• International Journal of Advanced Culture Technology
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• v.7 no.4
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• pp.56-62
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• 2019

Recently, research using artificial neural networks has further expanded the field of neural network optimization and automatic structuring from improving inference accuracy. The performance of the machine learning algorithm depends on how the hyperparameters are configured. Open-source hyperparameter optimization software can be an important step forward in improving the performance of machine learning algorithms. In this paper, we review open-source hyperparameter optimization softwares.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.995-1002
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• 2018

Hairy root culture of ginseng is industrially prospected because the cultivation period of ginseng is relatively long. In this study, the effect of medium concentration and sucrose concentration on hairy root culture of ginseng was evaluated. The optimization of ginseng hairy roots transformed by Agrobacterium rhizogene were performed liquid medium. The MS(Murashinge & Skoog basal medium) concentration was selected with 1/2 strength MS and the optimal sucrose concentration was determined at 2-3%(w/v). At the optimum culture condition, The yield (the ratio of weight of grown hairy root cultures to weight of fresh ginseng hairy roots) and production rate of ginseng root were 19.42 times and 5.73 g/l-day. The major ginsenosides were Rb group, Re and Rg1. The produced total ginsenoside content in the solid medium was 9.87 (mg/g) and increased 1.34 times in the liquid medium (13.23 mg/g). In solid culture, the contents of ginsenosides Rb, Re and Rg1 were 2.14, 3.65 and 1.87 mg/g, respectively. In liquid culture, the contents of ginsenosides Rb, Re and Rg1 were 3.54, 4.12 and 2.63 mg/g, respectively.

• The Korean Journal of Food And Nutrition
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• v.1 no.2
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• pp.31-36
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• 1988

An adaptive on-line optimization method has been applied to test the ability to maximize the cellular productivity of a continuous methylotroph culture system which was simulated by a variable yield Monod-type model. Optimum dilution rate and productivity were successively obtained and maintained at all times by the algorithm that utilizes steepest descent technique as optimization method and recursive least-square method with forgetting factor as dynamic model identification.

• Archives of Pharmacal Research
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• v.19 no.3
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• pp.173-177
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• 1996

The Pneumococcus, Streptococcus pneumoniae, has an ample polysaccharide (PS) capsule that is highly antigenic and is the main virulence factor of the organism. The capsular PS is the source of PS vaccine. This investigation was undertaken to optimize the culture conditions for the production of capsular PS by type 4 pneumococcus. Among several culture media, brain heart infusion (BHI) and Casitone based medium were found to support luxuriant growth of pneumococcus type 4 at the same level. Therefore in this study, the Casitone based medium was used to study optimization of the culture condition because of BHI broth's high cost and complex nature. The phase of growth which accomodated maximum PS production was exponential phase. Concentrations of glucose greater than 0.8% did not enhance growth or PS production. Substitution of nitrogen sources with other resources or supplementation of various concentrations of metal ion (with the exception of calcium, copper, and magnesium ions) had adverse effects on growth and PS production. On the other hand, low level aeration and supplementation of 3 mg/l concentration of asparagine, phenylalanine, or threonine were beneficial for increased PS production. The synergistic effect of all the favorable conditions observed in pneumococcal growth assays provided a two-fold cumulative increase in capsular PS production.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1139-1146
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• 2007

Cultures of Saccharomyces cerevisiae were subjected to the effect of PEF (pulse electric field) and a source of selenium. The culture period after which yeast cells were subjected to PEF treatment was optimized, as was the duration of the exposure. Optimization of the nutrient medium composition in S. cerevisiae cultures resulted in an over 1.8-fold increase in selenium accumulation with relation to cultures on the initial substrate. Optimization of the pH value and of culture duration resulted in selenium accumulation increase by approximately 78%. A significant correlation was found between the accumulation of selenium in yeast cells and its concentration in the culture substrate. The highest accumulation of selenium in the biomass of yeast, approx. $240\;{\mu}g/g$ d.m., was obtained after 15-min exposure to PEF on a 20-h culture. An approx. 50% higher content of selenium in cells was recorded, as compared with the control culture without the application of PEF.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.66-71
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• 2005

Doxorubicin is a clinically important anticancer polyketide compound that is typically produced by Streptomyces peucetius var. caesius. To improve doxorubicin productivity by S. peucetius, a doxorubicin pathway-specific regulatory gene, dnrI, was cloned into a high-copy-number plasmid containing a catechol promoter system. The S. peucetius containing the recombinant plasmid exhibited approximately 9.5-fold higher doxorubicin productivity compared with the wild-type S. peucetius. The doxorubicin productivity by this recombinant S. peucetius strain was further improved through the optimization of culture media composition. Based on the Fractional Factorial Design (FFD), cornstarch, $K_2HPO_4$, and $MgSO_4$ were identified to be the key factors influencing doxorubicin productivity. The Response Surface Method (RSM) results based on 20 independent culture conditions with varying amounts of key factors predicted the highest theoretical doxorubicin productivity of 11.1 mg/l with corn starch of 46.33 g/l, $K_2HPO_4$ of 4.63 g/l, and $MgSO_4$ of 9.26 g/l. The doxorubicin productivity of the recombinant S. peucetius strain with the RSM-based optimized culture condition was experimentally verified to be 11.46 mg/l, which was approximately 30.8-fold higher productivity compared with the wild-type S. peucetius without culture media optimization.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.199-202
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• 2000

Optimization of submerged culture conditions for the production of exo-biopolymer from Paecilomyces japonica was studied. Maltose, yeast extract and potassium phosphate were the most suitable sources of carbon, nitrogen, and inorganic salt, respectively, for both production of the exo-biopolymer and mycelial growth. The optimal culture conditions in flask culture were pH 5.0, $25^{\circ}C$ and 150 rpm in a meidum containing of 30 g maltose, 6 g yeast extract, 2 g polypeptone, 0.5 g $K_2HPO_4$, 0.2 g $KH_2PO_4$, 0.2 g $MnSo_4\;{\cdot}\;5H_2O$, 0.2 g $MgSO_4\;{\cdot}\;7H_2O$ in 1-L distilled water. Exo-biopolymer production and mycelial growth in the suggested medium were significantly increased in a 2.5-L jar fermentor, where the maximum biopolymer concentration was 8 g/1.

• International Journal of Computer Science & Network Security
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• v.21 no.4
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• pp.80-83
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• 2021

The article analyzes and shows the rapid development information and telecommunication technologies, and their capabilities are becoming unprecedented for human development, effective solutions to many professional problems. The analysis of information and communication technologies of education used in higher educational institutions of Ukraine confirmed that for the effective use of special teaching methods, as well as software and technical teaching aids, it is necessary to have a trained teaching staff and students.

• Journal of Microbiology and Biotechnology
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• v.17 no.12
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• pp.1996-2004
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• 2007

In this study, the optimization of culture medium using a Sterigmatomyces elviae mutant was investigated using statistical analysis to increase the cell mass and lactosucrose ($^4G-{\beta}$-D-galactosylsucrose) production. In basal medium, the cell mass and lactosucrose production were 4.12 g/l and 140.91 g/l, respectively. However, because of the low cell mass and lactosucrose production, optimization of culture medium was carried out to increase the cell mass and lactosucrose production. Culture media were optimized by the S. elviae mutant using analysis of variance (ANOVA) and response surface methodology (RSM). Central composite designs using RSM were utilized in this investigation. Quadratic models were obtained for cell mass and lactosucrose production. In the case of cell mass, optimal components of the medium were as follows: sucrose 1.13%, yeast extract 0.99%, bactopeptone 2.96%, and ammonium sulfate 0.40%. The predicted maximum value of cell mass was about 5.20 g/l and its experimental value was 5.08 g/l. In the case of lactosucrose production, optimal components of the medium were as follows: sucrose 0.96%, yeast extract 1.2%, bactopeptone 3.0%, and ammonium sulfate 0.48%. Then, the predicted maximum value of lactosucrose production was about 194.12 g/l and the corresponding experimental value was about 183.78 g/l. Therefore, by culturing using predicted conditions, the real cell mass and lactosucrose production increased to 23.3% and 30.42%, respectively.

• Journal of applied mathematics & informatics
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• v.24 no.1_2
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• pp.387-397
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• 2007

According to the controllability of pulse times and the amount of jumps in the states at these times in the process of fed-batch culture producing 1,3-propanediol, this paper proposes a terminal optimal control model, whose constraint condition is the nonlinear impulsive delay system. The existence of optimal control is discussed and an optimization algorithm which is applied to each subinternal over one cycle for this optimal control problem is constructed. Finally, the numerical simulations show that the terminal intensity of producing 1,3-propanediol has been increased obviously.