• Title/Summary/Keyword: Source factor

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Psychometric Properties of the Korean Translation of the Attention-Deficit/Hyperactivity Disorder Stigma Questionnaire

  • Rim, Soo Jung;Jang, Hyesue;Park, Subin
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.29 no.3
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    • pp.122-128
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    • 2018
  • Objectives: This study evaluated the psychometric properties of the Korean version of the attention-deficit/hyperactivity disorder (ADHD) Stigma Questionnaire (ASQ) and the effect of the source of information about mental health on ADHD stigma. Methods: The Korean translation of the ASQ was prepared, and 673 participants, 20-64 years of age, completed the questionnaire using an online panel survey in South Korea. The participants also completed questionnaires detailing sociodemographic variables and the source of their mental health knowledge. Cronbach's alpha coefficient was used to explore the internal consistency of the ASQ. Factor analysis using Varimax rotation was conducted to investigate the structure of the ASQ. Results: The 26-item ASQ demonstrated excellent internal consistency (Cronbach's alpha=0.940). Factor analysis supported a three-factor structure, including Concerns with Public Attitudes, Negative Self-Image, and Disclosure Concerns. There were no significant differences in the total ASQ scores according to sociodemographic characteristics. Participants who reported the internet as their major source of information about mental health showed higher ASQ scores compared to those who used other sources for mental health information. Conclusion: The Korean translation of the ASQ has acceptable psychometric properties among Korean adults. Inaccurate information from the internet could increase the stigma toward ADHD.

Estimation of Source Contribution of Particulate Matter in Taegu Area using Factor Analysis (다변량 통계분석법을 이용한 대구지역 부유분진의 오염원 기여도 추정)

  • 최성우;송형도
    • Journal of Environmental Health Sciences
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    • v.26 no.4
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    • pp.1-8
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    • 2000
  • The objective of this study was to identify the sources and to estimate the source contributions to the atmospheric TSP(total suspended particulate matter) and PM-10(particulate matter with aerodynamic diameters less than 10$\mu\textrm{m}$) concentration in Taegu area. A total of 84 samples was collected during the January to December 1999. TSP and PM-10 were collected on filters by portable air sampler, and heavy metals in TSP and PM-배 were analyzed by ICO(Inductively Coupled Plasma Spectrometery) after preliminary treatment. The results were follow as : First, annual average of TSP and PM-10 concentration was 123 and 69$\mu\textrm{g}$/㎥ respectively. The concentration of TSP and PM-10 were highest in winter season compared to other seasons. Second, the concentration of Al, Fe, Mn were higher in TSP than in PM-10, indicating that these heavy metals are generally associate with natural contributions. Third, metal combinations showed that a high correlation among concentrations of heavy metals were follows: As Al, Fe and Mn in TSP ; Ni, Cr, Cd and Pb in PM-10. Finally, Statistical analysis was performed using Principal Components Analysis(PCA) in order to find possible sources of the pollutants. The factor analysis was permitted to identify four major sources(soil/road dust resuspension, waste incineration, furl combustion, vehicular emission) in each fraction. These source accounted for at least 83, 85% of variance of TSP and PM-10 concentration in Taegu area.

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Comparative Study of Coupling Factors for Assessment of Low-Frequency Magnetic Field Exposure

  • Shim, Jae-Hoon;Choi, Min-Soo;Jung, Kyu-Jin;Kwon, Jong-Hwa;Byun, Jin-Kyu
    • Journal of Magnetics
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    • v.21 no.4
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    • pp.516-523
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    • 2016
  • In this paper, coupling factors are calculated based on numerical analysis in order to assess various non-uniform low-frequency magnetic field exposure situations. Two types of non-uniform magnetic field sources are considered; circular coil and parallel wires with balanced currents. For each magnetic field source, source current values are determined so that reference magnetic field magnitude can be measured at the specified point on the human model. Various exposure situations are investigated by changing parameters such as the distance between source and human model, radius of circular coil, and the gap between parallel wires. For equivalent human models, prolate spheroid model and simplified human model from IEC 62311 standard are used. The calculated coupling factor values are compared with those obtained by 2D uniform disk human model, and the dependence of coupling factor on the choice of equivalent human model is analyzed.

KEY IMPACT PARAMETERS FOR APPLICATION OF ALTERNATIVE SOURCE TERM TO KORI UNIT 1

  • Lee, Seung-Chan
    • Nuclear Engineering and Technology
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    • v.42 no.4
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    • pp.394-413
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    • 2010
  • The object of this paper is to identify the key elements that impact a radiation dose at EAB (Exclusion Area Boundary). This study is based on the AST (Alternative Source Terms) as defined in Regulatory Guide 1.183. The LOCA (Loss of Coolant Accident) and the LRA (Locked Rotor Accident) are selected as limiting cases. A sensitivity analysis of accidental behavior with respect to various parameters during LOCA and LRA at Kori Unit 1 is also undertaken for the following objectives: to determine the limiting parameters, to find the impact trend of the radiation dose, and to find the safety margin between AST and TID (Technical Information Document) methodologies. This work confirms that key parameters are particulate removal rate, decontamination factor, iodine chemical form, gap fraction, partitioning factor, and the impact of isotopes group. Comparing TID with AST, the radiation dose of TID is about 80% greater than that of AST under a LOCA, and about 60% greater than that of AST for the case of a LRA; thus the safety margin is remarkably increased when the AST is used. In this work, the sensitivity analysis results are presented in terms of a sensitivity index called the "NDD (Normalized Dose Difference)", which compares the impact of parameters with that of a reference case. These values are derived by using a combination of the leak rate (primary to secondary), iodine chemical form, gap fraction, partitioning factor, spray removal rate, source term, and other variables.

Analysis. Design and Control of Two-Level Voltage Source Converters for HVDC Systems

  • Mohan, D. Madhan;Singh, Bhim;Panigrahi, B.K.
    • Journal of Power Electronics
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    • v.8 no.3
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    • pp.248-258
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    • 2008
  • The Voltage Source Converter (VSC) is replacing the conventional line commutated current source converters in High Voltage DC (HVDC) transmission systems. The control of a two-level voltage source converter and its design dealt with HVDC systems and various factors such as reactive power, power factor, and harmonics distortion are discussed in detail. Simulation results are given for the two-level converter and designed control is used for bidirectional power flow. The harmonics minimization is taken by extending the 6-pulse VSC to multipulse voltage source converters. The control is also tested and simulated for a 12-pulse voltage source converter to minimize the harmonic distortion in AC currents.

Heat source control intelligent system for heat treatment process

  • Lee, JeongHoon;Cho, InHee
    • International journal of advanced smart convergence
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    • v.11 no.4
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    • pp.28-40
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    • 2022
  • Although precise temperature control in the heat treatment process is a key factor in process reliability, there are many cases where there is no separate heat source control optimization system in the field. To solve this problem, the program monitors the temperature data according to the heat source change through sensor communication in a recursive method based on multiple variables that affect the process, and the target heat source value and the actual heat treatment heat source to match the internal air temperature and material temperature. A control optimization system was constructed. Through this study, the error rate between the target temperature and the atmosphere (material surface) temperature of around 10.7% with the existing heat source control method was improved to an improved result of around 0.1% using a process optimization algorithm and system.

Dose Computation Modeling for Frustum Typed Ir-192 of Ralstron Source (Ralstron 선원대체형 Ir-192 원추선원의 선량 전산화 모델링)

  • 최태진
    • Progress in Medical Physics
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    • v.12 no.1
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    • pp.19-29
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    • 2001
  • In dose modeling, the shape of actual source and sealed capsule are important parameter to determine the physical dose computation. The author investigated the effect of filter of source self-absorption and sealed capsule to designed the high dose rate Ir-192 source for Ralstron(Japan) unit. The size of source designed to 1.5 mm $\Phi$ x 1.5mm length of actual source sealed with stainless steel which is 3.0mm $\Phi$ x 12.0mm length connected to driving cable. The dose attenuation was derived 66.3 % from 2655 segmented source at reference point of 10mm lateral distance of source. The output dose rate factor in tissue for designed source showed 0.0013511 cGy/mCi-sec in reference point at 1cm lateral distance of source center. The dose distribution at inferior of source showed the 52% of that of source tip region, however, the filtering effect was small as 4% at 45degrees of source axis. The dose attenuation within 20 degrees of source axis at near source-cable connector showed large filtering effect as 40% over, but the small effect was revealed isotropic dose distribution at large angle.

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Estimation of Source Contribution for Ambient Particulate Matters in Suwon Area (수원지역 입자상 오염물질의 오염원 기여도의 추정)

  • 이태정;김동술
    • Journal of Korean Society for Atmospheric Environment
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    • v.13 no.4
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    • pp.285-296
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    • 1997
  • The suspended particulate matters had been collected on quartz fiber fiters by a cascade impactor having 9 size stages for 4 years (Sep. 1991 to Dec. 1995) in Kyung Hee University-Suwon Campus. Membrane filters were used to collected the particulate matters on each stage. The weight concentration on each stage was obtained by a microbalance and further chemical element levels were determined by an x-ray fluorescence system. Based on these chemical information, our study focused on applying the target transformation factor analysis (TTFA), a receptor model, to identify aerosol sources and to apportion quantitatively their mass contribution. There are total of 63 ambient data sets. Each data set consists of the 8 size-ranged subdata sets characterized by 16 elemental variables. By the results, four to five sources were extracted from each size range and some sources reappeared in other size ranges. Then total of 8 source profiles were statistically generated from all the ranges, such as oil burning source, soil source, field burning source, gasoline related source, coal burning source, marine source, glass related source, and unknown sources. Apportioning aerosol mass to each source was intensively examined by investigating emission inventories near the study area. The results showed that soil particle source was the most significant contributor. However, coal and oil burning sources were the major anthropogenic ones. The study finally proposed some air quality control strategies to achieve the clean air quality in Suwon area.

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A Study on the Evaluation Factor for Success of Port Innovative Cluster Using Kohonen Network (항만혁신클러스터의 성공을 위한 평가요소에 관한 연구)

  • Jang Woon-Jae;Keum Jong-Soo
    • Journal of Navigation and Port Research
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    • v.30 no.1 s.107
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    • pp.45-51
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    • 2006
  • This paper aims to analysis on evaluation factor for success of port innovative cluster. This paper is divided three factors such ac policy, source and operation In addition, three factors are divided into the twelve detail factors. From a total of 30 survey cases, 50 percent randomly selected as the training group and the other 50 percent as the validation group. cases in the training group were used in the development of the Kohonen Network The validation group was used to test the performance of this model. The major findings may be summarized as follows; The prediction accuracy rate is $73.33\%$ The weight of real root and detail factors is calculated by Kohonen Network At the result, success prediction group of port innovative cluster, this paper places the priority on the source factor.

Forecasting the Grid Parity of Solar Photovoltaic Energy Using Two Factor Learning Curve Model (2요인 학습곡선 모형을 이용한 한국의 태양광 발전 그리드패리티 예측)

  • Park, Sung-Joon;Lee, Deok Joo;Kim, Kyung-Taek
    • IE interfaces
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    • v.25 no.4
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    • pp.441-449
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    • 2012
  • Solar PV(photovoltaic) is paid great attention to as a possible renewable energy source to overcome recent global energy crisis. However to be a viable alternative energy source compared with fossil fuel, its market competitiveness should be attained. Grid parity is one of effective measure of market competitiveness of renewable energy. In this paper, we forecast the grid parity timing of solar PV energy in Korea using two factor learning curve model. Two factors considered in the present model are production capacity and technological improvement. As a result, it is forecasted that the grid parity will be achieved in 2019 in Korea.