• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.1 s.232
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• pp.38-44
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• 2005

Many mid-sized companies in Korean automotive industry have attempted to solve the lack of human power, to control the quality of components, to improve the production rate, and to innovate the manufacturing line. The goals of this study are to analyze the production rate of an automotive component manufacturing line using simulation software, to construct a Flexible Automation Subassembly (FAS) system and to suggest an optimized layout design using FAS line. In this research, the simulation model for manufacturing line was developed and used the realistic data of a medium sized company in Korean automotive industry. To complete this research, a simulation software 'ARENA' was used. This research analyzed the work distribution strategy and cycle time element for production flow and proposed an optimized layout to resolve line balancing problem which would bring the improved production rate.

• Bulletin of the Korean Chemical Society
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• v.14 no.6
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• pp.700-704
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• 1993

The photocatalytic alanine and hydrogen production reaction were studied by using CdS as a semiconductor photocatalysts. The rate of alanine and hydrogen production depends strongly on the temperature in heat treatment of CdS powder. In particular, the rate of alanine production, which was observed using Pt/CdS(A)-(CdS from Mitsuwa), was increased about six times than that of using Pt/CdS(B)-(CdS from Furruchi) under the same heat treatment condition at 500$^{\circ}$C. And the photocatalytic activity for alanine production using bare CdS(A) or Pt/CdS(A) was almost same with increasing temperature in heat treatment in the range of 100-600$^{\circ}$C. From X-ray diffraction data and photoluminescence spectrum, we conclude that the crystal structure changes of CdS(A) or strong interaction at interface of Pt and CdS contribute to increasing the rate of alanine and hydrogen production reaction.

• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.3071-3079
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• 2023

Helium production in the nuclear fuel matrix during irradiation plays a critical role in the design and performance of Gen-IV reactor fuel, as it represents a life-limiting factor for the operation of fuel pins. In this work, a surrogate model for the helium production rate in fast reactor MOX fuels is developed, targeting its inclusion in engineering tools such as fuel performance codes. This surrogate model is based on synthetic datasets obtained via the SCIANTIX burnup module. Such datasets are generated using Latin hypercube sampling to cover the range of input parameters (e.g., fuel initial composition, fission rate density, and irradiation time) and exploiting the low computation requirement of the burnup module itself. The surrogate model is verified against the SCIANTIX burnup module results for helium production with satisfactory performance.

• KSBB Journal
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• v.9 no.5
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• pp.443-449
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• 1994

Fermentation characteristics of Kluyveromyces fragilis CBS 1555 with Jerusalem artichoke juice, in extractive ethanol fermentation in aqueous two phase systems composed of polyethylene glycol 20000 (PEG) and crude dextran(Dx), were investigated as a function of initial sugar concentrations, concentrations of ethanol formed, or fermentation time. Both specific ethanol production rate increased with decrease in concentrations of PEG and Dx in two-phase systems. Without being related to the compositions of aqueous two-phase system, maximum specific cell growth rate and maximum specific ethanol production rate were showed in the initial sugar concentration fo $80g/\ell$ and $120g/\ell$, respectively. The inhibition effects of ethanol on specific cell growth rate and specific ethanol production rate decreased with decrease in PEG concentration and in the range of 2.5 to 5% Dx. Specific cell growth rate and specific ethanol production rate was fitted as an exponential function and a hyperbolic function, respectively, of the concentrations of ethanol formed. Overall ethanol productivity increased with increase in initial sugar concentrations, and also the required time for the maximum productivity was so. Ethanol production rate by the elapsed fermentation time showed the maximum value in the initial sugar concentration of $160g/\ell$.

• Korean Journal of Veterinary Service
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• v.23 no.3
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• pp.263-269
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• 2000

This study was carried out to set a standard of damage compensation by researching state of damage due to noises in laying and prelaying hens. Recently, there are many damage cases in chicken farms near construction site that were caused by noises of construction. Therefore disputes and complaints about economical loss have increased ceaselessly. But we have few research and report such a thing. The result have shown that the weight loss rate was ranged from 9.48% to 23.2% and mortality of laying period of hens was higher than prelaying period. Pathological findings were fatty liver, congestion and hemorrhage of intestine, erosion of proventriculus and gizzard in order of case frequency. And these signs in hens of laying period was more serious than prelaying period. Half-life rate of antibody titers against Newcastle disease and infectious bronchitis in sound stressed hens was no different compared with non-stressed hens. Egg production rate dropped from 38% to 45% according to strength of noises. Before being stressed, hens produced special, large, middle, small-size eggs in the order. But after being stressed, their egg Production rate of middle, small-size Increased while egg production rate of special, large-size decreased. Production rate of soft and broken shell eggs was 0.015% in the stressed flocks higher than 0.005% in the non-stressed flocks.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.243-245
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• 2003

The continuous fermentation process for exe-biopolymer production with Cordyceps militaris has been developed in this research. With the change of dilution rate, biopolymer production has been changed and the maximal biopolymer production has been achieved when the dilution rate was 0.0225/hr. The maximum mycelium concentration and biopolymer concentration were 8 g/L and 4.2 g/L, respectively.

• Journal of Korea Water Resources Association
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• v.48 no.1
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• pp.23-35
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• 2015

In this study, the behavior of fresh water body between the injection and production wells with the fresh water injection rate in a saline aquifer is numerically analyzed by using a three-dimensional numerical model. 8 injection wells are arranged at equidistant intervals on a concentric circle and one production well is located at the center of this circle. In the case that the fresh water injection rate is relatively small, the fresh water body around a injection well screen is not mixed with neighboring ones and is independently distributed. However, when the injection rate is increased, the size of the fresh water body is continuously increased, and the areas, where saline and fresh water among injection wells are mixed, are appeared. The mixed degree is increased as the injection rate is increased. This phenomenon is identically generated around the production well. Moreover, when the injection rate is increased, the ratio of saline water in and around the production well is decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.2
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• pp.73-78
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• 2005

Demand for the domestic hairy vetch seed production will be increased with the increasing interest of environment-friendly agriculture in Korea. This study was conducted during from 2000 fall to 2003 spring at upland field of National Institute of Crop Science in Suwon, Korea to compare wheat and triticale (TC) as stake crop of hairy vetch (HV), and to know proper seeding rates and ratios between TC and HV for the maximum HV seed production. As supporting crop of HV, TC was superior to wheat at the points of higher HV seed yield, stronger TC stalk for supporting, consistence of ripening stage of two seeds. In seeding method, row seeding was superior to broadcast seeding at the points of less lodging and higher HV seed yield. HV seed yield decreased with the increase of TC seeding rate in mixture cropping (row seeding), particularly at TC seeding rates over 5kg/10a. HV seed yield increased with the increase of HV seeding rate at the condition of TC seeding rates under 5kg/10a in spite of higher lodging of mixed crops at higher HV seeding rate due to higher HV aboveground dry matter. Maximum HV seed yield was obtained at TC seeding rate of $1\~1.5kg/10a$ as indicating HV seed yield 176kg/l0a (CV. Madison) at seeding rate of TC 1kg/10a + HV 2 kg/10a in 2001, and HV seed yield 96kg/10a (CV. Common) at seeding rate of TC 1.5kg/10a + HV 4.5kg/10a in 2003. Use of all-purpose combine harvester for harvesting and appliance for separation of mixed seeds using centrifugal force, which are prerequisite for HV seed production, was excellent in the simultaneous seeds production system of HV and TC.

• Journal of the Korean Geographical Society
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• v.50 no.2
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• pp.165-183
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• 2015

It is well known that, since the 15th century, the amount of soil loss in our country due to change in land use by human has increased more rapidly than ever before. However we cannot answer the question 'How long can the soil persist under the current rates of soil loss?', because it was difficult to quantify the soil production rate. With the advancement of accelerated mass spectrometry, the attempt to quantify rate of soil production and derive soil production function succeeded, and recently it was also applied into the Daegwanryeong Plateau. Here we introduce the principles for quantifying soil production and deriving soil production function using terrestrial cosmogenic nuclides, and then compare the soil production rates from the plateau with soil loss data after the late 20th century, and finally estimate how long the soil can persist. Averaged soil production rate since the Holocene derived from the plateau is revealed as ${\sim}0.05[mm\;yr^{-1}]$, and, however, the recent soil loss rate of intensively used farmlands at the same region is up to sixty times greater than the soil production rate. Thus, if current land use system is maintained, top soils on the cultivated lands over hillslopes especially in upland areas are expected to disappear within several decades at the earliest.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.2
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• pp.130-135
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• 2000

The characteristics of two different modes of perfusion culture, intermittent and continuous bleedings, were investigated by culturing the hybridoma cells producing von Willebrand Factor (vWF) monoclonal antibody (McAb) in a 15 L bioreactor without clogging the filter. Both culture methods exhibited similar profiles of cell density and metabolite concentrations during the culture period at the cell concentration of around 1${\times}$107 cells/mL. When the perfusion rate was increased, the intermittrnt bleeding culture showed problems of ammonia accumulation and decrease of cell viability. The continuous bleeding culture in terms of nutrient consumption and metabolite production kinetics. But the analysis of specific oxygen consumption rate showed that the specific oxygen consumption rate of intermittent bleeding culture was similar to that of exponential growth phase. The continuous bleeding culture showed higher specific oxygen consumption rate of intermittent bleeding culture. finally we proved the possibility of long-term operation of continuous bleeding culture and produced approximately 40 g of vWF McAb in a 15L bioreactor after one-month operation.