• Journal of Communications and Networks
• /
• v.5 no.2
• /
• pp.174-183
• /
• 2003

Space-Time (ST) codes are known to provide high transmission rates, diversity and coding gains. In this paper, a tight upper bound on the error probability of ST codes over rapid fading channels is presented. Moreover, ST codes suitable for rapid fading channels are presented. These codes are designed using the QPSK and 16-QAM signal constellations. The proposed codes are based on two different encoding schemes. The first scheme uses a single trellis encoder, whereas the second scheme uses the I-Q encoding technique. Code design is achieved via partitioning the signal space such that the design criteria are maximized. As a solution for the decoding problem of I-Q ST codes, the paper introduces a low-complexity decoding algorithm. Results show that the I-Q ST codes using the proposed decoding algorithm outperform singleencoder ST codes with equal complexity. The proposed codes are tested over fading channels with different interleaving conditions, where it is shown that the new codes are robust under such imperfect interleaving conditions.

• Proceedings of the IEEK Conference
• /
• 2001.06a
• /
• pp.105-108
• /
• 2001

In this paper, we suggest more precise performance analysis method of turbo interleavers based on two criteria; performance bounds like Union Bound and weight frequency of codewords. In order to present our new method, we employ block, pseudo random, and so-called prime interleavers in compliance of 3GPP standard, respectively. 3GPP complied turbo encoder, decoder, and AWGN channel are implemented by using MATLAB for our performance analysis. According to our analysis, both criteria should be taken into account coincidently to predict the performance of newly designed interleavers.

• Molecules and Cells
• /
• v.37 no.3
• /
• pp.213-219
• /
• 2014

MicroRNAs (miRNAs) represent a class of small non-coding regulatory RNAs that play important roles in normal hematopoiesis, including erythropoiesis. Although studies have identified several miRNAs that regulate erythroid commitment and differentiation, we do not understand the mechanism by which the crucial erythroid transcription factors, GATA-1and NF-E2 directly regulate and control differentiation via miRNA pathways. In this study, we identified miR-199b-5p as a key regulator of human erythropoiesis, and its expression was up-regulated during the erythroid differentiation of K562 cells. Furthermore, the increase of miR-199b-5p in erythroid cells occurred in a GATA-1- and NF-E2-dependent manner during erythrocyte maturation. Both GATA-1 and NF-E2 bound upstream of the miR-199b gene locus and activated its transcription. Forced expression of miRNA-199b-5p in K562 cells affected erythroid cell proliferation and maturation. Moreover, we identified c-Kit as a direct target of miR-199b-5p in erythroid cells. Taken together, our results establish a functional link among the erythroid transcription factors GATA-1/NF-E2, miR-199b-5p and c-Kit, and provide new insights into the coupling of transcription and post-transcription regulation in erythroid differentiation.

• Korean Journal of Comparative Education
• /
• v.22 no.4
• /
• pp.75-98
• /
• 2012

This study aims to investigate and compare with each other the global scholarship policy of Korea, China, and Japan, which is supported by government, and to suggest the improvement plan of the Global Korea Scholarship(GKS) program in Korea. Based on the results of comparison study with Chinese and Japanese policies, the implications for GKS program are as follows. First, GKS program needs to be redesigned according to the boundaries of in-bound and out-bound countries. Especially, the GKS program for 'neighboring countries' focusing on East Asian countries, could be developed as the Union of East Asian Nations. Second, to maximize the performance of GKS, the government needs to cooperate more actively and systematically among related departments through all the steps as a national foreign policy, that is, from establishing goals to evaluating performance. Third, the perspectives on GKS must be expanded, not just as a kind of scholarship, but as a policy for developing Korean culture and language. Fourth, out-bound GKS programs must be greatly expanded in relation to short-term programs as well as the quality of in-bound GKS programs. Finally, out-bound GKS programs for the Asian developing countries need to be redesigned and operated under the focus of ODA, to support the invited Parties beyond the foreign resource policy.

• Molecules and Cells
• /
• v.41 no.5
• /
• pp.423-435
• /
• 2018

This investigation was aimed at working out the combined role of lncRNA H19, miR-29b and Wnt signaling in the development of colorectal cancer (CRC). In the aggregate, 185 CRC tissues and corresponding para-carcinoma tissues were gathered. The human CRC cell lines (i.e. HT29, HCT116, SW480 and SW620) and normal colorectal mucosa cell line (NCM460) were also purchased. Si-H19, si-NC, miR-29b-3p mimics, miR-29b-3p inhibitor, si-PGRN and negative control (NC) were, respectively, transfected into the CRC cells. Luciferase reporter plasmids were prepared to evaluate the transduction activity of $Wnt/{\beta}-catenin$ signaling pathway, and dual-luciferase reporter gene assay was arranged to confirm the targeted relationship between H19 and miR-29b-3p, as well as between miR-29b-3p and PGRN. Finally, the proliferative and invasive capacities of CRC cells were appraised through transwell, MTT and scratch assays. As a result, overexpressed H19 and down-expressed miR-29b-3p displayed close associations with the CRC patients' poor prognosis (P < 0.05). Besides, transfection with si-H19, miR-29b-3p mimic or si-PGRN were correlated with elevated E-cadherin expression, decreased snail and vimentin expressions, as well as less-motivated cell proliferation and cell metastasis (P < 0.05). Moreover, H19 was verified to directly target miR-29b-3p based on the luciferase reporter gene assay (P < 0.05), and miR-29b-3p also bound to PGRN in a direct manner (P < 0.05). Finally, addition of LiCl ($Wnt/{\beta}-catenin$ pathway activator) or XAV93920 ($Wnt/{\beta}-catenin$ pathway inhibitor) would cause remarkably altered E-cadherin, c-Myc, vimentin and snail expressions, as well as significantly changed transcriptional activity of ${\beta}-catenin/Tcf$ reporter plasmid (P < 0.05). In conclusion, the lncRNA H19/miR-29b-3p/PGRN/Wnt axis counted a great deal for seeking appropriate diagnostic biomarkers and treatment targets for CRC.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.3A
• /
• pp.173-179
• /
• 2002

In this paper, we suggest more precise performance analysis method of turbo interleavers based on two criteria; performance bounds like Union Bound and weight frequency of codewords. In order to present our new method, we employ block pseudo random, and so-called prime interleavers in compliance of 3GPP standard, respectively, We also applied this method to S-random interleavers that have different window size, S. 3GPP complied turbo encoder, decoder, and AWGN channel are implemented by using MATLAB for our performance analysis. According to our analysis, both criteria should be taken into account coincidently to predict the performance of newly designed interleavers.

• Proceedings of the IEEK Conference
• /
• 2004.06a
• /
• pp.11-14
• /
• 2004

Digital Video Broadcasting - Satellite (DVB-S) [1] (EN 300 421(bibliography)) was introduced as a standard in 1994. However, by combing with higher order modulation, promise more powerful alternatives to the DVB-S / DVB-DSNG coding and modulation schemes. Variable rate coding and modulation (VCM) may employed to provide different levels of error protection to different service components. Adaptive coding and modulation (ACM) provides more exact channel protection and dynamic link adaptation to propagation conditions, targeting each individual receiving terminal. By these reasons, DVB-S2 introduced. This paper derives exact symbol error rate(SER) of 16-Amplitude Phase Shift Keying(APSK) modulation by using Craig's formula. 16-APSK modulation is used in DVB-S2. The difference between Union Bound and Craig's formula is 1.26dB in low SNR and 0.1dB in high SNR.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.11 no.7
• /
• pp.1176-1185
• /
• 2000

In this paper, we analyze the distribution of the envelope of the received signal over frequency-nonselective slow Rician fading channels with aadditive white Gaussian noise(AWGN). Especially, we can obtain the error rate performance of noncoherent M-ary FSK(MFSK) over slow and flat Rician fading channels and AWGN from the new probability density function(PDF) of the envelope, not PDF of the instantaneous signal-to-noise ratio(SNR) published before, of the received signal. When coherent MFSK signals experience the Rician fading channel, the performances are derived, using the union bound.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.46 no.4
• /
• pp.64-69
• /
• 2009

Bit-interleaved coded modulation(BICM) applied to Alamouti's orthogonal space-time block code(OSIBC) has a rate loss problem In this paper, we expand orthogonal space-time block code(OSTBC) and apply bit-interleaved coded modulation (BICM) to expanded OSTBC(XOSIBC) to obtain a diversity gain without a rate loss. Binary phase shift keying(BPSK) design example is presented. Simulation results are also provided.

• Journal of Microbiology and Biotechnology
• /
• v.24 no.4
• /
• pp.568-576
• /
• 2014

TIM-1 (also known as KIM-1 and HAVcr-1) is a type I transmembrane glycoprotein member of the TIM family that may play important roles in innate and adaptive immune responses. The overexpression of proteins associated with membrane proteins is a major obstacle to overcome in studies of membrane protein structures and functions. In this study, we successfully coupled the overexpression of the TIM-1 protein with a C-terminal enhanced green fluorescent protein (GFP) tag in Escherichia coli. To the best of our knowledge, this report is the first to describe the overexpression of human TIM-1 in E. coli. The purified TIM-1-EGFP fusion protein recognized and bound directly to apoptotic cells and did not to bind to viable cells. Furthermore, we confirmed that the interactions of TIM-1-EGFP with apoptotic cells were blocked by TIM-1-Fc fusion proteins. This fusion protein represents a readily obtainable source of biologically active TIM-1 that may prove useful in future studies of human TIM-1.