There is a growing interest in electronic auctions in the literature. Many researchers work on the single attribute version of the problem. Multi-attribute version of the problem is more realistic. However, this brings a substantial difficulty in solving the problem. In order to overcome the computational difficulties, we develop an Evolutionary Algorithm (EA) for the case of multi-attribute multi-item reverse auctions. We generate the whole Pareto front using the EA. We also develop heuristic procedures to find several good initial solutions and insert those in the initial population of the EA. We test the EA on a number of randomly generated problems and compare the results with the true Pareto optimal front obtained by solving a series of integer programs. We also develop an exact interactive approach that provides aid both to the buyer and the sellers for a multi-attribute single item multi round reverse auction. The buyer decides on the provisional winner at each round. Then the approach provides support in terms of all attributes to each seller to be competitive in the next round of the auction.

In this study, we address the long-term project pricing problem for a company that operates in the defense industry. The pricing problem is a bid project pricing problem which includes various technical and financial uncertainties, such as estimations of workhour content of the project and exchange &amp / inflation rates. We propose a Robust Optimization (RO) approach that can deal with the uncertainties during the project lifecycle through the identification of several discrete scenarios. The bid project&rsquo / s performance measures, other than the monetary measures, for R&amp / D projects are identified and the problem is formulated as a multi-attribute utility project pricing problem. In our RO approach, the bid pricing problem is decomposed into two parts which are v solved sequentially: the Penalty-Model, and the RO model. In the Penalty-Model, penalty costs for the possible violations in the company&rsquo / s workforce level due to the bid project&rsquo / s workhour requirements are determined. Then the RO model searches for the optimum bid price by considering the penalty cost from the Penalty-Model, the bid project&rsquo / s performance measures, the probability of winning the bid for a given bid price and the deviations in the bid project&rsquo / s cost. Especially for the R&amp / D type projects, the model tends to place lower bid prices in the expected value solutions in order to win the bid. Thus, due to the possible deviations in the project cost, R&amp / D projects have a high probability of suffering from a financial loss in the expected value solutions. However, the robust solutions provide results which are more aware of the deviations in the bid project&rsquo / s cost and thus eliminate the financial risks by making a tradeoff between the bid project&rsquo / s benefits, probability of winning the bid and the financial loss risk. Results for the probability of winning in the robust solutions are observed to be lower than the expected value solutions, whereas expected value solutions have higher probabilities of suffering from a financial loss.

Title from PDF of title page. / Document formatted into pages; contains 117 pages. / Thesis (M.S.C.S.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: The modern economy includes a variety of markets, and the Internet has opened opportunities for efficient on-line trading. Researchers have developed algorithms for various auctions, which have become a popular means for on-line sales. They have also designed algorithms for exchange-based markets, similar to the traditional stock exchange, which support fast-paced trading of rigidly standardized securities. In contrast, there has been little work on exchanges for complex nonstandard commodities, such as used cars or collectible stamps. We propose a formal model for trading of complex goods, and present an automated exchange for a limited version of this model. The exchange allows the traders to describe commodities by multiple attributes; for example, a car buyer may specify a model, options, color, and other desirable properties. / ABSTRACT: Furthermore, a trader may enter constraints on the acceptable items rather than a specific item; for example, a buyer may look for any car that satisfies certain constraints, rather than for one particular vehicle. We present an extensive empirical evaluation of the implemented exchange, using artificial data, and then give results for two real-world markets, used cars and commercial paper. The experiments show that the system supports markets with up to 260,000 orders, and generates one hundred to one thousand trades per second. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

Conventionally, the focus during supplier evaluation has been to assess cost, quality and delivery effectiveness due to their impact on profitability. In recent years, there has been increased emphasis on promoting more sustainable business practices that focus on reducing environmental impact and improve societal well-being, in addition to economic benefits. However, most of the existing supplier evaluation methods in literature as well as those used by leading companies fall short of comprehensively assessing suppliers from a Triple Bottom Line (TBL) perspective. TBL defined as holistically looking at the economic, environmental, and societal aspects of an entity. This paper presents a review and selection of metrics for economic, environmental and societal sustainability evaluation. In addition, this work proposes a methodology for combining the scores into a comprehensive score that can be used to compare two entities performance relative to the TBL.

Pastatų atnaujinimas (modernizavimas) yra viena iš prioritetinių ES sanglaudos politikos sričių. Augančios energinių išteklių kainos bei higienos normų netenkinanti gyvenamoji, darbo ir poilsio aplinka skatina visuomenę labiau domėtis ir aktyviau dalyvauti pastatų atnaujinimo procese. Disertacijos tikslas – sukurti teorinį pastatų atnaujinimo efektyvumo vertinimo modelį, pagrįstą daugiatiksliais sprendimo priėmimo metodais, bei jį praktiškai pritaikyti naudojant visuomeninės paskirties pastatų tyrimų, atliktų prieš ir po atnaujinimo, rezultatus. Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, literatūros ir šaltinių bei autoriaus publikacijų disertacijos tema sąrašai, santrauka anglų kalba ir trys priedai. Įvade formuluojama problema, aprašomas darbo aktualumas, tyrimų objektas, įvardijamas darbo tikslas bei uždaviniai, pateikiama tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Įvado pabaigoje pristatomos disertacijos tema autoriaus paskelbtos publikacijos ir pranešimai konferencijose bei pateikiama disertacijos struktūra. Pirmasis skyrius yra skirtas literatūros (mokslinių publikacijų ir teisės aktų) analizei. Jame pateiktas statinių klasifikavimas pagal paskirtį ir pastatų atnaujinimą lemiantys veiksniai, atlikta visuomeninės paskirties pastatų atnaujinimo analizė, pateikta daugiatikslio sprendimo priėmimo sąvoka ir daugiatikslių sprendimo priėmimo metodų klasifikacija, aprašytas daugiatikslių metodų pritaikymas... [toliau žr. visą tekstą] / Renovation (modernisation) of buildings is one of the priority areas of EU cohesion policy. Growing prices for energy resources as well as living, working and leisure environments that do not conform to requirements of hygiene norms encourage the public to take more efforts towards participation in the process of building renovation. The dissertation aim to create a theoretical model for the assessment of efficiency of building renovation based on multi-attribute decision making methods and use it in practice with results of investigations made on public buildings (kindergartens) before and after renovation. The dissertation comprises an introduction, three chapters, general conclusions, lists of literature, resources and publications of the author on the topic of the dissertation, abstract in English and three annexes. The introduction specifies the problem, describes the relevance of the paper, the research object, aim and objectives as well as methodology of the research, its novelty, practical significance of results, and defended statements. Finally, it lists publications and conference presentations produced by the author on the topic of the dissertation and presents its structure. Chapter one is dedicated for literature (scientific publications and legislative acts) analysis. It provides classification of structures according to their intended use and lists factors determining renovation of buildings; describes the analysis into renovation of public buildings; presents... [to full text]

Thesis (MScEng (Industrial Engineering))--Stellenbosch University, 2008. / Passenger cars are either imported to or assembled in South Africa, and then distributed to the customer. An important part of the supply chain is formed by the auto carrier companies who do this distribution. The basis of this thesis is a study that was executed in collaboration with a South African auto carrier company, and the objective was to improve the long-distance auto carrier fleet management through improved tactical operational policies. These policies focus on application of the fleet by assigning transportation vehicles to routes, as well as the business rules that must be followed at pick-up and drop-off locations. Several rules were developed during this study, which, together with specific transportation vehicle (carriers) assignments, form operational scenarios. The quality of each scenario was evaluated using discrete event simulation over a six month time-span, and considering four decision parameters simultaneously. These parameters are 1) useful kilometres travelled by the long-distance carriers, 2) empty kilometres travelled by the same long-distance carriers, 3) the expected number of cars waiting to be transported and 4) the expected time it takes to deliver a car to its destination. A high level of uncertainty prevails in these transportation operations, while fluctuating demand calls for the dynamic allocation and management of carriers in order to sustain an acceptable service level in a cost-effective manner. The best tactical policies should maximize the number of cars delivered on time at the lowest cost. Major constraints considered are staff- and maintenance schedules. While searching for the best of several scenarios, multiple, conflicting criteria had to be evaluated, as mentioned above. Two multi-criteria decision analysis (MCDA) methods were used namely SAW and TOPSIS, while the Mahalanobis distance method was also applied as an evaluation technique. These methods were used to rank scenarios. Additionally, the application of Portfolio theory and the efficient frontier was investigated for applicability to the problem studied. An analogy to the efficient frontier providing an additional means for scenario selection and evaluation was developed. The result of this study provides the decision maker of the auto carrier company with a tactical decision aid, consisting of the MCDA and Mahalanobis scenario rankings, a cost-benefit graph and a fleet portfolio efficient frontier, to aid long-distance carrier management. Additionally, a sensitivity analysis was also done for strategic planning concerned with the sufficient long-distance carrier fleet size. The first part of this thesis comprises a study of literature in which freight operations, auto carrier studies and the auto carrier context in South Africa are investigated. The problem is formulated and a suitable formulation and solution tool identified. Multi-criteria decision analysis is also investigated in order to enable scenario evaluation. The solution development phase consisted of the simulation model concept development, acquisition of input data, model verification and validation, scenario construction, simulation execution, and analysis of results.

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<p>Online reviews are frequently utilized to determine a product's quality before purchase along with the photographs and one-to-five star ratings. The research addressed the two distinct problems observed in the review systems. </p> <p>First, due to thousands of reviews for a product, the different characteristics of customer evaluations, such as consumer sentiments, cannot be understood by manually reading only a few reviews. Second, from these reviews, it is extremely hard to understand the change in these sentiments and other important product aspects over the years (temporal analysis). To address these problems, the study focused on 2 main research parts.</p> <p>Part one of the research was focused on answering how topic modelling and sentiment analysis can work together to give deeper understanding on attribute-based product review. The second part compared different topic modelling approaches to evaluate the performances and advantages of emerging NLP models. For this purpose, a dataset consisting of 469 publicly accessible Amazon evaluations of the Kindle E-reader and 15,000 reviews of iPhone products was utilized to examine sentiment Analysis and Topic modelling. Latent Dirichlet Allocation topic model and BERTopic topic model were used to perform topic modelling and to acquire the diverse topics of concern. Sentiment Analysis was carried out to better understand each topic's positive and negative tones. Topic analysis of Kindle user evaluations revealed the following major themes: (a) leisure consumption, (b) utility as a gift, (c) pricing, (d) parental control, (e) reliability and durability, and (f) charging. While the main themes emerged from the analysis of iPhone reviews depended on the model and year of the device, some themes were found to be consistent across all the iPhone models including (a) Apple vs Android (b) utility as gift and (c) service. The study's approach helped to analyze customer reviews for any product, and the study results provided a deeper understanding of the product's strengths and weaknesses based on a comprehensive analysis of user feedback useful for product makers, retailers, e-commerce platforms, and consumers.</p>

This paper examines the relationship between a multi-attribute attitude model and residential preference as a step towards developing an attitudinal model of housing choice. The use of multi-attribute attitude models, similar to those employed in marketing research, is suggested as a viable means of measuring residential preference, on the basis of measures of individual affect. Conceptual and measurement problems with each component of the suggested model are discussed and two attitude models of residential preference are presented. These models are empirically tested in a pilot study which deals with the housing preferences of a sample of on campus residents at McMaster University. The relationship which is shown to exist between attitude and preference in the pilot study, supports proposals for recommending an attitude model approach to the analysis of housing choice, in a more intensive enquiry. / Thesis / Master of Arts (MA)