• Title/Summary/Keyword: stable current

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An Analysis of the Spatial Range of Environmental Impact Assessment(EIA) - Focusing on Landscape Ecological Aspects - (환경영향평가대상의 공간적 평가범위 설정에 관한 연구 - 경관생태학적 측면에서 -)

  • Oh, Kyushik;Kim, Hee-Ju;Lee, Dong-Kun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.12 no.3
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    • pp.130-141
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    • 2009
  • The spatial range of EIA is mainly related to landscape ecological factors such as topography, geology, animals, and plants. Problems were detected involved land, soil, noise, oscillation, the atmosphere, animals, and plants in the natural-environment. First of all, the current EIA lacks explicit spatial ranges and sections in terms of scientific exactitude and objectivity for assessment. Secondly, there are overlapping influence-area problems resulting in cumulative impacts of unit developments that accumulate. Finally, some developments have no regard for ecological and conservational value in relation to determining which effect ecological stability, and which should be regarded as Regional Ecological Resources. Therefore, this study suggests that EIA should be improved in the following manner. First, the standard classification of landscape unit for analysis should be established 10 regulate each spatial range on a wide-landscape scale. Secondly, the impacts resulting from the interaction of overlapping influence-area developments between individual development should be assessed. Third, Minimization of the of the environmental effects is needed by applying the cumulative effects to the influence-area where developments occur in the same time or in a sequence. Fourth, individual characteristics of landscape elements such as roads, rivers, and green networks need to be considered separately in the analysis. Finally, regional ecological habitats should be included in the analysis in order to achieve stable ecosystems.

Genetic and Biochemical Characterization of the Biphenyl Dioxygenase from Pseudomonas sp. Strain B4

  • Rodarie, David;Jouanneau, Yves
    • Journal of Microbiology and Biotechnology
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    • v.11 no.5
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    • pp.763-771
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    • 2001
  • Biphenyl dioxygenase (BPDO), which catalyzes the first step in the bacterial degradation of biphenyl and polychlorinated biphenyls, was characterized in Pseudomonas sp. B4. The bphA locus containing the four structural genes encoding BPDO were cloned and sequenced. A regulatory gene as well as a putative regulatory sequence were identified upstream of this locus. A transposase-like gene was found within a 1-kb region further upstream, thereby suggesting that the bphA locus may be carried on a transposable element. The three components of the BPDO enzyme have been separately overexpressed and purified from E. coli. The ferredoxin and terminal dioxygenase components showed biochemical properties comparable to those of two previously characterized BPDOs, whereas the ferredoxin reductase exhibited an unusually high lability. The substrate selectivity of BPDO was examined in vivo using resting cell assays performed with mixtures of selected polychlorinated biphenyls. The results indicated that para-substituted congeners were the preferred substrates. In vitro studies were carried out on a BPDO complex where the reductase from strain B4 we replaced by the more stable isoform from Comamonas testosteroni B-356. The BPDO enzyme had a specific activity of $0.26{\pm}0.02 {\mu}mol {min^-1}{mg^-1}\;of\;ISP_{BPH}$ with biphenyl as the substrate. The 2,3-, 4,4'-, and 2,4,4'-chlorobiphenyls were converted to single dihydrodiols, while 2,4'-dichlorobiphenyl gave rise to two dihydrodiols. The current data also indicated that 2,4,4'-trichlorobiphenyl was a better substrate than the 4,4'-dichlorinated congener.

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A Study on the Institutional Improvement for the Employment Stability of Foreign Workers in the Construction Industry (건설업의 외국인 근로자 고용안정을 위한 제도적 개선방안 도출 연구)

  • Cho, Jae-Hwan
    • Journal of the Society of Disaster Information
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    • v.15 no.4
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    • pp.514-523
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    • 2019
  • Purpose: This study was designed to provide necessary institutional improvements for job security for foreign workers in the domestic construction sector. Method: I analyzed the National Statistical Office and related reports to investigate the status of foreign workers. Based on this, the government came up with measures to improve the system. Results: Based on the current comparative advantage index (RCA) analysis, the technology standard of foreign workers compared to Korean workers was evaluated, and the results were analyzed in order of moldwork, rebar, concrete work, stone work, and waterproof work. Conclusion: A foreign worker's work system was introduced to solve the problem of local Lunar New Year's Day field manpower. To ensure stable implementation of the system, there is a need to improve the operation of the employment permit system at construction sites and limit the size of the construction industry that introduces the employment permit system.

Optimization of Operating Parameters and Components for Water Electrolysis Using Anion Exchange Membrane (음이온 교환막 알칼리 수전해를 위한 운전 조건 및 구성요소의 최적화)

  • Jang, Myeong Je;Won, Mi So;Lee, Kyu Hwan;Choi, Sung Mook
    • Journal of the Korean institute of surface engineering
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    • v.49 no.2
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    • pp.159-165
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    • 2016
  • The hydrogen has been recognized as a clean, nonpolluting and unlimited energy source that can solve fossil fuel depletion and environmental pollution problems at the same time. Water electrolysis has been the most attractive technology in a way to produce hydrogen because it does not emit any pollutants compared to other method such as natural gas steam reforming and coal gasification etc. In order to improve efficiency and durability of the water electrolysis, comprehensive studies for highly active and stable electrocatalysts have been performed. The platinum group metal (PGM; Pt, Ru, Pd, Rh, etc.) electrocatalysts indicated a higher activity and stability compared with other transition metals in harsh condition such as acid solution. It is necessary to develop inexpensive non-noble metal catalysts such as transition metal oxides because the PGM catalysts is expensive materials with insufficient it's reserves. The optimization of operating parameter and the components is also important factor to develop an efficient water electrolysis cell. In this study, we optimized the operating parameter and components such as the type of AEM and density of gas diffusion layer (GDL) and the temperature/concentration of the electrolyte solution for the anion exchange membrane water electrolysis cell (AEMWEC) with the transition metal oxide alloy anode and cathode electrocatalysts. The maximum current density was $345.8mA/cm^2$ with parameter and component optimization.

Improvement of Degradation Characteristics in a Large, Racetrack-shaped 2G HTS Coil for MW-class Rotating Machines

  • Park, Heui Joo;Kim, Yeong-chun;Moon, Heejong;Park, Minwon;Yu, Inkeun
    • Journal of Electrical Engineering and Technology
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    • v.13 no.3
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    • pp.1166-1172
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    • 2018
  • Degradation due to delamination occurs frequently in the high temperature superconductors (HTS) coil of rotating machines made with 2nd generation (2G) HTS wire, and the authors have observed other similar cases. Since an HTS field coil for a rotating machine is required to have stable current control and maintain a steady state, co-winding techniques for insulation material and epoxy resin for shape retention and heat transfer improvement are applied during coil fabrication. However, the most important limiting factor of this technique is delamination, which is known to be caused by the difference in thermal expansion between the epoxy resin and 2G HTS wire. Therefore, in this study, the experimental results of mixing the ratio of epoxy resin and alumina ($Al_2O3$) filler were applied to the fabrication of small and large test coils to solve the problem of degradation. For the verification of this scheme, eight prototypes of single pancake coils with different shapes were fabricated. They showed good results. The energization and operation maintenance tests of the stacked coils were carried out under liquid neon conditions similar to the operation temperature of an MW-class rotating machine. In conclusion, it was confirmed that the alumina powder mixed with epoxy resin in an appropriate ratio is an effective solution of de-lamination problem of 2G HTS coil.

Design of Network-Based Induction Motors Fault Diagnosis System Using Redundant DSP Microcontroller with Integrated CAN Module (DSP 마이크로컨트롤러를 사용한 CAN 네트워크 기반 유도전동기고장진단 시스템 설계)

  • Yoon, Chung-Sup;Hong, Won-Pyo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.19 no.5
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    • pp.80-86
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    • 2005
  • Induction motors are a critical component of many industrial processes and are frequently integrated in commercially available equipment. Safety, reliability, efficiency, and performance are some of the major concerns of induction motor applications. Fault tolerant control (FTC) strives to make the system stable and retain acceptable performance under the system faults. All present FTC method can be classified into two groups. The first group is based on fault detection and diagnostics (FDD). The second group is includes of FDD and includes methods such as integrity control, reliable stabilization and simultaneous stabilization. This paper presents the fundamental FDD-based FTC methods, which are capable of on-line detection and diagnose of the induction motors. Therefore, our group has developed the embedded distributed fault tolerant and fault diagnosis system for industrial motor. This paper presents its architecture. These mechanisms are based on two 32-bit DSPs and each TMS320F2407 DSP module processes the stator current, voltage, temperatures, vibration signal of the motor.

A Research of Design and Implementation of Visual Program to Displaying External Factors of Marine Buoy using Quest3D (Quest3D 기반 해상부표 동적안정성의 시각적 표현 프로그램 설계 및 구현에 관한 연구)

  • Lee, Seo-Jeong;Lee, Jae-Wook;Gug, Seung-Gi
    • Journal of Navigation and Port Research
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    • v.36 no.8
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    • pp.599-605
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    • 2012
  • As vessels are faster and bigger, higher safety navigation techniques have been required. In marine traffic area, buoy is to be one of the most important equipment, so that it should be built stable and robust. Verification in design level is good to accomplish it. This paper tries to implement visual program to confirm the external stability, which shows the movement on water by external factors such as wind, tide and current. Considering further requirements for additional influences or functions, design architecture for program introduces the concept of software component. Using Quest3D as the graphic tool, visual programming with software component concept can be implemented.

A Classification of lschemic Heart Disease using Neural Network in Magnetocardiogram (심자도에서 신경회로망을 이용한 허혈성 심장질환 분류)

  • Eum, Sang-hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.11
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    • pp.2137-2142
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    • 2016
  • The electrical current generated by heart creates not only electric potential but also a magnetic field. In this study, the signals obtained magnetocardiogram(MCG) using 61 channel superconducting quantum interference device(SQUID) system, and the clinical significance of various feature parameters has been developed MCG. Neural network algorithm was used to perform the classification of ischemic heart disease. The MCG signal was obtained to facilitate the extraction of parameters through a process of pre-processing. The data used to research the normal group 10 and ischemic heart disease group 10 with visible signs of stable angina patients. The available clinical indicators were extracted by characteristic point, characteristic interval parameter, and amplitude ratio parameter. The extracted parameters are determined to analysis the significance and clinical parameters were defined. It is possible to classify ischemic heart disease using the MCG feature parameters as a neural network input.

Video Stabilization using Phase Correlation and Kalman Filter-Based Motion Prediction (위상상관과 칼만 필터 움직임 예측을 이용한 동영상 안정화)

  • Han, Hag-Yong;Jeong, Hyo-Won;Kang, Bong-Soon;Hur, Kang-In
    • Journal of the Institute of Convergence Signal Processing
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    • v.10 no.2
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    • pp.106-111
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    • 2009
  • Real-time video stabilization technology is used in correction for the camera vibrations of the hand-held camera by hand or fixed camera by external condition. This paper is about the counterplan to cope with the vibration of the movie generated by the large external cause relatively. we use the movie stabilization parameters with the phase correlation method based the DFT to get the displacements of the current frame to the reference frame. we use the kalman filter for the efficient and stable searching works on the phase correlation map and present the proper conditions for the real-time processing through the experiments. We propose the measure to evaluate the capability of the video stabilizer which is the standard deviation of the brightness of the center block. and compare the capability for the video sequences randomly shifted and the jittered video sequences obtained from camera.

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Electrical Properties by Effect of Metal Complex of G4-48PyP Dendritic Macromolcules Thin Films (G4-48PyP 덴드리틱 거대분자 박막의 금속이온 착체에 의한 전기적 특성)

  • Son, J.H.;Jung, S.B.;Kim, B.S.;Park, T.C.;Kwon, Y.S.
    • Proceedings of the KIEE Conference
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    • 2002.11a
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    • pp.16-18
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    • 2002
  • We attempted to fabricate a dendrimer Langmuir-Blodgett(LB) films containing 48 pyridinepropanol functional end group. As the pyridinepropanol functional group could form a complex structure with metal ions. In this study the samples for electrical measurement were fabricated to two types metal complexes with $Pt^{4+}$ and $Fe^{2+}$ ions by LB method. And we have investigated the surface activity at the air-water interface as well as the electrical properties for the monolayers of pure G4-48PyP dendrimer and its complex with metal ions($Pt^{4+}$ and $Fe^{2+}$ ions). In the surface pressure-area($\pi-A$) isotherms of the dendrimers, the stable condensed films formed at the air-water interface and the metal ions effect showed the difference on molecular behavior. We have studied the electrical properties of the ultra thin dendrimer LB films investigated by the current-voltage(I-V) characteristics of metal/dendrimer LB films/metal(MIM) structure. In conclusion, it is demonstrated that the metal ion around G4-48PyP dendrimer can contribute to make formation of network structure among dendrimers and it result from the change of electrical properties.

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