• Journal of Korean Society for Atmospheric Environment
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• v.15 no.5
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• pp.587-598
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• 1999

In recent years emissions of pollutants from ship sources, especially NOx and SOx, is controlled by IMO(International Maritime Organization). The emissions of pollutants from ship sources in Pusan is considerably large, because the number of ship's coming and going in Pusan port is larger than that of other ports in Korea. Since Pusan is under the strong influence of land-sea breezes, pollutants emitted from ship sources will be transported into the inland. Control of emissions from ship sources is required to devise effectively the policy of air quality management in Pusan. Therefore this paper considered the present condition of total pollutant sources and emission characteristics including in coastal urban area.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.118-118
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• 2011

We executed a simultaneous survey of 22 GHz water maser and 44 GHz methanol maser toward 290 shocked $H_2$ emitting regions, which were identified from the galactic plane survey at $H_2$ 2.122 micrometer (UKIRT Widefield Infrared Survey for $H_2$; UWISH2). The primary goal of this observation is to characterize the H2 emission sources whether they are sincerely due to the outflows of young stellar objects or other shocked emission from older/evolved objects. We discovered 15 water maser sources and 15 methanol maser sources which provide the detection rate of around 5 percents. Most of detected sources have IRAS sources, infrared dark clouds, and/or submilimeter sources in the beam size of KVN single dish. In this poster, we will present the detailed results of our survey observation and discuss about the star formation rate in the galactic plane.

• International Journal of Control, Automation, and Systems
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• v.6 no.4
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• pp.613-619
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• 2008

A method to produce a desired current pattern in a multiple-source EIT system using voltage sources is presented. Application of current patterns to a body is known to be superior to the application of voltage patterns in terms of high spatial frequency noise suppression, resulting in high accuracy in conductivity and permittivity images. Since current sources are difficult and expensive to build, the use of voltage sources to apply the current pattern is desirable. An iterative algorithm presented in this paper generates the necessary voltage pattern that will produce the desired current pattern. The convergence of the algorithm is shown under the condition that the estimation error of the linear mapping matrix from voltage to current is small. Simulation results are presented to illustrate the convergence of the output current.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.749-754
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• 2003

In this paper, we introduce the measurement of the underwater noise with 32channel hydrophone array of Samsung CAvitation Tunnel (SCAT) and the detection technique of noise sources by using the beam-forming method. Measurement and way signal Processing under fluid flow are essential works for the underwater acoustics, especially for the detection of noise sources. As the acoustic impedance of the water is relatively high and the tunnel is an enclosed system, we have to consider the interaction between tunnel and water together with the reflection of noise in the beam-forming technique. Also, for a hydrophone array system that is fixed on one side of tunnel wall as done in SCAT is liable to suffer from some limitations in the detection of the noise sources with the array, we discuss these limitations particularly on the frequency range and spacing of noise sources.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.6
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• pp.9-17
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• 1994

ATM (Asynchronous Transfer Mode) has a fixed-length packet transport scheme. It is one of the promising proposals in B-ISDN.Since the packet length is fixed, it can be potentially to perform the various service to users. In this paper, a queueing model for an ATM multip`exer loaded by CBR and ON/OFF input sources is considered, and the two-queue system which each type of input sources has a queue with a finite capacity is analyzed. The cell loss probabilities for a performance measures of ATM multiplexer are derived, and are also evaluated through numerical examples. As a result, the cell loss probability of ON/OFF sources for the queue size is rapidly decreased when the multiplexed number and burstiness are increased. Since cells of the CBR source have lower priority than cells of the ON/OFF source, cell loss probabilities of CBR sources are accordingly high independently of CBR cell arrival rate when the number of CBR sources is large.

• Particle and aerosol research
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• v.14 no.4
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• pp.181-189
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• 2018

In this study, the risk rates of different contamination sources of the contaminant in a minienvironment were analyzed through Computational Fluid Dynamics (CFD) simulation. The airflow pattern characteristics can only predict the qualitative variation of contaminant concentration, but cannot evaluate the quantitative variations in the risk rate of sources. From the results, the ambient contamination sources mainly affect wafers in the Front Opening Unified Pod (FOUP), whereas the internal contamination sources mainly affect wafers laid on the robot arm in the minienvironment. And the purging plenum system is very useful in protecting the wafers in the FOUP from contaminants transferred from the Fan Filter Unit (FFU). However, this system is unable to protect the wafers on the robot arm from internal contaminants and the wafers in the FOUP from sources of the interface between the FOUP and the minienvironment.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.61.2-61.2
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• 2020

We study the overdensity of near-infrared sources around 508 sub-mm sources classified as dusty galaxies in the SPT-SZ survey catalog observed in 95 GHz (3.15 mm), 150 GHz (2 mm) and 250 GHz (1.2 mm) bands. We used the VISTA hemisphere survey data release 6 (VHS DR6) catalog covering the J, H, Ks bands. The mean number of galaxies within a radius of 60 arcsec (corresponding to about 500 kpc at z=2) from 500 randomly selected positions is 14.4, while the galaxy number distribution is approximated as a Gaussian with a standard deviation of 7.9. From the 2500 deg2 of SPT-SZ survey + VHS DR6 data, there were 27 sub-mm sources that have galaxy overdensity higher than 4σ. We present color-magnitude diagram around 27 selected sub-mm sources with enhanced galaxy surface densities, in order to investigate the presence of structure around sub-mm sources.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.6
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• pp.880-892
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• 2009

An overflow of information leads consumers to be easily distracted and to neglect the information being provided to them. E-tailers have to select types of information sources and provide their consumers with the most appropriate information. This study was done to specifically contribute to the research in proposing strategies of providing information of the Internet merchant to the e-shoppers through the analysis of relationships among the online purchase motives of consumers, the use of information sources, and decision making styles. This research categorizes the use of information sources into information sources concerning online stores and information sources concerning products. The uses of information sources relative to online stores are classified into the neutral, human, and marketer-oriented sources. The uses of information sources concerning the products are classified into the online and offline source. This study provides important suggestions for e-tailers to provide information about stores as well as products to the consumers with adaptable strategies.

• Journal of the Korean Geographical Society
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• v.42 no.5
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• pp.769-787
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• 2007

This study aims to uncover sources of environmental learning from a student perspective using the previously unstudied case of South Korea. literature from other countries credits many sources of learning, including: media, school, personal sources, and non-governmental organizations. This analysis is based on focus group and questionnaire data collected during in-country field work. Results from South Korea are then compared with other studies carried out in the Asia-Pacific and the Western developed world. The results show that, similar to other countries including Australia, China, and India; South Korean students learn about the environment mainly through the media and schools. Television, schools, and domestic internet web pages were found to be some of the most-used sources of environmental information in South Korea, while more personal sources, such as community, family, and friends, were found to play an overall lesser instructive role. When compared internationally, South Korean students often exhibited less trust in the reliability of various sources, especially business, community, and foreign sources of information.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.2
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• pp.150-160
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• 2014

Greenhouse gas (GHG) and Air Pollution (AP) emission inventories have been constructed and estimated independently up-to-date in Seoul. It causes difficulty in GHG and AP integrated management due to a difference in emission inventories. In this study, we constructed GHG and AP integrated emission inventories for direct and indirect sources in Seoul during the year 2010 in Energy activities for estimating GHG and AP emissions were derived from IPCC guideline, guidelines for local government greenhouse inventories, air pollutants calculation manual, and Indirect Emission Factors (IEF) reported by Korea Power Exchange. The annual GHG emission was estimated as 50,530,566 $tonCO_{2eq}$, of which 54.8% resulted from direct sources and the remaining 45.2% from indirect sources. Among direct sources, transportation sector emitted the largest GHG, accounting for 47.3% of the total emission from direct sources. As with indirect sources, purchased electricity sector only emitted 98.6% of the total emission from indirect sources. The annual AP emission was estimated as 283,701 tonAP, of which 85.9% was contributed by the combined AP emissions of transportation and fugitive sectors. Estimation of individual air pollutant showed that the largest source were transportation sector for CO, $NO_x$, TSP, $PM_{10}$ and NH3, non-energy sector for $SO_x$, and fugitive sector for VOCs. This study found some limitations in estimating GHG and AP integrated emissions, such as nonconforming emission inventories between GHG and AP, and no indirect AP emission factor of purchased electricity, and so on. Those should be further studied and improved for more effective GHG and AP integrated management.