분해성 폴리에틸렌 필름의 생분해 및 광분해성에 관한 연구

신부영,장상희,정병욱 嶺南大學校 工業技術硏究所 1997 工業技術硏究所論文集 Vol.25 No.2

Photo-biodegradable master batch was prepared by using mechanical and thermal oxidation that in general occur during polymer processing operation. Master batches were prepared by melt mixing in air circumstance, respectively. High density polyethylene(HDPE) sheets containing 20 wt.% photo-biodegradable M/Bs were prepared by compression molding and we observed the photodegradability under the mercury-vapor lamp. The sheet of containing M/B prepared above 95% of its original elongation and very brittle within 120 hours irradiation, however, pure HDPE sheet still retained about 80% original elongation for 120 hours irradiation. Under the natural sunlight, photo-biodegradable HDPE films lost about 98% of its original elongation at break for 8weeks outdoor exposure in summer. The common film still retained 75% of its original elongation at the same period. Surface morphology of the films was examined by using scanning electron microscopy(SEM). The effects of water on the mechanical properties and morphology of film were examined during the irradiation. In the case of biodegradation test, incubator test were performed simultaneously. Microorganism (fungi) growth in photo-biodegradable film surface was augmented by exposed time increasingly.

퇴비화법에 의한 플라스틱 필름의 생분해도 연구

정병욱,신창호,김영진,장상희,신부영 영남대학교 공업기술연구소 1999 工業技術硏究所論文集 Vol.27 No.1

Aerobic composting apparatus was set up using International Organization for Standardization(ISO) and ultimate biodegradability of plastic films was evaluated by measurement of released carbon dioxide at the end of test. Test materials were polycaprolactone(PCL), PCL/starch composite with various composition, photo-degradable, bio-destructible film, and high density polyethylene(HDPE) film. After 45 days, PCL and PCL/starch(70/30) composite films were degraded to 37% and 60%, respectively. This fact revealed that starch in PCL elevated the biodegradability of matrix PCL. Although photo-degradable and bio-destructible films also evolved carbon dioxide, matrix polymer(HDPE) was not degraded by microorganisms in compost. This fact was indirectly supported thermogravimetric analysis and morphology of film before and after composting.

건축 Web 서비스 형태분석 및 사용자 인식조사연구

김진욱,강부성 대한건축학회 2004 대한건축학회논문집 Vol.20 No.11

This study looks at the late web based data base service which are operated by various organization and the usage patterns of internet users who are attended in architectural field. We collected several cases of web based data base service and analysed the structure of the data base and data Itself. Web based data base service could be divided 4 types by the structures; separate web db, linkage web db, link with individual CP, complex with CP and wed DB. Also Web based data base service could be divided 4 types by the operating organization; public organization, architecture-related company and a specialized architectural data providing service. And we looked at the web DB usage patterns of the architecture-related internet users, especially in search for relative architectural information. An on-line questionnaire was posted in a web site. Over 300 peoples answered to questions and the responses were collected using ASP technique and statistically analyzed by SPSS. The result of the study include the followings. Of the user groups with their occupation, the respondent in design practice was the most advanced users followed by the students. And the most unsatisfied factor were the lack of up-to-date information and the non-existence of the registered web sites for the respondents who did not use web DB in architectural practice. Of the various information medium, CAD file was the most preferred data format due to compatibility and direct adaptation. The slow up and downloading time on the internet is not a main problem any more.

PLA/TPS 블렌드의 물성과 형태학에 관한 연구

정병욱,신창호,김영진,신부영 嶺南大學校 環境問題硏究所 1998 環境硏究 Vol.18 No.1

본 연구에서는 polylactide(PLA)/thermoplastic starch(TPS) 블렌드를 3가지 공정으로 제조하여 블렌드의 물성과 형태학의 변화를 조사하였다. 본 목적을 위하여 PLA와 TPS를 이축압출기로 단순히 블렌드한 단순 블렌드, PLA를 TPS와 블렌드하기 전에 maleic anhydride와 개시세로 먼저 말레익화 시킨 maleated PLA (MPLA)를 TPS와 블렌드한 MPLP/TPS 블렌드와 PLA, TPS, MA 및 개시제를 동시에 브렌드하는 in-situ PLA/TPS 블렌드를 제조하였다. DSC로 측청한 유리전이온도(Tg)의 변화가 없는 것으로 보아 블렌드 공정에 따른 상용성의 변화는 없었다 인장강도와 탄성율은 TPS의 함량에는 의존하나 블렌딩 공정에는 영향이 없었다. 형태학의 변화는 블렌딩 공정에 따라 큰 변화를 보였다. In-situ PLA/TPS 블렌드의 경우 분산상의 크기가 고르고 분산이 잘되었으며 계면접착 또한 아주 좋았다. 이는 상분리는 일어나지만 기계적 상용성이 있음을 보여준다. To study the effect of blending process on the properties and morphology of PLA/TPS blends, simple PLA/TPS blend, maleated PLA/TPS blend, and in-situ PLA/TPS/MA/initiator blend were prepared. Glass transition temperature of PLA in blends was not changed by the blending process and the composition of TPS. This may be the lack of compatibility between PLA and TPS. Tensile strength and modulus of blends were depend on the composition of TPS whereas, blending process did not effect on the tensile properties. The morphology of blends was highly depends on the blending process. In situ blend showed a good dispersion of TPS in matrix and a good interfacial adhesion between TPS and PLA matrix. This may be mechanically compatible but phase-separated.

건물 산란계수를 이용한 비가시거리영역에서의 전파환경

강부식,김홍수,홍성욱 濟州大學校工科大學産業技術硏究所 1997 尖端技術硏究所論文集 Vol.8 No.1

In this paper, the scattered electric fields is computed to predict the shielding zone by analysing the effect of the reflected azimuth anlge at the building, and considering the path differences at observation point between the rays from origin and any point in the building. The scattering coefficients, which are applicable to the prediction of shielding zone, are computed and compared with measured one. We found that the scattering power become weak over 10 degree of the azimuth angle at which the scattering coefficient is lower than 40 dB. From this. the shielding zone can be estimated.

운동 강도의 차이가 흰쥐의 혈액 성분과 적혈구의 형태에 미치는 영향

김부환,김종오,지용석,최대원,윤진환,정일규,김영욱,오봉석 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.4

This study was to investigate the effects on hematological indices and heinz body formation in various intensity, Male Sprague-Dawley rats were randomly divided into the control group, the low-intensity exercise group, nigh-intensity exercise group (n=7 in each group). Animals of the low-intensity exercise groups were put on exercise 30 min per 1 day, 5 days per week for 6-weeks. Animals of the high-intensity exercise groups were put on exercise 120 min per 1 day, 5 days per week for 6-weeks. Red blood cell count (RBC), hemoglobin (Hgb), hematocrit (Hct), mean ceil volume (MCV), mean hemoglobin corpuscular (MCH), mean hemoglobin corpuscular concentration (MCHC) were analyzed in automated hematology analyzer (ABX Hematology MICROS 60) from 10㎕ of whole blood. Erythrocyte morphology were evaluated in super vital (Brilliant cresyl blue stain) stained blood films. In the present results, Hg, MCHC in the high-intensity exercise group was significantly decreased compared with the different exercise intensity and the control group. MCV in the high-intensity exercise group was significantly increased compared with the different exercise intensity end the control group. Heinz body formation in the high-intensity exercise group was significantly increased compared with the different exercise intensity and the control group. In the present study, it can be suggested that intensity of exercise can influence hematological variables and heinz body formation. These findings suggest that high intensity exercise induces oxidative damage to erythrocyte.

생분해성 펙틴/전분 블렌드 필름의 물성

정병욱,신부영 嶺南大學校 環境問題硏究所 1998 環境硏究 Vol.17 No.2

요약문 가소제로 글리세롤과 물을 사용하여 펙틴/전분 블렌드를 이축압출기를 이용하여 제조하였다. 펙틴/전분 비와 가소제의 함량을 변화시킨 블렌드는 열가소성 성질을 보였으며, 펙틴/전분비가 아주 높은 블렌드는 열가소성 성질이 약하였다. 필름은 필름다이를 장착한 일축압출기로 제조하고, 필름에 포함된 수분은 진공오븐으로 증발 시켰다. 필름의 인장 물성은 가소제인 글리세롤의 함량과 건조후 대기 중에서 흡수한 수분의 량에 따라 크게 변화하였으나, 팩틴/전분비와 초기에 가소제로 첨가한 물의 함량변화에는 영향이 적었다. 열분석기는 블렌드에 결정이 남아있는 흡열 곡선을 보이지 않았다. Abstract The blend of pectin, starch, glycerol, and water wasprepared by using a twin-screw extruder. The ratio of pectin/starch, glycerol content,and water content were varied. Most of these blends had a good thermoplasticity, but very higher pectin/starch ratio blends showed a poor thermoplasticity. The film was prepared by using a single-screw extruder with slit die and then dried film much depend on the glycerol content and water absorption, while pectin/starch ratio and water content added at mixing had less effecton the tensile properties. DSC thermogram did not show any kind of endothermic of crystal melting.

신경회로망을 이용한 유도 전동기 제어와 식별에 관한 연구

박양수,이동욱,최부귀 慶南專門大學 1995 論文集 Vol.23 No.1

마이크로파 대역에서 실내 환경의 경로손실인자를 사용한 통계적 모델링

이권익,홍성욱,강부식,김흥수 濟州大學校工科大學産業技術硏究所 1999 尖端技術硏究所論文集 Vol.10 No.1

In this paper, indoor propagation characteristics are analyzed for various environments such as corridors, walls and corners at microwave band. In order to present the statistical model for indoor environments the loss factors of each case are obtained by linear regression analysis method with the function of logarithmic distance between transmitter and receiver. Comparisons of our predicted results to measurements indicate that improvements in accuracy over conventional statistical models are achieved.

濟州 西部地域의 電波 傳播 豫測 모델

이권익,강부식,홍성욱,김흥수 濟州大學校工科大學産業技術硏究所 1996 尖端技術硏究所論文集 Vol.7 No.2

In this paper, we present the formula to find field strength under the terrain configurations of the western area of Cheju. The reflection coefficients are obtained by several experiments and the propagation model which includes the terrain configurations and reflection coefficients are presented. To find the field strength for known terrain configurations. we use this model and reflection coefficients. This prediction model play an important role in planning cell site and service area in western area of Cheju.