이중구간중도절단된 생존자료의 생존함수 비교를 위한 검정: 한국인 암 예방연구 중 당뇨병에의 응용

지선하,남정모,김진흠,Jee, Sun-Ha,Nam, Chung-Mo,Kim, Jin-Heum 한국통계학회 2009 응용통계연구 Vol.22 No.3

이중구간중도절단된 자료의 생존함수를 비교하기 위한 두 검정법을 소개하고 한국인 암 예방연구 (Jee 등, 2005) 자료에 적용하여 당뇨병 잠복시간의 분포를 성별과 연령에 따라 비교하였다. Kim 등 (2006)의 검정법을 이중구간중도절단된 자료로 확장한 검정법은 위험집합의 크기에만 의존하는 가중값을 사용하기 때문에 대용량 자료의 분석에서 Sun (2006)의 검정법보다 계산 시간을 대폭 줄일 수 있으며, 이산형 생존자료뿐만 아니라 연속형 생존자료에도 적용가능한 장점이 있다. 당뇨병의 잠복시간이 성별에 따라 매우 유의하게 달랐으며 여자의 잠복시간이 남자보다 긴 것으로 나타났다. 4개 연령그룹 간 당뇨병의 잠복시간도 성별에 관계 없이 매우 유의하게 달랐으며 여자의 경우가 남자의 경우보다 그 차이가 훨씬 더 유의했다. 한편, 소표본 모의실험을 통해 제안한 검정법과 Sun (2006)의 검정법의 검정력을 비교하였으며 제안한 검정법의 검정력이 Sun (2006)의 검정법보다 더 좋은 것으로 나타났다. Two tests were introduced for comparing several survival functions with doubly interval-censored data and illustrated with data surveyed by Korean Cancer Prevention Study (Jee et al., 2005). The test which extended Kim et al. (2006)'s test to the doubly interval-censored data has an advantage over Sun (2006)'s test in terms of saving computation time because the proposed test only depends on the size of risk set, and also the proposed test is applicable to continuous failure time data as well as discrete failure time data unlike Sun's test. Comparing male with female groups on the incubation time of diabetes was highly different and the survival of female group was longer than that of male one. Regardless of gender, the difference in survival functions of four age groups was highly significant with p-value of less than 0.001. This trend was more remarkable for female group than for male one. Simulation results showed that the significance level of both tests was well controlled and the proposed test was better than Sun's test in terms of power.

Thermodynamic Calculations and Parameter Variations for Improving the Extraction Efficiency of Dy in Ternary Alloy System

Sun‑Woo Nam,Sang‑Min Park,Do‑Hyang Kim,Taek‑Soo Kim 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.3

The extraction behavior of dysprosium (Dy) in a rapidly solidified Dy–Fe–B alloy system consisting of Dy2Fe14Band Dy6Fe23phases was investigated using the liquid metal extraction (LME) process. Liquid magnesium (Mg) was selected as the solventmetal in LME because it forms intermetallic compounds with Dy but not with iron (Fe) and boron (B) in this process. Thediffusion behavior of Dy was estimated through thermodynamic calculations and subsequently confirmed by process parameterssuch as temperature and reaction time. As the temperature increases, the extraction rate increases and the maximumextraction efficiency is about 74% Dy for 1 h at 1000 °C. As the reaction time increases, we achieved the maximum extractionefficiency of 95% Dy after 24 h at 900 °C. The factor affecting Dy extraction ratio up to 6 h is Dy6Fe23phase, after which theextraction mainly occurs in Dy2Fe14Bphase. Furthermore, the diffusion behavior is described in detail with analysis basedon microstructural and compositional properties. The effects of process parameters on extraction rate are also discussed.

변색 실활치에 대한 carbamide peroxide gel의 표백효과

박선아,김선호,황윤찬,오병주,윤창,박영준,정선와,황인남,오원만 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.4

The bleaching of discolored nonvital teeth is conservative treatement that satisfy the cosmetic desire. The most common method for this treatement, walking bleaching, is using 30% hydrogen peroxide and sodium perborate. Many alternatives are suggested for preventing the external cervical root resorption that is the common complication of the nonvital teeth bleaching with 30% hydrogen peroxide. The same extent of oxidation reactions as that resulted by the bleaching with the application of 30% hydrogen peroxide and sodium perborate can also be acquired more safely by materials that contain 10% carbamide peroxide, used primarily for the bleaching of vital teeth. Therefore, this study was performed to evaluate the efficacy of 10% and 15% carbamide peroxide bleaching gel in nonvatal teeth bleaching. The internal bleaching of intentionally discolored teeth was performed in vitro with 10% carbamide peroxide (Group 1), 15% carbamide peroxide (Group 2), mixture of distilled water and sodium perborate (Group 3), and mixture of 30% hydrogen peroxide and sodium perborate (Group 4). The bleaching materials were refreshed following 3, 6, 9 and 12 days. To evaluate the bleaching effect, the color change of the crowns was measured at 1, 2, 3, 4, 7 and 15 days of bleaching using the colorimeter. The results were as follows : 1. L^* and ΔE^* values were increased with time in all bleaching agents(p<0.01). 2. There was no significant difference in L^* and ΔE^* value among bleaching agents. 3. Δ^* value higher than 3 was shown after 3 days of bleaching with 10% carbamide peroxide gel, 1 day with 15% carbamide peroxide gel, 4 days with mixture sodium perborate and distilled water and 4 days with mixture sodium perborate and 30% hydrogen peroxide, respectively. These results revealed that the use of 10% and 15% carbamide peroxide bleaching gel in non-vital teeth bleaching is as effective as mixture of distilled water and sodium perborate and mixture of 30% hydrogen peroxide and sodium perborate. Accordingly, carbamide peroxide could be used clinically to bleach discolored non-vital teeth.

保管條件에 따른 라면油脂의 酸敗에 關한 硏究

崔善男 군산대학교 1980 群山水産專門大學 硏究報告 Vol.14 No.3

Oxidative rancidity of the Ramyon lipids were studies under three experimental storage condition. Ramyon was (1) stored in the dark room (packed). (2) stored in the scattered light of room (packed). (3) exposed to the direct rays of the sun (unpacked). In the study, changes in Peroxide Value (POV) and Acid Value (AV) were determined with the lipids extracted from the Ramyon samples in intervals for four months;First 10 days in two days interval,4 months in 30 days intervals later. I.POV & AV increased slightly in the dark and scattered light during storage, while a sharp increase of those values were noticed with the samples of direst rays of the sun. II.Especially POV increased about three times for control within 10 days in unpacked and direct rays of the sun. III.Ramyon had stored in the dark and scattered light with package in 120 days showed POV less 60, was edible.

고체상포집-액체추출방법 및 GC-MS를 이용한 더덕의 향미성분 분석

이선녀,김남선,김건,이동선 서울여자대학교 자연과학연구소 2006 자연과학연구논문집 Vol.18 No.-

Codonopsis Radix (Codonopsis lancelata Bentham et Hooker) of the campanulaceae family is a perennial twining vine. Codonopsis Radixis is effective in protecting the stomachics and expectorant. It is an aromatic vine and has very strong sweet volatile compounds. Volatile flavor components of the codonopsis radix have been studied in this paper. The flavor compounds from the codonopsis radix were analyzed by head space solid phase trapping-solvent extraction and gas chromatography - ion trap mass spectrometry. trans-2-Hexenal, 4-methy-1-pentyn-3-ol, limonene, 3-methyl-1, 4-pentadiene, 4-methyl-2-penten-1-ol, trans-2-hexan-1-ol and 3-ethyl- cyclopentene were found as predominant components of codonopsis radix flavors.

웹 카메라를 이용한 시설 내 국화생산 광 환경 원격 모니터링

정선옥(Sun-Ok Chung),김용주(Yong-Joo Kim),이규호(Kyu-Ho Lee),성남석(Nam-Seok Sung),이철휘(Cheol-Hwi Lee),노현권(Hyun-Kwon Noh) 충남대학교 농업과학연구소 2015 농업과학연구 Vol.42 No.4

Increase of national family income improved demand of high-quality and year-round horticultural products including chrysanthemum. To meet these demand, farmers have introduced protected facilities, such as greenhouses, of which environmental conditions could be monitored and controlled. Environment management up to three weeks after transplanting is critical for chrysanthemum quality. Artificial lighting and light-blocking screen are especially important for long-day (day period > 13 hours) and short-day (night period > 13 hours) treatments. In this study, a web-camera was installed, and the image was obtained and transmitted to mobile phones to monitor the status of 3-wavelength(RGB) lighting environments. RGB pixel values were used to determine malfunctioning of the lighting lamps, and leaking out and incoming illumination status during short-day and long-day treatment periods. Normal lighting lamps provided RGB pixel values of 240~255. During long-day treatment period, G pixel values were useful to detect abnormal lighting conditions (e.g., leaking). During short-day treatment period, R pixel values were useful to determine incoming light (e.g., sun-light). Results of this study would provide useful information for remote monitoring of light conditions for protected chrysanthemum production under artificial lights.

백서에서 Depulpin®과 Formocresol에 대한 치수와 치근단 조직의 반응

문형인,김선호,황윤찬,오병주,황인남,김선헌,정선와,윤창,오원만 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.4

One fifth dilution of formocresol is usually for pulpotomy of the primary teeth and emergency pulpotomy of the permanent teeth. However, the use of formaldehyde has been subjected to criticism because it may be absorbed into the blood stream and become distributed systemically, it may also alter the pulp tissue rendering it immumologically active, and have carcinogenic potential. Recently Depulpin®(VoCo., Germany) gains popularity as a devitalizing agent during root canal therapy in spite of high concentration of 49% paraformaldehyde because it facilitate devitalization of pulp and make root canal therapy easier. But there have been not enough publications about the reaction of pulp and periapical tissue caused by Depulpin. This study was performed to evaluate the histological changes in pulp and periapical tissue of rats after pulpotomy using formocresol and Depulpin and to elucidate the toxic effects of these agents. Thirty six Sprague-Dawley rats were anesthetized by intraperitoneal injection of ketamine. Maxillary first molar teeth were used for pulpotomy with formocresol and Depulpin. Rats were sacrificed after 2 days, 4 days, 1 week, 2 weeks, 3 weeks and 4 weeks respectively. Specimens were histologically observed by light microscope changes in pulp and periapical tissue. The obtained results were as follows. 1. Formocresol group A zone of fixed tissue, in which odontoblasts could clearly be defined, was present directly underneath the pulpotomy dressing in almost all teeth of this group. This was followed by an area of necrotic tissue which resembled dried out fibrous tissue with no cellular detail except some pyknotic nuclei. In the specimens of after 2 days, 4 days, 1 week, 2 weeks in which vital tissue was present. it was separated from the fibrous area by a zone of inflammation. In the specimens of after 3 weeks and after 4 weeks, inflammatory infiltrate was in the periodontal ligament adjacent to the apical foramina of the teeth. 2. Depulpin® group The area of necrotic tissue which had no cells and fibers , was present adjacent to the dressing. This was followed by dried out fibrous tissue with no cellular details except some pyknotic nucleli. A short stump of vital pulp with odontoblasts was present at the end of the canal after 2 days. Inflammatory infiltrate was in the periodontal ligament after 4 days and after 1week. Severe root resorption and necrosis of periapical tissue opposite the root resorption site were defined after 2 weeks and after 3 weeks. Periapical lesion which consist of necrotic tissue surrounded by a fibrous connective wall. was found after 4 weeks. The results indicated that Depulpin can cause more adverse reaction to the dental pulp and periapical tissue than formocresol, and further studies are needed for its clinical use with safety.

적외선열화상장치를 이용한 Buchanan plugger 표면의 온도상승 분석

최성아,김선호,황윤찬,윤창,오병주,최보영,정우남,정선와,황인남,오원만 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.4

This study was performed to evaluate the temperature rise on various position of the Buchanan plugger, the peak temperature of plugger's type and the temperature change by its touching time of heat control spring. The heat carrier system 'System B' (Model 1005. Analytic Technologies, USA) and the Buchanan's pluggers of F, FM, M and ML sizes are used for this study. The temperature was set to 200℃ which Dr. Buchanan's "continuous wave of condensation" technique recommended on digital display and the power level on it was set to 10. In order to apply heat on the Buchanan's pluggers, the heat control spring was touched for 1, 2, 3, 4 and 5 seconds respectively. The temperature rise on the surface of the pluggers were measured at 0.5 mm intervals from tip to 20 mm length of shank using the infraed thermography (Radiation Thermometer-IR temper, NEC San-ei Instruments, Ltd, Japan) and TH31-702 Data capture software program (NEC San-ei Instruments, Ltd, Japan). Data were analyzed using a one way ANOVA followed by Duncan's multiple range test and linear regression test. The results as follows. 1. The position at which temperature peaked was approximately at 0.5 mm to 1.5 mm far from the tip of Buchanan's pluggers (p<0.001). The temperature was constantly decreased toward the shank from the tip of it(p<0.001). 2. When the pluggers were heated over 5 seconds, the peak temperature by time of measurement revealed from 253.3±10.5℃ to 192.1±3.3℃ in a touch for 1 sec, from 218.6±5.0℃ to 179.5±4.2℃ in a touch for 2 sec, from 197.5±3.0℃ to 167.6±3.7℃ in a touch for 3 sec, from 183.7±2.5℃ to 159.8±3.6℃ in a touch for 4 sec and from 164.9±2.0℃ to 158.4±1.8℃ in a touch for 5 sec. A touch for 1 sec showed the highest peak temperature, followed by, in descending order, 2 sec, 3 sec, 4 sec. A touch for 5 sec showed the lowest peak temperature (p<0.001). 3. A each type of pluggers showed different peak temperatures. The peak temperature was the highest in F type and followed by, in descending order, M type, ML type. FM type revealed the lowest peak temerature (p<0.001). The results of this study indicated that pluggers are designed to concentrate heat at around its tip, its actual temperature dose not correlate well with the temperature which Buchanan's "continuous wave of condensation" technique recommended, and finally a quick touch of heat control spring for 1 sec reveals the highest temperature rise.

ATO 복합사를 이용한 열차단 직물의 태양방사투과율 변화 연구

최주환,김대근,김선남,최동혁,이승걸,Choi, Joo Hwan,Kim, Dae Geun,Kim, Sun Nam,Choi, Dong Hyuk,Lee, Seung Geol 한국섬유공학회 2016 한국섬유공학회지 Vol.53 No.6

In this study, we manufactured ATO (antimony tin oxide) combined fibers to improve solar energy transmittance of sunscreen fabrics. The results indicate that the solar energy transmittance is improved with increasing sheath ratios and ATO content. We observed that the MS2-7W sample with 50:50 sheath/core ratio and 3 wt% of ATO content show the best performance. We also manufactured the sunscreen fabrics using the developed ATO combined fibers to check the performance of the thermal barrier. The results of the solar energy transmittance analysis show that an approximate 58% improvement was achieved for the thermal barrier over the commercial sunscreen fabric without any ATO content.

Thermocouple을 이용한 Buchanan Plugger 표면의 온도상승 분석

조진숙,황윤찬,김선호,황인남,최보영,정영진,정우남,오원만 전남대학교 치의학연구소 2003 구강과학 Vol.15 No.4

This study was performed to confirm the actual temperature rise on the surface of Buchanan plugger by evaluating the temperature rise on the surface of it, the peak temperature of pluggers of various size using thermocouple. The heat carrier system 'System B Heatsource' (Model 1005, Analytic Technologies, USA) and the Buchanan pluggers of F, FM, M and ML sizes are used for this study. The temperature was set to 200 which Dr. Buchanan's "Continuous wave of condensation" technique recommended on digital display and the power level on it was set to 10. The touch mode was used. Five thermocouples were placed in direct contact with the surface of each size of Buchanan's pluggers at 1 ㎜ increments from the tip to the 4 ㎜ length of shank. Each thermocouple was secured with cyanoacrylate adhesive and orthodontic resin block. The two wire leads of each thermocouple were connected to the appropriate channels of Data Logger. This was configured to simultaneously record input from the five thermocouples. The heat control spring was touched for 1, 2, 3, 4 and 5 seconds, and the temperature rise on the surface of the pluggers were measured at 1 sec intervals for more than 5 seconds with an accuracy of 0.01. Ten trials was determined for each plugger. The average of temperature rise and standard deviation was calculated for each size of plugger. The data were statistically analyzed by one-way ANOVA to determine their significance. The results as follows. 1. The position at which the temperature peaked was approximately at 1∼2㎜ far from the tip of Buchanan plugger (p<0.01). 2. The peak temperature was 215.25±2.28℃ in F plugger, 185.94±2.19℃ in FM plugger, 169.51±9.12℃ in M plugger, and 160.79±1.27℃ in ML plugger and the peak temperature was highest in F type and followed by, in descending order, FM type, M type. ML type showed the lowest peak temperature (p<0.01). This results suggest that the actual temperature on the surface of the pluggers does not correlate well with the temperature set on digital display. Heat concentrates around the tip. The larger plugger reveals lower temperature rise relatively.