• 제목/요약/키워드: Consistency of values

검색결과 382건 처리시간 0.028초

부가중합형실리콘인상재의 물리적 특성에 대한 연구 (A Study on the Physical Properties of Addition Silicone Impression Materials)

  • 김수화
    • 치위생과학회지
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    • 제6권4호
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    • pp.231-235
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    • 2006
  • 본 연구는 부가중합형실리콘인상재의 정밀 인상채득에 영향을 미치는 요인, 압축변형률, 탄성회복률, 점주도와 젖음성을 평가하기 위하여 현재 시판되고 있는 4종류의 인상재 Examixfine(GC), Aquasilultra(Dentsply), Extrude(Kerr), Perfect-F(Handae)를 이용하여 실험하였다. 실험 데이터는 SPSSWIN 12.0을 사용하여 분석하였고, 결과는 다음과 같다. 1. 압축변형률은 Extrude가 4.86%로 가장 낮게 나타났고, Examixfine이 6.78%로 가장 크게 나타났다. Examixfine과 Perfect-F 사이에는 유의한 값의 차이가 없었으나, 다른 인상재 그룹에서는 유의성이 있었다. (p < 0.001). 2. Extrude의 탄성회복률이 99.83%로 가장 크게 나타났고, Perfect-F가 96.54%로 가장 낮게 나타났다. Examixfine과 Aquasilultra 간에는 유의성이 없었으나, 다른 인상재그룹간에는 유의한 차이가 있었다(p < 0.001). 3. 점주도의 측정결과에서 Examixfine이 점주도 값이 45.12mm로 가장 높았고, Perfect-F의 경우 40.28 mm로 가장 낮은 점주도 값을 나타내었다. Examixfine과 Aquasilultra, Extrude와 Perfect-F 간에는 유의한 차이가 나타나지 않았다(p > 0.001). 4. 젖음성에서는 Aquasilultra가 $47.85^{\circ}$로 가장 접촉각이 작게 나타나 친수성이 가장 우수하게 나타났고, Perfect-F는 접촉각이 $94.89^{\circ}$로 접촉각이 크게 나타나 소수성으로 나타났다. 인상재 종류별로도 각각 유의성이 존재하였다 (p < 0.001). 5. 접촉각은 압축변형률(p < 0.01), 탄성회복률(p < 0.01), 점주도(p < 0.05)와 상관관계가 있었고, 탄성회복률과 점주도 와는 음의 상관관계를 보였다. 압축변형률은 접촉각, 탄성회복률과 상관관계가 있었고(p < 0.01), 탄성회복률과 음의 상관관계를 나타냈다. 탄성회복률은 접촉각, 압축변형률과 음의 상관관계를 가지고 있었고(p < 0.01), 점주도도 접촉각과 음의 상관관계를 보였다(p < 0.05).

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ON THE GALACTIC SPIRAL PATTERNS: STELLAR AND GASEOUS

  • MARTOS MARCO;YANEZ MIGUEL;HERNANDEZ XAVIER;MORENO EDMUNDO;PICHARDO BARBARA
    • 천문학회지
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    • 제37권4호
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    • pp.199-203
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    • 2004
  • The gas response to a proposed spiral stellar pattern for our Galaxy is presented here as calculated via 2D hydrodynamic calculations utilizing the ZEUS code in the disk plane. The locus is that found by Drimmel (2000) from emission profiles in the K band and at 240 ${\mu}m$. The self-consistency of the stellar spiral pattern was studied in previous work (see Martos et al. 2004). It is a sensitive function of the pattern rotation speed, $\Omega$p, among other parameters which include the mass in the spiral and its pitch angle. Here we further discuss the complex gaseous response found there for plausible values of $\Omega$p in our Galaxy, and argue that its value must be close to $20 km s^{-l}\;kpc^{-1}$ from the strong self-consistency criterion and other recent, independent studies which depend on such parameter. However, other values of $\Omega$p that have been used in the literature are explored to study the gas response to the stellar (K band) 2-armed pattern. For our best fit values, the gaseous response to the 2-armed pattern displayed in the K band is a four-armed pattern with complex features in the interarm regions. This response resembles the optical arms observed in the Milky Way and other galaxies with the smooth underlying two-armed pattern of the old stellar disk populations in our interpretation. The complex gaseous response appears to be related to resonances in stellar orbits. Among them, the 4:1 resonance is paramount for the axisymmetric Galactic model employed, and the set of parameters explored. In the regime seemingly proper to our Galaxy, the spiral forcing appears to be marginally strong in the sense that the 4:1 resonance terminates the stellar pattern, despite its relatively low amplitude. In current work underway, the response for low values of $\Omega$p tends to remove most of the rich structure found for the optimal self-consistent model and the gaseous pattern is ring-like. For higher values than the optimal, more features and a multi-arm structure appears.

Reliability and validity of the patellofemoral disability index as a measure of functional performance and subjective pain in subjects with patellofemoral pain syndrome

  • Alshaharani, Mastour Saeed;Lohman, Everett Bernell;Bahjri, Khaled;Harp, Travis;Alameri, Mansoor;Daher, Noha S.
    • Physical Therapy Rehabilitation Science
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    • 제7권2호
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    • pp.61-66
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    • 2018
  • Objective: Patellofemoral pain syndrome (PFPS) is a condition that is characterized by patellar discomfort or pain that is aggravated during certain activities such as ascending/descending stairs. The Patellofemoral Disability Index (PDI) was developed to assess the effect of pain on functional activities in individuals with PFPS. The objectives of the current study were to determine the internal consistency, test-retest reliability, and validity of this index. Design: Cross-sectional study. Methods: Forty-one subjects who had PFPS with a mean age of $28.8{\pm}5.0years$ and a mean body mass index of $25.6{\pm}4.7kg/m^2$ participated in the study. All subjects were concurrently enrolled in a clinical trial for which they were instructed to complete hamstring-resistance exercises for 4 weeks. Over the course of the intervention, they completed both the PDI and the Oswestry Disability Index (ODI) at baseline after two weeks, and after four weeks. Pearson correlation coefficient was used to assess the criterion validity. Cronbach's ${\alpha}$ was used to examine the internal consistency. Intraclass correlation coefficients with 95% confidence interval were computed to examine test-retest reliability. Results: Subjects' responses within both the PDI and the ODI yielded Pearson correlation coefficient values that were positive and highly significant (range, 0.73-0.97; p<0.001). There was a high level of internal consistency (Cronbach's ${\alpha}{\geq}0.8$), with the exception of stair climbing (Cronbach's ${\alpha}=0.65$). Intraclass correlation ranged from 0.87 to 0.92, indicating high levels of test-retest reliability. Conclusions: The PDI is a valid, reliable, and feasible method of assessing pain and functional ability in patients with PFPS.

Application of Molecular Simulation Techniques to Estimation of Gas Permeability in Zeolite Membranes

  • Takaba, Hiromitsu;Yamamoto, Atsushi;Nakao, Shin-Ichi
    • 한국막학회:학술대회논문집
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    • 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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    • pp.33-38
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    • 2004
  • Molecular modeling of gas permeation through zeolite membranes with/without intercrystalline region was carried out. Molecular dynamics (MD) and Monte Carlo (MC) simulations were performed to estimate the diffusion coefficient and adsorption parameters respectively, and our proposed combined method of molecular simulation techniques with a permeation theory (CMP) was used to estimate gas permeability. The calculated permeability of gases (Ar, He, Ne, $N_2$, $0_2$, $CH_4$) at 301 K for the single crystal membrane model was about one order of magnitude larger than the experiential values, although the dependence on the molecular weight of the permeating species agreed with experiments. On the other hand, the estimated permeability using the diffusivity and adsorption parameters of the intercrystalline region model was in good agreement with the experiments. The consistency between experiments and the estimated values means the importance of considering the intercrystalline region and the validity of CMP method to predict the performance of zeolite membranes.

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쌀보리 전분 호화액의 리올로지 특성 (Rheological Properties of Naked Barley Starches)

  • 박양균;노일환;김관;김성곤;이신영
    • 한국식품과학회지
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    • 제18권4호
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    • pp.278-282
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    • 1986
  • 쌀보리 품종인 송학과 영산 전분의 가열 호화액의 리올로지 특성을 비교하였다. $90^{\circ}C$에서 30분간 호화시킨 3,5,7 및 9% 전분 호화액은 모두 의가소성의 거동을 나타냈고, 점조도지수 K 및 항복을력 $\tau_y$ 값은 송학이 영산보다 컸으며 더 높은 농도의존성을 나타내었다. 전분농도의 증가에 따라 송학과 영산 모두 점조도지수 K값이 지수함수적으로 증가하였으며 5%근처에서는 기울기가 서로 다른 2개의 직선관계를 나타냈다. 아레니우스식에 의해 구한 활성화에너지는 7% 송학과 영산 전분용액에서 각각 4.098 및 3.71kcal/mole 이었다.

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한국어판 간호사 직무 스트레스 측정도구의 타당도와 신뢰도 분석 (Validity and Reliability of the Korean Version of the Expanded Nursing Stress Scale)

  • 김경미;남경아;이은희;정금희
    • 간호행정학회지
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    • 제21권5호
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    • pp.542-551
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    • 2015
  • Purpose: This study was done to evaluate validity and reliability of the Korean version of the expanded nursing stress scale (ENSS). Methods: Forward-backward translation of ENSS from English to Korean was conducted. The translated instrument was pilot-tested and administrated to 285 nurses who worked in five general hospitals in Korea. Internal consistency reliability was assessed using Cronbach's ${\alpha}$ and composite reliability. Validity was evaluated through construct validity with confirmatory factor analysis, convergent and discriminant validity. Results: The Korean version of ENSS showed a reliable internal consistency with Cronbach's ${\alpha}$ .95 and composite reliability .99. Model fit indexes for 46 items were validated by confirmatory factor analysis(goodness of fit index .82, Tucker-Lewis index .92, root mean square error of approximation .04), indicating suitable construct validity. Factor loading of the 48 items (.47~.88) and average variance extracted out of nine factors (.52~.71.) indicated satisfactory convergent validity. Some values of square of the correlation coefficient between factors (.12~.89) were higher than average variance extracted values of each factor (.52~.71) so that it partly satisfied discriminant validity. Conclusion: Findings show that the Korean version ENSS has good reliability and suitable validity; therefore, can be used to assess and identify Korean nurses' job stress.

An Evidence Retraction Scheme on Evidence Dependency Network

  • Lee, Gye Sung
    • International journal of advanced smart convergence
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    • 제8권1호
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    • pp.133-140
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    • 2019
  • In this paper, we present an algorithm for adjusting degree of belief for consistency on the evidence dependency network where various sets of evidence support different sets of hypotheses. It is common for experts to assign higher degree of belief to a hypothesis when there is more evidence over the hypothesis. Human expert without knowledge of uncertainty handling may not be able to cope with how evidence is combined to produce the anticipated belief value. Belief in a hypothesis changes as a series of evidence is known to be true. In non-monotonic reasoning environments, the belief retraction method is needed to clearly deal with uncertain situations. We create evidence dependency network from rules and apply the evidence retraction algorithm to refine belief values on the hypothesis set. We also introduce negative belief values to reflect the reverse effect of evidence combination.

Effect of different voxel sizes on the accuracy of CBCT measurements of trabecular bone microstructure: A comparative micro-CT study

  • Tayman, Mahmure Ayse;Kamburoglu, Kivanc;Ocak, Mert;Ozen, Dogukan
    • Imaging Science in Dentistry
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    • 제52권2호
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    • pp.171-179
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    • 2022
  • Purpose: The aim of this study was to assess the accuracy of cone-beam computed tomographic (CBCT) images obtained using different voxel sizes in measuring trabecular bone microstructure in comparison to micro-CT. Materials and Methods: Twelve human skull bones containing posterior-mandibular alveolar bone regions were analyzed. CBCT images were obtained at voxel sizes of 0.075mm(high: HI) and 0.2mm(standard: Std), while microCT imaging used voxel sizes of 0.06 mm (HI) and 0.12 mm (Std). Analyses were performed using CTAn software with the standardized automatic global threshold method. Intraclass correlation coefficients were used to evaluate the consistency and agreement of paired measurements for bone volume (BV), percent bone volume (BV/TV), bone surface (BS), trabecular thickness (TbTh), trabecular separation (TbSp), trabecular number (TbN), trabecular pattern factor(TbPf), and structure model index (SMI). Results: When compared to micro-CT, CBCT images had higher BV, BV/TV, and TbTh values, while micro-CT images had lower BS, TbSp, TbN, TbPf, and SMI values (P<0.05). The BV, BV/BT, TbTh, and TbSp variables were higher with Std voxels, whereas the BS, TbPf, and SMI variables were higher with HI voxels for both imaging methods. For each imaging modality and voxel size evaluated, BV, BS, and TbTh were significantly different(P<0.05). TbN, TbPf, and SMI showed statistically significant differences between imaging methods(P<0.05). The consistency and absolute agreement between micro-CT and CBCT were excellent for all variables. Conclusion: This study demonstrated the potential of high-resolution CBCT imaging for quantitative bone morphometry assessment.

물리치료 전문직관의 핵심가치에 대한 요인분석 (Factor Analysis of Core Values of Professionalism in Physical Therapy)

  • 박은영;김원호;이관우
    • 한국산학기술학회논문지
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    • 제13권12호
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    • pp.5901-5908
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    • 2012
  • 이 연구는 물리치료사 470명을 대상으로 미국물리치료사협회에서 개발한 물리치료 전문직관을 번안하여 이 측정도구의 구성타당도와 신뢰도를 알아보기 위해 실시되었다. 확인적 요인분석을 통해 구성타당도를 알아보았고, 문항내적합치도를 통해 신뢰도를 분석하였다. 번안된 물리치료 전문직관 측정도구는 모형이 적합한 것으로 나타났고(p<.05), 7개요인(역할유연성, 이타주의, 동정/배려, 우수성, 도덕성, 전문가적 책무, 사회적 책무)으로 확인되었다. 구성요인의 표준화계수는 도덕성(${\beta}$=.93), 전문가적 책무(${\beta}$=.92), 동정/배려(${\beta}$=.86) 순으로 높았다. 성별에 따른 전문직관의 차이는 없었으나(p>.05) 임상경력에 따라서는 유의한 차이가 있었다(p<.05). 또한 전문직관은 문항내적합치도가 매우 높았다(Cronbach ${\alpha}$=.80~.96). 번안된 물리치료 전문직관은 구성타당도와 신뢰도가 있는 것으로 나타났기 때문에, 물리치료 전문직관을 측정하는 도구로 유용할 것으로 여겨진다.

비정형성 등속운동 객체의 움직임 추정을 위한 블록기반 움직임 평활화 (Block-based Motion Vector Smoothing for Nonrigid Moving Objects)

  • 손영욱;강문기
    • 대한전자공학회논문지SP
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    • 제44권6호
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    • pp.47-53
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    • 2007
  • 블록 기반 프레임 레이트 변환 (frame-rate conversion) 또는 필름 떨림 보상 (film judder compensation)을 수행하기 위해서는 참 움직임 벡터(true motion vector)를 찾아야 한다. 이를 위해서 현재 블록의 공간적 및 시간적 상관성을 최대로 하여 시각적으로 덜 부자연스럽게 느끼도록 하는 방법들이 연구되었다. 그러나 기존의 블록단위 절대값 차이의 합 (SAD)만으로는 비정형성 객체의 움직임 에러를 추정할 수 없었다. 본 논문에서는 비정형성 객체가 등속운동을 하는 경우 재귀적으로 기존의 움직임을 유지하도록 하는 방법을 제안하였다. 현재 블록의 등속움직임 추정값을 재귀평균으로 구하였으며 현재 블록 벡터의 신뢰도를 계산하여 원래의 움직임 벡터와 재귀평균 움직임 벡터중에서 가중치를 두도록 하였다. 실험결과 비정형성 등속운동 객체의 움직임을 블록기반으로 추정함을 확인할 수 있었다.