• Proceedings of the Korean Information Science Society Conference
• /
• 2000.04a
• /
• pp.181-183
• /
• 2000

분산 시스템 개발을 위해 사용되는 패러다임(paradigm)의 수행능력은 여러 요소들을 종합하여 고려하여 평가해야 한다. 분산시스템 개발 시 사용되는 대표적인 패러다임으로 클라이언트/서버(client-server) 구조의 RPC(Remote Procedure Call)가 있다. 또한 최근 들어서는 이동성(mobility)과 지능성(intelligence) 이라는 특성을 갖고 네트워크 부하(network load)를 감소시킬 수 있는 이동 에이전트에 대한 요구도 증가하고 있다. 그러나 이동 에이전트를 이용하여 개발한 분산 시스템이 기존의 접근 방식에 비해 성능이 좋은 지의 여부는 아직도 의견이 분분하다. 또한 분산 시스템의 성능은 어떤 패러다임을 쓰는가 뿐 아니라, 선택된 패러다임의 수행 패턴에 의해서도 많은 영향을 받는다. 본 논문에서는 RPC 와 이동 에이전트 그리고 locker 패턴이 적용된 이동에이전트의 수행을 평가하기 위한 수행 평가 모델과, 이 모델을 기초로 하는 분산 시스템 개발을 위한 수행 패턴 결정 알고리즘을 제시하고자 한다.

• Journal of Agricultural Extension & Community Development
• /
• v.18 no.3
• /
• pp.435-483
• /
• 2011

This paper was to study characteristics of school types based on classification of rural areas. This study tried to provide basic data for implementing the development of rural education policy for the community unit by classifying and analyzing administrative districts. For the purpose, the researcher carried out literature reviews and selected three schools considering the gaps in size and location of rural community. The researcher interviewed teachers and parents, to gather information about rural education, and conducted participant observation on educational activities. As a result, this study showed each rural school has its own distinct characteristics by the school types corresponding to each rural community. Characteristics with school types were influenced by school location, possible migration into the cities, possible opportunities of private tutoring, school size, social class distribution, socio-economic status, dwelling pattern of school teachers. In conclusion, it is important that the educational policies for rural area consider the different characteristics of rural schools.

• Ocean and Polar Research
• /
• v.39 no.4
• /
• pp.257-267
• /
• 2017

Although Pacific mackerel (Scomber japonicus) is an important commercial species in Korea, its recruitment mechanism remains largely unknown. Diel vertical positioning of larvae in the water column, which is affected by their specific gravity and the surrounding water density, may help to provide an understanding on recruitment success through predator avoidance and prey availability. The specific gravity measurement on Pacific mackerel eggs and larvae would seem to be essential information necessary to learn about the transport process from spawning to nursery grounds, and consequently the recruitment success. Eggs were artificially fertilized, and larvae were fed with rotifer when their mouths opened 3-4 days after hatching. We conducted the experiment using a density gradient water column to measure the ontogenetic changes in specific gravity from fertilization to 10 days after hatching. Egg specific gravity was stable during most of the embryonic period, but a sudden increase to $1.0249g\;cm^{-3}$ happened just before hatching. However, the specific gravity of newly hatched larvae was much lighter ($1.0195g\;cm^{-3}$), and specific gravity tended to increase continuously after hatching. Comparison of specific gravity with seawater density reveals that eggs and newly hatched larvae can float in the surface layer of the ocean. For the later period of the experiment, the specific gravity showed a cyclic diel pattern: the highest in the evening while the lowest at dawn. The fullness of larval stomach may be responsible for the observed differences in specific gravity, because stomach fullness was lower (40-60%) at midnight, and higher (80-85%) in evening. The diel pattern of specific gravity might provide clues regarding how larvae match the diel vertical migration of prey organisms.

• Journal of Ginseng Research
• /
• v.22 no.3
• /
• pp.168-172
• /
• 1998

Systematic electrophoretic analysis of alcohol-soluble proteins and salt-soluble proteins of 247 Panax ginseng (P.g) and Panax quinquefolium (P.q) germplasms seed was carried out on an improved lactate-polyacrylamide gel electrophoresis, a method with high resolving power, good reproducibility and stability. The electrophoregrams of proteins, according to their migration rate, were classified into four groups such as ${\alpha}$, ${\beta}$, ${\gamma}$ and $\omega$ for the alcohol-soluble proteins and three such as I, II and III for the salt-soluble ones. Panax ginseng or Panax quinquefolium had their own unique band pattern distinguishable from each other, regarding as their specific "fingerprint". In this study, 3 of 168 (1.8%) P.g germplasms and 1 of 79 (1.3%) P.q germplasms had their own unique band pattern, showing that P.g and P.q germplasms have poor genetic diversity in species. The band patterns of dry seed and stratified seed (embryo rate=60%) were basically the same. The band number of the F, hybrid of p.gx p.q was exactly equivalent to the number of the common bands plus the specific bands of the two parents, indicating that the difference of band patterns was a genetic trait con- trolled by the nuclear genes. The electrophoregram of F1 of P.g x P.q could be predicted by that of the two parents and the band pattern of the F1 hybrids could be demnonstrated by that of the mixed seed extract from the two parents.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.16 no.4
• /
• pp.229-235
• /
• 2014

This study conducted a research on burn-out printing convergence technology for cellulose blend knit fabrics. Printing technology, which forms color pattern on the fabric, can be generally classified into four according to printer or printing method, e.g. screen printing, roller printing, rotary printing, digital printing. However, these printing methods are flat in design or pattern, which have limitation to overcome monotonousness of fabric, so that recently burn-out process method, which expresses three-dimensional pattern effect by treating chemical on the surface of fabric as the method to appeal its esthetics to the customers. Particularly, in case of cellulose/polyester composite material, first, it is proceeded in 2 processes, by dyeing cellulose or polyester fabric and burning out cellulose fabric, in this process, due to pollution caused by disperse dye migration, color of polyester fabric part could be discolored, which has high falt risk. This research considered coloring burn-out technique, which simultaneously proceed dyeing and burn-out by reducing dyeing and burn-out process to 1 stage, which were proceeded in 2 stages previously. As the research result, it was confirmed that reasonable depth of roller was 0.04~0.06mm in roller printing process, heat treatment condition of burn-out far-infrared radiation was $185^{\circ}C{\times}30m/min$. Color fastness to washing was confirmed to be 4-5 grade, color fastness to rubbing, 3-4 grade, color fastness to light, 4 grade. Also, it was confirmed that energy reduction effect appeared 38.19%, in case of energy cost per yard compared to the existing production, also, 19.74%, in case of production cost.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2003.03a
• /
• pp.68-68
• /
• 2003

최근의 전자부품은 고밀도 고집적화 됨에 따라 여러 가지 문제점들이 발생되고 있다. 그 중 부품이 실장되는 부분에 사용되는 솔더나 전기적 회로를 구성하는 패턴간에 금속 이온 마이그레이션(Metallic Ion Migration)이 발생하여 전기적 단락(Short)를 유발함으로써 전자제품의 치명적 고장을 유발한다. 본 연구는 이온 마이그레이션 현상을 물방울시험(Water Drop Test)을 통하여 재현함으로써 발생 메카니즘을 확인하여 발생원인을 직접적으로 관찰하고, 각 종 패턴의 거리 및 전압에 따른 발생속도의 차이를 조사하기 위하여 수행되었다. 이러한 실험을 위하여 콤 패턴(Comb Pattern)의 FR-4 재질 인쇄회로기판(PCB : Printed Circuit Board)을 사용하였으며, 사용된 전극재질로는 Cu, SnPb, Au를 사용하였고, 패턴간 거리는 0.5, 1.0, 2.0mm의 3가지 종류로 구분하였다. 또한 패턴간에 인간 된 전압은 6.5V, 15V를 인가한 후 마이그레이션이 발생되는 시간을 측정하였다. 이러한 실험으로부터 다음과 같은 결론을 얻었다. (1) 6.5V의 인가전압에서는 Cu 패턴이 대체적으로 가장 빠르게 마이그레이션이 발생하였으며, 다음으로 Au가 발생하였고, Cu와 SnPb의 발생시간은 대체적으로 근사한 값을 나타내었다. 이것은 비슷한 평형전위를 갖는 재료는 마이그레이션 발생시간이 유사하게 나타나며, 높은 (+)전위를 갖을수록 발생시간이 지연됨을 알 수 있다. (2) 15V를 인가하였을 때 패턴간격이 0.5mm인 경우 Cu, Au, SnPb의 순으로 나타났으며, 1.0mm는 SnPb, Cu, Au, 2.0mm인 경우는 SnPb, Au, Cu의 순으로 마이그레이션이 발생하였다. 인가전압이 높은 경우 초기 발생에는 큰 차이가 없지만 수지상이 발생 후 성장하는데 많은 영향을 미치는 것으로 보인다. 이것은 초기 수지상의 형성에 큰 영향을 미치는 것은 재료의 평형전위에 의한 값이 좌우하지만, 수지상이 일정길이 이상 형성된 이후에는 성장속도가 평형전위에 따른 값과는 다소 다르게 나타남을 알 수 있다.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.48 no.4
• /
• pp.401-414
• /
• 2012

Distribution pattern and fishing conditions of sandfish, Arctoscopus japonicus in the East Sae were explored using catch and catch per unit effort (CPUE) by eastern sea Danish seine and coastal gill net fisheries from 2004 to 2008. A. japonicus was one of major target species for the eastern sea Danish seine and coastal gill net fisheries in the East Sea, which were caught from April to October for the eastern Danish seine, and from October to December for the coastal gill net, respectively. In recent, the distribution and centroid of fishing ground moved northward, as seawater temperature increased. The species spawned in the coastal areas of Gangwon, northern East Sea, during winter, started to move to deeper water after spawning from spring, extended widely from Gangwon to Ulsan, southern East Sea, during summer, and migrated back to the spawning ground off Gangwon during autumn.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.44 no.6
• /
• pp.709-716
• /
• 2011

To investigate the distribution and migrations of sea turtles occurring in Korean waters, an adult female green sea turtle Chelonia mydas was tagged with a satellite transmitter and released at Busan in October 2009. The confirmation was made for the first time that the released green sea turtle migrated back to Korea after visiting Jeju Island and Japan for approximately 9 months. The green sea turtle spent the winter in Jeju and Japan because of low water temperatures in the East Sea and South Sea during winter months, which were not suitable for turtle survival. Compared with an immature green sea turtle that was released at Jeju Island, the adult green showed a markedly different migration pattern, suggesting that juvenile and adult greens move differently because of their peculiar life cycle and their stage of maturity, in addition to responses to temperature changes. Additional satellite tracking with increased representation of species, sexes and sizes of turtles, and regions is required to gather information on the distribution and movements of sea turtles in Korean waters.

• Journal of Veterinary Clinics
• /
• v.34 no.2
• /
• pp.146-151
• /
• 2017

Six major outbreaks of highly pathogenic avian influenza (HPAI) occurred from 2003 to 2016 in Korea. Epidemiological investigations of each outbreak revealed that migratory birds were the primary source of the HPAI virus. During the last five years, the geographic transmission pattern of domestic HPAI seems to have extended from local to nationwide; therefore, it is necessary to identify specific locations in which poultry farms are at elevated risk for HPAI outbreak to enable targeted surveillance and other mitigation strategies. Here, a geographical information system (GIS)-based analysis was used to identify geographic areas at high risk for future HPAI incidents in Korea based on historical outbreak data collected between December 2003 and April 2016. To accomplish this, seven criteria were used to identify areas at high-risk for HPAI occurrence. The first three criteria were based on defined spatial criteria buffering of 200 bird migration sites to some defined extents and the historical incidence of HPAI outbreaks at the buffering sites. The remaining criteria were based on combined attribute information such as number of birds or farms at district levels. Based on the criteria established for this study, the most-likely areas at higher risk for HPAI outbreak were located in Chungcheong, Jeolla, Gyeonggi, and Gyeongnam provinces, which are densely populated poultry regions considered major poultry-production areas that are located along bird migration sites. The proportion of areas at risk for HPAI occurrence ranged from 4.5% to 64.9%. For the worst criteria, all nine provinces, including Jeju Island, were found to be at risk of HPAI. The results of this study indicate that the number of poultry farms at risk for HPAI outbreaks is largely underestimated by current regulatory risk assessment procedures conducted for biosecurity authorization. The HPAI risk map generated in this study will enable easy use of information by policy makers to identify surveillance zones and employ targeted surveillance to reduce the impact of HPAI transmission.

• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.12
• /
• pp.1703-1712
• /
• 2015

The in vitro maturation (IVM) efficiency of porcine embryos is still low because of poor oocyte quality. Although brilliant cresyl blue positive (BCB+) oocytes with low glucose-6-phosphate dehydrogenase (G6PDH) activity have shown superior quality than BCB negative (-) oocytes with high G6PDH activity, the use of a BCB staining test before IVM is still controversial. This study aimed to shed more light on the subcellular characteristics of porcine oocytes after selection using BCB staining. We assessed germinal vesicle chromatin configuration, cortical granule (CG) migration, mitochondrial distribution, the levels of acetylated lysine 9 of histone H3 (AcH3K9) and nuclear apoptosis features to investigate the correlation between G6PDH activity and these developmentally related features. A pattern of chromatin surrounding the nucleoli was seen in 53.0% of BCB+ oocytes and 77.6% of BCB+ oocytes showed peripherally distributed CGs. After IVM, 48.7% of BCB+ oocytes had a diffused mitochondrial distribution pattern. However, there were no significant differences in the levels of AcH3K9 in the nuclei of blastocysts derived from BCB+ and BCB- oocytes; at the same time, we observed a similar incidence of apoptosis in the BCB+ and control groups. Although this study indicated that G6PDH activity in porcine oocytes was correlated with several subcellular characteristics such as germinal vesicle chromatin configuration, CG migration and mitochondrial distribution, other features such as AcH3K9 level and nuclear apoptotic features were not associated with G6PDH activity and did not validate the BCB staining test. In using this test for selecting porcine oocytes, subcellular characteristics such as the AcH3K9 level and apoptotic nuclear features should also be considered. Adding histone deacetylase inhibitors or apoptosis inhibitors into the culture medium used might improve the efficiency of IVM of BCB+ oocytes.