탄성표면파 PSK-MSK 변환 필터

이동욱,이재경,황금찬,Lee, Dong-Wook,Lee, Jae-Kyong,Whang, Keum-Chan 한국음향학회 1990 韓國音響學會誌 Vol.9 No.2

MSK waveforms are advantageous from the point of view of reduced interchannel interference. MSK waveform, however, is more difficult to generate than PSK due to its complex pulse shape. A SAW filter is ideally suited for generation of MSK waveform because it provides accurate control of the required impulse responese and linear phase at high frequncies. In this paper, an implementation of SAW based PSK-MSK convert filter, which can easily convert the high frequency PSK waveform to MSK, is studied. MSK 신호는 PSK 신호보다 좁은 주파수 대역을 차지하여 채널간 간섭을 줄을 수 있는 장점이 있지만, 고주파 대역에서는 신호를 만들기 어렵다. 본 논문에서는 탄성표면과 필터가 고주파 대역에서도 원하는 임펄스 응답과 선형 위상 특성을 얻기 용이하다는 장점을 이용하여 손쉽게 고주파 PSK 신호를 MSK 신호로 실시간 변환 처리하는 탄성표면과 PSK-MSK 변환 필터를 설계 제작하고 그특성을 고찰하였다.

산·학·연 공동 협업적 원자력 R&D 활성화 - 한국원자력연구원의 산·학·연 협력

이동욱,Lee, Dong-Uk 한국원자력산업회의 2016 원자력산업 Vol.36 No.9

설문지를 통한 소음성난청에 대한 인식 조사 및 분석

이동욱,유재형,한우재,Lee, Donguk,Yu, Jyaehyung,Han, Woojae 한국음향학회 2015 韓國音響學會誌 Vol.34 No.4

소음성난청은 고려 시 되어야 하는 공중보건 문제로 알려져 있지만, 큰 소음의 노출로 인해 난청이 발생됨을 많은 사람들은 잘 인식하지 못하고 있다. 본 연구의 목적은 일반인들이 얼마나 중요하고 심각하게 소음성난청에 대하여 인식하고 있는지 22개의 설문 문항을 바탕으로 조사하고 그 결과를 분석하였다. 20대부터 60대의 성인 남녀 150명을 대상으로 청력손실과 이명을 포함하여 일반적인 건강 문제들에 대한 사회 및 개인적 중요도, 소음노출과 청력손실에 대한 인지 정도, 청력 보존 방법에 대한 인식을 문답하였다. 연구 결과, 다른 건강 문제들과 비교하여 응답자 중 약 17.33 %만이 청력손실을 '매우 큰 문제'로 인식하였다. 놀랍게도 다수의 응답자인 82 %는 청력손실에 관한 정보를 듣거나 보지 못하였다고 답변하였다. 전체 응답자 중 약 85 %의 응답자들은 큰 소음이 있는 환경에서 청력 문제 및 이명을 경험한 적이 있다고 답하였지만, 그 중 11.33 %만이 이어플러그를 착용해 본적이 있다고 응답하였다. 그러나 많은 응답자들은 추후 의료진이 권장하거나(80 %), 소음으로 인한 영구적 청력손실이 발생할 수 있다는 정보를 접한다면(78.67 %) 청력보호를 위해 소음 노출 시 이어플러그를 착용하겠다고 응답하였다. 소음으로 인한 영구적 청력 손실의 잠재성과 효율적인 청력 보호 방법에 대한 체계적인 교육으로 일반인들의 소음성난청을 예방하여야 하겠다. Although noise-induced hearing loss (NIHL) is a significant public health problem, many people might not be aware that exposure to loud noise could occur hearing loss. The purpose of this study is to evaluate and analyze how importantly and seriously people are aware of NIHL using a 22-question survey. It was administered to random 150 people including between 20 s to 60 s. The questionnaire contained questions about i) views toward general health issues including hearing loss and tinnitus, ii) noise exposure, and iii) views toward hearing protection. Results showed that hearing loss was defined on a likert scale as 'a very big problem' by 17.33 % of respondents compared with other health issues. Surprisingly, most respondents (82 %) had not heard, read, or seen anything lately related to the issue of hearing loss. Many respondents had experience hearing problem or tinnitus under loud noise situations (85 %), however, only 11.33 % of respondents had used earplugs. Fortunately, many could be motivated to try ear protection if they were advised by a medical professional (80 %) or were aware of the potential for permeant hearing loss (78.67 %). We concluded that awareness of the potential for permanent hearing loss with noise and effective methods of hearing protection should be announced to public for preventing NIHL.

납착 인기재료가 분할 주조체의 변형에 미치는 영향

이동욱,임장섭,정창모,전영찬,Lee, Dong-Wook,Im, Jang-Seop,Jeong, Chang-Mo,Jeon, Yeong-Chan 대한치과보철학회 2000 대한치과보철학회지 Vol.38 No.1

The purpose of this study was to investigate the effect that three resin indexing materials had on the distortion of split cast in the procedures of solder indexing and block fabrication. The specimen had two cylinders and connecting bar Two cylinders were a reference cylinder and a test cylinder that were machined precisely and placed on metal base. The total of specimens were 30 and they were divided into 3 groups according to the resin indexing materials : Acrylic $solder^{(R)}$, G-C Pattern $resin^{(R)},\;Z-100^{(R)}$. The relative coordinates (X, Y, Z) of centroids of both cylinders were measured by using 3-D cool dinates measuring machine. The value of indexing distortion was obtained after application of indexing material, and the value of the block distortion was obtained after fabrication of soldering block, and the value of total distortion was a value sum of indexing distortion and block distortion. Intercentroidal linear distortion ${(\sqrt{X^{'2}+Y^{'2}+Z^{'2}}-{\sqrt{X^2+Y^2+Z^2)}$ and global distortion $(\sqrt{{(X^'-X)}^2+{(Y^'-Y)}^2+{(Z^'-Z)}^2}$ were calculated from data of coordinates of centroids at each measuring stages. The results of this study were as belows ; 1. The intercentroidal distance between the split casts was reduced by indexing distortion and increased by block distortion. 2. The indexing global distortion between the split casts was smaller than block global distortion. 3. The intercentroidal linear distortion and the global distortion were no significant difference between indexing materials.

고주파 SAW Filter 의 제작과 Filter 특성

이동욱,김동수,강성건,류근걸,남효덕,이만형 ( Dong Uk Lee,Dong Su Kim,Sung Gun Kang,Kun Kul Ryoo,Hyo Duk Nam,Man Hyeong Lee ) 한국전기전자재료학회 1997 한국전기전자재료학회 추계학술대회논문집 Vol.1997 No.1

DNA 코딩방법을 이용한 셀룰라 오토마타 신경망의 진화

이동욱,심귀보,Lee, Dong-Wook,Sim, Kwee-Bo 대한전자공학회 1999 電子工學會論文誌, S Vol.s36 No.12

셀룰라 오토마타 신경망(CANS)은 생물학적 발생과 진화에 기반한 신경망 모델이다. CANS에서 각 뉴런은 상호간에 국소적인 연결을 갖고 있으며 카오스 뉴런 모델의 동작 방정식에 따라 펄스의 형태로 동작한다. 신경망은 초기 패턴을 셀룰라 오토마타(CA) 규칙에 따라 발생시켜 얻어진다. 기존의 연구에서는 유용한 기능을 얻기 위하여 초기패턴을 진화시켰다. 그러나 이 방법은 신경망의 표현공간을 모두 나타낼 수 없다. 따라서 본 논문에서는 신경망의 표현공간이 작아지는 문제점을 개선하기 위한 CA의 발생규칙을 진화시키는 방법을 제안한다. DNA 코딩은 코딩의 중복과 여분을 효과적으로 사용하며 규칙의 표현에 매우 적합하다. 본 논문에서는 CA 규칙의 일반적인 표현방법을 제시하고 DNA 코드를 CA 규칙으로 해석하는 방법을 제안한다. 제안된 방법은 자율이동로봇의 제어기에 사용하여 주행 문제에 적용함으로써 그 유효성을 확인하였다. Cellular Automata Neural Systems(CANS) are neural networks based on biological development and evolution. Each neuron of CANS has local connection and acts as a form of pulse according to the dynamics of the chaotic neuron. CANS are generated from initial cells according to the CA rule. In the previous study, to obtain the useful ability of CANS, we make the pattern of initial cells evolve. However, it is impossible to represent all solution space, so we propose an evolving method of CA rule to overcome this defect in this paper. DNA coding has the redundancy and overlapping of gene and is apt for the representation of the rule. In this paper, we show the general expression of CA rule and propose translation method from DNA code to CA rule. The effectiveness of the proposed scheme was verified by applying it to the navigation problem of autonomous mobile robot.

서울시 아파트단지의 녹지배치 및 식재구조 변화 연구

이동욱,이경재,한봉호,장재훈,김종엽,Lee, Dong-Wook,Lee, Kyong-Jae,Han, Bong-Ho,Jang, Jae-Hoon,Kim, Jong-Yup 한국조경학회 2012 韓國造景學會誌 Vol.40 No.4

본 연구는 서울시 아파트단지의 시기별 녹지배치구조와 식재구조의 변화과정을 분석하여 보다 친환경적인 아파트단지 내 녹지조성 개선방안을 제시하고자 하였다. 연구대상지는 서울시에 조성된 아파트단지 중 조성시기, 용적률, 지하주차장에 의한 지반현황, 녹지율의 차이가 뚜렷한 아파트단지 12개소를 선정하였다. 연구대상지 유형화는 시기별로 녹지율과 지반현황을 기준으로 녹지율이 높은(40% 이상) 자연지반 아파트, 녹지율이 낮은(40% 미만) 자연지반 아파트, 녹지율이 낮은(40% 미만) 인공지반 아파트, 녹지율이 높은(40% 이상) 인공지반 아파트 네 가지로 구분하였다. 아파트단지 녹지배치 구조의 가장 근원적 변화요인은 녹지율과 인공지반 여부로 용적률이 상승하면서 주차장 면적비율도 높아져 상대적으로 녹지율은 낮아졌다. 녹지배치구조가 가장 많이 변한 녹지유형은 전면녹지와 완충녹지로 전면녹지는 녹지율이 높은 자연지반 아파트의 평균 녹지 폭 10.0m에서 3.5m, 2.7m, 4.5m로 시기별로 축소 변화하였다. 완충녹지는 녹지율이 높은 자연지반 아파트에서 평균 녹지 폭 15.0m로 단지외곽 경계부를 연결하였으나, 녹지율이 낮은 인공지반 아파트에서 주차장 확대로 평균 녹지 폭이 7.7m, 2.7m로 점차 축소되고 일부 구간은 단절되었으나, 2001년 이후 녹지에 대한 인식변화로 다시 평균 녹지 폭이 3.8m로 넓어지면서 연결되었다. 녹량 변화를 살펴보면, 녹지율이 높은 자연지반 아파트 녹지용적계수가 $1.27m^3/m^2$이었고, 식재밀도가 높아지면서 녹지율이 낮은 자연지반 아파트의 녹지용적계수가 $3.47m^3/m^2$로 가장 높았다. 반면에 녹지율이 높은 인공지반 아파트의 녹지용적계수는 $0.72m^3/m^2$로 매우 낮은 상태이었다. 식재밀도는 교목 아교목층의 경우 5.0주/$100m^2$에서 14.5주/$100m^2$로 증가하였다. 아파트단지 녹지를 보다 친환경적이고 기능적으로 조성하기 위한 방안으로 녹지율 40% 이상의 아파트단지 내 전면녹지는 녹지 폭 4.5m 이상으로 확대하여 정원개념의 경관 식재지로 조성하고, 후면녹지는 녹지 폭 5.0m이상으로 확대하고 복층구조로 식재하여 녹지량을 증진하는 것을 제시하였다. 측면녹지는 수고가 높은 수종을 식재하여 벽면 차폐와 녹음기능을 증진하고, 완충녹지는 자생수종을 자연림에 가까운 다층구조로 조성하는 생태적 배식기법을 적용하면서 단지내부녹지와 연결해야 할 것으로 판단되었다. This study was carried out to propose the improved method by analyzing the change of green space arrangement and planting structure of apartment complexes in Seoul. 12 survey sites, which have obvious differences, were selected by reflecting the change of floor area ratio, underground parking place, and green space ratio. We divided the survey sites into four types that high green ratio(over 40%) apartment on natural ground, low green ratio(under 40%) apartment on natural ground, low green ratio(under 40%) apartment on artificial ground, and high green ratio(over 40%) apartment on artificial ground each period based on green space ratio and ground structure, plant crown volume, planting density, and planting pattern. The main factors of change of green space arrangement were green space ratio and ground structure. The Green space ratio was changed by the floor area ratio with constructing underground parking place and floor area ratio was adjusted by government policy and economic status. Average width of front green area has been changed from 10.0m in high green ratio apartment on natural ground for 3.5m, 2.7m, and 4.5m each period. The average width of the buffer green area has been changed from 15.0m in high green ratio apartment on natural ground of 7.7m, and 2.7m by extending parking place in the low green ratio apartment of artificial ground, so buffer green areas have been reduced and disconnected. So buffer green area in apartment complexes has been extended that the average width of the buffer green area was 3.8m caused by growing recognition of green since 2001. The ratio of native plant in canopy layer was increased from 45.1 % in the case of the high green ratio apartment of natural ground in 1980~1983 to 55.6%. Average plant crown volume increased from $1.27m^3/m^2$ in high green ratio apartment on natural ground for $3.47m^3/m^2$ in a low green ratio apartment on natural ground. But average plant crown volume is $0.27m^3/m^2$ in the high green ratio apartment of the artificial ground plant density of canopy layer was changed from 5 individuals per $100m^2$ to 14.5 individuals per $100m^2$. We should construct the buffer green area with natural ground and get the function of ecological and beautiful environment regarding to garden concept in case of front green area, width 4.5m. We should get the function of increasing green volume by multi-layer planting with shade woody species and flower woody species in case of back-side green area, width over 5.0m. We should get the function of covering the wall and increasing green landscape by planting with high woody species in case of side green area. We should apply the ecological planting technique to buffer green area and connect buffer green area to inner green area in apartment complexes.

흰쥐 간 마이크로좀의 cytochrome P - 450 의존성 testosterone hydroxylase 의 활성도 측정

이동욱,박기현 ( Dong Wook Lee,Ki Hyun Park ) 생화학분자생물학회 1988 BMB Reports Vol.21 No.3

A rapid and one time determinable TLC method for the monohydroxytestosterones formed by microsomal cytochrome P-450(P-450) was established, and applying this method the activity of P-450-dependent testosterone hydroxylases was observed in liver microsomes of rats pretreated with phenobarbital(PB). The 14 testosterone metabolites were found on the TLC plate. The amounts of 6-monohydroxytestosterones (2α-, 2β-, 6α-, 6β-,7α-and 16α-OH-T) were determined. The formation of these metabolites showed a good linearity(r = 0.9687-0.9999) corresponding to the concentration of P-450 added up to about 1.0 nmol/min/reaction mixture, and an excellent reproducibility (C.V.= 1.8 ± 1.0%) when determined with 0.5 nmol P-450 in this assay system. The hydroxylation of testosterone to its 2β-OH-T by PB-inducible P-450 was increased (2 fold), while 2α- and 7α-OH-T was rather decreased to 48 and 32%, respectively, compared with those of uninduced one. The 6β-OH-T was predominantly formed by uninducible and PB-inducible P-450, especially PB-inducible P-450 hydroxylated stereospecifically onto the C2-position of testosterone (2α/2β =1: 3.8). However, the oxidation rates of testosterone to its 6α-, 6β- and 16α-OH-T, and the total amount of testosterone metabolites identified were not changed, significantly by the administration of PB.

Citrate Process를 이용한 BaCeO₃ 나노 분말의 저온 합성

이동욱,원종한,주경,김창열,심광보,Lee, Dong-Wook,Won, Jong-Han,Joo, Kyoung,Kim, Chang-Yeoul,Shim, Kwang-Bo 한국세라믹학회 2002 한국세라믹학회지 Vol.39 No.6

Nanosized $BaCeO_3$ powders with the stoichiometric composition of a molecular level were synthesized by the citrate process based on the Pechini method. Polymeric precursor was formed by use of citric acid and ethylen glycol, as chelating agent of metal ions and reaction medium, respectively. Single phase orthorhombic structured $BaCeO_3$powders, about 100 nm sized and uniform shaped were obtained through the calcination of the polymeric precursor at $900^{\circ}C$ for 4 h. Extremely small quantities of carbonate ions($CO_^{2-}$) were completely decomposed at over $1100^{\circ}C$. The mean size of the powders was increased twice, however, it has very uniform distribution in its size and shape. 분자 단위의 균일한 조성을 가지는 $BaCeO_3$ 나노 분말을 Pechini법에 기초한 citrate 공정을 통하여 합성하였다. 금속 이온의 chelating제로서 citric acid를, 반응 촉매로서는 ethylen glycol을 각각 사용하여 고분자 전구체를 형성시켰고, 이를 기반으로 $900^{\circ}C$의 온도에서 4시간동안 열처리하여 약 100nm의 균일한 크기와 형상을 가진, 사방정 구조의 단일상 $BaCeO_3$ 분말을 합성하는데 성공하였다. 잔존하는 미량의 $CO_3^{2-}$는 $1100^{\circ}C$ 이상의 온도에서 완전히 분해되었고, 이 때 평균 입도 는 약 2배 증가하였으나 매우 균일한 분포를 나타내었다.

교과교실제 운영에 따른 공간구성 변화에 대한 현황분석 - 리모델링된 10개 고등학교의 사례 -

이동욱,류호섭,Lee, Dong-Wook,Rieu, Ho-Seoup 한국교육시설학회 2012 敎育施設 Vol.19 No.1

Recently, many middle and high schools are remodeling the buildings and facilities based on departmental system. This study, through analyzing on 10 remodeling cases of high school, is showing the variation before and after remodeling, space organization types, and the types of school management. This also gives us the information on the number of classrooms and teachers' rooms for each subject, the area and number of home base, and the current state of all these facilities. Furthermore, this study is comparing and analyzing the rate of use of specialized classrooms to the type of management. Through this analysis, we reach the following conclusions. l. However all the cases remodeled their buildings to implement departmental system, the methods of space composition, the numbers of the classrooms, and the status of home base are in various forms. 2. Taken as a whole, there are only few spaces used by departmental system. 3. The spaces for practical subjects such as Science and Art are inadequate than the ones for major subjects such as Languages and Mathematics. 4. A system to assign a room for a teacher records the lowest space usage rate. 5. The area of home base per one student is only $0.48m^2$, and even the area is mostly filled with lockers. The present condition of the 10 high schools which we surveyed shortly after remodeled shows that departmental system is not firmly settled down yet.