• Journal of the Institute of Electronics Engineers of Korea CI
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• v.40 no.2
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• pp.26-37
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• 2003

An optimal software release, which is related to the development cost, error detection and correction under the various operation systems, is a critical factor for managing project. This paper described optimal software release issues to predict the release time of large switching system with the system stability point of view and evaluated a timely supply of target system, proper utilization of resources under the software reliability valuation basis. Finally, Using initial failure data, based on the exponential reliability growth model methodology, optimal release time, and analysis of failure data during the system testing and managing methodologies were presented.

• Korean Journal of Microbiology
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• v.29 no.6
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• pp.387-391
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• 1991

Methylobacterium extorquens AM1 growing on methanol as a sole source of carbon and energy was found to grow most rapidly (t$t_{d}$ =6h) at 30.deg.C in a mineral medium (pH 7.0) containing 0.5% (v/v) methanol which was agitated at 200 rpm (optimal cultivation condition). Cells grown under the optimal cultivation condition contained more spermidine, but less putrescine, than the cells grown on 2.5%(v/v) ( $t_{d}$ =8h ) or at 20.deg.C ( $t_{d}$ =8h ). Cells cultivated under the optimal condition was found to contain more spermidine than the cells grown at pH 6.0 (( $t_{d}$ =7h ) and pH 8.0 ($t_{d}$ =7.3h). the cells growing at the stationary phase under the optimal condition accumulated more spermine or putrescine than the cells growing at the same phase on 2.5%(v/v) methanol or at pH 6.0 and pH 8.0, respectively. M. extorquens AM1 grown in a medium agitated at 100 rpm ( $t_{d}$ =8.8h ) contained less spermidine and spermine than the cells grown under the optimal cultivation condition.

• Food Science and Preservation
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• v.8 no.2
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• pp.199-205
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• 2001

Red mold was isolated from meju prepared by traditional mtehod and characterized. The isolated red mold grew well on potato dextrose agar medium, In microscopic observation, it had a septum in mycelium and ellipsoidal spore. Optimal temperature and pH for growth were 30$\^{C}$ and 6.0, respectively. Enzyme activities such as protease, a-amylase and glucoamulase in ted mold were lower than those in Aspergillus oryzae. A competitive growth between red mold and Asp. oryzae was greatly affecten by cultivation temperature. The growth of isolated red mold on meju was predominant at below 30$\^{C}$ as compared with Asp. oryzae.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.4
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• pp.201-205
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• 2002

The growth conditions of Pantoea aggicmerans, a phosphate solubilizing organism, were studied In our laboratory to determine the optimal conditions. Pantoea aggionerans showed the highest growth rate at 30$\^{C}$, pH 7.0 and 2 vvm, after 50 h cultivation. A certain relationship between pH and phosphate concentration was evident when the glucose concentration in the me dium was changed. Increasing glucose concentration increased the pH buffer action of the broth. At glucose concentrations higher than the optimum concentration of 0.2 M, the cell growth was retarded. P. agglomerans consumed glucose as a substrate to produce organic acids which caused the pH decrease in the culture medium. The phosphate concentration in the medium was increased by the presence of the organic acids, which solubilized insoluble phosphates such as hydroxyapa-tite.

• Journal of environmental and Sanitary engineering
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• v.15 no.1
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• pp.34-38
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• 2000

In the screening of phenol-degrading bacteria, a strain showing good growth in media containing phenol was isolated by using enrichment culture from various sample and identified as genus Klebsiella pneumoniae. The optimal temperature and pH for cell growth of Klebsiella pneumoniae was $35^{\circ}C$ and 8.0, respectively. When phenol was added to the minimal media as a sole source of carbon and energy, the concentration of maximum and optimum for cell growth was 1,200ppm and 1,000ppm, respectively. It was observed that Klebsiella pneumoniae was able to degrade 98% of phenol (1,000ppm) after 40hr in culture. The isolated could utilize various kinds of aromatic compounds and showed good growth in presence of phenol, m-cresol and 3-methyl catechol.

• Journal of Mushroom
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• v.12 no.2
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• pp.88-95
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• 2014

Auricularia auricula-judae is an edible mushroom, which is known as wood ear, free ear, black ear mushroom, and free jelly fish. This study was carried out to obtain the basic information for mycelial culture conditions of Auricularia auriculajudae. According to colony diameter and mycelial density, the media for suitable mycelial growth were PDA and MCM. The optimum temperature for mycelial growth was $25{\sim}30^{\circ}C$. Carbon and nitrogen sources were mannose and malt extract, respectively. The optimum C/N ratio was in the range of 10 to 1 with 2% glucose. Other minor components for the optimal growth were thiamine-HCl and biotin as vitamins, succinic acid and lactic acid as organic acids, and $MgSO_4{\cdot}7H_2O$ and $KH_2PO_4$ as mineral salts.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.3
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• pp.135-142
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• 2006

Engineers are always concerned with life cycle costs for making important economic decisions through engineering action like reliability of products. Decisions during the reliability growth development of products involve trade-offs between invested costs and its returns. In order to find minimal LCC containing the reliability improvement cost, production cost, repair and replacement costs, and holding cost of spare parts for failure items we suggest in this paper relationship between development cost and sustaining cost in values of growth parameter $\beta$ of AMSAA model. This model is applied to the reliability growth program based on AMSAA model during R&D phase, the warranty activities of items and the block replacement policy for maintenance of items in avionic equipment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.607-611
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• 2016

This study was conducted to investigate the effects of different water temperatures on growth, survival, biochemical composition, and blood physiological parameters of juvenile mandarin fish Siniperca scherzeri. Feed-trained juvenile fish were subjected to four water temperatures (20, 23, 26 and 29℃) with two replicate groups. The fish were fed to apparent satiation twice daily using a formulated diet containing 55% crude protein and 6% crude lipid. After the 8-week feeding trial, survival was >96% in all groups. Weight gain and feed efficiency of fish reared at 26 and 29℃ were higher than those reared at 20℃. The protein efficiency ratio, daily feed intake, and whole body proximate composition were not affected by water temperature. These results indicate that a suitable water temperature range for optimal growth and feed efficiency of juvenile mandarin fish is 26-29℃ under these experimental conditions.

• Clinical and Experimental Pediatrics
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• v.58 no.3
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• pp.77-83
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• 2015

Relative to a fetus of the same gestational age, very low birth weight (VLBW) infants are more likely to be underfed and to undergo growth restriction during their early hospital stay. The current trend towards "early and aggressive" nutritional strategies in VLBW infants aims to overcome the early nutritional deficiency and thereby boost postnatal catch-up growth, simultaneously improving long-term neurodevelopmental outcomes. Although the minimum starting amino acid (AA) dose to prevent negative nitrogen balance is well established, the upper limit and the rate of increase of early AA doses are controversial. Most randomized controlled trials show that early and high-dose (target, 3.5 to 4.9 g/kg/day) AA regimens, with or without high nonprotein calories, do not improve long-term growth and neurodevelopment. High-dose AA supplementation may lead to early metabolic disturbances and excessive or disproportionate plasma AA levels, particularly in infants of very low gestational age. Further large studies are needed to clarify the optimal strategy for early administration of parenteral AA doses in VLBW infants.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.2
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• pp.141-149
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• 2002

Most of mechanical failures are caused by repeated loadings and therefore they are strongly related to fatigue. To avoid the failures caused by fatigue, determination of an optimal shape of a structure is one of the very important factors in the initial design stage. Shape optimization for three types of specimens, which are very typical ones in opening mode in fracture mechanics, was accomplished by the linear elastic fracture mechanics and the growth-strain method in this study. The linear elastic fracture mechanics was used to estimate stress intensity factors and fatigue lives. And the growth-strain method was used to optimize the shape of the initial shape of the specimens. From the results of the shape optimization, it was concluded that shapes of three types of specimens optimized by the growth-strain method prolong their fatigue lives very much.