• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1997.10a
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• pp.190-195
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• 1997

The requirement of precision products about difficult-to-cut materials such as Cu and Aluminum alloy is becoming more and more. Because of soft materials, the exist narrow groves on surface are difficult to gotten off even on the polishing stage. It has been proved that Magnetic-Electrolytic-Abrasive Polishing (MEAP) is a efficient method to resolve this problem by using the nonwoven-abrasive pads together [1, 2]. In this study, through the experiments, their machining properties of newly developer polishing material of SiC, Al2O3 and diamond nonwoven abrasive pads have been proved. Through the experiments, the optimal machining conditions on larger cylinder shape workpiece of Cu and Aluminium alloy have been found, through the Taguchi[3] method the optimal machining conditions can be selected.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.607-612
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• 2000

A slitter, also called a roll slitter or rewinding machine, is a sort of machinery to cut sheet materials in rolls continuously in the longitudinal direction. Recently slitter line users have requiring higher wuality and precision in products in addition to high productivity. In this paper, on effect of clearance on shear planes in slitting of S.K.B(shrinkage Bnad) is performed by using finite element method. The results obtained are as follows: (1)Load stroke curves show decreasing maximum force when increasing the clearance. (2)Effective strain decreases when the clearance increases. (3)Deformation is concentrated along the very narrow shear band.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.256-259
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• 2008

An micro-probe tip must be manufactured using thin film to evaluate integrity of the semiconductor with narrow distance between pads. In this study, fatigue tests were performed for BeCu thin film which is used in micro-probe tip of semiconductor test machine. The thin film was manufactured by electro plating process, and the specimens were fabricated by wire-cut electric discharge method to make hour glass type specimen of $5000{\mu}m$ width, $29200{\mu}m$ length and $30{\mu}m$ thickness. The fatigue test of load control with 10Hz frequency was performed, in ambient environment. The fatigue cycles were tension-tension with mean stress, at stress ratio, R=0.1.

• Journal of Auto-vehicle Safety Association
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• v.7 no.2
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• pp.25-31
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• 2015

This paper presents a performance evaluation procedure for advanced emergency braking (AEB) system. To guarantee the performance of AEB system, AEB test scenario should contains various driving conditions which can be occurred in real driving condition. Also, performances of each elements of AEB system, such as sensor, decision, human machine interface (HMI) and control, should be evaluated in various situations. For this, driving conditions, road types, environment, and elements of AEB system were introduced. Test scenario has been designed to represent the real driving condition and to evaluate the safety performance of AEB system in various situations. To confirm that the proposed AEB test scenario is realistic and physically meaningful, vehicle test have been conducted in two cases of proposed AEB test scenario: subject vehicle cut-out scenario and narrow street turn left scenario.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.14 no.1
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• pp.11-21
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• 1989

In this paper, a GMSK modulator was implemented with a gaussian lowpass filter using digital signal processing, a phase integration, D/A convers and auxiliary circuits. The relatively narrow bandwidth of power spectrum of the GMSK modulator is observed when the cut off frequency (B T) of the gaussian baseband filter is varied. In a demodulator, a discriminator type circuit is used. Using the above degital radio GMSK modem, BER is theoretically derived and experimentally measured when 16Kbps PRBS data is transmitted under Rayleigh fading and additive white gaussian noise conditions.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.21-26
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• 2007

This paper presents an impedance-based structural health monitoring (SHM) technique considering temperature effects. The temperature variation results in a significant impedance variation, particularly both horizontal and vertical shifts in the frequency domain, which may lead to erroneous diagnostic results of real structures. A new damage detection strategy has been proposed based on the correlation coefficient (CC) between the reference impedance data and a concurrent impedance data with an effective frequency shift which is defined as the shift causing the maximum correlation. The proposed technique was applied to a lab-sized steel truss bridge member under the temperature varying environment. From an experimental study, it has been demonstrated that a narrow cut inflicted artificially to the steel structure was successfully detected using the proposed SHM strategy.

• Lingua Humanitatis
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• v.1 no.2
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• pp.221-228
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• 2001

This article criticizes Professor Nam-Sik Park's understanding and proposals on the educational implementation of English Linguistcs in Korea. First of all, this article claims that 'studying English' cannot be the primary goal of 'doing English linguistics', arguing that the curriculum related to the English linguistics should not be altered on the basis of the practical use of English linguistics. The article furthermore criticizes Professor Park's narrow view on the 'practicalism'. Criticism is also addressed to Professor Park's undesirable and unduly clear-cut dichotomy on 'data' versus 'theory', 'subject' versus 'object', 'theoretical linguistics' versus 'applied linguistics', and 'English linguistics' versus 'linguistics', while the author's fundamental emphasis is given to the idea that humanistic understanding of English language is neccessary for proper and extensive comprehension and application of English linguistics in Korea.

• Journal of the Korea Fashion and Costume Design Association
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• v.18 no.1
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• pp.149-168
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• 2016

The Saka were a large group of Eastern Iranian nomadic tribes on the Eurasian Steppe. The sythian figures shown on the Persian reliefs are esteemed as the only empirical material in the range of scythian costume researches. The study of the scythian culture is an important part in the research of possible connections of our cultural roots with this region. The investigation was initiated by the theory, that the korean people emigrated from the Eurasian region, so that their origin can linked to eurasian riding people. The aim of this study is to organize the scythian clothingform in a typological system. This results shall be used as the starting point for research investigating the origin of the korean clothingform. This study refers to data, which has been extracted from reviews of literature, articles and excavation data of German Archaeological Institute. Results of this study are as follows: The basic form of clothing shown on the Persian reliefs is the upperjacket with narrow sleeve and trousers. This basic form is divided into two different types. 1)The median tunicform upperjacket('Sarapis') and median narrow trousers('Anaxsirides'), which is bound with its end shoes. 2)The Scythian 'Cutaway' upperjacket that is cut from the front in the middle to the knee with the diagonal lines and relatively wide trousers. They wore high pointed hats with flaps over ears and the nape of the neck. The first median type is dated from the $6^{th}$ century BC. and the second type can be found on reliefs from the $5^{th}$ century BC. Reliefs. In the meantime appeared a mixed form, namely scythian Jacket and median trousers. From this analysis could be observed that scythian clothingform has changed by median type to the scythian type. The Scythians shown on the Persian reliefs are divided into three group according to the regions where they lived: Saka-paradraya, Saka-tigraxauda, Saka-haumavarga. Clothingstype is different depending on the group. The clothesform is also used as a good parameter to distinguish scythian groups.

• Economic and Environmental Geology
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• v.17 no.4
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• pp.289-298
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• 1984

Uraniferous black slates of the Okchon sequence occur in Koesan (northeast) through Miwon-Boun (middle) to the southwest off Taejon (southwest) within the Okchon fold belt. The Uraniferous balck slates in the southwest off Taejon are particularly well developed in Chubu (northeast) and Moksso-ri (middle) areas whereas they are less developed in Jinsan (southwest) area. The uraniferous beds range from less than a meter to 40 meters in thickness and range from less than 0.02% $U_3O_8$ (cut-off-grade) to 0.05% $U_3O_8$ in the southwestern district off Taejon. Electron microprobe analysis of uranium-minerals found in graphitic slate samples enables to estimate their major compositions semi-quantitatively so that uraninite, ferro-uranophane and chlopinite are tentatively identified. Uranium-minerals are closely associated with carbon and metal sulfides. Correlation analysis of trace element concentrations revealed that U and F.C., and U and Mo are lineary correlative respectively and their correlation coefficients are positively high whereas those of U and V, U and Mn, and U and Zr are negatively low, implying that uranium mineralization has been closely related with concentrations of carbon and molybdenum. Stable isotope analyses of pyrite sulfur range widely from +11.5% to -23.3% in ${\delta}^{34}S$ values whereas those of graphite carbon fall within a narrow range between -23.3% and -28.9% in ${\delta}^{13}C$ values. The wide range of ${\delta}^{34}S$ values suggests that the sulfur could be of meteoric origin rather than of igneous source. The narrow range of ${\delta}^{13}C$ values, which are close to those of coal, indicates that the graphite is organic carbon in origin. Therefore, it is concluded that the uranium mineralization in the Okchon sequence took place primarily in sedimentary environment rich in organic matter and sulfide ion, both of which served as the reducing agents to convert soluble uranyl complex to insoluble uranium dioxide.

• Journal of Plant Biology
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• v.17 no.3
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• pp.118-126
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• 1974

Mulberry plants cultivated in mid-Korea were studied on the growth habitat, canopy type, productive structure and vertical light intensity in relation to the quality of mulberry leaves for sericulture. The growth in length of new branch of summer cut mulberry in spring was vigorous on the uppermost of old shoot. Numbers of leaves on a branch were barely 4 leaves on lower than 20th branch from base, but those were 13 leaves on higher than 24th branch. Area of leaves completely expanded was broad on high branch, but narrow on low one. The form of canopy, the type of productive structure and the vertical light distribution depend upon varieties of cultivated mulberry plants were classified according to characteristic of each variety in two groups, respectively; globular and columnar form in canopy, broad leaves and narrow leaves types in productive structure, and seriously obstructured the light and fairly transmitted the light into lower leaf stratum invertical light distribution. Out of varieties of mulberry investigated, Suwon No. 4 and Rosang were belong to the former characters, but Illchiroe and Kaeryangsubun were to the latters. The values of leaf dry matter index and dry matter production produced by leaves were increased in direct proportion to the height of leaf stratum; the leaf dry matter index of the uppermost leaf was twice as much that of the lowest, and the dry matter production by the highest leaf was 17 times compared with that by the lowest leaf. It is assumed that the meagre leaves occurred in the lower leaf stratum of Suwon No. 4 and Rosang were caused to diminished the dry matter index and dry matter production in the under leaves of plant, which were affected by receiving the weak light.