• Journal of the Korean association of regional geographers
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• v.3 no.1
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• pp.165-182
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• 1997

The aim of this paper is to clarify geomorphic features on talus within ${\check{O}}rumkol$ and the origin of ${\check{O}}rumkol$. ${\check{O}}rumkol$ is located in Milyang of Kyungnam province, in South Korea. ${\check{O}}rumkol$ is good area to study talus. because it is characterized by following three geomorphic landscapes : free face surrounding ${\check{O}}rumkol$ ; ${\check{O}}rumkol$ with deep and wide valley floor ; lots of taluses typically developing within ${\check{O}}rumkol$. The main results can be summarized as follows: 1) The origin of ${\check{O}}rumkol$ may be suggested two assumptions : one is that its origin have been resulted from intrusion structure(intrusive rock might capture less resistant rock as tuff) ; the other is that its origin have been resulted from volcanic depression after intrusion or eruption. But these assumptions are not obvious. therefore more geological evidences will be supplemented after this 2) The characteristics of ${\check{O}}rumkol$ talus (1) Pattern ${\check{O}}rumkol$ taluses are tongue-shaped or cone-shaped in appearance. They are $50{\sim}200m$ in length and the range of the maximum width from 25 to 115m and one of their mean slope gradient from 32 to $36^{\circ}$ (2) Origin ${\check{O}}rumkol$ taluses have been formed under periglacial environment in the last glacial age and they are classified into rock fall talus type, considering in conjunction with the shape, hardness, sorting, weathering conditions of constituent debris. (3) The stage of landform development ${\check{O}}rumkol$ talus slope profiles are mainly concave slope. This concave slope type was eventually caused by talus creep at the lower end of the talus. That means new additions of debris from the free face have virtually ceased and there is no evidence of recent motion in the deposit. Now it is predominant that vegetation cover is gradually increasingly. Therefore ${\check{O}}rumkol$ taluses appear to be relict form stage. at present.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.611-619
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• 2007

This study was carried out to analyze the landslide characteristics and forest environment factors on the landslide area of 7 national parks in korea. The results obtained from this study were summarized as follows; The total number of landslide occurrence was 44 areas. The average length of the landslides scar was 152 m, average width was 17 m. And the average area was $2,818m^2$. The factors influencing landslides were highly occurred in Metamorphic rock, mixed forest type. And also, $30{\sim}35^{\circ}$ in slope gradient, NE in slope aspect, slope higher than 1,000 m, concave (凹) type in vertical and cross slope, 0 ordered stream. The main factors affecting landslide area in stepwise regression analysis were sheet type in landslided shape, NE in slope aspect, 2 ordered stream, SE in slope aspect, slope gradient and complex slope in cross slope type in order of regression coefficient.

• Journal of The Geomorphological Association of Korea
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• v.25 no.2
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• pp.1-14
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• 2018

The main objective of this paper is to classify properties of the locational environment for each debris type by calculating likelihood ratio based on the correlation between the distributions for each type of debris landform. A total of 8 thematic maps, like as elevation, slope, aspect, curvature, topographic wetness index (TWI), soil drainage, geology, and landcover including with GIS spatial information generally used in this type of debris landform analysis. The results of this study showed that the block stream had a high likelihood ratio compared to talus in areas with relatively high elevation; and concerning slope, the block stream had a high likelihood ratio in a relatively low region than talus. Concerning aspect, a clear correlation could not be analyzed for each debristype, and concerning curvature, the block stream displayed a developed slope on the more concave valley than the talus. Analysis concerning TWI, the block stream displayed a higher likelihood ratio in wider sections than talus, and concerning soil drainage, the talus and block stream both displayed a high likelihood ratio in regions with well-drained soil. The talus displayed a high likelihood ratio in the order of metamorphic rocks, sedimentary rocks, and granite, while the block stream displayed a high likelihood ratio in the order of volcanic rocks, granite, and sedimentary rocks. In addition, concerning landcover, the likelihood ratio had the most concentrated distributed compared to natural bare land only concerning talus. Based on the likelihood ratio result, it can be used as basic data for extracting the possible areas of distribution for each debris type through the GIS spatial integration method.

• Journal of Welding and Joining
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• v.29 no.3
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• pp.51-57
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• 2011

Bead shape control with gas force process has been developed to overcome the concave back bead in pipe orbital welding. However, It is impossible to make a convex back bead using the existing gas nozzle, because it has high gas-consuming and low gas force. The purpose of this paper, to develop optimum shape of nozzle which to reduce the consumption of gas, maximizing the shield gas force with low cost and high productivity coincide the Green welding. In this paper venturi-type nozzle was designed by using the Venturi meter and compared velocity, pressure, arc shape in the flat position with existing CP-nozzle. As a result, Venturi-type nozzle's maximum velocity and pressure was improved at the same flow rate. Also heat input was increased by the arc contraction in the flat position.

• Journal of the Korean housing association
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• v.22 no.6
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• pp.51-60
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• 2011

The maintenance cost depends on various factors such as building volume, floor area, number of household and so on. The maintenance cost of the apartment housing is affected by the maintenance type, building physical factor, sociogeographic aspects. Among these, the maintenance characteristics is represented and made up by the total floor area and number of household which means main factor to provide the building scale roughly. In this paper, it aimed at modelling the estimation function of the maintenance cost with the total floor area and number of household and analyzing the elasticity of the two factors. Although items of maintenance cost are various in general cost, repair cost and so on, we classified these items into the 5 categories. 5 categories are a general cost, a facility maintenance cost, a utilization cost, insurance and sanitary cost. The estimation function used a power function and it has better goodness-offitness than any other estimation methods in statistics. A power function has a three curve types with concave and convex and linear style to the origin.

• Journal of The Korean Astronomical Society
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• v.44 no.2
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• pp.49-58
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• 2011

We calculate the energy spectra of cosmic ray (CR) protons and electrons at a plane shock with quasi-parallel magnetic fields, using time-dependent, diffusive shock acceleration (DSA) simulations, including energy losses via synchrotron emission and Inverse Compton (IC) scattering. A thermal leakage injection model and a Bohm type diffusion coefficient are adopted. The electron spectrum at the shock becomes steady after the DSA energy gains balance the synchrotron/IC losses, and it cuts off at the equilibrium momentum $p_{eq}$. In the postshock region the cutoff momentum of the electron spectrum decreases with the distance from the shock due to the energy losses and the thickness of the spatial distribution of electrons scales as $p^{-1}$. Thus the slope of the downstream integrated spectrum steepens by one power of p for $p_{br}$ < p < $p_{eq}$, where the break momentum decreases with the shock age as $p_{br}\;{\infty}\;t^{-1}$. In a CR modified shock, both the proton and electron spectrum exhibit a concave curvature and deviate from the canonical test-particle power-law, and the upstream integrated electron spectrum could dominate over the downstream integrated spectrum near the cutoff momentum. Thus the spectral shape near the cutoff of X-ray synchrotron emission could reveal a signature of nonlinear DSA.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.1
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• pp.31-40
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• 1992

This paper presents an automatic feature recognition system for recognizing and extracting feature information needed for the process planning input from a 3D CAD system. A given part is modeled by using the AutoCAD and feature information is automatically extracted from the AutoCAD database. The type of parts considered in this study is prismatic parts composed of faces perpendicular to the X, Y, Z axes and the types of features recognized by the proposed system are through steps, blind steps, through slots, blind slots, and pockets. Features are recognized by using the concept of convex points and concave points. Case studies are implemented to evaluate feasibilities of the function of the proposed system. The developed system is programmed by using Turbo Pascal on the IBM PC/AT on which the AutoCAD and the proposed system are implemented.

• Journal of the Korean Institute of Rural Architecture
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• v.4 no.1
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• pp.45-60
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• 2002

This research is the second attempt to illustrate the phases of ancient Korean architecture through a comparative study of historical materials such as historical ruins, relics, stone remains and art products. Among these the stone stupa (budo), contains many architectural aspects of old times, which give clues to trace the characteristics of the antient Korean structures. The study brings about following results: 1. The pillar employs an entasis technique, and the bracket system (gongpo) consists of cross beams (changbang) and small supporting blocks (soro) thereupon. A type of the bracket arm (chomcha) is also found on top of the pillar. 2. Windows and doors are assumed from the carved features on the stone stupa to be pair-doors which could be folded twice sideways and upwards. 3. There are two types of eaves; the single eaves and the double eaves consisting of a rafter and a flying rafter. 4. The roof has furrows formed by the concave tiles and the convex ones and also the tiles at the edge of eaves. And there are evidences that a variety of small images of animal and human figures were decorated along on top of the eaves.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.11
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• pp.1259-1264
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• 2011

This paper suggests a new film-type haptic actuator based on cellulose acetate electro-active paper. Conventional tiny haptic actuators in mobile devices can create vibrotactile sensation at only near resonant frequency. The strategy of operating near the resonant frequency, however, brought a new issue for creating vibrotactile sensation which can be strong enough to feel in arbitrary frequency. Another problem is that the size of the conventional actuator is not small enough to be embedded into slim mobile devices. In order to achieve these issues, we propose a thin and tiny actuator based on a cellulose acetate material charged with an electric potential. The motion of the actuator can be a concave or a convex by controlling a polarity of both charged membranes and the actuator performance can be modulated by increasing level of biased electric potential.

• Journal of Chest Surgery
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• v.49 no.3
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• pp.214-217
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• 2016

Pectus arcuatum is a rare complex chest wall deformity. A 31-year-old female presented with a severely protruding upper sternum combined with a concave lower sternum. We planned a modified Ravitch-type operation. Through vertical mid-sternal incision, chondrectomies were performed from the second to fifth costal cartilages, saving the perichondrium. Horizontal osteotomy was performed in a wedge shape on the most protruding point, and followed by an additional partial osteotomy at the most concaved point. The harvested wedge-shape bone fragments were minced and re-implanted to the latter osteotomy site. The osteotomized sternum was fixed with multiple wirings. With chondrosternoplasty, a complex chest wall deformity can be corrected successfully.