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  • Conference Object
    Citation - WoS: 5
    Citation - Scopus: 3
    Evaluation of Efficiencies of Diffuse Allochthonous and Autochthonous Nutrient Input Control in Restoration of a Highly Eutrophic Lake
    (I W A Publishing, 2002) Muhammetoglu, A; Muhammetoglu, H; Soyupak, S
    Mogan Lake is an important recreational area for Metropolitan Ankara-Turkey. It is a shallow eutrophic lake with a dense growth of macrophytes. The main contributors of nutrients and other pollutants to the lake are the creeks carrying the runoff water from the watershed and upland farming land, in addition to the domestic and industrial wastewater discharges from a nearby town and industries. Hydrodynamic and water quality modeling techniques were used to determine the optimum management schemes for the lake restoration and diffuse pollution control. Management scenarios were devised and tested to control allochthonous and autochthonous nutrient inputs to the lake. Phosphorus and nitrogen load reductions were the main test elements for the control of allochthonous nutrient inputs. The scenario analysis revealed that reduction of phosphorus and nitrogen loads from diffused sources will have a marginal effect on controlling eutrophication if macrophyte growth is left uncontrolled. Scenarios employing macrophyte harvesting and sediment dredging have been evaluated for autochthonous nutrient input control. Sediment dredging alone has been shown to yield the most favorable conditions for water quality improvement in Mogan Lake. Further, control of diffuse pollution was an essential final step to achieve an acceptable long-term sustainable water quality improvement in the lake.
  • Conference Object
    Citation - Scopus: 6
    The Use of Semi-Public Spaces as Urban Space and Evaluation in Terms of Urban Space Quality
    (Springer Nature, 2022) Orhan,M.
    The rapid physical change and increase in density of today’s cities lead to changes in urban space usage and habits in urban life. This change negatively affects the description and use of public spaces as socialisation spaces, which are one of the most significant urban components. As a result, city dwellers satisfy their need for public spaces with the use of different urban spaces. Urban life shifts from urban public spaces to semi-public spaces. Semi-public spaces are qualified and accessible spaces that ensure transition between private spaces (buildings) and public spaces. These spaces gain different attributes according to the characteristics (commerce, housing, tourism, etc.) of the urban spaces they coexist within and to the functions and designs of the structures surrounding them. These attributes determine their configuration as integrated or dissociated with the city and thus specify their relationship with the city. This relationship changes ‘city–space–structure–human’ interaction, and this change affects urban quality with the spatial quality of semi-public spaces. The aim of this study is to present how and related to which characteristics the use of semi-public spaces as urban spaces has changed, to detect the effects of this change on the urban environment and to establish the role of semi-public spaces in terms of urban quality. In conclusion, semi-public spaces with different characteristics located in different urban spaces will be examined as regards physical, schematic, functional characteristics and use within the scope of this study. In accordance with the data obtained by comparative analysis method, approaches to facilitate their use as urban spaces and to ensure their integration with the city will be introduced. Accordingly, criteria that semi-public spaces should possess in order to increase and sustain urban space quality will be determined. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
  • Conference Object
    Complexity Engineering, Evolution and Optimality of Structures
    (Morgan Kaufmann Pub inc, 1999) Kundu, S
    Complexity Engineering deals with harnessing the power of Cellular Automata (CA) like simple models to solve real life difficult and complex engineering problems, dealing with systems that have very simple components that collectively exhibit complex behaviors. The state transition rules are generally fixed in a CA, but evolution of the rules, is considered here. To evolve the local rules, we use the Genetic Algorithm (GA) model. The example application described here will serve to demonstrate that the GAs can discover CA rules that give rise to emergent computational strategies by self-organization and exhibit globally coordinated tasks for optimization, with simple local interactions only.
  • Conference Object
    Citation - Scopus: 4
    Bicriteria Scheduling Problem on the Two-Machine Flowshop Using Simulated Annealing
    (Springer Verlag, 2010) Mesgarpour,M.; Kirkavak,N.; Ozaktas,H.
    Real life scheduling problems require the decision maker to consider a number of criteria before arriving at any decision. The trade-offs involved in considering several different criteria provide useful insights for the decision maker. Surprisingly, research in the field of multi-objective scheduling has been quite limited when compared to research in single criterion scheduling. The subject of this paper is the bicriteria scheduling problem in a two-machine flowshop. The objective is to find a job sequence that minimizes sum of weighted total flowtime and total tardiness. Based on the problem characteristics, a Simulated Annealing algorithm is developed. The proposed metaheuristic is compared with the branch and bound enumeration algorithm of the integer programming model as well as a modified version of the well-known NEH algorithm. During these evaluations, the experimental design approach and careful statistical analysis have been used to validate the effectiveness of the simulated annealing approach. © 2010 Springer-Verlag Berlin Heidelberg.
  • Conference Object
    Citation - WoS: 4
    Citation - Scopus: 6
    A Reinforcement Learning Algorithm for Data Collection in Uav-Aided Iot Networks With Uncertain Time Windows
    (Ieee, 2021) Cicek, Cihan Tugrul
    Unmanned aerial vehicles (UAVs) have been considered as an efficient solution to collect data from ground sensor nodes in Internet-of-Things (IoT) networks due to their several advantages such as flexibility, quick deployment and maneuverability. Studies on this subject have been mainly focused on problems where limited UAV battery is introduced as a tight constraint that shortens the mission time in the models, which significantly undervalues the UAV potential. Moreover, the sensors in the network are typically assumed to have deterministic working times during which the data is uploaded. In this study, we revisit the UAV trajectory planning problem with a different approach and revise the battery constraint by allowing UAVs to swap their batteries at fixed stations and continue their data collection task, hence, the planning horizon can be extended. In particular, we develop a discrete time Markov process (DTMP) in which the UAV trajectory and battery swapping times are jointly determined to minimize the total data loss in the network, where the sensors have uncertain time windows for uploading. Due to the so-called curse-of-dimensionality, we propose a reinforcement learning (RL) algorithm in which the UAV is trained as an agent to explore the network. The computational study shows that our proposed algorithm outperforms two benchmark approaches and achieves significant reduction in data loss.
  • Conference Object
    Citation - Scopus: 4
    Convolution Neural Network (cnn) Based Automatic Sorting of Cherries
    (Institute of Electrical and Electronics Engineers Inc., 2021) Park,H.; Khan,M.U.
    Cherries are spring fruits enriched with nutrients, and are easily available in food markets around the world. Due to their excess demand, many enterprises solely focused on their processing. Cherries are especially susceptible to pathological-, physiological-diseases and structural degradation due to their soft outer skin. The post-harvest life of the fruit is limited by various characteristics. The agricultural industry has also been at the forefront to get benefits from the advanced machine learning tools. This study presents an image processing-based system for sorting cherries using the convolutional neural network (CNN). For this study, Prunus avium L cherries of export quality, available in Turkey, tagged as ‘0900 Ziraat’, are used. Surprisingly, there exists no dataset for these cherries; hence, we developed our dataset. Through the proposed approach based upon U-Net, the binary classification accuracy of 99% is achieved. Clear identification is demonstrated by the test results of varying mixture ratios of good and bad cherries. It can therefore be said that for cherry sorting and grading, U-Net can be applied as a reliable and promising machine learning tool. ©2021 IEEE
  • Conference Object
    Analysis of Force-Indentation Measurements on Anisotropic Metals
    (Edizioni libreria progetto, 2005) Koray,E.; Topcu,N.; Tekkaya,A.E.
    Indentation tests are widely used with simultaneous measurements of indentation depth and force especially for determining material properties. In this study, findings on parameters affecting the force-displacement curves obtained from indentations on anisotropic metals using special not self-similar indenters will be presented. Parameters such as specimen dimensions, friction, surface roughness, specimen clamping and indentation spacing have been investigated by finite element analysis and by experiments. Optimum values of these parameters to achieve higher repeatability and accuracy are determined.
  • Conference Object
    Citation - WoS: 6
    Personality and Individual Differences: Literature in Psychology-Psychology in Literature
    (Elsevier Science Bv, 2015) Aras, Goksen
    Literature, which intertwines within such fields as history, philosophy, sociology, psychology and so on, is a discipline wherein language is used as a medium of expression so as to interpret man, existence and culture. The objective of this paper is to discuss literature in terms of its interdisciplinary structure, psychology, in particular, considering man and existence, personality and individual differences which have always been studied by writers, philosophers, artists, psychologists and psychiatrists. Several complex notions, unfathomable personalities and ambiguous motives have been associated with characters in literary genres: For example the term Bovarism is explained by means of Flaubert's Madame Bovary. Similar examples in literary works could be multiplied. Man and existence have been fundamental themes in literature, which has existed even before psychology. Works of literature and art enable individuals to be aware of their personalities and individual differences and to question life and existence, the main data in the field of psychology as well. It is overtly seen that there is a very strong correlation between literature and psychology since both of them deal with human beings and their reactions, miseries, desires, and their individual and social concerns by means of different concepts, methods, and approaches. (C) 2015 The Authors. Published by Elsevier Ltd.
  • Conference Object
    Citation - Scopus: 3
    A hybrid intuitionistic MCDM model for supplier selection
    (2013) Rouyendegh,B.D.
    This paper gives an overview of the Analytic Hierarchy Process (AHP) and Intuitionistic Fuzzy TOPSIS (IFT) methods. This study deals an evaluation methodology based on the AHP-IFT where the uncertainty is handeled with linguistic values. First, the supplier selection problem is formulated by AHP is used to determine weights of the criteria. In the second stage, IFT used to obtain full ranking among alternatives based on opinion of the Decision Makers (DMs). The present model provides an accurate and easy classification in supplier attributes by that have been prioritized in the hybrid model. A numerical example is given to clarify the main developed result in this paper.
  • Conference Object
    Design and Optimization of a Notional Scramjet by Means of Stream Thrust Analysis and Design of Experiments
    (American Institute of Aeronautics and Astronautics Inc., 2014) Akpolat,M.T.; Toker,K.A.; Genç,M.S.
    Within the scope of this study, a 0-dimensional code is developed by using Stream Thrust Analysis in order to evaluate scramjet cycle performance with respect to selected performance parameters (specific impulse, overall efficiency) and combustion chamber exit temperature. By using the results of this code an analysis employing "Design of Experiments" (DoE) is performed to determine the most effective input parameters and/or interactions on the scramjet performance. The results showed that most effective input parameter for all of the selected parameters is fuel/air ratio. Selected parameters are evaluated first individually then simultaneously. The purpose of evaluating the performance parameters simultaneously is to determine the input parameter set which gives the highest values of specific impulse and overall efficiency while giving the lowest value of combustion chamber exit temperature. As a result the input parameter sets for different cases are determined.