近隣住區單位로서의 아파트團地內 共同施設의 計劃에 關한 硏究

이우종 서울大學校 大學院 1981 국내석사

Three essays on corporate valuation

이우종 서울대학교 대학원 2008 국내박사

Event-related Potential analysis using elastic net logistic regression

이우종 서울대학교 대학원 2016 국내석사

The objective of the thesis is to explore whether regularization techniques can be applied to ERP analysis, and which type of regularization is adequate. This thesis proposes elastic net regularization logistic regression as a good candidate of data analytic method for Event-Related Potential analysis (ERP). Specifically, regularization techniques are used to identify latency in ERP. Study 1 tested whether regularization logistic regression can classify latency using simulated ERP data. It showed that ridge and lasso could identify latency information. In study 2, the same analyses were applied to actual ERP data. Ridge regression can identify latency information wheras lasso cannot.

배터리 에너지 저장장치 기반의 독립형 마이크로그리드 해석 및 설계

이우종 忠南大學校 大學院 2015 국내박사

This dissertation proposes control algorithm and operation methods of stand-alone microgrid which can be applicable to islands based on battery energy storage system. The stand-alone microgrid is composed of battery energy storage system(BESS), diesel generator(DG) and renewable source. Renewable source is a clean energy such as photovoltaic(PV) or wind power, PV was applied as renewable source in this dissertation. BESS operates by main source in the stand-alone microgrid and supplies power to loads, DG and PV operate by auxiliary power supply of BESS. DG does not operate in the usual. First, an analysis and modeling of diesel generator for stand-alone microgrid. The output of diesel generator can be calculated by the phase difference between voltage and current as well as the diesel generator parameter such as mutual impedance, field current and rotor angle. Considering the different d-q frame impedance in silent synchronous generator, the output of diesel generator is analyzed for equation and verified by simulation. The diesel generator modeled by considering the time delay for actuator, diesel engine and exciter. The controller of diesel generator is divided into governor and exciter. The governor consists of speed controller and active power controller, where speed controller maintains frequency as 60Hz and active power tracks active power reference. On the other hand, the exciter consists of voltage controller and reactive power controller, where voltage controller controls 380VLL and reactive power is controlled as zero. When the active power reference is changed as 0.1pu in the grid connected mode, the active power takes 10 seconds to reach the steady state and the reactive power is maintains as zero. Also, when the load is changed from 3kW to 27kW in stand-alone mode, the frequency and voltage are dropped as 1.8Hz and 2.4V instantly. The dropped frequency and voltage take 30 seconds and 60 seconds to recover into the steady state. The 50kW diesel generator is tested and experiment results are well matched with the simulation results. Thus, it can be expected operation of the diesel generator in a stand-alone microgrid by MATLAB/Simulink simulation. Second, a analysis and propose control algorithm of battery energy storage system for stand-alone microgrid. The operation of 3-phase DC-AC inverter is divided stand-alone mode and grid-connected mode. The 3-phase DC-AC inverter controls CVCF(Constant Voltage Constant Frequency) and selective harmonic eliminate methed in stand-alone mode, and BESS supplies stable sinusoidal voltage to balanced, unbalanced and non-linear loads. The total harmonic distortion(THD) of line-to-line load voltage is 1.2% in the balanced load. THD of is reduced from 5.2% to 1.4% and 6.7% to 3.5%, respectively unbalanced and non-linear load. BESS can be supplies sinusoidal balanced voltage to unbalanced load because the voltage unbalanced factor(VUF) of is reduced from 5.2% to 1.4% in the unbalanced load. The 3-phase DC-AC inverter operates charge mode by CC-CV(Constant Current Constant Voltage) control and compensation harmonic current in grid-connected mode, and THD of load current is 4.5%. Lastly, the stand-alone microgrid is composed of BESS, DG and PV in this dissertation. The stand-alone microgrid operation is divided into four modes; normal mode, overvoltage protection mode, charge mode and manual mode. Feasibility of control and stable operation method for a stand-alone microgrid will be verified through simulation by MATLAB/Simulink.

中國繪畵思想 및 文學性에 對한 硏究 : 揚州八怪의 作品世界를 中心으로

이우종 建國大學校 敎育大學院 1988 국내석사

尨大한 自然環境을 背景으로 形成된 中國大陸은 人類文明의 四大發祥地의 하나라는 事實이 말해주고 있듯이 悠久한 歷史와 文化的인 傳統을 갖고 있다. 이와같은 歷史와 文化的 背景 속에서 成立, 發展되어 온 中國藝術, 特히 繪畵는 美術史的인 側面에서도 獨自的인 領域을 차지하고 있거니와, 表現의 接近方法에 있어서 對象에의 充實한 描寫보다는 作家自身의 精神을 繪畵化한다는 점에서 더욱 뚜렷한 樣式的 特徵을 보이고 있다. 이러한 中國繪畵의 特徵은 尨大한 自然環境과 漢字라는 固有의 象形文字를 바탕으로 形成된 文化的 特性을 反映한다. 그러나 繪畵의 發展에 있어 보다 直接的인 影響을 미친 것은 中國 固有의 思想이었다. 敬天思想에서 비롯된 自然崇拜思想 및 人間尊重思想, 그리고 自然에 同化하는 것이 人生의 참 價値라는 自然思想으로 發展 變貌되어 왔다. 다시 말하면 모든 藝術은 思想의 影響圈內에 있었다. 그 過程에서 中國繪畵는 詩畵一致思想을 胎動, 從來의 寫實主義 槪念을 떨쳐버리고, 마침내 文字香이 넘치는 中國 特有의 繪畵樣式으로 定着된다. 여기에는 詩精神, 卽 文學精神이 깊이 介在되고 있는 것이다. 따라서 本稿는 中國思想의 變遷과 特徵을 要約하는 한편, 中國의 代表的인 三大思想, 卽 道家思想, 儒家思想, 禪家思想이 中國繪畵에 어떠한 影響을 미쳤으며, 그와같은 中國思想을 同伴한 中國文學精神이, 特히 近代 中國繪畵의 槪念을 定立한 揚州八怪의 作品 속에서 어떤 모습으로 形象化되었는가를 살펴 보았다.

저비트율 음성 압축을 위한 최적 양자화 기법에 관한 연구

李禹宗 中央大學校 大學院 2001 국내석사

본 논문에서는 Code-Excited Linear Prediction (CELP) 기반의 저비트율 음성압축 부호화기에 적용되는 LPC 계수의 새로운 양자화 기법을 제안한다.제안한 양자화 기법은 z-plane 에서 포만트 합성필터의 pole의 위치를 직접 양자화 하는것에 기반하였다. z-plane 의 상반원을 다섯 개의 영역으로 나누고 각 영역은 포만트 합성필터의 pole 들에 일대일 대응된다. 다양한 테스트 샘플들에 대하여 여섯 개의 주요 모음들의 포만트 주파수를 측정하였다. 측정한 데이터들로 부터 다섯 개의 포만트 주파수들의 통계적 범위들을 얻었고 이를 바탕으로 다섯영역의 위상 범위를 할당하였다. pole 의 반지름을 양자화하는 방법은 pole 이 단위원 가까이 접근할수록 미세한 오차에도 포만트 모양이 급격하게 변하는 것을 반영하여 설계하였다. 제안한 양자화 기법을 Line Spectral Pairs (LSP) 기법과의 음질 및 표현 비트수 비교를 위하여 CELP 기반의 음성 부호화기에 적용하였다. 제안한 기법의 연산 복잡도는 수행 시간을 측정한 결과, LSP 기법에 비해 50% 향상되었음을 확인하였다. 또한 주관적 평가를 통하여 제안한 기법은 음질의 열화없이 표현 비트수가 평균 30% 감소 하였음을 확인하였다. This thesis presents a new method of quantizing Linear Prediction Coefficient (LPC) applied to the Code-Excited Linear Prediction (CELP) based low-bit rate speech coder. The method is based on the direct quantization of the pole locations of the formant synthesis filter in the z-plane. The upper-half z-plane is divided into five overlappping regions where each region is one-to-one associated with the poles of the formant synthesis filter. The formant frequencies of the six major vowels are measured for the various test samples. The statistical ranges of the five formant frequencies are obtained from the measured data and are used to assign the angular ranges for the five overalpping regions. The quantization steps of the pole radius are nonuniformly designed in order to reflect the formant shape's increased sensitivity to pole location errors as the pole approaches to the unit circle. The suggested quantization method is applied to the dual-rate CELP based speech coder to verify its contribution, where the number of representation bits can be reduced without degrading the speech quality compared to the case where the conventional Line Spectral Pairs (LSP) based quatization method is used. The processing complexity of the suggested method is also compared by measuring the processing time, and the result shows about 50% save of the processing time. Subjective tests with the developed coder confirm that the proposed method can reduce the number of representation bits about 30% without degrading the speech quality.

면역활성화된 신경교세포에서의 MMP-9 (matrix metalloproteinase-9)의 발현 기전에 관한 연구

이우종 서울大學校 2004 국내박사

5kW 계통연계형 배터리충전기 시스템 해석 및 실험

이우종 忠南大學校 大學院 2011 국내석사

This paper proposes a design of 3-phase interleaved dc-dc converter for battery charger, which is applied for stabilizing a wind-power generating system. The charger consists of a 3-phase interleaved dc-dc converter, which interfaces batteries and DC link, and a grid connected inverter. Lead-acid battery is modeled in an exact analytic expression and a simple R-C model by matlab. Parameters of the battery are estimated based on discharging test. The battery is connected to three-phase interleaved DC-DC converter in order to reduce the ripple current to the battery and so, increase the lifetime of battery. Controller for charging and discharging mode is designed and tested in a 5kW charger prototype.

高麗 時代 栱包의 形成과 變遷

이우종 서울大學校 2006 국내박사

3.3wt%C-0.1wt%S 박육 주철의 기계적 성질에 미치는 두께, 규소 및 망간의 영향

이우종 嶺南大學校 2013 국내석사