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11.
In this paper, we study the Cutting Stock Problem with Setup Cost (CSP-S) which is a more general case of the well-known Cutting Stock Problem (CSP). In the classical CSP, one wants to minimize the number of stock items used while satisfying the demand for smaller-sized items. However, the number of patterns/setups to be performed on the cutting machine is ignored. In most cases, one has to find the trade-off between the material usage and the number of setups in order to come up with better production plans. In CSP-S, we have different cost factors for the material and the number of setups, and the objective is to minimize total production cost including both material and setup costs. We develop a mixed integer linear program and analyze a special case of the problem. Motivated by this special case, we propose two local search algorithms and a column generation based heuristic algorithm. We demonstrate the effectiveness of the proposed algorithms on the instances from the literature.  相似文献   
12.
Can Ekici  Ismail Teke 《Mapan》2018,33(3):233-240
Solar radiation is the main energy source for activities in the earth. It is important that the solar radiation values are known accurately. In cases where parameters about solar radiation cannot be measured, solar radiation estimation models are used. These are mathematical functions derived from the measured meteorological parameters. In this study, temperature-based estimation models that commonly used in the literature were examined, and uncertainty analysis of the models were applied. These solar radiation estimation models are Allen model, Hargreaves model, Chen model and Bristow–Campbell model. These models calculate the total global solar radiation with the difference between the maximum and minimum air temperatures. Measurement uncertainty budgets of the models and an example calculation can be found in the study.  相似文献   
13.
A radiation code based on the method of lines (MOL) solution of the discrete ordinates method (DOM) for transient three-dimensional radiative heat transfer in rectangular enclosures for use in conjunction with a computational fluid dynamics (CFD) code based on the same approach was developed. Assessment of the predictive accuracy of the code by benchmarking its steady-state solutions against exact solutions on one- and three-dimensional test problems shows that the MOL solution of the DOM provides accurate and computationally efficient solutions for radiative heat fluxes and source terms and can be used with confidence in conjunction with CFD codes for transient problems.  相似文献   
14.
Recently, strategies beyond pharmacological and psychological treatments have been developed for the management of obsessive-compulsive disorder (OCD). Specifically, repetitive transcranial magnetic stimulation (rTMS) has been employed as an adjunctive treatment in cases of treatment-refractory OCD. Here, we investigate six weeks of low frequency rTMS, applied bilaterally and simultaneously over the sensory motor area, in OCD patients in a randomized, double-blind placebo-controlled clinical trial. Twenty-two participants were randomly enrolled into the treatment (ACTIVE = 10) or placebo (SHAM = 12) groups. At each of seven visits (baseline; day 1 and weeks 2, 4, and 6 of treatment; and two and six weeks after treatment) the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) was administered. At the end of the six weeks of rTMS, patients in the ACTIVE group showed a clinically significant decrease in Y-BOCS scores compared to both the baseline and the SHAM group. This effect was maintained six weeks following the end of rTMS treatment. Therefore, in this sample, rTMS appeared to significantly improve the OCD symptoms of the treated patients beyond the treatment window. More studies need to be conducted to determine the generalizability of these findings and to define the duration of rTMS’ clinical effect on the Y-BOCS. Clinical Trial Registration Number (NCT) at www.clinicaltrials.gov: NCT00616486.  相似文献   
15.
A simple, precise, accurate, and validated reverse-phase HPLC method was developed for the determination of melamine in milk (pasteurized and UHT milk) and dairy products (powdered infant formula, fruit yogurt, soft cheese, and milk powder). Following extraction with acetonitrile:water (50:50, vol/vol), samples were purified by filter (0.45 μm), separated on a Nucleosil C8 column (4.6 mm × 250 mm, 3 μm) with acetonitrile:10 mmol/L sodium L-octane sulfonate (pH 3.1; 15:85, vol/vol) as mobile phase at a flow rate of 1 mL/min, and determined by a photodiode array detector. A linear calibration curve was obtained in the concentration range from 0.05 to 5 mg/kg. Milk and dairy products were fortified with melamine at 4 levels producing average recovery yields of 95 to 109%. The limits of detection and quantification of melamine were 35 to 110 and 105 to 340 μg/kg, respectively. The method was then used to analyze 300 samples of milk and dairy products purchased from major retailers in Turkey. Melamine was not found in infant formulas and pasteurized UHT milk, whereas 2% of cheese, 8% of milk powder, and 44% of yogurt samples contained melamine at the 121, 694±146, and 294±98 μg/kg levels, respectively. These findings were below the limits set by the Codex Alimentarius Commission and European Union legislation. This is the first study to confirm the existence of melamine in milk and dairy products in Turkey. Consumption of foods containing these low levels of melamine does not constitute a health risk for consumers.  相似文献   
16.
In this study, performance of cryogenically treated M35 high speed steel (HSS) twist drills in drilling of AISI 304 and 316 stainless steels was evaluated in terms of thrust force, surface roughness, tool wear, tool life, and chip formation. To present the differences in tool performance between untreated and treated drills, and machinability between AISI 304 SS and AISI 316 SS, a number of experiments were performed at different combinations of cutting speed, and feed rate. As the results of the conducted experiments, the treated drills showed better performance than untreated drills in terms of thrust force, surface roughness, and tool wear and tool life for both types of stainless steels. Tool lives of treated HSS drills in drilling of AISI 304 SS and AISI 316 SS improved 32% and 14%, respectively, when compared with untreated drills. Experimental results also showed that machinability of AISI 304 SS was harder than the machinability of AISI 316 SS.  相似文献   
17.
Akyildiz  Ian F.  Ekici  Eylem  Yue  Gaofeng 《Wireless Networks》2003,9(5):535-544
In this paper, a distributed multicast routing scheme is introduced for multi-layered satellite IP networks, which include GEO, MEO, and LEO layers. This scheme aims to minimize the total cost of multicast trees in the satellite network. Multicast trees are constructed and maintained in the dynamic satellite network topology in a distributed manner. Simulation results are provided to evaluate the performance of the new scheme in terms of end-to-end delay and multicast tree cost.  相似文献   
18.
Phenolic composition of the European cranberrybush (ECB) (Viburnum opulus L.) juice was determined using high‐performance liquid chromatography. The juice contained 2037 mg kg?1 chlorogenic acid, which was 54% of total phenolics, and several other phenolics such as (+)‐catechin, (?)‐epicatechin, cyanidin‐3‐glucoside, cyanidin‐3‐rutinoside and six different glucosides of quercetin. Because of its strong astringent taste, the juices were treated with various doses of two different types of activated carbons (Granucol Bi and Granucol Ge) in order to remove phenolic compounds. Results revealed that both types of activated carbons were equally effective on astringency removal (P < 0.01). A 20–30% reduction in total phenolics was achieved by application of 2.0–3.0 g L?1 activated carbon which also removed unpleasant taste and odour.  相似文献   
19.
Redox polymerization of methylmethacrylate (MMA) using Ce(IV) with poly(oxyethylene) having azo and hydroxy functions was carried out to yield methylmethacrylate-ethylene glycol block copolymers with labile azo linkages in the main chain. These prepolymers were used to initiate the radical polymerization of styrene through the thermal decomposition of the azo group, resulting in the formation of multiblock copolymers. Successful blocking has been confirmed by fractional precipitation, a strong change in the molecular weight distribution and spectral measurements.  相似文献   
20.
120 consecutive appendicectomies and 20 appendices from medicolegal autopsies were studied. The cases were grouped as. A: Acute appendicitis. B: Acute presentation, not diagnostic of acute appendicitis C: Elective appendicectomies D: Normal appendices from autopsies. Eosinophils and mast cells were counted in the muscularis, in Giemsa stained sections. The mean eosinophil and mast cell counts per mm2 were--A. 215.9; 26.5. B. 66.0; 32.1. C. 6.7; 25.8. D. 4.2; 19.6 respectively. Eosinophil count is significantly higher in A compared to others (p < 0.0001) and there was no range overlap with C and D. B is a heterogenous group with 37.5% having eosinophil counts in the range seen in A. Cases with mural eosinophil showed histological evidence of mast cell degranulation. Eosinophil infiltration of the muscularis is an early event universally seen in acute appendicitis. It is possible that the disease is triggered by Type I Hypersensitivity, and that infection is a later consequence.  相似文献   
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