• 제목/요약/키워드: Data Disturbance

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머시닝센터 장착형 2축 연마 로봇의 성능평가 (The Evaluation of Performance of 2-Axis Polishing Robot Attached to Machining Center)

  • 박준혁
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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    • pp.411-416
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    • 2000
  • Cutting process has been automated by progress of CNC and CAD/CAM, but polishing process has been depended on only experiential knowledge of expert. To automate the polishing process, a polishing robot with w degrees of freedom which is attached to a machining center with 3 degrees of freedom has been developed. This automatic polishing robot is able to keep the polishing tool normal on the curved surface of die to improve a performance of polishing. Polishing task for a curved surface die demands repetitive operation and high precision, but conventional control algorithm can not cope with the problem of disturbance such as a change of load. In this research, a new sliding mode control algorithm is applied to the robot. The signal compression method is used to identify polishing robot system. to obtain an effect of 5 degrees of freedom motion, a synchronization between the machining center and polishing robot is accomplished by using M code of machining center. And also a trajectory for polishing the curved surface die by 5 degrees of freedom motion, a synchronization between the machining center and polishing robot is accomplished by using M code of machining center. And also a trajectory for polishing the curved surface die by 5 axes machining center is divided into data of two types for 3 axes machining center and 2 axes polishing robot. To evaluate polishing performance of the robot. various experiments are carried out.

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간호제공자들의 치매노인 공격행동 경험에 대한 연구 (The Experience of Nursing Staff on the Dementia Patients′ Aggressive Behavior)

  • 오진주
    • 대한간호학회지
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    • 제30권2호
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    • pp.293-306
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    • 2000
  • Providing care to the dementia elderly with behavioral problem is a major issue in nursing homes today. This study was aimed to explore the nursing staffs′ response to aggressive dementia patients, and the effect that the aggressive behavior had on Nsgstaff. The interviews used a semi-structured questionnaire are were carried out from May to July, 1999. The subjects were 23 nursing personnel working in the nursing homes for dementia elderly. The result are as follows; 1. The types of aggressive behavior cited by the subjects was "physical", "linguistic", and "sexual". 2. The factors that caused the behavior were "symptoms of disease", "under- conditioning", "context of nursing care", "unsatisfied need", "relationship to other patients", "change of outer environment", and "invasion of one′s own privacy". 3. The response of the subjects were "unhappiness", "stress", "anger", "exaggeration", "anxiety", and "fear". 4. The management strategies listed by nursing personnel used to alleviate aggressive behavior were "ignorance" "patience" "leaving the area" "soothing sounds" "verbal punishment" "restriction and isolation" and "various management skill appliance" "adaptation". 5. The effect that aggressive behavior and were "disturbance of relationship to elderly" "decline in the amount and quality of nursing care" "interruption of task performance" "job exhaustion" "desire to leave the job" "physical impact" "stress on the cognition of others" "anxiety about health and one own future" "interference to family life′. The findings of this study will be useful in understanding the difficulties of nursing personnel when confronting the aggressive behavior of dementia partients. It also is useful as basic data in preparing efficient intervention program for these difficulties.

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RLSM을 이용한 안구운동의 저속도 측정방법에 대한 연구 (A Method for Slow Component Velocity Measurement of Nystagmus Eye Movements using RLSM)

  • 김규겸;고종선;박병림
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2002년도 전력전자학술대회 논문집
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    • pp.455-458
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    • 2002
  • A control of the body posture and movement is maintained by the vestibular system, vision, and proprioceptors. Especially, vestibular system has a very important function that controls the eye movement through vestibuloocular reflex and contraction of skeletal muscles through vestibulospinal reflex. However, postural disturbance caused by loss of vestibular function results in nausea, vomiting, vertigo and loss of craving for life. Lose of vestibular function leads to abnormal reflex of eye movements named nystagmus. Analysis of the nystagmus is needed to diagnose the vertigo, which is performed by means of electronystagmography (ENG). The purpose of this study is to develop a computerized system for data processing and an algorithm for the automatic evaluation of the slow component velocity (SCV) of nystagmus Induced by optokinetic(OKN) stimulation system. A new algorithm using recursive least square method (RLSM) to detect SCV of nystagmus is suggested in this paper. This method allows a fast and precise evaluation of the nystagmus, through artifact rejection techniques. The results are depicted in this paper.

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Design Of Fuzzy Controller for the Steam Temperature Process in the Coal Fired Power Plant

  • Shin, Sang Doo;Kim, Yi-Gon;Lee, Bong Kuk;Bae, Young Chul
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제4권2호
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    • pp.187-192
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    • 2004
  • In this paper, we proposed the method to design fuzzy controller using the experience of the operating expert and experimental numeric data for the robust control about the noise and disturbance instead of the traditional PID controller for the main steam temperature control of the thermal power plant. The temperature of main steam temperature process has to be controlled uniformly for the stable electric power output. The process has the problem of the hunting for the cases of various disturbances. In that case, the manual action of the operator happened to be introduced in some cases. We adopted the TSK (Takagi-Sugeno-Kang) model as the fuzzy controller and designed the fuzzy rules using the informations extracted directly from the real plant and various operating condition to solve the above problems and to apply practically. We implemented the real fuzzy controller as the Function Block module in the DCS(Distributed Control System) and evaluated the feasibility through the experimental results of the simulation.

Overlay Multicast Update Strategy Based on Perturbation Theory

  • Shen, Ye;Feng, Jing;Ma, Weijun;Jiang, Lei;Yin, Min
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권1호
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    • pp.171-192
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    • 2017
  • The change of any element in the network is possible to cause performance degradation of the multicast network. So it is necessary to optimize the topology path through the multicast update strategy, which directly affects the performance and user experience of the overlay multicast. In view of the above, a new multicast tree update strategy based on perturbation theory Musp (Multicast Update Strategy based on Perturbation theory) is proposed, which reduces the data transmission interruption caused by the multicast tree update and improves user experiences. According to the multicast tree's elements performance and the topology structure, the Musp strategy defines the multicast metric matrix and based on the matrix perturbation theory it also defines the multicast fluctuation factor. Besides it also demonstrates the calculability of the multicast fluctuation factor presents the steps of the Musp algorithm and calculates the complexity. The experimental results show that compared with other update strategies, as for the sensitivity of the multicast fluctuation factor's energized multicast tree to the network disturbance, the maximum delay of the Musp update strategy is minimal in the case of the local degradation of network performance.

수도작 포장의 고저차 분석 (Variation Analysis of Elevation within a Rice Paddy Field)

  • 성제훈;장순우
    • Journal of Biosystems Engineering
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    • 제31권3호
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    • pp.188-193
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    • 2006
  • Elevation differences within a paddy field relate strongly to plant health, crop homogeneity, and pest control. For precision agriculture (PA), the elevation within a field should be precisely controlled. We analyzed variation in elevation within a rice paddy field over one crop cycle. The study took place in a rectangular plot (100 m x 30 m). Elevations within the a plots was measured by a laser-equipped surveying instrument, that could determine elevations to precisions of I mm. The test field was divided into grids with 30 squares; elevation was measured at the center of each 5 x 10-m grid square. This study measured elevation during nine observation periods from pre-plowing to post-harvest. Descriptive statistics showed the highest elevations after plowing due to soil disturbance. One-way analysis of variance (ANOVA) revealed significant elevation differences before and after plowing and transplanting, although elevations were similar over the period of crop growth. Comparison of pre-plowing and post-harvest data showed differences in elevations, indicating that elevation changes occurred during plowing, rice transplanting, plant growth, and harvesting. In summary, the above statistical analysis indicated that elevation changes occurred due to plowing but not during the plant growth season or due to harvesting.

Efficient Time Domain Aeroelastic Analysis Using System Identification

  • Kwon, Hyuk-Jun;Kim, Jong-Yun;Lee, In;Kim, Dong-Hyun
    • International Journal of Aeronautical and Space Sciences
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    • 제6권1호
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    • pp.52-60
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    • 2005
  • The CFD coupled aeroelastic analyses have significant advantages over linear panel methods in their accuracy and usefulness for the simulation of actual aeroelastic motion after specific initial disturbance. However, in spite of their advantages, a heavy computation time is required. In this paper, a method is discussed to save a computational cost in the time domain aeroelastic analysis based on the system identification technique. The coefficients of system identification model are fit to the computed time response obtained from a previously developed aeroelastic analysis code. Because the non-dimensionalized data is only used to construct the model structure, the resulting model of the unsteady CFD solution is independent of dynamic pressure and this independency makes it possible to find the flutter dynamic pressure without the unsteady aerodynamic computation. To confirm the accuracy of the system identification methodology, the system model responses are compared with those of the CFD coupled aeroelastic analysis at the same dynamic pressure.

Study of Short-Term Sunspot Motion toward Flare Onset Prediction

  • Suematsu, Yoshinori;Yatini, Clara Y.
    • 천문학회보
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    • 제36권2호
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    • pp.87.2-87.2
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    • 2011
  • Proper motion of sunspots in several active regions was studied to detect their indicator on flare onset, using data from the Solar Flare Telescope at Mitaka (four flaring active regions), TRACE (e.g. NOAA 0424, M1.7 flare on 5 Aug. 2003) and Hinode (e.g. NOAA 10930, X3.4 flare on 13 Dec. 2006). The proper motion of individual sunspots was derived using a local correlation tracking method. As a result, we found that the sunspots that are located under or close to a part of chromospheric flaring patches showed a change in their moving direction prior to the flare onset. The change in their movements took place a half to two hours before the flare onset. On the other hand, sunspots in non-flaring areas or non-flaring active regions did not show this kind of change. It is likely, therefore, that if a sunspot shows the particular movement, a chromospheric flare is to occur in its nearby region. In the most active regions, the part of flare ribbons was located on an emerging bipolar pair of sunspots. The disturbance in the usual motion of the bipolar sunspots and in other sunspots as well can be interpreted as a sign of magnetic shear development leading to final magnetic energy buildup before its sudden release. We suggest that the change in sunspot motion in a short time scale prior to the flare onset can be regarded as a good indicator in predicting the onset timing and location of chromospheric flares.

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FES를 이용한 편마비 환자의 보행증진에 대한 연구 (Study for gait improvement of hemiplegic patients using Functional Electrical Stimulation)

  • 양회송;김광수;이해덕
    • 대한물리치료과학회지
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    • 제4권4호
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    • pp.539-548
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    • 1997
  • The purpose of this study was to determine the effects of FES on the clinical test patients who had disturbance gait due to cereberal vascular accident. The subjects for study were 16 hemiplegic patients (9 Male and 7 Female) who can gait with or without device. Their average age was 55 and they received average of 20.19 month of treatment collected data analysis was completed by using one-way analysis variable(ANOVA), Pearson ($-1{\leq}r{\geq}1$). The results were as follows : 1) There was difference in four variable (stride length,gait speed,gait cadence) between at the biginning and at the end of the treatment of FES (p<0.01). 2) There was relationship in capacity of activity between MAS and stride length (r = 0.751), gait speed (r = 0.689) but no relationship gait cadence (r = 0.236). 3) Age revealed relationship of stride length (r = -0.727), gait speed (r = -0.725), gait cadenc (r = -0.362). 4) There was no relationship in months post-CVA with MAS (r = 0.171), stride length (r = -0.110), gait speed (r = -0.096), gait cacedce (r = -0.154).

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유기용제 취급근로자가 호소하는 신체증상과 그 인식 및 태도에 관한 연구 (The Physical, Behavioral Effects and the Recognition about the Hazard Factors in the Organic Solvents Related Industry)

  • 조정민;이숙희
    • 한국보건간호학회지
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    • 제8권2호
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    • pp.57-64
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    • 1994
  • The purpose of this study is to investigate the present state of worker's physical. behavioral effects and recognition about the hazard factors in their workplace. The subject consisted of 208 workers in the organic solvents related industry. The workers were surveyed by means of a Questionnaire during the period of March 24 to May 26. 1994. The data were analyzed by descriptive statistics. t-test. AVOVA using the SAS program. The result of the study are follows: 1. The more than half of workers in the organic solvents related industry have experienced 'eye disturbance', 'headache', 'sputum formation' and 'dizziness'. 2. $83.4\%$ of workers have recognized the name of organic solvents in using of their workplace. $62.4\%$ of workers have recognized the harmfulness of organic solvents. $41.7\%$ of workers have not recognized the difference of harmfulness of various organic solvents. 3. $27.8\%$ of workers have called on clinic when have experienced physical symptoms. About $90\%$ of workers have called on hospitals and drugstores when have experienced physical symptoms.

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