• Transactions of the Korean Society of Mechanical Engineers
• /
• v.13 no.3
• /
• pp.472-478
• /
• 1989

Using the SMC(sheet moulding compound) composite material consisting of E-glass chopped strand mat and unsaturated polyester resin, three-point bending tests are carried out to evaluate the elasto-plastic fracture toughness by means of R curve. The crack extension is experimentally observed with the ink staining method. The point of stable crack growth is discussed in consideration of the load-load point displacement curve, the damage behavior of the notch vicinity, and the R-curves. The damage zone of the notch vicinity was composed of the initiation and growth of subcracks as well as those of the main crack. The point of stable crack growth can be defined as the inflection point in the R curves and its point also concurrs with the proportional limit on the load-load point displacement curve.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2006.05a
• /
• pp.71-74
• /
• 2006

The purpose of this paper is to establish the common fixed point theorem in the intuitionistic fuzzy metric space in which it is a little revised in Park [11]. Our research are an extension of Jungck's common fixed point theorem [8] in the intuitionistic fuzzy metric space.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.18 no.10
• /
• pp.110-115
• /
• 2019

Stationary and rotating blades can be found in a steam turbine generator and the airfoil shapes of these blades can be defined by point data from an aerodynamic design system. The main design process of blades is composed of two steps: first, the blade surface is modeled with the point data; and then, the section data is generated which contains composite curves with line segments and arcs for CAE of the blade. The surface is modeled by a curve-net defined by the point data, which may be extended to obtain the section data to model the blade. This paper presents methods for automating the above-mentioned steps, which have been implemented in the commercial CAD/CAM system, Unigraphics, with API functions written in C-language. Finally, the proposed methods have been applied to model the blade of a steam turbine generator.

• Korean Journal of Mathematics
• /
• v.7 no.1
• /
• pp.131-138
• /
• 1999

We introduce an extended Jiang subgroup $J(f,x_0,G)$ of the fundamental group of a transformation group as a generalization of the Jiang subgroup $J(f,x_0)$ and show some properties of this extended Jiang subgroup.

• Communications of the Korean Mathematical Society
• /
• v.11 no.1
• /
• pp.1-21
• /
• 1996

In this paper the existence of spanning 3-trees in every 3-connected locally finite vertex-accumulation-point-free planer graph is verified, which is an extension of D. Barnette to infinite graphs and which improves the result of the author.

• Korean Journal of Plant Resources
• /
• v.29 no.4
• /
• pp.393-399
• /
• 2016

This study was conducted to elucidate the photosynthetic response to the environment and establish optimum cultivation conditions for the Korean endemic plant, Aster koraiensis. Photosynthetic characteristics according to growth stage, light, CO₂, and soil water potential were investigated. During the first year of transplanting, photosynthetic rates were drastically increased until June, after which they slowly declined, During the second year, photosynthetic rates declined throughout the entire growth period. The highest level of light compensation point was shown the early growth stage. Photosynthetic rates affected by intercellular CO₂ concentration were maintained or decreased over the CO₂ saturation point. The lowest CO₂ compensation point was 16.1 μmol·mol⁻¹ during March. The morphological changes of leaves were observed due to shading with chlorophyll contents increasing. Photosynthetic rates were higher at 0% and 50% shading treatments than at 75%. There were rarely any morphological changes of leaves due to soil moisture, however, changes to leaf compactness were observed. Photosynthetic rate, apparent quantum yield, and respiration rate increased, whereas water use efficiency decreased over −25 kPa of soil moisture.

• Journal of Agricultural Extension & Community Development
• /
• v.7 no.2
• /
• pp.333-345
• /
• 2000

The objectives of this study were to review various aspects of society on Genetically Modified Organism(GMO) in the view point of environmental sociology. There were many assertions related to GMO, and application of biotechnology. Some people assert GMO as harmful to human health, and some people as not harmful, however, there were no proven evidences to report. Through the literature review, this study intended; 1) to identify the present condition of GMO, 2) to weigh the pros against cons of views on GMO, 3) to study an aspect of society on GMO, and 4) to assert its necessity to mark GMO or not, because citizens have a rights to know natural or GMO. Based on the conclusions of this study, following recommendations were offered: 1) To review continually the GMO in the view point of environmental sociology especially in the areas of food safety, biosafety, trade, and public research investment, and 2) further detailed studies of GMO may necessary to ensure safety to human health and environment.

• Physical Therapy Korea
• /
• v.16 no.4
• /
• pp.1-7
• /
• 2009

The active-knee-extension (AKE) test has been used to measure hamstring muscle length. The traditional AKE test measures the popliteal angle to the point of resistance with a 90-degree flexion of the hip fixed by straps, while the stabilized AKE test measures the popliteal angle to the point of resistance with a 90-degree flexion of the hip stabilized using a pressure biofeedback unit providing lumbopelvic stabilization. The purpose of this study was to determine test-retest reliability of the traditional AKE test and stabilized AKE test. Twenty healthy adults participated in the study. The popliteal angles were measured with a digital inclinometer during each test. To assess the test-retest reliability between the 2 test sessions, intraclass correlation coefficients (ICCs) were calculated. The intrasubject coefficient of variation ($CV_{intra}$) was also calculated. To compare the traditional and stabilized AKE tests for changes in pressure, paired t-tests were applied. The results of this study were as follows: 1) ICCs(3,1) value for test-retest reliability was .96 in the traditional AKE test, and was .98 in the stabilized AKE test. 2) The maximal $CV_{intra}$ was 33.7% in the traditional AKE test and 15.7% in the stabilized AKE test. 3) Differences of $6.1{\pm}2.1$ mmHg in pressure were measured in the traditional AKE test, and differences of $1.2{\pm}1.0$ mmHg in pressure were measured in the stabilized AKE test. The results show the traditional and stabilized AKE test to be highly reliable, with test-retest reliability. However, the stabilized AKE test represented less variation and more stabilization than the traditional AKE test. Further study is needed to measure the inter-rater reliability of the stabilized AKE test for generalization and clinical application.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.9 no.2
• /
• pp.141-147
• /
• 2016

NHPP software reliability models for failure analysis can have, in the literature, exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, infinite failures NHPP models that repairing software failure point in time reflects the situation, was presented for comparing property. Commonly used in the field of software reliability based on Flexible Weibull extension distribution software reliability of infinite failures was presented for comparison problem. The result is that a relatively small shaping parameter was effectively. The parameters estimation using maximum likelihood estimation was conducted and model selection was performed using the mean square error and the coefficient of determination.. In this research, software developers to identify software failure property follows shape parameter, some extent be able to help is considered.

• Journal of Korea Multimedia Society
• /
• v.11 no.3
• /
• pp.292-300
• /
• 2008

An algorithm for detecting a line segment in an image is presented using incremental pixel extension. We use a different approach from conventional algorithms, such as the Hough transform approach and the line segment grouping approach. The Canny edge is calculated and an arbitrary point is selected among the edge elements. After the arbitrary point is selected, a base line approximating the line segment is calculated and edge pixels within an arbitrary radius are selected. A weighted value is assigned to each edge pixel, which is selected by using the error of the distance and the direction between the pixel and the base line. A line segment is extracted by Jilting a line using the weighted least square method after determining whether selected pixels are linked or delinked using the sum comparison of the weights. The proposed algorithm is compared with two other methods and results show that our algorithm is faster and can detect the real line segment.