• Title/Summary/Keyword: Neighborhood interaction

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Do Inner Planets Modulate the Solar Wind Velocity at 1 AU from the Sun?

  • Kim, Jung-Hee;Chang, Heon-Young
    • Journal of Astronomy and Space Sciences
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    • v.31 no.1
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    • pp.1-6
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    • 2014
  • Quite recently, it has been suggested that the interaction of the solar wind with Mercury results in the variation in the solar wind velocity in the Earth's neighborhood during inferior conjunctions with Mercury. This suggestion has important implications both on the plasma physics of the interplanetary space and on the space weather forecast. In this study we have attempted to answer a question of whether the claim is properly tested. We confirm that there are indeed ups and downs in the profile of the solar wind velocity measured at the distance of 1 AU from the Sun. However, the characteristic attribute of the variation in the solar wind velocity during the inferior conjunctions with Mercury is found to be insensitive to the phase of the solar cycles, contrary to an earlier suggestion. We have found that the cases of the superior conjunctions with Mercury and of even randomly chosen data sets rather result in similar features. Cases of Venus are also examined, where it is found that the ups and downs with a period of ~ 10 to 15 days can be also seen. We conclude, therefore, that those variations in the solar wind velocity turn out to be a part of random fluctuations and have nothing to do with the relative position of inner planets. At least, one should conclude that the solar wind velocity is not a proper observable modulated by inner planets at the distance of 1 AU from the Sun in the Earth's neighborhood during inferior conjunctions.

Do Inner Planets Modulate the Space Environment of the Earth?

  • Kim, Jung-Hee;Chang, Heon-Young
    • Journal of Astronomy and Space Sciences
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    • v.31 no.1
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    • pp.7-13
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    • 2014
  • Variabilities in the solar wind cause disturbances throughout the heliosphere on all temporal and spatial scales, which leads to changeable space weather. As a view of space weather forecasting, in particular, it is important to know direct and indirect causes modulating the space environment near the Earth in advance. Recently, there are discussions on a role of the interaction of the solar wind with Mercury in affecting the solar wind velocity in the Earth's neighborhood during its inferior conjunctions. In this study we investigate a question of whether other parameters describing the space environment near the Earth are modulated by the inner planets' wake, by examining whether the interplanetary magnetic field and the proton density in the solar wind observed by the Advanced Composition Explorer (ACE) spacecraft, and the geomagnetic field via the Dst index and Auroral Electrojet index (AE index) are dependent upon the relative position of the inner planets. We find there are indeed apparent variations. For example, the mean variations of the geomagnetic fields measured in the Earth's neighborhood apparently have varied with a timescale of about 10 to 25 days. Those variations in the parameters we have studied, however, turn out to be a part of random fluctuations and have nothing to do with the relative position of inner planets. Moreover, it is found that variations of the proton density in the solar wind, the Dst index, and the AE index are distributed with the Gaussian distribution. Finally, we point out that some of properties in the behavior of the random fluctuation are to be studied.

A study on Locational and Regional Pattern of Leisure Facilities at Kangnam-gu, Seoul (서울시의 활동여가시설의 입지유형에 관한 연구 - 강남구를 중심으로 -)

  • Choi, Woun-Sik;Kim, Min
    • Journal of the Korean Regional Science Association
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    • v.10 no.2
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    • pp.17-29
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    • 1994
  • This study attempts to examine the regional distribution and the locational pattern of leisure facilities at Kangnam-gu in Seoul. For the convenience of the analysis the facilities are classified into public and private sector and then the facilities are classified into 11 types: mineral spring resort, play ground, neighborhood park, swimming pool, gymnasium, bowling, pingpong, aerobic, golf practice, health, and billiard facilities. For the purpose data was collected from statistical yearbook in 1993 and lists of registered facility at department of living physics of Kangnam-gu office. The data of the density of facilities and the opportunity of facilities per facilities type and per region are analysed with the technology of GIS. Results may be summarized as follows. First of all, correlation between the results of Location-Allocation model and the results of Interaction model is very high. Secondly, on comparing the density of facilities with the opportunity of the facility use per eleven facility types, three discrete spatial pattems are found. The mineral spring resort facility type with the highest unbalanced density and opportunity of facility use is to be found. Play ground, neighborhood park, swimming pool, gymnasium, bowling, pingpong, and aerobic facility types have the high unbalanced density and opportunity of facility use. The golf practice, health, and billiard facility types have spatially balanced density and opportunity of facility use. Thirdly, as comparing the density and the opportunity of the facility use per 'dong' administration unit, the spatial patterns of the public and the private facilities are different in density of the facility use and otherwise two are similar in the opportunity of the facility use. Fourthly, patterns of facilities users have different charateristics based on facility use time, expense, residence, and access time and four regional patterns are to be found ; user favorable, facility profitable, user balanced, and unfavorable.

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Unsupervised Machine Learning based on Neighborhood Interaction Function for BCI(Brain-Computer Interface) (BCI(Brain-Computer Interface)에 적용 가능한 상호작용함수 기반 자율적 기계학습)

  • Kim, Gui-Jung;Han, Jung-Soo
    • Journal of Digital Convergence
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    • v.13 no.8
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    • pp.289-294
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    • 2015
  • This paper proposes an autonomous machine learning method applicable to the BCI(Brain-Computer Interface) is based on the self-organizing Kohonen method, one of the exemplary method of unsupervised learning. In addition we propose control method of learning region and self machine learning rule using an interactive function. The learning region control and machine learning was used to control the side effects caused by interaction function that is based on the self-organizing Kohonen method. After determining the winner neuron, we decided to adjust the connection weights based on the learning rules, and learning region is gradually decreased as the number of learning is increased by the learning. So we proposed the autonomous machine learning to reach to the network equilibrium state by reducing the flow toward the input to weights of output layer neurons.

Context-Dependent Classification of Multi-Echo MRI Using Bayes Compound Decision Model (Bayes의 복합 의사결정모델을 이용한 다중에코 자기공명영상의 context-dependent 분류)

  • 전준철;권수일
    • Investigative Magnetic Resonance Imaging
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    • v.3 no.2
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    • pp.179-187
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    • 1999
  • Purpose : This paper introduces a computationally inexpensive context-dependent classification of multi-echo MRI with Bayes compound decision model. In order to produce accurate region segmentation especially in homogeneous area and along boundaries of the regions, we propose a classification method that uses contextual information of local enighborhood system in the image. Material and Methods : The performance of the context free classifier over a statistically heterogeneous image can be improved if the local stationary regions in the image are disassociated from each other through the mechanism of the interaction parameters defined at he local neighborhood level. In order to improve the classification accuracy, we use the contextual information which resolves ambiguities in the class assignment of a pattern based on the labels of the neighboring patterns in classifying the image. Since the data immediately surrounding a given pixel is intimately associated with this given pixel., then if the true nature of the surrounding pixel is known this can be used to extract the true nature of the given pixel. The proposed context-dependent compound decision model uses the compound Bayes decision rule with the contextual information. As for the contextual information in the model, the directional transition probabilities estimated from the local neighborhood system are used for the interaction parameters. Results : The context-dependent classification paradigm with compound Bayesian model for multi-echo MR images is developed. Compared to context free classification which does not consider contextual information, context-dependent classifier show improved classification results especially in homogeneous and along boundaries of regions since contextual information is used during the classification. Conclusion : We introduce a new paradigm to classify multi-echo MRI using clustering analysis and Bayesian compound decision model to improve the classification results.

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Phenomenological Study of the Lived Experience of Elderly People (현상학적 접근을 통한 노인의 삶의 경험)

  • Huang, Bo-Sun;Shin, Yu-Sun;Yun, Suk-Ok;Lee, Ji-Hyun;Jung, Kyung-Yim;Kim, Jung-Soon;Kim, Lee-Soon;Kim, Bok-Yong;Kang, Young-Mee
    • Research in Community and Public Health Nursing
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    • v.6 no.2
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    • pp.133-160
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    • 1995
  • The purpose of this study was to understand the structure of the lived experience by poor elderly people. The research question was 'What is the structure of the lived experience of life of a poor elderly people.' The sample consisted of 21 single poor elderly persons in Pusan. The unstructured interviews were audio-recorded and analyzed using the Van Kaam method. This study was 368 responses which yielded of descriptive expressions and priority classifications. The result generated 74 common elements, 18 syntheses of hypothetical definitions and 5 identifications of the structural definition. The structural definitions and hypothetical definitions were as follows; 1. physical discomfort ; complaints of severe pain ; dysfunction of physical organs 2. emotional cognition ; despair ; resignation ; attitude toward death 3. support system ; interaction with family ; thinking about God ; economical difficulties ; expectancy of social services ; opinions about health service ; leisure ; interaction with neighborhood ; dissatisfaction due to inadequate environment 4. past reminiscence ; negative reminiscence of one's past ; past regret ; positive reminiscence of one's past 5. desire ; desire of unrealization life ; self satisfaction The significance of this study for nursing are; Comprehension of the lived experience of client and identification' of nursing approach method concerning the lifestyle of client.

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Computational Study on Unsteady Aerodynamic Loads on Crossing Train (교행하는 고속전철의 비정상 공기력에 대한 수치적 연구)

  • Hwang, Jae-Ho;Lee, Dong-Ho
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.599-604
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    • 2000
  • In order to study unsteady aerodynamic loads on high speed trains passing by each other at the speed of 350km/h, three-dimensional flow fields around trains during the crossing event are numerically simulated using the three-dimensional Euler equations. The Roe's FDS with MUSCL interpolation is employed to simulate wave phenomena properly. An efficient moving grid system based on domain decomposition techniques is developed to analyze the unsteady flow field induced by the restricted motion of a train on a rail. The numerical simulations of the trains passing by on the double-track are carried out to study the effect of the train nose-shape, the train length and the existence of tunnel when the crossing event occur. Unsteady aerodynamic loads side force and drag force-acting on the train during the crossing are numerically predicted and anlayzed. It is found that the strength of the side force mainly depends on the nose-shape, and that of drag force on tunnel existence. And it is observed that the push-pull like impulsive force successively acts on each car and acts in different directions between the neighborhood cars. The maximum change of the impulsive force reaches about 3 tons. These aerodynamic force data are absolutely necessary for the evaluation of the stability of the high speed multi-car train. The results also indicate the effectiveness of the present numerical method for the simulation of unsteady flow field induced by the bodies in the relative motion.

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Concept Establishment of Territoriality of External Public Space of Housing Complex - Focusing on review of previous research -

  • Kim, Jin-Soo;Kim, Jin-Mo
    • KIEAE Journal
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    • v.15 no.5
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    • pp.59-66
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    • 2015
  • Purpose: Recently, Housing area plan has tried to reflect a public space of various forms. However, most of cases are indiscriminately developments, which don't reflect the diverse needs of residents. In addition, a subject of the public space is not clear and consistently stable of the management, so the residents don't have an interest enough to take advantage of it. Method: In order to make a plan of the public space of a residential complex, an architect designer needs to take a few things into consideration. One is a physical facility in needs. And other one is a management of keeping a social place stably and consistently, which allows residents to be able to interact with each other. It should be regarded for residents to form a sense of belonging, while minimizing the interface friction. When all these problems are fulfilled, an interaction will be made to improve the quality of the living environment. Result: Therefore, in this study, it is necessary to define the meaning of territoriality of the external public space of housing complex. This study makes it possible to improve the relationship of neighborhood and the quality of the life for the residents, depending on the time. This is the first step as 'the research for the territoriality of the external public space of housing complex', in order to define about the concept, function, characteristic of territory(the base of territoriality) and to establish the territoriality that can form the physical or psychological boundary in public space.

Reinventing Vacant Lands for Urban Agriculture: Evaluating Milwaukee's Vacant Land Programs and Initiatives (도시농업을 활용한 유휴공간의 재발견: 밀워키를 사례로)

  • Kim, Minji
    • Land and Housing Review
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    • v.11 no.2
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    • pp.59-68
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    • 2020
  • Converting vacant lands for urban agriculture has become a popular topic for American cities to engage in on a program and policy level. The advocates of urban agriculture cite a number of potential benefits, ranging from promoting sustainable urban development, fostering social interaction and educational opportunities, regenerating neighborhoods, and empowering residents. With the emergence of vacant lands in South Korea, different strategies have been implemented for productive use. Nonetheless, less attention has been paid to reinvent vacant lands for urban agriculture. Therefore, this study has examined the case of the City of Milwaukee's vacant land initiatives and programs that were known to have brought a series of positive neighborhood revitalization outcomes. Compared to the case of Milwaukee, intensive land use and high property prices have turned to be the major actors that prevent an active use of vacant land for urban agriculture within the context of South Korean cities. Thus, this paper proposes the possibility of using vacant lands in apartment complexes for urban agriculture.

Approximation-Based Decentralized Adaptive Output-Feedback Control for Nonlinear Interconnected Time-Delay Systems (비선형 상호 연결된 시간 지연 시스템을 위한 함수 예측 기법에 기반한 분산 적응 출력 궤환 제어)

  • Yoo, Sung-Jin
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.2
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    • pp.174-180
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    • 2012
  • This paper proposes a decentralized adaptive output-feedback controller design for nonlinear interconnected systems with unknown time delays. The interaction terms with unknown delays are related to all states of subsystems. The time-delayed functions are compensated by using appropriate Lyapunov-Krasovskii functionals and function approximation technique. The observer dynamic surface design technique is employed to design the proposed memoryless local controller for each subsystem. In addition, we prove that all signals in the closed-loop system are semiglobally uniformly bounded and control errors converge to an adjustable neighborhood of the origin.