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Changshu textile machinery:Various motion devices show the cost performance
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《China Textile》 2023年第3期82-82,共1页
As a professional manufacturer of shedding devices and machines,Changshu Textile Machinery works Co.,Ltd.has been concentrating on research and development since it successfully developed the first ZED204 electronic d... As a professional manufacturer of shedding devices and machines,Changshu Textile Machinery works Co.,Ltd.has been concentrating on research and development since it successfully developed the first ZED204 electronic dobby in China in 1993.Through technological innovation and process improvement,speed,reliability and cost performance of products have been obviously improved.Dobby,cam and jacquard are suitable for all kinds of mainstream looms in the international market. 展开更多
关键词 cost performance MOTION
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Layered power scheduling optimization of PV hydrogen production system considering performance attenuation of PEMEL 被引量:1
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作者 Yanhui Xu Haowei Chen 《Global Energy Interconnection》 EI CSCD 2023年第6期714-725,共12页
To analyze the additional cost caused by the performance attenuation of a proton exchange membrane electrolyzer(PEMEL)under the fluctuating input of renewable energy,this study proposes an optimization method for powe... To analyze the additional cost caused by the performance attenuation of a proton exchange membrane electrolyzer(PEMEL)under the fluctuating input of renewable energy,this study proposes an optimization method for power scheduling in hydrogen production systems under the scenario of photovoltaic(PV)electrolysis of water.First,voltage and performance attenuation models of the PEMEL are proposed,and the degradation cost of the electrolyzer under a fluctuating input is considered.Then,the calculation of the investment and operating costs of the hydrogen production system for a typical day is based on the life cycle cost.Finally,a layered power scheduling optimization method is proposed to reasonably distribute the power of the electrolyzer and energy storage system in a hydrogen production system.In the up-layer optimization,the PV power absorbed by the hydrogen production system was optimized using MALTAB+Gurobi.In low-layer optimization,the power allocation between the PEMEL and battery energy storage system(BESS)is optimized using a non-dominated sorting genetic algorithm(NSGA-Ⅱ)combined with the firefly algorithm(FA).A better optimization result,characterized by lower degradation and total costs,was obtained using the method proposed in this study.The improved algorithm can search for a better population and obtain optimization results in fewer iterations.As a calculation example,data from a PV power station in northwest China were used for optimization,and the effectiveness and rationality of the proposed optimization method were verified. 展开更多
关键词 PV electrolysis of water Proton exchange membrane electrolyzer performance attenuation Degradation cost Power scheduling optimization
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Realization and Analysis of Good Fuel Economy and Kinetic Performance of a Low-cost Hybrid Electric Vehicle 被引量:7
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作者 WANG Lei ZHANG Jianlong YIN Chengliang ZHANG Yong WU Zhiwei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期774-789,共16页
By using high-power and high-efficiency propulsion systems,current hybrid electric vehicles(HEVs) in market can achieve excellent fuel economy and kinetic performance.However,it is the cost of current HEVs that hind... By using high-power and high-efficiency propulsion systems,current hybrid electric vehicles(HEVs) in market can achieve excellent fuel economy and kinetic performance.However,it is the cost of current HEVs that hinders HEVs coming into widespread use.A novel hybrid electric propulsion system is designed to balance HEV cost and performance for developing markets.A battery/supercapacitor-based hybrid energy storage system(HESS) is used to improve energy conversion efficiency and reduce battery size and cost.An all-in-one-controller(AIOC) which integrates engine electronic control unit(ECU),motor ECU,and HESS management system is developed to save materials and energy,and reduce the influence of distribution parameters on circuit.As for the powertrain configuration,four schemes are presented:belt-driven starter generator(BSG) scheme,four-wheel drive HEV scheme,full HEV scheme,and ranger-extender electric vehicle(EV) scheme.Component selection and parameter matching for the propulsion system are performed,and an energy management strategy is developed based on powertrain configuration and selected components.Forward-facing simulation models are built,comprehending the control strategy based on the optimal engine torque for the low-cost hybrid electric propulsion system.Co-simulation of AVL CRUISE and Matlab/Simulink is presented and the best scheme is selected.The simulation results indicate that,for the best design,fuel consumption in urban driving condition is 4.11 L/(100 km) and 0-50 km/h accelerating time is 10.95 s.The proposed research can realize low-cost concept for HEV while achieving satisfactory fuel economy and kinetic performance,and help to improve commercialization of HEVs. 展开更多
关键词 low-cost hybrid electric vehicle hybrid energy storage system(HESS) fuel economy kinetic performance co-simulation cost and performance tradeoff
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Low cost, high performance supercapacitor electrode using coconut wastes: eco-friendly approach 被引量:1
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作者 Divyashree A. Shoriya Aruni Bt Abdul Manaf +3 位作者 Yallappa S. Chaitra K. Kathyayini N. Gurumurthy Hegde 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第5期880-887,共8页
Low cost, high performance supercapacitor electrodes were fabricated using coconut waste as precursor. Simple one step pyrolysis is adopted to get the spherical shaped particle where lignocellulosic nature of carbon c... Low cost, high performance supercapacitor electrodes were fabricated using coconut waste as precursor. Simple one step pyrolysis is adopted to get the spherical shaped particle where lignocellulosic nature of carbon converts into porous carbon nanospheres. Three types of coconut wastes, namely, coconut fiber(CF), coconut leaves(CL) and coconut stick(CS) have been studied and compared for their application in supercapacitors. Uniform spherical shape with particle size ranging from 30 to 60 nm for leaves and sticks and20 nm for fibers was obtained. The electrochemical properties of the porous carbon nanospheres were studied using cyclic voltammetry(CV), chronopotentiometry(CP) and electrochemical impedance spectroscopy(EIS). The porous carbon nanospheres derived from all the three biowaste samples show good electrochemical performance for supercapacitor application. Porous carbon nanospheres derived from coconut fiber exhibited maximum specific capacitance of 236 F/g followed by coconut stick and coconut leaves with 208 and 116 F/g respectively at a scan rate of 2 m V/s. Further impedance studies showed a charge transfer resistance of 4.9 for the porous carbon nanospheres derived from coconut fiber, while those from coconut leaves and coconut stick exhibited a slightly higher resistance of 6 and14.2, respectively. The simple eco-friendly approach we have demonstrated for synthesizing coconut waste based carbon nanospheres makes them excellent candidates for future, low-cost, energy storage devices. 展开更多
关键词 Low cost Coconut waste BIOWASTE High performance SUPERCAPACITOR Energy storage
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Effects of Replacing Maize with Dioscarea bulbifera Flour on Growth Performance of Broiler Chickens
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作者 Kemmo Kenhagho Arielle Priscila Tchouan Deffo Gilchrist +2 位作者 Ngouana Tadjong Ruben Edie Nounamo Langston Wilfried Kana Jean Raphael 《Open Journal of Animal Sciences》 CAS 2023年第2期217-231,共15页
The present study was designed to evaluate Dioscarea bulbifera flour as potential feed ingredient in broilers diets. For this purpose, 256-day-old Cobb 500 broiler chicks, were divided into 4 groups replicated 4 times... The present study was designed to evaluate Dioscarea bulbifera flour as potential feed ingredient in broilers diets. For this purpose, 256-day-old Cobb 500 broiler chicks, were divided into 4 groups replicated 4 times in a completely randomized design. A control ration (R0) containing maize as the main energy source was compared to three other rations in which 50%, 75% and 100% maize were substituted with Dioscarea bulbifera flour. The main results showed that, the increasing rate of Dioscarea bulbifera flour had no significant (p > 0.05) effect on the digestibility of feed components. Feed intake was higher with 50% and 75% Dioscarea bulbifera flour inclusion levels. As compared to the control ration, a significant (p < 0.05) drop in live weight and weight gain was recorded with 50% substitution while feed conversion ratio increased significantly with increasing level of Dioscarea bulbifera flour in the ration. Dioscarea bulbifera flour induced a linear and significant (p < 0.05) increase in the relative weight of the gizzard, liver and production cost. It was concluded that, substituting 50% maize with Dioscarea bulbifera flour could be a sustainable solution to palliate the growing inflation of maize as animal feed ingredient. However, the incorporation level of Dioscarea bulbifera as feed ingredient in substitution of maize must not exceed 50% at the risk of depreciating growth performance of broilers. 展开更多
关键词 Diocorea bulbifera Growth performance cost of Production BROILERS Maize Substitute
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Study on Generation Cost Prediction Based on Coal Quality and Generating Unit Performance 被引量:6
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作者 ZHONG Wei LIU Chenggang ZHOU Yonggang WU Yanling ZHOU Yi LI Pei 《中国电机工程学报》 EI CSCD 北大核心 2013年第11期I0004-I0004,6,共1页
燃料变化条件下发电成本的预测是火电厂普遍关心的重要课题。分析了影响机组性能及发电电量成本的各种煤质指标,重点研究了基于结构参数及燃烧传热机理的锅炉稳态热力性能分析计算方法,讨论了制粉系统、风机、脱硫和脱硝装置性能随燃... 燃料变化条件下发电成本的预测是火电厂普遍关心的重要课题。分析了影响机组性能及发电电量成本的各种煤质指标,重点研究了基于结构参数及燃烧传热机理的锅炉稳态热力性能分析计算方法,讨论了制粉系统、风机、脱硫和脱硝装置性能随燃料等运行条件的变化关系,最终提出了基于煤质和机组性能分析计算的发电电量成本预测模型并研发了“煤炭选配与机组发电成本预测系统”。该系统在我国某600MW火电厂的实际应用经验表明:提出的电量成本分析预测模型合理,研发的软件系统有助于辅助火电厂的选煤和购煤决策,优化动力配煤方案,从而提高火电厂的运行经济性。 展开更多
关键词 成本预测 发电成本 机组性能 市场化改革 煤质 火电厂 电力 燃料
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A novel model for cost performance evaluation of pulverized coal injected into blast furnace based on effective calorific value 被引量:4
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作者 徐润生 张建良 +3 位作者 左海滨 李克江 宋腾飞 邵久刚 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3990-3998,共9页
The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific... The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific value representing the actual thermal energy provided for blast furnace was proposed. A cost performance evaluation model of coal injection was built up for the optimal selection of various kinds of coal based on effective calorific value. The model contains two indicators: coal effective calorific value which has eight sub-indicators and coal injection cost which includes four sub-indicators. In addition, the calculation principle and application of cost performance evaluation model in a Chinese large-scale iron and steel company were comprehensively introduced. The evaluation results finally confirm that this novel model is of great significance to the optimal selection of blast furnace pulverized coal. 展开更多
关键词 高炉喷吹煤粉 效益评价模型 燃烧热值 成本效益 物理化学反应 大型钢铁企业 燃烧过程 燃烧特性
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The Two-Constant Cost Model and the Estimation of the Cost Performance Evolutions of the Proton Exchange Membrane Fuel Cell Power Generation
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作者 H. F. Zhang P. C. Pei 《Energy and Power Engineering》 2013年第2期1-10,共10页
This paper aims at formulization and overview of the cost performance evolutions of proton exchange membrane (PEM) fuel cell power generation along with load and time. For this purpose, electricity-cost ratio (ECR) is... This paper aims at formulization and overview of the cost performance evolutions of proton exchange membrane (PEM) fuel cell power generation along with load and time. For this purpose, electricity-cost ratio (ECR) is proposed as the measuring parameter for the cost performance and a two-constant cost model is proposed to concisely describe the cost characteristic of the power generation as the opposite of a multi-constant cost model. Combination of the two-constant cost model and the ideal cell model developed recently produces an inclusive ECR equation that has three analytical expressions and thus allows of straight overviews of the cost performance evolutions in the working zones of the cells. The applications to real cells confirm the validity of the equation for operation optimization and technique evaluation of PEM fuel cells. And more insights into the cost performance evolutions are inferred by means of the equation to help promote the commercialization of PEM fuel cells. 展开更多
关键词 FUEL Cell cost performance LIFETIME DEGRADATION Energy Efficiency Operation Optimization
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Discrimination and Estimation of the Maximum Cost Performance of Proton Exchange Membrane Fuel Cell Power Generation with Seven Constants
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作者 H. F. Zhang P. C. Pei 《Energy and Power Engineering》 2013年第2期55-75,共21页
This paper is dedicated to analytical expression of the maximum electricity-cost ratio (M-ECR) point of the proton exchange membrane (PEM) fuel cell power generation as the function of cell constants and cost constant... This paper is dedicated to analytical expression of the maximum electricity-cost ratio (M-ECR) point of the proton exchange membrane (PEM) fuel cell power generation as the function of cell constants and cost constants. That is to formulize the maximum cost performance (MCP) magnitude and the optimal final operating (OFO) location in the working zone based on the five-constant ideal cell model and the two-constant cost model. The issues are well resolved by introducing the concepts of economic voltage and cost factor and describing the movement of the M-ECR point with cost factor. According to mathematical derivations, the movement can be described in the form of MCP and OFO curves. The derivations lead to a complete set of discriminants and criteria of the M-ECR point of PEM fuel cells that theoretically cover all of cell specialties and all of cost specialties. The discriminants and criteria may act as a general tool for the operation optimization of a diversity of PEM fuel cells and the economic viability estimation of the power generation. 展开更多
关键词 Fuel Cell Working Zone ECONOMIC VIABILITY COMMERCIALIZATION cost performance Operation Optimization
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Analysis of Construction Duration and Cost for Public Sector Civil Engineering Projects in Libya
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作者 Tgarid Ali Xiaohui Zhong Utpal Dutta 《Journal of Civil Engineering and Architecture》 2018年第12期838-847,共10页
Public construction project data were analyzed to develop models for the actual construction duration and actual cost. Based on 50 civil engineering projects in Libya from the database of the Great Man-Made River Syst... Public construction project data were analyzed to develop models for the actual construction duration and actual cost. Based on 50 civil engineering projects in Libya from the database of the Great Man-Made River System 1992-2009, the models identified extension as a main factor that affecting both the actual duration and cost of a project, while considering the contract cost and contract duration as fixed for the project. The suitability of each model was confirmed by examining RMSE (root mean squared error), NSE (Nash-Sutcliffe efficiency), and MEF (modeling efficiency factor). The models were validated with data from 17 different projects. The validation of both models demonstrated that models are very practical and accurate. The models are very effective in capturing the uniqueness of Libyan construction industry practice. 展开更多
关键词 PUBLIC PROJECTS CIVIL engineering PROJECTS actual CONSTRUCTION duration actual CONSTRUCTION cost
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An Overview of Performance Characteristics, Experiencesand Trends of Aerospace Engine Bearings Technologies 被引量:26
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作者 Ebert Franz-Josef 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第4期378-384,共7页
In this paper, the operating conditions, technical requirements, performance characteristics, design ideas, application experiences and development trends of aerospace engine bearings, including material technology, i... In this paper, the operating conditions, technical requirements, performance characteristics, design ideas, application experiences and development trends of aerospace engine bearings, including material technology, integration design and reliability, are reviewed. The development history of aerospace engine bearing is recalled briefly at first. Then today's material technologies and the high bearing performances of the bearings obtained through the new materials are introduced, which play important roils in the aeroengine bearing developments. The integration design ideas and practices are explained to indicate its significant advantages and importance to the aerospace engine bearings. And the reliability of the shaft-bearing system is pointed out and treated as the key requirement with goals for both engine and bearing. Finally, as it is believed that the correct design comes from practice, the pre-qualification rig testing conducted by FAG Aerospace GmbH & Co. KG is briefly illustrated as an example. All these lead to the development trends of aerospace engine bearings from different aspects. 展开更多
关键词 aerospace engine bearing performance characteristic material technology integrated bearing design reliability system cost
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How Does ESG Performance Impact Corporate Financing Costs?An Empirical Study in China
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作者 Wei LI Mei MEI +2 位作者 Xiaoyan YU Jiahao WANG Tiangeng (Becky) GENG 《Journal of Systems Science and Information》 CSCD 2024年第2期229-244,共16页
In the background of the green transformation of the economy and society,the ESG performance of enterprises has been paid more and more attention in the investment decision-making.However,previous studies have inadequ... In the background of the green transformation of the economy and society,the ESG performance of enterprises has been paid more and more attention in the investment decision-making.However,previous studies have inadequately explored how the ESG performance affects corporate financing costs.Based on the information asymmetry theory,this paper analyzes the impact mechanism of ESG performance on corporate financing costs.Then,taking 1044 A-share listed companies in2016–2020 as a sample,through the sorting and analysis of ESG report disclosure and rating data,the company’s ESG performance indicators are obtained,and an empirical model is built to test the relationship between ESG performance and corporate financing costs.This paper constructs a panel regression model using ESG rating data and corporate financial data and finds that in the overall sample,the higher the ESG performance,the lower the equity financing cost;The higher the ESG performance,the lower the debt financing cost.In addition,it also discussed the moderating effect of enterprise scale and media attention on the impact of ESG performance on enterprise financing costs.The empirical results show that the influence of company size on ESG performance on financing costs has a moderating effect and a positive moderating effect. 展开更多
关键词 ESG performance financing cost corporate heterogeneity media attention
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Efficient structural seismic performance evaluation method using improved endurance time analysis 被引量:3
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作者 Li Shuang Liu Kun +2 位作者 Liu Xiangyang Zhai Changhai Xie Fengwei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第4期795-809,共15页
Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dyna... Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dynamic analysis (IDA) method or pushover method. The recently developed endurance time (ET) method is another method that uses dynamic pushover excitations, i.e., endurance time acceleration function, to obtain results similar to those obtained by IDA or pushover methods with low computational cost and acceptable accuracy. This study proposes an improvement on the ET method by considering more restrictions for both the elastic and inelastic response spectra in the generation procedure, and by specifying a target duration. Four reinforced concrete frame structures with 4, 8, 12, and 16 stories are adopted to verify the accuracy of the improved method. Comparison of the results obtained by the proposed method, the ET method and the IDA method shows that the improved method has a higher accuracy than the ET method. For evaluation of structural responses under specifi c ground motion intensity, which is typically required in seismic design codes, the results obtained by the proposed method are compared with fi ve commonly used ground motion selection methods, and shows the proposed method provides acceptable accuracy for engineering applications. 展开更多
关键词 SEISMIC performance evaluation ENDURANCE TIME method INELASTIC response spectra target duration
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Effects of Diets with Different Corn-to-Soybean Ratios on Performance of Lactational Rex Rabbits 被引量:1
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作者 SUN Li-na GU Zi-lin LIU Ya-juan LI Su-min 《Animal Husbandry and Feed Science》 CAS 2010年第1期24-26,31,共4页
[ Objective] To study the effects of diets with different com-to-soybean ratios on production performance of lactational Rex rabbits and select the best feed formula. [Method] A total of 80 lactational healthy Rex rab... [ Objective] To study the effects of diets with different com-to-soybean ratios on production performance of lactational Rex rabbits and select the best feed formula. [Method] A total of 80 lactational healthy Rex rabbits (similar age, body weight and delivery time) were randomly divided into five groups, 16 in each group. The Rex rabbits in group I were fed with corn-based meal diet, group II with soybean-based meal diet, group III with the developed corn-soybean meal diet, group IV with corn-soybean meal free diet, and group CK with conventional corn-soybean meal diet. During the lactation period, the changes in the lactation performance, growth rate of baby rabbits, weight and feed costs were observed. [ Result] The lactation performance of mother rabbits and the growth rate of baby rabbits in the experimental groups were similar to that in the control group. The weaning survival rate of the group III was the highest, but it was not significantly higher than that of the control group. The weaning survival rate of the other three groups was lower than that of the control group (P〈0.05). The weight loss of mother rabbits in the group I, II and III was not significantly different from that of the control group, but the weight loss of the group IV was higher than that of the control group ( P 〈 0.01 ). [ Conclusion] Diets with appropriate corn-to-soybean ratios not only reduce feed costs but also give the best feeding effects. 展开更多
关键词 Lactational Rex rabbits Lactation performance Growth rate WEIGHT Feed costs
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Energy and Exergy Analysis, and Thermoeconomic Performance of a BCHP System 被引量:2
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作者 曹家枞 刘凤强 +2 位作者 秦志红 曹双华 张时飞 《Journal of Donghua University(English Edition)》 EI CAS 2004年第5期36-42,共7页
Building cooling, heating and power (BCHP) systems should play an important role in achieving the goals of energy efficient use and environment protection in China. It will make big sense when this type of system show... Building cooling, heating and power (BCHP) systems should play an important role in achieving the goals of energy efficient use and environment protection in China. It will make big sense when this type of system shows a good performance energetically and economically. An on-site BCHP system being the first in the country was installed and put to use five years ago. As the first step to evaluate the project, computations were made based on thermodynamic and thermoeconomic theories to evaluate the system on full load and off-design conditions in summer. Discussion and analyses are made mainly in terms of exergetic efficiency and costs of unit amount of useful exergy produced in this paper. 展开更多
关键词 BCHP系统 放射热能分析 成本分摊 环境保护
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Making Sense of Hospital Project MisPerformance: Over Budget, Late, Time and Time Again—Why? And What Can Be Done About It?
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作者 Peter E.D.Love Lavagnon A.Ika 《Engineering》 SCIE EI CAS 2022年第5期183-201,共19页
Hospital projects worldwide often experience misperformance,showing a tendency to exceed their estimated cost,miss their deadline,suffer quality problems,and yield benefit shortfalls.Considering this ubiquitous proble... Hospital projects worldwide often experience misperformance,showing a tendency to exceed their estimated cost,miss their deadline,suffer quality problems,and yield benefit shortfalls.Considering this ubiquitous problem,this paper aims to make sense of this phenomenon by addressing the following research question:How can we make sense of hospital project misperformance,and what can be done to mitigate its occurrence?We use an illustrative case study approach and the analytical lens of sense-making to examine the misperformance of three mega-hospital projects.Our research reveals issues such as scope changes,an inability to adapt and respond to risk and uncertainty,ineffectual project management and governance,and optimism bias,which combine to impact project performance adversely.We suggest that the two prominent theoretical perspectives dominating the literature in this field fall short of adequately explaining hospital project misperformance.We provide suggestions for improving the procurement process of hospitals and submit there is a need to develop a robust and balanced theory of project misperformance. 展开更多
关键词 cost Hospital Optimism bias Procurement Project management performance Sense-making
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Use of Stone Dust in the Design of High Performance Concrete
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作者 Joffrey Cheruiyot Sylvester Ochieng Abuodha Charles Kabubo 《Open Journal of Civil Engineering》 2014年第3期229-239,共11页
This research evaluated the suitability of stone dust in the design and production of High Perfor-mance Concrete (HPC). HPC mix was designed, tested, costed and a comparison of concrete classes used in the market (Cla... This research evaluated the suitability of stone dust in the design and production of High Perfor-mance Concrete (HPC). HPC mix was designed, tested, costed and a comparison of concrete classes used in the market (Class 25, 30 and 35) done using Cost Benefit Analysis (CBA). The cost benefit was analyzed using Internal Rate of Return (IRR) and Net Present Value (NPV). Laboratory tests established the properties concrete obtained from the design mix. Compressive strength, slump, and modulus of elasticity were tested and analyzed. Structural analysis using BS 8110 was done for a 10 storey office building to establish the structural member sizes. Members obtained from concrete Classes 25, 30, 35 and the new compressive strengths from HPC (Class 80) were obtained and compared. Analysis was done for structural members’ sizes and area freed as a result of de-signing with HPC as well as the steel reinforcement used. To justify the initial cost of HPC if ado- pted, the Cost Benefit Analysis (CBA) was used to estimate increased costs versus income resulting from increased let table space created. The minimum class of concrete used in design was limited to Class 25 N/mm2. The research shows that it is possible to manufacture high strength concrete using locally available stone dust. The stone dust sampled from Mlolongo quarries achieved a characteristic strength of 86.7 N/mm2 at a water cement ratio of 0.32. With the results structural analysis of a 10 storey office structures with columns spaced at 8 meters center to center was de-signed using the four classes and results compared. There was a reduction of columns from 1.2 m wide to 0.65 m wide (over 45%) when concrete class changes from Class 25 to Class 80 creating over 3% of the total space area per floor. Cost benefit analysis using Net Present Value (NPV) and Internal Rate of Return (IRR) presented business case for the use of HPC. With Class 80, the IRR was at 3% and NPV being 8% of the total initial investment. The steel reinforcement increased by 8.64% using Class 30, 11.68% using Class 35 and reduced by 8.37% at Class 80. Further analysis needs to be done to understand the trend of steel reinforcement keeping all the member sizes the same. In this study the member sizes were optimized based on the steel reinforcement and serviceability. This paper provides useful information to design Engineers and Architects and inform future design of multi storey structures. 展开更多
关键词 High performance Concrete (HPC) Locally Produced QUARRY DUST Properties cost BENEFIT Analysis (CBA) Net Present Value (NPV) Internal Rate of Return (IRR)
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Assessment of Performance Based Road Maintenance Practices in Nepal
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作者 Abhiman Das Mulmi 《Open Journal of Civil Engineering》 2016年第2期225-241,共17页
Roads are the major asset of any country and to conserve them maintenance is essential. The delay of maintenance works can lead the road in the stage of expensive rehabilitation and reconstruction. In Nepal, Departmen... Roads are the major asset of any country and to conserve them maintenance is essential. The delay of maintenance works can lead the road in the stage of expensive rehabilitation and reconstruction. In Nepal, Department of Roads (DoR) is responsible for maintenance of strategic roads of country. The maintenance practice of the road under Department of Road is predominantly based on Strengthen Maintenance Division Process where several maintenance activities like Routine maintenance, Recurrent Maintenance, Periodic Maintenance and Emergency Maintenance are planned and carried out. The maintenance work is based on traditional quantity and unit price based short term maintenance contracts, where maintenance of physical works is outsourced. Client demands the contractor what work is to be done, when to be do it and the extent of the work. The contractor is paid on the basis of a defined output or quantity accomplished, and the schedule of the rates. DoR engineers required full time supervision of work. Pilot based performance based maintenance practice of road started in Nepal in 2003. The study assesses performance road maintenance practices of road maintenance in Nepal on the basis of the framework of cost efficiency, level of service effectiveness and quality of service. The study concluded that implementation of Performance Based Maintenance Contract (PBMC) was not successful in Nepal as Road Asset condition was not maintained to performance standard. One of the reasons is the weak service delivery of contractor alongside weak contract enforcement from the road agency. 展开更多
关键词 Road Maintenance performance Based Maintenance cost Efficiency Contract Management
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Growth Performance, Feed Conversion Ratio and Economics of Production of Native and Crossbred (Local x Holstein Friesian) Bulls for Fattening under Different Improved Feeding
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作者 Mohammad Abu Bakkur Siddque Nathu Ram Sarker +2 位作者 Mohammad Abdul Hamid Mohammad Nurul Amin Monira Sultana 《Journal of Agricultural Science and Technology(A)》 2015年第9期770-781,共12页
关键词 杂种公牛 饲料转化率 牛肉生产 生长性能 经济学 杂交 平均日增重 干物质采食量
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Study on Model for Assessment of Quality Management Performance of Coal Preparation Plant in CIMS
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作者 马小平 许世范 《Journal of China University of Mining and Technology》 2001年第1期39-43,共5页
In this paper the method to calculate intangible quality cost is put forward for the first time based on the production and management characteristics of coal preparation plant. A model for assessment of quality manag... In this paper the method to calculate intangible quality cost is put forward for the first time based on the production and management characteristics of coal preparation plant. A model for assessment of quality management performance of coal preparation plant is established on the ground of quality cost. By using of CIMS integration environment the strategy to carry out the model and the application example are also offered. It provides a new and feasible way to assess performance quality management of coal preparation plant. 展开更多
关键词 CIMS 质量管理 质量成本 现代集成制造系统 选煤工艺
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