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A Building Information Modeling-Life Cycle Cost Analysis Integrated Model to Enhance Decisions Related to the Selection of Construction Methods at the Conceptual Design Stage of Buildings
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作者 Nkechi McNeil-Ayuk Ahmad Jrade 《Open Journal of Civil Engineering》 2024年第3期277-304,共28页
Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to ... Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to perform real-time evaluations to explore various design options. However, when integrated with LCCA, BIM provides a comprehensive economic perspective that helps stakeholders understand the long-term financial implications of design decisions. This study presents a methodology for developing a model that seamlessly integrates BIM and LCCA during the conceptual design stage of buildings. This integration allows for a comprehensive evaluation and analysis of the design process, ensuring that the development aligns with the principles of low carbon emissions by employing modular construction, 3D concrete printing methods, and different building design alternatives. The model considers the initial construction costs in addition to all the long-term operational, maintenance, and salvage values. It combines various tools and data through different modules, including energy analysis, Life Cycle Assessment (LCA), and Life Cycle Cost Analysis (LCCA) to execute a comprehensive assessment of the financial implications of a specific design option throughout the lifecycle of building projects. The development of the said model and its implementation involves the creation of a new plug-in for the BIM tool (i.e., Autodesk Revit) to enhance its functionalities and capabilities in forecasting the life-cycle costs of buildings in addition to generating associated cash flows, creating scenarios, and sensitivity analyses in an automatic manner. This model empowers designers to evaluate and justify their initial investments while designing and selecting potential construction methods for buildings, and enabling stakeholders to make informed decisions by assessing different design alternatives based on long-term financial considerations during the early stages of design. 展开更多
关键词 Life cycle Cost analysis (LCCA) Building Information Modeling (BIM) Cost Decision Modular Construction and 3D Concrete Printing
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A Novel Three-parameter Flow Cytometric Analysis for Cell Cycle
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作者 冯永东 陶德定 +5 位作者 覃吉超 高纯 申漫里 冷艳 余源 龚建平 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第2期76-82,共7页
To set up a three-parameter method for cell cycle analysis by two-laser flowcy-tometer, which can detect two types of cyclin plus DNA content in one measurement, and thatanalyze unscheduled expression of cyclins. Meth... To set up a three-parameter method for cell cycle analysis by two-laser flowcy-tometer, which can detect two types of cyclin plus DNA content in one measurement, and thatanalyze unscheduled expression of cyclins. Methods: Three-color fluorescence was used for analysisof two types of cyclins and DNA content simultaneously in individual cells by two-laser flowcytometry. MOLT-4 cells were used to study the expression of major cyclins in mammalian cells. ATriton-X100 permeabilization procedure was optimized for detection of two types of cyclins. Onecyclin was stained directly with a FITC-conjugated monoclonal antibody (mAb), and the other,indirectly with RPE-Cy5-conjugated secondary antibody, while DNA was stained with the fluorochromeDAPI. mAMSA and mimosine treated MOLT-4 cells were used to test this three-parameter method.Results: Permeabilization with 0.5% Triton-XlOO in PBS containing 1% BSA for 5 min on ice providedoptimal conditions for the simultaneous labelling of two cyclins plus DNA in single cells. It wasfound that the emission spectrum of the three dyes (DAPI, FITC and RPE-Cy5) could be measured withno compensation. Based on cyclinA/cyclinE/DNA flow cytometric analysis, asynchronously growingMOLT-4 cells could be divided into 6 compartments (G1o, G1e, G1l, S, G2, and M) simultaneously,allowing for analysis of cell cycle phase specific perturbations without the necessity of cellsynchronization. Unscheduled cyclin B1 expression was observed in G1 cells treated with mimosine andcyclin E in G2 cells treated with mAMSA. We found that unscheduled cyclin expression paralleledexpected cyclin expression. Conclusion: Thus, three-color FCM analysis of cells may not only beapplied to measure unscheduled vs. expected cyclin expression but may also be used to estimate thefraction of cycling cells in up to 6 cell populations. 展开更多
关键词 cell cycle flow cytometry cyclIN three-parameter analysis
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Comparative analysis of perpetual pavement structures based on pavement performance and life cycle cost 被引量:3
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作者 朱玉琴 倪富健 顾兴宇 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期84-87,共4页
Pavement performance and economic efficiency are researched on the perpetual test pavement of Yijiang-Suzhou Express Highway in Jiangsu province, China. Test sections were continuously monitored. The conditions and de... Pavement performance and economic efficiency are researched on the perpetual test pavement of Yijiang-Suzhou Express Highway in Jiangsu province, China. Test sections were continuously monitored. The conditions and developing laws of deflection, rutting and cracking are compared among the perpetual pavement with the rich binder layer (RBL), the perpetual pavement without the RBL, and the conventional semi-rigid asphalt pavement in the past eight years after opening for traffic. Economical evaluation is conducted via life cycle cost analysis (LCCA). Based on the performance comparison and LCCA analysis, sections with the RBL have good crack resistance, but they are not very satisfactory in the aspect of permanent deformation; the conventional semi-rigid asphalt pavement is the least economic one due to requiring more frequent maintenance. Research results show that the perpetual pavement without RBL is a more appropriate structure for the test site. 展开更多
关键词 perpetual pavement rich binder layer pavementperformance life cycle cost analysis
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Review of energy consumption research for papermaking industry based on life cycle analysis 被引量:6
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作者 Yi Man Yulin Han +1 位作者 Jigeng Li Mengna Hong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第7期1543-1553,共11页
Papermaking industry is a high-energy-consuming industry with long supply chain.The growth of paper product demand further intensifies the need of energy consumption.Energy saving through the full supply chain has bec... Papermaking industry is a high-energy-consuming industry with long supply chain.The growth of paper product demand further intensifies the need of energy consumption.Energy saving through the full supply chain has become a focal point for long-term sustainable development of the papermaking industry.This paper reviews the advances in life cycle analysis for the papermaking industry in recent years.All the stages from the full supply chain are involved to give a panoramic overview of the papermaking industry.The object of this paper is to provide scientific basis to industry and decision-makers with profound understanding of the energy consumption and energy saving potential in a life cycle perspective. 展开更多
关键词 Life cycle analysis PULP PAPERMAKING ENERGY CONSUMPTION ENERGY SAVING
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Thermodynamic analysis and combined cycle research on recoverable pressure energy in natural gas pipeline 被引量:2
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作者 郑斌 刘俊德 《Journal of Beijing Institute of Technology》 EI CAS 2011年第1期65-70,共6页
Current research and ways of capturing mechanical energy are discussed in this paper. By the aid of the comprehensive thermodynamic analysis and Aspen simulation tool, the amount of a vailable work that can be produc... Current research and ways of capturing mechanical energy are discussed in this paper. By the aid of the comprehensive thermodynamic analysis and Aspen simulation tool, the amount of a vailable work that can be produced from capturing the pressure energy has been calculated. Based on the comprehensive thermodynamic analysis, two systems have been proposed to capture pressure energy of natural gas to generate electricity. In this study, the expression of exergy is given which can be used in evaluating purposes. A problem with this multidisciplinary study is the complicated boundary condition. In conclusion, a technical prospect on recoverable natural gas pressure energy has been presented based on total energy system theory. 展开更多
关键词 natural gas pressure energy thermodynamic analysis exergy analysis power genera-tion combined cycle total energy system
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RELIABILITY ANALYSIS FOR AN AERO ENGINE TURBINE DISK UNDER LOW CYCLE FATIGUE CONDITION 被引量:2
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作者 C.L.Liu Z.Z.Lü Y.L.Xu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第4期514-520,共7页
Reliability analysis methods based on the linear damage accumulation law (LDAL) and load-life interference model are studied in this paper. According to the equal probability rule, the equivalent loads are derived, an... Reliability analysis methods based on the linear damage accumulation law (LDAL) and load-life interference model are studied in this paper. According to the equal probability rule, the equivalent loads are derived, and the reliability analysis method based on load-life interference model and recurrence formula is constructed. In conjunction with finite element analysis (FEA) program, the reliability of an aero engine turbine disk under low cycle fatigue (LCF) condition has been analyzed. The results show the turbine disk is safety and the above reliability analysis methods are feasible. 展开更多
关键词 low cycle fatigue life reliability analysis load-life interference model recurrence method aero engine turbine disk
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Shot noise analysis on corrosion behavior of zinc alloy (ZnAl4Cul) under dry-wet cycles 被引量:3
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作者 CHEN An-na CAO Fa-he +4 位作者 LIU Wen-juan ZHENG Li-yun ZHANG Zhao ZHANG Jian-qing CAO Chu-nan 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第1期228-240,共13页
The corrosion behaviors of zinc alloy (ZnAl4Cul) in 3.5% (mass fraction) NaCl, 7.3% (mass fraction) Na2SO4 and simulated acid rain solutions were investigated using electrochemical measurements. The potential no... The corrosion behaviors of zinc alloy (ZnAl4Cul) in 3.5% (mass fraction) NaCl, 7.3% (mass fraction) Na2SO4 and simulated acid rain solutions were investigated using electrochemical measurements. The potential noise during dry-wet cycle was monitored and analyzed by fast Fourier transform (FFT), fast wavelet transform (FWT), shot noise theory and stochastic theory. Cumulative probability curves of event frequency fn indicate that the corrosion events in the dry cycles are greater than those in the wet cycles. Uniform corrosion was observed in the NaCl solution compared with more localized corrosion in the Na2SO4 solution, which is evidenced by FWT and SEM. Conditional events generation rate r(t) for diffusion controlled reactions decreases with increasing the time. r(t) values for uniform corrosion and diffusion controlled process are the largest in the wet cycle in 3.5% NaCl solution. The values of r(t) for pitting corrosion in Na2SO4 solution are observed to become large during spraying periods, and r(t) for pitting corrosion has the largest value in the Na2SO4 solution. The intergranular corrosion of zinc is serious in simulated acid rain solution. 展开更多
关键词 electrochemical noise shot noise analysis dry-wet cycle zinc alloy
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Performance comparison and analysis of a combined power and cooling system based on organic Rankine cycle 被引量:2
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作者 王志奇 周奇遇 +2 位作者 夏小霞 刘斌 张欣 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期353-359,共7页
A novel power and cooling system combined system which coupled organic Rankine cycle(ORC) with vapor compression refrigeration cycle(VCRC) was proposed. R245 fa and butane were selected as the working fluid for the po... A novel power and cooling system combined system which coupled organic Rankine cycle(ORC) with vapor compression refrigeration cycle(VCRC) was proposed. R245 fa and butane were selected as the working fluid for the power and refrigeration cycle, respectively. A performance comparison and analysis for the combined system was presented. The results show that dual-pressure ORC-VCRC system can achieve an increase of 7.1% in thermal efficiency and 6.7% in exergy efficiency than that of basic ORC-VCRC. Intermediate pressure is a key parameter to both net power and exergy efficiency of dual-pressure ORC-VCRC system. Combined system can produce maximum net power and exergy efficiency at 0.85 MPa for intermediate pressure and 2.4 MPa for high pressure, respectively. However, superheated temperature at expander inlet has little impact on the two indicators. It can achieve higher overall COP, net power and exergy efficiency at smaller difference between condensation temperature and evaporation temperature of VCRC. 展开更多
关键词 dual-pressure organic Rankine cycle vapor compression refrigeration waste heat performance analysis
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Techno-Economic Analysis and Life Cycle Assessment for the Typical Intermediate Crude Refining Scheme in China 被引量:2
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作者 Zhou Xin Yan Hao +4 位作者 Feng Xiang Zhao Hui Liu Yibin Chen Xiaobo Yang Chaohe 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第4期35-45,共11页
The integration of refinery and petrochemical units(IRPUs)has become an inevitable choice for the sustainable development of petrochemical industry.The utilization efficiency of petroleum resources could be improved o... The integration of refinery and petrochemical units(IRPUs)has become an inevitable choice for the sustainable development of petrochemical industry.The utilization efficiency of petroleum resources could be improved obviously through IRPUs.However,integrating economic and environmental impacts into the model of IRPUs is still a grand challenge.Herein,a model called TEA-GHG-OPWM(Techno-Economic Analysis and GreenHouse Gases Oriented Plant-Wide Model)has been established on Aspen HYSYSTM platform to calculate the energy consumption,the technoeconomic performance,and the GHG emissions for two different kinds of schemes,viz,:VRHCU(Vacuum Residue Hydrocracking Unit)and VRDS-RFCC(Vacuum Residue Desulfurization and Residue Fluid Catalytic Cracking).Furthermore,a novel processing pathway named VGOHDT-HTMP-DC(Vacuum Gas Oil Hydrotreating,Hydrogenation and TMP coupling process and Delayed Coking)has also been developed to find methods to improve the economic performance based on a ten-million-CNY output value(TMYOV)and a reduced GHG emissions.Our results demonstrate that VRHCRU could consume more energy and emit more GHG(877.11 t of CO2 eq·TMYOV^-1·h^-1)than VRDS-RFCC(817.03 t of CO2 eq·TMYOV^-1·h^-1)and VGOHDT-HTMP-DC(721.96 t of CO2 eq·TMYOV^-1·h^-1),while obtaining a higher mass yield of petrochemicals.The VGOHDT-HTMP-DC process exhibits the lowest feedstock consumption,hydrogen consumption,energy consumption,and GHG emissions,indicating that VGOHDT-HTMP-DC has both well economic and environmentally friendly performance. 展开更多
关键词 techno-economic analysis life cycle assessment integration of refinery and petrochemical units intermediate base crude oil process simulation
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Life cycle cost analysis of new FRP based solar parabolic trough collector hot water generation system 被引量:1
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作者 A. VALAN ARASU T. SORNAKUMAR 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第3期416-422,共7页
Parabolic trough collectors (PTCs) are employed for a variety of applications including steam generation and hot water generation. This paper deals with the experimental results and an economic analysis of a new fib... Parabolic trough collectors (PTCs) are employed for a variety of applications including steam generation and hot water generation. This paper deals with the experimental results and an economic analysis of a new fibre reinforced plastic (FRP) based solar PTC with an embedded electronic controlled tracking system designed and developed for hot water generation in a restaurant in Madurai, India. The new collector performance has been tested according to ASHRAE Standard 93 (1986). The performance of a new PTC hot water generation system with a well mixed hot water storage tank is investigated by a series of extensive tests over ten months period. The average maximum storage tank water temperature observed was 74.91℃, when no energy is withdrawn from the tank to the load during the collection period. The total cost of the new economic FRP based solar PTC for hot water generation with an embedded electronic controlled tracking system is Rs. 25000 (US$ 573) only. In the present work, life cycle savings (LCS) method is employed for a detailed economic analysis of the PTC system. A computer program is used as a tool for the economic analysis. The present worth of life cycle solar savings is evaluated for the new solar PTC hot water generation system that replaces an existing electric water heating system in the restaurant and attains a value of Rs. 23171.66 after 15 years, which is a significant saving. The LCS method and the MATLAB computer simulation program presented in this paper can be used to estimate the LCS of other renewable energy systems. 展开更多
关键词 Economic analysis Life cycle savings Life cycle cost (LCS) Parabolic trough collector (PTC) Solar water heating system (SWHS)
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Parameter fitting of constitutive model and FEM analysis of solder joint thermal cycle reliability for lead-free solder Sn-3.5Ag 被引量:1
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作者 周萍 胡炳亭 +1 位作者 周孑民 杨莺 《Journal of Central South University》 SCIE EI CAS 2009年第3期339-343,共5页
The experimental tests of tensile for lead-flee solder Sn-3.5Ag were performed for the general work temperatures range from 11 to 90 ℃ and strain rate range from 5 × 10^-5 to 2 × 10^-2s^-1, and its stress--... The experimental tests of tensile for lead-flee solder Sn-3.5Ag were performed for the general work temperatures range from 11 to 90 ℃ and strain rate range from 5 × 10^-5 to 2 × 10^-2s^-1, and its stress--strain curves were compared to those of solder Sn-37Pb. The parameters in Anand model for solder Sn-3.5Ag were fitted based on experimental data and nonlinear fitting method, and its validity was checked by means of experimental data. Furthermore, the Anand model was used in the FEM analysis to evaluate solder joint thermal cycle reliability. The results show that solder Sn-3.5Ag has a better creep resistance than solder Sn-37Pb. The maximum stress is located at the upper right comer of the outmost solder joint from the symmetric center, and thermal fatigue life is predicted to be 3.796 × 10^4 cycles under the calculated conditions. 展开更多
关键词 lead free solder Sn-3.5Ag alloy Sn-37Pb alloy constitutive model TENSILE FEM analysis thermal cycle reliability
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PROBABILISTIC METHODOLOGY OF LOW CYCLE FATIGUE ANALYSIS 被引量:1
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作者 JinHui WangJinnuo WangLibin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第4期356-358,366,共4页
The cyclic stress-strain responses (CSSR), Neuber's rule (NR) and cyclic strain-life relation (CSLR) are treated as probabilistic curves in local stress and strain method of low cycle fatigue analysis. The randomn... The cyclic stress-strain responses (CSSR), Neuber's rule (NR) and cyclic strain-life relation (CSLR) are treated as probabilistic curves in local stress and strain method of low cycle fatigue analysis. The randomness of loading and the theory of fatigue damage accumulation (TOFDA) are considered. The probabilistic analysis of local stress, local strain and fatigue life are constructed based on the first-order Taylor's series expansions. Through this method proposed fatigue reliability analysis can be accomplished. 展开更多
关键词 Low cycle fatigue Local stress and strain method Probabilistic analysis Fatigue reliability
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Benefit analysis and contribution prediction of engine remanufacturing to cycle economy
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作者 刘世参 史佩京 +2 位作者 徐滨士 邢忠 谢建军 《Journal of Central South University》 SCIE EI CAS 2005年第S2期25-29,共5页
The first automobile engine remanufacture company in China, Jinan Fuqiang Power Co, Ltd, was introduced. The engine remanufacturing technological process of this company was described. The benefit statistic of remanuf... The first automobile engine remanufacture company in China, Jinan Fuqiang Power Co, Ltd, was introduced. The engine remanufacturing technological process of this company was described. The benefit statistic of remanufacturing 10000 Styer engines were analyzed, and the contribution of engine remanufacturing to cycle economy was predicted. The results show that remanufacturing engineering could use the maximal additional values of obsolete engines, and make contributions to materials conservation, capital saving, energy conservation and environment protection. 10000 engines are supposed to be remanufactured per year, the following benefits would be obtained: reclaiming additional values of RMB3.23 hundred million, saving metallic materials about 7.65 thousand tons, saving energy of 16 million kilowatt-hours, reducing emission of CO2 about 11.3[CD*2]15.3 thousand tons, and providing employment for 500 persons. According to the survey and analysis, tremendous benefits will be gained by the year of 2020. For example, reclaiming additional values per year of 1424[CD*2]2236 hundred million RMB, saving energy per year of 60[CD*2]90 hundred million kilowatt-hours, reducing emission of CO2 about 6.67[CD*2]9.69 million tons. It can be deduced that developing remanufacturing will play an important role in enriching the cycle economy and accelerating the development of national economy. 展开更多
关键词 engine REMANUFACTURING cycle ECONOMY BENEFIT analysis CONTRIBUTION PREDICTION
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Uncertainty in life cycle economical analysis of cassava-based ethanol fuel
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作者 冷如波 戴杜 +1 位作者 陈晓军 王成焘 《Journal of Central South University》 SCIE EI CAS 2005年第S2期65-69,共5页
Biomass ethanol fuel is not only renewable but also environmental-friendly. Guangxi Zhuang Autonomous Region is developing the cassava-based ethanol fuel. Economical performance of the project is the key issue. The tr... Biomass ethanol fuel is not only renewable but also environmental-friendly. Guangxi Zhuang Autonomous Region is developing the cassava-based ethanol fuel. Economical performance of the project is the key issue. The traditional life cycle economical analysis is just a static calculation process. Uncertainty is the character of cassava yield, cost of cassava plant, cassava price, tax rate and gasoline price, and the economical performance of the project is determined by these aspects. This study proposes an economical model of cassava-based ethanol fuel. The method of Monte Carol is used to simulate the economical performance. This method conquers the shortage of the traditional way. The results show that cassava-based ethanol fuel can get survived when the tax is exempted. Finally, the study also evaluates the potential of the economical performance. 展开更多
关键词 UNCERTAINTY life cycle economical analysis CASSAVA ETHANOL FUEL
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FACTORIAL ANALYSIS OF ANNUAL EROSION-ACCRETION CYCLES OF TIDAL FLATS IN THE FRONT AREA OF THE SOUTHERN CHANGJIANG RIVER DELTA
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作者 杨世伦 陈祥锋 张正惕 《Chinese Geographical Science》 SCIE CSCD 1998年第1期2-12,共0页
Based on surveyed data from seven coastal sections and the collected data of wind, sea level, tide, nearshore suspended sediment concentration and river flux from adjacent stations, this paper deals with regressive ... Based on surveyed data from seven coastal sections and the collected data of wind, sea level, tide, nearshore suspended sediment concentration and river flux from adjacent stations, this paper deals with regressive correlation between monthly average flat elevation and monthly average figures of the influential factors. All sections except one which is located within the river mouth showed negative correlation between flat elevation and sea level and between flat elevation and tidal range, with correlation coefficients being 0.53- 0.91(-0.77 on the average) in the former condition and 0.56- 0.97 (-0.80 on the average) under the latter. Each of the sections with available suspended sediment concentration (SSC) data shows a positive correlation between flat elevation and SSC, with correlative coefficients being 0.35-0.97 (0.66 on the average). Only two sections (one in the Changjiang River Estuary and the other in the Hangzhou Bay) which are similar to beaches in sediment grain size and slope gradient showed a negative correlation between flat elevation and onshore wind frequency and between flat elevation and average wind velocity, with correlative coefficients being respectively -0.57 and -0.69 (-0.63 on the average) in the former situation and -0.61 and -0.75 (-0.68 on the average) in the latter. Other sections did not show uniform relationship between flat elevation and wind conditions. Due to local marine factors the nearshore SSC in the studied area is negatively correlated with the Changjiang River sediment flux (r=-0.78), which results in false negative correlation between flat elevation and river sediment flux. The paper also gives sediment dynamic and morphodynamic explanation for the above correlations. Sea level rise results in the spread of breaker zone from subtidal area to intertidal area and then increases the intertidal water energy. The larger the tidal range, the stronger the tide currents and the easier for the flat to be eroded. The higher the SSC of flood water, the easier for the sediment to deposit down. Because of correlations among the influential factors, it is difficult to give the prime one which dominates the erosion and accretion processes in tidal flats. 展开更多
关键词 TIDAL flat EROSION ACCRETION cycle the CHANGJIANG River DELTA FACTORIAL analysis
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Statistical Analysis for the Driving Cycle of Beijing's Bus
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作者 王震坡 孙逢春 +1 位作者 王军 孙立清 《Journal of Beijing Institute of Technology》 EI CAS 2004年第4期436-440,共5页
According to the test data of the driving model for Beijing's bus routes, 9 parameters and the actual values of Beijing bus are confirmed to evaluate the driving cycle, 2 ways of establishing driving cycle model a... According to the test data of the driving model for Beijing's bus routes, 9 parameters and the actual values of Beijing bus are confirmed to evaluate the driving cycle, 2 ways of establishing driving cycle model are analyzed, the formula of calculating driving cycle is acquired, and the calculating driving cycle model and the statistical driving cycle model for the buses in Beijing urban areas are set up. This study provides scientific basis for selecting the bus type and confirming the design parameters and the running method in Beijing. 展开更多
关键词 Beijing's bus statistical analysis driving cycle average speed
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Finite element analysis on deformation of high embankment in heavy-haul railway subjected to freeze-thaw cycles
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作者 ChengYi Yu Shuang Tian +2 位作者 Liang Tang XianZhang Ling GuoQing Zhou 《Research in Cold and Arid Regions》 CSCD 2015年第4期421-429,共9页
Finite element simulations are increasingly providing a versatile environment for this topic. In this study, a two-dimensional finite element analysis is conducted to predict the deformation of high embankment in Bazh... Finite element simulations are increasingly providing a versatile environment for this topic. In this study, a two-dimensional finite element analysis is conducted to predict the deformation of high embankment in Bazhun heavy-haul railway, China. A recently developed nonlinear softening-type constitutive model is utilized to model the be- havior of subgrade filling materials subjected to freeze-thaw cycles. For the convenience of practical application, the dynamic loading induced by a vehicle is treated as a quasi-static axle load. The deformation of this embankment with different moisture content under freeze-thaw cycles is compared. The results show that when subjected to the first freeze-thaw cycle, the embankment experienced significant deformation variations. Maximum deformation was usually achieved after the embankment with optimum moisture content experienced six freeze-thaw cycles, however, the em- bankment with moisre content of 8.0% and 9.5% deforms continuously even after experiencing almost ten freeze-thaw cycles. Overall, this study provides a simple nonlinear finite element approach for calculating the deformation of the embankment in changing climate conditions. 展开更多
关键词 DEFORMATION nonlinear finite element analysis freeze-thaw cycles EMBANKMENT heavy-haul railway
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An Application of Wavelet Analysis to Meat Consumption Cycles 被引量:1
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作者 Marija Banovic Luis Catela Nunes Vladan Arsenijevic 《Food and Nutrition Sciences》 2013年第3期252-261,共10页
The existence or nonexistence of changes in meat consumption cycles is critical to meat industry. If the change is existent, there is a need to understand what motivates the change to identify the most appropriate res... The existence or nonexistence of changes in meat consumption cycles is critical to meat industry. If the change is existent, there is a need to understand what motivates the change to identify the most appropriate response. Wavelet analysis is considered here as a promising technique that may lead to a better understanding of characteristic patterns and changes in the meat consumption cycles. 展开更多
关键词 Meat Consumption cycles Wavelet analysis
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Probabilistic Analysis of Life Cycle Cost for Power Transformer
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作者 Jianpeng Bian Xiaoyun Sun +2 位作者 Mingming Wang Haiqing Zheng Hui Xing 《Journal of Power and Energy Engineering》 2014年第4期489-494,共6页
The selection of power transformer is very important to power sector. Most methods are utilized according to the initial cost and don’t consider the synthetical evaluation of economy and technology. Based on previous... The selection of power transformer is very important to power sector. Most methods are utilized according to the initial cost and don’t consider the synthetical evaluation of economy and technology. Based on previous research, this paper addresses a new practical probabilistic life cycle cost model. Then, in order to demonstrate the practicability of probabilistic life cycle cost for the power transformer, illustrative investment alternatives of actual power transformers are discussed. From the result of the numerical investigation, it may be positively stated that the optimum investment alternative for the power transformer based on the probabilistic life cycle cost model proposed in this study will lead to a more rational, economical and effective procedure compared with the conventional method only considering the initial cost. 展开更多
关键词 POWER TRANSFORMER PROBABILISTIC analysis LIFE cycle COST
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Second Law of Thermodynamics Analysis of Transcritical Carbon Dioxide Refrigeration Cycle
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作者 杨俊兰 马一太 +1 位作者 管海清 李敏霞 《Transactions of Tianjin University》 EI CAS 2004年第3期179-183,共5页
In order to identify the locations of irreversible loss within the transcritical carbon dioxide refrigeration cycle with an expansion turbine, a method with respect to the second law of thermodynamics based on exergy ... In order to identify the locations of irreversible loss within the transcritical carbon dioxide refrigeration cycle with an expansion turbine, a method with respect to the second law of thermodynamics based on exergy analysis model is applied. The effects of heat rejection pressures, outlet temperatures of gas cooler and evaporating temperatures on the exergy loss, exergy efficiency and the coefficient of performance (COP) of the expansion turbine cycle are analyzed. It is found that the great percentages of exergy losses take place in the gas cooler and compressor. Moreover, heat rejection pressures, outlet temperatures of gas cooler and evaporating temperatures have strong influence on the exergy efficiency, COP and the exergy loss of each component. The analysis shows that there exists an optimal heat rejection pressure corresponding to the maximum exergy efficiency and COP, respectively. The results are of significance in providing theoretical basis for optimal design and the control of the transcritical carbon dioxide system with an expansion turbine. 展开更多
关键词 carbon dioxide transcritical refrigeration cycle expansion turbine exergy analysis
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