• Title/Summary/Keyword: focus control

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Dynamic Characteristics Analysis of 3D Conveyor System Linear Induction Motor for Control Algorithm Developments (제어알고리즘 개선을 위한 3차원 반송 시스템 선형유도전동기의 동특성 해석)

  • Jeon, Su-Jin;Lee, Min-Myeong;Lee, Jung-Ho
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.683-684
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    • 2006
  • It is necessary to modify the state-of-the-art of speed control theory because of the phase asymmetry in the Linear Induction Motor (LIM)and for the constant speed control of mover using single vector control inverter system, it is important that primary stack is located in appropriated intervals in the 3D conveyer system using LIM. The dynamic characteristic analysis method of the vector controlled LIM using coupled FEM and control algorithm taking into account the movement is proposed. The focus of this paper is the analysis relative to selecting primary stack intervals in order to constant speed control in the 3D conveyer system using LIM.

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Development of damage control training scenarios of naval ships based on simplified vulnerability analysis results

  • Park, Dong-Ki;Shin, Yun-Ho;Chung, Jung-Hoon;Jung, Eui S.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.8 no.4
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    • pp.386-397
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    • 2016
  • Given the growing interest in damage control training for the naval ships and their organizations, expectations for a new concept of training program have also increased. The existing training programs and its concept focus on training crew to be more proficient and skilled so that they can respond better to damage situations, i.e., fires and flooding. This paper suggests a development procedure of damage control training scenarios using the survivability analysis results as a new concept of damage control training programs employing advanced systems such as damage control console, automation system, and kill cards. This approach could help the decision maker not only enhance his or her capability but also improve the reacting capability of crew members for complex situations induced by a weapon hit.

Improvement in rise time and robustness of AC servomotor (AC servo motor 제어시 rise time 과 강인성 개선)

  • 정광조;임선종
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10a
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    • pp.446-450
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    • 1991
  • PID controller is popular but have defect inversing following reference input and noise elimination. Therefor, this paper focus on reducing rise time and robustness against noise. The result that is simulated with feedforward method and sliding mode show that rise time decrease and robustness increase.

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The 3D Depth Extraction Method by Edge Information Analysis in Extended Depth of Focus Algorithm (확장된 피사계 심도 알고리즘에서 엣지 정보 분석에 의한 3차원 깊이 정보 추출 방법)

  • Kang, Sunwoo;Kim, Joon Seek;Joo, Hyonam
    • Journal of Institute of Control, Robotics and Systems
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    • v.22 no.2
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    • pp.139-146
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    • 2016
  • Recently, popularity of 3D technology has been growing significantly and it has many application parts in the various fields of industry. In order to overcome the limitations of 2D machine vision technologies based on 2D image, we need the 3D measurement technologies. There are many 3D measurement methods as such scanning probe microscope, phase shifting interferometry, confocal scanning microscope, white-light scanning interferometry, and so on. In this paper, we have used the extended depth of focus (EDF) algorithm among 3D measurement methods. The EDF algorithm is the method which extracts the 3D information from 2D images acquired by short range depth camera. In this paper, we propose the EDF algorithm using the edge informations of images and the average values of all pixel on z-axis to improve the performance of conventional method. To verify the performance of the proposed method, we use the various synthetic images made by point spread function(PSF) algorithm. We can correctly make a comparison between the performance of proposed method and conventional one because the depth information of these synthetic images was known. Through the experimental results, the PSNR of the proposed algorithm was improved about 1 ~ 30 dB than conventional method.

Focal Length Control of Line-focus Ultrasonic Transducer Using Bimorph-type Bending Actuator (바이몰프형 밴딩 액츄에이터를 이용한 선집속형 초음파 트랜스듀서의 초점 거리 제어)

  • 채민구;하강열;김무준
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.3
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    • pp.202-207
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    • 2003
  • For medical ultrasonic transducer, phase-weighting method has been used for controlling focal length with electric circuit at each vibrating element. However, the electric circuit is complex as the number of vibrating elements is increased. In this paper, we fabricated line-focus transducer with a bimorph-type piezoelectric actuator. The polyvinylidene fluoride (PVDF) piezoelectric type polymer film is used for transmitting and receiving of ultrasonic signal. Using this transducer, focal length of the transducer can be controlled mechanically by changing voltage of the actuator. It is confirmed that focal length of the transducer can be controlled in range of 1095 to radius of curvature.

Burnout Experience of HIV Counseling Nurses (HIV감염인 상담간호사의 소진경험)

  • Seo, Myoung Hee;Jeong, Seok Hee;Lee, Myung Ha;Kim, Hyun Kyung
    • Journal of Korean Academy of Nursing Administration
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    • v.19 no.4
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    • pp.544-554
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    • 2013
  • Purpose: This study was designed to describe the burnout experiences of nurses counseling people living with HIV/AIDS (PLWHA) in hospital-based counseling services in Korea. Methods: A qualitative research technique with focus group interviews was used and the data were collected in 2012. Participants were 13 counseling nurses from 16 medical hospitals in South Korea who had worked full-time for more than six months as a counseling nurse for PLWHA. The 13 nurses made up 68.4% of all 19 official HIV counseling nurses in South Korea. Data were collected using focus group interviews and analyzed with the content analysis methodology of Downe-Wamboldt. Results: Burnout experience of counseling nurses for PLWHA was analyzed for two domains-causes of, and effects of burnout. Each domain was classified into three categories; personal, job-related, and relationships. Further 17 sub-categories and 47 concepts were discovered. Conclusion: In this study various causes and effects of burnout experienced by nurses counseling PLWHA were identified. These findings can be used in developing effective strategies for nurses, administrators, and health policy makers to solve the burnout of counseling nurses. Further research is required to develop detailed and practical job description for nurses counseling PLWHA.

An Omnidirectional Vision-Based Moving Obstacle Detection in Mobile Robot

  • Kim, Jong-Cheol;Suga, Yasuo
    • International Journal of Control, Automation, and Systems
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    • v.5 no.6
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    • pp.663-673
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    • 2007
  • This paper presents a new moving obstacle detection method using an optical flow in mobile robot with an omnidirectional camera. Because an omnidirectional camera consists of a nonlinear mirror and CCD camera, the optical flow pattern in omnidirectional image is different from the pattern in perspective camera. The geometry characteristic of an omnidirectional camera has influence on the optical flow in omnidirectional image. When a mobile robot with an omnidirectional camera moves, the optical flow is not only theoretically calculated in omnidirectional image, but also investigated in omnidirectional and panoramic images. In this paper, the panoramic image is generalized from an omnidirectional image using the geometry of an omnidirectional camera. In particular, Focus of expansion (FOE) and focus of contraction (FOC) vectors are defined from the estimated optical flow in omnidirectional and panoramic images. FOE and FOC vectors are used as reference vectors for the relative evaluation of optical flow. The moving obstacle is turned out through the relative evaluation of optical flows. The proposed algorithm is tested in four motions of a mobile robot including straight forward, left turn, right turn and rotation. The effectiveness of the proposed method is shown by the experimental results.

Development of a Dan J eon Breathing Model for Health Promotion in Middle-aged Women (중년여성의 건강증진을 위한 단전호흡 모형 개발)

  • Kim Kyung-Won
    • Journal of Korean Academy of Nursing
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    • v.35 no.3
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    • pp.565-574
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    • 2005
  • Purpose: The purpose of this study was to develop a Dan Jeon Breathing Model and to identify effects of the developed Dan Jeon Breathing Model for maintenance and promotion of health and improvement of health problems in middle-aged women. Method: This study was constructed with two procedures. The first procedure was to develop appropriate movements for middle-aged women, performing a focus group discussion and developing a Dan Jeon Breathing Model in qualitative research. The collected data from focus group discussions was categorized for fitting movements. The second procedure was to verify and conclude a Hypothetic Dan Jeon Breathing Model through a quasi-experimental nonequivalent control group pre-post test design. Result: The developed Dan Jeon Breathing Model was composed of 28 preparation movements to accept Ki comfortably, 10 breathing movements to accumulate Ki for activation of metabolic function in organs and 14 finishing movements to transmit activated Ki to organs. It took 40 minutes to do them. In the Second procedure, the score of physical health (t=4.205, p=.000), psycho-social health(t=3.292, p=.002) and physical strength of the experimental group(t=5.905, p=.000) was higher than that of the control group. Conclusion: The Dan Jeon Breathing Model developed in this study is the correct health promotion model for middle-aged women, their demand, developmental traits and health problems.

Comparison of Sitting Balance and Coordination in Children with Spastic Cerebral Palsy Using the Korean Version of Trunk Impairment Scale (K-TIS)

  • Jung, Hye-Rim;Choi, Young-Eun
    • Journal of the Korean Society of Physical Medicine
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    • v.14 no.4
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    • pp.37-44
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    • 2019
  • PURPOSE: The purpose of this study was to compare sitting balance and coordination spastic cerebral palsy in children using the Korean version of Trunk Impairment Scale (K-TIS) as well as to provide basic data about effective postural control treatment for clinicians handling these two types. METHODS: The K-TIS was measured in 29 children diagnosed with diplegic and quadriplegic cerebral palsy (18 with diplegia and 11 with quadriplegia). The average and standard scores of the children's K-TIS subscales and items of the two groups were measured. The two groups' subscales and items were analyzed by using the Mann-Whitney U test. RESULTS: Static sitting balance, dynamic sitting balance, coordination, and total score for children with diplegia were statistically high (p<.05). For all items under static sitting balance, the score for children with diplegia was higher. The first differences in the repeated items of dynamic sitting balance and coordination area that rotates between the upper and lower body were presented. CONCLUSION: The difference in balance and coordination in sitting positions is exhibited in children with diplegia and quadriplegia. For children with spastic quadriplegia, treatments should focus on static sitting balance and coordination, together with a focus on dynamic sitting balance and coordination.

Micro Channel Fabrication Technology Using UV Laser Micromachining (UV 레이저 마이크로머시닝을 이용한 마이크로 채널 제작기술)

  • 양성빈;장원석;김재구;신보성;전병희
    • Transactions of Materials Processing
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    • v.13 no.3
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    • pp.216-224
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    • 2004
  • In this study, we have developed a new UV$({\lambda}=355nm)$ laser micromachining technology by direct ablation method without masks. This technology allows that 3D micro parts can be fabricated rapidly and efficiently with a low price. And it has a benefit of reducing fabricating process simply. Due to micro parts' fabrication, such technologies need the control of XYZ stages with high precision, the design of optical devices to maintain micron spot sizes of laser beam and the control technology of laser focus. The developed laser manufacturing process for laser micromachining is that, after extracting coordinates of shape data from CAD model data, a beam path considering manufacturing features of laser beam is created by using genetic algorithm. This generated manufacturing process is sent to stage controller. In order to improve the surface quality of micro parts, we have carried out experiments on iteration manufacturing and beam step-over by using a minimum focus size. Moreover, we have fabricated a micro-channel through the developed laser micromachining technology and verified it through the results.