• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.6
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• pp.504-509
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• 2017

This paper proposes a procedure for designing a resonant network for induction cookers that enables the induction heating of magnetic and non-magnetic vessels. In order to design such network, the range of operating frequency must be determined according to the material of the vessels by measuring several parameters, such as equivalent resistance and inductance, which are reflected in the working coil of the vessels. Through this process, the capacitance of the resonant capacitor is determined. The PSIM simulation and experiment results verify the feasibility of the proposed design and the heating performance of the designed resonant network.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.8
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• pp.1418-1423
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• 2007

The topology of LLC half bridge resonant converter provides ZVS characteristic. The voltage stress and current stress are smaller than that of the general resonant converters. So the LLC HB resonant converter can be considered as a optimal circuit for the notebook computer adapter. In the adapter design, we should consider the weight, the size and the overheat of the adapter. Thus the higher efficiency is an essential particular. First of all, the optimal design of transformer is the most important facts. Some parameters should be considered in order to get the highest efficiency. The adapter is designed through the considering of these parameters including the PFC circuit as the pre-regulator. It converts AC line input into about DC 390V link voltage of the LLC HB converter input and the converter has 16V/90W ratings. The efficiency measured is about up to 93%.

• Korean Journal of Optics and Photonics
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• v.2 no.3
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• pp.127-132
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• 1991

We have obtained the analytic solutions of the four spherical mirror system free from the Seidel third order aberratios which are spherical aberration, coma, astigmatism, and distortion, Vignetting. Petzval field curvature, and optical properties according to the design parameters are numerically investigated and optimized. The numerical aperture of this system is 0.2 and the half field angle is $1.5^{\circ}$.

• Journal for History of Mathematics
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• v.15 no.2
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• pp.15-32
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• 2002

The first part of this thesis gives some brief explanation of the theory and history of imaginary elements in analytic geometry in the 19th century. The second part of this thesis discusses the theory of imaginary elements of synthetic geometry in the first half of the 19th century. Then the next part mentions the theory of imaginary elements of geometry in the second half of that same century. Particularly Christian von Staudt's and Felix Klein's theories are handled in this part. Von Staudt, who has completed the system of the synthetic projective geometry, used ‘involution’ in order to introduce a new concept ‘imaginary elements’- imaginary points, imaginary lines and imaginary plane-in synthetic geometry. Klein applied von Staudt's theory as he convey the result of the research in algebraic geometry in a picture. Von Staudt's and Klein's research may be regarded as the top of the effort to investigate possible relationship between real and imaginary structures.

• Earthquakes and Structures
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• v.3 no.3_4
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• pp.435-455
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• 2012

An impact on the ground surface may represent several phenomena, such as a crash of an airplane or an explosion or the passage of a train. In order to analyze and design structures and equipment to resist such a type of shocks, the response spectra for an impact on the ground must be given. We investigated the half-space motions due to impact using the finite element method. We performed extensive parametric analyses to define a suitable finite element model and arrive at displacement time histories and response spectra at varying distances from the impact point. The principal scope of our study has been to derive response spectra which: (a) provide insight and illustrate in detail the half-space response to an impact load, (b) can be readily used for the analysis of structures resting on a ground subjected to an impact and (c) are a new family of results for the impact problem and can serve as reference for future research.

• Journal of the Korea Society of Computer and Information
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• v.5 no.3
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• pp.64-69
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• 2000

This paper proposes a novel fractal coding method for fast encoding and high compression to shorten time to take on fractal encoding by using limited search area. First. the original image is contracted respectively by half and by quarter with the scaling method and bit-plane method. And then, the corresponding domain block of the quarter-sized image which is most similar with one range block of the half-sized image is searched within the limited area in order to reduce the encoding time extremely. As the result of the evaluation, the proposed algorithm provided much shorter encoding time and better compression ratio with a little degradation of the decoded image qualify than Jacquin's method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.9
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• pp.4541-4554
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• 2019

This paper proposes a planar projection DV-hop location algorithm (PTCDV-hop) based on the LED semi-angle at half power (SAHP, which accounts for LED SAHP characteristics in visible light communication (VLC)) and uses the DV-hop algorithm for range-free localization. Distances between source nodes and nodes positioned in three-dimensional indoor space are projected onto a two-dimensional plane to reduce complexity. Circles are structured by assigning source nodes (projected onto the horizontal plane of the assigned nodes) to be centers and the projection distances as radii. The proposed PTCDV-hop algorithm then determines the position of node location coordinates using the trilateral-weighted-centroid algorithm. Simulation results show localization errors of the proposed algorithm are on the order of magnitude of a millimeter when three sources are used. The PTCDV-hop algorithm has higher positioning accuracy and stronger dominance than the traditional DV-hop algorithm.

• Journal of Microbiology and Biotechnology
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• v.27 no.4
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• pp.718-724
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• 2017

The combination of rabies immunoglobulin (RIG) with a vaccine is currently effective against rabies infections, but improvements are needed. Genetic engineering antibody technology is an attractive approach for developing novel antibodies to replace RIG. In our previous study, a single-chain variable fragment, scFv57R, against rabies virus glycoprotein was constructed. However, its inherent weak stability and short half-life compared with the parent RIG may limit its diagnostic and therapeutic application. Therefore, an acidic tail of synuclein (ATS) derived from the C-terminal acidic tail of human alpha-synuclein protein was fused to the C-terminus of scFv57R in order to help it resist adverse stress and improve the stability and half-life. The tail showed no apparent effect on the preparation procedure and affinity of the protein, nor did it change the neutralizing potency in vitro. In the ELISA test of molecular stability, the ATS fusion form of the protein, scFv57R-ATS, showed an increase in thermal stability and longer half-life in serum than scFv57R. The protection against fatal rabies virus challenge improved after fusing the tail to the scFv, which may be attributed to the improved stability. Thus, the ATS fusion approach presented here is easily implemented and can be used as a new strategy to improve the stability and half-life of engineered antibody proteins for practical applications.

• Journal of Sericultural and Entomological Science
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• v.17 no.2
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• pp.97-100
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• 1975

This work was carried out to investigate the effects of several mode of picking leaves in autumn on development and harvest of branches, The results obtained are summarized ： (1) The effects of picking leaves in autumn were more conspicuous in weight of branches in length and/or size of branches. (2) In inverse propotion to the amount of picking leaves in autumn, the total weights of branches showed heavy in the non-picking leaves, the lower half part and the middle part-treatment, whereas are light in the upper half- and the all leaves picking-treatment, In spite of excessive picking leaves in autumn however, the middle part-treatment presented heavy weight of branches. (3) The yield of leaves in spring silkworm rearing, in propotion to the amount of picking leaves, were heavy in order of the non-picking leaves-, the middle part, and the lower half part-treatment, while both the upper half and the all leaves picking-treatment showed small amount of harvest. (4) The total yield of mulberry leaves and shoots of middle part-treatment, which showed the largest number of all was larger than that of the non-picking leaves and the all leave picking-treatment (leaving 5 leaves from upper part of shoot) at the ratio of 36％ and 13％, respectively.

• Journal of Environmental Science International
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• v.16 no.12
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• pp.1463-1468
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• 2007

Emission of methyl bromide(MeBr) of soil fumigant was implicated in stratospheric ozone depletion. To determine the environmental fate for 1,3-dichloropene(1,3-D) of alternatives fumigants for MeBr, this paper researched the transformation for 1,3-D in water and soil. Half lives of cis-1,3-D in water with first-order kinetics are 9.9day and 1.7day at $25^{\circ}C\;and\;40^{\circ}C$, half lives of trans-1,3-D are 8.6day and 1.5day at $25^{\circ}C\;and\;40^{\circ}C$, respectively. Transformation for 1,3-D in water at high temperature faster then at low temperature. Hydrolysis for 1,3-D in water are unaffected at $pH\;2.5{\sim}pH\;10.0$, but hydrolysis for 1,3-D at pH 11.5 higher then at $pH\;2.5{\sim}pH\;10.0$. Half lives of cis-1,3-D in soil are 11.5day and 7.7day at 3% and 10% of soil moisture, half lives of trans-1,3-D are 9.9day and 6.9day at 3% and 10% of soil moisture, respectively. Transformation for 1,3-D in water increased with increasing soil moisture. Transformation for trans-1,3-D isomer are more rapid then cis-1,3-D isomer in water and soil. This research has identified that transformation for 1,3-dichloropropene are affected by temperature, pH, soil moisture, and isomer of cis and trans in water and soil.