• Title/Summary/Keyword: space technology

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Polynomial Fuzzy Radial Basis Function Neural Network Classifiers Realized with the Aid of Boundary Area Decision

  • Roh, Seok-Beom;Oh, Sung-Kwun
    • Journal of Electrical Engineering and Technology
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    • v.9 no.6
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    • pp.2098-2106
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    • 2014
  • In the area of clustering, there are numerous approaches to construct clusters in the input space. For regression problem, when forming clusters being a part of the overall model, the relationships between the input space and the output space are essential and have to be taken into consideration. Conditional Fuzzy C-Means (c-FCM) clustering offers an opportunity to analyze the structure in the input space with the mechanism of supervision implied by the distribution of data present in the output space. However, like other clustering methods, c-FCM focuses on the distribution of the data. In this paper, we introduce a new method, which by making use of the ambiguity index focuses on the boundaries of the clusters whose determination is essential to the quality of the ensuing classification procedures. The introduced design is illustrated with the aid of numeric examples that provide a detailed insight into the performance of the fuzzy classifiers and quantify several essentials design aspects.

Research of the public service advertising using interactive media in public space (공공 공간에서 인터랙티브 미디어를 이용한 공익 광고 디자인에 관한 연구)

  • Li, Cheng;Park, Sanghyun
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.933-937
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    • 2009
  • Interactive multi-media advertising is a new field with broad space of research coming into being with the emergence and extensive application of computer multi-media technology. This text analyzes the existing application in the advertisement of mutual media at first. Secondly analyze the public service advertisement design in the mutual media and public space. Through to in the public space, utilize to public service advertisement design and analysis of the mutual media, To characteristic and advantage of the mutual media, make the application of the public service advertisement to carry on research on the public space.

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Disturbance-Observer-Based Robust H Switching Tracking Control for Near Space Interceptor

  • Guo, Chao;Liang, Xiao-Geng
    • International Journal of Aeronautical and Space Sciences
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    • v.15 no.2
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    • pp.153-162
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    • 2014
  • A novel robust $H_{\infty}$ switching tracking control design method with disturbance observer is proposed for the near space interceptor (NSI) with aerodynamic fins and reaction jets. Initially, the flight envelop of the NSI is divided into small subregions, and a slow-fast loop polytopic linear parameter varying (LPV) model is proposed, to approximate the nonlinear dynamic of the NSI, based on the Jacobian linearization and Tensor-Product (T-P) model transformation approach. A disturbance observer is then constructed, to estimate the modeled disturbance. Subsequently, based on the descriptor system method, a robust switching controller is developed, to ensure that the closed-loop descriptor system is stable with a desired $H_{\infty}$ disturbance attenuation level. Furthermore, the outcome of the proposed switching tracking control problem is formulated as a set of linear matrix inequalities (LMIs). Finally, simulation results demonstrate the effectiveness of the proposed design method.

Mechanism and Behavior Characteristic of Space Truss Unit for Post-tensioning

  • Kim, Jin-Woo;Kim, Sang-Jin
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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    • v.6 no.1
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    • pp.38-43
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    • 2003
  • This paper presents the results of a post-tensioning test and analysis of a pyramidal unit structure that is basic element for space structures. The behavior characteristics was analyzed and compared with the numerical analysis and the mechanism in test model was confirmed with geometrical analysis. The results of this paper show that the behaviors of space structures can be predicted in multi-directional Mero joint system. And the authors suggest the possibility of erection and shaping formation with comparatively small post-tensioning, and space structure with the mechanism should consider the nonlinear behavior due to large deformation.

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Behaviour Characteristic of Grid Dome Shaped Space Structures by Post-tensioning (포스트텐션에 의한 격자 돔형 공간 구조의 거동 특성)

  • 김진우
    • Journal of Ocean Engineering and Technology
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    • v.16 no.1
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    • pp.41-45
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    • 2002
  • This paper is concerned with the erection and ultimate load test of dome shaped space structures by post-tensioning. It is a fast and economical method for constructing such a dome by post-tensioning of the cable in bottom chords. This structure consists of uniform pyramids in a flat layouts on the ground, and then the structure is shaped and erected into its final curved space structure. Ultimate load test was performed for dome shaped space structures. The feasibility of the proposed erection method and the reliability of the established geometric model were confirmed with numerical analysis and experimental investigation on a small scale steel model. As a results we can find the most reasonable modeling technique for the prediction of shape formation in practices and we can know the characteristic of the behaviour in ultimate load test for practical design purposes.

KSLV-II Cost Estimate using TRANS COST 7.1 (TRANSCOST 7.1을 적용한 실용위성 발사체 비용추정)

  • Seo, Yun-Kyoung;Oh, Bum-Seok
    • Aerospace Engineering and Technology
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    • v.6 no.2
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    • pp.119-125
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    • 2007
  • Space launch vehicle development needs many kinds of technologies synthetically. Nowadays, KARI (Korea Aerospace Research Institute) has developed a space launch vehicle, KSLV-I (Korea Space Launch Vehicle-I), that is able to load with an 100kg payload. After that it plans to develop Korean Space Launch Vehicle. As space launch vehicle becomes more complicate and larger, it needs a scientific and analytic development cost estimation. In this paper a cost estimation for KSLV-II using TRANSCOST 7.1 was studied.

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An Approach to Sensibility Technology for a Plan of Bathroom (욕실공간 계획을 위한 감성공학적 접근)

  • 윤정숙
    • Journal of the Korean Home Economics Association
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    • v.35 no.3
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    • pp.171-179
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    • 1997
  • The purpose of this research was to grasp the space funtions, the preferred image in bathroom and to find out the plan of bathroom. The subjects of investigation included university students in third decades of which data were obtained by the questionnaire survey method. The major findings were as follows: 1) The space funtions of bathroom were the hygienic activities and the supplementary funtions as resting and health-care. 2) Total and facility image in bathroom take a serious view of a sanitary, a function and following to a mood , a sense of space. 3) The preferred type of bathrooms were identified as the 2-space type. Furthermore, the demands were needed in radiator & pannel heating system, storing furniture and funtional lighting & mirror. According to those results, three types of space plan for bathroom can be suggested and color & forms of design elements can be proposed.

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THE SPACE-TIME FRACTIONAL DIFFUSION EQUATION WITH CAPUTO DERIVATIVES

  • HUANG F.;LIU F.
    • Journal of applied mathematics & informatics
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    • v.19 no.1_2
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    • pp.179-190
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    • 2005
  • We deal with the Cauchy problem for the space-time fractional diffusion equation, which is obtained from standard diffusion equation by replacing the second-order space derivative with a Caputo (or Riemann-Liouville) derivative of order ${\beta}{\in}$ (0, 2] and the first-order time derivative with Caputo derivative of order ${\beta}{\in}$ (0, 1]. The fundamental solution (Green function) for the Cauchy problem is investigated with respect to its scaling and similarity properties, starting from its Fourier-Laplace representation. We derive explicit expression of the Green function. The Green function also can be interpreted as a spatial probability density function evolving in time. We further explain the similarity property by discussing the scale-invariance of the space-time fractional diffusion equation.

Digital Halftoning with Maze Generation Algorithm (미로 생성 알고리즘을 이용한 디지털 하프토닝)

  • Jho, Cheung-Woon
    • Journal of Advanced Navigation Technology
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    • v.13 no.6
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    • pp.984-990
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    • 2009
  • Halftoning is very important image processing techniques in the digital printing industry which is a process of converting a continuous-tone image to bi-level tone image. In this paper we introduce a new digital halftoning method based on maze generation algorithm as a replacement algorithm of halftoning with space-filling curve. Previous error-diffusion methods based on space-filling curve suffer from regular pattern artifacts from uniform scan pattern. We use maze generation algorithm to remove this undesirable pattern of space-filling curve method.

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On the Relationship Between the Performance Criteria of Unitary Space-Time Codes with Noncoherent and Coherent Decoding

  • Cheun, Kyung-Whoon;Kim, Jeong-Chang;Choi, Soong-Yoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.12A
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    • pp.1145-1151
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    • 2010
  • Hochwald et al. introduced unitary space-time codes for quasi-static Rayleigh fading channels which allows for noncoherent decoding when the channel response is not known at the receiver. However, when reliable information on the channel response is available, coherent decoding is preferable for improved performance. Here, we study the relationship between the performance criteria on the diversity and coding advantages provided by unitary space-time codes with noncoherent and coherent decoding. We show that when a unitary space-time code achieves full spatial diversity with noncoherent decoding, full spatial diversity is also guaranteed with coherent decoding.