• Title/Summary/Keyword: distributed targets

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ISAR Imaging of Airplane-like Targets by Matrix Pencil Method (Matrix Pencil 방법에 의한 비행기 모형의 ISAR 영상화)

  • 유지희;권경일;이용희
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.2
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    • pp.299-307
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    • 2001
  • This paper presents a experimental study of Inverse Synthetic Aperture Radar(ISAR) imaging using Matrix Pencil(MP) method. A series of measurement for two types of target model was done in a Compact Range(CR)facility. The first target is a set of distributed slim cylinders to get a ISAR image of point-like scatterers. The second is UAV model representing a complex real target. The results show that ISAR images by MP method are better than by conventional FFT method under the realistic measurement conditions.

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VELOCITY AND ITS DIRECTION MEASUREMENT OF SCATTERER WITH DIFFERENT VELOCITIES USING SELF-MOXING SEMICONDUCTOR LDV

  • Shinohara, Shigenobu;Haneda, Yoshiyuki;Suzuki, Takashi;Ikeda, Hiroaki;Yoshida, Hirofumi;Sawaki, Toshiko;Mito, Keiichiro;Sumi, Masao
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10b
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    • pp.1966-1970
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    • 1991
  • The self-mixing type semiconductor laser Doppler velocimeter(SM-LDV) is applied to measure two simultaneously moving targets with different velocities in the same direction as a prototype target for multiscatterers. The measured beat waveform is found to be a composite wave of each beat waveform measured fran each of only moving target. In the composite waveform, each one-cycle wave has a feature of the sawtooth wave. This fact shows a possibility to discriminate the flow direction of fluid containing multiscatterers with distributed velocities by cooperating an improved version of the direction discrimination circuit already devised by the authors.

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Growth and Physical Characteristics of Crystalline Carbon Nitride Films Using Penning-type Source Sputerring System (페닝 소스 스퍼터링 장치를 이용한 결정성 질화탄소막의 성장 및 물리적 특성)

  • Lee, Sung-Pil;Chowdhury, Shaestagir
    • Journal of Sensor Science and Technology
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    • v.9 no.3
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    • pp.248-255
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    • 2000
  • Penning type sputtering system which has two opposed targets was implemented and the physical characteristics of the deposited carbon nitride films were investigated. When argon ratio was reduced and nitrogen ratio was increased in the sputtering gas mixture, Fe was less sputtered. The grain size of grown carbon nitride films was distributed from $150{\AA}$ to $250{\AA}$. As nitrogen partial pressure increases, growth rate and nitrogen incorporation in the film increases.

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Consumer Analysis for Increasing Occupancy Rates of Tourism Hotel

  • Gozaly, Jimmy
    • Industrial Engineering and Management Systems
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    • v.16 no.1
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    • pp.103-108
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    • 2017
  • Tourism is a sector that plays an important role in the economic growth of Indonesia. Bandung as the capital of West Java province is known as the city with diverse tourism potential, both in the attractiveness of the city and surrounding natural beauty. DHR is a three stars resort hotel in the city with a strategic location. As a three stars resort hotel, DHR has been experiencing occupancy rate problems, consequently, it cannot often reach the set targets, both during high season and low season. The purpose of this study is to identify the factors of hotel performance that influences consumer staying back decision in the future. Questionnaires have been distributed to hotel guests to gather information regarding their interest and the performance assessment of the hotel services and facilities, and staying back decision in the future. Discriminant Analysis and Hypothesis Testing are used to determine which hotel performance variables will directly affect consumer staying back decision. The result of this study provide marketing strategy that should be implemented by the hotel management in order to increase its occupancy rate.

Power Electronics as an Enabling Technology for Renewable Energy Integration

  • Blaabjerg, F.;Chen, Z.
    • Journal of Power Electronics
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    • v.3 no.2
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    • pp.81-89
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    • 2003
  • The global electrical energy consumption is still rising and there is a steady demand to increase the power capacity, to produce, distribute and use the energy as0 efficient as possible and furthermore to set up incentives to save energy at the md-user. Two major technologies will play important roles to fulfill those targets. One is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficiency power electronics in power systems for high efficiency and high performance applications. This paper discusses both areas, in particular the power electronic application in wind power integration.

A Study on the Improvement in Performance of Ultrasonic Pulsed Doppler Velocimeter (초음파 펄스 도플러 속도계의 성능 개선에 관한 연구)

  • 이은방;이상집
    • Journal of the Korean Institute of Navigation
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    • v.20 no.3
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    • pp.85-95
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    • 1996
  • In the velocimeter, the ultrasonic pulse signal is used for measuring the profile velocity of moving targets distributed in space because of the merits of its high distance resolution and harmless affect to the human body. The velocity reading in conventional ultrasonic pulsed velocimeter depends on the wave pattern reflecting the spatial distribution of scatters and includes observational error due to the signal processing of analyzing pulse signal. In this paper, we evaluate an influence of the received waveform of pulsed signal on the velocity information by setting a model. Subsequently, in order to improve the distance resolution and to obtain precise velocity information without the influence of the spatial distribution of scatterers, we propose a new method for the analysis of Doppler pulsed signal, in which the pulsed signal is transformed into a phase function with local data. Finally, it is confirmed that the performance of the velocimeter is more improved in the proposed method than in the conventional one.

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Herschel/SPIRE Galaxies in the NEP-Wide Field - Preliminary Results

  • Kim, Seong Jin;Jeong, Woong-Seob;Lee, Hyung Mok
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.66.3-66.3
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    • 2016
  • We report preliminary results from our analyses on the star-forming galaxies in the Herschel/SPIRE survey data over the AKARI/NEP-Wide Field. In this work, we utilize a combination of the SPIRE point source catalogue containing ~ 4,800 sources distributed over the wide (5.6 sq. deg) field and the spectroscopic redshift (zSPEC) data for 1790 selected targets obtained by MMT/Hectospec and WIYN/Hydra. Our analyses take advantages of multi-wavelengths photometric data (28 bands at most) covering from u* to $500{\mu}m$ band as well as continuous MIR wavelengths sampling by AKARI and WISE (4 to $25{\mu}m$). Various physical properties such as total infrared luminosity (LTIR), star formation rate (SFR), and luminosity functions (LFs) will be presented.

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Imprementation of Real Time HILS System for Ground Test of Underwater Vehicle (수중 운동체의 육상 모의시험을 위한 실시간 HILS 시스템 구현)

  • Park, Yeong-Il;Choi, Young-Chul;Cho, Kyu-Kab;Lee, Man-Hyung
    • Journal of Korean Institute of Industrial Engineers
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    • v.25 no.2
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    • pp.282-289
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    • 1999
  • To minimize a real world test of underwater guided vehicle, it is necessary to perform a test on ground by using closed loop test techniques. This paper describes implementation of HILS(Hardware In the Loop Simulation) system for ground test and test methodologies for performance evaluation of a guided weapon. HILS system uses a real time distributed computer and a real time processing technique. Ground test results of underwater vehicle are presented for moving and stationary targets by using HILS system.

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Bile Acids and the Metabolic Disorders (담즙산과 대사질환)

  • Roh, Ji Hye;Yoon, Jeong-Hyun
    • Korean Journal of Clinical Pharmacy
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    • v.28 no.4
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    • pp.273-278
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    • 2018
  • Bile acids are major constituents of bile and known to help absorb dietary fat and fat-soluble vitamins in the gastrointestinal tract. In the past few decades, many studies have shown that bile acids not only play a role in fat digestion but also function as broad range of signal transduction hormones by binding to various receptors present in cell membranes or nuclei. Bile acid receptors are distributed in a wide range of organs and tissues in the human body. They perform multitudes of physiological functions with complex mechanisms. When bile acids bind to their receptors, they regulate fat and glucose metabolism in a tissue-specific way. In addition, bile acids are shown to inhibit inflammation and fibrosis in the liver. Considering the roles of bile acids as metabolic regulators, bile acids and their receptors can be very attractive targets in treating metabolic disorders. In the future, if roles of bile acids and their receptors are further clarified, they will be the novel target of drugs in the treatment of various metabolic diseases.

A Study on Radar Signal Model for Calculation of RCS Using MUSIC Algorithm (레이더 반사단면적 계산을 위한 레이더 신호모델에 관한 연구)

  • Jeong Junng-Sik;Pang Tian-Ting;Jong Jae-Yong;Kim Chul-Seung;Yang Won-Jae;Ahn Young-Sup
    • Proceedings of KOSOMES biannual meeting
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    • 2005.11a
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    • pp.75-78
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    • 2005
  • The detectability of radar depends on RCS(radar cross section). The RCS for complex radar targets may be only approximately calculated by using low-frequency or high-frequency scattering methods, while the RCS for simple radar targets can be exactly obtained by applying on eigen-function method. However, the conventional methods for calculation of RCS are computationally complex. We propose an radar signal model for RCS calculation by MUSIC algorithm In this research, it is assumed that the radar target is considered as a ring of scatterers. The amplitudes of scatterers may be statistically distributed. As the result, the radar signal model is proposed to use MUSIC, and the RCS is calculated by a simple linear algebraic method.

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