• Proceedings of the Computational Structural Engineering Institute Conference
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• 1994.04a
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• pp.113-119
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• 1994

Vibration control of offshore structures subjected to wave loads is studied. The reduction of the dynamic responses of offshore towers subjected to wind generated random ocean waves is an important issue in the aspect of serviceability, fatigue life and safety of the structure. In this thesis, the effectiveness of the active tuned mass damper(ATMD) compared with the tuned mass damper(TMD) is mainly considered. Instantaneous optimal control scheme is employed for the active vibration control and Kalman filtering technique is used for the estimation of unmeasured response of structures. In practice, displacements and velocities could not be measured as easily as accelerations. So the state estimation methods like Kalman filter is very important. Numerical simulation is conducted for guarantee the effectiveness of ATMD for offshore structures.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.3
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• pp.29-34
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• 2009

Diesel particulate filter (DPF) has been developed to optimize engine out emission, especially particulate matter (PM). One of the main important factors for developing the DPF is estimation of soot mass being accumulated inside the DPF. Evaluation of pressure drop over the DPF is a simple way to estimate the accumulated soot mass but its accuracy is known to be limited to certain vehicle operating conditions. The method to compensate drawback is adoption of integrating time history of the engine out PM and burning soot. Present study demonstrates current status of the soot estimation methods including the results from the engine test benches and vehicles.

• Journal of the Korean Institute of Educational Facilities
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• v.24 no.1
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• pp.3-10
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• 2017

This study is to analyze the remodeling method of library in terms of space extension method and urban regeneration by repurposing function in unused facilities through case study. In many case of library extension, horizontal extensions are more frequent than vertical extensions, because there are limits to extend vertically due to high live load estimation by book stacks. Extension schemes was organized by new building extension method in connection with existing buildings, attaching method small scaled mass or linear mass to existing building, connecting method a plurality of existing small buildings, vertical extension method on the top of the structure, underground extension method using special structure. Unused facility remodeling to the library, large scaled buildings can be developed completely to the function of the library through the relocation of the space, while small scaled building needs spatial extension. In the case of spatial extension, existing space that was used for other purposes can be used as a reading room or office, avoiding high live load estimation.

• Journal of the Korean Wood Science and Technology
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• v.40 no.5
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• pp.352-362
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• 2012

Mass transfer behavior in wood was estimated through its microscopic structure. The diffusion coefficients which were decided by theoretical equations are influenced by different anatomical properties of wood. From the experiment, the moisture flux was linear to the square root of time. The diffusion coefficients had a regular tendency during the time elapse. During the modeling, it is necessary to understand the limitation of parameters and consider the particular situation to be simulated. In hardwood, because the apertures were not considered, tangential mass transfer simulation was totally different from experiment. As a result, a hardwood model design should consider the apertures which are even on the fiber walls.

• Mass Spectrometry Letters
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• v.8 no.1
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• pp.1-7
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• 2017

Studies performed on heterogeneous reactions of hydroxyl radicals (OH) in aerosol materials of tropospheric interest are presented, focusing on the chemical ionization mass spectrometric approach. Kinetic investigations of these reactions reduced deviation in the estimation of OH concentration in the troposphere by atmospheric modeling from field measurements. Recently, OH uptake was investigated under wet conditions to acquire kinetic information under more realistic conditions representative of the troposphere. The information on the mechanism and kinetics of OH uptake by tropospheric aerosol materials will contribute to the updating of atmospheric models, allowing a better understanding of the troposphere.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.50.3-51
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• 2017

Discovered in the South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey, the galaxy cluster SPT-CL J0205-5829 at z = 1.322 might be the most massive known SZ-selected galaxy cluster at z > 1.2. The SZ and X-ray combined mass estimate is $M500=(4.8{\pm}0.8){\times}10^{14}M_{\odot}$. To confirm this extreme mass, we perform weak lensing analysis of SPT-CL J0205-5829 using HST data. Our analysis produces a mass estimate consistent with the previous results obtained from non-lensing methods. In this poster, we describe details of the method including shape measurement, PSF correction, source selection, and mass estimation. We also present a two-dimensional mass map and compare this to the galaxy distribution.

• Journal of the Korean Ceramic Society
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• v.49 no.1
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• pp.37-42
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• 2012

Mass transport near grain boundary in a magnetite bi-crystal has been estimated at 823 K by finite element method. Mass transport near grain boundary strongly depends on the diffusivities along grain boundary. If grain boundary diffusion has the same oxygen activity dependence as lattice diffusion, there is no mass transport between grains and grain boundary. On the other hand, mass transport between grains and grain boundary is observed in the case that grain boundary diffusion has different oxygen activity dependence.

• Structural Engineering and Mechanics
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• v.51 no.5
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• pp.823-845
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• 2014

Success in the excavation of foundations is commonly known as being very important in asserting stability. Furthermore, when the subjected formation is rocky and the use of explores is required, the demands of successful blasting are multiplied. The quick and correct estimation of excavation's characteristics may help the design of building structures, increasing their safety. The present paper proposes a new classification system which connects blastability and rock mass quality. This new system primarily concerns poor and friable rock mass, heavily broken with mixture of angular and rounded rock pieces. However, it should concern medium and good quality rock mass. The Blastability Quality System (BQS) can be an easy and widely - used tool as it is a quick calculator for blastability index (BI) and rock mass quality. Taking into account the research calculations and the parameters of BQS, what has been at question in this paper is the effect of BI magnitude on a geological structure.

• Bulletin of the Society of Naval Architects of Korea
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• v.7 no.2
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• pp.3-18
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• 1970

An investigation was made for the added mass moment of inertia induced by the rotational motion of the cylinder with hull section on water in order to obtain the information to estimate the natural frequency of the torsional vibration of ships. The special consideration to the effect of the draught upon the added mass moment of inertia is taken into account in the study. In this paper, the general expression for the added mass coefficients of moment of inertia of arbitary two dimensional forms induced by the torsional vibration, was derived by the author. Hence, the coefficients for these forms are represented as functions of parameters, the section area coefficient and draft beam ratio, from which the added mass coefficients for arbitrary forms can be obtained. The result was shown in a chart for estimation of the added mass moment of inertia induced by the torsional vibration, as first trial, for the convenience of practical use.

• Mass Spectrometry Letters
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• v.15 no.2
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• pp.107-119
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• 2024

We aimed to develop a suitable quantification method for detecting asparagine deamidation and aspartic acid isomerization in peptide mapping using LC-MS. Our assessment of its validity and suitability involved comparing its quantitative findings with those obtained from cation-exchange chromatography and capillary electrophoresis methods. By subjecting trastuzumab to rigorous conditions to induce these modifications, we validated the efficacy of this new analytical method in peptide mapping via LC-MS, evaluating both qualitative and quantitative aspects of asparagine deamidation and aspartic acid isomerization. Our investigation underscored the significance of enzyme selection and the presence of miss-cleaved or non-specific peptides in achieving accurate quantitative results. The experimental results demonstrated a strong correlation with results from cation-exchange chromatography and capillary electrophoresis analyses, confirming the reliability of the LC-MS based peptide mapping approach.