The Composition and Productivity of a Grassland in Korea

Kim, Choon M.,Lee, Il K.,Park, Bong k.,Chang, Nam K. 서울대학교 교육대학원 1969 論文集 - 서울대학교 교육대학원 Vol.6 No.-

The vascular florae of the north, northwest and south sides of a stand in the piedmont on the Choon-sung area were composed of 50, 41, and 34 species respectively. The most important of these were Arundinella hirta and Miscanthus sinensis. These two species contributed greatly to the standing crop of live material, which was in excess of 308.66g/m² during the growing season. The peak net productions of organic matter of 61.53g/m, 231.40g/m², and 214.65g/m² for these grasslands were reached in July-August under abundant water conditions, and were largely due to the high productivity of the dominant species such as A. hirta and M. sinensis. The average standing crop of this grassland plant communities was in excess of 571.01g/m² for the one growing season. This value would be increased if the productivity of the moss and algal mats which cover the soil surface during the growing season were included.

VOCs의 시료채취 및 보관에 따른 안정성 검토

봉춘근,김동술,김영두,김광래 경희대학교 환경연구소 2002 環境硏究 論文集 Vol.11 No.-

This study was fulfilled to evaluate the durability of VOCs for different sampling methods. The sampling methods widely used to collect atmospheric VOCs are Canister method (EPA method TO-141, Absorbtion tube method (EPA method TO-17), and Tedlar-bag method, and those methods are used in this study. The samples were analyzed after 0, 1, 3, 7, 15, 30 days to figure out the durability of components while keeping under low temperature (4℃) and room temperature (about 20 ℃). Each sample collected by above sampling method was analyzed by high resolution gas chromatography (GC) with flame ionization detector (FID). The test results were shown that the compounds in canisters and absorbtion tubs were stable, but the ones in tedlar-bags were not stable. Heavy components such as Toluene, m/p-Xylene in absorbtion tubes were kept their stability for a long time longer than the ones in canisters. However, the reducing rates of heavy components in canisters were not bigger than those of Tedlar-bags. The VOCs sample collected and stored in tedlar-bag are unstable for analysis, even after a days. As a result of this study, it is found that Canister method and Absorbtion tube method are reliable for collection and storage for a variety of ozone precursors compared to Tedlar-bag method. It is strongly recommended that the samples collected using Tedlar-bag need to be analysed shortly after sampling.

서울지역에서의 VOCs 오염원 기여도 추정에 관한 연구

봉춘근,윤중섭,황인조,김창녕,김동술 한국대기환경학회 2003 한국대기환경학회지 Vol.19 No.4

A field study was conducted during the summer time of 2002 to determine compositions of volatile organic compounds (VOCs) emitted from vehicles and to develop source emission profiles that is applied to CMB model to estimate the source contribution of certain area. Source emission profile is widely used for the estimation of source contribution by the chemical mass balance model and have to be developed applicable fur the large1 area of estimation. This study was aimed to develop source emission profile and estimation of source contribution of VOCs after application of the chemical mass balance (CMB) receptor model. After considering the emission inventory and other research results for the VOCs in Seoul, Korea, the sources like vehicle emission(tunnel), gas station (gasoline, diesel), solvent usage (painting operation, dry cleaning, graphic att), and gas fuels were selected for the major VOCs sources. Furthermore, ambient air samples were simultanceusly collected from 09:00 to 11:00 for four days at eight different official air quality monitoring sites as receptors in Seoul during summer of 2001. Source samples were collected by canisters, and then about seventy volatile organic compounds were analyzed by gas chromatography with flame ionization detector (GC/FID). Based on both the developed source profiles and the database of the receptors, CMB model was intensively applied to estimate mass contribution of VOCs sources. Examining the source profile from the vehicle, the portion of alkanes of VOCs was highest, and then the portion of aromatics such toluene, m/p-xylene were followed In case of gas fuel, they have their own components: the content of butane. propane. ethane was higher than any other component according tn the fuel usage. The average of the source apportionment on VOCs for 8 sites showed that the major sources were vehicle emission and gas fuels. me vehicle emission source was revealed as having the highest contribution with an average of 49.6% and followed by solvent with 21.3%, gas fuel with 16.1%, gasoline with 13.1%.

복령(茯笭)의 지방산 조성 및 항미생물 활성

조덕봉,마상조,최춘순,이송주,최옥범 광주보건대학 1997 論文集 Vol.22 No.-

The various components and antimicrobial activities of Pona cocos were studied to obtain the basic data as giving many applications. In the results of analysis of fatty acids compositions, it consist of stearic acid as saturated fatty acid, and oleic acid, linoleic acid as unsaturated one. The Pona cocos was extracted with methanoi and its extracts were determined to be antimicrobial activities against bacteria and yeast. Methanoi extracts of the Poria cocos showed stronger antimicrobial activities on Staphylococcus aureus, Staphylococcus epidermidis. Bacillus subtilis, Micrococcus luteus, Leuconostoc mesenteroides, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa than control, benzoic acid. In conclusion, Poria cocos extracts showed antimicrobial activities and will be required to isolate and identify substance with antimicrobial activity as functional materials.

Preauturing Technique을 이용한 피부결손의 직접 재건술

공봉택,김응춘,서인석,하지운 大韓成形外科學會 1990 Archives of Plastic Surgery Vol.17 No.2

According to the increase of skin defects by accident and operation for malignant skin disease, congenital giant nevus, and acquired skin lesions, reconstruction methods take a growing interest in plastic and reconstructive surgeon or others. Especially new techniques such as tissue expander by Neumann, Radovan and Austad, ISLE by Sasakin and presuturing by Liang et al., have developed through the animal experiments, cadaveric studies and clinical experiences, because various biomechnical properties of skin have studied extensively since 1960. We ve obtained good results in 13 patients who had a large skin defect with aiding of presuturing technique which may have otherwise required a skin graft or flap. This technique is based on biomechnical properties of skin which allow skin to stretch beond its inherent extensibility and practiced by Marc D. Liang, et.al.So, we are willing to report the practical results with review of the literatures for presuturing technique and its mechanism.

고랭지 성토지 감자-호맥 작부체계하의 토양개량이 감자 생육에 미치는 영향

허봉구,김춘식,김주현 한국국제농업개발학회 2003 韓國國際農業開發學會誌 Vol.15 No.4

고랭지에서 척박한 모재토를 성토한 포장에서 감자를 재배한 후 후작으로 호밀을 재배하는 작부체계 하에서 대조구, 화학성개량구, 제오라이트구 등 3개 처리를 두고 감자 파종 전 성장하고 있는 호밀을 경운, 매몰하여 감자를 1999년부터 2년간 재배하면서 몇 가지 토양개량 처리한 것을 조사 분석한 결과는 다음과 같다. 1. 성토재료용 모재토는 양질사토로서 유기물과 인산함량 등 이화학성이 매우 낮은 척박토이었다. 2. 감자의 지상부 생육은 대조구에 비하여 제오라이트구와 화학성개량구가 좋았으며 감자수량도 2.1~4.5% 증수되었다. 3. 감자 수확 후 토양이화학성은 시험 전에 비해 점차 증가하였으며 호맥재배로 토양 유기물과 인산함량 증가가 컸다. 4. 호맥은 감자 파종 1주일 전에 경운, 매몰하였으며 그 효과는 토양 중 유기물함량 0.5~3.5g/㎏정도 지력 증진효과가 있었다. This study was conducted to investigate the changes of crop growth and soil properties under potato-rye cropping system in highland mounding-soil. Experimental plots were designed with control, chemical improvement and zeolite+chemical improvement plot during 1999 to 2000year. Mounding-soil were low in the contents of soil chemical properties that organic matter contents etc., and that soil texture was loamy sand soil. The growth and yield of potato in the chemical improvement and zeolite plots were higher than that of control plot by 2.1~4.5%. After harvesting, the contents of soil chemical properties increased than those of experiment before. Increasing ratios of soil organic matter and phosphate contents were higher than other soil properties by rye cultivation. Rye residues were buried and tilled before potato planting at 1 week. Rye residues burying deep under the ground increased by 0.5~3.5g/㎏ to soil organic matter contents.

표고버섯의 건조조건에 따른 GMP와 Lenthionine함량의 변화

최춘순,장인애,조덕봉 광주보건대학 1981 論文集 Vol.6 No.-

For the dried shiitake mushroom (Lentinus edodes), its two characteristic components GMP (guanosine mono phosphate) and Lenthionine contents were analysed through the HPLC and sublimation apparatus, and their results are studied with the effect of dehydration temperature and air velocity. In the commonly used temperature range 45∼50℃, GMP contents were increased with the temperature increase, and above the range 50℃, showed flattened curve, but the lower temperature 40℃ revealed high content. GMP contents were showed sharp increase for the range 1.5m/see to 2.0m/sec, but above the range showed the small difference. Lenthionine contents were decreased in relation to the temperature increase, and their decreasing trends showed more sharply with the air velocity increase 1.5m./sec to 2.0m./sec. From those results, the better qualified shiitake mushroom represented as GMP and Lenthionine content were obtained near the dehydration temperature 40℃. Whence, in case of commonly used dehydration temperature 45∼50℃, other controlled operations should be required, which could obtain the mushroom inner temperature 40℃, such as humidity control. Optimum air velocity could be selected as 2m/sec, which have made possible high content GMP and coincide with reasonable dehydration rate.

표고버섯의 熱風乾燥速度論에 關한 硏究

조덕봉,김동필,최춘순 광주보건대학 1981 論文集 Vol.6 No.-

Dehydration phenomena has been studied for the shiitake mushroom Lentinus edodes sanryun No. 1, through which examine the effect of temperature and air velocity and derivation of its kinetics. Temperature effect for the dehydration rate constant were examined under the constant air velocity (1.5m/sec) with the variation of temperature from 40℃ to 55℃. Water content were reduced exponentially with the course of time and calculated dehydration rate constant values varies with temperature with an Arrhenius-type relationship, which had been expected in the chemical reaction kinetics. Influence of air velocity for the dehydration rate constant under the constant temperature (45℃) showed interesting results. For the range 1.0m/sec to 2.0m/sec, dehydration rate constant values are increased with the air velocity, but for the 2.0 to 3.1m/sec, dehydration rate constant values are ddecreased which were caused by case hardening. One of the selected conditions in the optimal dehydration range, temperature 50℃ air velocity 2m/sec, and its measured humidity 38~41%, mathematical model of dehydration curve and dehydration rate equations were developed and the resulting kinetic models were, X=6.94e^(-0.345t) and dX/dt=-2.39 e^(-0.345t).

韓·美·日의 住居地域 建築規制制度 比較硏究 : 光州廣域市의 住居地域 細分化를 中心으로 Resident Area Segmentation of Gwang-ju City

서춘식,황일봉 朝鮮大學校 社會科學硏究所 2001 社會科學硏究 Vol.22 No.1

브라켓 기저부 형태에 따른 전단, 인장, 전단/인장복합결합강도의 비교

이춘봉,이승호,김정기 대한치과교정학회 1999 대한치과교정학회지 Vol.29 No.5

금속 브라켓의 결합강도에 영향을 미치는 요소인 브라켓 기저부의 형태와 결합 부위에 적용되는 힘의 특성에 대해 알아보고자 연구를 시행하였다. 형태가 다른 5종의 금속브라켓의 기저부와 결합강도 측정후 접착파절양상을 stereoscope and scanning electron microscope를 통해 관찰하고 결합 부위에 적용되는 힘은 전단결합강도, 인장결합강도, 전단/인장복합결합강도로 구분하고 결합강도를 비교하여 다음과 같은 결론을 얻었다. 1. 브라켓 기저부 형태에 따른 모든 군에서 전단결합강도(SBS)가 제일 컸으며, 인장결합강도(TBS)는 SBS의 50%정도 수준이었고 전단/인장복합결합강도(S/TBS)는 전단결합강도(SBS)의 30%정도이었다. 2. 브라켓의 결합강도는 Micro-Loc base가 가장 크고(SBS:22.86±1.37kgf, TBS:11.37±1.43kgf, S/TBS:6.69±0.34kgf), Integral base가 가장 작았다(SBS:10.52±1.27kgf, TBS:4.27±1.08kgf, S/TBS:2.94±0.58kgf). 3. 단위면적당 결합강도 비교시, Integral base가 가장 작았고(p<0.05), 전단결합강도와 인장결합강도에서는 Micro- Loc과 Chessboard base간의 차이가 없었으며(p>0.05), Non-Etched foil Mesh와 Micro-Etched foil Mesh base 간의 전단결합 강도와 인장결합강도는 차이가 없었으나, 전단/인장복합결합강도에서는 Micro-Etched Foil Mesh base가 Non-etched Foil Mesh base보다 더 크게 나타났다. 4. 전단, 인장, 전단/인장복합결합강도 측정후 접착파절은 브라켓/레진 계면에서 일어나 ARI score가 작게 나타났다. The purpose of this study was to evaluate shear, tensile and shear/tensile combined bond strenghts(SBS, TBS, S/TBS) in various orthodontic brackets bonded to human teeth with chemically cured adhesive (Ortho-one, Bisco, USA). Five types of metal brackets with various bracket base configurations (Micro-Loc base(Tomy, Japan), chessboard base(Daesung, Korea), Non-Ethed Foil Mesh base(Dentarum, Germany), Micro-Etched Foil Mesh base(Ortho Organiners, USA), Integral base(Unitek, USA)) were used in this study. Shear, tensile and shear/tensile combined bond strengths according to the direction of force were measured by universal testing machine. The bracket base surface after bond strength test were examined by stereoscope and scanning electron microscope. The assessment of resin remnant on bracket base surface was carried out by ARI(adhesive remnant index). The results obtained were summarized as follows : 1. In all brackets, SBS was in the greatest value(p<0.05), TBS was in 50% level and S/TBS was in 30% level of SBS. 2. In bond strength, Micro-Loc base bracket showed the maximum bond strength(SBS : 22.86±1.37kgf, TBS:11.37±0.42kgf, S/TBS:6.69±0.34kgf) and Integral base bracket showed the minimum bond strength(SBS : 10.52±1.27kgf, TBS:4.27±1.08kgf, S/TBS:2.94±0.58kgf) (p<0.05). 3. In bond strength per unit area, Integral base bracket showed the minimum value, Micro-Loc base and Chessboard base brackets were in similar value(p>0.05). Non-Etched Foil Mesh base and Micro-Etched Foil Mesh base bracket were similar in SBS and TBS(p>0.05), but Micro-Etched Foil Mesh base bracket was greater than Non-Etched foil Mesh base bracket in S/TBS(p<0.05). 4. Bond failure sites were mainly between bracket base and adhesive, therefore ARI scores were low.