능동 선형 자석 기어의 자기력 특성 해석

이상헌,정광석,Sangheon Lee,Kwangsuk Jung 한국교통대학교 융복합기술연구소 2024 융ㆍ복합기술연구소 논문집 Vol.14 No.1

In order to amplify magnetic force in a linear magnetic gear, the high-speed magnet must move more than the low-speed magnet by the amplification ratio. Due to limitations in overall size, this topology has limited applications. In this study, we introduce an active magnetic gear that implements a moving magnetic field instead of the mechanical movement of the magnet by replacing the high-speed side magnet with a linear coil. In the proposed system, a harmonic modulator is added to increase the number of poles of the low-speed magnet, thereby suppressing the decrease in magnetic field strength due to size limitations of the low-speed magnet. The possibility of replacing the existing system was confirmed through harmonic magnetic analysis in the air gap, and the magnetic force change characteristics according to the added modulator variable were simulated.

도시관리사업의 해외 진출방안 연구: 쿠웨이트 신도시를 대상으로

이상헌,정연우,Lee, Sangheon,Jeong, Yeun-Woo 한국토지주택공사 토지주택연구원 2022 토지주택연구 Vol.13 No.2

This study reviews urban infrastructure and housing management in Kuwait to establish a strategy for going abroad in an urban management sector after the construction of the Kuwait New Town. This study reviews legal systems and governance related to urban infrastructure and housing management as well, offering implications that are collated from international and Korean case studies. By doing so, this paper proposes a governance structure for urban infrastructure and housing management along with key agendas for local institutional improvements. This study suggests that the establishment of a legal system equivalent to the Korean Multi-family Housing Management Act is a key to institutional improvements. The (tentatively entitled) 'Housing Management Act' is proposed to specify the scope and the ways of management in mandatory management subject to local conditions. The direction of going abroad, such as the management scope and the implementation system, discussed in this study can be used as a reference when expanding into other countries in the Middle East that have similar institutional environments to Kuwait in urban infrastructure and housing management.

화분 · 포자

이상헌(Sangheon YI),봉필윤(Pil Yoon BONG),이명석(Myung-Suk YI) 한국고생물학회 2004 한국고생물학회 단행본 Vol.2004 No.6

초광대역 M-ary IR 시스템의 협대역 간섭 억압에 관한 연구

이상헌(SangHeon Lee),이양선(YangSun Lee),강희조(HeauJo Kang) 한국정보기술학회 2005 한국정보기술학회논문지 Vol.3 No.3

In this paper, we analyzed performance of M-ary Impulse Radio(IR) system. As a results, we could know that is degraded performance of IR system by narrowband interference and multiple access interference in used bandwidth. Thus, this paper described the performance evaluation of IR system with Notch filter using the Complex Multirate Filter Bank for cancel narrowband interference from recevied IR signals.

사물인터넷 기반 무선 상태 모니터링 시스템 개발

이상헌(SangHeon Lee) 한국생산제조학회 2020 한국생산제조학회지 Vol.29 No.4

With the advancements in sensor technology and open source-based controllers, the development of a condition monitoring system has become relatively easier. However, there is not enough well-organized information to develop condition monitoring system. Therefore, we present a wireless condition monitoring system based on the Internet of Things (IoT) by using an open-source controller. The developed wireless condition monitoring system consists of a sensor module, data processing unit, and condition monitoring program. This system can measure 3-axis accelerations of frequency up to 1.5 kHz, with a frequency resolution of 0.05 Hz to 20 Hz, and temperature. The developed condition monitoring system provides statistical time information and frequency spectrum for advanced condition diagnosis. Furthermore, the condition diagnosis function for low-speed rotating machines was implemented effectively.

마르크스 경제학의 금융적 성장변동 모형 - 노동자, 산업자본가 그리고 금융자본가 사이의 계급갈등을 중심으로

이상헌(Lee Sangheon) 한국사회경제학회 2007 사회경제평론 Vol.- No.28

  우리는 우선 구드윈의 성장변동 모형과 유효수요이론을 결합하여 균형성장 경로의 변동현상을 설명할 수 있는 구드윈-해로드 모형을 구축하였다. 그리고 산업자본가와 금융자본가 사이의 계급갈등 관계를 포함하도록 이 모형을 변형하여, 마르크스 유형의 금융적 성장변동 모형을 구축하였다. 후자의 모형은 유효수요이론의 균형조건을 금융제약조건으로 대체하였으며, 노동자와 산업자본가 그리고 금융자본가 사이의 계급갈등과 금융신용정책 그리고 기술변화를 나타내는 매개변수들을 포함하고 있다. 동 모형에 대한 비교동태 분석에 의하면, 노사 간의 갈등은 그 결과에 관계없이 장기균형 실질임금률에 영향을 미치지 않으며, 자본가 계급의 내부갈등 및 금융신용정책은 장기균형 생산과 고용 수준에 영향을 미치지 않는다.   This paper presents a Marxian model of financial growth cycles with class struggle among workers, industrial capitalists and financial capitalists. We first develop a Goodwin-Harrod model of Lotka-Volterra equation system, and explain equilibrium paths of endogenous growth cycles in real economy. Then we construct a Marx-Goodwin model to explain financial growth cycles with class struggle among three classes. The key devices of the latter model consist of (ⅰ) the equation of interest rate to describe class struggle between financial and industrial capitalists, (ⅱ) the condition of financial restriction and (ⅲ) the parameters to represent class struggle, financial policies and technical changes. We also present comparative dynamic analyses and explain the effects on equilibrium paths of growth cycles of class struggle, financial policies and technical changes.

Late Holocene paleoenvironmental changes inferred from palynological and diatom assemblages in Isanpo area, Ilsan, Gyeonggi-do, Korea

이상헌(Sangheon Yi),류은영(Eunyoung Ryu),김주용(Ju-Yong Kim),남욱현(Wook-Hyun Nahm),양동윤(Dong-Yoon Yang),신숙정(Sook-Chung Shin) 대한지질학회 2005 지질학회지 Vol.41 No.3

Abundant and diverse palynofloras and diatoms have been recovered from Trench BH-4 of Isanpo area, Ilsan located in river-mouth of the Han River. These terrestrial and marine derived assemblages reflect that the paleoenvironmental changes have occurred during the past 2300 years. Erected pollen zone (2 pollen zones and 4 pollen subzones) and diatom zone (2 diatom zones and 6 diatom subzones) indicate that depositional environments have changed from estuary to lowland fluvial plain about 1800 ¹⁴C yr BP. During 2300 ~ 1800 ¹⁴C yr BP, Pollen Zone I and Diatom Zone I, elevation 3.31 ~ 2.74 m, are characterized by the abundance of hyposaline marine-brackish dinoflagellates and diatoms together with freshwater algae indicating an estuary surrounded by mountain-slope on which mixed coniferous-deciduous broadleaved vegetation forest flourished under wet, warm Temperate climatic conditions. On the other hand, Pollen Zone II and Diatom Zone II, elevation 3.72 ~ 3.36 m, are dominated by only freshwater diatoms and common freshwater algae without marine taxa of dinoflagellates and diatoms. These assemblages refer to be lowland fluvial plain that there were river or small ponds since about 1800 ¹⁴C yr BP. Sterilized mountain soil conditions, caused by human activity such as deforestation and cultivation, accelerate an expansion of coniferous vegetation forest replacing the former mixed vegetation forest. The human impact is indicated by the occurrences of cultivated plants, Gramineae, Zea and Fagopyrum combined with synanthropogenic habitats of Ambrosia and Artemisia.

Palynofacies of the Cretaceous sediments in the Tando Basin, West Korea: thermal maturation and its geological implication

이상헌(Sangheon Yi),이융남(Yuong-Nam Lee),이성주(Seong-Joo Lee) 대한지질학회 2004 지질학회지 Vol.40 No.4

A few of palynodebris such as wood fragments and cuticles are yielded without pollen and spores from the palynological outcrop samples of the Tando Basin in the Tando area of Ansan City, Gyeonggi-do. The palynofacies consisting of these palynodebris implies both syn- and post-depositional environmental and geological events. The paleoenvironments are interpreted to be fluvio-lacustrine and/or alluvial plain as indicated by an opaque and black palynodebris (150-185 µm in long axis) with normal sorting and poor roundness. The palynodebris had been firstly oxidized in the fluvio-lacustrine and/or alluvial plain by being easily exposed to the air. And then, the volcanic emplacements and eruptions occurred along the faults after the deposition made the organic matters metamorphosed so that they became opaque and black in color. The color of the palynofacies is correlated with 6-7 of Thermal Alteration Index (TAI), which indicates that the palynodebris were thermally altered at about +200℃(Batten, 1996).

경기도 여주군 하거리 방미기골 백제 석실분에서 산출된 포자, 화분분석

이상헌(Sangheon YI),강봉원(Bong Won KANG),윤혜수(Hyesu YUN) 한국고생물학회 1999 고생물학회지 Vol.15 No.2

임베디드 시스템에서 고해상도 멀티미디어 플레이어 설계 및 구현

이상헌(Sangheon Lee),군순영(Soonyoung Kwon),이동하(Dongha Lee),이상혁(Sanghyuk Lee) 한국멀티미디어학회 2007 한국멀티미디어학회 학술발표논문집 Vol.2007 No.1

디지털 컨버전스 환경에서 모바일 기기를 중심으로 다양한 기능들이 통합되고 있다. 각 기능 들이 통합되면서 예전보다 더 높은 CPU 성능, 배터리 용량, 메모리 등이 필요하게 되었다. 본 논문에서는 현재 사용자들을 널리 확보해 가고 있는 모바일 기기인 PMP(Portable Multimedia Player)에서 성능이 한층 강화된 TI(Texas Instruments)에서 출시한 DM6441 CPU를 기반으로 한 고해상도 멀티미디어 플레이어를 구현하였다. 다양한 MPEG-1/2/4비디오 코텍 뿐만 아니라 최근 DMB에서도 각광받고 있는 고성능 비디오 코텍인 H.264와 최대 XGA급(1024×768)의 동영상을 무리없이 재생활 수 있어 휴대형 멀티미디어 플레이어 시장에서 경쟁력을 확보할 것으로 기대된다.