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Öğe Balancing stochastic type-II assembly lines: chance-constrained mixed integer and constraint programming models(TAYLOR & FRANCIS LTD, 2020) Pinarbasi, Mehmet; Alakas, Haci MehmetIn the literature, line balancing is mostly investigated in deterministic environments. But production systems inevitably contain stochastic situations. In this study, the stochastic type-II assembly line balancing problem (ALBP) is considered. Firstly, a chance-constrained nonlinear mixed integer programming (MIP) formulation is developed from the well-known deterministic form. Then, a new linearized stochastic model is proposed by using some transformation approaches to reduce model complexity, and the model is solved. Finally, constraint programming (CP) models for deterministic ALBPs, nonlinear chance-constrained stochastic ALBPs and linearized chance-constrained stochastic ALBPs are developed, respectively. Problems from the literature are utilized to test the effectiveness of the proposed models and the results are compared with a bidirectional heuristic algorithm. The numerical results show that the CP models are more effective and successful for solving the stochastic ALBP. Some managerial implications are also suggested for industrial environments that consistently face ALBPs.Öğe A constraint programming approach to type-2 assembly line balancing problem with assignment restrictions(Emerald Group Publishing Ltd, 2019) Pinarbasi, Mehmet; Alakas, Haci Mehmet; Yuzukirmizi, MustafaPurpose Main constraints for an assembly line balancing problem (ALBP) are cycle time/number of stations and task precedence relations. However, due to the technological and organizational limitations, several other restrictions can be encountered in real production systems. These restrictions are called as assignment restrictions and can be task assignment, station, resource and distance limitations. The purpose of the study is to evaluate the effects of these restrictions on ALBP using constraint programming (CP) model. Design/methodology/approach A novel CP model is proposed and compared to mixed-integer programming (MIP) as a benchmark. The objective is to minimize the cycle time for a given number of stations. The authors also provide explicit anthology of the assignment restriction effects on line efficiency, the solution quality and the computation time. Findings The proposed approach is verified with the literature test instances and a real-life problem from a furniture manufacturing company. Computational experiments show that, despite the fact that additional assignment restrictions are problematic in mathematical solutions, CP is a versatile exact solution alternative in modelling and the solution quality. Practical implications - Assembly line is a popular manufacturing system in the making of standardized high volume products. The problem of assembly line balancing is a crucial challenge in these settings and consists of assigning tasks to the stations by optimizing one or more objectives. Type-2 AR-ALBP is a specific case with the objective function of minimizing the cycle time for a given number of stations. It further assumes assignment restrictions that can be confronted due to the technological limitations or the strategic decisions of the company management. This is especially encountered in rebalancing lines. Originality/value Several solution approaches such as mathematical modelling, heuristic and meta-heuristic are proposed to solve the ALBP in the literature. In this study, a new approach has been presented using CP. Efficient models are developed for Type-2 ALBP with several assignment restrictions. Previous studies have not considered the problem to the presented extent. Furthermore, to the best of the authors' knowledge, the paper is the first study that solves ALBP with assignment restrictions using CP.Öğe A constraint programming model for mixed model type 2 assembly line balancing problem(Pamukkale Univ, 2016) Alagas, Haci Mehmet; Pinarbasi, Mehmet; Yuzukirmizi, Mustafa; Toklu, BilalThis paper presents a new constraint programming model for mixed-model assembly line balancing problem. The proposed model minimizes the cycle time for a given number of stations. The proposed model is tested with literature problems and its performance is evaluated by comparing to mathematical model. Best obtained solution and elapsed CPU time are used as performance criteria. The experimental results show that the proposed constraint programming model performs well and can be used as an alternative modeling technique to solve the problem.Öğe Constraint programming model for resource-constrained assembly line balancing problem(SPRINGER, 2020) Alakas, Haci Mehmet; Pinarbasi, Mehmet; Yuzukirmizi, MustafaThe literature studies assume that resources used to be perform the tasks are certain and homogenous in any assembly line. However, tasks may need to be processed by general resource requirements in real life. These general resources could be classified by usage of resources such as simple or multiple, alternative and concurrent. The problem which is related to assignment of the task to any workstation and assignment of resources needed by the task simultaneously is defined as resource-constrained assembly line balancing problems (RCALBPs). In this study, a multiobjective model with minimization of cycle time and resource usage for a given number of stations is modeled to solve the RCALBP for the first time. Alternative and general resource types for tasks and using more than two resource type requirements are also considered. A constraint programming model is developed and solved to find the optimal solutions of these problems. The proposed models are tested with sample scenarios to show the effectiveness of the model.Öğe Design process model for flexible manufacturing systems and application of TAI(Gazi Univ, Fac Engineering Architecture, 2011) Pinarbasi, Mehmet; Yuzukirmizi, MustafaIn this paper, a systematic design process model is proposed to model Flexible Manufacturing Systems (FMS). Generally, FMS systems design is complicated and cost very high as installation phase. Therefore, technical analysis of system design should be exact and accurate even for the installation phase. At this stage, the proposed model is Integration Definition for Function Modeling (IDEF) diagram which is a structured design technique. Proposed model is exemplified with a practical example in TAI which is operating in the aerospace industry. The performance of the proposed model is analyzed using simulation and queueing network technique. In the performance analysis, test parameters are determined as service rates, number of servers, routing information and number of transporters and also performance parameters are determined cycle time and machine utilization.Öğe Evaluation of natech criteria in organized industrial zones: An application for Kirikkale province(Elsevier Sci Ltd, 2024) Guven, Emel; Pinarbasi, Mehmet; Alakas, Haci Mehmet; Eren, TamerNatural disasters are unexpected natural events that cause severe property loss and moral damage. T & uuml;rkiye has been exposed to many disasters due to its location. One of the disasters experienced is the Kahramanmaras , earthquake that occurred on February 6th, 2023, in the recent past. Two consecutive earthquakes caused significant loss of life and property. In addition, some technological accidents happened because of the earthquake. The biggest of these was the fire in the Iskenderun marina. After the earthquake, the big fire that started with the fire of the containers on the quay could be brought under control after a long effort and time. Although it is often overshadowed by natural disasters, technological accidents triggered by natural disasters (Natech) accidents can cause severe damage. Especially Organized Industrial Zones (OIZ) are in areas with high Natech risk. This study determined 10 criteria that will cause Natech accidents for OIZs by literature review. The Pythagorean Fuzzy Analytical Hierarchy Process (PFAHP) method is used to weight the criteria. Then, a ranking is made using The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method among the five sectors operating in Kirikkale OIZ and which may have Natech risk.Öğe Evaluation of the companies for applied education under fuzzy environment: a case in an industrial university(Springer London Ltd, 2023) Ciftci, Sema; Pinarbasi, Mehmet; Yazici, Emre; Alakas, Haci MehmetNowadays, the problem of university graduates being unemployed is gradually increasing. To keep down unemployment, universities are integrating the concept of applied education into their educational curricula. The concept of applied education brings with it the problem of the correct student-company matching. In this study, the company selection criteria were focused on to determine the companies that university students will be sent to within the scope of applied education. Company selection criteria are determined by experts in the field. However, the evaluation of experts with precise criteria values can be very challenging in the decision-making process. For this purpose, the criteria weights were calculated using the Pythagorean Fuzzy AHP method in this study. Evaluation of companies to which students will be matched for applied/workplace education is ranked with these fuzzy weights by using TOPSIS and PROMETHEE II methods. To evaluation the proposed decision process, a real case study is carried out in an industrial private university in Turkey. The case study results show that the proposed method can provide effective and consistent results in the evaluation of companies under fuzzy environment.Öğe Harvest optimization for sustainable agriculture: The case of tea harvest scheduling(Keai Publishing Ltd, 2023) Sarimehmet, Bedirhan; Pinarbasi, Mehmet; Alakas, Haci Mehmet; Eren, TamerTo ensure sustainability in agriculture, many optimization problems need to be solved. An important one of them is harvest scheduling problem. In this study, the harvest scheduling problem for the tea is discussed. The tea harvest problem includes the creating a harvest schedule by considering the farmers' quotas under the purchase location and factory capacity. Tea harvesting is carried out in cooperation with the farmer -factory. Factory management is interested in using its resources. So, the factory capacity, purchase location capacities and number of expeditions should be considered during the harvesting process. When the farmer's side is examined, it is seen that the real professions of farmers are different. On harvest days, farmers often cannot attend to their primary professions. Considering the harvest day preferences of farmers in creating the harvest schedule are of great importance for sustainability in agriculture. Two different mathematical models are proposed to solve this problem. The first model minimizes the number of weekly expeditions of factory vehicles within the factor and purchase location capacity restrictions. The second model minimizes the number of expeditions and aims to comply with the preferences of the farmers as much as possible. A sample application was performed in a region with 12 purchase locations, 988 farmers, and 3392 decares of tea fields. The results show that the compliance rate of farmers to harvesting preferences could be increased from 52% to 97%, and this situation did not affect the number of expeditions of the factory. This result shows that considering the farmers' preferences on the harvest day will have no negative impact on the factory. On the contrary, it was concluded that this situation increases sustainability and encouragement in agriculture. Furthermore, the results show that models are effective for solving the problem.(c) 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Öğe Integrated definition modeling and Taguchi analysis of flexible manufacturing systems: aircraft industry application(Springer London Ltd, 2013) Pinarbasi, Mehmet; Sel, Cagri; Alagas, Haci Mehmet; Yuzukirmizi, MustafaIn this paper, flexible manufacturing systems (FMS) are studied. Firstly, an FMS design approach is proposed using integrated definition for function methodology. A systematic layout design and performance evaluation scheme is presented and detailed using this modeling framework. Then, the proposed approach is carried out with a case study from an aircraft industry to convert an existing traditional production system to FMS. To improve the system performance, a simulation-based method with Taguchi approach consisting of multiproducts is utilized. The objective is to find the machine and the product mix that achieves the maximum utilization while minimizing the cycle time. FMS system performance has been greatly improved by determining the most advantageous level of system components. It has also shown that FMS is a practicable production system in aircraft industry.Öğe Operating room scheduling with surgical team: a new approach with constraint programming and goal programming(Springer, 2023) Gur, Seyda; Pinarbasi, Mehmet; Alakas, Haci Mehmet; Eren, TamerIn recent years, there has been a significant increase in health expenditures due to population growth. In this context, hospital administrators have started to look for ways to use existing resources effectively. Operating rooms are one of the most important units of a hospital. The efficient use of these units is seen as a decrease in cost items and an increase in revenues. At this point, it is aimed to use the operating rooms effectively in this study. The fact that it contains many uncertainties and many stakeholders in its structure complicates the solution process of the operating room scheduling problem. In this study, planning was made that considered the uncertainty in the operation times and the surgeons, nurses, and anesthesiologists in the surgical team. To solve the problem, the logical modeling power of the constraint programming method and the power of the goal programming method to stretch rigid constraints were utilized. In the first stage, the balanced assignment of the surgical team (surgeon-nurse-anesthesiologist) was carried out, while in the second stage, operations were assigned to the operating rooms. The proposed model was evaluated according to the operating rooms' utilization rates and the solution's effectiveness. The results showed that the proposed model successfully created an effective and efficient schedule.Öğe Railway security personnel scheduling problem considering personnel preferences(Springer, 2024) Gencer, Muhammed Abdullah; Alakas, Haci Mehmet; Pinarbasi, Mehmet; Eren, TamerThis study discusses the shift scheduling problem of security personnel, considering personnel preferences for 43 stations on four lines of the Ankara metro, which carries more than 10 million passengers monthly. Firstly, 751 security personnel have been distributed to four lines of the Ankara metro according to personnel needs. A survey is conducted among the personnel at the stations on each line, and they are asked to rank the stations they want to work at according to their preferences. The station preferences of the personnel are listed with increasing scoring in parallel with the order of preference. A goal programming model has been used to assign personnel to stations, considering personnel needs, operating rules, and personnel preference scoring at the stations. The main objective of the model is to minimize the personnel-preferred station scoring. As a result of the solution of the mathematical model solved separately for four lines, 24.23% of the personnel for the M1 (K & imath;z & imath;lay-Bat & imath;kent) line, 27.94% of the personnel for the M2 (K & imath;z & imath;lay-Koru) line, 23.32% of the personnel for the M3 (Bat & imath;kent-Sincan) line, and 35.85% of the personnel for the M4 (Ke & ccedil;i & ouml;ren-& Scedil;ehitler) line, are assigned to their first three preferences. Moreover, an important balance is achieved between personnel preferences. Few studies are in the literature on railway security personnel scheduling, and no studies that consider personnel preferences have been found in this field. This study, which considers personnel preferences, contributes to the literature.Öğe Ranking of sectors in organized industrial zones according to Natech risk criteria: An application for Gaziantep province in Türkiye(Elsevier Sci Ltd, 2024) Guven, Emel; Pinarbasi, Mehmet; Alakas, Haci Mehmet; Eren, TamerTechnological accidents triggered by natural disasters are called Natech accidents. Natech accidents have the impact of increasing the negative effects of disasters. One of the places at risk for a Natech accident is the Organized Industrial Zones (OIZs), where many industrial establishments are located. Although businesses within OIZs are evaluated in terms of security, Natech risk assessment is often ignored. This situation causes Natech accidents to occur. For these reasons, the study focused on evaluating OIZs regarding Natech risk. Many criteria such as electrical resources, natural gas, distance between buildings and so forth are taken into account in Natech's risk assessment. However, it is challenging to make clear decisions and predictions about these criteria due to the nature of the disaster. There is inherently uncertainty and confusion during and after a disaster. For this reason, using fuzzy sets to evaluate criteria is more appropriate. Therefore, the study uses Pythagorean fuzzy sets, which have a wider fuzzy evaluation area. This study also includes the evaluation of alternative sectors in terms of Natech risk. For this purpose, Pythagorean Fuzzy Analytic Hierarchy Process (PFAHP) and Pythagorean Fuzzy the Technique for Order of Preference by Similarity to Ideal Solution (PFTOPSIS) methods are used. OIZ in Gaziantep has the largest area compared to those in other cities in T & uuml;rkiye, is chosen as the application area of the study. As a result of the study, it is determined that the release of hazardous substances and flammable criteria is the most crucial criterion, and the most dangerous sector in terms of Natech risk is the chemical sector.