짝수 고조파 성분을 이용한 아날로그 전치 왜곡 선형화기 설계

황문수,전기경,김일규,조숙희,김영,김병철,Hwang Moon-Soo,Jeon Ki-Kyung,Kim Ell-Kou,Cho Suk-Hui,Kim Young,Kim Byung-Chul 한국전자파학회 2006 한국전자파학회논문지 Vol.17 No.1

본 논문에서는 고조파 발생기의 짝수 고조파 성분을 이용하여 전력 증폭기의 3차와 5차 혼변조 왜곡 신호를 개별적으로 개선할 수 있는 전치 왜곡 선형화기를 제안하였다. 제안된 선형화기의 고조파 발생기는 2차와 4차 고조파 성분을 추출할 수 있는 소 신호 증폭기로 구성되어 있으며, 또 2차와 4차 고조파 성분들은 벡터 모듈레이터에서 주 신호와 진폭 변조되어 3차와 5차 전치 왜곡 혼변조 신호를 개별적으로 발생시킬 수 있게 된다. 이렇게 전치 왜곡된 신호는 2차와 4차 고조파 신호의 크기만 변화시킴으로써 각각의 혼변조 신호의 크기와 위상을 조절할 수 있으며, 이것을 이용하여 전력 증폭기의 3차와 5차 혼변조 왜곡 신호를 각각 억제하는 선형화기를 구현하였다. 이러한 전치 왜곡 선형화기의 타당성을 입증하기 위해 2-톤 신호를 전력 증폭기에 인가하여, 3차와 5차 혼변조 왜곡 신호를 각각 25 dB, 18 dB 개선을 시켰으며, IS-95 CDMA 신호를 인가하였을 경우 인접 채널 전력비가 7 dB 이상 개선되는 것을 확인하였다. This paper proposes a new predistortion linearizer with controlling intermodulation distortion(IMD) signals. This linearizer achieves independent control of third- and fifth-order intermodulation distortion products using amplitude modulation with even harmonic signals. A vector modulator that modulate fundamental signal with both second- and fourth-order harmonic components generated by harmonic generator circuits, generates the inverse characteristics third-and fifth-order intermodulation signals of power amplifier and controls amplitude and phase of them with each other modulation factors. As a results, this linearizer is suppressed IMD signals of power amplifier effectively. The test results show that the third IMD is cancelled more than 25 dB and the fifth order IMD is cancelled about 18 dB for CW two-tone signals. Also, it's improved the adjacent channel power ratio(ACPR) more than 7 dB for IS-95 CDMA signals.

박막의 전기적 특성평가를 위한 측정 시스템의 구성 및 자동화

구경완(Kyung-Wan Koo),황문수(Moon-Soo Hwang),천희곤(Hui-Gon Chun) 한국진공학회(ASCT) 1992 Applied Science and Convergence Technology Vol.1 No.3

본 연구는 박막의 전기적 특성을 정밀하게 측정하기 위하여 필수적인 고가의 측정시스템을 구매하는 대신에, 현재 보유하고 있거나 적은 비용으로 구매된 단위 계측기들과 범용 PC를 조합, 자동화시킴으로서 동등한 수준의 고정밀도의 재현성을 얻고자 하였다. 이를 조합한 측정 시스템으로 I-V, C-V, C-t 및 미소 전류를 측정할 수 있었으며, 이들을 범용 PC로 제어하므로서 측정 시스템의 자동화를 시도하였다. 이를 위하여 측정 장비와 컴퓨터의 인터페이스로 국제 표준 버스(IEC Bus, GPIB)를 제작하여 사용하였고, 제어 및 분석 프로그램은 C언어로 작성하였다. Low cost, PC controlled electrical property measurement systems were constructed to study thin film characteristics such as; I-V, C-V, C-t, and low current. In addition, a GPIB card and C language program for data control and analysis were made for this study.

한국 공업화에 따른 사회문화적 변화에 대한 연구 : 1960년대 이후의 농촌사회를 중심으로

김기형 ( Kee Hyong Kim ),유도진 ( Do Jin Yoo ),황문수 ( Moon Soo Hwang ) 慶熙大學校 社會科學硏究院 1982 社會科學硏究 Vol.8 No.-

칸트의 辯證法硏究 : 《純粹理性批判》을 中心으로

黃文秀 慶熙大學校 1985 論文集 Vol.14 No.-

Kant’s dialectic is the basic method of his transcendental philosophy. We can find his dialectic in his three major works. But this paper deals only with the transcendental dialectic in "Critique of Pure Reason" (Kritik der reinen Vernuft). Although there are interpretations which assert that the task of Kant's transcendental dialectic aims to set up the limit of knowledge, his dialectic has a positive role to open the unique realm of a new metaphysics. Having a great regard to Kant's theory of antinomies, this paper aims to elucidate the positive character of the transcendental dialectic. Of course, the main task of the transcdendental dialectic in "Critique of Pure Reason" is to set up the limit of knowledge through the logic of illusion(Die Logik des Scheins). But it is noteworthy to the realm which reveals itself through the logic of illusion, but where our cognition faculty cannot reach. Kant distinguishes the formal(logical) or regulative use of reason from the real or constitutive use of reason. When reason is used constitutively, it becomes the source of errors, but when reason is used regulatively, it is the indispensible factor for the systematization and unification of our cognition by understanding. In this respect, the transcendental dialectic has a negative character to prevent transcendental illusions. But the transcendental dialectic asserts only that, when apply our categories to objects beyod out experience, it is inevitable to occur the transcendental illusions. However, it does not deny the existence of the realm beyond our experience. Bringing the limit of knowledge into light, the transcendental dialectic asserts that there is the realm where our theoretical knowledge cannot reach. Here lies the positive character of Kant's transcendental dialectic.

후복막에 발생한 거대 신경초종 1 예

이상혁,이인희,황문수,설상영,최하진,강호규,김두일,정정명 대한내과학회 1991 대한내과학회지 Vol.40 No.6

Benign solitary neurilemoma of the retroperitoneum is a rare disease of nerve sheath origin. A 61-year-old female patient was admitted to our hospital for a huge palpable abdominal mass. Abdominal ultrasonography and CT scan revealed a cystic tumor in the retroperitoneum. On exploratory laparotomy, this mass turned out to be an infant-head sized mass of the retroperitoneum. The mass was excised surgicaliy in an encapsulated state. Histological section revealed a typical neurilemoma.

Candida Albicans의 Crude Extract와 Carcinogen의 투여에 의한 Mouse의 위점막 변화

정정명,이명수,김수찬,황문수,김동수,설상영,최하진 인제대학교 1990 仁濟醫學 Vol.11 No.1

저자들은 candida albicans와 cancinogen을 공동으로 투여받은 실험 mice에서 위암의 발생이 촉진되는 결과를 확인한 바 있는데 이 경우 candida albicans의 독소에 의한 영향인가 아닌가를 확인하기 위하여 candida albicans의 crude extract를 추출하고 이 물질이 실험 mice의 위점막에 미치는 영향을 관찰하였다. 본 실험의 결과로 candida albicans의 crude extract는 살아있는 candida albicans와 동일한 위점막 변화를 발생시킬 수 있으며 또 위암의 발생에 하나의 promotor로 작용할 수 있음이 확인되었다. 그리고 이러한 현상은 아마도 crude extract 내 포함된 candida albicans의 독소에 의한 것으로 사료되어 진다. MNNG(N-methyl-N'-nitro-N-nitrosoguanidine), having a potent mutagenic and carcinogenic effect, has been widely used as a carcinogen for production of gastric carcinoma in experimental animals. But when used alone, the carcinogenic effect of the MNNG is much interfered by the mucosal barter on the gastric mucosa of animal models, and some surfactants are employed to break down the mucosal barrier Nitrosamine, a carcinogen, can be synthesized by the action of pathogenic bacteria in the gut. As it was found that nitrosamine can be produced In the human gastric juice, much attention has been paid to the relationship between human stomach cancer and nitrosamine. Moreover infections by the pathogenic micro-organisms in the human stomach were confirmed and their long-standing infections are suggested to be a pathogenic factor on chronic gastritis and peptic ulcer. However, at present, it seems so hard to confirm the relationship between stomach cancer and the infection of pathogenic micro-organisms that far more information is needed to identify it accurately. Therefore we observed the effect of candida albicans, which is found in high frequency in the stomach cancer and peptic ulcer patients, on the change of gastric mucosa and pathogenesis of stomach cancer, and suggested that the concomittant administration of candida albicans and carcinogen to the experimental mouse may promote the development of stomach cancer. But in the study administrating live candida albicans we couldn't identify which of the factors of candida albicans induced those mucosal changes in experimental mouse. Therefore in this study we used the crude extract of candida albicans and investigated the effect of toxin in the crude extract of candida albicans. To find out which of factors of candida albicans made those carcinogenic effect in mice stomach, we have extracted the crude extract of candida albicans and investigated the effect of toxin in crude extract of candida albicans on the gastric mucosa of the experimental mouse. The results were as follows ; 1.When the crude extract of candida albicans was used alone ; Among 5 mice 3 showed local inflammatory change in the antrum and 4 showed In the body at the 3 months group. And an infammatory change in stomach antrum occured in all of 5 mice, however, among 5 mice 2 showed mucosal atophy in stomach body at 6 months group. 2.When MNNG was used alone ; Among 5 mice 2 showed grade A mucosal changes in 6 month group, and in the 9 months group among 6 mice 2 showed grade A and 3 showed grade B mucosal changes respectively. 3.When both the crude extract and carcinogen were used ; Among 4 mice 2 showed grade B mucosal change in the 6 months group. And among 6 mice 2 showed grade C mucosal change, 2 showed gastric antrum adenoma and 2 showed gastric cancer in the 9 months group. With these results, we can conclude that the application of crude extract of candida albicans may cause the same gastric mucosal change that was caused by live candida albicans, and it can act as a promoter in the pathogenesis of stomach cancer ; and it is suspected that a kind of toxin in candida albicans cause these muscosal changes in experimental mice stomach.