• Journal of the korean academy of Pediatric Dentistry
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• v.10 no.1
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• pp.67-76
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• 1983

The state of pulp and dental hard tissue during the process of resorption and shedding of 104 non-carious primary teeth was assessed by histomorphologic study. The teeth were extracted from the Korean school children aged 5 to 15 and classified into preshedding, shedding, delayed shedding groups according to the age of the child at the time of extraction, The results were as follows: 1. The inflammatory cell infiltration in primary pulp tissues occurred in 61.5% of observed teeth and were increased in the order of preshedding, shedding and delayed shedding stages. 2. The odontoclasts were appeared in 43.3% of observed teeth and were increased in the order of preshedding, shedding and delayed shedding stages. 3. The polymorphonuclear leukocytes and odontoclasts couldn't be observed in the exfoliated primary pulp tissues before the process of resorption has involved the root surface about 1.8mm subjacent to the cemento-enamel junction. 4. The intact root surface was the longest and largest in the preshedding stage. 5. The resorption process of primary teeth roots occurred mainly in the stage of preshedding and shedding stages. 6. There was a tendency of repair of resorbing root surfaces in the delayed shedding stage.

• Journal of the Korea Computer Graphics Society
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• v.7 no.1
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• pp.37-49
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• 2001

We propose an optimization of mutual information for multiresolution image registration to represent useful information as integrated form obtaining from complementary information of multi modality images. The method applies mutual information as cost function to measure the statistical dependency or information redundancy between the image intensities of corresponding pixels in both images, which is assumed to be maximal if the images are geometrically aligned. As experimental results we validate visual inspection for accuracy, changning initial condition and addictive noise for robustness. Since our method uses the native image rather than prior feature extraction, few user interaction is required to perform the registration. In addition it leads to robust density estimation and convergence as applying non-parametric density estimation and stochastic multiresolution optimization.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.48-55
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• 2015

1-Deoxynojirimycin (DNJ) has been extensively investigated for its applications as an a-glucosidase inhibitor in postprandial hyperglycemia, and has been applied to nutraceuticals and medicines to prevent or delay the progression of type 2 diabetes. However, the amount of DNJ in mulberry leaves is low (approximately 0.1%), therefore, a more effective extraction method is needed. In this study, microbial DNJ production was developed as an alternative to chemical methods. We identified fermented sericultural products and bacteria that produce DNJ in large quantities using high performance liquid chromatography and thin layer chromatography. The inhibition of a-glucosidase activity was examined with respect to DNJ production or non-production. Crude DNJ from the isolated strains exhibited greater than 70% a-glucosidase activity. An investigation of the effect of mulberry leaf powder concentration (1~5%), using high DNJ producing bacteria, provided evidence for microbial mass production of DNJ.

• Analytical Science and Technology
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• v.15 no.1
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• pp.26-30
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• 2002

In order to determine the contents of ethyl carbamate in Korean traditional alcoholic beverages and general beverages, GC/MS-SIM method was used after extraction of beverages with dichloromethane. The contents of ethyl carbamate in Korean traditional alcoholic beverages, non-distilled alcohol, and whisky were detected in the range of $4.6-50.2{\mu}g/L$, $27.8-45.4{\mu}g/L$, and $24.8-55.1{\mu}g/L$, respectively. The recoveries were ranged from 83.3 to 104.8 %. The values of relative standard deviation were ranged from 1.8 to 14.8 % and the detection limit was $0.3{\mu}g/L$.

• Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.163-168
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• 2012

The non-utilized biomass of the aquacultured seaweed Undaria pinnatifida, particularly the rhizoid, is an alternative source of arachidonic acid (AA). Of the five aquacultured kelps that were tested, U. pinnatifida yielded the highest amount of AA, which was isolated from the rhizoids. Its identity (C20:4 n-6) was confirmed from gas chromatography-mass spectrometry spectral data. The optimal conditions for post-harvest storage or pretreatment of the rhizoids in Provasoli's enriched seawater for AA extraction were determined to be pH 7.8, 2% $CO_2$-enriched air, 20 ${\mu}mol\;m^{-2}\;s^{-1}$ light, and $10^{\circ}C$. Under these conditions, the AA content after 1 day of storage was enhanced by up to 127%. In the absence of light under ambient aeration, the AA content after 1 day of storage diminished to 90%. Rhizoids collected late in the season (April and May) contained the highest amounts of AA (approximately 2.5 mg/g tissue).

• Journal of Korea Multimedia Society
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• v.10 no.6
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• pp.754-759
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• 2007

Methodology of ontology building based on Web resources will not only reduce significantly the ontology construction period, but also enhance the quality of the ontology. Remarkable progress has been achieved in this regard, but they encounter similar difficulties, such as the Web data extraction and knowledge acquisition. This paper researches on the characteristics of ontology construction data, including dynamics, largeness, variation and openness and other features, and the fundamental issue of ontology construction - formalized representation method. Then, the key technologies used in and the difficulties with ontology construction are summarized. A software Model-OntoMaker (Ontology Maker) is designed. The model is innovative in two regards: (1) the improvement of generality: the meta learning machine will dynamically pick appropriate ontology learning methodologies for data of different domains, thus optimizing the results; (2) the merged processing of (semi-) structural and non-structural data. In addition, as known to all wetland researchers, information sharing is vital to wetland exploitation and protection, while wetland ontology construction is the basic task for information sharing. OntoMaker constructs the wetland ontologies, and the model in this work can also be referred to other environmental domains.

• Journal of KIISE:Software and Applications
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• v.27 no.4
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• pp.441-447
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• 2000

Automatic word spacing is needed to solve the automatic indexing problem of the non-spaced documents and the space-insertion problem of the character recognition system at the end of a line. We propose a word spacing algorithm that automatically finds out word spacing positions. It is based on the recognition of Eojeol components by using the sentence partition and bidirectional longest-match algorithm. The sentence partition utilizes an extraction of Eojeol-block where the Eojeol boundary is relatively clear, and a Korean morphological analyzer is applied bidirectionally to the recognition of Eojeol components. We tested the algorithm on two sentence groups of about 4,500 Eojeols. The space-level recall ratio was 97.3% and the Eojeol-level recall ratio was 93.2%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.2
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• pp.162-168
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• 2006

Recently, diagnosis techniques have been investigated to detect a Partial Discharge associated with a dielectric material defect in a high voltage electrical apparatus, However, the properties of detection technique of Partial Discharge aren't completely understood because the physical process of Partial Discharge. Therefore, this paper analyzes the process on surface discharge of polymer insulator using wavelet transform. Wavelet transform provides a direct quantitative measure of spectral content in the time~frequency domain. As it is important to develop a non-contact method for detecting the kaolin contamination degree, this research analyzes the electromagnetic waves emitted from Partial Discharge using wavelet transform. This result experimentally shows the process of Partial Discharge as a two-dimensional distribution in the time-frequency domain. Feature extraction parameter namely, maximum and average of wavelet coefficients values, wavelet coefficients value at the point of $95\%$ in a histogram and number of maximum wavelet coefficient have used electromagnetic wave signals as input signals in the preprocessing process of neural networks in order to identify kaolin contamination rates. As result, root sum square error was produced by the test with a learning of neural networks obtained 0.00828.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.1
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• pp.24-30
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• 2016

1-Deoxynojirimycin (DNJ) have been extensively investigated for their α-glucosidase inhibitor on postprandial hyperglycemia, and applied in nutraceuticals and medicine for preventing or delaying progression of type 2 diabetes. However, the amount of DNJ in mulberry leaves is low (about 0.1%), therefore, more effective extraction method is needed. This study was performed to develop microbial DNJ for biological methods of DNJ as an alternative to the chemical methods. In this study, we obtained evidence for Bacillus subtilis that produce DNJ in large quantities by high performance liquid chromatography. Inhibition of α-glucosidase activity was determined to DNJ production or non-production. Investigation of the effect of mulberry leaves powder concentration (1~5%), using the DNJ high-production bacteria, provided evidence for microbial mass production of DNJ. When the 4% mulberry leaf powder for 9 days was used, the α-glucosidase inhibitory activity was over the 85%. Also, the results presented in this study confirm DNJ yield's increasement in microbes using the various of nutrients and provide insight of ways to improve DNJ yields in microorganisms.

• Imaging Science in Dentistry
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• v.46 no.3
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• pp.223-227
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• 2016

A static, unilateral, and focal bone depression located lingually within the ascending ramus, identical to the Stafne's bone cavity of the angle of the mandible, is being reported. During development of the mandible, submandibular gland inclusion may lead to the formation of a lingual concavity, which could contain fatty tissue, blood vessels, or soft tissue. However, similar occurrences in the ascending ramus at the level of the parotid gland are extremely rare. Similar cases were previously reported in dry, excavated mandibles, and 3 cases were reported in living patients. A 52-year-old African American male patient was seen for pain in the mandibular teeth. Panoramic radiography showed an unusual concavity within the left ascending ramus. Cone-beam computed tomography confirmed this incidental finding. The patient was cleared for the extraction of non-restorable teeth and scheduled for annual follow-up.