• Journal of the Mineralogical Society of Korea
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• v.14 no.1
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• pp.73-84
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• 2001

티타늄과 산소의 함량이 서로 다른 4가지의 합성 페롭스카이트형(perovskite-type) 광물(($K_2$$La_2$$Ti_{n}$/$O_{2n+4}$, n=3, 4, 5, 6; 14/mcm, 14/mmm, I42 m)을 대상으로 리트벨트(Rietveld)구조분석법을 실시하여 결정구조를 밝히고 티타늄함량에 따른 층상형 구조를 연구하였다. 4가지 합성시료에 대하여 구조분석을 실시한결과 대표적인 페롭스카이트형 광물인 토소나이트(taustonite, $La_{1-x}$ //$K_{x}$ /$TiO_3$, x<0.4)가 주성분으로 나타났으며 토스나이트내에 12개의 산소를 배위하는 A자리 양이온은 자리점유율에 의해 $La^{3+}$ 와 $K^{+}$ /의 치환관계를 보여준다 공간군은 14/mcm, 단위포는 a=5.505(1)~5.510(1)$\AA$, c=7.793(1)~7.796(1)$\AA$ V=236.25~236.66 $\AA^3$ 범위의 값을 갖는다. 구조의 정밀도를 나타내는 R지수를 살펴보면 $R_{B}$ 값은 5.31~9.10 S(GofF)값은 0.86~1.24로 각각 계산되었다. 12배위를 하는 A자리 양이온인 란탄과 산소의 평균거리는 2.755$\AA$이고 6배위를 하는 B자리 양이온인 티타늄과 산소의 평균거리는 1.948 $\AA$의 결과를 얻었다. 합성된페롭스카이트형 광물의 층상구조가 알려져 있지 않아 시뮬레이션을 통해 구조모델을 결정하였으며 그결과 n=3인 R-38시료에서만 두 종류의 층상 페롭스카이트($La_2$$K_2$$Ti_3$$O_{10}$ ) 구조 (A-type: 14/mmm, a=3.8178 $\AA$, c=29.9189 $\AA$, V=436.04 $\AA^3$, B-type: 142 m, a =3.8376 $\AA$, c=28.023 $\AA$, V=412.6 $\AA^3$)가 존재함을 확인하였으나 다른 시료에서는 토소나이트, 금홍석 외에 새로운 합성광물로 제파이트의 존재를 확인하였다.

• School Mathematics
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• v.11 no.1
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• pp.55-70
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• 2009

The purpose of this study is to implement Lakatos method in the teaching and learning of geometry for middle school students. In his landmark book , Lakatos suggested the following instructional approach: an initial conjecture was produced, attempts were made to prove the conjecture, the proofs were repeatedly refuted by counterexamples, and finally more improved conjectures and refined proofs were suggested. In the study, students were selected from the high achieving students who participated in the special mathematics and science program offered by the city council of Seoul. The students were given a contradictory geometric proposition, and expected to find the cause of the fallacy. The students successfully identified the fallacy following the Lakatos method. In this process they also set up a primitive conjecture and this conjecture was justified by the proof and refutation method. Some implications were drawn from the result of the study.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.79-82
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• 2010

The pomegranate (Punica granatum), especially its fruit, possesses a vast ethnomedical history and represents a phytochemical reservoir of heuristic medical value. The tree and fruit can be divided into several anatomical compartments, and the fruit juice, peel and oil are known to be weakly estrogenic and heuristically of interest for treatment of menopausal symptoms and sequellae. In this study, analysis of estrogen in pomegranate extract was carried out with LC/MS/MS. Three batches of pomegranate extract samples were used to analysis the target compounds (estrogen). The contents of estrogen derivatives in the samples were 38.6 ppb of estriol, 83.5 ppb of estrone, and 10.9 ppb of estradiol. This result suggests that the pomegranate extract can used for treatment of menopause symptoms in the woman.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.102-109
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• 1997

The structures of novel branched oligosaccharides synthesized by the acceptor reaction with dextransucrase from Leuconostoc mesenteriodes M-12 were proposed in accordance with the results obtained from enzymatic hydrolyses and a partial acid hydrolysis. The structure of branched oligosaccharide B4 was shown to be 62-O-$\alpha$-D-kojibiosylmaltose. Branched oligosaccharide B5 was shown to be 63-O-$\alpha$-D-kojibiosylpanose. By reacting the acceptor reaction products with endodextranase a novel branched oligosaccharide (D4) could be produced. D4 was derived from the result of endodextranase hydrolysis of oligosaccarides synthesized by the second acceptor reaction with dextransucrase and was resistant to endodextranase and glucoamylase. The proposed structure of D4 was 62-O-$\alpha$-D-kojibiosylisomaltose. Formation pattern of the acceptor reaction products smaller than d.p. 6 with linear or branched linkage was also shown.

• Archives of design research
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• v.11 no.1
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• pp.259-268
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• 1998

Ideals of beauty has expressed variously through the centuries and in different cultures. Each traditional 'togu' has it's own morphology (in the meaning of nonverval linguistic) as using various type of language in each cultural erea. Korean aesthetics on 'dogu'philosophy introduces a whole new set of basic concepts outside western aesthetic framework of beauty Most distinctive is the insistence on overcoming dichotomies, especially between cognition and emotion, (momism)body and mind, self and other, and individual and group. Several topics are particularly illuminating within aesthetics: furniture, calligraphy, traditional garments pose interesting challenging to the art/nature, inside/outside, ethics/desire dichotomies so crucial to moral and cultural context. aesthetics are equally deserving of philosophical scrutiny: the ways in which philosophy of 'dogu'and aesthetics are integrated with daily life, the emphasis on process or understanding context rather than product itself or product 'form'. Dogu did not separate daily life and aesthetics from understanding social context. Language of 'togu' also has own vocabulary and grammar. But we often cannot gain our persnol experience truthful beauty of togu until understand context of understanding. it would be immpossible to explain ,or to analize different way of thinkings and behaivor precisly without understanding same codes of language.

• Tuberculosis and Respiratory Diseases
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• v.51 no.5
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• pp.482-487
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• 2001

A pancreatic pseudocyst with a mediastinal extension is a rare clinical entity. Intrathoracic symptoms such as dysphagia or dyspnea due to compression or associated pleural effusions are quite common. The pseudocysts transverse the diaphragm via the esophageal hiatus or aortic hiatus or by eroding directly through the diaphragm. Here, we report a case of a pancreatic pseudocyst with a mediastinal extension presenting as dysphagia and dyspnea. The diagnosis was confirmed by computerized axial tomography of the chest and abdomen. Usually, the proper management of a large pseudocyst includes percutaneous or surgical internal drainage, but in this case the mediastinal components disappeared with conservative medical treatment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.3
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• pp.195-202
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• 1976

The present investigation was performed to find the lipid composition of the total lipids, the fatty acid components of the neutral lipids and the phospholipids, and the composition of sterols, from Spisula sachalinensis. The results obtained are as follows ; 1) The main components of the total lipids are phospholipids$(43.1\%)$, triglyceride$(36.2\%) $, and sterol $(10.3\%)$. 2) The phospholipids are mainly composed of phosphatidyl choline, phosphatidyl ethanols, mine, phosphatidal ethanolamine and phosphatidyl serine. 3) The main fatty acids of the neutral lipids, the ethanolamine phospholipids and choline phospholpids, are C20:5, C16:1, C16:0, C20:5, C18:0, C22:6 and C16:0, C20:5, C22:6, respectively. Oleic acid content of all fractions is very small compared with one of gastropoda lipids and fish oil. 4) Most of plasmalogen are present in the ethanolamine phospholipids and only trace of plasmalogen in the choline phospholipids. 5) Sterols to be found are 22-trans-norcholesta-5, 22-diene-$3\beta$-ol, 22-dehydrocholesterol, cholesterol, brassicasterol, 24-methylenecho-lesterol and $\beta-sitosterol$.

• Journal of the Korean Chemical Society
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• v.32 no.4
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• pp.377-384
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• 1988

Carotenoprotein from Salmo Salar eggs was purified and characterized by CM-cellulose, 50% $(NH_4)_2SO_4$, DEAE-cellulose and sephadex G-75 column. The chromoprotein had a spectrum with ${\lambda}_{max}$ 409, 540 and 580nm in p-buffer (pH 7.0) at initial step. Molecular weights by sephadex G-200 gel filtration were 50, 200 and 26,000 daltons. SDS-PAGE analysis showed a structure with four identical subunits (12,500 daltons). Its sample retained a small amount of carbohydrates and lipids. Amino acids were analyzed, and mannose, galactose and glucosamine also were identified. Carotenoid extacted with acetone was found to be astaxanthin ester by partition test, epoxy test, iodine test, allylic test, reduction, acetylation, uv/vis, ir and nmr datas. Stearate (47.9%) and palmitate (21.4%) were predominant fatty acids in the astaxanthin ester.

• Journal of Environmental Health Sciences
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• v.39 no.1
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• pp.32-42
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• 2013

Objectives: Cryptosporidium, a protozoan parasite, has been recognized as a frequent cause of waterborne disease due to its extremely strong resistance against chlorine disinfection. Although there has as yet been no report of a Cryptosporidium outbreak through drinking water in Korea, it is important to estimate the health risk of Cryptosporidium in water supply systems because of the various infection cases in human and domestic animals and frequent detection reports on their oocysts in water environments. Methods: This study evaluated the annual infection risk of Cryptosporidium in tap water using the quantitative microbial risk assessment technique. Exposure assessment was performed upon the results of a national survey on Cryptosporidium on the water sources of 97 large-scale water purification plants in Korea, water treatment efficacy, and daily unboiled tap water consumption. The estimates of the US Environmental Protection Agency on the mean likelihood of infection from ingesting one oocyst were applied for effect assessment. Results: Using probabilistic methods, mean annual infection risk of Cryptosporidiosis by the intake of tap water was estimated to fall within the range of $2.3{\times}10^{-4}$ to $1.0{\times}10^{-3}$ (median $5.7{\times}10^{-4}$). The risk in using river sources was predicted to be four times higher than with lake sources. With 0.5-log higher removal efficacy, the risk was estimated to be $1.8{\times}10^{-4}$, and could then be lowered by one-third. Conclusions: These estimations can be compared with acceptable risk and then used to determine the adequacy and priority of various drinking water quality strategies such as the establishment of new treatment technology.

• Education of Primary School Mathematics
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• v.16 no.1
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• pp.21-33
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• 2013

In this study, We analyzed the mathematical thinking of sixth grade students showed mathematics lessons through the application of Lakatos' methodology and search for the role of their teachers in this lessons. We supposed to find the solution to the way of teaching-learning regarding the Lakatos' methodology for the elementary school level. According to the stages of presenting a problem situation, suggesting an initial conjecture, examining the conjecture, and improving the conjecture, we had lessons 8 times that are applied to Lakato's methodology. We gathered and analyzed data from lessons and interviews recording videotapes, documents for this study. The participants showed a lot of mathematical thinking. They understood the problem situation with the skill of fundamental thinking and suggested the initial conjecture by the skill of developmental thinking and they found a counter-example to be able to rebut the initial conjecture by critical thinking. Correcting the conjecture not to have counter-example, they drew developmental thinking and made their thinking generalize.