• Proceedings of the Korean Fiber Society Conference
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• 1996.04a
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• pp.64-68
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• 1996

PP-EVOH(poly(vinyl alchol-co-ethylene)) blends were prepared by the mixing of polypropylene and poly(vinyl alcohol-co-ethylene) containing 38mol% of ethylene units (EVOH38) at melt state above PP melting temperature. The materials were characterized by using dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and contact angle measurement to detemine the glass transition, meltin, decomposition temperatures, and wettability respectively. From the results, PP-EVOH(poly(vinyl alcohol-co-ethylene)) blends exgibits partial miscibility.

• Journal of the Korean Society of Safety
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• v.10 no.2
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• pp.77-83
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• 1995

An electrostatic reducer of a multi-pole high DC voltage applied type and a high frequency square wave voltage applied type have been studied to eliminate effectively and safely electrostatic charge on a dummy charged material. As a fundamental experiments, measurement were made on the decay time as a function of distance between electrostatic reducer and charged body, skewed angle of electrostatic reducer installed and wind speed of generated ions(＋ or －) by electrostatic reducer with high DC voltage and high frequency square wave voltage. Based oil the results above, a appropriate installation and method were produced as a trial for factory.

• Analytical Science and Technology
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• v.36 no.4
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• pp.198-203
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• 2023

The reaction of cis-protected (Me4en)Pd(II) species with potentially multidentate bis(benzylthio)methylenepropanedioate (L) was carried out to obtain a monometallic compound, [(Me₄en)Pd(L)], in O,O'-coordination mode. The bis(benzylthio)methylene group was bent strikingly from the palladium square plane at the dihedral angle of 70.40°. The physicochemical properties of the present palladium(II) compound were fully characterized by means of infrared and nuclear magnetic resonance spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction measurement.

• Journal of the Korean School Mathematics Society
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• v.21 no.1
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• pp.19-37
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• 2018

In this study, the actual state of teaching seven extensive quantities (time, length, capacity, weight, area, angle measure, volume) of measurement domain are analyzed comparatively between the 2015 revised elementary school mathematics curriculum in Korea and the 2017 revised elementary school mathematics curriculum in Japan in terms of comparison in measurement, direct measurement, indirect measurement, and estimation in measurement. From the results of this comparative analysis, some implications for discussion on the development of the next elementary school mathematics textbook and the next elementary mathematics curriculum can be suggested. First, it is necessary to discuss on clarifying the range of handling of comparison, direct measurement, indirect measurement, estimation of seven extensive quantities respectively. Second, it is necessary to discuss on doing direct comparison when intuitive comparison is difficult. Third, it is necessary to discuss on reconsidering indirect comparison of weights. Fourth, it is necessary to discuss on reconsidering measurement using arbitrary units in case of angular measures. Fifth, it is necessary to discuss on dealing with estimating the area of $1cm^2$ and $1m^2$ and the volume of $1cm^3$ and $1m^3$ for the purpose to make rough guesses their size respectively.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.5
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• pp.357-364
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• 1998

To investigate accuracies between intensity method and count method for measurement of the fiber orientation distribution, fiber orientation function is derived by drawing simulation figure for the fiber orientation as varying fiber aspect ratio, fiber area ratio, and fiber orientation state, respectively. The values of fiber orientation function measured by intensity method and count method are compared with the calculated ones from simulation figures. The results show that measurement accuracy of fiber orientation angle distribution obtained by count method is by 4% higher than that by intensity method.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.5
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• pp.178-187
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• 1997

For the experimental measurement of heat flux of DI diesel engine combustion chamber, the instantaneous temperature probes and data acquisition system were developed. By the analysis of measured temperatures at the cylinder head, the temperature at the point 3 which is located between intake and exhaust valve was higher than that of the other points. Temperatures at the point located mear the exhaust valve were higher than those of intake valve. The instantaneous and mean temperature at the cylinder head increases proportionally to the increase of the engine speed, while the temperature swing varies inversely. Temperature swings have influence on the maximum heat flux values from gas into head surface. It has been verified that these probes and data acquisition system perform well by the comparison of the trend of instantaneous temperature variation with that of measured combustion chamber pressure variation with respect to crank angle. It is presumed that these probes could be used in the measurement of other parts of combustion chamber as piston, cylinder wall etc. for the future study.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.4
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• pp.614-621
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• 2016

Micro-Doppler (MD) shift caused by the micro-motion of a ballistic missile (BM) can be very useful to identify it. In this paper, the MD signatures of three scale-model BMs are investigated using a portable measurement system. The measurement system consists of an X-band 2-by-2 phase comparison mono-pulse radar, and a mechanical device that can impart controlled spinning and coning motions simultaneously to a model to yield the MD signature that replicates the characteristic of each target and the corresponding micro-motion. The coning motion determined the overall period of MD, and the spinning motion increased its amplitude. MD was also dependent on aspect angle. The designed system is portable, and can implement many micro-motions; it will contribute to analysis of MD in various situations.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.2
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• pp.222-231
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• 2010

This paper presents numerical analysis of measurement errors of ground electrode using the fall-of-potential method. In order to analyze ground resistance error according to the positions of auxiliary probes, firstly, national and international standards were researched. Secondly, numerical ground resistance error of hemispheric electrode was analyzed according to the locations of auxiliary probes and the angle between probes. Then, error-reduced positions of auxiliary probes were shown according to the distance to auxiliary current probe versus ground electrode size. Finally, error compensation method was presented. The results presented in this paper provide useful information regarding ground resistance error of alternative positions of auxiliary probes in case that the auxiliary probes could not be located at the proper position in such cases as there are buildings, roadblock or underground metallic pipe at that position.

• Transactions of the Korean Society of Mechanical Engineers
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• v.7 no.2
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• pp.161-167
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• 1983

In this study the phenomenon of cutting stress which arises on cutting tools and work pieces in cutting process is investigated by rake angle of cutting tools and feed for this measurement, P$_{s}$-1 (high modulus, photolastic Inc.) was used as a cutting tool, P$_{s}$-3 (medium modulus, photolastic Inc.) was used as work piece and reduction apparatus was attached to the head stock, and orthogonal cutting was adapted as a cutting method and transparent glass was used to block the strain in the orientation of thickness. The followings are the results of this study. (1) Photoelastic experimental equipments have made it possible to make dynamic measurement and analyze stress distribution in cutting tool and work piece surface which has hitherto been conducted only in static measurement and analyzing method. (2) The maximum stress arising at tools and work pieces in cutting process is on the tool edge tip, and the maximum stress arising on the tip of cutting tools is equal to that on the contacting area of work pieces in values. (3) The distributions of maximum shear stress on certain parts of the cutting tools and work pieces are as follows; for cutting tools, .alpha.=12.deg., .alpha.=0.deg., .alpha.=-12.deg. in order, and for work pieces, .alpha.=-12.deg., .alpha.=0.deg., .alpha.=12.deg. in opposite order.der.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.1-8
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• 2004

One of the most frequently used method for measurement of the degree of sizing (viz., hydrophobicity) is the Stockigt test. However, the Stockigt test was influenced by various factors such as dropping height, dropping amount, dropping speed and viewing angle. The resultant data of the sizing degree on the same specimen also varied according to different testers. Thus, the Stockigt test should be modified to be regarded as a highly reliable and reproducible standard method. For modifying the Stockigt test, it was required to quantify red coloration by reaction between 1％ ferric chloride and 2％ ammonium thiocyante during Stockigt testing. The cameras capturing the serial images during the red coloration process were the CMOS (Complementary Metal Oxide Semiconductor)-type and CCD (Charge Coupled Device)-type cameras. For measurement based on KS M 7025, the CCD-type camera must be used due to its high resolution, and on the other hand, for measurement based on Tappi Useful Method 429, the CMOS-type camera may be used owing to its low resolution. It was needed to covert the RGB values of a droplet image into HSV(Hue, Saturation, and Value) values because the human eyes are much closer to HSV than RGB. Among HSV values, the Hue value was accepted as the most reliable index consistent with the red coloration process by excluding the surrounding conditions such as light, tester's movement etc.