• Title/Summary/Keyword: random process

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Separations and Feature Extractions for Image Signals Using Independent Component Analysis Based on Neural Networks of Efficient Learning Rule (효율적인 학습규칙의 신경망 기반 독립성분분석을 이용한 영상신호의 분리 및 특징추출)

  • Cho, Yong-Hyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.13 no.2
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    • pp.200-208
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    • 2003
  • This paper proposes a separation and feature extraction of image signals using the independent component analysis(ICA) based on neural networks of efficient learning rule. The proposed learning rule is a hybrid fixed-point(FP) algorithm based on secant method and momentum. Secant method is applied to improve the performance by simplifying the 1st-order derivative computation for optimizing the objective function, which is to minimize the mutual informations of the independent components. The momentum is applied for high-speed convergence by restraining the oscillation in the process of converging to the optimal solution. The proposed algorithm has been applied to the composite images generated by random mixing matrix from the 10 images of $512\times512$-pixel. The simulation results show that the proposed algorithm has better performances of the separation speed and rate than those using the FP algorithm based on Newton and secant method. The proposed algorithm has been also applied to extract the features using a 3 set of 10,000 image patches from the 10 fingerprints of $256\times256$-pixel and the front and the rear paper money of $480\times225$-pixel, respectively, The simulation results show that the proposed algorithm has also better extraction speed than those using the another methods. Especially, the 160 basis vectors(features) of $16\times16$-pixel show the local features which have the characteristics of spatial frequency and oriented edges in the images.

Exploring Rape Reports in Newspapers - A Longitudinal Analysis of Four Korean News Dailies between 1990 and 2007 (한국 신문에 나타난 강간보도의 통시적 분석 - 강간통념과 양가적 성차별주의를 중심으로)

  • Lee, Jung-Gyo;Seo, Young-Nam;Choi, Su-Jin
    • Korean journal of communication and information
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    • v.45
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    • pp.425-462
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    • 2009
  • The present study delves into how rape reports are framed in popular Korean newspapers over time. Specifically, the primary purpose of this study was to examine how rape myths and ambivalent sexism and were presented in three Korean newspapers. In order to assess longitudinal trends of rape reports, the sample for the content analysis was drawn from 1990 to 2007. Four newspapers, Chosun-Ilbo, Dongah-Ilbo, Jungang-Ilbo and Hankyoreh, which have been the most popular in terms of circulation and ad revenues, were selected for this longitudinal content analysis. Using random stratified sampling and screening process, A total of 2160 articles were content analyzed for the main study. The results revealed that rape reports appearing in Korean newspapers were overwhelmingly dominated by episodic frame rather than thematic frame. Particularly, It was found that Korean rape reports generally have attributed the cause of rape crimes to the victims. Implications for results were discussed in terms of rape myth and ambivalent sexism theories.

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An Early Spectrum Sensing for Efficient Radio Access in Cloud-Conceptual Base Station Systems (클라우드 기지국 시스템에서 효율적 무선 접속을 위한 이른 스펙트럼 감지 기법)

  • Jo, Gahee;Lee, Jae Won;Na, Jee-Hyeon;Cho, Ho-Shin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.1
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    • pp.68-78
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    • 2013
  • In this paper, we propose an early spectrum sensing(ESS) as an advance preparation for radio-access trial, which enables multi-mode terminals to access the most appropriate radio-access system in a cloud-conceptual base station system where multiple radio access technologies(RATs) coexist. Prior to a random access to one of RATs, a multi-mode terminal conducts a spectrum sensing over entire frequency bands of whole RATs, then select the RAT with the lowest sensing power, that is likely to have the most available spectrum. Thus, an access failure caused by that the selected RAT has no available radio spectrum could be avoidable in advance. In computer simulation, we consider as various RATs as possible. First, circuit and packet systems are taken into consideration. In addition, the packet systems are classified according to the feasibility of carrier aggregation(CA). In case of terminal, three modes are considered with circuit-only, packet-only, and multi-mode. Subsequently, packet traffic is classified into real-time and non-real-time traffic with three different tolerable delay levels. The simulation includes a call process starting with a call generation and ending up with a resource allocation reflecting individual user's QoS requirements and evaluates the proposed scheme in terms of the successful access probability, system access time, system balancing factor and packet loss probability.

Design of a Clock and Data Recovery Circuit Using the Multi-point Phase Detector (다중점 위상검출기를 이용한 클럭 및 데이터 복원회로 설계)

  • Yoo, Sun-Geon;Kim, Seok-Man;Kim, Doo-Hwan;Cho, Kyoung-Rok
    • The Journal of the Korea Contents Association
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    • v.10 no.2
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    • pp.72-80
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    • 2010
  • The 1Gbps clock and data recovery (CDR) circuit using the proposed multi-point phase detector (PD) is presented. The proposed phase detector generates up/down signals comparing 3-point that is data transition point and clock rising/falling edge. The conventional PD uses the pulse width modulation (PWM) that controls the voltage controlled oscillator (VCO) using the width of a pulse period's multiple. However, the proposed PD uses the pulse number modulation (PNM) that regulates the VCO with the number of half clock cycle pulse. Therefore the proposed PD can controls VCO preciously and reduces the jitter. The CDR circuit is tested using 1Gbps $2^{31}-1$ pseudo random bit sequence (PRBS) input data. The designed CDR circuit shows that is capable of recovering clock and data at rates of 1Gbps. The recovered clock jitter is 7.36ps at 1GHz and the total power consumption is about 12mW. The proposed circuit is implemented using a 0.18um CMOS process under 1.8V supply.

A 5.4Gb/s Clock and Data Recovery Circuit for Graphic DRAM Interface (그래픽 DRAM 인터페이스용 5.4Gb/s 클럭 및 데이터 복원회로)

  • Kim, Young-Ran;Kim, Kyung-Ae;Lee, Seung-Jun;Park, Sung-Min
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.2
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    • pp.19-24
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    • 2007
  • With recent advancement of high-speed, multi-gigabit data transmission capabilities, serial links have been more widely adopted in industry than parallel links. Since the parallel link design forces its transmitter to transmit both the data and the clock to the receiver at the same time, it leads to hardware's intricacy during high-speed data transmission, large power consumption, and high cost. Meanwhile, the serial links allows the transmitter to transmit data only with no synchronized clock information. For the purpose, clock and data recovery circuit becomes a very crucial key block. In this paper, a 5.4Gbps half-rate bang-bang CDR is designed for the applications of high-speed graphic DRAM interface. The CDR consists of a half-rate bang-bang phase detector, a current-mirror charge-pump, a 2nd-order loop filter, and a 4-stage differential ring-type VCO. The PD automatically retimes and demultiplexes the data, generating two 2.7Gb/s sequences. The proposed circuit is realized in 66㎚ CMOS process. With input pseudo-random bit sequences (PRBS) of $2^{13}-1$, the post-layout simulations show 10psRMS clock jitter and $40ps_{p-p}$ retimed data jitter characteristics, and also the power dissipation of 80mW from a single 1.8V supply.

Application of Residual Statics to Land Seismic Data: traveltime decomposition vs stack-power maximization (육상 탄성파자료에 대한 나머지 정적보정의 효과: 주행시간 분해기법과 겹쌓기제곱 최대화기법)

  • Sa, Jinhyeon;Woo, Juhwan;Rhee, Chulwoo;Kim, Jisoo
    • Geophysics and Geophysical Exploration
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    • v.19 no.1
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    • pp.11-19
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    • 2016
  • Two representative residual static methods of traveltime decomposition and stack-power maximization are discussed in terms of application to land seismic data. For the model data with synthetic shot/receiver statics (time shift) applied and random noises added, continuities of reflection event are much improved by stack-power maximization method, resulting the derived time-shifts approximately equal to the synthetic statics. Optimal parameters (maximum allowable shift, correlation window, iteration number) for residual statics are effectively chosen with diagnostic displays of CSP (common shot point) stack and CRP (common receiver point) stack as well as CMP gather. In addition to removal of long-wavelength time shift by refraction statics, prior to residual statics, processing steps of f-k filter, predictive deconvolution and time variant spectral whitening are employed to attenuate noises and thereby to minimize the error during the correlation process. The reflectors including horizontal layer of reservoir are more clearly shown in the variable-density section through repicking the velocities after residual statics and inverse NMO correction.

Selective and Random Patterning of Programmed Cell Death in Zebrafish Embryonic Development

  • Hwang, Chang-Nam;Kim, Joon;Lee, Sang-Ho
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2002.11a
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    • pp.118-118
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    • 2002
  • Programmed cell death (PCD) is thought as a well-controlled process by which unwanted cells are selectively eliminated. During the last decade many researches have elucidated molecules and their interactions involved in cell death by using largely in vitro induction of cell death or survival signals in a more defined manner, While these critical information and novel findings provide us with clearer understanding of mechanisms underlying cell death, it does by no means explain how PCD occurs and which cells or tissues are affected during normal embryonic development in vivo. In this study, we used zebrafish to examine whether the PCD is occurring selectively or randomly in developing embryos by whole mount in situ TUNEL analysis with specific markers for neural cells. The result revealed that the degree and distribution of TUNEL staining varied considerably throughout gastrulation stage, and there was also a number of TUNEL-negative embryos. Most of TUNEL-positive cells were scattered randomly throughout the blastoderm. During the gastrulation stage about 75 % of the embryos analyzed exhibited more than 5 TUNEL-positive cells. As the dorsal epiblast begins to thicken rather abruptly near the end of gastrulation, TUNEL-positive cells were mainly located along the dorsal side. Although there were some variations in TUNEL staining during segmentation and pharyngeal stages, TUNEL staining continued to be localized to the central nervous system, and was also detected in the sensory organs, trigeminal ganglions, and the primary sensory neurons. High levels of the cell death in developing brain between 20-somite and prim-6 stages are thought to play a role in the morphogenesis and organization of the brain. At prim-16 stage, cell death is considerably reduced in the brain region. Dying cells are mainly localized to the prospective brain region where ectodermal cells are about to initiate neurogenesis. As development progressed, high levels and more reproducible patterns of cell death were observed in the developing nervous system. Intensive TUNEL staining was restricted to the trigeminal ganglions, the primary sensory neurons, and sensory organs, such as olfactory pits and otic vesicles. Thus, PCD patterning in zebrafish embryos occurs randomly at early stages and becomes restricted to certain region of the embryos. The spatio-temporal pattern of PCD during the early embryonic development in zebrafish will provide basic information for further studies to elucidate genes involved in. regulation of PCD largely unknown in vivo during vertebrate embryogenesis.

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Floating Point Unit Design for the IEEE754-2008 (IEEE754-2008을 위한 고속 부동소수점 연산기 설계)

  • Hwang, Jin-Ha;Kim, Hyun-Pil;Park, Sang-Su;Lee, Yong-Surk
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.48 no.10
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    • pp.82-90
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    • 2011
  • Because of the development of Smart phone devices, the demands of high performance FPU(Floating-point Unit) becomes increasing. Therefore, we propose the high-speed single-/double-precision FPU design that includes an elementary add/sub unit and improved multiplier and compare and convert units. The most commonly used add/sub unit is optimized by the parallel rounding unit. The matrix operation is used in complex calculation something like a graphic calculation. We designed the Multiply-Add Fused(MAF) instead of multiplier to calculate the matrix more quickly. The branch instruction that is decided by the compare operation is very frequently used in various programs. We bypassed the result of the compare operation before all the pipeline processes ended to decrease the total execution time. And we included additional convert operations that are added in IEEE754-2008 standard. To verify our RTL designs, we chose four hundred thousand test vectors by weighted random method and simulated each unit. The FPU that was synthesized by Samsung's 45-nm low-power process satisfied the 600-MHz operation frequency. And we confirm a reduction in area by comparing the improved FPU with the existing FPU.

Effectiveness of alendronate as an adjunct to scaling and root planing in the treatment of periodontitis: a meta-analysis of randomized controlled clinical trials

  • Chen, Jin;Chen, Qian;Hu, Bo;Wang, Yunji;Song, Jinlin
    • Journal of Periodontal and Implant Science
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    • v.46 no.6
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    • pp.382-395
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    • 2016
  • Purpose: Alendronate has been proposed as a local and systemic drug treatment used as an adjunct to scaling and root planing (SRP) for the treatment of periodontitis. However, its effectiveness has yet to be conclusively established. The purpose of the present meta-analysis was to assess the effectiveness of SRP with alendronate on periodontitis compared to SRP alone. Methods: Five electronic databases were used by 2 independent reviewers to identify relevant articles from the earliest records up to September 2016. Randomized controlled trials (RCTs) comparing SRP with alendronate to SRP with placebo in the treatment of periodontitis were included. The outcome measures were changes in bone defect fill, probing depth (PD), and clinical attachment level (CAL) from baseline to 6 months. A fixed-effect or random-effect model was used to pool the extracted data, as appropriate. Mean differences (MDs) with 95% confidence intervals (CIs) were calculated. Heterogeneity was assessed using the Cochrane ${\chi}^2$ and $I^2$ tests. Results: After the selection process, 8 articles were included in the meta-analysis. Compared with SRP alone, the adjunctive mean benefits of locally delivered alendronate were 38.25% for bone defect fill increase (95% CI=33.05%-43.45%; P<0.001; $I^2=94.0%$), 2.29 mm for PD reduction (95% CI=2.07-2.52 mm; P<0.001; $I^2=0.0%$) and 1.92 mm for CAL gain (95% CI=1.55-2.30 mm; P<0.001; $I^2=66.0%$). In addition, systemically administered alendronate with SRP significantly reduced PD by 0.36 mm (95% CI=0.18-0.55 mm; P<0.001; $I^2=0.0%$) and increased CAL by 0.39 mm (95% CI=0.11-0.68 mm; P=0.006; $I^2=6.0%$). Conclusions: The collective evidence regarding the adjunctive use of alendronate locally and systemically with SRP indicates that the combined treatment can improve the efficacy of non-surgical periodontal therapy on increasing CAL and bone defect fill and reducing PD. However, precautions must be exercised in interpreting these results, and multicenter studies evaluating this specific application should be carried out.

People Participation Towards Opisthorchis viverrini Prevention and Control in Chaiyaphum Province, Northeastern Thailand

  • Phongsiripapat, Rutjirapat;Chimplee, Kanokporn;Rujirakul, Ratana;Kaewpitoon, Soraya;Keawpitoon, Natthawut
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.1
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    • pp.177-181
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    • 2016
  • This cross-sectional descriptive and qualitative study was aimed to study the people participation and their approaches toward the human carcinogenic liver fluke, Opisthorchis viverrini, prevention and control in Ban Chaun sub-district administrative organization (BCSAO) and Bamnet Narong sub-district municipality (BNSM), Bamnet Narong district, Chaiyaphum Province, Thailand between June 2013 and February 2014. Participants were purposive selected, included chiefs of sub-district administrative organizations, sub-district municipalities, sub-district health promotion hospitals (SHPHs), heads of village, and a further sample was selected with a multi-stage random sampling for public health volunteers, and villagers. The pre-designed questionnaire contained items for individualized status and the participatory steps of sharing ideas, decision-making, and planning, procession, evaluation, and mutual benefit, for the project O. viverrini prevention and control (POPC). In-depth interviews were used for collection of need approaches to POPC. With 375 participants who completed the questionnaire, it was found that people had a high level regarding to participate in the POPC, particularly in the process stage ($\bar{X}=3.78$, S.D. = 0.56), but the lowest level was found in sharing ideas, decision making, and planning step ($\bar{X}=3.65$, S.D. = 0.63). By comparison, participant status and organization did not significantly differ with people participation. In each step, Ban Chaun sub-district had a high level of participation in the step of sharing ideas, decision making, and planning toward POPC, more than Bamnet Narong sub-district municipality (t=2.20, p=0.028). Approaches for POPC in Ban Chaun sub-district and Bamnet Narong sub-district municipality included requirements for budget support, annual campaigns for liver fluke prevention and control, campaign promotion, risk group observation, home visiting, community rules regarding reducing raw fish consumption in their communities, and a professional public health officer for working in their communities, BCSAO, BNSM, and SHPH, for O. viverrini prevention and control. This study indicates that people realize that eradication of the liver fluke needs a continuous people participation for O. viverrini prevention and control in their communities.