期刊文献+
共找到10,243篇文章
< 1 2 250 >
每页显示 20 50 100
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
1
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
下载PDF
Advances in microfluidic-based DNA methylation analysis 被引量:1
2
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
下载PDF
Capparis spinosa L waste activated carbon as an efficient adsorbent for crystal violet toxic dye removal: Modeling, optimization by experimental design, and ecological analysis
3
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
下载PDF
Cost analysis of childhood glaucoma surgeries using the US Medicaire allowable costs 被引量:1
4
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
下载PDF
Direct cost variance analysis of peroral endoscopic myotomy vs heller myotomy for management of achalasia:A tertiary referral center experience
5
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
下载PDF
Cost-benefit analysis of screening for diabetic retinopathy among Chinese type 2 diabetes: decision from different perspectives of a population-based study 被引量:2
6
作者 Ching-Ching Peng Pesus Chou +6 位作者 Tao-Hsin Tung Wu-Hsiung Chien Fenq-Lih Lee Shih-Jen Chen Shih-Tzer Tsai Chi-Ming Liu Jorn-Hon Liu 《Health》 2009年第4期304-312,共9页
The purpose of this study is to explore whether it is worthwhile to launch a routine diabetic retinopathy (DR) screening for blindness pre-vention among Chinese type 2 diabetes from different perspective based on the ... The purpose of this study is to explore whether it is worthwhile to launch a routine diabetic retinopathy (DR) screening for blindness pre-vention among Chinese type 2 diabetes from different perspective based on the popula-tion-based study in Kinmen, Taiwan. A total of 971 community dwelling adults previously di-agnosed with type 2 diabetes in 1991-1993 un-derwent DR screening in 1999-2002 by a panel of ophthalmologists using on-site indirect oph-thalmoscopy and 45-degree color fundus retinal photographs. The cost-benefit analysis is used to evaluate the DR screening. In terms of bene-fit-cost ratio, the different screening programs for DR could save New Taiwan Dollars (NTD) from 14.38 to 36.83 in discounted costs for each dollar incurred in different screening years from the societal viewpoint for Taiwan and save NTD from 0.81 to 1.80 in different screening years from health care payer’s perspective. The av-erage estimate of willingness-to-pay to translate into benefit yields NTD from 937.8 to 4,689 be- nefits per case due to DR screening in different screening years during 10-year follow-up. The net present value of the DR screening were NTD from -167,318 to -307,251.2 in different screening years. In conclusion, it is worthwhile to initial a routine DR screening of Chinese type 2 diabetes for blindness prevention from the societal per-spective but not from consumer decision based on the willingness-to-pay perspective. 展开更多
关键词 Type 2 DIABETES DIABETIC RETINOPATHY cost-benefit analysis POPULATION-BASED Study
下载PDF
A New Criteria to Apply Weight-Dependent CATSthr to Cost-Benefit Analysis within the Framework of IMO EnvironmentaI-FSA Studies
7
作者 Y. Yamada F. Kaneko 《Journal of Shipping and Ocean Engineering》 2011年第1期65-76,共12页
The purpose of this paper is to investigate reasonable cost benefit criteria within the framework of environmental formal safety assessment (FSA). In this study a statistical analysis of oil spill data was carried o... The purpose of this paper is to investigate reasonable cost benefit criteria within the framework of environmental formal safety assessment (FSA). In this study a statistical analysis of oil spill data was carried out based on the report of International Oil Pollution Compensation Funds. According to the statistical study of actual oil spill from tankers, it is found that collisions and groundings are the most probable causes of the oil spills from tankers. Probability distributions of costs of oil spill and oil spill amount are investigated, and a non-linear regression formula between costs of oil spills and oil spill weight are derived. Using the regression formula, an oil spill weight dependent CATStm (Cost of Averting a Ton of oil Spilt) is proposed. Moreover in order to apply the weight dependent CATSthr to cost benefit analysis (CBA), a new cost-effective criterion is newly proposed with considering its concrete application to environmental FSA. 展开更多
关键词 cost of oil spill formal safety assessment cost benefit analysis CAF CATS.
下载PDF
Cost-benefit Analysis of Chestnut Production in Xingtai County
8
作者 Yuji JIN 《Asian Agricultural Research》 2014年第4期33-37,共5页
On the basis of market demand survey of chestnut,this article carries out cost-benefit analysis of the chestnut production in Xingtai County,to understand the profitability and payback period of local chestnut product... On the basis of market demand survey of chestnut,this article carries out cost-benefit analysis of the chestnut production in Xingtai County,to understand the profitability and payback period of local chestnut production.It points out that chestnut production has a high rate of return on investment,and chestnut can be promoted on a large scale in Xingtai County.However,there are still some problems in the production and marketing of chestnut in Xingtai County,such as low level of technology,extensive management,low level of organization,market imperfections and weak brand consciousness.Based on these problems,corresponding recommendations are put forth. 展开更多
关键词 CHESTNUT cost-benefit analysis XINGTAI COUNTY
下载PDF
Study on Cost of Environmental Degradation Based on Cost-Benefit Analysis
9
作者 Xu FANG Jiaming ZHU Penghui YANG 《Asian Agricultural Research》 2019年第6期1-4,共4页
With the rapid economic development of China,the environmental degradation brought by economic development cannot be ignored.In order to measure the cost of environmental degradation brought by land projects in the pr... With the rapid economic development of China,the environmental degradation brought by economic development cannot be ignored.In order to measure the cost of environmental degradation brought by land projects in the process of economic development and evaluate a land project,this paper establishes an ecological service evaluation model based on cost-benefit method to analyze the cost and benefit of land development projects from a new perspective,and explore effective strategies to alleviate environmental degradation. 展开更多
关键词 ENVIRONMENTAL DEGRADATION LAND development cost-benefit analysis ECOLOGICAL service assessment
下载PDF
Evaluating and Improving the Effectiveness of Vehicle Inspection and Maintenance Programs: A Cost-Benefit Analysis Framework
10
作者 Ying Li 《Journal of Environmental Protection》 2017年第12期1541-1566,共26页
Motor vehicle inspection and maintenance (I/M) programs are designed to identify high-emitting vehicles and mitigate their impacts on air quality and climate. I/M programs have been traditionally ranked superior among... Motor vehicle inspection and maintenance (I/M) programs are designed to identify high-emitting vehicles and mitigate their impacts on air quality and climate. I/M programs have been traditionally ranked superior among various vehicle emission control measures by the results of cost-benefit analysis, based on the assumption that these programs will achieve the targeted emission reduction outcomes. However, the actual effects of I/M programs may be greatly uncertain and when this uncertainty is taken into account, these programs may become suboptimal. This study develops a new a cost-benefit analysis framework that links various program design consideration, such as program participation rate, identification rate and effective repair rate, to the public health benefits as well as costs of the programs. This framework helps decision makers to investigate minimum implementation requirements that at least ensure the benefits are greater than the costs of implementing the programs in order to improve the overall effectiveness of the I/M programs. To illustrate the applications of the framework, it was applied to a particulate matter oriented I/M program targeting all diesel-fueled vehicles in the city of Bangkok, Thailand, a large metropolitan area that has been suffering from severe ambient PM pollution mainly attributable to its wide use of diesel-fueled vehicles and motorcycles. It was found that the health benefits achieved from the program are sensitive to several key program design elements, including participation rate and problem vehicle identification rate, fraction of effective repairs and illegal operation rate. Other variables, such as the testing cut-points and vehicle population growth rate, only have modest effects on the overall emission reduction and consequent health benefits. Overall, the performance of multiple variables associated with I/M program design needs to be improved simultaneous in order to achieve the targeted benefits of the program. 展开更多
关键词 INSPECTION and Maintenance PROGRAMS cost-benefit analysis EFFECTIVENESS PROGRAM Design
下载PDF
Cost-benefit Analysis of Scale Pig Breeding in Shandong Province Based on Modified Entropy Weight-TOPSIS Model
11
作者 Yuanyuan ZHANG Shimin SUN 《Asian Agricultural Research》 2014年第8期21-25,共5页
According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding ... According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding in Shandong Province from the perspective of comparing it with that of the entire country and 9 other main pig producing areas. The results show that compared with the national average,the cost-benefit ratio of small scale pig breeding in Shandong Province is lower,while the cost-benefit ratio of medium scale and large scale pig breeding is significantly improved; the cost-benefit ratio of small scale pig breeding in Shandong Province is basically the same as that in 9 other main pig producing areas,while the cost-benefit ratio of medium scale and large scale pig breeding is higher; the output value of main products and the purchase price of piglet are two major bottlenecks restricting the cost-benefit improvement of scale pig breeding in Shandong Province. 展开更多
关键词 PIG SCALE BREEDING cost-benefit analysis TOPSIS mo
下载PDF
Comparative analysis of perpetual pavement structures based on pavement performance and life cycle cost 被引量:3
12
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
下载PDF
Cost-effectiveness analysis of treatments for metastatic castration resistant prostate cancer 被引量:6
13
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
下载PDF
Competitive analysis of price online inventory problem with cost function 被引量:1
14
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
下载PDF
Cost analysis and outcomes of simple elbow dislocations 被引量:1
15
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
下载PDF
Comparison of School Building Construction Costs Estimation Methods Using Regression Analysis, Neural Network, and Support Vector Machine 被引量:2
16
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
下载PDF
Economic Viability of Smallholder Agroforestry and Beekeeping Projects in Uluguru Mountains, Tanzania: A Cost Benefit Analysis 被引量:2
17
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
下载PDF
Modeling Anthrax with Optimal Control and Cost Effectiveness Analysis 被引量:1
18
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
下载PDF
Optimization of Evidence Analysis Cost Using Arbitrary Re-Sampling Techniques for Sample Influx into Forensic Science Laboratory 被引量:1
19
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
下载PDF
AIDS Treatments Efficiency Analysis Based on Cost Efficiency Data Envelopment Analysis Model 被引量:1
20
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
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部