• Journal of applied mathematics & informatics
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• 제6권1호
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• pp.51-64
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• 1999

We give a new characterization of the solutions set of the general (inconsistent) linear least-squares problem using the set of linit-points of an extended version of the classical Daczmarz's pro-jections method. We also obtain a "step error reduction formula" which in some cases can give us apriori information about the con-vergence properties of the algorithm. Some numerical experiments with our algorithm and comparisons between it and others existent in the literature are made in the last section of the paper.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2007년도 추계학술발표대회 논문집
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• pp.183-186
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• 2007

In modern society, sense of crisis from environmental destruction caused by rapid industrial development, economic growth and improvement of educational level and medicine made environmental preservation and comfortable residential environment a necessary and sufficient condition. Since government conducted 'green building rating system' from 2002, application of pro-environmental elements has been extended. But the concept of substantial pro-environmental housing remains the stage of complex planning yet and application of system to interior space which has the most direct influence on actual dwellers is very poor.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.443-444
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• 2007

• 한국도로학회논문집
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• 제16권5호
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• pp.59-66
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• 2014

PURPOSES : This study is to predict the Sound Pressure Level(SPL) obtained from the Noble Close ProXimity(NCPX) method by using the Extended Kalman Filter Algorithm employing the taylor series and Linear Regression Analysis based on the least square method. The objective of utilizing EKF Algorithm is to consider stochastically the effect of error because the Regression analysis is not the method for the statical approach. METHODS : For measuring the friction noise between the surface and vehicle's tire, NCPX method was used. With NCPX method, SPL can be obtained using the frequency analysis such as Discrete Fourier Transform(DFT), Fast Fourier Transform(FFT) and Constant Percentage Bandwidth(CPB) Analysis. In this research, CPB analysis was only conducted for deriving A-weighted SPL from the sound power level in terms of frequencies. EKF Algorithm and Regression analysis were performed for estimating the SPL regarding the vehicle velocities. RESULTS : The study has shown that the results related to the coefficient of determination and RMSE from EKF Algorithm have been improved by comparing to Regression analysis. CONCLUSIONS : The more the vehicle is fast, the more the SPL must be high. But in the results of EKF Algorithm, SPLs are irregular. The reason of that is the EKF algorithm can be reflected by the error covariance from the measurements.

• Journal of Contemporary Eastern Asia
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• 제14권2호
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• pp.17-36
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• 2015

As an effort of mitigating hazards, pro-environmental programs have been vigorously activated with regard to solid waste recycling. It is beneficial for both the environment and resource saving, but implementation and enforcement are hard to achieve voluntarily. The South Korean Government first implemented the Deposit Refund System (DRS) and later the Extended Producer Responsibility Program (EPR) to reduce waste and encourage recycling in South Korea. Un-der the DRS, producers would pay for recycling the wastes of the products. The government then repealed the DRS and implemented the EPR program. Under this program, the producers recycle as much as the Ministry of Environment determines or pay a penalty for an excessive amount of the waste. In the broader perspective of disaster management, such policy programs can mitigate environmental hazards. This paper compares those two programs that facilitated the level of recycling, focusing on how such programs regulate producers and how they were operated from the perspective of implementation and enforcement.

• Journal of applied mathematics & informatics
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• 제6권2호
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• pp.393-406
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• 1999

Affine invariant sufficient conditions are given for two local convergence theorems involving inexact Newton-like methods. The first uses conditions on the first Frechet-derivative whereas the second theorem employs hypotheses on the second. Radius of con-vergence as well as rate of convergence results are derived. Results involving superlinear convergence and known to be true for inexact Newton methods are extended here. Moreover we show that under hypotheses on the second Frechet-derivation our radius of convergence results are derived. Results involving superlinear convergence and known to be true or inexact Newton methods are extended here. Moreover we show that under hypotheses on the second Frechet-derivative our radius of conver-gence is larger than the corresponding one in [10]. This allows a wider choice for the initial guess. A numerical example is also pro-vided to show that our radius of convergence is larger then the one in [10].

• 한국게임학회 논문지
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• 제10권4호
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• pp.23-34
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• 2010

`e-스포츠'에 대한 국가적인 관심증가는 경제적 효과와 동시에 사회적인 변화를 가져왔다. 또한 전문적으로 게임을 하는 집단인 '프로게이머'를 보유한 한국은 게임종주국으로서의 위상을 가지며 세계적인 관심 속에서 양적, 질적 성장을 거듭하고 있다. 이에 프로게이머를 사회적인 인적자원으로서 분류하고 체계적이고 이론적으로 정립할 필요성이 요구된다. 본 연구는 프로게이머들의 발달과 학습에 관한 이론적 모형을 제시하기 위하여 수행되었다. 모형은 수립은 근거이론 방법에 의한 자료분석에 의거하였다. 총 9명의 프로게이머 자료가 분석되었으며 3명의 전문가(감독, 컨설턴트)에 의해 모형 검증 및 수정의 단계를 거쳤다. 분석된 자료의 결과는 다음과 같다. 첫째, 프로게이머의 발달은 선형적 모형이 아닌 '단계(stage)'로 구분되는 형태를 나타낸다. 둘째, 'Enjoying', 'Struggling', 'Achieving', 'Slumping', 'Recovering'로 명명되어지는 각각의 단계는 학습방법과 동기적 측면, 교육과정, 동료와 상호작용 유형에 있어 고유한 속성을 가진다. 셋째, 기 명명된 5 단계는 유사한 속성에 따라 'Communicative Stage'와 'Practicing Stage'로 분류된다. Communicative Stage의 속성으로서 비구조화된 교육과정, 내재적 동기에 의한 학습형태, 수평적 관계에 의한 상호작용 형태가 나타났으며, Practicing Stage의 속성으로는 구조화된 교육과정, 외재적 동기에 의한 학습, 경쟁적, 수직적인 상호작용 유형이 나타났다. 이러한 결과는 Pedagogy와 Andragogy를 비교한 Knowles(1980)의 이론적 분류를 통하여 선수관리의 방향점을 제안한다. 즉, 게임 전문가 집단으로서 프로게이머의 관리는 첫째, 제시된 모형에 의거 선수들의 상황을 적절하게 분석하는 과정을 필요로 한다. 둘째, 분석된 발달단계에 따른 적합하고 구체적 관리방법이 적용되어야 한다. 셋째, 선수들의 단계이동을 도모하기 위해서는 지엽적 훈련과정보다는 모형에 입각한 총체적이고 체계적인 접근이 필요하다.

• Journal of Nutrition and Health
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• 제40권3호
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• pp.211-220
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• 2007

The purpose of this study was to investigate that the effect of dietary fatty acid composition on pro- and macro-glycogen utilization and resynthesis. The analyses were further extended for different muscle fibers (type I, type II, & type IIb) as well as tissues (i.e., liver & heart). Total one hundred sixty Sprague-Dawley rats were used, and rats were randomly allocated into four experimental groups: animals fed standard chow diet (n=40), animals fed saturated fatty acid diet (n=40), animals fed monounsaturated fatty acid (n=40), and animals fed polyunsaturated fatty acid (n=40). Animals in each groups were further divided into five subgroups: sacrificed at REST (n=8), sacrificed at immediately after 3 hr swim exercise (P-0HR, n=8), sacrificed at one hour after 3 hr swim exercise (P-1HR, n=8), sacrificed at four hour after 3 hr swim exercise (P-4HR, n=8), and sacrificed at twenty-four hour after 3 hr swim exercise (P-24HR, n=8). Soleus (type I), red gastrocnemius (type IIa), white gastrocnemius (type IIb), liver, and heart were dissected out at appropriated time point from all animals, and were used for analyses of pro- & macro-glycogen concentrations. After 8 weeks of dietary interventions, there was no significant difference in body mass in any of dietary conditions (p>.05). After 3 hr swim exercise, blood lactate level was higher compared to resting conditions in all groups, but it was returned to resting value after 1 hr rest (p<.05). Free fatty acid concentration was higher in all high fat fed groups(regardless of fatty acid composition) than CHOW consumed group. At rest, pro- & macro-glycogen concentration was not different from any of experimental groups (p>.05). Regardless of forms of glycogen, the highest level was observed in liver (p<.01), and most cases of supercompensation after 3hr exercise observed in this study were occurred in CHOW fed tissues. Except heart muscle, all tissues used in this study showed that pro- and macro-glycogen concentration was significantly decreased after 3 hr exercise. Based on these results, two conclusions were made: first, there is no different level of glycogen content in various tissues regardless of types of fatty acids consumed and second, the highest mobilization rate would be demonstrated from CHOW fed animals compare to animals that consumed any kinds of fatty acid diet if prolonged exercise is applied.

• Imaging Science in Dentistry
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• 제54권1호
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• pp.57-62
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• 2024

Purpose: This report presents a unique case featuring real, ghost, and pseudo-ghost images on the panoramic radiograph of a patient wearing earrings. It also explains the formation of these images in an easy-to-understand manner. Materials and Methods: One real image and two ghost images appeared on each side of a panoramic radiograph of a patient wearing earrings on both sides. Of the two ghost images on each side, one was considered a typical ghost image and the other was considered a ghost-like real image (pseudo-ghost image). The formation zones of the real, double, and ghost images were examined based on the path and angles of the X-ray beam from the Planmeca ProMax. To simulate the pseudo-ghost and typical ghost images on panoramic radiography, a radiopaque marker was affixed to the right mandibular condyle of a dry mandible, and the position of the mandible was adjusted accordingly. Results: The center of rotation of the Planmeca ProMax extended beyond the jaw area, and the area of double image formation also reached beyond the jaw. The radiopaque-marked mandibular condyle, situated in the outwardly extending area of double image formation, exhibited triple images consisting of real, double (pseudo-ghost), and ghost images. These findings helped to explain the image formation associated with the patient's earrings observed in the panoramic radiograph. Conclusion: Dentists must understand the characteristics and principles of the panoramic equipment they use and apply this understanding to taking and interpreting panoramic radiographs.

• Biomolecules & Therapeutics
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• 제32권4호
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• pp.481-491
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• 2024

Paxlovid is the first approved oral treatment for coronavirus disease 2019 and includes nirmatrelvir, a protease inhibitor targeting the main protease (M^pro) of SARS-CoV-2, as one of the key components. While some specific mutations emerged in M^pro were revealed to significantly reduce viral susceptibility to nirmatrelvir in vitro, there is no report regarding resistance to nirmatrelvir in patients and animal models for SARS-CoV-2 infection yet. We recently developed xenograft tumors derived from Calu-3 cells in immunodeficient mice and demonstrated extended replication of SARS-CoV-2 in the tumors. In this study, we investigated the effect of nirmatrelvir administration on SARS-CoV-2 replication. Treatment with nirmatrelvir after virus infection significantly reduced the replication of the parental SARS-CoV-2 and SARS-CoV-2 Omicron at 5 days post-infection (dpi). However, the virus titers were completely recovered at the time points of 15 and 30 dpi. The virus genomes in the tumors at 30 dpi were analyzed to investigate whether nirmatrelvir-resistant mutant viruses had emerged during the extended replication of SARS-CoV-2. Various mutations in several genes including ORF1ab, ORF3a, ORF7a, ORF7b, ORF8, and N occurred in the SARS-CoV-2 genome; however, no mutations were induced in the M^pro sequence by a single round of nirmatrelvir treatment, and none were observed even after two rounds of treatment. The parental SARS-CoV-2 and its sublineage isolates showed similar IC₅₀ values of nirmatrelvir in Vero E6 cells. Therefore, it is probable that inducing viral resistance to nirmatrelvir in vivo is challenging differently from in vitro passage.