奚琴의 音響學的 特性

임무열,윤화중,Lim, Moo-Yeol,Yoon, Wha-Joong 한국음향학회 1990 韓國音響學會誌 Vol.9 No.3

奚琴 音質의 音響學的 特性을 조사하기 위해 奚琴音의 파워스펙트럼과 時間波形을 FFT Analyzer를 이용하여 분석하였다. 奚琴絃의 張力과 遠山(bridge)의 위치, 腹板(top plate)의 두께등을 변화시키면서 분석을 하였다. 실험에 의하여 다음과 같은 결론을 얻었다. 腹板의 共振周波數가 絃의 基音의 周波數보다 높기 때문에, 基音의 音壓보다 腹板의 共振周波數 부근의 上音들의 音壓이 더 큼을 알았다. 絃의 張力이 강할 때와 遠山이 腹板의 중앙에 위치하였을 때가 音質이 보다 우수하였다. 奚琴 遊絃의 inharmonicity 계수는 0.049 cents/$n^2$이었다. 5kHz 이상의 上音은 발견할 수 없었으며, 奚琴의 inharmonicity가 violin의 inharmonicity보다 큰 값을 나타내었는데 이를 통해 奚琴음의 明瞭度와 豊富性이 부족하다는 것을 알 수 있었다. 奚琴筒의 共振周波數(MAR)와 腹板의 共振周波數(MWR)의 周波數比는 1 octave 정도일 때 奚琴이 가장 좋은 음색을 갖는다는 것을 밝혔으며 이때 腹板의 두께는 4.5mm 정도이다. In order to investigate the acoustical characteristics of the Hae-keum (Korean traditional musical instrument) tone quality, the spectrum and wave form of Hae-keum sounds were analyzed by the FFT Analyzer. The analysis was carried out by the varying of the tension of Hae-keum strings, the positions of bridge and the top plate's thickness of Hae-keum respectively. According to the experiment, the following results are obtained ; the over tone's amplitude nearby the top plate resonance frequency is greater than the fundamental tone's amplitude because the top plate resonance frequency is higher than the fundamental tone's frequency. Tone qualities are better when the bridge is situated in the middle of top plate and the tension of strings is larger. The inharmonicity coefficient of the Hae-keum's second string is 0.049 cents/$n^2$. The brilliance and richness is poor, because we seldom found the over tone over 5kHz and the inharmonicity of the Hae-keum is greater than that of a violin. Also we confirmed that we are able to get the best tone quality in 4.5mm thickness of the Hae-keum's top plate.

Sol - Gel 법에 의한 PbZrO3 - PbTiO3 - Pb ( Ni1/3Nb2/3 ) O3 박막의 전기적 특성

임무열,구경완,한상옥 ( Moo Yeol Lim,Kyung Wan Koo,Sang Ok Han ) 한국전기전자재료학회 1997 전기전자재료학회논문지 Vol.10 No.2

Sol - Gel 법에 의한 PbZrO3 - PbTiO3 - Pb(Ni1/3Nb2/3)O3 박막의 물리적 특성

임무열,구경완,김성일,유영각 ( Moo Yeol Lim,Kyung Wan Koo,Sung Il Kim,Young Kag Yoo ) 한국전기전자재료학회 1996 전기전자재료학회논문지 Vol.9 No.10

군 복무 중 취득한 자격증의 취업효과에 대한 연구

박창호(Chang-Ho Park),송재근(Jae-Geun Song),이임주(Im-Joo Lee),임무열(Moo-Yeol Lim),윤상은(Sang-Eun Yoon),배종환(Jong-Hwan Bae),김승현(Seung-Hyun Kim) 충남대학교 경영경제연구소 2016 경영경제연구 Vol.38 No.2

자격증이 취업에 미치는 영향에 대해서는 많은 연구가 있었지만 군 복무 중 취득한 자격증이 취업에 도움이 되는지에 대해서는 알려진 것이 거의 없다. 만약, 군 복무 중 취득한 자격증이 사회에서 필요로 하는 자격증이 된다면 군 복무기간도 인적자본을 축적하는 좋은 기회로 작용할 것이다. 본 연구는 한국직업능력개발원의 한국교육고용패널(Korean Education & Employment Panel: KEEP) 자료를 이용하여 군 복무 중 취득한 자격증이 제대 후 취업에 도움이 되는지를 탐색하였다. 연구 결과, 군 복무 중 취득한 자격증은 전반적으로 첫 일자리 취업 소요기간에 영향을 미치지 못했으나 일부 자격증은 취업소요기간 단축효과가 있었고, 임금도 다소 상승하는 것으로 나타났다. 하지만 일자리 형태 결정에 미치는 영향은 거의 없는 것으로 확인되었다. Although there exist many studies about the effects of licenses on employment, little is known about the effects of licenses acquired during military service on employment. If the licenses acquired during military service is helpful in the labor market, it will help unemployed youth find a job after graduation from university. Using the Korea Education & Employment Panel (KEEP) data published by the Institute for Vocational Education and Training, we examine whether licenses acquired during military service can have a significant effect on employment, the type of jobs, and wages. Our results indicate that young people with licenses acquired during military service have a shorter period to find a first job and have greater wages in the first job. However, the licenses obtained in military services do not have a significant effect on the type of a first job.

졸-겔법에 의한 PZT-PNN 薄膜의 特性

임무열,구경완 永同工科大學校 1995 硏究論叢 Vol.1 No.1

유기금속을 사용한 졸-겔 스핀 코팅법으로 PZT-PNN 박막을 제조하였으며, diethanolamine을 안정화물질로 사용하였다. PT:PZ:PNN의 코팅 용액의 mol%는 각각 #1(50:40:10), #2(50:30:20), #3(45:35:20), #4(40:40:fO), f5(40:50:10), #6(35:45:20) 그리고 #7(30:50:20)으로 제조하였다. 스핀 코팅된 박막의 잔류 유기물을 제거하기 위해 350t에서 예비소결을 하였고, 박막의 결정화를 위해 450℃~ 700℃에서 소결하였다. 백금 기판과 Pt/TiN/Ti/TiN/Si 기판 위에 박막을 성장하였으며, 500℃의 소결에서도 perovskite 상이 출현하였다. 결정성이 가장 양호한 소결온도는 700℃이었다. Sawyer-Tawer 회로를 이용하여 박막위 P-E 이력곡선을 관찰하였다. 박막의 항전계와 잔류분극은 각각 28.8 ㎸/㎝과 18.3 uC/㎠이었다. 유전상수 k는 128 ~ 1120의 값을 나타내었고, 상경계(40:40:20 ㄹmol%)에서 최대값을 보여주었다. 박막의 진성파괴전압은 27.0 ~ 60.0 ㎹/m이었으며, 소결온도가 올라갈수록 파괴 전압은 낮아지는 경향을 나타내었다. PbTiO_3-PbZrO_3-Pb(Ni_1/3Nb_2/3O_3)(PZT-PNN) thin films were been prepared from corresponding metal organics partially stabilized with diethanolamine by the sot-gel spin coating method. The each mol rates of PT:PZ:PNN solutions were #1(50:40:10), #2(50:30:20), #3(45:35:20), #4(40:40:20), #5(40:50:10), #6(35:45:20) and #7(30:50:20) respectively. The spin-coated PZT-PNN films were heat-treated at 350t for decomposition of residual organics, and were heat-treated at temperature between 450t and 750t for crystallization. The substrates, such as Pt and Pt/TiN/Ti/TiN/Si were used for the spin coating of PZT-PNN films. The perovskite phase was observed in the PZT-PNN films which were heat-treated at 500℃ The crystallization of the PZT-PNN films was optimized at 700℃ of sintering temperature. The P-E hysteresis curve was drawn by Sawyer-Tower circuit with PZT-PNN film. The coercive field and the remanent polarization of PBT-PNN film was 28.8 ㎸/㎝ and 18.3 uC/㎠ respectively. Its dielectric constants were shown between 128 and 1120, and become maximum value in MPB. The break down voltages of PZT-PNN films were shown between 27.0 and 60.0 ㎹/m.

대전 3ㆍ4 공업단지 일대의 소음 특성

임무열,강호 忠南大學校 環境問題硏究所 1996 環境硏究 Vol.14 No.-

The living noise was investigated around the Taejon 3th and 4th industrial complex in August and November 1996. The noise level in A-1 place was over the living noise exhaust standard. The noise levels in A-2 and A-3 place were less than the living noise exhaust standard. The noise spectrum of the incinerator in A-1 place indicate harmonic structure of which fundamental frequency was 80-100 Hz. The noise spectrum in A-2 place indicate white noise spectrum.

BRS 생체정보 분석방법(分析方法)의 정확도(正確度) 확인 연구

유상구,임무열,오상문,유경배,신연호,박병운,이완희 한국정신과학학회 1998 韓國精神科學學會誌 Vol.2 No.2

BRS는 인간의 잠재능력을 적극적으로 계발 · 활용하여 임의의 시료에 대한 미지 (未知)의 생체정보 (Bio-Information)를 편리하게 분석할 수 있는 효과적이고 경제적인 분석장비이다. 그러나 BRS와 관련된 분석방법 자체의 정확도에 대한 연구는 충분하게 이루어지지 않고 있다. 그래서 BRS 분석방법의 정확도를 과학적으로 확인해보기 위해서 본 연구를 진행했다 실험결과, BRS에 의한 생체정보 분석방법 의 정확도는 측정자의 숙련정도에 따라 다르지만 고급 측정자의 경우에는 95% 이상의 높은 확률로 표준시료의 생체정보를 정확하게 분석할 수 있으며, 측정자의 분석능력이 떨어지는 경우에는 여러 명의 측 정자를 대상으로 비교검토(Cross-Check) 방식으로 실험을 보완하면 90% 이상의 정확도를 확보할 수 있었다. BRS is a sort of analysis-instrument which help to estimate some Bio-Information for a sample conveniently and effectively But, for lack of the study to verify the confidence-degree of the Bio-Information analysis method related to BRS, the availability of the method is not known clearly yet, It was the reason that made authors perform this study And It was possible to arrive at the following two conclusions I though the confidence-degree of the Bio-Information analysis method ny BRS was different according to the degree of the expertness of a person using the instrument in the case of the very skillful expert, the confidence-degree for the standard sample used in this study was reached to 95% up 2 In the general case, to improve of the confidence-degree of the Bio-Information analysis method by BRS, the cross-check method by the several measuring person can be introduced.

DEA 첨가 금속 Alkoxide를 사용한 PZT 박막의 제조 및 특성 평가

윤화중,임무열,구경완,최명진 충남대학교 기초과학연구소 1994 忠南科學硏究誌 Vol.21 No.1

Lead acetate trihydrate, zirconium iso-propoxide and titanium iso-propoxide used for the starting material to fabricate PZT coating solution. Iso-metoxy-ethanol used for the solvent of the starting material. Adding diethanolamine formed the chelate compound and prevented the hydrosis of coating solution. The coating sol solution is changed to M-O-M structure polymer gel by adding H_2O, and the polymer gel has the more strong bonding force. The cross-sectional SEM micrograph of PZT thin film showed that the metal of lower electrode was silicated with SiO_2 of buffer layer. The SIMS depth profile for PZT thin film indicated that the metal of lower electrode and silicon was diffused up to the upper part of PZT thin film. For the X-RD data of PZT thin film, the thin film on Pt substrate and with Ti buffer layer had strong perovskite phase. The PZT thin films measured by Sawyer-Tower circuit showed feroelectric characteristic representating D-E hysterisis curve. The remanent polarization and coercive field of the film was 1.92 C/㎠ and 33.3kV/㎝. I-V characteristic curve showed that the leakage currents and break down voltages of PZT thin films on Ni/SiO_2/Si, Ti/SiO_2/Si, Pt/SiO_2/Si substrate was 1.43 × 10 exp (-10) A/㎠, 1.19×10 exp (-10) A/㎠, 2.28×10 exp (-10) A/㎠ and 0.334 MV/㎝, 0.33 MV/㎝, 0.11 MV/㎝ each. C-V curve indicated dielectric constant 57 The resistance antiresonance frequency of PZT film was 612 ㎒, and the resistance was 14 ㏀ at that frequency.

졸겔법으로 제작한 PZT-PNN 박막의 전기적 특성

윤화중,임무열,구경완 충남대학교 기초과학연구소 1995 忠南科學硏究誌 Vol.22 No.2

PbTiO_3-PbZrO_3-PbNi_1/3Nb_2/3O_3(PZT-PNN) thin films have been prepared from corresponding metal organics partially stabilized with diethanolamine through the sol-gel spin coating process. The each mol rates of PT:PZ:PNN sol solutions were #1(50:40:10), #2(50:30:20), #3(45:35:20) and #4(40:40:20). The spin-coated PZT-PNN films were heat-treated at 350℃ for decomposition of residual organics, and were heat-treated at temperature between 450℃ and 750℃ for crystallization. The substrates, such as Pt and Pt/TiN/Ti/TiN/Si were used for the spin coating of PZT-PNN films. The perovskite phase was observed in the PZT-PNN films which were heat-treated at 500℃. The crystallization of the PZT-PNN films was optimized at 700℃ of sintering temperature. The P-E hysteresis curve was drawn by Sawyer-Tower circuit with PZT-PNN film. The coercive field and the remanent polarization of PZT-PNN film was 28.8 kV/㎝ and 18.3 μC/㎠ respectively. Its dielectric constants K were shown between 128 and 1120, and become maximum value in MBP. The Curie pont of PZT-PNN film indicated 330℃ according to the measurement of dielectric constant. The break down voltages of PZT-PNN films were shown between 27.0 and 60.0 MV/m.

진동 센서용 압전 박막의 제조 및 그 특성 분석

윤화중,서일환,구경환,임무열,이진호 경북대학교 센서기술연구소 1993 연차보고서 Vol.1993 No.-

졸-겔 spin-coating법을 이용하여 PZT 압전 박막을 제작하고 그 물리적 및 전기적 성질을 평가하여 진동 측정용 센서로서의 적용 가능성을 검토하였다. PZT의 원료로는 Pb-acetate, Zr-propoxide 그리고 Ti-propoxide를 사용하였다 SEM 단면사진의 결과 하부전극 금속이 silicate화 하였고, SIMS 분석결과 Si와 하부전극의 금속이 PZT 박막의 상층부까지 확산된 것을 알 수 있었다. X-RD로 박막의 결정성을 조사한 결과 하부전극을 Pt로 한 박막과 buffer 층으로 Ti를 증착한 박막에서 강한 perovskite 상이 나타났다. D-E Hysterisis 곡선을 관찰한 결과 강유전성을 나타내며, 항전계는 33.3 ㎸/㎝, 잔유분극은 1.92 C/℃ 이었다. 박막의 비유전율은 57이었다. 박막의 resistance와 impedance의 반공진 주파수는 612 ㎒이고, 이때의 resistance 값은 14 ㏀이었다. 박막의 진동에 대한 주파수 응답 곡선을 측정 결과 12000 ㎐ 이하 저주파 영역에서는 응답 특성이 떨어지고 12000 ㎐ 이상의 어느 정도 높은 주파수 영역에서 응답 특성이 양호하다는 것을 알 수 있었고, 20000 ㎐ 100 ㏈(V)의 진동에 대해 151.4 ㎶의 응답을 나타내었다. PZT thin film was prepared by Sol-Gel spin-coating method and it's physical and electrical caracteristics were appreciated. Pb acetate, Zr propoxide and Ti propoxide used for the starting material to fabricate PZT coating solution. The cross-sectional SEM micrograph showed that the metals of lower electrode was silicated. The SIMS depth profile indicated that the metal of lower electrode and silicon diffused up to the upper part of PZT thin film. For the X-RD data of PZT thin film, the thin film on Pt substrate and with Ti buffer layer had strong perovskite phase. The PZT thin films measured by Sawyer-Tower circuit showed feroelectric characteristic representating D-E hysterisis curve. The remanent polarization and coercive field of the film was 1.92 C/㎠ and 33.3kV/㎝. Dielectric constant of Film is 57. The resistance and impedance antiresonance frequency was 612 ㎒, and the resistance was 14 ㏀ at that frequency. The frequency response curve of PZT film showed that the PZT film responded sensitively at the high frequency, and response voltage of PZT film was 151.4 ㎶ at 20,000 ㎐ 100 ㏈(V) frequency.