• 제목/요약/키워드: Impulse performance

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Empirical Study of Dynamic Chinese Corporate Governance Based on Chinese-listed Firms with A Panel VAR Approach

  • Shao, Lin;Zhang, Li;Yu, Xiaohong
    • The Journal of Industrial Distribution & Business
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    • v.8 no.1
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    • pp.5-13
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    • 2017
  • Purpose - In this article, a dynamic model like a VAR is an appropriate choice for estimating the possible interrelationship between ownership structure and firm performance as a dynamic process. Research design, data, and methodology - Data of this work are collected from Chinese stock exchange including 350 Chinese-listed firms during the period of 1999-2012. We hypothesize that this interrelationship dynamically exists between ownership structure and firm performance. To examine the correlation, a panel Vector Auto-regression (PVAR) approach generated by GMM method is utilized to test the possible dynamic relation embedded in corporate governance. Another two dynamic analysis solutions such as orthogonalized impulse-response function and variance decomposition are also used simultaneously. Results - Findings of this study indicate the evidence that dynamically endogenous relationship exists between ownership structure and firm performance. Further, there is a dynamical correlation between investment and performance. Impulse response and variance decomposition illustrate that impact of a shock to variables themselves is the main source for their variability. Conclusions - The conclusion in this study is that there is a bidirectional and inter-temporal effect between proportion of ownership and corporate performance for a long run in accordance with impulse response function. Overall, our results suggest that corporate governance in China is more market oriented.

Study on the Chirped Waveform of the USPR Pulse using the Impulse Response of a Waveguide

  • Roh, Young-Su
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.3
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    • pp.20-26
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    • 2010
  • In ultrashort-pulse reflectometry (USPR), a chirped waveform transformed from the USPR source impulse signal via waveguide makes it possible to employ millimeter-wave mixers for the frequency up-conversion process. Consequently, the frequency bandwidth of the USPR system is sufficiently wide to cover a large portion of the electron density profile of the plasma. Some physical aspects of the chirped waveform, such as maximum amplitude and length, are critical factors to determine the performance of the system. In this paper, the propagation of the USPR impulse signal through a rectangular waveguide is numerically studied to derive the chirped waveform using the impulse response of the waveguide. The results of numerical computation show that the chirped waveform significantly depends on the waveguide cutoff frequency as well as the waveguide length.

A study on the Buying Intention and Impulse Buying of Discount Store Apparel (할인점 의류제품의 구매의도와 충동구매에 관한 연구)

  • 정영주;장은영;이선재
    • Journal of the Korean Society of Costume
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    • v.52 no.1
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    • pp.37-52
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    • 2002
  • The purpose of this study was to investigate influential factors on the buying intention and the impulse buying of discount store apparel. Data were collected by randomly surveys and the subject was married women. SPSS PC+8.0 was used to analyze the data. The factors to influence on the buying intention of discount store apparel were perceived money value, store image, brand familarity, differentiated needs, perceived risk, perceived quality, voluntary performance. It was found that perceived money value affected buying intension and that perceived quality affected the satisfaction after buying. The factors to influence on impulse buying of discount store apparel were environmental stimulus, useful stimulus, emotional stimulus, situational stimulus of consumer. The relationship between factors of impulse buying and influenced factors of buying intention was that store image affected useful stimulus and differentiated needs affected emotional stimulus.

Effect of Combustion Chamber Pressure to Specific Impulse of Liquid Rocket Engine (액체로켓엔진에서 연소압이 비추력에 미치는 영향)

  • Cho, Won-Kook;Park, Soon-Young;Seol, Woo-Seok
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.3154-3158
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    • 2008
  • A liquid rocket engine performance has been analyzed as a function of combustion pressure with LOx/RP-1R. The present method is verified by comparing the specific impulse for various combustion pressure with given pump head model. The optimal combustion pressure is between 150 bar and 200 bar for given efficiencies. Both the optimal combustion pressure and the specific impulse increase for increased turbine efficiency. The optimal combustion pressure decreases and the specific impulse increases for increased combustion efficiency. The pump efficiency and the turbine inlet temperature have the same qualitative effect as the turbine efficiency.

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A Study on the step response characteristics in shielded resistor divider for full lightning impulse voltage (전파 뇌충격전압 측정용 쉴드저항분압기의 직각파 특성에 관한 연구)

  • 김익수;이형호;조정수;박정후
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.45 no.2
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    • pp.283-288
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    • 1996
  • This paper presents the development technology of standard shielded resistor divider for full lightning impulse voltage. The ability of large-capacity power apparatus to withstand lighting stroke is usually evaluated by means of full lightning impulse voltage. Lightning impulse voltage test has been essential to evaluate the insulation performance of electrical power apparatus. Recently international standard (IEC 60) on high voltage measurement techniques is being revised and requests a formal traceability of high voltage measurements. Therefore, general interest for this area has grown considerably during last years, and several international intercomparisons have already completed worldwide, i.e. Europe, Japan, America etc., In this viewpoint, we have also investigated the step response of the standard shielded resistor divider, which satisfies the IEC recommendation.

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Edge Impulse Machine Learning for Embedded System Design (Edge Impulse 기계 학습 기반의 임베디드 시스템 설계)

  • Hong, Seon Hack
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.17 no.3
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    • pp.9-15
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    • 2021
  • In this paper, the Embedded MEMS system to the power apparatus used Edge Impulse machine learning tools and therefore an improved predictive system design is implemented. The proposed MEMS embedded system is developed based on nRF52840 system and the sensor with 3-Axis Digital Magnetometer, I2C interface and magnetic measurable range ±120 uT, BM1422AGMV which incorporates magneto impedance elements to detect magnetic field and the ARM M4 32-bit processor controller circuit in a small package. The MEMS embedded platform is consisted with Edge Impulse Machine Learning and system driver implementation between hardware and software drivers using SensorQ which is special queue including user application temporary sensor data. In this paper by experimenting, TensorFlow machine learning training output is applied to the power apparatus for analyzing the status such as "Normal, Warning, Hazard" and predicting the performance at level of 99.6% accuracy and 0.01 loss.

A 3-Dimensional Numerical Simulation of Impulse Turbine for Wave Energy Conversion

  • Lee, Hyeong-Gu;Lee, Yeon-Won
    • Journal of Advanced Marine Engineering and Technology
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    • v.27 no.4
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    • pp.535-541
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    • 2003
  • This paper describes numerical analysis of the impulse turbine with fixed guide vanes, a high performance hi-directional air turbine having simple structure for wane energy conversion. A 3-dimensional incompressible viscous flow numerical analysis based on the full Reynolds-averaged Wavier-Stokes equations was made to investigate the internal flow behavior Numerical results ate compared with experimental data. As a result, a suitable choice for the one of design factors has been clarified.

Test & Evaluation for the Configuration Optimization of Thrust Chamber in 70 N-class N2H4 Thruster (Part I: Pulse-mode Performance According to the Chamber Diameter Variation) (70 N급 하이드라진 추력기의 추력실 최적설계와 시험평가 (Part I: 추력실 직경변화에 따른 펄스모드 성능특성))

  • Kim, Jong Hyun;Jung, Hun;Kim, Jeong Soo
    • Journal of the Korean Society of Propulsion Engineers
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    • v.18 no.1
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    • pp.42-49
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    • 2014
  • Performance evaluation was carried out for the 70 N-class hydrazine thruster whose design performance had been already verified. The pulse-mode firing test was conducted for the development model thrusters with various thrust chamber diameters. Evaluation was made by the performance parameters such as specific impulse, impulse bit, and characteristic velocity, etc: specific impulse and characteristic velocity were deteriorated as the thrust chamber diameter deviates from a standard model. Consequently, it is revealed that the performance characteristics of standard model is most superior among the test models.

Performance Analysis of Interleaved Super Orthogonal Convolutional Coded UWB-IR System for Wireless Fading Environment (무선 페이딩 환경에 적합한 인터리브된 초직교 길쌈 부호화 UWB-IR 시스템의 성능 분석)

  • Kim Chang-Joong;Lee Ho-Kyoung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.6 s.97
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    • pp.556-562
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    • 2005
  • In this paper, we propose interleaved super-orthogonal convolutional coded ultra wide-band impulse radio(ISOC-UWB-IR) system, and analyze its performance. The proposed system uses interleaver and deinterleaver to decorrelate the temporal correlation of the fading process and to obtain the diversity gain. We also suggest the three types of interleavers, which are pulse-wise interleaver(PI), pulse sub-group-wise interleaver(PSGI), and pulse group-wise interleaver(PGI). Performance analysis result shows that the interleaving scheme, rather than the code rate of super orthogonal convolutional code(SOC) encoder, affects the performance for the Rayleigh fading channel.

Performance Evaluation of Time Hopping Binary PPM Impulse Radio System according to Interference Environment (간섭 환경에 따른 TH Binary PPM IR 시스템의 성능 평가)

  • Lee, Yang-Sun;Kang, Heau-Jo
    • Journal of Advanced Navigation Technology
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    • v.6 no.4
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    • pp.318-325
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    • 2002
  • In this paper, the effects of the interference environments on the performance of the time hopping(TH) binary PPM impulse radio(IR) system are presented. Based on the monocycle pulse available within the frequency of 3.1~10.6 GHz permitted for application by FCC, a PPM-modulated TH IR system simulator was designed and followed by the analysis of the monocycle pulse characteristics as well as the system performance. Particularly for the evaluation of the system performance, the multiple access interference and the narrowband system interference signals were considered as the interference signals. Since the narrowband system interference signal has very narrow bandwidth and very large amplitude compared with those of IR system, the analysis of the IR system performance was implemented by considering the interference power and band fraction ratio of the narrowband interference signal.

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