• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.557-557
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• 2003

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.2
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• pp.275-279
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• 1993

A study using dairy heifers was conducted to determine the effect of environmental temperature on heat production differing in feed intake level. The design consisted of three levels of feed intake (low, medium and high) and two environmental chamber temperature (15 and $30^{\circ}C$) with four replications in each treatment. Rectal temperature (RT), respiration rate (RR), heart rate (HR) and heat production (HP) were then measured. At the both environmental temperature, RT, RR and HR increased with the increase in feed intake level. The RT and RR also increased with the elevation of environmental temperature. The HP of $30^{\circ}C$ was significantly higher (4.8-8.9%) than $15^{\circ}C$. The estimated metabolizable energy requirement for maintenance (MEm) was higher (p<0.05) at $30^{\circ}C$ ($554.7kJ/kg^{0.75}$ d) than $15^{\circ}C$ (464.9 kJ/kgd). It was suggested that the decreasing in productive efficiency under hot environmental conditions partly associated with the increase in HP, which associated with the change in heat loss mechanism from sensible path to evaporative path.

• Journal of Microbiology and Biotechnology
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• v.22 no.6
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• pp.826-831
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• 2012

Acarbose, a pseudo-oligosaccharide, is widely used clinically in therapies for non-insulin-dependent diabetes. In the present study, S-adenosylmethionine (SAM) was added to selected media in order to investigate its effect on acarbose fermentation by Actinoplanes utahensis ZJB-08196. Acarbose titer was seen to increase markedly when concentrations of SAM were added over a period of time. The effects of glucose and maltose on the production of acarbose were investigated in both batch and fed-batch fermentation. Optimal acarbose production was observed at relatively low glucose levels and high maltose levels. Based on these results, a further fed-batch experiment was designed so as to enhance the production of acarbose. Fed-batch fermentation was carried out at an initial glucose level of 10 g/l and an initial maltose level of 60 g/l. Then, 12 h post inoculation, 100 ${\mu}mol/l$ SAM was added. In addition, 8 g/l of glucose was added every 24 h, and 20 g/l of maltose was added at 96 h. By way of this novel feeding strategy, the maximum titer of acarbose achieved was 6,113 mg/l at 192 h. To our knowledge, the production level of acarbose achieved in this study is the highest ever reported.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.147-159
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• 2024

Plutonium-238 has always been considered as the one of the promising radioisotopes for space nuclear power supply, which has long half-life, low radiation protection level, high power density, and stable fuel form at high temperatures. The industrial-scale production of ²³⁸Pu mainly depends on irradiating solid ²³⁷NpO₂ target in high flux reactors, however the production process faces problems such as large fission loss and high requirements for product quality control. In this paper, a conceptual design study of producing ²³⁸Pu in a multi-purpose high flux reactor was evaluated and analyzed, which includes a sensitivity analysis on ²³⁸Pu production and a further study on the irradiation scheme. It demonstrated that the target structure and its location in the reactor, as well as the operation scheme has an impact on ²³⁸Pu amount and product quality. Furthermore, the production efficiency could be improved by optimizing target material concentration, target locations in the core and reflector. This work provides technical support for irradiation production of ²³⁸Pu in high flux reactors.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.6
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• pp.577-582
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• 1995

Sixty ram lambs, weighting 23.5 kg, were randomly assigned in a $2{\times}3$ factorial arrangement of two dietary energy (high; 11.7 and low; 9.0 MJ ME/kg DM) and three levels of poultry offal meal supplementation (0, 5 and 10%). Lambs were fed ad libitum for 120-day before slaughter. At slaughter, half the lambs in each dietary treatment group were randomly selected for electrical stimulation of their undressed carcasses. The M. Biceps femoris pH and temperatures were monitored at 1, 3, 5, 8 and 24 h postmortem. At 24 h postmortem, the M. biceps femoris was removed from the fight side of each carcass and steaks were obtained for determination of Warner-Bratzler shear force, collagen content and collagen solubility. The results showed that temperature and pH values during the 24-h postmortem were consistently higher (p < .01) and lover (p < .01), respectively, for M. biceps femoris from lambs fed high energy diets than for those fed on low energy diets. Muscles from high energy fed lambs had lower (p < .01) shear force values and higher (p < .01) percent soluble collagen than for low energy fed lambs; total collagen content was not significantly influenced by dietary energy level. Increased the level of poultry offal meal supplementation in the diet to 10% was associated with concomitant increases (p < .01) in muscle tenderness and percent soluble collagen. Electrical stimulation (ES) of carcasses resulted in a lower shear force values for the M. biceps femoris than in non-stimulated carcasses (Non-ES); total collagen content and percent soluble collagen were not significantly affected by ES treatment.

• Journal of the Korea Safety Management & Science
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• v.16 no.2
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• pp.131-138
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• 2014

Auto part industry supplies production for auto manufacturer and after market. These company have inventory for delivery. High inventory level can be good for delivery, but cost will be increase. Low inventory level can be customer unsatisfaction for delivery late. Low inventory level also is reason of low productivity by decreasing product batch size. These article suggest model for calculation a proper inventory level and prove a effect by simulation of some company.

• Korean Journal of Computational Design and Engineering
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• v.18 no.3
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• pp.224-233
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• 2013

For the scheduling and the job assignment of the ship hull production design which is a process-based work, we suggest the simulation-based scheduling using the discrete-event-based business process simulation. First, we analyze the ship hull production design process from the perspective of a job assignment to make it into the simulation model using DEVS (Discrete Event System Specification) which is the representative modeling method for a discrete-event simulation. Based on the APIs of the open-source discrete-event simulation engine, we implement the simulation using the Groovy script. We develop the scenario generator in which the user defines detail information of the construction drawing and its member blocks, and design engineers information, and the various setting for the simulation including the job assignment strategy. We use the XML files from this scenario generator as inputs of simulation so that we can get simulation result in forms of Gantt chart without changes of the simulation model.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.321-326
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• 2000

To examine the feasibility of the long-term production of the human granulocyte colony stimulating factor (hG-CSF) using the $_{L}-arabinose$ promoter system of Escherichia coli, flask relay culture and cyclic fed-batch culture were performed. In the flask relay culture, it was found that the pismid was maintained stably up to about 170 generations in an uninduced condition, whereby the cells could also maintain the capability of expressing hG-CSF expression were maintained stably up to at least 100 generations. In contrast, in the cyclid fed-batch culture, segregational plasmid instability was observed within about 4 generations after induction, even though the cell growth and hG-CSF production reached their maximum balues, 78.0 g/l of dry cell weight and 7.0 g/l of hG-CSF, respectively. It would appear that, when compared to the flask relay culture, the high-cell density and high-level expression of hG-CSF in the cyclic fed-batch cultrure led to the segregational plasmid instability; in other words, a severe metabolic burden existe on the cells due to the high-level expression of hG-CSF. Accordingly, based on these long-term cultures, the segregational and structural plasmid instability was observed and a strategy to overcome such problems could be designed.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.3
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• pp.196-200
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• 2004

The supra molecular weight poly(〔R〕-3-hydroxybutyrate) (PH B), having a molecular weight greater than 2 million Da, has recently been found to possess improved mechanical properties compared with the normal molecular weight PHB, which has a molecular weight of less than 1 million Da. However, applications for this PHB have been hampered due to the difficulty of its production. Reported here, is the development of a new metabolically engineered Escherichia coli strain and its fermentation for high level production of supra molecular weight PHB. Recombinant E. coli strains, harboring plasm ids of different copy numbers containing the Alcaligenes latus PHB biosynthesis genes, were cultured and the molecular weights of the accumulated PHB were compared. When the recombinant E. coli XL1-Blue, harboring a medium-copy-number pJC2 containing the A. latus PHB biosynthesis genes, was cultivated by fed-batch culture at pH 6.0, supra molecular weight PHB could be produced at up to 89.8 g/L with a productivity of 2.07 g PHB/L-h. The molecular weight of PHB obtained under these conditions was as high as 22 MDa, exceeding by an order of magnitude the molecular weight of PHB typically produced in Ralstonia eutropha or recombinant E. coli.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.325-334
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• 2012

The objective of this study was to determine the roughage to concentrate (R:C) ratio with rain tree pod meal (RPM) supplementation on in vitro fermentation using gas production technique. The experiment design was a 6${\times}$4 factorial arrangement in a CRD. Factor A was 6 levels of R:C ratio (100:0, 80:20, 60:40, 40:60, 20:80 and 0:100) and factor B was 4 levels of RPM (0, 4, 8 and 12 mg). It was found that gas kinetic, extent rate (c) was linearly increased (p<0.01) with an increasing level of concentrate while cumulative gas production (96 h) was higher in R:C of 40:60. In addition, interaction of R:C ratio and RPM level affected $NH_3-N$ and IVDMD and were highest in R:C of 0:100 with 0, 4 mg of RPM and 40:60 with 8 mg of RPM, respectively. Moreover, interaction of R:C ratio and RPM level significantly increased total volatile fatty acids and propionate concentration whereas lower acetate, acetate to propionate ratios and $CH_4$ production in R:C of 20:80 with 8 mg of RPM. Moreover, the two factors, R:C ratio and RPM level influenced the protozoal population and the percentage of methanogens in the total bacteria population. In addition, the use of real-time PCR found that a high level of concentrate in the diet remarkably decreased three cellulolytic bacteria numbers (F. succinogenes, R. flavefaciens and R. albus). Based on this study, it is suggested that the ratio of R:C at 40:60 and RPM level at 12 mg could improve ruminal fluid fermentation in terms of reducing fermentation losses, thus improving VFA profiles and ruminal ecology.