Supplier Selection for Global Service Providers: a Decision Support System

In this paper, we develop a decision support system (DSS) aimed at solving a real-world supplier selection problem (SSP) for a global service provider (GSP) operating in the facility management industry. The GSP provides its customers with facility management services, which are subcontracted to external suppliers selected on the basis of multiple criteria, like economic soundness, quality of service, capacity, and closeness. The SSP is formulated as a multi-objective generalized assignment problem, where the quality and the closeness of the selected suppliers are maximized, whereas a penalty produced by overcapacity assignments is minimized. The quality of each supplier is computed by applying a weighted sum method, resulting from a multi criteria decision analysis in which the criteria weights are determined through an Analytic Hierarchy Process. The DSS is developed using a modular architecture with a relational database, a supplier evaluator, and a simulator, as well as an additional user-friendly interface. The simulator relies on a rolling horizon algorithm and three alternative configurations to assign contracts to suppliers. The effectiveness of the DSS is assessed by means of extensive computational experiments on historical data from the GSP. The results show a significant average improvement of at least 25% in terms of objective function value compared to the solution adopted by the company and prove the advantage of using the DSS

Modeling Portfolio Loss by Interval Distributions

Models for a continuous risk outcome has a wide application in portfolio risk management and capital allocation. We introduce a family of interval distributions based on variable transformations. Densities for these distributions are provided. Models with a random effect, targeting a continuous risk outcome, can then be fitted by maximum likelihood approaches assuming an interval distribution. Given fixed effects, regression function can be estimated and derived accordingly when required. This provides an alternative regression tool to the fraction response model and Beta regression model

Fuzzy Analytic Hierarchy Process Utilization in Government Projects : A Systematic Review of Implementation Processes

Uncertain assessments challenge the aggregation of expert knowledge in the field of decision-making. Valuable, yet sometimes hesitant, insight of expert decision makers needs to be converted into numerically comparative form in the age of information management. . Fuzzy Analytic Hierarchy Process (FAHP) enables the comparison of decision elements through expert judgements, even when the information at hand is uncertain. The present study explores Fuzzy Analytic Hierarchy Process (FAHP) implementation in government projects in a systematic literature review. Theoretical framework for Analytic Hierarchy Process (AHP), Fuzzy Set Theory (FST) and their combination, namely Fuzzy Analytic Hierarchy Process (FAHP) is provided. The systematic literature review categorizes research results under three categories and examines each paper by utilizing review questions. Three main application purposes rise from the literature review; policy planning and assessment, project selection and project and performance evaluation. Overall implementation processes of the three application areas are discussed. The conclusion provides comprehensive evaluation of the approach and considerations for practitioners.Asiantuntijanäkemysten epävarmuus vaikeuttaa tiedon keräämistä päätöksenteossa. Päätöksentekoprosessin kannalta arvokkaat, vaikkakin joskus epävarmat, asiantuntijanäkemykset tulee voida muuttaa numerollisesti vertailtavaan muotoon tietojohtamisen aikakautena. Sumea Analyyttinen Hierarkiaprosessi mahdollistaa päätöksenteossa käytettävien elementtien vertailun asiantuntija-arviointien avulla, jopa silloin kun käytettävissä oleva tieto on epävarmaa. Opinnäytetyössä tutkitaan systemaattisen kirjallisuuskatsauksen keinoin Sumean Analyyttisen Hierarkiaprosessin, eng. Fuzzy Analytic Hierarchy Process (FAHP), implementointia julkishallinnon hankkeissa. Tutkimus sisältää teoreettisen viitekehyksen Analyyttisen Hierarkiaprosessin, Sumean joukko-opin, eng. Fuzzy Set Theory (FST) ja niiden yhdistelmän, Sumean Analyyttisen Hierarkiaprosessin, eng. Fuzzy Analytic Hierarchy Process (FAHP), ymmärtämisen tueksi. Systemaattisen kirjallisuuskatsauksen myötä valittu aineisto luokitellaan kolmeen kategoriaan ja jokaista tutkimusta tarkastellaan ennalta määrättyjen kysymysten avulla. Systemaattisen kirjallisuuskatsaukseen myötä valittujen tutkimusten kolme olennaisinta käyttötarkoitusta ovat; käytännön suunnittelu ja arviointi, hankevalinta sekä hankkeiden ja suoritusten arviointi. Aineiston luokittelun jälkeen tutkimus etenee tarkastelemaan erilaisiin käyttötarkoituksiin suunnattujen Sumean Analyyttisen Hierarkiaprosessi -metodin implementointiprosesseja. Johtopäätös -osio tarjoaa pohdintaa ja huomioita siitä, miten päätöksentekijät voivat suhtautua Sumean Analyyttisen Hierarkiaprosessin hyödyntämiseen julkishankkeiden yhteydessä

The load planning problem for double-stack intermodal trains

Les trains qui transportent des conteneurs empilés (en deux niveaux) sont un élément important du reseau de transport nord-americain. Le probleme de chargement des wagons correspond un probleme operationnel d'utilisation rencontre dans les terminaux ferroviaires. Elle consiste optimiser l’affectation des conteneurs des emplacements spécifiques sur les wagons. Ce mémoire est centré sur un article scientifique traitant le chargement optimal publié dans le Journal Européen de Recherche Opérationnelle (Volume 267, Numéro 1, Pages 107-119, 2018). Nous avons formule un modele lineaire en nombres entiers (ILP) et apporte un certain nombre de contributions. Premierement, nous avons proposé une méthodologie générale qui peut traiter des wagons double ou simple empilement avec des «patrons» de chargement arbitraires. Les les patrons tiennent un compte des dépendances de chargement entre les plateformes sur un wagon donne. Deuxiemement, nous avons modéliser les restrictions du centre de gravité (COG), les regles d’empilement et un nombre de restrictions techniques de chargement associees certains types de conteneurs et / ou de marchandises. Les resultats montrent que nous pouvons resoudre des instances de taille realiste dans un d´elai raisonnable en utilisant un solveur ILP commercial et nous illustrons que le fait de ne pas tenir compte de la correspondance conteneurs-wagons ainsi que des restrictions COG peut conduire une surestimation de la capacité disponible.Double-stack trains are an important component of the railroad transport network for containerized cargo in specific markets such as North America. The load planning problem embodies an operational problem commonly faced in rail terminals by operators. It consists in optimizing the assignment of containers to specific locations on the train. The work in this thesis is centered around a scientific paper on the optimization on load planning problem for double stack-trains, published in the European Journal of Operation Research (Volume 267, Issue 1, Pages 1-398) on 16 May 2018. In the paper, we formulated an ILP model and made a number of contributions. First, we proposed a general methodology that can deal with double- or single-stack railcars with arbitrary loading patterns. The patterns account for loading dependencies between the platforms on a given railcar. Second, we modeled Center of gravity (COG) restrictions, stacking rules and a number of technical loading restrictions associated with certain types of containers and/or goods. Results show that we can solve realistic size instances in reasonable time using a commercial ILP solver and we illustrate that failing to account for containers-to-cars matching as well as COG restrictions may lead to an overestimation of the available train capacity

Improving MSMEs’ access to start-up financing in ASEAN countries

Lack of access to finance constitutes a major setback to the development of the MSME sector in ASEAN countries. MSMEs are confronted with stringent funding constraints in traditional lending and capital markets, in particular at the early stages of their activity. Demand and supply of capital to MSMEs thus entails more complex issues compared to the larger firms. This paper presents a number of policy actions that have the potential to mitigate the financing challenges faced by MSMEs in ASEAN at the start-up stage by enhancing the potential of alternative funding sources such as business angel investment, crowdfunding, venture capital investment and SME stock markets

Modelo matemático para alocação de especialidades cirúrgicas com prioridades hierarquizadas por meio do Analitycal Hierarchy Process (AHP)

Orientador: Prof. José Eduardo Pécora Junior, Ph.D.Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia de Produção. Defesa : Curitiba, 28/02/2019Inclui referências: p.63-67Área de concentração: Pesquisa OperacionalResumo: O agendamento de cirurgias eletivas às salas cirúrgicas é um processo que tem como objetivo determinar os horários de início de cada cirurgia e qual especialidade deve ser alocada à sala, considerando todas as restrições de recursos disponíveis para garantir fluxo nas atividades dos centros cirúrgicos. No entanto, este processo é passível de imprevistos os quais acabam gerando cancelamentos de horários já programados. Diante disso, surge a seguinte pergunta: qual especialidade alocar para este horário? Este trabalho tem como objetivo propor um modelo de priorização de especialidades cirúrgicas por meio do método Analytic Hierarchy Process (AHP). Ainda, utilizar os pesos atribuídos a cada especialidade em um modelo matemático para apoiar a decisão de escolha de qual especialidade cirúrgica alocar para uma ou mais salas vagas. Uma revisão sistemática de literatura foi apresentada para buscar respostas de como determinar os critérios de priorização das especialidades disponíveis e sobre qual abordagem matemática utilizar para o modelo. Com isso, é proposto o método AHP combinado com um modelo matemático de programação linear inteira para apoiar a decisão de alocação da especialidade à sala dado que um ou mais horários foram disponibilizados por cancelamento. Por fim, uma aplicação do modelo proposto é realizada nas dependências do centro cirúrgico do Hospital de Clínicas da Universidade Federal do Paraná. Palavras-chave: Centro Cirúrgico, Critérios de Seleção de Especialidades Cirúrgicas, Modelo Matemático, AHP.Abstract: The scheduling of elective surgeries to surgical rooms is a process that aims to determine the opening times of each surgery and which specialty should be allocated to the room, considering all the restrictions of available resources to guarantee flow in the surgical centers activities. However, this process is subject to unforeseen events which end up generating cancellations of schedules already scheduled. Given this, the question arises: which specialty to allocate for this time? This work aims to propose a prioritization model of surgical specialties through the Analytic Hierarchy Process (AHP) method. Also, use the weights assigned to each specialty in a mathematical model to support the decision of choosing which surgical specialty to allocate to one or more vacant rooms. A systematic literature review was presented to seek answers on how to determine the prioritization criteria of the specialties available and on which mathematical approach to use for the model. Thus, the AHP method combined with a mathematical model of integer linear programming is proposed to support the decision to allocate the specialty to the room given that one or more schedules were made available by cancellation. Finally, an application of the proposed model is performed in the surgical center of the Hospital de Clínicas of the Federal University of Paraná. Key-words: Surgerical Center, Selection Criteria for Surgical Specialties, Mathematical Model, Optimizatio

Optimización de los costos de operación de una empresa de renta de vehículos en Colombia

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