VPA를 이용한 트랙터 좌석 진동의 전달 특성 구명

이주완,김경욱 한국농업기계학회 2001 바이오시스템공학 Vol.26 No.3

S6K1 Phosphorylation of H2B Mediates EZH2 Trimethylation of H3: A Determinant of Early Adipogenesis

Yi, S.,Um, S.,Lee, J.,Yoo, J.,Bang, S.,Park, E.,Lee, M.,Nam, K.,Jeon, Y.,Park, J.,You, J.,Lee, S.J.,Bae, G.U.,Rhie, J.,Kozma, Sara C.,Thomas, G.,Han, J.W. Cell Press 2016 Molecular Cell Vol.62 No.3

S6K1 has been implicated in a number of key metabolic responses, which contribute to obesity. Critical among these is the control of a transcriptional program required for the commitment of mesenchymal stem cells to the adipocytic lineage. However, in contrast to its role in the cytosol, the functions and targets of nuclear S6K1 are unknown. Here, we show that adipogenic stimuli trigger nuclear translocation of S6K1, leading to H2BS36 phosphorylation and recruitment of EZH2 to H3, which mediates H3K27 trimethylation. This blocks Wnt gene expression, inducing the upregulation of PPARγ and Cebpa and driving increased adipogenesis. Consistent with this finding, white adipose tissue from S6K1-deficient mice exhibits no detectable H2BS36 phosphorylation or H3K27 trimethylation, whereas both responses are highly elevated in obese humans or in mice fed a high-fat diet. These findings define an S6K1-dependent mechanism in early adipogenesis, contributing to the promotion of obesity.

A FUZZY NEURAL NETWORK-BASED DECISION OF ROAD IMAGE QUALITY FOR THE EXTRACTION OF LANE-RELATED INFORMATION

U.-K. YI,J.W. LEE,K R. BAEK 한국자동차공학회 2005 International journal of automotive technology Vol.6 No.1

We propose a fuzzy neural network (FNN) theory capable of deciding the quality of a road image prior to extracting lane-related information. The accuracy of lane-related information obtained by image processing depends on the quality of the raw images, which can be classified as good or bad according to how visible the lane marks on the images are Enhancing the accuracy of the information by an image-processing algorithm is limited due to noise corruption which makes image processing difficult. The FNN, on the other hand, decides whether road images are good or bad with respect to the degree of noise corruption. A cumulative distribution function (CDF), a function of edge histogram, is utilized to extract input parameters from the FNN according to the fact that the shape of the CDF is deeply correlated to the road image quality. A suitability analysis shows that this deep correlation exists between the parameters and the image quality. The input pattern vector of the FNN consists of nine parameters in which eight parameters are from the CDF and one is from the intensity distnbution of raw images. Experimental results showed that the proposed FNN system was quite successful. We carried out simulations with real images taken in various lighting and weather conditions, and obtained successful decision-making about 99% of the time.

A FUZZY NEURAL NETWORK-BASED DECISION OF ROAD IMAGE QUALITY FOR THE EXTRACTION OF LANE-RELATED INFORMATION

YI U. K.,LEE J. W.,BAEK K. R. The Korean Society of Automotive Engineers 2005 International journal of automotive technology Vol.6 No.1

We propose a fuzzy neural network (FNN) theory capable of deciding the quality of a road image prior to extracting lane-related information. The accuracy of lane-related information obtained by image processing depends on the quality of the raw images, which can be classified as good or bad according to how visible the lane marks on the images are. Enhancing the accuracy of the information by an image-processing algorithm is limited due to noise corruption which makes image processing difficult. The FNN, on the other hand, decides whether road images are good or bad with respect to the degree of noise corruption. A cumulative distribution function (CDF), a function of edge histogram, is utilized to extract input parameters from the FNN according to the fact that the shape of the CDF is deeply correlated to the road image quality. A suitability analysis shows that this deep correlation exists between the parameters and the image quality. The input pattern vector of the FNN consists of nine parameters in which eight parameters are from the CDF and one is from the intensity distribution of raw images. Experimental results showed that the proposed FNN system was quite successful. We carried out simulations with real images taken in various lighting and weather conditions, and obtained successful decision-making about $99\%$ of the time.

Preoperative alpha-fetoprotein and 18F-FDG PET predict the tumor recurrence after adult Living donor Liver transplantation for hepatocellular carcinoma beyond Milan criteria (초)

( K. S. Suh ),( N. J. Yi ),( Y. M. Jeon ),( G. Hong ),( K. W. Lee ),( K. U. Lee ) 대한간학회 2010 Clinical and Molecular Hepatology(대한간학회지) Vol.16 No.3(S)

EXTRACTION OF LANE-RELATED INFORMATION AND A REAL-TIME IMAGE PROCESSING ONBOARD SYSTEM

YI U. K.,LEE W. The Korean Society of Automotive Engineers 2005 International journal of automotive technology Vol.6 No.2

The purpose of this paper is two-fold: 1) A novel algorithm in order to extract lane-related information from road images is presented; 2) Design specifications of an image processing onboard unit capable of extracting lane­related information in real-time is also presented. Obtaining precise information from road images requires many features due to the effects of noise that eventually leads to long processing time. By exploiting a FPGA and DSP, we solve the problem of real-time processing. Due to the fact that image processing of road images relies largely on edge features, the FPGA is adopted in the hardware design. The schematic configuration of the FPGA is optimized in order to perform 3 $\times$ 3 Sobel edge extraction. The DSP carries out high-level image processing of recognition, decision, estimation, etc. The proposed algorithm uses edge features to define an Edge Distribution Function (EDF), which is a histogram of edge magnitude with respect to the edge orientation angle. The EDF enables the edge-related information and lane-related to be connected. The performance of the proposed system is verified through the extraction of lane-related information. The experimental results show the robustness of the proposed algorithm and a processing speed of more than 25 frames per second, which is considered quite successful.

EXTRACTION OF LANE-RELATED INFORMATION AND A REAL TIME IMAGE PROCESSING ONBOARD SYSTEM

U. K. YI,J. W. LEE 한국자동차공학회 2005 International journal of automotive technology Vol.6 No.2

The purpose of this paper is two-fold: 1) A novel algorithm in order to extract lane-related information from road images is presented; 2) Design specifications of an image processing onboard unit capable of extracting lane-related information in real-time is also presented. Obtaining precise information from road images requires many features due to the effects of noise that eventually leads to long processing time. By exploiting a FPGA and DSP, we solve the problem of real-time processing. Due to the fact that image processing of road images relies largely on edge features, the FPGA is adopted in the hardware design. The schematic configuration of the FPGA is optimized in order to perform 3 × 3 Sobel edge extraction. The DSP carries out high-level image processing of recognition, decision, estimation, etc. The proposed algorithm uses edge features to define an Edge Distribution Function (EDF), which is a histogram of edge magnitude with respect to the edge orientation angle. The EDF enables the edge-related information and lane-related to be connected. The performance of the proposed system is verified through the extraction of lane-related information. The experimental results show the robustness of the proposed algorithm and a processing speed of more than 25 frames per second, which is considered quite successful.

The complete chloroplast genome sequence of Abies nephrolepis (Pinaceae: Abietoideae)

Yi, D.K.,Choi, K.,Joo, M.,Yang, J.C.,Mustafina, F.U.,Han, J.S.,Son, D.C.,Chang, K.S.,Shin, C.H.,Lee, Y.M. Korean Biodiversity Information Facility 2016 Journal of Asia-Pacific biodiversity(Online) Vol.9 No.2

The plant chloroplast (cp) genome has maintained a relatively conserved structure and gene content throughout evolution. Cp genome sequences have been used widely for resolving evolutionary and phylogenetic issues at various taxonomic levels of plants. Here, we report the complete cp genome of Abies nephrolepis. The A. nephrolepis cp genome is 121,336 base pairs (bp) in length including a pair of short inverted repeat regions (IRa and IRb) of 139 bp each separated by a small single copy (SSC) region of 54,323 bp (SSC) and a large single copy region of 66,735 bp (LSC). It contains 114 genes, 68 of which are protein coding genes, 35 tRNA and four rRNA genes, six open reading frames, and one pseudogene. Seventeen repeat units and 64 simple sequence repeats (SSR) have been detected in A. nephrolepis cp genome. Large IR sequences locate in 42-kb inversion points (1186 bp). The A. nephrolepis cp genome is identical to Abies koreana's which is closely related to taxa. Pairwise comparison between two cp genomes revealed 140 polymorphic sites in each. Complete cp genome sequence of A. nephrolepis has a significant potential to provide information on the evolutionary pattern of Abietoideae and valuable data for development of DNA markers for easy identification and classification.

Selective antitumor effect of neural stem cells expressing cytosine deaminase and interferon-beta against ductal breast cancer cells in cellular and xenograft models

Yi, B.R.,Hwang, K.A.,Aboody, K.S.,Jeung, E.B.,Kim, S.U.,Choi, K.C. Elsevier 2014 Stem cell research Vol.12 No.1

Due to their inherent tumor-tropic properties, genetically engineered stem cells may be advantageous for gene therapy treatment of various human cancers, including brain, liver, ovarian, and prostate malignancies. In this study, we employed human neural stem cells (HB1.F3; hNSCs) transduced with genes expressing Escherichia coli cytosine deaminase (HB1.F3.CD) and human interferon-beta (HB1.F3.CD.IFN-β) as a treatment strategy for ductal breast cancer. CD can convert the prodrug 5-fluorocytosine (5-FC) to its active chemotherapeutic form, 5-fluorouracil (5-FU), which induces a tumor-killing effect through DNA synthesis inhibition. IFN-β also strongly inhibits tumor growth by the apoptotic process. RT-PCR confirmed that HB1.F3.CD cells expressed CD and HB1.F3.CD.IFN-β cells expressed both CD and IFN-β. A modified transwell migration assay showed that HB1.F3.CD and HB1.F3.CD.IFN-β cells selectively migrated toward MCF-7 and MDA-MB-231 human breast cancer cells. In hNSC-breast cancer co-cultures the viability of breast cancer cells which were significantly reduced by HB1.F3.CD or HB1.F3.CD.IFN-β cells in the presence of 5-FC. The tumor inhibitory effect was greater with the HB1.F3.CD.IFN-β cells, indicating an additional effect of IFN-β to 5-FU. In addition, the tumor-tropic properties of these hNSCs were found to be attributed to chemoattractant molecules secreted by breast cancer cells, including stem cell factor (SCF), c-kit, vascular endothelial growth factor (VEGF), and VEGF receptor 2. An in vivo assay performed using MDA-MB-231/luc breast cancer mammary fat pad xenografts in immunodeficient mice resulted in 50% reduced tumor growth and increased long-term survival in HB1.F3.CD and HB1.F3.CD.IFN-β plus 5-FC treated mice relative to controls. Our results suggest that hNSCs genetically modified to express CD and/or IFN-β genes can be used as a novel targeted cancer gene therapy.

Novel low cost chemical texturing for very large area industrial multi-crystalline silicon solar cells

Gangopadhyay, U,Dhungel, S K,Kim, K,Manna, U,Basu, P K,Kim, H J,Karunagaran, B,Lee, K S,Yoo, J S,Yi, J Institute of Physics 2005 Semiconductor science and technology Vol.20 No.9

<P>Multi-crystalline silicon surface etching without grain-boundary delineation is a challenging task for the fabrication of high efficiency solar cells. The use of sodium hydroxide–sodium hypochlorite (NaOH–NaOCl) solution for texturing a multi-crystalline silicon wafer surface in a solar cell fabrication line is reported in this paper. The optimized etching solution of NaOH–NaOCl does not have any effect on multi-crystalline silicon grain boundaries and it also has excellent isotropic etch characteristics, which ultimately helps to achieve higher values of performance parameters, especially the open circuit voltage (<I>V</I><SUB>oc</SUB>) and fill factor (FF), than those in the case of conventional silicon texturing. Easy control over the reaction of the NaOH–NaOCl solution is also one of the major advantages due to which sophistication in controlling the temperature of the etching bath is not required for the industrial batch process. The FTIR analysis of the silicon surface after etching with the current approach shows the formation of Si–Cl bonds, which improves the quality of the diffused junction due to chlorine gettering during diffusion. We are the first to report 14–14.5% efficiency of very large area (150 mm ? 150 mm) multi-crystalline silicon solar cells using a NaOH–NaOCl texturing approach in an industrial production line with a yield greater than 95%.</P>