• Fisheries and Aquatic Sciences
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• v.5 no.4
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• pp.311-313
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• 2002

Proteolytic activity of live Uronema manum was analyzed by fluorescence polarization (FP) technique. Protease activity was measured by a decrease in FP value using fluorescein isothiocynate (FITC)-casein as a protein substrate. The results demonstrated an inverse linear relationship between fluorescence polarization (FP) values and live ciliate concentration over the range $1\times10^4\;to\;2\times10^5$ cells/well. However, the FP values of $10-10^3$ live parasites were not different significantly from that of control. Time-dependent decrease in FP value was shown in the wells containing live U. marinum. In the present study, FP assay had the benefit to provide measurements of substrate hydrolysis by live parasites in real-time, and did not require separations, precipitations, or transfers of reaction mixture.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.3
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• pp.47-52
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• 2012

This paper is in regard to design and experiment about the radar's circular polarization antenna operating in the Ku band. By using the Post to manufacture the circular polarization antenna using the linear antenna, it could reduce the structural size of an antenna. 3 Posts were used in order to broaden the Axial ration Bandwidth of the circular polarization antenna. The distance and length between Posts and Post were appropriately selected for the axial ratio optimization and applied in the design. It was verified that the designed antenna has the impedence bandwidth of 12.7%, axial ratio performance less than 2dB and gain of 7.8dBi.

• Korean Journal of Optics and Photonics
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• v.14 no.6
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• pp.657-662
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• 2003

Optimum Hamming apodized acousto-optic 2${\times}$2 add/drop multiplexers, using SiO$_2$ film loaded acoustic waveguide with angular offset to the Ti:LiNbO$_3$ waveguide, were fabricated. The four-port device consists of two input waveguides, a polarization beam splitter (PBS), two polarization conversion/acoustooptic tuning waveguide sections, a second PBS and two output waveguides. Insertion loss <7.1 ㏈ has been obtained and side-lobe of -19 ㏈ for -32 ㎽ RF driving power has been realized. Add/drop performance has been confirmed and a linear tuning rate of 8.1 nm/MHz and a 3 ㏈ spectral width of -1.5 nm were demonstrated.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.7
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• pp.769-777
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• 2010

In this paper, a switchable circularly polarized microstrip patch antenna using PIN diodes and corner slots on ground plane is proposed at 2.4 GHz. The proposed antenna has a square microstrip patch and ground plane that consists of two pair of slots and PIN diodes. The electrical lengths of the slots are adjusted by using the switching characteristic of the PIN diode, so the polarization of the proposed antenna can be switchable between linear, left-handed(LH) and right-handed(RH). By separating the ground plane for the DC bias, the size reduction effect is also obtained. When the proposed antenna is operated as linear polarization, the return loss and impedance bandwidth are 15 dB, 59 MHz, and when operated as LH and RH polarization, the minimum axial ratio and 3-dB axial ratio bandwidth are 1.17 dB, 1.67 dB, 28 MHz, and 32 MHz, respectively.

• Korean Journal of Optics and Photonics
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• v.9 no.3
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• pp.146-150
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• 1998

To enhance the resolution and the depth of focus of the patterns whose size reaches the optical resolution limits, the various imaging methods are being tried. Generally in the linear polarization illumination methods, the contrast gap exists between TE mode TM mode according to the pattern direction. However, through the previous research, the elliptical polarization illumination(EPI) method was proposed to overcome this contrast gap. In this research, we investigated the optimal polarization condition to be able to enhance the depth of focus(DOF) for the optional mask which is containing the opposite direction patterns by applying the various polarization conditions including EPI. The DOF according to each polarization condition was obtained by ED-Tree(Exposure-Defocus Tree) for the given exposure dose and CD error boundaries. As the result, we can ascertain th effect of EPI for the enhancement of DOF in some condition of optical system.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.8
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• pp.1289-1293
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• 1990

In this paper, the oscillation condition for the linear phase-conjugate oscillator which consists of one photorefractive crystal, two conventional mirrors, and two pump waves applied externally has been analyzed. In the result, it has been shown that the oscillation condition of this oscillator can be easily controlled by adjusting the various parameters such as the intensity ratio, polarization states, and light path difference of two pump waves, etc.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1366-1368
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• 2001

In this study it can be confirmed that the formula by the free-rotational dipole theory is similiar with that by the phenomenological theory and the non-linear permittivity is determined only with the third harmonic conponent of polarization. Various parameters of VDCN copolymers were obtained from fitting results with the related formula.

• Journal of the Optical Society of Korea
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• v.8 no.3
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• pp.122-126
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• 2004

The method to obtain four speckle patterns with relative phase shift of ${\pi}/2$ by passive devices such as two waveplates and a linear polarizer, awl to calculate the phase at each point of the speckle pattern in shearography with a Wollaston prism is presented, and the feasibility of the proposed method is theoretically demonstrated by Jones vector.

• Analytical Science and Technology
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• v.5 no.1
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• pp.97-101
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• 1992

Potentiodynamic corrosion tests were conducted to know the corrosion characteristics of the NiTi intermetallic compound composed of pure Ni and Ti in artificial saline. Tafel extrapolation and linear polarization technique show similar results. Corrosion current Icorr and corrosion rate was increased in the order of NiTi

• ETRI Journal
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• v.31 no.3
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• pp.271-281
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• 2009

This paper presents a novel multiband microstrip-fed right angle slot antenna design technique for multiple independent frequency bands. The new technique uses various slot sizes at various appropriate positions. We first propose a tri-band slot antenna consisting of three right angle slots. Then, a quad-band slot antenna is developed with four right angle slots which achieves slant ${\pm}45^{\circ}$ linear polarization, omnidirectional pattern coverage, good antenna gain, and acceptable impedance bandwidths over all the operating frequency range. Moreover, an open-circuited tuning stub is introduced to achieve good impedance matching. Both proposed antennas are designed on a ground plane of RT/duroid 5880 substrate with a thickness of 1.575 mm. The real measurable results show that the desired frequencies used in wireless communication systems, namely, WLAN and WiMax, are efficiently achieved.