• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.76-76
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• 2003

Eleven wrasse species inhabit the coastal waters of Jeju Island, Korea. They are the target of leisure fishing and are considered good eating. We investigated the distribution of standard length (SL) by sex of wrasse in Jeju coastal waters for Halichores poecilopterus, H. tenuispinis, Pseudolabrus japonicus, and Pteragogus flagellifera. A cross-section of the ovary showed the ovarian cavity and ovarian lamellae containing oocytes. A cross-section of the testis showed many lobules containing spermatogonia and spermatocytes. A cross-section of a gonad undergoing sex reversal showed the regression or reduction of oocytes and some spermatocytes located in the ovarian lamellae. A cross-section of a sex-reversed testis showed the primary structure of the ovary, with spermatocytes distributed in the epithelium of the lamellae, and reformed seminiferous ducts in the basement lamellae. (중략)

• Journal of Veterinary Clinics
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• v.25 no.3
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• pp.221-223
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• 2008

SRY gene is normally responsible for testis induction, yet testis development can occur in the absence of SRY. In here, we analyzed the SRY-negative sex reversal in cocker spaniel, at 1.5 year-old. The attacked dog was suffered from enlarged clitoris, and resulted in disorder of urination. By surgically approach, enlarged clitoris and one testis, which are apparently seen, are removed. Additionally, thorough the abdomen surgery, uterus and ovary-like mass were removed. The dog had XX, chromosome, showed negative for SRY-gene, and the mass had the ovary-testis structure. In other words, based on the macroscopic, cytogenic, and histological study, we can diagnose the cocker spaniel as SRY-negative sex reversal.

• Journal of Magnetics
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• v.17 no.2
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• pp.124-128
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• 2012

Many different converter topologies have been developed with a view to use the minimum number of switches in order to reduce construction costs. Among this research, the four-switch converter topology with a novel PWM control technique based on the current controlled PWM method is thought to be a good solution. In this paper, a two dimensional time-stepped voltage source finite-element method (FEM) is used to analyze the characteristics of a Flux-Reversal Machine (FRM) with a 4-switch converter. To validate the proposed computational method, a digital signal processor (DSP) installed controller and prototype FRM are built and experiments performed.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.12
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• pp.700-708
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• 2004

Flux-reversal machine (FRM) is a new doubly-salient stator-permanent magnet (PM) machine with flux linkage reversal in the stator concentrated windings. It can operate in both motoring and generating modes. In this paper, a novel design technique to improve the performance of FRM is proposed. Proposed techniques have a new stator winding and a magnet arrangement method. The stator and rotor shape with a concave type and a flux barrier are also proposed. According to the experimental results, it is shown that the proposed FRM have an improved performance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.5
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• pp.403-407
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• 2010

This paper shows that the diffraction efficiency is influenced by superadditivity for the combination of the different developing agent and concentrations in the reversal bleach applied to the Slavich PFG-01 plate to be used for recording transmission holograms. The four developers based on ascorbic acid in combination with metol, phenidone, hydroquinone respectively, were studied. In diffraction efficiency aspect, the superadditivity effect of mixture of two developing agents is lower than one developing agent developer, AAC in the reversal bleach.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.1
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• pp.185-192
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• 1995

In this study, very fine photoresist pattern was examined using the image reversal process. And very fine photoriesist pattern (less than 0.2um) was obtsined by optimizing the exposure and reversal baking condition of photoresist. The produced pattern does not show the loss of thickness, and has a sparp negative edge profile. also, the ion implanted 0.25um T-shaped gate MESFET was fabricated using this resist pattern and the directional evaporation of gate metal. The fabricated MESFET has the maximum transconductance of 302 mS/mm, and the threshold voltage of -1.8V, and the drain saturation current of this MESFET was 191 mA/mm.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.471-476
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• 2001

The main object of this study is to develop a reliable FEM simulation technique for stability test using ABAQUS software and to clarify the effect of base profile of a steel D&I(drawn and ironed) can on the dome reversal pressure. For the can after body making simulation, two kind of stability test, dome buckle test and axial crush test are performed. The factors studied in the base profile on the dome reversal pressure are the base diameter, the rim radius, the dome shoulder radius, the dome radius and the dome depth. Within the limits before the occurrence of normal snap-through buckling of dome, the dome reversal pressure is improved by decreasing the base diameter, increasing the dome depth or increasing the dome shoulder depth.

• Journal of Mechanical Science and Technology
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• v.15 no.12
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• pp.1892-1899
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• 2001

An experimental study was performed for measuring velocity and turbulence intensity in a circular tube for Re= 10,000, 15,000 and 20,000, with swirl and without swirling flow. The velocity fields were measured using PIV techniques and swirl motion was produced by a tangential inlet condition. Some preliminary measurements indicated that over the first 4 diameter, two regions of flow reversal were set up (the so called 2-cell structure). At the highest Reynolds numbers, the maximum values of the measured axial velocity components had moved toward the test tube wall and produce more flow reversal at the conter of the tube. As the Reynolds number increased, the turbulence intensity of swilling flow at the tube inlet also increased.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.77-84
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• 2003

In this paper, the refined plastic-hinge analysis accounting for the effect of strain reversal caused by non-proportional loading is developed. This analysis accounts for material and geometric nonlinearities of the structural system and its component members. Moreover, the problem, conventional refined plastic-hinge analyses have underestimated the strength of structures subjected to non-proportional loading, is overcome. The modified stiffness degradation model approximating the effect of strain reversal is discussed in detail. The proposed analysis is verified by the comparison of the finite element analysis. A case study shows that the effect of strain reversal is a very crucial element to be considered in second-order plastic-hinge analysis. The proposed analysis is shown to be an efficient, reliable tool ready to be implemented into design practice.

• Journal of Magnetics
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• v.19 no.3
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• pp.237-240
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• 2014

For heat-assisted magnetic recording, magnetization reversal probabilities of nano-Pt/MnSb multilayer film with perpendicular magnetic anisotropy under thermal pulse activation were investigated numerically by solving the Landau-Lifshift Gilbert Equation. Magnetic parameters of nano-Pt/MnSb multilayer were used with anisotropy energy of $3{\times}10^5$ erg/cc and saturation magnetization of 2100 G, which offer more than 10 y data stability at room temperature. Scheme of driven magnetic field and thermal pulse on writing mechanism was designed closely to real experiment. This study found that the chosen material is potential to be used as a high density magnetic storage that requires low writing field less than two-hundreds Oersted through definite heating and cooling interval. The possibility of writing data with a zero driven magnetic field also became an important result. Further study is recommended on the thickness of media and thermal pulse design as the essential parameters of the reversal magnetization.