xDSL을 위한 오류 제어 시스템 모델링 및 성능평가에 관한 연구

권호열,전진화 강원대학교 정보통신연구소 1999 정보통신논문지 Vol.3 No.-

In the xDSL channel of the twisted pair line, there are long burst errors because of impulse noise such as NEXT(Near end crosstalk), RFI(Radio frequency interference). So if only error control code were used for burst error correction, error control system is very complex. Therefore if an interleaver that distributes burst errors to a few codewords were used with error control code, a total error control system performance is promoted. In this paper, Reed-Solomon code used for correcting these burst errors, and scrambler, sequential interleaver. The channel loss is impulse noise tested for the ANSI T1E1.4. And a total system is simulated at the matlab communication and simulink toolbox. An analysis evaluation is acquired to error rate of the error correct system, and delay time of the interleaver, interleaver efficience.

52 Mbps급 CAP 전송시스템의 모델링과 성능분석

권호열,전진화,김범규 강원대학교 정보통신연구소 1998 정보통신논문지 Vol.2 No.-

Carrierless Amplitude Modulation/Phase Modulation(CAP) has the same spectral characteristics and provides the same theoretical performance as QAM, but is generally less complex to implement digitally. In this paper, a 52 Mbps CAP transceiver system is modeled and simulated according to DAVIC VDSL standard. Also we analyzed error rate characteristics under AWGN channel by using MATLAB.

Fe-27.5 at.% Al 금속간 화합물의 변형거동에 미치는 변형율 속도의 영향

송진화,하태권,장영원 대한금속재료학회 2004 대한금속·재료학회지 Vol.42 No.11

The effect of strain rate on the room temperature deformation behavior of a Fe-27.5 at.% Al has been investigated in this study. Phase composition and degree of order in Fe-27.5 at.% Al alloy were varied by aging at various temperatures corresponding to phase fields of D03 and B2 to elucidate the effects of microstructure and degree of order on the room temperature deformation behavior. A series of load relaxation tests was conducted and the results were analyzed based on the internal variable theory of inelastic deformation. Room temperature strength of the Fe-27.5 at.% Al alloy was found to increase with decrease in degree of order. All the flow curves could be successfully described by the constitutive equations of the internal variable theory of inelastic deformation and were found to be governed by the frictional stress element. (Received June 20, 2004)

운동분류에 따른 체구성 성분 및 BMI의 비교

최명화,권영우,김진해,민경선,민진아 한국스포츠리서치 2001 한국 스포츠 리서치 Vol.12 No.4

The purpose of the present was to investigate the body composition and BMI in different sports groups with classification of sports. 121 male collegiate athletes were recruited from varsity team of golf(n=10), field hokey(n=18), tennis(n=8), judo(n=17), weight lifting(n=27), boxing(n=19) and bicycle(n=22). Sports event can be classified as low static/low dynamic such as golf(LSLD), low static/high dynamic such as hokey and tennis(LSHD), high static/low dynamic such as judo and weight lifting(HSLD), high static/high dynamic(HSHD) such as boxing and bicycle. With classification of sports events, percentage of body fat was significantly higher with HSLD group compared to HSHD group, but no measurable difference was LSLD and LSHD groups. LBM was significantly greater with HSLD group compared to LSHD and HSHD groups. Furthermore BMI of the HSLD group was higher than the other groups(p<.05). In conclusion, high static/low dynamic group were greater in %fat, LBM, BMI than other groups. The differences observed between different sports groups and classification of sports are related to metabolic and dynamic properties in different sports events.

생물학 탐구에서 학생들이 생성한 가설검증방법의 유형

박순화,고경태,정진수,권용주 한국과학교육학회 2005 한국과학교육학회지 Vol.25 No.2

이 연구의 목적은 학생들의 생물학 가설검증방법의 유형을 분류 데 있다. 이를 위해 고등학생 35명과 대학생 40명을 표집 하여 수국, 제비 나비, 감자즙, 펭귄 등 4개의 가설검증 과제를 투입하였다. 각 과제에서 연구대상 학생들은 현상을 관찰하여 인과적 의문을 생성하고, 집단토의를 통해서 하나의 가설을 생성하였다. 그런 후 스스로 생성한 가설을 검증할 수 있는 방법을 고안하였다. 연구자들은 이렇게 고안된 학생들의 가설검증방법을 분석하여 몇 가지로 유형화하였다 그 결과에 의하면 먼저, 하나의 원인으로 된 가설의 검증유형은 직접 관찰법, 유사현상 비교법, 긍정 비교법, 긍정-부정 비교법, 비례 비교법 등으로 분류되었다 그리고 여러 개의 원인으로 된 가설은 크게 부분 검증법과 전체 검증법으로 구분되었고, 부분 검증법은 다시 단일 유형과 다수 유형의 하위 유형으로 구분되었으며, 전체 검증법은 유기적 유형, 기계적 유형, 혼합 유형 등의 하위 유형으로 구분되었다. The purpose of this study was to analyze the college students' and high school students' testing methods for biological hypotheses. Subjects were 35 11th grade students and 40 college students. Four hypothesis-testing tasks were developed and administered to the subjects: hydrangea, swallow butterfly, juiced potato, and penguin tasks. After being presented with the phenomena of the tasks, students were asked to generate questions and hypotheses and then to write a hypothesis-testing method on a questionnaire. Students' hypothesis-testing methods were classified into 5 types for mono-cause hypotheses; direct observation, similar phenomenon comparison, positive comparison, positive-negative comparison, and proportion comparison. In addition, students' hypothesis-testing methods were classified into 5 types for multi-cause hypotheses; mono type, poly type, organic type, mechanic type, and mixed type. This study also discussed the implications of these findings for teaching and learning in science education.

국내 사용 농약을 대상으로 한 HPLC 방법에 의한 옥탄올/물 분배계수 추정법의 적용성 검토

김균,권진욱,김용화 한국환경독성학회 2001 환경독성보건학회지 Vol.16 No.4

Octanol/water partition coefficients of 52 chemicals were calculated using RP-HPLC estimation method and predicted by computer program, PCHEM, The result showed relationship between literature values and RP-HPLC observed values (relative coefficient r² = 0.916), but the relationship of PCHEM values with literature values was lower than RP-HPLC value (relative coefficient r² = 0.795). The average difference in partition coefficient between the RP-HPLC method and flask-shaking method was log Kow=0.54, while the average difference between the values predicted form the computer program and flask-shaking method was log Kew = 0.36. Compared to octanol/water partition coefficients by 3 methods (Flask-shaking, RP-HPLC, computer prediction), the octanol/water partition coefficient values based on the flask-shaking method were very similar to the literature values, while the octanol/water partition coefficient values by RP-HPLC method without to consider the dead time, and computer prediction values did not significantly differ with the literature values.

Fe-24 at.% Al 금속간 화합물의 상온 변형 거동

河泰權,宋辰華,張榮遠 대한금속재료학회 2002 대한금속·재료학회지 Vol.40 No.8

Room temperature deformation behavior of a Fe-base intermetallic alloy with the composition of Fe-24 at.% Al has been investigated in this study. Phase composition and degree of order in Fe-24 at.% Al alloy were varied by aging at temperatures corresponding to the various phase fields of DO_3, α+DO_3, α+B2, and B2 to elucidate the effects of microstructure and degree of order on the room temperature deformation behavior. Load relaxation tests were conducted at room temperature and the results were analyzed based on the internal variable theory of inelastic deformation. Room temperature strength of the Fe-24 at.% Al alloy appeared to increase with decreasing degree of order and the hardening effect of disordered α precipitation was found to depend on the shape. All flow curves could be successfully described by the constitutive equations of the internal variable theory and the strain rate sensitivities of the Fe-24 at.% Al alloy at room temperature were very small governed by the frictional stress element.

ADSL을 위한 전화선로의 특성분석 및 등화기 설계

최성환,전진화,권호열 강원대학교 정보통신연구소 1999 정보통신논문지 Vol.3 No.-

In this paper, we evaluate transmission channel characteristics of telephone cable to be used in general. First, we measured the impedances of open and short circuits in order to obtain the RLCG parameters per unit length of transmission line. And we obtained the frequency-dependent transfer function and propagation constant for transmission line using these values. The channel impulse response is derived from the inverse Fourier of transfer function. We design channel equalizer for ADSL(Asymmetrical Digital Subscriber Line) using the measured impulse response of channel. The results shows that the transfer characteristics decrease sharply according to the length of transmission line. Finally, we verify efficacy of the proposed method by means of simulation.

여호와의 증인 환자에서 산과적 출혈 후 무수혈 치료 2예

김재령,여소진,이해혁,김정식,김태희,남계현,이권해,이임순,박진화,황경호 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

Jehovah's Witness comprise a unique obstetric population. Their refusal of blood stems from an interpretation of a literal translation of the Bible, and it is this belief that puts them at an increased risk of morbidity and mortality if hemorrhage occurs. We report two cases of a Jehovah's Witness who bled massively due to obstetric hemorrhage, refused blood transfusion and had profound anemia. The patients were treated with recombinant human erythropoietin, parenteral iron and oxygen. And they were treated on an intensive care unit with intermittent positive pressure ventilation. We reviewed with literature considering the therapy for acutely anemic patients who refuse transfusion to decrease the duration of the most severe anemia.

FET형 반도체센서 및 시스템 개발

손병기,조진호,최평,박이순,서화일,권대혁,고광락 경북대학교 센서기술연구소 1996 연차보고서 Vol.1996 No.-

기존의 센서들의 난점을 극복할 수 있는 새로운 형태의 FET형 전해질(electrolyte :H^+, K^+, Ca^2+, Na^+)센서소자 및 분석 시스템의 개발을 중점적으로 추진하였으며, FET형 포도당센서 및 압력센서의 개별 FET형 센서에 관한 연구도 병행하였다. FET형 전해질센서를 이용한 휴대용 전해질 측정기와 desktop형 4채널 전해질 분석기를 제작하였다. 또한 이 시스템을 소형화하기 위한 주문형 아날로그-디지탈 변환기 내장형 CMOS 프로세서를 설계하고 검증하였다. The main object of this research is to develope a new FET type electrolyte(H^+, K^+, Ca^2+, Na^+) sensors and analysis system which can overcome the problems of the conventional sensors. Parallel researches on FET type sensors such as glucose and pressure humidity are also in progress. A portable electrolyte meter and desktop 4-channel electrolyte analysis system is fabricated. A customized CMOS processor with built-in analog-to-digital converter is designed and verified.