• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.37-42
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• 2003

We have analyzed the characteristics of the sea surface winds and wind waves near the Korean marginal seas on the basis of prediction results of the sea surface winds from MM5/KMA model, which is being used for the operation system at the Korea Meteorological observation buoy data to verify the model results during Typhoon events. The correlation coefficients between the models and observation data reach up to about 95％, supporting that these models satisfactorily simulate the sea surface winds and wave heights even at the coastal regions. Based on these verification results, we have carried out numerical experiments about the wave modulation. When there exist an opposite strong current for the propagation direction of the waves or wind direction, wave height and length gets higher and shorter, and vice versa. It is proved that these modulations of wave parameters are well generated when wind speed is relatively week.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1572-1577
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• 2003

The powershift transmission have the advantage of easier operation and higher efficiency by using the hydraulic clutch and mechanical power transfer system. It is important to control the engaging pressure and time. The hydraulic control system is used for these controls of the modulator valve, the accumulator, the sump valve and etc. This study have made a simulator for verifying the pressure characteristic of the shuttle powershift transmission and developed the computer simulation model of the hydraulic components and system by using 'AMESim'. As a result, the design parameters which have an effect on the pressure modulation are verified to the spring stiffness of the modulator valve and the volume of the accumulator.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1211-1213
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• 2004

CCFL(cold cathode fluorescent lamp) are used to backlight of LCD(liquid crystal display). CCFL dimming methods are used to pulse frequency modulation(PFM) or pulse width modulation(PWM). In this paper, design of CCFL driving and control circuit by half-bridge type series and parallel resonant inverter that variable frequency modulation method to control the output voltage current. Inverter switching frequency is higher than resonant frequency for stable operating, and it is possible dimming control. On the basis of equivalent circuit, the validity of this study is confirmed by the comparison of simulation and experimental result.

• 한국자기공명학회논문지
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• 제6권1호
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• pp.20-37
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• 2002

MnAPSO-34 and Mn-impregnated SAPO-34(Mn-SAPO-34) sample were prepared with various manganese contents and studied by electron spin resonance(ESR) and electron spin echo modulation(ESEM). Electron spin echo modulation analysis of 0.07mo1 ％ Mn(relative to p) in MnAPSO-34 with adsorbed D$_{2}$O shows two deuteriums at 0.26 nm and two at 0.36 nm from Mn. This suggests that two waters hydrate an MnO$_{4}$ configuration with a D-O bond orientation for the waters as expect for a negatively charged site at low manganese content (0.1 mol％), the ESR spectra of MnAPSO-34 and MnH-SAPO-34 exhibit the same parameters(g 2.01 and A 89 G), but the spectra obtained from MnAPSO-34 samples are better resolved. The decomposition temperature of as-synthesized MnAPSO-34 were in the range of 200-600 $^{\circ}C$ of the morpholine which is 12 $^{\circ}C$ higher than that in as-synthesized MnH-SAPO-34. Infrared spectra showed that the position of a band at 3450 $cm^{-1}$ / shifted about 15 $cm^{-1}$ / toward higher energy in MnAPSO-34 versus MnH-SAPO-34. The modulation depth of the two-pulse ESE of MnAPSO-34 with adsorbed D$_{2}$O is deeper than that of MnH-SAPO-34 with adsorbed D$_{2}$O. Three-pulse ESEM of MnAPSO-34 and MnH-SAPO-34 with adsorbed deuterium oxide shows that the local environments of manganese in the hydrated samples are different, suggesting that Mn(II) is framework substituted in MnAPSO-34 since it obviously occupies an extraframework position in MnH-SAPO-34.

• 한국통신학회논문지
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• 제39C권11호
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• pp.1042-1049
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• 2014

군의 MicroWave 통신 환경에서 회선 설계를 위해 링크거리, 가용도, 전송용량은 중요한 요소이다. 현재 고정용 변조방식으로 운용, 미래 전송용량 증대가 가능한 변조방식으로 진화될 예정이다. 링크 거리에 따라 페이딩 발생확률의 증가로 장거리의 경우 고신뢰의 전송품질을 지속적으로 보장하기 어려울 수 있다. 대용량 전송을 위한 변조방식의 경우 장거리가 될수록 링크버짓에서 페이드 마진의 저하로 가용도가 감소되어 QoS 보장에 있어 제한사항이 발생할 수 있다. 본 논문에서는 군 MicroWave 무선 링크에서의 링크거리를 고려한 대역폭 가변 할당 및 우선순위 전송 용량 비율 설정을 이용한 우선순위 전송 기법을 통해 무선 전송 성능 향상기법을 제안하고 링크 설계를 위한 채널 전송 용량 산출방안을 제시한다.

• 한국자기공명학회:학술대회논문집
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• 한국자기공명학회 2002년도 International Symposium on Magnetic Resonance
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• pp.80-80
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• 2002

MnPSO-34 and Mn-impregnated SAPO-34 (Mn-SAPO-34) sample were prepared with various manganese contents and studied by electron spin resonance (ESR) and electron spin-echo modulation (ESEM). Electron spin-echo modulation analysis of 0.07mol ％ Mn(relative to p) in MnAPSO-34 with adsorbed D$_2$O shows two deuteriums at 0.25 nm and two at 0.36 nm from Mn. This suggests that two waters hydrate an MnO4 configuration with a D-O bond orientation for the waters as expect for a negatively charged site at low manganese content (0.07 mol％), the ESR spectra of MnAPSO-34 and MnH-SAPO-34 exhibit the same parameters (g 2.02 and A 87 G), but the spectra obtained from MnAPSO-34 samples are better resolved. TGA of as-synthesized MnAPSO-34 shows that the decomposition temperature in the range 200-$600^{\circ}C$ of the morpholine is 12$^{\circ}C$ higher than that in as-synthesized MnH-SAPO-34. Infrared spectra shows that the position of a band at about 15 cm-1 toward higher energy in MnAPSO-34 versus MnH-SAPO-34. The modulation depth of the two-pulse ESE of MnAPSO-34 with absorbed D$_2$O is deeper than that of MnH-SAPO-34 with absorbed D$_2$O. Three-pulse ESEM of MnAPSO-34 and MnH-SAPO-34 with absorbed deuterium oxide shows that the local environments of manganese in the hydrated samples are different, suggesting that Mn(II) is framework substituted in MnAPSO-34 since it obviously occupies an extra-framework position in MnH-SAPO-34

• 한국통신학회논문지
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• 제31권11C호
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• pp.1037-1043
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• 2006

본 논문에서는 차세대 대용량 데이터 저장장치로 부각되고 있는 홀로그래픽 데이터 저장장치를 위한 2차원 변조코드를 제안한다. 단위 면적당 기록 밀도의 증가로 인한 인접 심볼간 간섭과 3차원적인 홀그래픽 저장으로 인한 페이지간 섭 등에 강인한 성능을 갖도록 같은 페이지 내의 1과 0의 개수가 거의 동일하도록 설계하였으며, 또 가능한 많은 1과 0의 천이가 일어나도록 설계하였다. 제안된 코드의 코드율은 5/9로서 기존의 4/9 코드보다 25%의 코드율 개선을 하였다.

• 한국산학기술학회논문지
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• 제17권7호
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• pp.518-528
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• 2016

재즈 스탠다드 곡들에 있어서 많은 곡들이 1개의 조성 안에 있는 것처럼 보이지만 적어도 한 개 이상의 새로운 조가 비록 짧은 순간이라 할지라도 성립되는 경우가 많다. 게다가 어떤 곡들은 여러 차례에 걸쳐 일시적인 조성의 변화를 내포하기도 하는 데, 이 경우 코드 진행을 '동형진행'하여 조성을 일시적으로 변화시키는 경우가 많으며 이를 '동형진행을 통한 일시적 전조'라고 지칭한다. 동형진행하게 되는 코드진행으로는 장조 및 단조의 II-V-I 진행이 많이 쓰이며, 동형진행적 일시적 전조기법에 있어서 가장 많이 쓰이는 패턴은 장2도 혹은 단2도 간격으로 하행하는 패턴이다. 장2도 간격으로 하행하는 전조 패턴은 가장 많이 사용되는 기법으로, 일례로 두 번을 사용하게 되면 인접하는 상황에서 3개의 조성이 나타나게 된다. 우리는 이 기법을 통하여 감정이 고조되었다가 급격히 가라앉는 현상을 효과적으로 표현할 수 있다. 반음 아래로의 전조는 더욱 극적이라고 표현할 수 있다. 반 음 아래로의 전조 기법은 인접하는 두 개의 조성 간의 대비적인 측면을 더욱 높일 수 있어서 한층 더 드라마틱한 효과를 낼 수 있다.

• 대한감각통합치료학회지
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• 제1권1호
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• pp.25-37
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• 2003

Objective : To explore the effectiveness of sensory integration program of home-based outcomes in child with sensory modulation disorder. Methods : This study used the simple case study. The subjects were three children diagnosed as developmentally delayed who 14 month and 26 month males and a 15 month female. After initial evaluation, parents were educated on sensory diet and Wilbarger protocol method for 30 minutes twice for home-based treatment and asked to make out daily treatment planning. To measure improvement of children, we used for the Denver Developmental Screening Test II(DDST II), Wee Functional Independence Measure(WeeFIM), hand function, functional ability, oral motor function, Sensory Profile(Dunn, 1999). Results : After the home-based program, the scored of the Denver Developmental Screening Test II(DDST II), Wee Functional Independence Measure(WeeFIM), hand function, functional ability, oral motor function, Sensory Profile(Dunn, 1999) were higher rather than initial evaluation after the home-based program. Conclusion : The home-based program is effective for children with sensory modulation disorder but parents had to be educated by therapist specific evaluation and treatment in sensory integration.

• Journal of Power Electronics
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• 제14권1호
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• pp.48-60
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• 2014

Multilevel inverters have been widely used for high-voltage and high-power applications. Their performance is greatly superior to that of conventional two-level inverters due to their reduced total harmonic distortion (THD), lower switch ratings, lower electromagnetic interference, and higher dc link voltages. However, they have some disadvantages such as an increased number of components, a complex pulse width modulation control method, and a voltage-balancing problem. In this paper, a novel nine-level reduced switch cascaded multilevel inverter based on a multilevel DC link (MLDCL) inverter topology with reduced switching components is proposed to improve the multilevel inverter performance by compensating the above mentioned disadvantages. This topology requires fewer components when compared to diode clamped, flying capacitor and cascaded inverters and it requires fewer carrier signals and gate drives. Therefore, the overall cost and circuit complexity are greatly reduced. This paper presents modulation methods by a novel reference and multicarrier based PWM schemes for reduced switch cascaded multilevel inverters (RSCMLI). It also compares the performance of the proposed scheme with that of conventional cascaded multilevel inverters (CCMLI). Simulation results from MATLAB/SIMULINK are presented to verify the performance of the nine-level RSCMLI. Finally, a prototype of the nine-level RSCMLI topology is built and tested to show the performance of the inverter through experimental results.