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Yayın A global optimal control methodology and its application to a mobile robot model(Elsevier B.V., 2016) Dinçmen, ErkinA global optimal control algorithm is developed and applied to an omni-directional mobile robot model. The aim is to search and find the most intense signal source among other signal sources in the operation region of the robot. In other words, the control problem is to find the global extremum point when there are local extremas. The locations of the signal sources are unknown and it is assumed that the signal magnitudes are maximum at the sources and their magnitudes are decreasing away from the sources. The distribution characteristics of the signals are unknown, i.e. the gradients of the signal distribution functions are unknown. The control algorithm also doesn't need any position measurement of the robot itself. Only the signal magnitude should be measured via a sensor mounted on the robot. The simulation study shows the performance of the controller.Yayın Optimization of fertile land usage and agricultural production of Turkey(Işık Üniversitesi, 2017-01-18) Arslan, Şafak; Altunbay, Seyhun; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Endüstri Mühendisliği - Yöneylem Araştırması Yüksek Lisans ProgramıTurkey has a large amount of land which is suitable for agriculture. On the other hand, agricultural activities gradually decrease every year. Moreover, the fertile lands are not used effectively. As a result, production of agricultural goods does not satisfy the domestic demand. Thus, Turkey is obliged to import lots of agricultural goods in the recent decade.Turkey has to develop the agricultural potential and productivity and demand -supply stability as soon as possible. For this purpose, an optimization model has been developed to optimize the fertile land usage and agricultural production to satisfy the increasing agricultural demand of Turkey. Residential settlements on fertile lands are another problem about the agriculturalland usage of Turkey. The fertile lands are allowed for the construction of residential settlements and this causes the decrease of the fertile land area beside a lot of negative effects to the national economy and nature.This study aims to find solutions to these problems with the help of an optimization model. Specifically, which parts of land has to be farmed, which products has to be cultivated, how much has to be cultivated, how much area has to be used for the cultivation of a specific product. Additionally, the model will yield the effect of loss of fertile land due to residential settlements on fertile lands.Yayın Extremum seeking control of uncertain systems(Işık University Press, 2017) Dinçmen, ErkinExtremum seeking is used in control problems where the reference trajectory or reference set point of the system is not known but it is searched in real time in order to maximize or minimize a performance function representing the optimal behaviour of the system. In this paper, extremum seeking algorithm is applied to the systems with parametric uncertainties.Yayın Inventory management and pricing in existence of secondary markets(Işık Üniversitesi, 2019-08-01) Kaya, Burak Erkan; Hekimoğlu, Mustafa; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Endüstri Mühendisliği - Yöneylem Araştırması Yüksek Lisans ProgramıSecondary markets are easily accessible market-places for every participant of a product market, where usually lower prices and shorter lead times than the Original Equipment Manufacturer (OEM) are o?ered. Especially when price is dynamic, determining procurement amount is very important for the OEM who wants to maximize pro?t in existence of secondary markets. The goal of this study is to put an approach forward for maximizing pro?t of the OEM by taking into consideration price and procurement amounts from di?erent suppliers. We consider a trade environment in which OEM is not only a seller on secondary markets but also a buyer. We propose 2 single period additive non-linear maximization models by taking into consideration access priority of the OEM or Price Sensitive Customers (PSC) to secondary markets. We examine proposed models analytically and analyze one of them with Karush-Kuhn-Tucker (KKT) conditions. Due to analytical impracticalities faced in numerical experiments a brutal force search algorithm is applied under some assumptions. Our research provides some managerial insights about inventory management and pricing by considering some parameters as constant. We show e?ects of procurement from di?erent supply sources under our assumptions.Yayın An automatic calibration procedure of driving behaviour parameters in the presence of high bus volume(Faculty of Transport and Traffic Engineering, 2019-11) Dadashzadeh, Nima; Ergün, Murat; Kesten, Ali Sercan; Zura, MarijanMost of the microscopic traffic simulation programs used today incorporate car-following and lane-change models to simulate driving behaviour across a given area. The main goal of this study has been to develop an automatic calibration process for the parameters of driving behaviour models using metaheuristic algorithms. Genetic Algorithm (GA), Particle Swarm Optimization (PSO), and a combination of GA and PSO (i.e. hybrid GAPSO and hybrid PSOGA) were used during the optimization stage. In order to verify our proposed methodology, a suitable study area with high bus volume on-ramp from the 0-1 Highway in Istanbul has been modelled in VISSIM. Traffic data have been gathered through detectors. The calibration procedure has been coded using MATLAB and implemented via the VISSIM-MATLAB COM interface. Using the proposed methodology, the results of the calibrated model showed that hybrid GAPSO and hybrid PSOGA techniques outperformed the GA-only and PSO-only techniques during the calibration process. Thus, both are recommended for use in the calibration of microsimulation traffic models, rather than GA-only and PSO-only techniques.Yayın Battle Royale Optimizer for solving binary optimization problems(Elsevier B.V., 2022-05) Akan, Taymaz; Agahian, Saeid; Dehkharghani, RahimBattle Royale Optimizer (BRO) is a recently proposed metaheuristic optimization algorithm used only in continuous problem spaces. The BinBRO is a binary version of BRO. The BinBRO algorithm employs a differential expression, which utilizes a dissimilarity measure between binary vectors instead of a vector subtraction operator, used in the original BRO algorithm to find the nearest neighbor. To evaluate BinBRO, we applied it to two popular benchmark datasets: the uncapacitated facility location problem (UFLP) and the maximum-cut (Max-Cut) graph problems from OR-Library. An open-source MATLAB implementation of BinBRO is available on CodeOcean and GitHub websites.Yayın Effectiveness of standalone simulation-based optimization software in optimizing the life cycle cost of residential buildings(Dynamic Academy Yazılım İnşaat San. Tic. Ltd. Şti., 2021-12) Yiğit, Sadık; Ozorhon, BelizDesigners aim to build nearly zero energy buildings and positive energy buildings to comply with regulations. However, due to many variables affecting the energy performance of buildings, energy-efficient building design is a challenging task. Among the proposed methods, simulation-based systems are promising. The proposed simulation-based systems are not suitable for the construction sector because of the long optimization periods. The primary goal of this study is to emphasize the necessity of standalone software packages in solving usability problems and to provide a tool for designers and architects to incorporate into their daily works. To demonstrate the advantages of standalone software a test study was conducted to find a cost-optimal configuration for a typical residential building. In addition, the obtained cost-optimal design was compared to the energy-optimal design obtained in previous studies and it was seen that the outcomes are in parallel with the results of previous studies. It was observed that the optimum insulation thickness obtained from the case study is significantly higher than the limiting values in the national regulation. The results of the parametric analysis demonstrated that wall type, window area, and window type have the highest influence on thermal performance. The results of the study have confirmed that stand-alone software performs optimizations faster overcomes the shortcomings of simulation-based optimization systems comprising integrated multiple software packages.Yayın Multiresponse optimisation of powder metals via probabilistic loss functions(Inderscience Enterprises Ltd, 2013) Aksezer, Sezgin Çağlar; Benneyan, James C.Quadratic loss functions have been used extensively within the context of quality engineering and experimental design for process and product optimisation and robust design. In general, this approach determines optimal parameter settings based on minimising the sum of individual or mean loss of the associated response(s) of interest in a defined response surface. While the method is neat and handy, it totally neglects the effect of deviations on the desirable value of loss function. This paper utilises variance and probability distribution of loss functions for developing an in depth optimisation scheme that balances mean and variance of loss in a Pareto optimal manner. Since losses are usually defined in financial terms, this model then further improved to handle the user determined risk levels so that financial losses are being restricted within a certain region of interest. Application of the model is illustrated on a multiresponse optimisation problem from powder metallurgy industry.Yayın The comparison of functional connectivity in Parkinson’s Disease patients with and without Parkin gene mutations(Turkish Neuropsychiatric Society, 2025-06-19) Çebi, Merve; Ay, Ulaş; Kıçik, Ani; Erdoğdu, Emel; Tepgeç, Fatih; Uyguner, Zehra Oya; Tüfekçioğlu, Zeynep; Samancı, Bedia; Bilgiç, Başar; Emre, Murat; Demiralp, Tamer; Hanağası, Haşmet AyhanIntroduction: Mapping the functional connectivity of brain regions became appealing in recent research in neurology. Accordingly, a growing body of evidence shows resting-state functional connectivity (rsFC) changes in neurodegenerative disorders including Parkinson’s Disease (PD). As characterised by extensive and progressive dopaminergic loss in the substantia nigra, PD emerges with serious motor and non-motor dysfunctions. In the literature, the minority of PD cases have been associated with certain genetic mutations. The aim of this study was to investigate the rsFC in a group of PD patients having Parkin gene mutation. Method: Twelve PD patients with Parkin mutation (PP-PD), 12 PD patients without Parkin mutation (PN-PD) and 12 healthy controls (HC) were included in the study. All participants underwent a resting-state functional magnetic resonance imaging as well as a neuropsychological assessment and clinical examination. Results: Results indicated that PP-PD had longer disease duration, a higher rate of dyskinesia and lower scores on complex visual perception tests. The resting state networks showed that all PD (consisting of PP-PD and PN-PD) and PP-PD groups had increased functional connectivity in the frontoparietal network as compared to the HC. In addition, the PP-PD group displayed decreased functional connectivity in the dorsal attention network compared to the PN-PD. Conclusion: In conclusion, our data suggests that PD with Parkin gene mutation might be emerging with distinct resting state functional connectivity changes in the brain.
