• Title/Summary/Keyword: Mass source

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A study on the relationship between fashion consumption style and the related variables of male and female consumers (남녀대학생의 패션소비유형과 관련변인의 관계연구)

  • Ha, Jong-Kyung
    • Korean Journal of Human Ecology
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    • v.17 no.3
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    • pp.485-492
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    • 2008
  • The study is to provide the types of fashion consumption of male and female university students and to analyze fashion involvement to the types and students' source of fashion information. Then the correlations were examined between fashion involvement and source of fashion information. The data were analyzed by a factor analysis, one-way ANOVA, Duncan test, cluster analysis, cross-tabulation analysis. The results are as follows: 1. The awareness about fashion consumption is classified into five factors: "hedonic consumption", "impulsive consumption", "brand loyal consumption", "prudent consumption", and "independent consumption". The fashion involvement to the types is categorized into four factors; "pleasure", "trend", "image", and "risk awareness". The source of fashion information is categorized into "mass media", "product information", and "personal information". 2. The fashion consumption is classified into three types: "an independent consumer type", "a brand loyal/ prudent consumer type", and "an impulsive consumer type". 3. In the fashion involvement to the types and the source of fashion information, there is a high correlation between the factors of "mass media" and "trend", "product information" and "pleasure" and "personal information" and "trend".

Derivation of Photon Energy Fluence and Mass Energy Absorption Coefficient for 1 Gy Absorbed Dose of Water in Brachytherapy using Ir192 Source (Ir192 선원을 이용한 근접치료에서 물 흡수선량 1 Gy에 대한 광자에너지 플루언스와 질량에너지흡수계수 유도)

  • Kim, Jong-Eon;Ahn, Il-Hoon
    • Journal of the Korean Society of Radiology
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    • v.16 no.1
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    • pp.61-66
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    • 2022
  • The purpose of this study is to derive photon energy fluence and mass energy absorption coefficient for 1 Gy of absorbed dose of water in brachytherapy using an Ir192 source. From the radiotherapy physics written by Khan, the half-value of lead for the gamma ray beam of the Ir192 source was obtained. The linear attenuation coefficient and the mass attenuation coefficient were calculated from the obtained half-value layer of lead. By matching the calculated lead mass attenuation coefficient with the NIST mass attenuation coefficient data, the photon energy of the matching mass attenuation coefficient was determined as the effective energy. By matching the determined effective energy with the photon energy of the NIST data on the mass energy absorption coefficient of water, the mass energy absorption coefficient of water was obtained as 0.03273 cm2/g(32.73 cm2/kg). The photon energy fluence was calculated as 0.03055 J/cm2 by dividing the obtained mass energy absorption coefficient (32.73 cm2/kg) by the absorbed dose of water 1 Gy.

Natural Convection Heat Transfer in a Hemispherical Pool with Volumetric Heat Sources (체적 열원이 내재된 반구에서의 자연대류 열전달)

  • Park, Hae-Kyun;Chung, Bum-Jin
    • Journal of Energy Engineering
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    • v.24 no.3
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    • pp.135-141
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    • 2015
  • The core melts stratifies into lower mixture layer and upper metal layer by density in a severe accident condition. The decay heat generated from the mixture layer threatens the integrity of the reactor vessel. This study simulated the natural convection heat transfer of the mixture layer with volumetric heat source using the mass transfer system. $H_2SO_4-CuSO_4$ electroplating system was used as the mass transfer system. With the modified Rayleigh number of $3{\times}10^{14}$, the Nusselt number showed minimum at the bottom and increased along curvature to the top of the experimental apparatus.

Analysis of Organic Molecular Markers in Atmospheric Fine Particulate Matter: Understanding the Impact of "Unknown" Point Sources on Chemical Mass Balance Models

  • Bae, Min-Suk;Schauer, James J.
    • Journal of Korean Society for Atmospheric Environment
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    • v.25 no.3
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    • pp.219-236
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    • 2009
  • Particle-phase organic tracers (molecular markers) have been shown to be an effective method to assess and quantify the impact of sources of carbonaceous aerosols. These molecular markers have been used in chemical mass balance (CMB) models to apportion primary sources of organic aerosols in regions where the major organic aerosol source categories have been identified. As in the case of all CMB models, all important sources of the tracer compounds must be included in a Molecular Marker CMB (MM-CMB) model or the MMCMB model can be subject to biases. To this end, the application of the MM-CMB models to locations where reasonably accurate emissions inventory of organic aerosols are not available, should be performed with extreme caution. Of great concern is the potential presence of industrial point sources that emit carbonaceous aerosols and have not been well characterized or inventoried. The current study demonstrates that emissions from industrial point sources in the St. Louis, Missouri area can greatly bias molecular marker CMB models if their emissions are not correctly addressed. At a sampling site in the greater St. Louis Area, carbonaceous aerosols from industrial point sources were found to be important source of carbonaceous aerosols during specific time periods in addition to common urban sources (i.e. mobile sources, wood burning, and road dust). Since source profiles for these industrial sources have not been properly characterized, method to identify time periods when point sources are impacting a sampling site, needs to avoid obtaining biases source apportionment results. The use of real time air pollution measurements, along with molecular marker measurements, as a screening tool to identify when point sources are impacting a receptor site is presented.

Mathematical Models on Diffusive Loss of Non-Aqueous Phase Organic Solvents from a Disk Source (디스크소스로부터 NAPL의 확산손실에 관한 수학적 모델)

  • Yoon, In-Taek;S.E., Dickson
    • Journal of Soil and Groundwater Environment
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    • v.13 no.6
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    • pp.40-49
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    • 2008
  • Matrix diffusion from planar fractures was studied mathematically and through physical model experiments. Mathematical models were developed to simulate diffusion from 2D and 3D instantaneous disk sources and a 3D continuous disk source. The models were based on analytical solutions previously developed by Carslaw and Jaeger (1959). The mathematical simulations indicated that the 2D scenario produces significantly different results from the 3D scenario, the time for mass disappearance is significantly larger for continuous sources than for instantaneous sources, the normalized concentration generally decreased over time for instantaneous sources while it increased over time for continuous sources, diffusion rates decrease significantly over time and space, and the normalized mass loss from the source zone never reaches 1 for continuous sources due to the semi-infinite integral. The simulations also showed that disappearance times increase exponentially with increasing source radii and matrix porosity, and decrease with increasing aqueous-phase NAPL solubilities.

The design and fabricationt for ion fraction measurement of plasma generator (플라즈마발생기의 이온분율 측정 장치 설계 및 제작)

  • Lee, Chan-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.368-368
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    • 2008
  • Ion implantation has been widely developed during the past decades to become a standard industrial tool. To comply with the growing needs in ion implantation, innovative technology for the control of ion beam parameters is required. Beam current, beam profile, ion fractions are of great interest when uniformity of the implant is an issue. Especially, it is important to measure the spatial distribution of beam power and also the energy distribution of accelerated ions. This energy distribution is influenced by the proportion of mass for ion in the plasma generator(ion source) and by charge exchange and dissociation within the accelerator structure and also by possible collective effects in the neutralizer which may affect the energy and divergence of ions. Hydrogen atom has been the object of a good study to investigate the energy distribution. Hydrogen ion sources typically produce multi-momentum beams consisting of atomic ion ($H^+$) and molecular ion ($H_2^+$ and $H_3^+$). In the beam injector, the molecular ions pass through a charge-exchanges gas cell and break up into atomic with one-half (from $H_2^+$) or one-third (from $H_3^+$) according to their accelerated energy. Burrell et al. have observed the Doppler shifted lines from incident $H^+$, $H_2^+$, and $H_3^+$ using a Doppler shift spectroscopy. Several authors have measured the proportion of mass for hydrogen ion and deuterium using an ion source equipped with a magnetic dipole filter. We developed an ion implanter with 50-KeV and 20-mA ion source and 100-keV accelerator tube, aiming at commercial uses. In order to measure the proportion of mass for ions, we designed a filter system which can be used to measure the ion fraction in any type of ion source. The hydrogen and helium ion species compositions are used a filter system with the two magnets configurations.

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DETECTION OF WIDE PLANETARY SYSTEM WITH MICROLENSING

  • Ryu, Yoon-Hyun;Park, Myeong-Gu;Chang, Heon-Young;Lee, Ki-Won
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.108.2-108.2
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    • 2012
  • Recent results from microlensing surveys show that a free-floating planet or a wide-separation planet is more numerous than a main-sequence star in the Galaxy. Moreover, the detection efficiency of the planets will be improved in next-generation experiments with a high survey monitoring frequency. However, microlensing events produced by both planets appear similar light curves with a short duration timescale, thus it is difficult to distinguish them. In this paper, we investigated the detectable separation range of a wide-separation planet as the planet bound to its host star. We construct the fractional deviation maps using the magnifications of the planetary lensing and the single-lensing by planet itself for various parameters such as a mass ratio, separation, and source radius. As a result, we found that the pattern of the fractional deviation is related to the ratio of source radius to caustic size, and the ratio satisfying the detection criterion (i.e., ${\geq}5%$ in the fractional deviation) varies with a separation. Hence, we derived a fitting formula as the function of a mass ratio and a source radius to reflect the variation in the calculations of the detectable separation range of a wide-separation planet as the planet bound to its host star. In addition, we estimated the condition that a wide-separation planet can be detected as a single-lensing event under the finite source effect. We found that such a case is possible provided that the source radius is smaller than ~2.5 times of Einstein ring radius of a planet, regardless of a separation or a mass ratio.

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Quantitative Evaluation of Radiation Dose Rates for Depleted Uranium in PRIDE Facility

  • Cho, Il Je;Sim, Jee Hyung;Kim, Yong Soo
    • Journal of Radiation Protection and Research
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    • v.41 no.4
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    • pp.378-383
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    • 2016
  • Background: Radiation dose rates in PRIDE facility is evaluated quantitatively for assessing radiation safety of workers because of large amounts of depleted uranium being handled in PRIDE facility. Even if direct radiation from depleted uranium is very low and will not expose a worker to significant amounts of external radiation. Materials and Methods: ORIGEN-ARP code was used for calculating the neutron and gamma source term being generated from depleted uranium (DU), and the MCNP5 code was used for calculating the neutron and gamma fluxes and dose rates. Results and Discussion: The neutron and gamma fluxes and dose rates due to DU on spherical surface of 30 cm radius were calculated with the variation of DU mass and density. In this calculation, an imaginary case in which DU density is zero was added to check the self-shielding effect of DU. In this case, the DU sphere was modeled as a point. In case of DU mixed with molten salt of 50-250 g, the neutron and gamma fluxes were calculated respectively. It was found that the molten salt contents in DU had little effect on the neutron and the gamma fluxes. The neutron and the gamma fluxes, under the respective conditions of 1 and 5 kg mass of DU, and 5 and $19.1g{\cdot}cm^{-3}$ density of DU, were calculated with the molten salt (LiCl+KCl) of 50 g fixed, and compared with the source term. As the results, similar tendency was found in neutron and gamma fluxes with the variation of DU mass and density when compared with source spectra, except their magnitudes. Conclusion: In the case of the DU mass over 5 kg, the dose rate was shown to be higher than the environmental dose rate. From these results, it is concluded that if a worker would do an experiment with DU having over 5 kg of mass, the worker should be careful in order not to be exposed to the radiation.

Cultural Conditions for Mass Production of Antagonistic Bacillus subtills CAP134 (길항균 Bacillus subtillis CAP134의 대량생산을 위한 배양조건)

  • 박흥섭;조정일
    • Korean Journal of Organic Agriculture
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    • v.5 no.1
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    • pp.87-99
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    • 1996
  • Cultural conditions for mass production of the antagonistic bacteria, Bacillus subtills CAP134 against pathogens causing major airborne diseases to apple tree, effect of temperature, pH, carbon and nitrogen source in the culture broth were investigated. The bacterial growth was most vigorous when the temperature and pH of the culture broth was 30~$35^{\circ}$C, and 7, respectively. As for carbon source, dextrose was best followed in order by dextrose(monosaccharides)>sucrose(disaccharides)$\geq$saccharose(di-saccharides)>starch (polysaccharides). Among different sugars, bacterial growth was favored by in the order of brown, black and white sugars, indicating that the bacterial growth might be promoted by the minor elements presented as impurities in the less purified sugars. As for nitrogen source, organic forms were better to bacterial growth than inorganic forms, that is polypeptone was best followed in order by soy sauce, soybeen milk and inoganic nitrogens. Differences in bacterial growth among different forms of inorganic nitrogen were negligible.

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Candida magnoliae SR101에 의한 Erythritol의 생산에서 산업용 질소원의 선정 및 최척화

  • Park, Seon-Yeong;Seo, Jin-Ho;Yu, Yeon-U
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.351-354
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    • 2001
  • In this experiment, we tested various nitrogen sources and then culture condition was optimized for industrial applications. The batch culture of Candida magnoliae SR101 grown in a defined medium supplemented with light steep water (LSW) as a sole nitrogen source showed a relatively high yield of erythritol production (53%), which was slightly higher than that using yeast extract as a nitrogen source, while the productivity and cell mass were maintained at similar levels. For the optimization of culture condition, the batch culture was performed. When the concentration of LSW was 65 mL/L in the defined medium containing 250 g/L of glucose, the concentration, yield and productivity of erythritol were 110 g/L, 44%, and 0.66 g/L-hr, respectively. The high yield and comparable productivity obtained with a cheap nitrogen source could be expected as a basis for the mass production of erythritol in the industrial scale.

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