• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.353-360
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• 2002

The objective of this study is to develop a technique that analyzes the global behavior of frame structures with local cracks. The technique is based on frame analysis and uses the stiffness matrix of cracked frame element. An algorithm proposed here analyzes a frame structure with local transverseedge cracks, considering the effects of crack length and location. Stress intensity factors are employed to calculate additional local compliance due to the cracks based on linear elastic fracture mechanics theory, and then this local compliance is utilized to derive the stiffness matrix of the cracked frame element. In order to verify the accuracy and reliability of the proposed approach, numerical results are compared with those of Finite Element Method for the cracked frame element, and the effects of single crack on the behavior of truss structure are also examined.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.112-119
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• 2004

This paper develops a computer model of a cabover type large truck for estimating the effects of the mounted method of frame on handling performance. The computer model considers two mounted methods of frame; flange mounted and web mounted. Frame is modeled by finite elements using MSC/NASTRAN in order to consider the flexibility of frame. The reliability of the developed computer model is verified by comparing the actual vehicle test results with the simulation results. The actual vehicle test is performed in a double lane change course, and lateral acceleration, yaw rate, and roll angle are measured. To estimate the effects of the mounted method of frame on handling performance, simulations are performed with the flange mounted and web mounted frame. Simulation results show that the web mounted frame＇s variations of roll angle, lateral acceleration, and yaw rate are larger than the flange mounted frame＇s variations, especially in the high test velocity and the second part of the double lane course. Also, simulation results show that the web mounted frame＇s tendencies of roll angle, lateral acceleration, and yaw rate advance the flange mounted frame＇s tendencies, especially in the high test velocity and the second part of the double lane course.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 1999.12a
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• pp.63-85
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• 1999

$\cdot$New CSP using Lead Frame and solder ball techniques. $\cdot$EMC needs high filler content, low CTE and high flexural modulus. $\cdot$Solder Joint Reliability improved by anchor leads. .Uniform inner lead shape would be better at capacitance values. $\cdot$Low Assembly cost CSP.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.89-94
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• 2003

Rolling stock structures such as bogie frame and car body play an important role for the support of vehicle leading. In general, more than 25 years' durability is needed for them. A lot of study has been carried out for the prediction of the fatigue life of the bogie frame and car body in experimental and theoretical domains. One of the new methods is a probabilistic fatigue lift evaluation. The objective of this paper is to estimate the fatigue lift of the bogie frame of an electric car, which was developed by the Korea Railroad Research Institute (KRRI). We used two approaches. In the first approach probabilistic distribution of S-N curve and limit state function of the equivalent stress of the measured stress spectra are used. In the second approach, limit state function is also used. And load spectra measured by strain gauges are approximated by the two-parameter Weibull distribution. Other probabilistic variables are represented by log-normal and normal distributions. Finally, reliability index and structural integrity of the bogie frame are estimated.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.2
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• pp.41-45
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• 2015

RtMLF (Routable Molded Lead Frame) based on molded substrate has been developed to maximize advantages of both leadframe product which has high thermal and electrical performance and laminate product which accommodates more I/O count and keeps fan-in/fan-out design flexibility. Due to its structural features, RtMLF provided excellent thermal and electrical performance which was confirmed with simulation. The RtMLF samples were manufactured and its reliability analysis was done to evaluate the opportunities of the production and application.

• Journal of the Korea Concrete Institute
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• v.12 no.6
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• pp.119-126
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• 2000

Reinforced concrete structural walls are widely known to provide an efficient lateral load resistance and drift control. However, many reported researches on them are mostly limited to the RC structural walls reinforced according to seismic details. When the pushover analysis technique is used for the prediction of inelastic behavior of frame-wall structures for the seismic evaluation of existing buildings having non-seismic details, the reliability of this analysis method should be checked by the test results. The objective of this study is to verify the correlation between the experimental and analytical responses of a high-rise reinforced concrete frame-wall structure having non-seismic details by using DRAIN-2DX program[11] and the test results performed previously[1]. It is concluded that the behavior of the frame-wall model is mainly affected by the fixed-end rotation(uplift at base) and bending deformation of the wall and that the analysis with the LINKS model[10] in DRAIN-2DX describes them with good reliability.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.09a
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• pp.227-234
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• 2001

The responses of a 1:5 scale 3-story masonry-infilled RC frame which was designed only for gravity loads were simulated by using a nonlinear analysis program, DRAIN-2DX The objective of this study is to verify the correlation between the experimental and analytical responses of masonry-infilled RC frame. It is concluded from this comparison that the strength and stillness of the whole structure can be predicted with quite high reliability using compressive strut (compression link element, Type 09) while some local behavior cannot be described reasonably.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.439-444
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• 2003

The response of a 1:5 scale 3-story masonry-infilled RC frame which was designed only for gravity loads were simulated by using a nonlinear analysis program, RUAUMOKO 2D. The objective of this study is to understand behavior of masonry-infilled panel and to verify the correlation between the experimental and analytical responses of a masonry-infilled RC frame. It is concluded from this comparison that the strength, stiffness and local behavior of the structure can be predicted with some reliability using this macro-model.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.03a
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• pp.313-320
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• 2003

The responses of a 1:5 scale 3-story masonry-infilled RC frame which was designed only for gravity loads were simulated by using a nonlinear analysis program, DRAIN-2DX. The objective of this study is to verify the correlation between the experimental and analytical responses of a masonry-infilled RC frame. It is concluded from this comparison that the strength and stiffness of the whole structure can be predicted with quite high reliability using compressive strut (compression link element, Type 09).

• International Journal of Reliability and Applications
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• v.13 no.2
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• pp.71-80
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• 2012

This paper introduces a new approach for evaluating reliability of a complex system in terms of distributional parameters where analytical determination of reliability is intractable. The concept of discrete approximation, reported in the literature so far, fails to meet the latter requirement in terms of distributional parameters. The current work aims at offering a bound based approach where reliability planners not only get a clear idea about the extent of error but also can manipulate in terms of distributional parameters. This reliability approximation has been under taken under the Weibull frame work which is the most widely used model for reliability analysis. Numerical study has been carried out to examine the strength of our proposed reliability approximation via closeness between the two reliability bounds. This approach will be very useful during the early stages of product design as the distributional parameters can be adjusted.