• 제목/요약/키워드: Kappa distribution

검색결과 163건 처리시간 0.027초

초음파 검사 영상의 정량적인 측정 연구를 통한 지방간 분석 (Fatty Liver Analysis through Quantitative Measurement Study of Ultrasonography Images)

  • 천혜리;장현철
    • 한국방사선학회논문지
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    • 제16권7호
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    • pp.927-934
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    • 2022
  • 본 연구는 간 초음파 영상을 활용하여 정량적인 측정 분석을 통해 조직 내 감쇠 지수, 조직 내 산란 분포지수 값 분석과 함께 초음파 영상 소견 간 일치도를 알아보고자 하였다. 2022년 8월부터 2022년 10월까지 지방간이 의심되어 간 초음파 검사 처방을 받은 45명의 환자를 대상으로 간 초음파 검사를 시행하였다. 연구결과, 초음파 영상 소견과 조직 내 감쇠 지수 간 일치도 분석 결과 Kappa 값이 0.82(p<0.05)로 두 검사 방법 간 매우 높은 일치도를 보였다. 또한, 초음파 영상 소견과 조직 내 산란 분포 지수 간 일치도 분석 결과에서도 Kappa 값이 0.642(p<0.05)로 두 검사 방법 간 높은 일치도를 보였다. 지방간 예측 시 간 초음파 소견 및 정량적인 초음파 검사 기법인 조직 내 감쇠 지수, 조직 내 산란 분포 지수를 활용한다면 지방간 환자의 진행 정도를 판단할 때 도움이 될 수 있을 것으로 생각된다.

순서를 갖는 척도모수들의 사전정보 하에 k-모집단 와이블분포의 베이지안 모수추정 (Bayesian Estimation of k-Population Weibull Distribution Under Ordered Scale Parameters)

  • 손영숙;김성욱
    • 응용통계연구
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    • 제16권2호
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    • pp.273-282
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    • 2003
  • 순서화된 척도모수들의 사전정보를 가지는 k-모집단 와이블분포의 모수추정을 위한 베이지안방법이 제시된다. 모수추정은 깁스샘플링에 의해서 이루어지며, 특히 깁스샘플러에서 형태모수의 조건부 사후분포는 로그-오목함수이므로 적응기각표집(Adaptive Rejection Sampling: ARS)방법에 의해 모수생성을 하였다. 논의된 모수추정법을 전기 절연유체 고장시간자료에 적용하여 척도모수의 순서화정보를 반영한 경우와 그렇지 않은 경우를 비교하였다.

A Sediment Concentration Distribution Based on a Revised Prandtl's Mixing Theory

  • Jung, Kwan-Sue
    • Korean Journal of Hydrosciences
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    • 제8권
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    • pp.1-17
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    • 1997
  • Prandtl's mixing length theory was modified to obtain a power velocity distribution in which the coefficient and the exponent are variable over a range from : $$ A simple suspended-sediment concentration distribution was developed from the modified velocity distribytion : $ With nominal values of $\beta$=1.0, $\kappa$=0.4 and visual accumulation tube values of the fall velocity, the comparison between the theory and field measurements by the USGS on the Rio Grande is fair. Doubling the value of the exponent results in a good comparison. Further researches are needed for choosing the values of $\beta$, $\kappa$, and fall velocity values, and consideration on the effects of large-scale turbulence and secondary flows are necessary for them. In a pragmatic sense, on any gaging sites the close analysis of very detailed measurements can establish its specific coefficient and exponent.

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Kappa(2) 커버리지 함수를 이용한 ENHPP 소프트웨어 신뢰성장모형에 관한 연구 (The Study for ENHPP Software Reliability Growth Model Based on Kappa(2) Coverage Function)

  • 김희철
    • 한국정보통신학회논문지
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    • 제11권12호
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    • pp.2311-2318
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    • 2007
  • 유한고장수를 가진 비동질적인 포아송 과정에 기초한 모형들에서 잔존 오류 1개당 고장 발생률은 일반적으로 상수, 혹은 단조증가 및 단조 감소 추세를 가지고 있다. 소프트웨어 제품의 정확한 인도시기를 예측하거나 효용성 및 신뢰성을 예측하기 위해서는 소프트웨어 테스팅 과정에서 중요한 요소인 테스트 커버리지를 이용하면 보다 효율적인 테스팅 작업을 할 수 있다. 이런 모형을 ENHPP모형이라고 한다. 본 논문에서는 기존의 소프트웨어 신뢰성 모형인 지수 커버리지 모형과 S-커버리지 모형을 재조명하고 이 분야에 적용될 수 있는 Kappa 분포를 이용한 모형인 Kappa 커버리지 모형을 제안하였다. 고장 간격시간으로 구성된 자료를 이용한 모수추정 방법은 최우추정법과 일반적인 수치해석 방법인 이분법을 사용하여 모수 추정을 실시하고 효율적인 모형 선택은 편차자승합(SSE) 및 콜모고로프 거리를 적용하여 모형들에 대한 효율적인 모형 선택도 시도 하였다. 수치적인 예에서는 실제 고장자료를 통하여 분석하였다 이 자료들에서 기존의 모형과 Kappa 커버리지 모형의 비교를 위하여 산술적 및 라플라스 검정, 편의 검정 등을 이용하였다.

금은화의 NF-${\kappa}B$ 활성 억제를 통한 iNOS 조절이 NC/Nga 생쥐의 아토피 피부염에 미치는 영향 (Lonicera Japonica Inhibits Atopy Dermatitis in NC/Nga Mouse through Regulation of iNOS by NF-${\kappa}B$ Suppression)

  • 안상현;김호현
    • 동의생리병리학회지
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    • 제24권2호
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    • pp.278-283
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    • 2010
  • Inducible nitric oxide synthase (iNOS) are important inflammation enzyme and severe up-nitric oxide (NO) production by this enzyme has been intricate with pathogenesis of atopy dermatitis. The present study was designed in order to determine whether Lonicera japonica could inhibit atopy dermatitis through modulation of iNOS by NF-${\kappa}B$ suppression. We found that IKK mRNA and iNOS mRNA expression in RAW 264.7 macrophages stimulated with lipopolysaccharide dose-dependantly decreased by Lonicera japonica (0.4 - 1.0 mg/$m{\ell}$) and NO production decreased. The distribution of NF-${\kappa}B$ p65 and iNOS positive reacted cell in NC/Nga mice with atopy dermatitis were decreased by Lonicera japonica (45 mg/kg/day) and apoptosis were increased. These data likely indicate that Lonicera japonica may act as inflammatory regulator for atopy dermatitis through iNOS modulation by NF-${\kappa}B$B suppression and may be possible to develop useful agent for chemoprevention of NO intricate inflammatory diseases.

PIV와 CFD에 의한 Ejector내의 유동특성 연구 (A Study on the Flow Characteristics in Ejector by PIV and CFD)

  • 박지만;이행남;박길문;이덕구;설재림
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.723-728
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    • 2003
  • The Ejector is used to get low pressure, and it has been applied to a lot of industry field like the heat engine, the fluid instrument power plant, the food industry, environment industry etc... because there are not any problem even it is mixed with a any kind of liquid, gas, and solid. The flow characteristics in ejector are investigated by PIV and CFD. The experiment using PIV measurement for mixing pipe's flow characteristics acquired velocity distribution, kinetic energy distribution, and whirlpool . (Condition : when mixing pipe's diameter ratio is 1:1.9, and the flux is $Q_{1}=1.136{\imath}/s$, $Q_{2}=1.706{\imath}/s$, $Q_{3}=2.276{\imath}/s$. Based on the PIV and the CFD results, the flow characteristics in ejector are discussed, and it shows the validity of this study.

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3차원 고세장비 공동 주위의 난류유동 및 음향 특성에 관한 수치적 연구 (NUMERICAL ANALYSIS FOR TURBULENT FLOW AND AERO-ACOUSTIC OVER A THREE DIMENSIONAL CAVITY WITH LARGE ASPECT RATIO)

  • 문바울;김재수
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 학술대회
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    • pp.297-301
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    • 2008
  • The flight vehicles have cavities such as wheel wells and bomb bays. The flow around a cavity is characterized as unsteady flow because of the formation and dissipation of vortices due to the interaction between the freestream shear layer and cavity internal flow, the generation of shock and expansion waves. Resonance phenomena can damage the structures around the cavity and negatively affect aerodynamic performance and stability. The flow field is observed to oscillate in the "shear layer mode" with low aspect ratio. In the present study, numerical analysis was performed for cavity flows by the unsteady compressible three dimensional Reynolds-Averaged Navier-Stokes (RANS) equations with Wilcox's $\kappa$-$\omega$ turbulence model. The flow field is observed to oscillate in the shear layer mode" with large aspect ratio. Based on the SPL(Sound Pressure Level) analysis of the pressure variation at the cavity trailing edge, the dominant frequency was analyzed and compared with the results of Rossiter's formul. The aero-acoustic wave analyzed with CPD(Correlation of Pressure Distribution).

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3차원 고세장비 공동 주위의 난류유동 및 음향 특성에 관한 수치적 연구 (NUMERICAL ANALYSIS FOR TURBULENT FLOW AND AERO-ACOUSTIC OVER A THREE DIMENSIONAL CAVITY WITH LARGE ASPECT RATIO)

  • 문바울;김재수
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년 추계학술대회논문집
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    • pp.297-301
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    • 2008
  • The flight vehicles have cavities such as wheel wells and bomb bays. The flow around a cavity is characterized as unsteady flow because of the formation and dissipation of vortices due to the interaction between the freestream shear layer and cavity internal flow, the generation of shock and expansion waves. Resonance phenomena can damage the structures around the cavity and negatively affect aerodynamic performance and stability. The flow field is observed to oscillate in the "shear layer mode" with low aspect ratio. In the present study, numerical analysis was performed for cavity flows by the unsteady compressible three dimensional Reynolds-Averaged Navier-Stokes (RANS) equations with Wilcox's ${\kappa}-{\varepsilon}$ turbulence model. The flow field is observed to oscillate in the "shear layer mode" with large aspect ratio. Based on the SPL(Sound Pressure Level) analysis of the pressure variation at the cavity trailing edge, the dominant frequency was analyzed and compared with the results of Rossiter's formul. The aero-acoustic wave analyzed with CPD(Correlation of Pressure Distribution).

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DSS으로 유발된 생쥐의 대장점막손상에 대한 도체탕(導滯湯)의 효과 (Effects of Doche-tang on Colonic Mucosal Ulcer Induced by DSS in Mice)

  • 이주아;공경환
    • 대한한방내과학회지
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    • 제29권3호
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    • pp.752-764
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    • 2008
  • Objectives : This study was carried out to investigate the effects of Doche-tang on colonic mucosal ulcer induced by dextran sulfate sodium(DSS). Method : The group was divided into three. The normal group consisted of mice that were not inflammation-induced. The control group was composed of untreated colitis elicited mice. The sample group was administered Doche-tang after colitis elicitation. The effects on colonic mucosal ulcers were evaluated by the morphological change of colonic mucosa, the anti-oxidant effect, HSP 70, $NF-{\kappa}B$, COX-1, COX-2 and iNOS. Results : In terms of immunohistochemical findings, the distribution of COX-1 in mice treated with Doche-tang noticeably increased more than that in the control group. The distribution of HSP70, $NF-{\kappa}B$, COX-2, iNOS in mioe treated with Doche-tang decreased more than that in the control group. Regeneration of surface epithelial cell and goblet cell in mucosa was observed by transmission electron microscope. Conclusion : According to the results, Doche-tang is practicable treatment for colonic mucosal ulcer.

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청폐사간탕(淸肺瀉肝湯)이 생쥐의 Lipopolysaccharide 유발 관절염(關節炎)에 미치는 영향(影響) (The Effect of Chungpyesagantang on Lipopolysaccharide induced Arthritis in Mice)

  • 박성식;김주희
    • 사상체질의학회지
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    • 제14권3호
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    • pp.114-131
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    • 2002
  • 1. PURPOSE : The purpose of this study is to investigate the effect of Chungpyesagantang on LPS induced Arthritis in Mice. 2. METHOD : All the BALB/C Mice used in this study were 4wks of age at the start of the experiment. The experimental model of Arthritis was induced by injectection of $300{\mu}g/kg$ LPS in mice knee joint. The experiment was compare daily CS treatment group after Arthritis elicitation with Arthritis elicitated group at day 4, 7, 14 after Arthritis elicitation. 3. RESULTS 1) The hyperplasia of synoviocytes of CS treatment group after Arthritis elicitation is soften than Arthritis elicitated group. 2) The aggregation of collagen fibers CS treatment group after Arthritis elicitation is decreased than Arthritis elicitated group. 3) The distribution of TUNEL positive cells(apoptotic cell) of CS treatment group was remarkably increased than Arthritis elicitated group. 4) The distribution of $TNF-{\alpha}$, $NF-{\kappa}B\;p50$, COX-2 positive cells of CS treatment group after Arthritis elicitation in synovial membrane was decreased than Arthritis elicitated group. 5) The distribution of $IL-2R-{\alpha}$, ICAM-1 positive cells of CS treatment group after Arthritis elicitation in apical surface of synovial membrane was decreased than Arthritis elicitated group. 6) The distribution of $NF-{\kappa}B\;p50$, $IL-2R-{\alpha}$ in common iliac lymph node of CS treatment group after Arthritis elicitation positive cells was decreased than Arthritis elicitated group. 4. CONCLUSION : As a result of these experimental results, it may be concluded that Chungpyesagantang used for treatment of LPS induced Arthritis in Mice. Inflamation activity in CS treatment group after Arthritis elicitation was decreased than Arthritis elicitated group.

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