• Title/Summary/Keyword: Relative dependence

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Statistical Analysis on the Temperature Dependence and Long-Term Change of Relative Humidity Sensors (상대습도계의 온도 의존성과 경년변화의 통계적 분석)

  • Kim, Jong Chul;Choi, Byung Il;Woo, Sangbong;Yang, Inseok
    • Journal of Sensor Science and Technology
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    • v.21 no.6
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    • pp.420-424
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    • 2012
  • We have investigated temperature dependence and long-term change of humidity measurement from 32 relative humidity sensors. The readings of the humidity sensors depended not only the reference humidity, but also temperature of the chamber. Approximately, the temperature dependence of the humidity sensor in average was 0.05 %R.H./$^{\circ}C$ in the temperature range from $5^{\circ}C$ to $55^{\circ}C$. For humidity sensors that have an internal temperature compensation circuit, the resulting temperature dependence was weaker by 20%. It should be also noted that for the humidity sensors used in this work underwent ${\pm}3$ %R.H. change per year for level of confidence of 95%. The users of relative humidity sensors may refer this value as a minimum change when they set the calibration interval of the humidity sensors.

The comparison of angular dependence for optical stimulated luminescence dosimeter(OSLD) and electronic personal dosimeter(EPD) used in Diagnostic Radiology (영상의학과에서 사용되는 광자극 형광선량계와 전자식 개인선량계의 방향 의존성 비교)

  • Kwon, Soon-mu;Park, Jeong-kyu;Kim, Boo-soon
    • Journal of Digital Contents Society
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    • v.16 no.3
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    • pp.463-470
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    • 2015
  • The angular dependence of active dosimeters, EPD, is analysed and compared with that of passive dosimeters, OSLD, after evaluating their relative response and uncertainty of measurement, where it is known that the personal use of them has been increased recently. There appeared a minor variation for average relative response of OSLD in the horizontal and vertical directions within the range $0^{\circ}{\sim}{\pm}90^{\circ}$, which are 0.97 and 0.95 respectively. The variations of angular dependence in the same situations with OSLD are 0.65 and 0.62, respectively, which also reveals a negligible effect on the overall uncertainty. EPDs within the interval $0^{\circ}{\sim}{\pm}60^{\circ}$ for horizontal and vertical directions are 0.94 and 0.97, respectively. These satisfy the requirements of IEC 61526. Uncertainties about the dependence of direction from horizontal and vertical directions are 0.44, 0.40, respectively. The impact of these uncertainties on the overall uncertainty was negligible. However, we observed a significant change in reactivity: the relative reactivities for $+90^{\circ}$ and $-90^{\circ}$ from the horizontal direction are 0.60, 0.37, while that form vertical direction is 0.06. The direction dependence of OSLD was superior to EPD in the range of $0^{\circ}{\sim}{\pm}90^{\circ}$. There appeared a rapidly changing structural features in EPD response for a certain direction. Therefore, we conclude that concurrent use of passive dosimeters and auxiliary dosimeter provides accurate data for personal dose measurements.

The Test of Stochastic Convergence of Environment Emission and Environmental Kuznets Curve Hypothesis in Asian Developing Countries (아시아 국가들 환경오염배출량의 확률수렴성과 환경쿠즈네츠곡선가설 검정)

  • Kim, Ji Uk
    • Environmental and Resource Economics Review
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    • v.19 no.3
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    • pp.571-595
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    • 2010
  • This research applies an panel data stationarity and stochastic convergence test developed by Carrion-i-Silvestre et al. (2005), which has the advantage of considering multiple structural breaks and the presence of cross-section dependence in order to investigate the hypothesis that relative emission $CO_2$ per capita stochastically converge for 11 Asian countries from 1971~2007. We find that relative emission $CO_2$ per capita is stationary after the structural breaks and cross-section dependence are introduced into the model. We also investigate whether Environmental Kuznets Curve (EKC) hypothesis exists in 11 Asian countries. For EKC test, using the panel cointegration tests of Banerjee and Carrion-i-Silvestre (2006) and Westerlund and Edgerton(2007), we find that relative emission $CO_2$ per capita and relative GDP per capita are cointegrated. However EKC hypothesis in 11 Asian countries is not supported.

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Efficient Dynamic Object-Oriented Program Slicing

  • Park, Soon-Hyung;Park, Man-Gon
    • Journal of Korea Multimedia Society
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    • v.6 no.4
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    • pp.736-745
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    • 2003
  • Traditional slicing techniques make slices through dependence graphs. They also improve the accuracy of slices. However, traditional slicing techniques require many vertices and edges in order to express a data communication link because they are based on static slicing techniques. Therefore the graph becomes very complicated, and size of the slices is larger. We propose the representation of a dynamic object-oriented program dependence graph so as to process the slicing of object-oriented programs that is composed of related programs in order to process certain jobs. We also propose an efficient slicing algorithm using the relations of relative tables in order to compute dynamic slices of object-oriented programs. Consequently, the efficiency of the proposed efficient dynamic object-oriented program dependence graph technique is also compared with the dependence graph techniques discussed previously As a result, this is certifying that an efficient dynamic object-oriented program dependence graph is more efficient in comparison with the traditional object-oriented dependence graphs and dynamic object-oriented program dependence graph.

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Evaluation for Performance of a Military Radiation Detecter PDR-1K : Focused on Dependence of Angular and Energy (군사용 방사선 계측기 PDR-1K 반응도 평가 : 방향 및 에너지 의존성을 중심으로)

  • Park, Wonseok;Choi, Junhyuk;Jung, Doyoung;Kim, Jango;Min, Byungin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.2
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    • pp.300-305
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    • 2017
  • In this paper, we performed a evaluation for angular and energy dependence of military radiation detector PDR-1K. Its measuring range is divided into two section, low and high, and each range has a GM tube separately owing to broad scale. We observed a change in relative angular reactivity within 0.928 ~ 1.188 in low range and within 0.743 ~ 1.000 in high range from $-90^{\circ}$ to $+90^{\circ}$. The evaluation for energy dependence appeared a relative reactivity within 0.892 ~ 1.000 above 83 keV. This means PDR-1K isn't possible to use below 83 keV of radiation energy. It is possible to provide response information to user and to increase reliability of radiation measurement through this paper.

An Investigation on the Frequency Dependence of Soil Electrical Parameters

  • Lee, Bok-Hee;Kim, Ki-Bok
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.29 no.4
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    • pp.69-76
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    • 2015
  • This paper presents the results of an investigation into the frequency-dependent electrical parameters for different types of soil as a function of moisture content. The frequency dependence of soil electrical parameters is very important in the design of grounding systems. In fact, the performance of grounding systems is greatly dependent upon various factors such as soil type, particle size, water content, temperature, frequency, and the like. The resistivity and relative permittivity for four different soils were measured and analyzed in the frequency range of 1kHz - 1MHz. Soil resistivity declined as moisture content and frequency increased. In particular, the frequency dependence of soil resistivity was significant as the moisture content was low. In contrast, the relative permittivity of soil dramatically declined at the frequency of 10kHz or below as the moisture content increased, showing the opposite pattern in terms of variation patterns, compared to resistivity.

A Study on the Mass Collection Efficiency in Collector Step of Electrostatic Precipitator by Physical Gas Characterization (전기집진장치에서 가스의 물리적인 특성에 따른 포집구역내의 입자포집율 연구)

  • Ha, Sang-An;Im, Gyeong-Taek;Sin, Nam-Cheol
    • Journal of Environmental Science International
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    • v.7 no.1
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    • pp.36-40
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    • 1998
  • This study was carried out to investigate the collection Efficiency of mass in collector step at the different of physical gas characterization. This work has focused on the dependence of the collection efficiency of mass in the collector zone of a two-stage set up field with gas temperature T and the dew point tmeperature. To identify the dependence of the mass collection efficiency on the Bounded plate of the collector zone MP.k by the spectre electric resistance of dust $p_e$. and the relative humidify ${\varphi}$, 20 at- tempts have been made with three different gas temperature ($50{\circ}C, 80{\circ}C, 110{\circ}C$) at different dew point. At the specific electric resistance of dust $p_e$=$10^6{\Omega}m$ which relative humidity corresponds to $\phi$ > 15%, a easy rise of the sounded plate secluded dust mass share was measured atwain. As the result of the higher cohesion imprisonment power due to the adsorbtion of particle, the rinse of the relative humidity developed on the particle surface. Therefore, the collection efficiency of mass was not predominant the high temperature T in the collector zone, neither was the pecific ellectric resistance of dust dependent.

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Humidity Dependence of the Residual Stress of Diamond-like Carbon Film (습도에 따른 다이아몬드성 카본필름의 잔류응력 변화에 대한 연구)

  • Lee Young-Jin;Kim Tae-Young;Lee Kwang-Ryeol;Yang In-Sang
    • Journal of the Korean Vacuum Society
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    • v.13 no.4
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    • pp.157-163
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    • 2004
  • Dependence of residual compressive stress of diamond-like carbon (DLC) films on relative humidity was investigated. Polymeric, graphitic and diamond-like carbon films were prepared by r.f.-PACVD using methane or benzene with the negative self bias voltage of the substrate ranging from -100 to -800 V. In-situ measurements of the residual stress were carried out in an environment chamber where the relative humidity was varied from 10% to 90%. In dense DLC film of high residual compressive stress and hardness, we could not observe any change in the residual compressive stress with relative humidity. However, in the cases of graphitic and polymeric DLC films, abrupt change in the residual stress occurred by changing the relative humidity. The quantity of the stress change was inversely proportional to the film thickness, which means that the stress change with humidity is not due to the penetration of the water molecule into the film structure, but due to surface interaction between water molecules and film surface.

Alkali Volatilization in TV Screen Glass Melts

  • Kim, Ki-Dong;Hwang, Jong-Hee
    • The Korean Journal of Ceramics
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    • v.6 no.4
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    • pp.343-347
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    • 2000
  • The alkali volatilization of TV screen glass melts with various $K_2$O/R$_2$O mole fraction was investigated by dependence of weight loss on time. The melt conductivity was also determined to evaluate relative alkali diffusion in melts. Based on the results of time dependence and compositional dependence of volatilization combining the results of conductivity, the rate determining process of the volatilization was suggested. From the viewpoint of the production and the application of TV glass it was also discussed a correlation between the dependence of properties on $K_2$O/R$_2$O and the present commercial composition.

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An Empirical Study on the Factors Affecting the Participation of uTrade Hub in terms of Product Characteristics and Sourcing Patterns -Focused on the uTrade Search Services- (제품특성과 구매패턴에 따른 uTradeHub 활용요인 연구)

  • Song, Sun-Yok
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.49
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    • pp.461-490
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    • 2011
  • The purpose of this study is to examine which factors are encouraging SMEs to participate in uTradeHub(focused on the uTrade search service) in terms of product characteristics and sourcing patterns. The three factors encouraging Trade e-Marketplaces are identified in this study. First, internal factors include the support of top management, mature of IT infrastructure. Second, external factors include the pressure of industry, industry competition, dependence of trading partners. Third perception factors are perceived Usefulness, perceived easy of use. The empirical analysis had the following results. First, it reveals that support of top management, mature of IT infrastructure, industry competition have significant influence upon uTrade Search Services. On the other hand, pressure of industry, dependence of trading partners, Perceived relative benefits are not significant variable of the participation in uTrade Search Services. Second, the factors affecting the participation in uTrade Search Services are differentiated in terms of product characteristics and sourcing patterns. And the support of top management, mature of IT infrastructure, Perceived relative benefits are emphasized very important factors affecting the participation of uTrade Search Services in SMEs. The industry competition is recognized as more important factor in horizontal market in which Spot sourcing just like Operating products is trading. On the other hands, the dependence of trading partners are significant factor in vertical market in which Systemic sourcing just like Manufacturing products is trading.

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