• Steel and Composite Structures
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• 제32권5호
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• pp.687-699
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• 2019

In this paper, free and force vibration behaviors of graphene-reinforced composite functionally graded (GRC-FG) cylindrical shells in thermal environments are investigated based on Reddy's third-order shear deformation theory (HSDT). The GRC-FG cylindrical shells are composed of piece-wise pattern graphene-reinforced layers which have different volume fraction. Based on the extended Halpin-Tsai micromechanical model, the effective material properties of the resulting nanocomposites are evaluated. Using the Hamilton's principle and the assumed mode method, the motion equation of the GRC-FG cylindrical shells is formulated. Using the time- and frequency-domain methods, free and force vibration properties of the GRC-FG cylindrical shell are analyzed. Numerical cases are provided to study the effects of distribution of graphene, shell radius-to-thickness ratio and temperature changes on the free and force vibration responses of GRC-FG cylindrical shells.

• Food Science and Biotechnology
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• 제16권6호
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• pp.999-1005
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• 2007

An oil-in-water (O/W) emulsion [20 wt% com oil, 0.5-6.0 wt% fish gelatin (FG), pH 3.0] was produced by high pressure homogenization, and the influence of pH, protein concentration, and homogenization condition on the formation of FG-stabilized emulsions was assessed by measuring particle size distribution, electrical charge, creaming stability, microstructure, and free FG concentration in the emulsions. Optical microscopy indicated that there were some large droplets ($d>10\;{\mu}m$) in all FG-emulsions, nevertheless, the amount of large droplets tended to decrease with increasing FG concentration. More than 90% of FG was present free in the continuous phase of the emulsions. To facilitate droplet disruption and prevent droplet coalescence within the homogenizer, homogenization time was adjusted in O/W emulsions stabilized by 2.0 or 4.0 wt% FG. However, the increase in the number of pass rather promoted droplet coalescence. This study has shown that the FG may have some limited use as a protein emulsifier in O/W emulsions.

• 대한의용생체공학회:의공학회지
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• 제16권3호
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• pp.367-375
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• 1995

광범위 항생물질인 Ampicillin sodium(AMP-Na)을 두가지 방법 즉, 단순섞임과 bovine serum albumin(BSA)으로 microsphere화한 후 loading 하는 방법으로 fibrin glue(FG)를 제조하였고 이 FG로부터 AMP-Na의 서방성 시험을 시도하였다. 단순섞임의 경우 fibrinogen(FBNG)의 농도를 조적함으로서 FG로부터 AMP-Na의 지속적 방출을 달성할 수 있었으며 특히 이 microsphere를 glutaraldehyde로 가교화시킴으로서 용출속도를 더욱 늦출 수 있었다.(tO.9 : 33hr). FG의 rat perironeum에 대한 접착력은 FBNG과 thrombin의 농도가 각각 5.0%, 25~50 NIHU/ml에서 최대로 나타났다. Factor XIII의 농도는 0~500 U/1g of FBNG의 범위내에서 접착력에 거의 영향을 미치지 않았으며 incubation time은 60분일 때 최대로 나타났다. FG에 AMP-Na 및 BSA micorsphere를 loading하여도 접착력에는 큰 영향을 미치지 않았다.

• Advances in nano research
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• 제5권4호
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• pp.281-301
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• 2017

In this disquisition, an exact solution method is developed for analyzing the vibration characteristics of magneto-electro-elastic functionally graded (MEE-FG) beams by considering porosity distribution and various boundary conditions via a four-variable shear deformation refined beam theory for the first time. Magneto-electroelastic properties of porous FG beam are supposed to vary through the thickness direction and are modeled via modified power-law rule which is formulated using the concept of even and uneven porosity distributions. Porosities possibly occurring inside functionally graded materials (FGMs) during fabrication because of technical problem that lead to creation micro-voids in FG materials. So, it is necessary to consider the effect of porosities on the vibration behavior of MEE-FG beam in the present study. The governing differential equations and related boundary conditions of porous MEE-FG beam subjected to physical field are derived by Hamilton's principle based on a four-variable tangential-exponential refined theory which avoids the use of shear correction factor. An analytical solution procedure is used to achieve the natural frequencies of porous-FG beam supposed to magneto-electrical field which satisfies various boundary conditions. A parametric study is led to carry out the effects of material graduation exponent, porosity parameter, external magnetic potential, external electric voltage, slenderness ratio and various boundary conditions on dimensionless frequencies of porous MEE-FG beam. It is concluded that these parameters play noticeable roles on the vibration behavior of MEE-FG beam with porosities. Presented numerical results can be applied as benchmarks for future design of MEE-FG structures with porosity phases.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 춘계학술논문 발표대회
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• pp.47-50
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• 2007

This study investigates the properties of light weight foamed concrete (LWC) designed with various content of fine grains (FG). Test showed that LWC containing diverse powder materials with addition, more than 15% of FG, tended to decrease the fluidity of fresh concrete. 10% of FG content in LWC exhibited 4mm in sinking depth, which is the lowest value. This value dramatically increased at more than 15% of addition. However the concrete incorporating LSP proportionally increased the sinking depth in overall. As for the strength, the values of all specimens were under standardization of KS, except for the concrete adding 5 and 10% of FG. Apparent density of LWC showed the lowest value when used 10% of FG which was satisfied the 0.5 grade in KS. For the thermal conductivity, it was also indicated at 0.5 grade in KS, which is under $0.160W/(m{\cdot}k)$. In conclusion, it is demonstrated that adding 10% of FG in LWC was effective in the aspects of recycling of materials, cost effectiveness and quality.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2000년도 종합학술발표회 논문집 Vol.10 No.1
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• pp.193-196
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• 2000

본 논문에서는 FG-CPW(Finite-Ground Coplanar Wave-Guide) 구조의 단일 평형 다이오드 믹서에 대해서 논의된다. 주파수 영역은 무선 LAN 대역으로 선택하였다. RF 신호는 5.725-5.875 GHz, LO 신호는 5.58GHz, 그리고 IF 신호는 140 MHz가 사용된다. 제시된 FG-CPW 구조의 LPF(low pass filter)는 회의크기를 줄일 수 있으며, 불필요한 하모닉 억제 특성이 우수하다. 5.635 GHz에서 5 dBm의 Power를 갖는 LO신호가 입력될 때 6.2 dB 의 혼합기의 변환손실을 얻는다. 또한 LO-RF isolation과 LO-IF isolation은 각각 30 dB $\Omega$dB 의 특성을 보인다. 이 혼합기는 CPW 구조가 일반적으로 알려진 밀리미터 대역에서의 장점뿐만 아니라 C-Band의 무선 LAN 분야에도 충분히 응용될 수 있으리라 기대된다.

• The Plant Pathology Journal
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• 제35권5호
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• pp.393-405
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• 2019

Survival factor 1 (Svf1) is a protein involved in cell survival pathways. In Saccharomyces cerevisiae, Svf1 is required for the diauxic growth shift and survival under stress conditions. In this study, we characterized the role of FgSvf1, the Svf1 homolog in the homothallic ascomycete fungus Fusarium graminearum. In the FgSvf1 deletion mutant, conidial germination was delayed, vegetative growth was reduced, and pathogenicity was completely abolished. Although the FgSvf1 deletion mutant produced perithecia, the normal maturation of ascospore was dismissed in deletion mutant. The FgSvf1 deletion mutant also showed reduced resistance to osmotic, fungicide, and cold stress and reduced sensitivity to oxidative stress when compared to the wild-type strain. In addition, we showed that FgSvf1 affects glycolysis, which results in the abnormal vegetative growth in the FgSvf1 deletion mutant. Further, intracellular reactive oxygen species (ROS) accumulated in the FgSvf1 deletion mutant, and this accumulated ROS might be related to the reduced sensitivity to oxidative stress and the reduced resistance to cold stress and fungicide stress. Overall, understanding the role of FgSvf1 in F. graminearum provides a new target to control F. graminearum infections in fields.

• 한국식품영양과학회지
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• 제30권3호
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• pp.395-402
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• 2001

Bacillus subtilis 돌연변이주 중 ${\gamma}-GTP$활성이 높은 SM-2와 SM-10을 융합시켜 획득한 융합주 중 ${\gamma}-GTP$활성이 높은 융합주 FG-21의 배양적 특성을 조사하였다. 융합주 FG-21에 의한 ${\gamma}-GTP$의 생산은 1% glycerol, 1% peptone, 0.1% citric acid, 5 mM $K_2HPO_4$, 1 mM $FeCl_3$, 1 mM $MgCl_2$, 1 mM $NH_4Cl$, pH 7.0의 배지에 의해 $37^{\circ}C$에서 36시간 배양했을 때 621 U/mL으로 최대한 활성을 보였다. 융합주 FG-21이 생산한 biopolymer A가 단백질함량이 38.4%이고 B. subtilis K-1이 생산하는 biopolymer B의 단백질함량은 19.3%로 융합주 FG-21이 생산하는 Biopolymer A보다 함량이 낮았다. 융합주 FG-21의 biopolymer가 모균주의 biopolymer B보다 단백질함량이 높은 것은 상대적으로 높은 ${\gamma}-GTP$활성이 높아서 생성된 PGA가 levan보다 함량이 많기 때문인 것으로 사료된다. 총당함량은 biopolymer A가 58.5%, biopolymer B가 76.5%로 나타났다. 융합주 FG-21과 모균주가 생산하는 biopolymer의 단백질함량과 총당함량비는 융합주 FG-21이 생성한 biopolymer는 38 : 59. 모균주가 생산한 biopolymer B는 19 : 78의 비율이었고 HPLC 분석에 의한 biopolymer A와 B의 fructose함량은 각각 537.7 mg/g biopolymer, 764.4 mg/g biopolymer으로 나타났다. Biopolymer A와 B의 glutamic acid함량은 각각 163.7 mg/g, 94.3 mg/g이었다. Biopolymer A와 B의 fructose와 glutamic acid의 함량비는 각각 78 : 22, 89 : 11의 비로 함유되어 있었다. 따라서 융합주에 의해 생산된 biopolymer는 모균주보다 구성상태가 변화된 biopolymer를 생산한 것으로 판단되어 fusion과 같은 균주개량을 통하여 물질의 구성적, 물질적 변화된 biopolymer를 생산할 수 있을 것이라 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권6호
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• pp.843-847
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• 2004

In order to understand the effects of different oils on the production performances and polyunsaturated fatty acids and cholesterol level in the yolk. 160 Hexices hens at 42 wks were divided into four groups randomly. Each group fed with control diet (CG), control diet+5% fish oil (FG), control diet+5% palm oil (PG) and control diet+5% soybean oil (SG), respectively. After three weeks' experiment, the results showed that: different oils showed no significant effect on feed/egg weight, egg white weight, body weight, C16, C18:3 n-6 and C20:4 n-6 contents in the yolk (p>0.05). But the egg mass of PG was higher than SG (p<0.05), the average egg weight of CG was lower than FG (p<0.05), and the of PG was lower than FG (p<0.05), during the experiment, FG gained more than SG (p<0.05), the cholesterol level in yolk of FG was lower than PG and CG (p<0.01), meanwhile the C20:5 n-3 content of FG was higher than CG and SG (p<0.01), and no C20:5 n-3 was detected in PF, as far as C22:6 n-3 in the yolk was concerned, FG was higher than PG (p<0.01), the C18:1 n-9 content of SG was lower than PG (p<0.05), the C18:2 n-6 content of SG was the highest than other three groups (p<0.01), and CG was the lowest, showed significant to FG (p<0.05), the C18:3 n-3 content of FG was higher than SG and PG (p<0.05), and the C20:1 n-9 content of FG was higher than other groups (p<0.01). The results demonstrated that fish oil could decrease the cholesterol and increase the n-3 fatty acids content in the yolk, and increase the n-3/n-6 level.

• Structural Engineering and Mechanics
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• 제49권5호
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• pp.569-595
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• 2014

In this paper, a novel semi-energy finite strip method (FSM) is developed based on the concept of first order shear deformation theory (FSDT) in order to attempt the post-buckling solution for thin and relatively thick functionally graded (FG) plates under uniform end-shortening. In order to study the effects of through-the-thickness shear stresses on the post-buckling behavior of FG plates, two previously developed finite strip methods, i.e., semi-energy FSM based on the concept of classical laminated plate theory (CLPT) and a CLPT full-energy FSM, are also implemented. Moreover, the effects of aspect ratio on initial post-buckling stiffness of FG rectangular plates are studied. It has been shown that the variation of the ratio of initial post-buckling stiffness to pre-buckling stiffness ($S^*/S$) with respect to aspects ratios is quite independent of volume fractions of constituents in thin FG plates. It has also been seen that the universal curve representing the variation of ($S^*/S$) with aspect ratio of a FG plate demonstrate a saw shape curve. Moreover, it is revealed that for the thin FG plates in contrast to relatively thick plates, the variations of non-dimensional load versus end-shortening is independent of ceramic-metal volume fraction index. This means that the post-buckling behavior of thin FG plates and the thin pure isotropic plates is similar. The results are discussed in detail and compared with those obtained from finite element method (FEM) of analysis. The study of the results may have a great influence in design of FG plates encountering post-buckling behavior.