• The Journal of Korean Academy of Prosthodontics
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• v.42 no.1
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• pp.1-10
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• 2004

Statement of problem : Tooth wear is physiological phenomenon. Ninety-seven percent of normal people have tooth wear and about 7% has pathologic teeth wear. If we know the amount of tooth surface loss caused by pathologic tooth wear, we may restore it ideally Purpose : Recently measurement of tooth wear by using 3D scan has been increasing. Therefore, we need to know how accurate 3D scan is. Past accuracy test on 3D scan was about linear change, but as we know that tooth wear is volume change. Thus, the purpose of this study is to know how accurate 3D scan is. Material and Methods : For accuracy test of 3D scanner volume values measured by 3D scanner and micro-balance were compared. For test I, preliminary, 3 ball samples and 3 circular cones were made with pattern resin. For test II, 10 teeth shape rubber samples were used. Results and Conclusion : 1. The result of the accuracy test on 3D scan with 3 ball samples and 3 circular cones made of pattern resin has no significant difference(p<0.05). 2. The result of the accuracy test on 3D scan with 10 samples of tooth shape rubber has no significant difference (p<0.05). As a result, we may concluded the analysis of quantifying tooth wear used by 3D scan is useful in the clinic.

• Electronics and Telecommunications Trends
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• v.34 no.4
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• pp.15-22
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• 2019

Recent technological advances in three-dimensional (3D) sensing devices and machine learning such as deep leaning has enabled data-driven 3D applications. Research on artificial intelligence has developed for the past few years and 3D deep learning has been introduced. This is the result of the availability of high-quality big data, increases in computing power, and development of new algorithms; before the introduction of 3D deep leaning, the main targets for deep learning were one-dimensional (1D) audio files and two-dimensional (2D) images. The research field of deep leaning has extended from discriminative models such as classification/segmentation/reconstruction models to generative models such as those including style transfer and generation of non-existing data. Unlike 2D learning, it is not easy to acquire 3D learning data. Although low-cost 3D data acquisition sensors have become increasingly popular owing to advances in 3D vision technology, the generation/acquisition of 3D data is still very difficult. Even if 3D data can be acquired, post-processing remains a significant problem. Moreover, it is not easy to directly apply existing network models such as convolution networks owing to the various ways in which 3D data is represented. In this paper, we summarize technological trends in AI-based 3D content generation.

• Journal of the Korean Institute of Navigation
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• v.23 no.2
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• pp.67-79
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• 1999

The purpose of this study is to provide basic date on the causes and factors related with the workload on board for Korea Seaman's Low Back Pain. The date had been acquisited through the questionaires of those and analysed in Korea Institute of Maritime and Fisheries Technology from February 10 to April 10 in 1999. The results of this study are as follows: 1. The incidence of Occupational low back pain for the recent 12 months has been recorded as 56.2% of the subject. 2. The highter Occupational satisfaction has the lower incidence of low back pain(p＜0.01). and the person who takes a rest(p＜0.05) and physical exercise regularly(p＜0.01) has lower experience of the incidence. 3. The incidence of low back pain by charateristics of vessel was turn out as 59.3% of the fishing vessel, 55.3% merchantmarine and 52.9% of the vessel of special purpose. The incidence of each department of a ship has recorded as 54.3% of Deck Dept. 59.2% of engine Dept but there was little relationship between those. And the longer period of work and on-board service has the hither incidence of the higher incdence(p＜0.01). 4. The fittness of the working table (p＜0.01) and chair(p＜0.01) has affeced the incidence of low back pain significantly 5. The higher incidence of low back pain has been experienced in case of working: in back posture, and lifting up or carrying a heavy load(p＜0.01) 6. The major cause of low back pain was turned out as excessive workload(26.5%) and stress (18.5%) ; the stress(24.1%) and excessive overwork(22.4%) for Deck dept. and excessive workload(32.3%) and bad position(21.7%) for Engine Dept(P＜0.01)

• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.736-740
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• 2002

An efficient and practical synthetic method of △1 -3-octalone, which is a versatile building block for thesyntheses of polycyclic compounds, has been developed. The dianion of ethyl acetoacetate reacts with cyclohexene-1-carboxaldehyde (3) to produce the aldol adduct 6, which then undergoes Mn(Ⅲ)-mediated radical cyclization followed by acetate elimination to give △1 -3-octalone 4. A detailed mechanistic insight of Mn(Ⅲ)-mediated cyclization of 6 has been disclosed.

• Proceedings of the Optical Society of Korea Conference
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• 1991.06a
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• pp.98-101
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• 1991

The As2S3 thin film has a characteristics of optical modulation in both amplitude and phase. Since the As2S3 thin film can be used as a real-time reconfigurable optical filter, the fSDF filter can be optically fabricated on it. According to the modulation characteristics of the As2S3, the optimal fSDF filter recorded on this thin plate has the form of continuous amplitude and binary phase. Computer simulation and optical experiments on the optical pattern classification show that the As2S3 is suitable for the optical fSDF filter.

• Journal of applied mathematics & informatics
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• v.30 no.3_4
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• pp.489-498
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• 2012

Most of the software reliability models are based on black box approach and these models consider the entire software system as a single unit. Present day software development process has changed a lot. In present scenario these models may not give better results. To overcome this problem an improved additive model has been proposed in this paper, to estimate the reliability of software with modular structure. Also the concept of imperfect debugging has been also considered. A maximum likelihood estimation technique has been used for estimating the model parameters. Comparison has been made with an existing model. ${\chi}^2$ goodness of fit has been used for model fitting. The proposed model has been validated using real data.

• The Research Journal of the Costume Culture
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• v.7 no.3
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• pp.93-107
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• 1999

Elderly population of Korea has been significantly increasing, therefore, social and economical influence of the elderly people has been increasing, too. Recently, research regarding elderly people is important because many elderly men take care of their appearance and clothing, and clothing plays an important role in everyday life. The purpose of this study is to investigate the clothing behavior of men aged 55 years and older who were residents of Seoul. The data were collected with a interview and self-administered questionnaire at various places. The importance of various factors on clothing behavior is different. 2. Age has a negative relationship with conformity, but a positive relationship with aesthetics and satisfaction of clothing. Allowance has a positive relationship with all clothing behaviors factors excepts conformity. 3. Life satisfaction has a positive relationship with education and allowance, also, life satisfaction of occupation group is higher than no occupation group is higher than no occupation group. 4. Appearance satisfaction has not a significant relationships with age, but, has a positive relationship with education. 5. There are positive relationships between not only life satisfaction and clothing behavior factors, but also appearance satisfaction and clothing behavior factors except conformity.

• Journal of Sasang Constitutional Medicine
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• v.10 no.1
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• pp.55-63
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• 1998

The symptoms that have same pathologic pattern written in the chapter of Soyangin's general pathology of the book 'Dongyi Soose Bowon' can give us a key to the Dr.Lee Je-Ma's point of view about the constitutional pathophysiology. As the result, Dr. Lee called the person who has yang-hyperactivity/yin-hypoactivity as So-Yang-In. And the Soyangin has two basic pathologic pathway ; excess of Yang-hyperactivity/excess of Yin-hypoactivity. Each pathologic pathway has variatons though, the pathologic pattern results in above two type. Excess Yin-hypoactivity has three variations of pathologic pattern. 1. smaller excess of Yin-hypoactivity with the normal range of Yang-hyperactivity 2. larger excess Yin-hypoactivity with the excitation of Yang-hyperactivity by the extrinsic factor 3. smaller excess Yin-hypoactivity with the loss of Yang-hyperactivity. And excess Yang-hyperactivity also has three variations. In my point of view, CVA, Hematemesis, Vommiting, Abdominal Pain, Gastric Dyscomfort has No.3 type and Asthmatic condition, Dysentery, Edema has No.1 type.

• Journal of the Korean Ceramic Society
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• v.36 no.7
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• pp.762-766
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• 1999

The crystal structure of A2+(Mg1/3Nb2/3)O3,(A2+=Sr2+ and Ca2+)ceramics was studied usig X-ray diffraction (XRD) and high resolution transmission electrion microscopy(HRTEM). Ba(Mg1/3Nb2/3)O3 (SMN) has the 1:2 ordered monoclinic structure which has the anti-phase tilt of octahedra. The type of tilting in SMN was considered to be a$^{\circ}$a$^{\circ}$c- or a­a­c$^{\circ}$ Ca(Mg1/3Nb2/3)O3 (CMN) also has the 1:2 ordered monoclinic structure which was distorted by the anti-phase tilt or in-phsae tilt of octahedra. A unit cell containing both the in-phase tilt axis and anti-phase tilt axis was not observed in the CMN. Therefore CMN has the mixed phase consisting of the 1:2 ordered monoclinic phase with anti-phase tilt of octahedra and the one with in -phase tilt of ocatahedra,. The anti-parallel shift of cation was also observed in the CMN.

• BMB Reports
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• v.56 no.2
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• pp.120-125
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• 2023

Karyopherin-α3 (KPNA3), a karyopherin-α isoform, is intimately associated with metastatic progression via epithelial-mesenchymal transition (EMT). However, the molecular mechanism underlying how KPNA3 acts as an EMT inducer remains to be elucidated. In this report, we identified that KPNA3 was significantly upregulated in cancer cells, particularly in triple-negative breast cancer, and its knockdown resulted in the suppression of cell proliferation and metastasis. The comprehensive transcriptome analysis from KPNA3 knockdown cells indicated that KPNA3 is involved in the regulation of numerous EMT-related genes, including the downregulation of GATA3 and E-cadherin and the up-regulation of HAS2. Moreover, it was found that KPNA3 EMT-mediated metastasis can be achieved by TGF-β or AKT signaling pathways; this suggests that the novel independent signaling pathways KPNA3-TGF-β-GATA3-HAS2/E-cadherin and KPNA3-AKT-HAS2/E-cadherin are involved in the EMT-mediated progress of TNBC MDA-MB-231 cells. These findings provide new insights into the divergent EMT inducibility of KPNA3 according to cell and cancer type.