• Title/Summary/Keyword: Weak area

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Comparison of masticatory efficiency according to Angle's classification of malocclusion

  • Bae, Jungin;Son, Woo-Sung;Kim, Seong-Sik;Park, Soo-Byung;Kim, Yong-Il
    • The korean journal of orthodontics
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    • v.47 no.3
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    • pp.151-157
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    • 2017
  • Objective: The objective of this study was to investigate the differences in masticatory efficiency among patients with different Angle's classes of malocclusion and to assess the correlation between masticatory efficiency and the occlusal contact area. Methods: The mixing ability index (MAI) was calculated for measuring masticatory efficiency of 61 adult patients according to Angle's classifications of malocclusion. The study included 25, 15, and 21 patients with Angle's Class I, II, and III malocclusions, respectively. Silicone interocclusal recording material was used to measure the occlusal contact area. Results: Both the MAI and occlusal contact area showed the highest average values in the Class I malocclusion group, followed by the Class II and Class III malocclusion groups. No significant difference was observed in the MAI values between the Class I and Class II malocclusion groups (p > 0.05), whereas a significant difference was observed between the Class I and Class III malocclusion groups (p < 0.01) and between the Class II and Class III malocclusion groups (p < 0.05). A weak positive correlation was also observed between the MAI and occlusal contact area (p < 0.01, $r^2=0.13$). Conclusions: The results of this study indicated that masticatory efficiency was the highest in patients with Angle's Class I malocclusion, followed by those with Angle's Class II and Angle's Class III malocclusions. Moreover, a weak positive correlation was observed between masticatory efficiency and the occlusal contact area.

Investigation of trace element contamination in steam sediments in the Chungnam coal mine area using geostatistical approach (지구 통계학적 방법에 의한 충남 탄전 지역 하상퇴적물의 미량원소 오염조사)

  • 황춘길
    • Economic and Environmental Geology
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    • v.32 no.1
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    • pp.63-72
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    • 1999
  • In order to examine the contamination levels of trace elements in stream sediments in the Chungnam coal mine area, stream sediment and water samples were collected and analyzed for trace elements. The pH of stream water was neutral or weak-alkaline and the mobility of metal in stream sediments was supposed to be low. From the result of cluster analysis, non-polluted sampling stations can be distinguished from polluted sampling stations influenced by mining activities. The trace element concentrations in sediments from non-polluted zone were considered to be the natural backround concentrations of this area. The trace element concentrations in sediment samples from the mining area were higher than those from non-polluted area, and contaminated area of enriched trace element levels need to be properly managed. From the results of discriminant and regression analyses, concentrations of Cd, Cu, Pb AND zN and predicted values of Be, Mo, and Ni in Chungnam coal mine area were found to be lower than those in metal mining areas in Korea.

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A Study on the Vernacular Dwellings in Noksan area, Kinhae (김해녹산지역 전통주거의 조사연구)

  • KyungTaiSeo
    • Journal of the Korean housing association
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    • v.4 no.1
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    • pp.5-16
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    • 1993
  • This paper tries to find out the characteristics of the vernacular dwellings in Noksan area which has been a part of Kaya cultural realm. Through the analyses of its environments and several practical unit plans. The characteristic of the vernacular dwellings in thes arer are as below. The dwellings has been transfigured form [Omaksari] hut which is generally the smallest house form in Korea. The noticeable vernacular hut in this area is smallest 4-kan double-wing plan which is irregular 전 shape, but they call it single wing and 2-kan plan. Leed which can be obtained easily in thes area is used on roof and in wall. Timbers used in constrution are very slim or rather weak, but they were treated carafully. The chimney form in this area seems the results of minimizing of their being from the invasion of Japanese pirate, but also it seems an effective method of heat control. In conclusion, we cannot deny that the house form of this area seems affected by its exclusive natural and social environments.

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대전지역 약수의 수질특성과 관리방안

  • 정찬호;김은지;문병진
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.09a
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    • pp.15-18
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    • 2001
  • Sixty natural springs and wells used as community facilities for drinking water are developed along mountain climbing way of suburban area and residential area in Daejeon City. In this study, the seasonal variation of their water quality and hydrochemical characteristics were investigated. Some natural springs are vulnerable to bacilli contamination because of their short residence time and shallow circulation in subsurface environment. The waters show hydrochemical types of Ca-HCO$_3$ and Na-HCO$_3$, and are characterized by low electrical conductance and weak acidic pH.

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The Exchange Bias of NiO/NiFe Thin Eilm by the Measurement of Anisotropic Mngnetoresistance (이방성 자기저항측정을 이용한 NiO/NiFe 박막의 교환결합연구)

  • Kim, Jong-Kee;Kim, Sun-Wook;Lee, Ky-Am;Lee, Sang-Suk;Hwang, Do-Guwn
    • Journal of the Korean Magnetics Society
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    • v.12 no.4
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    • pp.143-148
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    • 2002
  • We report an experimental evidence of coexistence of the strong and weak exchange couplings in unidirectional NiO/NiFe (antiferromagneticlferromagnetic) bilayer thin films. The exchange bias was measured by VSM and AMR techniques and then, analyzed into the strong and weak exchange couplings by means of a regression method. In NiO(60nm)/NiFe(10nm) film, the ratio of the weak exchange coupling field over the average exchange coupling field was found to be almost unchanged within it range from 0.2 to 0.4 irrespective to the strength of an applied field. However, the ratio increased among the samples with decreasing the average exchange coupling field due to the increment of the weak exchange coupling area.

A Study on a Proposal-scheme for Evacuation Routes Planning at a Large-scale Disaster in a Historic Preservation Area

  • Mishima, Nobuo;Miyamoto, Naomi
    • Proceedings of the Korea Contents Association Conference
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    • 2012.05a
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    • pp.193-194
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    • 2012
  • Most of the Historic Preservation Areas are very weak to fire disasters. The aim of this study is to build a proposal-scheme for evacuation routes planning at a large-scale disaster in a historic preservation area. The study area is a preservation area called "Hizen-Hama-Shuku" which has many straw-roofed wooden houses in Kashima city, Japan. To achieve this aim, outline of the scheme is discussed. The proposal-scheme of evacuation routes consists of objectives to propose, target time to evacuate for the refuge place, evaluation method, and procedures. The existing condition and the measures are evaluated using the software "SimTread".

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Fluorescence of Tongue Coat - Mechanism of Tongue Coat Fluorescence and Suggestions on Development of Digital Tongue Diagnosis System - (설태의 형광특성 - 설태 형광현상의 발현기전 소개 및 제안 -)

  • Kim, Ji-Hye;Nam, Dong-Hyun
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.15 no.1
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    • pp.47-54
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    • 2011
  • In traditional Korean medicine, inspection of the tongue is an important method of making medical diagnoses and determining prognosis. We surveyed the fluorescence characteristics of the tongue coat in the ultraviolet light. The tongue coat comprises micro-organisms, blood metabolites, leukocytes from periodontal pockets, large amounts of desquamated epithelial cells released from the oral mucosa and different nutrients. In the ultraviolet light tissues of the oral cavity generally emit weak red or green fluorescence, which is not easily seen by the human eye, but is readily detected. This fluorescence has been proved to be due to the production of porphyrins by oral micro-organisms. While the composition of motile micro-organisms on the dorsum of the tongue is not constant, variations also occur persistingly in the fluorescence characteristics of the tongue coat. But because live bacteria contain a variety of intracellular biomolecules that have specific excitation and emission wavelength spectra characterizing their intrinsic fluorescence, the tongue coat emits fluorescence. the tongue itself, on the other hand, emits very weak or not fluorescence. In conclusion, we suggests that the uncoated tongue area be eliminated from the coated tongue area with the difference between the fluorescence characteristics of the tongue and that of the tongue coat.

Numerical Simulation for Recirculation of Air Mass in the Coastal Region Using Lagrangian Particle Dispersion Model (라그랑지안 입자확산모델을 이용한 광양만 권역에서의 공기괴 재순환현상 수치모의)

  • Lee, Hwa-Woon;Lee, Hyun-Mi;Lee, Soon-Hwan;Choi, Hyun-Jung
    • Journal of Environmental Science International
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    • v.19 no.2
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    • pp.157-170
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    • 2010
  • Air mass recirculation is a common characteristic in the coastal area as a result of the land-sea breeze circulation. This study simulates the recirculation of air mass over the Gwangyang Bay using WRF-FLEXPART and offers a basic information about the effective domain size that can reflect recirculation. For this purpose, WRF is set up four nested domains and three cases are selected. Subsequently FLEXPART is operated on the basis of WRF output. During the clear summer days with weak wind speed, particles that emitted from Yeosu national industrial complex and Gwangyang iron works flow into emission sources because of the land-sea breeze. When land-sea breeze is strengthen, the recirculation phenomena appears clearly. However particles aren't recirculated under weak synoptic condition. Also plume trajectory is analyzed and as a consequence, the smallest domain area have to be multiplied by 1.3 to understand recirculated dispersion pattern of particles.

Automatic Identification of Fiducial Marks Based on Weak Constraints

  • Cho, Seong-Ik;Kim, Kyoung-Ok
    • Korean Journal of Remote Sensing
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    • v.19 no.1
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    • pp.61-70
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    • 2003
  • This paper proposes an autonomous approach to localize the center of fiducial marks included in aerial photographs without precise geometric information and human interactions. For this localization, we present a conceptual model based on two assumptions representing symmetric characteristics of fiducial area and fiducial mark. The model makes it possible to locate exact center of a fiducial mark by checking the symmetric characteristics of pixel value distribution around the mark. The proposed approach is composed of three steps: (a) determining the symmetric center of fiducial area, (b) finding the center of a fiducial mark with unit pixel accuracy, and finally (c) localizing the exact center up to sub-pixel accuracy. The symmetric center of the mark is calculated tv successively applying three geometric filters: simplified ${\nabla}^2$G (Laplacian of Gaussian) filter, symmetry enhancement filter, and high pass filter. By introducing a self-diagnosis function based on the self-similarity measurement, a way of rejecting unreliable cases of center calculation is proposed, as well. The experiments were done with respect to 284 samples of fiducial marks composed of RMK- and RC-style ones extracted from 51 scanned aerial photographs. It was evaluated in the visual inspection that the proposed approach had resulted the erroneous identification with respect to only one mark. Although the proposed approach is based on weak constraints, being free from the exact geometric model of the fiducial marks, experimental results showed that the proposed approach is sufficiently robust and reliable.

Efficient method of Searching PI Code on RDS System (RDS System 에서의 효율적인 PI code 검출 기법에 관한 연구)

  • Cho, Chung-bum;Kim, Yound-cil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.112-115
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    • 2009
  • PI code searching method of RDS(Radio Data System) are unique method of maintain desired channel on moving machine like vehicle. Efficient and fast PI code search method are researching on the all of RDS related systems for both find more better channel before Original channel signal go to bad and find desired good signal quickly when get out of Weak signal Area. But Embedded system has limited environment like memory size, so It is very difficult to apply many well known PI code searching method. This thesis suggests simple and effective method of searching PI code, considering a Embedded System Environment.

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