951 research outputs found

    Application of Multicriteria Decision-Making Methods in Railway Engineering: A Case Study of Train Control Information Systems (TCIS)

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    In order to improve its position in the transport market railway, as a complex system, it has to fulfill a number of objectives such as increased capacity and asset utilization, improved reliability and safety, higher customer service levels, better energy efficiency and fewer emissions, along with increased economic viability and profits. Some of these objectives call for the implementation of maximum values, while some of them require minimum values. Additionally, some can be expressed quantitatively, while some, for example, customer service, can be described qualitatively through a descriptive scale of points. The application of MCDM in railway engineering can play a significant role. Therefore, the major objective of this chapter is the review of the application of MCDM methods in railway engineering. As one of the means in achieving the objectives of railways and above all the utilization of capacity are Train Control Information Systems (TCIS). Based on that, the aim of this chapter is the evaluation of the efficiency of TCIS in the improvement of railway capacity utilization through defined technical-technological indicators. The non-radial Data Envelopment Analysis (DEA) model for the evaluation of TCIS efficiency in improvement of utilization of railway capacity using the selected indicators is proposed. The proposed non-radial DEA model for TCIS efficiency evaluation in using railway capacity could be applied to an overall network or for separate parts of railway lines

    Techno-economic analysis of solar stills using integrated fuzzy analytical hierarchy process and data envelopment analysis

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    Desalination using solar stills is an ancient economic method for water desalination. Over the years, research and development in the area of solar still has resulted in increased distillate yield by means of integration of PCM (phase change material), photo-voltaic thermal (PVT), etc with the still. Nano-PCM is an upcoming technology which modifies the thermal performance of PCM. The aim of this research is to analyze the efficiency of 20 solar stills including nano-PCM based solar stills considering various input and output criteria using integrated fuzzy analytical hierarchy process (AHP) and data envelopment analysis (DEA). The efficiency derived here is relative with regard to the parameters and stills considered in this study. The result infers that, even though the productivity of stepped solar still with sun tracking system was high, but when techno-economic aspects were considered it is not among the top solar stills. The analysis indicated pyramid type solar still, single slope solar still with PVT, solar still with NPCM (paraffin + copper oxide), solar still with NPCM (paraffin + titanium dioxide) and solar still with PCM (paraffin) occupies the top five positions with relative efficiency of 100, 100, 88.47, 88.46 and 76.93% respectively

    Application of Optimization in Production, Logistics, Inventory, Supply Chain Management and Block Chain

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    The evolution of industrial development since the 18th century is now experiencing the fourth industrial revolution. The effect of the development has propagated into almost every sector of the industry. From inventory to the circular economy, the effectiveness of technology has been fruitful for industry. The recent trends in research, with new ideas and methodologies, are included in this book. Several new ideas and business strategies are developed in the area of the supply chain management, logistics, optimization, and forecasting for the improvement of the economy of the society and the environment. The proposed technologies and ideas are either novel or help modify several other new ideas. Different real life problems with different dimensions are discussed in the book so that readers may connect with the recent issues in society and industry. The collection of the articles provides a glimpse into the new research trends in technology, business, and the environment

    A novel hybrid fuzzy DEA-Fuzzy MADM method for airlines safety evaluation

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    Safety is a critical element in the air transport industry. Although fatal air accidents are rare compared to other transport industries, the rapid growth in air travel demands has resulted in a growing aviation risk exposure and new challenges in the aviation sector. Although the issue of airline safety is of serious public concern, notably few studies have investigated the safety efficiency of airlines. This paper aims to propose a novel hybrid method using fuzzy data envelopment analysis (DEA) and fuzzy multi-attribute decision making (F-MADM) for ranking the airlines’ safety. In this study, fuzzy DEA is utilized to calculate criteria weights, in contrast to the conventional approach of using DEA for measuring the efficiency of alternatives. A ranking of each airline (DMU) on the basis of obtained weights is then assessed using MADM methods. Six MADM methods including Fuzzy SAW, Fuzzy TOPSIS, Fuzzy VIKOR, ARAS-F, COPRAS-F and Fuzzy MULTIMOORA are implemented to rank the alternatives, and finally, the results are compounded with the utility interval technique. This new hybrid method can efficiently overcome the pitfalls of traditional hybrid DEA-MADM models. The method proposed in this study is used to evaluate the safety levels of seven Iranian airlines and to select the safest one. © 2018 Elsevier Lt

    Assessing the efficiency of airports considering health and safety issues: A pilot study for Turkey

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    Purpose: Airport management is influenced by several related critical decisions on financial and technical operations. Optimum utilization of resources, including assets and personnel, is critical to achieve better service quality for the passengers and an efficient airport. Due to its importance, this paper aims to assess the performance of airports based on security, safety, and possible work-related health problems by considering the uncertain and unclear number of passengers and their baggage. Design/methodology: The efficiency of 30 airports in Turkey is evaluated with a basic Data Envelopment Analysis (DEA) model with two inputs and five outputs. Then, the model is redefined with an undesired output. High, medium, and low seasons are defined in the second DEA model to estimate the number of passenger baggage. The third model utilizes the principles of Fuzzy DEA (F-DEA) that aims to handle the uncertainty for the undesired output data. Findings: The results of three models confirm that the number and weight of baggage and consequently health and safety issues in airports should not be overlooked when optimizing airport efficiency. Utilizing the fuzzy theory has the potential to help managers to improve the operational efficiency of airports when dealing with an uncertain number of passengers and estimating the workload of baggage handlers. Research limitations/implications: No permission was given to make interviews with the ground handling personnel and gather real-life data to analyze task durations and workers’ body movements. Practical implications: Inputs, outputs, and undesired output defined in this study can be used to assess the airports in any other country. Social implications: The importance of health and safety issues for passengers, airport personnel, baggage handlers, and the residents who live close to the airports is considered. Originality/value: This study contributes to the airport performance assessment literature by considering the uncertain and dynamic data related to health and safety issues. This pioneering study, up-to-best knowledge, is the first to assess the airports in Turkey by DEA with the defined undesired output (baggage handler workload) and also utilizing the fuzzy model for the uncertain data.Peer Reviewe

    Appropriate building repair and maintenance strategies using multicriteria decision-making analysis – a Delphi study

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    As an influential and significant factor in improving the service of building components and elements, maintenance plays an essential role in maintaining reliability, availability, and quality, as well as increasing efficiency and security. Therefore, how to define this maintenance system and determine the appropriate criteria and strategies for that play an important role in the cost and longevity of the buildings after construction and during their operation. The purpose of the article is to determine the effective criteria for evaluating buildings based on maintenance and repair (R&M) and finally determining the appropriate strategy for the maintenance of residential buildings, using multicriteria decision-making methods. These criteria were first identified by reviewing the literature and using the Delphi method to obtain the opinions of maintenance experts. The criteria were then prioritized, based on the SWARA method, and the results were compared and evaluated. Based on comparison, safety, health, environment, and proper utilisation were rated the top four criteria to consider for building R&M. Finally, using the VIKOR2 method, it was found that the breakdown maintenance (BM) and corrective maintenance (CM) strategies are the best strategies to use for the R&M of residential buildings

    Sustainability Assessment Framework for Buildings: A User Perspective

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    According to the Intergovernmental Panel on Climate Change, the building sector accounts for 32% of global energy consumption, 19% of energy-related CO₂ emissions and 51% of global electricity consumption. Moreover, numerous studies have highlighted that the operational phase is considered to be the most crucial stage in a building’s lifecycle, accounting for 70-90% of a building’s overall impact on the environment. However, over the past few decades, practitioners and researchers have worked together to develop frameworks that enhance and evaluate the sustainability of buildings using different measures and technologies. The majority of these frameworks address sustainability from economic and organizational perspectives. However, considerably less work has focused on assessing and enhancing the sustainability of buildings from the user’s perspective. The present research aims to develop a new and comprehensive framework that assists users in assessing and updating sustainability from a user’s perspective. The developed methodology consists of four levels: 1) Identify and study the factors that contribute to building sustainability from users’/occupants’ perspectives; 2) Develop a user-based framework to assess and enhance the sustainability of existing buildings; 3) Develop a framework to upgrade conventional buildings into sustainable ones, based on the user’s perspective; and 4) Develop a User-based Sustainability Assessment and Upgrading Tool (USAUT) to assess and enhance the user’s perspective in existing buildings. The research utilized two modeling techniques: Fuzzy Expert Systems and a fuzzy ANP model to determine the overall user perspective scale (OSS) and the weight of each factor and sub-factor. In addition, the Pugh Matrix is utilized and integrated with Genetic Algorithm GA optimization to determine several optimal or near optimal alternatives. The user’s perspective assessment model was implemented with an actual education building case study in Montreal, Canada (the E.V. building at Concordia University). Collecting data such as the dissatisfaction level based on the users’ perspective, the weight of each factor, sub-factor and on user’s opinions was a crucial step. This was accomplished by utilizing questionnaires and interviews with (100 facility managers (FM) and building experts and 40 users) at Concordia University and its users, while observing the guidelines of Concordia University’s ethics protocols. Based on the information in the FM’s and building expert’s questionnaires, the OSS differs based on a 5-point Likert scale as trapezoidal fuzzy numbers (TFN) according to each type of building (Industrial, Commercial, Education, and Residential). Within the Education buildings that are represented with the E.V. building as a case study, the research revealed the difference between the user’s perspective weights for the main user’s perspective factors (Thermal comfort and air quality, Aesthetics, Design and flexibility, and Lighting and acoustics). For example, the highest weights among the main four factors were Thermal comfort with 40% and Aesthetics with 22%. In addition, the E.V. building’s users’ s opinions revealed that the E.V. building rates a score of 5.7 as a building sustainability BS, which means that the E.V. building was located in the U zone when the researchers compared it with the OSS, and thus required an immediate user’s perspective upgrade. The factors that do not meet the user’s perspective based on OSS are thermal comfort and lightening and acoustics. To propose options to upgrade these aspects, the users’ perspective upgrade model used three different scenarios (Optimistic, Pessimistic and Average). The model illustrated that the optimal scenario is the optimistic scenario with $180000 and 15000 Hr and which improved the BS from 5.7 to 7 out of 10. The main contribution of the present research can be presented in two main points: 1) it determines the current users’ perspective of four types of buildings and highlights the weak areas that require more attention from the users’ perspective, and 2) it proposes various rehabilitation alternatives that upgrade the users’ perspective in sustainable buildings as a step towards establishing a comprehensive global sustainability assessment framework for buildings from the user’s perspective

    EA-BJ-03

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    A systematic review of application of multi-criteria decision analysis for aging-dam management

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    [EN] Decisions for aging-dam management requires a transparent process to prevent the dam failure, thus to avoid severe consequences in socio-economic and environmental terms. Multiple criteria analysis arose to model complex problems like this. This paper reviews specific problems, applications and Multi-Criteria Decision Making techniques for dam management. Multi-Attribute Decision Making techniques had a major presence under the single approach, specially the Analytic Hierarchy Process, and its combination with Technique for Order of Preference by Similarity to Ideal Solution was prominent under the hybrid approach; while a high variety of complementary techniques was identified. A growing hybridization and fuzzification are the two most relevant trends observed. The integration of stakeholders within the decision making process and the inclusion of trade-offs and interactions between components within the evaluation model must receive a deeper exploration. Despite the progressive consolidation of Multi-Criteria Decision Making in dam management, further research is required to differentiate between rational and intuitive decision processes. Additionally, the need to address benefits, opportunities, costs and risks related to repair, upgrading or removal measures in aging dams suggests the Analytic Network Process, not yet explored under this approach, as an interesting path worth investigating.This research was funded by the Spanish Ministry of Economy and Competitiveness along with FEDER funding (Projects BIA201456574-R and ECO2015-66673-R).Zamarrón-Mieza, I.; Yepes, V.; Moreno-Jiménez, JM. (2017). A systematic review of application of multi-criteria decision analysis for aging-dam management. Journal of Cleaner Production. 147:217-230. https://doi.org/10.1016/j.jclepro.2017.01.092S21723014
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