@article {1587, title = {A reference set based many-objective co-evolutionary algorithm with an application to the knapsack problem}, journal = {European Journal of Operational Research}, volume = {300}, year = {2022}, pages = {405{\textendash}417}, doi = {10.1016/j.ejor.2021.10.033}, url = {https://doi.org/10.1016/j.ejor.2021.10.033}, author = {H. Mert Sahinkoc and {\"U}mit Bilge} } @article {1542, title = {An Exact Cutting Plane Algorithm to Solve the Selective Graph Coloring Problem in Perfect Graphs}, journal = {European Journal of Operational Research}, volume = {291(1)}, year = {2021}, pages = {67{\textendash}83}, doi = {https://doi.org/10.1016/j.ejor.2020.09.017}, author = {Oylum {\c S}eker and Ekim, Tinaz and Z C Ta{\c s}k{\i}n} } @article {1535, title = {Learning prototypes for multiple instance learning.}, journal = {Turkish Journal of Electrical Engineering \& Computer Sciences}, volume = {29}, year = {2021}, author = {{\"O}zg{\"u}r Emre Sivrikaya and Mert Y{\"u}kselg{\"o}n{\"u}l and Mustafa Gokce Baydogan} } @article {1428, title = {On the Construction of Regular QC-LDPC Codes With Low Error Floor}, journal = {IEEE Communications Letters}, volume = {24}, year = {2020}, pages = {25-28}, doi = {10.1109/LCOMM.2019.2953058}, author = {Sar{\i}duman, Abdullah and Pusane, Ali E. and Z C Ta{\c s}k{\i}n} } @article {1441, title = {Exact solution algorithms for the maximum flow problem with additional conflict constraints}, journal = {European Journal of Operational Research}, volume = {287}, year = {2020}, pages = {410-437}, abstract = {

We consider a variant of the maximum flow problem on a given directed graph where some arc pairs are incompatible or conflicting; in other words, they are not allowed to carry positive flow simultaneously. This problem, called the maximum flow problem with conflicts, is known to be strongly NP-hard. In this paper, we present mixed-integer linear programming formulations for the problem and develop exact solution methods based on Benders decomposition, branch-and-bound, and Russian Doll Search over the conflict graph which represents the conflict relations. The effectiveness of the proposed algorithms is tested on a large number of randomly generated instances. The results reveal that their performances are superior to solving the mixed-integer linear programming formulations with a commercial software.

}, keywords = {Benders decomposition, Branch-and-bound, Combinatorial optimization, Conflict, Maximum flow, Russian doll search}, issn = {0377-2217}, doi = {https://doi.org/10.1016/j.ejor.2020.04.001}, url = {https://www.sciencedirect.com/science/article/pii/S0377221720303192}, author = {Zeynep {\c S}uvak and I. Kuban Altinel and Necati Aras} } @article {1449, title = {Modeling the pharmacodynamics of nandrolone doping drug and implications for anti-doping testing}, journal = {System Dynamics Review}, volume = {36}, year = {2020}, pages = {467-496}, abstract = {

Abstract We model the pathways of nandrolone in the body, an anabolic steroid widely used as a performance enhancing drug (PED). The model generates the dynamics of nandrolone and its metabolites. PED tests check for the presence of a primary metabolite of nandrolone, 19-NA in urine. To cheat in these tests, PED users typically use inhibitors that reduce the urinary concentration of 19-NA. One such inhibitor is finasteride. Finasteride{\textquoteright}s main effect in the body is the inhibition of reductase enzymes that turn nandrolone into its metabolite 19-NA. To capture this effect, we include structures for finasteride and reductase enzymes in the model. The model is tested by fundamental structure validity tests. We also show that the model behavior is consistent with experimental data in the literature. We finally investigate the potential ways by which the drug users may cheat in PED tests and make suggestions for improved testing as counter-measures. {\textcopyright} 2021 System Dynamics Society

}, doi = {https://doi.org/10.1002/sdr.1672}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/sdr.1672}, author = {Sahin, {\"O}zge and Feyyaz {\c S}ent{\"u}rk and Yaman Barlas and Yasarcan, Hakan} } @article {1473, title = {Profitable Decarbonization through E-Mobility}, journal = {Energies}, volume = {13}, year = {2020}, abstract = {

This paper focuses on the interdependent relationship of power generation, transportation and CO2 emissions to evaluate the impact of electric vehicle deployment on power generation and CO2 emissions. The value of this evaluation is in the employment of a large-scale, bottom-up, national energy modeling system that encompasses the complex relationships of producing, transforming, transmitting and supplying energy to meet the useful demand characteristics with great technological detail. One of such models employed in this analysis is the BUEMS model. The BUEMS model provides evidence of win-win policy options that lead to profitable decarbonization using Turkey{\textquoteright}s data in BUEMS. Specifically, the result shows that a ban on diesel fueled vehicles reduces lifetime emissions as well as lifetime costs. Furthermore, model results highlight the cost-effective emission reduction potential of e-buses in urban transportation. More insights from the results indicate that the marginal cost of emission reduction through e-bus transportation is much lower than that through other policy measures such as carbon taxation in transport. This paper highlights the crucial role the electricity sector plays in the sustainability of e-mobility and the value of related policy prescriptions.

}, issn = {1996-1073}, doi = {10.3390/en13164042}, url = {https://www.mdpi.com/1996-1073/13/16/4042}, author = {G{\"u}rkan Kumbaro{\u g}lu and Canaz, Cansu and Deason, Jonathan and Shittu, Ekundayo} } @article {1448, title = {The r-interdiction selective multi-depot vehicle routing problem}, journal = {International Transactions in Operational Research}, volume = {27}, year = {2020}, pages = {835-866}, abstract = {

Abstract The protection of critical facilities has been attracting increasing attention in the past two decades. Critical facilities involve physical assets such as bridges, railways, power plants, hospitals, and transportation hubs among others. In this study we introduce a bilevel optimization problem for the determination of the most critical depots in a vehicle routing context. The problem is modeled as an attacker{\textendash}defender game (Stackelberg game) from the perspective of an adversary agent (the attacker) who aims to inflict maximum disruption on a routing network. We refer to this problem as the r-interdiction selective multi-depot vehicle routing problem (RI-SMDVRP). The attacker is the decision maker in the upper level problem (ULP) who chooses r depots to interdict with certainty. The defender is the decision maker in the lower level problem (LLP) who optimizes the vehicle routes in the wake of the attack. The defender has to satisfy all customer demand either using the remaining depots or through outsourcing to a third party logistics service provider. The ULP is solved through exhaustive enumeration, which is viable when the cardinality of interdictions does not exceed five among nine depots. For the LLP we implement a tabu search heuristic adapted to the selective multi-depot VRP. Our results are obtained on a set of RI-SMDVRP instances synthetically constructed from standard MDVRP test instances.

}, keywords = {bilevel programming, interdiction, multi-depot vehicle routing problem, outsourcing, tabu search}, doi = {https://doi.org/10.1111/itor.12669}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/itor.12669}, author = {Sadati, Mir Ehsan Hesam and Aksen, Deniz and Necati Aras} } @article {1447, title = {A trilevel r-interdiction selective multi-depot vehicle routing problem with depot protection}, journal = {Computers \& operations research}, volume = {123}, year = {2020}, pages = {104996}, author = {Sadati, Mir Ehsan Hesam and Aksen, Deniz and Necati Aras} } @article {1439, title = {Assignment problem with conflicts}, journal = {Computers \& Operations Research}, volume = {111}, year = {2019}, pages = {214-229}, abstract = {

We focus on an extension of the assignment problem with additional conflict (pair) constraints in conjunction with the assignment constraints and binary restrictions. Given a bipartite graph with a cost associated with each edge and a conflict set of edge pairs, the assignment problem with conflict constraints corresponds to finding a minimum weight perfect matching without any conflicting edge pair. For example, some chemicals cannot be processed on close processors, food and toxic products cannot be stored neighboring locations at the same storage area, and machines cannot be sent to process jobs without satisfying some spatial constraints. Unlike the well-known assignment problem, this problem is NP-hard. We first introduce a realistic special class and demonstrate its polynomial solvability. Then, we propose a Branch-and-Bound algorithm and a Russian Doll Search algorithm using the assignment problem relaxations for lower bound computations, and introduce combinatorial branching rules based on the conflicting edges in an optimal solution of the relaxations. According to the extensive computational experiments we can say that the proposed algorithms are very efficient.

}, keywords = {Assignment problem, Branch-and-bound, Conflicts, integer programming}, issn = {0305-0548}, doi = {https://doi.org/10.1016/j.cor.2019.07.001}, url = {https://www.sciencedirect.com/science/article/pii/S0305054819301777}, author = {Temel {\"O}ncan and Zeynep {\c S}uvak and M. Hakan Aky{\"u}z and I. Kuban Altinel} } @article {1431, title = {A decomposition approach to solve the selective graph coloring problem in some perfect graph families}, journal = {Networks}, volume = {73}, year = {2019}, pages = {145-169}, abstract = {

Graph coloring is the problem of assigning a minimum number of colors to all vertices of a graph such that no two adjacent vertices receive the same color. The selective graph coloring problem is a generalization of the standard graph coloring problem; given a graph with a partition of its vertex set into clusters, the objective is to choose exactly one vertex per cluster so that, among all possible selections, the number of colors necessary to color the vertices in the selection is minimum. This study focuses on a decomposition based exact solution framework for selective coloring in some perfect graph families: in particular, permutation, generalized split, and chordal graphs where the selective coloring problem is known to be NP-hard. Our method combines integer programming techniques and combinatorial algorithms for the graph classes of interest. We test our method on graphs with different sizes and densities, present computational results and compare them with solving an integer programming formulation of the problem by CPLEX, and a state-of-the art algorithm from the literature. Our computational experiments indicate that our decomposition approach significantly improves solution performance in low-density graphs, and regardless of edge-density in the class of chordal graphs.

}, keywords = {chordal graphs, decomposition algorithm, generalized split graphs, integer programming, partition coloring, permutation graphs, selective graph coloring}, doi = {https://doi.org/10.1002/net.21850}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/net.21850}, author = {{\c S}eker, Oylum and Ekim, Tinaz and Z C Ta{\c s}k{\i}n} } @article {1434, title = {Minimum cost noncrossing flow problem on layered networks}, journal = {Discrete Applied Mathematics}, volume = {261}, year = {2019}, pages = {2-21}, abstract = {

In this work we focus on an extension of the minimum cost flow problem in layered networks. Feasible arc flows must satisfy a specific compatibility restriction in addition to flow balance and capacity restrictions. Namely, at most one of the crossing arcs is allowed to have positive flow on it. This variant of the minimum cost flow problem, which we call the minimum cost noncrossing flow problem, can frequently be encountered in real life. The determination of optimal temporal quay crane allocations to berthed vessels in container terminals, and optimal train schedules through the stations on the same railroad line are two examples. We first analyze the complexity of the problem and show that the noncrossing flow problem is in fact NP-complete in a layered network. Then, we introduce mixed-integer linear programming formulations and discuss a polynomially solvable special case. Next we show a sufficient condition for the existence of a crossing in an optimal solution, which can be used for preprocessing the arcs in order to reduce the problem size. Our computational experiments on a large test set show that our preprocessing algorithm can significantly reduce the number of arcs.

}, keywords = {integer programming, Layered networks, Network flows, Noncrossing flow}, issn = {0166-218X}, doi = {https://doi.org/10.1016/j.dam.2018.09.016}, url = {https://www.sciencedirect.com/science/article/pii/S0166218X18304815}, author = {I. Kuban Altinel and Necati Aras and Zeynep {\c S}uvak and Z C Ta{\c s}k{\i}n} } @article {1487, title = {Periodic Due Date Assignment with Family Setups}, journal = {INTERNATIONAL JOURNAL OF INDUSTRIAL ENGINEERING-THEORY APPLICATIONS AND PRACTICE}, volume = {26}, year = {2019}, pages = {0{\textendash}0}, issn = {-}, author = {Sertdemir, Sevilay and Ali Tamer {\"U}nal and D{\"U}ZG{\.I}T, ZEHRA} } @article {1500, title = {Small 1-defective Ramsey numbers in perfect graphs}, journal = {Discrete Optimization}, volume = {34}, year = {2019}, pages = {100548}, abstract = {

In this paper, we initiate the study of defective Ramsey numbers for the class of perfect graphs. Let PG be the class of all perfect graphs and R1PG(i,j) denote the smallest n such that all perfect graphs on n vertices have either a 1-dense i-set or a 1-sparse j-set. We show that R1PG(3,j)=j for any j>=2, R1PG(4,4)=6, R1PG(4,5)=8, R1PG(4,6)=10, R1PG(4,7)=13, R1PG(4,8)=15 and R1PG(5,5)=13. We exhibit all extremal graphs for R1PG(4,7)=13 (there are exactly three). We also obtain the 1-defective Ramsey number of order (4,7) in triangle-free perfect graphs, namely R1ΔPG(4,7)=12.

}, keywords = {-dense, -dependent, -sparse, Extremal graphs}, issn = {1572-5286}, doi = {https://doi.org/10.1016/j.disopt.2019.06.001}, url = {https://www.sciencedirect.com/science/article/pii/S1572528618301622}, author = {Ekim, Tinaz and John Gimbel and Oylum {\c S}eker} } @article {1161, title = {Efficient simulations for a Bernoulli mixture model of portfolio credit risk}, journal = {Annals of Operations Research}, volume = {260}, year = {2018}, pages = {113{\textendash}128}, author = {Ba{\c s}o{\u g}lu, {\.I}smail and Wolfgang H{\"o}rmann and Sak, Halis} } @article {1509, title = {Equimatchable claw-free graphs}, journal = {Discrete Mathematics}, volume = {341}, year = {2018}, pages = {2859-2871}, abstract = {

A graph is equimatchable if all of its maximal matchings have the same size. A graph is claw-free if it does not have a claw as an induced subgraph. In this paper, we provide the first characterization of claw-free equimatchable graphs by identifying the equimatchable claw-free graph families. This characterization implies an efficient recognition algorithm.

}, keywords = {Connectivity, Equimatchable graph, Factor-critical}, issn = {0012-365X}, doi = {https://doi.org/10.1016/j.disc.2018.06.043}, url = {https://www.sciencedirect.com/science/article/pii/S0012365X18302140}, author = {Saieed Akbari and Hadi Alizadeh and Ekim, Tinaz and Didem G{\"o}z{\"u}pek and Mordechai Shalom} } @article {1504, title = {Graphs of Edge-Intersecting Non-Splitting Paths in a Tree: Representations of Holes-Part II}, journal = {Discrete Mathematics and Theoretical Computer Science}, volume = {20}, year = {2018}, pages = {1b{\textendash}1b}, author = {Boyac{\i}, Arman and Ekim, Tinaz and Shalom, Mordechai and Zaks, Shmuel} } @article {1502, title = {The maximum cardinality cut problem in co-bipartite chain graphs}, journal = {Journal of Combinatorial Optimization}, volume = {35}, year = {2018}, month = {Jan}, pages = {250{\textendash}265}, issn = {1382-6905}, author = {Ekim, Tinaz and Boyac{\i}, Arman and Shalom, Mordechai} } @article {1475, title = {Substitution elasticities in an energy-augmented CES production function An empirical analysis for Turkey}, journal = {Journal of Economics and Political Economy}, volume = {5}, year = {2018}, month = {Jun}, pages = {234{\textendash}249}, issn = {2148-8347}, author = {K{\"u}{\c c}{\"u}k, Merve and G{\"u}rkan Kumbaro{\u g}lu and SARICA, KEMAL} } @article {1130, title = {Branch-cut-price algorithms for solving a class of search problems on general graphs}, journal = {Networks}, volume = {70}, year = {2017}, pages = {4-18}, doi = {http://doi.org/10.1002/net.21740}, author = {Z C Ta{\c s}k{\i}n and J. Cole Smith} } @conference {1185, title = {Linear-Time Generation of Random Chordal Graphs}, booktitle = {International Conference on Algorithms and Complexity}, year = {2017}, publisher = {Springer}, organization = {Springer}, author = {Oylum {\c S}eker and Pinar Heggernes and Ekim, Tinaz and Z. Caner Ta{\c s}k{\i}n} } @article {1506, title = {A polynomial-time algorithm for the maximum cardinality cut problem in proper interval graphs}, journal = {Information Processing Letters}, volume = {121}, year = {2017}, pages = {29-33}, abstract = {

It is known that the maximum cardinality cut problem is NP-hard even in chordal graphs. On the positive side, the problem is known to be polynomial time solvable in some subclasses of proper interval graphs which is in turn a subclass of chordal graphs. In this paper, we consider the time complexity of the problem in proper interval graphs, and propose a polynomial-time dynamic programming algorithm.

}, keywords = {Graph algorithms, Maximum cut, Proper interval graph}, issn = {0020-0190}, doi = {https://doi.org/10.1016/j.ipl.2017.01.007}, url = {https://www.sciencedirect.com/science/article/pii/S0020019017300133}, author = {Arman Boyac{\i} and Ekim, Tinaz and Mordechai Shalom} } @article {1505, title = {On two extensions of equimatchable graphs}, journal = {Discrete Optimization}, volume = {26}, year = {2017}, pages = {112-130}, abstract = {

A graph is said to be equimatchable if all its maximal matchings are of the same size. In this work we introduce two extensions of the property of equimatchability by defining two new graph parameters that measure how far a graph is from being equimatchable. The first one, called the matching gap, measures the difference between the sizes of a maximum matching and a minimum maximal matching. The second extension is obtained by introducing the concept of equimatchable sets; a set of vertices in a graph G is said to be equimatchable if all maximal matchings of G saturating the set are of the same size. Noting that G is equimatchable if and only if the empty set is equimatchable, we study the equimatchability defect of the graph, defined as the minimum size of an equimatchable set in it. We develop several inapproximability and parameterized complexity results and algorithms regarding the computation of these two parameters, a characterization of graphs of unit matching gap, exact values of the equimatchability defect of cycles, and sharp bounds for both parameters.

}, keywords = {Edge dominating set, Equimatchable graph, Gallai{\textendash}Edmonds decomposition, Minimum maximal matching, Parameterized complexity}, issn = {1572-5286}, doi = {https://doi.org/10.1016/j.disopt.2017.08.002}, url = {https://www.sciencedirect.com/science/article/pii/S1572528616301438}, author = {Zakir Deniz and Ekim, Tinaz and Tatiana Romina Hartinger and Martin Milani{\v c} and Mordechai Shalom} } @proceedings {1192, title = {The Analysis of Characteristic Dynamics of Stock Management Structure with a First Order Supply Line Delay}, journal = {34th International Conference of the System Dynamics Society}, year = {2016}, address = {Delft, the Netherlands}, author = {Mehmet S and Hakan Ya{\c s}arcan} } @article {1178, title = {Equimatchable graphs are C2k+ 1-free for k>= 4}, journal = {Discrete Mathematics}, volume = {339}, year = {2016}, pages = {2964{\textendash}2969}, author = {Dibek, Cemil and Ekim, Tinaz and G{\"o}z{\"u}pek, Didem and Shalom, Mordechai} } @article {1510, title = {Graphs of edge-intersecting and non-splitting paths}, journal = {Theoretical Computer Science}, volume = {629}, year = {2016}, pages = {40-50}, abstract = {

The families of Edge Intersection Graphs of Paths in a tree (resp. in a grid) EPT (resp. EPG) are well studied graph classes. Recently we introduced the class of graphs of Edge-Intersecting and Non-Splitting Paths in a Tree (ENPT) [5]. In this model, two vertices are adjacent if they represent two intersecting paths of a tree whose union is also a path. In this study we generalize this graph class by allowing the host graph to be an arbitrary graph. These are the graphs of Edge-Intersecting and Non-Splitting Paths ENP. Although the Edge Intersection Graphs of Paths in an arbitrary graph includes all graphs, we show that this is not the case for ENP. We also show that the class ENP coincides with the family of graphs of Edge-Intersecting and Non-Splitting Paths in a Grid (ENPG). Following similar studies for EPG graph class, we study the implications of restricting the number of bends of the individual paths in the grid. We show that such a restriction restricts the graph class. Specifically, by restricting the number of bends one gets an infinite sequence of classes such that every class is properly included in the next one.

}, keywords = {EPG graphs, EPT graphs, Intersection graphs}, issn = {0304-3975}, doi = {https://doi.org/10.1016/j.tcs.2015.10.004}, url = {https://www.sciencedirect.com/science/article/pii/S0304397515008750}, author = {Arman Boyac{\i} and Ekim, Tinaz and Mordechai Shalom and Shmuel Zaks} } @article {1170, title = {Graphs of edge-intersecting non-splitting paths in a tree: Representations of holes{\textemdash}Part I}, journal = {Discrete Applied Mathematics}, volume = {215}, year = {2016}, pages = {47{\textendash}60}, author = {Boyac{\i}, Arman and Ekim, Tinaz and Shalom, Mordechai and Zaks, Shmuel} } @proceedings {1193, title = {The Shifting the Burden Archetype: A Workforce and Task Backlog Management Game}, journal = {34th International Conference of the System Dynamics Society}, year = {2016}, address = {Delft, the Netherlands}, author = {G{\"u}ran SZ and Hakan Ya{\c s}arcan} } @article {1467, title = {Locating recycling facilities for IT based electronic waste in Turkey}, journal = {Journal of Cleaner Production}, volume = {105}, year = {2015}, month = {Oct}, pages = {324{\textendash}336}, issn = {09596526}, author = {Necati Aras and Aybek Korugan and B{\"U}Y{\"U}K{\"O}ZKAN FEYZ{\.I}O{\u G}LU, G{\"U}L{\c C}{\.I}N and S{\.I}VR{\.I}KAYA {\c S}ER{\.I}FO{\u G}LU, FUNDA and Erol, Ismail and Nurtani{\c s} Velio{\u g}lu, Meltem} } @article {908, title = {Metabolic connectivity as index of verbal working memory}, journal = {Journal of cerebral blood flow and metabolism}, volume = {35}, year = {2015}, month = {July}, pages = {1122{\textemdash}1126}, issn = {0271-678X}, doi = {10.1038/jcbfm.2015.40}, url = {http://dx.doi.org/10.1038/jcbfm.2015.40}, author = {Zou, Na and Chetelat, Gael and Mustafa Gokce Baydogan and Li, Jing and Fischer, Florian U and Titov, Dmitry and Dukart, Juergen and Fellgiebel, Andreas and Schreckenberger, Mathias and Yakushev, Igor} } @article {671, title = {An Integer Programming-Based Search Technique for Error-Prone Substructures of LDPC Codes}, journal = {AEU - International Journal of Electronics and Communications}, volume = {68}, year = {2014}, pages = {1097-1105}, doi = {10.1016/j.aeue.2014.05.012}, author = {Abdullah Sar{\i}duman and Ali Emre Pusane and Z C Ta{\c s}k{\i}n} } @article {ekcsiouglu2014save, title = {Save the Musicians! The Ergonomics of the Drumming}, journal = {Advances in Physical Ergonomics and Human Factors: Part II}, volume = {15}, year = {2014}, pages = {269}, publisher = {AHFE Conference}, author = {Mahmut Ek{\c s}io{\u g}lu and {\"O}zt{\"u}rk, N Kaan and {\c S}irin, Orkun} } @article {boyaci2013graphs, title = {Graphs of Edge-Intersecting Non-splitting Paths in a Tree: Towards Hole Representations}, year = {2013}, author = {Boyac{\i}, Arman and Ekim, Tinaz and Shalom, Mordechai and Zaks, Shmuel} } @article {bacsouglu2013optimally, title = {Optimally stratified importance sampling for portfolio risk with multiple loss thresholds}, journal = {Optimization}, volume = {62}, number = {11}, year = {2013}, pages = {1451{\textendash}1471}, publisher = {Taylor \& Francis}, author = {Ba{\c s}o{\u g}lu, {\.I}smail and Wolfgang H{\"o}rmann and Sak, Halis} } @mastersthesis {857, title = {Solving Integrated Berth Allocation And Crane Assignment Problem Using A Tabu Search Metaheuristic}, year = {2013}, author = {Zeynep {\c S}uvak} } @article {sak2012fast, title = {Fast simulations in credit risk}, journal = {Quantitative Finance}, volume = {12}, number = {10}, year = {2012}, pages = {1557{\textendash}1569}, publisher = {Routledge}, author = {Sak, Halis and Wolfgang H{\"o}rmann} } @article {TaskinEtAl2012, title = {Mixed-Integer Programming Techniques for Decomposing IMRT Fluence Maps Using Rectangular Apertures}, journal = {Annals of Operations Research}, volume = {196(1)}, year = {2012}, pages = {799-818}, doi = {http://dx.doi.org/10.1007/s10479-010-0767-1}, author = {Z C Ta{\c s}k{\i}n and J. Cole Smith and H. Edwin Romeijn} } @article {1476, title = {Modeling and analysis of a decentralized electricity market: An integrated simulation/optimization approach}, journal = {Energy}, volume = {44}, year = {2012}, pages = {830-852}, abstract = {

In this study, a model is developed to investigate the implications of an hourly day-ahead competitive power market on generator profits, electricity prices, availability and supply security. An integrated simulation/optimization approach is employed integrating a multi-agent simulation model with two alternative optimization models. The simulation model represents interactions between power generator, system operator, power user and power transmitter agents while the network flow optimization model oversees and optimizes the electricity flows, dispatches generators based on two alternative approaches used in the modeling of the underlying transmission network: a linear minimum cost network flow model and a non-linear alternating current optimal power flow model. Supply, demand, transmission, capacity and other technological constraints are thereby enforced. The transmission network, on which the scenario analyses are carried out, includes 30 bus, 41 lines, 9 generators, and 21 power users. The scenarios examined in the analysis cover various settings of transmission line capacities/fees, and hourly learning algorithms. Results provide insight into key behavioral and structural aspects of a decentralized electricity market under network constraints and reveal the importance of using an AC network instead of a simplified linear network flow approach.

}, keywords = {Alternative current optimum power flow, Electricity market modeling and design, Minimum cost network flow, Multi-agent simulation}, issn = {0360-5442}, doi = {https://doi.org/10.1016/j.energy.2012.05.009}, url = {https://www.sciencedirect.com/science/article/pii/S036054421200388X}, author = {Kemal Sar{\i}ca and G{\"u}rkan Kumbaro{\u g}lu and {\.I}lhan Or} } @inbook {ekcsiouglu2011heuristic, title = {Heuristic evaluation and usability testing: case study}, booktitle = {Internationalization, Design and Global Development}, year = {2011}, pages = {143{\textendash}151}, publisher = {Springer Berlin Heidelberg}, organization = {Springer Berlin Heidelberg}, author = {Mahmut Ek{\c s}io{\u g}lu and Kiris, Esin and \cCapar, Burak and Sel{\c c}uk, Murat N and Ouzeir, Selen} } @mastersthesis {seker_ms, title = {Modeling the Dynamics of Thyroid Hormones and Related Disorders}, year = {2011}, school = {Bo{\u g}azi{\c c}i University}, type = {MS}, author = {Oylum {\c S}eker} } @proceedings {seker, title = {Modeling the Dynamics of Thyroid Hormones and Related Disorders}, journal = {29th International Conference of the System Dynamics Society}, year = {2011}, author = {Oylum {\c S}eker and Yaman Barlas and Faruk Alag{\"o}l} } @conference {cseker2010controlling, title = {Controlling the Direction of a Model Helicopter}, booktitle = {The 28th International System Dynamics Conference, Seoul, Korea}, year = {2010}, publisher = {System Dynamics Society (http://www.systemdynamics.org/conferences/2010/index.htm)}, organization = {System Dynamics Society (http://www.systemdynamics.org/conferences/2010/index.htm)}, author = {Oylum {\c S}eker and Yasarcan, Hakan} } @article {aras2010designing, title = {Designing the reverse logistics network}, journal = {Closed-loop supply chains: new developments to improve the sustainability of business practices. Auerbach Publications}, year = {2010}, pages = {67{\textendash}97}, author = {Necati Aras and Boyaci, Tamer and Verter, Vedat and Ferguson, M and Souza, GC} } @article {erol2010exploring, title = {Exploring reverse supply chain management practices in Turkey}, journal = {Supply Chain Management: An International Journal}, volume = {15}, number = {1}, year = {2010}, pages = {43{\textendash}54}, publisher = {Emerald Group Publishing Limited}, author = {Erol, Ismail and Velioglu, Meltem Nurtanis and Serifoglu, Funda Sivrikaya and B{\"u}y{\"u}k{\"o}zkan, G{\"u}l{\c c}in and Necati Aras and Cakar, Nigar Demircan and Aybek Korugan} } @article {TaskinEtAl2010a, title = {Optimal Multileaf Collimator Leaf Sequencing in IMRT Treatment Planning}, journal = {Operations Research}, volume = {58}, number = {3}, year = {2010}, pages = {674{\textendash}690}, doi = {http://dx.doi.org/10.1287/opre.1090.0759}, author = {Z C Ta{\c s}k{\i}n and J. Cole Smith and H. Edwin Romeijn and James F. Dempsey} } @article {hormann2010t, title = {t-Copula generation for control variates}, journal = {Mathematics and Computers in Simulation}, volume = {81}, number = {4}, year = {2010}, pages = {782{\textendash}790}, publisher = {North-Holland}, author = {Wolfgang H{\"o}rmann and Sak, Halis} } @article {TaskinEtAl2009a, title = {Cutting Plane Algorithms for Solving a Stochastic Edge-Partition Problem}, journal = {Discrete Optimization}, volume = {6}, number = {4}, year = {2009}, pages = {420-435}, doi = {http://dx.doi.org/10.1016/j.disopt.2009.05.004}, author = {Z C Ta{\c s}k{\i}n and J. Cole Smith and Shabbir Ahmed and Andrew J. Schaefer} } @conference {Derflinger;Hoermann;Leydold;Sak:2009a, title = {Efficient Numerical Inversion for Financial Simulations}, booktitle = {Monte Carlo and Quasi-Monte Carlo Methods 2008}, year = {2009}, pages = {297{\textendash}304}, publisher = {Springer-Verlag}, organization = {Springer-Verlag}, address = {Heidelberg}, author = {Derflinger, Gerhard and Wolfgang H{\"o}rmann and Leydold, Josef and Sak, Halis} } @article {34, title = {Toward Development of Adaptive Service-Based Software Systems}, journal = {IEEE Transactions on Services Computing}, volume = {2}, year = {2009}, pages = {247-260}, abstract = {

The rapid adoption of service-oriented architecture (SOA) in many large-scale distributed applications requires the development of adaptive service-based software systems (ASBS) with the capability of monitoring the changing system status, analyzing, and controlling tradeoffs among various quality-of-service (QoS) aspects, and adapting service configurations to satisfy multiple QoS requirements simultaneously. In this paper, our results toward the development of adaptive service-based software systems are presented. The formulation of activity-state-QoS (ASQ) models and how to use the data from controlled experiments to establish ASQ models for capturing the cause-effect dynamics among service activities, system resource states, and QoS in service-based systems are presented. Then, QoS monitoring modules based on ASQ models and SOA-compliant simulation models are developed to support the validation of the ASBS design. The main idea for developing QoS adaptation modules based on ASQ models is discussed. An experiment based on a voice communication service is used to illustrate our results.

}, keywords = {Design concepts, distributed/Internet-based software engineering tools and techniques, methodologies, modeling methodologies, quality of services, services systems}, issn = {1939-1374}, doi = {http://doi.ieeecomputersociety.org/10.1109/TSC.2009.17}, author = {Stephen S. Yau and Nong Ye and Hessam S. Sarjoughian and Dazhi Huang and Auttawut Roontiva and Mustafa Gokce Baydogan and Mohammed A. Muqsith} } @conference {ekcsiouglu2008isometric, title = {Isometric grip strength distribution of a Turkish sample}, booktitle = {Proceedings of the XX Annual International Occupational Ergonomics and Safety Conference}, year = {2008}, pages = {20{\textendash}24}, publisher = {International Society of Occupational Ergonomics and Safety ISBN \# 97809654506-4-5}, organization = {International Society of Occupational Ergonomics and Safety ISBN \# 97809654506-4-5}, author = {Mahmut Ek{\c s}io{\u g}lu and Silahl{\i}, Baykar} } @article {ekim2008polarity, title = {Polarity of chordal graphs}, journal = {Discrete Applied Mathematics}, volume = {156}, number = {13}, year = {2008}, pages = {2469{\textendash}2479}, publisher = {Elsevier}, author = {Ekim, Tinaz and Hell, Pavol and Stacho, Juraj and de Werra, Dominique} } @article {ulusoy1997genetic, title = {A genetic algorithm approach to the simultaneous scheduling of machines and automated guided vehicles}, journal = {Computers \& Operations Research}, volume = {24}, number = {4}, year = {1997}, pages = {335{\textendash}351}, publisher = {Elsevier}, author = {Ulusoy, G{\"u}nd{\"u}z and Sivrikaya-{\c S}erifoǧlu, Funda and {\"U}mit Bilge} }