• Research in Mathematical Education
• /
• v.11 no.3
• /
• pp.197-207
• /
• 2007

Based on a survey on 1620 students in primary school and secondary school., by adopting Eysenck Personality Questionnaire (EPQ), we got the following findings : 1. There is close relationship between emotionality characteristics of temperament and mathematics academic achievement of the subjects at Grade 5 (Primary 5), Grade 8 (Junior Secondary 2), and Grade 10 (Senior Secondary 2). Also there is close relationship between internal-external directivity characteristics of temperament and mathematics academic achievement at Grade 5 and Grade 8. While there is not close relationship between internal-external directivity characteristics of temperament and mathematics academic achievement at Grade 10; 2. There is close relationship between temperament types and mathematics academic achievement of the subjects from the three grades. Superior temperament, which benefit learning mathematics, are sanguine, sanguine-phlegmatic and phlegmatic; While inferior temperament types, which don't benefit learning mathematics, are choleric, melancholic and choleric-melancholic. With the rising of grade, temperament types of benefiting learning mathematics converts from external directivity emotion balance to balance of internal-external directivity emotion stability. While temperament of no benefiting learning mathematics converts from internal directivity emotion balance to balance of internal-external directivity emotion instability; 3. In mathematics education, students' temperament difference, which affects learning mathematics, should be recognized. Mathematics teachers should find out the best teaching ways, forms and methods which are suitable for student's temperament type, so that the students with different temperament types can gain better mathematics academic achievement.

• The Journal of Internal Korean Medicine
• /
• v.33 no.4
• /
• pp.558-571
• /
• 2012

Objectives : The purpose of this study was to verify the difference in diet, digestion, sweat, feces and urination characteristics according to body shape characteristic. Methods : 1,302 participants were divided into 4 body types and were assessed through the questionnaire about Sasang constitution's ordinary symptoms such as diet, digestion, sweat, feces and urination characteristics. Results : Hyeong-keum type had active characteristics in the size of their meal and speed of taking meal. Hyeong-keum type got the most in the amount of sweating. And Yo-wi type reported the greatest urinary frequency. Conclusions : The difference of body type influences Sasang constitution's ordinary symptoms such as diet, sweat and urination. In digestion and feces, there was no statistical significance in the difference.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1996.04a
• /
• pp.97-101
• /
• 1996

In this paper, We have studied internal quality incluiding chemical compositions, microscopic structrue and nonmetalic inclusion of test materials. We have analyzed dynamic characteristics of cutting resistence including tensile strength value, hardeness value, impact value etcs. We have compared chip treatments of test materials. In analyzing internal quality, all of test materials have typical ferrite+pearlite structure. But, nonmetallic inclusion have oxide and sulfide inclusion in medium carbon steels, mainly sulfide inclusion is existed in S-free cutting steels. In Ca+S-free cutting steels, calcium aluminate and sulfide complex inclusion, had low-melting points, as deformation of sulfide and oxide inclusion is existed. machining characteristics, cutting resistence is maximum in Ca+S-free cutting steels, minimum in medium carbon steels. Chip treatements are excellent in S-free cutting steels, similar to the Ca+S free cutting steels and medium carbon steels.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.58 no.4
• /
• pp.557-562
• /
• 2009

Recently, researchers are developing a new, clean, renewable and sustainable energy to the industrial areas and the residential areas. Solar cell and fuel cell energy are presented in this paper. The paper shows the P-I and I-V characteristics of fuel cells which are connected in parallel and series. And the voltage drop of internal resistance of the fuel cell decreases with the increasing of the current of the fuel cell. A voltage drop at the internal resistance is increased according to the current, thus the terminal voltage is decreased. The internal resistance is calculated $0.3[\Omega]$ from maximum power transfer condition.

• Journal of ILASS-Korea
• /
• v.11 no.2
• /
• pp.113-120
• /
• 2006

The effect of internal liquid flow on spray plume characteristics was performed experimentally in subsonic cross flows. The injector internal flow was classified as three modes such as a normal, cavitation, and hydraulic flip. The objectives of the research are to investigate the effect of internal liquid flow on the spray plume characteristics and compare the trajectory of spray plume with previous works. The results suggest that the trajectory and width of spray plume can be correlated as a function of liquid/air momentum flux ratio(q), injector diameter and normalized distance from the injector exit(x/d). It's also found that the injector internal turbulence influences the spray plume characteristics significantly.

• Proceedings of the KSRS Conference
• /
• 2004.10a
• /
• pp.689-692
• /
• 2004

Hydrographic data obtained from several ship experiments have shown that internal waves are frequently observed in the East (Japan) Sea, mostly in the continental slopes located along the western side of the East Sea. It is well known that oceanic internal waves can be detected well in synthetic aperture radar (SAR) images. Interactions between surface capillary-gravity waves and horizontally varying surface currents induced by internal waves produce variations in sea surface roughness which can be detected by SAR. C-band SAR images from ERS, ENVISAT ASAR and RADARSAT have been used to study the characteristics of internal waves in the East Sea. The observed properties of internal waves from many SAR images were compared and verified from in-situ measurements and theories.

• Wind and Structures
• /
• v.29 no.4
• /
• pp.235-246
• /
• 2019

Wind loading is one of important loadings that should be considered in the design of large hyperbolic natural-draught cooling towers. Both external and internal surfaces of cooling tower are under the action of wind loading for cooling circulating water. In the previous studies, the wind loads on the external surface attracted concernedly attention, while the study on the internal surface was relatively ware. In the present study, the wind pressure on the internal surface of a 220 m high cooling tower is measured through wind tunnel testing, and the effect of ventilation rate of the packing layer on internal pressure is a major concern. The characteristics of internal wind pressure distribution and its effect on wind-induced responses calculated by finite element method are investigated. The results indicate that the wind loading on internal surface of the cooling tower behaves remarkable three-dimensional effect, and the pressure coefficient varies along both of height and circumferential directions. The non-uniformity is particularly strong during the construction stage. Analysis results of the effect of internal pressure on wind-induced responses show that the size and distribution characteristics of internal pressure will have some influence on wind-induced response, however, the outer pressure plays a dominant role in the wind-induced response of cooling tower, and the contribution of internal pressure to the response is small.

• Korean Journal of Food Science and Technology
• /
• v.31 no.5
• /
• pp.1295-1299
• /
• 1999

This study was conducted to develop a index for the judgment of suitability of storage conditions by internal gas concentration of 'Fuji' apples under CA storage, and was examined the relationship between the levels of quality characteristics(flesh firmness, titratable acidity and surface green color) and the infernal ethylene and carbon dioxide concentrations of apples. The levels of quality characteristics were not decreased for terms of storage when the infernal ethylene concentration of apples was below 10 ppm, but the levels of quality characteristics were sharply decreased when it was above 10 ppm of Internal ethylene. The high levels of quality characteristics were maintained by the lower internal carbon dioxide concentration of apples, especially at below 2% of internal carbon dioxide. These result showed that the suitable condition for CA storage of 'Fuji' apples was a condition for having below 10 ppm of internal ethylene and below 2% of internal carbon dioxide in apples. The internal ethylene and carbon dioxide concentrations of apples during CA storage can be used as a crucial index for the suitability judgment of storage conditions.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.39 no.3
• /
• pp.117-131
• /
• 2014

As interests in the management of government-owned corporation rise, in these days, debt reduction and normalization of management of those companies have been proceeding under the lead of government. At this point, it is very important to seek internal marketing method for improvement of internal employees' satisfaction, loyalty and organization performance. This study analyzes impact of factors of internal marketing effect on organization satisfaction, loyalty and organization performance in the context of the domestic public companies, the Korea Electric Power Corporation (KEPCO) and the Korea Water Resources Corporation (K-WATER)'s employees empirically. There are some significant differences between the two publics. It is proved that delegation of the authority influences on internal satisfaction and organization performance in the case of KEPCO, and education and training influence on internal satisfaction and organization performance in the case of K-WATER. On the other hand, in the case of K-WATER, any internal marketing factors don't influence on loyalty. The results of this study show somewhat different characteristics depending on the characteristics of firm, however, it is expected that this study can be very useful in regards to similar public enterprises or businesses.

• The KSFM Journal of Fluid Machinery
• /
• v.11 no.2
• /
• pp.13-19
• /
• 2008

Butterfly valves are widely used as control valves for industrial process. For the definition of optimum configuration of the valve, wide range of related studies has been actively conducted in the case of working fluids of water or air under the normal temperature. Recently, internal flow and performance characteristics of cryogenic butterfly valve for LNG carrier take a growing interest in the field of research and development. Therefore, present study is aimed to investigate the internal flow and performance characteristics of the cryogenic butterfly valve because the study result for the valve can be hardly found at present. Part 1 of this paper describes the study result of a butterfly valve model under the condition of the normal temperature. Succeeding Part 2 of this paper will describe the internal flow characteristics of a cryogenic butterfly valve for LNG carrier. The results of Part 1 show that pressure loss coefficients and flow rate coefficients obtained by the present experiment and CFD analysis agree well each other. Moreover, internal flow visualization for the valve by CFD analysis and PIV measurement have revealed complicated flow patterns of the internal flow field in detail.