• Journal of Advanced Marine Engineering and Technology
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• v.31 no.4
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• pp.363-369
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• 2007

Probably the most significant heat transfer in the cryogenic liquid hydrogen storage tank from the atmosphere may occur through its support system. In this paper the efficient support system for the cryogenic storage vessel was newly developed and analysed. The support system was composed of a spherical ball as a supporter to reduce the contact area. which is located between two supporting SUS tubes inserted SUS and PTFE blocks. Numerical analyses for temperature distribution, and the thermal stress and strain of the support system were performed by the commercial codes FLUENT and ANSYS. The heat transfer rate of the supporter was evaluated by the thermal boundary potential method which can consider the variation of thermal conductivity with temperature. The results showed that the heat transfer rate through the developed supporter compared with the common SUS tube supporter was significantly reduced. The thermal stress and strain were obtained well below the limited values. It was found that the developed supporter can be one of the most efficient support systems for cryogenic liquid storage vessel.

• Journal of Environmental Impact Assessment
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• v.22 no.5
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• pp.439-454
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• 2013

UN-REDD (United Nations programme on Reducing Emissions from Deforestation and forest Degradation) is currently being emerged as one of important mechanism to reduce carbon dioxide in relation to the deforestation. Although administrative boundary has already gained world-wide recognition as a typical method of monitoring unit in the process of GHG (Greenhouse Gas) reduction project, this approach did not provide a realistic evidence in the carbon sequestering monitoring in terms of UN-REDD; the meaningful comparison of land use patterns among watershed boundaries, interpretation for distribution trends of carbon density, calculation of opportunity cost, leakage management, etc. This research proposes a comparative evaluation framework in a more objective and quantitative way for carbon sequestering monitoring between administrative and watershed boundary approaches. Mt. Geumgang of North Korea was selected as a survey objective and an exhaustive and realistic comparison of carbon sequestration between the two approaches was conducted, based on change detection using TM satellite images. It was possible for drainage boundary approach to identify more detailed area-wide patterns of carbon distribution than traditional administrative one, such as estimations of state and trends, including historical trends, of land use / land cover and carbon density in the Mt. Geumgang. The distinctive changing trends in terms of carbon sequestration were specifically identified over the watershed boundary from 4.0% to 34.8% while less than 1% difference was observed in the administrative boundaries, which were resulting in almost 21-22%. It is anticipated that this research output could be used as a valuable reference to support more scientific and objective decision-making in introducing watershed boundary as carbon sequestering monitoring unit.

• The Journal of Information Systems
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• v.26 no.2
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• pp.43-62
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• 2017

Purpose This study provided empirical support for the model that explain the formation of privacy concerns in the perspective of Information Boundary Theory. This study investigated an integrated model suggesting that privacy concerns are formed by the individual's disposition to value privacy, privacy awareness, awareness of privacy policy, and government legislation. The Information Boundary Theory suggests that the boundaries of information space dependends on the individual's personal characteristics and environmental factors of e-commerce. When receiving a request for personal information from e-commerce websites, an individual assesses the risk depending on the risk-control assessment, the perception of intrusion give rise to privacy concerns. Design/methodology/approach This study empirically tested the hypotheses with the data collected in a survey that included the items measuring the constructs in the model. The survey was aimed at university students. and a causal modeling statistical technique(PLS) is used for data analysis in this research. Findings The results of the survey indicated significant relationships among environmental factors of e-commerce websites, individual's personal privacy characteristics and privacy concerns. Both individual's awareness of institutional privacy assurance on e-commerce and the privacy characteristics affect the risk-control assessment towards information disclosure, which becomes an essential components of privacy concerns.

• Interaction and multiscale mechanics
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• v.2 no.2
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• pp.129-151
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• 2009

This paper presents a meshfree procedure using a convex generalized meshfree (GMF) approximation for the large deformation analysis of particle-reinforced rubber compounds on microscopic level. The convex GMF approximation possesses the weak-Kronecker-delta property that guarantees the continuity of displacement across the material interface in the rubber compounds. The convex approximation also ensures the positive mass in the discrete system and is less sensitive to the meshfree nodal support size and integration order effects. In this study, the convex approximation is generated in the GMF method by choosing the positive and monotonic increasing basis function. In order to impose the periodic boundary condition in the unit cell method for the microscopic analysis, a singular kernel is introduced on the periodic boundary nodes in the construction of GMF approximation. The periodic boundary condition is solved by the transformation method in both explicit and implicit analyses. To simulate the interface de-bonding phenomena in the rubber compound, the cohesive interface element method is employed in corporation with meshfree method in this study. Several numerical examples are presented to demonstrate the effectiveness of the proposed numerical procedure in the large deformation analysis.

• 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.690-696
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• 2006

Thickness of damping layer in sandwich plate needs to be optimized in order to make modal loss factor of the sandwich plate maximum. Since previous studies were interested in noise reductions over high frequency range, the modal properties were derived based on simply supported boundaries. This conventional formula is approximately applicable to other boundary conditions over high frequency range only. The purpose of this study is to propose a method to determine optimum damping layer thickness of sandwich plate for maximum modal damping in low frequency range when the boundary condition is not a simple support. The conventional RKU equation based on simply supported boundary is modified to reflect other boundary conditions and the modified RKU equation is subsequently applied to determine the optimum damping layer thickness for arbitrary conditions. In order to reflect frequency-dependent characteristics of elastic modulus of the damping layer, an iteration method is proposed in determining the modal properties. Test results on sandwich plates for optimum damping layer thickness are compared with predictions by the proposed method and conventional method.

• 한국전산유체공학회:학술대회논문집
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• 2000.05a
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• pp.113-119
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• 2000

Two-dimensional steady flow of two immiscible, compressible fluids are considered when the temperature of each layer is constant. Both upper and lower fluids are bounded by two horizontal rigid boundaries with symmetric obstruction of compact support at the tourer boundary. By using asymptotic method, we derive the forced K-dV equation governing interfacial wave. Various solutions and numerical results are presented.

• Structural Engineering and Mechanics
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• v.62 no.2
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• pp.247-258
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• 2017

Beam-like structures such as bridge, high building and tower, pipes, flexible connecting rods and some robotic manipulators are often excited by support motions. These structures are important in machines and structures. So, this study proposes an analytic method to accurately predict the dynamic behaviors of the structures during support motions or an earthquake. Using Timoshenko beam theory which is valid even for non-slender beams and for high-frequency responses, the analytic responses of fixed-fixed beams subjected to a real seismic motions at supports are illustrated to show the principled approach to the proposed method. The responses of a slender beam obtained by using Timoshenko beam theory are compared with the solutions based on Euler-Bernoulli beam theory to validate the correctness of the proposed method. The dynamic analysis for the fixed-fixed beam subjected to support motions gives useful information to develop an understanding of the structural behavior of the beam. The bending moment and the shear force of a slender beam are governed by dynamic components while those of a stocky beam are governed by static components. Especially, the maximal magnitudes of the bending moment and the shear force of the thick beam are proportional to the difference of support displacements and they are influenced by the seismic wave velocity.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.81-88
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• 2001

To study the influence of the shape of contacting bodies (especially the end profile) on slip regime, wear test is conducted in the case of the contact between tube and support. Two different end profiles of the support are used such as truncated wedge and rounded punch. During the test, 10, 30 and 50 N are applied as normal force and slip displacement varies between 10-200 $\mu\textrm{m}$. The tube and the support specimens are made of Zircaloy-4 and a specially designed wear tester is used. Tests are carried out in air at room temperature. Wear on the tube is examined by measuring microscope. Partial and gross slip regimes are classified from the observed wear shape. Surface roughness tester is also used to measure the wear depth and contour, from which wear volume is evaluated. The transition from partial to gross slip is also investigated by investigating the considerable increase of wear volume. From the result, the boundary between the partial and the gross slip is newly determined in the conventional fretting map for the present specific contact configuration. Since the transition is related with the amount of energy dissipation from the contact surface so is wear, it is regarded that wear can be restrained by designing a proper shape of support.

• Interdisciplinary Bio Central
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• v.4 no.4
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• pp.14.1-14.6
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• 2012

Splice site prediction in DNA sequence is a basic search problem for finding exon/intron and intron/exon boundaries. Removing introns and then joining the exons together forms the mRNA sequence. These sequences are the input of the translation process. It is a necessary step in the central dogma of molecular biology. The main task of splice site prediction is to find out the exact GT and AG ended sequences. Then it identifies the true and false GT and AG ended sequences among those candidate sequences. In this paper, we survey research works on splice site prediction based on support vector machine (SVM). The basic difference between these research works is nucleotide encoding technique and SVM kernel selection. Some methods encode the DNA sequence in a sparse way whereas others encode in a probabilistic manner. The encoded sequences serve as input of SVM. The task of SVM is to classify them using its learning model. The accuracy of classification largely depends on the proper kernel selection for sequence data as well as a selection of kernel parameter. We observe each encoding technique and classify them according to their similarity. Then we discuss about kernel and their parameter selection. Our survey paper provides a basic understanding of encoding approaches and proper kernel selection of SVM for splice site prediction.

• Journal of Korean Society of Steel Construction
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• v.16 no.1 s.68
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• pp.103-111
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• 2004

This paper dealt with the local buckling of H-beams investigated mainly using the parameters of load ratios. load conditions, and support boundary condition considering predicted uniformly elevated temperatures. The physical properties of the material at elevated temperatures followed EC3 Park 1.2. The local buckling of the plates in steel beams show that they are governed by the yield stress or the critical stress of the steel plates according to the ratios of b/tf, d/tw. The evaluation of uniformly heated steel beams on the local buckling considered the stress and moment ratios to the LRFD.