• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.297-300
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• 2007

Due to its impressive compression performance, the H.264 video coder is highlighted in the video communications industry, such as DMB (Digital Multimedia Broadcasting), PMP (Portable Multimedia Player), etc. The main bottleneck to use the H.264 coder lays in the computational complexity, i.e. five times more complex than the market leading MPEG-4 Simple Profile codec. In this paper, we propose the hierarchical mode decision method for intraframe coding for the reduction of the computation complexity of the encoder. By determining the mode group early, the propose algorithm can skip the computationally demanding computation in the mode decision. The proposed algorithm is composed of three steps: $16{\times}16$ mode decision, $4{\times}4$ mode-group decisions, and final mode decision among the selected mode group. The simulation results show that the proposed algorithm achieves 20% to 50% reduction in the computational complexity compared with the conventional algorithm.

• ETRI Journal
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• v.29 no.6
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• pp.829-831
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• 2007

This letter proposes an analytical model to characterize medium utilization in IEEE 802.11e operating in HCCA-EDCA mixed mode (HEMM). In contrast to existing works which model the backoff process in individual stations, we consider the channel occupancy pattern. Additionally, our work considers the operation of HEMM, which is not widely documented. We show that the proposed model accurately characterizes medium utilization with no more than 5% error.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.46.2-46.2
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• 2011

Planck is already in active operation, and in a few years a detailed CMB anisotropy map will be compiled, surpassing WMAP both in temperature and polarization. The E mode - E mode autocorrelation power spectrum at large scales contains weak but sizable information on the history of cosmic reionization. We show our latest advance of our own simulation of cosmic reionization that incorporates Pop III stars, and provide a forecast for Planck polarization measurement.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.140-143
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• 1999

SSH(Sea Surface Height) from TOPEX/Poseidon and SST data are analyzed to estimate characteristics of annual and inter-annual variations in the East Asian seas(110E - l80E, 20N - 50N) from November 1992 to May 1998. In EOF analysis of SSH and SST, 57% and 97% of the variance are represented by the first two modes. The first mode of SSH and SST shows strong annual variations expected for steric changes. The second mode of SSH shows a long-term variation, but that of SST shows 3 - 4month offset from annual variation. In the EOF analysis of the SSH and SST, 61% and 54% of the total variance are represented by the first three modes. The first mode represented a long-term variation, and the third mode reflected the bi-ennial variation. The first three mode were not strongly correlated with ENSO. We further apply Canonical Correlation Analysis(CCA) to find the dominant correlation patterns with ENSO.

• Journal of the Daesoon Academy of Sciences
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• v.20
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• pp.95-123
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• 2009

This paper is designed to show the relationship between the Daesoon Principle and the recent theories like transpersonal psychology(TP) and predicate logic. According to TP there are 3 categories and 8 elements inside of not only human consciousness but civilization; three are pre-ego, ego, trans-ego, and eight are Uroboros, Typhon, Greater Mother, solarization, and repetition of the previous fours. The former is called, for Ken Wilber, the Average mode and the latter, the Advanced mode. I think that Daesoon thought including general Korean National religions belongs to the Advanced mode. I applied the predicate logic or paradoxical logic to understand of the Harmony of God and Man as well as Correspondence of Yin with Yang. The paradoxical logic has been not acceptable through two thousands years in the western tradition. I call the paradoxical logic the E type logic in this paper. The E type logic is most suitable logic for apprehending the Daesoon philosophy to a large extent. Finally my paper may contribute to the globalization of Daesoon mind system.

• International Journal of Costume and Fashion
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• v.5 no.2
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• pp.28-45
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• 2005

La $d{\acute{e}}marche$ et l'objet de cette recherche sont d'analyser, psychiquement, biologiquement, les marques de $l'intersexualit{\acute{e}}$ $pr{\acute{e}}sentent$ en Occident et les elements intersexuels, binaires dans le $v{\hat{e}}tement$, et ${\acute{e}}galement$ de comprendre $l'ambigu{\ddot{i}}t{\acute{e}}$ ou encore la fusion des $identit{\acute{e}}s$ $sexu{\acute{e}}es$. qui $pr{\acute{e}}sente$ symboliquement ${\grave{a}}$ travers le $v{\hat{e}}tement$, dans la $soci{\acute{e}}t{\acute{e}}$ moderne. $Malgr{\acute{e}}$ tous les points communs et $diff{\acute{e}}rents$, la base fondamentale dans les $th{\acute{e}}ories$ de I'Occident est que tout individu est psychiquement, biologiquement en quelque sorte un intersexuel qui s'ignore, avec des variations selon l'individu. En $d{\acute{e}}finitive$, les compositions doubles des ${\acute{e}}l{\acute{e}}ments$ dans le $v{\hat{e}}tement$ occidental montraient $embl{\acute{e}}matiquement$ nos $qualit{\acute{e}}s$ doubles, masculins et $f{\acute{e}}minins$, et les trois ${\acute{e}}l{\acute{e}}ments$ semblent primordiaux pour $l'{\acute{e}}lucidation$ de la $pr{\acute{e}}disposition$ du porteur : la couleur du tissu, sa texture et la forme du $v{\hat{e}}tement$. La mode d'aujourd'hui bascule entre masculin et $f{\acute{e}}minin$. Cette fusion de la mode semble le reflet d'une tendance intersexuelle et d'une fusion du genre.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.7
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• pp.6-11
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• 2012

A mobile station(MS) in an 802.16e network manages its limited energy using the sleep mode operation. An MS can power down its physical operation components during the unavailability interval of the sleep mode. To reduce energy consumption by increasing the unavailability interval, this paper proposes an enhanced power saving mechanism(ePSM) when both activated Type I and Type II power saving classes(PSCs) exist in an MS. A performance evaluation confirms that ePSM results in the improved performance in terms of the unavailability interval as well as the energy consumption than conventional schemes.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.1
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• pp.1-21
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• 2013

The release of IEEE 802.15.4e specification significantly develops IEEE 802.15.4. The most inspiring improvement is the enhancement for medium access control (MAC) sublayer. To study the performance of IEEE 802.15.4e MAC, in this paper we first present an overview of IEEE 802.15.4e and introduce three MAC mechanisms in IEEE 802.15.4e. And the major concern here is the Time Slotted Channel Hopping (TSCH) mode that provides deterministic access and increases network capacity. Then a detailed analytical Markov chain model for TSCH carrier sense multiple access with collision avoidance (CSMA-CA) is presented. Expressions which cover most of the crucial issues in performance analysis such as the packet loss rate, energy consumption, normalized throughput, and average access delay are presented. Finally the performance evaluation for the TSCH mode is given and we make a comprehensive comparison with unslotted CSMA-CA in non-beacon enabled mode of IEEE 802.15.4. It can validate IEEE 802.15.4e network can provide low energy consumption, deterministic access and increase network capacity.

• Korean Journal of Optics and Photonics
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• v.17 no.3
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• pp.268-272
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• 2006

We have demonstrated the selection and the amplification of the components of an optical frequency comb using femto-second laser injection-locking technique. We used a mode-locked Ti:sapphire laser as a master laser and a single-mode diode laser as a slave laser. After passing through the interference filter with the center wavelength 794.7 nm and the transmittance bandwidth 1.5 nm, the optical frequency comb by mode-locked femto-second laser was injected into the slave laser. The injection-locked slave laser had $3{\sim}4$ multi-mode with the mode spacing 100.5 MHz, whichcorrespond to the repetition rate of a mode-locked Ti:sapphire laser. The power of the modes selected by femto-second laser injection-locking technique was amplified to several thousands times

• Korean Journal of Optics and Photonics
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• v.19 no.5
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• pp.343-348
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• 2008

This study was carried out to commercialize FTTH by developing a burst mode optical receiver for E-PON. The optical receiver was manufactured by minimizing the capacitance of a photodiode to improve sensitivity for meeting 10, 20 km OLT Rx standard of E-PON at the transmission speed of 1.25 Gb/s. When bit-error ratio is $10^{-12}$ and PRBS is $2^5-1$, sensitivity is -26 dBm, loud/soft ratio is 23 dB. Both preamble time and guard time were set to 102.4 ns (128 bit). After comparing a photodiode whose capacitance is 0.53 pF with another photodiode whose capacitance has been minimized to 0.26 pF, we could see that sensitivity improved to 0.7 dBm and so did bandwidth to 190 MHz of burst mode for the optical receiver manufactured by the photodiode whose capacitance is 0.26 pF.