• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제25회 KOSCI SYMPOSIUM 논문집
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• pp.49-56
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• 2002

A two-dimensional direct numerical simulation is performed to investigate the formation characteristics of a single vortex interacting with $CH_4/N_2$-Air counterflow nonpremixed flame. The numerical method was based on a predictor-corrector scheme for a low Mach number flow. The detailed transport properties and a 16-step augmented reduced mechanism are adopted in this calculation. The budgets of the vorticity transport equation arc examined to reveal the mechanisms leading to the formation, evolution and dissipation of a single vortex interacting with counterflow nonpremixed flame. It is found that the stretching term, which depends on the azimuthal component of vorticity, and radial velocity, mainly generates vortieitv in non-reacting and reacting flows. The viscous and baroclinic torque term destroy the vorticity in non-reacting flow. In addition, the baroclinic torque term due to density and pressure gradient generates vorticity, while viscous and the volumetric expansion terms due to density gradient destroy vorticity in reacting flow.

• 한국조경학회:학술대회논문집
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• 한국조경학회 2007년도 Journal of Landscape Architecture in Asia Vol.3
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• pp.66-71
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• 2007

The settlement era($1845{\sim}1943$) in Shanghai was divided as periods parting point by the establishment of habitats, the establishment of the International Settlement and its two times expansions, the establishment of the French Settlement and its three times expansions. Investigations on the formation process and its characteristics of two settlement parks during each period were carried out. The formation process of Shanghai settlement park was divided simply into the settlement park foundation time correspond to the settlement expansion time(the International Settlement was from 1845 to 1898, the French Settlement was from 1849 to 1913) and the settlement park development time after the settlement expansion(the International Settlement is from 1899 to 1943, the French Settlement is from 1914 to 1943) by the characteristics such as its forming time, quantity and distribution.

• 웰빙융합연구
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• 제7권3호
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• pp.43-53
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• 2024

Purpose: his study aims to explore how healthcare provider service characteristics in telemedicine services, which have become more common since the pandemic, affect rapport formation and service satisfaction with healthcare providers. Research design, data and methodology: A group of actual telemedicine users underwent data collection and empirical analysis. After analyzing reliability and validity, hypotheses were tested using a structural equation model. Results: Key perceived attributes of healthcare providers in telemedicine services were identified as doctor effort, doctor listening, and doctor expertise. Each of these variables had a significant positive impact on trust in telemedicine. Moreover, these attributes significantly positively impacted rapport formation and user service satisfaction, which was mediated by trust. However, the direct impact of rapport formation on service satisfaction was not supported. Conclusions: The study's findings have academic and practical implications for expanding telemedicine services. As an initial empirical study on telemedicine services, it confirms the importance of trust and rapport formation even in non-face-to-face medical situations. In order to overcome the limitations of non-physical contact, telemedicine services should strive to develop UI/UX designs that are more interoperable and boost trust in service apps.

• 한국분무공학회지
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• 제1권2호
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• pp.50-56
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• 1996

In an fuel injection type gasoline engine, atomization of fuel droplet and mixture formation process are very important to understand engine combustion efficiency, and also has influence directly on the decision of engine performance and pollutant emission. In this study, perforated throttle valve instead of solid type throttle valve was developed and equipped to an SPI engine to promote secondary atomization and good droplet-air mixture formation. From the engine performance lest. it was verified that the case of perforated valve kas more advantages in each experimental parameters such as in cylinder gas pressure, mass burnt ratio, fuel consumption rate, and pollutant emission characteristics than that of solid one equipped. No matter what the same perforated valve, there are some distinct results in engine performance characteristics according to the perforate ratio.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제30회 춘계학술대회논문집
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• pp.343-346
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• 2008

초음속 주 유동내 연료의 수직분사 유동장에 대한 비정상 3차원 수치해석이 DES 난류 모델을 이용하여 수행되었다. 해석 결과는 시간에 따른 에디의 위치 및 에디 생성 빈도에 대하여 실험과 비교되었다. DES 난류 모델은 에디의 대류 특성을 비교적 정확하게 모사하고 있는 반면에 에디 생성 빈도는 다소 과대 예측하고 있다.

• 한국기계가공학회지
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• 제8권3호
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• pp.13-20
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• 2009

Development of a dynamic engine model is essential to predict and analyze of dynamic characteristics from a natural gas engine. Reducing the harmful exhaust emissions can be accomplished by a precise air-fuel ratio control. In this paper, the dynamic engine model was proposed and included mixture formation and intake process because the dynamic characteristics can be affected by the mixture components such as an air and a gaseous fuel. The air mass flow, the partial pressure ratio, and the gas constant are changed by variations of the components in the mixture formation and intake process. The dynamic engine model is applied to the natural gas engine for validation test. Experimental results show that the dynamic engine model is effective to predict the dynamic characteristics of the natural gas engine.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제5권3호
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• pp.222-229
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• 2005

This paper presents a self-organizing scheme for multi-agent swarm systems based on coupled nonlinear oscillators (CNOs). In this scheme, unicycle robots self-organize to flock and arrange group formation through attractive and repulsive forces among themselves. The main result is the maintenance of flexible and scalable formation. It is also shown how localized distributed controls are utilized throughout group behaviors such as formation and migration. In the paper, the proposed formation ensures safe separation and good cohesion performance among the robots. Several examples show that the proposed method for group formation performs the group behaviors such as reference path following, obstacle avoidance and flocking, and the formation characteristics such as flexibility and scalability, effectively.

• 한국항공우주학회지
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• 제35권1호
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• pp.18-26
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• 2007

날개들이 편대를 이루면서 비행하는 경우의 정상상태 공력특성에 대하여 와류격자법을 이용하여 해석하였다. 2개의 날개가 편대 비행 상태에 있을 때, 선도 날개에 의하여 후방 날개의 부분 양력계수가 높아짐을 알 수 있었다. 3개 이상의 날개를 일렬 및 V자편대 배치하여 양항비에 대하여 해석하였는데, 날개가 편대의 후방에 위치할수록 커지고, 가로 간격이 벌어질수록 작아짐을 알 수 있었다. 가로세로비가 증가할수록 전방 날개와 후방 날개의 양항비 차이가 커짐을 알 수 있었다. 후방 날개의 높이를 변화시켰을 경우, 같은 높이에서 최대 양항비를 나타내었다. 3개, 9개, 15개의 날개를 편대 비행했을 경우 날개 수가 많아질수록 편대 비행의 이득이 증가함을 알 수 있었다.

• International Journal of Computer Science & Network Security
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• 제21권9호
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• pp.118-124
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• 2021

The article examines the formation of a competitive paradigm of economic security of industrial enterprises in the formation of a circular economy. The basic laws of industrial enterprises are formed, which determined the characteristics of competitive positions and threats. The basic competitive concepts and their application at maintenance of economic safety of the industrial enterprises in the conditions of formation of circular economy are described. Thus, the technological approach to the formation of a competitive paradigm is based on production technologies, opportunities for technological modernization and development of infrastructure and intellectual competencies. The institutional concept reveals the regulatory mechanisms for ensuring competitiveness through the protectionism of national industrial enterprises, standardization and regulation of market imbalances. The innovation-investment approach within the competitive paradigm is also manifested in the creation of competitive advantages due to the presence of active innovative developments and their commercialization, knowledge and competencies of staff, capitalization of intelligence and communications, constant updating of infrastructure and technologies. Collectively, innovation and investment effects on the level of economic security allow industrial enterprises to ensure resilience to increasing competition, the emergence of new market challenges in the formation of a circular economy. A strategic approach to the application of a competitive paradigm to ensure the economic security of industrial enterprises allows you to justify the prospects for development and design behavioral models to predict and assess potential threats. The concept of system management is based on the complexity of threat analysis, the integrity of the economic security system, system-forming functions and patterns of implementation of industrial development tasks in the formation of a circular economy. The application of the described concepts is formalized by the authors through the definition of the basic patterns, directions and characteristics of their impact on the elements of the security system of industrial enterprises in the formation of a circular economy.

• 한국의류학회지
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• 제25권4호
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• pp.817-827
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• 2001

This study tried to investigate whether characteristics of the perceiver and image of ideal woman made differences in the important factors for the selection clothing and the preference of clothing. A poll of 650 men & women between the ages of 20-39 living in Daegu was taken for this study. Factor analysis, cluster analysis, frequency, ANOVA-test, t-test, and $\chi$$^2$-test were implemented with the SPSS-package. The characteristics of clothing types used in this study included: sexy, masculine, feminine, dramatic, elegant-classic, and casual. The results were as follows. 1. In the situation of first impression formation, the characteristics of the perceiver made differences in the selection of clothing types. Women took self-satisfaction and fashion factors to be more important than men, so did persons in their 20s than 30s. And the unmarried took self-satisfaction factor to be more important than the married. 2. Men and women had different images of the ideal woman. Under special situations of first impression formation, such as, formal blind dates on the condition of marriage and casual blind dates, there were differences in clothing preference.