• Journal of the Korean Ceramic Society
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• v.46 no.2
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• pp.211-218
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• 2009

For the Y5V characteristic MLCC which is very prone to crack, it is important to to find out the basic cause of the crack. After finding out the crack origin, the materials and processes should be developed to remove the crack. The microstructures of the cracks were investigated using the fractographic method for the various types of cracks such as an exterior crack, a cyclic thermal shock crack, and an piezo-electric crack. It was found out that the crack origin was the pore at the end of the Ni inner electrode after bake-out. Even though the three dimensional crack shapes were different, the crack origins were seemed to be similar. The exterior crack could grow from the origin with the aids of residual and applied stress. FEM (finite element method) analysis was used to calculate the stress distribution of residual and applied stress. And the concept of fracture mechanics was applied for the explanation of the crack initiation and propagation from the stresses concentration.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.36.1-36.1
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• 2014

The correlation between mass of Type Ia Supernova (SN Ia) host galaxies and Hubble residual is now well-established. The origin of this relation, however, is yet to be understood. We have used low-resolution spectra of early-type hosts from YONSEI (YOnsei Nearby Supernovae Evolution Investigation) project to measure central velocity dispersion and Lick/IDS absorption indices. By using the Evolutionary Population Synthesis (EPS) models, luminosity-weighted mean age and metallicity of host galaxies were determined from $H{\beta}$ and absorption lines. Here we will discuss the correlation between the velocity dispersion, which indicates the mass of galaxies, and mean age of stellar population in our sample of early-type host galaxies.

• Journal of the Korean Institute of Oriental Medical Informatics
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• v.20 no.1
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• pp.1-8
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• 2014

Objectives: This study aimed to find out the origin, efficiency in sasang constitutional medicine and dosage of Mu tong. Methods: Investigation and analysis was been done through 15 literatures like the pharmacopoeia of the five countries in east Asia, the literatures about sasang constitutional medicine and so on. Results and conclusion: The species of Mu tong in Korea is identical with the Mu tong in China, but different from Chuan mu tong and Guan mu tong in China. Mu tong is a kind of medicine using by kidney can be use at most 12 qian (about 45g) a day when treating heat closing in small intestine, edema, headache, dysentery and difficult urination on Soyangin(SY).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.4
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• pp.539-543
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• 1998

The relationship of growth-in defects such as crystal originated particles (COP), flow pattern defects(FPD), laser scattering tomography defects (LSTD) was investigated in Cz-Si single crystals which had different pulling speed during crystal growing. It is concluded that the density and radial distribution of grown-in defects is strongly dependent on the pulling speed. And as the generation areas of these grown-in defects in a wafer are identical in radial position, they can be generated from same origin during crystal growing.

• Korean Journal of Veterinary Service
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• v.20 no.2
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• pp.183-189
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• 1997

This article reports a spontaneous thoracic teratoma in a laying hen (Deklb brown warren). In this case, a 40 days old hen was submitted for necropsy as part of an investigation into a flock problem suspected Marek's disease to Chonbuk Veterinary Service Laboratory in 1983. On the gross finding, mass was In the cranial subpulmonary cavity and attached to the vertebral column. It contained fully developed contour feathers. Histologically, feathers were arised from feather follicles complete with arrector plumi muscle, nerve, vessel and mucous gland composed with simple tall columnar epithelium. The outer surface of mass was lined by keratinized or nonkeratinized stratified squamous epithelium. It converted to pseudostratified ciliated columnar epithelium in some area. There were lymphocyte infiltration around gland tissue and eosinophilic intranuclear inclusion bodies in nonkeratinized epithelium. This thoracic teratoma was composed of ectodermal origin, squamous epithelium and nerve, and endodermal origin, mucous gland. This case in laying hen has never been reported in the literature in the world.

• YAKHAK HOEJI
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• v.42 no.6
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• pp.627-633
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• 1998

Impurity profiling analysis of methamphetamine seized in Korea was investigated for the evidential and intelligent purpose. Samples were extracted with ethylacetate which contai ns internal standard of dioctylsebacate under basic condition and extracts were analyzed by GC-FID. Ephedrine, chloroephedrine & 1,2-dimethyl-3-phenylaziridine were identified impurities in illicit methamphetamine by GC-MS. These impurities revealed that most of abused methamphetamine in Korea were synthesized from ephedrine as a starting material. For the classification of samples. firstly, 24 impurity peaks were selected after inspection of every peak in 50 samples as the specific markers of impurities. Secondly, corresponding peak retention time and area ratio to the internal standard were calculated and database was created with values of 24 peaks by in-house program. Finally, cluster analysis was attempted with the resultant profiles using the STAR plot, which was based on the Euclidian distance for evaluating similarity among samples. A total of 76 samples were divided into 8 different groups within 90% statistical similarity and inter-batch samples showed similar impurity patterns by this procedure. In conclusion, the analysis of impurities is a suitable index for estimation the common or different origin of methamphetamine sample.

• Fire Science and Engineering
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• v.33 no.2
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• pp.98-106
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• 2019

As lithium batteries have been used for car navigation systems and as the second battery for black boxes, lithium battery-related car fires have often occurred. In the case a lithium battery is the fire origin, a fire investigation technique has not been established to determine if a battery ignites or whether the lithium battery is damaged by fire. This study introduced car fire cases related to lithium batteries, analyzed the causes of a fire of a lithium battery, and proposed fire investigation techniques to objectively determine if a lithium battery ignites or whether a lithium battery is damaged by fire after external ignition.

• Ocean Science Journal
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• v.40 no.1
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• pp.45-54
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• 2005

The history of investigation of the family Velutinidae from 1776 to the present day is briefly described in the last part of this review; the contemporary system of the family, consisting of 39 species and subspecies, belonging to 17 genera and subgenera, and three subfamilies, is presented here. A biogeographic analysis of the fauna has been made, the history of origin and development of the family, vertical distribution and relation to substrates have been described in this work.

• Journal of Pharmacopuncture
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• v.12 no.2
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• pp.67-75
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• 2009

Objectives : This study was performed to developing orally administered analgesics and locally injected pharmacopuncture analgesics like opioids. Methods : Literary investigation on the origin of poppy (Papaver somniferum L) and other narcotics was conducted to examine the potential of developing orally administered analgesics and locally injected pharmacopuncture analgesics. Opium is a gum-like mass derived from air-dried white fluid of immature fruit of the poppy. Opium contains approximately 20 types of alkaloids including morphine, codeine, thebaine, papaverine and others. Natural opioids and synthetic alkaloid derivatives are the constituents of opioid analgesics and their effects and side-effects depend on the peculiarities of receptors. An extreme caution is required in the selection of proper dosage, proper analgesic types, and indications for successful pain management. Results and Discussion : With the enactment of "Narcotic control protocol", herbs such as cannibis and poppy are no longer available for use by Korean medicine doctors, and these doctors are faced with difficulty in managing severe pain in the clinical environment. A systematic consideration is inevitable for overcoming the limitation on these analgesics.

• The Korean Journal of Food And Nutrition
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• v.29 no.3
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• pp.357-362
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• 2016

The objective of this study is to investigate the perception and satisfaction of elementary and middle school students on free school food service. We surveyed education related to school food service, concerns about food ingredients, perceptions of free school food service and satisfaction for the quality of the school food service. The investigation is classified into two groups, schools that operate as a food service center or those that do not. Those who are provided food ingredients by school food service centers are educated about the agricultural products' country-of-origin and their environment-friendly food service. The more individuals are educated of the foods' county-of-origin and environment-friendly food service the more they will have a higher concern of the food materials and subsequently a higher satisfaction for the quality of school food service. School food service centers managed directly by the local government would probably receive higher satisfaction than those consigned to a private sector. The results of this study will be meaningful to establish policies on school food service and school food service centers.