• 제목/요약/키워드: Excess parameters

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Analysis of Streamflow Characteristics of Boryeong-dam Watershed using Global Optimization Technique by Infiltraion Methods of CAT (CAT 모형의 침투해석방법별 전역최적화기법을 이용한 보령댐 유역의 유출 특성 변화 분석)

  • Park, Sanghyun;Kim, Hyeonjun;Jang, Cheolhee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.2
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    • pp.412-424
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    • 2019
  • In this study, the changes of the streamflow characteristics of the watershed were analysed depending on the infiltration methods of CAT. The study area, Boryeong-dam watershed located in Chungcheongnam-do area, has been suffered from severe drought in recent years and stabilized regarding on the storage rate through efforts such as constructing a channel connecting the upstream of Boryeong-dam from the downstream of the Geum river. In this study, the effects of soil infiltration parameters on the watershed streamflow characteristics were analyzed by the infiltration methods of CAT such as Rainfall Excess, Green&Ampt and Horton. And the parameter calibrations were conducted by SCEUA-P, a global optimization technique module of the PEST, the package for parameter optimization and uncertainty analysis, to compare the yearly variations of soil parameters for infiltration methods of CAT. In addition, the streamflow characteristics were analyzed for three infiltration methods by applying three different scenarios, such as applying calibrated parameters for every years to simulate the model for each years, applying calibrated parameters for the entire period to simulate the model for entire period, and applying the average value of yearly calibrated parameters to simulate the model for entire period.

A Study on the Stability of Explicit FE Analysis in the Sheet Metal Forming Analysis (박판 성형에서의 외연적 유한요소법의 안정성과 내연적 해석법과의 비교)

  • 심현보;전성문;손기찬
    • Transactions of Materials Processing
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    • v.9 no.3
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    • pp.293-303
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    • 2000
  • Recent developments of Fe technology make it possible to apply CAD/CAE/CAM techniques successfully to the stamping die design among the automotive parts industries. Those successful applications are greatly attributable to the development of commercial S/W. Up to now most commercial S/W for the analysis of sheet metal forming is based on the dynamic explicit algorithm. The main characteristics of dynamic explicit algorithm is that there is no convergence problem if the time increment is taken less than the stability limit. The stability of the analysis is guaranteed in the commercial code, since the adequate time increment is computed from the so called "Courant Condition". However excess computing time is often pointed out in the dynamic explicit analysis according to the characteristics of process parameters taken. In the study, various parameters that may affect the stability and the method how to improve computational efficiency of analysis have been investigated.estigated.

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Effects of Material Anisotropy on Ultrasonic Beam Propagation: Diffraction and Beam Skew

  • Jeong, Hyun-Jo;Schmerr, W.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.26 no.3
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    • pp.198-205
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    • 2006
  • The necessity of nondestructively inspecting austenitic steels, fiber-reinforced composites, and other inherently anisotropic materials has stimulated considerable interest in developing beam models for anisotropic media. The properties of slowness surface playa key role in the beam models based on the paraxial approximation. In this paper, we apply a modular multi-Gaussian beam (MMGB) model to study the effects of material anisotropy on ultrasonic beam profile. It is shown that the anisotropic effects of beam skew and excess beam divergence enter into the MMGB model through parameters defining the slope and curvature of the slowness surface. The overall beam profile is found when the quasilongitudinal(qL) beam propagates in the symmetry plane of transversely isotropic austenitic steels. Simulation results are presented to illustrate the effects of these parameters on ultrasonic beam diffraction and beam skew. The MMGB calculations are also checked by comparing the anisotropy factor and beam skew angle with other analytical solutions.

PHOTOELECTRIC OBSERVATIONS OF EXTREMELY YOUNG OPEN CLUSTERS

  • Kwon, Suk-Minn;Lee, See-Woo
    • Journal of The Korean Astronomical Society
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    • v.16 no.1
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    • pp.7-17
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    • 1983
  • During the period between January and November in 1982, UBV photoelectric observations were made for 48 stars in NGC 2264, 66 stars in IC 1805 and 22 stars in IC 348. From these observations, various physical parameters such as distance, mean color excess, total-to-selective extinction ratio and mean age of the clusters were determined. Making use of these parameters, the star formation rates were examined for IC 348 and NGC 2264. The overall formation rate is found to be increase rapidly during the period of the active star formation. The age spread (ranging from $5\times10^6$ yrs to $10^7$ yrs) of stars in a given cluster appears to be real which occurs in the extremely young open clusters.

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FINITE ELEMENT MODEL TO STUDY TWO DIMENSIONAL UNSTEADY STATE CYTOSOLIC CALCIUM DIFFUSION

  • Tewari, Shivendra Gajraj;Pardasani, Kamal Raj
    • Journal of applied mathematics & informatics
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    • v.29 no.1_2
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    • pp.427-442
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    • 2011
  • Calcium is a vital second messenger for signal transduction in neurons. Calcium plays an important role in almost every part of the human body but in neuronal cytosol, it is of utmost importance. In order to understand the calcium signaling mechanism in a better way a finite element model has been developed to study the flow of calcium in two dimensions with time. This model assumes EBA (Excess Buffering Approximation), incorporating all the important parameters like time, association rate, influx, buffer concentration, diffusion constant etc. Finite element method is used to obtain calcium concentration in two dimensions and numerical integration is used to compute effect of time over 2-D Calcium profile. Comparative study of calcium signaling in two dimensions with time is done with other important physiological parameters. A MATLAB program has been developed for the entire problem and simulated on an x64 machine to compute the numerical results.

Study of Ryodoraku Parameters for Diagnosing Gastric Dysmotility in Functional Dyspepsia (기능성 소화불량증에서 위운동성 장애 진단을 위한 양도락 지표 연구)

  • Kim, So-Yeon;Yoon, Sang-Hyup;Kim, Yoon-Bum;Jung, Sung-Ki
    • The Journal of Internal Korean Medicine
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    • v.29 no.2
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    • pp.401-412
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    • 2008
  • Objectives : The aim of this study was to investigate the characteristics of Ryodoraku and association of Ryodoraku with gastric dysmotility in functional dyspepsia(FD). Methods : Subjects were 154 patients with FD and 18 patients with asthma. We calculated the average Ryodoraku score(RS, ${\mu}A$) and each variation from physiologic range of 12 Ryodoraku points, and investigated the incidence when left and right points were simultaneously below(bilateral deficiency) or above(bilateral excess) physiologic range. Postprandial regularity of normal slow waves, power ratio, and postprandial % of bowel sound were obtained by electrogastrography and enterotachography, and were used as gastric dysmotility index. Results : 1. Bilateral excess of H4, H5, F1, and F4 and bilateral deficiency of H4, H5, and H6 were characteristic in FD compared with asthma patients. 2. Incidence of gastric dysmotility in bilateral deficiency of H4, H5, and H6 was 100%, and was higher than in total FD patients(88.3%). 3. There was a positive correlation between the variation of H6 and % postprandial bowel sound. 4. Deficient tendency of H4, H5, and H6 was more evident when RS was above $40{\mu}A$ in FD. Conclusions : These findings suggest that gastric dysmotility in FD can be diagnosed when a pattern of H4, H5, H6 bilateral deficiency and F1, F4 bilateral excess is shown at the same time. We think this phenomenon is related to low activity of the vagus nerve rather than meridian pathway with result based on positive correlation between variation of H6 and postprandial % of bowel sound.

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Study on the Benefit of Medical Herbal Cosmetics via the pattern identification about fluid-humor of skin in Traditional Korean Medicine (한방 피부 진액변증을 통한 한방화장품의 효능 평가)

  • Kim, Kyoung-Shin;Kim, Byoung-Soo
    • Journal of Haehwa Medicine
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    • v.21 no.1
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    • pp.1-9
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    • 2012
  • Objectives : The aim of this experiment is to find out relationship between the effect of cosmetics and 4 types of pattern identification about fluid-humor, which are based on the general idea of traditional oriental medicine, Qi-Blood and deficiency-excess. Methods : Korean female volunteers in good health (n=25, $23.12{\pm}2.83$) participated in this experiment. Three Korean medical doctors classified them into 4 groups: Blood-deficiency: group A; Blood-excess: group B; Qi-deficiency:group C; Qi-excess:group D). Cosmetics that contains herb extract for Blood deficiency were given to all volunteers and they used the cosmetics for 4 weeks. Volunteers were assessed non-invasively with the skin measuring devices before and after using cosmetics. And we analyzed the correlation of skin physiological parameters with 4 groups. Results : Three doctors diagnosed participants and classified them into 4 groups ; group A(n=8),group B(n=7), group C(n=3), group D(n=5) as highest score. After 4 weeks, facial skin moisture showed no significant difference in comparison between 4 groups. Sebum showed significant increase in Group A and significantly decreased Group B. Measurement of facial skin elasticity tended to increase in Group A, C, D but skin elasticity was decreased significantly in Group B. Conclusions : In case of a group that pattern identification about fluid-humor corresponds to herb extract in cosmetic, skin improving effect was better than the other group that pattern identification oppose to properties of herb in cosmetic. Therefore, from the view of traditional oriental medicine, it is very important to understand user's pattern of identification or physical conditions and properties of herbs in cosmetics on the matter of safety and efficacy.

ON THE NATURE OF SODIUM EXCESS OBJECTS

  • Jeong, Hyunjin;Yi, Sukyoung K.;Kyeong, Jaemann;Sarzi, Marc;Sung, Eon-Chang;Oh, Kyuseok
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.38.2-38.2
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    • 2013
  • Several studies have reported the presence of sodium excess objects having neutral atomic absorption lines at $5895{\AA}$ (NaD) and $8190{\AA}$ that are deeper than expected based on stellar population models that match the stellar continuum. The origin of these lines is therefore hotly debated. van Dokkum & Conroy proposed that low-mass stars (0.3M) are more prevalent in massive early-type galaxies, which may lead to a strong NaI 8190 line strength. It is necessary to test this prediction, however, against other prominent optical line indices such as NaD, Mgb, and Fe5270, which can be measured with a significantly higher signal-to-noise ratio than NaI 8190. We identified a new sample of roughly one thousand NaD excess objects (NEOs; ~8% of galaxies in the sample) based on NaD line strength in the redshift range 0.00${\alpha}$-enhanced" ([${\alpha}/Fe$] ~ 0.3), "metal-rich" ([Z/H] ~ 0.3), and, especially, "Na-enhanced" ([Na/Fe] ~ 0.3).

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A Study on the Consolidation Settlement Due to the Vertical Drain Method by the Implicit Finite Difference Scheme (음적차분해석법을 이용한 연직배수 공법에 의한 압밀침하에 관한 연구)

  • Park, Sung Zae;Jung, Du Hwoe;Jeong, Gyeong Hwan;Lee, Kyeong Joon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.5
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    • pp.1243-1251
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    • 1994
  • The implicit finite difference program was developed to evaluate the relationship between time and consolidation ratio within the zone of vertical drain effective radius. In the evaluation, the excess pore water pressure was considered to dissipate in two directions, namely, vertical and radial flow direction. To calculate subsoil stress increments in the soil due to multi-step embanking, the foundation soil was assumed to be an isotropic and homogeneous elastic medium and the initial excess pore water pressure was estimated by using Skempton's parameters whose condition is plane strain and elastic phase of pore pressure response within the soft ground. Regarding to the settlement estimation, immediate and primary consolidation settlements were calculated. The secondary or delayed consolidation settlement was not considered. Numerically calculated excess pore water pressure and settlements were similar to the measured data in situ. Thus, this method can be used to predict the time-consolidation ratio of each layer treated by vertical drain method.

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Study on the examination and revision about the standard level of the Extreme heat watch warning system for reduction of personal or property injury (인명.재해 피해 저감을 위한 폭염특보기준 검토 및 보완에 관한 연구)

  • Park, Jong-Kil;Jung, Woo-Sik;Song, Jeong-Hui;Kim, Eun-Byul
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.89-92
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    • 2008
  • The extreme heat watch warning system(EHWWS) that Korea Meterological Administration carried out a preliminary from July 1, 2007, considered both daily maximum temperature and daily maximum heat index simultaneously. It was requested revision of the standard level of EHWWS to solve the difficulty of forecasting occurred when we were considering two parameters simultaneously and we did not considering heat index according to areas. For this, we established three type standard, such as type 1 that considered both daily maximum temperature and daily maximum heat index, Under the extreme heat day that daily minimum temperature was more than $25^{\circ}C$, type 2 that considered daily maximum temperature and type 3 that considered only daily maximum heat index and then analyzed whether these 3 types satisfies the excess mortality of the extreme heat warning or not. As a results, type 1 and 2 were more explain away excess mortality each warning step than type 3. type 2 could also apply case of not to consider heat index according to areas and had a merit for extreme heat forecasting easily because the standard was simple. Therefore we think type 2 is more suitable and reasonable standard for Korea extreme heat watch warning system(KEHWWS) than type 1. In addition, we need to develop model that exactly predicts the excess mortality will be take place during the extreme heat warning and construct KEHWWS.

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