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Reliability-based life-cycle cost seismic design optimization of coastal bridge piers with nonuniform corrosion using different materials
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作者 Wu Xiangtong Yuan Wenting Guo Anxin 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期209-225,共17页
Reinforcement corrosion is the main cause of performance deterioration of reinforced concrete(RC)structures.Limited research has been performed to investigate the life-cycle cost(LCC)of coastal bridge piers with nonun... Reinforcement corrosion is the main cause of performance deterioration of reinforced concrete(RC)structures.Limited research has been performed to investigate the life-cycle cost(LCC)of coastal bridge piers with nonuniform corrosion using different materials.In this study,a reliability-based design optimization(RBDO)procedure is improved for the design of coastal bridge piers using six groups of commonly used materials,i.e.,normal performance concrete(NPC)with black steel(BS)rebar,high strength steel(HSS)rebar,epoxy coated(EC)rebar,and stainless steel(SS)rebar(named NPC-BS,NPC-HSS,NPC-EC,and NPC-SS,respectively),NPC with BS with silane soakage on the pier surface(named NPC-Silane),and high-performance concrete(HPC)with BS rebar(named HPC-BS).First,the RBDO procedure is improved for the design optimization of coastal bridge piers,and a bridge is selected to illustrate the procedure.Then,reliability analysis of the pier designed with each group of materials is carried out to obtain the time-dependent reliability in terms of the ultimate and serviceability performances.Next,the repair time of the pier is predicted based on the time-dependent reliability indices.Finally,the time-dependent LCCs for the pier are obtained for the selection of the optimal design. 展开更多
关键词 reliability-based design optimization(RBDO) life-cycle cost(LCC) nonuniform corrosion coastal bridge pier REPAIR
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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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Life-cycle cost analysis of optimal timing of pavement preservation 被引量:1
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作者 Zilong WANG Hao WANG 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2017年第1期17-26,共10页
Optimal application of pavement preservation or preventive maintenance is critical for highway agencies to allocate the limited budget for different treatments. This study developed an integrated life-cycle cost analy... Optimal application of pavement preservation or preventive maintenance is critical for highway agencies to allocate the limited budget for different treatments. This study developed an integrated life-cycle cost analysis (LCCA) model to quantify the impact of pavement preservation on agency cost and vehicle operation cost (VOC) and analyzed the optimal timing of preservation treatments. The international roughness index (IRI) data were extracted from the long-term pavement performance (LTPP) program specific pavement studies 3 (SPS-3) to determine the long-term effectiveness of preservation treatments on IRI deterioration. The traffic loading and the initial IRI value significantly affects life extension and the benefit of agency cost caused by pavement preservation. The benefit in VOC is one to two orders greater in magnitude as compared to the benefit in agency cost. The optimal timing calculated based on VOC is always earlier than the optimal timing calculated based on agency cost. There are considerable differences among the optimal timing of three preservation treatments. 展开更多
关键词 pavement preservation life-cycle cost analysis agency cost vehicle operation cost
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Design,simulation of different configurations and life-cycle cost analysis of solar photovoltaic-water-pumping system for agriculture applications:use cases and implementation issues
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作者 L.Ashok Kumar C.N.Lakshmiprasad +1 位作者 G.Ramaraj G.Sivasurya 《Clean Energy》 EI 2022年第2期335-352,共18页
Water is an essential resource for agriculture and the majority of land is irrigated through borewells or wells.The power requirement for an irrigation pump motor is fed by the on-grid power supply but the availabilit... Water is an essential resource for agriculture and the majority of land is irrigated through borewells or wells.The power requirement for an irrigation pump motor is fed by the on-grid power supply but the availability of electricity in rural areas is still questionable.With rising concerns about global warming and the rise in carbon footprints,it is necessary to choose clean and green energy,thereby attaining self-sustainable life.India receives yearly a mean solar irradiation of 6.5 kWh/m^(2)day.Hence,a solar photovoltaic-water-pumping system(SPV-WPS)is a suitable alternative to grid energy;thereby,the farmers would generate electricity through the solar photovoltaic system and become self-sufficient in their energy needs.In this paper,two different agricultural fields in Tamil Nadu,India that deploy flood irrigation and drip irrigation are taken as a case study.The paper discusses the concerns on the use of grid power and their carbon footprint,design and simulation of 4-and 5.5-kW SPV-WPSs using PVsyst 7.1.1,and the advantages of using SPV-WPSs and life-cycle cost analysis on different use cases.The Government of India has introduced a special scheme to promote the installation of SPV-WPSs by offering attractive incentives through PM-Kisan Urja Suraksha evam Utthaan Mahabhiyan(KUSUM)yojana.The results of the case study show that with the use of SPV-WPSs,either with or without subsidy,the farmer could gain a minimum of 250%on the investment with a project lifetime of 25 years. 展开更多
关键词 solar water pump PVsyst PM-KUSUM subsidy life-cycle cost sustainable development goal
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Advances in microfluidic-based DNA methylation analysis 被引量:1
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作者 Jiwen Li Tiechuan Li Xuexin Duan 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期116-134,共19页
DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various diseases.Progress in analytical methods can greatly increase the relevance of DNA methylation ... DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various diseases.Progress in analytical methods can greatly increase the relevance of DNA methylation studies to both clinical medicine and scientific research.Microflu-idic chips are excellent carriers for molecular analysis,and their use can provide improvements from multiple aspects.On-chip molecular analysis has received extensive attention owing to its advantages of portability,high throughput,low cost,and high efficiency.In recent years,the use of novel microfluidic chips for DNA methylation analysis has been widely reported and has shown obvious superiority to conventional methods.In this review,wefirst focus on DNA methylation and its applications.Then,we discuss advanced microfluidic-based methods for DNA methylation analysis and describe the great progress that has been made in recent years.Finally,we summarize the advantages that microfluidic technology brings to DNA methylation analysis and describe several challenges and perspectives for on-chip DNA methylation analysis.This review should help researchers improve their understanding and make progress in developing microfluidic-based methods for DNA methylation analysis. 展开更多
关键词 Microfluidic chip DNA methylation analysis Molecular analysis High throughput Low cost
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Capparis spinosa L waste activated carbon as an efficient adsorbent for crystal violet toxic dye removal: Modeling, optimization by experimental design, and ecological analysis
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作者 Mohammed Benjelloun Youssef Miyah +8 位作者 Salma Ssouni Soulaiman Iaich Mohamed El-habacha Salek Lagdali Khadija Saka El Mustafa Iboustaten Abdelaziz Ait Addi Sanae Lairini Rabia Bouslamti 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期283-302,共20页
Textile dyes are dramatic sources of pollution and non-aesthetic disturbance of aquatic life and therefore represent a potential risk of bioaccumulation that can affect living species.It is imperative to reduce or eli... Textile dyes are dramatic sources of pollution and non-aesthetic disturbance of aquatic life and therefore represent a potential risk of bioaccumulation that can affect living species.It is imperative to reduce or eliminate these dyes from liquid effluents with innovative biomaterials and methods.Therefore,this research aims to highlight the performance of Capparis spinosa L waste-activated carbon(CSLW-AC)adsorbent to remove crystal violet(CV)from an aqueous solution.The mechanism of CV adsorption on CSLW-AC was evaluated based on the coupling of experimental data and different characterization techniques.The efficiency of the CSLW-AC material reflected by the equilibrium adsorption capacity of CV could reach more than 195.671 mg·g^(–1) when 0.5 g·L^(–1) of CSLW-AC(Particle size≤250μm)is introduced into the CV of initial concentration of 100 mg·L^(–1) at pH 6 and temperature 65℃ and in the presence of potassium ions after 60 min of contact time according to the one parameter at a time studies.The adsorption behavior of CV on CSLW-AC was found to be consistent with the pseudo-second-order kinetic model and Frumkin's linear isothermal model.The thermodynamic aspects indicate that the process is physical,spontaneous,and endothermic.The optimization of the process by the Box Behnken design of experiments resulted in an adsorption capacity approaching 183.544 mg·g^(–1)([CV]=100 mg·L^(–1) and[CSLW-AC]=0.5 g·L^(–1) at 35 min).The results of the Lactuca sativa seeds germination in treated CV(70%),adsorbent solvent and thermal regeneration(more than 5 cycles),and process cost analysis(1.0484 USD·L^(–1))tests are encouraging and promising for future exploitations of the CSLW-AC material in different industrial fields. 展开更多
关键词 Box Behnken Capparis spinosa L waste-activated carbon cost analysis ISOTHERM KINETIC Regeneration
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Cost analysis of childhood glaucoma surgeries using the US Medicaire allowable costs 被引量:1
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作者 Abdelrahman M.Elhusseiny Mohamed M.Khodeiry +3 位作者 Nicolas A.Yannuzzi Ta C.Chang Richard K.Lee William E.Smiddy 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第5期700-704,共5页
AIM: To analyze and calculate the relative cost of various childhood glaucoma surgical interventions per mm Hg intraocular pressure(IOP) reduction($/mm Hg).METHODS: Representative index studies were reviewed to quanti... AIM: To analyze and calculate the relative cost of various childhood glaucoma surgical interventions per mm Hg intraocular pressure(IOP) reduction($/mm Hg).METHODS: Representative index studies were reviewed to quantitate the reduction of mean IOP and glaucoma medications for each surgical intervention in childhood glaucoma. A US perspective was adopted, using Medicare allowable costs to calculate cost/mm Hg IOP reduction($/mm Hg) at 1y postoperatively.RESULTS: At 1y postoperatively, the cost/mm Hg IOP reduction was $226/mm Hg for microcatheter-assisted circumferential trabeculotomy, $284/mm Hg for cyclophotocoagulation, $288/mm Hg for conventional ab-externo trabeculotomy, $338/mm Hg for Ahmed glaucoma valve, $350/mm Hg for Baerveldt glaucoma implant, $351/mm Hg for goniotomy, and $400/mm Hg for trabeculectomy.CONCLUSION: Microcatheter-assisted circumferential trabeculotomy is the most cost-efficient surgical method to lower IOP in childhood glaucoma, while trabeculectomy is the least cost-efficient surgical method. 展开更多
关键词 GLAUCOMA cost analysis TRABECULOTOMY TRABECULECTOMY intraocular pressure childhood glaucoma
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Direct cost variance analysis of peroral endoscopic myotomy vs heller myotomy for management of achalasia:A tertiary referral center experience
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作者 Syedreza Ali Haider Gregory S Bills +5 位作者 C Prakash Gyawali Passisd Laoveeravat Jordan Miller Samir Softic Mihir S Wagh Moamen Gabr 《World Journal of Gastrointestinal Endoscopy》 2023年第10期593-601,共9页
BACKGROUND Laparoscopic Heller myotomy(LHM)has been the traditional surgical treatment for achalasia.Recently,peroral endoscopic myotomy(POEM)has demonstrated similar clinical outcomes with shorter procedure times.Stu... BACKGROUND Laparoscopic Heller myotomy(LHM)has been the traditional surgical treatment for achalasia.Recently,peroral endoscopic myotomy(POEM)has demonstrated similar clinical outcomes with shorter procedure times.Studies comparing the direct cost-effectiveness of POEM vs LHM are limited.AIM To compare costs of POEM vs LHM.METHODS Haider SA et al.Comparing costs:POEM vs Heller myotomy WJGE https://www.wjgnet.com 594 October 16,2023 Volume 15 Issue 10 This retrospective chart review aimed to compare the outcomes and cost of clinical care between patients who underwent POEM and LHM procedures for achalasia.The study was conducted at a tertiary academic center from January 2019 to December 2020.Clinical outcomes,including post-operative Eckardt scores and adverse events,were assessed and compared between the two groups.Direct cost variance analysis was utilized to evaluate the cost of clinical care incurred by patients undergoing POEM in the year preceding the procedure,during the index admission,and one year post-procedure,in comparison to patients undergoing LHM.RESULTS Of 30 patients were included(15 POEM and 15 LHM)in the study.Patients in the POEM group had a mean Eckardt score of 0.5±0.5 post-procedure,which was no different from patients in the LHM group(0.7±0.6,P=0.17)indicating comparative efficacy.However,the total costs of the admission for the procedure in the LHM group were on average$1827 more expensive than in the POEM group(P<0.01).Total healthcare costs one year prior to index procedure were$7777 higher in the LHM group,but not statistically different(P=0.34).The patients in the LHM group one year after the index procedure had accrued$19730.24 larger total cost,although this was not statistically different from POEM group(P=0.68).CONCLUSION Despite similar clinical outcomes,the cost of the index procedure admission for POEM was significantly lower than for LHM.The difference was primarily related to shorter time increments utilized in the operating room during the index procedure,and shorter length of hospital stay following POEM. 展开更多
关键词 Peroral endoscopic myotomy cost analysis Laparoscopic Heller myotomy ACHALASIA
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The Environmental Impacts and Economic Benefits on Comprehensively Promoting Alternative Fuel Buses in China: Life-Cycle and Scenario Analysis Based on LEAP Model
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作者 Siting Xie 《Journal of Geoscience and Environment Protection》 2019年第4期99-121,共23页
With the continuous development of urban public transportation, the harmful GHG emissions and pollutants generated by itself and the consequent issues such as the losses of residents’ health, economic value and resid... With the continuous development of urban public transportation, the harmful GHG emissions and pollutants generated by itself and the consequent issues such as the losses of residents’ health, economic value and residents’ welfare have become the focus of social attention. In order to study the impacts of promoting new energy vehicles on public transportation pollution mitigation and residents’ health benefits, this paper adopts the LEAP model to build some scenarios that fulfill different development needs to quantitatively analyze the ownership of new energy buses, the reduction of pollutants and the losses of residents’ health welfare. It is concluded that promoting new energy buses comprehensively can significantly reduce the emissions of atmospheric pollutants and the economic losses of residents’ health, but cannot fully realize the targets of greenhouse gas reduction under Life Cycle Analysis. 展开更多
关键词 New Energy Buses Emission MITIGATION ECONOMIC BENEFITS life-cycle analysis SCENARIO 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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Cost-effectiveness analysis of treatments for metastatic castration resistant prostate cancer 被引量:6
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作者 Matthew E.Pollard Alan J.Moskowitz +1 位作者 Michael A.Diefenbach Simon J.Hall 《Asian Journal of Urology》 2017年第1期37-43,共7页
Objective:Treatment options for metastatic castration resistant prostate cancer(mCRPC)have expanded rapidly in recent years.Given the significant economic burden,we sought perform a cost-effectiveness analysis(CEA)of ... Objective:Treatment options for metastatic castration resistant prostate cancer(mCRPC)have expanded rapidly in recent years.Given the significant economic burden,we sought perform a cost-effectiveness analysis(CEA)of the contemporary treatment paradigm for mCRPC.Methods:We devised a treatment protocol consisting of sipuleucel-T,enzalutamide,abiraterone,docetaxel,radium-223,and cabazitaxel.We estimated number and length of treatments for each therapy using dosing schedules or progression free survival data from published clinical trials.We estimated treatment cost using billing data and Medicare reimbursement values and performed a CEA.Our analysis assumed US$100,000 per life year saved(LYS)as the threshold societal willingness to pay.Results:Incremental cost-effectiveness ratios(ICER)for strategies incorporating sipuleucel-T that were not eliminated by extended dominance exceeded the societal threshold willingnessto-pay of US$100,000 per LYS,the lowest of which was sipuleucel-T+enzalutamide+abiraterone+docetaxel at US$207,714 per LYS.Enzalutamide+abiraterone+docetaxel exhibited the most favorable ICER among strategies without sipuleucel-T at US$165,460 per LYS.Conclusion:Based on the available survival data and current costs of treatment,all treatment strategies greatly exceed a commonly assumed societal willingness-to-pay threshold of US$100,000 per LYS.Improvements in this regard can only comewith a reduction in pricing,better tailoring of treatment or significant enhancements in survival with clinical use of treatment combinations or sequences. 展开更多
关键词 Metastatic prostate cancer costs and cost analysis Health expenditures ECONOMICS PHARMACEUTICAL
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Competitive analysis of price online inventory problem with cost function 被引量:1
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作者 HAN Shu-guang GUO Jiu-ling +1 位作者 ZHANG Lu-ping HU Jue-liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第4期493-502,共10页
In this paper,a new price is given to the online decision maker at the beginning of each day.The trader must decide how many items to purchase according to the current price.We present three variants and an online alg... In this paper,a new price is given to the online decision maker at the beginning of each day.The trader must decide how many items to purchase according to the current price.We present three variants and an online algorithm based on cost function.The competitive ratio of the online algorithm is given for each variant,which is a performance measure of an online algorithm.More importantly,we show that the online algorithm is optimal. 展开更多
关键词 inventory problem price online cost function competitive analysis
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Cost analysis and outcomes of simple elbow dislocations 被引量:1
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作者 Michalis Panteli Ippokratis Pountos +2 位作者 Nikolaos K Kanakaris Theodoros H Tosounidis Peter V Giannoudis 《World Journal of Orthopedics》 2015年第7期513-520,共8页
AIM: To evaluate the management, clinical outcome and cost implications of three different treatment regimes for simple elbow dislocations.METHODS: Following institutional board approval, we performed a retrospective ... AIM: To evaluate the management, clinical outcome and cost implications of three different treatment regimes for simple elbow dislocations.METHODS: Following institutional board approval, we performed a retrospective review of all consecutive patients treated for simple elbow dislocations in a Level Ⅰ trauma centre between January 2008 and December 2010. Based on the length of elbow immobilisation(LOI), patients were divided in three groups(Group I, < 2 wk; Group Ⅱ, 2-3 wk; and Group Ⅲ, > 3 wk). Outcome was considered satisfactory when a patient could achieve a pain-free range of motion ≥ 100°(from 30° to 130°). The associated direct medical costs for the treatment of each patient were then calculated and analysed.RESULTS: We identified 80 patients who met the inclusion criteria. Due to loss to follow up, 13 patients were excluded from further analysis, leaving 67 patients for the final analysis. The mean LOI was 14 d(median 15 d; range 3-43 d) with a mean duration of hospital engagement of 67 d(median 57 d; range 10-351 d). Group Ⅲ(prolonged immobilisation) had a statistically significant worse outcome in comparison to Group Ⅰ?and Ⅱ(P = 0.04 and P = 0.01 respectively); however, there was no significant difference in the outcome between groups Ⅰ?and Ⅱ(P = 0.30). No statistically significantdifference in the direct medical costs between the groups was identified.CONCLUSION: The length of elbow immobilization doesn't influence the medical cost; however immobilisation longer than three weeks is associated with persistent stiffness and a less satisfactory clinical outcome. 展开更多
关键词 ELBOW dislocations SIMPLE MANAGEMENT OUTCOME cost analysis
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Comparison of School Building Construction Costs Estimation Methods Using Regression Analysis, Neural Network, and Support Vector Machine 被引量:2
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作者 Gwang-Hee Kim Jae-Min Shin +1 位作者 Sangyong Kim Yoonseok Shin 《Journal of Building Construction and Planning Research》 2013年第1期1-7,共7页
Accurate cost estimation at the early stage of a construction project is key factor in a project’s success. But it is difficult to quickly and accurately estimate construction costs at the planning stage, when drawin... Accurate cost estimation at the early stage of a construction project is key factor in a project’s success. But it is difficult to quickly and accurately estimate construction costs at the planning stage, when drawings, documentation and the like are still incomplete. As such, various techniques have been applied to accurately estimate construction costs at an early stage, when project information is limited. While the various techniques have their pros and cons, there has been little effort made to determine the best technique in terms of cost estimating performance. The objective of this research is to compare the accuracy of three estimating techniques (regression analysis (RA), neural network (NN), and support vector machine techniques (SVM)) by performing estimations of construction costs. By comparing the accuracy of these techniques using historical cost data, it was found that NN model showed more accurate estimation results than the RA and SVM models. Consequently, it is determined that NN model is most suitable for estimating the cost of school building projects. 展开更多
关键词 ESTIMATING Construction costS Regression analysis NEURAL Network Support VECTOR MACHINE
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Economic Viability of Smallholder Agroforestry and Beekeeping Projects in Uluguru Mountains, Tanzania: A Cost Benefit Analysis 被引量:2
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作者 Willickister R. Kadigi Yonika M. Ngaga Reuben M. J. Kadigi 《Open Journal of Forestry》 2021年第2期83-107,共25页
Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span... Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">Based Income Generating Activities (NIGAs) to improve livelihoods while at </span><span style="font-family:Verdana;">the same time enhancing biodiversity conservation in degrading</span><span style="font-family:Verdana;"> agro-ecologies. These activities can diversify and increase famers’ incomes and support in</span><span style="font-family:Verdana;">stinctive biota and fauna resilience. However, evidence to showcase and compare their long-term benefits is scant. We use the case of Uluguru</span><span style="font-family:Verdana;"> Mountains in Tanzania to evaluate and compare viability of agroforestry and beekeeping projects using the Cost</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Benefit Analysis (CBA) approach. The results of analysis yielded positive NPVs for both agroforestry and beekeeping projects at discount rates not higher than 8.2% and 8.5% respectively. Overall, the comparison of economic viability between agroforestry and beekeeping projects revealed that the former was relatively more profitable than the later in terms of both the NPV and Benefit</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Cost Ratio (BCR) criteria. However, the Internal Rate of Return (IRR) for beekeeping was slightly higher than that of agroforestry. Yet, we underscore the fact that these two projects can jointly be implemented to enhance livelihoods of farmers and support biodiversity conservation in the study </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">area </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">and other parts with similar agro-ecologies in developing countries. However, farmers in these agro-ecologies need to be supported by governments and non-government development partners in terms of training and inspiration to shift from orthodox farming to sustainable NIGAs. 展开更多
关键词 Uluguru Mountains Uluguru Forestry Reserve cost Benefit analysis Net Present Values Benefit cost Ratios Nature-Based Income Generating Activities
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Modeling Anthrax with Optimal Control and Cost Effectiveness Analysis 被引量:1
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作者 Shaibu Osman Dominic Otoo Oluwole Daniel Makinde 《Applied Mathematics》 2020年第3期255-275,共21页
Anthrax is an infection caused by bacteria and it affects both human and animal populations. The disease can be categorized under zoonotic diseases and humans can contract infections through contact with infected anim... Anthrax is an infection caused by bacteria and it affects both human and animal populations. The disease can be categorized under zoonotic diseases and humans can contract infections through contact with infected animals, ingest contaminated dairy and animal products. In this paper, we developed a mathematical model for anthrax transmission dynamics in both human and animal populations with optimal control. The qualitative solution of the model behaviour was analyzed by determining Rhv, equilibrium points and sensitivity analysis. A vaccination class was incorporated into the model with waning immunity. Local and global stability of the model’s equilibria was found to be locally asymptotically stable whenever Rhv Rhv. It was revealed that reducing animal and human interaction rate, would decrease Rhv. We extended the model to optimal control in order to find the best control strategy in reducing anthrax infections. It showed that the effective strategy in combating the anthrax epidemics is vaccination of animals and prevention of humans. 展开更多
关键词 ANTHRAX Model STABILITY analysis Sensitivity OPTIMAL Control cost EFFECTIVENESS
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Optimization of Evidence Analysis Cost Using Arbitrary Re-Sampling Techniques for Sample Influx into Forensic Science Laboratory 被引量:1
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作者 Samwel Victor Manyele 《Engineering(科研)》 2017年第5期457-481,共25页
This study analyzes the sample influx (samples per case file) into forensic science laboratory (FSL) and the corresponding analysis costs and uses arbitrary re-sampling plans to establish the minimum cost function. Th... This study analyzes the sample influx (samples per case file) into forensic science laboratory (FSL) and the corresponding analysis costs and uses arbitrary re-sampling plans to establish the minimum cost function. The demand for forensic analysis increased for all disciplines, especially biology/DNA between 2014 and 2015. While the average distribution of case files was about 42.5%, 40.6% and 17% for the three disciplines, the distribution of samples was rather different being 12%, 82.5% and 5.5% for samples requiring forensic biology, chemistry and toxicology analysis, respectively. Results show that most of the analysis workload was on forensic chemistry analysis. The cost of analysis for case files and the corresponding sample influx varied in the ratio of 35:6:1 and 28:12:1 for forensic chemistry, biology/DNA and toxicology for year 2014 for 2015, respectively. In the two consecutive years, the cost for forensic chemistry analysis was comparatively very high, necessitating re-sampling. The time series of sample influx in all disciplines are strongly stochastic, with higher magnitude for chemistry, biology/DNA and toxicology, in this order. The PDFs of sample influx data are highly skewed to the right, especially forensic toxicology and biology/DNA with peaks at 1 and 3 samples per case file. The arbitrary re-sampling plans were best suited to forensic chemistry case files (where re-sampling conditions apply). The locus of arbitrary number of samples to take from the submitted forensic samples was used to establish the minimum and scientifically acceptable samples by applying minimization function developed in this paper. The cost minimization function was also developed based on the average cost per sample and choice of re-sampling plans depending on the range of sample influx, from which the savings were determined and maximized. Thus, the study gives a forensic scientist a business model and scientific decision making tool on minimum number of samples to analyze focusing on savings on analysis cost. 展开更多
关键词 Forensic Science LABORATORY SAMPLE INFLUX ARBITRARY Sampling analysis cost Minimum Number of Samples Minimum analysis cost Toxicology Forensic Chemistry DNA analysis
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AIDS Treatments Efficiency Analysis Based on Cost Efficiency Data Envelopment Analysis Model 被引量:1
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作者 边馥萍 许茵 《Transactions of Tianjin University》 EI CAS 2007年第1期1-7,共7页
Three data envelopment analysis (DEA) models were used to analyse the relative efficiencies of four AIDS treatments in AIDS Clinical Trial Group (ACTG) Study 193A(1 309 patients in total, classified into 4 age groups)... Three data envelopment analysis (DEA) models were used to analyse the relative efficiencies of four AIDS treatments in AIDS Clinical Trial Group (ACTG) Study 193A(1 309 patients in total, classified into 4 age groups). Results from the output-oriented BCC model show that Treatment 4 ( 600 mg of zidovudine plus 400 mg of didanosine plus 400 mg of nevirapine) is particularly efficient for age group 14—25, but not efficient for the older age groups; Treatment 1 (600 mg of zidovudine alternating monthly with 400 mg of didanosine)and Treatment 2 (600 mg of zidovudine plus 2.25 mg of zalcitabine) are efficient for the age groups 35—45 and 45— ; age group 25—35 does not have a particularly efficient treatment, but Treatments 1 and 2 are relatively good. The cost efficiency BCC model, which takes the treatment cost into account, gives similar results as the output-oriented model. Results from the indirect output-oriented BCC model, which allows the replacement among medicines, show that the efficiency of Treatment 2 has greatly decreased compared with that of the output-oriented model, and a set of optimal medicine amounts for different age groups is obtained. 展开更多
关键词 data envelopment analysis (DEA) decision making unit DMU) cost efficient AIDS treatment
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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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Analysis on carbon emission reduction intensity of fuel cell vehicles from a life-cycle perspective
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作者 Ziyuan TENG Chao TAN +1 位作者 Peiyuan LIU Minfang HAN 《Frontiers in Energy》 SCIE EI CSCD 2024年第1期16-27,共12页
The hydrogen fuel cell vehicle is rapidly developing in China for carbon reduction and neutrality.This paper evaluated the life-cycle cost and carbon emission of hydrogen energy via lots of field surveys,including hyd... The hydrogen fuel cell vehicle is rapidly developing in China for carbon reduction and neutrality.This paper evaluated the life-cycle cost and carbon emission of hydrogen energy via lots of field surveys,including hydrogen production and packing in chlor-alkali plants,transport by tube trailers,storage and refueling in hydrogen refueling stations(HRSs),and application for use in two different cities.It also conducted a comparative study for battery electric vehicles(BEVs)and internal combustion engine vehicles(ICEVs).The result indicates that hydrogen fuel cell vehicle(FCV)has the best environmental performance but the highest energy cost.However,a sufficient hydrogen supply can significantly reduce the carbon intensity and FCV energy cost of the current system.The carbon emission for FCV application has the potential to decrease by 73.1%in City A and 43.8%in City B.It only takes 11.0%–20.1%of the BEV emission and 8.2%–9.8%of the ICEV emission.The cost of FCV driving can be reduced by 39.1%in City A.Further improvement can be obtained with an economical and“greener”hydrogen production pathway. 展开更多
关键词 hydrogen energy life-cycle assessment(LCA) fuel cell vehicle carbon emission energy cost
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