• Proceedings of KOSOMES biannual meeting
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• 2006.11a
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• pp.53-58
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• 2006

Along with the development of costal engineering, various type of breakwaters have been built. The main purpose of breakwaters are to provide harbour protection against waves, to stabilize beaches against erosion due to large wave action, and to provide for temporary wave protection for installation on or under water surface. This paper an application example of PIV system for analyzing the flow of Floating Breakwater with double barriers. We introduce an analysis method to predict the characteristics of flow around the neighboring fields of Floating Breakwater with double barriers in order to develop a high performance model. Flow visualization has conducted in circulating water channel by a high speed camera and etc. Flowing phenomenon according to velocity distribution and flow separation around the breakwater with double barriers were obtained by 2-D PIV system.

• Journal of Advanced Navigation Technology
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• v.19 no.5
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• pp.379-388
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• 2015

In the end of 1990's, future free flight technology had been developed and tested in America and government established the plan for free flight until 2017. Aircraft separation assurance must be secured essentially to avoid collision between aircrafts before Free Flight comes true. Now, Civil aircraft has rules about avoidance activity with traffic collision avoidance system (TCAS) but it can't apply to light aircraft. So there is a need about alternative method to apply light-aircraft because it has space and price problem to use TCAS. In this paper, TCAS algorithm has been modified and verified by simulating with LABVIEW program under ADS-B condition to get miniaturization and weight lighting cheaply. By simulating, collision alert algorithm is analyzed and verified with collision situation proposed by ICAO, and 100% checked for performing the alert announciation on all cases by TCAS standards.

• Korean Journal of Construction Engineering and Management
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• v.11 no.1
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• pp.3-15
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• 2010

Many enterprises have adopted various management techniques and IT systems such as "Process Management", "ERP" for coping with rapid business environment change and for continual growth. However, the separation problem between business process and IT system which causes reduction of business management efficiency has occurred for the lack of integration management mechanism. To solve this problem, many companies try to adopt BPM (Business Process Management) concept. The purpose of this study is to identify this separation problem in Korean construction companies which are trying to apply BPM to their business through evaluating IT system support to business processes. This study indicated the need of evaluation through current researches and case studies, then made hierarchy of home business of construction companies and analyzed IT systems for supporting business. The evaluation method is designed based on these researches. This study proposed the implications for adopting BPM in construction companies based on evaluation results analysis.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1106-1115
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• 2020

Research was conducted on the production of bio-methane for city gas, from food waste digestion gas using two membrane-separation methods(4SBR and 3SDR) in a commercial plant. A purity of 98.9% can be obtained using either method. The recovery rate of methane from the digestion gas was 88.1% for 4SBR and 79.4% for 3SDR. the ratios of bio-methane production to treated digestion gas were 53.5% for 4SBR and 49.4% for 3SDR. However, the 4SBR method had a higher ratio of returned gas(56.5%), approximately twice that of 3SDR, making 3SDR the more desirable method in terms of maximum treat capacity. Therefore, 4SBR seems more economical when the digestion gas to be treated is less than 200 N㎥/day, while 3SDR is more suited to treat gas volumes of more than 240 N㎥/day. The relative deviation of each operation index, compared to mean values, was generally greater for the 4SBR method. Additionally, the correlation coefficients between major system indexes, such as bio-methane production and bio-methane draw out pressure(which is the main control measure of membrane facility) showed that these indexes are more closely related in the 3SDR method.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.3
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• pp.373-385
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• 1998

The local Nusselt numbers have been measured for a round turbulent jet impinging on the convex surface with and without rib. Liquid crystal/transient method was used to determine the Nusselt number distributions along the surface. The temperature on the surface was measured to within .+-.0.25 deg. C accuracy using liquid crystal and a digital color image processing system. The experiments were made for the jet Reynolds number (Re) 23,000, the dimensionless nozzle-to-surface distance (L/d) from 6 to 10, the dimensionless surface curvature (d/D) 0.056, and the various rib types (height(d$_{1}$) from 1 to 2 mm, pitch (p) from 6 to 32 mm). It was found that the average Nusselt numbers on the convex surface with rib are higher than those without rib, mainly due to an increase in the turbulent intensity caused by flow separation, recirculation and reattachment on the wall surface. In addition, we compared the results by the steady-state method using the gold-film Intrex with those by the transient method.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.3
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• pp.653-661
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• 1994

In this paper the CSCM type upwind flux difference splitting Navier-Stokes method has been applied to study the ARL-SL19 supersonic/transonic compressor cascade flow. H-type grid was chosen for its simplicity in applying cyclic tridiagonal matrix algorithm along with conventional slip/no-slip boundary conditions. The thin-layer algebraic model of Baldwin-Lomax was employed for the calculation of turbulent flows. The test case inlet Mach No. was 1.612 and inlet/exit pressure ratio($P_2/P_1$) was 2.15. The results were compared with experimental results from current method were compared well in suction surface with the experiments and other computational results; however, not well in pressure surface. It might be due to the complex flowfields such as shock/boundary layer interaction, turbulence, and flow separation, etc. In the future, a proper turbulence modelling and adaptive grid system will be studied to improve the solution quality.

• Economic and Environmental Geology
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• v.31 no.6
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• pp.547-555
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• 1998

A new trigonometrical method for calculating total slip (T) of faulting is presented. The parameters for the calculations are used rake of fault striation, strike and dip of fault and of index planar structure such as bedding plane. The faults are groupped into three types. The direction of plunging of fault striation is out of a range ${\pm}90^{\circ}$ to the bedding dip direction in $360^{\circ}$ system, which is groupped into the type I. Meanwhile, the case of the direction lies in the above range can be separated into two different types, type II and type III, according to relative largeness of the angles rake of fault striation and i (see text). The type II has smaller rake than angle i and the type III has larger rake than angle i. Here I propose a few equations for calculating not only total slip (T) but strike slip (L) or dip slip (S) of the faulting. The equations are adapted selectively to the types of fault mentioned before. The limitation of the method is that the equations do not fit to polyphase faulting.

• Journal of the Korean Graphic Arts Communication Society
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• v.6 no.1
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• pp.41-57
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• 1988

Recently, it Is required to develop OCR(Optical Character Reader) along with the progress of the information processing system for Hangeul. Characters have to be recognized clearly so that OCR can be applied, Structure analysis method and lump method are used for the recognition of characters, and OCR is now available for the recognition of printed characters and handwritten alphanumeric characters having simple structure by them However, It is known that there should be much more study on the development of handwritten Hangout's OCR. This paper proposed a new method for the handwritten Hangout character recognition. The units of Initial consonant of Hangout are separated and then recognized from the utilization of the position- Information of Hangeul's units from the normalized patterns using the regression line theory. It is carried out for the extraction of the block which exists in the virtual Initial consonant region from the normalized input patterns and the calculation on maximum value (${\beta}$) of likelihood after comparing the features of separated subpattern with the initial consonant dictionary.

• KSBB Journal
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• v.5 no.2
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• pp.191-194
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• 1990

Tyrosine is a monohydrolic aromatic amino acid and DOPA is a tyrosine derivative containing dihydroxy group. DOPA can be synthesized from tyrosine by enzymatic reaction. The separation and quantitative determination of each component are very difficult in the reaction mixture. In the present study, two wavelengths giving maximum absorbance difference of each amino acid were determined using UV/VIS spectrophotometer by wavelength scanning and simple assay method was developed for the analysis of the reaction mixture of tyrosine and DOPA by measuring absorbances of reaction mixture. This method can be simply used for the analysis of the tyrosine and DOPA mixture because it does not require and procedure for the pretreatment of the reaction mixture.

• Analytical Science and Technology
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• v.14 no.6
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• pp.510-515
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• 2001

There has been an increasing need for analytical methods of dissolved total iron (tFe) that are highly sensitive, rapid, inexpensive and simple for environmental samples. A sensitive flow injection analysis (FIA) method for determining the concentration of tFe in environmental samples was developed. The proposed method required 10 minutes and only $500{\mu}L$ of sample for and analysis. The standard deviation was 5.0% at $0.5{\mu}gL^{-1}$ (n=6), and the detection limit was $0.075{\mu}gL^{-1}$. The developed method was applied to environmental samples such as tap water, mineral water, rain, snow and cloud water. Since this FIA system was free form interferences of coexisting ions commonly found in samples, sub-${\mu}gL^{-1}$ level of tFe could be easily determined without further preconcentration and separation.