• Title/Summary/Keyword: EM Algorithm

Search Result 375, Processing Time 0.024 seconds

Identification of Novel SNPs in Bovine Insulin-like Growth Factor Binding Protein-3 (IGFBP3) Gene

  • Kim, J.Y.;Yoon, D.H.;Park, B.L.;Kim, L.H.;Na, K.J.;Choi, J.G.;Cho, C.Y.;Lee, H.K.;Chung, E.R.;Sang, B.C.;Cheong, I.J.;Oh, S.J.;Shin, Hyoung Doo
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.18 no.1
    • /
    • pp.3-7
    • /
    • 2005
  • The insulin-like growth factors (IGFs), their receptors, and their binding proteins play key roles in regulating cell proliferation and apoptosis. Insulin-like growth factor binding protein-3 (IGFBP3, OMIM #146732) is one of the proteins that bind to the IGFs. IGFBP3 is a modulator of IGF bioactivity, and direct growth inhibitor in the extravascular tissue compartment. We identified twenty-two novel single nucleotide polymorphisms (SNPs) in IGFBP3 gene in Korean cattle (Hanwoo, Bos taurus coreanae) by direct sequencing of full gene including -1,500 bp promoter region. Among the identified SNPs, five common SNPs were screened in 650 Korean cattle; one SNP in promoter (IGFBP3 G-854C), one in 5'UTR region (IGFBP3 G-100A), two in intron 1 (IGFBP3 G+421T, IGFBP3 T+1636A), and one in intron 2 (IGFBP3 C+3863A). The frequencies of each SNP were 0.357 (IGFBP3 G-854C), 0.472 (IGFBP3 G-100A), 0.418 (IGFBP3 G+421T), 0.363 (IGFBP3 T+1636A) and 0.226 (IGFBP3 C+3863A), respectively. Haplotypes and their frequencies were estimated by EM algorithm. Six haplotypes were constructed with five SNPs and linkage disequilibrium coefficients (|D'|) between SNP pairs were also calculated. The information on SNPs and haplotypes in IGFBP3 gene could be useful for genetic studies of this gene.

Efficient Speech Enhancement based on left-right HMM with State Sequence Decision Using LRT (좌-우향 은닉 마코프 모델에서 상태결정을 이용한 음질향상)

  • 이기용
    • The Journal of the Acoustical Society of Korea
    • /
    • v.23 no.1
    • /
    • pp.47-53
    • /
    • 2004
  • We propose a new speech enhancement algorithm based on left-right Hidden Markov Model (HMM) with state decision using Log-likelihood Ratio Test (LRT). Since the conventional HMM-based speech enhancement methods try to improve speech quality for all states, they introduce huge computational loads inappropriate to real-time implementation. In the left-right HMM, only the current and the next state are considered for a possible state transition so to reduce the computational complexity. In this paper, we propose a method to decide the current state by using the LRT on the previous state. Experimental results show that the proposed method improves the speed up to 60% with 0.2∼0.4 dB degradation of speech quality compared to the conventional method.

Contrast Enhancement based on Gaussian Region Segmentation (가우시안 영역 분리 기반 명암 대비 향상)

  • Shim, Woosung
    • Journal of Broadcast Engineering
    • /
    • v.22 no.5
    • /
    • pp.608-617
    • /
    • 2017
  • Methods of contrast enhancement have problem such as side effect of over-enhancement with non-gaussian histogram distribution, tradeoff enhancement efficiency against brightness preserving. In order to enhance contrast at various histogram distribution, segmentation to region with gaussian distribution and then enhance contrast each region. First, we segment an image into several regions using GMM(Gaussian Mixture Model)fitting by that k-mean clustering and EM(Expectation-Maximization) in $L^*a^*b^*$ color space. As a result region segmentation, we get the region map and probability map. Then we apply local contrast enhancement algorithm that mean shift to minimum overlapping of each region and preserve brightness histogram equalization. Experiment result show that proposed region based contrast enhancement method compare to the conventional method as AMBE(AbsoluteMean Brightness Error) and AE(Average Entropy), brightness is maintained and represented detail information.

Design of a Multi-Stripline Loaded On-Glass Antenna for T-DMB Applications (다중 선로가 로딩된 T-DMB 수신용 차량 글래스 안테나 설계)

  • Kang, Woo-Joong;Kay, Young-Chul;Park, Seul-Gi;Oh, Jung-Hun;Choo, Ho-Sung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.20 no.7
    • /
    • pp.664-672
    • /
    • 2009
  • In this paper we propose an on-glass antenna which consists of conducting dual center striplines and multi-loaded striplines. Multi-loaded striplines and dual center lines were employed for achieving a broad matching bandwidth and improving a vertical radiation gain, respectively. The detail design parameters were determined using the Pareto genetic algorithm with an full wave EM simulator. The optimized design was built and installed on a commercial vehicle, and the antenna performances such as the return loss and the radiation gain were measured in a semi-anechoic chamber. The measurement results showed the matching bandwidth($S_{11}$<-3 dB) of about 49 % in the T-DMB frequency band, the vertical gain of about -3 dBi along the bore-sight direction, and the average gain of about -10 dBi along the azimuth direction.

Demonstration of Voltage Control of DC Distribution System Using Real-time DC Network Analysis Applications (실시간 DC 계통해석 응용프로그램을 이용한 DC 배전망 전압제어 실증 연구)

  • Kim, Hong-joo;Cho, Young-pyo;Cho, Jin-tae;Kim, Ju-yong
    • KEPCO Journal on Electric Power and Energy
    • /
    • v.5 no.4
    • /
    • pp.275-286
    • /
    • 2019
  • This paper presents real-time Direct Current (DC) network analysis applications for operation of DC distribution system or DC microgrid. These applications are installed on central Energy Management System (EMS) and provide solutions of DC network operation. To analysis DC distribution network, this paper proposes composition and sequence of applications. Algorithm of applications is presented in this paper. Demonstration tests are performed on DC distribution site in Gochang Power Testing Center of Korea Electric Power Corporation (KEPCO). To verify the performance, developed DC applications installed on EMS. Scenarios for demonstration test of voltage control are presented. Finally, measured data, application output data and simulation data (by PSCAD/EMTDC) are compared and analyze accuracy of applications.

SPATIAL AND ENERGY RESOLUTIONS OF A HEXAGONAL ANIMAL PET SCANNER BASED ON LGSO CRYSTAL AND FLAT-PANEL PMT

  • Lee, Chan-Mi;Hong, Seong-Jong;Yoon, Hyun-Suk;Ito, Mikiko;Kwon, Sun-Il;Park, Sang-Keun;Lee, Dong-Soo;Sim, Kwang-Souk;Lee, Jae-Sung
    • Nuclear Engineering and Technology
    • /
    • v.44 no.1
    • /
    • pp.53-60
    • /
    • 2012
  • The aim of this study was to explore the spatial and energy resolutions of a PET scanner that we have recently developed. The scanner, which consists of six detector modules with 1-layer LGSO crystals, has a hexagonal configuration with a faceto- face distance of 86.4 mm between two opposite PET modules; such properties facilitate the imaging of small animals. A $^{22}Na$ point source was employed to estimate horizontal and vertical spatial resolutions. To assess the energy resolution, a uniform $^{18}F$ cylindrical phantom was scanned. A software-based spectrum analysis of list-mode data was used to assign a local energy window centered on the photopeak position for every single crystal. For the image reconstruction, an ML-EM algorithm was used. The spatial resolutions at the center of the scanner were 0.99 mm in the horizontal direction and 1.13 mm in the vertical direction. The energy resolution averaged over each PMT ranged from 13.3%-14.3%, which gave an average value of 13.8%. These results show that this simple system is promising for small animal imaging with excellent spatial and energy resolutions.

Genetic Relationship between Ultrasonic and Carcass Measurements for Meat Qualities in Korean Steers

  • Lee, D.H.;Kim, H.C.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.17 no.1
    • /
    • pp.7-12
    • /
    • 2004
  • Real time ultrasonic measurements for 13th rib fat thickness (LBF), longissimus muscle area (LEMA) and marbling score (LMS) of live animal at pre-harvest and subsequent carcass measurements for fat thickness (BF), longissimus muscle area (EMA), marbling score (MS) as well as body weight of live animal, carcass weight (CW), dressing percentage (DP), and total merit index (TMI) on 755 Korean beef steers were analyzed to estimate genetic parameters. Data were analyzed using multivariate animal models with an EM-REML algorithm. Models included fixed effects for year-season of birth, location of birth, test station, age of dam, linear and quadratic covariates for age or body weight at slaughter and random animal and residual effects. The heritability estimates for LEMA, LBF and LMS on RTU scans were 0.17, 0.41 and 0.55 in the age-adjusted model (Model 1) and 0.20, 0.52 and 0.55 in the weight-adjusted model (Model 2), respectively. The Heritability estimates for subsequent traits on carcass measures were 0.20, 0.38 and 0.54 in Model 1 and 0.23, 0.46 and 0.55 in Model 2, respectively. Genetic correlation estimate between LEMA and EMA was 0.81 and 0.79 in Model 1 and Model 2, respectively. Genetic correlation estimate between LBF and BF were high as 0.97 in Model 1 and 0.98 in Model 2. Real time ultrasonic marbling score were highly genetically correlated to carcass MS of 0.89 in Model 1 and 0.92 in Model 2. These results indicate that RTU scans would be alterative to carcass measurement for genetic evaluation of meat quality in a designed progeny-testing program in Korean beef cattle.

Joint model of longitudinal data with informative observation time and competing risk (결시적 자료에서 관측 중단을 모형화하기 위해 사용되는 경쟁 위험의 적용과 결합 모형)

  • Kim, Yang-Jin
    • The Korean Journal of Applied Statistics
    • /
    • v.29 no.1
    • /
    • pp.113-122
    • /
    • 2016
  • Longitudinal data often occur in prospective follow-up studies. Joint model for longitudinal data and failure time has been applied on several works. In this paper, we extend it to the case where longitudinal data involve informative observation time process as well as competing risks survival times. We use a likelihood approach and derive an EM algorithm to obtain maximum likelihood estimate of parameters. A suggested joint model allows us to make inferences for three components: longitudinal outcome, observation time process and competing risk failure time. In addition, we can test the association among these components. In this paper, liver cirrhosis patients' data is analyzed. The relationship between prothrombin times measured at irregular visiting times and drop outs is investigated with a joint model.

Haplotype Analysis and Single Nucleotide Polymorphism Frequency of Organic Cation Transporter Gene (OCT1 and 2) in Korean Subjects

  • Kim, Se-Mi;Lee, Sang-No;Yoon, Hwa;Kang, Hyun-Ah;Cho, Hea-Young;Lee, Il-Kwon;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
    • /
    • v.39 no.5
    • /
    • pp.345-351
    • /
    • 2009
  • Organic cation transporters (OCTs) are important for absorption, elimination of many endogenous small organic cations as well as a wide array of drugs and environmental toxins. This gene is located in a cluster on chromosome 6 and OCTs are in major organs such as intestine, liver, kidney, brain and placenta. Therefore, expression levels and function of OCTs directly affect plasma levels and intracellular concentrations of drugs and thereby determine therapeutic response. The aim of this study was to investigate the frequency of the SNPs on OCT1 (C181T and C1022T) and OCT2 (G808T) to analyze haplotype frequency in healthy Korean population. Human subjects have been genotyped for OCT1 (C181T for 195 subjects and C1022T for 825 subjects), using polymerase chain reaction-based diagnostic tests (RFLP). And for OCT2 (G808T), a total of 861 subjects have been genotyped, using pyrosequencing method. Haplotype was statistically inferred using an algorithm based on the expectation-maximization (EM). OCT1 C181T genotyping showed 100% homozygous wild-type (C/C). OCT1 C1022T genotyping showed wild-type (C/C), heterozygous (C/T) and homozygous mutant-type (T/T) and each accounted for 72.1, 24.5 and 3.4%, respectively. OCT2 G808T genotyping results also showed homozygous wild-type (G/G), heterozygous (G/T) and homozygous mutant-type (T/T) and each took 81.8, 17.9 and 0.3%, respectively. Based on these genotype data, haplotype analysis between OCT1 C181T and OCT1 C1022T has proceeded. The result has revealed that linkage disequilibrium between alleles is not obvious (P=0.0122).

Measurements and Statistical Modeling of Ignition Noise from Vehicle (자동차 점화계통에서 발생된 전자파 잡음의 측정 및 통계적 모형)

  • 김종호;윤현보;백락준;우종우
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.8 no.4
    • /
    • pp.390-402
    • /
    • 1997
  • The ignition noises from the vehicle are measured and the measurement data are statistically treated for modeling. The low-noise amplifier and band-pass filter are added between the receiver and the three axes antenna for low noise level measurement and the APD and PSD are measured in 800 MHz frequency range. The measured APD curves can be expressed in terms of sensitivity study of each model through 3(class A) or 6(Class B) parameters variation, and these optimal parameter can easily be calculated by using the Composite Approximation Algorithm. The selected APD parameter can be used for making the Data Base EM-environments and also applied to determine the output and sensitivity margin for the transmitter and receiver. 'Digital microwave transmission systems are equipped with equalizer against fading during multipath fading. In this paper, we proposed variable reference tap position equalizer that varies the reference tap according to fading type to archive better performance. We got the perf?mance improvement about 4~5 dB in MP condition and 2~3 dB in NMP condition from simulation results.

  • PDF