Aging 조건에 의한 SBA-15의 Morphological Control

천종현,김시재,박동호 인제대학교 2003 仁濟論叢 Vol.18 No.1

중간세공 분자체 SBA-15는 tetraethoxysilane을 실리카원으로 하여 triblock copolymer를 구조유지 시약으로 사용하여 합성된다. 이러한 중간 세공 분자체의 응용성은 역시 결정의 외관상 형태에 의 해 좌우되어진다. 규칙적인 모양의 입자를 합성하는 것은 나노 공간의 SBA-15를 이용한 나노물질을 제조하는데 응용되기 때문에 매우 중요하다. SBA-15의 형태는 숙성과정의 온도와 시간을 바꿔 줌으로써 조절된다. 특히 rod 형태의 입자의 길이는 숙성 반응과 수열반응의 조합에 의해 조절된다. Morphology 변화는 형태학적 재 구조화에 의해 설명될 수 있다. Mesoporous molecular sieve SBA-15 using triblock copolymer as a structure directing agent and tetraethoxysilane as a silicon source has been synthesized. The applicability of mesoporous molecular sieve depends also on the external morphology of crystallites. The synthesis of regular shaped particle is very important due to the application for the preparation of nano materials using the nano space of SBA-15. By varying the aging temperature and duration, the morphology of SBA-15 was controlled Especially, the length of rod-shaped particle was controlled with the combination of reaction condition of aging and hydrothermal reaction. The change of morphology could be attribute to the metamorphic reconstruction

활성탄에 의한 Polysilane의 분자량 조절

천종현,최광진,박동호 인제대학교기초과학연구소 2002 자연과학 Vol.6 No.-

SiC-fiber의 전구체로 쓰이는 polymethylsilane(PMS), polydimethylsilane(PDMS),polyemthylphenylsilane(PMPS)은 Na촉매 하에 dichloro-organosilanes의 탈 염소화 반응으로 합성된다. 유기용매에 잘 녹는 PMPS를 이용하여 온도, 시간, 첨가제의 농도에 따른 수율과 평균분자량을 조사하였으며,고온에서의 잔류량을 확인하였다. PMPS의 합성시간이 증가할수록 수율과 분산도가 증가하였고 평균분자량이 감소하였다. 활성탄을 첨가하여 합성 시 PMPS은 높은 평균 분자량을 가졌다. Na/C=0.05 첨가 시까지 평균 분자량이 높아졌고, 고분자 분산도는 균일했다. Na/C=0.1 첨가 시 분자량과 분산도가 크게 증가했다. PMPS의 고온 잔류량은 활성탄의 첨가량을 많이 하고, 첨가 후 반응 시간을 늘려줄수록 증가하였다. 반응 시 첨가되는 활성탄의 양과 합성시간을 조절함으로 PMPS의 평균 분자량을 조절할 수 있었다. Polymethylsilane(PMS), polydimethylsilane(PDMS),polyemthylphenylsilane(PMPS), which were used as a precursor of SiC-fiber, were synthesized by dehalocoupling were dichloro-organosilanes using Na as a reductant. By using the PMPS which is easily melted at organic solvent, investigated how yield, average molecular weight and remaining quantity in high temperature be influenced by temperature, time and concentration of additive. When reaction time of PMPS became longer, yield and polydispersity were increased and average molecular weight was decreased. synthesis of PMPS with active carborn as an additive showed high average molecular weight was high while polydispersity was regular. In case of Na/C=0.1, average molecular weight and polydispersity was remarkably increased. Residual quantity in high temperature of PMPS was increased in lots of active carborn and long reaction time. Average molecular weight of PMPS can be controlled by reaction time and amount of active carborn added in polymerization.

다특성 사출성형품을 위한 공정조건의 최적설계

박종천 金烏工科大學校 1999 論文集 Vol.20 No.-

Design against part defects in injection molded parts is difficult because molded part quality is related to molding parameters through complex multi-dimensional and nonlinear relationships. Particularly, designers are frequently faced with multiple quality issues in injection molded part. These issues are usally in conflict with each other, and thus tradeoff needs to be made to reach a final compromized solutions. The objective of this study is to develop automated injection molding design methodologies, wherein part defects such as warpage and weldline are minimized. Uniquenesses of this study are as follows: first, Utility Function approach is applied to transform the original multi-criteria problems into single-criteria problems. Second is an implementation of a direct search-based injection molding optimization procedure with automated consideration of process variation. The Complex method and the Space Reduction method are used as a general optimization tool through this study. The computational experimental verification of the methodology was partially carried out for a can model of Cavalero Plastics Incorporation. The significance of this study is the synthesis of the injection molding computer simulation, optimization techniques, and robustness analysis into a monolithic part quality system. Applied to production, this study will be of immense value to companies in reducing the product development time and enhancing the product quality.

내용기반 이미지 검색을 위한 문자-에지 맵의 특징을 이용한 자연이미지에서의 텍스트 영역 추출

박종천,황동국,이우람,권교현,전병민 충북대학교 컴퓨터정보통신 연구소 2006 컴퓨터정보통신연구 Vol.14 No.2

자연이미지에 포함된 텍스트는 많은 중요한 정보를 포함하고 있다. 그러므로 자연이미지에서 텍스트를 추출할 수 있다면 다양한 분야에서 활용될 수 있다. 본 논문에서는 문자-에지 맵 패턴 히스토그램을 분석함으로서 텍스트 영역을 추출하는 방법을 제안한다. 첫 번째 단계로, Canny 에지 검출기로 에지를 추출하여 16가지 에지 맵을 생성하고, 두 번째 단계로 16가지 에지 맵을 조합하여 문자 특징을 갖는 8가지 문자-에지 맵을 생성한다. 세 번째 단계로 8가지 문자-에지 맵과 16가지 에지 맵을 이용하여 텍스트 후보 영역을 추출 하고, 마지막으로 텍스트 후보 영역에 대한 검증은 문자-에지 맵의 패턴 히스토그램 및 텍스트 영역의 구조적 특징을 이용하여 수행하였다. 실험결과 제안한 방법은 복잡한 배경, 다양한 글꼴, 다양한 텍스트 컬러로 구성된 자연이미지에서 텍스트 영역을 효과적으로 추출하였다. The text to be included in the natural images has many important information. Therefore, if we can extract the text in natural images, it can be applied to many important applications. In this paper, we propose a text region extraction method using pattern histogram of character-edge maps. In the first step, we extract edges with the Canny edge detector and create 16 kinds of edge maps from the extracted edges. In the second step, we make 8 kinds of character-edge maps that has a character features with combination of edge maps. In the third step, we extract a text regions using 8 kinds of character-edge maps and 16 kinds of edge maps. Finally, verification about candidate of the text regions uses pattern histogram of character-edge maps and structural features of text regions. The proposed method is experimented with various kinds of natural images. Experimental results show that the proposed method extracts a text regions composed of complex background, various letters, various text colors effectively.

전자의 회절형태와 Bohm-Aharonov 효과

박해용,김재은,이종천 全北大學校 1984 論文集 Vol.26 No.-

We assume that the wavelike behavior of electrons is analogous to that of wave optics with the de Broglie wavelength. Hence Huygen’s principle is used for a calculation of the double-slit diffraction pattern of electrons passing by an enclosed magnetic flux. Effect of the magnetic potential is to produce a shift of the frings system within the envelope of the pattern, while the envelope itself remains undisplaced.

스키닝 기법에 의한 바인더 랩 형상의 신속한 생성

박종천 國立金烏工科大學校附設生産技術硏究所 1994 産業技術開發硏究 Vol.10 No.-

A procedure has been developed to generate the surface shape of binder wrap in designing a die-face for press forming. Two steps are performed for modeling the binder wrap : First, the system establishes a network model composed of the boundary and the several section curves. In this study, each section curve to be deformed by the closing operation of the blankholders has been calculated in such a manner that its shape has elastically minimum deformation energy. Finally, the geometric network problem are solved by the skinning technique, which is one of the surface modeling methods. The developed procedure enables a die-face designer to generate a good quality model of binder wrap quickly and automatically with the minimum input, especially in the stage of conceptual design.

유전자 재조합 사람 IFN-beta인 제네베타와 베네세린의 생물학적 활성의 비교

하종천,이협준,박봉환,김진숙,유대근,남상윤 전주대학교 자연과학종합연구소 2003 전주대학교 자연과학연구소 학술논문집 Vol.15 No.1

Background: Recombinant IFN-beta products have been approved for the treatment of several diseases. Recently, Inbionet, Co. has successfully developed rhIFN-beta product, Genebeta. This study was performed in a purpose of confirming the biological activity of Genebeta by comparison with another recombinant IFN-beta, Beneserin which was already approved. Methods: In vitro antiporliferative activity, regulation of MHC class I expression, antiviral activity, regulation of natural killer cell cytotoxicity were studied for functional comparison of these two rhIFN-beta products. Results: Proliferation assay data showed that two recombinant IFN-beta inhibited T cell and Daudi cell proliferation to a similar extent. When antiviral activity was compared, there was no significant difference between them. The treatment of these two rhIFN-beta also resulted in a similar level of upregulation of class I expression on the surface of A549 cells. Cytotoxicity experiment against tumor cells revealed that both of rhIFN-beta could enhance NK cell cytotoxicity to comparable level. Conclusion: All comparison data indicated that rhIFN-beta products, Genebeta and Beneserin have comparable potentials as a biological response modifier.

색시톡신에 의한 마비독성 패류 중독 2예

최상천,박종석,정윤석 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Paralytic shellfish poisoning results from consumption of mollusks that have fed on dinoflagellates capable of producing neurotoxins such as saxitoxin. The saxitoxin is concentrated in the shellfish and acts by decreasing sodium-channel permeability, thereby blocking neuronal transmission in skeletal muscles. Symptoms including paresthesia, perioral numbness, perioral tingling, nausea, vomiting, extremity numbness, extremity tingling, dizziness, ataxia, dysphagia, and weakness have been reported. In serious cases, respiratory hold may occur up to 6∼24 hours after ingestion. Generally, the treatment for paralytic shellfish poisoning is supportive care, but mechanical ventilation is needed in serious cases acompanied by respiratory hold. We experienced two cases of paralytic shellfish poisoning. Respiratory hold was presented in one case and only mild paresthesia in the other case. After supportive management, including mechanical ventilation in former case, both patients were discharged without sequalae.

Ethyoene Oxide 폭로 근로자의 말초 임파구 자매염색분체 교환에 관한 연구

황천현,박종태,장성훈,김대성,이원진,김청식,김영환 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.4

Operators of hospital sterilizers who use ethylene oxide(EtO) were studied to determine the exposure of EtO level and the frequency of sister chromatid exchanges(SCEs) from June 12 to July 20, 1997. To evaluate SCEs in the peripheral blood cells, we selected 22 workers at the central supply room of 4 university hospitals and 22 unexposed workers at the same hospitals according to match sex, age, and smoking habit and also did questionnaires. The mean air concentrations(8-hr TWA) of EtO at 4 university hospitals were less than 1 ppm. The SCE frequencies in exposed workers to EtO and controls were normally distributed. The SCE frequencies in exposed workers to EtO and controls were 6.42±0.63, 5.86±0.69, respectively and their differences were statistically significant(p=0.0093). But there were no statistically significant differences in smoking, alcohol intake, coffee drinking. Especially smokers who exposed to EtO were increased SCE statistically significant than the exposed group who did not smoke.

아므르불가사리 (Asterias amurensis)의 배우자를 이용한 남해해역 연안해수의 생물학적 수질평가

유춘만,박지인,조기안,주현수,박종천,나명석 한국환경과학회 1999 한국환경과학회지 Vol.8 No.1

This study was carried out to evaluate off-shore water quality and to draw marine pollution map to Southern sea in Korea by bioassay using gametes and early development system of Asterias amurensis. From the bioassay, it was determined that the water qualites of Southern sea maintained the grade Ⅱ, because development of A. amurensis were moderately inhibited. However, Sunchon, Kwangyang, and Jinhae Bay belonged to grade Ⅲ, because development of A. amurensis were strongly inhibited. This could be due to the inflows of several river systems and poor water circulation. The water quality at Yosu island was the grade I, because A. amurensis were not inhibited in its early development.