나카가미-m 페이딩 채널 하에서 PLL 이득에 따른 DS/CDMA의 성능 분석

강찬석,박진수 대한전자공학회 2000 電子工學會論文誌 IE (Industry electronics) Vol.37 No.3

이동통신환경에서 수신신호의 진폭과 위상성분은 다중경로에 의한 페이딩(Fading) 영향을 받는다. 본 논문에서는 송수신 신호의 위상 차를 위상에러로 가정하고 Tikhonov 확률밀도함수를 이용하여 PLL(Phase Locked Loop)이득의 변화에 대한 DS/CDMA(Direct Sequence/code Division Multiple Access) DPSK(Differential Phase Shift Keying)시스템의 성능을 분석하였다. 그 결과, 위상에러를 고려하지 않은 DPSK시스템과 비교하여 수신기의 PLL이득을 조정함으로써 시스템의 성능을 향상시킬 수 있음을 알 수 있었다. 시스템의 비트 포율이 10-2에서 PLL이득이 1㏈에서 4.8㏈, 7㏈에서는 0.4㏈의 성능차를 보이며 30㏈에서는 두 시스템의 성능이 일치하게되어 PLL이 요구하는 이득의 상한이 30㏈임을 입증하였다. A received signal in mobile communication environments exhibits variation in both amplitude and phase due to the multipath fading. Therefore we analyzed the performance of DS/CDMA(Direct Sequence/code Division Multiple Access) DPSK(Differential Phase Shift Keying) system for the variations of PLL(Phase Locked Loop) gain with Tikhonov probability density function, assuming that the phase difference between transmitter and receiver signals is phase error. As a result, it is discovered that the performance of system could be improved by the control of PLL gain in compared with the DPSK system which does not consider the phase error. If the PLL gain is 1dB, the difference of two systems is 4.8dB and 0.4dB at 7dB. and if 30dB, it coincides. From above, it

성인학습인의 영성체험을 통한 영성리더십 개발 과정 탐색

강찬석,최은수 한국성인교육학회 2014 Andragogy Today : International Journal of Adult & Vol.17 No.2

This study aimed at building a theory on spiritual leadership development process through adult learners' spiritual experiences. For this purpose constructive grounded theory was used as methodology. This study revealed that the essence of spiritual experience was seeing true-Ⅰ and spiritual leadership was defined as leadership led by power emerging from spirituality. The theory and model through this study stated that spiritual leadership was the kind of leadership, in which the true-I helped all to be activated. The nature of the spiritual leadership development was not about developing new capacities that did not exist before. Rather, it was about inherent capacities that emerged and came to fruition, thus ‘emerging development’, which was in line with the development of "becoming". This study showed that from the perspective of generic spirituality, everybody could get spiritual experience and learning was the motivator transforming hardship to enjoyment. It could be expected that the subjectivity problem of postmodernism be solved and some of the obstacles of transformational learning be overcome from spiritual experience seeing true-Ⅰ. 본 연구는 성인학습인의 영성체험을 통한 영성리더십 개발과정을 밝혀 이론을 생성하는 것을 목적으로 했다. 연구문제를 해결하기 위하여 구성주의적 근거이론 방법론을 사용하였고, 성인학습인의 영성체험의 내용, 영성체험을 통한 삶의 전환과정, 영성리더십 개발의 결과적 특성 등 세 가지 하위 연구문제를 설정하였다. 연구 결과 영성체험은 참나를 만나는 체험이었고, 영성리더십은 영성에서 발현되는 힘으로 발휘되는 리더십으로 정의되었다. 결국 영성리더십은 참나가 주체로 되어 다살림의 작용으로 발휘되는 리더십 과정이었다. 영성리더십 개발의 성격은 새로운 능력을 ‘개발’한다기보다는 이미 갖추고 있는 능력이 발현하는 ‘발현적 개발’의 성격이었고, ‘됨’의 성장과정이었다. 본 연구를 통해 보편적 영성의 관점에서 영성체험은 누구나 가능하며, 학습은 고통을 즐거움으로 바꾸는 변화 추동자임을 확인하였다. 그리고 영성체험의 원리를 밝히고, 영적 성장과정인 ‘됨’의 성장과정에 대한 모형을 제시했으며, 리더십의 본질은 영성이라는 결론에 이를 수 있었다. 참나를 만나는 영성체험을 통해 포스트모더니즘의 주체문제를 해결하고, 전환학습의 장애도 극복할 수 있는 가능성을 확인하였다.

유가(儒家)적 관점에서 본 온정적 합리주의(CR) 리더십 패러다임의 특성에 대한 고찰

강찬석 한국성인교육학회 2016 Andragogy Today : International Journal of Adult & Vol.19 No.3

The purpose of this study was to explore characteristics and meanings relating to Choi’s compassionate rationalistic leadership paradigm. Special concerns were put in finding the degree of it’s transferability in Korean situations, and further the possibility of it’s getting the general validity beyond adult educational leadership boundary through analysing that paradigm from the perspective of confucianism, rendering cultural infra to Korean tradition. Leadership identity aiming at CR leadership paradigm still remained in the area of special concerns too. For this purpose, three research questions were set as follows: First, what is the characteristics of rationalism in CR leadership paradigm from the confucian perspectives? Second, what is the characteristics of compassionism in CR leadership paradigm from the confucian perspectives? Third, what is throughout the characteristics of CR leadership paradigm from the confucian perspectives? To solve these research questions, bibliographical searches were put to use. The study revealed that the rational reason in rationalism at the CR leadership was modern scientific reason, which was able to recover the position as the origin like logos with the help of ri emerging from confucian four clues(sadan) through compassionism, and overcome the instrumental nature of scientific reason. Also findings were that because the characteristics as origin were natural as well as spiritual, CR leadership paradigm was a kind of holistic approach considering reason, sensability and spirituality. The result of training CR components in CR leadership paradigm was sure to be the trustful leader having skills with great personalities. This meant the fusion between confucian paradigm centered in personality and western paradigm centered in performance. Finally, this study proposed that Swiss type political participation might be introduced to enlarge lifelong learning opportunities for leadership development. 본 연구는 성인교육 맥락에서 제시된 최은수의 온정적 합리주의 리더십 패러다임이 우리나라 전통문화의 기반을 이루고 있는 유가(儒家)적 관점에서 어떤 의미를 갖는지 분석함으로써 과연 한국적 상황에서도 이 패러다임이 통용될 수 있을 것인지, 성인교육 분야에 국한되지 않고 리더십 일반으로 적용될 수 있을 것인지, 온정적 합리주의 리더십 패러다임이 지향하는 전체적인 리더십의 모습은 어떠한지 등 특성과 시사점을 탐색하는 데 목적이 있었다. 연구문제는 첫째, 유가적 관점에서 본 CR리더십 패러다임에서의 합리주의 특성은 무엇인가? 둘째, 유가적 관점에서 본 CR리더십 패러다임에서의 온정주의 특성은 무엇인가? 셋째, 유가적 관점에서 본 CR리더십 패러다임의 전체적 특성은 무엇인가? CR리더십의 합리주의 패러다임에서의 합리적 이성은 다분히 근대적인 과학적 이성이었으나, 온정주의가 유가적 4단의 리(理)와 결합하여 과학적 도구로서의 이성을 극복하고 로고스적 근원성을 회복할 수 있었다. 근원성은 자연적이며, 영성이기 때문에 CR리더십 패러다임은 이성과 감성, 영성이 어우러지는 홀리스틱(holistic)한 리더십 접근이라 할 수 있다. CR리더십의 패러다임인 온정적 합리주의 요소들을 연마한 결과는 실력과 인성을 겸비한 신뢰(信)받는 리더로 드러났다. 이것은 인성을 중시하는 동양적 패러다임과 실적과 성과를 강조하는 서양적 패러다임을 종합한 특성을 지니고 있었다. 리더십 개발을 위한 평생학습기회의 창출을 위해 스위스식 정치참여의 확대를 제안하였다.

Jammer와 부호상관 효과를 고려한 FH / FSK 성능분석에 관한 연구 ( A Study on the Performance of FH / FSK Including Jammer and Code Correlation Effects )

강찬석,안중수,박진수 대한전자공학회 1991 대한전자공학회 학술대회 Vol.1991 No.7

학습자의 특성을 고려한 영어과 교수·학습 방법

강찬석 慶北大學校 師範大學 附屬國民學校 1998 現場硏究 Vol.19 No.-

DROS 자력계의 동작특성 및 심자도 측정

강찬석,이용호,권혁찬,김진목,유권규,박용기,이순걸,Kang, C.S.,Lee, Y.H.,Kwon, H.,Kim, J.M.,Yu, K.K.,Park, Y.K.,Lee, S.G. 한국초전도학회 2007 Progress in superconductivity Vol.8 No.2

We developed a SQUID magnetometer based on Double Relaxation Oscillation SQUID(DROS) for measuring magnetocardiography(MCG). Since DROS provides a 10 times larger flux-to-voltage transfer coefficient than the conventional DC-SQUID, simple flux-locked loop electronics could be used for SQUID operation. Especially, we adopted an external feedback to eliminate the magnetic coupling with adjacent channels. When the DROS magnetometer was operated inside a magnetically shielded room, average magnetic field noise was about 5 $fT/^{\surd}Hz$ at 100 Hz. Using the DROS magnetometer, we constructed a multichannel MCG system. The system consisted of 61 magnetometers are arranged in a hexagonal structure and measures a vertical magnetic-field component to the chest surface. The distance between adjacent channels is 26 mm and the magnetometers cover a circular area with a diameter of 208 mm. We recorded the MCG signals with this system and confirmed the magnetic field distribution and the myocardinal current distribution.

조셉슨 접합 어레이의 전류 차단특성

강찬석,김기웅,유권규,이성주,권혁찬,황성민,이용호,김진목,이상길,Kang, C.S.,Kim, K.,Yu, K.K.,Lee, S.J.,Kwon, H.,Hwang, S.M.,Lee, Y.H.,Kim, J.M.,Lee, S.K. 한국초전도학회 2009 Progress in superconductivity Vol.10 No.2

A current limiter was manufactured using a Josephson junction array to cut off an excessive current flowing into the SQUID sensor. The Fabricateed Josephson junction array was connected in series with a flux transformer that consists of a pick-up coil and an input coil, and the flux transformer was inductively coupled with a Double Relaxation Oscillation SQUID(DROS). The flux-voltage modulation curve was induced by applying an AC magnetic field whose magnitude was far smaller than that of the DC magnetic field. A change in the flux-voltage modulation curve of the SQUID was observed while the DC magnetic field was increased, to qualitatively examine the current limiting characteristic of the Josephson junction array. As a result, it was found that the SQUID flux-voltage modulation curve disappeared at the critical current of the Josephson junction array, which indicates that the Josephson junction array properly works as a current limiter.

다양한 기저선을 갖는 1차 및 2차 미분계의 신호크기 및 신호 대 잡음비 조사

강찬석,유권규,이용호,권혁찬,김진목,박용기,이순걸,Kang, C.S.,Yu, K.K.,Lee, Y.H.,Kwon, H.,Kim, J.M.,Park, Y.K.,Lee, S.G. 한국초전도학회 2007 Progress in superconductivity Vol.9 No.1

We investigated signal-to-noise ratios (SNRs) of magnetocardiography (MCG) signals using the first-order and the second-order gradiometers of different baselines. The MCG signals were recorded using a measurement system with 61 magnetometers which measured the normal magnetic component to the chest surface. The distance between the chest surface and the bottom of the dewar was changed from 0 cm to 15 cm, and the MCGs were measured for each distance. By subtracting the other signals (distance = 1 to 15 cm) from the reference signal (distance =0 cm), we could simulate the first-order and the second-order gradiometer signals with various baselines. In addition, to evaluate the reproducibility of the simulation, we fabricated the wire wound first-order and second-order gradiometers which measured a normal magnetic component to the chest surface. The baselines of the first-order gradiometers were, respectively, 50 mm, 70 mm and 100 mm and the baseline of the second-order gradiometer was 50 mm. Using these gradiometers, we recorded the MCG signal and compared the SNR between the simulation and the measurement.

Simple simulation method for investigating the performance of a SQUID gradiometer corresponding to a baseline length

강찬석,유권규,김기웅,권혁찬,김진목,이용호 한국물리학회 2012 Current Applied Physics Vol.12 No.5

Since the Superconducting Quantum Interference Device (SQUID) is the most sensitive magnetic field detector, it is widely used for measuring very weak biomagnetic signals, such as a Magnetocardiography (MCG). However, because the SQUID is easily affected by environmental magnetic noises, it is often used as a form of gradiometer suppressing spatially homogeneous field noises. The characteristic of the SQUID gradiometer mainly depends on the distance between the connected coils, that is, a baseline. Accordingly,in order to fabricate a gradiometer, the investigation of a proper baseline for the MCG signal is necessary. For the investigation, however, various gradiometers having different baselines have to be fabricated and tested, which required too much cost and effort. In this study, we suggest a simple simulation method to investigate the performance of a SQUID gradiometer depending on the baseline. In addition, in order to verify the reliability of our simulation, we fabricated wire wound axial first-order gradiometers (50 mm, 70 mm, and 100 mm baseline) and a second-order gradiometer (50 mm baseline)and compared the characteristics of the measured gradiometer signal with the simulated signal.

성인교육자의 변혁적 리더십 역량 개발을 위한 전환학습과 동양의 깨달음과의 융합적 접근

강찬석,최은수 숭실대학교 한국평생교육ㆍHRD연구소 2012 평생교육 · HRD연구 Vol.8 No.2