• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.632-637
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• 1992

Standard transfer free energies of sodium and cupric perchlorates in water-acetylacetone solvent system have been determined by electromotive force measurements of galvanic cell and these energies of sodium and cupric ions in this solvent system have been evaluated by the tetrabutylammonium tetraphenylborate assumption as the extrathermodynamic procedure. Standard transfer free energy values of sodium and cupric ions from water to acetylacetone solvent were 5.09 and 4.16 kcal/mol at 25${\circ}C$, respectively. These values mean that acetylacetone is much weaker donor solvent to sodium and cupric ions than water. The standard transfer free energy value of cupric ion from water to mixture solvents which contain small amount of acetylacetone is changed by an unusual form. This is because of the chelate formation effect of acetylacetone to cupric ion.

• Korean Chemical Engineering Research
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• v.57 no.3
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• pp.351-357
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• 2019

This research was performed to propose domestic standard for design and management of flexible hose by analyzing chlorine leak caused by breakage of the hose in Ulsan, 2018. The leak had multiple causes but this paper focuses on analyzing the cause of breakage of flexible hose, the direct cause. According to the analysis, flexible hose that the company of the accident used for chlorine transfer was inappropriate in several aspects including material and wall thickness. And even pressure test had been conducted below operating pressure. Upon investigation on five companies that handle chlorine in Ulsan, four companies were using inappropriate flexible hose for chlorine transfer. Since there is no domestic standard for the design of flexible hose for chlorine transfer at present, it is hard to examine its design adequacy. Design standard of flexible hose used in chlorine transfer that is applicable domestically is proposed based on this research. It will contribute to the reduction in risk of breakage of the hose if the proposed standard could be applied in design and examination of flexible hose.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.1 s.5
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• pp.67-78
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• 1995

Many countries in the world have already begun digitizing spatial objects and features located in either above -or under- ground in order to conduct various spatial analyses including disaster prevention planning. At the same time, the amount of information to be exchanged will be astronomical once the information super highways will be completed to connect many countries in the world Ways to exchange and transfer of spatial information. efficiently will have to be developed in order to avoid duplicated efforts and money and to maximize the use of spatial information 1hat has already been collected. One way to maximize the efficiency in sharing spatial information is to develop a transfer standard. thus, the purpose of this paper is to review spatial data transfer standard(SDTS) with the hope that it would shed light on the development of a transfer standard for Korea

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.572-574
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• 2014

Researches on three-dimensional multimedia has been performed actively in recent years. Virtual sound technology corresponding to virtual image should be provided to implement 3D multimedia with high quality. Head-related transfer function (HRTF) plays a key role in this research area. HRTFs measured in changing azimuth, elevation, and distance for each and every subject is necessary for ideal solution. However, it is practically impossible to measure all subjects' HRTFs, so various HRTF databases have been built by many researchers. Because HRTF displays quite different aspects from subject to subject, HRTF of dummy head has been used for generic usage. However, mannequin's HRTF showed much worse performance comparing with individual case so this solution should be improved. From previous work, standardization of HRTF based on tensor-singular value decomposition method has been proposed. For effective extraction of standard HRTF, three different decomposition methods are compared in this paper.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.6
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• pp.134-139
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• 2011

This study was conducted on the characteristics of fluid flow and heat transfer in the ribbed tube used for a steam power plant. It was assumed that the air is incompressible and therefore, its density is not variable according to temperature. In addition, the gravity was ignored. A commercial code of computational fluid dynamics was used and standard k-$\epsilon$ model was used together with the energy equation included to calculate heat transfer. As Reynolds No. was low at the velocity distribution in the axial direction, the air reached hydro-dynamically fully developed region shortly but high Reynolds No. yielded late full hydro-dynamic development. The velocity distribution and non-dimensional temperature distribution were all physically reasonable and thus had a good agreement with the experimental result.

• Applied Microscopy
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• v.44 no.4
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• pp.133-137
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• 2014

We suggest a facile transmission electron microscopy (TEM) specimen preparation method for the direct (polymer-free) transfer of layer-area graphene from Cu substrates to a TEM grid. The standard (polymer-based) method and direct transfer method were by TEM, high-resolution TEM, and energy dispersive X-ray spectroscopy (EDS). The folds and crystalline particles were formed in a graphene specimen by the standard method, while the graphene specimen by the direct method with a new etchant solution exhibited clean and full coverage of the graphene surface, which reduced several wet chemical steps and accompanying mechanical stresses and avoided formation of the oxide metal.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1704-1705
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• 2007

A step-down procedure employing low voltage thermal transfer standard(LVTS) and micropotentiometer is described for the establishing the ac low voltage standards in the range of 2 mV to 200 mV below 1 MHz. Techniques are given for measuring input impedance with insertion method and calculating the loading error for the ac-dc transfer difference of the LVTS.

• Journal of radiological science and technology
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• v.43 no.1
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• pp.15-21
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• 2020

This study was purpose to evaluation of Modulation Transfer Function in Measurements by using the International electrotechnical commission standard(IEC 62220-1) which were edge device each angle by using edge method. In this study was Aero(Konica, Japan) image receptor which is a indirect Flat panel detector(FPD) was used. The size of matrix 1994 × 2430 (14"× 17" inch) which performed 12 bit processing and pixel pitch is 175 ㎛. The results of shown as MTF measurements at IEC standard. The amount of data seemed reasonable and at an MTF value of 0.1 the spatial frequencies were 2.56 cycles/mm at an angle of 2.4°. MTF value of 0.5 the spatial frequencies were 1.32 cycles/mm at an angle of 2.4°. This study were to evaluate MTF by setting each angle 2.0°~2.8° degrees the most effective optimal edge angle and to suggest the quantitative methods of measuring by using IEC.

• Korean Journal of Computational Design and Engineering
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• v.7 no.4
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• pp.240-247
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• 2002

Most commercial CAD systems provide parametric modeling functions, and by using these capabilities designers can edit a CAD model in order to create design variants. It is necessary to transfer parametric information during a CAD model exchange to modify the model inside the receiving system. However, it is not possible to exchange parametric information of CAD models based on the cur-rent version of STEP. The designer intents which are contained in the parametric information can be lost during the STEP transfer of CAD models. This paper introduces a hybrid CAB model translator, which also uses the feature tree of commercial CAD systems in addition to the macro file to allow transfer of parametric information. The macro-parametric approach is to exchange CAD models by using the macro file, which contains the history of user commands. To exchange CAD models using the macro-parametric approach, the modeling commands of several commercial CAD systems are analyzed. Those commands are classified and a set of standard modeling commands has been defined. As a neutral fie format, a set of standard modeling commands has been defined. Mapping relations between the standard modeling commands set and the native modeling commands set of commercial CAD systems are defined. The scope of the current version is limited to parts modeling and assemblies are excluded.

• Journal of Welding and Joining
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• v.17 no.1
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• pp.55-61
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• 1999

The effect of S content in welding wires on the arc stability was investigated, in the region of short circuit transfer and spray transfer. In the region of short circuit transfer, with increasing S content, average arcing time and average short circuit time were decreased. Therefore, droplet transfer frequency was increased, due to the reduction of arcing time and peak current at the moment of arc-reiginition was decreased, due to the decrease of short circuit time. In the region of spray transfer, the fluctuation degree of arc current and arc voltage became more stable, with increasing S content.