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Computations of Wave Energy by Stream Function Wave Theory (흐름함수파이론에 의한 파랑 에너지의 계산)

  • Lee, Jung Lyul;Pyun, Chong Kun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.6 no.2
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    • pp.67-75
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    • 1986
  • This paper introduces the nonlinear Stream Function Wave Theory for design waves efficiently to compute the wave energy and energy transport quantities and to analyze the effects of nonlinearities on them. The Stream Function Wave Theory was developed by Dean for case of the observed waves with assymmetric wave profiles and of the design waves with symmetric theoretical wave profiles. Dalrymple later improved the computational procedure by adding two Lagrangian constraints so that more efficient convergence of the iterative numerical method to a specified wave height and to a zero mean free surface displacement resulted. And the Stream Function coefficients are computed numerically by the improved Marquardt algorithm developed for this study. As the result of this study the effects of nonlinearities on the wave quantities of the average potential energy density, the average kinetic energy density result in overestimation by linear wave theory compared to the Stream Function Wave Theory and increase monotonically with decreasing $L^*/L_O$ and with increasing $H/H_B$. The effects of nonlinearities on the group velocity and the wavelength quantities result in underestimation by linear wave theory and increase monotonically with increasing $H/H_B$. Finally the effect of nonlinearity on the average total energy flux results in overestimation for shallow water waves and underestimation for deep water waves by linear wave theory.

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Improving the Accuracy of Early Diagnosis of Thyroid Nodule Type Based on the SCAD Method

  • Shahraki, Hadi Raeisi;Pourahmad, Saeedeh;Paydar, Shahram;Azad, Mohsen
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.1861-1864
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    • 2016
  • Although early diagnosis of thyroid nodule type is very important, the diagnostic accuracy of standard tests is a challenging issue. We here aimed to find an optimal combination of factors to improve diagnostic accuracy for distinguishing malignant from benign thyroid nodules before surgery. In a prospective study from 2008 to 2012, 345 patients referred for thyroidectomy were enrolled. The sample size was split into a training set and testing set as a ratio of 7:3. The former was used for estimation and variable selection and obtaining a linear combination of factors. We utilized smoothly clipped absolute deviation (SCAD) logistic regression to achieve the sparse optimal combination of factors. To evaluate the performance of the estimated model in the testing set, a receiver operating characteristic (ROC) curve was utilized. The mean age of the examined patients (66 male and 279 female) was $40.9{\pm}13.4years$ (range 15- 90 years). Some 54.8% of the patients (24.3% male and 75.7% female) had benign and 45.2% (14% male and 86% female) malignant thyroid nodules. In addition to maximum diameters of nodules and lobes, their volumes were considered as related factors for malignancy prediction (a total of 16 factors). However, the SCAD method estimated the coefficients of 8 factors to be zero and eliminated them from the model. Hence a sparse model which combined the effects of 8 factors to distinguish malignant from benign thyroid nodules was generated. An optimal cut off point of the ROC curve for our estimated model was obtained (p=0.44) and the area under the curve (AUC) was equal to 77% (95% CI: 68%-85%). Sensitivity, specificity, positive predictive value and negative predictive values for this model were 70%, 72%, 71% and 76%, respectively. An increase of 10 percent and a greater accuracy rate in early diagnosis of thyroid nodule type by statistical methods (SCAD and ANN methods) compared with the results of FNA testing revealed that the statistical modeling methods are helpful in disease diagnosis. In addition, the factor ranking offered by these methods is valuable in the clinical context.

Portfolio Efficient Transaction Choice Strategies based on the Global Electronic Commerce (효율적 거래포트폴리오의 선택에 의한 국제간 전자상거래방식의 전략적 활용방안)

  • Kim, Ki-Sun
    • International Commerce and Information Review
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    • v.3 no.2
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    • pp.1-16
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    • 2001
  • This study discusses some theoretical implications for efficient utilization of the global E-commerce in a world of uncertainty by beginning with measures of risk and return for the global E-commerce, and by moving to risk and return for a efficient transaction portfolio of many risky methods of transaction. Decision rules are developed to show how individuals choose optimal transaction portfolios that maximize their expected utility of wealth. First, the individuals will generally want to allocate positive amount to the global E-commerce, which requires that the expected marginal utility of wealth equals zero. Secondly, the optimal transaction portfolio will be determined by finding the point of tangency between the efficient trading line and the hightest indifference curve in the mean-variance plane. Thirdly, if the global E-commerce is positively correlated with wealth, it must have an expected return that is higher than the risk-free transaction methods in order to compensate for its risk. Fourthly, on the other hand, if the global E-commerce is negatively correlated with wealth, it will have an expected return that is less than the risk-free transaction methods. Finally, the valuation of global E-commerce depends on the degree of individual's risk aversion and the covariance between the expected return of total wealth and the return of global E-commerce.

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Surface Characteristics of Type II Anodized Ti-6Al-4V Alloy for Biomedical Applications

  • Lee, Su-Won;Jeong, Tae-Gon;Yang, Jae-Ung;Jeong, Jae-Yeong;Park, Gwang-Min;Jeong, Yong-Hun
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2017.05a
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    • pp.77-77
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    • 2017
  • Titanium and its alloys offer attractive properties in a variety of applications. These are widely used for the field of biomedical implants because of its good biocompatibility and high corrosion resistance. Titanium anodizing is often used in the metal finishing of products, especially those can be used in the medical devices with dense oxide surface. Based on SAE/AMS (Society of Automotive Engineers/Aerospace Material Specification) 2488D, it has the specification for industrial titanium anodizing that have three different types of titanium anodization as following: Type I is used as a coating for elevated temperature forming; Type II is used as an anti-galling coating without additional lubrication or as a pre-treatment for improving adherence of film lubricants; Type III is used as a treatment to produce a spectrum of surface colours on titanium. In this study, we have focused on Type II anodization for the medical (dental and orthopedic) application, the anodized surface was modified with gray color under alkaline electrolyte. The surface characteristics were analyzed with Focused Ion Beam (FIB), Scanning Electron Microscopy (SEM), surface roughness, Vickers hardness, three point bending test, biocompatibility, and corrosion (potentiodynamic) test. The Ti-6Al-4V alloy was used for specimen, the anodizing procedure was conducted in alkaline solution (NaOH based, pH>13). Applied voltage was range between 20 V to 40 V until the ampere to be zero. As results, the surface characteristics of anodic oxide layer were analyzed with SEM, the dissecting layer was fabricated with FIB method prior to analyze surface. The surface roughness was measured by arithmetic mean deviation of the roughness profile (Ra). The Vickers hardness was obtained with Vickers hardness tester, indentation was repeated for 5 times on each sample, and the three point bending property was verified by yield load values. In order to determine the corrosion resistance for the corrosion rate, the potentiodynamic test was performed for each specimen. The biological safety assessment was analyzed by cytotoxic and pyrogen test. Through FIB feature of anodic surfaces, the thickness of oxide layer was 1.1 um. The surface roughness, Vickers hardness, bending yield, and corrosion resistance of the anodized specimen were shown higher value than those of non-treated specimen. Also we could verify that there was no significant issues from cytotoxicity and pyrogen test.

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Detailed Deterioration Diagnosis and Analysis of Site Environment for the Taean Dongmunri Maaesamjonbulipsang (Rock-carved Standing Triad Buddha Statue), Korea (태안 동문리 마애삼존불입상의 정밀 훼손도 진단과 위치환경 분석)

  • Lee, Sun-Myung;Jun, Byung-Kyu;Shin, Eun-Jeong;Lee, Chan-Hee
    • Journal of Conservation Science
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    • v.27 no.4
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    • pp.381-393
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    • 2011
  • This study focus on the surface deterioration diagnosis based on the material characteristics of Taean Dongmunri Maaesamjonbulipsang(rock-carved standing triad Buddha Statue) and the weathering environment analysis. Rock materials of the triad Buddha is coarse-grained biotite granite which is composed mainly of quartz, K-feldspar, plagioclase, biotite and muscovite. The triad Buddha was serious surface irregularity(13.5%), exfoliation(12.3%) and discoloration(46.6%), and the physical characteristics using ultrasonic velocity appeared fourth grade (0.59, highly weathered). Korean style wooden shelter of the triad Buddha(closed type) maintained high humidity environment (daily mean; 86.6%) than exterior environment, and appeared the possibility of deterioration by freezing-thawing because the temperature showed below zero temperatures in winter. The shelter was changed from closed-type to open-type to relieve the moisture problem recently. But the moisture problem is yet to be solved because surface water flowing along northern wayside is flowed into triad Buddha. Therefore, environmental control will need to stop inflow of water into triad Buddha.

Use of Duckweed as a Protein Supplement for Breeding Ducks

  • Men, Bui Xuan;Ogle, Brian;Lindberg, Jan Erik
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.6
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    • pp.866-871
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    • 2002
  • An experiment was conducted at the experimental duck farm of Cantho University to determine the effects of feeding duckweed (Lemna minor) that replaced commercial protein supplements in diets for local and Cherry Valley breeding ducks. The experiment included a total of 180 ducks, with five treatments and three replicates and six breeding ducks (one male plus five females together) per replicate, for both local and exotic Cherry Valley ducks. The five diets were fed ad libitum and were based on rice byproducts supplemented with roasted soya bean meal plus dried fishmeal at levels of 100% (SF100, control), 75 (SF75), 50 (SF50), 25 (SF25) or zero (SF0) % of the protein in the control diet, corresponding to 18, 15, 13, 10 and 8% CP in the diets for both breeds, respectively. Fresh duckweed was supplied ad libitum for all treatments. These diets were fed to local breeding ducks from 7 to 12 months of age, and to exotic breeding ducks (Cherry Valley) from 8 to 13 months of age. Total mean daily dry matter (DM) intakes were 183, 178, 176, 177 and 174 g (p<0.05) for the local ducks, and 221, 208, 215, 219 and 210 g (p<0.01) for the exotic ducks for the SF100 (control), SF75, SF50, SF25 and SF0 diets, respectively. Laying rates of the local ducks were 66.5, 65.2, 62.9, 63.1 and 62.3%, and of the Cherry Valley ducks 61.9, 58.4, 58.9, 59.1 and 53.5% (p<0.001) for the control (SF100), SF75, SF50, SF25 and SF0 treatments, respectively. Fertile egg rates were 95.6, 95.6, 97.8, 97.8 and 92.2%, and hatchabilities 89.4, 80.6, 87.2, 88.6 and 77.8% (p<0.05) for the local breed, and 97.8, 97.8, 91.1, 92.2 and 90.0% (p<0.05) and 72.8, 74.7, 75.0, 74.3 and 76.7% for the Cherry Valley ducks for diets SF100, SF75, SF50, SF25 and SF0, respectively. Corresponding feed conversion ratios (dry matter basis) were 3.83, 3.82, 3.89, 4.01 and 3.96 kg feed per kg egg mass for the local ducks and 4.52, 4.56, 4.58, 4.73 and 5.02 kg feed per kg egg mass for the Cherry Valley ducks for the SF100, SF75, SF50, SF25 and SF0 treatments, respectively. Replacement of 100% of the protein supplement by fresh duckweed in the diets of the local laying ducks decreased the feed costs by 25% compared to the control diet.

The efficacy and safety of Montelukast sodium in the prevention of bronchopulmonary dysplasia

  • Kim, Sang Bum;Lee, Jang Hoon;Lee, Juyoung;Shin, Seung Han;Eun, Ho Sun;Lee, Soon Min;Sohn, Jin A;Kim, Han Suk;Choi, Byung Min;Park, Min Soo;Park, Kook In;Namgung, Ran;Park, Moon Sung
    • Clinical and Experimental Pediatrics
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    • v.58 no.9
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    • pp.347-353
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    • 2015
  • Purpose: The purpose of this study was to evaluate the efficacy and safety of Montelukast sodium in the prevention of bronchopulmonarydysplasia (BPD). Methods: The Interventional study was designed as a multicenter, prospective, and randomized trial, with open labeled and parallel-experimental groups, 66 infants were enrolled and allocated to either the case group (n=30) or the control group (n=36) based on gestational age (GA). Infants in the case group were given Montelukast sodium (Singulair) based on their body weight (BW). Zero week was defined as the start time of the study. Results: The incidence of moderate to severe BPD was not different between the groups (case group: 13 of 30 [43.3%] vs. control group: 19 of 36 [52.8%], P=0.912). Additionally, secondary outcomes such as ventilation index, mean airway pressure and resort to systemic steroids were not significantly different. There were no serious adverse drug reactions in either group, and furthermore the rate of occurrence of mild drug related-events were not significantly different (case group: 10 of 42 [23.8%] vs. control group: 6 of 48 (15.8%), P=0.414). Conclusion: Montelukast was not effective in reducing moderate or severe BPD. There were no significant adverse drug events associated with Montelukast treatment.

Bioequivalence Evaluation of the Tiropramide Formulation by GC/MS (티로프라미드 주사제의 생물학적 동등성 평가를 위한 GC/MS 방법)

  • Myung, Seung-Woon;Kim, Myungsoo;Kim, Hye-Young;Kwak, Hyun-Tae;Min, Hye-Ki;Sohn, Dong-Ryul;Hong, Young-Hun
    • Analytical Science and Technology
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    • v.14 no.3
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    • pp.221-229
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    • 2001
  • The bioequivalence study of two tiropramide products was evaluated in 16 health male volunteers following intra-muscular injection. Test product was Tiram$^{(R)}$ injection (S Pharm. Co, Ltd.) and reference product was Tiropa$^{(R)}$ injection(D Pharm. Co., Ltd.). The drug concentration in plasma was determined by GC/MS for over a period of 8 hours after injection. Analysis of variance reveal that there are no differences in AUC (area under the plasma concentration-time curve from time zero to infinity), Cmax (maximum plasma concentration) and Tmax (time to reach Cmax). The differences of mean AUC, Cmax and Tmax between two products were 0.73, -1.385 and -12.994%, respectively. Minimum detectable differences (%) at ${\alpha}=0.05$ were all less than 20% given as a guideline (10.05, 17.90 and 19.01% for AUC, Cmax and Tmax, respectively). From these results, the two formulations of tiropramide are bioequivalent and thus, may be prescribed interchangeably.

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Adaptive Discrete Wavelet Transform Based on Block Energy for JPEG2000 Still Images (JPEG2000 정지영상을 위한 블록 에너지 기반 적응적 이산 웨이블릿 변환)

  • Kim, Dae-Won
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.1
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    • pp.22-31
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    • 2007
  • The proposed algorithm in this paper is based on the wavelet decomposition and the energy computation of composed blocks so the amount of calculation and complexity is minimized by adaptively replacing the DWT coefficients and managing the resources effectively. We are now living in the world of a lot. of multimedia applications for many digital electric appliances and mobile devices. Among so many multimedia applications, the digital image compression is very important technology for digital cameras to store and transmit digital images to other sites and JPEG2000 is one of the cutting edge technology to compress still images efficiently. The digital cm technology is mainly using the digital image compression features so that those images could be efficiently saved locally and transferred to other sites without any losses. JPEG2000 standard is applicable for processing the digital images usefully to keep, send and receive through wired and/or wireless networks. The discrete wavelet transform (DWT) is one of the main differences to the previous digital image compression standard such as JPEG, performing the DWT to the entire image rather than splitting into many blocks. Several digital images m tested with this method and restored to compare to the results of conventional DWT which shows that the proposed algorithm get the better result without any significant degradation in terms of MSE & PSNR and the number of zero coefficients when the energy based adaptive DWT is applied.

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Factors Affecting Health Promotion Behavior of Apheresis Blood-Donors (성분헌혈자의 건강증진행위에 영향을 미치는 요인)

  • Hong Kyong Hee;Park Ho Ran
    • Journal of Korean Public Health Nursing
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    • v.19 no.1
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    • pp.41-52
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    • 2005
  • This study was designed to provide a base for nursing intervention to help apheresis blood-donors to perform health promotion behavior effectively by surveying their health promotion behavior and by analyzing the critical factors. The study subjects were 468 participants in platelet donation at a university hospital apheresis unit in Seoul. The data for this study were collected between May and June. 2002. by questionnaire. Data were analyzed by t-test, ANOVA. Scheffe test, Pearson correlation coefficient. and stepwise multiple regression. The results were as follows. 1. The degree of performance of health promotion behavior of the subjects was a total average score of $152.9\pm21.5$ points and a mean score of 2.7 points. The highest score was 'I have a good relationship with others' in the factor of self-actualization and interpersonal support. The lowest score was 'I have my blood pressure checked regularly' in the factor of health responsibility. 2. Considering the classification according to the subjects' general characteristics. the health promotion behavior score was significantly higher for soldiers than high school students, for religious believers than atheists. and for high class economic status than mid and low class economic status. Also the health promotion behavior score was higher for those who had made more than five blood donations than those who had made zero or one donation. and for those who had made more than four blood donations than for those who had made less than four blood donations in the previous times of apheresis blood donation. The score was also higher for those not having a relationship with recipient than those having a relationship. 3. The self-efficacy related to donation. general self-efficacy and self-esteem had a significant correlation with the performance in health promotion behavior. 4. The critical factors that influenced the health promotion behavior were explained by $35.6\%$ of the general self-efficacy and by $40.2\%$ of the total of self-efficacy related to donation, and previous times of apheresis blood donation. The health promotion behavior score of apheresis blood-donors differed according to job, religion, economic status, previous times of whole blood donation, previous times of apheresis blood donation, and relationship with recipient. The health promotion behavior and self-efficacy related to donation, general self-efficacy, and self-esteem showed significant positive correlation with one another. The general self-efficacy, self-efficacy related to donation, and previous times of apheresis blood donation appeared to be the significant predictive factors of health promotion behavior. Therefore, from these study results, it is necessary to establish more effective and organized nursing intervention strategies for the health promotion behavior of apheresis blood-donors.

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