• Biotechnology and Bioprocess Engineering:BBE
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• v.4 no.1
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• pp.59-62
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• 1999

The recombinant bacteria strain DPD2540, containing a fabA::luxCDABE fusion, was used to detect the toxicity of various chemicals in this study. Membrane damaging agents such as phenol, ethanol, and cerulenin induced a rapid bioluminescent response from this strain. Other toxic agents, such as DNA-damaging or oxidative-damaging chemicals, showed a delayed bioluminescent response in which the maximum peak appeared over 150 min after induction. This strain was also tested for measurement of toxicity in field samples such as wastewater and river water effluents.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.518-524
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• 2014

The substrate doping concentration dependence of strain-enhanced electron mobility in (110)/<110> nMOSFETs is investigated by using a self-consistent Schr$\ddot{o}$dinger-Poisson solver. The electron mobility model includes Coulomb, phonon, and surface roughness scattering. The calculated results show that, in contrast to (100)/<110> case, the longitudinal tensile strain-induced electron mobility enhancement on the (110)/<110> can be increased at high substrate doping concentration.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.87.2-87
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• 2003

Long-term repeated culturing of biocontrol agents on a certain medium often results in reduced biocontrol efficacy and altered physiology. Effect of culturing media on biocontrol ability and physiological state of Burkholderia gladioli strain B543 was investigated. Over 20 times repeated cultivation of B. giadioli strain B543 on Kings B medium or nutrient agar medium showed improved biological control of cucumber damping-off caused by Pythium ultimum, while one time cultivation on KB or NA did not. The repeated cultivation also induced the physiological changes of the biocontrol agent such as antifungal activity and the production of protease and siderophore. Our result indicates that adaptation to proper culturing medium can alter biocontrol ability and must consider in optimizing the use of biocontrol agents.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.25-28
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• 2005

The optical fiber is known for the proper sensor which can accomplish the structural health monitoring, Fiber Bragg Grating sensors are being studied more than any other fiber optic sensors due to good multiplexing capabilities. But because the signal stability of FBG sensors can be influenced by the strain gradient, it needs to analyze signal of FBG sensors. Particularly acoording to strain gradient induced by structural geometry or cracks, the spectrum peak of the FBG sensor signal can be split easily. In this paper, the spectrum analysis of the FBG sensor signal was performed and the region of embedment of FBG sensors was determined in $H_2$ pressure vessel by numerical method.

• International Journal of Automotive Technology
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• v.6 no.3
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• pp.277-283
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• 2005

Formability simulation of automotive panels at early design phases can reduce product and tooling development time and cost. However, for the simulation to be effective in leading the design process, fast and reliable results should be achieved with limited design definition and minimum modeling effort. In this paper, nonlinear finite element analysis is used to develop an automated process for the formability simulation of automotive body panels at early design phases. Due to the limited design definition at early design phases, the automated simulation process is based on the plane strain analysis for selected number of typical sections along the panel. Therefore, an entire panel can be analyzed with few sections. The state of plane strain can be easily induced, during simulation through symmetry and applied boundary conditions that simplify the modeling process. To study the reliability and effectiveness of the developed simulation process, the analytical results are compared with measured results of production automotive body side panels. The comparison demonstrates that the developed simulation process is reliable and can be effective for analyzing sheet metal formability, in early vehicle development phases.

• Structural Engineering and Mechanics
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• v.38 no.1
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• pp.81-97
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• 2011

In this research, the wavelet transform is used to analyze time response of a cracked beam carrying moving mass for damage detection. In this respect, a new damage detection method based on the combined use of continuous and discrete wavelet transforms is proposed. It is shown that this method is more capable in making damage signature evident than the traditional two approaches based on direct investigation of the wavelet coefficients of structural response. By the proposed method, it is concluded that strain data outperforms displacement data at the same point in revealing damage signature. In addition, influence of moving mass-induced terms such as gravitational, Coriolis, centrifuge forces, and pure inertia force along the deflection direction to damage detection is investigated on a sample case. From this analysis it is concluded that centrifuge force has the most influence on making both displacement and strain data damage-sensitive. The Coriolis effect is the second to improve the damage-sensitivity of data. However, its impact is considerably less than the former. The rest, on the other hand, are observed to be insufficient alone.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.7
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• pp.1302-1308
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• 2002

Thermo-mechanical and flexural behavior of a wire-bond plastic ball grid array (WB-PBGA) package are characterized by high sensitive moire interferometry. Moire fringe patterns are recorded and analyzed for several bending loads and temperatures. At the temperature higher than $100^{\circ}C$, the inelastic deformation in solder balls become more dominant, so that the bending of the molding compound decreases while temperature increases. The deformation caused by thermally induced bending is compared with that caused by mechanical bending. The strain results show that the solder ball located at the edge of the chip has largest shear strain by the thermal load while the maximum average shear strain by the bending moment occurs in the end solder.

• Nuclear Engineering and Technology
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• v.32 no.4
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• pp.299-308
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• 2000

A safety assessment of reactor vessel lower head integrity under in-vessel vapor explosion loads has been performed. The core melt relocation parameters were chosen within the ranges of physically realizable bounds. The premixing and explosion calculations were performed using TRACER-II code. Using the calculated explosion pressures imposed on the lower head inner wall, strain calculations were peformed using ANSYS code. Then, the calculated strain results and the established failure criteria were used in determining the failure probability of the lower head, In the explosion analyses, it is shown that the explosion impulses are not altered significantly by the uncertain parameters of triggering location and time, fuel and vapor volume fractions in uniform premixture bounding calculations. Strain analyses show that the vapor explosion-induced lower head failure is not possible under the present framework of assessment. The result of static analysis using the conservative explosion-end pressure of 50 MPa also supports the conclusion. It is recommended, however, that an assessment of fracture mechanics for preexisting cracks be also considered to obtain a more concrete conclusion.

• Applied Microscopy
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• v.45 no.2
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• pp.44-51
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• 2015

At room temperature, metallic glasses deform inhomogeneously by strain localization into narrow bands as a result of yielding due to an external force. When shear bands are generated during deformation, often nanocrystals form at the shear bands. Experimental results on the deformation of bulk metallic glass in the current study suggest that the occurrence of nanocrystallization at a shear band implies the loading condition that induces deformation is more triaxial in nature than uniaxial. Under a compressive stress state, the geometrical constraint strain imposed by the stress triaxiality plays a crucial role in the deformation-induced nanocrystallization at the shear bands.

• Journal of Microbiology
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• v.34 no.3
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• pp.289-293
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• 1996

A cadimium-resistant strain isolated from Anyang stream, Azomonas agilis PY101 exhibited strong resistance to 1000 ppm of cadmium ion $(Cd^{2+})$. A agilis PY101 also exhibited resistance to various antibiotics, such as amoxicillin, amplicillin, bacitracin, cefazolin, erythromycin, penicillin, tetracycline, and vancomycin. In the presence of $Cd^{2+}$, the growth of A. agilis PY101 started after an extended lag phase and produced a green-fluorescent pigment induced by cadmium. The dramatic decrease (approximately 400ppm) of concentration of $cd^{2+}$ in the culture medium during the growth phase of A. agilis PY101 was confirmed by the inductively coupled plasma-atomic emission spectrophotometer. Transmission electron microscopic analysis revealed that A. agilis PY 101 actively accumulated $Cd^{2+}$ in the cytoplasm.