• Title/Summary/Keyword: SUSPENSION

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A Study on Characteristic of Filter Processing Using Kozeny-Carman Model and Measuring of PCS (PCS측정 기술과 Kozeny-Carman 모델을 이용한 여과공정 특성연구)

  • Ha, Sang An;Kim, Seung Ho;Yun, Tae Gyeong
    • Journal of Environmental Science International
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    • v.13 no.9
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    • pp.799-806
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    • 2004
  • The filtration tests were made in cell with a low concentrated suspension. The suspension with a concentration of $C_{M}$=1.14~2.67$\cdot$$10^{-3}$ g/g consists of paper paint and water. The particles in the suspension have a particle size x<1${\mu}m$. The used depth filters consists of glass fibres, which are coated by polymer. The filtration in depth filters accorded in different mechanism, which were explained by physical models. The model which would be allows to make a promise of the filtration reaction. This filter media allows to get a high filtration time and a good separation rate. The Particle distribution is measured by a photon correlation spectroscopy(PCS). PCS measures particle sizes 0.03 ${\mu}m$${\mu}m$ in the suspension. The filtered suspension has a very low concentration Co{\le}5{\times}10_{-4}$ g/g of solid in sample. The PCS also informs us about the number of the particles in the suspension. The makes it possible to calculate the concentration of the in sample.

Design of A Controller for Vehicle Active Suspensions Considering Driving Conditions (주행 상황을 고려한 차량 능동 현가장치 제어기 설계)

  • Cheon Jong-Min;Lee Jong-Moo;Kwon Soonman;Choi Young-Kiu
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.54 no.12
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    • pp.698-704
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    • 2005
  • Passive suspensions with fixed design constants are very restrictive in the inherent suspension problem, the trade-off between the ride quality and the suspension travel. Active suspensions are used to solve some drawbacks of passive suspensions. In this paper, we propose a controller design for vehicle active suspensions considering variable driving conditions. Our controller estimates the current driving conditions by detecting the road frequencies gotten from Fourier Transform and decides which factor must be emphasized between the ride quality and the suspension travel. In one case of focusing on the ride quality, we use the skyhook control law and in the other case of focusing on the suspension travel, the double skyhook control law is used. The control law modified by various road situations outputs the reference force value the electro-hydraulic actuator in active suspension system must generate. To track the reference force, we adopt the sliding control law which is very useful in controlling the nonlinear system like the electro-hydraulic actuator.

New Milliactuator Embedded Suspension (밀리엑츄에이터가 내재된 신규 서스펜션)

  • Yoon, Joon-Hyun;Hong, Eo-Jin;Yang, Hyun-Seok;Park, Young-Pil
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.477-482
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    • 2001
  • To realize higher track density of HDD, the servo bandwidth should be higher, however, is limited by the mechanical resonances of the arm, coil of the VCM and ball bearing pivot. The dual-stage actuator systems have been suggested as a possible solution. For the dual-stage actuator systems based on the suspension, the suspension resonance frequencies in the radial access direction are important factors to increase a servo bandwidth, however the improvement of these frequencies may affect the shock resistance performance and spring constant. The slider's flying stability can be deteriorated by the change of a vertical stiffness. In this work, we have investigated a suspension design scheme possessing a milliactuator for dual-stage actuator systems and also achieved higher mechanical characteristics. Design parameters are deduced by finite element analysis with sensitivity function. It is confirmed that the proposed suspension with the milliactuator has the capability of fine tracking motion, due to its hinge structure on the spring region, and achieves higher mechanical resonance frequencies in the radial access direction with a high-shock resistance and a low-spring constant.

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A Study of Whether Extinctive Prescription and Joint Payment Apply to the Right of Imposing Fine on the Law of National Health Insurance or Not ("국민건강보험법" 상 과징금부과처분 권한에 대한 소멸시효 적용여부 및 과징금 연대 납부 의무 유무)

  • Park, Tae-Shin
    • The Korean Society of Law and Medicine
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    • v.12 no.2
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    • pp.189-217
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    • 2011
  • According to the current law of national health insurance, the Minister of Health and Welfare can impose a suspension of business or license, and a fine with medical institutions who violate the law. In case that medical institutions raise an action for ity with each penalty, they ask for replacing the suspension of business with a fine during the pendency of the action. But there is a long gap of time between an offense and administrative measures. One violation cause several types of administrative measures (suspension of business or fine, suspension of license etc.) and different government departments impose these penalties. It takes a lot of time to organize their opinions and they are liable to impose penalties after considerable space of time because of overwhelming tasks. Then the medical institutions can sustain a loss by getting unexpected administrative measures after their offense against the law. Thus, this article review whether extinctive prescription apply to the right of imposing fine on the law of national health insurance or not. Meanwhile, we have no regulations imposing a same fine to co-representatives of medical institution who infringe the law of national health insurance. On this point, this study review whether they have equal duty on that or not.

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Seismic performance and its favorable structural system of three-tower suspension bridge

  • Zhang, Xin-Jun;Fu, Guo-Ning
    • Structural Engineering and Mechanics
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    • v.50 no.2
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    • pp.215-229
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    • 2014
  • Due to the lack of effective longitudinal constraint for center tower, structural stiffness of three-tower suspension bridge becomes less than that of two-tower suspension bridge, and therefore it becomes more susceptible to the seismic action. By taking a three-tower suspension bridge-the Taizhou Highway Bridge over the Yangtze River with two main spans of 1080 m as example, structural dynamic characteristics and seismic performance of the bridge is investigated, and the effects of cable's sag to span ratio, structural stiffness of the center tower, and longitudinal constraint of the girder on seismic response of the bridge are also investigated, and the favorable structural system is discussed with respect to seismic performance. The results show that structural response under lateral seismic action is more remarkable, especially for the side towers, and therefore more attentions should be paid to the lateral seismic performance and also the side towers. Large cable's sag, flexible center tower and the longitudinal elastic cable between the center tower and the girder are favorable to improve structural seismic performance of long-span three-tower suspension bridges.

Prevention of Lower Eyelid Complications Caused by a Subciliary Approach: Temporary Lower Eyelid Suspension (속눈썹밑 접근법에 의한 아래눈꺼풀 합병증의 예방: 일시적 아래눈꺼풀 걸기술)

  • Burm, Jin Sik;Kim, Boo Yeong;Kim, Yang Woo
    • Archives of Plastic Surgery
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    • v.33 no.4
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    • pp.465-468
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    • 2006
  • Purpose: Subciliary approaches to orbitozygomatic fractures have high incidence of complications such as scleral show and ectropion. Abnormal rearrangement of eyelid flaps may be a very important factor to induce abnormal cicatrical and consequent contracture. To prevent this problem, we used temporary lower eyelid suspension. Methods: A total of two hundred five patients were investigated for lower eyelid complication of orbitozygomatic fractures that underwent reconstruction with subciliary approach. The lower eyelid margin was pulled up toward the forehead using lower eyelid suspension suture to stretch the lower lid flaps. The lid suspension was maintained for one day after surgery. Results: The complications of the lower eyelid were in 15 cases(7.3%); seven cases(3.4%) of visible depressed scar, three cases(1.4%) of scleral show, two cases(1%) of ectropion, two cases(1%) of conjunctival swelling and one case(0.5%) of hematoma. Conclusions: The lower eyelid suspension seems to allow adhering lid flap in proper anatomical position and in the status of the maximal stretch and consequently preventing the severe complications such as scleral show and ectropion caused by scar contraction after subciliary approach.

Self-Tuning Gain-Scheduled Skyhook Control for Semi-Active Suspension Systems: Implementation and Experiment (반능동 현가시스템용 자기동조 게인조절형 스카이훅 제어기의 구현 및 실험)

  • Hong, Kyung-Tae;Huh, Chang-Do;Hong, Keum-Shik
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.3
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    • pp.199-207
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    • 2002
  • In this paper, a self-tuning gain-scheduled skyhook control for semi-active suspension systems is investigated. The dynamic characteristics of a continuously variable damper including electro-hydraulic pressure control valves is analyzed. A 2-d.o.f. time-varying quarter-car model that permits variations in sprung mass and suspension spring coefficient is considered. The self-tuning skyhook control algorithm proposed in this paper requires only the measurement of body acceleration. The absolute velocity of the sprung mass and the relative velocity of the suspension deflection are estimated by using integral filters. The skyhook gains are gain-scheduled in such a way that the body acceleration and the dynamic tire force are optimized. An ECU prototype is discussed. Experimental results using a 1/4-ear simulator are discussed. Also, a suspension ECU prototype targeting real implementation is provided.

Design optimization of intelligent service robot suspension system using dynamic model (동역학 모델을 활용한 서비스용 지능형 로봇의 현가시스템 설계 최적화)

  • Choi, Seong-Hoon;Park, Tae-Won;Lee, Soo-Ho;Jung, Sung-Pil
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.565-570
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    • 2008
  • Recently, the intelligent service robot is applied for the purpose of guiding the building or providing information to the visitors of the public institution. The intelligent robot which is on development has a sensor to recognize its location at the bottom of it. Four wheels which are arranged in the form of a lozenge support the weight of the components and structures of the robot. The operating environment of this robot is restricted at the uneven place because the driving part and internal structure is designed in one united body. The impact from the ground is transferred to the internal equipments and structures of the robot. This continuous impact can cause the unusual state of the precise components and weaken the connection between each structural part. In this paper, a suspension system which can be applied to the intelligent robot is designed. The dynamic model of the robot is created, and the driving characteristics of the actual robot and the robot with suspension are compared. The road condition which the robot can operate is expanded by the application of the suspension system. Additionally, the suspension system is optimized to reduce the impact to the robot components.

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Production and Secretion of Human Interleukin-18 in Transgenic Tobacco Cell Suspension Culture

  • Sharma, Niti;Kim, Tae-Geum;Yang, Moon-Sik
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.11 no.2
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    • pp.154-159
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    • 2006
  • Interleukin-18 (IL-18), otherwise known as interferon-gamma-inducing factor (IGIF), is one of several well characterized and important cytokines that contribute to host defenses. The complementary DNA (cDNA) of mature human interleukin-18 gene (hIL-18) was fused with the signal peptide of the rice amylase 1A gene (Ramy1A) and introduced into the plant expression vector under the control of a duplicated CaMV 35S promoter. The recombinant plasmid was transformed into tobacco (Nicotiana tabacum L. cv Havana) using the Agrobacterium-mediated transformation method. The integration of the hlL-18 gene into the genome of transgenic tobacco plants was confirmed by polymerase chain reaction (PCR) amplification and its expression was observed in the suspension cells that were derived from the transgenic plant callus by using Northern blot analysis. The hlL-18 protein was detected in the extracts of the transgenic callus and in the medium of the transgenic tobacco suspension culture by using immunoblot analysis. Based upon enzyme-linked immunosorbant assay (ELISA) results, the expression level of the hlL-18 protein approximated $166{\mu}g/L$ in the suspension culture medium. Bioassay results from the induction of $interferon-{\gamma}$ from a KG-1 cell line indicated that the hlL-18 secreted into the suspension culture medium was bioactive.

Dynamic Analysis of Suspension for Small Form Factor MO Drive (초소형 광자기 드라이브용 서스펜션의 동특성 해석)

  • 홍어진;오우석;박노철;양현석;박영필
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.406-411
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    • 2003
  • One of the trends on information storage device is focused on the development of micro-optical devices with OFH (Optical Flying Head). Many different types of sliders for OFH and optical component systems have been introduced in the literature. However, the important issue on the mechanical system, which consists of suspension, swing arm and VCM (Voice Coil Motor) part has not been discussed up to date. In this research, we analyses the suspension, which is used for the small form factor MO drive. The analysis is in process two ways. One is probabilistic analysis, another is dynamic shock analysis. Probabilistic analysis is a technique you can use to assess the effect of uncertain input parameters and assumptions on your analysis model. Using a probabilistic analysis you can and out how much the results of a finite elements analysis are affected by uncertainties in the model. Dynamic shock analysis is used for the mobile applications. The mechanical robustness of the suspension simulating the shock responses of a disk-suspension is proposed in this paper.

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