Comparison of the Crystallization Behavior of Silica Between Mg and Al‑Phosphate Used in Tension Coatings of Grain‑Oriented Electrical Steel

Hyung‑Ki Park,Min‑Soo Han,Chang‑Hwan Chang,Jong‑Tae Park,박창수,Hyung‑Don Joo 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.3

The effect of the phosphate component on the thermal stability of tension coatings was investigated with a focus on thecrystallization behavior of amorphous silica in the tension coating. After stress-relief annealing, core loss of samples coatedwith a Mg-phosphate was improved, while that coated with an Al-phosphate was deteriorated. The domain wall spacing ofthe samples coated with Mg- and Al-phosphates was respectively increased and decreased after stress relief annealing. Thismeans that the stress relief annealing did not much diminish the tensile stress for Mg-phosphate coating but much diminishedthe tensile stress for Al-phosphate coating. Based on FTIR and XRD results, we found that the crystallization temperatureof silica with Al-phosphate was lower than that of silica with Mg-phosphate. The crystallization of silica was accompaniedby an abrupt volume change, which formed cracks in the tension coating and deteriorated the tensile stress.

악교정 수술에서 모의 조종된 3차원 전산화 단층촬영상의 응용

김형돈,이경상,유선국,박창서 大韓口腔顎顔面 放射線學會 1998 Imaging Science in Dentistry Vol.28 No.2

In orthodontics and orthognathic surgery, cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery, too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipments and because of its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram, pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms, and for validation of new method, in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery, computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of dry skull that position of mandible was displaced, range of displacement between computer-simulated three dimensional images and actual postoperative three dimensional images in co-ordinates values was from -1.8 mm to 1.8 mm and 94% in displacement of all co-ordinates values was from -1.0 mm to 1.0 mm and no significant difference between computer-simulated three dimensional images and actual postoperative three dimensional images was noticed(p>0.05). 2. In four cases of orthognathic surgery patients, range of displacement between computer-simulated three dimensional images and actual postoperative three dimensional images in coordinates values was from -6.7 mm to 7.7 mm and 90% in displacement of all co-ordinates values was from -4.0 to 4.0 mm and no significant difference between computer-simulated three dimensional images and actual postoperative three dimensional images was noticed(p>0.05). Conclusively, computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms. Therefore, potentiality that can construct postoperative three dimensional image without three dimensional computed tomography after surgery was presented.

부신적출이 조직 Li분포에 미치는 영향

김형근,성호경,이상돈 중앙대학교 의과대학 의과학연구소 1975 中央醫大誌 Vol.1 No.1

Effect of adrenalectomy on lithium distribution in various tissues of rats was studied. Rats were divided into three groups; namely, untreated, Li treated, and Li treated after adrenalectomy was done on 3rd dat prior to lithium treatment. Animals were killed following lithium treatment, and tissues including blood were taken immediately and digested and Li and Na concentrations were measured by atomic absorption spectroscopy. Effect of adrenalectomy on lithium distribution in various tissues was abserved, e. g. : brain skeletal muscle, bone, liver, renal cortex, cardiac muscle as well as plasma and erythrocyte. Correlations of Li concentrations were analyzed for each tissues. Results were smmarized as follows: 1. Adrenalectomy resulted an increase of lithium concentrations of various tissues in rats. 2. Erythrocyte to plasma ratio of lithium concentration was elevated in adrenalectomized rats, and it was considered that Li passed fairly well into cell under the adrenalectomy. 3. Adrenalectomy promoted the lithium retention in some tissues, especially bone, skeletal muscle and brain. 4. No correlation between tissues Li and Na was observed every tissues examined. 5. Lithium retention mechanism and pattern of distribution in some tissues of adrenalectomized rats were discussed.

굴 養殖場 水域의 基礎生産 硏究

李秉暾,姜亨求,姜龍柱 동의대학교 기초과학연구소 1992 基礎科學硏究論文集 Vol.2 No.1

The primary production of phytoplankton in oyster farming bays were seasonally measured by ^14C method in Hansan-Koje Bay and Kamagyang Bay for one year period. In Hansan-Koje Bay, mean daily primary production was 0.52gC/㎡/day(0.22∼1.02gC/㎡/day), and it was relatively high in summer and low in winter. Annual primary production was estimated to be 189gC/㎡/yr. Mean chlorophyll α content was 1.70mg/㎥, and it was relatively high in summer. In Kamagyang Bay, mean daily primary production was 0.91gC/㎡/day(0.11∼3.61gC/㎡/day), and it was maximum in summer and minimum in fall. Annual primary production was estimated to be 334gC/㎡/yr. Mean chlorophyll α concentration was 2.34mg/㎥, and it was maximum in summer and relatively high in winter. Considering the water area of the two osyter farming bays, annual carbon production by phytoplankton were 9,450 ton in Hansan-Koje Bay and 37,000 ton in Kamagyang Bay. In general pattern of primary production in these bays, high production occurs in summer with increasing trend since spring.

자성선숙어(protogynous fish)의 성전환

이영돈,고환봉,김형배,박인석,이정재 제주대학교 해양연구소 1993 해양자원연구소연구보고 Vol.17 No.-

Studies and reviews have been based on sex reversal diagnosis of histological change and body color change by sexual dimorphism on protogynous hermaphrodite fish, Labridae, Serranidae inhabited at the costal area of Chejudo. Korea Halichorens poecilopterus, Pleragoguw flagellifera and H. teruispinis were summer season, spawing species which mainly spawn in Jun and July, but Pseudolobrus japonicus was autumn season spawing species which mainly spawn in October and November, The standard length range of sex reversal were 13.0-15.0cm H. poecilopterus 9.5-15.0cm P. flagellifer, 11.5-16.0 cm P. japonicus and 10.0-13.0cm (total length) H. teraispinis respectively. Sex reversal mainly appeared before and after spawing season. H. Poecilogterus, H. terusispirus and P. japonicus were composed of monandry and diantry, but P.flagellifera was diandry. By sex reversal, the body colors of H. poecilopterus, P.flagellifera and P. japoricus change from pale red or yellow lines to brilliant green or dark yellow lines. The body colors of H. tenurisspirnis change slight, but containe lateral stripe pattern and blue spot in body center. In P. flagellifera, 1st, 2nd spine process of dosal fin were grown with body colour change. In sex reversal process, histological change of Labridae of inner gonad showed development of various interstitial cells and blood vessel by degeneration of oocyte. Thereafter, spermatogonia and spermatocyte begin to appear at the inner edge regions of the ovarian lamellae and then converted from ovary to functional testis. Epinephelus moara of 30.0~92.3cm in TL, E. Septemfasciatus of 23.4~38.7cm in TL were female with contained oocyte of perinucleolus stage. E akaara of 22.0~33.0cm in TL appeared individuals of ovotestis.

南原古詞 主題考

金炯敦 명지어문학회 1981 明知語文學 Vol.12-13 No.-

春香傳의 傳記的 構造 : 春香의 出生譚을 中心으로

金炯敦 명지어문학회 1983 明知語文學 Vol.15 No.-

연령에 따른 태권도 수련자와 비수련자에 대한 체격, 체구성 및 체력요인의 변화에 대한 비교

김형돈,장완성 慶熙大學校 社會體育硏究所 1998 體育科學論叢 Vol.- No.11

The purpose of this study was to investigate the differences of physique, body composition and physical fitness between the taekwondo trainees and non-trainees. The subjects consist of two experimental groups and two control groups. The experimental groups were trained for 1 to 2 year. According to the result of the study following conclusions were suggested: Group B revealed more significant difference in all the physical aspects than Group A. There were significant differences in the mean ration of flexibility within each comparison group(p<.05) With the mean ratio of physical efficiency index, Group B's index is 13.09% higher than Group A and has significant difference in statistics. No significant differences were found in the rest of the factors of physical fitness although Taekwondo trainee showed better scores in most of physical fitness test.

2-Bromopropane이 암컷 골든 햄스터의 생식기능에 미치는 영향

최돈찬,최형재,박창은 龍仁大學校 2000 용인대학교 논문집 Vol.18 No.-

Ovarian dysfunction induced by 2-bromopropane(2-BP) has been described in female factory workers and experimental animals. However, the underlying mechanism is still unclear. 2-BP is the possible causative chemical for reproductive and hematopoietic toxicity. To clarify the effect of 2-BP on the female reproductive function, repeated doses of 2-BP were administered to female golden hamsters for 24 days. Following 2 completed estrous cycles, animals received subcutaneously vehicle(corn oil), 80mg/kg, 400mg/kg, 2000mg/kg of 2-BP for 8 days. The females were then mated with males. The treatment continued for a gestation period(16 days). Dams treated with 2-BP showed a significant decrease in body weight. 2-BP decreased the fertility and tended to decrease the number of pups born and the rate of pregnancy, depending on the dose. The eccentric pyknotic cells, shrinkage of oocyte, and scattered cells were appealed in the middle and higher dose groups. The results indicate that reproductive toxicity induced by 2-BP was dose-dependent in that the higher doses exhibited more severe toxicity than the lower doses in our 24-day repeated dose experiments. Thus, 2-BP as a endocrine disrupter affects female reproductive activity to cause the destruction of primordial follicle and its oocyte in the ovary.

일반 측방 두부규격 방사선사진과 측방 두부규격 전산화 방사선사진에서의 계측점의 신뢰도에 대한 비교 연구

김형돈,박창서,김기덕 大韓口腔顎顔面 放射線學會 1997 Imaging Science in Dentistry Vol.27 No.1

The purpose of this study was to compare & to find out the variability of head film measurements(landmarks identification) between Fuji computed radiographic cephalometry and conventional cephalometry. 28 Korean adults were selected. Lateral cephalometric FCR film and conventional cephalometric film of each subject was taken. Four investigators identified 24 cephalometric landmarks on lateral cephalometric FCR film and conventional cephalometric film. The comparable measurements between lateral cephalometric FCR film and conventional cephalometric film were statistically analysed. The results were as follows: 1. In FCR film & conventional film, coefficient of variation (C.V.) of 24 landmarks was taken horizontally & vertically. There is no significant difference of rank order of landmarks in C.V. between two films. 2. In comparison of significant differences of landmarks variability between FCR film & conventional film, horizontal value of coefficient of variation showed significant differences in four landmarks among twenty-four landmarks, but vertical value of coefficient of variation showed significant differences in sixteen landmarks among twenty-four landmarks. FCR film showed significantly less variability than conventional film in 17 subjects among 20(4+16) subjects that showed significant difference.