The Design of a Quality of Experience Model for Providing High Quality Multimedia Services

Kwon, A.,Kang, J.-M.,Seo, S.-s.,Kim, S.-S.,Chung, J.Y.,Strassner, J.,Hong, J.W.-K. SPRINGER-VERLAG 2010 Lecture Notes in Computer Science Vol.6473 No.-

2015 개정 교육과정 물리학 II 교과서의 트랜지스터에 관한 내용 분석

이권아(Kwona Lee),석효준(Hyojun Seok),하상우(Sangwoo Ha) 한국물리학회 2022 새물리 Vol.72 No.5

본 연구에서는 2015 개정 교육과정의 물리학Ⅱ 교과서에 제시된 트랜지스터에 대한 내용이 성취기준에 도달할 수 있도록 구성되어 있는지 살펴보았다. 구체적으로 내용의 정확성, 학습자의 편의성, 삽화의 정확성 측면에서 트랜지스터의 구조, 트랜지스터의 증폭 원리, 바이어스 전압에 대한 내용을 분석하였다. 연구 결과, 성취 기준에 도달하기 위해 필수적으로 포함되어야 할 범용 dc 바이어스 회로의 설명이 부족하였고, 트랜지스터의 기본이 되는 pn접합의 설명이 누락되어 있었다. 또한 부정확한 용어와 불분명한 삽화가 다수 발견되었다. 이에 학생들이 교육 과정에 제시된 성취 기준에 도달할 수 있도록 여러 시사점들을 논의하였다.<br/> We analyzed the unit of transistors in all physics II textbooks of the 2015 revised curriculum to see if the contents are suitable for students to reach the standards suggested by the curriculum. Specifically, we investigated the description of the structure of a transistor, amplification in transistors, and transistor bias voltage in the textbooks in terms of description accuracy, the learner’s convenience, and illustration accuracy. We found that the explanation of the universal dc bias circuit is not enough that it is hard for students to choose a bias voltage using resistors in a transistor circuit as an amplifier. There is no description of the basic elements to understand how transistors work, such as the pn junction of semiconductors. In addition, it was found that there is a lack of explanation of the essential contents, and many inaccurate terms and vague illustrations. We discussed several implications of this study.<br/>

Structural and electrical properties of Ba(Sr,Ti)O3/ K(Ta,Nb)O3 multilayer thin film for the application of electro-caloric devices

Min-Su Kwona,Sung-Gap Lee,Kyeong-Min Kim,Seungkeun Choi 한양대학교 세라믹연구소 2019 Journal of Ceramic Processing Research Vol.20 No.6

In this study, the multilayered thin films of (Ba,Sr)TiO3/K(Ta,Nb)O3 were fabricated by the sol-gel and spin coating methods, and their structural and electrical properties were investigated. The specimen showed polycrystalline X-ray diffraction (XRD) characteristics with a tetragonal structure. The average grain size and film thickness for one coating were about 30~40nm and 60nm, respectively. The phase transition temperature of specimen was lower than 10 oC. The dielectric constant and loss at 20 oC of the specimen coated six times were 1,231 and 0.69, respectively. The rate of change in dielectric constant at an applied direct current (DC) voltage of the six times coated thin films was 17.3%/V. The electrocaloric effect was the highest around the temperature at which the remanent polarization rapidly changed. When an electric field of 660kV/cm was applied to the triply coated thin films, the highest electrocaloric property of 4.41 oC was observed.

스튜어드십 코드 채택이 ESG 등급에 미치는 영향: 국민연금 사례를 중심으로

권지원 ( Jiwon Kwona ),최우석 ( Wooseok Choib ) 한국회계학회 2024 회계저널 Vol.33 No.1

본 연구의 목적은 2018년 국민연금의 스튜어드십 코드 채택이 피투자회사의 ESG 등급에 미치는 영향을 실증적으로 분석하는데 있다. 또한 국민연금이 스튜어드십 코드를 채택한 이후 반대의결권 행사가 피투자회사의 ESG등급 개선에 실질적인 영향을 미쳤는지에 대해서도 분석한다. 실증분석 결과, 국민연금이 스튜어드십 코드를 채택한 이후, 피투자회사의 환경관련 등급이외의, 사회관련 등급 및 지배구조관련 등급이 모두 개선되었다. 또한 국민연금의 반대의결권 행사가 피투자회사의 ESG등급 개선에 실질적인 영향을 미치는 것으로 나타났다. 구체적으로 사회관련 등급과 지배구조관련 등급이 반대의결권 행사의 영향을 받아 개선되는 것으로 나타났다. 이와 같은 결과는 국민연금의 스튜어드십 코드 채택이 피투자회사의 ESG등급 개선에 기여하였고, 반대투표 등의 적극적 주주권 행사는 ESG등급 개선에 도움이 될 수 있음을 시사한다. 본 연구의 공헌점은 스튜어드십 코드의 제도적 도입 효과를 실증적으로 검증하고 국민연금의 기금운영 정책에 시사점을 제공하였다는데 있다. 구체적으로 본 연구에서는 스튜어드십 코드 도입이 기관투자자가 의결권 참여에 의한 적극적 주주권을 행사할 수 있는 길을 열어줌으로써, 피투자회사의 기업가치를 제고할 수 있는 수단을 제공해줄 수 있음을 보였다. 본 연구의 결과가 향후 국민연금을 포함한 기관투자자들의 기금운영 정책과 기업의 ESG 경영 전략에 실무적 시사점을 제공해줄 수 있을 것이라 기대된다. The purpose of this study is to verify whether the adoption of the stewardship code of the National Pension Service in 2018 had a positive effect on the ESG improvement of investee companies. We also analyze the relationship between corporate ESG ratings and the NPS’s negative voting. Specifically, it analyzes whether ESG ratings are being used as indicators of negative voting, and also analyzes whether the exercise of negative voting rights by the National Pension Service has a substantial impact on the improvement of the ESG ratings of investee companies. As a result of the empirical analysis, after the National Pension Service adopted the stewardship code, the environment-related, social-related, and governance-related ratings of investee companies are all improved. In addition, we find that the exercise of its negative voting right has a substantial impact on the improvement of the social (S) and governance (G) ratings of the investee company. These results show that the adoption of the stewardship code by the National Pension Service has improved the ESG of investee companies, and that the exercise of shareholder rights such as negative voting is the motivation for ESG improvement.

기어 정밀도를 고려한 e-PGS 피니언의 굽힘 강도설계

권순만(Soon-man Kwona) 한국생산제조학회 2021 한국생산제조학회지 Vol.30 No.6

Bioequivalence Comparison of Two Formulations of Fixed-Dose Combination Glimepiride/Metformin (2/500 mg)Tablets in Healthy Volunteers

Jung, Sang-hoon,Chae, Jung-woo,Song, Byung-jeong,Kwona, Kwang-il Shaheed Beheshti University of Medical Sciences 2014 Iranian journal of pharmaceutical research Vol.13 No.2

<P>Glimepiride/metformin (2/500 mg) is an oral antihyperglycemic agent for the treatment of type 2 diabetes. A generic glimepiride/metformin (2/500 mg) fixed-dose combination (FDC) tablet was developed recently. This study was designed to collect data for submission to Korean regulatory authorities to allow the marketing of the test formulation. We evaluated the comparative bioavailability and tolerability of the test and reference formulations in healthy male adult volunteers. This single-dose, randomized, double-blind, two-way crossover trial was conducted at Bestian Medical Center in Bucheon, Korea. In total, 40 male Korean volunteers were enrolled. The subjects were randomized to receive an FDC tablet containing the glimepiride/metformin (2/500 mg) test or reference formulation, and pharmacokinetic(PK) parameters were measured. After a 1-week washout period, the other formulation was administered and the PK parameters were measured again. The C<SUB>max </SUB>and AUC<SUB>t </SUB>were determined from blood samples obtained at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 12, and 24 h after drug administration. Bioequivalence was considered established if the 90% CIs of the geometric mean ratios(GMRs) of the test-to-reference formulations for C<SUB>max </SUB>and AUC<SUB>t </SUB>were within the predetermined regulatory range of 80-125%. In total, 40 healthy male subjects were enrolled and completed the study (mean [SD] age, 23.2[2.26]years[range, 19-30years];weight, 68.95[8.30]Kg[range, 52.0-87.0 Kg]; and height, 175.4[5.34] cm[range, 164-189 cm]). The GMRs(90% CI) of the glimepiride C<SUB>max </SUB>and AUC<SUB>t </SUB>were 1.006(0.947-1.069) and 1.010(0.953-1.071), respectively. For metformin, the values were 1.019(0.959-1.083) and 1.035(0.989-1.084), respectively. The test and reference formulations had similar PK parameters. The test formulation of glimepiride/metformin (2/500 mg) FDC tablets met the Korean regulatory criteria for bioequivalence. </P>

The reliability of an easy measuring method for abutment convergence angle with a computer-aided design (CAD) system

Jai-Bong Lee,Sung-Hun Kim,In-Sung Yeo,Jung-Suk Han,Taek-Ka Kwona,Yong-Joon Seoa 대한치과보철학회 2014 The Journal of Advanced Prosthodontics Vol.6 No.3

PURPOSE The purpose of this study was to evaluate the intra-rater reliability and inter-rater reliability of three different methods using a drawing protractor, a digital protractor after tracing, and a CAD system. MATERIALS AND METHODS Twenty-four artificial abutments that had been prepared by dental students were used in this study. Three dental students measured the convergence angles by each method three times. Bland-Altman plots were applied to examine the overall reliability by comparing the traditional tracing method with a new method using the CAD system. Intraclass Correlation Coefficients (ICC) evaluated intra-rater reliability and inter-rater reliability. RESULTS All three methods exhibited high intra-rater and inter-rater reliability (ICC>0.80, P<.05). Measurements with the CAD system showed the highest intra-rater reliability. In addition, it showed improved inter-rater reliability compared with the traditional tracing methods. CONCLUSION Based on the results of this study, the CAD system may be an easy and reliable tool for measuring the abutment convergence angle.