With the advent of the fourth industrial revolution,the construction industry has undergone a paradigm shift.The smart construction technology market is expected to grow 12%annually in developed countries due to advan...With the advent of the fourth industrial revolution,the construction industry has undergone a paradigm shift.The smart construction technology market is expected to grow 12%annually in developed countries due to advanced technology investments.It is expected that businesses requiring highly sophisticated technology,for instance companies that need their old facilities upgraded,will become the main focus of the market.As building information modeling(BIM)design is becoming mandatory,such as in the Korea Public Procurement Service,researches regarding building automation,construction,and operation integration management systems based on BIM are conducted.In addition,for construction projects of over 10 billion won,design value engineering(Design VE)implementation,including life cycle cost(LCC)analysis,is mandatory at the design stage to improve quality and reduce the lifetime costs of buildings.In this study,we propose an improvement plan for LCC analysis at the design stage using the KBIMS library,which is an open BIM library developed by the Korean government and research groups.We analyze the existing LCC method,KBIMS library,and attribute information,and model the process that is applied in the LCC analysis system.This is expected to complement the LCC analysis system and improve work productivity.展开更多
Pneumatic actuators and electric actuators have almost been applied to all manufacturing industries. The two kinds of actuators can replace each other in most fields, such as the point to point transmission occasion a...Pneumatic actuators and electric actuators have almost been applied to all manufacturing industries. The two kinds of actuators can replace each other in most fields, such as the point to point transmission occasion and some rotating occasions. However, there are very few research results about the advantages and disadvantages of two kinds of actuators under the same working conditions so far. In this paper, a novel comprehensive assessment method, named as overall life cycle comprehensive assessment (OLCCA), is proposed for comparison and assessment of pneumatic and electric actuators. OLCCA contains mechanical properties evaluation (MPE), life cycle cost analysis based on users (LCCABOU) and life cycle environmental impact analysis (LCEIA) algorithm in order to solve three difficult problems: mechanical properties assessment, cost analysis and environmental impact assessment about actuators. The mechanical properties evaluation of actuators is a multi-objective optimization problem. The fuzzy data quantification and information entropy methods are combined to establish MPE algorithm of actuators. Two kinds of pneumatic actuators and electric actuators with similar bearing capacity and similar work stroke were taken for example to verify the correctness of MPE algorithm. The case study of MPE algorithm for actuators verified its correctness. LCCABOU for actuators is also set up. Considering cost complex structure of pneumatic actuators, public device cost even method (PDCEM) is firstly presented to solve cost division of public devices such as compressors, aftercooler, receivers, etc. LCCABOU method is also effective and verified by the three groups of pneumatic actuators and electric actuators. Finally, LCEIA model of actuators is established for the environmental impact assessment of actuators. LCEIA data collection method and model establishment procedure for actuators are also put forward. With Simapro 7, LCEIA comparison results of six actuators can be obtained: Fossil fuels are the major environmental factor of pneumatic and electric actuators; Environmental impact of electric actuator is large than one of pneumatic actuator under the similar mechanical properties and working conditions of pneumatic and electric actuators. The results are correct and correspond with the actual mechanical properties of actuators. This paper proposes a comprehensive evaluation method of the actuators, which can solve the critical problem that similar electromechanical products are very difficult to be compared with each other from the angle of performance, cost and environment impact.展开更多
Reliability, maintainability, supportability (RMS) are the important performance indexes of equipment, which affect not only the availability, but also the life cycle cost (LCC) of the equipment. First discussed i...Reliability, maintainability, supportability (RMS) are the important performance indexes of equipment, which affect not only the availability, but also the life cycle cost (LCC) of the equipment. First discussed is the qualitative relation between reliability and LCC and the costs which may be used to enhance the reliability. Secondly, the factors that affect the maintainability are summarized, and if maintainability is advanced, the trend of the LCC is depicted. Thirdly, the qualitative relation between the supportability and LCC is described. Reliability, maintainability and supportability index all have a relation with the availability, so this paper presents the tradeoff for RMS indexes based on the availability calculation models and LCC models. On the condition that the availability value is not below the given value, the decision-making is optimal if the life cycle cost is the minimum value.展开更多
For facing the challenges brought by large-scale renewable energy having access to the system and considering the key technologies of energy Internet,it is very necessary to put forward the location method of distribu...For facing the challenges brought by large-scale renewable energy having access to the system and considering the key technologies of energy Internet,it is very necessary to put forward the location method of distribution network equipment and capacity from the perspective of life cycle cost.Compared with the traditional energy network,the equipment capacity problem of energy interconnected distribution network which involves in electricity network,thermal energy network and natural gas network is comprehensively considered in this paper.On this basis,firstly,the operation architecture of energy interconnected distribution network is designed.Secondly,taking the grid connection location and configuration capacity of key equipment in the system as the control variables and the operation cost of system comprehensive planning in the whole life cycle as the goal,the equipment location and capacity optimization model of energy interconnected distribution network is established.Finally,an IEEE 33 bus energy mutual distribution grid system is taken for example analysis,and the improved chaotic particle swarmoptimization algorithm is used to solve it.The simulation results show that the method proposed in this paper is suitable for the equipment location and capacity planning of energy interconnected distribution network,and it can effectively improve the social and economic benefits of system operation.展开更多
The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This stu...The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This study explains the concept and method of PV, and then provides an explanation of the concept and method of NPV, and points out the limitations in the practical application of the method.展开更多
The main driver for recycling cable wastes is the high value of the conducting metal, while the plastic with its lower value is often neglected. New improved cable plastic recycling routes can provide both economic an...The main driver for recycling cable wastes is the high value of the conducting metal, while the plastic with its lower value is often neglected. New improved cable plastic recycling routes can provide both economic and environmental incentive to cable producers for moving up the “cable plastic waste ladder”. Cradle-to-gate life cycle assessment, LCA, of the waste management of the cable scrap is suggested and explained as a method to analyze the pros and cons of different cable scrap recycling options at hand. Economic and environmental data about different recycling processes and other relevant processes and materials are given. Cable producers can use this data and method to assess the way they deal with the cable plastic waste today and compare it with available alternatives and thus illuminate the improvement potential of recycling cable plastic waste both in an environmental and in an economic sense. The methodology applied consists of: cradle-to-gate LCA for waste material to a recycled material (recyclate);quantifying the climate impact for each step on the waste ladder for the specific waste material;the use of economic and climate impact data in parallel;climate impact presented as a span to portray the insecurities related to which material the waste will replace;and possibilities for do-it-yourself calculations. Potentially, the methodology can be useful also for other waste materials in the future.展开更多
Life cycle cost technique is a powerful tool to make a scientific decision and a useful method of advancing the continuable development of the society. In this paper, development course, application actuality and up-t...Life cycle cost technique is a powerful tool to make a scientific decision and a useful method of advancing the continuable development of the society. In this paper, development course, application actuality and up-to-date research trends of life cycle cost technique in China are summarized. Some suggestions are given on how to general- ize the application of life cycle cost technique which are used as the reference to study life cycle cost technique.展开更多
This paper relates to a typical computer numerical control (CNC) machine, model FDXNC 128, and analyzes the payoff period quantitatively and forecasts the future maintenance cost and the evaluation of the economic be...This paper relates to a typical computer numerical control (CNC) machine, model FDXNC 128, and analyzes the payoff period quantitatively and forecasts the future maintenance cost and the evaluation of the economic benefit by using Life Cycle Cost (LCC) method and grey theory. The discussion shows conclusions that are beneficial to the production, management, and decision making of the enterprise.展开更多
Distribution generation(DG)technology based on a variety of renewable energy technologies has developed rapidly.A large number of multi-type DG are connected to the distribution network(DN),resulting in a decline in t...Distribution generation(DG)technology based on a variety of renewable energy technologies has developed rapidly.A large number of multi-type DG are connected to the distribution network(DN),resulting in a decline in the stability of DN operation.It is urgent to find a method that can effectively connect multi-energy DG to DN.photovoltaic(PV),wind power generation(WPG),fuel cell(FC),and micro gas turbine(MGT)are considered in this paper.A multi-objective optimization model was established based on the life cycle cost(LCC)of DG,voltage quality,voltage fluctuation,system network loss,power deviation of the tie-line,DG pollution emission index,and meteorological index weight of DN.Multi-objective artificial bee colony algorithm(MOABC)was used to determine the optimal location and capacity of the four kinds of DG access DN,and compared with the other three heuristic algorithms.Simulation tests based on IEEE 33 test node and IEEE 69 test node show that in IEEE 33 test node,the total voltage deviation,voltage fluctuation,and system network loss of DN decreased by 49.67%,7.47%and 48.12%,respectively,compared with that without DG configuration.In the IEEE 69 test node,the total voltage deviation,voltage fluctuation and system network loss of DN in the MOABC configuration scheme decreased by 54.98%,35.93%and 75.17%,respectively,compared with that without DG configuration,indicating that MOABC can reasonably plan the capacity and location of DG.Achieve the maximum trade-off between DG economy and DN operation stability.展开更多
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
Given the high demand for low-cost housing by the low-income earners,coupled with the tropical climate expe-rienced in sub-Saharan Africa,new-built housing stock needs utmost attention to cost,durability,and efficienc...Given the high demand for low-cost housing by the low-income earners,coupled with the tropical climate expe-rienced in sub-Saharan Africa,new-built housing stock needs utmost attention to cost,durability,and efficiency.With the walls accounting for a substantial proportion of the total building cost,choice of a wall system for use in building construction is critical.This choice usually depends on how durable,comfortable,ecological,and economical a given system is,to meet both the quality standards and low-cost aspects of housing.Although the earthbag building system allows for the construction of strong,affordable,and sustainable housing,it is not widely known.As such,its sustainable characteristics have gone unrecognised throughout the building industry.This paper examines and compares the thermal properties and total Life Cycle Costs(LCC)of earthbag walls with the commonly used burnt brick walls-based on the Degree-Days method and Life Cycle Costing analyses of building walls located in one of the hottest regions in Uganda.In-situ measurements of temperature and heat flux were conducted in accordance with ISO 9869 and the annual energy requirements obtained.The total LCC were calculated based on the initial construction costs and annual energy costs attributed to the building wall systems.Earthbags housing was found to be thermal-physically better than the brick wall with a lower U-value resulting in lower annual energy requirements and a huge saving in annual energy costs of up to 83.2%.This saving,coupled with low initial construction costs made the earthbag unit 68.7%cheaper than the burnt brick unit over a 30-year period.Therefore,this study findings suggest earthbag walling system as an economically viable and technically feasible low-cost construction option for rural areas and low-incomers earners’housing in warm climatic conditions,a characteristic of sub-Saharan countries-so as to promote regional development.展开更多
The paper focus on the life cycle analysis of stainless steels.It describes the system boundaries and gives an evaluation of the CO_2 emissions of Stainless Steels from cradle to gate.It gives as well an evaluation of...The paper focus on the life cycle analysis of stainless steels.It describes the system boundaries and gives an evaluation of the CO_2 emissions of Stainless Steels from cradle to gate.It gives as well an evaluation of the recycling rates of stainless steels according to the market applications and an evaluation of the overall cycle of manufacturing and scraps in 2005 on a world wide basis.It concludes with a presentation of some remarkable application focusing on green energy and future growth markets.展开更多
Previous test sequencing algorithms only consider the execution cost of a test at the application stage. Due to the fact that the placement cost of some tests at the design stage is considerably high compared with the...Previous test sequencing algorithms only consider the execution cost of a test at the application stage. Due to the fact that the placement cost of some tests at the design stage is considerably high compared with the execution cost, the sequential diagnosis strategy obtained by previous methods is actually not optimal from the view of life cycle. In this paper, the test sequencing problem based on life cycle cost is presented. It is formulated as an optimization problem, which is non-deterministic polynomial-time hard (NP-hard). An algorithm and a strategy to improve its computational efficiency are proposed. The formulation and algorithms are tested on various simulated systems and comparisons are made with the extant test sequencing methods. Application on a pump rotational speed control (PRSC) system of a spacecraft is studied in detail. Both the simulation results and the real-world case application results suggest that the solution proposed in this paper can significantly reduce the life cycle cost of a sequential fault diagnosis strategy.展开更多
A multi-layer adaptive optimizing parameters algorithm is developed forimproving least squares support vector machines (LS-SVM) , and a military aircraft life-cycle-cost(LCC) intelligent estimation model is proposed b...A multi-layer adaptive optimizing parameters algorithm is developed forimproving least squares support vector machines (LS-SVM) , and a military aircraft life-cycle-cost(LCC) intelligent estimation model is proposed based on the improved LS-SVM. The intelligent costestimation process is divided into three steps in the model. In the first step, a cost-drive-factorneeds to be selected, which is significant for cost estimation. In the second step, militaryaircraft training samples within costs and cost-drive-factor set are obtained by the LS-SVM. Thenthe model can be used for new type aircraft cost estimation. Chinese military aircraft costs areestimated in the paper. The results show that the estimated costs by the new model are closer to thetrue costs than that of the traditionally used methods.展开更多
<span style="font-family:Verdana;">This work presents the results of the characterization of a standalone photovoltaic system for the electrification of a household located in rural area in the western...<span style="font-family:Verdana;">This work presents the results of the characterization of a standalone photovoltaic system for the electrification of a household located in rural area in the western region of Cameroon: Nziih-Bafou in Dschang (5.35</span><span style="white-space:normal;background-color:#FFFFFF;font-family:Verdana;">°</span><span style="font-family:Verdana;">N, 10.05</span><span style="white-space:normal;background-color:#FFFFFF;font-family:Verdana;">°</span><span style="font-family:Verdana;">E and 1900 m). In order to cope with the</span><span "=""> </span><span style="font-family:Verdana;">maintenance charges and reduce the investment cost, a small mill was added to the appliances of the household for income generation. The assessment of the energy demand was made by taking into account the reactive energy due to the heavy</span><span "=""> </span><span style="font-family:Verdana;">consumption of energy by the mill’s motor, especially during ignition. The sizing of all the system’s components was carried out with the prospect of determining an optimum design in accordance with daily electricity demand, site irradiance profile and climatic conditions. In this context, tilt angles applicable to the PV structure and that allow</span><span "=""> </span><span style="font-family:Verdana;">to receive the maximum irradiance as a function of the periods of the year were determined using the Hay model.</span><span "=""> </span><span style="font-family:Verdana;">This approach provides the system with incident irradiance greater than or at the limit equal to that received by a horizontal surface on the same site</span><span "=""> </span><span style="font-family:Verdana;">compared to the case of a single tilt angle where the irradiance on the inclined plane is often lower than that</span><span "=""> </span><span "=""><span style="font-family:Verdana;">on the horizontal. The economic analysis of the PV system showed an </span><span style="font-family:Verdana;">initial cost of $4448</span></span><span "=""> </span><span style="font-family:Verdana;">and the Life Cost Cycle amounted to $24,495. This</span><span style="font-family:Verdana;"> amount corresponds to a present cost per kilowatt hour of $0.44. The Net Present Value</span><span "=""> </span><span style="font-family:Verdana;">(NPV) of the project ($7793) over its lifetime (20 years)</span><span "=""> </span><span style="font-family:Verdana;">shows a payback period of less than 4 years.</span>展开更多
With the growing economy of India, banking sector growth has led to installation of thousands of Automatic Teller Machines (ATMs) throughout the country. ATMs provide 24 × 7 services as well as operate at low-tem...With the growing economy of India, banking sector growth has led to installation of thousands of Automatic Teller Machines (ATMs) throughout the country. ATMs provide 24 × 7 services as well as operate at low-temperature ranges of cooling, hence have high operating energy costs. Insulating an ATM’s envelope is not a prevalent technique in India. In the present study, an effort has been made to determine the optimum insulation thickness for three different insulation materials for the typical ATM envelope in four different climatic zones of India. Life cycle savings and payback periods for various insulation materials are also evaluated. Further, these optimally insulated ATM envelopes can be integrated with grid connected rooftop solar PV systems. The energy saving and emissions reduction potential due to these two interventions have been estimated on the national basis. Altogether in the four selected climate zones, energy saving of 17% - 30% provides the annual economic benefit of Indian National Rupees (Rs.) 3570 million with annual carbon reduction potential of about 0.60 million tCO<sub>2</sub>. From this study, it is observed that properly insulated ATMs integrated with rooftop solar PV systems, can significantly reduce the energy costs as well as carbon emissions in India’s context.展开更多
A new concept is proposed that susceptibility, vulnerability, reliability, maintainability and supportability should be essential factors of aircraft combat survivability. A weight coefficient method and a synthetic m...A new concept is proposed that susceptibility, vulnerability, reliability, maintainability and supportability should be essential factors of aircraft combat survivability. A weight coefficient method and a synthetic method are proposed to estimate aircraft combat survivability based on the essential factors. Considering that it takes cost to enhance aircraft combat survivability, a synthetic tradeoff model between aircraft combat survivability and life cycle cost is built. The aircraft combat survivability estimation methods and synthetic tradeoff with a life cycle cost model will be helpful for aircraft combat survivability design and enhancement.展开更多
By comparing the advantages and disadvantages of the main popular maintenance modes, this paper analyses the relationship between maintenance modes, and gives a model of maintenance decision-making. The model can be u...By comparing the advantages and disadvantages of the main popular maintenance modes, this paper analyses the relationship between maintenance modes, and gives a model of maintenance decision-making. The model can be used in enterprises to minimize life cycle cost (LCC).展开更多
The upscaling requirements of energy transition highlight the urgent need for ramping up renewables and boosting system efficiencies.However,the stochastic nature of excessive renewable energy resources has challenged...The upscaling requirements of energy transition highlight the urgent need for ramping up renewables and boosting system efficiencies.However,the stochastic nature of excessive renewable energy resources has challenged stable and efficient operation of the power system.Battery energy storage systems(BESSs)have been identified as critical to mitigate random fluctuations,unnecessary green energy curtailment and load shedding with rapid response and flexible connection.On the other hand,an AC/DC hybrid distribution system can offer merged benefits in both AC and DC subsystems without additional losses during AC/DC power conversion.Therefore,configuring BESSs on an AC/DC distribution system is wellpositioned to meet challenges brought by carbon reductions in an efficient way.A bi-level optimization model of BESS capacity allocation for AC/DC hybrid distribution systems,considering the flexibility of voltage source converters(VSCs)and power conversion systems(PCSs),has been established in this paper to address the techno-economic issues that hindered wide implementation.The large-scale nonlinear programming problem has been solved utilizing a genetic algorithm combined with second-order cone programming.Rationality and effectiveness of the model have been verified by setting different scenarios through case studies.Simulation results have demonstrated the coordinated operation of BESS and AC/DC hybrid systems can effectively suppress voltage fluctuations and improve the cost-benefit of BESSs from a life cycle angle.展开更多
This paper aims to discuss an environmental, social, and economic analysis of energy utilization of crop residues from life cycle perspectives in China. The methodologies employed to achieve this objective are environ...This paper aims to discuss an environmental, social, and economic analysis of energy utilization of crop residues from life cycle perspectives in China. The methodologies employed to achieve this objective are environmental life cycle assessment (E-LCA), life cycle cost (LCC), and social life cycle assessment (S-LCA). Five scenarios are developed based on the conversion technologies and final bioenergy products. The system boundaries include crop residue collection, transportation, pre-treatment, and conversion process. The replaced amounts of energy are also taken into account in the E-LCA analysis. The functional unit is defined as 1 MJ of energy produced. Eight impact categories are considered besides climate change in E-LCA. The investment capital cost and salary cost are collected and compared in the life cycle of the scenarios. Three stakeholders and several subcategories are considered in the S-LCA analysis defined by UNEP/SETAS guidelines. The results show that the energy utilization of crop residue has carbon emission factors of 0.09–0.18 kg (CO2 eq per 1 MJ), and presents a net carbon emissions reduction of 0.03–0.15 kg (CO2 eq per 1 MJ) compared with the convectional electricity or petrol, but the other impacts should be paid attention to in the biomass energy scenarios. The energy utilization of crop residues can bring economic benefit to local communities and the society, but the working conditions of local workers need to be improved in future biomass energy development.展开更多
文摘With the advent of the fourth industrial revolution,the construction industry has undergone a paradigm shift.The smart construction technology market is expected to grow 12%annually in developed countries due to advanced technology investments.It is expected that businesses requiring highly sophisticated technology,for instance companies that need their old facilities upgraded,will become the main focus of the market.As building information modeling(BIM)design is becoming mandatory,such as in the Korea Public Procurement Service,researches regarding building automation,construction,and operation integration management systems based on BIM are conducted.In addition,for construction projects of over 10 billion won,design value engineering(Design VE)implementation,including life cycle cost(LCC)analysis,is mandatory at the design stage to improve quality and reduce the lifetime costs of buildings.In this study,we propose an improvement plan for LCC analysis at the design stage using the KBIMS library,which is an open BIM library developed by the Korean government and research groups.We analyze the existing LCC method,KBIMS library,and attribute information,and model the process that is applied in the LCC analysis system.This is expected to complement the LCC analysis system and improve work productivity.
基金Supported by Doctoral Foundation of Henan Polytechnic University(Grant No.B2012-101)Opening Project of Key Laboratory of Precision Manufacturing Technology and Engineering of Henan Polytechnic University,China(Grant No.PMTE201318A)Henan Provincial Science and Technology Research Projects of Education Department of China(Grant No.14B460033)
文摘Pneumatic actuators and electric actuators have almost been applied to all manufacturing industries. The two kinds of actuators can replace each other in most fields, such as the point to point transmission occasion and some rotating occasions. However, there are very few research results about the advantages and disadvantages of two kinds of actuators under the same working conditions so far. In this paper, a novel comprehensive assessment method, named as overall life cycle comprehensive assessment (OLCCA), is proposed for comparison and assessment of pneumatic and electric actuators. OLCCA contains mechanical properties evaluation (MPE), life cycle cost analysis based on users (LCCABOU) and life cycle environmental impact analysis (LCEIA) algorithm in order to solve three difficult problems: mechanical properties assessment, cost analysis and environmental impact assessment about actuators. The mechanical properties evaluation of actuators is a multi-objective optimization problem. The fuzzy data quantification and information entropy methods are combined to establish MPE algorithm of actuators. Two kinds of pneumatic actuators and electric actuators with similar bearing capacity and similar work stroke were taken for example to verify the correctness of MPE algorithm. The case study of MPE algorithm for actuators verified its correctness. LCCABOU for actuators is also set up. Considering cost complex structure of pneumatic actuators, public device cost even method (PDCEM) is firstly presented to solve cost division of public devices such as compressors, aftercooler, receivers, etc. LCCABOU method is also effective and verified by the three groups of pneumatic actuators and electric actuators. Finally, LCEIA model of actuators is established for the environmental impact assessment of actuators. LCEIA data collection method and model establishment procedure for actuators are also put forward. With Simapro 7, LCEIA comparison results of six actuators can be obtained: Fossil fuels are the major environmental factor of pneumatic and electric actuators; Environmental impact of electric actuator is large than one of pneumatic actuator under the similar mechanical properties and working conditions of pneumatic and electric actuators. The results are correct and correspond with the actual mechanical properties of actuators. This paper proposes a comprehensive evaluation method of the actuators, which can solve the critical problem that similar electromechanical products are very difficult to be compared with each other from the angle of performance, cost and environment impact.
基金supported by the National Postdoctoral Science Foundation of P. R. China Under Grant No. 20080431380
文摘Reliability, maintainability, supportability (RMS) are the important performance indexes of equipment, which affect not only the availability, but also the life cycle cost (LCC) of the equipment. First discussed is the qualitative relation between reliability and LCC and the costs which may be used to enhance the reliability. Secondly, the factors that affect the maintainability are summarized, and if maintainability is advanced, the trend of the LCC is depicted. Thirdly, the qualitative relation between the supportability and LCC is described. Reliability, maintainability and supportability index all have a relation with the availability, so this paper presents the tradeoff for RMS indexes based on the availability calculation models and LCC models. On the condition that the availability value is not below the given value, the decision-making is optimal if the life cycle cost is the minimum value.
基金The authors received specific funding for State Grid Corporation Headquarters Project Support,Key Technologies and Applications of Planning and Decision-Making Based on the Full Cost Chain of the Power Grid,Grant No.5205331800001.
文摘For facing the challenges brought by large-scale renewable energy having access to the system and considering the key technologies of energy Internet,it is very necessary to put forward the location method of distribution network equipment and capacity from the perspective of life cycle cost.Compared with the traditional energy network,the equipment capacity problem of energy interconnected distribution network which involves in electricity network,thermal energy network and natural gas network is comprehensively considered in this paper.On this basis,firstly,the operation architecture of energy interconnected distribution network is designed.Secondly,taking the grid connection location and configuration capacity of key equipment in the system as the control variables and the operation cost of system comprehensive planning in the whole life cycle as the goal,the equipment location and capacity optimization model of energy interconnected distribution network is established.Finally,an IEEE 33 bus energy mutual distribution grid system is taken for example analysis,and the improved chaotic particle swarmoptimization algorithm is used to solve it.The simulation results show that the method proposed in this paper is suitable for the equipment location and capacity planning of energy interconnected distribution network,and it can effectively improve the social and economic benefits of system operation.
文摘The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This study explains the concept and method of PV, and then provides an explanation of the concept and method of NPV, and points out the limitations in the practical application of the method.
文摘The main driver for recycling cable wastes is the high value of the conducting metal, while the plastic with its lower value is often neglected. New improved cable plastic recycling routes can provide both economic and environmental incentive to cable producers for moving up the “cable plastic waste ladder”. Cradle-to-gate life cycle assessment, LCA, of the waste management of the cable scrap is suggested and explained as a method to analyze the pros and cons of different cable scrap recycling options at hand. Economic and environmental data about different recycling processes and other relevant processes and materials are given. Cable producers can use this data and method to assess the way they deal with the cable plastic waste today and compare it with available alternatives and thus illuminate the improvement potential of recycling cable plastic waste both in an environmental and in an economic sense. The methodology applied consists of: cradle-to-gate LCA for waste material to a recycled material (recyclate);quantifying the climate impact for each step on the waste ladder for the specific waste material;the use of economic and climate impact data in parallel;climate impact presented as a span to portray the insecurities related to which material the waste will replace;and possibilities for do-it-yourself calculations. Potentially, the methodology can be useful also for other waste materials in the future.
基金supported by the National Postdoctoral Science Foundation of P.R.China under Grant No.20080431380
文摘Life cycle cost technique is a powerful tool to make a scientific decision and a useful method of advancing the continuable development of the society. In this paper, development course, application actuality and up-to-date research trends of life cycle cost technique in China are summarized. Some suggestions are given on how to general- ize the application of life cycle cost technique which are used as the reference to study life cycle cost technique.
文摘This paper relates to a typical computer numerical control (CNC) machine, model FDXNC 128, and analyzes the payoff period quantitatively and forecasts the future maintenance cost and the evaluation of the economic benefit by using Life Cycle Cost (LCC) method and grey theory. The discussion shows conclusions that are beneficial to the production, management, and decision making of the enterprise.
文摘Distribution generation(DG)technology based on a variety of renewable energy technologies has developed rapidly.A large number of multi-type DG are connected to the distribution network(DN),resulting in a decline in the stability of DN operation.It is urgent to find a method that can effectively connect multi-energy DG to DN.photovoltaic(PV),wind power generation(WPG),fuel cell(FC),and micro gas turbine(MGT)are considered in this paper.A multi-objective optimization model was established based on the life cycle cost(LCC)of DG,voltage quality,voltage fluctuation,system network loss,power deviation of the tie-line,DG pollution emission index,and meteorological index weight of DN.Multi-objective artificial bee colony algorithm(MOABC)was used to determine the optimal location and capacity of the four kinds of DG access DN,and compared with the other three heuristic algorithms.Simulation tests based on IEEE 33 test node and IEEE 69 test node show that in IEEE 33 test node,the total voltage deviation,voltage fluctuation,and system network loss of DN decreased by 49.67%,7.47%and 48.12%,respectively,compared with that without DG configuration.In the IEEE 69 test node,the total voltage deviation,voltage fluctuation and system network loss of DN in the MOABC configuration scheme decreased by 54.98%,35.93%and 75.17%,respectively,compared with that without DG configuration,indicating that MOABC can reasonably plan the capacity and location of DG.Achieve the maximum trade-off between DG economy and DN operation stability.
文摘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.
文摘Given the high demand for low-cost housing by the low-income earners,coupled with the tropical climate expe-rienced in sub-Saharan Africa,new-built housing stock needs utmost attention to cost,durability,and efficiency.With the walls accounting for a substantial proportion of the total building cost,choice of a wall system for use in building construction is critical.This choice usually depends on how durable,comfortable,ecological,and economical a given system is,to meet both the quality standards and low-cost aspects of housing.Although the earthbag building system allows for the construction of strong,affordable,and sustainable housing,it is not widely known.As such,its sustainable characteristics have gone unrecognised throughout the building industry.This paper examines and compares the thermal properties and total Life Cycle Costs(LCC)of earthbag walls with the commonly used burnt brick walls-based on the Degree-Days method and Life Cycle Costing analyses of building walls located in one of the hottest regions in Uganda.In-situ measurements of temperature and heat flux were conducted in accordance with ISO 9869 and the annual energy requirements obtained.The total LCC were calculated based on the initial construction costs and annual energy costs attributed to the building wall systems.Earthbags housing was found to be thermal-physically better than the brick wall with a lower U-value resulting in lower annual energy requirements and a huge saving in annual energy costs of up to 83.2%.This saving,coupled with low initial construction costs made the earthbag unit 68.7%cheaper than the burnt brick unit over a 30-year period.Therefore,this study findings suggest earthbag walling system as an economically viable and technically feasible low-cost construction option for rural areas and low-incomers earners’housing in warm climatic conditions,a characteristic of sub-Saharan countries-so as to promote regional development.
文摘The paper focus on the life cycle analysis of stainless steels.It describes the system boundaries and gives an evaluation of the CO_2 emissions of Stainless Steels from cradle to gate.It gives as well an evaluation of the recycling rates of stainless steels according to the market applications and an evaluation of the overall cycle of manufacturing and scraps in 2005 on a world wide basis.It concludes with a presentation of some remarkable application focusing on green energy and future growth markets.
基金supported by China Civil Space Foundation(No.C1320063131)
文摘Previous test sequencing algorithms only consider the execution cost of a test at the application stage. Due to the fact that the placement cost of some tests at the design stage is considerably high compared with the execution cost, the sequential diagnosis strategy obtained by previous methods is actually not optimal from the view of life cycle. In this paper, the test sequencing problem based on life cycle cost is presented. It is formulated as an optimization problem, which is non-deterministic polynomial-time hard (NP-hard). An algorithm and a strategy to improve its computational efficiency are proposed. The formulation and algorithms are tested on various simulated systems and comparisons are made with the extant test sequencing methods. Application on a pump rotational speed control (PRSC) system of a spacecraft is studied in detail. Both the simulation results and the real-world case application results suggest that the solution proposed in this paper can significantly reduce the life cycle cost of a sequential fault diagnosis strategy.
文摘A multi-layer adaptive optimizing parameters algorithm is developed forimproving least squares support vector machines (LS-SVM) , and a military aircraft life-cycle-cost(LCC) intelligent estimation model is proposed based on the improved LS-SVM. The intelligent costestimation process is divided into three steps in the model. In the first step, a cost-drive-factorneeds to be selected, which is significant for cost estimation. In the second step, militaryaircraft training samples within costs and cost-drive-factor set are obtained by the LS-SVM. Thenthe model can be used for new type aircraft cost estimation. Chinese military aircraft costs areestimated in the paper. The results show that the estimated costs by the new model are closer to thetrue costs than that of the traditionally used methods.
文摘<span style="font-family:Verdana;">This work presents the results of the characterization of a standalone photovoltaic system for the electrification of a household located in rural area in the western region of Cameroon: Nziih-Bafou in Dschang (5.35</span><span style="white-space:normal;background-color:#FFFFFF;font-family:Verdana;">°</span><span style="font-family:Verdana;">N, 10.05</span><span style="white-space:normal;background-color:#FFFFFF;font-family:Verdana;">°</span><span style="font-family:Verdana;">E and 1900 m). In order to cope with the</span><span "=""> </span><span style="font-family:Verdana;">maintenance charges and reduce the investment cost, a small mill was added to the appliances of the household for income generation. The assessment of the energy demand was made by taking into account the reactive energy due to the heavy</span><span "=""> </span><span style="font-family:Verdana;">consumption of energy by the mill’s motor, especially during ignition. The sizing of all the system’s components was carried out with the prospect of determining an optimum design in accordance with daily electricity demand, site irradiance profile and climatic conditions. In this context, tilt angles applicable to the PV structure and that allow</span><span "=""> </span><span style="font-family:Verdana;">to receive the maximum irradiance as a function of the periods of the year were determined using the Hay model.</span><span "=""> </span><span style="font-family:Verdana;">This approach provides the system with incident irradiance greater than or at the limit equal to that received by a horizontal surface on the same site</span><span "=""> </span><span style="font-family:Verdana;">compared to the case of a single tilt angle where the irradiance on the inclined plane is often lower than that</span><span "=""> </span><span "=""><span style="font-family:Verdana;">on the horizontal. The economic analysis of the PV system showed an </span><span style="font-family:Verdana;">initial cost of $4448</span></span><span "=""> </span><span style="font-family:Verdana;">and the Life Cost Cycle amounted to $24,495. This</span><span style="font-family:Verdana;"> amount corresponds to a present cost per kilowatt hour of $0.44. The Net Present Value</span><span "=""> </span><span style="font-family:Verdana;">(NPV) of the project ($7793) over its lifetime (20 years)</span><span "=""> </span><span style="font-family:Verdana;">shows a payback period of less than 4 years.</span>
文摘With the growing economy of India, banking sector growth has led to installation of thousands of Automatic Teller Machines (ATMs) throughout the country. ATMs provide 24 × 7 services as well as operate at low-temperature ranges of cooling, hence have high operating energy costs. Insulating an ATM’s envelope is not a prevalent technique in India. In the present study, an effort has been made to determine the optimum insulation thickness for three different insulation materials for the typical ATM envelope in four different climatic zones of India. Life cycle savings and payback periods for various insulation materials are also evaluated. Further, these optimally insulated ATM envelopes can be integrated with grid connected rooftop solar PV systems. The energy saving and emissions reduction potential due to these two interventions have been estimated on the national basis. Altogether in the four selected climate zones, energy saving of 17% - 30% provides the annual economic benefit of Indian National Rupees (Rs.) 3570 million with annual carbon reduction potential of about 0.60 million tCO<sub>2</sub>. From this study, it is observed that properly insulated ATMs integrated with rooftop solar PV systems, can significantly reduce the energy costs as well as carbon emissions in India’s context.
文摘A new concept is proposed that susceptibility, vulnerability, reliability, maintainability and supportability should be essential factors of aircraft combat survivability. A weight coefficient method and a synthetic method are proposed to estimate aircraft combat survivability based on the essential factors. Considering that it takes cost to enhance aircraft combat survivability, a synthetic tradeoff model between aircraft combat survivability and life cycle cost is built. The aircraft combat survivability estimation methods and synthetic tradeoff with a life cycle cost model will be helpful for aircraft combat survivability design and enhancement.
文摘By comparing the advantages and disadvantages of the main popular maintenance modes, this paper analyses the relationship between maintenance modes, and gives a model of maintenance decision-making. The model can be used in enterprises to minimize life cycle cost (LCC).
基金supported in part by the National Natural Science Foundation of China(No.51777134)in part by a joint project of NSFC of China and EPSRC of UK(No.52061635103 and EP/T021969/1).
文摘The upscaling requirements of energy transition highlight the urgent need for ramping up renewables and boosting system efficiencies.However,the stochastic nature of excessive renewable energy resources has challenged stable and efficient operation of the power system.Battery energy storage systems(BESSs)have been identified as critical to mitigate random fluctuations,unnecessary green energy curtailment and load shedding with rapid response and flexible connection.On the other hand,an AC/DC hybrid distribution system can offer merged benefits in both AC and DC subsystems without additional losses during AC/DC power conversion.Therefore,configuring BESSs on an AC/DC distribution system is wellpositioned to meet challenges brought by carbon reductions in an efficient way.A bi-level optimization model of BESS capacity allocation for AC/DC hybrid distribution systems,considering the flexibility of voltage source converters(VSCs)and power conversion systems(PCSs),has been established in this paper to address the techno-economic issues that hindered wide implementation.The large-scale nonlinear programming problem has been solved utilizing a genetic algorithm combined with second-order cone programming.Rationality and effectiveness of the model have been verified by setting different scenarios through case studies.Simulation results have demonstrated the coordinated operation of BESS and AC/DC hybrid systems can effectively suppress voltage fluctuations and improve the cost-benefit of BESSs from a life cycle angle.
文摘This paper aims to discuss an environmental, social, and economic analysis of energy utilization of crop residues from life cycle perspectives in China. The methodologies employed to achieve this objective are environmental life cycle assessment (E-LCA), life cycle cost (LCC), and social life cycle assessment (S-LCA). Five scenarios are developed based on the conversion technologies and final bioenergy products. The system boundaries include crop residue collection, transportation, pre-treatment, and conversion process. The replaced amounts of energy are also taken into account in the E-LCA analysis. The functional unit is defined as 1 MJ of energy produced. Eight impact categories are considered besides climate change in E-LCA. The investment capital cost and salary cost are collected and compared in the life cycle of the scenarios. Three stakeholders and several subcategories are considered in the S-LCA analysis defined by UNEP/SETAS guidelines. The results show that the energy utilization of crop residue has carbon emission factors of 0.09–0.18 kg (CO2 eq per 1 MJ), and presents a net carbon emissions reduction of 0.03–0.15 kg (CO2 eq per 1 MJ) compared with the convectional electricity or petrol, but the other impacts should be paid attention to in the biomass energy scenarios. The energy utilization of crop residues can bring economic benefit to local communities and the society, but the working conditions of local workers need to be improved in future biomass energy development.