• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.6
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• pp.115-121
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• 2011

This study is about comparison of tangental entry type cyclone dust collector with axial vane type cyclone dust collector. Cut diameter and dust collection efficiency of both collector was compared by theory and experiment. Cut diameter was calculated by an quasi-empirical formula by Lapple and Shepherd. Measurement of cut diameter was conducted by particle counter through dust generator. As the result, cut diameter obtained by experiment was a little larger than that by theory. But the error is within $0.5{\mu}m$ in both type of collector, so it could be confirmed that theoretical value and experimental value were almost identical. And, as flow rate increased, dust collection efficiency was increased. Also axial vane type showed higher dust collection efficiency than tangental entry type. Therefore, it can be said that axial vane type cyclone dust collector has higher performance than the other.

• Journal of Families and Better Life
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• v.34 no.3
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• pp.95-111
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• 2016

The purpose of this study was to compare the factors affecting mother's satisfaction, word-of-mouth, and repurchase intention for the complete collection and monography picture books. Questionnaires from 323 5-year-olds' mothers in Seoul and Kyunggi province were analysed. The findings are as follows. Firstly, mother's product involvement and dual readership, and child's preference for picture books were common effective factors to improve mother's satisfaction, word-of-mouth, and repurchase intention. Secondly, reflection of child's opinions explained mother's satisfaction, word-of-mouth, and repurchase intention only for the monography, not for the complete collection. Thirdly, mother's product involvement had a direct effect on the repurchase intention of monography, while mother's subjective knowledge was more important for the repurchase intention of the complete collection.

• Journal of Environmental Science International
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• v.10 no.5
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• pp.351-358
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• 2001

The main purpose of this study was to investigate the characteristics of cylindrical electrostatic precipitator with centrifugal effect in viewpoints of pressure drip and collection efficiency, experimentally. The experiment was carried out for the analysis of current-voltage, pressure drop and collection efficiency with various experimental parameters such as the applied voltage, inlet velocity, inlet size and inlet type(upper and bottom), etc. In the results, the pressure drops were estimated as 27~54, $34~63mmH_2O$ for inlet size $15mm{\tiems}30mm$ and $30mm{\tiems}60mm$, respectively. The collection effeciencies were shown over 90% with the small inlet size($15mm{\tiems}30mm$) for the applied voltage 40kV, inlet velocity(15~21m/s), and 51~89% with the large inlet size ($30mm{\tiems}60mm$). Moreover, in the applied voltage 0kV and inlet size $15mm{\tiems}30mm$, the collection efficiency induced by centrifugal force was represented as about 35% with inlet velocity 15 - 21m/s.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.3
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• pp.237-250
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• 1998

In this study, the characteristics of electrostatic bag filter to overcome the main problems such as the high pressure drop and low collection efficiency for submicron particles are investigated with the experimental parameters. Especially, the experiment is carried out focusing on collection efficiency and pressure drop change mechanism as a function of discharge electrode shapes and filter properties, including the applied voltages, filtration velocities and particle concentrations, etc . Results show that the collection efficiency is improved over 30% for the fine particle below 1 pm and pressure drop reduction ratio (PDRR) increases in the following order 4 mm screwy > 4 mm square > 4mm round discharge electrodes . For the filter properties, Nomex is more effective than PE under the influence of electrostatic force. Applying 30 kV for a screwy discharge electrode, higher overall collection efficiency is maintained in spite of the increment of filtration velocity over four times (8 m/min) in comparison with that of 2 m/min and PDRR are highly shown over 80o1o with various filtration velocities, 5, 8, 11 m/min.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.2
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• pp.185-192
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• 2014

The main object of this study was to investigate the collection characteristics of wet-type cyclone with wall cavity. The experiment was executed to analyze the characteristics of pressure drop and collection efficiency for the present system with the experimental parameters such as water spray, water spray type, inlet velocity etc. In results, for the present system of wet-type, the pressure drop represented 35 mm $H_2O$, while in dry-type 33 mm $H_2O$ showing lower 6% at $v_{in}=21m/s$. In case of $v_{in}=21m/s$ and water spray 200 mL/min, the collection efficiency of the present system became significantly higher as 96.8% comparing to that of the conventional wet-type scrubber. Additionally, for 200 mL/min, $SO_2$ removal efficiencies decreased with the increment of inlet velocity representing 75.0, 62.5, 50.0%, at $v_{in}=6,9,12m/s$, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.318-325
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• 2014

The main object of this study is to investigate the collection characteristics of wet-type rotating porous disk system experimentally. The experiment is carried out to analyze the pressure drop and collection efficiency for the present system with the experimental parameters such as system inlet velocity, stage number, tube diameter, inlet concentration, etc. In results, for the present system, at 5 stage and ${\upsilon}_{in}=1.8m/s$, the pressure drop becomes significantly lower as $64mmH_2O$ in comparison with that of the conventional wet type scrubber (Venturi scrubber, over $250mmH_2O$). The collection efficiencies increase with higher inlet velocity showing 92, 95.7, 98.4%, while $SO_2$ removal efficiencies decrease with increment of inlet velocity as 80, 65, 50% at ${\upsilon}_{in}=1.08$, 1.44, 1.8 m/s and tube diameter $D_t=10mm$, respectively. The present system is to be considered as an effective compact system for a simultaneous removal of particle/gas phase pollutants from marine diesel engines.

• Journal of Korea Game Society
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• v.21 no.2
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• pp.67-78
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• 2021

Since the release of and in 2017, business models for collection mobile games have been changing. Collection Mobile games are composed mainly of characters, and the business model is also highly related to user preference factors. The Delphi method and the AHP analysis were used on ten experts in each field of game production to identify preference factors, and five collection mobile games were selected for business model analysis. The result shows that 'moe' characters are a major preference factor, and accordingly, business models are also changing to focus on the completion of character collection and products such as character skins.

• Journal of Digital Convergence
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• v.18 no.5
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• pp.441-453
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• 2020

This study conducted a questionnaire survey on SNS users who are conducting K-POP record collection activities using SNS and verified factors affecting the intention to continue K-POP record collection activities. The main methods of analysis were exploratory factor analysis, confirmatory factor analysis, correlation analysis, and path analysis using SPSS 21.0 program and AMOS 21.0 program. The results are summarized as follows. First, compatibility for K-POP record collection activities through SNS has a positive effect on perceived usefulness, and observability also has a positive effect on perceived usefulness and perceived ease of use. Second, perceived ease of use for K-POP records collection using SNS has a positive effect on perceived usefulness. Third, perceived usefulness and perceived ease of use for K-POP records collection using SNS have a positive effect on continuous intention of K-POP records collection activity through SNS. As a result of this study, it suggests that the intention to continue the collection activities of K-POP records using SNS can be explained through the integration of innovation diffusion theory and technology acceptance model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.9
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• pp.598-605
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• 2014

In this paper, we suggest a modified slotted ALOHA algorithm for fast tag collection in active RFID system and implement the reader and tag operation using CC2530 chip of Texas Instruments Co. to prove the performance of the proposed algorithm. In the present international standard related with active RFID including ISO/IEC 18000-7 the reader sends sleep command to each tag after successful obtaining tag's information. Meanwhile, in this paper, the tags decide to sleep after checking the second command from the reader resulting in enormously decreased tag collection time. We tested the proposed algorithm with 30 tags over the range of 0-3m and the results showed that the tag collection process was completed in 400msec at average. And 30 tags are collected in one second with 99.7% and the collection rate is 100% in 2m distance between reader and tag. The collection rates are 99.94% and 99.7% for distance 2.5m and 3m, respectively. The average collection rate is 99.91% over all range and it is concluded that the proposed algorithm is enough to apply to real fields.

• Korean Journal of Social Welfare
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• v.63 no.2
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• pp.5-29
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• 2011

This paper analyzed the integration cases of the social insurance systems of Germany, Sweden and United Kingdom. On the basis of the two dimensions - institutional and organizational integration, this study reviewed the historical processes of the social insurance integration of the three countries. In Germany, the institutions and the organizations are divided still now and the sickness insurance funds take charge of the entitlement and collection services. In Sweden, the social insurance system is divided by institutions but the organizations were united. the Inland Revenue has charge of the entitlement and collection. In UK, the institutions and the organizations were united and the entitlement and collection services is assigned to the Inland Revenue. Regarding these historical processes of the social insurance integration of developed countries, this paper evaluated the transfer of the collection service to the National Health Insurance Corporation in Korea, which was enforced in 2011.