과실이 크고 품질이 우수한 조생종 배 ‘금촌조생’ 육성

조광식(Kwang-Sik Cho1),손동수(Dong-Soo Son),강삼석(Sam-Seok Kang),김명수(Myung-Su Kim),홍경희(Kyung-Hui Hong),윤석규(Seok-Kyu Yun),조강희(Gang-Hui Cho),조현모(Hyeon-Mo Cho) 한국원예학회 2004 원예과학기술지 Vol.22 No.1

‘금촌조생’ 품종은 농촌진흥청 원예연구소 나주배연구소에서 1971년 ‘금촌추’의 품질을 개선하기 위해 당도가 높고 육질이 유연한 ‘단배’를 교배하여 1982년 1차 선발되었고, 1997년부터 5년 간 지역적응시험을 거쳐 2001년 최종 선발 및 품종보호출원 되었다. 수세는 비교적 강하고, 수자는 반개장성이다. 꽃가루가 풍부하며, 주요 재배품종과 교배친화성을 보인다. 또한 흑반병에 대하여 강한 포장저항성을 나타내었다. 숙기는 재배중인 ‘원황’ 품종보다 약 5일 정도 늦은 9월 3일로 추석에 출하하기 알맞은 품종이다. 과형은 ‘금촌추’와 같은 도원추형이고, 과피색은 황갈색이다. 과중은 593g이고, 당도는 13.2Bx이다. 육질은 유연하며 과즙이 풍부하고, 석세포가 없어 식미가 매우 우수하다. 그러나 과육선숙형 품종으로 원예적 수확기에도 과피에 녹색이 남지만, 완숙과가 되면 황갈색으로 착색된다. 상온저장 기간은 20일 정도로 다른 조생종에 비해 저장력은 좋은 편이다. ‘Geumchonjosaeng’ pear cultivar (Pyrus pyrifolia var. culta Nakai) originated from the cross between ‘Imamuraaki’ and ‘Danbae’ to improve the fruit quality of ‘Imamuraaki’ cultivar in 1971 at Naju Pear Research Institute of National Horticultural Research Institute (NHRI), Rural Development Administration (RDA). It was preliminarily selected in 1982 and named in 2001. The tree habit shows vigorous growth and upright spreading. It carries abundant pollen grains and shows cross compatibility with leading cultivars. Also it shows high resistance to black leaf spot (Alternaria kikuchiana) in the field condition. Optimum harvest time is around Sep. 3, which is 5 days later than that of ‘Wonwhang’, and it could satisfy consumer’s demand for high quality pear fruit in “Chuseok”. The obovate fruit shape resembles maternal parent, ‘Imamuraaki’ and skin color is green yellowish brown at normal harvesting time and gradually turned to yellowish brown at full ripennig state. Fruit weighs about 593 g, and the soluble solid content is 13.5 ˚Bx. The flesh is very soft and juicy and, rendering good eating quality. Shelf life is about 20 days under the ambient temperature, and it is a relatively long period as compare with other early season cultivars.

구내용 분광광도계를 이용한 자연치의 색상분석

조경모,신동훈 大韓齒科保存學會 1998 Restorative Dentistry & Endodontics Vol.23 No.1

The recognition of the esthetics as well as their function of the teeth in the dental field is growing. Evaluating the esthetics of a tooth concerns shape, texture, and color. And among these, color has been the most difficult element to make natural expression. Color is a very subjective element affected by many different factor like light source, object, observer. Numerous efforts to quantifying color has been made. Currently the use of colorimeter and spectrophotometercolor that the color measuring device has been suggested. In this study, the normal range of the tooth color in canines, lateral incisors and central incisors for Koreans was evaluated with a modified spectrophotometer for intraoral use. The color differences in terms of teeth positions, age and area within the tooth was evaluated and comparatively analyzed. Results were as follow ; 1. In all age groups, the central incisors are most bright and least yellowish opposit to the canines are most dark and yellowish. The central incisors and lateral incisors showed the similar color patterns. 2. In the comparison between gender, it showed that in the 10's group male have more yellowish, the 20's female have lighter and more redness, the 30's indicated more redness in female and in the 40's the lightness is more in female. 3. With aging, there was no significant change in L^* and a^* coordinates but a shift was in b^* to yellowish in the 30's and 40's in central incisors. Lateral incisors and canines showed a lighter and more yellowish tooth color with an irregular change of color coordinate in a^*. 4. In all teeth the middle and cervical portion showed close correlation with over 0.7(0.05>p) but color (a^*, b^*) showed higher correlation than lightness(L^*). 5. It has been shown that through the regression test the cervical color could be calculated by the middle color value.

소아에서 나타난 비구개관낭의 치험례

모정희,정현구,조태식,김효석,박성규,이난영 조선대학교 구강생물학연구소 2002 口腔生物學硏究 Vol.26 No.2

The nasopalatine duct cyst is the most common non-odontogenic cyst in the oral area and is thought to be originated from the epithelial remnants of the nasopalatine duct. The nasopalatine duct cyst have been mentioned to be an overall incidence of 1.7-11.9% of all jaw cyst. More males than females are affected by that. It could occur all around the age, and especially in their 40th and 60th it happens the most and in childhood it is very rare. Proper treatment for nasopalatine duct cyst is enucleation. In the case of very large cysts, it is likely to be a risk of naso-oral or antral-oral fistulas or of devitalization of teeth, marsupialization is indicated. The purpose of case report is that a nasopalatine duct cyst in is very rare in childhood. A 9-year-old boy was referred to the chosun university pedodontics clinic that this child who has anterior palatal swelling is in routine check. The size of the cyst was so big that the marsupialization was committed and obturator was put. This patient is on the continuous observation. we treated the nasopalatine duct cyst with obturator.

보론 첨가강에서 연주 냉각속도가 고온연성에 미치는 영향 연구 (주편 코너 크랙 발생 방지 방안 확보 연구)

조경철 ( Kyung Chul Cho1 ),구양모 ( Yang Mo Koo ),박중길 ( Joong Kil Park ) 대한금속재료학회 2008 대한금속·재료학회지 Vol.46 No.6

사회과 경제교육과정의 개발에 관한 연구 : 스트랜드와 사회적 역할 및 시민성 차원을 중심으로 Focused on the Ideas of Strand, Social Role and Citizenship as Curriculum Strands

최병모,김경모,조병철 한국경제교육학회 2005 경제교육연구 Vol.12 No.1

유한요소법을 이용한 수직형 롤러 분쇄기용 테이블 라이너의 내구 해석에 관한 연구

최형모,이경영,조석수,이선봉 三陟大學校 産業科學技術硏究所 2002 産業科學技術硏究論文集 Vol.7 No.1

Vertical roller mill, which perform the grinding and parting blending of raw material, is the one of the important machine to produce ordinary portland cement. The table liner belonged to the vertical roller is mill the one of the main parts influencing its grinding efficiency. The life of table liner is estimatede to 4×107cycles in the design stage, but at the field, when its operating time reaches to 4×106 ~ 8×106 cycles, the fracture of table liner being to be found. The fracture of table liner commences from the outside edge of grinding path contacting with the grinding roller. Its maintenance normally take 30% of the total maintenance costs of the roller mill. Therefore, this study shows the clarification of the reasons occuring the fatal destruction of the table liner by fatigue fracture analysis utilizing fracture mechanics and by FEM using ANSYS 5.6.

중합가시광 파장대에 따른 심미성 수복재의 미세경도 변화

김현철,조경모,신동훈 대한치과보존학회 2001 Restorative Dentistry & Endodontics Vol.26 No.2

There are several factors affecting the effectiveness of polymerization of the esthetic restorative materials. Among those factors, the initiator, camphoroquinone has the unique characteristic, of which the light sensitivity is very dependent on the wavelengh of blue light. Camphoroquinone shows the most light absorption ability in the wavelengh range of 470nm. So most of clinically used light curing systems adopt this phenomenon as their polymerization mechanism. The most popular way of light curing system is standard 40-second curing. But the problem of standard curing technique shows the rapid increase of resin viscosity followed by the acceleration of polymerization and the limited resin flow, resulted in reduction of the physical property of restoration by retained stress. The object of this study was to verify the effects of narrow-banded wavelengh on the microhardness of the esthetic restorative materials, a composite resin and a composer, using filters which have peak wave-lengh of 430nm,450nm,470nm, respectively. The results were as follows : 1.All the experimental groups showed lower hardness value than the control group. 2.In DyractAP, the hardness value by wavelengh showed the same changing pattern on both upper and lower surfaces. 3.In DenFil, the hardness value by wavelengh showed different changing pattern on upper and lower surfaces. 4.The hardness ratio showed similar pattern to the hardness variation of lower surface, but there was no significant difference between measurement in 10 minutes and 3 days later, besides the increase of hardness value.

리본형태의 근관에서의 열연화 근관 충전법의 비교 : 근관 충전된 gutta-percha의 무게 WEIGHT OF FILLED GUTTA-PERCHA

김현희,조경모,김진우 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.3

The purpose of this study is to evaluate the two warm gutta-percha filling techniques by measuring the weight changes of resin blocks before and after canal filling in ribbon shaped canal. Simulated ribbon shaped root canals in 30 transparent resin blocks were instrumented to #40 using .06 taper Profile. 16 resin blocks were obturated with gutta-percha using cold lateral condensation. Warm lateral condensation using the Endotec Ⅱ was then accomplished on the same 15 blocks. Another 15 resin blocks were obturated using the System B. All canals were obturated without sealer. The resin blocks were weighed after canal preparation and after each subsequent obturation, and then weight changes of the resin blocks were calculated. The results were as follows. 1. Warm lateral condensation using Endotec Ⅱ and continuous wave of condensation using System B produced a denser obturation of gutta-percha compared with conventional cold lateral condensation (p<0.01). 2. There was no significant difference between warm lateral condensation and continuous wave condensation. In conclusion, the warm gutta-percha condensation techniques like warm lateral condensation and continuous wave condensation can be expected to bring favorable canal obturation results in ribbon shaped canals.

수종의 엔진구동형 Nickel-Titanium file을 이용한 근관형성 방법이 근관만곡도 유지능력에 미치는 영향

이철환,조경모,홍찬의 大韓齒科保存學會 2003 Restorative Dentistry & Endodontics Vol.28 No.1

There are increasing usage of Nickel-Titanium rotary files in modern clinical endodontic treatment because it is effective and fater than hand filing due to reduced step. This study was conducted to evaluate the effect of canal preparations using 3 different rotary Nickel-Titanium files that has different cross sectional shape and taper on the maintenance of canal curvature. Simulated resin block were instrumented with Profile(Dentsply, USA), GT rotary files(Dentsply, USA), Hero 642(Micro-Mega, France), and Pro-Taper(Dentsply, USA). The image of Pre-instrumentation and Post-instrumentation were acquired using digital camera and overspreaded in the computer. Then the total differences of canal diameter, deviation at the outer portion of curvature, deviation at the inner portion of curvature, movement of center of the canal and the centering ratio at the pre-determined level from the apex were measured. Results were statistically analyzed by means of ANOVA, followed by Scheffe test at a significance level of 0.05. The results were as follows; 1. Deviation at the outer portion of curvature, deviation at the inner portion of curvature were showed largest in Pro-Taper, so also did in the total differences of canal diameter(p<0.05). 2. All the groups showed movements of center. Profile combined with GT rotary files and Hero 642 has no difference but Pro-Taper showed the most deviation(p<0.05). 3. At the 1, 2, 3mm level from the apex movements of center directed toward the outer portion of curvature, but in 4, 5 mm level directed toward the inner portion of curvature(p<0.05). As a results of this study, it could be concluded that combined use of other Nickel-Titanium rotary files is strongly recommended when use Pro-Taper file because it could be remove too much canal structure and also made more deviation of canal curvature than others.

리본 형태의 근관에서 열연화주입법의 근관벽에 대한 적합도에 관한 연구 : ADAPTATION TO CANAL WALLS

황현숙,조경모,김진우 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.4

The aim of this study is to compare the adaptability of thermoplasticized injectable gutta-percha technique to the canal walls in ribbon-shaped canals. Thirty resin models simulated ribbon-shape canals were instrumented to #40 using. 06 taper Profile systems. Three groups of each 10 resin models were obturated by the lateral condensation technique(LC) and the two thermoplasticized injectable gutta-percha technique; Ultrafil Endoset+Obtura Ⅱ(EO) and Ultrafil Firmset(UF), respectively. After resin model were kept at room temperature for 4 days, they were resected horizontally with microtome at 1, 2, 3, 4 and 5mm levels from apex. At each levels, image of resected surface were taken using CCD camera under a stereomicroscope at ×40 magnification and stored. Ratio of the area of gutta-percha was obtained by calculating area of gutta-percha cone to the total area of canal using digitized image-analyzing program. The data were collected then analyzed statistically using One-way ANOVA. The results were as follows. 1. At 1mm levels, there was no statistically significant difference in the mean ratio gutta-percha among the groups. 2. At 2mm level, EO showed the highest mean ratio of gutta-percha (p<0.05) and there was no significant difference between LC and UF. 3. At 3, 4, 5mm levels, EO and UF and had significantly greater mean ratio of gutta-percha than LC(p<0.05) and there was no significant difference between EO and UF. In conclusion, the thermoplasticized injectable gutta-percha techniques demonstrated relatively favorable adaptability to canal walls than lateral condensation technique in ribbon-shaped canals except for 1mm level.