• Title/Summary/Keyword: Forcing Frequency

Search Result 174, Processing Time 0.022 seconds

Dynamical Analysis of the Mooring Vessel System Under Surge Excitations (선박 계류시스템의 종방향 외력하의 비선형 동적거동 해석)

  • Lee, Sang-Do;You, Sam-Sang
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.24 no.2
    • /
    • pp.140-145
    • /
    • 2018
  • This paper deals with the dynamical analysis of a two-point mooring vessel under surge excitations. The characteristics of nonlinear behaviors are investigated completely including bifurcation and limit cycle according to particular input parameter changes. The strong nonlinearity of the mooring system is mainly caused by linear and cubic terms of restoring force. The numerical simulation is performed based on the fourth order Runge-Kutta algorithm. The bifurcation diagram and several instability phenomena are observed clearly by varying amplitudes as well as frequencies of surge excitations. Stable periodic solutions, called the periodic windows, can be obtained in succession between chaotic clouds of dots in case of frequency ${\omega}=0.4rad/s$. In addition, the chaotic region is unexpectedly increased when external forcing amplitude exceeds 1.0 with the angular frequency of ${\omega}=0.7rad/s$. Compared to the cases for ${\omega}=0.4$, 0.7rad/s, the region of chaotic behavior becomes more fragile than in the case of ${\omega}=1.0rad/s$. Finally, various types of steady states including sub-harmonic motion, limit cycle, and symmetry breaking phenomenon are observed in the two-point mooring system at each parameter value.

Spaciotemporal Distributions of PM10 Concentration and Their Correlation with Local Temperature Changes : a Case Study of Busan Metropolitan City (PM10 농도의 시공간적 분포 특징과 국지적 기온 변화 간의 상관관계: 부산광역시 사례 분석)

  • Park, Sunyurp
    • Journal of the Korean association of regional geographers
    • /
    • v.23 no.1
    • /
    • pp.151-167
    • /
    • 2017
  • The main objective of this study was to investigate the climatic impact of $PM_{10}$ concentration on the temperature change pattern in Busan Metropolitan City(BMC), Korea during 2001~2015. Mean $PM_{10}$ concentration of BMC has gradually declined over the past 15 years. While the highest $PM_{10}$ concentration was observed in spring followed by winter, summer, and fall on average, the seasonal variations of $PM_{10}$ concentration differed from place to place within the city. Frequency analysis showed that the most frequently observed $PM_{10}$ concentration ranged from $20{\mu}g/m^3$ to $60{\mu}g/m^3$, which accounted for 64.6% of all daily observations. Overall, the west-high and east-low pattern of $PM_{10}$ concentration was relatively strong during the winter when the effect of yellow-dust events on the air quality was weak. Comparative analyses between $PM_{10}$ concentration and monthly temperature slope derived from generalized temperature curves indicated that the decreasing trend of $PM_{10}$ concentration was associated with increases of annual temperature range, and $PM_{10}$ concentration had a negative relationship with the temperature slope of warming months. Overall, $PM_{10}$ concentration had a weak correlation with the annual mean temperature, but it had a significant, positive correlation with the winter season, which had a dominant influence on the annual mean temperature. In terms of energy budget, it has been known that the change in $PM_{10}$ concentration contributes to the warming or cooling effect by affecting the radiative forcing due to the reflection and absorption of radiant energy. The correlation between $PM_{10}$ concentration and temperature changes in the study area was not seasonally and spatially consistent, and its significance was statistically limited partly due to the number of observations and the lack of potential socioeconomic factors relevant to urban air quality.

  • PDF

Forced Flow Dryout Heat Flux in Heat Generating Debris Bed (열을 발생하는 Debris층에서의 강제대류 Dryout 열유속)

  • Cha, Jong-Hee;Chung, Moon-Ki
    • Nuclear Engineering and Technology
    • /
    • v.18 no.4
    • /
    • pp.273-280
    • /
    • 1986
  • The purpose of this study is to obtain the experimental data of the forced flow dryout heat flux in a heat generating debris bed which simulates the degraded nuclear reactor core after severe accident. An experimental investigation has been conducted of dryout heat flux in an inductively heated bed of steel particles with upward forced flow rising coolant circulation system under atmospheric pressure. The present observations were mainly focused on the effects of coolant mass flux, particle size, bed height, and coolant subcooling on the dryout heat flux The data were obtained when carbon steel particles in the size distribution 1.5, 2.5, 3.0 and 4.0 mm were placed in a 55 mm ID Pyrex glass column and inductively heated by passing radio frequency current through a multiturn work coil encircling the column. Distilled water was supplied with variation of mass flux from 0 to 3.5 kg/$\textrm{cm}^2$ s as a coolant in the tests, while the bed height was selected as 55 mm and 110 mm. Inlet temperature of coolant varied by 2$0^{\circ}C$ and 8$0^{\circ}C$. The principal results of the tests are: (1) Dryout heat flux increases with increase of upward forcing mass flux and particle size; (2) The dryout heat flux at the zero mass flux obviously depends on the Particle size as Previous studies; (3) The forced flow dryout heat flux in the shallow bed is somewhat higher than that in the deep bed,

  • PDF

The Effects of Food Service Franchisors' Conflict Resolution Activities on Procedure Quality, Behaviour Quality and Dissolution Intention (외식 프랜차이즈 본부의 갈등해결행동이 절차와 행동의 질 및 해지의도에 미치는 영향)

  • Han, Sang-Ho;Yang, Jae-Jang;Lee, Yong-Ki
    • The Korean Journal of Franchise Management
    • /
    • v.8 no.3
    • /
    • pp.29-37
    • /
    • 2017
  • Purpose - In recent years, research has been conducted on the conflict resolution strategies of the franchise headquarters and the franchisees, but there is a lack of research on the factors of conflict due to the intrinsic structure, such as interdependence or hierarchical relationship, and behavioral analysis to reduce the conflict. In this study, we analyze the relationship between satisfaction and trust formed in the process and result of the business, and the result of action to dissolution intention. Research design, data, methodology - For these purposes, the author developed the proposed model and several hypotheses. In this model, conflict resolution strategies consist of five dimensions such as avoiding, forcing, cooperating, obliging, and compromising strategy. And, this model proposed that onflict resolution strategies are antecedents of procedure quality, behaviour quality and dissolution intention are consequences of conflict resolution strategies. The data were collected from April 1 to April 15, 2013. Because this study examined franchise industries from the franchisee perspective, we contacted franchisee store owner and managers located in Seoul and Gyeonggi Province. Interviewers trained contacted a total of 483 franchisees, and 400 franchisees responded. Out of 400 respondents, 2 respondents were deleted due to missing information. Thus, a total of 398 franchisee were used for this study. he data were analyzed using frequency analysis, confirmatory factor analysis, correlation analysis, and structural equational modeling with SPSS 24.0 and Amos 23.0 statistical program. Results - The findings can be summarized as follows: First, franchisor conflict resolution activities have significant effects on procedure quality. Second, procedure quality has a significant effect on behavior quality. Finally, behavior quality has a significant effect on dissolution intention. Conclusions - In this study, we investigated the relationship between conflict resolution behavior, procedural quality, behavior quality and dissolution intention. As a result, the franchisers should strive to resolve conflicts not only in solving simple problems with franchisees, but also in a longer term perspective. We also found that the procedural aspects of resolving conflicts should not be ignored. If the trust and satisfaction of each other increase during the process of resolving the conflict, it will positively affect the satisfaction and trust in resolving the conflict. This is also because it serves to lower the intention of termination. However, there is a limitation that it is targeted only to the restaurant franchise, and it is necessary to study the conflict resolution behavior depending on the type of conflict.