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.

압축력을 받는 결함이 있는 구조물의 주파수 해석

姜贊泳,柳擇仁,朴鳳賢,李晟熙,韓秉基 弘益大學校 科學技術硏究所 1998 科學技術硏究論文集 Vol.9 No.1

Vibration analysis of through-the-width-split beams for predicting buckling load is investigated based on Euler-Bernoulli beam theory. In split region, each segment is considered as a solid beam. In this region, recurrence equations relating integration constants for adjacent interior regions are established by satisfying continuity conditions at junctions of interior regions. The results of present study are compared with those of experiment and their results give good agreement with each other. From the result, it was shown that local buckling phenomena could appear in fundamental mode, however, there exists load carrying capacity after this phenomena.

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.

敎養課程으로서의 「人口와 未來」開設 및 運營에 관한 實驗硏究 : 梨花女子大學校를 中心으로

康宇哲,徐洸善,田贊和,金在恩,蘇興烈 이화여자대학교 한국문화연구원 1979 韓國文化硏究院 論叢 Vol.33 No.-

This is a research report of the research that led to the opening of a population education course at Ewha Womans University. The research itself may be divided into the following four parts: planning for the research ; preparatory work for a population education course; opening of a population course; and evaluation of the population course. In the first stage of the research, the work, as usual, consisted of organizing the research team, setting up the research objectives, planning the research schedule, etc. The project began in the Fall of 1974, and concluded in the Fall of 1978. In the second stage of the research, the work was carried out for the preparation of a course in population education. Several sessions of faculty conference, in which more than 40 professors from various fields of specialization participated, were held in order to determine the specific objectives of the proposed course, to draw up a syllabus, and to prepare for a textbook for the course. When a rough sketch of the syllabus, and the contents of the course was made a student group was organized to examine and evaluate it. In the third stage of the research, a population education course titled "Population and Future" was opened as an elective course in the general education curriculum. This was in the Fall of 1875, and the course remained open every semester until now. An anthology with the same title as the course itself was used for reading, and the teaching was carried out as a team teaching by a team of 6-9 professors. In the fourth stage of the research, an evaluative study was taken up in order to evaluate the course with regard to its structure, textbook, teaching method, and its contents, as well as to assess the effectiveness of the course on terms of the students' change in their cognitive and emotive or attitudinal response to population problem.

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 物理化學硏究所 1984 硏究論文集 Vol.5 No.-

The Li(p, ^4He)^4He reaction is used for in searches of universal abundance of Li, nuclear energy states of ^8Be, and the 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 on 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.

TDI계 수분산성 폴리우레탄 접착제의 특성에 Diisocyanate의 구조가 미치는 영향

강승구,송봉근,이재흥,박찬조,류해일 한국공업화학회 2003 공업화학 Vol.14 No.3

수년 전부터 많은 연구자들에 의해 폴리우레탄의 수용화, 수분산화의 연구가 수행되어 왔다. 그럼에도 불구하고 폴리우레탄의 특성에 디이소시아네이트가 구조에 미치는 영향에 대한 연구는 많이 진행되지 않았고 또한 미흡한 상태이다. 따라서 번 연구에서는 디이소시아네이트의 형태와 함량 변화에 따른 폴리우레탄의 특성을 연구하였다. 폴리우레1탄 수분산체(PUD)는 poly(tetramethylent ether) glycol (PTMG), isophorone diisocyanate (IPDI), toluene 2,4-diisocyanate (TDI), dimethylol propionic acid (DMPA), trethylamine (TEA) 등을 사용하여 제조하였다. 제조한 폴리우레탄 수분산체(PUD)의 구조를 FT-IR을 이용하여 확인하였다. 폴리우레탄 수분산체의 특성은 DSC, gel permeation chromatography (GPC), particle analyzer, universal testing machine (UTM) 등을 사용하여 측정하였다. 폴리우레탄 수분산체(PHD)에서 입자크기는 IPDI 함량이 증가할수록 작아지는 경향을 나타내었으며, 유리전이온도(Tg)는 IPDI 함량이 증가할수록 조금씩 낮아지는 경향을 나타내었다. 또한, 폴리우레탄 수분산체(PUD)의 접착세기 변화에서는 [NCO]/[OH] 몰비를 1.2로 유지되도록 하면서 합성에 관여하는 [NCO] 양에 해당하는 [TDI]/[IPDI] 몰비를 변화시켜 얻은 폴리우레탄 수분산체의 접착세기는 [TDI][IPDI] 몰비가 50/50일때 좋은 집착세기를 나타내었다. 또한 [NCO]/[OH] 몰비를 1.6으로 일정하게 유지되도록 하고 [TDI]/[IPDI] 몰비를 변화시켜 얻은 폴리우레탄 수분산체의 접착세기는 [TDI]/[IPDI] 몰비가 75/25일 때 좋은 접착세기를 나타내었다. Aqueous polyurethane dispersions (PUD) has been investigated by many researchers for a long time. However, relatively little systematic work has been reported, in detail, on the effect of structure of the diisocyanate on the properties of polyurethane. This work describes the properties of polyurethane in relation to the variation of diisocyanate type and contents. Aqueous polyurethane dispersions (PUD) were prepared from the poly(tetramethylene ether) glycol (PTMG), toluene 2,4-diisocyanate (TDI), isophorone diisocyanate (IPDI), dimethyol propionic acid (DMPA), and triethylamine (TEA). Differential scanning calorimetry (DSC), FT-IR, GPC, universal testing machine (UTM), and particle analyzer were utilized to characterize the physical and mechanical properties of PUD according to diisocyanate type and contents. As the content of IPDI in PUD increased, the particle size decreased. The glass transition temperatures (Tg) of PUT were shifted to a lower temperature as IPDI conent increased. When [NCO]/[OH] mole ratio was 1.2, the adhesion force of PUD shown the best result at [TDI]/[IPDI] mole ratio of 50/50. And, at [NCO]/[OH] mole ratio of 1.2, the adhesion force of PUD was the best when [TDIl/[IPDI] mole ratio was 75/25.

돼지설사 원인균 E. coli의 생육저해에 대한 유산균의 효과

姜國熙,成文喜,方泰瑛,龍球淵,林讚洙 成均館大學校 科學技術硏究所 1985 論文集 Vol.36 No.1

E. coli A_2 diarrhea causing bacteria of pigs was anaerobically inoculated with 10^5/ml into prereduced YS medium (10% reconstituted skim milk+0.1% yeast extract), and then lactic acid bacteria were inoculated with 10^5/ml and 10^7ml into previous inoculated samples of E. coli A_2. Inoculated samples cultured at 37℃, were tested to determine changes in viable numbers of organisms and pH. The experimental results are summerized as follows: 1. In the mixed culture medium of 10^5/ml E. coli A_2 and L. casei YIT9018, E. coli A_2 decreased after 36 hours from incubation. 2. In the mixed culture medium of 10^5/ml E. coli A_2 and L. acidophilus, E. coli A_2 drastically decreased after 24 hours from incubation and was almost disappeared after 72 hours from incubation. 3. In the mixed culture medium of 10^5/ml E. coli A_2 and L. bulgaricus, E. coif A_2 drastically decreased after 24 hours from incubation and was almost disappeared after 72 hours from incubation. 4. In the mixed culture medium of 10^5/ml E. coli A_2 and Str. thermophilus, E. coli A_2 decreased after 12 hours from incubation. 5. When the pH value of the mixed culture, was, 4. 5 below, E. coli A_2 decreased.

水系환경과 淡水魚 분포

강병찬 공주대학교 자원과학연구소 2000 資源科學硏究論文集 Vol.8 No.-

This Study was conducted for two year from March of 1999 to October of 2000. The following are the results of the fresh water fishes distributed along the streams, lakes and reservoirs in the county of Yesan. 1. The average number of fresh water fishes found to inhabit the 12 reservoirs in the district amounts to thirty-nine species. 2. Thirty-nine species, the greatest number of the 12 reservoirs surveyed, are found to inhabit Yedang-ho alone. 3. The sequent order of dominant species is Carassius auratus, Cypirinus carpio L, Zacco Platypus, Misgurnus, Mizopepis Gunther. 4. Gobiobotia macrocephlus Mori, known as the endangered species of our country, are found to inhabit Yedang-ho, Songsuk, and Bangsan Reservoirs.

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.

압력센서의 디지털 인터페이스와 신호처리에 관한 연구

강형구,이종호,안광희,이충호,박찬원 江原大學校 産業技術硏究所 1997 産業技術硏究 Vol.17 No.-

A smart pressure measurement system is described, which provides a precise A/D conversion and is highly suitable for communication with microprocessors. In order to avoid unstable problems of remote pressure sensing we have developed a new interface board which performs the A/D conversion and smart signal processing of the measured pressure data Serial communication software which is based on ASCII code commands is also developed to process initial setup an calibration functions as well as multi-drop communication with PC. The test and evaluation of the proposed system has been shown as having the better performance compared to the other types of existing pressure measuring systems and will give good applications to the industrial use where a highly precision remote sensing is needed.