An iterative genetic algorithm for the assembly line worker assignment and balancing problem of type-II

In this study, we consider the assembly line worker assignment and balancing problem of type-II (ALWABP-2). ALWABP-2 arises when task times differ depending on operator skills and concerns with the assignment of tasks and operators to stations in order to minimize the cycle time. We developed an iterative genetic algorithm (IGA) to solve this problem. In the IGA, three search approaches are adopted in order to obtain search diversity and efficiency: modified bisection search, genetic algorithm and iterated local search. When designing the IGA, all the parameters such as construction heuristics, genetic operators and local search operators are adapted specifically to the ALWABP-2. The performance of the proposed IGA is compared with heuristic and metaheuristic approaches on benchmark problem instances. Experimental results show that the proposed IGA is very effective and robust for a large set of benchmark problems.     

Ordering and finding the best of K > 2 supervised learning algorithms

Given a data set and a number of supervised learning algorithms, we would like to find the algorithm with the smallest expected error. Existing pairwise tests allow a comparison of two algorithms only; range tests and ANOVA check whether multiple algorithms have the same expected error and cannot be used for finding the smallest. We propose a methodology, the multitest algorithm, whereby we order supervised learning algorithms taking into account 1) the result of pairwise statistical tests on expected error (what the data tells us), and 2) our prior preferences, e.g., due to complexity. We define the problem in graph-theoretic terms and propose an algorithm to find the "best" learning algorithm in terms of these two criteria, or in the more general case, order learning algorithms in terms of their "goodness." Simulation results using five classification algorithms on 30 data sets indicate the utility of the method. Our proposed method can be generalized to regression and other loss functions by using a suitable pairwise test.     

Effects of chemical and physico-chemical surface conditioning methods on the adhesion of resin composite to different mineral trioxide aggregate based cements

This study investigated the adhesion of resin composite to mineral trioxide aggregate based cements after different chemical and physico-chemical surface conditioning methods. Mineral trioxide aggregate based cements (Biodentine, ProRoot MTA, Imicryl MTA) were embedded in Teflon disks (N?=?180). After storing at 37?°C at 100% humidity for 72?h, substrate surfaces were polished using silicon carbide papers. Specimens were allocated to 3 groups to be conditioned with one of the following (n?=?15 per group): a) Adhesive resin (Clearfil SE Bond, CSE), b) Adhesive resin (Adper Single Bond 2, SB2), c) air-abrasion with 30?μm alumina coated with silica?+?silane?+?adhesive resin (ALB), d) no surface conditioning, control group (CON). Microhybrid resin composite (Filtek Z250) was applied on the conditioned substrate surfaces and photo-polymerized. After storage at 37?°C at 100% humidity for 24?h, adhesive interfaces were loaded under shear (1?mm/min) in a universal testing machine. After debonding failure types were analyzed. Data were analyzed using 2-way ANOVA and Tukey’s test (alpha = 0.05). SBS results were significantly affected by surface conditioning (p?<?0.05) and materials (p?<?0.05). Interaction terms were significant (p?<?0.05). Biodentine-ALB resulted in significantly higher SBS values (3.96?±?1.24) compared to those of other combinations, while ALB and SB2 resulted in no significant difference for ProRoot MTA and Imicryl MTA (p?>?.05). CSE (1.36?±?0.5- 1.98?±?0.76) did not significantly increase SBS for all MTA materials compared to the control group (0.8?±?0.52 – 2?±?0.91) (p?>?9.05). While CON groups resulted in exclusively adhesive failures, ALB presented the highest incidence of mixed failures for all materials tested (60–100%).     

EFFECT OF PRESWELLING ON SOXHLET AND SUPERCRITICAL GAS EXTRACTION OF A TURKISH LIGNITE

Preswelling of Mugla-Yatagan lignite with THF (Tetrahydrofuran) followed by removal of the swelling agents results in higher extract yields, probably because the solvent molecules had easier access to the expanded pore structure of the swollen lignite. On the other hand, the yields of supercritical THF extract of the same lignite sample indicated that during removal of the swelling agent the expanded pore structure had collapsed. The results show that higher extract yields might have been obtained by the combined effect of the expanded pore structure of the swollen lignite and the solvent power of the mixed solvent,i.e., of the mixture of swelling agent and supercritical extraction fluid.     

Anaemia and thrombocytopenia due to haemophagocytosis in a 7-month-old boy with galactosialidosis

There is a need for revising the current practice for treatment of acute tonsillitis in France, i.e., systematic antibiotic treatment. There are three main reasons for this revision: 1) group A betahemolytic streptococcus is involved in only 20% of acute tonsillitis (80% being viral); 2) rheumatic fever has become very rare; 3) efficient rapid diagnostic tests are now available, allowing a selection of patients with streptococcal tonsillitis who must be treated.     

Catalytic-kinetic spectrophotometric determination of vanadium （V） based on the Celestine blue-bromate-vanadium （V）-citric acid reaction

A novel sensitive and relatively selective kinetic method is presented for the determination of V(V) based on its catalytic effect on the oxidation reaction of Celestine blue by potassium bromate in the presence of citric acid as an activator.The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of Celestine blue at a maximum absorption wavelength of 540 nm between 0.5 and 9 min(the fixed-time method) in an H3PO4 medium at 45°C.The effect of various parameters such as con...     

Catalytic-kinetic spectrophotometric determination of vanadium (Ⅴ) based on the Celestine blue-bromate-vanadium (Ⅴ)-citric acid reaction

A novel sensitive and relatively selective kinetic method is presented for the determination of V(Ⅴ) based on its catalytic effect on the oxidation reaction of Celestine blue by potassium bromate in the presence of citric acid as an activator.The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of Celestine blue at a maximum absorption wavelength of 540 nm between 0.5 and 9 min (the fixed-time method) in an H3PO4 medium at 45℃.The effect of various parameters such as concentrations of H3PO4,citric acid,potassium bromate and Celestine blue,ionic strength,reaction temperature and time on the rate of V(Ⅴ) catalyzed reaction was studied.The method is free from the most interferences,especially from large amounts of V(Ⅳ).The decrease in absorbance is proportional to the concentration of V(Ⅴ) over the entire concentration range tested (0.025-1.25 μg·mL-1) with a detection limit of 6.80 μg·L-1 (according to statistical 3Sblank/k criterion) and a coefficient of variation (CV) of 1.78％ (for ten replicate measurements at 95％ confidence level).The proposed method suffers from a few interferences such as Cr(Ⅵ) and Hg(Ⅱ) ions.The method was successfully applied to the determination of V(Ⅴ) in river water,lake water,tap water,natural drinking water samples and a certified standard reference material such as SRM-1640 with satisfactory results.The vanadium contents of natural water samples were detected by using both linear calibration curve and standard addition curve methods.The recoveries of spiked vanadium (Ⅴ) into the certified standard water sample were found to be quantitative,and the reproducibility was satisfactory.It was observed that the results of the SRM 1640 were in good agreement with the certified value.     

The effect of controlled atmosphere storage on pickle production from pickling cucumbers cv. ‘Troy’

Fresh pickling cucumbers (cv. Troy) were stored for 30 days at 7°C and 90–95% relative humidity (RH) under different controlled atmosphere (CA) combinations, and samples taken at 0 (i.e., without storage), 10, 20 and 30 days of storage were processed to sweet pickle. At each sampling, physical and chemical analyses were carried out in the fresh pickling cucumbers to determine the changes in the quality with storage time. Besides, physical, chemical and sensory analyses were carried out in the pickles elaborated from the fresh samples taken at the same periods, after keeping at room temperature for 6 months, with the aim of determining CA and storage time effect on the final pickle quality. It was found that storage of cucumbers to be processed to pickle could be possible for less than 10 days at 7°C temperature and 90–95 RH under normal atmosphere (NA). However, physical and chemical analyses showed that storage period of fresh pickling cucumbers could be prolonged up to 30 days under the same storage conditions, if suitable atmosphere combinations are created. Nevertheless, it was concluded that restricting the storage period of fresh pickling cucumbers to 20 days could give better results after processing to pickle. An erratum to this article can be found at     

Improved Reconfiguration Algorithm for the Dual Ring Network by Token Reversal

An improved algorithm is proposed to further enhance the reliability of the dual-ring network over the existing reconfiguration algorithm in the case of topological alteration due to link failures. The improvement is caused by accommodating the reversal of token flow instead of the loopback operation.     

Decolorisation treatments of azo dye waste waters including dichlorotriazinyl reactive groups by using advanced oxidation method

Decolorisation treatments of azo dye waste waters, which include dichlorotriazinyl reactive groups, were investigated by using ultraviolet (UV) radiation and hydrogen peroxide at various exposure times. Decolorisation time decreased when UV radiation power and hydrogen peroxide concentration increased. Colour removal reached 98.0–99.5% by using this method. Some environmental parameters of decolorised waste water, such as biological oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC), total inorganic carbon (TIC), total carbon (TC), adsorbable organohalides (AOX), sulphate and chloride, were determined. It was concluded that TOC, COD and AOX decreased while BOD increased and sulphate ions remained unchanged. These results suggested that the dye molecules were totally destroyed and some of these decomposition products were removed as carbon dioxide and water to some degree.