• Title/Summary/Keyword: 2-Parameter Criterion

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3-D Concrete Model Using Non-associated Flow Rule in Dilatant-Softening Region of Multi-axial Stress State (3차원 솔리드요소 및 비상관 소성흐름 법칙을 이용한 콘크리트의 응력해석)

  • Seong, Dae Jeong;Choi, Jung Ho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.12 no.2
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    • pp.193-200
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    • 2008
  • Cohesive and frictional materials such as concrete and soil are pressure dependent. In general, failure criterion for such materials inclined with respect to positive hydrostatic axis in Haigh-Westergaard stress space. Consequently, inelastic volumetric strain always positive with associated flow rule. In this study, to overcome this shortcoming, non-associated flow rule which controls volumetric component of plastic flow is adopted. Numerical analysis based on a constitutive model using nonuniform hardening plasticity with five parameter failure criterion and non-associated flow rule has conducted to predict concrete behavior under multi-axial stress state and verified with experimental result.

Evaluation of the Humpty Dumpty Falls Scale: An Analysis of Electronic Medical Records (소아 낙상위험 측정도구 (Humpty Dumpty Falls Scale) 평가: 전자의무기록을 이용하여)

  • Cho, Yun Hee;Kim, Young Ju
    • Journal of Korean Clinical Nursing Research
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    • v.25 no.2
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    • pp.142-150
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    • 2019
  • Purpose: The aim of this study was to evaluate the efficiency of the Humpty Dumpty Falls Scale as one of the falls risk assessment tools, and also to evaluate risk factors as predictors of falls in pediatric patient populations. Methods: In a retrospective, case-control design with data from the electronic medical records of 13 pediatric patients who fell and 1,941 who did not fall before matching and 429 who did not fall after matching by gender, age, diagnosis, and length of stay. Results: All the variables showed no significant differences after matching. At the cutoff score of 13, sensitivity, specificity, negative and positive predictive values were 92.3%, 37.1%, 99.9%, and 0.01%, respectively. The area under the Receiver Operating Characteristics was 0.597. The results from the logistic regression showed that the pediatric inpatient population who had higher risk scores was significantly associated with falls. The odds ratios ranged from 1.31 to 4.71 with 90% confidence interval. Conclusion: The saturation impairments criterion as one of the diagnostic parameter was negatively associated with falls, but the relative risk score was higher than the other criteria. Therefore, it seems that the diagnostic parameter seems to be required to verify results through large sample studies.

The Parameter Identification of Tidal Model on The Boundary-Fitted Coordinates (Boundary-Fitted 좌표계로 변환한 2차원조석모형의 매개변수 동정)

  • 김경수;이재형
    • Water for future
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    • v.23 no.3
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    • pp.319-328
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    • 1990
  • The Parameter Identification of 2-demensional estuarine model was carried out using new output ADI-FDM numerical semi-implicit schem transformed in boundary fitted(BF) - coordinate. The hydrodynamic equations which is coupled with the transport equations were used as basic equations in the model. Thompson's equations were used to transform governing equations into rectangular plane equations and his elliptic grid generation scheme was used to generate curvilinear grid system. in BF - coordinates. The parameters to be identified are friction coefficient and disperse coefficient embedded in the governing equations. The numerical output scheme is tidally averaged salinity model in BF - coordinates. The algorithm to optimize norm of error between observations and calculations is the influence coefficinet algorithm associated with least square criterion. The lumped model is conssidered in identification. This paper was concetrated on checking whether the new output scheme might be useful to identify parameters in estuarine salinity model or not. The proposed method was tested through experimental application with hypothetical simple model. The result of the test shows that the proposed method can be used for parameter identification in estuarine model.

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A Numerical Investigation on End Bearing Capacity of Single Pile Installed in Fractured Rock Mass (절리암반에 설치된 단말뚝기초의 선단지지력에 관한 수치해석 연구)

  • Kim, Tae-Jung;Yoo, Chung-Sik
    • Journal of the Korean Geotechnical Society
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    • v.29 no.1
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    • pp.61-70
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    • 2013
  • This paper presents the results of a two-dimensional finite element analysis of end bearing capacity of single pile installed in fractured rock mass. A number of cases were analyzed using Hoek-Brown criterion that can consider the condition of rock joints. Considering a wide range of joint conditions in which the pile is embedded into the rock, GSI was set as a main parameter. And the effects of pile diameter, unconfined compressive strength of rock and Hoek-Brown constant $m_0$ were considered. Based on parameter study, end bearing load factor graphs were suggested.

Focusing Geometry Dependence of Single Pass Raman Shifer (단인 통과 라만레이저의 집속 조건에 따른 출력 특성)

  • 고춘수
    • Korean Journal of Optics and Photonics
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    • v.4 no.4
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    • pp.434-441
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    • 1993
  • Focusing geometry dependence of output Stokes energy in single pass methane Raman shifter is investigated. The experimental result shows that the threshold energy decreases as confocal parameter increases. This result can be explained by gain suppression caused by Stokes - anti-Stokes coupling. In this paper, we give simple analysis for the focusing geometry dependence of Stokes - anti-Stokes coupling and present the criterion of confocal parameter to reduce the gain suppression. Focusing geometry dependence of stimulated Brillouin scattering is measured and the result is in good agreement with theoretical prediction.

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Heave Metal Toxicity Test in Moina macrocopa with Glucose-6-phosphate Dehydrogenase Activity (Glucose-6-phosphate dehydrogenase를 이용한 Moina macrocopa의 중금속 독성 검정)

  • Park Yong-seok;Lee Sang-Goo;Lee Seung-Jin;Moon Sung-Kyung;Choi Eun-Joo;Rhie Ki-tae
    • Environmental Analysis Health and Toxicology
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    • v.18 no.4
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    • pp.305-310
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    • 2003
  • A rapid, inexpensive enzymatic method is proposed for indirect water quality testing in terms of heavy metal toxicity. The activity of glucose-6-phosphate dehydrogenase was applied for heavy metal toxicity test as an effective criterion in water quality. The toxicity of Pb (lead) and Cd (cadmium) for water flea, Moina macrocopa, were evaluated for 2-8 days with variables of mobilization ability. And the reproduction impairment of Moina macrocopa were investigated as the parameter of chronic toxicity test for Pb and Cd. As a result, the EC$_{50}$ for immobilization of Moina macrocopa were Pb and Cd were 1.6749 and 0.4683, respectively. The values of reproductive impairment to Moina macrocopa for Pb and Cd were 9.5938 and 8.3264 in EC$_{50}$ A significant alteration of G6PDH (Glucose-6-phosphate dehydrogenase) activity of Moina macrocopa was observed when Cd and Pb were treated in media. The results obtained indicate that G6PDH activity of Moina macrocopa can be used as an indicative parameter in aquatic toxicity tests for heavy metals.als.

Noninformative Priors for the Difference of Two Quantiles in Exponential Models

  • Kang, Sang-Gil;Kim, Dal-Ho;Lee, Woo-Dong
    • Communications for Statistical Applications and Methods
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    • v.14 no.2
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    • pp.431-442
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    • 2007
  • In this paper, we develop the noninformative priors when the parameter of interest is the difference between quantiles of two exponential distributions. We want to develop the first and second order probability matching priors. But we prove that the second order probability matching prior does not exist. It turns out that Jeffreys' prior does not satisfy the first order matching criterion. The Bayesian credible intervals based on the first order probability matching prior meet the frequentist target coverage probabilities much better than the frequentist intervals of Jeffreys' prior. Some simulation and real example will be given.

An Adaptive Image Quality Assessment Algorithm

  • Sankar, Ravi;Ivkovic, Goran
    • International journal of advanced smart convergence
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    • v.1 no.1
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    • pp.6-13
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    • 2012
  • An improved algorithm for image quality assessment is presented. First a simple model of human visual system, consisting of a nonlinear function and a 2-D filter, processes the input images. This filter has one user-defined parameter, whose value depends on the reference image. This way the algorithm can adapt to different scenarios. In the next step the average value of locally computed correlation coefficients between the two processed images is found. This criterion is closely related to the way in which human observer assesses image quality. Finally, image quality measure is computed as the average value of locally computed correlation coefficients, adjusted by the average correlation coefficient between the reference and error images. By this approach the proposed measure differentiates between the random and signal dependant distortions, which have different effects on human observer. Performance of the proposed quality measure is illustrated by examples involving images with different types of degradation.

Estimate on related to Chip Set and the other Various Parameter in Electronic Plastic Package (반도체 패키지의 칩셋과 다른 설계변수와의 연관성 평가)

  • Kwon, Yong-Su
    • Journal of the Korean Society of Industry Convergence
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    • v.2 no.2
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    • pp.131-137
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    • 1999
  • Package crack caused by the soldering process in the surface mounting plastic package is evaluated by applying the energy release rate criterion. The package crack formation depend on various parameters such as chip set, chip size, package thickness, package width, material properties and the moisture content etc. The effects of chip set and the other parameters were estimated during the analysis of package cracks which were located in the edge of the upper interface of the chip and the lower interlace of the die pad. From the results, it could be obtained that the more significant parameters to effect the chip set are chip width.

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Comparisons of Various Properties for Zero Suppression Algorithms (Zero Suppression 알고리듬들의 여러 가치 특성 비교)

  • 이훈재;박영호
    • Journal of Korea Society of Industrial Information Systems
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    • v.6 no.1
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    • pp.7-14
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    • 2001
  • Among zero-suppression (ZS) algorithms proposed for synchronous stream cipher system, ZS-1 has the difficulty on the implementation of stream cipher system, ZS-2 has a weakness of channel error propagation, and ZS-3 has the complexity on the hardware. Because each algorithm must be chosen carefully to the application system, in this paper, we propose a criterion of the system adapted from the simulated results on the parameter changed.

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