미세조류와 방사선 세슘, 스트론튬, 우라늄의 반응 특성

이승엽,이지영,이재광,정광환,이승엽,정종태,김경수 한국방사성폐기물학회 2013 한국방사성폐기물학회 학술논문요약집 Vol.11 No.2

A study on the prevalence of the idiopathic osteosclerosis in Korean malocclusion patients

이승엽,박인우,장인산,최동순,차봉근,Lee, Seung-Youp,Park, In-Woo,Jang, In-San,Choi, Dong-Soon,Cha, Bong-Kuen Korean Academy of Oral and Maxillofacial Radiology 2010 Imaging Science in Dentistry Vol.40 No.4

Purpose : This retrospective study was performed to investigate the prevalence of the idiopathic osteosclerosis (IO) in Korean malocclusion patients according to age, sex, and the Angle's classification of malocclusion. Materials and Methods : This study consisted of 2,001 randomly selected patients from the Department of Orthodontics at the Gangneung-Wonju National University Dental Hospital, Korea. The prevalence of IO in Korean malocclusion patients was recorded using their panoramic radiographs, and the following parameters were surveyed; age, sex, and the Angle's classification of malocclusion. The chi-square test was analyzed to determine the statistical significance of differences in the prevalence of IO between age, sex, and the Angle's classification of malocclusion. Results : The prevalence of IO in the jaws was 6.7% in a total of 2,001 examined orthodontic patients. The majority of IO was found in the mandible (96.58%). The 30-39 age group showed the highest prevalence of IO (9.60%). There was a higher prevalence in females (6.89%) than in males (6.45%). The prevalence of IO in Angle Class I group (7.07%) was the most frequent, followed by Angle Class II group (6.72%), and Angle Class III group (6.40%). However, there was no statistical significance in sex and Angle's classification of malocclusion. Conclusion : The prevalence of IO in malocclusion patients showed the differences between various age groups and most of them were found in the mandibular posterior area. However, sex and the type of malocclusion are not to be considered as a contributing factor of IO.

자동차부품 수출기업의 경쟁력 결정요인에 관한 연구

이승엽,정경애,구자열 한국경영교육학회 1999 경영교육연구 Vol.17 No.-

마이크로스트립 선로의 트랜지션을 위한 비아(via) 해석 및 설계

이승엽 여수대학교 산업기술지역개발연구소 2000 産業基術硏究所 論文集 Vol.9 No.-

The miniaturization and ever higher density packing of electronic devices is driving a trend toward three-dimensional, multilayer circuits. At the same time, the clock rates in digital devices and the operating frequencies in communication systems aue steadily increasing. In multiiayer circuits, signals are carried between the layers through via. Therefore, this paper reports the propagation characteristics of a via. Especially, the effects of rod diameter and clearance hole size. are examined. There is a wide range of sizes of via in multilayer circuits, so the sizes of via in this paper were selected for ease anaccuracy of measurements. The obtained results showed that at high frequencies, radiation is at a significant level and the frequency characteristics of radiation depend on the structure of the via

하드디스크 및 광 디스크 드라이브의 개발 동향과 기계적 진동의 영향

이승엽 한국소음진동공학회 1998 소음 진동 Vol.8 No.5

글로벌 서비스산업의 비용구조와 규모의 경제/기업의 생존성과 장기평균비용곡선의 분석 : run Average Cost

이승엽,권업 韓獨經商學會 1998 經商論叢 Vol.16 No.2

The authors provide an initial investigation of the cost structure of global service industries, using Stigler's (1958) survivor technique and the authors' cross-sectional LAC (Long-run Average Cost) analysis method. (1) In consistence with previous research, the test shows that service industries have been less efficient than manufacturing industries in terms of economies of scale. Service industries1拉ye been featured Stigler's (1958) saucer-type or traditional U-shape LAC, while manufacturing industries have inverse-J type. Although the results were inferred to affected particularly by samples of manufacturing industries (i.e., energy and electronic components), we believe that the trend might approximately reflect the reality. (2) In addition, equipment-based (i.e., telecommunication) and people-based service .e., business service) industries were compared in terms of scale effects. As expected, equipment-based service industries (Bain's L-shape) were higher in costefficiency than people-based service industries (U-shape). An additional ROA (Return on Assets) analysis supports the results of both investigations. We believe that the results were not cohort-specific because all of company samples of this research operate globally

논문 : 지구환경과 교육 ; 한반도 동남부 제3기분지에 발달하는 단층비지대의 미구조 및 지구화학적 특성

이승엽,장태우 한국지구과학회 2004 지구과학 교육심포지엄 및 춘계학술발표회 Vol.2004 No.-

마아케팅情報시스템에 關한 硏究

李承燁 啓明大學校 産業經營硏究所 1985 經營經濟 Vol.18 No.1

The focus of this research is upon marketing information systems. For purpose of this study, MKIS is recognized as the mechanism by which firms gather business data for use in marketing decision making. This research is devoted to an examination of the use of MKIS in business firms of the advanced nations. More specifically, the objectives of this research are to: 1) construct theoretical framework for MKIS; 2) delineate the present uses of MKIS in business firms of the advanced nations (US and UK); 3) discuss main problems and possible solutions concerning to the effective design and uses of MKIS. These objectives are accomplished by analyzing over one hundred theoretical or empirical articles regarding to MKIS. Findings from the observations indicate that marketers have not lost the enthusiasm for the M(K)IS concept evidenced by the theoreticians of the the 1960s and early-1970s. Those normative designs, for the most part, have been implemented. And improvements beyond the dreams of the early visionaries have been achieved due to the availability of better hardware and software and, most importantly, an increasing level of computer and M(K)IS literacy among marketing managers. Other findings indicate that marketers who are interested in designing and using the effective MKIS must consider such problems inherent in operational MKIS development as the location of MKIS within the organization, the human side of MKIS, the internal marketing problem-selling the MKIS as designed to the system user, and the determination of the managers' information needs. In conclusion, the research findings could be used as a basis for marking suggestions regarding marketing information activities of our business firms, and naturally a great deal of further research is needed in this area.

스펙트럼 영역에서의 마이크로스트립-슬롯 결합 선로 해석

이승엽,박한규 한국통신학회 1994 韓國通信學會論文誌 Vol.19 No.3

본 논문에서는 마이크로스트립-슬롯 결합 선로에 대한 Green함수를 스펙트럼 영역에서 유도하고, 수치적 결과를 정확히 얻기 위해 마이크로스트림 선로와 슬롯 부분에서의 전류분호에 대한 특이점을 고려한 기저함수를 이용한 Galerkin방법을 적용하여 선로의 특성 파라미터를 계산하였다. 특히, 마이크로스트림-슬롯 결합선로의 특성 중 마이크로스트립 선로에의한 우모드(even mode)와 슬롯에 의한 기모드(odd mode)의 특성에 의한 선로의 각 특성을 구하였고, 계산 결과값의 정확성을 비교하기 위해 기존의 데이터와 비교하였다. A coupled microstrip-slot line is analyzed using a full wave method in the specral domain. The characteristics of the coupled microstrip-slot line are obtained based on the Galerkin`s method. The characteristics of even mode by microstrip line and odd mode by slot line are calculated respectively. Especially the singularity of basis function is enforced to be considered with respect of modes. Numerical results are compared with available data and shown good agreement.

Wire-Grid 방법을 이용한 도체 상자에 부착된 선형 모노폴 안테나 해석

이승엽,김경재,이영훈,허선종,박한규 한국통신학회 1993 韓國通信學會論文誌 Vol.18 No.11

본 논문에서는 도체 상자에 부착된 선형 모노폴(thin-straight monopole) 안테나를 wire-grid방법을 적용하여 안테나 및 도체상자를 모델링하였고, 효율적인 계산을 위해 Pocklington 적분 방정식과 모멘트 방법(Moment Method)을 사용하여, 안테나의 특성 변화를 계산하였다. 안테나 및 모델링된 도체상자에 이용된 기저함수는 PWS(Piecewise Sinusoidal)함수이고, 도체상자의 모서리에 흐르는 전류를 효과적으로 표현하기 위해, 접합기저함수(Junction Basis Function)를 사용하였다. 특히, 모서리의 꼭지점에서 전류의 연속 조건을 만족하기 위해, 접합기저 함수가 중복되도록 하였다. 안테나 및 도체상자에 흐르는 전류분포를 계산하여, 입력 임피던스 및 복사패턴을 구하였고, 기존의 결과 데이터와 비교하였다. In this paper, a thin-straight monopole antenna attached to a conducting box is analyzed using a moment method with the pocklington integral expression for the exact Green's function. A modeling of a conducting box is based on a Wire-Grid method for an efficient calculation procedure. A system of linear equation is obtained using the piecewise sinusoidal basis function. And a Junction basis function is enforcing to represent the physical current on the edge of the conducting box. Especially, the junction basis functions are overlapped for the current continuity preserving on the vertexes. Numerical results are obtained for the current distribution on the unified antenna/conducting box system, input impedance and radiation pattern. The results are compared with the known data.