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1.
Smokeless tobacco use is a significant health risk for carcinoma of the oropharynx, and has a high prevalence in the southern United States. To evaluate the potential demand for a smokeless tobacco cessation program, we surveyed patients attending the General Medicine Clinic of a Veterans Affairs Medical Center. The prevalence of smokeless tobacco use was 5.8%, which did not justify creation of a clinic-based cessation program. Since we observed adults using smokeless tobacco as a means to reduce or stop their smoking, smoking cessation programs should include counseling against smokeless tobacco use.  相似文献   
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We propose a new packet reservation multiple access (PRMA) scheme for the joint transmission of voice and data traffics in a microcellular medium. The collision resolution protocol within the system is based on a modification of the window random access algorithm, which has superior properties compared to the conventional slotted Aloha. The proposed algorithm, which we call packet reservation window multiple access (PRWMA), works in distinct modes for voice and data without prioritization, and the user performs slightly different operations depending on the information type. Simulation results show that PRWMA outperforms PRMA by a significant margin in terms of voice user capacity.  相似文献   
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This work presents an attempt related to the importance of the fact that the series resistance value is considered in calculating the inter-face state density distribution from the non-ideal forward bias current–voltage (I-V) characteristics of Au/n-Si Schottky barrier diodes (SBDs). To examine the consistency of this approach, Au/n-Si SBDs with Si bulk thicknesses of 200 and 400μm have been prepared. Both diodes showed non-ideal I-V behaviour with ideality factors of 1.14 and 1.12, respectively, and thus it has been thought that the diodes have a metal–interface layer–semiconductor configuration. At the same energy position near the bottom of the conduction band, the interface state density (N SS) values, without taking into account the series resistance value of the devices, are almost one order of magnitude larger than the N SS values obtained taking into account the series resistance value.  相似文献   
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Neural Computing and Applications - The Cash in Transit (CIT) deals with the money distribution and picking up between depot(s), central bank, bank branches, Automated Teller Machines (ATMs),...  相似文献   
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Ayyildiz HF  Kara H  Sherazi ST 《Lipids》2011,46(12):1181-1190
A non-aqueous flow injection method for determining free fatty acid (FFA) content in corn and sunflower oil samples was developed. A single-line manifold system was built by modification of an HPLC for flow injection analysis (FIA). Without pre-treatment, oil samples were injected into a n-propanol solution containing KOH and phenolphthalein (PHP). The main parameters, such as flow rate of carrier phase, length, geometry, inner diameters of the coils and reagent concentration were all optimized. The proposed FIA method was validated for precision, accuracy, linear region, limit of detection (LOD) and limit of quantification (LOQ). The intra- and inter-day measurements of the precision of the method were found to be within the limits of acceptance criteria (RSD < 1%), and were rugged when the method was performed by a different analyst. The linear concentration range was calculated as 0.09–1.50 and 0.07–1.40 FFA% for corn and sunflower oils, correspondingly. The LOD and LOQ were found to be 7.53 × 10−4–2.28 × 10−3 oleic acid % and 7.11 × 10−4–2.23 × 10−3 oleic acid % for corn and sunflower oils, respectively. The results were compared with those obtained by the AOCS (Ca-5a-40) method using statistical t and F tests, and a significant difference was not observed between the methods at a 95% confidence level. The proposed method is suitable for quality control of routine applications due to its simplicity, high sample throughput, and economy of solvents and sample, offering considerable promise as a low cost analytical system that needs minimum human intervention over long periods of time.  相似文献   
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Purpose: To compare the shear bond strengths of six different porcelain laminate veneer (PLV) materials cemented to enamel with two different MDP-containing resin cements. Materials and methods: Totally 120 disc specimens were fabricated with In-Ceram alumina (ICA), Turkom-CeraTM (TCR), IPS Empress (IPS), IPS Empress-II (IPS2), Finesse (FNS), and Ceramco-3 (CER) ceramic systems (n = 20). Sixty specimens were cemented with self-adhesive resin cement (Clearfil SA), and 60 specimens were cemented with self-etch resin cement (Panavia F2.0) to enamel. Thus, 120 PLV–enamel specimens were assigned to 12 experimental groups (ICA/Pv, ICA/Cf, TCR/Pv, TCR/Cf, IPS/Pv, IPS/Cf, IPS2/Pv, IPS2/Cf, CER/Pv, CER/Cf). Shear force was applied on PLV–enamel interfaces until failure. Obtained data were statistically analyzed with ANOVA and t-tests. Results: Obtained shear bond strength values (SBSV) ranged as follows, respectively; TCR/Cf (7.70 MPa), FNS/Cf (7.57 MPa), TCR/Pv (6.91 MPa), ICA/Pv (5.05 MPa), CER/Pv (4.75 MPa), IPS2/Cf (4.66 MPa), FNS/Pv (4.43 MPa), IPS2/Pv (3.97 MPa), CER/Cf (3.82 MPa), IPS/Pv (3.62 MPa), ICA/Cf (3.59 MPa), IPS/Cf (3.11 MPa). Highest SBSV were obtained in TCR groups (7.70 MPa for TCR/Cf and 6.91 MPa for TCR/Pv) and lowest SBSV were obtained in IPS groups (3.11 MPa for IPS/Cf and 3.62 MPa for IPS/Pv) in both resin cements. No significant bond strength difference was found between two resin cements. Conclusions: TCR groups showed highest SBSV; lowest SBSV were obtained with both IPS PLVs. The resin cement type did not significantly affect the bond strength value of a ceramic type, except for the Finesse system.  相似文献   
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The main goal of the present study was (i) to determine the formation of degradation products in cottonseed oil (CSO) blends during deep frying process by adsorption and high performance size exclusion chromatography techniques and (ii) to evaluate the impacts of food additives on total polar (TPC) and polymeric compound (PTAG) formation using a chemometric approach. In order to prepare the frying CSO blends; ascorbic palmitate, mixed tocopherols, dimethylpolysiloxane, lecithin and sesame oils were used as additives. To determine the real impacts of additives, a quarter-fraction factorial experimental design with two levels and five factors was used. The changes in TPC and PTAG data were carefully evaluated during 10 h of frying at 170 ± 5 °C with normal distribution (ND) graphs and analyzed using a one-way analysis of variance (ANOVA), followed by Tukey’s Post-hoc test (α = 0.05). The results indicated that the increasing values for TPC and PTAG during the frying processes for all blends, TPC and PTAG contents reached maximum levels of 16.37 and 6.01 % respectively, which are below the limit values stated by official authorities for the quality assessment of frying oils. The ANOVA test results were in good agreement with ND graphs and data indicated that the impact of mixed tocopherols was significant for TPC formation, meanwhile the impact of lecithin and ascorbic palmitate × dimethylpolysiloxane were significant for PTAG formation. Thus, the present study should be considered to be a very useful guide for developing new frying oil formulations based on CSO by using food additives.  相似文献   
9.
In supply chain management process, the firm select best supplier takes the competitive advantage to other companies. Thus, supplier selection is an important issue and with the multiple criteria decision-making approach, the supplier selection problem includes both tangible and intangible factors. This paper is aimed to present an integrated fuzzy and linear programming approach to the problem. Firstly, linguistic values expressed in trapezoidal fuzzy numbers are applied to assess weights and ratings of supplier selection criteria. Then a hierarchy multiple model based on fuzzy set theory is expressed and fuzzy positive and negative ideal solutions are used to find each supplier’s closeness coefficient. Finally, a linear programming model based on the coefficients of suppliers, buyer’s budgeting, suppliers’ quality and capacity constraints is developed and order quantities assigned to each supplier according to the linear programming model. The integrated model is illustrated by an example in a textile firm.  相似文献   
10.
Ultrasonic and air-stripping techniques for removal of carbon tetrachloride (CCl4) and 1,1,1-trichloroethane (1,1,1-TCA) from water were studied in batch experiments. Ultrasound (US) is effective for destroying organic compounds in aqueous solutions whereas air stripping (AS) efficiently transfers volatile compounds from the liquid to the gas phase. In simultaneous US and AS experiments, synergistic effects were observed and attributed to the effect of US on the mass transfer process. Using a photographic method, ultrasonic break up of gas bubbles and changes in gas holdup ratios were examined. In the two different gas-sparging systems studied, ultrasonic waves did not break up gas bubbles. In contrast, bubbles from the smaller porous size diffuser were coalesced due to sonication. In addition, both photographic and gas holdup experiments demonstrated that ultrasonic irradiation increased the gas holdup ratio. The enhancement observed in the removal of the compounds appeared to be due to this greater ultrasonic gas holdup ratio.  相似文献   
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