Optimizing Flight Schedules by an Automated Decision Support System

In current air forces, due to different types of aircrafts and missions, lots of flight schedules are published every day. All flying units make their flight schedules each of which contain decisions of the best pilot-mission-aircraft triplet according to unit’s own constraints and rules. In this study, main objective is to build a decision support system to assist the schedulers in fighter squadrons. Scheduling in fighter squadrons are complex and time consuming due to the combination of the large number of constraints and limited number of schedulers. Also, dynamic environment of the operation area that increases uncertainty level of the problem makes flight scheduling a difficult job. For this reason, building flight schedules without any supplementary tools takes a large amount of time. Thus, air forces are in need of automated decision support systems for flight scheduling. The required Decision Support System is coded in Microsoft Excel Visual Basic to produce flight schedules which are now made manually. To generate feasible schedules, Greedy Randomized Adaptive Search Procedures is implemented and generated schedules are scored to attain best solution. Following that, performance of DSS and scoring method are evaluated to analyze solution technique

An in vitro comparison of different adhesive strategies on the micro push-out bond strength of a glass fiber post

Objectives: To evaluate in vitro the push-out bond strengths of a glass fiber post adhesively luted with self-etching resin based and self-adhesive luting cements, as well as modified application procedure of self-adhesive luting cements in combination with single step self-etch adhesives. Materials and methods: Fifty single-rooted human maxillary central incisor teeth were endodontically treated and divided into five groups (n=10). Glass fiber posts (RelyX Fiber Post) were cemented with the following materials: group 1: ED Primer II/Panavia F 2.0 (PAN); group 2: RelyX Unicem (RU); group 3: Maxcem (MC); group 4: Adper Prompt L-Pop (PLP)/RelyX Unicem; group 5: Optibond all-in-one (OB)/Maxcem. Bonded specimens were cut (1-mm-thick sections) and push-out tests were performed (crosshead-speed, 0.5 mm/min). Data were analyzed by one-way ANOVA followed by the Tukey-HSD test for post hoc comparisons at ? = 0.05. Results: The highest bond strength was recorded for groups 4 and 2, with no statistically significant differences among them (p>0.05). Group 4 showed significantly higher bond strength than group 1 (p<0.001), group 3 (p<0.0001) and group 5 (p<0.0001). Group 1 showed significantly higher bond strength than the group 3 (p<0.05). No statistically significant differences were observed among group 1 and group 2, group 1 and group 5, group 3 and group 5. Group 3 showed significantly lower push-out bond strength than the all other luting strategies except for the group 5. Conclusions: The push-out bond strength values of modified application procedure of self-adhesive luting cements (RU and MC) in combination with single step self-etch dentin adhesives (PLP and OB) did not improve the push-out bond strength of fiber post when compared with those where the conventional use of self-adhesive cements. © Medicina Oral S. L

The cytotoxic evaluation of mineral trioxide aggregate and bioaggregate in the subcutaneous connective tissue of rats

Objectives: The purpose of this study was to evaluate and compare the cytotoxic effects of ProRoot MTA and DiaRoot BA, a bioceramic nanoparticulate cement, on subcutaneous rat tissue. Study D esign: Fifty Sprouge Dawley rats were used in this study. Polyethylene tubes filled with ProRoot MTA and DiaRoot BioAggregate, along with a control group of empty, were implanted into dorsal connective tissue of rats for 7, 15, 30, 60, and 90 days. After estimated time intervals the rats were sacrificed. The specimens were fixed, stained with hematoxylin and eosin, and then evaluated under a light microscope for inflammatory reactions and mineralization. Results: All groups evoked a severe to moderate chronic inflammatory reaction at 7 and 15 days, which decreased with time. Both the MTA and BioAggregate groups showed similar inflammatory reactions, except at 90 days when MTA showed statistically significant greater inflammation (p>0.05). The MTA group showed foreign body reaction at all times. Compared to BioAggregate, MTA showed significantly more foreign body reaction at 60 and 90 days (p<0.0001). After 30 days foreign body reaction of BioAggregate decreased significantly. Both MTA and BioAggregate groups showed similar necrosis at 7 and 15 days (p=0.094 and p=0.186 respectively). No necrosis was observed after 15 days. Similarly there was no fibrosis after 30 days for both MTA and BioAggregate groups (p>0.05). Conclusions: Since DiaRoot BioAggregate showed significantly better results than MTA, we can conclude that it is more biocompatible. However, further studies are required to confirm this result

Surface hardness evaluation of different composite resin materials: influence of sports and energy drinks immersion after a short-term period

OBJECTIVES: This study evaluated the effect of sports and energy drinks on the surface hardness of different composite resin restorative materials over a 1-month period. MATERIAL AND METHODS: A total of 168 specimens: Compoglass F, Filtek Z250, Filtek Supreme, and Premise were prepared using a customized cylindrical metal mould and they were divided into six groups (N=42; n=7 per group). For the control groups, the specimens were stored in distilled water for 24 hours at 37º C and the water was renewed daily. For the experimental groups, the specimens were immersed in 5 mL of one of the following test solutions: Powerade, Gatorade, X-IR, Burn, and Red Bull, for two minutes daily for up to a 1-month test period and all the solutions were refreshed daily. Surface hardness was measured using a Vickers hardness measuring instrument at baseline, after 1-week and 1-month. Data were statistically analyzed using Multivariate repeated measure ANOVA and Bonferroni's multiple comparison tests (α=0.05). RESULTS: Multivariate repeated measures ANOVA revealed that there were statistically significant differences in the hardness of the restorative materials in different immersion times (p<0.001) in different solutions (p<0.001). The effect of different solutions on the surface hardness values of the restorative materials was tested using Bonferroni's multiple comparison tests, and it was observed that specimens stored in distilled water demonstrated statistically significant lower mean surface hardness reductions when compared to the specimens immersed in sports and energy drinks after a 1-month evaluation period (p<0.001). The compomer was the most affected by an acidic environment, whereas the composite resin materials were the least affected materials. CONCLUSIONS: The effect of sports and energy drinks on the surface hardness of a restorative material depends on the duration of exposure time, and the composition of the material

Optimizing warehouse logistics operations through site selection models : Istanbul, Turkey

This thesis makes a cost benefit analysis of relocating the outdated and earthquake damaged supply distribution center of the Turkish Navy. Given the dynamic environment surrounding the military operations, logistic sustainability requirements, rapid information technology developments, and budget-constrained Turkish DoD acquisition environment, the site selection of a supply distribution center is critical to the future operations and logistics supporting the Turkish Navy. Additionally, this thesis analyzes site selection alternatives through the use of three modeling techniques; the Center of Gravity Method, the Electre Method, and the Logical Decisions for Windows methodology. The results of the analysis indicate that the most advantageous location for the naval supply center is in the port city of Pendik.http://archive.org/details/optimizingwareho109451119Lieutenant Junior Grade, Turkish NavyApproved for public release; distribution is unlimited

Effects of Er:YAG Laser and Air Abrasion on the Microleakage of a Resin-Based Fissure Sealant Material

Objective: The aim of the present study was to evaluate the effects of different surface pre-treatment techniques on the microleakage of a resin-based fissure sealant material. Methods:Thirty-five molars were divided into the following seven groups based on the surface pre-treatment technique used:(a) Erbium:Yttrium Aluminium Garnet (Er:YAG) laser (7 W); (b) Er:YAG laser (7 W)+acid etching (with 37% phosphoric acid); (c) Er:YAG laser (5.5 W); (d) Er:YAG laser (5.5 W)+acid etching; (e) air abrasion+acid etching; (f) air abrasion; and (g) conventional acid etching. The sealant was placed according to the manufacturers' instructions and light-cured for 20 sec. The sealed teeth were thermocycled for 10,000 cycles (58-55 degrees C), then immersed in 5% methylene blue for 24 h and sectioned mesiodistally. Each section was analyzed and photographed using a light microscope. Microleakage was assessed quantitatively by the degree of dye penetration and also qualitatively, scored on a three-point rating scale. Data were analyzed by one-way analysis of variance (ANOVA) and the Kruskal-Wallis test. The level of significance was set at p < 0.05. Results:Regardless of the fissure morphology and penetration depth, enamel surfaces conditioned with Er:YAG laser irradiation exhibited significantly higher microleakage than those conditioned with air abrasion followed by acid etching, and those conditioned with conventional acid etching (p < 0.05). Air abrasion followed by acid etching, as well as conventional acid etching, provided a sufficient seal, whereas laser irradiation alone or in combination with acid etching exhibited higher microleakage than did the other groups. Conclusions: Conventional acid etching remains the most effective and the simplest technique

Effect of surface conditioning methods on the microtensile bond strength of repair composite to indirect restorative materials

This study evaluated the effect of surface conditioning methods on the microtensile bond strength (µTBS) of a restorative composite to indirect restorative materials. Blocks (5 × 5 × 4 mm3) (N = 72) of (a) Zirconia (In-Ceram Zirconia, Vita) (ZR), (b) lithium disilicate glass ceramic (IPS Empress II, Ivoclar Vivadent) (LD), (c) Indirect resin composite (Gradia, GC) (GR) were fabricated (n = 24 per group) and divided randomly into three groups: 1-Control: no conditioning, 2-Silane coupling agent, 3-Hydrofluoric acid (9.5%) (HF)+silane. Each block was duplicated in resin composite. The adhesion surfaces were conditioned with airborne-particle abrasion (110 µm Al2O3 particles). Half of the conditioned blocks received no bonding and the other half one coat of bonding (ED Primer II, Kuraray). Each conditioned block was bonded to a composite block with a resin luting agent (Panavia F2.0, Kuraray). The blocks were sectioned into 1 mm2 microsticks and tested for microtensile bond strength (µTBS) (0.5 mm/min) in a μTBS testing machine. Failure types were evaluated under stereomicroscope and Scanning Electron Microscope (SEM). Data were analyzed using three-way ANOVA, Bonferroni corrected and independent sample t-tests (p < 0.05). Significant effect of the bonding (p < 0.001) and surface conditioning (p < 0.001) were observed in all groups. The highest mean bond strength values were obtained in the bonded, HF etched and silanized groups of ZR, LD and GR (12.4 ± 2.9, 28.1 ± 1.5 and 27.2 ± 2 MPa, respectively). HF acid + silane increased the repair bond values in all materials. Majority of the failure types were adhesive for ZR group, whereas HF + silane conditioned LD and GR groups presented predominantly cohesive failures in the cement

Surface hardness of different restorative materials after long-term immersion in sports and energy drinks

The purpose of this study was to evaluate the effect of sports and energy drinks on the surface hardness of different restorative materials over a 6-month period. Forty-two disk-shaped specimens were prepared for each of the four restorative materials tested: Compoglass F, Filtek Z250, Filtek Supreme, and Premise. Specimens were immersed for 2 mm daily, up to 6 months, in six storage solutions (n=7 per material for each solution): distilled water, Powerade, Gatorade, X-IR, Burn, and Red Bull. Surface hardness was measured at baseline, after 1 week, 1 month, and 6 months. Data were analyzed statistically using repeated measures ANOVA followed by the Bonferroni test for multiple comparisons (alpha=0.05). Surface hardness of the restorative materials was significantly affected by both immersion solution and immersion period (p<0.001). All tested solutions induced significant reduction in surface hardness of the restorative materials over a 6-month immersion period