957 resultados para Cost Modelling
Resumo:
This research is part of a project whose scope was to investigate the engineering properties of new non-commercial alloy formulations based on the Cu rich corner of the Cu-Fe-Cr ternary system with the primary aim of exploring the development of a new cost-effective high-strength, high-conductivity copper alloy. Promising properties have been measured for the following alloys: Cu-0.7wt%Cr-0.3wt%Fe and Cu-0.7wt%Cr-2.0wt%Fe. This paper reports on the microstructural characterisation of these alloys and discusses the mechanical and electrical properties of these alloys in terms of their microstructure, particularly the formation of precipitates. These alloys have evinced properties that warrant further investigation. Cost modelling has shown that Cu-0.7wt%Cr-0.3wt%Fe is approximately 25% cheaper to produce than commercial Cu-1%Cr. It has also been shown to be more cost efficient on a yield stress and % IACS per dollar basis. The reason for the cost saving is that the Cu-0.7%Cr-0.3%Fe alloy can be made with low carbon ferro-chrome additions as the source of chromium rather than the more expensive Cu-Cr master-alloy. For applications in which cost is one of the primary materials selection criteria, it is envisaged that there would be numerous applications in both cast and wrought form, where the Cu-0.7%Cr-0.3%Fe alloy would be more suitable than Cu-1%Cr. (C) 2001 Kluwer Academic Publishers.
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Background, aim, and scope A coupled Life Cycle Costing and life cycle assessment has been performed for car-bodies of the Korean Tilting Train eXpress (TTX) project using European and Korean databases, with the objective of assessing environmental and cost performance to aid materials and process selection. More specifically, the potential of polymer composite car-body structures for the Korean Tilting Train eXpress (TTX) has been investigated. Materials and methods This assessment includes the cost of both carriage manufacturing and use phases, coupled with the life cycle environmental impacts of all stages from raw material production, through carriage manufacture and use, to end-of-life scenarios. Metallic carriages were compared with two composite options: hybrid steel-composite and full-composite carriages. The total planned production for this regional Korean train was 440 cars, with an annual production volume of 80 cars. Results and discussion The coupled analyses were used to generate plots of cost versus energy consumption and environmental impacts. The results show that the raw material and manufacturing phase costs are approximately half of the total life cycle costs, whilst their environmental impact is relatively insignificant (3-8%). The use phase of the car-body has the largest environmental impact for all scenarios, with near negligible contributions from the other phases. Since steel rail carriages weigh more (27-51%), the use phase cost is correspondingly higher, resulting in both the greatest environmental impact and the highest life cycle cost. Compared to the steel scenario, the hybrid composite variant has a lower life cycle cost (16%) and a lower environmental impact (26%). Though the full composite rail carriage may have the highest manufacturing cost, it results in the lowest total life cycle costs and lowest environmental impacts. Conclusions and recommendations This coupled cost and life cycle assessment showed that the full composite variant was the optimum solution. This case study showed that coupling of technical cost models with life cycle assessment offers an efficient route to accurately evaluate economic and environmental performance in a consistent way.
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Logistiikan kehittämisen merkitys on suuri rakennusalan yritysten kilpailukyvylle. Tutkimuksen kohdeyrityksessä ei tunnettu logistiikkakustannuksia ja tämän takia eri toimitusketjuvaihtoehtojen kustannusvaikutuksia ei voitu vertailla. Ilman kustannustietoja toiminnan kehittäminen ja kilpailukyky kärsivät. Rakentamisen kehittämisen nopein tehostamis- ja kustannussäästöpotentiaali onkin logistiikassa. Tutkimuksen tavoite oli luoda helppokäyttöinen, nopea, ymmärrettävä ja luotettavaa informaatiota tarjoava toimitusketjuratkaisija, jonka avulla voidaan löytää kustannustehokkain toimitusketju projektitietojen perusteella. Alustava mallinnus ja testaus suoritettiin Excel-ohjelmalla. Malli laski logistiset kustannukset kustannustekijäkohtaisesti yhteen huomioiden tutkimuksen rajaukset. Osa rakennusalan tuotteista aiheuttaa huomattavan määrän kokonais- sekä logistisista kustannuksista, kun taas tiettyjen tuotteiden kustannukset ovat vain pieniä. Eri talotyypeille voidaan löytää yleisiä ohjesääntöjä toimitusketjujen käytöstä, mutta työmailla on aina myös tuotteita, jotka kannattaa tuoda joko terminaali- tai suorana toimituksena. Työmaiden olosuhteet ja toimitusmäärät ovatkin varsin ratkaisevassa asemassa toimitustapaa valittaessa. Edellä mainittuja tutkimustuloksia tukivat alan kirjallisuus sekä mallin testaustulokset.
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Työn tavoitteena oli tutkia mekaanisia käsittelylaitteita ja -prosesseja kaupalliselle sekajätteelle ja selvittää mahdollisen laitoshankkeen kannattavuutta case-yritykselle. Jätehuollon yritykset ovat jatkuvan muutoksen alla kasvavien keräys- ja käsittelykustannusten takia, joka vaatii säästöjen etsimistä. Sekajäte sisältää arvokkaita kierrätysraaka-aineita ja näiden erottelu voisi luoda lisäarvoa alentuneina hävityskustannuksina ja lisääntyneinä myyntituottoina. Työssä selvitettiin kaupallisen sekajätteen koostumusta lajittelukokeen ja muiden sekajätetutkimusten avulla. Mekaanisia käsittelylaitteita tutkittiin kirjallisuuden ja case-esimerkkien kautta. Laitoshakkeen kannattavuutta arvioitiin taulukkolaskentamallin avulla. Laitosvaihtoehtoja tarkasteltiin 10-30 tuhannen tonnin kapasiteetin välillä. Laskelmien ja kirjallisuustutkimuksen pohjalta kannattavimpana vaihtoehtona nähtiin SRF kierrätyspolttoainetta valmistava laitos. Kirjallisuustutkimuksen ja case-laitosten pohjalta luotiin kaksi investointiskenaariota, joille laskettiin taulukkolaskentamallin avulla yksikkökustannukset, nettonykyarvot ja sisäiset korot. Kustannusaineisto oli peräisin case-yritykseltä ja muista laitostutkimuksista. Kannattavuuslaskelmien mukaan skenaario 2, jossa SRF-tuotannon lisäksi eroteltaisiin sekalaisia muoveja, on kannattavampi. Skenaarioiden 1 ja 2 kriittiset pisteet olivat noin 15,3 ja 13,6 tuhatta tonnia vuodessa. Kumpikaan skenaarioista ei kuitenkaan ole kannattava case-yrityksen omilla vuotuisilla kuormilla (10 000 tonnia). Lisää käsiteltävää jätettä tulisi hankkia ulkopuolisilta yrityksiltä taloudellisesti edullisen vaakamaksun avulla. Skenaarion 2 ongelmaksi kuitenkin muodostuu sekalaisten muovien poistuminen SRF:n komponenttina, mikä vaikuttaa SRF:n markkinoitavuuteen tehollisen lämpöarvon alenemisen takia.
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Over the past decade there has been significant growth in the facilities management (FM) sector resulting in a diverse and highly competitive marketplace. This marketplace engages contractors, in-house teams, suppliers, consultants and professional institutions. Many of these organisations have had to innovate to differentiate themselves from competitors. The subject of this paper is facilities management innovation. More specifically, it examines the introduction of information technology (IT) to support such innovations. Our understanding of how such innovations are brought about is scant. The intention of this paper is to examine the motivations and factors which have brought about ‘information system’ innovations in the sector based on an examination of a small but diverse collection of case studies. The study specifically considers the route by which the selected innovations came about and the way in which the innovation has diffused throughout the rest of the organisation. The IT innovations identified in case studies include whole life cost modelling, a content management solution, open book partnering, management information portal (fmNet), RFID technology, and capacity and capability planning. Taken together they characterise a sector that is using IT to codify and standardise information such that useful knowledge becomes widely dispersed.
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This paper reviews three different approaches to modelling the cost-effectiveness of schistosomiasis control. Although these approaches vary in their assessment of costs, the major focus of the paper is on the evaluation of effectiveness. The first model presented is a static economic model which assesses effectiveness in terms of the proportion of cases cured. This model is important in highlighting that the optimal choice of chemotherapy regime depends critically on the level of budget constraint, the unit costs of screening and treatment, the rates of compliance with screening and chemotherapy and the prevalence of infection. The limitations of this approach is that it models the cost-effectiveness of only one cycle of treatment, and effectiveness reflects only the immediate impact of treatment. The second model presented is a prevalence-based dynamic model which links prevalence rates from one year to the next, and assesses effectiveness as the proportion of cases prevented. This model was important as it introduced the concept of measuring the long-term impact of control by using a transmission model which can assess reduction in infection through time, but is limited to assessing the impact only on the prevalence of infection. The third approach presented is a theoretical framework which describes the dynamic relationships between infection and morbidity, and which assesses effectiveness in terms of case-years prevented of infection and morbidity. The use of this model in assessing the cost-effectiveness of age-targeted treatment in controlling Schistosoma mansoni is explored in detail, with respect to varying frequencies of treatment and the interaction between drug price and drug efficacy.
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Rapid response to: Ortegón M, Lim S, Chisholm D, Mendis S. Cost effectiveness of strategies to combat cardiovascular disease, diabetes, and tobacco use in sub-Saharan Africa and South East Asia: mathematical modelling study. BMJ. 2012 Mar 2;344:e607. doi: 10.1136/bmj.e607. PMID: 22389337.
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Health care providers, purchasers and policy makers need to make informed decisions regarding the provision of cost-effective care. When a new health care intervention is to be compared with the current standard, an economic evaluation alongside an evaluation of health benefits provides useful information for the decision making process. We consider the information on cost-effectiveness which arises from an individual clinical trial comparing the two interventions. Recent methods for conducting a cost-effectiveness analysis for a clinical trial have focused on the net benefit parameter. The net benefit parameter, a function of costs and health benefits, is positive if the new intervention is cost-effective compared with the standard. In this paper we describe frequentist and Bayesian approaches to cost-effectiveness analysis which have been suggested in the literature and apply them to data from a clinical trial comparing laparoscopic surgery with open mesh surgery for the repair of inguinal hernias. We extend the Bayesian model to allow the total cost to be divided into a number of different components. The advantages and disadvantages of the different approaches are discussed. In January 2001, NICE issued guidance on the type of surgery to be used for inguinal hernia repair. We discuss our example in the light of this information. Copyright © 2003 John Wiley & Sons, Ltd.
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The paper presents the techno-economic modelling of CO2 capture process in coal-fired power plants. An overall model is being developed to compare carbon capture and sequestration options at locations within the UK, and for studies of the sensitivity of the cost of disposal to changes in the major parameters of the most promising solutions identified. Technological options of CO2 capture have been studied and cost estimation relationships (CERs) for the chosen options calculated. Created models are related to the capital, operation and maintenance cost. A total annualised cost of plant electricity output and amount of CO2 avoided have been developed. The influence of interest rates and plant life has been analysed as well. The CERs are included as an integral part of the overall model.
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Objectives To model the impact on chronic disease of a tax on UK food and drink that internalises the wider costs to society of greenhouse gas (GHG) emissions and to estimate the potential revenue. Design An econometric and comparative risk assessment modelling study. Setting The UK. Participants The UK adult population. Interventions Two tax scenarios are modelled: (A) a tax of £2.72/tonne carbon dioxide equivalents (tCO2e)/100 g product applied to all food and drink groups with above average GHG emissions. (B) As with scenario (A) but food groups with emissions below average are subsidised to create a tax neutral scenario. Outcome measures Primary outcomes are change in UK population mortality from chronic diseases following the implementation of each taxation strategy, the change in the UK GHG emissions and the predicted revenue. Secondary outcomes are the changes to the micronutrient composition of the UK diet. Results Scenario (A) results in 7770 (95% credible intervals 7150 to 8390) deaths averted and a reduction in GHG emissions of 18 683 (14 665to 22 889) ktCO2e/year. Estimated annual revenue is £2.02 (£1.98 to £2.06) billion. Scenario (B) results in 2685 (1966 to 3402) extra deaths and a reduction in GHG emissions of 15 228 (11 245to 19 492) ktCO2e/year. Conclusions Incorporating the societal cost of GHG into the price of foods could save 7770 lives in the UK each year, reduce food-related GHG emissions and generate substantial tax revenue. The revenue neutral scenario (B) demonstrates that sustainability and health goals are not always aligned. Future work should focus on investigating the health impact by population subgroup and on designing fiscal strategies to promote both sustainable and healthy diets.
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The application of the Water Framework Directive (WFD) in the European Union (EU) targets certain threshold levels for the concentration of various nutrients, nitrogen and phosphorous being the most important. In the EU, agri-environmental measures constitute a significant component of Pillar 2—Rural Development Policies in both financial and regulatory terms. Environmental measures also are linked to Pillar 1 payments through cross-compliance and the greening proposals. This paper drawing from work carried out in the REFRESH FP7 project aims to show how an INtegrated CAtchment model of plant/soil system dynamics and instream biogeochemical and hydrological dynamics can be used to assess the cost-effectiveness of agri-environmental measures in relation to nutrient concentration targets set by the WFD, especially in the presence of important habitats. We present the procedures (methodological steps, challenges and problems) for assessing the cost-effectiveness of agri-environmental measures at the baseline situation, and climate and land use change scenarios. Furthermore, we present results of an application of this methodology to the Louros watershed in Greece and discuss the likely uses and future extensions of the modelling approach. Finally, we attempt to reveal the importance of this methodology for designing and incorporating alternative environmental practices in Pillar 1 and 2 measures.
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In addition to CO2, the climate impact of aviation is strongly influenced by non-CO2 emissions, such as nitrogen oxides, influencing ozone and methane, and water vapour, which can lead to the formation of persistent contrails in ice-supersaturated regions. Because these non-CO2 emission effects are characterised by a short lifetime, their climate impact largely depends on emission location and time; that is to say, emissions in certain locations (or times) can lead to a greater climate impact (even on the global average) than the same emission in other locations (or times). Avoiding these climate-sensitive regions might thus be beneficial to climate. Here, we describe a modelling chain for investigating this climate impact mitigation option. This modelling chain forms a multi-step modelling approach, starting with the simulation of the fate of emissions released at a certain location and time (time-region grid points). This is performed with the chemistry–climate model EMAC, extended via the two submodels AIRTRAC (V1.0) and CONTRAIL (V1.0), which describe the contribution of emissions to the composition of the atmosphere and to contrail formation, respectively. The impact of emissions from the large number of time-region grid points is efficiently calculated by applying a Lagrangian scheme. EMAC also includes the calculation of radiative impacts, which are, in a second step, the input to climate metric formulas describing the global climate impact of the emission at each time-region grid point. The result of the modelling chain comprises a four-dimensional data set in space and time, which we call climate cost functions and which describes the global climate impact of an emission at each grid point and each point in time. In a third step, these climate cost functions are used in an air traffic simulator (SAAM) coupled to an emission tool (AEM) to optimise aircraft trajectories for the North Atlantic region. Here, we describe the details of this new modelling approach and show some example results. A number of sensitivity analyses are performed to motivate the settings of individual parameters. A stepwise sanity check of the results of the modelling chain is undertaken to demonstrate the plausibility of the climate cost functions.