강결합방식의 GPS/INS 시스템에 대한 측정치 시간지연 추정 연구

이윤선,이상정,Lee, Youn-Seon,Lee, Sang-Jeong 한국군사과학기술학회 2008 한국군사과학기술학회지 Vol.11 No.4

In this paper we study the performance of the measurement time-delay estimation of tightly-coupled GPS/INS(Global positioning system/Inertial Navigation system) system. Generally, the heading error estimation performance of loosely-coupled GPS/INS system using GPS's Navigation Solution is poor. In the case of tightly-coupled GPS/INS system using pseudo-range and pseudo-range rate, the heading error estimation performance is better. However, the time-delay error on the measurement(pseudo-range rate) make the heading error estimation performance degraded. So that, we propose the time-delay model on the measurement and compose the time-delay estimator. And we confirm that the heading error estimation performance in the case of measurement time-delay existence is similar with the case of no-delay by Monte-Carlo simulation.

하악 전돌증 환자에서 악교정 수술방법에 따른 설골과 혀의 위치 및 기도량 변화의 비교

이윤선,한세진,Lee, Yoon-Sun,Han, Se-Jin 대한악안면성형재건외과학회 2013 Maxillofacial Plastic Reconstructive Surgery Vol.35 No.4

Purpose: The purpose of this study was to compare the changes in the pharyngeal airway space, tongue and hyoid bone positions according to the orthognathic surgical methods of mandibular prognathism. Methods: The subjects included 30 patients (16 males, 14 females) with the skeletal class III malocclusion. Group 1 (10 patients) underwent bilateral sagittal split ramus osteotomy (BSSRO) only; group 2 (10 patients) underwent BSSRO with genioplasty; and group 3 (10 patients) underwent BSSRO, Le Fort I osteotomy. We measured the lines between the selected upper air way, hyoid bone and tongue landmarks on the lateral cephalometric x-ray films of skeletal class III. The measurements were made preoperation, within 1 week after the operation, 3~6 months after the operation and 1 year after the operation. We compared and analyzed the measurements with matched paired t-test and independent samples t-test. Results: There were no postoperative changes in the nasopharyngeal airway space in group 3. The measurements of group 3 also increased during the follow-up period as compared to the preoperative measurements. In group 1, 2 and 3, the immediate postoperative oropharyngeal and hypopharyngeal airway spaces were decreased. In the following period, the hypopharyngeal airway space returned to the preoperative positions, but the oropharyngeal airway space was not significantly changed. The upper and lower tongue was posteriorly repositioned immediately after the surgery. During the follow-up period, the lower tongue position returned to the preoperative position, and the upper tongue position was not significantly changed. Immediately after the surgery, the B point was moved to the posterior position, and a slight anterior advancement was found in the follow-up period. Conclusion: Patients who received the mandibular setback surgery showed a decrease in the posterior airway space, and those who underwent maxillary advancement showed a significant increase of the nasopharyngeal airway space, which remained stable during the evaluation period. The change of the airway space, position of the hyoid bone and tongue did not differ according to the presence or absence of genioplasty.

외란을 고려한 스트랩다운 관성항법장치 자이로 바이어스 교정기법

이윤선,이상정,Lee, Youn-Seon,Lee, Sang-Jeong 한국군사과학기술학회 2009 한국군사과학기술학회지 Vol.12 No.3

In this paper we study the gyro bias calibration method of SDINS(Strap-Down Inertial Navigation System). Generally, SDINS's calibration is performed in 2-axis(or 3-axis) rate table with chamber for varying ambient temperature. We assumed that the majority of calibration-parameter except for gyro bias is knowned. During gyrobias calibration procedure, it can be induced some disturbances(accelerometer's short-term error induced rate table rotation and anti-vibration mount's rotation). In these cases, old gyro-bias calibration methods(using velocity error or attitude error) have an error, because these disturbances are not detectable at the same time. So that, we propose a new gyro-bias calibration method(heading error minimizing using equivalent linear transformation) that can detect anti-vibration mount's rotation. And we confirm efficiency of the new gyro-bias calibration method by simulation.

우리나라 주식수익률(株式收益率)의 변동성(變動性)과 정보비대칭(情報非對稱)에 관한 실증적(實證的) 연구(硏究) - ARCH형태(形態)의 모형(模型)을 중심(中心)으로 -

이윤선,Lee, Yun-Seon 한국재무관리학회 1996 財務管理論叢 Vol.3 No.2

본 연구는 한국증권시장에서 변동성의 정보비대칭효과를 조건부 이분산모형을 이용하여 검증하고자 하였다. 검증방법으로는 Engle과 Ng (1993)의 연구에 기초하여 정보반응곡선(News impact curve)으로 분석하였다. 분석자료로 1980년 부터 1995년 까지의 한국종합주가지수, 일별 초과수익률자료를 사용하였다. 정보반응곡선에 이용한 모형은 GARCH 모형, EGARCH 모형, TGARCH 모형, AGARCH 모형등 4개의 조건부 이분산 모형이다. 무조건 분산을 이용한 정보 반응곡선의 함수형태로 보면, 분산의 정보반응에 있어서 GARCH 모형은 대칭적으로 반응하며 나머지 조건부 이분산 모형인 EGARCH 모형, TGARCH 모형, 그리고 AGARCH 모형은 비대칭적으로 반응하는 모형임을 알 수 있었다. 실증분석결과 정보반응곡선을 통하여 악재(bad news)정보에 따라 예측하지 못한 주식수익률의 하락이 호재(good news)에 따른 예측하지 못한 주식수익률의 상승보다 더 큰 변동성을 발견할 수 있었다. 그러나 비대칭성의 크기는 그다지 큰 것으로 보이지 않았다. 모형적합성 검정에서도 4개의 조건부 이분산 모형은 모두 적합한 것으로 보인다. 그중에서도 EGARCH 모형과 TGARCH 모형이 상대적으로 주가예측력이 뛰어나 보인다. 그러나 변동성의 정보 비대칭반응을 통계적으로 유의적인 것으로 확인한 모형은 TGARCH모형 뿐이었다.

비모수 분석방법에 의한 국내 건설조직 성과 측정 방향에 관한 연구 - DEA를 이용한 국내 연구 문헌 고찰을 기반으로 -

이윤선,Lee, Yoon-Sun 한국건설관리학회 2014 한국건설관리학회 논문집 Vol.15 No.5

자료포락분석모형은 다수의 산출을 생성하기 위해 다수의 투입을 사용하는 생산시스템의 상대적 효율성을 평가하는 비모수적 방법으로 건설생산체계의 복잡하고 동적인 특성을 반영할 수 있는 유용한 성과측정도구로 활용되고 있다. 본 연구는 DEA 방법론을 적용한 건설 생산조직의 성과측정 문헌들을 체계적으로 분석하고, 주요 이슈들과 향후 연구과제를 도출하였다. 국내외 선행 연구를 분석하여 성과 측정 목표 및 대상, 자료 구조화 방법, 생산가능집합과 효율성 척도 선정, 벤치마킹 및 사후 검증 등의 일련의 단계로 이루어진 성과측정체계를 제안하고, 1997년부터 2013년까지 DEA를 적용하여 국내 건설산업 성과측정 연구를 수행한 21편의 학술지를 분석하였다. 관찰된 주요 특성 및 결과들은 건설기업이 자신의 상대적 효율성 수준을 진단하고, 개선 방향을 제시하고, 향후 예측을 하는데 DEA방법론이 유용하게 적용되어왔다고 나타났다. 그러나 타산업의 연구와 비교해볼 때 국내 건설산업의 효율성 측정은 제한적으로 적용되고 있었다. 본 연구는 연구대상, 자료의 구조화, 측정모형, 모형 검증 등에 대한 개선방향을 제시함으로써 향후 DEA을 적용한 건설산업의 생산성 제고를 위한 연구 체계를 수립하는데 활용할 수 있을 것이다. Data envelopment analysis (DEA) measures the relative efficiency of decision making units (DMUs) with multiple performance factors that are grouped into outputs and inputs. DEA has proven to be superior to simple aggregation of performance measures, and is also useful for evaluating the performance of construction companies for comparison with competitor performance. The purpose of this study was to survey literatures on the application of DEA methodology and to propose a methodological scheme to measure the performance of construction organizations. Articles on previous studies were surveyed and examined as part of a comprehensive review. The survey revealed that the application of DEA in the construction industry was li mited. Further, the survey indicated that there is a need for the development of a methodological framework on the special goals and subjects of performance measurement, methods of data structure and collection, selection of appropriate DEA models, analysis of results, and post-test. Based on the survey, this study identified and discussed the types of major issues and topics for future studies from a methodological perspective, which could be helpful to researchers interested in using DEA to study performance issues in construction organizations.

인터넷 자원의 효율적 이용을 위한 가격결정 방법

이윤선,윤민영,Lee, Yun-Seon,Yun, Min-Yeong 한국정보처리학회 1999 정보처리학회논문지 Vol.6 No.11

Modeling for the Internet resource is important to use of limited resource efficiently. Also, the modeling could guide how we can approach the Internet problems. The many studies of price mechanism to internalize the externality, to decrease the externality from congestion, and to use the Internet resource efficiently, are widely going on. The represent styles for Internet pricing are usage-based pricing(UBP) and flat-rat pricing(FRP) and the FRP could prefers for the beginning stage of Internet introduce. The purpose of this study is to examine the efficiency of Internet pricing mechanism based on flat-rate pricing, both consumer and producer side.

기후변화 위기에 대응하는 건설기업 ESG 활동 및 성과 사례

이윤선,문혁,이태식,Lee, Yoonsun,Moon, Hyuk,Lee, Tai Sik 한국건설관리학회 2021 한국건설관리학회 논문집 Vol.22 No.2

지구 환경문제가 국제적인 문제로 부상하면서 국제사회는 글로벌 이슈(기후 변화, 빈곤퇴치, 인권 등)를 해결하기 위해 지속가능발전이라는 새로운 패러다임을 제시하며, 17개의 지속가능발전목표(SDGs)를 실행하고자 다양한 조직적 노력을 시도하며 통합해오고 있다. 최근 파리기후협정과 SDGs 달성에 필요한 재원을 마련하고자 지속가능한 금융의 투자가 확대되며 비재무적 요소인 환경·사회·지배구조가 기업의 미래 경쟁우위와 수익성을 결정하는 중요한 무형자산이 되어, 국내외 기관 투자자와 자산운용사들은 ESG 성과를 기반으로 투자를 확대하고 있다. 본 연구의 목적은 기업의 사회적 책임활동과 ESG 성과 정보 공개를 요구하는 국제적 기준과 이니셔티브를 도출하고, 건설기업의 ESG 활동 및 성과 수준을 분석하고자 한다. 본 연구의 결과는 향후 건설산업이 코로사19 사태, 탄소 중립, 중대 재해 발생 등으로 당면한 위기를 극복할 수 있도록 ESG 생태계를 구축하고, 무형자산 측정 및 관리를 위한 플랫폼 개발의 기본 자료로 활용되어 녹색 금융이 주는 비지니스 기회와 일자리 창출 등 사회적 가치 실현에 기여할 수 있을 것이다. Global governments and initiatives have attempted and integrated various organizational efforts to implement the 17 Sustainable Development Goals (SDGs), presenting a new paradigm of sustainable development to address global issues (climate change, poverty eradication, and human rights). Recently, investment in sustainable finance has expanded to finance the attainment of goals set out in the Paris Agreement and SDGs. Non-financial factors such as environment, social responsibility, and governance (ESG) have become intangible assets that determine the future competitiveness and profitability of companies. Domestic and foreign institutional investors and asset management companies have been expanding their investments based on the ESG performance of companies. In this study, we aim to derive international standards and initiatives that require disclosure of information on corporate social responsibility activities and ESG performance and analyze construction companies' ESG activities and performance levels. The results of this study can be used as the basis to develop platforms for the construction industry ESG ecosystem and the measurement and management of intangible assets. These could ultimately contribute to overcoming the crisis in the future due to the outbreak of the COVID-19 pandemic, fostering net-zero emissions, and preventing fatal workplace accidents in the construction industry.

여수 영당의 역사와 지속가능한 민속경관 전략

이윤선 ( Yoon Sun Lee ) 남도민속학회 2007 남도민속연구 Vol.14 No.-

This study is preceeded with two purposes; one is to exam the present situation of Yeosoo shrine by its history and culture and to inquire into its humanistic foundation, and the other is to inquire into a strategic plan on the sustainable possibility of the exorcism for a big catch of fish of shrines in the side of the preservation and the utilization of a local culture prototype. For these purposes, the study exams the meaning of a city of scenary to the side of a folk of scenary where ‘place’ and ‘folk play’ are performed. Yeosoo shrine has known for the only shrine for the sea god to deify General Lee Soon-shin. Supposed that the shrine was built in 1443, the history of the shrine can be gone back to 15th century or more over. It is said that the shrine was originally for deifying General Choi Young. After going through various processes, the shrine changed the present shrine to deify both General Lee and Choi. According to the related record, there was a portrait scroll centering around General Lee in the record of the shrine until 1942 including the record in 1900. Besides the study can confirm that the tablet was moved into this place. However the portrait was forced removal by Japanese Imperialism on 1943, and having been entirely abolished by the reclamation to establish the Far East Fishing Port Base, the portrait was restored on 1982. The shrine can be said as the representative popular religious place of Yeosoo to take pride in a long history and tradition. Accordingly, the study considers that the shrine can function as the supplementary and complementary system of folk scenary to be able to offset the image of Yeosoo like a fishery city in Japanese Imperialism and a city of chemical industry. This is because the study considers this fact as one of repositioning work and also considers it as a scenary that can complement Yeosoo′s scenary covered with a modern inharmony. In Korean traditional thought of configuration of the ground, a complementary divination by configuration of the ground is a humane countermeasure to have a purpose on the achievement of constancy and stability in the ecological atmosphere of a dwelling site by the harmony of divination by configuration of the ground when the atmosphere is lack. Therefore, the study concludes the shrine can be preserved and utilized continuously in that the shrine has the modern meaning of folk scenary which complement a scenary of city as well as has a long history and tradition. The designation as cultural properties can be the most realistic plan for its preservation. The designation, as UNESCO has pointed it a long time ago, can be interpreted as a cultural scenary or humane scenary. Supposed the side of a designation as cultural properties, it will be possible of designation in the part of “Modern Cultural Heritage”, “Data of Cultural Properties”, “Monument”, and “Folk Data”. Among them, the designation as Folk Data will be the most realistic plan. This is because the study estimates that the supplementary and complementary tradition culture scenary by the designation can function as a port scenary system in the city scenary of Yeosoo.

안 부속기 림프구증식성 질환의 예후

이윤선 ( Yun Sun Lee ),이무일 ( Moo Ill Lee ),박태성 ( Tae Sung Park ),이상렬 ( Sang Yeul Lee ) 대한안과학회 2003 대한안과학회지 Vol.44 No.6

원자로압력용기용 SA508 Gr.4N Ni-Mo-Cr계 저합금강 용접열영향부의 용접후열처리에 따른 미세조직과 기계적 특성 평가

이윤선 ( Yoon Sun Lee ),김민철 ( Min Chul Kim ),이봉상 ( Bong Sang Lee ),이창희 ( Chang Hee Lee ) 대한금속재료학회 2009 대한금속·재료학회지 Vol.47 No.3