• Title/Summary/Keyword: Graduate School Model

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Induction of Oral Tolerance to Japanese Cedar Pollen

  • Kim, Joung-Hoon;Mun, Yeun-Ja;Ahn, Seong-Hun;Park, Joung-Suk;Woo, Won-Hong
    • Archives of Pharmacal Research
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    • v.24 no.6
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    • pp.557-563
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    • 2001
  • Oral tolerance is thought to play a role in preventing allergic responses and immune-mediated diseases. An improved mouse model of the oral tolerance to Japanese cedar pollen (JCP) as antigen was developed in order to detect induction of the tolerance, and the immunological characteristics of this model were also elucidated. Oral tolerance was induced by C3H/ HeN mice given an oral administration of 10 mg JCP 7 days before immunization with an i.p. injection of 0.1 mg JCP in complete Freunds adjuvant (CFA). The effects of oral JCP on systemic immunity were assessed by enzyme-linked immunosorbent assay (ELISA) of immunoglobulin (Ig) levels in serum collected on day 7 or 14 after immunization. Oral tolerance to JCP was adequately induced on day 7 after immunization and was more effective in C3H/HeN mice than in BALB/c mice. The tolerance was primarily concerned with the decreased serum levels of antigen-specific IgG. In these mice, oral administration of JCP also suppressed various immune responses to the antigen including delayed-type hypersensitivity (DTH), total Igl level and anti-JCP IgGl level. The suppression of these immune responses by the oral antigen was associated with a significant reduction in interleukin-4 (IL-4) production. These findings therefore indicate that this C3H/HeN mice model has potential use in detecting the induction of oral tolerance by JCP and suggest that this tolerance model may be effective in the treatment and prevention of allergic responses caused by the antigen.

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The stress analysis of supporting tissues according to crown restorative materials in Brånemark osseointegrated implant (Brånemark 골유착성 매식체의 금관 수복재료에 따른 지지조직의 응력분석)

  • Jeong, Gwan-Ho;Bae, Tae Seong;Song, Kwang-Yeob;Park, Charn-Woon
    • The Journal of Korean Academy of Prosthodontics
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    • v.28 no.2
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    • pp.199-215
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    • 1990
  • This study was to analyze the stress distribution of implant and supporting tissue in $Br{\aa}nemark$ osseointegration implant. The analysis has been conducted by using the axisymmetric finite element method and type of model according to crown material. Tests have been performed at 1 kg load on central fossa of crown portion. Each type of model was designed differently according to crown material. 1) Porcelain fused to metal crown(Model A) 2) Composite resin veneered crown(Model B) 3) Acrylic resin veneered crown(Model C) 4) Type III gold crown(Model D) The displacements and stresses of implant and supporting structures were analyzed to investigate the influence of the type of crown material. The results were obtained as follows : 1. Displacement of implant was shown uniformly downward displacement in all models and abutments were observed distally downward displacement. 2. In supporting tissues, stress was concentrated on the crest of compact bone and the spongy bone below implant. 3. The PFM and the type III gold crown showed the largest concentration of stress at the crest of compact bone and the spongy bone below implant, respectively. Acrylic resin artificial teeth and composite resin veneered crown indicated almost the same distribution of stress. 4. The gold screw, the abutment screw and the top of abutment showed the concentration of stress in implants of every model.

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A Choice-Based Competitive Diffusion Model with Applications to Mobile Telecommunication Service Market in Korea (선택관점의 경쟁확산모형과 국내 이동전화 서비스 시장에의 응용)

  • Jun, Duk-Bin;Kim, Seon-Kyoung;Cha, Kyung-Cheon;Park, Yoon-Seo;Park, Myoung-Hwan;Park, Young-Sun
    • Journal of Korean Institute of Industrial Engineers
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    • v.27 no.3
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    • pp.267-273
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    • 2001
  • While forecasting sales of a new product is very difficult, it is critical to market success. This is especially true when other products have a highly negative influence on the product because of competition effect. In this paper, we develop a choice-based competitive diffusion model and apply to the case where two digital mobile telecommunication services, that is, digital cellular and PCS services, compete. The basic premise is that demand patterns result from choice behavior, where customers choose a product to maximize their utility. In comparison with Bass-type competitive diffusion models, our model provides superior fitting and forecasting performance. The choice-based model is useful in that it enables the description of such competitive environments and provides the flexibility to include marketing mix variables such as price and advertising.

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AERODYNAMIC ANALYSIS AND EXPERIMENTAL TEST FOR 4-BLADED VERTICAL AXIS WIND-TURBINE USING LARGE-EDDY SIMULATION (LES) TURBULENCE MODEL (LES 난류모델을 이용한 4엽형 수직축 풍력발전기 공력해석 및 실험)

  • Ryu, G.J.;Kim, D.H.;Choo, H.H.;Shim, J.P.
    • Journal of computational fluids engineering
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    • v.17 no.3
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    • pp.11-17
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    • 2012
  • In this study, aerodynamic analyses have been conducted for 4-Bladed Vertical-Axis Wind Turbine (VAWT) configuration and the results are compared with experimental data. Reynolds-averaged Navier-Stokes equation with LES turbulence model is solved for unsteady flow problems. In addition, the computation results by standard k-${\omega}$ and SST k-${\omega}$ turbulence models are also presented and compared. An experiment model of 4-Bladed VAWT model has been designed and constructed herein. Experimental tests for aerodynamic performance of the present VAWT model are practically conducted using the vehicle mounted testing system. Comparison results between the experiment and the computational fluid dynamics (CFD) analyses are presented in order to show the accuracy of CFD analyses using the different turbulent models.

Two-Stage forecasting Using Change-Point Detection and Artificial Neural Networks for Stock Price Index

  • Oh, Kyong-Joo;Kim, Kyoung-Jae;Ingoo Han
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2000.11a
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    • pp.427-436
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    • 2000
  • The prediction of stock price index is a very difficult problem because of the complexity of the stock market data it data. It has been studied by a number of researchers since they strong1y affect other economic and financial parameters. The movement of stock price index has a series of change points due to the strategies of institutional investors. This study presents a two-stage forecasting model of stock price index using change-point detection and artificial neural networks. The basic concept of this proposed model is to obtain Intervals divided by change points, to identify them as change-point groups, and to use them in stock price index forecasting. First, the proposed model tries to detect successive change points in stock price index. Then, the model forecasts the change-point group with the backpropagation neural network (BPN). Fina1ly, the model forecasts the output with BPN. This study then examines the predictability of the integrated neural network model for stock price index forecasting using change-point detection.

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A method for mandibular dental arch superimposition using 3D cone beam CT and orthodontic 3D digital model

  • Park, Tae-Joon;Lee, Sang-Hyun;Lee, Ki-Soo
    • The korean journal of orthodontics
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    • v.42 no.4
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    • pp.169-181
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    • 2012
  • Objective: The purpose of this study was to develop superimposition method on the lower arch using 3-dimensional (3D) cone beam computed tomography (CBCT) images and orthodontic 3D digital modeling. Methods: Integrated 3D CBCT images were acquired by substituting the dental portion of 3D CBCT images with precise dental images of an orthodontic 3D digital model. Images were acquired before and after treatment. For the superimposition, 2 superimposition methods were designed. Surface superimposition was based on the basal bone structure of the mandible by surface-to-surface matching (best-fit method). Plane superimposition was based on anatomical structures (mental and lingual foramen). For the evaluation, 10 landmarks including teeth and anatomic structures were assigned, and 30 times of superimpositions and measurements were performed to determine the more reproducible and reliable method. Results: All landmarks demonstrated that the surface superimposition method produced relatively more consistent coordinate values. The mean distances of measured landmarks values from the means were statistically significantly lower with the surface superimpositions method. Conclusions: Between the 2 superimposition methods designed for the evaluation of 3D changes in the lower arch, surface superimposition was the simpler, more reproducible, reliable method.

AKARI AND SPINNING DUST: INVESTIGATING THE NATURE OF ANOMALOUS MICROWAVE EMISSION VIA INFRARED SURVEYS

  • Bell, Aaron C.;Onaka, Takashi;Doi, Yasuo;Sakon, Itsuki;Usui, Fumihiko;Sakon, Itsuki;Ishihara, Daisuke;Kaneda, Hidehiro;Giard, Martin;Wu, Ronin;Ohsawa, Ryou;Mori-Ito, Tamami;Hammonds, Mark;Lee, Ho-Gyu
    • Publications of The Korean Astronomical Society
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    • v.32 no.1
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    • pp.97-99
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    • 2017
  • Our understanding of dust emission, interaction, and evolution, is evolving. In recent years, electric dipole emission by spinning dust has been suggested to explain the anomalous microwave excess (AME), appearing between 10 and 90 Ghz. The observed frequencies suggest that spinning grains should be on the order of 10nm in size, hinting at polycyclic aromatic hydrocarbon molecules (PAHs). We present data from the AKARI/Infrared Camera (IRC) due to its high sensitivity to the PAH bands. By inspecting the IRC data for a few AME regions, we find a preliminary indication that regions well-fitted by a spinning-dust model have a higher $9{\mu}m$ than $18{\mu}m$ intensity vs. non-spinning-dust regions. Ongoing efforts to improve the analysis by using DustEM and including data from the AKARI Far Infrared Surveyor (FIS), IRAS, and Planck High Frequency Instrument (HFI) are described.

Improvement of flood simulation accuracy based on the combination of hydraulic model and error correction model

  • Li, Li;Jun, Kyung Soo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.258-258
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    • 2018
  • In this study, a hydraulic flow model and an error correction model are combined to improve the flood simulation accuracy. First, the hydraulic flow model is calibrated by optimizing the Manning's roughness coefficient that considers spatial and temporal variability. Then, an error correction model were used to correct the systematic errors of the calibrated hydraulic model. The error correction model is developed using Artificial Neural Networks (ANNs) that can estimate the systematic simulation errors of the hydraulic model by considering some state variables as inputs. The input variables are selected using parital mutual information (PMI) technique. It was found that the calibrated hydraulic model can simulate flood water levels with good accuracy. Then, the accuracy of estimated flood levels is improved further by using the error correction model. The method proposed in this study can be used to the flood control and water resources management as it can provide accurate water level eatimation.

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Effect of Buddleja officinalis in Diabetic Atherosclerotic Mouse Model Using High Fat Diet (고지방 식이로 유도된 당뇨병성 죽상경화 마우스 모델에서 밀몽화의 효능 연구)

  • Hwang, Sun-Mi;Lee, Yun-Jung;Kim, Eun-Ju;Kim, Hye-Yoom;Li, Xiang;Choi, Yong-Jun;Cho, Nam-Geun;Lee, Ho-Sub;Kang, Dae-Gill
    • The Korea Journal of Herbology
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    • v.24 no.4
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    • pp.55-62
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    • 2009
  • Objectives : This study was designed to investigate the effects of an aqueous extract from Buddleja officinalis Maxim (ABO) on vascular dysfunction in low-density lipoprotein receptor deficient (LDLr KO) mice. Methods : Present study showed that LDLr KO mice were fed a high fat diet consisting of 60 kcal% fat, with or without 200 mg/day/kg ABO of diet, for 14 weeks. Results : High fat diet-LDLr KO mice were treated with ABO were completely normalized by lowering glucose. ABO reduced intima/media thickness in a high fat diet-LDLr KO mice without affecting plasma cholesterol and triglyceride levels. ABO caused endothelium-dependent relaxation in the acetylcholine-precontracted aorta of high fat diet-LDLr KO mice. ABO increased eNOS expression, while decreased cell adhesion molecules expression in high fat diet-LDLr KO mice. Conclusions : In conclusion, chronic treatment with ABO improved hyperglycemia and endothelium-dependent vascular relaxation as well as exhibited anti-inflammatory effect in diabetic atherosclerotic mouse model, independent of effects on plasma lipids.

Quality Assessment Model for Practical Wearable Computers (실용적 웨어러블 컴퓨터 품질평가모델)

  • Oh, Cheon-Seok;Choi, Jae-Hyun;Kim, Jong-Bae;Park, Jea-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39B no.12
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    • pp.842-855
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    • 2014
  • Recently, the progress of smart phone market has retarded by oversupply therefore wearable computer has been the focus of new growth engine. Wearable computing system is a complex fusion of a variety of technologies such as wireless network, embedded, sensor and new material. Because these technologies involves utilization and mobility in addition to quality characteristic in existing software, application of ISO/IEC 9126 is not perfect when assessing quality of wearable computer. In this study, author suggested new quality assessment model for wearable computer by sorting quality attribute in ISO/IEC 9126 and adding new quality attribute. For this, author investigated features and functional requirements related to wearable computer. and then author suggested quality standard and metrics by identifying quality characteristic. Author confirmed practicality of quality assessment model by using suggested model in scenario and comparing quality assessment of three goods such as company S, L, G. This quality assessment model is expected to use guidelines for assessing quality of wearable computer.