• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2005.10a
• /
• pp.181-185
• /
• 2005

The treated ballast water from previous treatment contains microorganisms and pathogenic organisms in an filtration treatment system. The advantage of this process can be filtrated to minimize the demage to screen clogging of drum filter with sweeping the solids off rotating the surface of the filter. Another advantage is to drop off the solids with controlling revolution of drum screen in pretreatment filtration process. Also the fact that it is easy to attach and detach a several type of screen for getting the expected water quality is another advantage, too. Filter rotation speed at 20rpmis 40.5cmHg and 40rpm is 36.6cmHg. Filter out impurities from ballast water over 60rpm is 35cmHg. Filtration system removal aquatic organism over $80{\mu}m$ in ballast water. This study shows that the filtration treatment system has a potential for the removal of ballast water.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.20 no.4
• /
• pp.95-105
• /
• 2021

Road surface damage detection is essential for a comfortable driving environment and the prevention of safety accidents. Road management institutes are using automated technology-based inspection equipment and systems. As one of these automation technologies, a sensor to detect road surface damage plays an important role. For this purpose, several studies on sensors using deep learning have been conducted in recent years. Road images and label images are needed to develop such deep learning algorithms. On the other hand, considerable time and labor will be needed to secure label images. In this paper, the adversarial learning method, one of the semi-supervised learning techniques, was proposed to solve this problem. For its implementation, a lightweight deep neural network model was trained using 5,327 road images and 1,327 label images. After experimenting with 400 road images, a model with a mean intersection over a union of 80.54% and an F1 score of 77.85% was developed. Through this, a technology that can improve recognition performance by adding only road images was developed to learning without label images and is expected to be used as a technology for road surface management in the future.

• The Journal of Korean Medicine
• /
• v.23 no.1
• /
• pp.100-111
• /
• 2002

Objectives : In order to obtain the clinical type of facial palsy sequelae and try to make the treatment protocols for each, I observed patients who visited Gunpo-Wonkwang oriental medicine center with Bell’s palsy sequelae that were treated over three months. Methods : I make the value standard of muscle paralysis, contraction, synkinesis and acquired the results as follows. Results and Conclusions : 1. The distribution of age and sex was as follows : females of 41-50 years were the most common demographic, females of 51-60 years and males of 31-40 years were the second, males of 51-60 years were the third, females of 21-30 years and males of over 60 years were the fourth, and males of 41-50 years were the fifth. 2. The distributions of period of disease were as follows : 3-6 months was the most, 12-18 months was the second, 6-12 months and over 24 months was the third, and 18-24 months was the fourth. 3. The sequelae distributions of disease were as follows. In the group of 3-6 months, 12 persons (80%) showed palsy and atrophy, 10 persons (66.6%) showed synkinetics. In the group of over 6 months, all patients showed muscle palsy, muscle atrophy and synkinetics. All groups showed lower sensitivity of muscles, but the group of 18-24 months and the group of over 24 months showed more. Tinnitus was shown by the groups of 12-18 months and 3-6 months. Facial muscle pain was shown by the group of3-6 months only, Crocodile's tear was shown by the groups of 18-24 months and over 24 months. 4. The total palsy rates of sequela patients and palsy rates by muscle for disease period were as follows. The total palsy rate was 27.94%; the palsy rates for the group of 6-12 months and the group of over 24 months was lower than the total palsy rate. The rates of the groups of 3-6, 12-18, 18-24 months were higher than the total palsy rate. The palsy rate of zygomatic minor, levator labii superior muscle was higher than the total palsy rate for all groups. 5. Synkinetics manifestation rates by disease period were as follows. Total synkinetics manifestation rate was 73.81 %; the manifestation rate of the group of 6-12 months was lower than total synkinetics manifestation rate. For the groups of 12-18, 18-24, and over 24 months it was more than the total synkinetics manifestation rate. The group of over 24 months, total synkinetics induced by orbicularis oculi muscle and orbicularis oris muscle. 6. Facial muscle atrophy rates by disease period were as follows. Total atrophy rate was 5.26%; in the groups of 6-12, 18-24, over 24 months, the atrophy rates were higher than the total atrophy rate. The groups of 3-6 and 12-18 months showed lower than the total atrophy rates, while the atrophy of the levator palpebrae superioris muscle and levator palpebrae inferioris muscle was higher than in other groups.

• Polymer(Korea)
• /
• v.28 no.1
• /
• pp.35-40
• /
• 2004

The formation mechanism of void defect which deteriorate composite's property is various according to each composite process. In this paper, void formation and growth mechanism is analyzed by thermal analysis and GC/MS. We made a vacuum chamber for observing pressure effect. Thermal analysis has been done in various condition. Elements of volatiles during resin curing were turned out by GC/MS. The most of volatiles of polyester were composed of styrene (over 80%) and a small quantity of toluene. In case epoxy resin, butyl glycidyl ether was the main element of volatiles (over 90%). We concluded that the original sites of void growth existed in resin and they were eliminated by vacuum and heating process. And the growth of void was influenced by water, diluents, solvent, and reactants in resin.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2003.11a
• /
• pp.138-138
• /
• 2003

Low temperature co-fired ceramic (LTCC) technology offers significant benefits over the other established packaging technologies for high density, high microwave frequency, and fast signal application. Most conventional electroceraramics do not meet the basic requirements in respect of sinterability for LTCC technology. Attention is, therefore, focused on the role of glasses because of the capability they supply with lower sintering temperatures. In this study, commercial ceramic (MBRT-90) in the system BaO-N $d_2$ $O_3$-Ti $O_2$ (BNT: 40 ~ 80 wt%) and L $a_2$ $O_3$- $B_2$ $O_3$-Ti $O_2$ glass (LBT;60 ~ 20 wt%) were prepared. These glass/ceramic composites were evaluated for sintering behavior, phase evaluation, densities, interface reaction, crystallinity, microstructure and microwave dielectric properties. It was found that the addition LBT glass frits significantly lowered the sintering temperature to below 90$0^{\circ}C$ and as temperature increased (750~90$0^{\circ}C$) densification developed dynamically which was meant to be as over 95% of relative density. It is supposed that in the microstructure, the grain size was increased accompanying with the formation of different phases such as LaB $O_3$ and Ti $O_2$ under the condition of increasing sintering temperature. The sintered bodies represented applicable dielectric properties, namely 20 ~ 40 for $\varepsilon_{{\gamma}}$, ~ 10000 GHz for Q* $f_{0}$ and 10~80 ppm/$^{\circ}C$ for $\tau$$_{f}$. The results suggest that the composite is one of feasible candidates for the microwave use in LTCC technology.y.e use in LTCC technology.y.

• Asian Journal of Turfgrass Science
• /
• v.26 no.2
• /
• pp.102-109
• /
• 2012

Commercial formulation of fungicides was studied in the golf course for evaluation against Typhula incarnata causal agents of gray snow mold. Efficacies of fungicides application, fungicide mixture, fungicides applied method (irrigation and spray) and fungicides applied time (early fall and late fall) were evaluated for their influence on the chemical control of gray snow mold of turfgrass during the winter season in Yongpyeong golf course, Korea. Unsprayed control has significantly more disease severity than three fungicides (azoxystrobin, propiconazole, and tebuconazole) were applied to field plots. Effect of three fungicides was over 80% with control value for controlling gray snow mold on Kentucky bluegrass and creeping bentgrass species. Effect of fungicide mixture with different family groups had an over 93% control value of gray snow mold on Kentucky bluegrass species. It was not significantly difference in fungicidal effect according to applied method (irrigation and spray) with azoxystrobin on Kentucky bluegrass and creeping bentrasss species. Effect of fungicides applied time was a significantly difference on disease control by tebconazole early fall spray.

• Research in Community and Public Health Nursing
• /
• v.4 no.2
• /
• pp.117-130
• /
• 1993

There has been a rapid growth in Korea since 1962 because of the success of the 5-year Economic Plan. The number of industrial work and workers has also made had a rapid increase. Consequently, the management of occupational health for the purpose of promoting health in industrial workers is needed especially in the health examination program. The purpose of this study was to analyze the Knowledge, and Attitude among industrial workers of health examination programs. The target population was 402 industrial workers from 4 factories in Kangwon province. A survey was conducted to collect data by a self administered questionnaire from October 29 to November 5. A sixty four item questionnaire was designed to collect data concerning Knowledge, and Attitude of health examination of industrial workers. The data was analyzed by means of percentage, mean, T-test, ANOVA, Pearson's correlation coefficient. The major findings were as follows : 1. The respondents presented the following picture : The male population was 88%. 57% of respondents were age 25-34 years old. 69.4% of respondents were married. 73.4% of respondents were high school graduates. 80.8% of the respondents were working over 48 hours per week. The respondents with over 10 years on the job were 31.9% of the respondents. Health examination were given to the respondents as: pre-employment health examination 90.5%, general health examination 91.5%, and special health examination 31.5%. 2. The Knowledge level was different in health examination items. 80.5% of respondents had knowledge about hearing test, body weight, visually, chest X-ray like simple things. Below 50% of respondents had knowledge of urine test, liver function test, and career history. 3. Attitude status about health examination showed an average score 36.5(median 33) of satisfaction, 26.93(median 21) of importance, 13.84 (median 21) of content, 10.46(median 12 of reliability on health examination results. 4. The level of Attitude on health examination was significantly different than the Knowledge level. 5. The relationship among stated variables such as satisfaction, the perceptions of importance on health, health examination, the result and follow up after health examination were shown to reflect neither positively nor negatively on each other.

• Resources Recycling
• /
• v.9 no.4
• /
• pp.37-43
• /
• 2000

Leaching of $LiCoO_2$ as a cathodic active materials for recovering Li and Co from spent lithium ion battery was investigated in terms of reaction variables. At the optimum condition determined in the previous work, Li and Co in a $H_2SO_4$ and $HNO_3$ solution were dissolved 70~80% and 40%, respectively. Li and Co were leached over 95% with the addition of a reductant such as $Na_2S_2O_3$ or $H_2O_2$. This behavior is probably due to the reduction of $Co^{3+}$ to $Co^{2+}$. Leaching of $LiCoCo_2$ powder obtained by calcination of an electrode materials from spent batteries was also carried out. Leaching efficiency of Li and Co were over 99% at the optimum condition with $H_2O_2$ addition of 1.7 vol.%. It seems to be due to the activation of $LiCoO_2$ by repeated charging and discharging or an imperfect crystal structure by deintercalation of Li.

• Journal of the Korea Institute of Building Construction
• /
• v.23 no.4
• /
• pp.405-416
• /
• 2023

Recent seismic activities in countries like China and Turkey have underscored the widespread and severe damages that earthquakes can inflict globally. Being situated in a seismically active zone, South Korea can no longer regard itself as immune to earthquake hazards, necessitating the urgent adoption of proactive measures against such threats. The government has been proactive in evaluating, formulating processes, and methods for the seismic retrofitting of public buildings lacking in earthquake resistance. However, enforcement mechanisms for privately-owned apartment complexes are absent, and in the face of insufficient previous research and guidelines, preemptive measures for public safety remain alarmingly inadequate. With over 48% of residential structures in Korea aged over 30 years, and apartment complexes constituting more than 80% of these, the gravity of the situation is undeniable. This study deduces key factors for seismic retrofitting of apartment buildings like earthquake zones, soil type, building significance, aging degree, vulnerability, etc., based on building seismic design codes. It further proposes an algorithm for a more succinct and efficient determination of the priority of seismic reinforcements for apartment buildings.

• Korean Journal of Environment and Ecology
• /
• v.26 no.3
• /
• pp.367-373
• /
• 2012

Population ecology (Ecological characteristics) of Squalidus japonicus coreanus from the Namhan River(Yangpyeong-gun Yangpyeong-eup Changde-ri), Gyeonggi-do, Korea were investigated from January to December 2011. Short barbel gudgeon inhabits habitats run of the lower river. The stream bed was mostly covered sand. Their current velocities were 0.14~1.38m/sec and depths were 80~120cm. The sex ratio of female to male was 1 : 0.82. It is presumed that the spawning season is from June to July and water temperatures were $18.5{\sim}24.3^{\circ}C$. Sexually matured individuals appeared over the two year of age. Frequency analysis of total length indicated that the group with 34~50mm in total length was one year old, the 51~74mm was two years old, and the group over 75mm was three years old. The average number of eggs in the ovaries was estimated as 1,871 per matured female. Stomach content of S. japonicus coreanus were Cyanophyta, Chlorophyta, Bacillariophyta, Rotatoria, Crustaceae, Copepoda, Ephemeroptera, Diptera, and Nematoda. omnivorous, mainly feeds on benthic invertebrates such as chironomidae larvae.