• Journal of Life Science
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• v.18 no.12
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• pp.1764-1770
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• 2008

The goal of this study is to increase production of astaxanthin in recombinant Escherichia coli by engineered isoprenoid pathway. We have previously reported structural and functional analysis of the astaxanthin biosynthesis genes from a marine bacterium, Paracoccus haeundaensis. The carotenoid biosynthesis gene cluster involved in astaxanthin production contained six carotenogenic genes (crtW, crtZ, crtY, crtI, crtB, and crtE genes) and recombinant E. coli harboring six carotenogenic genes from P. haeundaensis produced 400 ${\mu}g$/g dry cell weight (DCW) of astaxanthin. In order to increase production of astaxanthin in recombinant E. coli, we have cloned 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (lytB), farnesyl diphosphate (FPP) synthase (ispA), and isopentenyl (IPP) diphossphate isomerase (idi) in the isoprenoid pathway from E. coli and coexpressed these genes in recombinant E. coli harboring the astaxanthin biosynthesis genes. This engineered E. coli strain containing both isoprenoid pathway gene and astaxanthin biosynthesis gene cluster produced 1,200 ${\mu}g$/g DCW of astaxanthin, resulting 3-fold increased production of astaxanthin.

• Journal of Korean Society for Quality Management
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• v.46 no.1
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• pp.11-26
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• 2018

Purpose: This study is to help the construction of smart factories of other manufacturing enterprises through IDIS 's case of smart factory construction. Methods: We introduce the four phases of implementing smart factory building by IDIS company, which produces a small quantity of multi-odd units. Results: Through the smart factory construction, the cost of product is reduced due to the improvement of total productivity such as office work, production work, and energy saving, and sales are enhanced by customized production, quality / delivery reliability improvement. Conclusion: We present the actual examples needed to build the manufacturer's smart factory.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.1
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• pp.1-9
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• 2000

In the present study, the IDI-type constant volume chamber, which utilizes the indirect injection stratified charge method, is used to solve several problems including misfires and cycle-variations caused by unstable initial ignitions. A subchamber has been used to make an ignitable mixture under the low mean equivalence ratio. After burned in the subchamber, the flame jet getting through the passage hode enters the main chamber and burns the lean charge. There are many factors which affect the combustion characteristics of the indirect injection stratified engine. The passage hole angle is the most important since it determines the direction of flame flows into the main chamber. In the present study, we measured the combustion pressure, and the wall temperature, and computed the heat flux through the cylinder wall in order to understand the combustion characteristics depending on passage hole angle and the equivalence ratio.

• Journal of Power System Engineering
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• v.1 no.1
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• pp.22-34
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• 1997

Circumstances require improving diesel engine, and many studies have been done in constant volume chamber(CVC). Because the combustion mechanism of a diesel engine has many difficulties with non-homogeneous nature, there has been a limitation to analyzing the combustion mechanism with CVC. Studies are often given in a real engine, but also it has difficulties in modifying configuration of combustion chamber etc. To get more easy way for mote engine-like test, a rapid compression mechanism has been introduced. This study addresses to designing a rapid compression expansion machine(RCEM) driven by compressed air, and to applying it on IDI diesel combustion chamber which has a glow plug. RCEM is introduced first and its characteristics are tested, then spray/combustion characteristics of diesel spray impinging on a glow plug in RCEM combustion chamber are investigated. The results show active combustion in the system employing spray impinging on a glow plug so as to improve combustion efficiency.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.3
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• pp.173-183
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• 2000

This study measured the zeta potential of both latex colloidal particles with carboxylate surface groups and glass beads (collectors) with silanol surface group employing various solution with different chemical characteristics. The results have been compared with the surface chemistry theory. The zeta potential of the particle and collector increased with increasing pH up to 5.0 regardless of the solution chemistry. For a monovalent electrolyte solution(sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (calcium chloride solution). In other words, the more the pH decreases, the larger the effect of neutral salts, such as NaCl and CaCl$_2$, have on the ζ-potential values. In this study, the PZPC(point of zero proton condition) of the particle and collector occurred below a pH of 3.1, H(sup)+ and OH(sup)- acted as a PDI (potential determining ion), and Na(sup)+ acted as an IDI(indifferent ion). The magnitude of the negative ζ-potential values of the particle and collector monotonically increased as the concentrations of Na(sup)+ or Ca(sup)2+([Na(sup)+] or [Ca(sup)2+]) decreased (the values of pNa or pCa increased). In the case of latex particles, the ζ-potential should aproach zero (isoelectric point; IEP) asymptotically as the pNa approaches zero, while in the case of calcium chloride electrolyte, ζ-potential reversal may be expected to occur around 3.16$\times$10(sup)-2MCaCl$_2$(pCa=1.5). pH, valance and ionic strength can be used in various ways to improve the water treatment efficiency by modifying the charge characteristics of the particle and collector. Predictive capability is far less certain when EDL(electrical double layer) repulsive forces exist between the particle and collector.

• The Korean Journal of Applied Statistics
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• v.22 no.1
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• pp.1-16
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• 2009

Recently, most companies are speeding up the movement of modeling and strategically applying IDI (Integration Database Information). This is due to the fact that CRM (Customer Relationship Management) representing communication and relation maintenance with customers, has been raised one of the most important issues for companies. From this point of view, this study is to develop the scoring campaign system connect-ing customer scoring model to marketing layer through data mining techniques which are the core factor for CRM. This developed system makes users easily choose the target customers as well as easily obtain customer scoring results under GUI circumstances which helps users easily apply as a result.

• Microbiology and Biotechnology Letters
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• v.46 no.2
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• pp.114-119
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• 2018

Astaxanthin is one of the major carotenoids used in pigment has a great economical value in pharmaceutical markets, feeding, nutraceutical and food industries. This study was to increase the production of astaxanthin by co-expression with transformed Escherichia coli using six genes involved in the non-mevalonate pathway. Involved in the non-mevalonate biosynthetic pathway of the strain Kocuria gwangalliensis were cloned dxs, ispC, ispD, ispE, ispF, ispG, ispH and idi genes in order to increase astaxanthin production from the transformed E. coli. And co-expression with the genes to compared the amount of astaxanthin production. This engineered E. coli, containing both the non-mevalonate pathway gene and the astaxanthin biosynthesis gene cluster, produced astaxanthin at $1,100{\mu}g/g$ DCW (dry cell weight), resulting in approximately three times the production of astaxanthin.

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.96-102
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• 2005

The tribocharge build-up in the slider disk interface can cause ESD (electrostatic discharge) damage. In turn, ESD can cause severe melting damage to MR or GMR heads. We investigated the tribovoltage/current build-up with smooth and textured disks in HDD, operating at increasing disk accelerations. We found that tribe-voltage/current were generated during pico-slider/disk interaction and those levels were about 0.1 ${\~}$ 0.3 V and 10 ${\~}$ 40 pA, respectively. Tribovoltage/current were abruptly increased and dissipated within the acceleration time in the case of textured disk but in the case of smooth disk tribovoltage was continuously increased until the end of uniform velocity region and the tribocurrent did not dissipate within the acceleration time. In the case of textured dist tribovoltage/current was reduced with increasing disk acceleration, but in the case of smooth disk it was increased.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.6
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• pp.13-20
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• 2005

The most typical fuel control devices of motorcycle engines have carburetors, they are simple in structure and reliable in work. Most of the motorcycle engines have used carburetors in the fuel system, but the fuel economy and the emissions of those engines are bad when we compared with automobile engines. According to stricter emission regulations and higher requirements for fuel economy, the application of the carburetor on the motorcycle engines would be limited. In this paper, we studied about the ECU of motorcycle engine controled by indirect method. A new engine system was designed and experiments were carried out. The experimental results for both carburetor type and ECU type were compared. Maximum torque of $1.053kg{\cdot}m$ at 6500rpm was measured. The engine torque controled using ECU was increased by $10\%$ compared with the carburetor type.

• Journal of the Society of Disaster Information
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• v.15 no.1
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• pp.143-152
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• 2019

Purpose : To analyze how the Fourth Industrial Revolution affects the gender gap. Method : This study regressed the relationship between ICT development index, network Readiness index and gender gap in 145 countries all over the world. Results : The ICT development index was not statistically significant, but the network readiness index was positively correlated with female labor participation rate and gender wage equality ratio, indicating that the progress of the $4^{th}$ industrial revolution increased female participation in labor but the wage gap has been shown to intensify. Conclusion : The results verify the hypothesis that the $4^{th}$ industrial revolution led by the information and communication revolution affects the labor market conditions of women.