• Title/Summary/Keyword: Source Characteristics

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Dose Characteristics by the Co-60 Source Oscillations in High Dose Rate After Loading Irradiations (고선량율 원격강내조사의 코발트-60 이동선원에 의한 선량특성)

  • 최태진;김옥배;노홍균
    • Progress in Medical Physics
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    • v.1 no.1
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    • pp.51-60
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    • 1990
  • Dose distributions around Co- 60 moving source in high dose rate remote afterloading unit, Buchler 3K unit, were experimented with X-omat V films and calculations. In our experiments, film dosimetries have achieved to evaluated the axial dose distributions for source oscillations were 0, 3.5, 5.0 and 6.0 cm in periodically, In results, the dose distributions in axial of source movement showed apparently higher than in transverse direction caused by source locations, dwelling time and air gap in the applicator. In the calculations, the dose rate was derived by using the inverse square law, filteration corrections and Meisberger constant for scatter corrections as source movings. In our experiments and calculations, the average dose uncertainties were showed -2.1$\pm$1.9% in fixed sourdce, -2.9$\pm$1.8%, -7.4$\pm$6.1% and -6.7$\pm$4.6% at 3.5 cm, 5.0 cm and 6.0 cm source oscillations, but the calculations have showed very close to experimental dose rate within 4 cm distance from source.

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Characteristics of PM2.5 in Gyeongsan Using Statistical Analysis (통계분석을 이용한 경산 지역의 초미세먼지(PM2.5) 농도 특성 파악)

  • Li, Kai Chao;Hwang, InJo
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.6
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    • pp.520-529
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    • 2015
  • The ambient $PM_{2.5}$ samples were collected by $PM_{2.5}$ sampler from September 2010 to December 2012 at Daegu University, Gyeongsan. A total of 260 samples were collected and 27 species were analyzed by inductively coupled plasma, ion chromatography, and thermal optical reflectance methods. Factor analysis identified four sources such as biomass burning source/secondary aerosol source, soil source, industry source, and incinerator source/mobile source. Also, backward trajectories were calculated using HYSPLIT 4 (Hybrid single-particle lagrangian integrated trajectory) model and PSCF (Potential source contribution function) model was applied to identify the possible source locations of carbonaceous species and water soluble ions species. PSCF results showed that the possible source locations of most chemical constituents measured in Gyeongsan were the industrial areas in the eastern coast of China, northeast regions of China, the Gobi Desert, and east sea of Korea.

Stormwater Runoff Characteristics of Non-point Source Pollutants according to Landuse of Urban Area (도시지역 토지이용에 따른 비점원 오염물질 유출특성)

  • Jeong, Dong-Hwan;Shin, Dongseok;Rhew, Doughee;Jung, Dongil
    • Journal of Environmental Impact Assessment
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    • v.16 no.6
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    • pp.525-532
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    • 2007
  • In order to establish and implement the total maximum daily load (TMDL) management plan in Korea, it is necessary to set the source units and calculate discharge loads for non-point source pollutants such as BOD, COD, SS, TN and TP. This study analysed the corelation between stormwater runoff characteristics and event mean concentrations (EMCs) of non-point source pollutants. As the result of the corelation analysis, we knew that all the antecedent dry days (ADD) and the rainfall correlated lowly with non-point source pollutants in the urban areas such as resident area, industrial area, business area, road area and parking area. Therefore, it is necessary to get all samples from stormwater starting point to stormwater ending point and standardize the sampling method of stormwater in order to obtain more accurate EMCs for landuse.

A design and implementation of the traffic source model considering user's moving characteristics in urban areas (도시 사용자 이동특성을 고려한 traffic source model의 설계 및 구현)

  • 유기홍
    • Journal of the Korea Computer Industry Society
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    • v.2 no.11
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    • pp.1373-1382
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    • 2001
  • Traditionally, Mobile Teletraffic model consists of two sub-models, i.e. the network traffic model and the traffic source model. In this paper, we present the traffic source model by developing MobCall(Mobile Call Simulator) which analyses various mobile wireless environments based on regional characteristics that the base stations are located. User mobility is presented by regional average vehicle speeds and the transportation share rate. Moreover, the user mobility on subway, which is increasing in urban area, is considered in MobCall. Using MobCall, the accumulated number of calls in residential and commercial regions, the handoff rate with respect to traffic sources of Seoul, the handoff rate on highway, and the handoff rate according to the call duration are presented. MobCall enables the simulation of dynamic handoff buffering and functional entity control of one base station according to the changes in user's calling pattern at the design phase.

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Verification of Effectiveness of the Standard Floor Impact Source by Comparing with Living Impact Sources (실생활 충격소음을 통한 표준 바닥충격원의 실효성 검증)

  • Park, Hyeon Ku;Kim, Kyeong Mo;Kim, Sun-Woo
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.23 no.12
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    • pp.1117-1126
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    • 2013
  • The standard impact sources, standardized to rate the sound insulation performance of floor structure, should simulate well the real floor impact sources, which is very important to grade the floor structure then to establish counter plan to improve the performance of floor. Recently the tire, the standard heavyweight impact source, has been discussed that the impact force is too big to represent the real impact force. And researches have been carried on the applicability as a substitute or a supplementary. In addition, tapping machine, the standard lightweight impact source, is also questionable if it is representative of real lightweight impact source. This study aims to examine the similarity of standard impact sources with living impact sources, comparing the physical characteristics such as impact force, frequency contents and sound level. The result showed that the physical characteristics of standard impact sounds were somewhat different with that of living impact sounds, and the standard sources couldn't be verified from this result. Later subjective evaluation should be followed to compare how the physical differences make relationship with the subjective differences.

A Study of affect on credibility of information source and word-of-mouth acceptance by word-of-mouth information characteristics on SNS (SNS에서 구전정보의 특성이 정보원에 대한 신뢰와 구전수용에 미치는 영향)

  • Park, Jong Soon;Lee, Jong Man
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.10 no.3
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    • pp.327-338
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    • 2014
  • The purpose of this study is to investigate what the characteristics of word-of-mouth on SNS and how these factors credibility for information's source and acceptance of word-of-mouth. We proposed study model was set through overall theoretical investigation. The 179 Valid survey data were gathered from the user who have prior experience in SNS. According to factor analysis, characteristic of word-of-mouth information on SNS were classified into consensus and neutrality. And credibility for information's source and acceptance of word-of-mouth were composed sing dimension. The Hypothesis inspection says that all variables were positively correlated with each other. And consensus and valance have positive influence on credibility for information's source. Also credibility for information's source influence on acceptance of word-of-mouth and valance have positive affect trust for information's source. Several academic and practical implications are yield accordingly. Especially this study intention to provide basis which can be used for all business's effective marketing activity.

Technical Procedure for Identifying the Source of Nitrate in Water using Nitrogen and Oxygen Stable Isotope Ratios (질소 및 산소 안정동위원소 활용 수계 질산성 질소 오염원 판별을 위한 기술 절차 제안)

  • Kim, Kibeum;Chung, Jaeshik;Lee, Seunghak
    • Journal of Soil and Groundwater Environment
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    • v.27 no.2
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    • pp.87-98
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    • 2022
  • This study aims to prepare a technical protocol for identifying the source of nitrate in water using nitrogen (δ15N) and oxygen (δ18O) stable isotope ratios. The technical processes for nitrate sources identification are composed of site investigation, sample collection and analysis, isotope analysis, source identification using isotope characteristics, and source apportionment for multiple potential sources with the Bayesian isotope mixing model. Characteristics of various nitrate potential sources are reviewed, and their typical ranges of δ15N and δ18O are comparatively analyzed and summarized. This study also summarizes the current knowledge on the dual-isotope approach and how to correlate the field-relevant information such as land use and hydrochemical data to the nitrate source identification.

Spatially Mapped GCC Function Analysis for Multiple Source and Source Localization Method (공간좌표로 사상된 GCC 함수의 다 음원에 대한 해석과 음원 위치 추정 방법)

  • Kwon, Byoung-Ho;Park, Young-Jin;Park, Youn-Sik
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.5
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    • pp.415-419
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    • 2010
  • A variety of methods for sound source localization have been developed and applied to several applications such as noise detection system, surveillance system, teleconference system, robot auditory system and so on. In the previous work, we proposed the sound source localization using the spatially mapped GCC functions based on TDOA for robot auditory system. Performance of the proposed one for the noise effect and estimation resolution was verified with the real environmental experiment under the single source assumption. However, since multi-talker case is general in human-robot interaction, multiple source localization approaches are necessary. In this paper, the proposed localization method under the single source assumption is modified to be suitable for multiple source localization. When there are two sources which are correlated, the spatially mapped GCC function for localization has three peaks at the real source locations and imaginary source location. However if two sources are uncorrelated, that has only two peaks at the real source positions. Using these characteristics, we modify the proposed localization method for the multiple source cases. Experiments with human speeches in the real environment are carried out to evaluate the performance of the proposed method for multiple source localization. In the experiments, mean value of estimation error is about $1.4^{\circ}$ and percentage of multiple source localization is about 62% on average.

Knitwear Consumers′Demographic Characteristics and Evaluation Criteria

  • Han, Sung-Ji;Kim, Moon-Sook
    • The International Journal of Costume Culture
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    • v.3 no.2
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    • pp.136-146
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    • 2000
  • The purpose of this study was to investigate the effect of demographic characteristics and general buying characteristics of knitwear consumers on evaluation criteria and information source searching. In this study, a self-administered questionnaire was distributed to young career women and female undergraduate students. Of 580 questionnaires, 496 were used in the following analysis. The data was analyzed with the SPSS package. The research method used factor and reliability analysis to segment consumers by their knitwear evaluation criteria. T-test, one-way ANOVA and χ²were used to characterize the impact of characteristics of the consumer on knitwear evaluation criteria and information source searching in buying knitwear. The results of this study were as follows. First, the information sources of consumers were significantly different depending on their demographic characteristics(age). According to the difference in relationship between the age of consumers and information sources, the younger the consumer, the more information in fashion magazine, the older, in fashion advertisement on catalog. Second, the knitwear evaluation criteria of consumers was classified according to six characteristics - quality, price, aesthetic, situation, self-expression and external. Their knitwear evaluation criteria were significantly different depending on demographic characteristics(job, age, education, marital status) and the general buying characteristics of knitwear(annual knitwear/clothing buying expense and frequency). Career women and married women placed significant importance on practical aspects like quality and price characteristics, while undergraduate students and single women placed significant importance on practical aspects like quality and price characteristics, while undergraduate students and single women placed significant importance on aesthetic and self-expression characteristics. Also, a group with higher annual knitwear/clothing buying expense and frequency considered aesthetic and self-expression characteristics more important. The lower the annual knitwear/clothing buying expense and frequency, the higher a group considered quality and price characteristics more important.

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