• Tribology and Lubricants
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• v.23 no.4
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• pp.156-161
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• 2007

The friction test using disk-on-pad type was carried out and regression analysis with friction parameters was applied fur wear loss presumption of motorcycle break disk. The wear loss has an effect on the frictional factor such as applied load, sliding speed, and number of ventilated disk hole. However, it is difficult to know the mutual relation of these factors on wear loss of motorcycle break disk. From this study, the result was shown that the regression analysis equation containing 4 elements were constructed and this equation had a trust of 95% in wear loss presumption of motorcycle break disk. It is possible to apply for another automobile parts.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.7 s.112
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• pp.729-738
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• 2006

Knowledge of acoustic transmission loss of acoustic window material has a great importance for the sonar performance in ship. The purpose of this study was to investigate the measurement and analysis method for the acoustic transmission loss of the acoustic window materials for sonar dome. The measurement and analysis were carried out in water with GRP material. Transmission losses were calculated based on integrated direct and transmitted signals. The experimental setup enabled to vary the angle of incidence. Thus the transmission loss data could be expressed as the function of frequency and angle of rotation. In this paper, diffraction effect of incident angle, size of specimen with test material, transmission analysis method and multiple waves as incident acoustic signal were discussed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.11
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• pp.1591-1602
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• 1998

Simple spanwise distribution models of deviation angle and pressure loss coefficient due to the tip leakage flow are formulated for use in association with the streamline curvature method as a flow analysis. Combining these new models with the previous deviation and loss models due to secondary flow, a robust streamline curvature method is established for flow analysis of single-stage, subsonic axial turbines with wide ranges of turning angle, aspect ratio and blading type. At the exit from rotor rows, the flow variables are mixed radially according to a spanwise transport equation. The proposed streamline curvature method is tested against a forced vortex type turbine as well as a free vortex type one. The results show that the spanwise variations of flow angle, axial velocity and loss coefficients at rotor exit are predicted with good accuracy, being comparable to a steady three-dimensional Navier-Stokes analysis. This simple and fast flow analysis is found to be very useful for the turbine design at the initial design phase.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.1183-1189
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• 2006

Knowledge of acoustic transmission loss of acoustic window material has a great Importance for the sonar performance in ship. The purpose of This study was to investigate the measurement and analysis method for me acoustic transmission loss of the acoustic window materials for sonar dome. The measurement and analysis were carried out in water with GRP material. Transmission losses were calculated based on integrated direct and transmitted signals. The experimental setup enabled to vary the angle of incidence. Thus the transmission loss data could be expressed as the function of frequency and angle of rotation. In this paper, diffraction effect of incident angle, size of specimen with test material, transmission analysis method and multiple waves as incident acoustic signal wet-e discussed

• Earthquakes and Structures
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• v.14 no.5
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• pp.437-447
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• 2018

Computational cost is one of the major obstacles for detailed risk analysis of structures. This paper puts forward a methodology for efficient probabilistic seismic loss assessment of structures using the Endurance Time (ET) analysis and the first-order reliability method (FORM). The ET analysis efficiently yields the structural responses for a continuous range of intensities through a single response-history analysis. Taking advantage of this property of ET, FORM is employed to estimate the annual rate of exceedance for the loss components. The proposed approach is an amalgamation of two analysis approaches, ET and FORM, that significantly lower the computational costs. This makes it possible to evaluate the seismic risk of complex systems. The probability distribution of losses due to the structural and non-structural damage as well as injuries and fatalities of a prototype structure are estimated using the proposed methodology. This methodology is an alternative to the prevalent risk analysis framework of the total probability theorem. Hence, the risk estimates of the proposed approach are compared with those from the total probability theorem as a benchmark. The results indicate a satisfactory agreement between the two methods while a significantly lower computational demand for the proposed approach.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.1
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• pp.1-8
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• 2001

Performance of a rectangular fin is investigated by a three dimensional analytical method. Heat loss and the temperature obtained from the three dimensional analysis are compared with those calculated from a two dimensional analysis. Fin effectiveness, fin resistance and fin efficiency for the rectangular fin are presented as a function of non-dimensional fin length and fin width. The results are obtained in the following : (1) heat loss calculated from the two dimensional analysis is the same as that obtained from the three dimensional analysis with adiabatic boundary condition in z-direction, (2) heat loss obtained from the two dimensional analysis approaches the value for the three dimensional analysis as the non-dimensional fin width becomes large, (3) fin effectiveness increases as non-dimensional fin length increases and non-dimensional fin width decreases, and vice versa for fin efficiency.

• Journal of Information Technology Applications and Management
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• v.16 no.3
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• pp.59-71
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• 2009

Hazard analysis identifies probability to hazard occurrence and its potential impact on business processes operated in organizations. This paper illustrates a quantitative approach of hazard analysis of information systems by measuring the degree of hazard to information systems using probabilistic risk analysis and activity based costing technique. Specifically the research model projects probability of occurrence by PRA and economic loss by ABC under each identified hazard. To verify the model, each computerized subsystem which is called a business process and hazards occurred on information systems are gathered through one private organization. The loss impact of a hazard occurrence is produced by multiplying probability by the economic loss.

• Animal Bioscience
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• v.35 no.4
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• pp.624-630
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• 2022

Objective: The aim of this study was to investigate the expression level of filaggrin-2 (FLG2) in correlation with drip loss. Methods: The muscle samples were randomly taken from a local meat supplier. Samples were taken from Longissimus lumborum muscles to evaluate the drip loss (n = 100). Five muscles per group (low and high drip loss) were selected to evaluate FLG2 mRNA and protein expression levels. Results: mRNA of FLG2 gene was not significantly different in pigs with different levels of drip loss (p>0.05). Statistical analysis revealed that FLG2 protein expression levels were significantly different between the drip loss groups. Western blot revealed that the high drip loss group had higher FLG2 protein expression level than the low drip loss group (p<0.001). Moreover, immunohistochemistry revealed the high signal intensity was on the muscle cell membrane and cytoplasm. Conclusion: FLG2 protein might play roles in drip loss of pork and will provide the basis for information to improving meat quality traits in pigs.

• Journal of the Korean Society for Railway
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• v.16 no.1
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• pp.20-25
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• 2013

The frame elements of modern high speed trains are typically fabricated with extruded aluminum panels. However, the sound transmission loss (STL) of extruded aluminum panels is less satisfactory than flat panels with the same surface density. This study proposes a method for prediction of the sound transmission loss of extruded aluminum panels using finite element analysis. The panel is modeled by finite element analysis, and the STL is calculated using a measure of Sommerfeld radiation at the specimen surface, boundary conditions, and the internal loss factor of the material. In order to verify the validity of the predicted value, intensity transmission loss was measured on the aluminum specimen according to ASTM E2249-02. The proposed method of analysis will be utilized to predict the sound insulation performance of extruded aluminum panels for railway vehicles in the design stage, and to establish measures for their improvement.

• Journal of KSNVE
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• v.10 no.3
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• pp.423-429
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• 2000

This paper investigates the use of boundary element method(BEM) to analyze the insertion loss of a noise barrier. To begin with the validity of the BEm for the analysis of noise barrier insertion loss in checked by both Lam's theoretical method and the measurements in the anechoic chamber for the scale-down models. Through simulation it is shown that using 2D BEM model is sufficient to the analysis for the barrier with large ratio of length to height. By using 2D BEM model the insertion loses are predicted for the real noise barriers in several cases which are the case that they are built parallel on both roadsides the one that there are multiple sound sources and the one that there is a gap between a concrete structure and a barrier plate.