• Transactions of The Korea Fluid Power Systems Society
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• v.3 no.3
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• pp.8-13
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• 2006

It is very important for the manufacturers to predict the life of hydraulic system components according to the results of life tests. Since it takes too much time to test the hydraulic system components until failure, the no-failure test method is applied for the life test of them. If the shape parameter of Weibull distribution, the number of samples, the confidence level, and the assurance life are given, the no-failure test times of hydraulic system components can be calculated by given equation. Here, the procedures to obtain the no-failure test times of the hydraulic system components such as hydraulic motors and pumps, hydraulic cylinders, hydraulic valves, hydraulic accumulators, hydraulic hoses, and hydraulic filters are described briefly.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.259-278
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• 2002

This study divided straight success, pade success and failure with 7male golfers who have experiences more than 3 years, analyzed kinematic factors of golf swing to suggest scientifically. The conclusions were follows. 1) The wrist angle has significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 2) The body twist angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 3) The shoulder joint rotation angle has no significant difference in success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 4) The left hip joint vertical angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 5) The hip joint rotation angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 6) The trunk angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. 7 )The left knee joint angle has no significant difference in straight success, pade success and failure when swing of every pattern. There is no significant difference in pade success and failure. This study divided golf swing motion of pattern change in straight success, pade success and failure and analyzed the kinematic factors by 3-dimension cinematography to improve performance. In the future, many researchers have to study kinematic analysis to improve performance in every events.

• Geomechanics and Engineering
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• v.17 no.1
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• pp.97-107
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• 2019

Based on the results of Han et al. (2016), in the failure zone ahead of the tunnel face it can be obviously identified that a shear failure band occurs in the lower part and a pressure arch happens at the upper part, which was often neglected in analyzing the face stability of shield tunnel. In order to better describe the collapse failure feature of the tunnel face, a new improved failure mechanism is proposed to evaluate the face stability of shield tunnel excavated in layered soils in the framework of limit analysis by using spatial discretization technique and linear interpolation method in this study. The developed failure mechanism is composed of two parts: i) the rotational failure mechanism denoting the shear failure band and ii) a uniformly distributed force denoting the pressure arch effect. Followed by the comparison between the results of critical face pressures provided by the developed model and those by the existing works, which indicates that the new developed failure mechanism provides comparatively reasonable results.

• Journal of the Korean Society of Safety
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• v.26 no.6
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• pp.104-110
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• 2011

In FMEA, the risk priority number(RPN) is used for risk evaluation on each failure mode. It is obtained by multiplying three components, i.e., severity, occurrence, and detectability of the corresponding failure mode. Each of the three components are usually determined on the basis of the past experience and technical knowledge. But this approach is not strictly objective in evaluating risk of a given failure mode and thus provide somewhat less scientific measure of risk. Assuming a homogeneous Poisson process for occurrence of the failures and causes, we propose a more scientific approach to evaluation of risk in FMEA. To quantify severity of each failure mode, the mission period is taken into consideration for the system. If the system faces no failure during its mission period, there are no losses. If any failure occurs during its mission period, the losses corresponding to the failure mode incurs. A longer remaining mission period is assumed to incur a larger loss. Detectability of each failure mode is then incorporated into the model assuming an exponential probability law for detection time of each failure cause. Based on the proposed model, an illustrative example and numerical analyses are provided.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.279-286
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• 2002

Present all sorts of failure or no failure test methods are done for evaluate structural ability of pavement. It are Plane Plate Test, CBR Test, Benkelman Beam Test, FWD, Dynaflect, etc. but, each method of test not expect compatibility because the result very different by each method of test. Now among pavement's method of evaluation, no failure test gradually use because It quickly and simply obtain pavement's elastic modulus of each layer. But, It accompany expensiveness equipment, and It's degree of trust is lower against expensiveness equipment. Therefore this research practice comparative trustworthy Plane Plate Test, comparative low cost and quick Small FWD Test. And analyzed relation of Plane Plate Test with Small FWD Test.

• The Journal of Korean Academy of Prosthodontics
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• v.30 no.4
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• pp.508-525
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• 1992

The purpose of this study was to evaluate the effect of some resistance form designs on the bond strength of resin-retained prosthesis. Six sub-groups are designed in natural teeth group and resin teeth group . The framework designs in natural teeth group: 1) no groove preparation 2) groove at the center of distal surface 3) groove at the distobuccal line angle 4) 45 degree lateral load with no groove 5) 45 degree lateral load with center groove 6) splint two teeth with no groove. The framework designs in resin teeth group: 1) no groove preparation 2) groove at the center of distal surface 3) groove at the distobuccal line angle 4) metal covered the 1/2 of distal surface 5) metal covered the 1/2 of mesial surface 6) metal extended over the 114 of buccal surface. Specimens were treated electrolytic etching by Oxy-Etch and cemented with Panavia EX. Failure load was measured by Instron. Another 30 specimens were carried out fatigue tests by MTS 810 fatigue testing machine for 5000 cycles at different load level. The following results were obtained from this study. 1. The failure load was significantly increased by resistance forms. 2. The failure load was not increased by increase of total surface area bonded with teeth. The distal surface area played an important role in failure load. 3. In 45 degree lateral load group, the failure load was decreased significantly than that of in vertical load group. 4. Bond failure modes between static test and fatigue test exhibited no differences.

• Journal of Construction Engineering and Project Management
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• v.6 no.4
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• pp.24-34
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• 2016

Disputes seem to be synonymous with large-scale construction projects in Ethiopia. The purpose of this study is to determine the factors responsible for impacting the performance of Ethiopian public construction projects. To this end, 35 success and failure attributes responsible for impacting the performance of the projects were identified and presented to Ethiopian construction professionals in the form of a structured questionnaire, and responses were collected. The factor analysis conducted on the success and failure attributes influencing no-dispute performance separately resulted in six success factors and five failure factors. Further analysis using stepwise multiple regression indicates that owner competence and interaction among project participants have a positive impact on no-dispute performance. However, conflict among project participants has a negative impact on the no-dispute performance of Ethiopian public construction projects. Although Ethiopia-specific, the results reflect construction management problems common to both developed and developing countries. The findings are expected to help researchers and practitioners gain a better understanding of critical success and failure factors and to help them take proactive measures to avoid disputes in public construction projects.

• Journal of Trauma and Injury
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• v.28 no.3
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• pp.104-107
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• 2015

Purpose: Nitric oxide (NO) is a vasodilator and inhaled NO (iNO) is used in acute respiratory distress syndrome (ARDS) to improve alveolocapillary gas exchange. The mechanism to improve oxygenation is likely to redistribute blood flow from unventilated areas to ventilated areas. Though improvement of oxygenation, iNO therapy has not been shown to improve mortality and considered as only rescue therapy in severe hypoxemia. We conducted the study to investigate an efficacy of iNO in trauma patients with severe hypoxemia. Methods: We reviewed the trauma patients who underwent iNO therapy retrospectively from 2010 to 2014. Degree of hypoxemia was represented as $PaO_2/FiO_2$ ratio (PFR) and the severity of patient was represented with sequential organ failure assessment (SOFA) score. Patients were divided into the survivor group and non-survivor group according to the 28-day mortality. Results: A total of 20 patients were enrolled. The mortality of 28-day was 40%. There were no significant differences between survivor and non-survivor group in age, sex, severity of injury, PFR and SOFA score. There was significant difference in initiation time of iNO after injury (p=0.047). Maximum combinations of sensitivity and specificity for timing of iNO therapy were observed using cut-off of 3-day after injury with a sensitivity of 88% and specificity of 75%. Conclusion: Though iNO therapy does not influence the mortality, iNO therapy may decrease the mortality caused by respiratory failure in the early phase of trauma.

• Journal of Korean Institute of Industrial Engineers
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• v.20 no.1
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• pp.39-51
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• 1994

Almost all accelerated life tests assume that no basic failure mechanism changes within the test stresses. But accelerated life test, considering failure mechanism changes, is needed since failure mechanism changes when accelerating beyond the used stress. This paper studies the analysis when the failure mechanism changes within the test stresses. The piecewise linear regression, which the join point of two lines is estimated, is applied In particular, two accelerated life tests, with and without a change in failure mechanism are examined.

• Computers and Concrete
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• v.28 no.6
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• pp.585-603
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• 2021

The validation based on the experimental data demonstrates that the concrete strength under triaxial compression (TC) is overestimated by Lubliner-Oller strength criterion (SC) but underestimated by Lubliner-Lee SC in ABAQUS. Moreover, the discontinuous derivatives of failure criterion exists near the unexpected breakpoints. Both resulted from the piecewise linear meridians of the original Lubliner SC with constants γ. Following the screen for the available failure criteria to determine the model parameter γ of Lubliner SC, Menétrey-Willam SC (MWSC) is considered the most promising option with a reasonable aspect ratio Kc but no other strength values required and only two new model parameters introduced. The failure surface of the new Lubliner SC based on MWSC (Lubliner-MWSC) is smooth and has no breakpoints along the hydrostatic pressure (HP) axis. Finally, predicted results of Lubliner-MWSC are compared with other concrete failure criteria and experimental data. It turns out that the Lubliner-MWSC can represent the concrete failure behavior, and MWSC is the optimal choice to improve the applicability of the concrete damaged plasticity model (CDPM) under TC in ABAQUS.