• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1888-1893
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• 2011

Considering the dynamic performance and stability of railroad vehicles has begun to grab the attention because of developing the high speed train recently. A development based on an analysis of dynamics and verification has to be required to study the stability of vehicle performance. Several ways of analysis were using the look-up table to apply the wheel-rail contact characteristics quickly, whereas there is a constraint of the wheelset lateral displacement. In this study, an development of searching the wheel-rail contact position has been provided. The 2-point contact between wheel and rail during the driving condition can be calculated by numerical analysis. Moreover, a reliability is verified by comparing the result with a commercial program.

• Bulletin of the Korean Mathematical Society
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• v.54 no.6
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• pp.1893-1912
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• 2017

In this paper, we aim to construct a nonstandard finite difference (NSFD) scheme to solve numerically a mathematical model for cholera epidemic dynamics. We first show that if the basic reproduction number is less than unity, the disease-free equilibrium (DFE) is locally asymptotically stable. Moreover, we mainly establish the global stability analysis of the DFE and endemic equilibrium by using suitable Lyapunov functionals regardless of the time step size. Finally, numerical simulations with different time step sizes and initial conditions are carried out and comparisons are made with other well-known methods to illustrate the main theoretical results.

• Korean journal of applied entomology
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• v.42 no.1
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• pp.15-20
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• 2003

Five species of the genus Aulacaspis (Sternorrhyncha, Diaspididae) from Korea were redescribed and illustrated for the morphological characters of adult females with the information of known host plants. Among them, Aulacaspis spinosa (Maskell, 1897) is reported for the first time from the Korean Peninsula. A key to species is given for the adult females.

• Journal of Mechanical Science and Technology
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• v.17 no.12
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• pp.1886-1893
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• 2003

This paper examines the parameter observability of a calibration system that consrains a mobile platform to a planar table to take the calibration data. To improve the parameter observability, we find the optimal configurations providing the calibration with maximum contribution. The QR-decomposition is used to compute the optimal configurations that maximize the linear independence of rows of an observation matrix. The calibration system is applied to the parallel type manipulator constructed for a machining center. The calibration results show that all the necessary kinematic parameters assigned in a Stewart-Gough platform are identifiable and convergent to desirable accuracy.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1893-1894
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• 2008

Advances in hardware and wireless network technologies have placed us at the doorstep of a new era where small wireless devices will provide access to information anytime, anywhere as well as actively participate in creating smart environments. In this paper, we propose location-aware clustering method in wireless sensor networks. Previous clustering algorithm assumes that all nodes know its own location by GPS. But, it is unrealistic because of GPS module cost and large energy consumption. So, we operate localization ahead of cluster set-up phase. And Considering node density and geographic information, Cluster Heads are elected uniformly. Moreover, communication between CHs is prolonged network lifetime.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1891-1893
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• 2003

In order to development of diagnosis system for mold transformer, partial discharge measurement technique is recommended the best effective method for the evaluation of insulation condition. However, this technique was not applied to mold transformer yet. The purpose of this paper is to describe the method of partial discharge measurement for mold transformer. As we reviewed on-line test technique, sensor, transducer of pulse signal processing, set-up of test circuit for loading back device and now testing.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1892-1893
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• 2007

Because High efficiency electric vehicles use electrical energy by an power source, radiated noise at high voltage cable bring on problems at other electric/electronic components. But, in order to insure shielding effectiveness increasing braid density infinitely, it is possible that the cost is more than one third of cost of manufacturing cable. Accordingly in this paper, we studied design of cost-effective and light shield cable using dual shielding system of braid and al-foil.

• Animal Systematics, Evolution and Diversity
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• v.35 no.1
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• pp.10-14
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• 2019

Acanthochitonidae Pilsbry, 1893 is one of the chiton families characterized by 9 pairs of sutural tufts on a well-expanded girdle that overgrows plates. It is found in intertidal and subtidal zones worldwide. Of its eight genera, only two have been previously reported in South Korea: Acanthochitona Gray, 1821 and Notoplax H. Adams, 1862. Here we report Leptoplax doederleini (Thiele, 1909) as the first record of the genus Leptoplax in South Korea and describe and compare its morphological features with N. kaasi Hong, Dell'Angelo and Van Belle, 1990. In addition, we provide the partial sequence of the mitochondrial DNA cytochrome c oxidase subunit I gene as a DNA barcode sequence record.

• Journal of Species Research
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• v.6 no.spc
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• pp.26-37
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• 2017

Rotifers collected from various terrestrial and aquatic habitats such as mosses on trees or rocks, tree barks, wet mosses and wet leaf litter at streams, and dry leaf litter at four different locations in Korea, were investigated. Thirteen species belonging to nine genera in five families of monogonont and bdelloid rotifers were identified: Bryceella perpusilla Wilts, Martinez Arbizu and Ahlrichs, 2010, Collotheca ornata (Ehrenberg, 1830), Habrotrocha flava Bryce, 1915, H. pusilla (Bryce, 1893), Macrotrachela aculeata Milne, 1886, M. plicata (Bryce, 1892), Mniobia montium Murray, 1911, M. tentans Donner, 1949, Notommata cyrtopus Gosse, 1886, Philodina lepta Wulfert, 1951, P. tranquilla Wulfert, 1942, Pleuretra hystrix $Barto{\check{s}}$, 1950 and Proalinopsis caudatus (Collins, 1873). All these rotifers are new to Korea, and B. perpusilla, H. flava, M. montium, P. caudatus, P. hystrix and P. lepta are new to Asia as well. Of interest, the present study is the first to record B. perpusilla outside its type locality. In addition, P. lepta has previously been recorded from only three European countries.

• Journal of the Korean Society of Food Culture
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• v.35 no.2
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• pp.127-142
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• 2020

This research is the first known to introduce and analyze food-related content among the records left by George Clayton Foulk (1856-1893), a naval attache dispatched as part of a U.S. delegation to Korea during the Joseon dynasty in the 19th century. Sketches and memos by Foulk provide important clues in understanding the food culture during the late Joseon dynasty. By analyzing the types of foods, table composition, and intervals between serving the nine rounds of food from the rural government office, which Foulk ate during his local trip, he was able to confirm that there was a starter ('preliminary table' or 'hors d'œuvre') before the main table and that it was served before the main dish.