• Transactions of The Korea Fluid Power Systems Society
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• v.2 no.3
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• pp.1-5
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• 2005

There are two types of solenoid actuator for force and position control of the fluid power system. One is an on-off solenoid actuator and the other is an electro-magnetic proportional actuator. They have some different characteristics for attraction force according to solenoid shape. Attraction force of the on-off solenoid actuator only depends on flux density. And the stroke-force characteristics of the proportional solenoid actuator are determined by the shape of the control cone. In this paper, steady state characteristics of the solenoid actuator for electro-hydraulic proportional valve determined by the shape of control cone are analyzed using finite element method and it is confirmed that the proportional solenoid actuator has a constant attractive force in the control region independently on the stroke position. And the shape of control cone is optimized using 1+1 evolution strategy to get a constant force. In the optimization algorithm, control cone length, thickness and taper length are used as a design parameter.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.48 no.11
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• pp.611-616
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• 1999

The introduction of the eddy current braking(ECB) system in HSRT(high speed railway train) is known to be advantageous, in that the system is independent on wheel-rail adhesion coefficient which is greatly affected by weather condition. It also minimize the maintenance of the brake system and does not require any additional electric energy because it is powered form the regenerated power at the time of the braking. In this study, the braking and attraction forces of the ECB are simulated by 2-D FEM and are experimentally verified on a down-scaled prototype. A control algorithm of the ECB is proposed to generate constant braking torque using linear variation of the reference current according to speed. Experimental results shows that the constant torque is generated over all operating speed region by developed control algorithm.

• Land and Housing Review
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• v.11 no.3
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• pp.39-48
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• 2020

Gamcheon village was a poor village in the past, but it recently has boomed as a representative tourists' attraction in the region. Its unique topography and history have played a significant role in the town's growth as a famous tourists' attraction. The factors contributed decisively to the formation of a special spatial structure there. In the process of the town's rapid development as a tourists' destination, however, the tourism overflowed. As such, the interests of the residents and the tourists conflicted, and the segregation between the two has augmented. These gaps seem to have enormously distorted the perception of the spaces as much as they have seriously distracted the existing traffic circulations in the village. The purpose of this study is to identify the differences in spatial perception of both residents and tourists in the Gamcheon village. For the purpose, it assumes the residents' natural movements and the tourists' purposeful movements, and they are analyzed by the space syntax. The major findings are that the circulations of the residents and the tourists in the village are clearly separated and that the two groups perceive the same space completely differently. This confirms the fact that even the same space could be recognized and used in a totally different way depending on the users' purposes.

• International Journal of Advanced Culture Technology
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• v.8 no.4
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• pp.153-160
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• 2020

The purpose of this study is to investigate the effect of female college students' participation in dance sports, perception of body attractiveness, and importance of body attractiveness. For this study, female university students residing in Gwangju Metropolitan City and Jeonnam region in 2019 were selected as the population. A total of 350 people were selected as the study subjects, but 170 dance sports participants and 130 non-participants were selected for the study, excluding 50 copies of double written and unfaithful data. After individually entering coded data into the computer, the statistical program (SPSS Windows.20.0 Version) was used. The results obtained through this research process are as follows. First of all, it was found that there was a difference in perception of body attractiveness depending on whether female university students participated in dance sports. Second, it was found that there was a difference in the importance of physical attractiveness depending on whether female college students participated in dance sports. Third, it was found that female college students' perception of body attractiveness has an effect on the importance of body attractiveness.

• The Journal of the Korea Contents Association
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• v.10 no.10
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• pp.398-407
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• 2010

The purpose of this study is to explain the neighborhood region "gimpo northwest area" connection development make use of a core tourist area "kanghwado" of visitor behavior characteristics. this is a foundation data for research of kanghwado behavior characteristics. For this research, the description of the current study were as follows. First kanghwado revisitors of high potentialities visit gimpo northwest area. so its demanded same or different attraction development and make an target marketing from kanghwado revisitors. Second the gimpo northwest keep the accent on development history and experience education of housewives families. Third publicity board parking area and infrastructure is demanded on the 48th street. Forth Han river and Imjin river meeting point gimpo north area, each other kanghwado gimpo west put opposite Yeomha river there can see point the west sea. therefore we need waterside attraction.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2702-2707
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• 2007

The purpose of this study is to calculate the behavior of molecules for the generation of homogeneous thin-films in the process of spray deposition. The calculation system was composed of a suface molecular region and droplet molecular region. The thin-film was generated when droplet molecules fell to surface molecules. Lennard-Jones potential had been used as intermolecular potential, and only attraction 때 d repulsion had been used for the behavior of the droplet on the solid surface. As results, the behavior of the droplet was so much influenced by the surface temperature in the spray deposition process. High temperature of surface has higher porosity and larger spread area. It was found that simulation results generally agreed well with previous the experimental results. This simulation result will be the foundation for the deposition processes of industry.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.739-744
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• 2001

In order to investigate the stability of magneto-rheological fluid based squeeze film damper (MR-SFD), its negative stiffness effect, which arises from magnetization of MR-SFD, is identified theoretically and experimentally. The analytical model of MR-SFD includes the magnetic circuit as well as the displacement stiffness associated with the squeeze mode of MRF. Extensive experiments are carried out to measure the magnetic attraction forces generated in the MR-SFD, with the excitation frequency and the eccentricity of the journal varied, which are controlled by an active magnetic bearing. The simulation and experimental results are found to be in good agreement. It is concluded that the negative stiffness effect dominates only in the low frequency region because its effect diminishes in the high frequency region due to the eddy-current loss.

• Korean journal of applied entomology
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• v.41 no.4
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• pp.233-238
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• 2002

The seasonal occurrence trends of the brown-winged green bug, Plautia stali, and the brown malmorated stink bug, Halyomorpha halys, were monitored in sweet persimmon orchards in southern region of Korea using light traps (in 2000 and 2001), and aggregation pheromone traps (methyl (E, E, Z)-2 ,4, 6-decatrienoate)) of P. stali (in 2001). Light trap data showed that H. halys started to occur from the end of June, and reached its peak in early or mid August, while P. stali was mostly attracted to the traps from mid July to late August without any distinct attraction peak. Both species did not occur after September in the persimmon orchards studied. The attraction patterns of both species to aggregation pheromone traps were different from those observed in light traps. Both species were attracted to the pheromone traps from mid May to late August. The peak occurrence of H. halys could not be detected due to low catches. However, the period of peak attraction for P. stali was from late June to late August depending on the geographical locations. The aggregation pheromone traps of P. stali attracted more number of P stali than H. hails, but the light traps showed a reverse pattern. In both species, more females were attracted to the aggregation pheromone traps than males. The difference of attraction patterns between 2 types of traps was discussed in relation to content of soluble tannin in persimmon fruits.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.1
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• pp.29-42
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• 2019

In order to expand the qualitative aspects of public facility, this study used SNS data to derive user-oriented preference factors for public facilities and then were quantified in terms of supply side and demand side. To derive preference factor, LDA, one of topic modeling, was used and attraction index was calculated for each facility. In addition we analyzed spatial accessibility to measure the degree of service experience of users by using 2SFCA model. The study area covered public libraries of Seoul, Korea. As a result of study, five topics were extracted as preference factors for the public library: Circumstance, Scale of facility, Cultural program, Parenting, Books and materials. In particular topic of circumstance and parenting were newly derived preference factors unknown in previous studies. As a result of calculating attraction index for each library, the index of Songpa Library, Jungdok Library, and Namsan Library was high. Songpa library has received good evaluation in parenting factor, and Jungdok & Namsan library in circumstance factor. The accessibility of each region seems to better in center of Seoul where public libraries are crowded, but shrinking toward the outskirts. We expect that the proposed method will contribute to user-oriented public facility evaluation and policy decision making.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.1
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• pp.385-393
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• 2021

This study investigates the effect of infrastructure, economic sectors and its status, foreign direct investment and private investment, as well as the role of political stability in enhancing the tourism demand in the ASEAN region. The research collected the secondary data from the World Bank database and the UNWTO website of 10 ASEAN countries over 17 years from 2000 to 2016. Applying the generalized method of moments, this research found that, "private investment", "economic sectors", "exchange rate and infrastructure measured by "using of the internet" can increase the tourism demand of a country in the ASEAN region. This research provided evidence indicating that the "foreign direct investment" and "inflation" are two detrimental factors for tourist attraction. The major finding confirmed the positive role of "political stability" in increasing tourist arrivals. First, attracting tourists to a country always poses many challenges to its government. It has been observed in the past decades that though there were many documents, which confirmed that industry can help in promoting tourism, very few studies investigated the role of both agriculture and manufacturing sectors in tourism promotion. Secondly, there are only a few studies which verifies the stability of the political system to the tourism demand in the ASEAN region and that this variable (political stability) has the strongest impact.