• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.1
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• pp.40-48
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• 2001

The vertical distributions of temperature, salinity, dissolved oxygen, nutrients, chlorophyll, and primary production were investigated within the top 200m water depth in the south Pacific Ocean in February,2000. The study area ($24^{\circ}-41^{\circ}S,\;81^{\circ}-168^{\circ}W$) can be hydrologically divided into two regions. Upwelling was actively occurring in the eastern region of the $110^{\circ}S$ line, meanwhile it was not active in the western region. Accordingly, chemical properties in the surface waters were different between the two regions; nitrate+nitrite and phosphate concentrations were much higher in the eastern region than in the western region due to the active upwelling, but silicate concentration was higher in the western region. Among the nutrients, the major element influencing primary production was also different between the two regions; silicon would be a major element influencing primary production in the eastern region, but nitrogen may act as a major element for primary production in the western region. Primary production showed similar values in the two regions in spite of the large differences of nutrient concentrations in the surface waters, but the total chlorophyll integrated within the 200 m water depth was almost twice as much as in the western region than that in the eastern legion.

• Journal of Wetlands Research
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• v.9 no.2
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• pp.45-55
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• 2007

Flora, actual vegetation map, distribution area by the life form, primary productivity and annual primary production by the vascular hydrophytes and hygrophytes were investigated in the Upo wetland, Changnyeong-gun, Gyeongsangnam-do, Korea from May 2005 to March 2006. The flora of Upo, Mokpo, Sajipo, Jokjibyeol, Topyeongcheon upstream, and Topyeongcheon downstream were composed of 263, 233, 244, 182, 190, and 178 taxa, respectively. The flora of total study area was 85 families, 224 genera, 287 species, 42 varieties, 4 form, or total 333 taxa. Among them, hydrophytes, hygrophytes, and others were 38, 108, and 187 taxa, respectively. The life form of the vascular hydrophytes was classified as 20 taxa of emergent plants, 6 taxa of floating-leaved plants, 5 taxa of free-floating plants, and 7 taxa of submersed plants, respectively. There were 27 plant communities including pure population, mixed population, and etc. It is also found that Trapa japonica-Ceratophyllum demersum community occupies 60.64 ha, the largest area, and Salvinia natans-Ceratophyllum demersum community 32.91 ha, Zizania latifolia community 30.05 ha, and that the area of free-floating plants was the largest as 172.6 ha(47.9%) on the basis of life form. Total annual primary production of the vascular hydrophytes and hygrophytes was 1,383.3ton. That of the emergent hydrophytes was the most as 564.1 ton(40.8%), and those of the free-floating, floating-leaved, and the submersed were 484.1 ton(34.9%), 146.7 ton(10.6%), and 1.3 ton(0.5%), respectively, and the hygrophytes was 182.1 ton(13.2%). Since most plant species are fairly adapted to the present marsh environment, bad influences and change of species composition are expected by the artificial influences on the wetland such as fragmentation, reclamation, and introduction of the exotic species. Therefore, schemes and counterplans for the conservation and preservation of the marsh are demanded.

• Proceedings of the Korea Association of Information Systems Conference
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• 1996.11a
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• pp.29-48
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• 1996

Previous studies on user training have largely focused on assessing models which describe the determinants of information technology usage or examined the effects of training on user satisfaction, productivity, performance, and so on. Scant research efforts have been made, however, to examine those effects of training by using theoretical models. This study presented a conceptual model to predict intention to use information technology and conducted an experiment to understand how training for computer skill acquisition affects primary variables of the model. The data were obtained from 32 student subjects of an experimental group and 31 students of a control group, and the information technology employed for this study was a university's electronic mail system. The study results revealed that attitude toward usage and perceived behavioral control helped to predict user intentions; outcome expectations were positively related to attitude toward usage; and self - efficacy and perceived behavioral control. The changes in those variables suggest more causal effects of user training than other survey studies.

• The Journal of Information Systems
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• v.5
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• pp.345-371
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• 1996

Previous studies on user training have largely focused on assessing models which describe the determinants of information technology usage or examined the effects of training on user satisfaction, productivity, performance, and so on. Scant research efforts have been made, however, to examine those effects of training by using theoretical models. This study presented a conceptual models to predict intention to use information technology and conducted an experiment to understand how training for computer skill acquisition affects primary variables of the model. The data were obtained from 32 student subjects of an experimental group and 31 students of a control group, and the information technology employed for this study was a university electronic mail system. The study results revealed that attitude toward usage and perceived behavioral control helped to predict user intentions ;; outcome expectations were positively related to attitude toward usage ; and self-efficacy was positively related to perceived behavioral control. The hands-on training for the experimental group led to increases in perceived ease of use, self-efficacy and perceived behavioral control. The changes in those variables suggest more causal effects of user training than other survey studies.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.8
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• pp.55-62
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• 2002

A burr has been defined as undesirable projection of material formed as the result of plastic flow from a cutting or shearing operation. It is unavoidable in all kinds of machining operation. As a result, burr makes troubles on manufacturing process due to deburring cost, quality of products and productivity. In face milling operation, burrs are formed along five edges on the workpiece. In this study, the primary interest is about exit burr The influence of the cutting parameters on the formation of exit burrs in face milling will be described experimentally. Using the results of experimental study, burr types are classified according to appearance and formation mechanism in exit burr. The burr formation mechanism in each type of burr is suggested. Data bases are developed to predict burr formation result.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.3
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• pp.445-448
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• 1999

Beef and dairy cattle are the primary ruminant livestock in Korea, but there is a serious shortage of both fresh and dry forages. Small areas of forage crops or pastures, unfavorable soil and climatic conditions, high costs for pasture production, low establishment and management technologies, etc. are the main factors limiting roughage production in Korea. To meet the roughage demand of cattle several suggestions are presented. About 845,000 ha of hilly area could be developed for pastureland. Almost the same area of paddy field, and more than 200,000 ha of reclaimed land could be used for pasture production. If all the potential area is developed for pastureland, the area could be extended to 10 times more than is presently used for pasture crops and pastureland. Productivity would be increased by developing new technologies of establishment and management. Silvo-pastoral systems should be introduced to Korea.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.50-57
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• 2006

In recent years, a mm1ber of construction robots have been developed, but few practical examples can be found on construction sites today. Nevertheless, automation and robotics are proposed as apparent solutions to problems in productivity, quality, safety, and skilled-labor availability in future construction industry. Since the early 2000s, there has been growing interest in construction automation and robotics in Korea, and significant progresses have also been made. This paper mainly describes the needs of research and development program to introduce robots on construction sites, and primary outcomes which are developed in domestic construction industry. Essential technologies required for the development of construction robots, future prospects of the technology advances, and several suggestions are also presented in this paper.

• Journal of Korean Society for Quality Management
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• v.22 no.4
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• pp.132-151
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• 1994

Quality is a critical competitive factor in today's environment because of the impact of quality on market share, productivity and costs. Especially in Korean companies, the importance of quality is heightened as they are losing price competitiveness compared to the new industrialized countries. The traditional approach to quality improvement has been focused on workers. The primary means to achieving acceptable outgoing quality has been to inspect quality by adding more inspectors and inspection stations. This is an example of quality cost that can be reduced through the preventive actions against bad quality. Quality cost is best viewed as a measure of costs specifically associated with the achievement or nonachievement of product/service quality required by customers. This paper examines the concept of quality cost, provides guidance to implementing a quality cost system, and identifies the limitations of quality cost information. These limitations are the target for future research for an efficient and effective implementation of quality cost system.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.10a
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• pp.161-166
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• 1997

Application of hot roiling oil lubrication technology was broadened to the field of RM stands of Hot Rolling Mill at Pohang works. The primary object was to improve the quality of the strip sttrface and the rolls by oil lubrication in hot rolling process. Prior to the actual field application preliminary test was conducted to evaluate the effect of hot rolling oil lubrication at RM stands. From the test, it has been found that the use of oil lubrication tends to prevent the progression of the heat cracks and thereby increases the quality of the strip surface and the wear life of the rolls. New hot rolling oil lubrication system was applied to the RM stands VSB, R1, R2, R3, R4 and edger rolls. With the introduction of a rolling lubricant, the quality of the strip surface and rolls was improved and overall roll dressing has decreased. Also there has been a improvement of productivity from the long roll life.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.169-170
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• 2000

Phytoplankton communities are generally dominated by diatoms in spring and changed to nano- and picoplankton or dinoflagellates groups in summer (Anderson et al., 1994). Many phytoplankton investigators have been used to chlorophyll a as a phytoplankton biomass, as all the phytoplankton contain (Cullen, 1982). The studies of population compositions, primary productivity, chlorophyll a of phytoplankton in the Yellow Sea have been conducted mainly in bays and estuaries with a few studies in the central area of Yellow Sea. This study is to understand the relationship between the environmental factors and cholrophyll a concentration of phytoplnakton in terms of the area and depth in the Yellow Sea and also to identify the characteristics of phytoplankton populations occurring at the most productive periods throughout the yera.