• Proceedings of the Korea Water Resources Association Conference
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• 1986.07a
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• pp.131-145
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• 1986

흐름수역에서 연직상향으로 방류되는 평면부력\ulcorner의 거동이 연속방정식, 운동량방정식 및 추적물수송식의 기본방정식에 의하여 수치적으로 해석된다. 난류확산에는 Prandtld의 혼합거리이론을 도입한 난류수송모형이 이용된다. 수치해 과정은 기본방정식을 유함수(stream function)식, 와도수송(vorticity transport)식으로 변환한 후, \ulcorner방류속도와, 방류구폭 등으로 표현되는 변수와 흐름을 지배하는 무차원 매개변수를 도입하여 무차원 형태로 표현하는 부분과 successive under-relaxation과 Gauss-Seidel반복법으로 수행하는 부분으로 이루어진다. 적절한 relaxation 계수를 선정하므로써 안정되고 수렴성이 좋은 계산이 수행된다. \ulcorner방류 속도와 가로흐름 속도의 비가 속도비(Velocity ratio)로 정의되며 속도비가 8 - 15의 범위에서 부력\ulcorner으로 인한 주변흐름수역의 속도변화 온도상승범위, 흐름상태(유선) 및 와도가 조사되었으며 \ulcorner의 경로에 대하여 속도비와 방류밀도후르드수의 영향이 또한 조사되었다. \ulcorner중심선의 속도와 온도변화, 국부밀도후르드수의 변화가 구해지며 퍼짐율(dispersion ratio), 확산비(spreading rate)가 방류밀도후르드수, 국부밀도후르드수 및 방류구로부터의 경로의 항으로 해석되었다. 또한 속도와 온도 분포에 상사(similarity)가 존재함이 밝혀졌으며 본 연구와 같은 조건의 범위에서는 Gaussian분포를 이용한 적분형해석(intergal type analysis)이 가능한 것으로 사료된다.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.28 no.1
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• pp.45-77
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• 2017

Measurement of quality of life is a concept studied in the field of administration, economy and society. And It is a standard of measuring performance of government. Recently, in governments and global society, QoL (Quality of life) index is used to reflect overall development degree. National policy and service effectiveness measurement using QoL index is more persuasive when it is combined with 'Bottom-Up Spillover Theory'. This study applied "National Quality of Life Index", the object QoL index used by National Statistical Office to see if the library service is recognized to actually have influence on the quality of life, and furthermore, see the difference of quality of life improvement recognition by user and quality of life improvement degree recognized by the librarian. "Recognition regarding shortage of time" was the highest index, and "concentration of fine dust" was the lowest. Regarding the recognition difference between librarian and user, it showed signifiant difference in 13 index, while the recognition difference by gender showed difference in 5 index, difference by age was 23, difference by residence was 14, and difference by number of visits to library was 9.

• The Journal of Society for e-Business Studies
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• v.20 no.3
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• pp.59-77
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• 2015

Social networking sites (SNS), such as Facebook, provide abundant social comparison opportunities. Given the widespread use of SNSs, the purpose of the present study was to examine the impact of exposure to social media-based social comparison on user's negative emotions and discontinuous use intention on SNS. We present evidence that under the use of SNS, social comparison activities diverge into three patterns, with explicit self-evaluation desire made against similar target (lateral comparison), self-defense desire made against less fortunate target (downward comparison), and self-enhancement desire made with more fortunate target (upward comparison). Such social comparison processes frequently arise, as people are increasingly using on SNSs, the downward contacts ameliorating self-esteem with positive emotions, but the upward contacts and standard contacts with lateral status enabling a person to compare his or her situation with others and simultaneously increase negative emotions due to its differences with others. In other words, as people increasingly relying on SNSs for a variety of everyday tasks, they risk overexposure to upward or standard social comparison information that may have a cumulative detrimental impact on future intention on SNS use. This study with survey with 209 SNS users found that these negative emotions lead to negative fatigue (attitude) and then discontinuous use intention (behavior) on SNS. Our findings are among the first to explicitly examine discontinuous use intention on SNS using social comparison theory and our results are consistent with those of past research showing that upward social comparisons can be detrimental.

• Fire Science and Engineering
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• v.22 no.2
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• pp.63-69
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• 2008

The characteristics of the spread of a forest fire are generally related to the attributes of combustibles, geographical features, and meteorological conditions, such as wind conditions. The most common methodology used to create a prediction model for the spread of forest fires, based on the numerical analysis of the development stages of a forest fire, is an analysis of heat energy transmission by the stage of heat transmission. When a forest fire breaks out, the analysis of the transmission velocity of heat energy is quantifiable by the spread velocity of flame movement through a physical and chemical analysis at every stage of the fire development from flame production and heat transmission to its termination. In this study, the formula used for the 1-D surface forest fire behavior prediction model, derived from a numerical analysis of the surface flame spread rate of solid combustibles, is introduced. The formula for the 1-D surface forest fire behavior prediction model is the estimated equation of the flame spread velocity, depending on the condition of wind velocity on the ground. Experimental and theoretical equations on flame duration, flame height, flame temperature, ignition temperature of surface fuels, etc., has been applied to the device of this formula. As a result of a comparison between the ROS(rate of spread) from this formula and ROSs from various equations of other models or experimental values, a trend suggesting an increasing curved line of the exponent function under 3m/s or less wind velocity condition was identified. As a result of a comparison between experimental values and numerically analyzed values for fallen pine tree leaves, the flame spread velocity reveals a prediction of an approximately 10% upward tendency under wind velocity conditions of 1 to 2m/s, and of an approximately 20% downward tendency under those of 3m/s.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.1
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• pp.11-22
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• 1987

A plane buoyant jet discharged vertically upward into a crossflow is analyzed by numerical solution of the governing equations of continuity, momentum and constituent transport. The turbulent transport is modelled by the Prandtl's mixing length theory. In the numerical solution procedure, the governing equations are transformed by stream function and vorticity transport, non-dimensionalyzed by discharge velocity, slot width, and parameters representing flow characteristics, and solved by Gauss-Seidel iteration method with successive underrelaxation. The numerical experiments were performed for the region of established flow of buoyant jet in the range of discharge densimetric Froude number of 4 to 32 and in the range of velocity ratio of 8 to 15, which is the ratio of discharge velocity to crossflow velocity. Variations of velocities and temperatures, flow patterns and vorticity patterns of receiving water due to buoyant jet were investigated. Also investigated are the effects of velocity ratio and discharge densimetric Froude number on the trajectories of buoyant jet. Computed are velocities, temperatures and local densimetric Froude numbers along the trajectory of the buoyant jet. Spreading rate and dispersion ratio were analyzed in terms of discharge densimetric Froude number, local densimetric Froude number and distance from the source along the jet trajectory. It was noted that the similarity law holds in both the profiles of velocity and temperatures across the jet trajectory and the integral type analysis of Gaussian distribution is applicable.

• Journal of Service Research and Studies
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• v.13 no.4
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• pp.47-69
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• 2023

The main purpose of this study is to examine the mediating effects of performance satisfaction and audience loyalty through the motivation and community satisfaction of non-profit performance attendees in the local community. Motivations were examined by distinguishing between intrinsic and extrinsic factors to understand the profound desires of the audience. A survey was conducted targeting attendees who had experienced non-profit performances in the Jeju area over the past year to gather data. Ultimately, the survey responses from 363 participants were used as the basis for analysis. The results of the analysis indicated that higher levels of intrinsic and extrinsic motivations generally led to greater satisfaction and loyalty towards performances (H1, H2, H3). However, extrinsic motivation did not directly influence loyalty (H4). Nevertheless, both types of motivations were found to positively influence loyalty through performance satisfaction (H5, H8). While satisfaction with performances did not have a direct impact on community satisfaction (H6), audience loyalty was found to have a positive influence on community satisfaction (H7). Regarding motivations, performance satisfaction did not mediate the relationship between motivations and community satisfaction (H9). In the case of audience loyalty, intrinsic motivation showed mediating effects, while extrinsic motivation did not (H10). The process of motivation-satisfaction-loyalty-community satisfaction demonstrated a sequential pathway (H11). In conclusion, if local residents show interest and participate in non-profit performances, they develop a positive perception of the respective community. Therefore, performances provided at the local level should be recognized as crucial elements for the development of the community.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.545-555
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• 2020

The purpose of this study is to derive the linkage between urban regeneration and district unit planning, in order to supplement the limitations of the spread of the effects of individual urban regeneration projects. To this end, institutional changes and previous studies with theoretical backgrounds were reviewed, the urban regeneration strategic plan and district unit plan cases in the spatial scope of Jeju Island were analyzed, and a unified administrative procedure to strengthen linkages was proposed. In addition, when selecting priorities for active regions, we reviewed how to use the indicators of involvement of residents, which enabled the project to be performed smoothly by grasping the participation of residents and the elements of complaints. Also a hypothetical target site was set up and suggested how to establish a district unit plan by type. Depending on the circumstances and environment of the site, the use of the land use plan and the regulation and mitigation of the district unit plan may be appropriately used to expect the inhabitants to expand their participation and revitalization. This study suggests ways to revitalize decayed areas beyond systematic urban planning in connection with systematic plans, to improve administrative procedures, and to promote bottom-up projects.