• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.29-36
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• 2014

Finite failure NHPP software reliability models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, proposes the Gompertz distribution reliability model, which made out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on mean square error (MSE) and coefficient of determination$(R^2)$, for the sake of efficient model, was employed. Analysis of failure using real data set for the sake of proposing fixed shape parameter of the Gompertz distribution was employed. This analysis of failure data compared with the Gompertz distribution model of shape parameter. In order to insurance for the reliability of data, Laplace trend test was employed. In this study, the proposed Gompertz model is more efficient in terms of reliability in this area. Thus, Gompertz model can also be used as an alternative model. From this paper, software developers have to consider the growth model by prior knowledge of the software to identify failure modes which can was helped.

• Herbal Formula Science
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• v.23 no.1
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• pp.121-131
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• 2015

Objectives : This study was conducted to investigate the membrane potential to apply Doksam-tang to a human heart failure model. Methods : The human heart model was built by Luo et al. CellML model, Priebe et al. CellML model, and a human heart mesh file. Doksam-tang gives channel the half maximal inhibitory concentration(IC ₅₀ ), half maximal effective concentration(EC ₅₀ ) values and compounds concentrations. These data load into the laptop with Ubuntu OS, and build the library with the data. Results : While results of the study with the heart failure model shows abnormal membrane potential from the normal heart model, the study with applying Doksam-tang to heart failure model shows restoring membrane potential that is similar to normal heart model. Conclusions : These results of the testings suggest that a conception of novel technique to investigate the effects of Korean herbal medicine.

• Interaction and multiscale mechanics
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• v.4 no.3
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• pp.187-206
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• 2011

Accurate estimations of pre-failure deformations and post-failure responses of geostructures require that the simulation tool possesses at least three main ingredients: 1) a constitutive model that is able to describe the macroscopic stress-strain-strength behavior of soils subjected to complex stress/strain paths over a wide range of confining pressures and densities, 2) an embedded length scale that accounts for the intricate physical phenomena that occur at the grain size scale in the soil, and 3) a computational platform that allows the analysis to be carried out beyond the development of an initially "contained" failure zone in the soil. In this paper, a two-scale micropolar plasticity model will be used to incorporate all these ingredients. The model is implemented in a finite element platform that is based on the mechanics of micropolar continua. Appropriate finite elements are developed to couple displacement, micro-rotations, and pore-water pressure in form of $u_n-{\phi}_m$ and $u_n-p_m-{\phi}_m$ (n > m) elements for analysis of dry and saturated soils. Performance of the model is assessed in a biaxial compression test on a slightly heterogeneous specimen of sand. The role of micropolar component of the model on capturing the post-failure response of the soil is demonstrated.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.309-314
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• 1999

In this paper, an application of finite element procedure fur tunnel failure analysis has been studied. The numerical model is applied to the simulation of a series of plane strain laboratory tests on the small scale model of a shallow tunnel. By comparing experimental and numerical results some conclusions are drawn on the effectiveness of the numerical approach. The findings from these numerical experiments show relative differences in the pattern of failure behaviour for shallow tunnels.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.393-396
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• 1999

This paper presents a truss model for RC columns subjected to axial load and lateral load. The presented model is based on a stress field for the flexural-shear failure of short columns, which represent shear failure and bond splitting failure. Using this model, failure strength and related deformation of RC columns are investigated. Particular emphasis is placed on models capable of representing the interaction between deformation and shear strength.

• Journal of the Korean Ceramic Society
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• v.26 no.1
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• pp.116-122
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• 1989

MOR test and concentric ring test were performed to evaluate the failure probability of sin/hip Si3N4 under uniaxial and biaxial stress state, respectively. Their failure probabilities were analized with KARA program based on Weibull PIA model and Batdorf model with 5 criteria, and they were compared with experiments. PIA model is in best accordance with experiments in higher fracture strength regions, especially for Pf 0.3. But in lower fracture strength region, none of the models predicts the failure probabilities appropriately.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.391-396
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• 2003

The concrete corbels consist of various failure mechanisms such as the yielding of the tension reinforcement, the crushing or splitting from compression concrete struts, and localized bearing or shearing failure under the loading plate. However, predicting those failure mechanisms is very difficult. In this study, the ACI 318-02, the softened strut-tie model approach, and the nonlinear strut-tie model approach are applied to ultimate strength analysis of normal strength concrete corbels tested to failure. From the result of the analysis, an effective analysis and design method of normal strength concrete corbels is suggested.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.2
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• pp.1-13
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• 2002

In this paper, we compares the business failure prediction accuracy among Linear Programming Discriminant Analysis(LPDA) model, Multivariate Discriminant Analysis (MDA) model and logit analysis model. The Data for 417 companies analyzed were gathered from KIS-FAS Published by Korea Information Service in 1999. The result of comparison for four time horizons shows that LPDA Is advantageous in prediction accuracy over the other two models when over all tilt ratio and business failure accuracy are considered simultaneously.

• Journal of Korean Institute of Industrial Engineers
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• v.39 no.2
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• pp.143-148
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• 2013

In FMEA, occurrence and detectability are not related to only failure modes itself but also their causes. It is assumed that any failure occurs after at least one cause corresponding to failure occurs in advance. Occurrence of the failure mode is described by occurrence time of its cause and elapsed time to the actual failure. Under the periodic monitoring plan, the monitoring interval is another factor to determine the detectability and occurrence of each failure mode. When a failure cause occurs, the failure does not occur if the cause is identified and remedied before it actually occurs. Under this situation, we construct an economic model for prioritizing failure modes. The loss function is based on the unfulfilled mission period. We also provide an optimal monitoring plan with an illustrative example.

• Geomechanics and Engineering
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• v.21 no.4
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• pp.349-356
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• 2020

Rock brittleness, which is closely related to the failure modes, plays a significant role in the design and construction of many rock engineering applications. However, the brittle-ductile failure transition is mostly ignored by the current statistical damage constitutive model, which may misestimate the failure strength and failure behaviours of intact rock. In this study, a new statistical damage model considering rock brittleness is proposed for brittle to ductile behaviour of rocks using brittleness index (BI). Firstly, the statistical constitutive damage model is reviewed and a new statistical damage model considering failure mode transition is developed by introducing rock brittleness parameter-BI. Then the corresponding damage distribution parameters, shape parameter m and scale parameter F₀, are expressed in terms of BI. The shape parameter m has a positive relationship with BI while the scale parameter F₀ depends on both BI and ε_e. Finally, the robustness and correctness of the proposed damage model is validated using a set of experimental data with various confining pressure.