• Journal of Aquaculture
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• v.18 no.2
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• pp.115-121
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• 2005

This study was performed to investigate the formation and mass production of resting eggs by freshwater rotifer, Brachionus calyciflorus as influenced by different aeration supplements and exchange intervals of culture water in 15-L culture vessels and 500 L culture tanks. The maximum densities and mixis rates of the rotifers were not different between experimental group exposed to air or oxygen supplements. However, the fertilization rate and formation of resting eggs of the rotifers in the air-supplemented group were significantly higher than those in the oxygen supplemented group. In the experiment concerning exchange interval of culture water, the maximum density of the rotifers and formation of resting eggs in the batch culture were significantly higher than those in the semi-continuous culture with exchange of water every day. The formation of resting eggs per Chlorella dry weight was highest in the semi-continuous culture with exchange of water every day. The resting eggs of rotifers were produced at a density of $51.8{\sim}57.9{\times}10^6$ eggs in 500-L culture tanks. In this study, the batch culture with air is an effective method for mass production of resting eggs by the freshwater rotifer, B. calyciflorus, and the efficiency of mass production of resting eggs by this rotifer was similar to that of the seawater rotifers, B. plicatilis and B. rotundiformis.

• Journal of the Korean Regional Science Association
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• v.8 no.1
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• pp.119-130
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• 1992

Many of the industrialized countries since the 1970s have been experiencing the change in the industrial structure due to technological development, that is, from Fordism to post-Fordism, or to "flexible production system". Regional development has been undergoing some changes according to the different industrial production systems. During the Fordist mass production period, the manufacturing belt was the core region of the production system. As the system shifts to flexible production system of which characteristics are veritcal disintegration, emphasis for JIT(just-in-time) delivery system, part-time and short-time labor contracts, design-intensive industries, etc, the new system requires the new production core and has produced the new industrial spaces, such as Sunbelt cities, suburbs, small-or medium-sized cities, and non-metropolitan areas. In the perspective of global system, the Fordist production system made th NICs developed, because the mass production required many unskilled and low-wage workers. As the NICs exports of manufactured goods have incredibly expanded during the 1970s, the industrialized countries have become threatened. The industriablized countries have restructured their economies and international policies. Such restructures resulted in the economic depression of the NICs. The investment pattern of the industrialized countries has changed and particularly those industries adopting the Post-Fordism have invested from the NICs to the peripheral areas of their own countries or toward the underdeveloped countries which have much lower wage workers. The investment pattern of the NICs is also undergoing some changes like from metropolitian areas to small or non-metropolitan regions. The regional development since the post-Fordist production is still going on, thus it is not possible to generalize the tendency. That could be a particular phenomenon or a stage in the long-term cycle. But the regional development in the world system since 1980s definitely shows the different pattern.t pattern.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.2
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• pp.55-61
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• 2014

Recently, the manufacturing system is being changed in a mass customization and small quantity batch production. MES is a powerful production management tool supporting production optimization from the process initiation to the final shipment. It is a production management system which plans and executes based on the production data in the shop floor. This study deployed the utilization of production data and web HMI system to process real-time production data through the collection with the shop floor. The developed system was applied to the equipment operating time and other production data could be processed with the real-time. The proposed system and web HMI can be applied for various production systems by using different logic.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.1
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• pp.13-23
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• 2002

Hydrogenation properties of Mg-Ni and Mg-Ti-Ni alloys were investigated by Pressure-Composition Isotherm (PCI) test. Those alloys were fabricated by a new alloying method, Rotation-Cylinder Method (RCM). The as-cast microstructure of Mg-10 mass% Ni alloy consists of an island-like hydride forming $\alpha$-Mg phase and the eutectic structure. After 350 cyclic tests, Mg-lO mass % Ni alloy was pulverized into fine particles of 100 nm. The fine particles, which have a large specific surface area, are highly reactive with hydrogen. However, extreme pulvehzation can separate Mg from $Mg_2Ni$ in the eutectic structure, so $Mg_2Ni$ of the eutectic structure cannot behave as a dissociated hydrogen supplier.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1603-1611
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• 2009

High-cell-density cultivation of yeast was investigated using the agricultural waste products corn steep liquor (CSL) and molasses. The Saccharomyces cerevisiae KV-25 cell mass was significantly dependent on the ratio between C and N sources. The concentrations of molasses and CSL in the culture medium were statistically optimized at 10.25% (v/v) and 16.87% (v/v), respectively, by response surface methodology (RSM). Batch culture in a 5-l stirred tank reactor using the optimized medium resulted in a cell mass production of 36.5 g/l. In the fed-batch culture, the feed phase was preceded by a batch phase using the optimized medium, and a very high dried-cell-mass yield of 187.63 g/l was successfully attained by feeding a mixture of 20% (v/v) molasses and 80% (v/v) CSL at a rate of 22 ml/h. In this system, the production of cell mass depended mainly on the agitation speed, the composition of the feed medium, and the glucose level in the medium, but only slightly on the aeration rate.

• Ocean and Polar Research
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• v.23 no.4
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• pp.395-400
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• 2001

A time-series sediment trap was deployed at 1,034 m water depth in the eastern Bransfield Strait from December 25, 1998 to December 24, 1999. About 99 % of total mass fluxes were observed during the austral summer and fall (January, February, and March). The annual total mass flux was $49.2g\;m^{-2}$. Biogenic materials including biogenic silica, organic matter, and carbonate accounted for about 67% of total particle flux, and lithogenic materials contributed about 29%. Biogenic silica was the most dominant (42% of the total flux) in these components. The next most important biogenic component was organic matter, comprising 24% of total mass flux. Calcium carbonate contributed a small fraction of total mass flux, only 0.6%. The annual organic carbon flux was $5.2g\;C\;m^{-2}$ at 1,034m water depth. The annual primary production was estimated to be $21.6g\;C\;m^{-2}$ at the sediment trap site, which seems to be highly underestimated. About 5.5% of the surface water production of organic carbon sinks below 1,034m water depth.

• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.90-96
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• 1998

The purpose of this study is to investigate the liquid culture conditions for mass production of Metarhizium anisopliae var. majus ARS 978 which is a potential microbiological pesticide. The temperature and pH range for optimal cultivation were $28^{\circ}C$ and pH 7.0, respectively. For M. anisopliae ARS 978, 1.0 %(v/v) molasses, 1.0 %(w/v) distiller's dry solubles, and 0.3 %(w/v) $CaCO_{3}$ were found to be the proper nutrients, considering cell mass, enzyme activities and spore concentration.

• Journal of the Korean Society of Costume
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• v.52 no.3
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• pp.29-47
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• 2002

이 연구에서는 대량생산의 장점인 낮은 가격대 창출과 주문생산의 장점인 고객지향을 추구하는 매스 커스터마이제이션(Mass Customization) 방식에 따른 의류제품의 생산모델을 개발하였다. 특히 체형이 매우 다양한 시기에 있어 이러한 고객지향적 의복이 더욱 필요한 중년여성들을 대상으로 하여 기성복에서 얻을 수 없는 인체적합도가 높은 의복을 생산할 수 있도록 하였다. 이 모델은 소비자 체형파악과 체형별 패턴제작의 어려움을 해결해주기 때문에 의류제조업체의 패턴제작과정을 용이하게 해주고, 모든 생산이 주문에 따라 이루어지므로 재고부담을 감소시키게 된다. 생산모델은 크게 5 단계로 나뉜다. 1 단계는 소비자가 제품에 대한 정보를 얻어 선택을 하는 단계이고, 2 단계는 소비자의 신체치수 계측 및 입력, 체형판별의 단계이다. 1) 단계에서는 이러한 내용을 포함하는 주문서를 작성하여 본사로 전송하고. 4 단계에서는 제품을 생산한다. 그리고 5 단계는 제품의 배송 단계이다. 이 연구에서 실질적으로 검증한 매스 커스터마이제이션 의류제품의 생산과정은 주문단계에서 패턴의 수정 단계까지이며, 이후의 마커제작에서 배송단계까지는 생산설비상의 문제 때문에 설명으로 제시하였다. 또한 매스 커스터마이제이션 의류제품에서 특히 중요한 단계는 고객에 대학 접근방법과 가봉 없이도 인체적합도가 높은 의복을 생산하는 것이므로 이 연구에서는 이를 중심으로 다루었다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.6
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• pp.687-692
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• 2010

The mass cultivation of Ecklonia cava Kjellman was studied as a potential biomass source for the extract industry in Korea. Experiments were conducted to investigate the optimal conditions for artificial seed production and mass cultivation of this species. Maximum growth and young thalli development in the nursery culture area occurred at 2 m depth, whereas maximum growth of thalli in the main culture area occurred at 1 m depth. Production of E. cava was between 2.6 and 3.6 kg wet wt. $m^{-1}$ after depth control and removal of fouling organism, etc. The relationship between optimal water depth for culture and underwater irradiance during the E. cava cultivation was calculated as: y = -0.718x + 8.042 ($r^2$=0.976). The growth rates achieved in this trial indicate that E. cava cultures could produce and supply sufficient biomass.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.283-287
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• 2015

Within the context of the hugely successful SAGE-LMC and SAGE-SMC surveys, Spitzer photometry observations of the Large and Small Magellanic Clouds have revealed millions of infrared point sources in each galaxy. The brightest infrared sources are generally dust producing and mass-losing evolved stars, and several tens of thousands of such stars have been classified. After photometrically classifying these objects, the dust production by several kinds of evolved stars - such as Asymptotic Giant Branch stars and Red Supergiants - can be determined. SAGE-Spec is the spectroscopic follow-up to the SAGE-LMC survey, and it has obtained Spitzer-IRS $5-40{\mu}m$ spectroscopy of about 200 sources in the LMC. Combined with archival data from other programs, observations at a total of ~1000 pointings have been obtained in the LMC, while ~250 IRS pointings were observed in the SMC. Of these, a few hundred pointings represent dust producing and mass-losing evolved stars, covering a range in colors, luminosities, and thus mass-loss rates. Red Supergiants and O-rich and C-rich AGB stars - the main dust producers - are well represented in the spectroscopic sample. This paper will summarize what we know about the mineralogy of dust producing evolved stars, and discuss their relative importance in the total dust budget.