• Journal of Microbiology and Biotechnology
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• 제17권12호
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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.

• 디지털융복합연구
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• 제16권9호
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• pp.413-419
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• 2018

스마트폰은 현대사회에서 꼭 필요한 통신수단이 되었고 이미 인류의 일상생활에 융합되었다. 만약에 미니 헤드 마운트 표시 장치(HMD)를 활용하여 증강현실 기술로 통신 중인 양쪽 상대방의 용모, 표정, 동작 등의 요소가 통화 환경에 들어오면 사용하는 사람에게 직관적이고 특별한 느낌을 준다. 그리고 이 방식으로 시각의 한계성을 넘어설 수 있으므로 미래 시각예술 영역의 크게 발전을 촉진할 수 있어서 이런 기술적인 문제에 관한 연구의 의미가 있다. 본 논문은 효과적인 AR 영상통화 구현 방법에 대한 현재 사용되는 기술 중 몇 가지를 융복합하여 실현 가능한 두 가지 가설방안을 세우고 분석과 비교하여 두 가지 가설방안의 문제점을 발견한다. 그리고 문제점에 대한 해결 가능한 디자인 방안을 꺼낸다. 또 사례연구의 방식으로 실제 사례를 제출하여 두 가지 가설 방안은 미래에 실현 가능하다는 결론을 검증한다. 이러한 기술들은 우리의 일상에 더욱 재미요소와 편리함을 제공할 것이라 예상된다. AR 영상통화를 순조롭게 구현하는 것은 예견할 수 있고 나중에 무한한 발전 가능성이 있다.

• 복식
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• 제62권2호
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• pp.1-12
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• 2012

Cloths wrapped around the body have been the basis of the dress of people all over the world for centuries. This study is to research detailed modifiable fashion styling methods in history and to give ideas to people such as fashion professionals who are interested in fashion styling so that they can create modifiable fashion styling easily in fashion fields. The characteristics of modifiable fashion styling methods from ancient to middle ages are as follows. The first modifiable styling method is to expose the knots on the surface of the garments, and the knots were mainly located on the upper part of the body. The second method is a wrapping type of the modifiable styling method, which shows a lot of variant simple shapes of cloths. This method helped develop many wrapping methods over time. The third way is the fixed type of the modifiable styling method, and it uses accessories such as fibulae, belts to fix cloths, to create many different styles. The accessories are located on around either the neck or waist. The fourth method is the composite type of the modifiable styling methods mentioned above. This styling method is adapted in robe type clothes which makes the clothes look full of beautiful drapery. This study suggests that simple shapes of cloths can create enormous amount of styling which can be easily adapted and created nowadays.

• 한국융합학회논문지
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• 제9권7호
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• pp.185-191
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• 2018

프레임에서 픽셀로의 전환은 영화가 기술적 차원에서 거대한 전환을 이룬 것뿐만 아니라 영화언어 차원에서 근본적인 변화를 보여준다. 필름시대와 디지털 시대를 정의하며, 필름 시대의 영화와 디지털 시대의 영화가 스타일 차원에서 어떻게 구분되는가를 살펴보기 위해 본고는 지표성의 문제에 초점을 맞춘다. 지각적 사실주의 입장에서 보자면, 디지털 이미지에 대한 담론은 환영주의와 고전적 사실주의의 이분법적 구분을 해체한다. 이에 따라 이미지의 현실성은 지표적 차원에만 의존하지 않으며, 보다 근본적으로 관객이 어떻게 지각하느냐 하는 수용의 관점에서 고려되어야 한다는 결론이 도출된다. 디지털 시네마 시대에는 효과로서의 수용성이라는 차원에서 디지털 시네마의 지표성과 세계, 그리고 디지털 이미지 간의 관계에 대해 검토하는 작업을 해야 하며, 또한 이미지 생산의 관점에서 재고찰해야 할 것이다.

• Steel and Composite Structures
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• 제35권1호
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• pp.77-92
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• 2020

The present paper outlined a procedure for geometrically nonlinear dynamic analysis of functionally graded graphene platelets-reinforced (GPLR-FG) nanocomposite cylinder subjected to mechanical shock loading. The governing equation of motion for large deformation problems is derived using meshless local Petrov-Galerkin (MLPG) method based on total lagrangian approach. In the MLPG method, the radial point interpolation technique is employed to construct the shape functions. A micromechanical model based on the Halpin-Tsai model and rule of mixture is used for formulation the nonlinear functionally graded distribution of GPLs in polymer matrix of composites. Energy dissipation in analyses of the structure responding to dynamic loads is considered using the Rayleigh damping. The Newmark-Newton/Raphson method which is an incremental-iterative approach is implemented to solve the nonlinear dynamic equations. The results of the proposed method for homogenous material are compared with the finite element ones. A very good agreement is achieved between the MLPG and FEM with very fine meshing. In addition, the results have demonstrated that the MLPG method is more effective method compared with the FEM for very large deformation problems due to avoiding mesh distortion issues. Finally, the effect of GPLs distribution on strength, stiffness and dynamic characteristics of the cylinder are discussed in details. The obtained results show that the distribution of GPLs changed the mechanical properties, so a classification of different types and volume fraction exponent is established. Indeed by comparing the obtained results, the best compromise of nanocomposite cylinder is determined in terms of mechanical and dynamic properties for different load patterns. All these applications have shown that the present MLPG method is very effective for geometrically nonlinear analyses of GPLR-FG nanocomposite cylinder because of vanishing mesh distortion issue in large deformation problems. In addition, since in proposed method the distributed nodes are used for discretization the problem domain (rather than the meshing), modeling the functionally graded media yields to more accurate results.

• 한국재료학회지
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• 제26권11호
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• pp.611-622
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• 2016

Particle morphology change and different experimental condition analysis during composite fabrication process by traditional ball milling with discrete element method (DEM) simulation were investigated. A simulation of the three dimensional motion of balls in a traditional ball mill for research on the grinding mechanism was carried out by DEM simulation. We studied the motion of the balls, the ball behavior energy and velocity; the forces acting on the balls were calculated using traditional ball milling as simulated by DEM. The effect of the operational variables such as the rotational speed, ball material and size on the flow velocity, collision force and total impact energy were analyzed. The results showed that increased rotation speed with interaction impact energy between balls and balls, balls and pots and walls and balls. The rotation speed increases with an increase of the impact energy. Experiments were conducted to quantify the grinding performance under the same conditions. Furthermore, the results showed that ball motion affects the particle morphology, which changed from irregular type to plate type with increasing rotation speed. The evolution was also found to depend on the impact energy increase of the grinding media. These findings are useful to understand and optimize the particle motion and grinding behavior of traditional ball mills.

• The Journal of Asian Finance, Economics and Business
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• 제7권7호
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• pp.463-474
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• 2020

This study aims to investigate the impact of COVID-19 pandemic on the stock markets of sixteen countries. Pooled OLS regression, conventional t-test and Mann-Whitney test are used to estimate the results of the study. We construct a weekly panel data of COVID-19 new cases and stock returns. Pooled OLS estimation result shows that the growth rate of weekly new cases of COVID-19 negatively predicts the return in stock market. Next, the returns on leading stock indices of these countries during the COVID-19 outbreak period are compared with returns during the non-COVID period. We use a t-test and Mann-Whitney test to compare the returns. The results reveal that investors in these countries do not react to the media news of COVID-19 at the early stage of the pandemic. However, once the human-to-human transmissibility had been confirmed, all of the stock market indices negatively reacted to the news in the short- and long-event window. Interestingly, we noticed that the Shanghai Composite Index, which was severely affected during the short-event window, bounced back during the long-event window. This indicates that the Chinese government's drastic measures to contain the spread of the pandemic regained the confidence of investors in the Shanghai Stock Market.

• 자원환경지질
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• 제41권1호
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• pp.57-62
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• 2008

휴폐광지역의 산성광산배수를 처리하기 위한 자연정화처리시설로서 소택지의 설치가 증가하고 있다. 이러한 소택지의 기질물질로서는 흔히 석회석, 참나무조각, 버섯퇴비 등이 벌크형태로 적용된다. 이러한 소택지의 정화효율은 시간이 지남에 따라 점차 저하되며, 특히 산성배수와의 화학반응에 의한 기질물질 층의 투수계수 감소에 주로 기인한 것으로 파악된다. 본 연구의 목적은 산성광산배수 처리시설에서 황산염환원균(SRB) 고정화 담체의 적용성을 평가하기 위한 것이다. 고정화담체는 유기물질인 버섯퇴비와 참나무 퇴비, pH 완충제인 석회석가루 등을 토양미생물을 접종한 m-CSB와 혼합하여 제작하였다. 본 실험에서 고정화담체는 벌크형태에 비하여 pH, 황산염제거율 및 중금속 제거율에서 효율이 우수함을 확인할 수 있었다.

• Plant Biotechnology Reports
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• 제4권1호
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• pp.23-27
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• 2010

Quantitative trait loci (QTLs) controlling ability of somatic embryogenesis were identified in soybean. A frame map with 204-point markers was developed using an RI population consisting of 117 $F_{11}$ lines derived from a cross between cultivar 'Keburi' and a weedy soybean 'Masshokutou Kou 502'. The parents differed greatly in their abilities of somatic embryogenesis using immature cotyledons as explants. The ability of somatic embryogenesis was evaluated in five different experiments: the $F_{11}$ (evaluated in 1998) and $F_{15}$ (2002) generations cultured on basal media supplemented with $40\;mg\;l^{-1}$ 2,4-D (2,4-D1998 and 2,4-D2002), $F_{14}$ (2001) generation on medium with $40\;mg\;l^{-1}$ 2,4-D and high sucrose concentration [2,4-D2001 ($30\;g\;l^{-1}$ sucrose)], and the $F_{11}$ (1998) and $F_{12}$ (1999) generations on medium with $10\;mg\;l^{-1}$ NAA (NAA1998 and NAA1999). The RILs showed wide and continuous variations in each of the five experiments. In the composite interval mapping analysis, 2 QTLs were found in group 8 (D1b + W, LOD = 5.42, $r^2$ = 37.5) in the experiment of 2,4-D1998 and in group 6 (C2, LOD = 6.03, $r^2$ = 26.0) in the experiment of 2,4-D2001 (high concentration sucrose). In both QTLs, alleles of 'Masshokutou Kou 502' with high ability of somatic embryogenesis contributed to the QTLs. For the other three experiments, no QTL was detected in the criteria of LOD >3.0, suggesting the presence of minor genes.

• 한국약용작물학회지
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• 제26권5호
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• pp.417-429
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• 2018

Background: The objective of this study was to make colloidal dispersions of the active compounds of radix of Angelica gigas Nakai that could be charaterized as nano-composites using hot melt extrusion (HME). Food grade hydrophilic polymer matrices were used to disperse these compound in aqueous media. Methods and Results: Extrudate solid formulations (ESFs) mediated by various HPMCs (hydroxypropyl methylcelluloses) and Na-Alg polymers made from ultrafine powder of the radix of Angelica gigas Nakai were developed through a physical crosslink method (HME) using an ionization agent (treatment with acetic acid) and different food grade polymers [HPMCs, such as HP55, CN40H, AN6 and sodium alignate (Na-Alg)]. X-ray powder diffraction (XRD) analysis confirmed the amorphization of crystal compounds in the HP55-mediated extrudate solid formulation (HP55-ESF). Differential scanning calorimetry (DSC) analysis indicated a lower enthalpy (${\Delta}H=10.62J/g$) of glass transition temperature (Tg) in the HP55-ESF than in the other formulations. Infrared fourier transform spectroscopy (FT-IR) revealed that new functional groups were produced in the HP55-ESF. The content of phenolic compounds, flavonoid (including decursin and decursinol angelate) content, and antioxidant activity increased by 5, 10, and 2 times in the HP55-ESF, respectively. The production of water soluble (61.5%) nano-sized (323 nm) particles was achieved in the HP55-ESF. Conclusions: Nano-composites were developed herein utilizing melt-extruded solid dispersion technology, including food grade polymer enhanced nano dispersion (< 500 nm) of active compounds from the radix of Angelica gigas Nakai with enhanced solubility and bioavailability. These nano-composites of the radix of Angelica gigas Nakai can be developed and marketed as products with high therapeutic performance.