Presently, owners are interested in evaluating the feasibility of investing in the construction of new building projects based on cost and time constraints. They need to therefore have an idea about the project construction costs, the time required to finish construction of a project in its conceptual phase, and about the implementation of feasibility study. Because due to associated risks, construction cost estimates and schedules are vital to any project. The research’s objective is to develop a methodology that can be used to create an integrated computer model that helps owners and designers generate construction cost estimates, and derive the baseline schedule for any proposed building project at its feasibility stage. All the relevant data used within the model is collected from the literature and is stored in comprehensive databases designed for this purpose. The data is based on 2011 RSMeans publications and consist of around 4,000 previously constructed projects. The model is developed in a Microsoft environment using Microsoft Excel 2007 and Microsoft Project 2007. This model uses deterministic and stochastic approaches to execute all necessary calculations for the conceptual cost estimate and baseline schedule. A deterministic approach relies on realistic data while a stochastic one relies on incorporating the uncertainty and risk available in calculating the cost and duration of any construction building project. The model is user friendly, flexible and executes all the necessary calculations quickly. The successful development of the model would help owners and investors identify the cost and baseline schedule of proposed projects at the early stages of the project life, so that they have an idea of the budget required for construction and the time needed to recover their investment.

It has been shown that there exists a correlation between the cost of construction of elementary schools and the project delivery systems. Previous research showed that Competitive Sealed proposal contract method of construction is $4000 cheaper than the Construction Manager at Risk method of construction per student for elementary school construction in Texas. This research investigates the elements causing construction cost variation in elementary schools of Texas by comparing and contrasting the two forms of contract documents, CSP and CMR. Two schools were selected for the study, although the schools are technically in different regions of Texas, the geological record suggests that there is not much difference in the techniques used for foundation construction and hence a reasonable comparison is possible. A comparison was completed of the contract documents for two elementary schools. School A was built using CSP and School B using CMR. The two schools were built for about $13000 per student in line with A. N. Reinisch’s findings for CSP contracts in Texas, but not CMR average costs. The two ISD’s who supplied the documents were clearly concerned at cost control and appear to have managed this process. The earlier findings of a cost difference between CSP and CMR are not overturned by this study. Future studies involving a greater number of schools and the development of a central database are recommended.

Presently, owners are interested in evaluating the feasibility of investing in the construction of new building projects based on cost and time constraints. They need to therefore have an idea about the project construction costs, the time required to finish construction of a project in its conceptual phase, and about the implementation of feasibility study. Because due to associated risks, construction cost estimates and schedules are vital to any project. The research’s objective is to develop a methodology that can be used to create an integrated computer model that helps owners and designers generate construction cost estimates, and derive the baseline schedule for any proposed building project at its feasibility stage. All the relevant data used within the model is collected from the literature and is stored in comprehensive databases designed for this purpose. The data is based on 2011 RSMeans publications and consist of around 4,000 previously constructed projects. The model is developed in a Microsoft environment using Microsoft Excel 2007 and Microsoft Project 2007. This model uses deterministic and stochastic approaches to execute all necessary calculations for the conceptual cost estimate and baseline schedule. A deterministic approach relies on realistic data while a stochastic one relies on incorporating the uncertainty and risk available in calculating the cost and duration of any construction building project. The model is user friendly, flexible and executes all the necessary calculations quickly. The successful development of the model would help owners and investors identify the cost and baseline schedule of proposed projects at the early stages of the project life, so that they have an idea of the budget required for construction and the time needed to recover their investment.

Energy and cost performance optimization for commercial building system design is growing in popularity, but it is often criticized for its time consuming process. Moreover, the current process lacks integration, which not only affects time performance, but also investors’ confidence in the predicted performance of the generated design. Such barriers keep building owners and design teams from embracing life cycle cost consideration. This thesis proposes a computationally efficient design optimization platform to improve the time performance and to streamline the workflow in an integrated multi-objective building system design optimization process. First, building system cost estimation is typically completed through a building information model based quantity take-off process, which does not provide sufficient design decision support features in the design process. To remedy this issue, an automatic cost estimation framework that integrates EnergyPlus with an external database to perform building systems’ capital and operation costs is proposed. Optimization, typically used for building system design selection, requires a large amount of computational time. The optimization process evaluates building envelope, electrical and HVAC systems in an integrated system not only to explore the cost-saving potential from a single high performance system, but also the interrelated effects among different systems. An innovative optimization strategy that integrates machine learning techniques with a conventional evolutionary algorithm is proposed. This strategy can reduce run time and improve the quality of the solutions. Lastly, developing baseline energy models typically takes days or weeks depending on the scale of the design. An automated system for generating baseline energy model according to ANSI/ASHRAE/IESNA Standard 90.1 performance rating method is thus proposed to provide a quick appraisal of optimal designs in comparison with the baseline energy requirements. The main contribution of this thesis is the development of a new design optimization platform to expedite the conventional decision making process. The platform integrates three systems: (1) cost estimation, (2) optimization and (3) benchmark comparison for minimizing the first cost and energy operation costs. This allows designers to confidently select an optimal design with high performance building systems by making a comparison with the minimum energy baseline set by standards in the building industry. Two commercial buildings are selected as case studies to demonstrate the effectiveness of this platform. One building is the Center for Sustainable Landscapes in Pittsburgh, PA. This case study is used as a new construction project. With 54 million possible design solutions, the platform is able to identify optimal designs in four hours. Some of the design solutions not only save the operation costs by up to 23% compared to the ASHRAE baseline design, but also reduce the capital cost ranging from 5% to 23%. Also, compared with the ASHRAE baseline design, one design solution demonstrates that the high investment of a product, building integrative photovoltaic (BiPV) system, can be justified through the integrative design optimization approach by the lower operation costs (20%) as well as the lower capital cost (12%). The second building is the One Montgomery Plaza, a large office building in Norristown, PA. This case study focuses on using the platform for a retrofit project. The calibrated energy model requires one hour to complete the simulation. There are 4000 possible design solutions proposed and the platform is able to find the optimal design solution in around 50 hours. Similarly, the results indicate that up to 25% capital cost can be saved with $1.7 million less operation costs in 25 years, compare to the ASHRAE baseline design.

Notorious for its high poverty levels and low socio-economic status, the Navajo Nation’s socio-economic well-being is hindered greatly in part by the lack of an adequate potable water infrastructure which has resulted in health disparities and has attributed to stunted economic growth within the Nation. Large candidate regional water transmission pipelines projects aimed to meet these needs have been identified. With capital costs exceeding their fiscal capability, decision-makers must choose projects that generate the most bang for the buck. To address these challenges, three (3) interconnected planning tools have been developed: (1) a water pipe installation construction cost estimation model (WaterCOSTE) to improve the accuracy of capital cost estimates; (2) a hydraulic optimization model (WaterTRANS) that improves design efficiency for branched water transmission systems; and (3) a decision support system (DSS) that allows candidate water transmission projects to be ranked while considering economic development, health improvement and environmental protection objectives. Estimates derived from WaterCOSTE are used as input into WaterTRANS to find least-cost system designs. The system costs along with other project data are then input into the DSS to determine project rankings. To demonstrate how the DSS can be used and applied, two candidate projects on the Navajo Nation are evaluated. The tools developed will enable decision-makers to improve planning processes and make wiser investment decisions that will lead to expanding the water infrastructure coverage and living conditions on the Navajo Nation.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-07-27T12:14:16Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Tese Doutorado Hiram Falcão.pdf: 1589850 bytes, checksum: c86ffb35f5d0263dbd80e96c156b8065 (MD5) / Made available in DSpace on 2017-07-27T12:14:16Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Tese Doutorado Hiram Falcão.pdf: 1589850 bytes, checksum: c86ffb35f5d0263dbd80e96c156b8065 (MD5) Previous issue date: 2016-02-24 / CAPES / Para o estabelecimento de populações vegetais em ambientes que são heterogêneos no tempo e no espaço, como florestas que passam por processo de regeneração natural, é fundamental a capacidade de apresentar respostas plásticas em atributos funcionais foliares em resposta às variações ambientais. Plantas pioneiras apresentam estratégias ecofisiológicas distintas de plantas de estádios sucessionais tardios, ocupando posições opostas no espectro de economia foliar. No entanto algumas plantas conseguem se estabelecer, ao mesmo tempo, em áreas em diferentes momentos do processo sucessional. Dessa forma, o presente trabalho teve como objetivo avaliar a variação nos atributos funcionais de três espécies de diferentes hábitos, numa cronosequência (inicial (22 anos), intermediária (44 anos), e tardia (+ 60 anos)) de floresta tropical sazonalmente seca em três estações chuvosas consecutivas. As espécies selecionadas foram: Poincianella pyramidalis (Tul.) L.P. Queiroz (Fabaceae), arbórea; Hyptis suaveolens (L.) Poit. (Lamiaceae), herbácea; e Sida galheirensis Ulbr. (Malvaceae), subarbustiva. As duas primeiras são encontradas nos três estádios sucessionais, e a última apenas nos estádios inicial e tardio. Todas as coletas foram realizadas no período chuvoso, no mês de abril, entre os anos de 2012 e 2015. Foram mensuradas as trocas gasosas, o potencial hídrico foliar, o conteúdo e a eficiência no uso dos nutrientes, a área foliar específica, o conteúdo de compostos fenólicos, o custo de construção foliar e o tempo de compensação. As respostas ecofisiológicas das plantas foram influenciadas tanto pelo estádio sucessional quanto pela precipitação entre os anos. De um modo geral, as plantas do estádio tardio apresentaram maiores taxas de trocas gasosas, potencial hídrico, eficiência no uso dos nutrientes e investimento em defesa, especialmente em 2014, o ano mais chuvoso. Além disso, um maior custo de construção foliar e um menor tempo de compensação foram observados nas plantas da área tardia, evidenciando que em áreas preservadas as plantas são mais eficientes no uso da energia. No entanto a variação nos atributos foliares foi mais intensa entre os anos de coleta. Dentre os atributos funcionais, o potencial hídrico apresentou a maior capacidade de aclimatação à variação ambiental, seguido da eficiência no uso dos nutrientes e da área foliar específica. O atributo com a menor capacidade de resposta plástica foi o custo de construção foliar. No entanto esse atributo foi mostrou-se como um dos mais importantes na classificação das plantas de acordo com o estádio sucessional. Os resultados mostram que a água é o principal filtro ambiental que coordena as respostas ecofisiológicas na floresta tropical sazonalmente seca brasileira. No entanto as diferentes espécies captam e utilizam a água disponível de forma distinta, evidenciando uma diferenciação de nicho com relação ao uso da água. A variação nos atributos funcionais em função do estádio sucessional sugere que as espécies analisadas têm a capacidade de ajustar o seu espectro de economia foliar, utilizando-se de estratégia de captação ou de conservação de recursos de acordo com as exigências do ambiente. / For establishing plant populations in environments that are heterogeneous in time and space, as forests that pass through natural regeneration process, it is essential the ability to present plastic responses in leaf functional traits in response to environmental variations. Pioneer plants have different ecophysiological strategies in comparison plants of late successional stages, occupying opposite positions in the leaf economics spectrum. However some plants can be established, at the same time, in areas at different stages in succession process. Thus, this study aimed to evaluate the changes in the functional attributes of three species of different habits, in a chronosequence (early (22 years), intermediate (44 years) and late ( + 60 years)) of a seasonally tropical dry forest in three consecutive rainy seasons. The species selected were: Poincianella pyramidalis (Tul.) L.P. Queiroz (Fabaceae), a tree; Hyptis Suaveolens (L.) Poit. (Lamiaceae), a herb; and Sida galheirensis Ulbr. (Malvaceae), a subshrub. The first two are found in the three successional stages, and the last one only in the early and late stages. All samples were collected in the rainy season, in April, between the years 2012 and 2015. The gas exchange, leaf water potential, the content and the nutrient use efficiencies, specific leaf area, the content of phenolics, the leaf construction cost and payback time, were measured. Ecophysiological responses of plants were influenced both by the successional stage as the rainfall between years. In general, plants from late stage had higher rates of gas exchange, leaf water potential, nutrients use efficiency and investment in defense, especially in 2014, the wettest year. Furthermore, a higher leaf construction cost and a shorter payback time were observed in late area, showing that, in preserved areas, plants are more efficient in energy use. However the variation in leaf traits was more intense between the years of collection. Among the functional traits, the water potential presented the highest acclimatization capacity to environmental variation, followed by the nutrient use efficiencies and specific leaf area. The leaf trait with the lowest plastic response was the leaf construction cost. However, this trait was one of the most important in classifying the plants according to successional stage. The results showed that water is the main environmental filter that coordinates the ecophysiological responses in the Brazilian seasonally tropical dry forest. However the different species capture and utilize the available water separately, showing a niche differentiation related to water use. The variation in functional traits as a function of the succession stages, suggests that the species in this study have the ability to adjust its leaf economics spectrum economy, by using a resource capture or a conservative strategy according to the requirements of the environment.

No description available.

Thesis. 1976. M.S.--Massachusetts Institute of Technology. Alfred P. Sloan School of Management. / Microfiche copy available in Archives and Dewey. / Bibliography: leaves 135-138. / M.S.

Construction cost estimating is essential for all of the stakeholders of a construction project from the beginning stage to the end. At early stages of a construction project, the design information and scope definition are very limited, hence / during conceptual (early) cost estimation, achieving high accuracy is very difficult. The level of uncertainty included in the cost estimations should be emphasized for making correct decisions throughout the dynamic stages of construction project management process, especially during early stages. By using range estimating, the level of uncertainties can be identified in cost estimations. This study represents integrations of parametric and probabilistic cost estimation techniques in a comparative base. Combinations of regression analysis, neural networks, case &ndash / based reasoning and bootstrap method are proposed for the conceptual (early) range cost estimations of mass housing projects. Practical methods for early range cost estimation of mass housing projects are provided for construction project management professionals. The methods are applied using bid offers of a Turkish contractor given for 41 mass housing projects. The owner of all projects is Housing Development Administration of Turkey (TOKI). The mass housing projects of TOKI are generally a mix of apartment blocks, social, health and educational facilities, and some projects may also have mosques. Results of the three different approaches are compared for predictive accuracy and predictive variability, and suggestions for early range cost estimation of construction projects are made.

La realidad en el sector construcción en el país mantiene déficit en términos económicos y de plazo. Este es el reflejo de las malas prácticas que se aplican en nuestro país por errores en la gestión de los proyectos y sobre todo, por la resistencia al cambio cultural a nuevas metodologías. El TVD es una metodología con enfoque de gestión Lean que se viene aplicando desde el 2007 en proyectos de gran envergadura como colegios y hospitales en Estados Unidos, dando como resultados incrementos en la rentabilidad manteniendo la calidad y tiempos del proyecto, respetando un costo objetivo o un costo meta. En la presente tesis implementaremos esta metodología (TVD) dentro de un proyecto inmobiliario en el segmento Lima Centro que involucra a los distritos de Breña, Cercado de lima, La Victoria y Rímac. Dicha metodología se implementa durante la etapa planificación y diseño, que según el TVD son etapas pilares fundamentales para poder desarrollar con éxito un proyecto, en el cual seguiremos los pasos necesarios para poder cumplir con los requerimientos del cliente. Junto con otras herramientas tales como Lean Design y Project Definition, potenciaremos y optimizaremos los procesos con lo que lograremos mejores resultados en la rentabilidad del proyecto y alcanzar las ganancias requeridas por el cliente. Para consolidar esta metodología, se implementará el cálculo del costo admisible que permitirá incrementar ciertos beneficios a la edificación para mantener la calidad de vida de los usuarios. / The construction industry in Peru keeps having a deficit in terms of money and time. This is because of the common habits when planning a new project and especially of the cultural resistance to new methodologies due the high risk that they imply. Nowadays, the sale of apartments of the real estate sector shows a shortage after the times of the Real Estate Boom which influenced the profitability of this type of projects and the country’s economic. The Target Value Design is Lean methodology that has been applied in large-scale projects of the United States of America since 2007 such as high schools and hospitals. The results for these projects demonstrate the upturn in terms of profit, quality and time of the project respecting a target cost. In this investigation, TVD will be applied in a real estate project in Peru focusing on the Design phase which is the main stage if we want to success using it. We will follow the steps in order to reach the client’s requirements using also the Lean Design and Project Definition tools for enhancing and optimizing the methodology. Thus, the profitability will raise and the good will increase. Finally, the methodology will be consolidated when implementing the allowable cost. This cost will allow the augmentation of other kind of benefits for the building so that we can maintain users’ quality of living. / Tesis