• 천문학회보
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• 제43권1호
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• pp.56.3-56.3
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• 2018

The present study formulates the theory of spontaneously emitted electromagnetic fluctuations in magnetized plasmas containing particles with an anisotropic suparthermal (bi-Kappa) velocity distribution function. The formalism is general applying for an arbitrary wave vector orientation and wave polarization, and for any wave-frequency range. As specific applications, the high-frequency electromagnetic fluctuations emitted in the upper-hybrid and multiple harmonic electron cyclotron frequency range are evaluated. The fluctuations for low-frequency are also applied, which include the kinetic $Alfv\acute{e}n$, fast magnetosonic/whistler, kinetic slow mode, ion Bernstein cyclotron modes, and higher-order modes. The model predictions are confirmed by a comparison with particle-in-cell simulations. The study describes how energetic particles described by kappa velocity distribution functions influence the spectrum of high and low frequency fluctuations in magnetized plasmas. The new formalism provides quantitative analysis of naturally occurring electromagnetic fluctuations, and contribute to an understanding of the electromagnetic fluctuations observed in space plasmas, where kappa-distributed particles are ubiquitous.

• Communications for Statistical Applications and Methods
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• 제14권2호
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• pp.355-363
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• 2007

In this paper a Bayesian estimation of the two-parameter kappa distribution was discussed under the noninformative prior. The Bayesian estimators are obtained by the Gibbs sampling. The generation of the shape parameter and scale parameter in the Gibbs sampler is implemented using the adaptive rejection Metropolis sampling algorithm of Gilks et al. (1995). A Monte Carlo study showed that the Bayesian estimators proposed outperform other estimators in the sense of mean squared error.

• 한국데이터정보과학회:학술대회논문집
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• 한국데이터정보과학회 2006년도 PROCEEDINGS OF JOINT CONFERENCEOF KDISS AND KDAS
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• pp.163-169
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• 2006

This paper deals with the comparison of parameter estimation methods in a 3-parameter Kappa distribution which is sometimes used in flood frequency analysis. The method of moment estimation(MME), L-moment estimation(L-ME), and maximum likelihood estimation(MLE) are applied to estimate three parameters. The performance of these methods are compared by Monte-carlo simulations. Especially for computing MME and L-ME, ike dimensional nonlinear equations are simplied to one dimensional equation which is calculated by the Newton-Raphson iteration under constraint. Based on the criterion of the mean squared error, the L-ME is recommended to use for small sample size $(n\leq100)$ while MLE is good for large sample size.

• 한국해양공학회지
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• 제15권3호
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• pp.1-8
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• 2001

With uniform heat generation within the wall of the cylinder placed in a cross flow, heat flows by conduction in the circumferential direction due to the asymmetric nature of the fluid flow around the perimeter of the cylinder. The circumferential heat flow affects the wall temperature distribution to such an extent that in some cases significantly different results may be obtained for geometrically similar surfaces. In the present investigation, the effects of circumferential wall heat conduction on local convective heat transfer is investigated for the case of forced convection around horizontal cylinder in cross flow of air. Two-dimensional temperature distribution $T_w$/(${\gamma}$,${\theta}$) is presented through the numerical analysis. The one-dimensional and two-dimensional solutions are in good agreement with experimental results of local heat transfer coefficients.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.915-920
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• 2001

This study was conducted to analysis the distribution of the rectangular stress block for high-strength polymer concrete beam. C-shaped specimens were produced and tested to compute parameters of the rectangular stress block. They were $\kappa_{1}$ = 0.73, $\kappa_{3}$ = 0.94 and $\gamma$= 0.845, respectively. Experimental value of flexural strength of beam was same to be compared with theoretical value. But there is desirable to need many experimental data in order to exact design of polymer concrete structure.

• 한방안이비인후피부과학회지
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• 제20권1호통권32호
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• pp.99-114
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• 2007

Objectives : Atopic dermatitis has a close relationship with damage of skin barrier function. To investigate the effects of Bangpungtongsungsan(BT) extract to the skin damage on mice model after atopic dermatitis elicitation, this study was done through forcing injury to mice's skin. Methods : The BALB/c mice were distributed into three groups: control(CON) group, atopic dermatitis(AD)-elicited group, Bangpungtongsungsan(BT)-treated group. AD-elicited and BT-treated group were caused AD according to the method of Christophers E., Mrowietz and Minehiro. The BT extract was administered for 48 hours to BT-treated group. We observed changes of external dermal formation, eosinophils in vasculature, lipid formation in stratum corneum, distribution of ceramide, distribution of capillary, $I{\kappa}B$ kinase(IKK) and induce nitric oxide synthase(iNOS) mRNA expression. We used the statistical methods of student t-test(p<0.05). Results : After dispensing BT extract into the AD-elicited group, the number of eosinophil as an atopic index in mice noticeably decreased and dermal injury decreased. Also the decrease of hyperplasia, degranulated mast cells, angiogenesis and substance P were shown. The lipid lamellae, lipid protect formation, were repaired and the distribution of ceramide which inhibit protein kinase C(PKC) activation increased, and the PKC caused inhibition of nuclear $factor(NF)-{\kappa}B$ activation. As a result of inhibition of $NF-{\kappa}B$ activation, iNOS production were inhibited and apoptotic cell were increased. Moreover the decrease of IKK and iNOS mRNA expression in BT-treated RAW 264.7 cell were noted. Conclusion : BT mitigated skin damage on mice model after atopic dermatitis elicitation through recovering skin barrier function and inhibiting nuclear $factor(NF)-{\kappa}B$ activation.

• Journal of Nutrition and Health
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• 제42권3호
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• pp.246-255
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• 2009

식품섭취빈도조사지는 식품 목록 종류의 구성방식에 띠라 식품을 기초로 한 조사지와 음식을 기초로 한 두가지 형태로 나누는데, 식품을 기초로 한 조사지는 유지류와 양념류의 영양소를 반영하지 못한다는 문제점이 지적되고 있다. 이 연구는 유지류와 양념류가 대상자 영양소 섭취량과 섭취 분포에 미치는 영향을 파악하고자, 한 농촌지역에서 식생활 요인 평가를 위해 개발하여 사용되고 있는 음식을 기초로 한 식품 빈도조사지를 이용하여, 1) 전체 영양소 섭취량, 2) 유지류를 제외한 영양소 섭취량, 3) 유지류와 양념류를 제외한 영양소 섭취량, 위의 3가지 형태의 영양소 섭취량을 산출하여 영양소 섭취량의 비교와 상관성, 영양소 섭취 분포 일치도를 분석하였다. 그 결과, 총 영양소 섭취량과 유지류를 제외한 영양소 섭취량을 비교하였을 때, 유지류를 제외한 경우, 열량, 식물성지방, 비타민 E 섭취량이 유의하게 낮아졌고, 단순 카파지수는 각각 0.95 (${\kappa}{\omega}$ = 0.98), 0.64 (${\kappa}{\omega}$ = 0.81), 0.59 (${\kappa}{\omega}$ = 0.79) 였다. 유지류와 양념류를 모두 제외한 영양소 섭취량과 총 영양소 섭취량과 비교하면, 유지류와 양념류를 모두 제외하였을 때, 유지류와 양념류에 포함되어 있지 않은 영양소인 동물성 단백질, 동물성 지방, 레티놀을 제외한 대부분의 영양소의 섭취량이 유의하게 낮았고, 그 중 식물성 지방 (K = 0.64, ${\kappa}{\omega}$ = 0.81), 비타민 E (K = 0.59, ${\kappa}{\omega}$ = 0.79), 나트륨 (K = 0.61, ${\kappa}{\omega}$ = 0.80)의 단순 카파지수는 0.8 이하로 다른 영양소에 비해 상대적으로 낮았다. 영양소 섭취 분포 일치도는 열량 보정 후에 조정 전보다 더 낮아졌다. 이상의 연구 결과, 유지류와 양념류를 포함하지 않은 경우 식물성 지방, 비타민 E, 나트륨의 섭취량을 저 평가하였고, 대상자의 영양소 섭취 수준의 분포에 영향을 미쳤다. 따라서, 유지류나 양념류의 조사가 없는 식품기반 식품섭취빈도 조사를 이용하여 질병과의 연관성을 분석할 경우 결과에 대한 해석에 주의해야 한다.

• 한국전산유체공학회지
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• 제18권2호
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• pp.35-40
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• 2013

Natural convection of air with Pr=0.7 between two horizontal plates with small magnitude non-uniform temperature distribution[${\in}{\Delta}Tsin({\kappa}X/H)$, H : gap width, X : horizontal coordinate] in the lower plate is numerically(${\in}=0.01$) investigated. In the conduction-dominated regime with $Ra{\leq}1700$, two upright cells are formed over one wave length($2{\pi}/{\kappa}$). For small wave number, the flow becomes unstable with increase of Rayleigh number, and multicellular convection occurs above a critical Rayleigh number. The flow patterns are classified by the number of eddies over one wave length. When ${\kappa}=1$, a transition of $2{\rightarrow}4{\rightarrow}6$ eddy flow occurs with increase of Rayleigh number, and no hysteresis phenomenon is observed. Dual and triple solutions are found for ${\kappa}=1$, and transitions of $10{\rightarrow}8$, $8{\rightarrow}6$, $6{\rightarrow}4{\rightarrow}2$ eddy flow occur with decrease of Rayleigh number.

• 융합보안논문지
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• 제7권2호
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• pp.1-8
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• 2007

유한고장수를 가진 비동질적인 포아송 과정에 기초한 모형들에서 잔존 결함 1개당 고장 발생률 (강도함수)은 일반적으로 상수, 혹은 단조증가 및 단조 감소 추세를 가지고 있다. 본 논문에서는 기존의 소프트웨어 신뢰성 모형인 Goel-Okumoto 모형 강도함수를 재조명하고 이 분야에 적용 될수 있는 보다 넓은 왜도와 첨도를 가지는 Burr모형 강도 함수 및 의료정보분야 및 여러 분야에서 널리 사용되는 2모수 카파(Kappa(2)) 분포 모형 강도함수를 제안하여 비교하고자 한다. 수치적인 예에서는 고장 간격시간으로 구성된 NTDS(Naval Tactical Data System)자료를 이용하였고 모수추정 방법은 최우추정법과 일반적인 수치해석 방법인 이분법을 사용하여 모수 추정을 실시하였다. 그리고 모형 설정과 선택 판단기준은 편차 자승합을 이용한 적합도 검정이 사용되었다.

• Food Science and Biotechnology
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• 제17권4호
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• pp.794-798
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• 2008

Guar gum and $\kappa$-carrageenan were investigated as a substitutes for phosphate in pork meat processing. Emulsion-type pork sausages were prepared in which 0.5% phosphate was used for the control, and either $\kappa$-carrageenan or guar gum were added at levels of 0.1 or 0.5% for comparison. The hydrocolloid compounds significantly enhanced water holding capacity and cooking loss. However, hardness, cohesiveness, and chewiness were not well-maintained when compared to the control; this was attributable to the altered water distribution as well as enhanced water holding capacity of the sausages by the addition of $\kappa$-carrageenan and guar gum. Furthermore, the phosphate-free sausages had similar storage stability as the phosphate-added sausage. Overall, the results suggest that $\kappa$-carrageenan or guar gum can be used in place of phosphate in conventional processing to successfully prepare phosphate-tree pork sausages.