• Title/Summary/Keyword: green technology

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A B-Spline Higher Order Panel Method Applied to the Radiation Wave Problem for a 2-D Body Oscillating on the Free Surface

  • Hong, D.C.;Lee, C.-S.
    • Journal of Ship and Ocean Technology
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    • v.3 no.4
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    • pp.1-14
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    • 1999
  • The improved Green integral equation using the Kelvin-type Green function in known free of irregular frequencies where the integral over the inner free surface integral is removed from the integral equation, resulting in an overdetermined integral equation. The solution of the overdetermined Green integral equation is shown identical with the solution of the improved Green integral equation Using the B-spline higher order panel method, the overdetermined equation is discretized in two different ways; one of the resulting linear system is square and the other is redundant. Numerical experiments show that the solutions of both are identical. Using the present methods, the exact values and higher derivatives of the potential at any place over the wetted surface of the body can be found with much fewer panels than low order panel method.

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A Study on the Development of G-SEED Accredited Professional System (녹색건축 전문가 자격제도 개발 연구)

  • Lee, Sang Min;Lee, Seung Min
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.13 no.1
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    • pp.32-40
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    • 2014
  • In an effort to resolve environmental pollution problems, developed countries enforce green building certification systems. The same is true in Korea. However compared professional accreditation system to certification systems did not systematically in Korea. Therefore, in accordance with development of green building related systems and technology the requirement for foster green building professionals is urgent. Accordingly this study is purposed to analyze and propose that green building professional accreditation system development and operation of the direction. Through data analysis domestic and international green building professional accreditation system for draw a development plan. And then conduct an expert Delphi survey reflected in the survey results to development plan.

Fabrication and Characteristics of Blue-Green and Green LEDs using ZnSSe:Te Active Layers

  • Lee, Hong-Chan
    • Journal of Advanced Marine Engineering and Technology
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    • v.34 no.7
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    • pp.991-996
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    • 2010
  • Blue-green and green LEDs have been successfully fabricated grown by MBE, which has introduced the $ZnS_ySe_{1-x-y}:Te_x$ (x=0.04, y~0.11-0.14) ternary epilayer as an active layer. From the I-V characteristics, the built-in voltage (~2.1 V) is very small compared to other wide bandgap LEDs, such as commercial InGaN-based LEDs (>3.2 V). From the C-V profiling, the effective carrier concentration in the p-type ZnMgSSe cladding layer was evaluated as ${\sim}2.8{\times}10^{16}\;cm^{-3}$ for the present LEDs.

Solution of the Radiation Problem by the B-Spline Higher Order Kelvin Panel Method for an Oscillating Cylinder Advancing in the Free Surface

  • Hong, Do-Chun;Lee, Chang-Sup
    • Journal of Ship and Ocean Technology
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    • v.6 no.1
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    • pp.34-53
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    • 2002
  • Numerical solution of the forward-speed radiation problem for a half-immersed cylinder advancing in regular waves is presented by making use of the improved Green integral equation in the frequency domain. The B-spline higher order panel method is employed stance the potential and its derivative are unknown at the same time. The present numerical solution of the improved Green integral equation by the B-spline higher order Kelvin panel method is shown to be free of irregular frequencies which are present in the Green integral equation using the forward-speed Kelvin-type Green function.

A study on the HPHT-processed NOUV diamonds by means of their gemological and spectroscopic properties

  • Kim, Young-Chool;Choi, Hyun-Min
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.15 no.3
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    • pp.114-119
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    • 2005
  • This study has been carried out with the eight HPHT processed NOUV diamonds - two yellow, two yellowish green, two green and two orangy yellow color stones. The gemological properties of these diamonds included a highly saturated body color, graphitized fractures around the girdles, tension cracks around crystalline inclusions, long-wave UV with medium yellowish green to a very strong yellowish green luminescence, and short-wave UV with faint yellowish green to a strong yellowish green luminescence. Distinctive features of spectroscopic properties include absorption peaks at 415 nm and 503 nm a strong absorption band at $460{\sim}480nm$ and a H2 center at 986nm. Infrared spectra showed an absorption peak at $1344cm^{-1}$ (C center), which is the characteristics related to single substitutional nitrogen.

Application of the Improved Green Integral Equation to the Radiation-Diffraction Problem for a Floating Ocean Structure in Waves and Current

  • Hong, Do-Chun
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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    • v.3 no.1
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    • pp.14-22
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    • 2000
  • The improved Green integral equation for the calculation of time-harmonic potentials in the radiation diffraction problem about a freely floating body in the presence of moderate or weak current is presented. The forward-speed Green function presented by Brard is used. The correct free surface boundary conditions on the physical free surface are employed as well as an appropriate boundary conditions on the non-physical inner free surface. The default in the existing Green integral equation as well as in the source integral equation is discussed in detail.

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A Study on Introduction and Application of Green SCM (Green SCM 도입 및 적용 방안에 관한 연구)

  • Lee, Gong-Seob
    • Journal of the Korea Safety Management & Science
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    • v.14 no.4
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    • pp.79-83
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    • 2012
  • This study analyzes introduction state of Green SCM technology in domestic and overseas area and suggests how to reduce greenhouse gases of logistics in the future. Thus, introduction state of Green SCM was reviewed by building and integrating logistic-related informatization systems such as WMS and TMS. And how to apply the system to track toxic substance in supply chain was performed to manage toxic substance. Therefore, it will be necessary to develop a device to display and collect vehicle condition & log through OBD-II, which is widely adopted, and hardware to measure, collect, and monitor carbon dioxide emission and power consumption of fixed facilities.

Micro Emulsion Synthesis of LaCoO3 Nanoparticles and their Electrochemical Catalytic Activity

  • Islam, Mobinul;Jeong, Min-Gi;Ghani, Faizan;Jung, Hun-Gi
    • Journal of Electrochemical Science and Technology
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    • v.6 no.4
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    • pp.121-130
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    • 2015
  • The micro emulsion method has been successfully used for preparing perovskite LaCoO3 with uniform, fine-shaped nanoparticles showing high activity as electro catalysts in oxygen reduction reactions (ORRs). They are, therefore, promising candidates for the air-cathode in metal-air rechargeable batteries. Since the activity of a catalyst is highly dependent on its specific surface area, nanoparticles of the perovskite catalyst are desirable for catalyzing both oxygen reduction and evolution reactions. Herein, LaCoO3 powder was also prepared by sol-gel method for comparison, with a broad particle distribution and high agglomeration. The electro catalytic properties of LaCoO3 and LaCoO3-carbon Super P mixture layers toward the ORR were studied comparatively using the rotating disk electrode technique in 0.1 M KOH electrolyte to elucidate the effect of carbon Super P. Koutecky-Levich theory was applied to acquire the overall electron transfer number (n) during the ORR, calculated to be ~3.74 for the LaCoO3-Super P mixture, quite close to the theoretical value (4.0), and ~2.7 for carbon-free LaCoO3. A synergistic effect toward the ORR is observed when carbon is present in the LaCoO3 layer. Carbon is assumed to be more than an additive, enhancing the electronic conductivity of the oxide catalyst. It is suggested that ORRs, catalyzed by the LaCoO3-Super P mixture, are dominated by a 2+2-electron transfer pathway to form the final, hydroxyl ion product.

Myotube differentiation in clustered regularly interspaced short palindromic repeat/Cas9-mediated MyoD knockout quail myoblast cells

  • Kim, Si Won;Lee, Jeong Hyo;Park, Byung-Chul;Park, Tae Sub
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.7
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    • pp.1029-1036
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    • 2017
  • Objective: In the livestock industry, the regulatory mechanisms of muscle proliferation and differentiation can be applied to improve traits such as growth and meat production. We investigated the regulatory pathway of MyoD and its role in muscle differentiation in quail myoblast cells. Methods: The MyoD gene was mutated by the clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 technology and single cell-derived MyoD mutant sublines were identified to investigate the global regulatory mechanism responsible for muscle differentiation. Results: The mutation efficiency was 73.3% in the mixed population, and from this population we were able to establish two QM7 MyoD knockout subline (MyoD KO QM7#4) through single cell pick-up and expansion. In the undifferentiated condition, paired box 7 expression in MyoD KO QM7#4 cells was not significantly different from regular QM7 (rQM7) cells. During differentiation, however, myotube formation was dramatically repressed in MyoD KO QM7#4 cells. Moreover, myogenic differentiation-specific transcripts and proteins were not expressed in MyoD KO QM7#4 cells even after an extended differentiation period. These results indicate that MyoD is critical for muscle differentiation. Furthermore, we analyzed the global regulatory interactions by RNA sequencing during muscle differentiation. Conclusion: With CRISPR/Cas9-mediated genomic editing, single cell-derived sublines with a specific knockout gene can be adapted to various aspects of basic research as well as in functional genomics studies.

Impacts of green technologies in distribution power network

  • Suwanapingkarl, Pasist;Singhasathein, Arnon;Phanthuna, Nattaphong;Boonthienthong, Manat;Srivallop, Kwanchanok;Ketken, Wannipa
    • International Journal of Advanced Culture Technology
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    • v.3 no.1
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    • pp.90-100
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    • 2015
  • Green technologies such as renewable energy resources, Electric Vehicles and Plug-in Hybrid Electric Vehicles (EVs/PHEVs), electric locomotives, etc. are continually increasing at the existing power network especially distribution levels, which are Medium Voltage (MV) and Low Voltage (LV). It can be noted that the increasing level of green technologies is driven by the reduction emission policies of carbon dioxide ($CO_2$). The green technologies can affect the quality of power, and hence its impacts of are analysed. In practical, the environment such as wind, solar irradiation, temperature etc. are uncontrollable, and therefore the output power of renewable energy in that area can be varied. Moreover, the technology of the EVs/PHEVs is still developed in order to improve the performance of supply and driving systems. This means that these developed can cause harmonic distortion as the control system is mostly used power electronics. Therefore, this paper aims to analyse the voltage variation and harmonic distortion in distribution power network in urban area in Europe due to the combination between wind turbine, hydro turbine, photovoltaic (PV) system and EVs/PHEVs. More realistic penetration levels of SSDGs and EVs/PHEVs as forecasted for 2020 is used to analyse. The dynamic load demands are also taken into account. In order to ensure the accurate of simulation results, the practical parameters of distribution system are used and the international standards such as Institute of Electrical and Electronics Engineers (IEEE) standards are also complied. The suggestion solutions are also presented. The MATLAB/Simulink software is chosen as it can support complicate modelling and analysis.