Uluslararası İndeksli Yayınlar / International Indexed Publications

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2D UAV path planning with radar threatening areas using simulated annealing algorithm for event detection
(2018) Basbous, Bilal;
Path Planning for Unmanned Aerial Vehicles (UAVs) can be used for many purposes. However, the problem becomes more and more complex when dealing with a large number of points to visit for detecting and catching different type of events and simple threat avoidance such as Radar Areas. In the literature different type of algorithms (especially evolutionary algorithms) are preferred. In this project, Simulated Annealing (SA) Algorithm is used for solving the path planning problem. Firstly, problem is converted to a part of Travelling Salesman Problem (TSP), and then the solutions are optimized with the 2-Opt approach and other simple algorithms. The code is implemented in MATLAB by using its visualization. Circular avoidance approach is developed and applied with the Simulated Annealing in order to escape from circular radar threats. Tests have been made to observe the results of SA algorithm and radar threats avoidance approaches, where the results show that after a period of time, SA algorithm gives acceptable solutions with the capacities of escaping from radar area threats. Where SA algorithm gives better solutions in less period of time when there are no radar threats. Experimental results depicted that the proposed model can result in an acceptable solution for UAVs in sufficient execution time. This model can be used as an alternative solution to the similar evolutionary algorithms.
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5-Methylhydantoin: From isolated molecules in a low-temperature Aaon matrix to solid state polymorphs characterization
(2017-12) Nogueira, Bernardo.A.; Canotilho J.; Eusébio MES; Henriques MSC; Paixão JA; Fausto R.; ILDIZ, GÜLCE ÖĞRÜÇ
The molecular structure, vibrational spectra and photochemistry of 5-methylhydantoin (C4H6N2O2; 5-MH) were studied by matrix isolation infrared spectroscopy and theoretical calculations at the DFT(B3LYP)/6-311++G(d,p) theory level. The natural bond orbital (NBO) analysis approach was used to study in detail the electronic structure of the minimum energy structure of 5-MH, namely the specific characteristics of the σ and π electronic systems of the molecule and the stabilizing orbital interactions. UV irradiation of 5-MH isolated in argon matrix resulted in its photofragmentation through a single photochemical pathway, yielding isocyanic acid, ethanimine, and carbon monoxide, thus following a pattern already observed before for the parent hydantoin and 1-methylhydantoin molecules. The investigation of the thermal properties of 5-MH was undertaken by differential scanning calorimetry (DSC), polarized light thermal microscopy (PLTM) and Raman spectroscopy. Four different polymorphs of 5-MH were identified. The crystal structure of one of the polymorphs, for which it was possible to grow up suitable crystals, was determined by X-ray diffraction (XRD). Two of the additional polymorphs were characterized by powder XRD, which confirmed the molecules pack in different crystallographic arrangements.
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5-Methylhydantoin: from isolated molecules in a low-temperature argon matrix to solid state polymorphs characterization
(Amer Chemical Soc, 1155 16th St, Nw, Washington, Dc 20036 USA, 2017-07-20) Nogueira, Bernardo A.; Canotilho, J.; Eusebio, M. E. S.; Henriques, M. S. C.; Paixao, J. A.; Fausto, Rui; ILDIZ, GÜLCE ÖĞRÜÇ; 107326
The molecular structure, vibrational spectra and photochemistry of 5-methylhydantoin (C4H6N2O2; 5-MH) were studied by matrix isolation infrared spectroscopy and theoretical calculations at the DFT(B3LYP)/6-311++G(d,p) theory level. The natural bond orbital (NBO) analysis approach was used to study in detail the electronic structure of the minimum energy structure of 5-MH, namely the specific characteristics of the sigma and pi electronic systems of the molecule and the stabilizing orbital interactions. UV irradiation of 5-MH isolated in argon matrix resulted in its photofragmentation through a single photochemical pathway, yielding isocyanic acid, ethanimine, and carbon monoxide, thus following a pattern already observed before for the parent hydantoin and 1-methylhydantoin molecules. The investigation of the thermal properties of 5-MH was undertaken by differential scanning calorimetry (DSC), polarized light thermal microscopy (PLTM) and Raman spectroscopy. Four different polymorphs of 5-MH were identified. The crystal structure of one of the polymorphs, for which it was possible to grow up suitable crystals, was determined by X-ray diffraction (XRD). Two of the additional polymorphs were characterized by powder XRD, which confirmed the molecules pack in different crystallographic arrangements.
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A breakthrough in neuroscience needs a "Nebulous Cartesian System" Oscillations, quantum dynamics and chaos in the brain and vegetative system
(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2007-04) Güntekin, Bahar; BAŞAR, EROL; TR142226; TR204666
The Cartesian System is a fundamental conceptual and analytical framework related and interwoven with the concept and applications of Newtonian Dynamics. In order to analyze quantum processes physicist moved to a Probabilistic Cartesian System in which the causality principle became a probabilistic one. This means the trajectories of particles (obeying quantum rules) can be described only with the concept of cloudy wave packets. The approach to the brain-body-mind problem requires more than the prerequisite of modem physics and quantum dynamics. In the analysis of the brain-body-mind construct we have to include uncertain causalities and consequently multiple uncertain causalities. These multiple causalities originate from (1) nonlinear properties of the vegetative system (e.g. irregularities in biochemical transmitters, cardiac output, turbulences in the vascular system, respiratory apnea, nonlinear oscillatory interactions in peristalsis); (2) nonlinear behavior of the neuronal electricity (e.g. chaotic behavior measured by EEG), (3) genetic modulations, and (4) additional to these physiological entities nonlinear properties of physical processes in the body. The brain shows deterministic chaos with a correlation dimension of approx. D-2=6, the smooth muscles approx. D-2=3. According to these facts we propose a hyper-probabilistic approach or a hyper-probabilistic Cartesian System to describe and analyze the processes in the brain-body-mind system. If we add aspects as our sentiments, emotions and creativity to this construct, better said to this already hyper-probabilistic construct, this "New Cartesian System" is more than hyper-probabilistic, it is a nebulous system, we can predict the future only in a nebulous way; however, despite this chain of reasoning we can still provide predictions on brain-body-mind incorporations. We tentatively assume that the processes or mechanisms of the brain-body-mind system can be analyzed and predicted similar to the metaphor of '' finding the walking path in a cloudy or foggy day". This is meant by stating "The Nebulous Cartesian System" (NCS). Descartes, at his time undertaking his genius step, did not possess the knowledge of today's physiology and modem physics; we think that the time has come to consider such a New Cartesian System. To deal with this, we propose the utilization of the Heisenberg S-Matrix and a modified version of the Feynman Diagrams which we call "Brain Feynman Diagrams". Another metaphor to consider within the oscillatory approach of the NCS is the "string theory". We also emphasize that fundamental steps should be undertaken in order to create the own dynamical framework of the brain-body-mind incorporation; suggestions or metaphors from physics and mathematics are useful; however, the grammar of the brains intrinsic language must be understood with the help of a new biologically founded, adaptive-probabilistic Cartesian system. This new Cartesian System will undergo mutations and transcend to the philosophy of Henri Bergson in parallel to the Evolution theory of Charles Darwin to open gateways for approaching the brain-body-mind problem. (c) 2006 Published by Elsevier B.V.
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A capacity curve model for confined clay brick infills
(Springer, Van Godewijckstraat 30, 3311 Gz Dordrecht, Netherlands, 2016-03) Özkaynak, Hasan; Yüksel, Ercan; SÜRMELİ, MELİH; 40475; 175417; 154472
Experimental studies have proven that clay brick infills, confined with carbon-fiber-reinforced polymers (CFRP) in reinforced concrete (RC) frames, have some advantages in terms of stiffness, strength, energy dissipation capability and damage intensity. Owing to these advantages, existing infill walls in RC frames may be retrofitted with CFRP strips, especially in low-rise buildings in earthquake-prone areas. There is a gap in the literature concerning their behavior model, for use in structural analysis. A piecewise linear capacity curve model called "DUVAR'' is proposed here, which estimates the envelope of force-vs.-displacement hysteresis, depending on the data compiled from the literature and the completed experimental studies. A nonlinear shear spring element is utilized in the model to represent the bare and retrofitted infills. The ultimate shear strength and the corresponding displacement, the ratio of cracking stiffness to initial stiffness, the ratio of ultimate strength to cracking strength, and the ductility ratio are the five key parameters of the model. The model is validated against the experimental results of two sovereign studies. Finally, the model is employed in the performance evaluation of an existing three-story RC building to exemplify its straightforward application.
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A Certain Class of Harmonic Mappings Related to Functions of Bounded Boundary Rotation
(Eudoxus Press, Llc, 1424 Beaver Trail Drive, Cordova, Tn 38016 Usa, 2014-05) Yavuz Duman, Emel; Aydoğan, Melike; POLATOĞLU, YAŞAR; 199370; 111202; 35549
Let V(k) be the class of functions with bounded boundary rotation and let S-H be the class of sense-preserving harmonic mappings. In the present paper we investigate a certain class of harmonic mappings related to the function of bounded boundary rotation.
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A certain class of starlike log-harmonic mappings
(Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2014-11) Aydoğan, Melike; POLATOĞLU, YAŞAR; 35549; 199370
In this paper we investigate some properties of log-harmonic starlike mappings. For this aim we use the subordination principle or Lindelof Principle (Lewandowski (1961) [71). (C) 2014 Elsevier B.V. All rights reserved.
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A CNN based rotation invariant fingerprint recognition system
(Istanbul Unıv, Fac Engineering, Elektrik-Elektronik Mühendisliği Bölümü, Avcılar Kampüsü, İstanbul, 34320, Turkey, 2017) Çelik Mayadağlı, Tuba; Saatçı, Ertuğrul; Rifat, Edizkan; 10488; 16117; 16117
This paper presents a Cellular Neural Networks (CNN) based rotation invariant fingerprint recognition system by keeping the hardware implementability in mind. Core point was used as a reference point and detection of the core point was implemented in the CNN framework. Proposed system consists of four stages: preprocessing, feature extraction, false feature elimination and matching. Preprocessing enhances the input fingerprint image. Feature extraction creates rotation invariant features by using core point as a reference point. False feature elimination increases the system performance by removing the false minutiae points. Matching stage compares extracted features and creates a matching score. Recognition performance of the proposed system has been tested by using high resolution PolyU HRF DBII database. The results are very encouraging for implementing a CNN based fully automatic rotation invariant fingerprint recognition system.
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A combinatorial discussion on finite dimensional Leavitt path algebras
(Hacettepe Univ, Fac Sci, Hacettepe Univ, Fac Sci, Beytepe, Ankara 06800, Turkey, 2014) Esin, Songül; Güloğlu, İsmail; Kanuni, Müge; KOÇ, AYTEN; 112205; 145213
Any finite dimensional semisimple algebra A over a field K is isomorphic to a direct sum of finite dimensional full matrix rings over suitable division rings. We shall consider the direct sum of finite dimensional full matrix rings over a field K. All such finite dimensional semisimple algebras arise as finite dimensional Leavitt path algebras. For this specific finite dimensional semisimple algebra A over a field K, we define a uniquely determined specific graph - called a truncated tree associated with A - whose Leavitt path algebra is isomorphic to A. We define an algebraic invariant kappa(A) for A and count the number of isomorphism classes of Leavitt path algebras with the same fixed value of kappa(A). Moreover, we find the maximum and the minimum K-dimensions of the Leavitt path algebras. of possible trees with a given number of vertices and we also determine the number of distinct Leavitt path algebras of line graphs with a given number of vertices.
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A Combined Fuzzy AHP-goal Programming Approach to Assembly-Line Selection
(IOS PRESS, NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS, 2007) Ayağ, Zeki; Özdemir, Rifat Gürcan; TR141173; TR8785
In mass production, assembly-line balancing (ALB) problem has been a critical and repetitive issue for companies for long time. On the other hand, equipment selection for stations has also been another important problem at the design stage of an assembly-line system. In this paper, both problems are handled simultaneously. Therefore first, goal programming (GP) method, a well-suited technique is used to develop a preemptive formulation to joint both of the problems, when the nature of the problem consists of several conflicting objectives, and some mathematical constraints on solutions. Second, an AHP method based on fuzzy scales which is incorporated with the GP is also used due to the fact that it takes both qualitative and quantitative judgments of decision-maker(s) into consideration to rank the equipment alternatives for stations by weight. The fuzzy AHP as one of the most commonly used multiple-criteria decision making (MCDM) methods has been effectively used for more than decade in both academic research and practice, and takes the vagueness and uncertainty on judgments of decision-maker(s) into consideration due to the fact that the crisp pairwise comparison in the conventional AHP seems to insufficient and imprecise to capture the right judgments of decision-maker(s). In short, in this study, a combined fuzzy AHP-GP approach is proposed to evaluating assembly-line design alternatives with equipment selection. An integer GP formulation is constructed, which also uses the fuzzy AHP scores of equipment alternatives, and employs them as one of the goals. Then, the mathematical model is solved to find out the ultimate alternative in terms of the minimized equipment cost and the maximized preference measures of decision-maker(s). The proposed approach is also illustrated on a sample case study.
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A comparative analysis of sensory visual evoked oscillations with visual cognitive event related oscillations in Alzheimer's disease
(ELSEVIER IRELAND LTD, ELSEVIER HOUSE, BROOKVALE PLAZA, EAST PARK SHANNON, CO, CLARE, 00000, IRELAND, 2009-09-25) Yener, Görsev G.; Güntekin, Bahar; Tülay, Elif; BAŞAR, EROL; TR142226; TR142311; TR204666; TR143760
We compared visual evoked oscillatory responses of subjects with Alzheimer's disease (AD) (n = 22) to healthy elderly controls (n = 19) elicited by simple light stimuli. The visual evoked oscillatory responses in AD subjects without cholinergic treatment (n = 11) show significant differences (df = 2.38. F = 4.957, P = 0.012) from the controls and the AD subjects treated with a cholinesterase inhibitor (n = 11). Higher theta oscillatory responses in untreated AD subjects are seen on the electrode locations over bi-parietal and right occipital regions after simple light stimuli with less, if any, cognitive load. These changes were restricted to the theta frequency range only and are related to location, frequency bands and drug effects. In our previous work we observed that visual event related oscillations elicited after the visual stimuli with a higher cognitive load, i.e. an oddball target, display lower amplitudes: between controls and AD subjects in delta frequency band without a drug effect, over the left and mid-central region. These differences between the visual evoked oscillations and the visual event related oscillations imply that there are at least two different cognitive circuits that are activated upon visual stimuli in AD patients. (c) 2009 Published by Elsevier Ireland Ltd.
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A comparative performance analyze model and supplier positioning in performance maps for supplier selection and evaluation
(Elsevier Science Bv, Sara Burgerhartstraat 25, Po Box 211, 1000 AE Amsterdam, Netherlands, 2012) Bilişik, Mutlu Emir; Çağlar, Hatice Nazan; Alp Bilişik, Özge Nalan; 110809
In supply chain, supplier has an important role and in this situation supplier evaluation and selection is gained more significance for companies. So that, it is purposed to improve an evaluation model to evaluate and select suppliers more effectively by correlate with company's supply chain. For that reason, a form is designing to collect data from concerned company's personnel and performance measuring model which includes scoring methodology and correlation analysis that is called as "Performance-Effect" analysis in this study. With this model, it is proposed to divest supplier evaluation from its general evaluation concept by presenting alternative selection criteria, suppliers and methods for working with positioning of these in performance maps.
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A comparative study of auditory and visual event related coherences
(Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2012-09) Tülay, Elif; Turp Gölbaşı, Bilge; Güntekin, Bahar; BAŞAR, EROL; 142226; 204666
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A comparative study of the yellow dent and purple flint maize kernel components by Raman spectroscopy and chemometrics
(2019-05-15) Kabuk, Hayrunnisa Nur; Kaplan, Ekin Su; Halimoğlu, Gökhan; Fausto, Rui; ILDIZ, GÜLCE ÖĞRÜÇ
In this investigation the potential of micro-Raman spectroscopy, coupled to a simple, standard chemometric method (principal component analysis, PCA), as a fast, cheap, field method to investigate maize kernel components (endosperm, germ and peel) is demonstrated. Particular emphasis was given to the determination of the relative protein and amylose/amylopectin contents in maize endosperm of yellow dent and purple flint corn species, the two major maize varieties produced in Turkey. It is shown that the studied yellow dent corn type has a comparatively larger content of protein (3.4%) and a higher amylopectin/amylose ratio in the endosperm than the studied purple flint variety (a 11% decrease of amylopectin was found in going from the studied yellow dent to the purple flint corn), while the germs of the two species differ mostly by the presence of a slightly larger amount of starch in the case of the yellow dent corn, the oil composition of both species being identical within the resolution of the used method of analysis. The spectra of the maize peels reveal essentially the presence of cellulose and lignin in similar amounts in the two types of corn. (C) 2019 Elsevier B.V. All rights reserved.
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A Comparative Study to Determine the Effective Window Size of Turkish Word Sense Disambiguation Systems
(Springer, 233 Spring Street, New York, Ny 10013, United States, 2013) Adalı, Eşref; Tantuğ, Ahmet Cüneyd; İLGEN, BAHAR; 141812; 8786; 21833
In this paper, the effect of different windowing schemes on word sense disambiguation accuracy is presented. Turkish Lexical SampleDataset has been used in the experiments. We took the samples of ambiguous verbs and nouns of the dataset and used bag-of-word properties as context information. The experi-ments have been repeated for different window sizes based on several machine learning algorithms. We follow 2/3 splitting strategy (2/3 for training, 1/3 for test-ing) and determine the most frequently used words in the training part. After re-moving stop words, we repeated the experiments by using most frequent 100, 75, 50 and 25 content words of the training data. Our findings show that the usage of most frequent 75 words as features improves the accuracy in results for Turkish verbs. Similar results have been obtained for Turkish nouns when we use the most frequent 100 words of the training set. Considering this information, selected al-gorithms have been tested on varying window sizes {30, 15, 10 and 5}. Our find-ings show that Naive Bayes and Functional Tree methods yielded better accuracy results. And the window size +/-5 gives the best average results both for noun and the verb groups. It is observed that the best results of the two groups are 65.8 and 56% points above the most frequent sense baseline of the verb and noun groups respectively.
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A comparison of Gordon's functional health patterns model and standard nursing care in symptomatic heart failure patients: A randomized controlled trial
(W.B. Saunders, 2020-06) Türen, Sevda; Enç, Nuray
Background Heart failure (HF) is associated with poor quality of life and increased morbidity and mortality. Aim This study aimed to investigate effect of application of Gordon's functional health pattern (FHP) model in nursing care of symptomatic HF patients on quality of life, morbidity and mortality in the post-discharge 30-day. Methods This is a prospective randomized controlled study conducted in a single center. Experimental group received nursing care planned in accordance with Gordon's FHP model. 60 control and 60 experimental HF patients were included in the study. In the control group nursing care was given according to the standard protocol of the hospital whereas in the experimental group nursing care was given in accordance with Gordon's FHP model. Patients in both groups were followed up after discharge at 30th day. Results Mean Minnesota Living with Heart Failure Questionnaire score improved significantly in the experimental group compared to the control group at 30th day (40.2 ± 23.5 vs 62.3 ± 22.9 respectively, p = 0.001). Seven patients (11.7%) in the experimental group and 17 patients (28.3%) in the control group were readmitted in the post discharge 30-day (p = 0.02). Kaplan-Meier survival curve analysis revealed significant difference in 30-day event free survival rates between groups (log-rank p = 0.31). Conclusion Application of Gordon's FHP model in the nursing care of HF patients was associated with significantly improved quality of life, and reduced hospital readmission rates at 30th day. This was the only independent predictor of 30-day event free survival.
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A component-oriented process model
(IEEE Computer Soc, 10662 Los Vaqueros Circle, Po Box 3014, Los Alamitos, Ca 90720-1314 USA, 2003-07) Altunel, Yusuf; 141288
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A compressed sensing based approach on discrete algebraic reconstruction technique
(IEEE, 345 E 47th St, New York, Ny 10017 USA, 2015) Demircan Türeyen, Ezgi; Kamaşak, Mustafa Erşel; 237397; 27148
Discrete tomography (DT) techniques are capable of computing better results, even using less number of projections than the continuous tomography techniques. Discrete Algebraic Reconstruction Technique (DART) is an iterative reconstruction method proposed to achieve this goal by exploiting a prior knowledge on the gray levels and assuming that the scanned object is composed from a few different densities. In this paper, DART method is combined with an initial total variation minimization (TvMin) phase to ensure a better initial guess and extended with a segmentation procedure in which the threshold values are estimated from a finite set of candidates to minimize both the projection error and the total variation (TV) simultaneously. The accuracy and the robustness of the algorithm is compared with the original DART by the simulation experiments which are done under (1) limited number of projections, (2) limited view problem and (3) noisy projections conditions.
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A Conformational Analysis and Vibrational Spectroscopic Investigation on 1,2-bis(o-carboxyphenoxy) Ethane Molecule
(Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2012-01) Balcı, Kubilay; Yapar, Gönül; Akkaya, Yasemin; Koch, A.; Kleinpeter, E.; AKYÜZ, SEVİM; 54889; 119404; 175409; 10127
The minima on the potential energy surface of 1,2-bis(o-carboxyphenoxy)ethane (CPE) molecule in its electronic ground state were searched by a molecular dynamics simulation performed with MM2 force field. For each of the found minimum-energy conformers, the corresponding equilibrium geometry, charge distribution, HOMO-LUMO energy gap, force field, vibrational normal modes and associated IR and Raman spectral data were determined by means of the density functional theory (DFT) based electronic structure calculations carried out by using B3LYP method and various Pople-style basis sets. The obtained theoretical data confirmed the significant effects of the intra- and inter-molecular hydrogen bonding interactions on the conformational structure, force field, and group vibrations of the molecule. The same data have also revealed that two of the determined stable conformers, both of which exhibit pseudo-crown structure, are considerably more favorable in energy to the others and accordingly provide the major contribution to the experimental spectra of CPE. In the light of the improved vibrational spectral data obtained within the "SQM FF" methodology and "Dual Scale Factors" approach for the monomer and dimer forms of these two conformers, a reliable assignment of the fundamental bands observed in the experimental room-temperature IR and Raman spectra of the molecule was given, and the sensitivities of its group vibrations to conformation, substitution and dimerization were discussed. (C) 2011 Elsevier B.V. All rights
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A Cutting Sequencing Approach to Modular Manufacturing
(Emerald Group Publishing Limited, 2004) Özdemir, Rifat Gürcan; AKTİN, AYŞE TÜLİN; 109203
In this study, a two‐stage algorithm is developed for the cutting sequencing problem in a modular manufacturing system consisting of four basic workstations. Since the flexibility of the system is dependent upon the cutting stage of raw materials, the study focuses particularly on this workstation. In the first stage of the algorithm, an integer linear programming model is used to determine the number of hardboards that will be cut. The model is tested with two different objective functions. In the second stage, a heuristic which takes into account the due date of the products is developed to obtain the real‐time sequencing of these cutting patterns on the shop floor. The algorithm is further implemented in a furniture manufacturer that operates on a make‐to‐order basis. The results of the existing and proposed system are compared, and the proposed algorithm is found to provide a useful tool in such a real‐life planning problem.

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