• Journal of the Korean Society for Marine Environment & Energy
• /
• v.5 no.4
• /
• pp.41-47
• /
• 2002

The surface current in the region from Mara-do to mid of the Pacific has been measured by tracking the position of a buoy. The buoy was accidentally released from its original location, near Mara-do, and it has been drifting following the surface current. The tracking started on 27 December 2001 and continued until 29 June 2002. We combined the trace oi the buoy with the wind data available.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.3 no.1
• /
• pp.7-18
• /
• 1970

The present paper deals with mortality and pathogenetic investigation of the oysters Crassostrea gigas cultured by tile coventional bamboo and hanging method in Kimhae and Koje-Do in 1969. The results of the investigation may be summarized as follows: 1. Mortality of the oysters by the bamboo method in Kimhae was $9.5\%$ in June, $10.2\%$ In July, $12.3\%$ in August and $12.1\%$ in September, respectively, 2. Mortality of the oysters cultured by the hanging method in Koje-Do was $2.4\%$ in June, $2.9\%$ in July, $30.7\%$ in October, $37.3\%$ in November and $30.0\%$ in December, respectively 3. The diseased oysters had severe inflammation, necrosis and multiple abscess in the epithelia of stomach, mid-gut, digestive tubules, blood vessels and gonads, mucous membrane and surrounding tissue. 4. From August gram negative bacteria were found in the nodules of connective tissue and multiple abscess of the diseased oysters. Particularly the connective tissue of the diseased oysters contained more bacteria than epithelia. 5. Since the bacteria are less abundant in the region of digenerated tissue, mortality of the oysters is not caused only by the infectious bacteria but seems that is also caused by other environmental factors such as extreme temperatures and salinities.

• Korean Journal of Ichthyology
• /
• v.23 no.2
• /
• pp.106-110
• /
• 2011

Fine structure of spermatozoa of the bastard halibut (Paralichthys olivaceus) is described. Its structure is characterized by acrosomeless, having a spherical head region and a small mid piece containing five mitochondria disposed one row. The flagellum inserts centrally on the nucleus and has lateral ribbons. The present study supports the suggestion that spermatozoal ultrastructure is of taxonomic importance and may be a phylogenetic criterion in teleostei.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.12 no.1
• /
• pp.3-11
• /
• 1998

The influence due to particle contaminated on spacer surface is remarkable in the decreasing of dielectric strength in SF6 GIS. In relation with this problem, We studied, AC flash-over voltage characteristics and breakdown mechanism are investigated under metallic and insulating particle initiated condition in SF6 gas by varying the particle position, particle shape with a plane-plane electrode. The main results are as follows $\circled1$ Influence of the flash-over voltage decrease for particle position is lowest in mid gap and is highest in separated small gap on electrode. $\circled2$ The metallic particle shape which results in the more reduced flash-over voltage, the FOV saturation moved in to the region of low pressure. $\circled3$Insulating particle less than 0.6[mm] are not almost influenced by the flash-over Voltage.oltage.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1997.11a
• /
• pp.356-359
• /
• 1997

The Effects of different melting temperature and holding time in the melting temperature on J$\sub$c/ of YBa$_2$Cu$_3$O$\sub$x/ based superconducting bulk using MPMG process were investigated. the value of critical current density was the largest at l120$^{\circ}C$, the melting temperature which is appointed to the mid point of (Y$_2$BaCuO$\sub$5/ + Liquid)region. With the melting temperature in which the value of J$\sub$c/ is the largest, J$\sub$c/ was again measured to see whether the holding time at this proper melting temperature has the effect on the critical characteristics. From the result above it was concluded that the melting temperature and holding time were important to improve the J$\sub$c/ and the formation of the Y$_2$BaCuO$\sub$5/. In this paper, the melting temperature obtained was l120$^{\circ}C$ and propel holding time could be obtained as 20 minute and the more holding time was not effective in the J$\sub$c/ improvement as well as the formation of Y$_2$BaCuO$\sub$5/.

• International Journal of Automotive Technology
• /
• v.8 no.5
• /
• pp.651-658
• /
• 2007

This paper presents a new type of fuzzy logic-based power control strategy for fuel cell hybrid electric vehicles designed to improve their fuel economy while maintaining the battery's state of charge. Since fuel cell systems have inherent limitations, such as a slow response time and low fuel efficiency, especially in the low power region, a battery system is typically used to assist them. To maximize the advantages of this hybrid type of configuration, a power distribution control strategy is required for the two power sources: the fuel cell system and the battery system. The required fuel cell power is procured using fuzzy rules based on the vehicle driving status and the battery status. In order to show the validity and effectiveness of the proposed power control strategy, simulations are performed using a mid-size vehicle for three types of standard drive cycle. First, the fuzzy logic-based power control strategy is shown to improves the fuel economy compared with the static power control strategy. Second, the robustness of the proposed power control strategy is verified against several variations in system parameters.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.17 no.1
• /
• pp.82-89
• /
• 2014

The damage in germanium (Ge) optical window irradiated by a near-infrared continuous wave (CW) laser was studied. Laser-induced heating and melting process were surveyed, and the specific laser power and the irradiance time to melt were estimated by numerical simulation. The experiments were also carried out to investigate the macro and micro structure change on Ge window. Results showed that the surface deformation was formed by melting and resolidification process, the damaged surface had a polycrystalline phase, and the transmittance as an optical performance factor in mid-infrared region was decreased. We confirmed that an abnormal polycrystalline phase and surface deformation effect such as hillock formation and roughness increase reduced the transmittance of Ge window and were the damage mechanism of CW laser induced damage on Ge window.

• Safety and Health at Work
• /
• v.6 no.4
• /
• pp.329-337
• /
• 2015

Background: The aim of this study is to examine the prevalence of musculoskeletal complaints in Swiss operating room (OR) nurses, and to investigate how work-family conflict, work interruptions, and influence at work are related to lumbar and cervical back pain. Methods: Participants in this correlational questionnaire study included 116 OR nurses from eight different hospitals in Switzerland. Results: We found that 66% of the OR staff suffered from musculoskeletal problems. The most prevalent musculoskeletal complaints were lumbar (52.7%) and cervical pain (38.4%). Furthermore, 20.5% reported pain in the mid spine region, 20.5% in the knees and legs, and 9.8% in the hands and feet. Multiple linear regression analyses showed that work-family conflict (p < 0.05) and interruptions (p < 0.05) significantly predicted lumbar and cervical pain in OR nurses, while influence at work (p < 0.05) only predicted lumbar pain. Conclusion: These results suggest that reducing the work-family conflict and interruptions at work, as well as offering opportunities to influence one's workplace, help to promote OR nurses' health.

• Journal of Forest and Environmental Science
• /
• v.27 no.1
• /
• pp.1-15
• /
• 2011

The present study was undertaken in middle altitudinal (1500 to 2500 masl) moist temperate forest of Mandal-Chopta area in the Garhwal region of Uttarakhand, India. The aim of the present study was to assess the variation in species composition and diversity in different vegetation layers viz. herb, shrub and tree, at different altitudes. Shannon-Wiener diversity index ($\bar{H}$), $Nha^{-1}$, total basal cover per hectare (G), Simpson concentration of dominance, Pielou Equitability, species richness (SR), Margalef index, Menheink index of species richness and ${\beta}$-diversity were calculated to understand community composition. Tree G ranged from 84.25 to 35.08 $m^2ha^{-1}$ and total stem density varied from 990 to 1470 Nha-1. Total SR (herb, shrub and trees) among different forest types ranged between 31 and 58. Maximum G of herb and shrub layers was recorded at lower altitudes between 1500 and 1650 masl. ${\beta}$-diversity was higher in herb layers as compared to tree and shrub layers. Dominance-diversity curves were also drawn to ascertain resource apportionment among various species in different forest types. Values of species diversity, $\bar{H}$, $Nha^{-1}$ and G were higher in the study area as compared to similar forests growing in other parts of Uttarakhand Himalaya.

• Korean Journal of Childcare and Education
• /
• v.17 no.5
• /
• pp.105-128
• /
• 2021

Objective: This study aimed to explore the experience and meaning of pre-service early childhood teachers who practiced health promoting activities for themselves. Methods: Research participants were 115 pre-service early childhood teachers enrolled in the health education for children course at one college in G region. The reports of activity records of their eight-week long health promotion activities were collected as qualitative data followed by content analysis being implemented. Results: First, the experience of the health promoting activities the participants took part in was categorized into 'Early phase of experience: A mix of worries and anticipation, and success and failure', 'Mid phase of experience: Being motivated by physical changes and records', and 'Late phase of experience: Continuous execution through habituation.' Second, the meaning of health promotion activities the participants took part in was categorized into 'A great opportunity for introspection', 'A meaningful start of college life', and 'A valuable chance to consider desirable roles of a teacher for early childhood health education.' Conclusion/Implications: The results of this study suggest that pre-service early childhood teachers should pay close attention to their health management, and that contents that emphasize the importance of teachers' health should be included in health education.