• 제목/요약/키워드: Change Rate

Search Result 9,316, Processing Time 0.039 seconds

Spacecraft Spin Rate Change due to Propellant Redistribution Between Tanks

  • Choi, Kyu-Hong
    • Journal of Astronomy and Space Sciences
    • /
    • v.1 no.1
    • /
    • pp.23-34
    • /
    • 1984
  • A bubble trapped in the liquid manifold of INTELSAT IV F-7 spacecraft caused a mass imbalance between the System 1 propellant tanks and a wobble half angle of 0.38 degree to 0.48 degree. A maneuver on May 14, 1980 passed the bubble through the axial jet and allowed propellant to redistribute. A 0.2 rpm change in sin rate was observed with an exponential decay time constant of 6 minutes. In this paper, moment of inertia, tank geometry and hydrodynamic models are derived to match the observed spin rate data. The values of the total mass of propellant considered were 16, 19 and 20 kgs with corresponding mass imbalances of 14.3, 15 and 15.1 Kgs, respectively. The result shows excellent agreement with observed spin rate data but it was necessary to assume a greater mass of hydrazine in the tanks than propellant accounting indicated.

  • PDF

The Effect of Perceived Justice on Customer Satisfaction and Repuchase Intention in the Discount Stores Service Recovery (할인점 서비스 회복과정의 공정성 지각이 고객만족과 재구매 의도에 미치는 영향)

  • Kim, Yong-han;Bae, Mu-eun
    • Journal of Distribution Science
    • /
    • v.3 no.1
    • /
    • pp.23-42
    • /
    • 2005
  • The service offer expectation and the desire of customers to a large-sized rate influence store also increase as a result of such environmental change. the counter where research of a book was upgraded from differentiation pursuit by competition between business condition in business condition in the case of the domestic rate influence store which has put the focus on service strengthening The work shrine which cannot reach here the competition predominance in the domestic market it will be hard coming to secure, when environmental change of inside large-sized rate influence store industry is taken into consideration The research which tried to receive customer service failure recovery carried out actual proof analysis in the influence to which fair nature lateness of a customer attains to the re-purchase intention to this store of customer satisfaction and future by service recovery process for an object in the customer who held service failure recovery experience in the domestic large-sized rate influence store.

  • PDF

Compensation for the Body-Coupling in the 2-Gimballed Seeker Homing Loop on BTT Missile

  • Sangkeun Jeong;Kim, Eulgon;Chanho Song;Hangju Cho
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.156.1-156
    • /
    • 2001
  • It is observed that if the 2-gimballed seeker is stabilized using rate gyros mounted along its primary axis, line of sight change measured in the seeker is induced by the rolling due to the bank-to-turn(BTT) steering as well as the actual change. This body-coupling within BTT homing includes the spurious target maneuver effect and the coupling loop due to the rate gyro misalignment. In this paper we formulates the linear BTT homing loop model with a 2-gimballed seeker including those body-coupling effects. With the model, we analyze the effects of the couplings, and show that the roll rate coupling to the rate gyro for the stabilztion of gimbal could seriously deteriorate the homing loop stability. And we propose a direct linear compensator for the coupling to recover the stability.

  • PDF

Testing the exchange rate data for the parameter change based on ARMA-GARCH model

  • Song, Junmo;Ko, Bangwon
    • Journal of the Korean Data and Information Science Society
    • /
    • v.24 no.6
    • /
    • pp.1551-1559
    • /
    • 2013
  • In this paper, we analyze the Korean Won/Japanese 100 Yen exchange rate data based on the ARMA-GARCH model, and perform the test for detecting the parameter changes. As a test statistics, we employ the cumulative sum (CUSUM) test for ARMA-GARCH model, which is introduced by Lee and Song (2008). Our empirical analysis indicates that the KRW/JPY exchange rate series experienced several parameter changes during the period from January 2000 to December 2012, which leads to a fitting of AR-IGARCH model to the whole series.

Pullulan Production and Morphological Change of Aureobasidium pullulans ATCC 9348 (Aureobasidium pullulans ATCC 9348의 Pullulan 생산과 균체 형태의 변화)

  • Kwon, Oh-Sung;Nam, Hee-Sop;Lee, Hyung-Jae;Shin, Yong-Chul
    • Microbiology and Biotechnology Letters
    • /
    • v.22 no.6
    • /
    • pp.565-570
    • /
    • 1994
  • The pullulan production and morphological change of Aureobasidium pullulans ATCC 9348 were investigated both in batch fermentation and in continuous fermentation. The best carbon source for pullulan production was sucrose among seven different carbon sources. The pullulan production of A. pullulans was increased with increasing the carbon to nitrogen ratio of the medium using sucrose as a carbon source. In batch fermentation, production of pullullan occurred following exhaustion of the nitrogen source from the medium. The continuous fermentation showed that the pullulan production was closely parallelled with cell growth and was most effective at a dilution rate of 0.06~0.07 hr$^{-1}$-. The ratio of yeast-like cells(blastospores) of A. pullulans increased with the increase of growth rate, and reached 100% over the growth rate of 0.07 hr$^{-1}$. The growth rate, within a certain range, affected not only on the cell morphology, but on the specific pullulan productivity of A. pullulans.

  • PDF

Effects of Work-Hardening Exponent and Strain-Rate Hardening Exponent on the Determination of Friction Factor (가공경화지수 및 변형율속도 경화지수의 변화가 마찰상수 결정에 미치는 영향)

  • Park, C.Y.;Yang, D.Y.
    • Transactions of Materials Processing
    • /
    • v.1 no.1
    • /
    • pp.42-51
    • /
    • 1992
  • The ring compression test has been widely employed as an experimental means to determine the friction factor. The calibration curves are obtained by the rigid-plastic finite element analysis for various work-hardening exponent and strain-rate hardening exponent. The effects of work-hardening exponent and strain-rate hardening exponent are thoroughly studied and discussed from the finite element computation. The change of friction factor during height reduction in ring compression is also discussed. Then, the method to estimate the change of friction factor during ring compression is proposed.

  • PDF

The Noise Effect on Stuttering and Overall Speech Rate: Multi-talker Babble Noise (다화자잡음이 말더듬의 비율과 말속도에 미치는 영향)

  • Park, Jin;Chung, In-Kie
    • Phonetics and Speech Sciences
    • /
    • v.4 no.2
    • /
    • pp.121-126
    • /
    • 2012
  • This study deals with how stuttering changes in its frequency in a situation where adult participants who stutter are exposed to one type of background noise, that is, multi-talker babble noise. Eight American English-speaking adults who stutter participated in this study. Each of the subjects read aloud sentences under each of three speaking conditions (i.e., typical solo reading (TSR), typical choral reading (TCR), and multi-talker babble noise reading (BNR)). Speech fluency was computed based on a percentage of syllables stuttered (%SS) and speaking rate was also assessed to examine if there was significant change in rates as a measure of vocal change under each of the speaking conditions. The study found that participants read more fluently both during BNR and during TCR than during TSR. The study also found that participants did not show significant changes in speaking rate across the three speaking conditions. Some discussion was provided in relation to the effect of multi-talker babble noise on the frequency of stuttering and its further speculation.

A Study on the Dosage ate Control of the Pre-Chorine in Water Purification using Fuzzy Inference Technique (퍼지 론기법 정수공정의 전염소주입율 제어에 관한 연구)

  • 이상석;소명옥;이준탁
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.2 no.1
    • /
    • pp.89-95
    • /
    • 1996
  • This paper describes a fuzzy controlled pre-chlorination technique for purifying the pulluted raw water in water purification lants. For the purpose of obtaining the high quality water, the appropriate pre-chlorine dosage rate has to be continuously adjusted according to a change in quality of a intake raw water, weather, solar nergy mount, temperature and etc. Therefore, the method of expressing an expert's empirical knowledge cumulated from his past carrier by fuzzy reasoning and the fuzzy controller design technique is necessary.In this paper fuzzy membership functions and rules accordingto emprircal knowledge and experimental field data were obtained, And also fuzzy cintriller design using four feedforward components for the determination of pre-chlorine dosage rate and four feedback ones for the compensation of its dosage rate with residual chlorine and its change rate, was executed.

  • PDF

A Study on Analysis of Disturbance in VLC Transceiver Module Based on LED Communication (LED 조명통신용 드라이빙기술 기반 VLC 송수신기 모듈의 외란광 분석에 관한 연구)

  • Hong, Geun-Bin;Jang, Tae-Su;Kim, Tae-Hyung;Kim, Yong-Kab
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.60 no.7
    • /
    • pp.1391-1395
    • /
    • 2011
  • In this paper, would implement a transceiver for the visible light communication that based on wireless communication driving technology for LED illumination-based infrared ray communication, and measurement analyzed a design error rate of a transceiver variable rate has made about distance change -2.5m. The error rate measured a voltage variable along illuminate change between switchable circumstances, which has illuminated insight and outright. Each analyzed and measurement on the communication distance errors along the differences of disturbance light between night and days. The LED module has implemented for number of 6 through illumination dimming in case of different values. Also, implementation for the system module of a VLC transceiver based on the infrared sensors which used feedback outcome value has analyzed with error rate.

Plating Rate of Electroless Nikel-Copper-Phosphorus Plating and Change in Microhardness and Corrosion Rate depending on. Heat treatment (무전해 니켈-구리-인 도금의 도금속도와 열처리에 따른 경도 및 내삭성 변화)

  • 오이식;황용길
    • Journal of the Korean institute of surface engineering
    • /
    • v.23 no.4
    • /
    • pp.208-217
    • /
    • 1990
  • Electroless Ni-Cu-P plating was performed was performed to investigate for plating and changes in microhardness and corrosion rate of of electroless deposits depending on heat treatment. The activation energy for $75~85^{\circ}C$ were calculated to be 66.7KJ/mole. Plating rate increased to 34% with addition of 200ppm of NaF and 0.8ppm of thiourea to the bath. The highest hardness value was obtained by heat treatment deposits layer at$ 400^{\circ}C$, 1 hour. The increase in hardness of deposits by heating was confirmed to be associated with crystallization of the amorphous deposits. Corrosion resistance of deposir layer, which had been heated up to $300^{\circ}C$, was found to be exellent when immersed in 1N-H2SO4 solution, Change of the corrosion resistance seems to have some important bearing on content of amorpous, Ni3P and Cu3P.

  • PDF