• Title/Summary/Keyword: PSB

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The Photoinactivation of Photosystem II in Leaves: A Personal Perspective

  • Chow, Wah-Soon
    • Journal of Photoscience
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    • v.8 no.2
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    • pp.43-53
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    • 2001
  • a, a parameter that describes how effectively photoinactivated PS II units protect their functional neighbours; car, carotenoids; ΔpH, transthylakoid pH difference; D1 protein, psbA gene product in the PS II reaction centre; f, functional fraction of PS II: F$\_$v//F$\_$m/, the ratio of variable to maximum chlorophyll a fluorescence; k$\_$d/, rate coefficient for degradation of D1 protein; k$\_$i/ and k$\_$r/, rate coefficient for photoinactivation and repair of PS II, respectively; NADP+, oxidized nicontinamide adenine dinucleotide phosphate; P680, the primary electron donor in the PSII reaction centre; Ph, pheophytin; PS, photosystem; Q$\_$A/, first quinone acceptor of an electron in PS II; R$\_$s/, the gross rate of D1 protein synthesis.

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A Voltage and Frequency Controller for Stand Alone Pico Hydro Generation

  • Kasal, Gaurav Kumar;Singh, Bhim
    • Journal of Power Electronics
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    • v.9 no.2
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    • pp.267-274
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    • 2009
  • This paper deals with a voltage and frequency (VF) controller for an isolated power generation system based on an asynchronous generator (AG) driven by a pico hydro turbine. The proposed controller is a combination of a static compensator (STATCOM) and an electronic load controller (ELC) for decoupled control of the reactive and active powers of the AG system to control the voltage and frequency respectively. The proposed generating system along with its VF controller is modeled in MATLAB using SIMULINK and PSB (Power System Block Sets) toolboxes. The performance of the controller is verified for the proposed system and feeding various types of consumer load such as linear/non-linear, balanced/unbalanced and dynamic loads.

Comparison between the Pair Fractions of Dark Matter Halos and Galaxies in Cosmological Simulations

  • An, Sung-Ho;Kim, Juhan;Yoon, Suk-Jin
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.69.1-69.1
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    • 2016
  • We investigate the pair fractions of dark matter halos and galaxies in cosmological simulations. The cosmological simulations are performed by a tree-particle-mesh code GOTPM (Grid-of-Oct-Tree-Particle-Mesh) and the dark matter halos are identified by a halo finding algorithm PSB (Physically Self-Bound). The 'galaxy' pair fractions are obtained from galaxy catalogues of L-Galaxies semi-analytical galaxy formation runs in the Millennium database. We present and compare the pair fractions of the dark matter halos and galaxies as functions of redshifts, halo masses and ambient environments.

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H-Bridge VSC with a T-Connected Transformer for a 3-Phase 4- Wire Voltage and Frequency Controller of an Isolated Asynchronous Generator

  • Kasal, Gaurav Kumar;Singh, Bhim
    • Journal of Power Electronics
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    • v.9 no.1
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    • pp.43-50
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    • 2009
  • This paper deals with a novel solid state controller (NSSC) for an isolated asynchronous generator (IAG) feeding 3-phase 4-wire loads driven by constant power prime movers, such as uncontrolled pico hydro turbines. AC capacitor banks are used to meet the reactive power requirement of the asynchronous generator. The proposed NSSC is realized using a set of IGBTs (Insulated gate bipolar junction transistors) based current controlled 2-leg voltage source converters (CC- VSC) and a DC chopper at its DC bus, which keeps the generated voltage and frequency constant in spite of changes in consumer loads. The neutral point of the load is created using aT-configuration of the transformers. The IAG system is modeled in MATLAB along with Simulink and PSB (power system block set) toolboxes. The simulated results are presented to demonstrate the capability of the isolated generating system consisting of NSSC and IAG driven by uncontrolled pico hydro turbine and feeding 3-phase 4-wire loads.

Comparison on phosphate solubilization ability of Pantoea rodasil and Burkholderia stabilis isolated from button mushroom media (양송이배지로부터 분리한 Pantoea rodasil 와 Burkholderia stabilis의 인산가용화능 비교)

  • Park, Hong-Sin;Yeom, Young-Ho;Yoon, Min-Ho
    • Journal of Mushroom
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    • v.16 no.1
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    • pp.31-38
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    • 2018
  • This study investigated the synergistic effect of single inoculation and co-inoculation of phosphate-solubilizing bacteria (PSB) Pantoea rodasil LH-1and Burkholderia stabilis HS-7. Phosphate-solubilizing abilities of these strains were assessed by measuring phosphorus content in culture media that were singly inoculated or co-inoculated with these strains for 7 days. The co-inoculation of P. rodasil LH-1and B. stabilis HS-7 was found to release the highest content of soluble phosphorus ($783.41{\mu}g\;mL^{-1}$) into the medium, followed by single inoculation of B. stabilis HS-7B ($743.90{\mu}g\;mL^{-1}$) and P. rodasil LH-1 ($736.59{\mu}g\;mL^{-1}$). The highest pH reduction, organic acid production, and glucose consumption were also observed in the medium inoculated with both the strains, compared with that in the medium inoculated with the strain alone. Results of a plant growth promotion bioassay showed 7.7% and 15.5% higher leaf and root growth, respectively, in romaine lettuce co-inoculated with P. rodasil LH-1and B. stabilis HS-7 than those inoculated with the strain alone. However, no significant difference was observed between single inoculation and co-inoculation of these strains with respect to phosphorus release and plant growth. Although the results of the present study did remarkdly not show the synergistic effect of phosphate solubilization by co-inoculation of the PSB strains examined, these results indicate that treatment with PSB exerts a beneficial effect on crop growth.

A systematic study of the Polygonum amphibium L. complex (Polygonaceae) based on chloroplast DNA sequences (엽록체 DNA 염기서열에 근거한 물여뀌 종집단(마디풀과)의 분류학적 연구)

  • Yaqian, Gao;Bhandari, Gauri Shankar;Park, Jin Hee;Park, Chong-Wook
    • Korean Journal of Plant Taxonomy
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    • v.43 no.1
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    • pp.34-45
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    • 2013
  • The Polygonum amphibium complex (Poygonaceae) is a highly polymorphic taxon that can grow in aquatic environments as well as in moist terrestrial habitats. Aquatic and terrestrial plants of the P. amphibium complex vary significantly in morphology and exhibit very complicated patterns of morphological variation, resulting in the description of numerous infra-specific taxa. Principal components analysis of 107 individuals of the P. amphibium complex from Asia and North America using 11 morphological characters showed that the aquatic plants can be discerned from the terrestrial plants by leaf size, shape, and petiole length. In contrast, both aquatic and terrestrial plants collected from the same population or locality shared identical sequences in the matK, psbA-trnH IGS, rbcL-accD IGS and trnL-trnF regions of the chloroplast DNA (cpDNA), suggesting that aquatic and terrestrial forms of the P. amphibium complex are not genetically diverged; morphological differences between the two forms are probably due to the differences in environmental conditions of the habitats. In addition, results from the morphological analysis and the maximum parsimony analysis of the cpDNA data set revealed that the plants from Asia including Korea, Japan, China, Mongolia and Russia Far East are diverged from those in North America and Europe, suggesting that the Asian populations should be recognized as a distinct variety, P. amphibium var. amurense Korsh.

Intraspecific variation and geographic study of Lonicera insularis (Caprifoliaceae) based on chloroplast DNA sequences (엽록체 DNA를 이용한 섬괴불나무(Lonicera insularis Nakai)의 종내변이 및 지리학적 연구)

  • Jeong, Keum Seon;Kim, Mi Sun;Lee, Woong;Pak, Jae-Hong
    • Korean Journal of Plant Taxonomy
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    • v.44 no.3
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    • pp.202-207
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    • 2014
  • Lonicera insularis Nakai (Caprifoliaceae) is Korean endemic plant that lives along the shore of Ulleungdo and Dokdo. The aim of this study is to construct a phylogenetic relationship within six species (L.maackii, L.chrysantha, L.subsessilis, L. harai, L. morrowii) of genus Lonicera L. and Wigela subsessilis as outgroup and intraspecific variation of L. insularis using chloroplast DNA five regions sequences. Sequence analysis revealed that both L. insularis and L. morrowii showed complete homologies in the intergenic regions of trnL-trnF, trnS-trnG, psbM-trnD and matK coding region. However, sequence in the petN-psbM intergenic region showed a single nucleotide difference between both species, thus we designated them as CP01 and CP02. The plants having CP01 are prevalent in the Ulleungdo and Dokdo, while L. insularis and L. morrowii from Ulleungdo and of Dokdo, and Japan have CP02. This confirmed the existence of two cp DNA lineages with different geographical distributions. We can infer the allopatric speciation by geographical barrier. The result will provide the important basal data to study speciation and specie evolution of ocean islands such as Ulleungdo and Dokdo.

A Study on the Factors Affecting the KBS Institution and the Expert Recognition Study on the Improvement of Governance (KBS 제도에 영향을 미치는 요인과 지배구조 개선에 관한 전문가 인식 연구)

  • Park, Jong-Won;Lee, Chang-Hyung;Kim, Kwang-Ho
    • Journal of Digital Contents Society
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    • v.19 no.6
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    • pp.1069-1079
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    • 2018
  • Based on the theory of media governance, we analyzed the factors affecting the KBS system and the perception of the improvement of corporate governance, and suggested ways to improve the governance structure. The results of the study are as follows. First, the factors affecting the KBS system are politics, followed by the public broadcasting itself, that is, professionalism. Political factors were found to be the most influential factors in the public broadcasting KBS Institution. Second, the KBS governance structure, like the BBC, preferred a political independent model, while the board composition and proportions favored a German-style union model involving various stakeholders outside the political circle. Third, the future - oriented KBS governance model requires a change in the civil society (public) sphere that is deviated from the influence of politics and market. In the end, in order for the public broadcasting KBS system to operate stably, the political influence should be reduced, and the role of the government and the market should be controlled by the growth of the public sphere (civil society).

Universal Service and Public Service Broadcasting -In the Age of Media Convergence (융합미디어 시대 보편적 서비스와 공영방송)

  • Kang, Hyung Cheol
    • Korean journal of communication and information
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    • v.67
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    • pp.35-61
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    • 2014
  • This article argues that public service broadcasting (PSB) should be transformed into public service media (PSM) in order to accommodate the concept of universal service in this media convergence age. If we utilize the universal service concept of telecommunications in this purpose, it inevitably constrains the concept to "access to general information" and has a limitation in its scope. In contrast, the application of the broadcast perspective leads to only examine the possibility of expanding the universal service obligation to new platforms, which has been applied to terrestrial broadcasting. As a result, these two approaches have no choice but to stay in limited area such as low-income assistance. Thus, in conclusion, it is necessary to convert PSB to the PSM as a means of providing the socially required content universally, which commercial market cannot easily produce.

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Electrocatalytic activity of the bimetallic Pt-Ru catalysts doped TiO2-hollow sphere nanocomposites (Pt-Ru@TiO2-H 나노구조체촉매의 합성 및 전기화학적 특성평가)

  • Lee, In-Ho;Kwen, Hai-Doo;Choi, Seong-Ho
    • Analytical Science and Technology
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    • v.26 no.1
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    • pp.42-50
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    • 2013
  • This paper describes the electrocatalytic activity for the oxidation of small biomolecules on the surface of Pt-Ru nanoparticles supported by $TiO_2$-hollow sphere prepared for use in sensor applications or fuel cells. The $TiO_2$-hollow sphere supports were first prepared by sol-gel reaction of titanium tetraisopropoxide with poly(styrene-co-vinylphenylboronic acid), PSB used as a template. Pt-Ru nanoparticles were then deposited by chemical reduction of the $Pt^{4+}$ and $Ru^{3+}$ ions onto $TiO_2$-hollow sphere ($Pt-Ru@TiO_2-H$). The prepared $Pt-Ru@TiO_2-H$ nanocomposites were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and elemental analysis. The electrocatalytic efficiency of Pt-Ru nanoparticles was evaluated via ethanol, methanol, dopamine, ascorbic acid, formalin, and glucose oxidation. The cyclic voltammograms (CV) obtained during the oxidation studies revealed that the $Pt-Ru@TiO_2-H$ nanocomposites showed high electrocatalytic activity for the oxidation of biomolecules. As a result, the prepared Pt-Ru catalysts doped onto $TiO_2$-H sphere nanocomposites supports can be used for non-enzymatic biosensor or fuel cell anode electrode.