• Proceedings of the Korean Society of Applied Entomolohy Conference
• /
• 2003.10a
• /
• pp.108-108
• /
• 2003

• Proceedings of the Korean Society of Applied Entomolohy Conference
• /
• 2003.10a
• /
• pp.109-109
• /
• 2003

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.9 no.3
• /
• pp.184-190
• /
• 2004

The influences of impeller types on morphology and protein expression were investigated in a submerged culture of Aspergillus oryzae. The impeller types strongly affected mycelial morphology and protein production in batch and fed-batch fermentations. Cells that were cultured by propeller agitation grew in the form of a pellet, whereas cells that were cultured by turbine agitation grew in a freely dispersed-hyphal manner and in a clumped form. Pellet-grown cells showed high levels of protein production for both the intracellularly heterologous protein (${\beta}$-glucuronidase) and the extracellularly homologous protein (${\alpha}$-amylase). The feeding mode of the carbon source also influenced the morphological distribution and protein expression in fed-batch fermentation of A. oryzae. Pulsed-feeding mainly showed high protein expression and homogeneous distribution of pellet whereas continuous feeding resulted in less protein expression and heterogeneous distribution with pellet and dispersed-hyphae. The pellet growth with propeller agitation paralleling with the pulsed-feeding of carbon source showed a high level of protein production in the submerged fed-batch fermentation of recombinant A. oryzae.

• Computers and Concrete
• /
• v.7 no.2
• /
• pp.87-102
• /
• 2010

This paper discusses new capabilities developed for the Virtual Penetration Laboratory (VPL) software package to address the challenges of determining Penetration Resistance (PR) equations for concrete materials. Specifically, the paper introduces a three-invariant concrete constitutive model recently developed by the authors. The Advanced Fundamental Concrete (AFC) model was developed to provide a fast-running predictive model to simulate the behavior of concrete and other high-strength geologic materials. The Continuous Evolutionary Algorithms (CEA) automatic fitting algorithms used to fit the new model are discussed, and then examples are presented to demonstrate the effectiveness of the new AFC model. Finally, the AFC model in conjunction with the VPL software package is used to develop a PR equation for a concrete material.

• ETRI Journal
• /
• v.26 no.6
• /
• pp.661-664
• /
• 2004

The thermal behavior of an arrayed-waveguide grating made of a silica/polymer hybrid waveguide was examined. We experimentally confirmed that the hybrid waveguide is effective to decrease the temperature and polarization dependence of the center wavelength owing to the negative thermo-optic coefficient of the refractive index and extremely low baking temperature of the polymer cladding. However, the detachment of the polymer cladding from the silica core, which took place either during a repeated heat cycle test or during long-term storage in atmosphere, was a serious problem for practical use.

• ETRI Journal
• /
• v.27 no.5
• /
• pp.497-503
• /
• 2005

In this paper, we present a performance analysis for an MPEG-4 video codec based on the on-chip network communication architecture. The existing on-chip buses of system-on-a-chip (SoC) have some limitation on data traffic bandwidth since a large number of silicon IPs share the bus. An on-chip network is introduced to solve the problem of on-chip buses, in which the concept of a computer network is applied to the communication architecture of SoC. We compared the performance of the MPEG-4 video codec based on the on-chip network and Advanced Micro-controller Bus Architecture (AMBA) on-chip bus. Experimental results show that the performance of the MPEG-4 video codec based on the on-chip network is improved over 50% compared to the design based on a multi-layer AMBA bus.

• ETRI Journal
• /
• v.34 no.6
• /
• pp.970-973
• /
• 2012

In this letter, we report on the development progress of a pressure control organic vapor deposition (PCOVD) technology used to design and build a large area deposition system. We also investigate the growth characteristics of a pentacene thin film by PCOVD. Using the PCOVD method, the mobility and on/off current ratio of an organic thin-film transistor (OTFT) on a plastic substrate are $0.1cm^2/Vs$ and $10^6$, respectively. The developed OTFT can be applied to a flexible display on a plastic substrate.

• ETRI Journal
• /
• v.34 no.6
• /
• pp.946-949
• /
• 2012

We present the optimization of a birefringence-enhanced-waveguide (BWG)-based polarization beam splitter (PBS) in a Mach-Zehnder interferometer (MZI) configuration and analyze the structure-dependent or polarization-dependent phase difference, using a delay-line MZI (DL-MZI). We fabricate the DL-MZI using silica-based planar lightwave circuit technology and, using the DL-MZI, demonstrate the ability to optimize a PBS by measuring the birefringence of the BWG and structure-dependent phase offset.

• ETRI Journal
• /
• v.25 no.6
• /
• pp.535-537
• /
• 2003

We propose a rigorous 2D approximation technique for the 3D waveguide structures; it can minimize the well-known approximation errors of the commonly used effective index method. The main concept of the proposed technique is to compensate for the effective cladding index in the equivalent slab model of the original channel waveguide from the modal effective index calculated by the nonuniform 2D finite difference method. With simulations, we used the proposed technique to calculate the coupling characteristics of a directional coupler by the 2D beam propagation method, and the results were almost exactly the same as the results calculated by the 3D beam propagation method.

• ETRI Journal
• /
• v.27 no.3
• /
• pp.337-340
• /
• 2005

A spot-size converted Fabry-Perot laser diode (LD) was flip-chip bonded to a silica-terraced planar lightwave circuit(PLC) platform to examine the effect of the silica terrace on the heat dissipation of the LD module. From the measurement of the light-current characteristics, it was discovered that the silica terrace itself is not a strong thermal barrier, but the encapsulation of the integrated LD with an index-matching polymer resin more or less deteriorates the heat dissipation.