• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.3
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• pp.289-295
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• 1998

The purpose of this paper is to propose an improvement method of BER for coded 16-QAM under Rayleigh fading channel. To overcome the BER degradation due to the fading under mobile communication, we apply delay modulation technique which is efficient to get both a coding gain and approximately one-half those needed by Manchester coding on bandwidth requirements. Especially, the delay modulation scheme is insensitive to the $180^{\circ}$phase ambiquity common to NRZ-L and Manchester coding schemes. From the computer simulation, BER performance of our scheme has achieved about 3.8 dB improvement of about $10^{-4}$, compared to Manchester coded 16-QAM.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.67.1-67.1
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• 2003

Three new guaianolide type of sesquiterpene lactones, 8${\alpha}$-angeloyloxy-1${\alpha}$-hydroxy-3${\alpha}$,4${\alpha}$-epoxy-5${\alpha}$, 7${\alpha}$H-10(14), 11(13)-guaiadien-12,6${\alpha}$-olide (1), 8${\alpha}$-methylbutyryloxy-1${\alpha}$-hydroxy-3${\alpha}$, 4${\alpha}$-epoxy-5${\alpha}$, 7${\alpha}$H-10(14),11(13)-guaiadien-12,6${\alpha}$-olide (2), and 8${\alpha}$-isovaleryloxy-1${\alpha}$-hydroxy-3${\alpha}$, 4${\alpha}$-epoxy-5${\alpha}$, 7${\alpha}$H-10(14),11 (13)- guaiadien-12,6${\alpha}$-olide (3), together with six known sesquiterpenes, artemisolide (4), 3-methoxytanapartholide (5), deacetyllaurenobiolide (6), moxartenolide (7), arteminolide B (8), and arteminolide D (9) were isolated by bioassay-guided fractionation using the NF-kB mediated reporter gene assay system. (omitted)

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.6
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• pp.1-8
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• 1994

In this paper, in order to apply the idea MDPSK to TCM, we use signal set expansion and set partition by phase differences. Through this we propose the trellis-coded MDPSK. And the Viterbi decoder containing branch metrics of the squared Euclidean distance of the Lth order phase difference as well as the first order phase difference is introduced in order to improve the bit error rate(BER) in the differential detection of the trellis-coded MDPSK. The proposed Viterbi decoder is conceptually same to the sliding multiple symbol dection method which uses the branch metric with the first and Lth order phase differences. We investigate the performance of the uncoded DQPSK and the trallis-coded D8PSK in additive white Gaussian noise (AWGN) through the Monte Carlo simulation under the two cases of using and not using the Lth order phase difference metric. The study shows that trellis-coded 8DPSK is an attractive scheme for power and bandlimited systems while also improving the BER performance when the Viterbi decoder is employed to the Lth order phase order difference metric. This performance improvement has been obtained without sacrificing the bandwidth or the power efficiency.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.150-151
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• 2003

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the progressive deterioration of cognition and memory in association with widespread neuronal loss. AD is supposed to be very often associated with missense mutation located on homologous protein Presenilin (PS1) and (PS2). Up to now, the molecular mechanisms underlying the role of the gene mutation in AD still remain unclear. (omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.310.2-311
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• 2003

The effects of differences in the rate and composition of intravenous fluid replacement for urine loss on the pharmacokinetics and pharmacodynamics of torasemide were evaluated using rabbits as the animal model. Each rabbit received 2-h constant intravenous infusion of 1 mg/kg ∼ 1 of torasemide with 0％ replacement (treatment I, n = 6), 50％ replacement (treatment II, n = 9), and 100％ replacement with lactated Ringer's solution (treatment III, n = 8) as well as with 100％ replacement with 5％ dextrose in water(D-5-W, treatment IV, n=6). (omitted)

• ETRI Journal
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• v.37 no.5
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• pp.940-944
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• 2015

We present a frame synchronization algorithm for lowdensity parity-check (LDPC) coded burst transmissions, which combines a conventional pilots-assisted frame synchronization algorithm and a code-aided algorithm based on the mean magnitude of the soft outputs from the LDPC decoder. With moderate computational complexity, the proposed algorithm is more efficient in bandwidth than conventional pilots-assisted algorithms. When compared with other code-aided algorithms, the proposed algorithm offers a better trade-off between complexity and performance. Simulation results in the case of an 8-PSK system with (1944, 972) LDPC code show that the proposed algorithm can achieve a performance equivalent to that of the perfect frame synchronization, with a bandwidth efficiency loss of 0.06 dB due to the use of pilot symbols.

• The Journal of the Acoustical Society of Korea
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• v.17 no.8
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• pp.103-109
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• 1998

디지털신호의 변조에는 기본적으로 진폭 편이 변조(ASK: Amplitude-Shift Keying), 주파수 편이 변조(FSK: Frequency-Shift Keying), 위상 편이 변조(PSK: Phase-Shift Keying) 등의 세 가지 방법이 있다. 본 논문에서는 표본클록 합성계수 방식에 관한 이론을 고찰하고, 클록초기치 누적방식의 DDFS를 이용하여 위에서 언급한 변조방법을 실현할 수 있는 주파수 도약 대역 확산 통신에 적합한 변조기를 구현하였다. 또한, 합성된 출력주파수 의 정현파형에 대한 스펙트럼 분석과 PN(Pseudo Noise) 부호를 사용한 순시적인 주파수 도 약 상태, 위상제어의 가능성 등을 확인한 결과 실험으로부터 다음과 같은 결과를 얻었다. 첫 째, 합성된 출력주파수는 주파수 Index에 따라 기준주파수에 정확히 정수배가 되며, 둘째, 합성된 정현파형의 스펙트럼으로 기본파와 여러 고조파의 크기를 비교하여 본 결과 50[dB] 이상의 차이가 남으로서 고조파 성분들이 상당히 감소되었음을 확인하였고, 셋째, PN 코드 를 사용하여 순시적인 주파수 도약 상태를 확인하여 본 결과 스위칭 시간이 빠르기 때문에 주파수 도약 특성이 뛰어남을 알 수 있었으며 또한, 누산기의 set/reset 상태를 변화시킴에 따라 위상이 제어됨을 입증하였다.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.323.1-323.1
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• 2002

Apicidin ［cyclo(N-O-methyl-l -tryptophanyl-L -isoleucinyl-D-pipecolinyl-L-2-amino-8-oxodecano y)］. a histone deacetylase inhibitor. has been shown to cause growth arrest and morphological change of cancer cells. resulting from the alternation of protein expression. such as p21WAF1/Cip1 and gelsolin. However. proteome of altered by apicidin are poorly studied. In this study. we used a functional proteornics approach to identify the proteome altered by apicidin in Hela cells at 24hr post-treatment. (omitted)

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.4
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• pp.37-46
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• 1996

In this paper, we analyzed the performance improvement of the DS-CDMA/dPSK cellular mobile communication system with CCI canceller and RAKE receiver techniques in mobile radio channel which is characterized by AWGN, Multi-user interference (mUI) and frequency-selective rayleigh fading. System capacity i.e., number of user per cell has been derived and the evaluated results are shown in figuraes as a function of PN code sequence length, number of RAKE receiver tap, BER and E$_{b}$/N$_{o}$. The voice activity factor is assumed to be 3/8 the number of sectors in a cell 3 and MUI is modeled as gaussian process. From the results, the capacity of the DS-CDMA/DPSK cellular mobile communication system is improved by adopting CCI canceller. When we adopt the RAKE receiver to mitigate the multipath fading, the error performance is improved and the amount of improvement is proportional ot the number of taps L in the case that each tap contains a signal component and the better of improvement can be obtained, the smaller of the SNR difference in each tap. The system capacity is more increased when the CCI canceller and the RAKE receiver is used in cascade.

• The KIPS Transactions:PartC
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• v.11C no.1
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• pp.141-148
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• 2004

Recently, the demand of broadband communications such as high-speed internet, HDTV, 3D-HDTV and ATM backbone network has been increased drastically. For transmitting the broad-bandwidth data using wireless network, it is needed to use ka-band frequency. However, the use of this ka-band frequency is seriously affected to the received data performance by rain fading and atmospheric propagation loss at the Ka-band satellite communication link. So, we need adaptive MODEM to endure the degraded performance by channel environment. In this paper, we will present the structure and design of the 155Mbps adaptive Modem adaptively compensated against channel environment. In order to compensate the rain attenuation over the ka-band wireless channel link, the adaptive coding schemes with variable coding rates and the multiple modulation schemes such as trellis coded 8-PSK, QPSK, and BPSK are adopted. And the blind demodulation scheme is proposed to demodulate without Information of modulation mode at the multi-mode demodulator, and the fast phase ambiguity resolving scheme is proposed. The design and simulation results of adaptive Modem by SPW model are provided. This 155Mbps adaptive MODEM was designed and implemented by single ASIC chip with the $0.25\mu{m}$ CMOS standard cell technology and 950 thousand gates.