• The Korean Journal of Ecology
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• v.21 no.3
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• pp.243-249
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• 1998

Radicoid structure of herbaceous communities in Mt. Kumbyung, Chunchon, Kangwon-Do was clarified emphasizing on the dominance of clonal plants in relation to vegetation development. In the total vegetation, 46% species identified were rhizomatous, 26% were species with tap roots, and 13% were stoloniferous species. Thus, all clonal species, including plants with bulb, corm and tuber, covered 62.8% of the total species. in the understory of Quercus, Pinus and Larix forests, 68.2% were clonal, which means 5% more compare to total vegetaion. Dominance of clonal plants became more conspicuous as their importance value was calculated. That is, they covered average 86% for the following three communities: 85% in Quercus, 95% in Pinus, and 76% in Larix, Especially, the rhizomatous plants were remarkable. Overall, clonal species dominated over the other radicoid types in terms of not only the number of species, but also the importance value. Dominance of these species was more peculiar in understory of forests, indicating the occupancy of clonal plants was related to the vegetation development.

• Journal of the Korean Home Economics Association
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• v.39 no.7
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• pp.71-84
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• 2001

The purpose of this study was to investigate the development of preschoolers'narrative competence. The subject were 60 preschoolers aged 3 through 5 years who were enrolled in the day care center All the subjects were asked to produce a new story. All the story children toad were recorded on audiotape. The data were analyzed Qualitatively and quantitatively using content analysis and the statistical package for Social Science 9.0. The main results of this study were as follows. 1) Significant age difference was observed in preschooler's narrative structure. Older children produced structurally more complex stories containing setting, character, initiating event, attempt and consequence than younger children. 2) Significant age difference was observed in preschooler's narrative length. Older children used significantly more words and sentence when they produced stories than younger children.3) Preschooler'narrative structure was significantly correlated with narrative length.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.7
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• pp.679-685
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• 2006

In this paper, development of an omni-directional mobile robot with rocker-bogie link structure is addressed. The overall mobile robot system consists of the robot mechanism with embedded control architecture, wireless communication with host graphic monitoring system, and the joy stick tole-controller. In the cluttered environment with various sizes of obstacles, the omni-directionality and the traversality are required for a mobile robot, so that the robot call go around or climb over the obstacles according to the size. The mobile robot mechanism developed in this paper has both of the omni-directionality and the traversality by 4 steerable driving wheels and the 2 additional passive omni-directional wheels linked with the rocker-bogie structure. The kinematic modeling for the mobile robot is described based on the well-known Sheth-Uicker convention and the instantaneous coordinate system.

• Journal of the Korean earth science society
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• v.30 no.5
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• pp.550-564
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• 2009

When magnetotelluric (MT) data are obtained in the vicinity of the coast, the surrounding seas make it difficult to interpret subsurface structure, especially the deep part of the subsurface. We introduce an iterative method to correct the sea effect, based on the previous topographic correction method that removes the distortion due to topographic changes in seafloor MT data. The method first corrects the sea effect in observed MT impedance, and then inverts corrected response in a model space without the sea. Due to mutual coupling between the sea and the subsurface structure, the correction and inversion steps are iterated until the changes in each result become negligible. The method is tested for 1- and 2-D structures using synthetic MT data produced by 3-D forward modeling including surrounding seas. In all cases, the method closely recovers the true structure assumed to generate synthetic responses after a few iterations.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.04a
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• pp.10-17
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• 2001

With the introduction of durability examination into design code of concrete structure, a prediction of early-age behavior of concrete and its cracking resistance becomes very important. But, the early-age behaviors such as hydration, micro-structure development, moisture transport and mechanical properties development is quite complicated and coupled each other, and thus those can not be solved independently. One way to analyze those is to model their behaviors analytically and solve those computationally within a unified framework. In this paper, we propose a finite element technique to predict the early-age behaviors of concrete within the unified framework. The technique is applied to evaluatio of cracking in a massive concrete structure and then the analysis results are discussed.

• Journal of architectural history
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• v.7 no.2 s.15
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• pp.91-112
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• 1998

There remain several archiectural drawings which was made in Chosun dynasty, which are quite different from current drawings. The site plan which is composed of slanted elevations doesn't exhist in Western drawing method. This elevation development method is common in Korea, China, and Japan. These three nations also have a common point which the wooden structure are popular. So elevation development method is reasonable to represent the wooden structure. Because a drawing mehod reflects cultural character and thought, it is important to read the architectural perception at that time. In this viewpoint, I studied the characters of the drawing method in Chosun dynasty according to the peoriodical articulation of century, and how the drawing method reflects the thought at that time. And I suggested a new posibility of effective and reasonable drawing method for the wooden structure.

• IE interfaces
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• v.19 no.4
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• pp.281-290
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• 2006

The main objective of this study is to analyze the structure of efficiency of R&D input variables and the attributes of patent information as output of R&D activities in the major manufacturing industries (electric & electronics, machinery, chemical, textile) from the mid-1970s to the late-1990s by the development of "mapping technique". To attain this objective we first have examined the attribute of time-lag which depends on the absolute, and the cumulative values between input and output. And on the basis of this result, we have made an analysis on the impact to extract the main variables affecting patent by industries. Moreover, according to time trend of the impact variables, we have analyzed the structure of R&D efficiency, and of technological progress which will be changed with time by patent information. It has been aimed at constructing technological progress patterns in the Korea industry.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.646-647
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• 2007

The topology processor uses the status of circuit breakers as input. It operates on the bus section connectivity data, which is stored in the data base, to determine the bus/branch topology of the network. This output of the topology processor forms part of the input to the state estimation or dispatcher power flow. This paper describes the development of the topology processor using matrix structure.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1261-1263
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• 2005

The micro permanent magnet(PM) type stewing motor preferred solution for many small electronics position determination devices since it is small in size. Thus, there are growing demands for PM type stepping motor that greater mechanical output, smaller size. But, the design of the it, having high performance and small size is very difficult because of its complex mechanical structure. This paper deals with a development of the newly structured micro PM type stepping motor with claw-poles. We introduced the small-sized PM type stepping motor that has new structure and analyzed the magnetic characteristic of it versus general type model using 3-D finite element analysis(FEA).

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.4
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• pp.452-459
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• 2019

In order to design and manufacture structures such as a guided missile, assembly process with fastener is an essential method of fabrication. In this study, the dynamic characteristics of a cylindrical structure with bolted joints were studied using experimental methods. The change of the natural frequency of the structure with the change of the fastening method and the tightening torque were measured by the test and the finite element analysis was performed using the stiffness model of the fastening part according to the fastening method and compared with the test results.