• Journal of the Korean Geotechnical Society
• /
• v.36 no.7
• /
• pp.5-14
• /
• 2020

Kansai International Airport (KIX) was opened in September 1994. Although 26 years have passed since the completion of the first island, long-term settlement is still in progress. This settlement occurs in the Pleistocene layer. For it is not easy to determine the permeability of the Pleistocene sand layer because the thickness and the degree of fine content in the horizontal direction are constantly changing. In addition, it is also a difficult to predict the interactive behavior of the ground due to the construction of the second phase island adjacent to it. In order to solve this problem, a two-dimensional finite element analysis considering elasto-viscoplastic was performed to evaluate the long-term deformation, including the interactive behavior of the alternating Pleistocene foundation due to the construction of two adjacent reclaimed islands. In general, two-dimensional analysis can be used when a section can represent the entire sections. However, Kansai Airport is an artificial reclaimed island so two-dimensional analysis cannot solve the problem such as the stress deformation in the corners of the island. Additionally, the structure of the actual sub-ground through physical exploration is non-homogeneity and its thickness is also not constant. Therefore, there are limitations for the two-dimensional analysis to explain the phenomena. That is, three-dimensional analysis is strongly required. Due to these demands, the author extended the existing two-dimensional program capable of elasto-viscoplastic analysis to three-dimensional and completed the verification of the three-dimensional program developed through one-dimensional consolidation analysis. In order to demonstrate the validity of the developed 3D program that has been verified, an analysis is performed under the same analysis conditions as the existing research using a two-dimensional program. The effectiveness of the developed 3D numerical analysis program was demonstrated by comparing the analysis results with the 2D results and actual measurement data.

• Convergence Security Journal
• /
• v.17 no.2
• /
• pp.173-183
• /
• 2017

This study is for presenting the factors about success attribution that fit the korean security service conditions and developing the actual analysis of measurement tools by investigating the success factors of the security service agents. To this end, conducted a meeting from the fully open questionnaire at first, and then formed the semi-structured questionnaire, finally carried out the survey from the closed questionnaire and analyzed data from SPSS 21.0, AMOS 21.0 and developed the measurements. It was conducted from December, 2014 to June, 2015. This survey was conducted of 170 security guards after the verification of the content validity though the pilot survey and presented the success attribution factors and standards on the basis of the result form this survey. At the first and second analysis process, the success attribution factors of the guards consisted of inner qualities, external qualities, induction factors for inner qualities, and induction factor for external qualities. On analysis of the final data and documents, however, at the third analysis, the success attribution factors of the guards consisted of 'martial arts and physical ability'(4 questions), 'attitudes to work'(3 questions), 'support for the working environment'(3 questions), 'organized business skills'(3 questions), 'attitudes to the duty'(3 questions), and 'coping with crises(2 questions).

• Journal of the Korea Convergence Society
• /
• v.11 no.5
• /
• pp.43-49
• /
• 2020

The purpose of this study was to determine whether PNF respiratory exercise increases the vital capacity and maximal voluntary volume of 20s normal adults by 45° leaning sitting position. Twenty normal adults in their 20s were randomly assigned to an experimental group and control group. Over the course of four weeks, the experimental group participated in PNF respiration exercises by 45° leaning position for 30 minutes three per week. And the control group participated in diaphragm respiration exercises by 45° leaning position for 30 minutes three times per week. Subjects were assessed post-test by measurement of vital capacity, maximal voluntary volume. Our findings show that the experimental group had significant improvements in vital capacity, maximal voluntary volume(p<.05). In this study, the experimental group showed more improvement in pulmonary function, which indicates that the PNF respiratory exercise by 45° leaning sitting position is effective at increasing the pulmonary function of normal adults.

• Journal of the Korean Data and Information Science Society
• /
• v.25 no.3
• /
• pp.567-578
• /
• 2014

PEAS (performance enhancement attitude scale) has been used to measure attitude and disposition toward doping in elite athlete. It is constructed of 17-item, 6-point scale. The purpose of this study was to verify validity of the PEAS for Korean elite player through Rasch model. The scale was administered to 438 Korean elite players. Principal component analysis was used to verify unidimensionality using SPSS program. Rasch measurement computer program, WISTEPS, was used to estimate goodness-of-fit of items and category structure. Differenctial item functioning by gender was also estimated by the WINSTEPS program. All alpha level was set at 0.05. First, principal component analysis showed that unidimensionality is satisfied as over 20.0% of variance of eigenvalue. Second, category probabilities curve showed 5-point scale was better than 6-point scaled statistically. Third, seven items (1, 9, 10, 12, 13, 14, 17) in the 17-item were not good model fit and three items (3, 12, 13) were estimated as the differential item functioning. This study showed that 9-item, 5-point scale is better PEAS to Korean elite player.

• Journal of the Microelectronics and Packaging Society
• /
• v.9 no.4
• /
• pp.11-16
• /
• 2002

In this study, the dry etching characteristics of $SrBi_2Ta_2O_9$ (SBT) thin films were investigated by using ICP-RIE (inductively coupled plasma-reactive ion etching). The etching damage and degradation were analyzed with XPS (X-ray photoelectron spectroscopy) and C-V (Capacitance-Voltage) measurement. The etching rate increased with increasing the ICP power and the capacitively coupled plasma (CCP) power. The etch rate of 900$\AA$/min was obtained with 700 W of ICP power and 200 W of CCP power. The main problem of dry etching is the degradation of the ferroelectric material. The damage-free etching characteristics were obtained with the $Ar/C1_2/CHF_3$ gas mixture of 20/14/2 when the ICP power and CCP power were biased at 700 W and 200 W, respectively. The experimental results show that the dry etching process with ICP-RIE is applicable to the fabrication of the single transistor type ferroelectric memory device.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.17 no.1
• /
• pp.10-16
• /
• 2003

The purpose of this study was to investigate the scope of standard color perception for Americans and to compare the differences in color perception between Korean and American undergraduates. Sixty male and fifty-one female American undergraduates were selected as a random sample. Color perception was tested with the naked eyes. Minolta Chroma Meter CR 300 was used for physical measurement of the color. Based on the objective of this study and the data generated the following results were drawn: 1) We found no distinctive difference in color perception by different eye colors. 2) Color perception of American undergraduates is largely classified into four different groups: simple group includes Yellow, Green, Blue, White, Gray, and Black, X(-axis)group includes Yellow Red, Y(-axis)group includes Blue Green, Purple, complex group includes Yellow Red, Purple Blue. 3) The differences in color perception between the two undergraduate groups were found to be significant with four colors: Yellow Red, Green, Blue, and Purple. 4) There is a wide difference between the values of standard color and inn percept color. When undergraduates in both countries were compared, it turned out that Korean students were more accurate than Americans in color perception. 5) American students perceived Red, Yellow, and Green colors relatively correctly, but showed an extremely low degree of accuracy in Blue and Purple Blue color perception.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.1
• /
• pp.474-484
• /
• 2016

This study was performed to identify the effects of the improvement of brain function by CST on the elderly with the 2nd or 3rd grade of long-term care insurance service. A quasi-experimental design using a nonequivalent control group, pre-post test was used. A total of 12 elders (6 in the experimental group and 6 in the control group) were recruited. Upledger CST(10-Step Protocol) was performed on each subject for 50 minutes per session, once a week, for a total of 8 treatments over an 8 week period from Jan to Feb 2015. The brain function quotient was measured before the 1st CST and after the last CST by portable EEG measurement device using a 2 Channel neuro-feedback system. The data was analyzed by SPSS (Ver. 18.0) program. After CST intervention, the attention quotient (AQ), level of tension, anti-stress quotient (ASQ), emotion quotient (EQ) and brain quotient (BQ) of the experimental group was significantly better than that of the control group. These results showed that the CST was effective in reducing the level of fatigue by the AQ, increasing the physical and psychological stress relief by the ASQ, emotional balance by the EQ, and improving the total brain function by the BQ. Therefore, CST can be used as an effective intervention for improving the health and brain function of the elderly in health facilities.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2003.10a
• /
• pp.134-135
• /
• 2003

The dental implant materials required good mechanical properties, such as fatigue strength, combined with a high resistance to corrosion. For increasing fatigue resistance and delaying onset of stress corrosion cracking, shot peening has been used for > 50 years to extend service life of metal components. However, there is no information on the electrochemical behavior of shot peened and hydroxyapatite(HA) coated Ti-6Al-4V alloys. To increase fatigue strength, good corrosion resistance, and biocompatibility, the electrochemical characteristics of Ti/TiN/HA coated and shot peened Ti-6Al-4V alloys by electron beam physical vapor deposition(EB-PVD) have been researched by various electrochemical method in 0.9%NaCl. Ti-6Al-4V alloys were prepared under the condition of hydrogen and vacuum arc furnace. The produced materials were quenched at 1000$^{\circ}C$ under high purity dried Ar atmosphere and were hold at 500$^{\circ}C$ for 2 hrs to achieve the fatigue strength(1140㎫) of materials. Ti-6Al-4V alloys were prepared under the condition of hydrogen and vacuum arc furnace. Shot peening(SP) and sand blasting treatment was carried out for 1, 5, and 10min. On the surface of Ti-6Al-4V alloys using the steel balls of 0.5mm and alumina sand of 40$\mu\textrm{m}$ size. Ti/TiN/HA multilayer coatings were carried out by using electron-beam deposition method(EB-PVD) as shown Fig. 1. Bulk Ti, powder TiN and hydroxyapatite were used as the source of the deposition materials. Electrons were accelerated by high voltage of 4.2kV with 80 - 120mA on the deposition materials at 350$^{\circ}C$ in 2.0 X 10-6 torr vacuum. Ti/TiN/HA multilayer coated surfaces and layers were investigated by SEM and XRD. A saturated calomel electrode as a reference electrode, and high density carbon electrode as a counter electrode, were set according to ASTM GS-87. The potentials were controlled at a scan rate of 100 mV/min. by a potentiostat (EG&G Co.273A) connected to a computer system. Electrochemical tests were used to investigate the electrochemical characteristics of Ti/TiN/HA coated and shot peened materials in 0.9% NaCl solution at 36.5$^{\circ}C$. After each electrochemical measurement, the corrosion surface of each sample was investigated by SEM.

• Korean Journal of Community Nutrition
• /
• v.13 no.4
• /
• pp.489-498
• /
• 2008

This study was carried out to identify bone mineral density(BMD), body composition, lifestyle and dietary habits of young women by physical measurement and questionnaires. The study subjects, 190 young women living in Seoul, were divided into three age groups: $20{\sim}24$ years(93), $25{\sim}29$ years(44) and $30{\sim}39$ years(53). There was no significant difference in mean body muscle mass, protein, mineral, body fat and BMI among the three age groups. The rate of low weight(18%) in 20 years group was higher that of the 30 years(11.3%). The mean BMD and T-score were $0.44g/cm^2$ and -0.66. BMD and T-score of the forearm bone were significantly higher in the $30{\sim}39$ years group. But BMD and T-score of calcanues were not significantly different among the three age groups. The rate of normal, osteopenia and osteoporosis subjects by BMD were 60.5%, 38.4%, 1.1%, respectively. The rate of osteopenia in $20{\sim}24$ years group was significantly higher than the other age groups. The rate of meal irregularity was significantly higher in $20{\sim}24$ years group. The rate of women who walk and are exposed to sunlight more than 1hr per day were significantly higher in $20{\sim}24$ years group than the others. However, the score of food behaviors is significantly higher(bad) in $20{\sim}24$ years group than the others. The relationship between BMD and frequency of food intake showed significant differences in beans, broom, seaweed and rice wine. In conclusion, the risk rate of BMD was very high, 40% of the subjects, and the risk rate of BMD was higher in 20 years group than 30 years group, and the rate of low weight in 20 years group was higher than in 30 years group. The food habits and behaviors were not healthy enough. Therefore, nutrition education is needed for bone health.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.20 no.1
• /
• pp.73-80
• /
• 2008

An hydraulic experiment was carried out in an open channel flume in order to improve the technique of designing shape of the sluice used for tidal power generation, which greatly affects the economical efficiency of the construction of a tidal power plant. To predict the influence of change in the major design parameters relating to the sluice shape on the water discharge capability of the sluice, it was necessary to perform a precise experiment that is discriminated to previous feasibility studies or design projects. For this purpose, by installing various flow straighteners and rectifying structures inside the water supply system and the rectifying tank, the flow in the flume was stabilized as tranquil as possible. In addition, the measuring instruments and the location of installing them were carefully determined so as to minimize the errors intervened during the measurement of water discharge and water level. The method of estimating head difference between upstream and downstream of the sluice was also developed by taking account of the head loss due to the friction at the bottom and side walls in the flume.