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Article Citation - WoS: 16Citation - Scopus: 18A Comprehensive Comparison and Accuracy of Different Methods To Obtain Mean Radiant Temperature in Indoor Environment(Elsevier, 2022) Ozbey, Mehmet Furkan; Turhan, CihanThermal comfort is defined as "the state of mind which expresses satisfaction with the thermal environment" by the American Society of Heating, Refrigerating and Air Conditioning Engineers in the standard of the ASHRAE55. Thermal comfort is affected by six main parameters which are split into two categories; personal (basic clothing insulation value and metabolic rate) and environmental (air temperature, relative humidity, air velocity, and mean radiant temperature) parameters. The mean radiant temperature is a problematic parameter in thermal comfort studies due to its complexity. The mean radiant temperature approaches are based on different techniques such as calculation methods, measurement methods, and assumptions. Although the assumptions are utilized by researchers to abstain complexity, their accuracies are uncertain. To this aim, this study purposes to find the accuracies of calculation and assumption methods by comparing with reference measurement method. An office building in a temperate climate zone is selected as a case study. Two calculation methods and eight assumptions on obtaining mean radiant temperature are compared via in-situ measurements. The results revealed that using assumptions or calculation methods to obtain the mean radiant temperature caused a significant error compared to the reference method and researchers should consider accuracies of these methods before utilizing them in their applications.Conference Object Citation - WoS: 1Citation - Scopus: 2Hardware-In Assessment of a Fault Tolerant Fuzzy Control Scheme for an Offshore Wind Farm Simulator(Elsevier, 2022) Simani, Silvio; Farsoni, Saverio; Turhan, CihanTo enhance both the safety and the efficiency of offshore wind park systems, faults must be accommodated in their earlier occurrence, in order to avoid costly unplanned maintenance. Therefore, this paper aims at implementing a fault tolerant control strategy by means of a data-driven approach relying on fuzzy logic. In particular, fuzzy modelling is considered here as it enables to approximate unknown nonlinear relations, while managing uncertain measurements and disturbance. On the other hand, the model of the fuzzy controller is directly estimated from the input-output signals acquired from the wind farm system, with fault tolerant capabilities. In general, the use of purely nonlinear relations and analytic methods would require more complex design tools. The design is therefore enhanced by the use of fuzzy model prototypes obtained via a data-driven approach, thus representing the key point if real-time solutions have to implement the proposed fault tolerant control strategy. Finally, a high-fidelity simulator relying on a hardware-in-the-loop tool is exploited to verify and validate the reliability and robustness characteristics of the developed methodology also for on-line and more realistic implementations. Copyright (C) 2022 The Authors.Article Citation - WoS: 20Citation - Scopus: 23A Novel Comfort Temperature Determination Model Based on Psychology of the Participants for Educational Buildings in a Temperate Climate Zone(Elsevier, 2023) Ozbey, Mehmet Furkan; Turhan, CihanMaintaining thermal comfort in the educational buildings is vital due to the impacts on learning effectiveness of students. Therefore, development of a proper comfort temperature in educational buildings is a must. In naturally ventilated and mixed-mode buildings, the adaptive thermal comfort model, which considers additively psychological, and behavioural factors to the Fanger's PMV/PPD model, is commonly applied based on regression analyses. However, the psychological adjustments based on current mood state are very limited in these adaptive thermal comfort models. Therefore, this study focuses on the psychological adjustments in terms of Profile of Mood States in order to predict comfort temperature of students in a case building. The experiments are conducted in a university on a temperate climate zone for a long period-data including both heating and cooling seasons. In this study, the comfort temperatures for each student are determined via Griffith method for the case building. Moreover, the current mood states of students are assessed utilizing the Profile of Mood States survey, which are collected via a developed mobile application. As a conclusion, the relation between the current mood state of the students and comfort temperature are statistically investigated. The results show that a Griffith constant are found as 0.332/K and mean annual comfort temperature is found as 21.32 degrees C in the case building. Additionally, a significant difference is found in the comfort temperatures among the students who have more, or fewer concerns than typically reported. The novelty of the study is to present a comfort temperature determination model which considers human psychology as a starter study in the literature.Article Citation - WoS: 48Citation - Scopus: 52A Comprehensive Evaluation of the Most Suitable Hvac System for an Industrial Building by Using a Hybrid Building Energy Simulation and Multi Criteria Decision Making Framework(Elsevier, 2021) Bac, Ugur; Alaloosi, Khalid Abdulwahab Mohamed Saed; Turhan, CihanGreat demand for energy and growing trend in the use of energy-efficient HVAC systems force researchers to focus on the importance of choosing the most appropriate HVAC system for industrial buildings during design process. Therefore, developing a model to select the most suitable HVAC system is vital for industrial buildings. To this aim, this study provides a comprehensive evaluation of different HVAC systems for an industrial building by using hybrid multi criteria decision making (MCDM) method. An industrial building in Ankara/Turkey is selected as a case building. Eleven HVAC systems are evaluated based on twenty seven criteria, which are determined as a result of extensive literature research, and are grouped under six categories including ergonomic, environmental, reliability, technical, and economical aspects. A hybrid application of building energy simulation (BES) integrated modified Stepwise Weight Assessment Ratio Analysis (SWARA) and Weighted Additive Sum Product Assessment (WASPAS) framework is developed for supporting the decision making process. The novelty of the study is integrating the objective results of a well-calibrated dynamic BES tool with subjective criteria which are collected from expert opinions by applying questionnaires with face-to-face interview method. The results of MCDM framework and sensitivity analysis showed that the water-source heat pump is the best and suitable alternative for the industrial building. The outcome of this study would benefit the HVAC engineers and specialists in order to design the best HVAC systems in industrial buildings while providing an insight into different criteria. Moreover, key contribution to the literature is the usage of hybrid MCDM framework integrated with BES tool in the building sector.
