A particle swarm optimization for the job shop scheduling problems

Popülasyon temelli sezgisel yöntemlerden biri olan Parçacık Sürü Optimizasyonu (PSO), kuş ve balık sürülerinin sosyal davranışlarından etkilenerek geliştirilen yeni bir eniyileme yöntemidir. Bu makalede, zor çizelgeleme problemleri arasında yer alan Atölye Tipi Çizelgeleme problemlerinin çözümü için, bir PSO modeli, Değişken Komşuluk Arama yöntemi ile birlikte geliştirilmiştir. Oluşturulan bu model, tamamlanma zamanı performans ölçütüne göre literatürde yer alan bazı zor test problemleri üzerindeki sonuçları incelenmiş ve iyi sonuçlar veren diğer sezgisel yöntemlerin sonuçlarıyla karşılaştırılmıştır. Sonuçta genel olarak önerilen modelin diğer yöntemlere göre daha iyi veya eşdeğer seviyede olduğu görülmüştür.  Anahtar Kelimeler: Atölye tipi çizelgeleme, parçacık sürü optimizasyonu, sezgiseller.Particle Swarm Optimization (PSO) is one of the population based optimization technique inspired by social behavior of bird flocking and fish schooling. PSO inventers were inspired of such natural process based scenarios to solve the optimization problems. In PSO, each single solution, called a particle, is considered as a bird, the group becomes a swarm (population) and the search space is the area to explore. Each particle has a fitness value calculated by a fitness function, and a velocity of flying towards the optimum, food. All particles fly across the problem space following the particle nearest to the optimum. PSO starts with initial population of solutions, which is updated iteration-by-iteration. Therefore, PSO can be counted as an evolutionary algorithm besides being a metaheuristics method, which allows exploiting the searching experience of a single particle as well as the best of the whole swarm. In this paper, A PSO model for the job shop scheduling problem is proposed. In addition, a simple but efficient local search method called Variable Neighborhood Search (VNS) is embedded to the PSO model and applied to several hardest benchmark suites. The results for the PSO algorithm with VNS are also presented and compared with many efficient meta-heuristic algorithms in literature. As a final result, PSO with VNS results are generally found to be better than other results. Keywords: Job shop scheduling, particle swarm optimization, Meta-Heuristics

The comparison of the metaheuristic algorithms performances on airport gate assignment problem

Bu çalışma, 05-07 Eylül 2016 tarihleri arasında İstanbul[Türkiye]’da düzenlenen 19. European-Operational-Research-Societies Working Group on Transportation Meeting (EWGT)’da bildiri olarak sunulmuştur.The airport gate assignment problem (AGAP) is an important research area in air transportation planning and optimization. In this paper we study the airport gate assignment problem where the objectives are to minimize the number of ungated flights and the total walking distances. In order to solve the problem, we proposed a new tabu search (TS) algorithm which uses a probabilistic approach as an aspiration criterion. We compared two metaheuristics, namely, TS, and simulated annealing (SA). A greedy algorithm used as a benchmark. We compared the performances of the algorithms and analyzed at different problem sizes. Experimentations showed that the new proposed metaheuristic algorithm gave promising results.EURO Working Grp TransportatEMAY Int Eng & Consultancy Incİstanbul Teknik ÜniversitesiTürkiye Bilim ve Teknoloji Konsey

Comparison of Inflammation Biomarkers among Chronic Obstructive Pulmonary Disease Groups: A Cross Sectional Study

Background: The Global Initiative classification (GOLD) for chronic obstructive pulmonary disease (COPD), which relies on the practical issues of treatment of this complex and heterogeneous disease, may not be reliable in predicting disease severity and prognosis as the term of inflammation is excluded from the definition. Aim: The aim of this study was to determine systemic inflammatory markers in GOLD ABCD groups and to compare these parameters according to clinical and functional features. Methods: The study included 60 COPD patients and 59 healthy subjects. Comparisons were made with the pulmonary function test, transthoracic echocardiography and the six‑minute walk test (6MWT). The COPD assessment test (CAT), modified Medical Research Council (mMRC), and index scores of body mass index, airflow obstruction, dyspnea, and exercise capacity (BODE) were recorded. The systemic inflammatory state was assessed using C‑reactive protein, fibrinogen, tumor necrosis factor‑alpha (TNF‑α), interleukin (IL)‑6, IL‑8 and IL‑18. Results: The levels of all serum inflammatory markers were higher in the COPD group than in the control group. TNF‑α and IL‑6 were significantly higher in the symptomatic groups (B and D) than in the less symptomatic groups (A and C) (P < 0.05). Spirometric parameters were more severe in Group D, followed by groups C, B and A, respectively. The 6MWT and the BODE scores were worst in Group D, followed by groups B, C and A. Conclusion: The results suggest that bronchodilator treatment alone might be insufficient in Group B patients, as the systemic inflammatory markers in addition to exercise capacity and mortality predictors were at the worst level in Groups D and B

Prosthetic treatment of congenital hard and soft palate defects

Obturator prostheses are used to improve mastication, speech, and swallowing by reestablishing oronasal separation and aesthetics in maxillary defect patients. A sectional and magnetically retained functional removable speech bulb prosthesis was planned to treat the congenitally cleft hard and soft palates of this patient. The obturator part, localized into lateral nasal undercuts covered with sound mucosa, was used to retain the complete denture. Two pieces of the prosthesis were joined together by a magnet in the mouth. A special hinge mechanism was added to join the complete denture and functional velopharyngeal parts of the prosthesis for the treatment of velopharyngeal inadequacy. Sufficient retention was obtained, and no major complications were seen in the patient's prosthesis in periodic controls. © Copyright 2012 American Cleft Palate-Craniofacial Association

Effect of Surgical Drill Guide on Heat Generated From Implant Drilling

Purpose: The purpose of this study was to evaluate the heat generated in bone by 2 implant drill systems in vitro with and without using surgical drill guides. Materials and Methods: Temperature was measured with K type thermocouple in vitro using the bovine femoral cortical bone model. A constant drill load of 2.0 kg was applied throughout the drilling procedures via a drilling rig at a speed of 1,500 rpm. Two different implant drill systems-System A (with external irrigation) and System B (with both external and internal irrigation)-were evaluated. The samples were divided into 4 groups. System A test group 1 (TG1) included the following: 20 samples for drilling with surgical drill guides; control group 1 (CG1): 20 samples for classical implant site preparation. System B test group 2 (TG2) included the following: 20 samples for drilling with surgical drill guides; control group 2 (CG2): 20 samples for classical implant site preparation. Heat was measured at the final drill in the drilling sequence (4.2 and 4.4 mm). Thermocouples were placed at a 1-mm distance from the osteotomy area at depths of 3, 6, and 9 mm. Heat measurements were recorded out to 50 uses by a software program. Data were subjected to the Mann-Whitney U and Kruskal-Wallis tests. The ? level was set a priori at 0.05. Results: The mean maximum temperatures at the depths of 3, 6, and 9 mm using surgical drill guides were 34.2°, 39.7°, and 39.8°C, respectively, although without using surgical drill guides the values were 28.8°, 30.7°, and 31.1°C. A statistically significant difference was found at the depths of 3, 6, and 9 mm between using surgical drill guides and classical drilling procedure. Conclusions: From a heat generation standpoint, we conclude that preparing an implant site with using surgical drill guides generates heat more than classical implant site preparation regardless of the irrigation type. © 2009 American Association of Oral and Maxillofacial Surgeons

Protective effects of ibuprofen against caustic esophageal burn injury in rats

Purpose: The aim of this study was to investigate the efficacy of ibuprofen on the healing of esophagus and the prevention of stricture development after esophageal caustic injuries in rats. Materials and methods: Rats were divided into three groups as: group 1(sham), group 2(esophageal burn injury), group 3(injury + ibuprofen). In groups 2 and 3, a standard esophageal burn injury was created by applying 10% NaOH solution to distal esophagus of about 3 cm. To rats in the sham group, isotonic solution was given instead of NaOH. Ibuprofen (90 mg/kg/day) was given via oral route to group 3 rats. Normal saline as placebo was given via the same route to rats in groups 1 and 2. 28 days later, all the live rats were killed. The distal esophageal segments of all rats were removed and divided into two equal parts for biochemical and histopathologic examination. In the tissue samples, biochemically hydroxyproline and histopathologically collagen content and stenosis indices were evaluated for efficacy of treatment. Results: The hydroxyproline level (μg/mg wet tissue) in the groups was 1.54 ± 0.08, 4.82 ± 0.60, and 3.28 ± 0.27, respectively. The hydroxyproline level increased significantly in group 2 compared with group 1 (P < 0.01). Although the hydroxyproline level was significantly increased in group 3 compared with group 1, it decreased significantly in group 3 compared with group 2 (P < 0.05) by treatment of ibuprofen. In group 3, the collagen content score (1.50 ± 0.26) was significantly lower than in group 2 (2.62 ± 0.37) (P < 0.05). The stenosis index was found as 0.37 ± 0.02 in group 1, 0.84 ± 0.02 in group 2, and 0.67 ± 0.03 in group 3. The stenosis index in group 2 was significantly higher than group 1 and group 3 (P < 0.01). Although the stenosis index was significantly higher than in group 1, a significant decrease in stenosis index was found in group 3 compared with group 2, by ibuprofen treatment (P < 0.01). Conclusion: Based on these results, we concluded that the treatment with ibuprofen in acute phase esophageal burn injury has beneficial effects on healing of esophagus and may decrease the stricture formation. For these reasons, ibuprofen may effectively be used in the acute phase treatment of caustic esophagus injury and after esophageal dilatation procedures. © 2010 Springer-Verlag

in rats

The aim of this study was to investigate the efficacy of ibuprofen on the healing of esophagus and the prevention of stricture development after esophageal caustic injuries in rats.Rats were divided into three groups as: group 1(sham), group 2(esophageal burn injury), group 3(injury + ibuprofen). In groups 2 and 3, a standard esophageal burn injury was created by applying 10% NaOH solution to distal esophagus of about 3 cm. To rats in the sham group, isotonic solution was given instead of NaOH. Ibuprofen (90 mg/kg/day) was given via oral route to group 3 rats. Normal saline as placebo was given via the same route to rats in groups 1 and 2. 28 days later, all the live rats were killed. The distal esophageal segments of all rats were removed and divided into two equal parts for biochemical and histopathologic examination. In the tissue samples, biochemically hydroxyproline and histopathologically collagen content and stenosis indices were evaluated for efficacy of treatment.The hydroxyproline level (mu g/mg wet tissue) in the groups was 1.54 +/- A 0.08, 4.82 +/- A 0.60, and 3.28 +/- A 0.27, respectively. The hydroxyproline level increased significantly in group 2 compared with group 1 (P < 0.01). Although the hydroxyproline level was significantly increased in group 3 compared with group 1, it decreased significantly in group 3 compared with group 2 (P < 0.05) by treatment of ibuprofen. In group 3, the collagen content score (1.50 +/- A 0.26) was significantly lower than in group 2 (2.62 +/- A 0.37) (P < 0.05). The stenosis index was found as 0.37 +/- A 0.02 in group 1, 0.84 +/- A 0.02 in group 2, and 0.67 +/- A 0.03 in group 3. The stenosis index in group 2 was significantly higher than group 1 and group 3 (P < 0.01). Although the stenosis index was significantly higher than in group 1, a significant decrease in stenosis index was found in group 3 compared with group 2, by ibuprofen treatment (P < 0.01).Based on these results, we concluded that the treatment with ibuprofen in acute phase esophageal burn injury has beneficial effects on healing of esophagus and may decrease the stricture formation. For these reasons, ibuprofen may effectively be used in the acute phase treatment of caustic esophagus injury and after esophageal dilatation procedures

Protective effects of ibuprofen against caustic esophageal burn injury in rats.

PURPOSE: The aim of this study was to investigate the efficacy of ibuprofen on the healing of esophagus and the prevention of stricture development after esophageal caustic injuries in rats. MATERIALS AND METHODS: Rats were divided into three groups as: group 1(sham), group 2(esophageal burn injury), group 3(injury + ibuprofen). In groups 2 and 3, a standard esophageal burn injury was created by applying 10% NaOH solution to distal esophagus of about 3 cm. To rats in the sham group, isotonic solution was given instead of NaOH. Ibuprofen (90 mg/kg/day) was given via oral route to group 3 rats. Normal saline as placebo was given via the same route to rats in groups 1 and 2. 28 days later, all the live rats were killed. The distal esophageal segments of all rats were removed and divided into two equal parts for biochemical and histopathologic examination. In the tissue samples, biochemically hydroxyproline and histopathologically collagen content and stenosis indices were evaluated for efficacy of treatment. RESULTS: The hydroxyproline level (microg/mg wet tissue) in the groups was 1.54 +/- 0.08, 4.82 +/- 0.60, and 3.28 +/- 0.27, respectively. The hydroxyproline level increased significantly in group 2 compared with group 1 (P < 0.01). Although the hydroxyproline level was significantly increased in group 3 compared with group 1, it decreased significantly in group 3 compared with group 2 (P < 0.05) by treatment of ibuprofen. In group 3, the collagen content score (1.50 +/- 0.26) was significantly lower than in group 2 (2.62 +/- 0.37) (P < 0.05). The stenosis index was found as 0.37 +/- 0.02 in group 1, 0.84 +/- 0.02 in group 2, and 0.67 +/- 0.03 in group 3. The stenosis index in group 2 was significantly higher than group 1 and group 3 (P < 0.01). Although the stenosis index was significantly higher than in group 1, a significant decrease in stenosis index was found in group 3 compared with group 2, by ibuprofen treatment (P < 0.01). CONCLUSION: Based on these results, we concluded that the treatment with ibuprofen in acute phase esophageal burn injury has beneficial effects on healing of esophagus and may decrease the stricture formation. For these reasons, ibuprofen may effectively be used in the acute phase treatment of caustic esophagus injury and after esophageal dilatation procedures