• Title/Summary/Keyword: Sigma S

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Tensile Properties of Plate Attached Open Cell Aluminium Foams (판이 부착된 개포형 발포 알루미늄의 인장특성)

  • Kang, Bok-Hyun;Bu, Sung-Duk;Kim, Ki-Young
    • Journal of Korea Foundry Society
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    • v.27 no.2
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    • pp.83-87
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    • 2007
  • Aluminum plates of the same materials as the foam were attached by the casting process inserting the foam as a core to investigate the tensile property of open cell foams. Tensile properties of the open cell 6063 aluminum alloy foam of $10{\sim}30$ PPI were measured before and after heat treatment. Densities of test specimens were between 0.14 and $0.29g/cm^3$. Tensile strength of the 6063 aluminum foam after heat treatment showed little change. C values were in the range of $0.41{\sim}0.87$ for as cast foams and $0.11{\sim}0.27$ for T6 heat treated foams in the eq. of ${\sigma}^* _{pl}/{\sigma}_{ys}=C({\rho}/{\rho}_s)^{1.5}$, and increased with increase in the cell size.

Real-time Face Detection using AdaBoost and Motion Detection (AdaBoost와 모션 검출을 이용한 실시간 얼굴 검출)

  • Ryu, Dong-Gyun;Lee, Jae-Heung
    • Proceedings of the Korea Information Processing Society Conference
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    • 2017.04a
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    • pp.1020-1023
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    • 2017
  • Viola와 Jones가 제안한 AdaBoost(Adaptive Boosting) 알고리즘은 기존의 물체 검출기에 비해 속도와 정확도 면에서 우수하여 실시간 물체 검출기로써 좋은 성능을 보인다. 하지만 여전히 많은 계산량 때문에 성능이 낮은 임베디드 환경에서는 실시간 검출에 대한 아쉬움이 있다. 본 논문에서는 계산량을 줄이기 위해 모션 검출을 통해 배경 영역을 제거하고 얼굴 영역을 추정한다. 제거된 배경 영역은 AdaBoost 알고리즘의 검출 과정에서 제외되며 추정된 얼굴 영역에 대해서만 검출을 하게 된다. 모션검출은 ${\Sigma}-{\Delta}$(Sigma-Delta) 배경 추정에 기반한 알고리즘을 사용한다.

On certain maximal operators being $A_1$ weights

  • Suh, Choon-Serk
    • Communications of the Korean Mathematical Society
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    • v.10 no.4
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    • pp.881-887
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    • 1995
  • Let f be a measurable function on the unit ball B in $C^n$, then we define a maximal function $M_p(f), 1 \leq p < \infty$, by $$ M_p(f)(\zeta ) = \sup_{\delta > 0}(\frac{1}{\sigma(\beta(\zeta, \delta))} \int_{T(\beta(\zeta, \delta))} $\mid$f(z)$\mid$^p \frac{d\nu(z)}{(1-$\mid$z$\mid$^n})^{1/p} $$ where $\sigma$ denotes the surface area measure on S, the boundary of B, and $T(\beta(\zeta, \delta))$ denotes the tent over the ball $\beta(\zeta, \delta)$. We prove that the maximal operator $M_p$ belongs to the Muckenhoupt class $A_1$.

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Comparison of MIVQUE Estimators Using EQDGs for the One-way Random Model with Unbalanced Data (불균형 일원랜덤효과모형에서 EQDGs를 이용한 MIVQUE 추정량 비교)

  • Jung, Byoung-Cheol
    • The Korean Journal of Applied Statistics
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    • v.18 no.2
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    • pp.411-420
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    • 2005
  • In this study, the MIVQUE estimators of variance components for the one-way random model with unbalanced data are investigated. In order to compare the efficiency of MIVQUE estimators obtained by using three priori estimates, the Empirical Quantile Dispersion Graphs (EQDGs) are used. From the results of Monte-Carlo study, the MIVQUE estimator using ${\sigma}^2_{\alpha}\;=\;0\;and\;{\sigma}^2_{varraho}=1$ as the priori estimate performs well relative to other estimators.

Development of C-TPM Model for Small and Medium Size Enterprise (중소기업에 적합한 C-TPM 모델 개발)

  • Choi, Moo-Ho;Ree, Sang-Bok
    • Proceedings of the Korean Society for Quality Management Conference
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    • 2010.04a
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    • pp.390-401
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    • 2010
  • In this paper, we wish to develop suitable TPM Model (C-TPM) in Korea's medium and small enterprises. TPM technique was informed well and there are a lot of success instances but there was problem that is not fitness in medium and small enterprises. In this study, we propose C-TPM model in medium and small enterprises by examining TPM success example variously. This model construction constructed based on medium and small enterprises field supervision and experience, and verification of model is assignment late.

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A Case Study W Company on the productivity innovation by changing U-Line into the TPS (TPS를 이용한 자동차 Press 부품 가공 W사 사례연구)

  • Han, Myoung-Soo;Ree, Sang-Bok
    • Proceedings of the Korean Society for Quality Management Conference
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    • 2010.04a
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    • pp.67-73
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    • 2010
  • This study began the study by instructing enterprises to change Batch Production into U-Line. This study suggested TPS U-Line building model process and applied it to some of their product line. By connecting concerned process elements into continuous operations. Outside orders were also switched to inside operations and executed in continuous operations, thereby about 100Km of transit distance became zero Km, Production lead Time was incredibly reduced. After all, 90% of Production Lead Time, 50% of handling fault, 3/4 of workers decreased and Productivity per Person enhanced which involves improving Batch Production into Continuous Production and applies it to the real world, so that small and medium enterprises can consult this study if the company is willing to make an improvement to their product line.

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Sublimation Pressure and Standard Enthalpy of Bismuth Triiodide by Torsion-Effusion Method (Torsion-Effusion 법에 의한 Bismuth Triiodide의 승화압과 표준 엔탈피)

  • 김준학
    • Journal of the Korean Ceramic Society
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    • v.28 no.2
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    • pp.109-118
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    • 1991
  • Steady-state sublimation vapour pressures of anhydrous bismuth triiodide have been measured by the torsion-effusion method from 488.8 to 570.5 K and equilibrium sublimation pressures were obtained from the steady-state data. The standard sublimation enthalpy changes derived by both second(modified sigma function) and third(average enthalpy method) law methods were 159.316${\pm}$0.055, 137.67${\pm}$1.43 kJ$.$mol-1 respectively. The standard sublmation entropy change derived by modified sigma function was 232.88${\pm}$0.10 J$.$K-1$.$mol-1. The reliable standard sublimation enthalpy change based on a correlation of {{{{ { TRIANGLE }`_{cr } ^{g } }} H{{{{ { 0} atop {m } }}(298.15K) and {{{{ { TRIANGLE }`_{cr } ^{g } }} S{{{{ { 0} atop {m } }}(298.15K), a recommended p(T) equation has been obtained for BiI3(cr) ; lg(p/Pa)=-(C$.$K/T)+5.071lg(T/K)-2.838${\times}$10-3(T/K)-7.758${\times}$103(K/T)2+1.4519 where C={{{{{ { TRIANGLE }`_{cr } ^{g } }} H{{{{ { 0} atop {m } }}(298.15K)/0.019146 kJ$.$mol-1}-456.27.

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Substituent Effects on the Basicities of Azoxy-Compounds (Azoxy系化合物의 鹽基性에 미치는 置換基效果)

  • Chi Sun Hahn;Hak Soo Lyu
    • Journal of the Korean Chemical Society
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    • v.7 no.1
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    • pp.69-73
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    • 1963
  • The basicities of 16 substituted azoxybenzenes have been measured by U.V. spectrophotometric method. The effects of substituents on the basicities are discussed in terms of Hammett's equation. The reaction constants, ${\rho}^X_Y$ and ${\rho}^Y_X$ , in a modified equation, log $K_{XY}/K_{\infty}={\sigma}_X{\rho}^Y_X+{\sigma}_Y{\rho}^X_Y$, are $2.46{\pm}0.12$ and $2.25{\pm}0.26$ respectively. The validity of the equation is analysed by a statistical method, and the structure of the conjugate acid of the substituted azoxybenzenes is proposed.

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Improvement of Hospital Sickroom Thermal Environment through Reestablishment of Fiducial Temperature (종합병원 온도기준 재정립을 통한 병실 열환경 개선에 관한 연구)

  • Lee, Kang-Bok;Kim, Young-Il;Chung, Kwang-Seop
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.573-578
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    • 2009
  • Survey shows that temperature accounts for 90.6% of dissatisfaction in general hospital environment. In order to improve this situation, operation and thermal data of S hospital collected in 2006 are analyzed. The objective of this study is to find optimum fiducial temperature that minimizes occupants' complaints using 6 sigma method.

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A study on the stress Distributions and magnetic properties during Hot-pressing according to Strain Rate of Nd-Fe-B-Cu Alloys (Nd-Fe-B-Cu합금의 변형속도에 따른 열간압축시 응력분포와 자기적 특성에 관한 연구)

  • Park, J.D.;Jeung, W.Y.;Kwak, C.S.
    • Journal of the Korean Society for Precision Engineering
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    • v.10 no.2
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    • pp.146-153
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    • 1993
  • Thd specimens were melited in high frequency induction furnace. The samples for measurements were prepared by machining cylinder of 9.5mm diameter and 15mm height. These samples were then hot-pressed according to strain rate ( .epsilon. ). These samples were decanned and cut out, and subsequently heat treated at 1000 .deg. C for 4hours. These were investigated for the change of microstructure, domain pattern, X-ray diffraction and magnetic properties. The stress distributions in the specimens during compressing process were calculated by a finite element method program(SPID). The calculated stresses were effective stress( .sigma. $_{eff}$), compressive direction stress( .sigma. $_{z}$), and shear stress( .tau. $_{rz}$ ). These stresses were compared with the experimental data.a.a.

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