• Journal of ILASS-Korea
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• v.22 no.4
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• pp.210-217
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• 2017

A gasoline direct injection engine has an intake air temperature can be lowered by the fuel vaporization in the combustion chamber increase the volume efficiency is high compression ratio. Therefore, study for injection rate and characteristics which influence mixture formation in combustion chamber is important. Movement of the injector needle has a direct effect on the injection of the fuel, such as formation of cavitation, the fuel injection rate, etc. Therefore, recent studies on the dynamic characteristics of the injector considering the movement of the needle have been reported, but it takes a lot of time and cost to experimentally confirm the movement of the needle inside the injector. In this study, AMESim, a commercial 1-D code, and Star-CCM+, a 3-D CFD code, were used to predict the dynamic performance of the injector with needle motion. In order to predict the movement of the needle under the high pressure, the result of the surface pressure distribution according to the movement of the needle was derived by using the morphing technique of flow analysis. In addition, we predicted the injection rate of the injector considering the movement of the needle in conjunction with the 1-D code. The injection rate of the injector was measured by the BOSCH's method and the results were similar to those of the simulation results. This method can predict the injection rate and injection characteristics and this result is expected to be used to predict the performance of gasoline direct injection engines with low cost and time in the future.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.83-86
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• 1996

We propose a mathematical model which describes the walking behavior of a person and to analyze the effect of the personality on the dynamics of the crowd. The fundamental assumption is that the human behavior is not a random process but a deterministic process with several basic mechanisms and each fundamental mechanism is common and only the parameter is different from person to person. The proposed model is based on the servomechanism which drives a person along the planned path from point to point. This model has been applied to simulate the walks of people in a crowd and the simulated results have a good coincidence with actual measurement.

• International Journal of Costume and Fashion
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• v.12 no.1
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• pp.29-48
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• 2012

The purpose of this study was to examine the relationship between consumer spatial behavior and consumer characteristics based on trade area selection criteria 469 female consumers who lived in the two new towns near Seoul, Bundang and Ilsan, participated in the study by completing questionnaires. Data were analyzed by using cluster analysis, ANOVA, Duncan's multiple range test, chi-square analysis, etc. The findings of the empirical research were as follows: 1. Five groups were identified by cluster analysis based on trade area selection criteria of clothing price-oriented group, time convenience-oriented group, shopping convenience-oriented group, variety/entertainment-oriented group, and passive shopping group. 2. Each group differed in spatial behavior such as clothing shopping area, the visiting frequency, and spatial movement type. 3. Each group showed differences in fashion involvement and demographic characteristics(age, marital status, education, occupation and social status).

• Journal of the Korean Society of Industry Convergence
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• v.3 no.3
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• pp.209-217
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• 2000

An attempt has been made to examine the highest liquid surface by means of measuring the movement of liquid free surface wave in the agitated vessel wall. Also, Relationship has been investigated between transition frequency, $N_z$ for behavior of liquid free surface and transition frequency for behavior of mass transfer coefficient in the agitated vessel wall. A surface wave is occured within agitated vessel, the highest height of wetted vessel wall, $h_w$ is coincided with the highest liquid surface, h. However the lowest height of wetted vessel, $h^*{_w}$ is not descended to lowest liquid free surface, $h^*$. The proposed model has been tested sucessfully for the behavior of liquid free surface.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.208.1-208.1
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• 2005

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2007.11a
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• pp.176-181
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• 2007

• Journal of Climate Change Research
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• v.5 no.2
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• pp.95-107
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• 2014

The 'Green Start Movement' is a practical movement of green living to efficiently reduce the greenhouse gases originating from non-industrial fields such as household, commerce, transportation, etc. for the 'materialization of a low carbon society through green growth (Low Carbon, Green Korea)'. When the new government took office, following the Lee Myeongbak Administration that had presented 'Low Carbon, Green Growth' as a national vision, it was required to set up the direction of the practical movement of green life to respond to climate change persistently and stably as well as to evaluate the performance of the green start movement over the past 5 years. A questionnaire survey was administered to a total of 265 persons including public servants, members of environmental and non-environmental NGOs, participants of the green start movement and professionals. In the results of the questionnaire survey, many opinions have indicated that the awareness of the green start movement is increasing and the green start movement has had a positive impact on individual behavior and group behavior in terms of green living. The result shows, however, that the environmental NGOs don't cooperate sufficiently to create a 'green living' effect on a national scale. Action needs to be taken on the community level in order to generate a culture of environmental responsibility. The national administration office of the Green Start Movement Network should play the leading role between the government and environmental NGOs. The Green Start National Network should have greater autonomy and governance of the network needs to be restructured in order to work effectively. Also the Green Start Movement should identify specific local characteristics to support activities that reduce greenhouse gas emissions. Best practices can be shared to reduce greenhouse gas emissions by a substantial amount.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.1
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• pp.34-44
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• 2021

In order to collect basic information of response behavior of red seabream (Pagrus major) during pilling, works for constructing wind power station in Byeonsan Peninsular, Korea were investigated. Four cultured red seabream CRB1 to CRB4 [total length (TL): 27.1 ± 1.0 cm; body weight: 359 ± 30 g] were tagged with an acoustic tag and used in experiment. CRB1 and CRB2 to CBR4 were released on the sea surface at same time around the constructing site of the wind power plant on September 22, 2017 and July 18, 2018, respectively. The tracking of the CRB1 to CRB2 and CRB3 to CRB4 were conducted for two hours, approximately, using VR100 receiver including a directional hydrophone and VR2W receivers array consisted of 19 presence/absence receivers (VR2W receivers), respectively. The underwater noise level before (no pile driving works) and during pile driving works was measured 116.0-118.0 dB (re 1��Pa) and a maximum of 160 dB (re 1��Pa), respectively. CRB1 moved about 6.0 km with average swimming speed of 80.2 ± 20.5 cm/s for 2.1 hours without pile driving work. The average water depth of the sea bed on the route of CRB1 was 9.1 ± 0.4 m. CRB2 moved about 7.3 km with the average swimming speed of 96.8 ± 27.1 cm/s for 2.1 hours with pile driving work. The water depth of the sea bed on the route of CRB2 was 11.9 ± 0.6 m. At results of the Rayleigh's z-test two fishes CRB1 and CRB2 showed significant directionality in the movement (p < 0.01). Movement mean angles of CRB1 and CRB2 were 92.7 and 251.8°, respectively. CRB2, CRB3 and CRB4 exhibited the escaping behavioral response from the noise of source during the pile driving work. The swimming speed of the CRB2 exposed on the heavy underwater noise stimuli due to the pile driving work was 1.21 times faster than that of the CRB1 exposed on the ambient underwater noise in the study site.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6C
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• pp.267-275
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• 2009

The steel pipe of steel-concrete composite piles increases the pile strength and induces the ductile failure by constraining the deformation of the inner concrete. In this research, the load-movement relations and the reinforcement effect by the outer steel pipe in the steel-concrete composite pile were analyzed by performing three-dimensional numerical analyses, which can simulate the yielding behavior of the pile material and the elasto-plastic behavior of soils. The parameters analyzed in the study include three pile materials of steel, concrete and composite, pile diameter and loading direction. As the results, the axial capacity of the composite pile was 1.9 times larger than that of the steel pipe pile and similar with that of the concrete pile. At the allowable movement criteria, the horizontal capacity of the composite pile was 1.46 times larger than that of the steel pile and 1.25 times larger than that of the concrete pile. In addition, the horizontal movement at the pile head of the composite pile was about 78% of that of the steel pile and about 53% of that of the concrete pile, which showed that the movement reduction effect of the composite pile was significant and enables the economical design of drilled shafts.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.189-195
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• 2002

In the area of pediatric dentistry, several behavior modification techniques have been attempted to relieve young patients' dental fear. The use of audio-visual(AV) aids is one of them and is increasing. In this study, several patients' reactions to dental treatment have been investigated after using AV aids, including patients' sleep, movement, crying and overall behavior. The effectiveness of AV aids have also been investigated through patients' age, previous dental experience and daily exposure to TV or video. Thirty healthy children with Frankl behavior rating (+) or (-) were included in this study. The average age of the children was $52.9{\pm}12.7$ months and no statistical difference was found between the two groups. Thirty patients were equally divided into two groups. Group I(control) received dental treatment with the conventional tell-show-do while group II(AV) with tell-show-do and AV aids. All patients received only restorative dental treatment and received no extraction. Houpt behavior rating scale was used to evaluate patients' behavior during the dental treatment. As a result, there was no significant difference between the two groups in movement and crying. However, more patients in the AV group fell asleep during the dental treatment compared to the control group. Within the AV group, patients with previous dental experience, older age and frequent exposure to AV materials showed better overall behavior during the dental treatment as audio-visual aids were used for behavior management.