Mach-Zehnder 변조기를 이용한 Loop-back System

김희주,강동성,전금수,반재경,Kim, Hui-Ju,Gang, Dong-Seong,Jeon, Geum-Su,Ban, Jae-Gyeong 대한전자공학회 2001 電子工學會論文誌-SD (Semiconductor and devices) Vol.38 No.7

본 논문에서는 광원이 불필요하며 단일 광섬유를 통하여 양방향 전송이 가능한 BS(base station)용 광송 수신기 모듈을 제안한다. 본 논문에서 제안하는 방식에서는 BS의 송신단에서 Ring type으로 구성된 Mach-Zehnder 변조기의 양방향 변조를 이용하여 CO(central office)에서 제공된 광원을 변조하여 다시 CO로 전송한다. Ring 타입으로 구성된 변조기의 등가모델을 도출하였으며, 등가모델과 측정결과가 매우 잘 일치함을 확인할 수 있었다. 또한 Ring type에서 Mach-Zehnder 변조기의 광학적인 대칭이 RF 신호 전송 특성에 중요한 영향을 미침을 확인할 수 있었다. In this paper, we propose optical subcarrier mutiplexing(SCM) transceiver module for base station(BS) that has no optical source and can be used for full-duplex communication over single optical fiber. In this method we retransmit optical modulated signal to the central office(CO) using loop-back system with a ring type Mach-Zehnder modulator(MZM) in BS, where optical source is transmitted from the CO. We have modeled the ring type MZM and were conformed that the measured results were in good agreement with the modeling. In the ring type MZM, the optical symmetric position of the MZM is very important in RF signal transmission.

호기/혐기 조건에서 Membrane을 이용한 NDMA(N-nitrosodimethylamine)제거

김희주,정진욱,최창규,김문일,Kim. Hui-Joo,Chung. Jin-Wook,Choi. Chang-Kyoo,Kim. Moon-Il 한국방재학회 2008 한국방재학회 학술발표대회논문집 Vol.2008 No.1

Recently, the interest in NDMA(N-nitrosodimethylamine) has increased due to its recognition as a pollutant by Ontario Ministry of Environment and Energy and California Department of Health Sciences. It is, in fact, one of the DBPs(Disinfection By-products) which appears due to chlorination and is reported to be fatal if exposed continuously to human body. Due to uncertainty in mechanism to remove it, its treatment is not yet carried out. In this experiment, treatment of biological NDMA is carried out by letting it adsorbed on Granular Sludge and then filtering the medium through MF(Microfiltration) and UF(Ultrafiltration) membranes. Granular Sludge is adapted to aerobic and anaerobic conditions for 7 days and the experimental conditions are MLSS of 8000mg/L, COD of 250mg/L, TN of 12.5mg/L, and TP of 2.5mg/L. Several batch tests were carried out and samples were collected with the interval of 1 hour. Samples were measured by LSC(Liquid scintillation counter) after filtering by MF and UF. In batch test with granular sludge the permeate concentrations(removal efficiencies) of NDMA by MF and UF were 71.7ng/L(32.0%) and 62.0ng/L(43.7%) at aerobic state, and 52.0ng/L(49.2%) and 47.6ng/L(58.9%) at anaerobic state, respectively. Hence, UF membrane showed about 10% more removal efficiency than MF and removal efficiency at anaerobic condition was 15% more than that at aerobic condition.

강재교각 기초부의 연결상세 개선을 위한 실험적 연구

김희주,함준수,양성돈,황원섭,Kim, Hee-Ju,Ham, Jun-Su,Yang, Sung-Don,Hwang, Won-Sup 한국강구조학회 2012 韓國鋼構造學會 論文集 Vol.24 No.5

현재 강재교각 기초부의 설계에 적용되어지고 있는 형식은 기초 콘크리트 내부에 앵커프레임을 설치하여 교각부와 연결하는 형태로 설계 및 시공을 하고 있다. 이는 복잡한 설계와 시공으로 인하여 기초부의 크기가 커지고, 과대 설계되는 경향이 있다. 본 연구에서는 고성능강을 이용한 교각 기초부의 연결상세와 관련하여 새로운 형상을 제안하기 위하여 기존 설계기준에 의한 시험체와 고장력 앵커를 사용한 새로운 연결형상 시험체 등 총 3개의 시험체를 제작하여 실내 시험을 실시하였다. 이를 통하여 각 시험체의 성능을 비교 분석하여 연결형식에 따른 구조물의 거동특성을 분석하였다. Generally, a steel pier-foundation has been designed and constructed with a anchor frame. However, because of the complicated design and construction, the foundation's size has become large and has been overdesigned. In this study, three specimens were made and the tests were conducted to suggest a new shape in regard to the pier-foundation's joint details using the high performance steel. One of the specimens was made up of the general anchors and the anchor frame. Another specimen consisted of the high tension anchors and the studs, and the other specimen was composed of the high tension anchors and the inner steels. After the performance of each specimen was compared and analyzed, the behavior characteristics according to the joint were analyzed.

열다한소탕(熱多寒少湯) 가감방(加減方)의 자가탐식(自家貪食) 유도 활성과 관련 단백질 탐색

김희주,배나영,장문희,양현옥,안택원,Kim, Hee-Ju,Bae, Na-Young,Jang, Moon-Hee,Yang, Hyun-Ok,Ahn, Taek-Won 사상체질의학회 2013 사상체질의학회지 Vol.25 No.3

Objectives Modified Yeolda-Hanso tang (MYH) is a traditional herbal formula in Korea for various diseases. MYH is containing the 10 herbs : Pueraria lobata (Willd.) Ohwi, Angelica tenuissima Nakai, Scutellaria baicalensis Georgi, Platycodon grandiflorum (Jacq), Angelicae Dahurica, Cimicifuga heracleifolia Kom, Raphanus sativa L., Polygala tenuifolia (Willd), Acorus gramineus Soland and Dimocarpus longan Lour. The 10 herbs is constituted as a ratio of the 6:4:2:1:2:2:2:4:6:6. We investigated neuroprotective effects of MYH on human neuroblastoma SH-SY5Y cells and evaluated the ability of MYH to prevent and treat for neurodegenerative diseases such as Parkinson's disease via basal autophagy enhancement. Methods Pharmacological induction of Autophagy by MYH in SH-SY5Y cells: Induction of autophagy by MYH in human neuroblastoma SH-SY5Y cells was carreid out by immunoblot analysis with several autophagy markers. SH-SY5Y cells were treated with MYH at the concentration of 400 and $800{\mu}g/ml$ for 24 hr. Specifically, the autophagosome proteins LC3 II and Atg5 levels were increased and autophagy pathway related proteins such as beclin-1, PI3 Kinase class III protein, ULK1, mTOR and AMPK were activated. Conclusions MYH can enhance the induction of autophagy through key regulator AMPK, mTOR, and Beclin-1 and it should be considered as a possible candidate of neuroprotective agents for such as Parkinson's disease.

저상굴절차량의 주행에 따른 파이프트러스교의 충격계수 산정

김희주,전명일,황원섭,Kim, Hee-Ju,Jun, Myung-Il,Hwang, Won-Sup 한국전산구조공학회 2010 한국전산구조공학회논문집 Vol.23 No.1

본 논문에서는 새로운 차량의 도입으로 건설되는 신형식 교량의 동적거동을 확인하기 위해 상용 유한요소 프로그램을 이용하여 해석을 실시하여 충격계수를 산정하였으며, 국내뿐만 아니라 각국에서 적용되고 있는 충격계수에 관한 설계기준을 조사하여 비교 검토하였다. 연구에서 제시되어진 교량형식은 파이프트러스 형식으로 각각 34m, 44m, 54m로 모델링하였으며 각각의 지간길이에 따른 충격계수의 영향을 산정하였다. 차량모델은 실제 교량 위를 통과하는 2축과 3축 저상굴절차량과 박영석(1997)이 제시한 147kN 덤프트럭 모델을 적용하였으며, 각 차량별로 10km/h~100km/h까지의 속도대역에 따른 충격계수를 산정하여 이에 따른 영향을 검토하였다. 또한 차량 및 지간길이에 따라 산정되어진 지간 중앙에서의 충격계수를 바탕으로 우리나라 및 외국의 설계규정과 비교 검토하였다. This paper estimated the impact factor using the finite element program to confirm the dynamic behavior of new type of bridges constructed by introduction of new vehicles and compared the design criteria about the impact factor applied to domestic as well as each country. The study estimated effects of the impact factor according to pipe truss types modeled as respectively 34m, 44m, 54m and span length. The vehicle models are vehicle for bimodal tram of two axis and three axis which passes on actual bridge and dump truck model proposed by Park Young suk(1997). Each vehicle is estimated the impact factor according to velocity from 10 to 100(km/h) and examined. Also, the study investigated and compared the design regulation of domestic and a foreign country based on the impact factor on span center calculated in accordance with vehicle and span length.

토끼 심방근 및 혈관 평활근에서의 $Na^{+}/Ca^{2+}$ 교환기전에 관한 연구

김희주,문형로,엄융의,호원경,Kim, Hee-Ju,Moon, Hyung-Ro,Earm, Yung-E,Ho, Won-Kyung 대한생리학회 1988 대한생리학회지 Vol.22 No.1

In order to elucidate the regulatory mechanism of intracellular calcium ion concentrations, contractions or contractures induced by $Na^{+}-removal$, calcium-application or ouabain-treatment as an index of $Na^+/Ca^{2+}$ exchange activity were studied in atrial muscle or vascular smooth muscle (aorta and renal artery) of the rabbit. The magnitude of low sodium contractures in atrial trabeculae increased with sigmoid shape when external sodium concentrations were reduced to sodium-free condition, whereas that of calcium contracture intensified in a parabolic pattern when external calcium concentrations were elevated to 8 mM. $Na^{+}-removal$ contractures were induced in a duration-dependent manner to $K^{+}-free$ exposure and same findings were observed with ouabain treatment. $Na^{+}-free$ contractures were not affected by verapamil treatment, but stimulated by $100{\mu}M\;Mn^{2+}$ and inhibited by high concentrations of $Mn^{2+}\;(2{\sim}8mM)$ in a dose-dependent manner. Ryanodine which is known to suppress the release of calcium from internal store abolished spontaneous twitch contractions induced by $K^{+}-free$ solution, but had no effect on the development $Na^{+}-free$ contractures. Na-free contractures were not always induced in vascular smooth muscle preparations. Contractures by $O\;mM\;Na^+$ were usually seen in aorta, but not often in renal artery.$50\;mM\;K^+$, noradrenaline (NA) and angiotensin II (AII) always evoked very large contraction in all preparations of vascular smooth muscle. Contractures developed by $O\;mM\;Na^+$ were not sensitive to verapamil treatment as in atrial trabeculae, but were abolished by $100{\mu}M\;Mn^{2+}$. In contrast to $Na^{+}-free$ contractures, $Mn^{2+}(100{\mu}M)$ had no effect on the contractures induced by NA or 50 mM$K^+$. Caffeine in the concentration of 10 mM evoked transient contracture in the distal renal artery. The rate of spontaneous relaxation in caffeine contracture was dependent upon the concentrations of external sodium, and had double component of relaxation when the rate of relaxation was plotted in the semilogarithmic scale of relative tension versus time. Especially late components of relaxation had more direct relation to $Na^+$ concentrations. It could be concluded that $Na^+/Ca^{2+}$ exchange mechanism in the heart has a large capacity, inhibited by $Mn^{2+}$ but not by verapamil and ryanodine, while $Na^+/Ca^{2+}$ exchange system in vascular smooth muscle has a very low capacity especially in small artery, inhibited by low concentration of $Mn^{2+}\;(100{\mu}M)$ but not affected by verapamil and ryanodine.

원전사고에 따른 토양.지하수 방사성오염의 효과적인 관리 연구

김희주,현윤정,김영주,황상일,Kim, Hee-Joo,Hyun, Yun-Jung,Kim, Young-Ju,Hwang, Sang-Il 한국지하수토양환경학회 2011 지하수토양환경 Vol.16 No.6

In this study, we suggested the management scheme of analyzing the national and oversea related policy against soil and groundwater contamination by radioactive materials due to nuclear accidents. In Korea, we need to remedy swiftly the contaminated land due to intensive land development demand. So, we need to develop more effective management scheme to recover actively the land contaminated by radioactive materials. We require to improve monitoring network, to expand media-specific monitoring system, to prepare management system for remediation of contaminated land, and to develop flow work for soil and groundwater remediation.

PEG-free 계면활성제를 사용한 Nanoemulsion의 안정화

김희주,정택규,김자영,윤경섭,Kim, Huiju,Jung, Taek Kyu,Kim, Ja Young,Yoon, Kyung-Sup 한국응용과학기술학회 2019 한국응용과학기술학회지 Vol.36 No.2

폴리에틸렌글라이콜(PEG)은 계면활성제, 세정제, 유화제 등으로 화장품에 많이 사용된다. 이들은 제조 과정 중, ethylene oxide의 이량체화에 의해 인간에 몸에 유해한 1,4-dioxane이 부산물로 생성될 수 있다. 화장품 성분에 대한 소비자들의 관심이 증가함에 따라, 퍼스널케어 시장에서 PEG 성분이 없는 보다 안전한 에멀젼 연구의 필요성이 증대되고 있다. PEG-free 계면활성제로 사용되는 polyglycerol ester (PGE)는 비이온성 계면활성제로서 식품, 화장품 등의 분야에서 많이 사용되며 글리세롤과 지방산을 에스테르화 하여 생산된다. 본 연구에서는 PEG 성분을 함유하지 않은 나노에멀젼 제형의 개발 및 안정화를 목표로 하였다. 최적화된 나노에멀젼 제형 개발을 위해 RSM (Response Surface Methodology)를 사용하였다. 독립변수 및 변수의 범위 결정을 위한 예비 실험의 결과로 계면활성제 함량(2~4%), 오일 함량(4~8%), 폴리올 함량(12~24%)을 독립변수로 설정하였다. 반응변수로는 제형의 입자 크기(particle size), 제타 전위(zeta potential), 현탁도(turbidity), 다분산지수(polydispersity index)를 측정하였다. 제조한 나노에멀젼을 FIB (Focused ion beam)로 측정한 결과, 구형의 입자들이 100~200 nm의 크기를 가지고 분포되어 있는 것을 확인하였다. 제조된 제형에 대해 30일 간 각 온도별($4^{\circ}C$, $25^{\circ}C$, $45^{\circ}C$) 안정성 평가를 진행하였고, 최적의 입자 크기, 현탁도, 다분산지수, 제타 전위를 고려한 최적의 처방은 계면활성제(2%), 오일(8%), 폴리올(24%)로 확인되었다. Polyethylene glycol (PEG) is widely used in cosmetics as a surfactant, detergent and emulsifier. During the manufacturing process, 1,4-dioxane, which is toxic to humans, can be produced as a by-product by dimerization of ethylene oxide. As consumers' interest in cosmetic ingredients has increased, the need for safe emulsion research without PEG ingredients in the personal care market has increased. With increasing consumer interest in cosmetic ingredients, the need for safer emulsion research without the PEG ingredient in the personal care market has increased. In this study, we aimed to develop and stabilize nanoemulsion formulation without PEG. Response Surface Methodology (RSM) was used to develop optimized nanoemulsion formulations. Surfactant content (2~4%), oil content (4~8%) and polyol content (12~24%) were set as independent variables as a result of preliminary experiments for determining independent variables and ranges. The particle size, zeta potential, turbidity, and polydispersity index of the formulation were measured as response variables. As a result of measurement of the prepared nanoemulsion by FIB (Focused ion beam), spherical particles were found to have a size distribution of 100 to 200 nm. The stability of each formulation was evaluated for 30 days at each temperature ($4^{\circ}C$, $25^{\circ}C$, and $45^{\circ}C$). The optimal formulation considering the optimum particle size, turbidity, polydispersity index and zeta potential was found to be surfactant (2%), oil (8%) and polyol (24%).

Block-Quantized 이진 위상 홀로그램을 이용한 효율적인 광학적 perfect shuffle의 구현

김희주,허현,반재경,Kim, Hee-Ju,Huh, Hyun,Pan, Jae-Kyung 대한전자공학회 1996 전자공학회논문지-A Vol.33 No.5

In this paper, we introduced the BQBPH method for making the grating of high efficiency which was improtant in implementing optical PS. The pattern of graing was obtianed by computer simulations using iterative method, and the diffraction efficeincy of designed grating was about 67% through BPM simulation. The grating was fabricated by laser beam writer, and the diffraction efficiency BPM simulation. The grating was fabricated by laser beam writer, and the diffraction efficiency was 47%. We implemented the optical PS with the grating and showed that optical experimental output patterns were good agreement with PS output patterns and first order was main diffraction order.

‘너’를 통해 드러나는 김수영의 정신적 지향 연구

김희주(Kim, Hee-Joo) 한국문학회 2010 韓國文學論叢 Vol.54 No.-

이 논문은 김수영의 시 속에 자주 등장하는 ‘너’에 대한 의미를 규명하기 위한 것이다. 김수영에 관한 최근의 연구들이 ‘전기의 모더니즘, 후기의 참여시로 양분’하여 그 변모과정을 추적하고 시 전체를 일관하는 정신을 찾고 있으나, 그의 시에는 전기 시와 후기 시와 상관없이 ‘나’에 대한 끊임없는 사유가 존재한다. 그리고 그의 시에는 그 ‘나’에 대당되는‘너’가 자주 시에 등장한다. 이 ‘너’의 존재는 ‘반란성’의 존재로 혹은 ‘불온성’의 존재로 드러나기 도 하지만 결국에는 현대사회에서의 김수영 ‘개인’의 운명과 체험에서 드러나는 존재들이다. 현실과 이상 사이의 모순이 클수록, 그 모순의 수용을 드러내는 개인의 내면은 정체성의 분열을 초래할 수밖에 없다. 그 분열의 극복을 김수영은 개인과 개인과의 속박을 통해 주로 드러내는데,이 ‘너’의 모습은 비판의식을 결여한 채 형식주의에 빠져 있던 한국 모더니즘의 한계의 한 면을 드러내고 있다. 현실은 ‘나’와 ‘너’의 통합된 일치없이 존재가 불가능하다. ‘너’를 통해 시인은 현실을 비판하고 자아를 돌아보고 옹호하며, 세계와 연계하여 타협의 실마리를 찾는다. 그러므로 ‘너’의 존재는 시인의 삶에서 소통의 문제라기보다 존재자체의 문제이다. 김수영의 초기 시 <공자의 생활난>에서 대응되는 ‘너’와 ‘나’는 상실 되어가는 자아의 정신지향 면모를 가장 잘 보여주고 있다. 그가 주는 시선의 지점에 놓여 있는 대상 ‘너’는 그의 정신적 의지를 어떤 형상의 지점에 가도록 사유케 하는 ‘너’이다. 이와 더불어 <토끼>와 <달나라의 장난> 또한 자아가 추구해야 하는 무한한 과제와 그 의지를 긴밀하게 ‘너’를 통하여 연결해주고 있다. ‘너’로 호출된 토끼는 현실의 무분별한 수용을 거부하고, 주체성을 지닌 자아로서 존재하려는 시인의 열망을 강화하 는 대상이 되며 ‘팽이’도 이와 같은 맥락으로 존재한다. <풍뎅이>에서는 현실에서 타협하려는 ‘나’와, 내면에 극복의지를 가지고 있는 ‘너’가 함께 일치되기를 간절히 소망하는 ‘또 다른 자아’로서의‘너’가 호출된다. 앞에서 전개된 ‘너’가 ‘나’를 사유케 하고 나의 정신적 지향을 강화시켜주는 ‘너’로 호출된다면, 여기서의 ‘너’는 ‘투영된 자아’로서 호출된다. ‘나’ 와 ‘또 다른 나’의 통합이 서로 긴밀하게 연결될 때 나의 의지는 결국 극복의 맥락으로 넘어간다. 여기서 ‘너’의 호출은 ‘나’의 의지를 강화하기위한 매개물이라기보다 나의 의지를 더 드러내게 하려 는 맥락으로 호출되었다. <너를 잃고>에서의 ‘너’를 찾으려는 시도 또한 결국은 ‘나’를 찾으려는 의도이며, <더러운 향로> 또한 ‘너’인 향로와 ‘나’는 함께 일치되려는 강한 의지를 표출하는데 이 둘의 일치가 결국 현실을 함께 견디고자 하는 강한 의지를 드러내는 지점이라고 할 수 있다. 당대 급변하는 현실을 ‘너’라는 매개물을 통하여 시인의 시선을 의미있게 바라보고, 그 시적 매개체인 ‘너’를 통하여 작가의 내면세계를 접근해 보는 것은 김 수영시의 연구영역을 더 확장하는데 의미 있는 일이다. This research article is to find the meaning of ‘you’ which is often shown in the poem of Kim, Soo-Young. Although the current research on his is classified into modernism of the earlier part, and participating poem of the later part chasing the procedure of changing and looking for spirit which encompassing the whole poem, this is endless personal investigation about ‘self’ in his poem whether it is earlier poem or later poem. Moreover, there exists ‘you’ which refers to ‘self’. This ‘you’ is revealed as the existence of the ‘rebellion’ or the ‘incompleteness’, but the existence of ‘you’ is eventually revealed from his destiny and experience in the modern society. As the the gap between reality and ideal is getting larger, the inside of his disclosing the admission of consistency should result in the dissolution of his identity. Kim, Soo-Young often reveals the overcoming the dissolution through the individual and restriction of the individual the feature of which is disclosing an aspect of the limit of Korean modernism which has been confined to formalism lacking in criticism. It is impossible to exist without the integration of you and self in reality. Poets try to find the clues for negotiation by the connection to the world criticizing the reality, inspecting and advocating the self. Therefore, the existence of ‘you’ is concerned with the existence itself, not with the communication in the poet's life. The self corresponding to ‘you’ in <A struggle against hard life of Confucius>, one of his early poet shows disappearing of spirit of the self. The ‘you’ on one point of his view he gives is the ‘you’ who makes it possible to reach a point of the shape pursuing his spiritual will. <A beetle> failed to get attention compared with the above mentioned <A struggle against hard life of Confucius> despite of extensive research on his poem. Self in this poem is looking at ‘you’ which is the self inside. ‘You’ with the intension to overcome inside, which is separated from the self desire to be integrated. He expresses the intension to overcome his spirit using the ‘shadow’ in a strong tone. This is the affection to his ‘self’. he shows that ‘you’ and self will be integrated as one by way of ‘you’. He takes ‘shadow’ as another poetic self and shows that the separation is a process to proceed to complete oneness. He puts an emphasis on how strong his will to overcome himself by figuring the shadow, the ‘you’ which is inseparable existence. It is meaningful to look at the view of the poet seriously and to perform expansive study what the reality visualized through ‘you’ and what the his spiritual resolution was.