• 천문학논총
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• 제30권2호
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• pp.521-523
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• 2015

The Milky Way did not form in isolation, but is the product of a complex evolution of generations of mergers, collapses, star formation, supernovae and collisional heating, radiative and collisional cooling, and ejected nucleosynthesis. Moreover, all of this occurs in the context of the cosmic expansion, the formation of cosmic filaments, dark-matter haloes, spiral density waves, and emerging dark energy. This paper summarizes a review of recent attempts to reconstruct this complex evolution. We compare simulated properties with various observed properties of the Local Group. Among the generic features of simulated systems is the tendency for galactic halos to form within the dark matter filaments that define a supergalactic plane. Gravitational interaction along this structure leads to a streaming flow toward the two dominant galaxies in the cluster. We analyze this alignment and streaming flow and compare with the observed properties of Local-Group galaxies. Our comparison with Local Group properties suggests that some dwarf galaxies in the Local Group are part of a local streaming flow. These simulations also suggest that a significant fraction of the Galactic halo formed at large distances and arrived later along these streaming flows.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 추계학술대회 논문집
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• pp.243-249
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• 2003

The head-on collision of two solitary waves are examined using a boundary element method. Attachment, detachment times and alplitudes and maximum run-up times and amplitudes are computed. Consolidation times show local minimum value if two waves are of equal amplitudes are colliding. Attachment times show local maximum value if the amplitudes of two waves are the same. The detachment time show local maximum if two wves are the same. The detachment amplitude show local minimum values if the amplitude e(=a/h) is greater than 0.3.

• Structural Engineering and Mechanics
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• 제2권3호
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• pp.269-284
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• 1994

The analysis and tests of thin-walled channel frames including nonlinear flexible or semi-rigid connection behaviour is presented. The semi-rigid connection behaviour is modelled using a mathematical approximation of the connection flexibility-moment relationship. Local instability such as local buckling and torsional flexural buckling of the member are included in the analysis. The full response of the frame, up to the collapse load, can be predicted. Experimental investigation was carried out on a series of simple double storey symmetrical frames with the purpose of verifying the accuracy and validity of the analysis. Agreement between the theoretical and experimental results is acceptable. The investigation also shows that connection flexibility and local instability such as local buckling and torsional flexural buckling can affect the behaviour and strength of thin-walled frames significantly. The results can also provide further insight into the advanced study of practical structures where interaction between flexible connections and phenomenon associated with thin-walled members are present.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 B
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• pp.543-545
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• 1999

In this paper, the composition method of global and local fuzzy reasoning concepts is researched for reducing the number of rules, not losing the performance for fuzzy controller. A new method is proposed in details that controls the interaction between global reasoning and local reasoning. In order to automatically acquire and optimize the method, the DNA coding algorithm is introduced to the local fuzzy reasoning of the proposed composition fuzzy reasoning method. The method is applied to the real liquid level control system for the purpose of evaluating the Performance. The simulation results show that the proposed technique can produce the fuzzy rules with higher accuracy and feasibility than the conventional methods.

• 한국해안해양공학회지
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• 제2권2호
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• pp.96-103
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• 1990

A local Iribarren number is suggested for the universal use of breaker type classification, which relates the bed slope to the wave steepness, both being given from the breaking point. The existing Iribarren number uses the wave length at an offshore point, while the local Iribarren number uses the wave length at the breaking point so that it can imply any influences due to current interaction and diffraction. The modified form of Miche's breaking criterion includes 고 breaking parameter which may be related to the local Iribarren number. Using the modifiedform of Miche's criterion with the local Iribarren number, the inclusion of Doppler effect seems to describe well the wave breaking mechanism in a current-interacted flow on a sloping beach without any additional effects implemented.

• 대한교통학회:학술대회논문집
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• 대한교통학회 2000년도 제37회 학술발표회논문집
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• pp.89-115
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• 2000

Traffic signal setting policies and traffic assignment procedures are mutually dependent. The combined signal control and traffic assignment problem deals with this interaction. With the total travel time minimization objective, gradient based local search methods are implemented. Deterministic user equilibrium is the selected user route choice rule, Webster's delay curve is the link performance function, and green time per cycle ratios are decision variables. Three implemented solution codes resulting in six variations include intersections operating under multiphase operation with overlapping traffic movements. For reference, the iterative approach is also coded and all codes are tested in four example networks at five demand levels. The results show the numerical gradient estimation procedure performs best although the simplified local searches show reducing the large network computational burden. Demand level as well as network size affects the relative performance of the local and iterative approaches. As demand level becomes higher, (1) in the small network, the local search tends to outperform the iterative search and (2) in the large network, vice versa.

• 한국콘텐츠학회논문지
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• 제13권2호
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• pp.235-243
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• 2013

이 연구는 지방분권을 위한 정책수단으로 재정분권이 어떠한 방식으로 이해될 수 있으며, 왜 필요한지에 대해 시스템사고의 이론을 바탕으로 지방재정시스템을 구성하는 변수들의 상호작용관계를 분석하였다. 연구를 통해 얻어진 결과는 다음과 같다. 첫째, 지방재정시스템을 구성하는 변수들은 상당한 수준에서상호작용관계가 형성되고 있으며, 5개의 양(+)의 피드백 루프가 중심이 되어 급속한 성장과 급속한 쇠퇴를 거듭한다는 점을 발견할 수 있었다. 둘째, 지방재정분권화의 타당성에 대한 전략 지점이 인과지도 모델링을 통해 발견되었다. 특히, 선순환구조를 악순환의 구조를 변질시키는 변수(국고보조금, 부동산거래과세, 중앙정부차원의 지방재정조정제도, 지방정부채무 등)이 지속적으로 작동함으로써 지방재정시스템을 쇠퇴시키는 것으로 나타났으며, 이를 바탕으로 전략적 정책과제가 도출 될 수 있었다. 이러한 연구는 지방재정분권에 대해 부분에 지식이 아닌 전체적 지식의 관점에서 지방재정시스템을 이해하고 지방재정의 학문적 폭을 높여 줄 것으로 판단된다.

• 한국전산구조공학회논문집
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• 제20권1호
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• pp.83-92
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• 2007

대형의 유체-구조물 연계시스템(FSI) 해석을 위해 많은 수치기법들이 있지만, 유체의 슬로싱에 의해 발생되는 집중적이고 불규칙한 동수압의 영향 때문에, 신뢰할 수 있는 수치 결과와 수치안정성을 확보하기 위해 매우 조밀한 메쉬를 필요로 한다. 그 결과, 신뢰할 수 있는 장기적인 시간 응답을 구하기 위한 수치해석은 상당히 많은 CPU 시간을 요구한다. 본 논문의 목적은 국부 상세 모델을 이용하여 LNG운반선의 화물창 시스템의 유탄성적 거동을 해석하기 위한 전역-국부 해석기법을 제시하고자 한다. 본 논문에서 제시한 해석기법의 타당성을 증명하고 이 기법을 통해 LNG운반선 화물창 시스템의 국부응답을 효율적으로 예측한 결과를 제시하였다.

• 산경연구논집
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• 제10권2호
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• pp.25-37
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• 2019

Purpose - The goal of this study is to analyze the differences in education performances between students of the government's financial support program and those who do not receive support at a local university in Korea. Research design, data, and methodology - The questionnaire used was NASEL. NASEL is considered a highly suitable survey tool for professors, courses, and performances in Korean universities. The 290 students who participated and 44 students do not participate in the financial support program were surveyed for 10 days. The characteristics of students were investigated by frequency analysis and technical statistics. The analysis of student collective characteristics used independent t and f-tests,and one-way ANOVA with IBM SPSS Statistics 22.0 for statistical purposes. Results - The p-value of the group receiving financial support and the group without financial support in active-collaborative learning is 0.167. The p-value of the economically supported group and the non-supported group of the faculty-student interaction is 0.281. The confidence coefficient of the active-collaborative learning questionnaire is 0.861. The reliability coefficient of the questionnaire for the faculty-student interaction questionnaire is 0.871. Conclusions - There are no clear differences in active-collaborative learning and faculty-student interaction between participating and non-participating students in the economic program.

• 한국주거학회논문집
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• 제22권3호
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• pp.1-14
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• 2011

'Sustainable Development' has become one of the most important concepts of the 21st century, and efforts are being made to actively apply this conception in various fields of social studies. Sustainability can be discussed in terms of economy, environment and society. In the case of social sustainability, a key motivation is the weakened bond within communities that is an unfortunate characteristic of modern society. The core of social sustainability is therefore in promoting 'social interaction and communication' through constructing communities and physical environments that support them. This study is based on the understanding that areal enlargement of physical environment doesn't guarantee the vitality of created community spaces. The purpose of this study is to deduce the design objectives and strategies of communal spaces in apartment complexes for social interaction and communication. Social interaction and communication can be divided into two aspects: between a complex and the local society, and within the complex itself. Nine design objectives are deduced from sixteen research reports published by public research institutions after 2000 and several design strategies are found through architectural analyses of influential examples based on 5 fundamental values of communal space planning.