• Title/Summary/Keyword: energy space

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A correlation study of substorm injections and ULF power with relativistic electron events

  • Jeong-A Hwang;Gyeong-Uk Min;Ji-Na Lee;Dae-Yeong Lee
    • Bulletin of the Korean Space Science Society
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    • 2004.04a
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    • pp.88-88
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    • 2004
  • We demonstrate that the flux levels of post-storm relativistic electrons are well correlated with the amount of electrons of the energy about 100 keV injected during substorms, while the power of ULF is more or less related to the spectral hardening of these seed electrons. Hence, the existence of ULF alone during the storm time does not necessarily cause flux increase of relativistic electrons as storms do not always generate sufficient amount of seed electrons of this energy range. (omitted)

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Flutter Suppression of Cantilevered Plate Wing using Piezoelectric Materials

  • Makihara, Kanjuro;Onoda, Junjiro;Minesugi, Kenji
    • International Journal of Aeronautical and Space Sciences
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    • v.7 no.2
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    • pp.70-85
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    • 2006
  • The supersonic flutter suppression of a cantilevered plate wing is studied with the finite element method and the quasi-steady aerodynamic theory. We suppress wing flutter by using piezoelectric materials and electric devices. Two approaches to flutter suppression using piezoelectric materials are presented; an energy-recycling semi-active approach and a negative capacitance approach. To assess their flutter suppression performances, we simulate flutter dynamics of the plate wing to which piezoelectric patches are attached. The critical dynamic pressure drastically increases with our flutter control using a negative capacitor.

Energy band structure calculation of crystalline solids using meshfree methods (무요소법을 이8한 결정고체의 에너지 띠 구조 계산)

  • 전석기;임세영
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2002.10a
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    • pp.623-628
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    • 2002
  • A meshfree formulation for the calculation of energy band structure is presented. The conventional meshfree shape function is modified to handle the periodicity of Bravais lattice, and applied to the calculation of real-space electronic-band structure. Numerical examples include the Kronig-Penney model potential and the empirical pseudopotentials of diamond and zinc-blonde semiconductors. Results demonstrate that the meshfree method be a promising one as a real-space technique for the calculations of diverse physical band structures.

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A Study on Non-Linear Matrial and Geomertric Anolysis of Space Truss (기하학적 비선형과 재료적 비선형을 고려한 입체트러스 해석에 관한 연구)

  • 이재문;권영환;김화중
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1990.04a
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    • pp.1-5
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    • 1990
  • The object of this study introducts simple formula being based on energy principle to investigate span truss's non-linear, and considers the relation of member's length, height rate and slenderness ratio to rise prymid truss's economic structure ability through each example. This paper considered space truss's geometric non-linear behavior and material non-linear behavior, so acquired under result through as saying energy principle.

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Coherent Combination of Baryon Acoustic Oscillation Statistics and Peculiar Velocity Measurements from Redshift Survey

  • Song, Yong-Seon
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.46.1-46.1
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    • 2011
  • New statistical method is proposed to coherently combine Baryon Acoustic Oscillation statistics (BAO) and peculiar velocity measurements exploiting decomposed density--density and velocity--velocity spectra in real space from the observed redshift distortions in redshift space, 1) to achieve stronger dark energy constraints, sigma(w)=0.06 and sigma(w_a)=0.20, which are enhanced from BAO or velocity measurements alone, and 2) to cross--check consistency of dark energy constraints from two different approaches; BAO as geometrical measurements and peculiar velocity as large scale structure formation observables.

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Development of P.P.T CanSat System Applying Energy Harvesting System (에너지 하베스팅 시스템을 적용한 자가발전 P.P.T CanSat 시스템 개발)

  • Chae, Bong-Geon;Kim, Su-Hyeon;Kim, Hye-In;Oh, Hyun-Ung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.46 no.4
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    • pp.315-323
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    • 2018
  • CanSat has being attracted considerable attentions for the use as training purposes owing to its advantage that can implement overall system functions of typical commercial satellites within a small package like a beverage can. So-called P.P.T CanSat (Power Plant Trio Can Satellite), proposed in this study, is the name of a CanSat project which have participated in 2015 domestic CanSat competition. Its main objective is to self-power on a LED and a MEMS sensor module by using electrical energy harvested from solar, wind and piezo energy harvesting systems. This study describes the system design results, payload level function tests, flight test results and lessons learned from the flight tests.

DESIGN OF COMPACT PARTICLE DETECTOR SYSTEM USING FPGA FOR SPACE PARTICLE ENVIRONMENT MEASUREMENT (FPGA를 이용한 우주 입자환경 관측용 초소형 입자검출기 시스템 설계)

  • Ryu, K.;Oh, D.S.;Kim, S.J.;Kim, H.J.;Lee, J.J.;Shin, G.H.;Ko, D.H.;Min, K.W.;Hwang, J.A.
    • Journal of Astronomy and Space Sciences
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    • v.24 no.2
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    • pp.155-166
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    • 2007
  • We have designed a high resolution proton and electron telescope for the detection of high energy particles, which constitute a major part of the space environment. The flux of the particles, in the satellite orbits, can vary abruptly according to the position and solar activities. In this study, a conceptual design of the detector, for adapting these variations with a high energy resolution, was made and the performance was estimated. In addition, a parallel processing algorithm was devised and embodied using FPGA for the high speed data processing, capable of detecting high flux without losing energy resolution, on board a satellite.

Towards More Accurate Space-Use Prediction: A Conceptual Framework of an Agent-Based Space-Use Prediction Simulation System

  • Cha, Seung Hyun;Kim, Tae Wan
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.349-352
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    • 2015
  • Size of building has a direct relationship with building cost, energy use and space maintenance cost. Therefore, minimizing building size during a project development is of paramount importance against such wastes. However, incautious reduction of building size may result in crowded space, and therefore harms the functionality despite the fact that building is supposed to satisfactorily support users' activity. A well-balanced design solution is, therefore, needed at an optimum level that minimizes building size in tandem with providing sufficient space to maintain functionality. For such design, architects and engineers need to be informed accurate and reliable space-use information. We present in this paper a conceptual framework of an agent-based space-use prediction simulation system that provides individual level space-use information over time in a building in consideration of project specific user information and activity schedules, space preference, ad beavioural rules. The information will accordingly assist architects and engineers to optimize space of the building as appropriate.

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A Study on Window Type Ventilation System Using IT Technology for Energy Saving in Housing Space (주거공간 내 IT기술 적용 에너지 저감 창호형 환기시스템 연구)

  • Lee, Eun-Hye;Kim, Yong-Seong;Ji, Chung-Gu
    • Journal of the Korean housing association
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    • v.24 no.2
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    • pp.61-68
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    • 2013
  • This study has the purpose to adapt IT technology on Window Type Ventilation System for the energy saving and providing of user-centered comfortable environment. This is Derived a look at the case of the window type ventilation system and researched its IT technology for reducing energy applied to the Green Home. This indicates a solution for the established Window Type Ventilation System which can not be satisfied with user's requirement by proposing Window Type Ventilation System applied to IT technology that makes it control the intelligent, combined indoor environment system and providing information. Also, it shows energy saving efficiency of Window Type Ventilation System applied to IT technology based on the model study, analysing the performance of air-conditioning and ventilation energy saving through the experiment to compare with the established Window Type Ventilation System. The result of this study has the significance that it suggests an alternative for energy saving of housing space.

A Study on the Thermal Characteristics of BIPV Applied on Curtain Wall Spandrel (스팬드럴 적용 BIPV의 후면 열 특성에 관한 연구)

  • Lee, Sang-Gil;Kang, Tae-Woo;Jang, Han-Bin;Kang, Gi-Hwan;Kim, Jun-Tae
    • Journal of the Korean Solar Energy Society
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    • v.32 no.6
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    • pp.120-126
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    • 2012
  • BIPV is applied to buildings in various forms. However, there are some aspects of consideration in applying PV systems in buildings, such as attaching methods, PV electrical efficiency, appearance and so on. BIPV can be installed on curtain wall spandrel as finishing material, which may combine with insulation. The thermal characteristic of spandrel with BIPV has rarely been studied; the temperature of air space between PV module and insulation layer affects both the electrical behavior of PV module and the energy load in a building. This paper aims to analyse the temperature variation of the layers in BIPV spandrels. In this paper, the temperature of layers, including the air space and PV module, was measured for three different type of BIPV applications on spandrel. The results show that the temperature of air layer for the spandrel with G/G(2) type BIPV module on October was the highest among other months.