• Title/Summary/Keyword: Physical Boundary

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In-network Distributed Event Boundary Computation in Wireless Sensor Networks: Challenges, State of the art and Future Directions

  • Jabeen, Farhana;Nawaz, Sarfraz
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권11호
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    • pp.2804-2823
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    • 2013
  • Wireless sensor network (WSN) is a promising technology for monitoring physical phenomena at fine-grained spatial and temporal resolution. However, the typical approach of sending each sensed measurement out of the network for detailed spatial analysis of transient physical phenomena may not be an efficient or scalable solution. This paper focuses on in-network physical phenomena detection schemes, particularly the distributed computation of the boundary of physical phenomena (i.e. event), to support energy efficient spatial analysis in wireless sensor networks. In-network processing approach reduces the amount of network traffic and thus achieves network scalability and lifetime longevity. This study investigates the recent advances in distributed event detection based on in-network processing and includes a concise comparison of various existing schemes. These boundary detection schemes identify not only those sensor nodes that lie on the boundary of the physical phenomena but also the interior nodes. This constitutes an event geometry which is a basic building block of many spatial queries. In this paper, we introduce the challenges and opportunities for research in the field of in-network distributed event geometry boundary detection as well as illustrate the current status of research in this field. We also present new areas where the event geometry boundary detection can be of significant importance.

건축공간구성에 있어서 경계와 영역의 활용에 관한 연구 (A Study on the Application of Boundary and Territory in Aspects of the Spatial Organization of Architecture)

  • 권세훈
    • 한국디지털건축인테리어학회논문집
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    • 제4권1호
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    • pp.10-16
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    • 2004
  • Territory is determined by physical elements that provide the occupants an obvious boundary in a space. The creation of boundary is a interpersonal process by which a person or group regulates interactions with others. The perception of territory needs boundary regulations that mean the composition of horizontal and vertical elements in architectural space. The perception of territory can be defined as perceptual reaction considering not only visual perception on the physical elements in the architectural space and also various kinds of social activity in architectural environment. To achiever territory in architectural space, visible and invisible boundary regulation should be need. It means that territorial boundary regulation needs visual and audial boundary regulation as well as spatial boundary regulation.

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Review of the Hidden Rays of Diffraction

  • Kim, Se-Yun
    • Journal of electromagnetic engineering and science
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    • 제15권1호
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    • pp.1-5
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    • 2015
  • A high-frequency analysis technique, called the hidden rays of diffraction (HRD), is reviewed in this paper. The physical optics and the rigorous diffraction coefficients of a perfectly conducting wedge illuminated by a plane wave are compared. The physical existence of hidden rays on the shadow boundary is explained in view of the geometric theory of diffraction (GTD). In particular, a systematic tracing of hidden rays and its visualization are precisely described by introducing the concept of the supplementary boundary. The physical meaning of the null-field condition in the complementary region is also explained.

사용성 평가 전용 인체모델 선정 소프트웨어 개발 및 자동차 적용사례 (Development Software to Select Boundary Manikins for Product Evaluation: Applied to an Automobile Case)

  • 임영재;박성준;박우진;박준수;정의승;임익성
    • 대한인간공학회지
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    • 제29권6호
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    • pp.831-841
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    • 2010
  • Usability evaluation of physical products involves characterizing complex physical interactions between humans and products. Human models known as manikins have been widely utilized as usability evaluation tools for automobile interior package design. When combined with computer-aided design software programs, such manikins can be used to simulate driving postures and evaluate driver-interior fits early in the design process, and therefore, may greatly facilitate achieving high-quality design in a cost-efficient manner. The purpose of this study was to define a set of manikins for designing automobile interior packages for the South Korean male population. These manikins were conceptualized as "boundary" manikins, which represent individuals lacking in certain physical capacities or having usability-related issues (e.g., an individual with the 5th percentile forward reach capability, an individual with the 95th percentile shoulder width). Such boundary manikins can serve as an efficient tool for determining if an automobile interior design accommodates the majority of the population. The boundary manikins were selected from the large sample of Korean males whose anthropometric dimensions were described in the recent Size Korea anthropometric database. For each male in the database, his comfortable driving posture was represented using a kinematic body linkage model and various physical capacity measured and usability-related characteristics relevant to driver accommodation were evaluated. For each such measure, a boundary manikin was selected among the Korean males. The manikins defined in this study are expected to serve as tools for ergonomic design of automobile interior packages. The manikin selection method developed in this study was implemented as a generic software program useful for various product design applications.

REMOVAL OF HYPERSINGULARITY IN A DIRECT BEM FORMULATION

  • Lee, BongJu
    • Korean Journal of Mathematics
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    • 제18권4호
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    • pp.425-440
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    • 2010
  • Using Green's theorem, elliptic boundary value problems can be converted to boundary integral equations. A numerical methods for boundary integral equations are boundary elementary method(BEM). BEM has advantages over finite element method(FEM) whenever the fundamental solutions are known. Helmholtz type equations arise naturally in many physical applications. In a boundary integral formulation for the exterior Neumann there occurs a hypersingular operator which exhibits a strong singularity like $\frac{1}{|x-y|^3}$ and hence is not an integrable function. In this paper we are going to remove this hypersingularity by reducing the regularity of test functions.

이머시브 공간에서 나타나는 경계성 연구 (A Study on the Boundary Identified in the Immersive Space)

  • 손서연;안성모
    • 한국실내디자인학회논문집
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    • 제27권2호
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    • pp.45-54
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    • 2018
  • Immersive space is a new type of space, which is converged with other domains and expressed in various ways and here, a mutual exchange between space and participants is realized with active intervention of participants. The purpose of this study is to examine boundary changes and characteristics in virtual space and reality or inside and outside, focusing on immersive space. For this study, a case analysis was conducted, based on the key words regarding flow experience and boundary characteristics in immersive space. The boundary characteristics extracted are as follow. First, while immersive space is overlapped in many different ways, the boundary in space gradually changes and one unique and convergent space is formed. Also, a combination of overlap is made with internal and external physical force and a convergent boundary is created. Second, forms are mixed in diverse ways and an unrealistic boundary space is revealed. For new experience, it has familiar, but new experiential characteristics and also shows an expanded boundary by the medium of different domains. Third, a simultaneous space, based on variability of time and space, has an ambiguous boundary due to a meaningless physical boundary of space and changing into a space region constantly, it becomes an unlimited variable space. Fourth, a linear expansion-based emergent space has nonlinearity, which creates a meaningless boundary, recognized as an irregular, dynamic and transformative space and expands to a creative space. In conclusion, it is anticipated that based on diverse characteristics found in immersive space, this study would give unlimited inspiration to many design fields and art creation activities and contribute to a further development through continued research on immersive space.

복수 쿼드로터 무인기를 이용한 협업 감시 및 경계선 추종 (Cooperative Surveillance and Boundary Tracking with Multiple Quadrotor UAVs)

  • 이현범;문성원;김우진;김현진
    • 제어로봇시스템학회논문지
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    • 제19권5호
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    • pp.423-428
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    • 2013
  • This paper investigates a boundary tracking problem using multiple quadrotor UAVs to detect and track the boundary of physical events. We set the boundary estimation problem as a classification problem of the region in which the physical events occur, and employ SVL (Support Vector Learning). We also demonstrate a velocity vector field which is globally attractive to a desired closed path with circulation at the desired speed and a virtual phase for stabilizing the collective configuration of the multiple quadrotors. Experimental results with multiple quadrotors show that this study provides good performance of the collective boundary tracking.

건축 내$\cdot$외부공간 경계의 모호성에 관한 연구 (A Study on the Ambiguity of the Boundary in the Architectural Interior and Exterior Space)

  • 곽기표
    • 한국실내디자인학회논문집
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    • 제14권2호
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    • pp.20-28
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    • 2005
  • This paper investigates that the ambiguity of the boundary between interior space and exterior space in architecture appears universally in history and reveals the various aspects of ambiguous boundary in architecture. The space is formed by the relationship with the surroundings and the boundary of two opposite spaces is apt to be ambiguous according to lots of complex factors. Before Modern Architecture the boundary of interior and exterior space had a tendency to be ambiguous by modifying compositional method of material boundary, that is semi interior-exterior space, the reversion of interior and exterior space and space in space. After Modern Architecture the meaning of physical boundary in space is lost along with dissolution of boundary over the society and the boundary of space comes to be dematerialized by the technology and the change of space perception. The phenomenon of deconstruction in spacial boundary accelerate increasingly according to fluid space, mutually interpenetrated space, visual transparency and adjustment of layers. And contemporary technology is collapsing the meaning itself of space division fundamentally.

평판 경계층 유동조건이 근접후류에 미치는 영향 (Influence of Flow Conditions on a Boundary Layer to the Near-Wake of a Flat Plat)

  • 김동하;장조원
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.1625-1630
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    • 2004
  • An experimental study was carried out to investigate influence of flow conditions on a boundary layer to the near-wake of a flat plate. The flow condition in the vicinity of trailing edge that is influenced by upstream condition history is an essential factor that determines the physical characteristics of a near-wake. Various tripping wires were used to change boundary layer flow condition of upstream at the freestream velocity of 6.0 m/sec. Measurements of the boundary layer and near-wake according to the change of upstream conditions were conducted by using both I-probe(55P14 for boundary layer) and X-probe(55P61 for wake). Normalized velocity profiles of the boundary layer were shown the flow types such as laminar boundary layer, transition, and turbulent boundary layer at 0.95C from the leading edge. The velocity and turbulence intensity profiles of the near-wake for the case of laminar boundary layer at the flat plate surface exhibited a defect and a double peak showing perfect symmetry, respectively.

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경계개념에 의한 아파트 공간구성의 분석 연구 (An Analysis on the Concept of Boundary in Spatial Composition of the Residential Apartments)

  • 이유영;이윤정;정준현
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2008년도 춘계학술발표대회 논문집
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    • pp.311-314
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    • 2008
  • Assuming that while the Confucian idea-based awareness of boundary appeared to have a distinct effect on traditional residential spaces the awareness of an individualized nuclear family-oriented boundary deviated from authoritarianism has been recently shown in the modern residential spaces, this study was conducted to clarify what the modern people's awareness of boundary influences individual residential spaces and how the boundary is structured. This study was carried out by examining prior studies on the concepts of boundary and analysing the planes of residential apartments as a typical modern residential space, based on the comparison of traditional and modern residential spaces. It was shown, then, that the awareness of boundary in the modern residential space appeared to be structured in the residential apartment space according to the change in the social position and role of family members, unlike the spatial division of the traditional residential spaces based on the social class and sex.

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