수학교육에서의 증명의 엄밀성에 관한 고찰

강윤수,정권수 順天大學校 師範大學 附屬 科學敎育硏究所 1996 科學과 敎育 Vol.4 No.-

Hanna stated that the stress on rigorous proofs does not improve the grasp of the mathematical facts. In this paper, we investigate the situation of Korean mathematical education in the perspective of Hanna's viewpoint. As a result, we make some suggestions through Fischbein's intuitive method of proofs, Leron's structural method of proofs and Hadar's method of generic - examples assisted proofs.

치근 천공 치료 재료의 생체친화성의 비교

강민경,배인호,고정태,황윤찬,황인남,오원만 대한치과보존학회 2009 Restorative Dentistry & Endodontics Vol.34 No.3

This study was carried out in order to determine in vitro biocompatibility of white mineral trioxide aggregate (MTA), and to compare it with that of the commonly used materials, i. e. calcium hydroxide liner(Dycal), glass ionomer cement (GIC), and Portland cement which has a similar composition of MTA. To assess the biocompatibility of each material, cytotoxicity was examined using MG-63 cells. The degree of cytotoxicity was evaluated by scanning electron microscopy (SEM) and a colorimetric method, based on reduction of the tetrazolium salt 2,3 bis {2methoxy 4nitro 5〔(sulfenylamino) carbonyl〕2H tetrazolium hydroxide} (XTT) assay. The results of SEM revealed the cells in contact with GIC, MTA, and Portland cement at 1 and 3 days were apparently healthy. In contrast, cells in the presence of Dycal appeared rounded and detached. In XTT assay, the cellular activities of the cells incubated with all the test materials except Dycal were similar, which corresponded with the SEM observation. The present study supports the view that MTA is a very biocompatible root perforation repair material. It also suggests that cellular response of Portland cement and GIC are very similar to that of MTA. 이번 연구는 치근 천공의 치료 재료인 white mineral trioxide aggregate (MTA)를 흔히 사용되는 calcium hydroxideliner(Dycal^(R), glass ionomer cement (GIC), 그리고 MTA와 유사한 성분을 가진 Portland cement와 세포독성 실험으로 생체 친화성을 평가하는 것이다. 세포독성의 정도는 MG-63 세포를 이용해 주사전자 현미경적 관찰과 수용성 tetrazolium salt를 이용한 흡광도를 측정 (XTT assay)하여 평가하였다. SEM 관찰에서, 1일과 3일째 모두에서 GIC와 MTA, Portland cement표면에서는 잘 부착된 세포를 보여주었다. 반면에, Dycal 표면의 세포들은 둥글고 부착되지 않은 양상을 보여주었다. XTT assay에서는 Dycal을 제외한 모든 재료에서 유사하게 높은 세포 활성도를 보여주었으며, 이는 SEM 관찰 소견과 일치하였다. 이번 연구는 MTA가 생체친화적인 재료라는 견해를 뒷받침한다. 또한 Portland cement와 GIC에서도 MTA와 유사한 세포반응을 보여주었다.

자외선 흡수제의 효과적인 합성 및 반응성에 관한 연구

康順姬,朴種倫,南貞姬 梨花女子大學校 韓國生活科學硏究院 1990 韓國生活科學硏究院 論叢 Vol.46 No.-

Derivatives of 2,4-dihydroxybenzophenone are widely used as UV light absorbers. Furthermore 4-hydroxybenzophenone derivatives have been reported as a new HNE inhibitor. In this study, these derivatives were prepared effciently by using DMAP as catalytic amounts(5mol%) on O-alkylation of 2,4-dihydroxybenzophenone with methyl sulfate, ethyl iodide, and ethyl bromide in the presence of potassium carbonate in acetone at 60℃. The products obtained were 2-hydroxy-4-methoxy-benzophenone, and 2,4-dimethoxybenzophenone, 2-hydroxy-4-ethoxy-benzophenone, and 2,4-diethoxybenzophenone. When DMAP was used as a catalyst, the reaction time had been shorthened enormously by comparing with that of the reaction without DMAP.

방광 크롬친화세포종과 동반된 배뇨후 벼락두통

하윤석,강성진,허소영,이지현,김민정,김종국,김광수 고신대학교 의과대학 2009 고신대학교 의과대학 학술지 Vol.24 No.1

Thunderclap headache is a hyperacute, severe headache that is so named because the pain strikes suddenly and severely, and is sometimes a sign of a medical emergency. We report a case of pheochromocytoma in the urinary bladder in a 48-year-old woman who presented with recurrent thunderclap headache after voiding and exercise. So we think thunderclap headache during or immediately after micturition may be an important diagnostic clue of bladder pheochromocytoma.

마이크로 엔드밀링에서 음향방출 신호를 이용한 상태감시

정연식,강익수,김전하,강명창,김정석,안중환 한국공작기계학회 2004 한국공작기계학회 추계학술대회논문집 Vol.2004 No.-

Ultraprecision machining and MEMS technology have been taken more and more important position in machining of microparts. Micro endmilling is one of the prominent technology that has wide spectrum of application field ranging from macro parts to micro products. Also, the method of micro-grooving using micro endmilling is used widely owing to many merit, but has problems of precision and quality of products due to tool wear and tool fracture. This investigation deals with state monitoring using acoustic emission(AE) signal in the micro-grooving. Characteristic evaluation of AE raw signal, AE hit and frequency analysis for state monitoring is also presented in the paper.

급성 림프구성 백혈병 환자에서 아스페르길루스 감염을 동반한 호중구감소성 소장결장염에 의한 작은창자 천공

강동백,임태수,박원철,윤기중,이정균 圓光大學校 醫科學硏究所 2008 圓光醫科學 Vol.23 No.2

저자들은 급성 림프구성 백혈병 치료 도중 아스페르길루스 감염을 동반한 호중구감소성 소장결장염에 의한 작은창자 천공을 경험하였다. 급성 림프구성 백혈병의 항암화학치료 중 발생 할 수 있는 호중구감소성 소장결장염은 다양한 위장관 증상을 보일 수 있으며, 이에 대한 발생 가능성을 고려하여 적극적인 조 기진단과 이에 대한 적극적 치료가 필요하며, 면역기능의 저하로 아스페르길루스 등의 진균 감염이 발생할 수 있으므로 호중구감소성 소장결장염의 치료에 증상의 호전이 없을 때 항진균제를 포함한 광범위한 치료가 고려되어야 한다. Though advancesin imumosuppressive therapy or chemotherapy which have lead to increased survival of leukemia and transplant patient, but the risk of infectious complication has been increasing. Neutropenic enterocolitis is a life threatening complication of chemotherapy for malignancies such as leukemia or lymphoma. Symptoms of neutropenic enterocolitis are nonspecific and it may rapidly lead to intestinal peforation. Aspergilus infection could involve the gastrointestinal tract as a result of neutropenia and mucosal injury after imumosuppressive therapy, chemoetherapy, or antibiotics use, but rarely reported a small bowel perforation combined aspergillus and neutropenic enterocolitis. We present a rare case of ileal perforation caused by neutropenic enterocolitis combined with aspergillus infection during chemotherapy for acute lymphocytic leukemia with a review of the literature.

노인 건강식 한방 삼계탕의 제조 및 품질 특성 : Manufacturing and Quality Characteristics of Herb

정대윤,강정화,은종방 全南大學校 農業科學技術硏究所 2011 農業科學技術硏究 Vol.46 No.-

The physiochemical characteristics and sensory properties of herb Samgyetang added with different dried medicinal herbs were investigated to find the best formulation for elderly healthful dietary. For the herb Samgyetang product, a fixed ratio of Achyranthis radix, Rehmanniae radix, Schizandra chinensis, Atractylodes lancea, Glycyrrhiza glaba L, and Zizyphus jujube were mixed with different concentrations of Paeonia lactiflora (PL) or Platycodon grandiflorum (PG), respectively for the development of new formulation. The pH of herb Samgyetang decreased as PL amount increased and the soluble solid content increased as PG amount increased. S6 showed the highest a* value and b* value, which had the highest addition level of PL. In contrast, S5 was the lowest a* value and b* value. In sensory evaluation, the highest score in flavor, taste and overall acceptability was found in the sample with the highest amounts of PG (S7). In conclusion, the following is suggested as the best formulation of herb Samgyetang : 10% PL, 40% PG, 5% Achyranthis Radix, 5% Rehmanniae Radix, 15% Schizandra chinensis, 10% Atractylodes lancea, 5% Glycyrrhiza glaba L, and 10% Zizyphus jujube.

미스트 분무 및 스프링클러 관수가 단동 플라스틱 하우스에 미치는 냉각효과

강정윤,임홍성,최동호,허종철 濟州大學校 産業技術硏究所 2000 산업기술연구소논문집 Vol.11 No.1

As crops recently can be cultivated all the year in greenhouses. we need to improve the environment in which crops are able to grow in the summer. Therefore. in this study. we quantitatively got the cooling effects of 4 single span plastic greenhouses in the following ways: by spraying mist or sprinkler. or by opening the side window. and with those variables. we simultaneously did experiments at 4 greenhouses under equivalent conditions to reduce the temperature of the greenhouses in the summer. The results of the experiments are as following : 1) The temperatures of the greenhouses were effectively reduced by both spraying mist and sprinkler. 2) When the mist is intermittently sprayed. the indoor temperature has decreased by 4 degrees centigrade. meanwhile. in the greenhouse to make experiments using sprinkler. the temperature of that has been reduced by 2 degrees centigrade. Therefore. we can see the cooling effects of smaller mist in size as more effective than those of sprinkler. 3) When the greenhouse is naturally ventilated by opening the side window. we have to apply another cooling system because the indoor temperature is higher than the outdoor one.

TRISS Method를 이용한 외상 환자 관리의 평가

윤영국,서강석,이정헌,김종근,감신 대한응급의학회 1996 대한응급의학회지 Vol.7 No.2

Trauma is well known as a major cause of death and disability in Korea, but we do not have a optimal method to evaluate the trauma patients effectively. The purpose of this study was to predict the prognosis and mortality of the trauma patients and to evaluate the quality of trauma care by TRISS method. A retrospective study of 100 cases of trauma victims who visited to emergency room and was admitted to surgical intensive care unit of Kyungpook University Hospital from January 1994 to December 1995 by TRISS method was made. In this study, we have found out following results. 1. Sex ratio of male to female was 4:1 and the mean age was 44 years. 2. Analysis of injury mechanism showed high incidences of traffic accident(71%), fall down(14%), cultivator(5%), penetrating trauma(3%) in order of frequency. 3. A comparison between survivors and deaths showed difference in TS(14.81±1.31 vs.13.64±1.43), RTS(7.26±0.82 vs. 6.78±10.24 vs. 37.45±11.05), TRISS Ps-1 TS and ISS(0.93±0.11 vs. 0.79±0,15), and TRISS Ps-2 by RTS and ISS(0.89±0.15 vs. 0.73±0.19). 4. By TRISS method, unpredicted outcomes occurred in 11 of 100 with 10 unpredicted deaths and 1 unpredicted survivor by TRISS-1 and unpredicted outcomes occurred in 14 of 100 with 9 unpredicted deaths and 5 unpredicted survivors by TRISS-2. 5. The most common cause of death was chest trauma(36.4%). 6. The Z statics, quantitating the difference in the actual number of deaths and the predicted number of death, using TRISS-1 method was 0.84 and using TRISS-2 method was -0.57. The authors conclude that the real dead patients exceeded the predicted outcome in TRISS-1 and the real dead patients were less than the predicted outcome in TRISS-2, and our patient management as well as application of this method should be analyzed for accurate outcome. In conclusion, TRISS method offers a good approach for predicting the prognosis and mortality of the trauma patient and evaluating trauma care.

진행성 비소세포폐암의 이차항암화학요법으로서 Docetaxel 단독요법의 성적

강현모,이정은,장필순,이연선,권선중,안진영,정성수,김주옥,김선영 충남대학교 암연구소 2006 암연구소 업적집 Vol.5 No.-

Background : The survival benefit associated with first-line chemotherapy in lung cancer has led to the need for second -line chemotherapy, for which Docetaxel (Taxotere^(?)) has proven efficacy in both settings. This study evaluated the safety and efficacy of docetaxel in patients with non-small cell lung cancer who had failed first-line platinum-based chemotherapy. Methods : Thirty one patients with non-small-cell lung cancer, who had failed first line platinum-based chemotherapy, between March 1999 and August 2003, were enrolled in this study. Patients received intravenous docetaxel, either 75 mg/㎡ or 100 mg/㎡, with routine premedication every three weeks. Results : Fourteen patients (45.2%) had a partial response. The median survival and progression- free survival times were 12.5 months (95% CI 7.3-17.6) and 3.0 months (95% CI 1.6-4.5), respectively. This study showed 2 factors gave different survival benefits; the age (< 60 years: 20.1 months vs. > 60 years: 6.6 months, p=0.0105) and the histological type (adenocarcinoma: 25.6 months vs. others: 7.9 months, p=0.0055). The predominant toxicity was neutropenia, which occurred as WHO grade 3 or 4 in 38.7 % of patients. One treatment related death was also reported. Non-hematological toxicity was minor and easily controlled. There were no significant statistical differences in the survival benefit and toxicity between the two doses. Conclusion : Docetaxel, as second-line monotherapy, was well tolerated and effective in patients with non-small-cell lung cancer who failed first line platinum -based chemotherapy. (Tuberc Respir DiS 2005: 58: 465-472)