• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.877-887
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• 2015

We have proposed a new method for estimating the viscosity of the composite. In this paper, we have developed a device for measuring the injection mold cavity pressure. This makes it possible to verify the accuracy of the viscosity in CAE D/B in real time by measuring the melt pressure in the mold, and comparing this with the simulated pressure from the CAE analysis. Materials used in this study is a PP(Polypropylene), PP/LGF30%(Polypropylene/long glass fiber 50% composite) and PA66/LGF50%(Polyamide 6,6/long glass fiber 50% composite). The viscosity data for PP and PP long fiber composite have already been built, but the one for PA66 long-fiber composite does not exist because it is a newly developed material. Thus we obtained the viscosity curve of PA66/LGF50% by this system. Then, the viscosity curves from conventional viscometer were also compared with the viscosity obtained by the our method. And, we proved the accuracy of the CAE data of PP. In case of PP/LGF50% which is highly viscous and complex material, we improved the existing CAE data.because there was a difference between the measuring data and the CAE data.

• Journal of Korean Society of Steel Construction
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• v.16 no.4 s.71
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• pp.415-423
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• 2004

To investigate the long-term corrosion resistance of an uncoated weathering steel, an important outdoor constructional steel material, skyward surfaces of the weathering steel and a control steel initially exposed to rural and industrial atmospheres for 9 years were electrochemically tested in neutral artificial rain in terms of electrochemical potentials, impedances, and anodic potentiodynamic polarization curves. Their results were then discussed. A quite passive and stable rust layer to the artificial rain was well formed on the skyward surface of the weathering steel exposed to the industrial and rural atmospheres, and its corrosion rate in the artificial rain was measured to be about a low $3{{\mu}m}/y$. Continuous immersion of all the weathered surfaces in the artificial rain revealed the gradual degradation of the weathered corrosion layers on the steel, resulting in a cathodically controlled corrosion of the substrate steel by the electrochemical measurements. Alloy components of the weathering steel were found to retard the degradation of the weathered corrosion layers on the steel in the artificial rain. For better corrosion evaluation of the weathering steel, more electrochemical measurements of surfaces that have been exposed for more than 9 years to more closely simulated atmospheric waters are needed. These measurements are almost non-destructive and can provide online and in situ information on the corrosion rate, the development of corrosion and the conditions of rust layers on any interested surface and at any exposure time of the steel, so they can be effectively applicable to the corrosion evaluation of steel structures such as bridges, towers, and architectures by forming an electrochemical cell on an interested structural surface and by using a portable electrochemical instrument.

• Radiation Oncology Journal
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• v.14 no.3
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• pp.247-253
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• 1996

Purpose : The dose calculation program for the Buckler type remote after-loading system was developed. This program also can be used to calculate dose for various sealed sources. Materials and Methods : We determined the source length and distribution by dividing the program disk to 72 points. The dose rate for the each program disk and source was calculated. The dose rate table for the xy coordinate was established. The dose rate for the interesting points of the patient were calculated by using this table, We also made isodose curve from this calculations. Results : The storage size for the dose rate table were increased. But the calculation of the dose rate for the patient were carried out rapidly. So we could get real time calculation. Conclusion : By using this program, we could calculate the dose rate for the various points of the patient quickly and accurately. This program will be useful for the treatment with various linear sources.

• Analytical Science and Technology
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• v.16 no.2
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• pp.102-109
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• 2003

Microwave digestion and solid-state extraction were studied for determination of trace aluminum{Al(III)} in human urine samples. A mixed acid of nitric acid and hydrogen peroxide was added to urine samples, organic materials were destructed in a home microwave oven and dried in a drying oven. The dried residues were dissolved in a sulfuric acid solution. The solution was eluted through a XAD-4 resin column adsorbed with 8-hydroxyquinoline(Oxine, HQ). Al(III)-8-hydroxyquinolinate complex was formed in the column and eluted with 0.5 M nitric acid solution. The Al(III) eluted was determined by graphite atomic absorption spectrophotometry. Various experimental conditions of followings were investigated for the optimization : the type of acid to dissolve the residues, the amount of HQ adsorbed on the resin, the pH of sample solutions, the type and concentration of acid to elute the complex from column and so on. The contents of Al(III) in real samples were determinated by a calibration curve method. The recovery in standard spiked samples was 94~101% and the detection limit of this procedure was 0.05 ng/mL.

• Analytical Science and Technology
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• v.27 no.2
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• pp.108-113
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• 2014

The harmful materials as volatile organic compounds (VOCS) that is easy for gas to be changed from liquid on ambient temperature, those should be controlled by Korea Chemicals Management Association. The VOCs samples should be collected directly in place so that those could be analyzed. Generally but it couldn't avoid to have the risk of analyst. Moreover, if there is the place limited to entrance, it is impossible to collect directly and measure. Owing to such problem, it tried to be solved by open path FT-IR spectrometer that could be studied on the combustion gases within long path and VOCs samples were tried to measure to large volume by remote and real time. Firstly, it was to investigate optimized measured length between the system and benzene sample of VOCs. As result, The optimized measured length was confirmed with 15 meter length and the qualitative analysis could be measured on seven VOC samples. The calibration curve as quantitative analysis of benzene samples could be worked. On the basis of the result, the system as remote monitor could show to have potentiality.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.255-261
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• 2014

The generation amount of radioactive waste has been rapidly increased by increase of the usage of radioisotope source in medical field. Especially, the use of the radioactive source of I-131 with short half-life of 8.02 days used in treatment of thyroid has been increased, and all of the wastes concerned have been disposed by means of the self-disposal method. IAEA proposed criteria for clearance level of waste which depends on the individual (10 ${\mu}Sv/y$) and collective dose (1 man-Sv/y), and concentration of each nuclide (IAEA Safety Series No 111-P-1.1, 1992 and IAEA RS-G-1.7, 2004). In this study, various radioactive wastes in medical fields are collected and measured for establishing the disposal methods and procedures of radioactive wastes. In addition, comparison evaluation of decay storage period between the half-life which was calculated by attenuation curve based on real measurement and analytical half-life is considered. With comparing the theoretical half-life and the effective half life(7.72 days) which was based on the decay equation of measured data, it is resulted in the theoretical half-life is longer than effective half-life. The storage period of radioactive waste for self-disposal may be curtailed. The result of this study will be proposed as ISO standard.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.200-210
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• 2017

This Research is focused on ancient battle formation basing on the layout drawing of Yijinchongbang (manuals of learning military formations) in a strategy book in the late Joseon dynasty. The research topic is the principles of organic composition of battle formation and battlefield operating system by reforming the basic model of ancient battle formation. The research method is comparative analysis by reforming the battlefield operating system of types of disposition such as Obangjindisposition(Bangnjin; battle formation, Jikjin; direct battle formation, Gokjin; bend battle formation, Wonjin; round battle formation, and Yejin; keen battle formation), and Hyunmoojindo; turtle battle formation, Paljindo; all-rounder battle formation, Yookhwajindo; six flowers battle formation, Gugunjindo; nine forms battle formation. From the study results, Standoff Bombing of the battle formation in the late Joseon Dynasty basically started out from magic battle formation, but was then transformed into square, rectangle, pentagon, and circle. Also, the battle array composition used a 5-linear structure and was composed of 5 systems of circulation such as rectangle, square, diagonal, curve, and circle. The research findings elucidate the battlefield of the Joseon dynasty by establishing the real battle formation, and thus have military and academic value in suggesting possible tactics that can be used by modern training of military.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.4
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• pp.274-279
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• 2009

To determine the critical level for optimum maturity of flue-cured tobacco leaves (KF118) at the stalk position from cutter to tips, the reflectance index using ground-based remote sensors and chlorophyll meter were investigated. The sensors estimated were Crop $Circle^{TM}$ (Holland Scientific), Green $Seeker^{TM}$ (Ntech Industries), Spectroradiometer (LICOR, LI-1800), Chlorophyll meter (SPAD502, Minolta), and Field $Scout^{TM}$ Chlorophyll meter (CM-1000, Spectrum). The L, a, b values and greenness for flue-cured leaf were measured and estimated for correlation with sensor's measurement of harvested leaf. On a reflectance curve of 340nm~1100 nm, the reflectance peaks on 550nm and 675 nm for the harvested leaf were lowered as change from light green to darker green. Darker green leaf harvested produced darker flue-cured leaf. The reflectance at 675 nm for flue-cured leaf decreased as greenness increased in the harvested leaf. This result means that the red edge band of 675 nm wavelength is related to the absorbance of chlorophyll for photosynthesis. The greenness of flue-cured leaf showed significantly positive correlation with the entire reflectance indexes for harvested leaf while the L value by colorimeter showed negative correlation with greenness of cured leaf. The critical level for optimum maturity of harvested leaf were less than 22, 135, and 0.43 for SPAD reading, CM-1000 reading, and gNDVI by Crop $Circle^{TM}$, respectively. Consequently, ground-based remote sensing providing a non-destructive real-time assessment of plant greenness could be a useful tool in the selection of optimum maturity of flue-cured tobacco leaves in relation to high quality of flue-cured tobacco.

• KDI Journal of Economic Policy
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• v.31 no.2
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• pp.15-45
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• 2009

This paper estimates the term structure of interest rates with the setup of 3-factor no arbitrage model and investigates the trend of term premia and the effectiveness of changes in policy interest rates. The term premia are found to be high in a three-year medium term objective, which can be interpreted as reflecting the recognition of investors who expect a higher uncertainty in real activities for the coming three years than for a longer term. Then, in order to look into the effect of policy interest rates after the recent change of benchmark interest rate, this paper analyzes the effects of the changes in short-term interest rates of the financial market on the yield curve of the bond market at time of change. Empirical results show that the discrepancy between call rate, short-term rate in money market, and instantaneous short rate, short-term rate in the bond market, is found to be significantly widened, comparing to the periods before the change in benchmark interest rate. It is not easy to conclude clearly for now whether such a widening gap is caused by the lack of experiences with managing new benchmark interest rate or is just an exceptional case due to the recent turmoil in the global financial market. However, monetary policy needs to be operated in a manner that could reduce the gap to enhance its effectiveness.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.6
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• pp.121-126
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• 2017

Recently, a lot of people use touch-pen devices such as smart phones and tab computers. To generate the picture and text, a user can give input or control the touch-pen device through simple or multi-touch gestures by touching the screen with a special stylus pen and/or one or more fingers. The accuracy and response time from the moment of contact with the touch board is very important to the touch device. Therefore, research is needed to find a way of removing the noise included in the touch signal quickly and efficiently. In this paper, we propose a method for removing a noise mixed in with a touch point coordinate which has been caused by a input pen on the touch screen. For effective filtering, the fast sampling of the coordinate corresponding to the noise from the input signal is required primarily. Secondly the total compensation of the touch coordinates using the characteristics of the B-Spline curve is applied to correct coordinates of the points. This method can ensure a real-time response than other algorithms. The applied performance evaluation method is comparing error pixels with evaluation values by dividing 10 intervals on the touch pad diagonally. Usually the average error is 7.1 pixels but our proposed method shows an average 4.1 errors. Therefore, our proposed touch pen method can express the input signal on the coordinates more correctly.