• Title/Summary/Keyword: control period

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Flight Control System Design and Verification Process (비행제어시스템 설계 및 검증 절차)

  • Kim, Chong-Sup
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.8
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    • pp.824-836
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    • 2008
  • Relaxed static stability(RSS) concept has been applied to improve aerodynamic performance of modern version supersonic jet fighter aircraft. Therefore, flight control systems are necessary to stabilize an unstable aircraft, and provides adequate handling qualities and achieve performance enhancements. Standard FCSDVP (Flight Control System Design and Verification Process) is provided to reduce development period of the flight control system. In addition, if this process is employed in developing flight control system, it reduces the trial and error for development and verification of flight control system. This paper addresses the flight control system design and verification process for the RSS aircraft utilizing design goal based on military specifications, linear and nonlinear system design and verification based on universal software, handling quality test based on HILS(Hardware In-the-Loop Simulator) environment, and ground and flight test results to verify aircraft dynamic flight responses.

Position Control of an AC Servo Motor Using Sliding Mode Controller with Disturbance Estimator

  • Jung-Woo;Seung-Bok;Hyun-Jeong;Joon-Ho
    • International Journal of Precision Engineering and Manufacturing
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    • v.5 no.4
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    • pp.14-20
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    • 2004
  • In this work, a new control methodology to achieve accurate position control of an AC servo motor subjected to external disturbance is proposed. Unlike conventional sliding mode controller which requires a prior knowledge of the upper bound of external disturbance, the proposed technique, called sliding mode controller with disturbance estimator (SMCDE), can offer robust control performances without a prior knowledge of the disturbance bound. The SMCDE is featured by an integrated average value of the imposed disturbance over a certain sampling period. By doing this, undesirable chattering phenomenon in the estimation process can be effectively alleviated. The benefits of the proposed control methodology are empirically demonstrated on AC servo motor and control responses are evaluated through a comparative work between the proposed and conventional control schemes.

Biochemical Studies in Relation to Chance of Materials in Process of Growth of Embyro in Silkworm Eggs (Bombyx mori L.) (가잠난 배자발육과정에서 각종내용물질의 변동에 관한 생화학적 연구)

  • 임영우
    • Journal of Sericultural and Entomological Science
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    • v.13 no.1
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    • pp.23-29
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    • 1971
  • As a result of analyzing the change of material substance of all sorts biochemically and comparing the control with ${\gamma}$-ray irradiation (800${\gamma}$, 40 Min), incubating the silkworm eggs (Bombyx mori L.) as the objective in the process of growth of embyro shortly before hatching, the following conclusion has been found. 1. Ascorbic acid has shown the maximum increase of 319 r/g in the Byong B embyro stage and in other words it has increased during the period of vigorous metabolism of the materials in eggs but it has decreased before hatching after that period. 2. Triglyceride has shown the increase of 27.54 mg/g in the Byong A stage, the early period of incubation and in other words it has increased in the period of activation of cells in eggs but it has gradually decreased during the growth of embyro after that period. Great change of either total cholesterol or free cholesterol has not been shown from the early period till shortly before hatching. 3. Free fatty acid has shown the minimum decrease of 257.4$\mu$ mole/g in the Byong A stage in which triglyceride increases greatly. On the contrary, it has shown the increase of 1, 020.0$\mu$ mole/g in Ki A stage in which triglyceride decreases. As a whole, the fact that free fatty acid increases according to the growth of embyro in eggs has been found. 4. Glucose has shown the increase of 281.2 mg/g in control during tile Pigment stage and it has shown the increase of 179.6 mg/g in ${\gamma}$-ray irradiation during the same period. The difference in quantity between the former and the latter is due to the fact that the growth of embyro has been influenced by the radio active. Glucose has changed with free fatty acid and phosphorus the other way round. 5. Control organic phosphorus has shewh the increase of 5.23mg/g during the Byong B or Ki A in which organ and tissue in the emhyro has been formed. Organic phosphorus in ${\gamma}$-ray irradiation has shown the increase of 5.73mg/g during Ki B. Inorganic phosphorus has shown only a little change in the control and ${\gamma}$-ray irradiation. The phosphorus in both has shown a little quantity in the ${\gamma}$-ray irradiation in the early period of incubation. After the Ki A embyro, it has increased rapidly and it has increased till the hatching more continually than in control. The about results of the research will be helpful and instructive to the betterment and improvement, breeding and management of animals and plants.

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The Main Suppressing Factors of Dry Forage Intake in Large-type Goats

  • Thang, Tran Van;Sunagawa, Katsunori;Nagamine, Itsuki;Kishi, Tetsuya;Ogura, Go
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.3
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    • pp.341-352
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    • 2012
  • In large-type goats that were fed on dry forage twice daily, dry forage intake was markedly suppressed after 40 min of feeding had elapsed. The objective of this study was to determine whether or not marked decreases in dry forage intake after 40 min of feeding are mainly caused by the two factors, that is, ruminal distension and increased plasma osmolality induced thirst produced by dry forage feeding. Six large-type male esophageal- and ruminal-fistulated goats (crossbred Japanese Saanen/Nubian, aged 2 to 6 years, weighing $85.1{\pm}4.89kg$) were used in two experiments. The animals were fed ad libitum a diet of roughly crushed alfalfa hay cubes for 2 h from 10:00 to 12:00 am during two experiments. Water was withheld during feeding in both experiments but was available for a period of 30 min after completion of the 2 h feeding period. In experiment 1, saliva lost via the esophageal fistula was replenished by an intraruminal infusion of artificial parotid saliva (RIAPS) in sham feeding conditions (SFC) control, and the treatment was maintained under normal feeding conditions (NFC). In experiment 2, a RIAPS and non-insertion of a balloon (RIAPS-NB) control was conducted in the same manner as the SFC control of experiment 1. The intraruminal infusion of hypertonic solution and insertion of a balloon (RIHS-IB) treatment was carried out simultaneously to reproduce the effects of changing salt content and ruminal distension due to feed entering the rumen. The results of experiment 1 showed that due to the effects of multiple dry forage suppressing factors when feed boluses entered the rumen, eating rates in the NFC treatment decreased (p<0.05) after 40 min of feeding and cumulative dry forage intake for the 2 h feeding period reduced to 43.8% of the SFC control (p<0.01). The results of experiment 2 indicated that due to the two suppressing factors of ruminal distension and increased plasma osmolality induced thirst, eating rates in the RIHS-IB treatment were, as observed under NFC, reduced (p<0.05) and cumulative dry forage intake for the 2 h feeding period decreased to 34.0% of the RIAPS-NB control (p<0.01). The combined effects of ruminal distension and increased plasma osmolality accounted for 77.5% of the suppression of dry forage intake 40 min after the start of dry forage feeding. The results indicate that ruminal distension and increased plasma osmolality induced thirst are the main factors in the suppression of dry forage intake in large-type goats.

Changes in benthic macroinvertebrates communities in response to biological mosquito larvae control techniques (생물학적 모기유충 방제기법 적용에 따른 저서성 대형무척추동물 군집 변동)

  • Han, Jung Soo;An, Chae Hui;Choi, Jun Kil;Lee, Hwang Goo
    • Korean Journal of Environmental Biology
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    • v.37 no.4
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    • pp.600-606
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    • 2019
  • The study site was the camping area in the Hwarang Amusement Park in Danwon-gu, Ansan-si. Study activities were conducted three times a week from July 20, 2018, to August 1, 2018. A control site, natural enemy site, and Bti(Bacillus thuringiensis israelensis) site were selected. The analyses included habitat environment and species composition analyses, community analysis, correlation analysis, and similarity analysis. The water quality analysis found no significant difference in water quality over the study period (p>0.05). A total of 4,818 individuals, 38 species, 22 families, and 11 orders were observed during the study period. The natural enemy site observed during the study period had a similar species composition as the control site. The Bti site differed from other sites by the low number of species and individuals present. According to the community analysis, the natural enemy site was a stable community and the Bti site was an unstable community during the study period. Diptera showed negative associations with temperature and water temperature and mosquito larvae showed significant correlations with temperature and water temperature. The similarity analysis showed that the control site and the natural enemy site were 61.11-73.68% and the Bti site showed 30.77-56.00% similarity.

Effects of the Training of Non-Dominant on Hand Function (과제수행을 통한 비우세손 훈련이 손 기능에 미치는 영향)

  • Jang, Chel;Song, Minok;Kim, Boa;Han, Sujung
    • Journal of The Korean Society of Integrative Medicine
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    • v.3 no.4
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    • pp.1-9
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    • 2015
  • Purpose : We described how the training of non-dominant hand that applicates the activity effects on dominant hand. Method : From November 6th to December 2nd 2013, We randomly selected 18 people that don't have a damage of hand function and are in college of K in Busan. (cross stitch training group 9 people, control group 9 people) All participants agreed on the research after fully being aware of training procedures and spontaneously conducted. Each training was practiced for 40 minutes in once every second day. One researcher deals with three participants at silent environment. We used the study measurement, Purdue pegboard, to investigate the sharpness of hand. To investigate the advancement of hand function caused by cross stitch training, we practiced three times estimations of primary one before training, middle one after 2 weeks training, last one after four weeks training and obtained the following results. Result : First of all, We found that the group of hand training appeared to be advanced of dominant hand's sharpness depending on the training period more than the control group. Second, We found that the group of hand training appeared to be advanced of non-dominant hand's sharpness depending on the training period more than the control group. Third, We found that the group of hand training appeared to be advanced of both hand's sharpness depending on the training period more than the control group. Fourth, We found that the group of hand training appeared to be advanced of the assembling function sharpness depending on the training period more than the control group. Conclusion : Put the results of this research together, we found that non-dominant hand training that used the activity was of help to advance the function of dominant hand. So, we thinks that hand training might help the recovery of affected hand function to the person that have a problem of hand function like hemiplegia patient. It will be required to practice the further study targeting the person that have a problem of hand function like hemiplegia patient. We hope that this research will be apply to clinical occupational therapy.

Effect of UV-C and Electron Beam Irradiation of on the Quality of Rice Wine (Makgeolli) (UV-C 및 전자선 조사가 막걸리의 품질에 미치는 영향)

  • Kim, Hyun-Joo;Lee, Kyung Haeng;Yong, Hae In;Jo, Cheorun
    • Food Science and Preservation
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    • v.20 no.1
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    • pp.45-51
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    • 2013
  • This study was conducted to evaluate the changes in the quality of rice wine (Makgeolli) treated with UV-C and electron beam (EB) irradiation during its storage at $4^{\circ}C$ for 15 days. The EB irradiation was found to be more effective than the UV-C irradiation for microbiological control. The pH tended to be increased by UV-C, EB irradiation, and storage period. Acidity was significantly higher in rice wine treated with EB irradiation than those of control and UV-C irradiation during storage period. The $L^*$-value of the samples treated with UV-C and EB irradiation tended to be proportionately higher than that of the control, but this was not consistent during storage period. The $a^*$-value of the sample treated with EB was higher than that of the others, but this was not consistent during the storage period. The reducing sugar content was higher in the control at day 0, but it rapidly decreased compared with the control during the storage. The results indicate that EB irradiation was more effective than UV-C irradiation in controlling microorganisms of rice wine. However, a further study is needed to minimize the rice wine quality deterioration caused by UV-C or EB irradiation during storage.

Improvement of Low Speed Characteristics in Induction Motor Drives by Reduced Order Torque Observer (감소차원 토크관측기를 이용한 유도전동기의 저속운전특성 개선)

  • 유영석;윤덕용;홍순찬
    • Proceedings of the KIPE Conference
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    • 1997.07a
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    • pp.177-181
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    • 1997
  • In the speed control system of motors using the low resolution rotary encoder, the period of encoder pulse becomes longer than the sampling time for speed control in the range of very low speed. Therefore, it is difficult to obtain accurate speed information. In this paper, the speed estimating method at the very low speed region using reduced order torque observer, which has been widely used, is examined. The results of simulation show that the characteristics of the speed control at the very low speed region is improved by using the reduced order torque observer.

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Single Sensor Current Control for Three-Phase Voltage-Source PWM Converters Using a Predictive State Observer (예측 상태 관측기를 이용한 3상 전압 원 PWM 컨버터의 단일 센서 전류 제어)

  • 이우철;현동석;이택기
    • Proceedings of the KIPE Conference
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    • 1999.07a
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    • pp.489-492
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    • 1999
  • This paper proposes a control method for three-phase voltage-source PWM converters using only a single current sensor in the DC link. A predictive current controller for the voltage-source PWM converter is used so that all phase currents can be reconstructed in a switching period although one or two of active vectors are applied only for a short time. Compensation of the 2 step delays is also included. In this paper single sensor current control using predictive state observer will be discussed, and investigated experimentally.

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Contruction of a robust control system for a plant with time delay

  • Morikawa, Youichi;Kamiya, Yuji
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.103-105
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    • 1995
  • In this paper, though Simith controller is also used, we propose a new system configuration which can be regarded an SISO continuous nth-order plant with time delay of k-times of a sampling period as a linear discrete (n + k)th order plant of which all state variables can be available. Consequently, we can pply linear control system design techniques which do not consider the existence of time delay to the proposed system.

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