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Improved ADALINE Harmonics Extraction Algorithm for Boosting Performance of Photovoltaic Shunt Active Power Filter under Dynamic Operations

  • Mohd Zainuri, Muhammad Ammirrul Atiqi;Radzi, Mohd Amran Mohd;Soh, Azura Che;Mariun, Norman;Rahim, Nasrudin Abd.
    • Journal of Electrical Engineering and Technology
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    • v.11 no.6
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    • pp.1714-1728
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    • 2016
  • This paper presents improved harmonics extraction based on Adaptive Linear Neuron (ADALINE) algorithm for single phase photovoltaic (PV) shunt active power filter (SAPF). The proposed algorithm, named later as Improved ADALINE, contributes to better performance by removing cosine factor and sum of element that are considered as unnecessary features inside the existing algorithm, known as Modified Widrow-Hoff (W-H) ADALINE. A new updating technique, named as Fundamental Active Current, is introduced to replace the role of the weight factor inside the previous updating technique. For evaluation and comparison purposes, both proposed and existing algorithms have been developed. The PV SAPF with both algorithms was simulated in MATLAB-Simulink respectively, with and without operation or connection of PV. For hardware implementation, laboratory prototype has been developed and the proposed algorithm was programmed in TMS320F28335 DSP board. Steady state operation and three critical dynamic operations, which involve change of nonlinear loads, off-on operation between PV and SAPF, and change of irradiances, were carried out for performance evaluation. From the results and analysis, the Improved ADALINE algorithm shows the best performances with low total harmonic distortion, fast response time and high source power reduction. It performs well in both steady state and dynamic operations as compared to the Modified W-H ADALINE algorithm.

Investigating InSnZnO as an Active Layer for Non-volatile Memory Devices and Increasing Memory Window by Utilizing Silicon-rich SiOx for Charge Storage Layer

  • Park, Heejun;Nguyen, Cam Phu Thi;Raja, Jayapal;Jang, Kyungsoo;Jung, Junhee;Yi, Junsin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.324-326
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    • 2016
  • In this study, we have investigated indium tin zinc oxide (ITZO) as an active channel for non-volatile memory (NVM) devices. The electrical and memory characteristics of NVM devices using multi-stack gate insulator SiO2/SiOx/SiOxNy (OOxOy) with Si-rich SiOx for charge storage layer were also reported. The transmittance of ITZO films reached over 85%. Besides, ITZO-based NVM devices showed good electrical properties such as high field effect mobility of 25.8 cm2/V.s, low threshold voltage of 0.75 V, low subthreshold slope of 0.23 V/dec and high on-off current ratio of $1.25{\times}107$. The transmission Fourier Transform Infrared spectroscopy of SiOx charge storage layer with the richest silicon content showed an assignment at peaks around 2000-2300 cm-1. It indicates that many silicon phases and defect sources exist in the matrix of the SiOx films. In addition, the characteristics of NVM device showed a retention exceeding 97% of threshold voltage shift after 104 s and greater than 94% after 10 years with low operating voltage of +11 V at only 1 ms programming duration time. Therefore, the NVM fabricated by high transparent ITZO active layer and OOxOy memory stack has been applied for the flexible memory system.

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The Effects of a Thermal Annealing Process in IGZO Thin Film Transistors

  • Kim, Hyeong-Jun;Park, Hyung-Youl;Park, Jin-Hong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.289.2-289.2
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    • 2016
  • In-Ga-Zn-O(IGZO) receive great attention as a channel material for thin film transistors(TFTs) as next-generation display panel backplanes due to its superior electrical and physical properties such as a high mobility, low off-current, high sub-threshold slope, flexibility, and optical transparency. For the purpose of fabricating high performance IGZO TFTs, a thermal recovery process above a temperature of $300^{\circ}C$ is required for recovery or rearrangement of the ionic bonding structure. However diffused metal atoms from source/drain(S/D) electrodes increase the channel conductivity through the oxidation of diffused atoms and reduction of $In_2O_3$ during the thermal recovery process. Threshold voltage ($V_{TH}$) shift, one of the electrical instability, restricts actual applications of IGZO TFTs. Therefore, additional investigation of the electrical stability of IGZO TFTs is required. In this paper, we demonstrate the effect of Ti diffusion and modulation of interface traps by carrying out an annealing process on IGZO. In order to investigate the effect of diffused Ti atoms from the S/D electrode, we use secondary ion mass spectroscopy (SIMS), X-ray photoelectron spectroscopy, HSC chemistry simulation, and electrical measurements. By thermal annealing process, we demonstrate VTH shift as a function of the channel length and the gate stress. Furthermore, we enhance the electrical stability of the IGZO TFTs through a second thermal annealing process performed at temperature $50^{\circ}C$ lower than the first annealing step to diffuse Ti atoms in the lateral direction with minimal effects on the channel conductivity.

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Light and bias stability of c-IGO TFTs fabricated by rf magnetron sputtering

  • Jo, Kwang-Min;Lee, Joon-Hyung;Kim, Jeong-Joo;Heo, Young-Woo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.265.2-265.2
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    • 2016
  • Oxide thin film transistors (TFTs) have attracted considerable interest for gate diver and pixel switching devices of the active matrix (AM) liquid crystal display (LCD) and organic light emitting diode (OLED) display because of their high field effect mobility, transparency in visible light region, and low temperature processing below $300^{\circ}C$. Recently, oxide TFTs with polycrystalline In-Ga-O(IGO) channel layer reported by Ebata. et. al. showed a amazing field effect mobility of $39.1cm^2/Vs$. The reason having high field effect mobility of IGO TFTs is because $In_2O_3$ has a bixbyite structure in which linear chains of edge sharing InO6 octahedral are isotropic. In this work, we investigated the characteristics and the effects of oxygen partial pressure significantly changed the IGO thin-films and IGO TFTs transfer characteristics. IGO thin-film were fabricated by rf-magnetron sputtering with different oxygen partial pressure ($O_2/(Ar+O_2)$, $Po_2$)ratios. IGO thin film Varies depending on the oxygen partial pressure of 0.1%, 1%, 3%, 5%, 10% have been some significant changes in the electrical characteristics. Also the IGO TFTs VTH value conspicuously shifted in the positive direction, from -8 to 11V as the $Po_2$ increased from 1% to 10%. At $Po_2$ was 5%, IGO TFTs showed a high drain current on/off ratio of ${\sim}10^8$, a field-effect mobility of $84cm^2/Vs$, a threshold voltage of 1.5V, and a subthreshold slpe(SS) of 0.2V/decade from log(IDS) vs VGS.

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'Inbound Globalization' Model for Enhancing the Global Performance of High-Tech Startups from GRI(Government Research Institutions) with Diagnosing the Its Defects (공공기술기반 기술창업의 현황과 글로벌 성과제고 위한 '국내기반형 글로벌 창업(Inbound Globalization)' 모델 연구)

  • Yang, Youngseok
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.11 no.3
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    • pp.27-35
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    • 2016
  • Ministry of Science, ICT and Future Planning have boosted up launching more 'GRI(Government Research Institute) Spin-off High-tech startup' to accelerate the technology commercialization of GRI technologies via the alternative of high-tech startup since 2101. This paper is proposing to found the global platform of accommodating more successful high-tech startup with diagnosing the current policy platform of launching GRI high-tech startup. This paper deliver the outcomes of case study including FGI research over developing the ideas of the experts for the policy line-up of starting from GRI technologies-Hardware Manufacture-BtoB-Global. The research result suggests that the focus of policy should falls not on the quantitative goals, but on more disruptive successful case through utilizing uprising private equity investment in the early stage of business. One of the best policy brought by this research is 'Inbound Globalization Strategy of bringing global early stage investors in Korea for incubation and investment rather than sending out our startup to global without validation by global investor.

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Long term Rainfall-Runoff Modeling Using Storage Function Method (저류함수를 이용한 일단위 장기유출모의 모형 구축)

  • Sung, Young-Du;Chong, Koo-Yol;Shin, Cheol-Kyun;Park, Jin-Hyeog
    • Journal of Korea Water Resources Association
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    • v.41 no.7
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    • pp.737-746
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    • 2008
  • The purpose of developing a rainfall-runoff and reservoir model is to provide an analysis tool for hydrological engineers in order to forecast discharge of rivers and to accomplish reservoir operations easily and accurately. In this study, based on the short-term rainfall-runoff storage function model which has gained popularity for real time flood forecast in practical water management affairs, a long-term runoff model was developed for the improvement of the calculation method of effective rainfall and percolation at the infiltration area. Annual discharge was simulated for three dam watersheds(Andong, Hapcheon, Milyang) in Nakdong River basin to analyze the accuracy of the developed model and compare it to SSARR model, which is used as the long-term runoff model in current practical water management affairs. As the result of the comparison of hydrographs, SSARR model showed relatively better results. However, it is possible for the developed model to simulate reliable long-term runoff using relatively little available data and is useful for hydrological engineers in practical affairs.

Strategy to Enhance Competitiveness of Textile & Fashion in Taegu Exporting U.S. Market - through Joint Research with the Color Association of the US (CAUS) - (대구 섬유 .패션산업의 대미주 수출 경쟁력 강화 방안 - 미국유행색협회(CAUS)와의 공동조사를 통하여-)

  • 박명애;한영아
    • The Research Journal of the Costume Culture
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    • v.9 no.4
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    • pp.616-628
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    • 2001
  • The purpose of this research is to create a polyester sample book that serves as a point of reference that exporters in the Taegu area can allude to when exporting to the U.S. By getting this project off the ground, we can expect to make a worthy contribution to the manufacture of high-quality, value-added fashion & textile goods. The research was conducted as follows. First, a study was carried out in the local market ensued by consumer surveys with regards to consumer attitude on man-made fibers, market researches, and interviews with experts, all in conjunction with the Color Association of the U.S. Also, a diverse array of fabric swatches were collected from Manhattans fabric wholesalers and then classified by color and fabric type fur the sample book. In short, this research found that man-made fibers have full marketability in the U.S. Thus, in order for Taegus synthetic textile firms to be successful in exporting to the US, it is essential that they come up with fabrics that have properties resembling natural fibers such as having a soft hand, natural sheen, smooth draping, and diverse textures as well as being in line with the current trends. In addition, it is also necessary to develop fabrications that are versatile and functional. Thus, by developing innovative fabrications, the synthetic textile business will turn toward the production of high-quality synthetics and will also provide a platfrom for strengthening the competitive edge of Koreas textile & fashion business.

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Promoting Regional Innovation Projects and Cluster Formation in Korea (지역혁신사업 추진지역의 산업 클러스터 형성여건과 정책적 함의)

  • Kwon, Young-Sub
    • Journal of the Korean Academic Society of Industrial Cluster
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    • v.1 no.1
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    • pp.29-46
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    • 2007
  • The purpose of this paper is to analyses current status and issues of cluster formation and extract policy implications. To this end, the questionnaire which surveyed the level of cluster formation were executed targeting the actors of regional innovation projects(RIPs). The results show that the situations and development stage of the cluster formation between capital region and non-capital region, large cities and small and medium sized cites are different. The level of clustering is also satisfactory, which is a requirement for cluster formation at its early stage. However, the capacity for phase II of cluster growth is not sufficient yet in terns of relationships between ventures and large corporations, institutions supporting management, finance and marketing, researchers from each individual sector of strategic industries and spin-off fines. Therefore, RIPs should be promoted with different policy tools for various regions that are devised according to the varying development stage of each region. The location of RIPs should be determined considering efficiency rather than equity, clustering rather than decentralization, and specialization rather than multiple development. In the long term, developed regions should pursue balanced regional development, with underdeveloped regions targeting specialization.

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Mapping the Polarization of the Radio-Loud Lyman Alpha Nebula B3 J2330+3927

  • Yang, Yujin;You, Chang;Zabludoff, Ann;Smith, Paul;Jannuzi, Buell;Prescott, Moire
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.28.3-29
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    • 2015
  • $Ly{\alpha}$ nebulae, or "$Ly{\alpha}$ blobs", are extended (~100 kpc), bright (L[$Ly{\alpha}$] ~ 1044 erg/s) clouds of $Ly{\alpha}$-emitting gas. The origin of the $Ly{\alpha}$ emission remains unknown, but recent theoretical work suggests that measuring the polarization could discriminate among powering mechanisms. we will discuss current status of $Ly{\alpha}$ polarization observations at high-redshift and our on-going survey program. We will present the first narrow-band, imaging polarimetry of a $Ly{\alpha}$ blob, B3 J2330+3927 at z=3.09, with an embedded, radio-loud AGN (C. You et al. in prep.). The AGN lies near the blob's $Ly{\alpha}$ emission peak and its radio lobes align roughly with the blob's semi-major axis. With the SPOL polarimeter on the MMT telescope, we map the polarization in a grid of circular apertures of radius 0.6" (4.4 kpc), detecting a significant (>$2{\sigma}$) polarization fraction P% in 10 apertures and achieving strong upper-limits (as low as 2%) elsewhere. The degree of the polarization map increases from P% ~ 5% at ~5 kpc from the blob center to ~20% at the outer part (~30 kpc). The detections are distributed asymmetrically, roughly along the blob's major axis. The polarization angles (${\Theta}$) are mostly perpendicular to this axis. These results are consistent with the picture that $Ly{\alpha}$ photons produced at the AGN (or the host galaxy) are resonantly scattered away from the center. Higher polarization fraction on the radio jet suggests that the gas is more optically thin along the jet than the off-axis region.

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Identification of small molecules that inhibit the histone chaperone Asf1 and its chromatin function

  • Seol, Ja-Hwan;Song, Tae-Yang;Oh, Se Eun;Jo, Chanhee;Choi, Ahreum;Kim, Byungho;Park, Jinyoung;Hong, Suji;Song, Ilrang;Jung, Kwan Young;Yang, Jae-Hyun;Park, Hwangseo;Ahn, Jin-Hyun;Han, Jeung-Whan;Cho, Eun-Jung
    • BMB Reports
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    • v.48 no.12
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    • pp.685-690
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    • 2015
  • The eukaryotic genome is packed into chromatin, which is important for the genomic integrity and gene regulation. Chromatin structures are maintained through assembly and disassembly of nucleosomes catalyzed by histone chaperones. Asf1 (anti-silencing function 1) is a highly conserved histone chaperone that mediates histone transfer on/off DNA and promotes histone H3 lysine 56 acetylation at globular core domain of histone H3. To elucidate the role of Asf1 in the modulation of chromatin structure, we screened and identified small molecules that inhibit Asf1 and H3K56 acetylation without affecting other histone modifications. These pyrimidine-2,4,6-trione derivative molecules inhibited the nucleosome assembly mediated by Asf1 in vitro, and reduced the H3K56 acetylation in HeLa cells. Furthermore, production of HSV viral particles was reduced by these compounds. As Asf1 is implicated in genome integrity, cell proliferation, and cancer, current Asf1 inhibitor molecules may offer an opportunity for the therapeutic development for treatment of diseases.