Ad-hoc 네트워크에서 다중경로를 지원하는 ATP 프로토콜에 대한 연구

이학주,장재신,이종협,Lee, Hak-Ju,Jang, Jae-Shin,Lee, Jong-Hyup 한국시뮬레이션학회 2009 한국시뮬레이션학회 논문지 Vol.18 No.3

Wireless networks have several unique features : node mobility, restricted bandwidth, time-variable bandwidth, large latency, and high bit error rates time due to channel fading. These features at wireless networks intend to decrease the performance TCP protocols are used in wireless networks. Lots of studies have been done for finding appropriate wireless transport protocols for current wireless communications. However, related studies have not provided good performance or some protocols have a good performance only in specific circumstances. Thus, these are not suitable for general wireless circumstance. Therefore, we propose a new wireless transport protocol which provides better performance than the previous ones. And we'd like to solve a problem that previous protocols cannot maintain their connections even though they have multiple paths until another path is successfully set up. To solve these problems, a new protocol ATP-M is proposed which is designed on already known TCP-M and ATP protocols. With NS-2 computer simulation, it is shown that this newly proposed protocol has better system throughput than TCP, TCP-M and ATP protocols.

IP R&D 연계를 위한 마이크로그리드기술 특허 분석

이학주,Lee, Hak-Ju 대한전기협회 2012 전기저널 Vol.- No.424

마이크로그리드용 10[kW] PCS 개발 및 성능시험

이학주,채우규,박중성,김주용,김찬영,Lee, Hak-Ju,Chae, Woo-Kyu,Park, Jung-Sung,Kim, Ju-Yong,Kim, Chan-Young 한국조명전기설비학회 2011 조명·전기설비학회논문지 Vol.25 No.7

PCS(Power Conditioning System) is the necessary component in Microgrid, composed of multiple distributed generators and energy storage system. In this paper, the functions of PCS are defined and 10[kW] PCS for PV and BESS are developed. To apply PCSs to Microgrid, this paper presents a 3-phase inverter with the decoupling current controller, voltage controller and DPLL control system. PCSs were applied to 120[kW] pilot plant and its performance tests were carried out. Test results of PCS at each operation mode show stable in Microgrid.

동력차용 대차프레임의 피로강도평가

이학주,한승우,이상록,Lee, Hak-Ju,Han, Seung-U,Augagneur Sylvain,Lee, Sang-Rok 한국기계연구원 1997 硏究論文集 Vol.27 No.-

The bogie between the track and the railway vehicle body, is one of the most important component in railroad vehicle. Its effects on the safety of both passengers and vehicle itself, and on the overall performance of the vehicle such as riding quality, noise and vibration are critical. The bogie is mainly consisted of the bogie frame, suspensions, wheels and axles, braking system, and transmission system. The complex shapes of the bogie frame and the complicate loading condition (both static and dynamic) induced in real operation make it difficult to design the bogie frame fulfilling all the requirements. The complicated loads applied to the bogie frame are i) static load due to the weight of the vehicle and passengers, ii) quasi-static load due to the rolling in curves iii) dynamic load due to the relative motion between the track, bogie, and vehicle body. In designing the real bogie frame, fatigue analysis based on the above complicated loading conditions is a must. In this study, stress analysis of the bogie frame has been performed for the various loading conditions according to the UIC Code 6 15-4. Magnitudes of the stress amplitude and mean stress were estimated based on the stress analysis results to simulate the operating loads encountered in service. Fatigue strength of the bogie frame was evaluated by using the constant life diagram of the material. 3-D surface modelling, finite element meshing, and finite element analysis were performed by Pro-Engineer, MSC/PATRAN, and MSC/NASTRAN, respectively.

Special Issues - 마이크로그리드 기술 개요 및 현황

이학주,Lee, Hak-Ju 대한전기협회 2011 전기저널 Vol.414 No.-

화천의 동제(洞祭)와 성(性)신앙

李學周(Lee, Hak-ju) 아시아강원민속학회 2005 江原民俗學 Vol.19 No.-

신숭겸 설화의 영웅적 형상화 연구

李學周(Lee, Hak-ju) 아시아강원민속학회 2006 아시아강원민속 Vol.20 No.-

양양군 수동골 마을제사 연구

李學周(Lee Hak-Ju) 중앙어문학회 2009 語文論集 Vol.42 No.-

This thesis wrote about village rites in sudong-gol in yangyang-gun. Sudong-gol is consist of six ri include Yib-am-ri. This village is bounded with Yangyang-gun and Gangneung-si and so that it has both culture's characters. Even though is surrounded with mountain, field and sea, it didn't have any folk about sea. Sudong-gol has won many prises from folk art competitions. Beach opening rites and sun rising rites are the new folk that they had created. That is why it has very unique folk culture. we can devide the village rites into ‘tradition transmitted village rites’ and ‘modern commercial village rites’. The former has Seonangje(the festival of the local god), GiwuJe(a ritual for rain), Daewangje(rites for king) and Muhuje(rites for the childness ancester) from the ancient time. The other was started from the commercial reason and there are beach opening rites and sun rising rites. Most of tradition transmitted village rites don't exist any longer or changed. Sudong-gol is not an exception. In case of Seonangje(the festival of the local god), two places were burn down and due to the low participation one place don't perform it anymore. On the other hand, there are four places where they have kept it very well. Daewangje(rites for king) in Sangwolcheon-ri doesn't exit anymore. Giwuje(a ritual for rain) in Hawolcheon-ri can be held whenever there is a drought. Muhuje(rites for the childness ancester) has been handed down just as like tradition or transformed. Village people are keen to it and the change is quite slow. Mordern commercial rites are for producing profit related to the beach only in Wonpo-ri and Jigyeong-ri. The rites can be ceased anytime when the beach is closed permanently. However this commercial rites perform Daewangje(ritual for the sea king) which it has never done in Sudong-gol and also has very special rites such as Sansinje(ritual for the god of a mountain) and Hwasangamje(ritual for the Hwasang rock). These rites have been done on a basis of beach and has strong business wise purpose.

저령(Grifola umbellata)균핵의 추출성분

이학주(Hak-Ju Lee),이경태(Kyoung-Tae Lee),박영기(Youngki Park),이민웅(Min-Woong Lee) 한국산림바이오에너지학회 2002 산림바이오에너지 Vol.21 No.1

저령의 균획으로부터 3개의 알카로이드와 2개의 스테로이드 화합물을 분리하였다. 단리된 물질들은 NMR, MS 등의 기기분석에 의해 9-β-D-ribofuranosyladenine (adenosine)을 비롯하여 1-β-D-ribofuranosyluracil (uridine), 그리고 2, 4-pyrimidinedione (uracil)과 ergosta-4, 6, 8 (14), 22-tetraen-3-one, ergosta-5, 7, 22-triene-3β-ol (ergosterol)으로 각각 동정하였다.<br/> Three alkaloids and two steroids were isolated from the sclerotia of Grifola umbellata. Structures of the isolated compounds were determined as 9-β-D-ribofuranosyladenine (adenosine), 1-β-D-ribofuranosyluracil (uridine), 2, 4-pyrimidinedione (uracil), ergosta-4, 6, 8 (14), 22-tetraen-3-one and ergosta-5, 7, 22-triene-3β-ol (ergosterol) respectively on the basis of spectroscopic data and chemical correlations.<br/>

양구군 후곡리 서암제와 기우제문의 구성 분석 : 김현도 현감의 백성에 대한 애정

이학주(Lee, Hak-ju) 아시아강원민속학회 2022 아시아강원민속 Vol.37 No.-

이 글은 제 대 양구현감을 지낸 김현도 현감에 대한 연구이다. 김현도 현감은 양구 서암사(書巖祠)에서 양구 현감 중 유일하게 제향을 받고 있다. 본고에서는 김현도가 서암사에 제향 되는 이유와 그가 쓴 기우제문에 대한 분석을 했다. 김현도 현감은 임금께 상소를 올려 양구사람들의 세금을 감면하고, 동궁(東宮)을 지을 때 벌목작업을 줄였으며 굴토(掘土)하는 사람에게 품삯을 주게 했다. 그리고 무엇보다 향교를 중수하고 양구사람들에게 글을 가르쳤다. 이런 업적으로 선조로부터 『사서삼경』에 성심애민(誠心愛民) 진직불태(盡職不怠)라고 쓴 어포(御褒, 임금의 포상)를 받기도 했다. 이런 업적 중에서 양구사람들은 글을 가르친 사실을 가장 높은 치적으로 보았다 이율곡에 버금가는 거유(巨儒)라 했다 그래서 서암사(書巖祠)라는 사당을 짓고 제향을 했다. 그는 가뭄이 오래되자 기우제를 지내서 양구의 백성들을 달래기도 했다. <그의 도솔산 기우문>이 전하고 있다. 이 기우제문은 운문과 산문을 섞은 독특한 양식이다. 그래서 초사(楚辭)를 차용한 무가(巫歌)의 양식을 썼다고도 한다. 그는 운문을 통해서는 감성과 감정을 표현했고 산문을 통해서는 직설적으로 비를 기원했다. 그러면서 비유와 상징도 간혹 넣어 문학성이 두드러지게 했다. 내용은 목민관인 현감의 잘못을 용서하고 백성들을 위해 비를 내려 달라고 했다. This studies Kim Hyeondo, 14th county governor of Yanggu. He is the only governor who receives worship at the shrine. This study reasons about it. Kim appealed the king for exempt of tax, for reduction of work in building of the palace of crown prince and for paying for the diggers. First of all, he raised the people’s literacy and rebuilt the Confucian school. The people regarded him the great Confucianist next to Lee Yulgok, built SeoAm Shrine, have offered worship. He soothed the people with the praying for rain in long drought. His “Prayer for Rain in Mt.Dosol” delivers the prayer. It is mixed with poem and prose. He expressed emotion with poem, praying with prose. It has some metaphors and symbols which adds literary elements. He asks forgiveness of governor’s misdeeds and rain for the county people.