• Title/Summary/Keyword: preS region

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A Study on the Pre-Classification of Handwritten Hangeul Characters Using Partial Separation and Recognition of Initial Consonants (초성자소분리 인식에 의한 필기 한글문자의 대분류에 관한 연구)

  • 안석출;김명기
    • Journal of the Korean Graphic Arts Communication Society
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    • v.6 no.1
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    • pp.41-57
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    • 1988
  • Recently, it Is required to develop OCR(Optical Character Reader) along with the progress of the information processing system for Hangeul. Characters have to be recognized clearly so that OCR can be applied, Structure analysis method and lump method are used for the recognition of characters, and OCR is now available for the recognition of printed characters and handwritten alphanumeric characters having simple structure by them However, It is known that there should be much more study on the development of handwritten Hangout's OCR. This paper proposed a new method for the handwritten Hangout character recognition. The units of Initial consonant of Hangout are separated and then recognized from the utilization of the position- Information of Hangeul's units from the normalized patterns using the regression line theory. It is carried out for the extraction of the block which exists in the virtual Initial consonant region from the normalized input patterns and the calculation on maximum value (${\beta}$) of likelihood after comparing the features of separated subpattern with the initial consonant dictionary.

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Seasonal Variability of Sonic Layer Depth in the Central Arabian Sea

  • Bhaskar, TVS Udaya;Swain, Debadatta;Ravichandran, M
    • Ocean Science Journal
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    • v.43 no.3
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    • pp.147-152
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    • 2008
  • The seasonal variability of sonic layer depth (SLD) in the central Arabian Sea (CAS) (0 to $25^{\circ}N$ and $62-66^{\circ}E$) was studied using the temperature and salinity (T/S) profiles from Argo floats for the years 2002-2006. The atmospheric forcing responsible for the observed changes was explored using the meteorological data from NCEP/NCAR and Quickscat winds. SLD was obtained from sound velocity profiles computed from T/S data. Net heat flux and wind forcing regulated SLD in the CAS. Up-welling and down-welling (Ekman dynamics) associated with the Findlater Jet controlled SLD during the summer monsoon. While in winter monsoon, cooling and convective mixing regulated SLD in the study region. Weak winds, high insolation and positive net heat flux lead to the formation of thin, warm and stratified sonic layer during pre and post summer monsoon periods, respectively.

Prediction of Roll Force Profile in Cold Rolling - Part I : Development of a Mathematical Model (냉간 압연에서 압하력 분포 예측 - Part I : 수식 모델 개발)

  • Nam, S.Y.;Hwang, S.M.
    • Transactions of Materials Processing
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    • v.28 no.4
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    • pp.190-196
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    • 2019
  • The capability of accurately predicting the roll force profile across a strip in the bite zone in cold rolling process is vital for the calculation of strip profile. This paper presents a derivation of a precision mathematical model for predicting variations in the roll force across a strip in cold rolling. While the derivation is based on an approximate 3-D theory of rolling, this mathematical model also considers plastic deformation in the pre-deformation region which is located close to the roll entrance before the strip enters the bite zone. Finally, the mathematical model is expressed as a boundary value problem, and it predicts the roll force profile and tension profile in addition to lateral plastic strain profile.

Patient-specific implants for maxillofacial defects: challenges and solutions

  • Alasseri, Nasser;Alasraj, Ahmed
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.42
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    • pp.15.1-15.8
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    • 2020
  • Background: Reconstructing maxillofacial defects is quite challenging for most surgeons due to the region's complex anatomy and cosmetic and functional effects on patients. The use of pre-made alloplastic implants and autogenous grafts is often associated with resorption, infection, and displacement. Recent technological advances have led to the use of custom computer-designed patient-specific implants (PSIs) in reconstructive surgery. This study describes our experience with PSI, details the complications we faced, how to overcome them, and finally, evaluates patient satisfaction. Case presentation: Six patients underwent reconstruction of various maxillofacial defects arising due to different etiologies using PSI. A combined total of 10 implants was used. PEEK was used to fabricate 8, while titanium was used to fabricate 2. No complications were seen in any patient both immediately post-op and in subsequent follow-ups. All patients reported a high level of satisfaction with the final result both functionally and cosmetically. Conclusion: The use of computer-designed PSI enables a more accurate reconstruction of maxillofacial defects, eliminating the usual complications seen in preformed implants and resulting in higher patient satisfaction. Its main drawback is its high cost.

A Study on Promoting the Consumption of Sangju-Dried Persimmons as Functional Food through Scientific Inquiry (약선(藥膳)의 과학적 원리를 통한 상주곶감 소비촉진 방안 연구)

  • Choi, Jung-Hoon;Kim, Chang-Man
    • Journal of Environmental Science International
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    • v.25 no.4
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    • pp.543-556
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    • 2016
  • Sangju, a city in the North Gyeongsang Province, is well known as "Three Whites", representing its three main agricultural products: rice, silkworm, and dried persimmons. Therefore, development of a variety of dishes or products that can promote the consumption of dried persimmons is an urgent requirement for this region. This study was designed to provide fundamental information for revitalizing community-based specialized agriculture through scientific inquiry into medicinal foods and to develop a medicinal food menu based on the results of previous research and pre-survey. The pre-survey results and incompatibility revealed that palatability influenced people's decision to consume dried persimmons far more than pharmacological functionality. Therefore, palatability played an important part in the development of dried persimmon puddings with acceptable texture. These dishes are in high demand as they suit the tastes of variety of consumers. The inclusion of various additives lowered the sugar content in the developed foods and made the products alkalescent (pH > 7), thereby improving functionality. Unique color and flavor additives were also important criteria that determined the selection attributes of the developed medicinal foods. In addition, the additives had a positive effect on the fragrance and texture of the foods. In conclusion, the results suggested that use of additives provides significant advantages in promoting the consumption of Sangju-dried persimmons by improving both functionality and palatability.

Modeling the Influence of Gas Pressure on Droplet Impact Using a Coupled Gas/liquid Boundary Element Method

  • Park, Hong-Bok;Yoon, Sam S.;Jepsen Richard A.;Heister Stephen D.
    • Journal of ILASS-Korea
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    • v.11 no.2
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    • pp.89-97
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    • 2006
  • An inviscid axisymmetric model capable of predicting droplet bouncing and the detailed pre-impact motion, influenced by the ambient pressure, has been developed using boundary element method (BEM). Because most droplet impact simulations of previous studies assumed that a droplet was already in contact with the impacting substrate at the simulation start, the previous simulations could not accurately describe the effect of the gas compressed between a failing droplet and the impacting substrate. To properly account for the surrounding gas effect, an effect is made to release a droplet from a certain height. High gas pressures are computationally observed in the region between the droplet and the impact surface at instances just prior to impact. The current simulation shows that the droplet retains its spherical shape when the surface tension energy is dominant over the dissipative energy. When increasing the Weber number, the droplet surface structure is highly deformed due to the appearance of the capillary waves and, consequently, a pyramidal surface structure is formed; this phenomenon was verified with our experiment. Parametric studies using our model include the pre-impact behavior which varies as a function of the Weber number and the surrounding gas pressure.

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Efficient Processing using Static Validity Circle for Continuous Skyline Queries (연속적인 스카이라인 질의의 정적 유효 영역을 이용한 효율적인 처리)

  • Li, Zhong-He;Park, Young-Bae
    • Journal of KIISE:Databases
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    • v.33 no.6
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    • pp.631-643
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    • 2006
  • Moving objects in a mobile environment to change their position based on the change of time require a query with their position as a basis. Efficient Regional Decision for Continuous Skyline Queries requires objectively pre-calculating the OSR(Optimal Skyline Region) regardless of the speed and direction of the moving objects. It proposes techniques to reduce the frequency of continuous queries by choosing a VCircle(Validity Circle) as safe location which has radius of the distance to the closest region with position on the moving object at center. But, a VCircle's area varies based on the Moving object's position from first marked time of continuous query. Therefore, the frequency of its continuous query is variable and also when the object moves inside of OSR, query can re-occur frequently In this paper, we suggest a technique of selecting an IVCircle(Interior Validity Circle) in a Skyline Region as the static Safe Region using the characteristics of the OSR. An Interior IVCircle can be calculated in advance when the OSR is decided. Our experiment shows that the frequency of using IVcircle as safe region reduced than that of using VCircle as safe region by 52.55%.

An Adaptive Thresholding of the Nonuniformly Contrasted Images by Using Local Contrast Enhancement and Bilinear Interpolation (국소 영역별 대비 개선과 쌍선형 보간에 의한 불균등 대비 영상의 효율적 적응 이진화)

  • Jeong, Dong-Hyun;Cho, Sang-Hyun;Choi, Heung-Moon
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.12
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    • pp.51-57
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    • 1999
  • In this paper, an adaptive thresholding of the nonuniformly contrasted images is proposed through using the contrast pre-enhancement of the local regions and the bilinear interpolation between the local threshold values. The nonuniformly contrasted image is decomposed into 9${\times}$9 sized local regions, and the contrast is enhanced by intensifying the gray level difference of each low contrasted or blurred region. Optimal threshold values are obtained by iterative method from the gray level distribution of each contrast-enhanced local region. Discontinuities are reduced at the region of interest or at the characters by using bilinear interpolation between the neighboring threshold surfaces. Character recognition experiments are conducted using backpropagation neural network on the characters extracted from the nonuniformly contrasted document, PCB, and wafer images binarized through using the proposed thresholding and the conventional thresholding methods, and the results prove the relative effectiveness of the proposed scheme.

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SEJONG OPEN CLUSTER SURVEY (SOS) - V. THE ACTIVE STAR FORMING REGION SH 2-255 - 257

  • LIM, BEOMDU;SUNG, HWANKYUNG;HUR, HYEONOH;LEE, BYEONG-CHEOL;BESSELL, MICHAEL S.;KIM, JINYOUNG S.;LEE, KANG HWAN;PARK, BYEONG-GON;JEONG, GWANGHUI
    • Journal of The Korean Astronomical Society
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    • v.48 no.6
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    • pp.343-355
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    • 2015
  • There is much observational evidence that active star formation is taking place in the Hii regions Sh 2-255 – 257. We present a photometric study of this star forming region (SFR) using imaging data obtained in passbands from the optical to the mid-infrared, in order to study the star formation process. A total of 218 members were identified using various selection criteria based on their observational properties. The SFR is reddened by at least E(B −V ) = 0.8 mag, and the reddening law toward the region is normal (RV = 3.1). From the zero-age main sequence fitting method it is confirmed that the SFR is 2.1 ± 0.3 kpc from the Sun. The median age of the identified members is estimated to be about 1.3 Myr from a comparison of the Hertzsprung-Russell diagram (HRD) with stellar evolutionary models. The initial mass function (IMF) is derived from the HRD and the near-infrared (J, J −H) color-magnitude diagram. The slope of the IMF is about Γ = −1.6 ± 0.1, which is slightly steeper than that of the Salpeter/Kroupa IMF. It implies that low-mass star formation is dominant in the SFR. The sum of the masses of all the identified members provides the lower limit of the cluster mass (169M). We also analyzed the spectral energy distribution (SED) of pre-main sequence stars using the SED fitting tool of Robitaille et al., and confirm that there is a significant discrepancy between stellar mass and age obtained from two different methods based on the SED fitting tool and the HRD.

Time-Varying Seismogenic Coulomb Electric Fields as a Probable Source for Pre-Earthquake Variation in the Ionospheric F2-Layer

  • Kim, Vitaly P.;Hegai, Valery V.;Liu, Jann Yenq;Ryu, Kwangsun;Chung, Jong-Kyun
    • Journal of Astronomy and Space Sciences
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    • v.34 no.4
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    • pp.251-256
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    • 2017
  • The electric coupling between the lithosphere and the ionosphere is examined. The electric field is considered as a timevarying irregular vertical Coulomb field presumably produced on the Earth's surface before an earthquake within its epicentral zone by some micro-processes in the lithosphere. It is shown that the Fourier component of this electric field with a frequency of 500 Hz and a horizontal scale-size of 100 km produces in the nighttime ionosphere of high and middle latitudes a transverse electric field with a magnitude of ~20 mV/m if the peak value of the amplitude of this Fourier component is just 30 V/m. The time-varying vertical Coulomb field with a frequency of 500 Hz penetrates from the ground into the ionosphere by a factor of ${\sim}7{\times}10^5$ more efficient than a time independent vertical electrostatic field of the same scale size. The transverse electric field with amplitude of 20 mV/m will cause perturbations in the nighttime F region electron density through heating the F region plasma resulting in a reduction of the downward plasma flux from the protonosphere and an excitation of acoustic gravity waves.