• Ocean and Polar Research
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• v.26 no.2
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• pp.265-272
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• 2004

This study was conducted to investigate the community structure and distributional pattern of meiobenthos in the deep-sea bottom of the Clarion-Clipperton Fracture Zone of northeastern Pacific during July 2001. Examination of sediment samples collected on the eight survey station showed that there were 10 different types of meiobenthos. The most abundant meiobenthic animals were nematodes in all stations. Sarcomastigophorans, benthic harpacticoids were next abundant meiobenthos. Vertical distribution of meiobenthic animals showed the highest individual numbers in the surface sediment layers of 0-1 cm depth and showed more steep decreasing trend as sediment gets deeper on the stations of high latitude located in $16-17^{\circ}N$. Horizontal distribution of meiobenthic animal in the study area within CCFZ showed high densities of meiobenthos at the stations had few manganese nodules on their sediment surface in the site of low latitude. For size distribution analyses showed that animals which fit into the sieve mesh size of 0.063 mm were abundant.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.426-437
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• 2004

To understand the phytoplankton community in adjacent waters of Ulchin nuclear power plant (UNPP), abundance and the size fractionated $chl-\alpha$ concentrations were evaluated through seasonal interval sampling from April 2003 to February 2004. A total of 211 different phytoplankton species was observed and mean abundance of phytoplankton in each study period ranged from 244,286 to 1,221,779 cells $L^{-1}$. The contributions of microplankton $(>20\mu{m})$ to total phytoplankton abundance ranged from 42.5 to 83.6% (average 66.1%) and those of nanoplankton $(>20\mu{m})$ ranged from 16.4 to 57.5% (average 33.9%). Total chl-$\alpha$ concentrations of phytoplankton ranged from 0.52 to $2.26\mu{g}\;L^{-1}$. The contribution of chl-$\alpha$ concentrations of microplankton was higher than that of nano- and picoplankton through the study period with exception of July 2008. The results of abundances and $chl-\alpha$ concentrations suggest that microplankton has an important role in adjacent waters of UNPP. The diminution of abundances and $chl-\alpha$ concentrations of phytoplankton was observed after passage through the cooling water system, but it was gradually recovered by mixing with the ambient waters. Our results suggested that the influence of thermal discharges on phytoplankton should be restricted within narrow limits around outlet area of thermal effluents.

• Korean Journal of Materials Research
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• v.14 no.1
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• pp.19-27
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• 2004

Metallurgical and mechanical experiments were performed to explain unexpected surface cracks encountered in fabricating ground rolled-billet of Fe-Cr-Al alloys at room temperature. The toughness of these alloys containing between 220 and 236 ppm (C+N) has been assessed using notched-bar impact tests. According to our results, with a larger grain size, a higher interstitial content of (C+N) or a smaller size of precipitates, ductile to brittle temperature(DBTT) increased and absorbed energy decreased at room temperature. These results suggest that the surface cracks at room temperature stem from a poor resistance to brittle fracture, due to dislocation movement by the finely dispersed carbides within grains under the condition of higher (C+N) content.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.4
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• pp.342-347
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• 2008

Mortality and growth rate of the soft coral, Dendronephthya gigantea, from Jejudo Island on the southern coast of Korea were investigated from February 2003 to October 2004 using SCUBA diving. 48 individuals with variable sizes of D. gigantea of the depth of 15m were tagged with flagging tapes and plastic films, and then monitored with two month intervals. The average mortality of two-month term for the study period was 50.4%, with the peak of 84.6% during the summer storms in August - October 2003. About the size class mortality, individuals of size class I(${\leq}$10 cm) showed the highest mortality, followed by size class III(>20 cm) and size class II(10 cm-20 cm). Growth rate did not show a seasonal pattern. For growth in length, individuals of D. gigantea grew about 3cm in average for two-month period, with a maximum growth of 6.4 cm which occurred in August - October 2003. For growth in diameter, individuals grew about 0.3 cm for 2 month term, with a maximum of 1.4cm in April - June 2004. Individuals of size class I usually grew faster than those of larger size classes. D. gigantea population in Jejudo Island was strongly affected by summer storms, which was due to annual event of summer typhoon. Never the less, it appears that the local population can be maintained by fast growth of the juvenile stage and active recruitment to compensate the high mortality caused by the summer disturbance.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.125-130
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• 2004

It is not difficult to see the road repairing. There are many and various machines that can crush road surface. The efficiency and power of the machine depend on crushing head-shape, crushing interval, crushing load, crushing stress, machine's dropping height and roller's kind. The objective of this study is to select the optimal model among ten models of crushing machine with constraints such as crushing depth, variation, and crushed particle size. The data for this study are chosen from the site of construction in Kangnung during three months ($2004.\;6.\;1\;\sim\;2004.\;8.\;31$). The provided methodology in this paper will be fruitful not only for the selection of crushing machine but also for the aspects of construction period, cost, work efficacy according to the condition from the various sites of construction.

• KIEE International Transactions on Electrophysics and Applications
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• v.4C no.2
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• pp.68-72
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• 2004

The performance of copper-tungsten for electrodes used in an ultra high voltage interruption system was evaluated by means of an interruption test, which requires a large-scale apparatus and high cost. In this study, prior to the interruption test, the characteristics of a Cu-W electrode were estimated through the DC arc test, which is a simple, low cost procedure. The DC arc characteristics of a 20wt%Cu-80wt%W electrode were investigated with the change of tungsten powder size distribution and the addition of nickel. In specimens containing a high volume fraction of large sized tungsten particles, the relative density and hardness of sintered Cu-W electrodes increased while the electrical conductivity and the DC arc resistance decreased. Furthermore, the relative density became enhanced with the increase of the amount of nickel while the hardness and electrical conductivity diminished and the DC arc resistance worsened.

• Journal of the Ergonomics Society of Korea
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• v.25 no.2
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• pp.71-76
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• 2006

The goal of this research is to analyze the Korean anthropometric data collected through Project "Size Korea" by ATS from 2003 to 2004, to extract the characteristics for each age and sex group, and to establish an extensive reference for designers of related products. The result shows that the characteristics of Korean anthropometric data have the different ratio and distribution among mutually related factors for different age and sex. Especially, the difference between two groups, those in their twenties and those in their fifties and above, are huge, indicating that there are drastic changes in the data for recent decades. The result of this research can be used for the design of furniture, clothes and workplace, where there are different target ranges for specific age and sex.

• Journal of Korean Society of Forest Science
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• v.94 no.2 s.159
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• pp.117-120
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• 2005

This study was conducted to estimate population size and investigate habitat characteristics for the conservation and management of Amur goral Nemorhaedus caudatus raddeanus in DMZ (Demilitarized Zone) of Gangwon Province in South Korea from November 2003 to May 2004. The Amur gorals counting were carried out by assistance of military soldiers who guards the southern boundary of DMZ. Four hundred sixty individuals were estimated as total population size in DMZ of Gangwon Province. Deciduous forest, rocky area and coniferous forest were dominant land cover types in habitat of Amur goral. DMZ and its vicinity of Gangwon Province are very important areas for the conservation of this species. It is needed to establish management plan for the conservation of Amur goral and their habitats in DMZ.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.1
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• pp.153-166
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• 2010

The study analyzes the lower-trunk sizes of 7-12 year old elementary school boys and compares sizes with boys, juniors, and men for analyzing and image fit. For the study, the data of SizeKorea (2004) was analyzed. Waist, hip, and the ratio of hip-thickness to hip-width were significantly different between age groups as well as between boys, juniors, and men. In the same height group, over 145cm boys had bigger waist than juniors and smaller waists than men. Therefore, the difference of waist size and the length of leg could cause the dissatisfaction of the pant fit when tall and plump boys chose a corresponding pants size to individual height or waist. The hip-thickness of body and pants patterns were compared in the analysis of the ease of hip-thickness. Tall and plump boys will feel discomfort in the crotch area because of the insufficiency of the hip-thickness of pants. Therefore, the amount of crotch extension of individual pants should be calculated by hip size instead of using the fixed amount. The reference sizes for discriminative pants for tall and plump boys were analyzed for a better fit.

• Journal of the Ergonomics Society of Korea
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• v.23 no.2
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• pp.1-12
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• 2004

The purposes of this study were to investigate the relationship between anthropometric data of foot and other body sizes. to categorize the foot shape of elementary school boys and to find out determinant factors related the foot that enable us to deduce the foot shape and size for the design of more comfortable shoes. Subjects of this study were 249 elementary school boys of age ranged from 6 to 11 residing Seoul and lncheon area. Anthropometric sizes were measured with the direct measurement method using Martin scales and the indirect measurement method using digital photos. Pearson's correlation, factor analysis. cluster analysis. analysis of variance, post-hoc test, and cross tabs were performed for statistical analysis of the data by SPSS program. From the investigation on the relationship between foot-related items and body items, most items of foot measure were significantly related to body size items. However, angle of the foot did not related to other body sizes although other height items and mass items of the foot did have relationships with other body sizes. Results of ANOVA indicated there were significant differences in foot-related items except for items of foot angle and all body anthropometric items by subjects' age. This implicates big toe angle, little toe angle and foot ratio factors are required in sizing shoes besides foot length. On the basis of cluster analysis using factor scores. three different foot shapes were categorized. Type 1 was large and wide foot, Type 2 was small and narrow foot with large toe angle. and Type 3 was medium foot with no deformity on big toe. These three groups show significant differences in almost all measurement items. However, Rorher index and foot angle didn't show any significant differences among groups. This implicates the foot shape can be a determinant of shoe size.