• Title/Summary/Keyword: mechanism functions

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Design of a Swing-arm Actuator using the Compliant Mechanism - Multi-objective Optimal Design Considering the Stiffness Effect (컴플라이언트 메커니즘을 이용한 스윙 암 액추에이터의 설계 - 강성 효과를 고려한 다중목적 최적화 설계 -)

  • Lee Choong-yong;Min Seungjae;Yoo Jeonghoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.2 s.245
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    • pp.128-134
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    • 2006
  • Topology optimization is an effective scheme to obtain the initial design concept: however, it is hard to apply in case of non-linear or multi-objective problems. In this study, a modified topology optimization method is proposed to generate a structure of a swing arm type actuator satisfying maximum compliance as well. as maximum stiffness using the multi-objective optimization. approach. The multi-objective function is defined to maximize the compliance in the direction of focusing of the actuator and the second eigen-frequency of the structure. The design of experiments are performed and the response surface functions are formulated to construct the multi-objective function. The weighting factors between conflicting functions are determined by the back-error propagation neural network and the solution of multi-objective function is acquired using the genetic algorithm.

A Case of Mucus Plug Impaction resulted in Bronchial Obstruction (광범위 기관지 폐쇄를 유발한 점액전 1례)

  • 고중화;전영명;김휘준
    • Korean Journal of Bronchoesophagology
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    • v.3 no.2
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    • pp.313-317
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    • 1997
  • Airway mucus provides the protective functions such as lubrication, barrier, disposal of trapped materials, and humidification. In the normal state, the mucus do not interfere with Bas transport and the other vital functions of lung. In diseases such as asthma, bronchitis, and cystic fibrosis, the mucus hypersecretion was physiologically developed in the response of multiple neurohumoral mechanism system. And regardless of the mechanism, many clinical sequelae result from mucus hypersecretion: atelectasis, infection, increased airway resistance, increased work of breathing, increased cough with its resultant complication. And the condensation of mucus tv mucus hypersecretion can make the mucus plug by which bronchial obstruction is developed. We have experienced a 7 Pear-old male patient with recurrent pneumonic symtom, which the bronchial obstruction was developed by the impacted mucus plug on the bronchoscopic finding. We report this case with the review of literature.

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Fat Cell Formation and Obesity-Related Diseases

  • Kawada, Teruo
    • Preventive Nutrition and Food Science
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    • v.8 no.1
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    • pp.105-112
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    • 2003
  • Animals possess a highly sophisticated mechanism of storing energy in adipose tissue inside their bodies. However, in humans it has been clarified that adipocyte (fat cell), which composes the body fat (adipose) tissues, development and the extent of subsequent fat accumulation are closely associated with the occurrence and advancement of various common diseases (e.g., type-2 diabetes, coronary artery disease, and hypertension) resulting from obesity. Recent exciting progress in clinical and biochemical studies of adipocytes has rapidly clarified the functions of adipocytes and adipose tissue. Interesting findings are the function of white adipocytes as "secreting cells" and the molecular mechanism undelying adipocyte differentiation at the transcriptional level in relation to nuclear receptors. Consequently, the adipose tissue is being targeted for the prevention or treatment of many common diseases. In this review, I will focus on recent information on characteristics of adipocytes and the relationship between obesity and common obesity-related diseases. diseases.

A VPC/VCC managment scheme of ATM network using SNMP (SNMP를 이용한 ATM망의 VPC/VCC 관리 기법)

  • 송운섭;이길흥;최용훈;이준호;강태원;김석규;이재용;이상배
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.3
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    • pp.580-592
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    • 1997
  • Since an ATM network consists of a number of VPC/VCC requiring various QoS requirements, the end-to-end QoS for each VPC/VCC should be guaranteed. Although many research works on the traffic control are under study to guarantee the QoS, there have been research efforts to reflect the results of network management functions into the traffic control mechanism. To effectively make use of the performance management functions into the VPC/VCC management, threre is a need for the network manager to rapidly retrieve the relevant information. In this research, the mechanism to effectively retrieve the management information using SNMP is suggested. First of all, we construct the MIBs in the agent for the corresponding VPC/VCC. Also, we suggest the way to retrieve MIB with minimum cost. Mathematical analysis shows that the proposed technique has better performance than that using the existing SNMP.

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Development of Power Controller for Control Rod Drive Mechanism in Reactor (원자로 제어봉 구동장치 제어시스템용 전력제어기 개발)

  • Kim, Choon-Kyung;Cheon, Jong-Min;Lee, Jong-Moo;Kwon, Soon-Man
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.575-579
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    • 2003
  • In this paper, we describe a Duplex Power Controller for Control Rod Control System(CRCS). A Duplex Power Controller has the various functions for the reliable operations of Control Rod Drive Mechanism(CRDM). Also we have implemented the diverse functions by utilizing the developed Duplex Power Controller. Due to the developed Duplex Power Controller, we are assured that the commercial operation by this system be made before long.

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Phytobiotics to improve health and production of broiler chickens: functions beyond the antioxidant activity

  • Kikusato, Motoi
    • Animal Bioscience
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    • v.34 no.3_spc
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    • pp.345-353
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    • 2021
  • Phytobiotics, also known as phytochemicals or phytogenics, have a wide variety of biological activities and have recently emerged as alternatives to synthetic antibiotic growth promoters. Numerous studies have reported the growth-promoting effects of phytobiotics in chickens, but their precise mechanism of action is yet to be elucidated. Phytobiotics are traditionally known for their antioxidant activity. However, extensive investigations have shown that these compounds also have anti-inflammatory, antimicrobial, and transcription-modulating effects. Phytobiotics are non-nutritive constituents, and their bioavailability is low. Nonetheless, their beneficial effects have been observed in several tissues or organs. The health benefits of the ingestion of phytobiotics are attributed to their antioxidant activity. However, several studies have revealed that not all these benefits could be explained by the antioxidant effects alone. In this review, I focused on the bioavailability of phytobiotics and the possible mechanisms underlying their overall effects on intestinal barrier functions, inflammatory status, gut microbiota, systemic inflammation, and metabolism, rather than the specific effects of each compound. I also discuss the possible mechanisms by which phytobiotics contribute to growth promotion in chickens.

On the Design of the Latch Mechanism for Wafer Containers in a SMIF Environment

  • Lee, Jyh-Jone;Chen, Dar-Zen;Pai, Wei-Ming;Wu, Tzong-Ming
    • Journal of Mechanical Science and Technology
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    • v.20 no.12
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    • pp.2025-2033
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    • 2006
  • This paper presents, the design of a latch mechanism for wafer containers in a standard mechanical interface environment. For an integrated circuits fabrication factory, the standard mechanical interfaced wafer container is an effective tool to prevent wafers from particle contamination during wafer storage, transporting or transferring. The latch mechanism inside the container door is used to latch and further seal the wafer container for safety and air quality. Kinematic characteristics of the mechanism are established by analyzing the required functions of the mechanisms. Based on these characteristics, a methodology for enumerating feasible latch mechanisms is developed. New mechanisms with one degree-of-freedom and up to five links are generated. An optimum design is also identified with respect to the criteria pertinent to the application. The computer-aided simulation is also built to verify the design.

Cam Profile Design for Precision Positioning (정밀위치결정을 위한 캠 형상 설계)

  • 이종호;이종길;김병희;전병희
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2003.05a
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    • pp.204-209
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    • 2003
  • Cam mechanisms are one of the most popular devices for generating intermittent motion and are widely used in many areas. Also, as being interested in research of precision field, cam mechanism is required high accuracy and continuity, In. In this paper, the cam mechanism of filament automatic assembly machine design for precision motion is proposed. The modelling of a cam mechanism, cam profile functions, and the design of the cam considering the precision positioning of the cam mechanism is studied. And, simulation of designed cam mechanism had been carried out dynamic analysis.

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A Study on the Optimal Design of a R-S-S-R Three Dimensional Mechanism (3次元 R-S-S-R 機構의 最適設計 에 관한 硏究)

  • 김호룡;김경률
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.9 no.4
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    • pp.528-538
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    • 1985
  • A R-S-S-R three dimensional mechanism is designed for crank-rocker type through the optimization technique. The nonlinear kinematic equation of the mechanism is formulated by adopting the concept of structural error and precision points. Taking this equation as an objective function, the required mechanism is optimally synthesized by the Fletcher-Davidon-Powell's method of optimization techniques. The structural errors due to the various positions of precision points are compared, and the results from the use of two penalty functions suggested respectively by Fiacco-McCormick and by Powell are also compared on their effectiveness. The mobility of the optimally designed mechanism is checked for the possibility of its motion, and when a mechanism is optimally designed, it is strongly suggested that the mobility must be checked on the designed mechanism.

A Remote Firmware Update Mechanism for a TDMA-based Bidirectional Linear Wireless Sensor Network (양방향 통신을 지원하는 시분할 기반 선형 무선 센서 네트워크를 위한 원격 펌웨어 업데이트 방법)

  • Moon, Jung-Ho;Kim, Dae-Il;Park, Lae-Jeong;Lee, Hyung-Bong;Chung, Tae-Yoon
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.8
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    • pp.867-875
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    • 2009
  • A wireless sensor network inherently comprises a plurality of sensor nodes widely deployed for sensing environmental information. To add new functions or to correct some faulty functions of an existing wireless sensor network, the firmware for each sensor node needs to be updated. Firmware update would be quite troublesome if it requires the gathering, reprogramming, and redeploy of all of already deployed sensor nodes. Over-the-air programming (OTA) facilitates the firmware update process, thereby allowing convenient maintenance of an already-deployed sensor network. This paper proposes and implements a remote firmware update mechanism for a TDMA-based wireless sensor network, in which the firmware for sensor nodes constituting the TDMA-based sensor network can be easily updated and the update process can be conveniently monitored from a remote site. We verify the validity of the proposed firmware update method via experiments and introduce three wireless sensor networks installed in outdoor sites in which the proposed firmware update mechanism has been exploited.