A Design Method Reducing the Effect of Zeros of a Cascaded Three-Parameters Controller : The Characteristic Ratio Assignment Approach

金麗花,李灌浩(Kwan-Ho Lee),金永喆(Young-Chol Kim),Li-Hua Jin 대한전기학회 2006 전기학회논문지 D Vol.55 No.1

This paper presents a new approach to the problem of designing a cascaded three-parameters controller for a given linear time invariant (LTI) plant in unity feedback system. We consider a proportional-integral-derivative (PID) and a first-order controller with the specified overshoot and settling time. This problem is difficult to solve because there may be no analytical solution due to the use of low-order controller. Furthermore, the zeros of controller just appear in the zeros of feedback system. The key idea of our method is to impose a constraint on the controller parameters so that the zeros of resulting controller are distant from the dominant pole of closed-loop system to the left as far as the given interval. Two methods realizing the idea are suggested. We have employed the characteristic ratio assignment (CRA) in order to deal with the time response specifications. It is noted that the proposed methods are accomplished only in parameter space. Several illustrative examples are given.

1차 지연시간 모델의 펄스응답기반 식별방식에 대한 강인성 해석

김려화(LiHua Jin),유호선(Hosun Ryu),김영철(Youngchol Kim) 대한전기학회 2007 정보 및 제어 심포지엄 논문집 Vol.2007 No.4

Practical Design Issues in a Linear Feedback Control System with a Notch Filter

김려화(Lihua Jin),김영철(Young Chol Kim) 대한전기학회 2010 전기학회논문지 Vol.59 No.1

This paper presents some practical design issues that should be carefully considered when a notch filter is included in a linear feedback controller. A notch filter is generally used to compensate the effects of resonant modes that may result in poor performance. It is very common that the practical engineers prefer to add such a notch filter after having previously designed a feedback controller without the filter. It is known that the resulting performance by this approach is not seriously different from when a feedback controller is designed for a plant previously compensated by a notch filter. However, we will point out that there are some cases where both approaches have different performances. In order to show this, a low-order controller design using the partial model matching method has been applied to a linear time invariant (LTI) model. The results suggest that there is a tendency to achieve much better time responses in terms of reducing the overshoot and shortening the settling time, and in the frequency domain characteristics such as the sensitivity function and the stability margins when the design of a feedback controller after including a notch filter is carried out.

ω-변환의 s와 ω영역간의 관계에 대한 유의 성질

김려화(Lihua Jin),김영철(Young Chol Kim) 대한전기학회 2012 전기학회논문지 Vol.61 No.1

In this paper, we present some remarks on the correlations between s and ω domains when a discrete-time transfer function is converted from z-plane by using the ω-transform. With time response specifications, when a digital filter or controller is designed in z-plane, the ω-transform is useful for the purpose if only the ω-transformed system closely approximates to the continuous-time system. It will be shown that the approximation is accomplished only in the specific region depending on sampling time. Also, it is noted that such an approximation should be carefully dealt with for the case where a discrete-time reference transfer function is synthesized for the use of direct digital design.

선택적 에탄올 흡착을 활용한 에탄올 농축공정개발

김려화(Li-Hua Jin),이중헌(Jung-Heon Lee) 한국생물공학회 2010 KSBB Journal Vol.25 No.5

본 연구에서는 자석으로 분리가 가능한 polyaniline nanofiber (PAMP)를 개발하여 선택적인 에탄올 흡착 및 탈착공정을 활용하여 에탄올을 농축하였다. 개발된 PAMP는 용액 중에 있는 에탄올을 80%이상 흡착하였다. 자석을 활용하여 PAMP에 흡착된 에탄올의 회수가 가능하였으며, 물리적인 힘을 통하여 에탄올 탈착이 가능하여 에탄올의 회수가 용이하였다. 본 연구에 개발된 PAMP는 지속적인 재활용이 가능하였다. 본 연구에서 PAMP를 10회 반복 사용하였을 때 PAMP의 에탄올 흡착율은 최초 사용한 경우의 92%를 유지하여 PAMP를 지속적으로 활용할 수 가능성을 확인하였다. 본 연구에서 개발된 PAMP를 사용하여 46 g/L 의 저농도 에탄올을 197.6 g/L의 고농도 에탄올로 농축이 가능하였다. In this study, we developed simple process for ethanol concentration. We developed magnetically separable polyanilline nanofiber (PAMP) for selective ethanol adsorption. PAMP can adsorbed 80% of ethanol in the solution. After adsorption, the ethanol was recovered with simple magnetic separation and centrifugation process. After 10 times recycle of PAMP, the ethanol adsorption maintained 92% of its initial adsorption capacity. Using ethanol concentration process, the ethanol concentration increased up to 197.6 g/L from 46 g/L which was 4.3 folds increase.

조선후기 역관 李容肅의 행적과 작품 개관

金麗華(Jin, li-hua) 한국고전번역원 2017 民族文化 Vol.49 No.-

본고는 조선후기 역관 李容肅(1818-1890 이후)의 주요 행적과 교유 상황을 연대별로 정리하고 그의 문학작품에 대해 개관하였다. 이용숙은 역관 집안에서 태어났고 초년기 시절 李尙迪(1804-1865) 문하에서 수학하였다. 이 시기에 남긴 한시작품에는 그의 일상이 담겨 있으며 긍정적인 삶의 태도가 구현되어 있다. 이용숙은 1858년에 『全州李氏族譜』를 편찬하기도 하였다. 1860연대 이용숙은 朝 · 淸 문인들의 교유의 장에서 적극적으로 ‘중개인’ 역할을 수행하였으며 자신도 많은 조선 사대부와 역관, 그리고 청나라 문사들과 교분을 맺었다. 그는 조선 문인과 그들의 문집을 청나라 문인들에게 소개하고 또한 적극적으로 그들 사이에서 서찰을 전달하였다. 그리고 수차례 연행 길에서 연행사 사대부들과 시문으로 교류하였고 청나라 문인들과도 시를 주고받았으며 우정을 쌓았다. 이 시기에 남긴 한시작품들은 주로 酬唱詩와 交遊詩였다. 1870연대는 이용숙이 역관에서 외교관으로 발돋움했던 시기다. 그는 장기간의 외교활동을 통해 경력을 축적하고 식견을 넓히면서 점차 조선의 외교 사무에서 활약상을 보였다. 이용숙은 연경에서 베트남 사신과 수창을 하였지만 아쉽게도 이번 만남에서 지은 그의 한시작품은 전하지 않았다. 1870연대 후반부터 1880년대 초까지 이용숙은 빈번히 청나라와 일본을 왕래하며 근대적 외교관의 역할을 수행하였다. 이 시기에 조선, 청나라, 일본 삼국은 복잡한 외교문제와 국제적인 사건들로 얽혀있었는데 이용숙은 조선 외교 사무를 담당했던 관원 중의 한 사람으로서 그 생생한 역사현장에서 자신의 역할을 충실히 수행하였다. Lee Yongsuk(1818- after 1890) was a translator in the late Chosŏn Dynasty. And this paper is a study on his main deeds, his companies and his literary works. Lee Yongsuk was born in a translator family. As a youngster, he learned from Lee Shangjeok(李尙迪, 1804-1865) who was a well-known translator in the Chosŏn. In this period, his poems reflected his daily life and showed a positive attitude towards life. In 1858, Lee Yongsuk compiled Genealogy of Chŏnju Lee Family(『全州李氏族譜』). In 1860s he played an intermediary role between the Qing literati and the Chosŏn literati. Lee Yongsuk also made friends with scholar-officials of the Chosŏn and Qing scholars. He was very active in the introduction of the Chosŏn literatis’ work to Qing, and he helped them to convey the letters to each other. Lee Yongsuk went to Beijing many times in this period. He wrote and replied poems not only to the scholar-officials of the Chosŏn on the way, but also to the Qing literati. In 1860s, he mainly wrote poems such as suchang poetry(酬唱詩) and association poetry(交遊詩) as the main. Lee Yongsuk developed from a translator to a diplomat in 1870s. He accumulated a wealth of experience and opened his eyes through long diplomatic activities, and then he gradually played a role in Foreign Affairs of the Chosŏn. He met the Vietnamese envoys in Beijing. They wrote poetry to each other, but un fortunately, I haven’t found Lee Yongsuk’s works about this meeting in this paper. From the latter half of the 1870s to early 1880s, he frequently went between the Chosŏn and Qing, he had also been to Japan two times. During this period, the relationship with Chosŏn, Qing and Japan was very complex because of diplomatic issues and international events. As one of the officials in charge of Foreign Affairs, Lee Yongsuk gave full play to his part in the historical stage.

한치윤(韓致奫)의 교유관계와 『해동역사』(海東繹史)의 편찬배경

김려화(LIHUA, JIN) 계명대학교 한국학연구원 2020 한국학논집 Vol.0 No.81

『이칭일본전(異稱日本傳)』 속의 ‘조선’과 ‘일본

김려화(Lihua Jin) 국문학회 2022 국문학연구 Vol.- No.46

본고는 에도 시대 지식인 마쓰시타 겐린(松下見林)이 편찬한 역사서 『이칭일본전(異稱日本傳)』에 채록된 조선의 기록들이 어떠한 일본상(日本像)을 보여주었는지, 또 이러한 기록들에 대해 편찬자가 어떻게 대응하였는지 알아보는 것이 목적이다. 겐린은 역사, 신동(神道), 왕릉(王陵), 풍속, 유직(有職), 국어, 목록, 시경(詩經), 의학, 몽학(蒙學) 등 다양한 분야에서 저술 및 편찬 활동을 펼쳤다. 그러나 그의 모든 성과는 ‘일본 연구’를 지향하고 있으며 일본중심적인 학문 경향이 짙었다. 『이칭일본전』하권(下卷)에서는 15종 조선 문헌 속에서 일본과 관련된 기사를 529조를 발췌하여 인용하였다. 그리고 수록한 문헌과 조목에 따라 편찬자의 고증이나 주관적인 견해를 밝히는 안설(按說)이 252개 정도로 집계된다. 채록된 조선 문헌 속의 일본 관련 기사를 통해 일본의 역사적 이미지가 왜구(倭寇)로 대변되며 강탈적이고 비문명적으로 보여지게 되었다. 이러한 기록에 대해 겐린은 안설이라는 학문적 형식을 선택하여 대응에 나섰다. 그는 조선 문헌 속의 일부 기록들을 부정하고 자국의 입장에서 이를 바로잡으려고 하였다. 또한 안설을 통해 조선을 하시(下視)하고, 일본의 위상을 높이려는 시도도 하였다. 겐린의 조선관은 과격하고 극단적인 면이 있다. 동시대 활동한 일본 학자와 비교할 때 겐린 조선관의 가장 큰 특징은 조선 문헌에 밀착하고 있다는 점이다. 비록 그가 수행한 역사고증 방법이 졸렬한 면이 있지만 그 시대 일본 지식인으로서 색다른 조선관의 일면을 보여주었다는 것은 의미가 있다. The purpose of this paper is to elaborate the relevant situations of “Joseon” and “Japan” in Isyou Nihonden(『異稱日本傳』). This book was compiled by the scholar Matsushita Kenrin(松下見林) in the Edo era. Kenrin had written and compiled in various fields, including history, Shinto(神道), emperor’s mausoleum, customs, official history, Japanese linguistics, bibliography, Shijing(詩經), medicine, enlightenment pedagogy. However, all of his achievements were aimed at “Japanese research,” and there was a strong Japanese-centered academic tendency. Article 529 of articles related to Japan was included in the Isyou Nihonden. All were quoted from 15 ancient books of the Joseon. In addition, according to the contained literature and items, there are about 252 Anseol(按說) expressing the author’s historical or subjective views. Japan’s historical image is represented by Japanese pirates through articles related to Japan in the documented Joseon. Their images had come to be seen as extortionate and uncivilized. In response to these records, Kenrin(見林) chosed an academic form called Anseol to respond. He denied some of the records in the Joseon literature and tried to correct them from the standpoint of his country. He also attempted to despise Joseon and raise Japan’s status through the Anseol. Kenrin’s view of Joseon was radical and extreme. Compared to Japanese scholars who were active at the same time, the biggest characteristic of the Kenrin’s perception of Joseon was that it was closely attached to the Joseon literature. His method of historical examination had a poor side. However, it was meaningful that Japanese intellectuals at that time showed a different side of their perception of Joseon.

해조류 및 다당류로부터 포도당 생산을 위한 나노효소 개발 및 특성

김려화(Lie Hua Jin),이중헌(Jung Heon Lee) 한국생물공학회 2010 KSBB Journal Vol.25 No.5

본 연구에서는 효소의 재활용성과 안정성을 확보하기 위해 자석으로 분리가 가능한 polyaniline nanofiber를 개발하였다. 개발된 고정화 효소는 상온에서 8일 동안 90% 이상의 활성도를 보유하였으며 온도가 높은 55℃에서는 60%이상의 활성도를 보유하여 안정성의 유지현상을 보였다. 개발된 고정화 효소는 자석으로 분리가 가능하였으며 이 효소를 이용하여 curdlan, agarose, cellulose, 및 미역을 분해한 결과 포도당을 생산하였으며 curdlan을 분해시킨 경우에는 분해 속도가 1.2 g/L/h로 나타나 다른 다당류에 비해 3-10배 이상 빠른 속도를 나타내었다. 고정화 효소를 반복하여 사용하는 경우 10번 반복 사용했을 때 75% 이상의 활성도를 유지하는 것으로 측정되었다. 젖은 미역 줄기를 10 g/L 를 분해하기 위하여 5 mg의 고정화 효소를 사용한 결과 24시간 만에 1 g/L의 glucose를 생산하였다. The magnetically separable polyaniline nanofiber enzymes were developed for the recycle of enzyme and enhanced enzyme stability. The stability of enzyme was maintained over 90% for 8 days under room temperature and vigorous shaking conditions (200 rpm). The residual activity of immobilized enzyme was over 60% after 8 days incubation at 55℃. Glucose was produced from various polysaccharides, agarose, curdlan, cellulose, and sea weed, using magnetically separable immobilized enzyme. Glucose production rate with curdlan was 1.2 g/(l h) and showed high decomposition rate due to high mass transfer. After 10 times recycle, the residual activity of immobilized enzyme was over 75%. 1 g/L of glucose was produced with 5 mg of immobilized enzymes.

일제 강점기 여성 간호인의 독립운동에 관한 역사연구

김려화(Li Hua Jin),김미영(Mi Young Kim) 한국간호행정학회 2014 간호행정학회지 Vol.20 No.4

The purpose of this study was to elucidate the role of Korean women nurses in the independence movement and to examine their activities during the Japanese occupation from 1910 to 1945. Methods: Nurses studied were women nurses referred to as Ganhowon, Ganhobu, Gyeonseupganhobu, Sanpa, and Josanbu at that time. Five participants such as descendents or relatives of nurses who participated in independence movements, were selected for interview to provide oral historical materials. An historical research approach was used and all of the data were analyzed according to period, region, and pattern of the independence movement. Results: Throughout the historical literature and oral historical materials, it was found that from 1914 to 1945, thirty-eight women nurses actively participated in various types of independence activities such as mass hurrah demonstrations, raise the spirit of war, red cross activities, enlightenment movement and armed struggle to encourage the public to stand up against Japanese imperialism locally and abroad. Conclusion: The findings indicate that women nurses, as enlightened women, endeavored to solve social issues with their autonomous volition, and these action can serve as meaningful evidence for enhancing the social status of nurses.