. During chlorination of NOM, tryptophan, and asparagine solutions with different chlorine doses and reaction times, changes in the CTI and GTI were consistent with changes in the DCAN concentration.

关键词： Chlorination     Dichloroacetonitrile     Aspartic acid     Asparagine     Toxicity index    

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EXPLORING THE RELATIVE ADVANTAGES OF LOCAL INNOVATION IN AGROFORESTRY

《农业科学与工程前沿（英文）》 2023年 第10卷 第1期   页码 61-72 doi: 10.15302/J-FASE-2022476

摘要：

● Promotion of local sustainable innovation developed by forest farmers.

关键词： agroforestry     forest farmers     local innovation     relative advantage     social forestry    

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负能量问题——超光速研究的重要方向

黄志洵

《中国工程科学》 2001年 第3卷 第7期   页码 42-47

摘要：

论述了关于负能量的多个理论预期和相关实验，阐明了超光速研究和负能量概念的关系。

关键词： 负能量     超光速     Casimir效应     消失模     负折射率    

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A combined control strategy using tuned liquid dampers to reduce displacement demands of base-isolated structures: a probabilistic approach

Parham SHOAEI, Houtan Tahmasebi OROMI

《结构与土木工程前沿（英文）》 2019年 第13卷 第4期   页码 890-903 doi: 10.1007/s11709-019-0524-8

摘要： This paper investigates a hybrid structural control system using tuned liquid dampers (TLDs) and lead-rubber bearing (LRB) systems for mitigating earthquake-induced vibrations. Furthermore, a new approach for taking into account the uncertainties associated with the steel shear buildings is proposed. In the proposed approach, the probabilistic distributions of the stiffness and yield properties of stories of a set of reference steel moment frame structures are derived through Monte-Carlo sampling. The approach is applied to steel shear buildings isolated with LRB systems. The base isolation systems are designed for different target base displacements by minimizing a relative performance index using Genetic Algorithm. Thereafter, the base-isolated structures are equipped with TLDs and a combination of the base and TLD properties is sought by which the maximum reduction occurs in the base displacement without compromising the performance of the system. In addition, the effects of TLD properties on the performance of the system are studied through a parametric study. Based on the analyses results, the base displacement can be reduced 23% by average, however, the maximum reduction can go beyond 30%.

关键词： tuned liquid damper     lead-rubber bearing system     probabilistic framework     steel shear building     relative performance index     Monte-Carlo sampling    

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Measurement of bone alkaline phosphatase and relative study with osteosarcoma

YANG Zhiping, LI Jianmin, LI Xin, HUO Yanqing, SUN Guangzhi

《医学前沿（英文）》 2007年 第1卷 第1期   页码 54-57 doi: 10.1007/s11684-007-0011-9

摘要： The objective of this paper is to explore the value of bone alkaline phosphatase (BALP) for diagnosing osteosarcoma, evaluating the effect of the chemotherapy, judging the prognosis and supervising the relapse and metastasis. The immunoassay was used to check the BALP of the blood serum that was from 42 primary osteosarcoma patients. Alkaline phosphatase (ALP) in blood serum was checked with auto biochemistry equipment. The biopsy tissue and the lesion resected in operation were treated with pathology and histological response was counted. The patients were followed up from five months to 49 months with an average of 24.3 months. Eighteen cases relapsed and transferred, among which, 16 of them were dead, and others were survival to the end of the follow-up. BALP was more sensitive than ALP in diagnosing osteosarcoma ( = 0.015). Fifteen cases decreased to normal value in ALP after preoperative chemotherapy, and 34 cases decreased in BALP. Both ALP and BALP in all cases decreased to normal value in postoperative. There was significant difference in positive correlation between the decrease of BALP and the increase of histological response ( = 0.001, = 0.642). In the followup, there was significant difference in BALP between the group of relapse and transfer and the group of free disease survival ( = 0.000). As a check marker in blood serum, BALP, reflecting the process of ossification, has a higher sensitivity than ALP. It has applied value in the diagnosis of osteosarcoma, reflection of the effect of chemotherapy and forecast the prognosis.
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Evaluation of the relative risk of stroke in patients with hypertension using cerebrovascular hemodynamic

HUANG Jiuyi, WANG Guiqing, GUO Jiping, CAO Yifeng, WANG Yan, YANG Yongju, YU Xuehai

《医学前沿（英文）》 2007年 第1卷 第3期   页码 274-278 doi: 10.1007/s11684-007-0052-0

摘要： The relative risk (RR) of stroke in patients with hypertension was evaluated by using synthetic index of cerebrovascular hemodynamics. A total of 7,371 patients with hypertension with ages ≥40 years were selected from a population-based cohort study of the risk factors for stroke. The data on the baseline investigation of risk factors, the determination of cerebrovascular hemodynamic parameters (CVHP), and stroke follow-up were analyzed. The RR of stroke in patients with hypertension was evaluated by CVHP scores. Univariate analysis indicated that hypertension, complicated by other risk factors, had significant statistical association with the onset of stroke. RRs for stroke when hypertension complicated with decrease of hemodynamic scores, heart disease, cigarette smoking and alcohol consumption were 4.93 (95%CI, 3.26–7.45), 1.90 (95%CI, 1.36–2.66), 1.99 (95%CI, 1.42–2.79) and 1.73 (95%CI, 1.19–2.53) respectively. In multivariate analysis, hemodynamic score, age, sex, cigarette smoking, family history of stroke and systolic blood pressure were selected by the Cox regression for inclusion in the final analysis. Among them, the RR of hemodynamic score was highest. The analysis of doseresponse relationships indicated that when the hemodynamic scores in patients with hypertension were lower than 75 points, the RR of stroke at 75, 60, 45, 30 and 15 points were 2.85, 4.43, 4.54, 5.40 and 9.88, respectively. The risk of stroke in patients with hypertension is closely asso ciated with hemodynamic impairment and the hemodynamic score may be used for quantitative evaluation of relative risks of stroke.

关键词： inclusion     quantitative evaluation     cerebrovascular     relative     decrease    

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Elements’ important ranking of China drug safety management system: applying the non-structural

Xiaoping ZHENG, Xiaocui WANG, Tingkuan ZHONG,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 290-299 doi: 10.1007/s11705-009-0283-5

摘要： Drug safety management is an important issue in China drug management system and attracts great attentions from the whole society. In order to reduce drug incident, this study discusses some important elements associated with China drug safety management system and analyzes the data collected by questionnaires. Besides, a methodology for rating the important elements is described and applied. The non-structural fuzzy group decision method not only considers the insufficient precise information but also combines the opinions of different kinds of respondents in China’s four municipalities. The results indicate that the sample systems are the most important in these important elements, and the order of importance is sampling systems, licensing systems, traceability systems, transaction models, pharmacovigilance and emergence management. This study not only points out the important ranking of the pivotal elements in China drug safety management but also gives some specific proposals about how to enhance drug safety management in China.

关键词： management system     different     management     important ranking     non-structural fuzzy    

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Presentation of machine learning methods to determine the most important factors affecting road traffic

Hamid MIRZAHOSSEIN; Milad SASHURPOUR; Seyed Mohsen HOSSEINIAN; Vahid Najafi Moghaddam GILANI

《结构与土木工程前沿（英文）》 2022年 第16卷 第5期   页码 657-666 doi: 10.1007/s11709-022-0827-z

摘要： The purpose of this research was to develop statistical and intelligent models for predicting the severity of road traffic accidents (RTAs) on rural roads. Multiple Logistic Regression (MLR) was used to predict the likelihood of RTAs. For more accurate prediction, Multi-Layer Perceptron (MLP) and Radius Basis Function (RBF) neural networks were applied. Results indicated that in MLR, the model obtained from the backward method with the correct percent of 84.7% and R2 value of 0.893 was the best method for predicting the likelihood of RTAs. Also, MLR showed that the variables of not paying attention to the front not paying attention to the frontroad ahead, followed byand then vehicle-motorcycle/bike accidents were the greatest problems. Among the models, MLP had a better performance, so that the prediction accuracy of MLR, MLP, and RBF were 84.7%, 96.7%, and 92.1%, respectively. MLP model, due to higher accuracy, showed that the variable of reason of accident had the highest effect on the prediction of accidents, and considering MLR results, the variables of not paying attention to the front and then vehicle-motorcycle/bike accidents had the most influence on the occurrence of accidents. Therefore, motorcyclists and cyclists are more prone to accidents, and appropriate solutions should be adopted to enhance their safety.

关键词： safety     rural accidents     multiple logistic regression     artificial neural networks    

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Genomic regions under selection for important traits in domestic horse breeds

Xuexue LIU, Yuehui MA, Lin JIANG

《农业科学与工程前沿（英文）》 2017年 第4卷 第3期   页码 289-294 doi: 10.15302/J-FASE-2017155

摘要： Horses were domesticated 5500 years ago, thousands of years later than other domestic animals; however, in this relatively short period, domestic horses have had a great impact on human history by accelerating civilization, revolutionizing warfare and advancing agricultural production. Modern breeding using marker-assisted selection has greatly accelerated breeding progress. Therefore, identification of genetic markers underlying the traits of interest in domestic horses is the basis for the modern breeding system. In this review, we present an overview of genetic mapping studies and genome wide analyses to identify the genomic regions targeted by positive selection for four important aspects of horses, coat color, racing performance, gait and height at withers. The locus, for example, has been shown to be the main gene responsible for chestnut color, and the locus has been shown to control the muscle fiber growth in racing breeds. The missense mutation in is the causal mutation for the alternate gaits in horses. Height at withers, a quantitative trait, was mapped to four major loci (3:105547002, 6:81481064, 9:75550059 and 11:232597 32) that can explain 83% of the height variations in domestic horses.

关键词： horse     coat color     racing performance     gait     height    

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Recent advances in understanding genetic variants associated with economically important traits in sheep

Song-Song XU, Meng-Hua LI

《农业科学与工程前沿（英文）》 2017年 第4卷 第3期   页码 279-288 doi: 10.15302/J-FASE-2017151

摘要： Sheep are one of the most economically important domesticated animals for human society. However, genetic improvements for the key traits associated with meat, growth, milk, wool, reproduction, horns and tails progress slowly using conventional crossbreeding methods. With the development and utilization of high-throughput screening technologies over the last decade, a list of functional genes and genetic variants associated with these traits has been identified. This review covers recent genome-wide studies on sheep productive traits using high-throughput screening technologies, including those based on single-nucleotide polymorphisms and copy number variants at the whole-genome level (e.g., genome-wide association studies), transcriptome and DNA methylation sequences. Additionally, comprehensive information on functional genes and genetic variants associated with economically important traits in sheep is provided.

关键词： sheep     high-throughput screening     productive traits     genome-wide studies    

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palladium prepared by activated sludge microbes for the hexavalent chromium catalytic reduction: Impact of relative

Luman Zhou, Chengyang Wu, Yuwei Xie, Siqing Xia

《环境科学与工程前沿（英文）》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1206-4

摘要： • Pd nanoparticles could be reduced and supported by activated sludge microbes. • The effect of biomass on Pd adsorption by microbes is greater than Pd reduction. • More biomass reduces Pd particle size, which is more dispersed on the cell surface. • When the biomass/Pd add to 6, the catalytic reduction rate of Cr(VI) reaches stable. Palladium, a kind of platinum group metal, owns catalytic capacity for a variety of hydrogenations. In this study, Pd nanoparticles (PdNPs) were generated through enzymatic recovery by microbes of activated sludge at various biomass/Pd, and further used for the Cr(VI) reduction. The results show that biomass had a strong adsorption capacity for Pd(II), which was 17.25 mg Pd/g sludge. The XRD and TEM-EDX results confirmed the existence of PdNPs associated with microbes (bio-Pd). The increase of biomass had little effect on the reduction rate of Pd(II), but it could cause decreasing particle size and shifting location of Pd(0) with the better dispersion degree on the cell surface. In the Cr(VI) reduction experiments, Cr(VI) was first adsorbed on bio-Pd with hydrogen and then reduced using active hydrogen as electron donor. Biomass improved the catalytic activity of PdNPs. When the biomass/Pd (w/w) ratio increased to six or higher, Cr(VI) reduction achieved maximum rate that 50 mg/L of Cr(VI) could be rapidly reduced in one minute.

关键词： Palladium nanoparticles     Activated sludge     Hexavalent chromium    

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知识发现领域中当今面临的五类重大问题

杨炳儒

《中国工程科学》 2009年 第11卷 第4期   页码 76-83

摘要：

系统地总结与提出知识发现(KD)领域中当今面临的五类重大问题，它们是KD中的两大核心问题、两大猜想问题、主流发展中富有挑战性的问题、应用研究中的相关领域重大问题以及KD技术标准的制定问题，并给出其部分成果或具体分析。这五类问题密切相关，对它们的研究必将KD推向新的发展阶段,并在该领域内外产生深刻的影响。

关键词： KD核心问题     KD猜想     KD挑战性问题     蛋白质二级结构预测     KD技术标准    

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Relative expression of PTTG and bFGF in oral squamous cell carcinoma and Tca8113

Yumei DING BM , Lili CHEN MD , Bo CHENG PhD , Handong ZHANG MM ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 357-362 doi: 10.1007/s11684-009-0046-1

摘要： The purpose of this study was to investigate the expression of pituitary tumor transforming gene (PTTG) and basic fibroblast growth factor (bFGF) in oral squamous cell carcinoma (OSCC) and tongue cancer cell line Tca8113, as well as their effects on each other. We detected PTTG protein and bFGF in OSCC tissues from 56 cases using the streptavidin-biotin peroxidase (S-P) method; additionally, after being treated with different concentrations of anti bFGF or PTTG antibody, PTTG or bFGF expression in Tca8113 was examined by immunocytochemistry. The results were as follows: (1) Positive rates of PTTG protein and bFGF were 78.2% and 67.3% in OSCC, respectively, which were significantly higher than those in normal mucosal tissues (<0.05). PTTG protein was significantly up-regulated in poorly and moderately differentiated tumors compared to well differentiated tumors (<0.05), and there was also a significant difference between tumors with lymph node metastasis and tumors without lymph node metastasis (<0.05). PTTG protein expression was positively correlated with bFGF ( = 0.382, <0.05); (2) PTTG protein emitted strong fluorescence in Tca8113, and it decreased after being treated with anti-bFGF antibody. Anti-PTTG antibody also had an inhibitive effect on bFGF expression. In summary, the overexpression of PTTG protein is closely related with OSCC differentiation and lymph node metastasis. PTTG protein expression conforms to bFGF in OSCC tissues and Tca8113 cells. Detection of both PTTG and bFGF may help to judge the degree of malignancy and prognosis of patients with OSCC.

关键词： carcinoma     squamous cell     pituitary tumor transforming gene (PTTG) protein     basic fibroblast growth factor    

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标题 作者 时间 类型 操作

Detection of schedule delay risk of empirical construction projects

Tsegay GEBREHIWET, Hanbin LUO

期刊论文

Contact of surfaces and contact characteristics of offset surfaces

CAO Lixin, GONG Hu, LIU Jian

期刊论文

Identification of important precursors and theoretical toxicity evaluation of byproducts driving cytotoxicity

Qian-Yuan Wu, Yi-Jun Yan, Yao Lu, Ye Du, Zi-Fan Liang, Hong-Ying Hu

期刊论文

EXPLORING THE RELATIVE ADVANTAGES OF LOCAL INNOVATION IN AGROFORESTRY

期刊论文

负能量问题——超光速研究的重要方向

黄志洵

期刊论文

A combined control strategy using tuned liquid dampers to reduce displacement demands of base-isolated structures: a probabilistic approach

Parham SHOAEI, Houtan Tahmasebi OROMI

期刊论文

Measurement of bone alkaline phosphatase and relative study with osteosarcoma

YANG Zhiping, LI Jianmin, LI Xin, HUO Yanqing, SUN Guangzhi

期刊论文

Evaluation of the relative risk of stroke in patients with hypertension using cerebrovascular hemodynamic

HUANG Jiuyi, WANG Guiqing, GUO Jiping, CAO Yifeng, WANG Yan, YANG Yongju, YU Xuehai

期刊论文

Elements’ important ranking of China drug safety management system: applying the non-structural

Xiaoping ZHENG, Xiaocui WANG, Tingkuan ZHONG,

期刊论文

Presentation of machine learning methods to determine the most important factors affecting road traffic

Hamid MIRZAHOSSEIN; Milad SASHURPOUR; Seyed Mohsen HOSSEINIAN; Vahid Najafi Moghaddam GILANI

期刊论文

Genomic regions under selection for important traits in domestic horse breeds

Xuexue LIU, Yuehui MA, Lin JIANG

期刊论文

Recent advances in understanding genetic variants associated with economically important traits in sheep

Song-Song XU, Meng-Hua LI

期刊论文

palladium prepared by activated sludge microbes for the hexavalent chromium catalytic reduction: Impact of relative

Luman Zhou, Chengyang Wu, Yuwei Xie, Siqing Xia

期刊论文

知识发现领域中当今面临的五类重大问题

杨炳儒

期刊论文

Relative expression of PTTG and bFGF in oral squamous cell carcinoma and Tca8113

Yumei DING BM , Lili CHEN MD , Bo CHENG PhD , Handong ZHANG MM ,

期刊论文