전력선 채널에서의 DS/SSMA BPSK 코릴레이션 수신기 성능에 관한 연구

강병권,조창길,조관,이재경,황금찬,Kang, Byeong-Kwon,Cho, Chang-Gil,Cho, Kwan,Lee, Jae-Kyeong,Whang, Keum-Chan 한국통신학회 1992 韓國通信學會論文誌 Vol.17 No.9

본 논문에서는 전력선 채널에서 DS/SSMA BPSK 통신 시스템의 전형 및 하드리미팅 상관 수신기의 성능을 분석하였다. Chan의 잡음 모델을 이용하여 전력전에서 발생하는 강한 임펄스성 잡음을 배경 잡음에 대한 임펄스성 잡음의 전력 스펙트럼 밀도비 $(N_1/N_b)$, 데이터 폭에 대한 임펄스성 잡음 폭의 비(f). 임펄스성 잡음의 발생주기에 대한 임펄스 잡음 폭 (DF)등의 파라미터로 모델링하여, 각 파라미터 변화에 따른 시스템의 성능을 분석하고, 다중접속 간섭 잡음을 가우시안 근사화하여 각 수신기의 다중접속 능력을 평가하였다. 분석 결과 $N_1/N_b$가 작고 f가 1에 가까운 경우 전형 상관 수신기의 성능이 더 우수했으나, $N_1/N_b$가 증가함에 따라 하드리미팅 상관 수신기가 비트 오율 및 다중 접속 능력면에서 전형 상관 수신기보다 더 우수한 성능을 나타냈다. In this paper, the performance of linear and hard-limiting correlation receivers for DS/SSMA BPSK power line communication system is analyzed. Strong impulsive noise of power line is modeled with Chan's noise model, and the performance of both receivers is analyzed in terms of parameters such as ratio of power spectrum density of impulsive noise to that background noise, ratio in impulsive noise width th that of data bit, and interarrival time of impulsive noise. And also multiple access capacity is evaluated with Gaussian approximation of multiple access interference. The results of this analysis reveal that the performance of linear correlation receiver is superior to that of hard-limiting correlation receiver when $N_1/N_b$ is small and is close to 1. But the BER and the multiple access capacity of hard-limiting correlation receiver becomes better in comparison with linear correlation receiver as $N_1/N_b$ increases.

Pd(O)-촉매를 이용한 알릴 고리 카보네이트의 제거 및 분자간 축합반응 연구

강석구,박동철,박찬희,홍륭기 성균관대학교 기초과학연구소 1995 論文集 Vol.46 No.1

The alkyl substituted allylic cyclic carbonates 1a-d undergo elimination by using a catalytic amount of Pd(0) complex to form dienols 2 a-b. However, on treatment of the unsubstituted or phenyl substituted allylic cyclic carbonates 1e and 1f with Palladium(0) catalyst, deprotonation-elimination of π-allyl Palladium complex followed by condensation with the other π-allyl Palladium complex provided the coupled products 3a and 3b, respectively.

Pd 촉매 하에서 알릴 디올의 아릴화 연구 : 방향족 히드록시 케톤 및 페닐 치환된 알릴디올의 합성 Highly Selective Synthesis of Phenyl-Substituted Allylic Diols

강석구,정경윤,박찬희,남궁은영,김태현 성균관대학교 기초과학연구소 1995 論文集 Vol.46 No.2

The coupling reaction of iodobenzene with allylic diols in the presence of Pd(OAc)_2 and nBu_3P as catalysts using K_2CO_3 as base afforded the phenyl-substituted allylic diols. However, under the same reaction conditions with Et3N as base, phenyl-substituted α-hydroxy ketone was obtained.

Back-Propagation Algorithm 상에서의 성능에 미치는 Parameters 분석에 관한 연구

강수연,박찬호,이현수 慶熙大學校 1994 論文集 Vol.23 No.-

신경망에서 가장 많이 사용되고 있는 알고리즘 중의 하나가 역전파(Back-Propagation) 알고리즘이다. 역전파 알고리즘에서 문제해결에 본질적인 영향을 주는 몇가지 요인들이 존재한다. 본 연구에서는 이 몇가지 요인들이 각각의 응용 문제의 해를 얻는데 미치는 영향을 시뮬레이션 결과를 통해 알아보고 이를 분석및 고찰 하였다. 고려 대상의 요인들로써는 learning rate, momentum, weight 초기값, 은닉 유니트수를 들 수 있다. 응용 문제 대상은 XOR 문제와 8*8 dot alphanumeric font 학습으로 하였다. Back-Propagation is one of algorithms that are currently used in neural network. It has some factors that basically affect on solving problems. On this paper, we analyze and investigate several learning parameters that effect on solutions of each application problems through simulation result. Considered factors are learning rate, momentum, initial weight values and the number of hidden units. Applied problems are XOR learning and 8*8 dot alphanumeric font learning.

CR-39 플라스틱飛跡檢出器에 의한 ^7Li(p, ^4He)^4He 核反應의 斷面積 測定

姜榮浩,安燦基,金道聖 慶北大學校 1984 論文集 Vol.37 No.-

The ^7Li(p,^4He)^4He reaction is used for in searches of universal abundance of Li, nuclear energy stages of ^8Be, and final step of p-p fusion cycle. In this work, we have detected and identified ^3He and ^4He from the ^6Li(p,^3He)^4He reaction and ^4He from the ^7Li(p,^4He)^4He reaction by the energy dependence of the etch pit diameter of the chemically etched tracks in CR-39. The target was 12㎍/㎠ thin film of natural lithium evaporated in the 10㎛/㎠ carbon backing. The target thickness was measured by Rutherford scattering of proton particles. For proton energies between 148keV and 462keV, differential cross section, angular distribution, and total cross section were measured. The results were compared with the previous measurements and Gamow-Diagram.

유기산 완충용액의 포화도가 상아질의 탈회에 미치는 영향

강혜실,이찬영 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.5

The purpose of this study is to compare and to evaluate the effects of the degree of saturation on the progression of artificial root caries lesion. A total of 8 human premolars without any defects and cracks selected and the cementum were removed and the teeth were cleaned with ultrasonic device and pumice without fluoride. Each tooth was sectioned into 6 pieces and they were ground with #800 sandpaper until they had a thickness of 200 ㎛. Specimens were applied with nail vanish except for the 2-3 mm window area after application of bonding agent. Under the constant pH, the specimens were divided into 6 groups (degree of saturation: 0.1415, 0.1503, 0.1597, 0.1676, 0.1771. 0.1977). Each group was immersed in acid buffer solution for 1, 2, 3, 5 days under controlled temperature (25℃) and imbibed in water and examined using the polarizing microscope. The results were as follows 1. Although the degree of saturation of demineralization solution decreased, the depth of penetration in the dentin was constant. 2. Erosion was observed on the surface of all the teeth in the group Ⅰ, Ⅱ. In the group Ⅲ, Ⅳ, Ⅴ, surfaces were not changed. The teeth in the group Ⅵ showed the more mineralized surface but not the shape of the dentinal tubules distinctively. 3. In all groups, the lesion progressed rapidly at the first day of the experiment, but increased gradually as time elapsed.

生物膜 ?過裝置에 의한 下水處理에 관한 硏究

姜龍太,全裕燦,趙奉衍 東亞大學校 1986 東亞論叢 Vol.23 No.1

This study, through the filtration experiment by biofilm, was explained the operation for each processes in its system, and were investigated the actual(filtration experiment by biofilm) applicational propriety for the existing headloss quation and the correlation of factors. The results of the experiment are the following. 1. When the raw water quality was reached to standars of the treated water quality in about a week, the average removal rates of SS, BOD and COD were 92%, 91% and 74%, respectively. 2. In case that the experimental conditions were water quantity, 0.67㎥/day, BOD 100㎎/ℓ, oxygen absorption efficiency, 16%, air quantity was 15N㎥ and showed high BOD removal rate. 3. The backwashing water quantity was required the twice or the three times of the packed volume. 4. When thd BOD loading was less then 5 ㎏/㎥·day, the BOD removal rate showed more than 95%. 5. The headloss of this experiment was approximated to the value obtained from substiting the filtration Model Ⅰ for the Kang's headloss equation corrected for the Kozeny-Carman's.

스키선수의 체력수준이 경기성적에 미치는 영향

康燦金 단국대학교 1995 論文集 Vol.29 No.-

A study on the effect of anaerobic threshold level of skier(Nordic) to the game record has been performed and concluded as follows 1. Comparing domestic long-distance skier to foreign superiors, a wide difference in maximum oxygen uptake has been found to be 8㎖/㎏·min and 16.3㎖/㎏·min for male and female respectively. 2. Comparing domestic long-distance skier to foreign superiors, anaerobic threshold level has been found to be 10-20% and 8-13% lower for male and female respectively. 3. Anaerobic threshold lever, the index represent sporting ability with nere meximum oxygen uptake and simultanously without accumulation of mamary acid for a long time should be promoted to get a letter record.

空氣拳銃 擊發時 心拍數 變化에 관한 硏究

康燦金 단국대학교 1986 論文集 Vol.20 No.-

The result of investigation into the variation of the number of heart beating. The score rate by points and the point of impact by the position at firing an air rifle for the male shooter of B high school in Seoul has come out as the following. 1. The comparison of the score rate by points. In the a group. There were three who scored more than 20% from the total points 600.In the B group, on the other hand, there was only one. The rate of high gore in an average was in the A group that has many long experienced shooter, and of low score was in the B group. 2. The comparison of the point of inpact by the position. The shooters from A group K.K. N.,L.S.S., made 20%, 25.4% in the direction of 6~7o'clock, P.K.H.l8.3% in 4~5 0'clcrk, L.J.Y.21.7% in 7~8. From the B group, on the other hand, in the same direction of 7~8, K.M.H., H.S.W., K.S.K. made the same direction with 18.6,18.3,23.3%.The reason of uneven formation of the point of impact is the work of the individualities of the shooters. 3. The variation of the number of heart-beating at firing by the score, P.K.M. from the A group had faster heart beating while he was gaining in high score, others' heart beating, on the other hand were irregular. The reason can be interpreted as the shooters were selected without consideration for the synthetic aptitude.

단음절 합성단위음을 사용한 시간영역에서의 한국어 연속음 규칙합성에 관한 연구

강찬희,안영화 江南大學校産學技術硏究所 2004 산학기술연구소논문집 Vol.- No.18

본 논문은 시간영역에서의 한국어 연속음 규칙합성에 관한 실험적 연구결과이다. 특히, 단음절 단위음을 사용하여 연속음을 합성할 경우 음절간의 피치 불연속성으로 인한 자연성 및 음질이 저하되는 현상을 개선하고자 하였다. 이를 위하여 자연음으로부터 추출한 구문 단위의 피치 패턴을 보간법으로 생성시켜 합성하는 방법을 제안하였다. 중심주파수가 80, 118, 140, 170, 200Hz인 5가지 유형의 피치 패턴을 2음절어 및 3음절어에 각각 부여하여 합성시킨 합성음에 대한 MOS평가를 수행한 결과를 제시하였다. 실험결과, 제안한 시간영역에서의 합성방식에 의한 합성음의 음질은 명료하고 자연스러웠으며, 간단한 문장단위의 연속음 합성이 가능하였다. 운율요소의 제어결과는 지속시간(장단)과 악센트(강약)와 피치주기(억양) 및 에너지 패턴의 제어도 시간영역에서 가능하였다.