• Structural Engineering and Mechanics
• /
• v.48 no.4
• /
• pp.479-500
• /
• 2013

This paper presents the experimental as well as analytical study conducted on layer-bonded scrap tire rubber pad (STRP) isolators to develop low-cost seismic isolators applicable to structures in developing countries. The STRP specimen samples were produced by stacking the STRP layers one on top of another with the application of adhesive. In unbonded application, the STRP bearings were placed between the substructure and superstructure without fastening between the contact surfaces which allows roll-off of the contact supports. The vertical compression and horizontal shear tests were conducted with varying axial loads. These results were used to compute the different mechanical properties of the STRP isolators including vertical stiffness, horizontal effective stiffness, average horizontal stiffness and effective damping ratios. The load-displacement relationships of STRP isolators obtained by experimental and finite element analysis results were found to be in close agreement. The tested STRP samples show energy dissipation capacity considerably greater than the natural rubber bearings. The layer-bonded STRP isolators serve positive incremental force resisting capacity up to the shear strain level of 150%.

• Journal of the Korean Society of Industry Convergence
• /
• v.19 no.4
• /
• pp.223-230
• /
• 2016

This paper presents data-driven thermal protection algorithm for preventing overheating of automotive sunroof motor. When a sunroof motor operates abnormally, its coil is overheated and it is failed. Besides, drivers and passengers are damaged. Hence, the sunroof motor observes its temperature and will be stoped when its temperature reach a predefined level. In order to implement low-cost thermal protection function, we drew a knowledge-based temperature increasing and decreasing curve from the result of experimental test. And then, we implemented data-driven thermal protection algorithm which prevents motor's On/Off operation according to motor operating voltage and motor speed. Finally, we implemented experimental test bed and evaluated its feasibility.

• The Journal of the Acoustical Society of Korea
• /
• v.13 no.4
• /
• pp.69-76
• /
• 1994

In this study we developed monosyllable lists for articulation test for Korean. We sampled 103, 581 colloquial monosyllables, applied them to five selection rules that based on Korean linguistic characterisitcs, and finally constructed five different lists with fifity monosyllables. The validity test using the monaural impairment factors such as S/N ratio and cut-off frequency showed that articulation scores were changed systematically according to the level of impairment factors. In addition, we investigated the effect of azimuth of a single competing sound source upon articulation scores. The syllables were always reproduced by the loudspeaker in front of the subject, while Hoth noise( -5dB/oct) were reproduced by the loudspeaker with varying azimuth around subject. The result indicated that the articulation depended on the azimuth of competing sound sources and no significant differences among lists were found in all experimental conditions.

• Journal of Fashion Business
• /
• v.7 no.2
• /
• pp.1-14
• /
• 2003

This study were to grasp the present situation of the pet wear market and the problem of pet wear, and to develop the pet wear pattern which agrees well to dog's shape and movements. We carried out survey research to analyze the actual pet wear market condition for a dog-lover, and movement analysis and sensory test to develop a pattern for Maltese which was the favorite dog among Korean. For data analysis, ANOVA with duncan test, T-test were conducted using SPSS statistic program(ver. 10.0). The results are as follows: 1. The results of the survey research, 75% of dog-lover had a pet wear and favorite was T-shirts. The problems of wearing T-shirts were 'too tight seam sleeve and bodice(front legs hole)', 'the clothes easily hang down' and 'easily taken off due to large neck size'. 2. The ease amount of the developed pattern was given according to the results of dog's shape and movement analysis, and the results of sensory test, there is a significant difference in the following items: depth of front neck line, front chest${\to}$abdomen curve, ease amount of sleeve, comfort level of leg parts. 3. The size of each parts of the developed pattern in this study were as follows : neck girth 27.0cm, body girth 40.0cm, back length 26.0cm, front leg girth 23.0cm, sleeve length 20.7cm, sleeve width 14.4cm. But, there exists some limits to generalize these results since dog's body size and shapes are various according to dog species. Therefore, further studies are needed to develop each pet wear pattern for each dog species.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.46 no.8
• /
• pp.694-701
• /
• 2018

Civil aircraft noise certification standard is based on the ICAO Annex 16 Vol. 1. And, the standard uses A-Weighted SPL, EPNL and SEL method depending on the aircraft category. Korean noise standards, KAS 36 and other nation's CS 36 and FAR 36 noise standards were developed and revised according to the international noise standards, ICAO Annex 16. And, the national noise requirements are equivalent each other. The small airplane noise certification requires only take-off noise level with A-Weighted SPL in dB(A) unit. The first Korean aircraft noise certification was performed for the KC-100 certification in August 2012 with Korean authority and U.S. FAA. The noise certification requires much knowledge and experience in flight tests and noise data processing. In this study, the noise test requirements, test conditions and data correcting methods are shown with the test examples.

• Journal of Veterinary Clinics
• /
• v.32 no.4
• /
• pp.324-329
• /
• 2015

The primary aim of this study was to investigate biosecurity practices in pig farms and to determine the major risk factors associated with PCV2 infection for a sampled swine population in Korea. To this end, we analyzed data from a cross-sectional study of 296 farrow-to-finish farms, which was conducted between March and September 2014 to explore the prevalence of swine disease at farm level. Face-to-face interviews by on-site visit of trained veterinarians were conducted with the farm owners or managers using a standardized questionnaires with information about basic demographical data and management practices. Farms were classified as negative or positive through the use of infection profiles that combined data on serological testing including PCR antigen test result, antibody titer and sero-conversion pattern at each age category taking into account vaccination status. Data were analyzed using multivariate ordinal logistic regression. Results from this study indicated that biosecurity level of the farms was considered not good given low compliance of the biosecurity programs and facilities in the farm: off-site removal of dead stocks (7%), off-site location of storage facility for incoming feeds (12.6%), off-site pick-up location for finishers (19.3%), restrictions on feed supplier vehicles for farm entrance (19.6%), restriction of finisher trucks entering the farm (22.4%), and restriction on manure disposal trucks entering the farm (26.4%). In the final model (n = 255), allowance of finisher truck driver to the pig unit had increased risk of infection (OR = 2.4, 95% CI 1.22-4.67) whereas farms with a sign forbidding the entrance had decreased risk of infection (OR = 0.19, 95% CI 0.10-0.58). Further comprehensive research with larger sample size is required to better understand the multifactorial characteristic that some predisposing risk factors that were not available in this study. To the best knowledge of the authors, this was the first study to use empirical data to report risk factors associated with PCV2 infection in the Korean pig farms. Results from the current study could be used to decide optimal biosecurity measures to reduce the impact of PCV2 infection to farmers and policy makers.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.19 no.4
• /
• pp.74-83
• /
• 2011

In this study, to estimate the transforming (runoff and leachate) rate of the livestock resources applying to agricultural crop land as fertilizer, field scale test was conducted and the results were obtained as follows. According to results of livestock resources effect to agricultural land, the total amount of harvested crop from testing bed was $0.437kg/m^2$, and nutrient contents were $0.024{\pm}0.006%$ and $0.020{\pm}0.004%$ for N and P, respectively. Dynamics of contaminants in the livestock resources to be supplied to agricultural crop land showed that concentrations were continuously decreased to the level of blank test bed until 60 days of planting. The amount of runoff from farm land showed the tendency to increase according to the increase of rainfall intensity. Run-off ratio of 10mm/h rainfall intensity for agricultural land showed that each contaminant concentration was increased due to rainfall intensity with 8 mm/h, specifically SS showed the highest increase.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.29 no.1
• /
• pp.245-251
• /
• 2005

When we design coastal and harbol facilities deepwater design wave and wind speed are the important design parameters. Especially, the analysis of these informations is a vital step for the point of disaster prevention. In this study, we made and an extreme value analysis using a series of deep water significant wave data arranged in the 16 direction and supplied by KORDI real-time wave information system ,and the wind data gained from Wan-Do whether Station 1978-2003. The probability distributions considered in this characteristic analysis were the Weibull, the Gumbel, the Log-Pearson Type III, the Normal, the Lognormal, and the Gamma distribution. The parameter for each distribution was estimated by three methods, i.e. the method of moments, the maximum likelihood, and the method of probability weight moments. Furthermore, probability distributions for the extreme data had been selected by using Chi-square and Kolmogorov-Smirnov test within significant level of 5%, i,e. 95% reliance level. From this study we found that Gumbel distribution is the most proper model for the deep water design wave height off the southwest coast of Korea. However the result shows that the proper distribution made for the selected site is varied in each extreme data set.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.66 no.12
• /
• pp.1836-1843
• /
• 2017

In this paper, we investigated fire cases those are believed to be caused by explosion of a electrolytic motor start capacitor. Using two types of commercially available electrolytic motor start capacitors, capacitor current and the possibility of capacitor explosion were tested. And the ignition possibility of the internal material leaked from a capacitor was also tested. In addition, experiments were conducted to see if the fire could spread when a capacitor was exposed to an external flame. From our test we observed that the current of the electrolytic motor start capacitor rose continuously to a certain level by product, if the capacitor was continuously energized with working voltage, and then the capacitor was exploded. The gas and liquid leaked from the capacitor by the explosion could ignite by an electric arc and an external flame. The capacitor current at explosion was different product by product, but each product had a certain current level at explosion. And the increase rate of the capacitor current until explosion was 24% and 31% for the products used in the experiment. We proposed the capacitor explosion prevention method that cuts off power when the capacitor current rises to a certain threshold level. The proposed method can be used if the current of the applied electrolytic motor start capacitor rises continuously and then the capacitor is exploded at a certain current level when the capacitor is energized continuously.

• The Journal of Korean Society for School & Community Health Education
• /
• v.16 no.2
• /
• pp.89-100
• /
• 2015

Objectives: This study was carried out to measure knowledge, attitude, and practice and related factors of low-salt diet among university students. Methods: Data from a convenience sample of 251 nursing and engineering students of two universities in south-western part of Korea were collected during March 16~20, 2015 using a self-reporting questionaire and urine test. The instruments developed by Lee and Song(1999) were used to measure knowledge and practice, and Ahn(2013) for attitude toward low-salt diet. A spot urine salt stick($SaltSinal^{(R)}$) was also used to evaluate practice of low-salt diet. Data were analyzed using SPSS 21.0, and t-tests, ANOVA, Pearson correlation, and Scheffe test were used. The study was IRB approved. Results: Knowledge, attitude, and practice of low-salt diet was low and spot urine salt level was high among university students. Knowledge and attitude were higher and spot urine salt level was lower among nursing students. Knowledge and attitude were related to gender and drinking. Living arrangement, monthly allowance, smoking, frequency of eating-out, frequency of breakfast were shown not to be related to knowledge and attitude. None of the variable investigated were significantly related to practice of low-salt diet. However, spot urine salt was related with gender, living arrangement, and smoking. Conclusions: A rigorous health education is necessary in order to lower dietary salt among university students. Considering frequent eating-out among university students, it is also very important to lower salt amount in foods sold on- and off-campus.