• Title/Summary/Keyword: named source

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Types of Place Names According to the Named Sources and Those Cultural-Political Meanings (명명 유연성에 따른 지명 유형과 문화정치적 의의)

  • Kim, Sun-Bae
    • Journal of the Korean association of regional geographers
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    • v.17 no.3
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    • pp.270-296
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    • 2011
  • The named source kept in all place names alludes to the close relationship between place name and its place while it also becomes a fundamental condition for geographical research on place names. Meanwhile, the named source may be recognized differently according to who the social subjects producing and changing place names Life. Place names represent and constitute the identity and the ideology of the diverse social subjects. This aspect is related to cultural politics concerned with conflicts and contestation among different social subjects over the meaning of place names. Particularly, the Gongju-Mok Jingwan Area in the Korean peninsula has long history and geopolitical location as a borderland and a buffer zone. As a result, it has provided many conditions for cultural diversity and power relations, both of which have caused social subjects to contest their social power across space and time, and has led to produce the several types in the changes of place names. Therefore, this paper aims to investigate the types according to the named source, especially that of the forepart of place names morpheme, and those cultural-political meanings. These place names are classified into three large groups, such as the physical place names, the social place names, and the economic place names. These types of place names have represented the place identity and the ideology of diverse social subjects, and also accompanied the changes by power relations between themselves.

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Source Enumeration Method using Eigenvalue Gap Ratio and Performance Comparison in Rayleigh Fading (Eigenvalue Gap의 Ratio를 이용한 신호 개수 추정 방법 및 Rayleigh Fading 환경에서의 신호 개수 추정 성능 비교)

  • Kim, Taeyoung;Lee, Yunseong;Park, Chanhong;Choi, Yeongyoon;Kim, Kiseon;Lee, Dongkeun;Lee, Myung-Sik;Kang, Hyunjin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.24 no.5
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    • pp.492-502
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    • 2021
  • In electronic warfare, source enumeration and direction-of-arrival estimation are important. The source enumeration method based on eigenvalues of covariance matrix from received is one of the most used methods. However, there are some drawbacks such as accuracy less than 100 % at high SNR, poor performance at low SNR and reduction of maximum number of estimating sources. We suggested new method based on eigenvalues gaps, which is named AREG(Accumulated Ratio of Eigenvalues Gaps). Meanwhile, FGML(Fast Gridless Maximum Likelihood) which reconstructs the covariance matrix was suggested by Wu et al., and it improves performance of the existing source enumeration methods without modification of algorithms. In this paper, first, we combine AREG with FGML to improve the performance. Second, we compare the performance of source enumeration and direction-of-arrival estimation methods in Rayleigh fading. Third, we suggest new method named REG(Ratio of Eigenvalues Gaps) to reduce performance degradation in Rayleigh Fading environment of AREG.

A Study on the Environmental Professionals′ Risk Perception towards Some Pollution Issues (일부 환경 전문가들의 환경 위해성 인식도에 관한 연구)

  • 신동천;박종연;임영욱;김진용;장은아;박성은
    • Environmental Analysis Health and Toxicology
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    • v.14 no.4
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    • pp.175-187
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    • 1999
  • To investigate the risk perception of environmental issues, two consequtive surveys were conducted to environmental professionals using a standardized questionnaire from September to October in 1999. The number of subjects were 72 for the first survey and 68 for the second one. The questionnaire was consisted of items such as the degree of environmental pollution in Korea, risk perception of some issues on human health and ecosystem, and seriousness of the problems in the real situation in Korea. For the degree of environmental pollution in Korea, the average risk rating in the second test (7.4 point) was significantly higher than that in the first test (7.2 point). The risk perception on the general human health and ecosystem, and the seriousness in Korea situation were analyzed in the order of ′air pollution′, ′water pollution′,′soil contamination′,′waste′,′toxic chemical pollutants′,′food contamination′,′ocean contamination′, ′odor pollution′, and ′noise pollution′. Also ′toxic chemical pollutants′ problem was perceived to be the highest risk on general human health or ecosystem, and on present situation in Korea. ′Automotive vehicle exhaust′ problem was perceived to be the most severe environmental problems among specific 30 items. ′Industrial source air pollution′,′toxic air pollutants′, and ′domestic and industrial source pollutants to surface water′ were relatively severe environmental problems comparing to other problems. The pollution issues were classified into four categories by two aspects of perception; risk in general setting and seriousness in Korea situation. If the issues were highly serious in Korea and low risk perception in general setting then it is named "the Korea-specific group". Those that were all high score in two aspects, named "the Common group". Those that were all low in two aspects, named "the Nonsignificant group". And the issues were high risk perception in general setting and low seriousness in Korean situation, named "the Latent group".

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A spent nuclear fuel source term calculation code BESNA with a new modified predictor-corrector scheme

  • Duy Long Ta ;Ser Gi Hong ;Dae Sik Yook
    • Nuclear Engineering and Technology
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    • v.54 no.12
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    • pp.4722-4730
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    • 2022
  • This paper introduces a new point depletion-based source term calculation code named BESNA (Bateman Equation Solver for Nuclear Applications), which is aimed to estimate nuclide inventories and source terms from spent nuclear fuels. The BESNA code employs a new modified CE/CM (Constant Extrapolation - Constant Midpoint) predictor-corrector scheme in depletion calculations for improving computational efficiency. In this modified CE/CM scheme, the decay components leading to the large norm of the depletion matrix are excluded in the corrector, and hence the corrector calculation involves only the reaction components, which can be efficiently solved with the Talyor Expansion Method (TEM). The numerical test shows that the new scheme substantially reduces computing time without loss of accuracy in comparison with the conventional scheme using CRAM (Chebyshev Rational Approximation Method), especially when the substep calculations are applied. The depletion calculation and source term estimation capability of BESNA are verified and validated through several problems, where results from BESNA are compared with those calculated by other codes as well as measured data. The analysis results show the computational efficiency of the new modified scheme and the reliability of BESNA in both isotopic predictions and source term estimations.

Modified Capacitor-Assisted Z-Source Inverter Topology with Enhanced Boost Ability

  • Ho, Anh-Vu;Chun, Tae-Won
    • Journal of Power Electronics
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    • v.17 no.5
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    • pp.1195-1202
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    • 2017
  • This paper presents a novel topology named a modified capacitor-assisted Z-source inverter (MCA-ZSI) based on the traditional ZSI. The impedance network of the proposed MCA-ZSI consists of two symmetrical cells coupled with two capacitors with an X-shape structure, and each cell has two inductors, two capacitors, and one diode. Compared with other topologies based on switched ZSI with the same number of components used at impedance network, the proposed topology provides higher boost ability, lower voltage stress across inverter switching devices, and lower capacitor voltage stress. The improved performances of the proposed topology are demonstrated in the simulation and experimental results.

The Real -Time Dispersion Modeling System

  • Koo, Youn-Seo
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.E4
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    • pp.215-221
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    • 2002
  • The real-time modeling system, named AirWatch System, has been developed to evaluate the environmental impact from a large source. It consists of stack TMS (TeleMetering System) that measures the emission data from the source, AWS (Automatic Weather Station) that monitors the weather data and computer system with the dispersion modeling software. The modeling theories used in the system are Gaussian plume and puff models. The Gaussian plume model is used for the dispersion in the simple terrain with a point meteorological data while the puff model is for the dispersion in complex terrain with three dimensional wind fields. The AirWatch System predicts the impact of the emitted pollutants from the large source on the near-by environment on the real -time base and the alarm is issued to control the emission rate if the calculated concentrations exceed the modeling significance level.

Study of Back-Up Electric Power Source as a Role for Instant Power Industry Safety by Super Capacitor (순간 정전시 산업안전용 보조전원 역할의 Super Capacitor에 관한 연구)

  • 김상길;김종철;허진우;김경민;이용욱;강안수
    • Proceedings of the Safety Management and Science Conference
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    • 1999.11a
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    • pp.345-354
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    • 1999
  • A new type of capacitor named "Super Capacitor" has been developed, in which the properties of electric double layer formed at the interface of activated carbon electrode- liquid organic electrolyte is applied. This capacitor is small In size, light in weight, wide In temperature range(-25~$70^{\circ}C$), large in charge-discharge capability and good in voltage preservation. And this super capacitor is applied as a power back-up for electricity failure in volatile memory devices etc., a power source for a short time and a power source for operating actuators. At present the development of high power back-up types of the capacitor system and improvement of their characteristics are being actively conducted in order to find wider applications.lications.

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Numerical studies on the important fission products for estimating the source term during a severe accident

  • Lee, Yoonhee;Cho, Yong Jin;Lim, Kukhee
    • Nuclear Engineering and Technology
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    • v.54 no.7
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    • pp.2690-2701
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    • 2022
  • In this paper, we select important fission products for the estimation of the source term during a severe accident of a PWR. The selection is based on the numerical results obtained from depletion calculations for the typical PWR fuel via the in-house code named DEGETION (Depletion, Generation, and Transmutation of Isotopes on Nuclear Application), release fractions of the fission products derived from NUREG-1465, and effective dose conversion coefficients from ICRP 119. Then, for the selected fission products, we obtain the adjoint solutions of the Bateman equations for radioactive decay in order to determine the importance of precursors producing the aforementioned fission products via radioactive decay, which would provide insights into the assumption used in MACCS 2 for a level 3 PSA analysis in which up to six precursors are considered in the calculations of radioactive decays for the fission product after release from the reactor.

Development of a magnetic field calculation program for air-core solenoids which can control the precision of a magnetic field

  • Huang, Li;Lee, Sangjin
    • Progress in Superconductivity and Cryogenics
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    • v.16 no.4
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    • pp.53-56
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    • 2014
  • A numerical method of magnetic field calculation for the air-core solenoid is presented in this paper. In application of the Biot-Savart law, the magnetic field induced from the source current can be obtained by a double integration ormula. The numerical method named composite Simpson's rule for the integration is applied to the program and the adaptive quadrature method is used to adjust the step size in the calculation according to the precision we need. When the target point is in the solenoid and the intergrand's denominator may be zeroin the process of calculation, the method sill can provide an appropriate result. We have developed a program which calculates the magnetic field with at least 1ppm precision and named it as rzBI() to implement this method. The method has been used in the design of an MRI magnet, and the result show it is very flexible and convenient.

2,4-D Biodegradation Using Microorganism Extracted From Soil (1) (토양미생물에 의한 2, 4-D 분해에 관한 연구 (1))

  • Choung, Youn-kyoo;Lee, Byung chan;Kim, Jin-wook
    • Journal of Korean Society of Water and Wastewater
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    • v.13 no.4
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    • pp.45-53
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    • 1999
  • The microbial organisms named "Pseudomonas sp. LK-14" were isolated from farm land and shallow river sediment, activated, augmented and identified; which were using 2,4-D (2,4-Dichlorophenoxyacetic acid) as a sole carbon source and energy source. 2,4-D removal efficiency of LK-14 with 2,4-D sole carbon source (reactor S) were higher than that of Activated Sludge with 2,4-D sole carbon source (reactor A). Dynamic bioligical reaction kinetic parameters (sole carbon source was 2,4-D) obtained from batch reactor experiments were ${\mu}_{max}$ $0.105hr^{-1}$, $K_{s,24D}$ 15.64mg/L, $K_{i,24D}$ $1.94h^{r-1}$, $Y_{24D}$ 0.39 for LK-14 and ${\mu}_{max}$ $0.008hr^{-1}$, $K_{s,24D}$ 26.95mg/L, $K_{i,24D}$ $1.75hr^{-1}$, $Y_{24D}$ 0.10 for Activated Sludge. Using these parameters, we could predict the behaviors of 2,4-D substrate utilized by LK-14 and Activated Sludge in batch reactors. The kinetic parameters are enable to predict the 2,4-D substrate and microbial population behavior entering into wastewater treatment plants by using unsteady states dynamic simulation modeling technique.

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