http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
자율주행 경로 추종 성능 개선을 위한 차량 조향 시스템 특성 분석
김창희,이동필,이경수,Kim, Changhee,Lee, Dongpil,Yi, Kyongsu 한국자동차안전학회 2020 자동차안전학회지 Vol.12 No.2
This paper presents steering system requirements to ensure the stabilized lateral control of autonomous driving vehicles. The two main objectives of a lateral controller in autonomous vehicles are maintenance of vehicle stability and tracking of the desired path. Even if the desired steering angle is immediately determined by the upper level controller, the overall controller performance is greatly influenced by the specification of steering system actuators. Since one of the major inescapable traits that affects controller performance is the time delay of the steering actuator, our work is mainly focused on finding adequate parameters of high level control algorithm to compensate these response characteristics and guarantee vehicle stability. Actual vehicle steering angle response was obtained with Electric Power Steering (EPS) actuator test subject to various longitudinal velocity. Steering input and output response analysis was performed via MATLAB system identification toolbox. The use of system identification is advantageous since the transfer function of the system is conveniently obtained compared with methods that require actual mathematical modeling of the system. Simulation results of full vehicle model suggest that the obtained tuning parameter yields reduced oscillation and lateral error compared with other cases, thus enhancing path tracking performance.
김창희,임병묵,박해모,정명수,황귀서,신용철,고성규,장보형,이해웅,이영준,신헌태,박선주,현민경,이상재,Kim, Changhee,Lim, Byungmook,Park, Haemo,Jung, Myungsu,Hwang, Guiseo,Shin, Yongchul,Go, Sunggyu,Jang, Bohyung,Lee, Haewoong,Lee, Youngjun,Shin, 대한예방한의학회 2015 대한예방한의학회지 Vol.19 No.1
Objective : This study aimed to develop a new category system of Yanseng(養生) for traditional Korean Medicine in order to prepare the ground for organizing the resources of Yangseng systematically. Method : We reviewed the existing medical books containing Yangseng contents. Based on the experts' consensus, we drew the new category system of Yangseng in consideration of a national trait of Korea and use of Yanseng in modern society. Results : First, We devided Yangseng category into two parts: methods and applications. Methods are divided into 5 parts: mind, diet, herb, Doinangyo(導引按蹻), life. A broad use of herbs in daily life is a national trait of Korea. Doinangyo contains relaxation methods like breathing, massages and exercises like Qigong and is also very popular way to maintain health in modern western society. Applications are divided into 6 parts: type of constitution, life cycle, seasons, type of symptoms and signs, type of Mibyung(未病) and diseases. We drew this 6 parts in consideration of use in the field of health care. Conclusion : The new category system of yangseng is based on existing theories and reflects Korean national trait and use of Yanseng in modern society. We hope this new category system play a role of foundation for organizing the resources of Yangseng systematically.
해외 직구 및 역직구 수요 증가에 따른 물류 및 유통 기업 대응 방안 수립을 위한 효율성 분석 연구
김창희(Changhee Kim),양홍석(Hongsuk Yang),정재훈(Jaehoon Jung) 한국경영과학회 2017 한국경영과학회지 Vol.42 No.4
Today, E-Commerce is expanding rapidly and is becoming increasingly global. In this research, we analyzed fundamentals and the performance of E-Commerce companies to find ways to optimize operational efficiency for distribution corporations in Korea. The analysis focuses on international markets, including Amazon, Ebay, Williams-Sonomia Inc., Liberty Interactive Corp., Zalando, Home Retail Group, Groupe Casino, Alibaba, JD.com, Vipshop Holdings Ltd., Rakuten, Kakaku.com, and Yahoo-Japan. The research applied bootstrap-DEA analysis, non-parametric test, and Tobit regression on data extracted from 13 E-Commerce companies from 2012 to 2014. This research examines the management and export efficiencies of various companies, thus providing positioning details for Korean companies that specialize in distribution.
김창희(Kim Changhee) 한국법학원 2013 저스티스 Vol.- No.137
주가연계증권은 특정 주식 혹은 주가지수를 기초자산으로 하여 그 기초자산의 가격변동과 연계하여 미리 정해진 방법으로 상환금액이 결정되는 파생결합증권의 일종이다. 이 증권을 매입한 투자자는 상환금액이 결정되는 날 기초자산가격이 행사가 이상이 되면 원금에 높은 수익금을 가산하여 받을 수 있다. 반면 평가일에 기초자산가격이 행사가에 미치지 못할 경우 원금 이하의 금액을 받게 된다. 발행자는 투자자와 반대의 이해관계를 가진다. 2009년 이후 주가연계증권의 상환평가일에 발행자가 보유 중이던 기초자산을 대량매각하여 기초자산 가격을 행사가 이하로 하락시킨 사례가 다수 발생하였다. 검찰은 이를 시세조종이라는 이유로 기소하였고, 투자자들은 상환금 또는 손해배상금을 청구하는 민사소송을 제기하였다. 발행자들은, 상환평가일에 대량으로 기초자산을 매각한 것은 델타헤지라는 위험회피기법에 따른 것이고, 이는 시장의 자연스러운 수급질서의 한 내용을 이루는 것이므로 시세조종이 아니라고 반박하였다. 하급심 법원은 발행자들의 주장을 받아들여 손해배상 청구를 기각하였다. 그러나 법원의 판단에는 찬성하기 어렵다. 델타헤지를 위해서는, 델타값이 상승하면 기초자산을 더 매수하고 델타값이 하락하면 보유하던 기초자산을 매도하여야 한다. 위 분쟁에서 발행자들은 상환평가일에 델타값이 급격히 상승하고 있는 상황에서 보유하고 있던 주식을 대량으로 매도하였다. 이러한 행위는 델타헤지로 설명될 수 없다. 법원의 판단은 재고되어야 한다. ELS, Equity-Linked Securities are a kind of derivative linked securities. The amount of repayment is decided, depending on the price of underlying securities at maturity. At maturity, if the stock price is beyond the striking price, investors will receive both the principal and high gains. On the contrary, if the stock price falls below the pre-set price, investors’ original pricipal can be diminished. Here, conflict of interest between the issuer of ELS and the investors occur. Many cases have happened, where the issuer of ELS sold the underlying stocks in a large quantity at maturity and as a result, the price of the stock fell to under the striking price, which let the investors lose their money. In some of those cases, the traders of the issuers were prosecuted in charge of manipulation. The investors sued issuers for damages. In those litigations, issuers argued that their mass-sales of underlying securities were lawful, because they followed the principle of delta hedge, which is one of generally accepted risk managing devices in the capital market. The appellate court agreed to the argument of the issuers and dismissed the suits. I do not agree with the decisions of the courts. According to the principle of delta hedge, the issuer can offset the loss by the profit only when he or she holds underlying securities corresponding to the delta. But in above litigated cases, the issuers sold most of the underlying securities they had held in spite of rising delta. These actions cannot be explained by the delta hedge principle. There are enough evidence to suspect the issuer of intentionally manipulating stock price. The decisions of the appellate court should be reconsidered.
김창희(Changhee Kim),연성현(Seonghyeon Yeon),김규영(Kyuyoung Kim),이남수(Namsoo Lee),조용(Yong Cho) 대한설비공학회 2022 대한설비공학회 학술발표대회논문집 Vol.2022 No.11
Heat pump systems offer economical alternatives of recovering heat from different sources for use in various industrial, commercial and residential applications. Heat pump becomes a key component in an energy system with great potential for energy saving. This paper presents the design process and experimental results of oil-free water-source heat pump system. A set of experimental tests was first carried out to examine the performance of heat pump system under three different operating conditions.
소셜커머스 모바일 어플리케이션의 품질 개선 요인에 대한 분석
김창희(Changhee Kim),천민기(Min Ki Chon),김현정(Hyun Jung Kim) 한국SCM학회 2016 한국SCM학회지 Vol.16 No.1
This study was conducted to analyze the quality of the social-commerce application, one of the fastest growing Mcommerce platforms in Korea. Refer to preceding research, this study classified seven categories of qualities of social-commerce mobile application ; product supply, provision of information, appearance, stability, convenience, ease of use, and enjoyment. In the empirical level, this study was conducted using Importance Performance Analysis through 17 factors of quality in social-commerce mobile application. This study found that customers are satisfied with the three service quality factors by IPA analysis; safety, product supply, and convenience. And customers have low importance and low satisfaction in the ease of use factor. Also, Customers does not emphasis on the Enjoyment factor. However, customers have low satisfaction relative to importance in provision of information factor. This study gives implication thorough analyzing the factors of quality for the fast growing social-commerce mobile application using IPA Matrix.
진동형 히트파이프 흡열판이 결합된 하이브리드 태양광/열 시스템
김창희(Changhee Kim),전동환(Donghwan Jeon),공상운(Sangun Kong),김종수(Jongsu Kim) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5
The electricity conversion-efficiency of solar cell for commercial application is about 6-15%. More than 85% of the incoming solar energy is either reflected or absorbed as heat energy. Consequently, the working temperature of the photovoltaic cells increases considerably after prolonged operations and the cell's efficiency drops significantly. PV/T refers to the integration of a PV module and a solar thermal collector in a single piece of equipment. By cooling the PV module with a fluid steam like air or water, the electricity yield can be improved. At the same time, the heat pick-up by the fluid can be to support space heating or service hot-water systems. In this study, a pulsating heat pipe solar heat collector was combined with single-crystal silicon photovoltaic cell in hybrid energy-generating unit that simultaneously produced low temperature heat and heat and electricity. This experiment was investigating thermal and electrical efficiency for evaluation of a PV/T system.