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Seepage failure by heave in sheeted excavation pits constructed in stratified cohesionless soils

Serdar KOLTUK, Jie SONG, Recep IYISAN, Rafig AZZAM

《结构与土木工程前沿（英文）》 2019年 第13卷 第6期   页码 1415-1431 doi: 10.1007/s11709-019-0565-z

摘要： In this study, experimental and numerical investigations are performed to clarify the seepage failure by heave in sheeted excavation pits in stratified cohesionless soils in which a relatively permeable soil layer ( ) lies above a less permeable soil layer ( ) between excavation base and wall tip. It is shown that the evaluation of base stabilities of excavation pits against seepage failure by using Terzaghi and Peck’s approach leads to considerably lower critical potential differences than those obtained from the model tests. On the other hand, a relatively good agreement is achieved between the results of the model tests and the finite element (FE) analyses. Further investigations are performed by using axisymmetric excavation models with various dimensions and ground conditions, and a comparison between the results obtained from Terzaghi and Peck’s approach and finite element analyses is given.

关键词： seepage failure by heave     cohesionless stratified soil     model test     Terzaghi and Peck’s approach     FE analysis    

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Governance approach to China’s environmental challenges: Towards a theoretical synthesis

QI Ye, XUE Lan, ZHANG Lingyun

《环境科学与工程前沿（英文）》 2007年 第1卷 第4期   页码 385-400 doi: 10.1007/s11783-007-0066-5

摘要： This paper reviewed recent research in environmental governance as a response to environmental challenges at various spatial, temporal and administrative scales. It documented the shift of approach from regulation to governance, and attempted to provide a comprehensive understanding why and how the transformation occurred. It also described major factors and forces of environmental governance, and discussed research advance in environmental governance theory. Finally, this paper summarized recent research findings on environmental governance in China, and listed policy recommendation for enhancing the governance.

关键词： environmental governance     approach     temporal     regulation     various    

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Simultaneous harvesting and cell disruption of microalgae using ozone bubbles: optimization and characterization study for biodiesel production

Lim, Peck L. Kiew, Steven Lim, Siti S. Rosli, Chung Y. Wong, Pau L. Show, Keat T. Lee

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1257-1268 doi: 10.1007/s11705-020-2015-9

摘要： In the present study, ozone was introduced as an alternative approach to harvest and disrupt microalgae cells ( ) simultaneously for biodiesel production. At the optimum ozonation conditions (6.14 g·h ozone concentration, 30 min ozonation time, 1 L·min of ozone flowrate at medium pH of 10 and temperature of 30 °C), the sedimentation efficiency of microalgae cells increased significantly from 12.56% to 68.62%. It was observed that the microalgae cells aggregated to form flocs after pre-treated with ozone due to the increment of surface charge from –20 to –6.59 mV. Besides, ozone had successfully disrupted the microalgae cells and resulted in efficient lipid extraction, which was 1.9 times higher than the control sample. The extracted microalgae lipid was mainly consisted of methyl palmitate (C16:0), methyl oleate (C18:1) and methyl linolenate (C18:3), making it suitable for biodiesel production. Finally, utilization of recycled culture media after ozonation pre-treatment showed robust growth of microalgae, in which the biomass yield was maintained in the range of 0.796 to 0.879 g·h for 5 cycles of cultivation.

关键词： microalgae     biodiesel     ozonation     pre-treatment     lipid    

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A novel approach for remanufacturing process planning considering uncertain and fuzzy information

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 546-558 doi: 10.1007/s11465-021-0639-1

摘要： Remanufacturing, as one of the optimal disposals of end-of-life products, can bring tremendous economic and ecological benefits. Remanufacturing process planning is facing an immense challenge due to uncertainties and fuzziness of recoverable products in damage conditions and remanufacturing quality requirements. Although researchers have studied the influence of uncertainties on remanufacturing process planning, very few of them comprehensively studied the interactions among damage conditions and quality requirements that involve uncertain, fuzzy information. Hence, this challenge in the context of uncertain, fuzzy information is undertaken in this paper, and a method for remanufacturing process planning is presented to maximize remanufacturing efficiency and minimize cost. In particular, the characteristics of uncertainties and fuzziness involved in the remanufacturing processes are explicitly analyzed. An optimization model is then developed to minimize remanufacturing time and cost. The solution is provided through an improved Takagi–Sugeno fuzzy neural network (T-S FNN) method. The effectiveness of the proposed approach is exemplified and elucidated by a case study. Results show that the training speed and accuracy of the improved T-S FNN method are 23.5% and 82.5% higher on average than those of the original method, respectively.

关键词： remanufacturing     uncertain and fuzzy information     process planning     T-S FNN    

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Optimization of WEDM process of pure titanium with multiple performance characteristics using Taguchi’sDOE approach and utility concept

Rupesh CHALISGAONKAR, Jatinder KUMAR

《机械工程前沿（英文）》 2013年 第8卷 第2期   页码 201-214 doi: 10.1007/s11465-013-0256-8

摘要：

This paper describes the development of multi response optimization technique using utility method to predict and select the optimal setting of machining parameters in wire electro-discharge machining (WEDM) process. The experimental studies in WEDM process were conducted under varying experimental conditions of process parameters, such as pulse on time(Ton), pulse off time(Toff), peak current (IP), wire feed (WF), wire tension (WT) and servo voltage (SV) using pure titanium as work material. Experiments were planned using Taguchi’s L27 orthogonal array. Multi response optimization was performed for both cutting speed (CS) and surface roughness (SR) using utility concept to find out the optimal process parameter setting. The level of significance of the machining parameters for their effect on the CS and SR was determined by using analysis of variance (ANOVA). Finally, confirmation experiment was performed to validate the effectiveness of the proposed optimal condition.

关键词： wire electro-discharge machining (WEDM)     Taguchi method     analysis of variance (ANOVA)     utility concept     cutting speed (CS)     surface roughness (SR)    

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RePizer：一种软件需求排序架构 Article

Saif Ur Rehman KHAN,Sai Peck LEE,Mohammad DABBAGH1,Muhammad TAHIR,Muzafar KHAN,Muhammad ARIF

《信息与电子工程前沿（英文）》 2016年 第17卷 第8期   页码 750-765 doi: 10.1631/FITEE.1500162

摘要： 标准的软件开发周期很大程度上取决于利益相关方的需求。软件开发全程围绕需求设计和管理。考虑到时间和资源的限制，必须分清哪些是必须首先考虑的高优先级需求。已有的需求排序架构缺少对历史数据的记录，而这些历史数据有助于从类似项目中方便地选取最适合的需求排序技术。本文中，我们提出一种名为RePizer的软件需求排序架构，该架构与一种选定的需求排序技术联合使用，可以基于给定标准(如开发成本)，为软件需求优先级排序。RePizer通过从需求库提取历史数据，为软件需求工程师决策提供协助。此外，RePizer提供了对整个项目的全景式视角，以确保对资源的审慎使用。基于RePizer架构，采用已有的两种需求排序技术：计划博弈(planning game, PG)和层级分析(analytical hierarchy process, AHP)，分别比较各自的预期准确度和易用程度。结果表明，采用计划博弈时，RePizer性能更佳。

关键词： 软件需求；需求排序技术；排序架构；计划博弈；层级分析    

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A Bayesian modeling approach to bi-directional pedestrian flows in carnival events

S. Q. XIE, S. C. WONG, William H. K. LAM

《工程管理前沿（英文）》 2017年 第4卷 第4期   页码 483-489 doi: 10.15302/J-FEM-2017023

摘要： Bi-directional pedestrian flows are common at crosswalks, footpaths, and shopping areas. However, the properties of pedestrian movement may vary in urban areas according to the type of walking facility. In recent years, crowd movements at carnival events have attracted the attention of researchers. In contrast to pedestrian behavior in other walking facilities, pedestrians whose attention is attracted by carnival displays or activities may slow down and even stop walking. The Lunar New Year Market is a traditional carnival event in Hong Kong held annually one week before the Lunar New Year. During the said event, crowd movements can be easily identified, particularly in Victoria Park, where the largest Lunar New Year Market in Hong Kong is hosted. In this study, we conducted a video-based observational survey to collect pedestrian flow and speed data at the Victoria Park Lunar New Year Market on the eve of the Lunar New Year. Using the collected data, an extant mathematical model was calibrated to capture the relationships between the relevant macroscopic quantities, thereby providing insight into pedestrian behavior at the carnival event. Bayesian inference was employed to calibrate the model by using prior data obtained from a previous controlled experiment. Results obtained enhance our understanding of crowd behavior under different conditions at carnival events, thus facilitating the improvement of the safety and efficiency of similar events in the future.

关键词： pedestrian flow model     bi-directional interactions     empirical studies     Bayesian inference    

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A new and best approach for early detection of rotor and stator faults in induction motors coupled to

Abderrahim ALLAL,Boukhemis CHETATE

《能源前沿（英文）》 2016年 第10卷 第2期   页码 176-191 doi: 10.1007/s11708-015-0386-2

摘要： Today, induction machines are playing, thanks to their robustness, an important role in world industries. Although they are quite reliable, they have become the target of various types of defects. Thus, for a long time, many research laboratories have been focusing their works on the theme of diagnosis in order to find the most efficient technique to predict a fault in an early stage and to avoid an unplanned stopping in the chain of production and costs ensuing. In this paper, an approach called Park’s vector product approach (PVPA) was proposed which was endowed with a dominant sensitivity in the case in which there would be rotor or stator faults. To show its high sensitivity, it was compared with the classical methods such as motor current signature analysis (MCSA) and techniques studied in recent publications such as motor square current signature analysis (MSCSA), Park’s vector square modulus (PVSM) and Park-Hilbert (P-H) (PVSM ). The proposed technique was based on three main steps. First, the three-phase currents of the induction motor led to a Park’s vector. Secondly, the proposed PVPA was calculated to show the distinguishing spectral signatures of each default and specific frequencies. Finally, simulation and experimental results were presented to confirm the theoretical assumptions.

关键词： induction motor     incipient broken bar     extended Park’s vector approach     spectral analysis     inter-turn short-circuit     Hilbert transform    

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One-dimensional consolidation of over-consolidated soil under time-dependent loading

XIE Kanghe, WANG Kun, CHEN Guohong, HU Anfeng

《结构与土木工程前沿（英文）》 2008年 第2卷 第1期   页码 67-72 doi: 10.1007/s11709-008-0009-7

摘要： The problem of one-dimensional consolidation of over-consolidated saturated soil under time-dependent loading was studied based on semi-analytical method. The relevant computer code was developed by FORTRAN programming, and one-dimensional consolidation behavior of over-consolidated soil was investigated. It is shown that, unlike this described by traditional Terzaghi’s consolidation theory, the rate of excess pore water pressure dissipation is different from that of settlement developing. The magnitude of load and that of pre-consolidation pressure as well as the loading rate has all significant influence on consolidation. With the increasing of pre-consolidation pressure and loading rate, the rate of consolidation increases correspondingly. However, an increase in load will slow down the consolidation rate.

关键词： different     FORTRAN programming     Terzaghi ’     pre-consolidation     magnitude    

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A multi-integrated approach on toxicity effects of engineered TiO

PAIXÃO,Liliana MOITA,Luis SILVA,Mário S.

《环境科学与工程前沿（英文）》 2015年 第9卷 第5期   页码 793-803 doi: 10.1007/s11783-015-0775-0

摘要： The new properties of engineered nanoparticles drive the need for new knowledge on the safety, fate, behavior and biologic effects of these particles on organisms and ecosystems. Titanium dioxide nanoparticles have been used extensively for a wide range of applications, e.g, self-cleaning surface coatings, solar cells, water treatment agents, topical sunscreens. Within this scenario increased environmental exposure can be expected but data on the ecotoxicological evaluation of nanoparticles are still scarce. The main purpose of this work was the evaluation of effects of TiO nanoparticles in several organisms, covering different trophic levels, using a battery of aquatic assays. Using fish as a vertebrate model organism tissue histological and ultrastructural observations and the stress enzyme activity were also studied. TiO nanoparticles (Aeroxide® P25), two phase composition of anatase (65%) and rutile (35%) with an average particle size value of 27.6±11 nm were used. Results on the EC for the tested aquatic organisms showed toxicity for the bacteria, the algae and the crustacean, being the algae the most sensitive tested organism. The aquatic plant showed no effect on growth. The fish showed no effect on a 21 day survival test, though at a biochemical level the cytosolic Glutathione-S-Transferase total activity, in intestines, showed a general significant decrease ( <0.05) after 14 days of exposure for all tested concentrations. The presence of TiO nanoparticles aggregates were observed in the intestine lumen but their internalization by intestine cells could not be confirmed.

关键词： ecotoxicity     enzymatic analysis     histology     transmission electron microscopy (TEM)     TiO2-nanoparticles    

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TRANSLATING THE MULTI-ACTOR APPROACH TO RESEARCH INTO PRACTICE USING A WORKSHOP APPROACH FOCUSING ON

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 460-473 doi: 10.15302/J-FASE-2021416

摘要：

The EIP-Agri multiactor approach was exemplified during a 3-day workshop with 63 project participants from the EU H2020 funded project “Redesigning European cropping systems based on species MIXtures”. The objective was to share firsthand experience of participatory research among researchers who were mostly not familiar with this approach. Workshop participants were divided into smaller multidisciplinary groups and given the opportunity to interact with representatives from eight actor positions in the value chain of the agrifood cooperative Terrena located in Western France. The four stages of the workshop were: (1) key actor interviews, (2) sharing proposed solutions for overcoming barriers, and (3) developing possible interdisciplinary concepts. Expressions of frustration were recorded serving both as a motivation for group members to become more aware of the scientific concerns and practices of their colleagues, as well as a recognition that some researchers have better skills integrating qualitative approaches than others. Nevertheless, the workshop format was an effective way to gain a common understanding of the pertinent issues that need to be addressed to meet overall multiactor-approach objectives. Working with the actor networks was identified and emphasized as a means to overcome existing barriers between academia and practice in order to coproduce a shared vision of the benefits of species mixture benefits.

 

关键词： agroecology     codesign     intercropping     knowledge sharing     participatory methods    

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Comparison of surgical indications for hysterectomy by age and approach in 4653 Chinese women

null

《医学前沿（英文）》 2014年 第8卷 第4期   页码 464-470 doi: 10.1007/s11684-014-0338-y

摘要：

Approximately one million hysterectomies are performed each year in China. However, national data regarding the indications and the surgical approaches for hysterectomy are lacking. The aim of this study was to examine the surgical indications for hysterectomy in different age groups and the relative merits of different surgical approaches for hysterectomy in Chinese women. Clinical data from 4653 cases of hysterectomy performed in Tongji Hospital from 2004 to 2009 were analysed. Hysterectomy was most commonly performed among women aged 40--49 years (2299; 49.4%). Overall, colporrhagia and abdominal pain were the two most common indications for hysterectomy. The most common indications by age groups were as follows: malignant ovarian tumour,<20 years; malignant uterine tumour, 20--29 and 30--39 years; uterine myoma, 40--49 and 50--59 years; and uterine prolapse, 60--69 and>70 years. The proportion of malignant aetiology also varied by age, being the highest in women aged<20 years (75.0%) and the lowest in those aged 40--49 years (19.9%). Approximately 35% women who had hysterectomies also had concomitant bilateral oophorectomy. The lowest rate of oophorectomy occurred in women aged 30--39 years (15.8%), whereas the highest rate was in those aged 50--59 years (75.9%). The abdominal surgical approach was used in 84% of all hysterectomies. Surgeries using the vaginal approach required a significantly shorter operating time (118 min average) than all other approaches (P<0.05). Both the amount of bleeding and the blood transfusion volume required were smaller in vaginal approaches, with no significant differences between the others. The surgical approaches used were also related to the scope of surgery. Both the surgical indications and the rates of bilateral oophorectomy varied by age. In terms of both operating time and the amount of bleeding and blood transfusion volume required, the vaginal approach was superior to all other surgical approaches.

关键词： hysterectomy     surgical indications     surgical approach     bilateral oophorectomy    

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Hierarchical approach for fatigue cracking performance evaluation in asphalt pavements

Ibrahim ONIFADE, Yared DINEGDAE, Björn BIRGISSON

《结构与土木工程前沿（英文）》 2017年 第11卷 第3期   页码 257-269 doi: 10.1007/s11709-017-0410-1

摘要： In this paper, a hierarchical approach is proposed for the evaluation of fatigue cracking in asphalt concrete pavements considering three different levels of complexities in the representation of the material behaviour, design parameters characterization and the determination of the pavement response as well as damage computation. Based on the developed hierarchical approach, three damage computation levels are identified and proposed. The levels of fatigue damage analysis provides pavement engineers a variety of tools that can be used for pavement analysis depending on the availability of data, required level of prediction accuracy and computational power at their disposal. The hierarchical approach also provides a systematic approach for the understanding of the fundamental mechanisms of pavement deterioration, the elimination of the empiricism associated with pavement design today and the transition towards the use of sound principles of mechanics in pavement analysis and design.

关键词： fatigue cracking     energy based     crack initiation     mechanistic approach     pavement analysis    

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Critical flow-storm approach to total maximum daily load (TMDL) development: an analytical conceptual

Zhang Harry, Yu Shaw

《环境科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 267-273 doi: 10.1007/s11783-008-0058-0

摘要： One of the key challenges in the total maximum daily load (TMDL) development process is how to define the critical condition for a receiving waterbody. The main concern in using a continuous simulation approach is the absence of any guarantee that the most critical condition will be captured during the selected representative hydrologic period, given the scarcity of long-term continuous data. The objectives of this paper are to clearly address the critical condition in the TMDL development process and to compare continuous and event-based approaches in defining critical condition during TMDL development for a waterbody impacted by both point and nonpoint source pollution. A practical, event-based critical flow-storm (CFS) approach was developed to explicitly addresses the critical condition as a combination of a low stream flow and a storm event of a selected magnitude, both having certain frequencies of occurrence. This paper illustrated the CFS concept and provided its theoretical basis using a derived analytical conceptual model. The CFS approach clearly defined a critical condition, obtained reasonable results and could be considered as an alternative method in TMDL development.

关键词： representative hydrologic     occurrence     simulation approach     scarcity     alternative    

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Promising approach for preparing metallic single-atom catalysts: electrochemical deposition

《能源前沿（英文）》 2022年 第16卷 第4期   页码 537-541 doi: 10.1007/s11708-022-0837-5

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标题 作者 时间 类型 操作

Seepage failure by heave in sheeted excavation pits constructed in stratified cohesionless soils

Serdar KOLTUK, Jie SONG, Recep IYISAN, Rafig AZZAM

期刊论文

Governance approach to China’s environmental challenges: Towards a theoretical synthesis

QI Ye, XUE Lan, ZHANG Lingyun

期刊论文

Simultaneous harvesting and cell disruption of microalgae using ozone bubbles: optimization and characterization study for biodiesel production

Lim, Peck L. Kiew, Steven Lim, Siti S. Rosli, Chung Y. Wong, Pau L. Show, Keat T. Lee

期刊论文

A novel approach for remanufacturing process planning considering uncertain and fuzzy information

期刊论文

Optimization of WEDM process of pure titanium with multiple performance characteristics using Taguchi’sDOE approach and utility concept

Rupesh CHALISGAONKAR, Jatinder KUMAR

期刊论文

RePizer：一种软件需求排序架构

Saif Ur Rehman KHAN,Sai Peck LEE,Mohammad DABBAGH1,Muhammad TAHIR,Muzafar KHAN,Muhammad ARIF

期刊论文

A Bayesian modeling approach to bi-directional pedestrian flows in carnival events

S. Q. XIE, S. C. WONG, William H. K. LAM

期刊论文

A new and best approach for early detection of rotor and stator faults in induction motors coupled to

Abderrahim ALLAL,Boukhemis CHETATE

期刊论文

One-dimensional consolidation of over-consolidated soil under time-dependent loading

XIE Kanghe, WANG Kun, CHEN Guohong, HU Anfeng

期刊论文

A multi-integrated approach on toxicity effects of engineered TiO

PAIXÃO,Liliana MOITA,Luis SILVA,Mário S.

期刊论文

TRANSLATING THE MULTI-ACTOR APPROACH TO RESEARCH INTO PRACTICE USING A WORKSHOP APPROACH FOCUSING ON

期刊论文

Comparison of surgical indications for hysterectomy by age and approach in 4653 Chinese women

null

期刊论文

Hierarchical approach for fatigue cracking performance evaluation in asphalt pavements

Ibrahim ONIFADE, Yared DINEGDAE, Björn BIRGISSON

期刊论文

Critical flow-storm approach to total maximum daily load (TMDL) development: an analytical conceptual

Zhang Harry, Yu Shaw

期刊论文

Promising approach for preparing metallic single-atom catalysts: electrochemical deposition

期刊论文