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Value Engineering/Value Management Model and Application of Aerospace Projects

Wan-hua Qiu,Han-peng Zhang,Ze-Shui Xu,De-Sheng Wu

《工程管理前沿（英文）》 2015年 第2卷 第4期   页码 373-377 doi: 10.15302/J-FEM-2015056

摘要： This paper presents a new space model developed by general value engineering/value management model. The authors take the function analysis, function optimization and function realization of the development object as the basic point, to get the final optimization structure by value evaluation, so as to improve the project quality and reduce the project cost. The final case shows that the application of this model can save about 18% of the time and considerable cost of the usually planned projects under the condition of quality assurance.

关键词： aerospace project     value engineering     value optimization     value stream     design structure matrix    

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Anensemble method for data stream classification in the presence of concept drift

Omid ABBASZADEH,Ali AMIRI,Ali Reza KHANTEYMOORI

《信息与电子工程前沿（英文）》 2015年 第16卷 第12期   页码 1059-1068 doi: 10.1631/FITEE.1400398

摘要： One recent area of interest in computer science is data stream management and processing. By ‘data stream’, we refer to continuous and rapidly generated packages of data. Specific features of data streams are immense volume, high production rate, limited data processing time, and data concept drift; these features differentiate the data stream from standard types of data. An issue for the data stream is classification of input data. A novel ensemble classifier is proposed in this paper. The classifier uses base classifiers of two weighting functions under different data input conditions. In addition, a new method is used to determine drift, which emphasizes the precision of the algorithm. Another characteristic of the proposed method is removal of different numbers of the base classifiers based on their quality. Implementation of a weighting mechanism to the base classifiers at the decision-making stage is another advantage of the algorithm. This facilitates adaptability when drifts take place, which leads to classifiers with higher efficiency. Furthermore, the proposed method is tested on a set of standard data and the results confirm higher accuracy compared to available ensemble classifiers and single classifiers. In addition, in some cases the proposed classifier is faster and needs less storage space.

关键词： Data stream     Classificaion     Ensemble classifiers     Concept drift    

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Effects of riparian land use on water quality and fish communities in the headwater stream of the Taizi

Sen DING, Yuan ZHANG, Bin LIU, Weijing KONG, Wei MENG

《环境科学与工程前沿（英文）》 2013年 第7卷 第5期   页码 699-708 doi: 10.1007/s11783-013-0528-x

摘要： Riparian land use remains one of the most significant impacts on stream ecosystems. This study focuses on the relationship between stream ecosystems and riparian land use in headwater regions. Four riparian land types including forest, grassland, farmland, and residential land were examined to reveal the correlation between stream water and fish communities in headwater streams of the Taizi River in north-eastern China. Four land types along riparian of 3 km in length were evaluated at 25, 50, 100, 200 and 500 m widths, respectively. Generally, the results found a significant relationship between riparian land uses and stream water quality. Grassland was positively correlated with water quality parameters (conductivity and total dissolved solids) at scales from 100 to 500 m riparian width. Farmland and residential land was negatively correlated with water quality parameters at scales from 25 to 500 m and from 50 to 200 m riparian widths, respectively. Although the riparian forest is important for maintaining habitat diversity and fish communities, the results found that only fish communities were significantly correlated with the proportion of riparian farmland. Farmland had a positive correlation with individual fish abundance within a riparian corridor of 25 to 50 m, but a negative correlation with fish diversity metrics from 25 to 100 m. This study indicates that effective riparian management can improve water quality and fish communities in headwater streams.

关键词： fish     water quality     land use     riparian buffer     headwater stream    

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Residence time distribution and modeling of the liquid phase in an impinging stream reactor

Xingjun WANG, Xianhui HU, Lishun HU, Guangsuo YU, Fuchen WANG,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 353-359 doi: 10.1007/s11705-009-0262-x

摘要： Based on some experimental investigations of liquid phase residence time distribution (RTD) in an impinging stream reactor, a two-dimensional plug-flow dispersion model for predicting the liquid phase RTD in the reactor was proposed. The calculation results of the model can be in good agreement with the experimental RTD under different operating conditions. The axial liquid dispersion coefficient increases monotonously with the increasing liquid flux, but is almost independent of gas flux. As the liquid flux and the gas flux increase, the liquid dispersion coefficient of center-to-wall decreases. The axial liquid dispersion coefficient is much larger than that of center-to-wall, which indicates that the liquid RTD is dominated mainly by axial liquid dispersion in the impinging stream reactor.

关键词： RTD     liquid dispersion     reactor     liquid     independent    

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Chaotic behavior of LNG after stratification in main stream region of storage tank

WANG Jingjing, MA Xiaoqian

《能源前沿（英文）》 2008年 第2卷 第4期   页码 514-518 doi: 10.1007/s11708-008-0076-4

摘要： A study of the chaotic behavior of liquefied natural gas (LNG) after stratification in the main stream region of a storage tank was conducted. Based on non-linear dynamics, a 2-dimensional Rayleigh-Benard convection model was developed to simulate the convection, Lorenz equations of LNG convection were deduced from conservation equations, and the Runge-Kutta method was used to solve the equations. The results showed that when = 1.33, 106 < < 1470, chaos was obtained, which meant that the velocity field and the temperature field were highly unsteady. In addition, the influence of temperature and scale factor on the solutions and the corresponding range of parameters were studied. The results revealed that the chaos in LNG convection resulted from the interaction of buoyancy and viscid forces. A small quantity of heat impacting the storage tank would lead to a strong and unstable convection of LNG in the main stream region.

关键词： Runge-Kutta     non-linear     corresponding     temperature     addition    

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川江载货汽车滚装运输贡献的评估与发展政策

许茂增,吴旻

《中国工程科学》 2008年 第10卷 第2期   页码 31-34

摘要：

介绍了川江地区的运输环境，阐述了滚装运输产生的行业背景、发展历程和现 状；提出以经济、社会、运输、节能、废气排放的指标，评价川江载货汽车滚装运输对区域经济 社会发展的贡献，建立了运费节约和能源节约指标的计算模型，并以2005年的统计数据和专 项调查数据为基础进行了实际评价。结果表明，川江载货汽车滚装运输兼具降低社会运输成 本、节能、环保与生态价值，有助于长江流域经济社会的可持续发展；分析了滚装运输发展 的机遇及面临的挑战，提出了促进滚装运输发展的政策和措施。

关键词： 川江     滚装运输     评价指标     计算模型     发展政策    

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Higher heating value prediction of torrefaction char produced from non-woody biomass

Nitipong SOPONPONGPIPAT,Dussadeeporn SITTIKUL,Unchana SAE-UENG

《能源前沿（英文）》 2015年 第9卷 第4期   页码 461-471 doi: 10.1007/s11708-015-0377-3

摘要： The higher heating value of five types of non-woody biomass and their torrefaction char was predicted and compared with the experimental data obtained in this paper. The correlation proposed in this paper and the ones suggested by previous researches were used for prediction. For prediction using proximate analysis data, the mass fraction of fixed carbon and volatile matter had a strong effect on the higher heating value prediction of torrefaction char of non-woody biomass. The high ash fraction found in torrefied char resulted in a decrease in prediction accuracy. However, the prediction could be improved by taking into account the effect of ash fraction. The correlation developed in this paper gave a better prediction than the ones suggested by previous researches, and had an absolute average error (AAE) of 2.74% and an absolute bias error (ABE) of 0.52%. For prediction using elemental analysis data, the mass fraction of carbon, hydrogen, and oxygen had a strong effect on the higher heating value, while no relationship between the higher heating value and mass fractions of nitrogen and sulfur was discovered. The best correlation gave an AAE of 2.28% and an ABE of 1.36%.

关键词： higher heating value     correlation     biomass     proximate analysis     ultimate analysis    

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Value and governance of high-speed railway

Xiaoyan LIN, Zehua ZHANG, Meng WANG

《工程管理前沿（英文）》 2017年 第4卷 第4期   页码 463-482 doi: 10.15302/J-FEM-2017054

摘要： This paper considers multiple perspectives to explore the concept of high-speed railway (HSR), rationally abstract its value formation mechanism, and quantitatively measure its actual performance. This paper analyzes the governance potential of major countries in the high-speed railway value chain and studies the feasible ways and development strategies to enhance the high-speed railway governance in China. Findings of this paper are as follows. First, the government, as the early manager of high-speed railway governance, has given way to Siemens and other integrated enterprises. Second, the high-speed railway standard output has become the core competitiveness that embodies high-speed railway. Third, the global high-speed railway market presents a hierarchical high-speed railway governance model and changes to a modular approach to governance.

关键词： high-speed railway value     communication value     high-speed railway value governance     governance path upgrade    

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The value of epigenetic markers in esophageal cancer

Xiao-Mei ZHANG, Ming-Zhou GUO,

《医学前沿（英文）》 2010年 第4卷 第4期   页码 378-384 doi: 10.1007/s11684-010-0230-3

摘要： Developing esophageal cancer is a multi-step process that begins with the accumulation of genetic and epigenetic alterations, and leads to the activation of oncogenes and the inactivation or loss of tumor suppressor genes (TSG). In addition to genetic alteration, epigenetic modifications, and in particular DNA methylation, are recognized as a common molecular alteration in human tumors. In esophageal cancer, aberrant methylation of promoter regions occurs not only in advanced cancer, but also in premalignant lesions. DNA methylation is related to survival time and sensitivity of chemoradiotherapy. This review is mainly focused on epigenetic changes in esophageal cancer and the value of early detection for patient prognosis, treatment choices, and potential targeting therapy.

关键词： epigenetics     DNA methylation     esophageal cancer     dysplasia    

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On the added value of multi-scale modeling of concrete

《结构与土木工程前沿（英文）》 2022年 第16卷 第1期   页码 1-23 doi: 10.1007/s11709-021-0790-0

摘要： This review of the added value of multi-scale modeling of concrete is based on three representative examples. The first one is concerned with the analysis of experimental data, taken from four high-dynamic tests. The structural nature of the high-dynamic strength increase can be explained by using a multi-scale model. It accounts for the microstructure of the specimens. The second example refers to multi-scale thermoelastic analysis of concrete pavements, subjected to solar heating. A sensitivity analysis with respect to the internal relative humidity (RH) of concrete has underlined the great importance of the RH for an assessment of the risk of microcracking of concrete. The third example deals with multi-scale structural analysis of a real-scale test of a segmental tunnel ring. It has turned out that multi-scale modeling of concrete enables more reliable predictions of crack opening displacements in tunnel segments than macroscopic models taken from codes of practice. Overall, it is concluded that multi-scale models have indeed a significant added value. However, its degree varies with these examples. In any case, it can be assessed by means of a comparison of the results from three sources, namely, multi-scale structural analysis, conventional structural analysis, and experiments.

关键词： experiments     multi-scale analysis     conventional structural analysis     concrete     reinforced concrete    

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Observer design for induction motor: an approach based on the mean value theorem

Mohamed Yacine HAMMOUDI,Abdelkarim ALLAG,Mohamed BECHERIF,Mohamed BENBOUZID,Hamza ALLOUI

《能源前沿（英文）》 2014年 第8卷 第4期   页码 426-433 doi: 10.1007/s11708-014-0314-x

摘要： In this paper, observer design for an induction motor has been investigated. The peculiarity of this paper is the synthesis of a mono-Luenberger observer for highly coupled system. To transform the nonlinear error dynamics for the induction motor into the linear parametric varying (LPV) system, the differential mean value theorem combined with the sector nonlinearity transformation has been used. Stability conditions based on the Lyapunov function lead to solvability of a set of linear matrix inequalities. The proposed observer guarantees the global exponential convergence to zero of the estimation error. Finally, the simulation results are given to show the performance of the observer design.

关键词： observer design     differential mean value theorem (DMVT)     sector nonlinearity transformation     linear matrix inequalities (LMI)     induction motor    

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The Building of Papermaking Enterprise’s Recycling Economy Evaluation Index System Based on Value Flow

Zhi-fang Zhou,Jing Ou,Sha-sha Wang,Xiao-hong Chen

《工程管理前沿（英文）》 2016年 第3卷 第1期   页码 9-17 doi: 10.15302/J-FEM-2016009

摘要： At present, the research on circular economy has made a lot of substantive results both at home and abroad. But for the papermaking enterprise, which is the representative of the light industry, few studies have analyzed the evaluation index system of circular economy. Since the current material flow analyses have limitations that the researchers cannot calculate materials with different units. The authors take advantage of the intrinsic correlation between the basic principle of value flow analysis and circular economy, and then analyze the dynamic changes of material flow and value flow through enterprises internal production process. Considering the resource output, the authors set up the layered structure of the evaluation index system, and then preliminarily determine the index form. Next, the authors use the frequency statistics analysis method to adjust indicators, forming a preliminary index system. After that, the principal component analysis and independent analysis are applied for screening. Finally, the authors build a circular economy evaluation index system for papermaking enterprise to provide scientific guidance for the process of circular economy.

关键词： circular economy     the papermaking enterprise     material flow analysis     value flow analysis     evaluation index system    

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Does oil price affect the value of firms? Evidence from Tunisian listed firms

Kaouther ZAABOUTI,Ezzeddine BEN MOHAMED,Abdelfettah BOURI

《能源前沿（英文）》 2016年 第10卷 第1期   页码 1-13 doi: 10.1007/s11708-016-0396-8

摘要： A new debate on the potential impact of oil price changes on the value of firms was initiated in this paper. Using a stochastic frontier approach, an attempt was made to derive the optimal value * of firms and calculate the value observed. Then the shortfall ( *– ) which represents the inefficiency term was explained. Starting from 19 industrial Tunisian firms listed on the Tunis Stock Exchange between 2007 and 2011, the fact that variation of oil prices can largely explain distortions in the value of firms was empirically demonstrated.

关键词： industrial Tunisian firms     oil price     value of firm     stochastic frontier approach    

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Selective preparation for biofuels and high value chemicals based on biochar catalysts

《能源前沿（英文）》 2023年 第17卷 第5期   页码 635-653 doi: 10.1007/s11708-023-0878-4

摘要： The reuse of biomass wastes is crucial toward today’s energy and environmental crisis, among which, biomass-based biochar as catalysts for biofuel and high value chemical production is one of the most clean and economical solutions. In this paper, the recent advances in biofuels and high chemicals for selective production based on biochar catalysts from different biomass wastes are critically summarized. The topics mainly include the modification of biochar catalysts, the preparation of energy products, and the mechanisms of other high-value products. Suitable biochar catalysts can enhance the yield of biofuels and higher-value chemicals. Especially, the feedstock and reaction conditions of biochar catalyst, which affect the efficiency of energy products, have been the focus of recent attentions. Mechanism studies based on biochar catalysts will be helpful to the controlled products. Therefore, the design and advancement of the biochar catalyst based on mechanism research will be beneficial to increase biofuels and the conversion efficiency of chemicals into biomass. The advanced design of biochar catalysts and optimization of operational conditions based on the biomass properties are vital for the selective production of high-value chemicals and biofuels. This paper identifies the latest preparation for energy products and other high-value chemicals based on biochar catalysts progresses and offers insights into improving the yield of high selectivity for products as well as the high recyclability and low toxicity to the environment in future applications.

关键词： biomass     biochar catalysts     biofuels     high chemicals    

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工程化仿生血小板膜包覆纳米颗粒阻断金黄色葡萄球菌的细胞毒性并防止致命的全身感染 Article

Jwa-Kyung Kim, Satoshi Uchiyama, Hua Gong, Alexandra Stream, Liangfang Zhang, Victor Nizet

《工程（英文）》 2021年 第7卷 第8期   页码 1149-1156 doi: 10.1016/j.eng.2020.09.013

摘要：

金黄色葡萄球菌（S. aureus）是一种常见的人类病原体，它可以引发严重的侵袭性感染，如菌血症、败血症和心内膜炎，具有较高的发病率和死亡率。然而由于细菌的抗生素耐药性增强，如耐甲氧西林金黄色葡萄球菌（MRSA），加剧了此类细菌的发病率和死亡率。金黄色葡萄球菌的发病机制是由毒素的分泌推动的，如膜损伤孔α毒素，它有不同的细胞靶点，包括上皮细胞、内皮细胞、白细胞和血小板。本文采用人体血小板膜包覆纳米颗粒（PNP）作为一种仿生诱饵策略，来中和金黄色葡萄球菌的毒素，并维持宿主细胞的防御功能。血小板膜包覆纳米颗粒保护血小板免受由金黄色葡萄球菌毒素带来的损伤，维持血小板活化和杀菌活性。血小板膜包覆纳米颗粒也同样保护巨噬细胞免受由金黄色葡萄球菌毒素带来的损伤，支持巨噬细胞进行氧化迸发、产生一氧化氮和维持其杀菌活性，并减少耐甲氧西林金黄色葡萄球菌诱导的中性粒细胞胞外杀菌网络。在感染系统性耐甲氧西林金黄色葡萄球菌的小鼠模型中，血小板膜包覆纳米颗粒制剂减少了血液中的细菌数量并防止小鼠发生死亡。总之，目前的研究结果证明了血小板膜包覆纳米颗粒的治疗优点，如中和毒素、保护细胞和增加宿主对侵袭性金黄色葡萄球菌感染的抵抗力。

关键词： 纳米颗粒     纳米海绵     血小板     金黄色葡萄球菌     细菌毒素     败血症    

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标题 作者 时间 类型 操作

Value Engineering/Value Management Model and Application of Aerospace Projects

Wan-hua Qiu,Han-peng Zhang,Ze-Shui Xu,De-Sheng Wu

期刊论文

Anensemble method for data stream classification in the presence of concept drift

Omid ABBASZADEH,Ali AMIRI,Ali Reza KHANTEYMOORI

期刊论文

Effects of riparian land use on water quality and fish communities in the headwater stream of the Taizi

Sen DING, Yuan ZHANG, Bin LIU, Weijing KONG, Wei MENG

期刊论文

Residence time distribution and modeling of the liquid phase in an impinging stream reactor

Xingjun WANG, Xianhui HU, Lishun HU, Guangsuo YU, Fuchen WANG,

期刊论文

Chaotic behavior of LNG after stratification in main stream region of storage tank

WANG Jingjing, MA Xiaoqian

期刊论文

川江载货汽车滚装运输贡献的评估与发展政策

许茂增,吴旻

期刊论文

Higher heating value prediction of torrefaction char produced from non-woody biomass

Nitipong SOPONPONGPIPAT,Dussadeeporn SITTIKUL,Unchana SAE-UENG

期刊论文

Value and governance of high-speed railway

Xiaoyan LIN, Zehua ZHANG, Meng WANG

期刊论文

The value of epigenetic markers in esophageal cancer

Xiao-Mei ZHANG, Ming-Zhou GUO,

期刊论文

On the added value of multi-scale modeling of concrete

期刊论文

Observer design for induction motor: an approach based on the mean value theorem

Mohamed Yacine HAMMOUDI,Abdelkarim ALLAG,Mohamed BECHERIF,Mohamed BENBOUZID,Hamza ALLOUI

期刊论文

The Building of Papermaking Enterprise’s Recycling Economy Evaluation Index System Based on Value Flow

Zhi-fang Zhou,Jing Ou,Sha-sha Wang,Xiao-hong Chen

期刊论文

Does oil price affect the value of firms? Evidence from Tunisian listed firms

Kaouther ZAABOUTI,Ezzeddine BEN MOHAMED,Abdelfettah BOURI

期刊论文

Selective preparation for biofuels and high value chemicals based on biochar catalysts

期刊论文

工程化仿生血小板膜包覆纳米颗粒阻断金黄色葡萄球菌的细胞毒性并防止致命的全身感染

Jwa-Kyung Kim, Satoshi Uchiyama, Hua Gong, Alexandra Stream, Liangfang Zhang, Victor Nizet

期刊论文