• Journal of KSNVE
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• v.6 no.1
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• pp.107-114
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• 1996

The damping characteristics of a cylindrical structure containing oil and bearing balls is investigated for external bending forces. The experimental data obtained through the use of bearing balls with viscous oil in a column is given and analyzed. The viscous action of the oil and inertia effects of the balls on the inside of column create a drag force. The drag force dampens the vibration of the column. This study aims to search for an optimum combination of oil and balls which would produce maximum damping. Machining oils of various viscosities along with ball bearings of various sizes place inside cantilevered aluminium tubes of various diameters to create a rig on which the damping properties of the oil and balls can be studied. The contileved tubes are studied in both horizontal and vertical positions in order to gauge the effect of gravity on the system. The actions of the ball in the column and damping characteristics are investigated according to the dimensionless terms. The Buckingham theorem is used to reduce the variables and to predict the damping of an oil ball column. Though the damping ratio remains fairly constant in the horizontal position of column, the damping ratio begins to increase as the ratio of the number of balls and column length rise above 0.28 in the vertical position of oil ball column. The ratio of the ball diameter to column diameter influences the damping ratio with an optimum diameter ratio. Slenderness ratio and gravity effects on the damping ratio ane investigated.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.243-250
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• 2008

In Korean, nine tar colors are permitted in foods. This study assessed these compounds in the favorite food items of children found near elementary schools. A total of 439 items categorized under six food types were included in the analysis. The most frequently detected tar colors were tartrazine (Y4), Brilliant Blue FCF (Y5), Allura Red, and Sunset Yellow FCF, respectively. One or a mixture of two tar colors were commonly found in products such as gums, ice bars, soft drinks, and cereals. However, most often, combinations of two or three tar colors were detected. The levels of tar colors in candies, chocolates, gums, ice bars, cereals, and soft drinks were 0.11-1169.58 mg/kg, 0.73-468.02 mg/kg, 0.10-602.46 mg/kg, 0.25-162.32 mg/kg, 0.11-753.68 mg/kg, and 0.21-69.45 mg/kg, respectively. Tar color levels were higher in chocolates and gums than in soft drinks and ice bars. And Y4 and Y5 were detected at the highest levels. For ages 7-12, the total estimated daily intake (${\sum}EDI$) of each tar color ranged from 0.004 to 1.017 mg/day/person. These values were 0.02-5.98% of the FAO/WHO's acceptable daily intake (ADI).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5096-5110
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• 2015

The purpose of this study was to identify the effects of brain wave change through therapeutic recreation programs on depression, sleep disturbance and quality of life among elderly with dementia. The subjects of this quasi-experimental study consisted of two groups, one experimental group (N=14) and one control group (N=18), after excluding 8 participants from a total of 40 participants. The subjects of experimental group were randomly selected from the elderly (order than 65 years old) of senior care center in Daejoen and participated in 3-month therapeutic recreation program. On the other hand, the subjects of control group did not participated in any therapeutic recreation program. Each group's pre-post brain wave change, depression, sleep disturbance and quality of life were estimated. Through ANCOVA and Analysis of Structural Equation Modeling with SPSS window 17.0 and AMOS 7.0, this study found followings. Frist, the therapeutic recreation program group indicated significant improvement of brain waves, sleep disturbance and quality of Life. In addition, depression was significantly reduced in the therapeutic recreation program group. Second, significant causal relationships was found among brain waves, depression, sleep disturbance, and Quality of Life.

• Journal of the Institute of Convergence Signal Processing
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• v.15 no.4
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• pp.176-182
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• 2014

This paper introduces the development of global fringe search (GFS) software for preprocessing of Daejeon Correlator. In case of the VLBI observation, a observer conducts the observation for the reference sources with strong and point-like radio stars on schedule in order to confirm the well-observedness of the radio source by the radio telescope. The correlator performs the correlation for the reference sources to detect the fringe completely. We developed the GFS software by calculating the precise delay time between each observatory based on specific observatory. Then, this software calculates the precise delay time by using the delay model (correlator model) of reference source and information of time offset between the Hydrogen Maser frequency standard and GPS (Global Positioning System) clock located in each observatory through the correlation preprocessing. In order to confirm the performance of the developed software, experiments were carried out for the reference sources and target sources observed by the KaVA (KVN and VERA Array). Experimental results show that the GFS software has effectively good performance by finding the precise delay time offset according to the comparison between the compensated delay time offset and one without compensation.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.3
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• pp.11-21
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• 2015

Emergency Medical Service(EMS) has become focused due to all kinds of disaster and a great number of casualties. The 119 emergency vehicles' dispatching methods are now being focused, for travel time of ambulances are the critical components in terms of saving human lives. Therefore, this study tried to rearrange 119 EMS regions more efficiently. For this study, Daejeon Metropolitan City's real call cases were analyzed. In order to rearrange the regions, OD Cost Matrix analysis was performed between 800 thousands random points and 26 departments in the Daejoen Metropolitan City. By creating Thiessen Polygon from the random points, a new region was created. As a results, average areas of the regions were reduces from 32 square kilometers to 20 square kilometers, and average time of arrivals are were also improved. Hence, if related organizations plan to rearrange EMS regions, they may utilize this study.

• Food Science and Preservation
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• v.16 no.1
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• pp.23-32
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• 2009

This study evaluated quality characteristics of spirulina (0.63, 1.25, and 2.5%, all w/w) added noodles during storage at 4C. Total bacterial counts in raw spirulina added noodles were higher than those of the control during storage, but no bacteria were detected in cooked noodles. Escherichia coli was not detected in any group. The weight loss, volume loss, and moisture absorption of spirulina added noodles were somewhat greater than control values. Moisture contents of spirulina added noodles both before and after cooking decreased as the spirulina level increased. During storage, moisture loss from spirulina added noodles was a little greater than from the control. Hunter color values for L (lightness), a (redness), and b (yellowness) decreased during storage. The spirulina added noodles had significantly greater hardness, cohesiveness, gumminess, and chewiness compared with the control. The antioxidant activity of spirulina added noodles increased with spirulina level. A sensory preference test revealed that noodles with 1.25% spirulina received the highest scores for chewiness, overall preference, and buying intention. It is suggested that spirulina could be added to noodles at a concentration of up to 1.25% to improve quality.

• The KIPS Transactions:PartD
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• v.11D no.6
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• pp.1259-1268
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• 2004

To organize training in limited training area for an actuai combat, realistic training simulation plugged in by various battle conditions is essential. In this paper, we propose a virtual target overlay technique which does not use a virtual image, but Projects a virtual target on ground-based CCD image by appointed scenario for a realistic training simulation. In the proposed method, we create a realistic 3D model (for an instructor) by using high resolution Geographic Tag Image File Format(GeoTIFF) satellite image and Digital Terrain Elevation Data (DTED), and extract the road area from a given CCD image (for both an instructor and a trainee). Satellite images and ground-based sensor images have many differences in observation position, resolution, and scale, thus yielding many difficulties in feature-based matching. Hence, we propose a moving synchronization technique that projects the target on the sensor image according to the marked moving path on 3D satellite image by applying Thin-Plate Spline(TPS) interpolation function, which is an image warping function, on the two given sets of corresponding control point pair. To show the experimental result of the proposed method, we employed two Pentium4 1.8MHz personal computer systems equipped with 512MBs of RAM, and the satellite and sensor images of Daejoen area are also been utilized. The experimental result revealed the effective-ness of proposed algorithm.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.237-245
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• 2007

We tested for residual pesticide levels in agricultural products purchased from 5 provinces within the middle region of Korea during 2006. A Total of 488 samples of 23 different types of agricultural products were analyzed by GC/MS, GC-NPD, and LC/MS/MS. We used multi-analysis methods to analyze for 231 different pesticide types; a single residual pesticides were detected in 92 samples (18.9%), of which 9 samples (1.9%) exceeded the Korea Maximum Residue Limits (MRLs). we detected pesticide residue in more than 50% of the pepper leaf and welsh onion samples. For the welsh onions, 16 among the 30 analyzed samples contained pesticide residue, and 4 samples exceeded the Korea MRLs. Among the 234 kinds of pesticides we tested for, 42 were detected, and 21 of them were detected more than twice. Six pesticide residue types, including cypermethrin, iprodione, fludioxonil, ethoprophos, flutolanil, and lufenuron, exceeded the MRLs. No residual pesticides were detected in 396 of the samples (81.1%), and the residual pesticide levels in 83 samples (17.0%) were lower than the Korea MRLs, indicating that 98.1% of the samples were relatively safe.

• 대한공업교육학회지
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• v.38 no.2
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• pp.156-175
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• 2013

The purpose of this study was to verify that the impacts of experience of donation for education to improve the teaching efficacy of pre-technology teacher. The Invention experience of donation for education was performed with Invent-touring sponsored by Chunnam National University Invention Education Center for Teachers and was included by development of creative problem solving program, program execution and evaluation. Research participants were Technology education Majors and minors 20 students. The active locations were D children community center, K alternative school, D Elementary School and D middle school. For the study, various literature researches were reviewed intensively about donation for education and teaching efficacy. The instrument for the study was the modified STEBI(Science Teaching Efficacy Beliefs Instrument) for technology education by 3 experts. This study was designed by single group pre and post test design (One-Group Pretest-Posttest Design) and was conducted by the pre-test and post-test. Check the reliability of the tool was conducted with Cronbach ${\alpha}$ coefficient analysis, pre-test 0.840, post-test 0.746. The analysis of data from the 5% significance level, paired sample t-test was performed using the SPSS 19.0 statistical tool. The results were as follows: 1. Teaching efficacy of pre-technology teachers who participated in the invention experience for educational donation technology has improved. 72. The qualitative study was performed by the interviews with students who participated in. Humanism was positively change and learning opportunity was provided to develop the competence of technology education teacher. Based upon the conclusion of this study, the donation activity for invention education need to use learning strategies for pre-technology teacher to improve teaching efficacy.