• 한국생산제조학회지
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• 제7권3호
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• pp.79-84
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• 1998

It is very difficult to analyze the transient temperature distribution during quenching of the steel because of coupled effects among temperature, structures and stresses. In this paper, using Inoue's equation of evolution and mixture rule, transient temperature distribution is calculated by the finite element method considering latent heat of transformation structure and temperature dependence of physical and mechanical prperties for the 0.45% carbon cylindrical steel bar with 40mm diameter and 20mm height during end-quenching.

• Molecules and Cells
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• 제39권9호
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• pp.705-713
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• 2016

The efficiency of Agrobacterium-mediated transformation in plants depends on the virulence of Agrobacterium strains, the plant tissue culture conditions, and the susceptibility of host plants. Understanding the molecular interactions between Agrobacterium and host plant cells is crucial when manipulating the susceptibility of recalcitrant crop plants and protecting orchard trees from crown gall disease. It was discovered that Arabidopsis voltage-dependent anion channel 1 (atvdac1) mutant has drastic effects on Agrobacterium-mediated tumorigenesis and growth developmental phenotypes, and that these effects are dependent on a Ws-0 genetic background. Genetic complementation of Arabidopsis vdac1 mutants and yeast porin1-deficient strain with members of the AtVDAC gene family revealed that AtVDAC1 is required for Agrobacterium-mediated transformation, and there is weak functional redundancy between AtVDAC1 and AtVDAC3, which is independent of porin activity. Furthermore, atvdac1 mutants were deficient in transient and stable transformation by Agrobacterium, suggesting that AtVDAC1 is involved in the early stages of Agrobacterium infection prior to transferred-DNA (T-DNA) integration. Transgenic plants overexpressing AtVDAC1 not only complemented the phenotypes of the atvdac1 mutant, but also showed high efficiency of transient T-DNA gene expression; however, the efficiency of stable transformation was not affected. Moreover, the effect of phytohormone treatment on competence to Agrobacterium was compromised in atvdac1 mutants. These data indicate that AtVDAC1 regulates the competence of Arabidopsis to Agrobacterium infection.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권2호
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• pp.288-293
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• 2017

Transient simulation capability with an implicit time derivation method is a missing feature in deterministic Boltzmann equation solvers. The H-transformation, which is critical for the stable simulation of nanoscale devices, introduces difficulties for the transient simulation. In this work, the transient simulation of graphene sheets is reported. It is shown that simulation of homogeneous systems can be done without abandoning the H-transformation, as much as a specially designed discretization method is employed. The AC mobility and step response of the graphene sheet on the $SiO_2$ substrate are simulated.

• Journal of Plant Biotechnology
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• 제31권3호
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• pp.185-190
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• 2004

Agrobacterium을 이용한 GUS 유전자를 효과적으로 발현시키기 위하여 수행되어진 실험 결과를 요약하면 다음과 같다. 박테이라 농도별 실험을 수행한 결과 균의 전처리 배양 농도 O $D_{600nm}$ 0.3일때 원심분리한 후 얻어진 균을 희석한 후의 최종 농도는 O $D_{600nm}$ 0.8로 맞춘 실험 처리구에서 GUS 유전자 발현율이55%로 가장 높게 나타났다. 병원성 유도 배지 내에 Acetosyringone (AS)이 첨가되지 않은 경우 GUS 유전자가 발현된 고추 잎을 얻을 수 없었으나, 200$\mu$M을 첨가했을 때 90%의 가장 높은 GUS 유전자 발현율을 나타내어 많은 수의 GUS spots을 관찰할 수 있었다. Agrobacterium에 의한 고추 잎의 감염 정도를 조사한 바 Agrobacterium으로 감염시킨지 3일째부터는 박테리아 에한 감염 정도가 심해져서 GUS 유전자 발현 정도가 약해지므로 Agrobacterium으로 감염시킨지 2일째 되었을 때 GUS 유전자 발현이 가장 강하게 나타난 것을 확인하였다. 이 같은 결과는 박테리아에 의한 감염이 일어난지 3일째 부터는 식물체의 감염부위 고사를 일으키는 것과 관련된 것으로 보인다.

• Journal of Plant Biotechnology
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• 제7권2호
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• pp.113-121
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• 2005

The objective of this study was to identify the major parameters controlling DNA delivery by particle bombardment to immature embryos of Chinese spring wheat (Triticum aestivum L.). Efficiency of DNA (uidA gene) delivery was assessed by transient GUS (${\beta}$-glucuronidase) expression in bombarded tissues. Of the parameters analyzed, acceleration pressure, bombardment distance, chamber vacuum pressure, bombardment times, osmotic conditioning of culture had a remarkable influence on transient gene expression. A bombardment procedure suitable for Chinese spring wheat cultivars was developed which allowed high-efficiency DNA delivery combined with reduced damage to target tissues. The high efficiency made the system practical for wheat genetic transformation research and accelerating wheat breeding programs.

• Journal of Plant Biotechnology
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• 제7권4호
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• pp.219-223
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• 2005

We investigated chemical-wounding effect on Agrobacterium-mediated Chinese cabbage transformation via vacuum infiltration. Pre-germinated or germinating Chinese cabbage seeds were infiltrated with Agrobacterium tumefaciens LBA4404 cells carrying either GUS gene (pBI121) or hepatitis B virus surface antigen DNA (pBIHBsAg). Prior to agroinfiltration process, the seeds were soaked in sodium hydrosulfite (SHS) solution or just in sterile water as a control. Comparative transformation efficiency was determined by both of histochemistry and ELISA. We could demonstrate that SHS solution treatment especially to 1-day or 2-days old germinating seeds efficiently improved transformation process, and therefore, transient expression level. This strongly indicated that Agrobacterium infection could be facilitated indeed by SHS-causing wounds on Chinese cabbage seeds.

• Journal of Power Electronics
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• 제9권3호
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• pp.507-515
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• 2009

This paper proposes an autonomous decentralized control for a parallel connected uninterruptible power supply (UPS) system based on a fast power detection method using a FPGA based hardware controller for a single phase system. Each UPS unit detects only its output voltage and current without communications signal exchange and a quasi dq transformation method is applied to detect the phase and amplitude of the output voltage and the output current for the single phase system. Fast power detection can be achieved based on a quasi dq transformation, which results in a realization of very fast transient response under rapid load change. In the proposed method, the entire control system is implemented in one FPGA chip. Complicated calculations are assigned to hardware calculation logic, and the parallel processing circuit makes it possible to realize minimized calculation time. Also, an Nios II CPU core is implemented in the same FPGA chip, and the software can be applied for non-time critical calculations. Applying this control system, an autonomous decentralized UPS system with very fast transient response is realized. Feasibility and stable operation are confirmed by means of an experimental setup with three UPSs connected in parallel. Also, rapid load change is applied and excellent performance of the system is confirmed in terms of transient response and stability.

• Journal of Applied Biological Chemistry
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• 제48권4호
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• pp.229-230
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• 2005

• KSBB Journal
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• 제21권6호
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• pp.489-492
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• 2006

분자육종의 목적을 위하여 Agrobacterium을 이용한 Brassica napus 식물의 유전적 형질전환은 폭 넓게 시행되어 왔다. B. napus cv. napus는 유지작물의 하나이면서 이 또한 Agrobacterium을 이용한 형질전환이 가능하다. 본 연구에서는 agroinfiltration방법을 이용시 유채유묘의 형질전환이 낯은 효율로 나타나고 있으며 이는 fluorometric GUS assay에 의하여 판단되었다. 대조적으로 유채유묘에 대하여 sodium hydrosulfite 용액을 agroinfiltration 과정 이전에 처리할 경우 형질전환율이 상당히 증가하는 것을 관찰할 수 있었다. RT-PCR에 의한 GUS유전자발현의 확인을 통하여 유채유도를 이용한 일시발현체계의 개발가능성을 제시하였다.

• Advances in materials Research
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• 제6권1호
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• pp.27-43
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• 2017

The transient thermo-mechanical behavior of a simply-supported beam made of a functionally graded material (FGM) under the effect of a moving heat source is investigated. The FGM consists of a ceramic part (on the top), which is the hot side of the beam as the heat source motion takes place along this side, and a metal part (in the bottom), which is considered the cold side. Grading is in the transverse direction, with the properties being temperature-dependent. The main steps of the thermo-elastic modeling included deriving the partial differential equations for the temperatures and deflections in time and space, transforming them into ordinary differential equations using Laplace transformation, and finally using the inverse Laplace transformation to find the solutions. The effects of different parameters on the thermo-mechanical behavior of the beam are investigated, such as the convection coefficient and the heat source intensity and speed. The results show that temperatures, and hence the deflections and stresses increase with less heat convection from the beam surface, higher heat source intensity and low speeds.