• International Journal of Naval Architecture and Ocean Engineering
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• v.4 no.3
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• pp.313-321
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• 2012

Vibration analysis of a thin-walled structure can be performed with a consistent mass matrix determined by the shape functions of all degrees of freedom (d.o.f.) used for construction of conventional stiffness matrix, or with a lumped mass matrix. In similar way stability of a structure can be analysed with consistent geometric stiffness matrix or geometric stiffness matrix with lumped buckling load, related only to the rotational d.o.f. Recently, the simplified mass matrix is constructed employing shape functions of in-plane displacements for plate deflection. In this paper the same approach is used for construction of simplified geometric stiffness matrix. Beam element, and triangular and rectangular plate element are considered. Application of the new geometric stiffness is illustrated in the case of simply supported beam and square plate. The same problems are solved with consistent and lumped geometric stiffness matrix, and the obtained results are compared with the analytical solution. Also, a combination of simplified and lumped geometric stiffness matrix is analysed in order to increase accuracy of stability analysis.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.05a
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• pp.113-116
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• 1995

Simplified approach has been adopted for the prediction of the thermal behavior of CANDU reactor core during power transients. Based on the assumption that the ratio of mass flow rate for each core channel does not vary during the transient, quasy-steady state analysis technique is applied with predicted core inlet boundary conditions(total mass flow rate and specific enthalpy). For restricted transient case, the presented method shows functionally reasonable estimation of core thermal behavior which could be implemented in the fast running reactor simulation program.

• Journal of Advanced Navigation Technology
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• v.14 no.3
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• pp.446-451
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• 2010

This paper addressed an another scheme of distortion estimation method based on simplified inverse quantization in H.264/AVC. The distortion is calculated by the difference of coefficient between quantized transform coefficients and that of inverse. In general, these process included such transforms as discrete cosine transform(DCT), quantization, inverse quantization(IQ), and Inverse DCT(IDCT). In proposed approach, IQ as well as IDCT process are skipped because of replacing a couple of approximated formulas. Some simulation have been conducted and it showed that the PSNR was almost the same, and reduced the rate-distortion optimization(RDO) mode decision time of 8~15% in comparison with conventional method.

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1835-1838
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• 2013

Polypyrrole-Gold (PPy/Au) segment nanowires are prepared using anodized aluminum oxide (AAO) templates and assembled into a curved superstructure. Since the shape of the obtained superstructures can be designed to be capsule-like with inner space for containing materials, and their openings and closures can be controlled with external stimuli, these structures can be useful for a large variety of applications. Inner space of capsule-like superstructures is an important factor for their applications, and the volume of the inner space can be assessed using the generalized equation suggested by J. K. Lim (Bull. Korean Chem. Soc. 33, 2699 (2012)). In this paper, we introduce a new approach to obtain correct and simplified equation without redundant assumption which was used to induce the previous equations, and recalculate the volume of the inner space in the capsule-like superstructure using a new equation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1472-1479
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• 2002

In order to improve automotive fuel economy, vehicle weight should be reduced. Achieving significant weight reductions will normally require reducing the panel thickness or using alternative materials such as aluminum alloy sheet. These changes will affect the dent resistance of the panel. In this study, the correlation between panel size, curvature, thickness, material properties and dent resistance is investigated. A parametric approach is adopted, utilizing a "design software" tool incorporating empirical equations to predict denting and panel stiffness for simplified panels. The most effective period to optimize an automotive body panel is early in its development. The developed design program can be used to minimize panel thickness or compare different materials, while maintaining adequate panel performance.

• Textile Coloration and Finishing
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• v.18 no.3 s.88
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• pp.16-22
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• 2006

Process contract has received considerable attention in silk degumming processes because of its critical role in quality assurance. In degumming, process exhibits shrinkage of high twisted yarn and lot-varying behavior, thus increasing the difficulties of reduction by conventional means. This necessitates the application of a package that adapts to changing degumming process, and a new approach involving package degumming is proposed. The gains of this process are prevent of shrinkage by package winding, which is simplified by reduced soft-winding or re-twisting process. The approach is expected to achieve high quality results in conventional process due to its feature of demage by tension and rubbing. Therefore package degumming has many merits such as reduce of pilling and shrinkage, production expenses saving by process contract are expected of the simplified degumming process.

• Structural Engineering and Mechanics
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• v.61 no.3
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• pp.389-396
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• 2017

Concrete pavements are subjected to traffic and environmental loadings. Repetitive type of such loading cause fatigue distress which leads to failure by forming cracks in pavement. Fatigue life of concrete pavement is calculated from the stress ratio (i.e. the ratio of applied flexural stress to the flexural strength of concrete). For the correct estimation of fatigue life, it is necessary to determine the maximum flexural tensile stress developed for practical loading conditions. Portland cement association PCA (1984) and Indian road congress IRC 58 (2015) has given charts and tables to determine maximum edge stresses for particular loading and subgrade conditions. It is difficult to determine maximum stresses for intermediate loading and subgrade conditions. The main purpose of this study is to simplify the analysis of rigid pavement without compromising the accuracy. Equations proposed for determination of maximum flexural tensile stress of pavement are verified by finite element analysis.

• 한국항공운항학회:학술대회논문집
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• 2015.11a
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• pp.25-28
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• 2015

Aircraft conceptual design usually uses low to medium fidelity analysis to determine the basic configuration of an aircraft. Optimum solution is bounded by at least one of the constraints in most cases. This solution has risk to fail at later stage when analyzed with more sophisticated analysis tools. This research uses pre-constructed database to estimate the analysis prediction errors associated with simplified analysis methods. A possibility based design optimization framework is developed to utilize the newly proposed piecewise-linear fuzzy membership functions that compensate the discrepancies caused by simplified analysis. The proposed approach for aircraft design produces the optimum aircraft configurations that are less likely to fall into infeasible region when analyzed using higher fidelity analysis at later design stages.

• Earthquakes and Structures
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• v.14 no.6
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• pp.551-565
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• 2018

Experimental testing is considered the most realistic approach to obtain a detailed representation of the nonlinear behaviour of masonry-infilled reinforced concrete (RC) structures. Among other applications, these tests can be used to calibrate the properties of numerical models such as simplified macro-models (e.g., strut-type models) representing the masonry infill behaviour. Since the significant cost of experimental tests limits their widespread use, alternative approaches need to be established to obtain adequate data to validate the referred simplified models. The proposed paper introduces a detailed finite element modelling strategy that can be used as an alternative to experimental tests to represent the behaviour of masonry-infilled RC frames under earthquake loading. Several examples of RC infilled frames with different infill configurations and properties subjected to cyclic loading are analysed using the proposed modelling approach. The comparison between numerical and experimental results shows that the numerical models capture the overall nonlinear behaviour of the physical specimens with adequate accuracy, predicting their monotonic stiffness, strength and several failure mechanisms.

• Fibers and Polymers
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• v.1 no.1
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• pp.55-58
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• 2000

We present a new approach to bale laydown grouping, which improves the laydown to laydown uniformities, compared to conventional approaches. In this approach, we use a frequency-relative picking method based on an HVI quality index for cotton bale selection and laydown formation. We demonstrate the effectiveness of this approach by computer simulation on real HVI data of 1500 cotton bales. Simulation results show that the proposed method significantly outperforms random picking.