• Title/Summary/Keyword: impulses

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A Study on Vibration Reduction of an Industrial Chop saw in operation (산업용 고속절단기의 기동 시 충격완화에 대한 연구)

  • Kim, Doo-Hwan;Im, Hyung-Bin;Chung, Jin-Tai
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.955-960
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    • 2008
  • In this paper, an impulse of an industrial chop Saw is identified by experimental method and the impulse is reduced by structural modification. For the impulse identification, vibration signals are measured by an accelerometer when the chop saw is operating. From some experiments, it is found that the impulse occurs when there is slip between spindle and the wheelwasher and contact area is small between the wheelwasher and cutting discs. The design of the wheelwasher for optimization is performed by the FEM and experiments and the prototype is manufactured. It is verified that considerable amount of impulses are reduced by the structural modification.

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Aesthetic Characteristics of Women's Classic Tailored Suits in Modern Fashion (현대 패션에 나타난 클래식 테일러드 수트의 미적 특성)

  • 함연자
    • Journal of the Korean Society of Costume
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    • v.53 no.6
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    • pp.101-115
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    • 2003
  • The purpose of this study is to define women's classic tailored suits surviving, despite current millennial impulses tend toward disintegration in style. Through documentary study, the reason which women had chosen the mannish tailored suits instead of sumptuous dresses in the 20th century beginnings is considered carefully. Also, examining the process of transition of women's classic suits makes it possible to infer the aesthetic characteristics of them. According to study, women had began to wear tailored suits acquiring physical comfort and the equality of the sexes. In the early stage, women imitated men's tailored suits in order to show seriousness, intelligent, capability for social success. However, in accordance with the advance of women's social position women modified it to suits themselves to present intrinsic feminity as well as masculine values. By staying the basic form, classic tailored suits have undergone constant internal changes in relation to sexuality. The aesthetic properties of women's classic tailored suits can be inferred as moderation, dualism, and versatility. In conclusion, the credibility with own authority and the evolutionary character inhering in the classic tailored suits could explain the continuity of them.

Design of a Mobile Phone Structure for the Improved Stability (이동 전화기의 기구구조 안정화설계)

  • Ro, Seung-Hoon;Shon, Jae-Yul
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.4 no.3
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    • pp.20-31
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    • 2005
  • The contents of mobile phones are rapidly appended and the structures are being changed substantially. Most of the problems with mobile phones are related with the vibrations and the displacements of PCB boards. In this study, the vibration magnitudes of the boards by impulses on the case are analyzed with the variations of the selected design parameters. The result shows that the extensive suppression of the vibrations are feasible by the proper selection of the design parameters. Also the suggested relationships between the parameter selections and the magnitudes of vibrations can be applied to establish a database for improved stability of the mobile phone structure which is a critical concern considering the short life span of the mobile phone models.

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Urinary incontinence - Anatomy and physiology of bladder and bowel - (요실금 - 방광과 장의 해부학적, 생리학적 연관성 -)

  • Lee, Jung Won
    • Clinical and Experimental Pediatrics
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    • v.51 no.11
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    • pp.1136-1139
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    • 2008
  • The genitourinary tract and gastrointestinal system are interdependent but share the same embryological origin, pelvic region, and sacral innervation. Although children with voiding disturbances often present with bowel dysfunction, this coexistence was considered coincidental until recently. However, it is now accepted that dysfunction in emptying of both systems is interrelated. Afferent impulses carrying sensory information are transmitted through the spinal cord and brainstem toward several cortical and subcortical areas, resulting in conscious control of the bladder and bowel. Alteration in these afferent pathways can result in dysfunction, including urinary and fecal incontinence. Distal gastrointestinal tract problems such as constipation might induce an inhibitory rectovesical reflex that interferes with normal voiding. Therefore, lower urinary tract function seems to be closely associated with distal gastrointestinal tract function.

Control Strategy to Reduce Tracking Error by Impulsive Torques at the Joint

  • Yang Chulho
    • International Journal of Precision Engineering and Manufacturing
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    • v.6 no.2
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    • pp.61-71
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    • 2005
  • The study reported deals with investigating the feasibility of control strategy for a serial rigid link manipulator that applies impulsive torques at the joints. The strategy is illustrated for a planar three rigid link manipulator. An impulse-based concept which uses successive torque impulses on rigid link as the controller for motion correction was introduced. This control strategy was tested over the entire trajectory to demonstrate that the tracking error could be reduced effectively. The best condition for minimizing the tracking error with the least impulse input at each joint is investigated by considering one design and one operating parameter. The first was the damping in the system, and the second was the sampling time during operation. The results show that this approach can provide useful guidance for the design and control of robot manipulators that require minimum impulse feedback for accurate tracking.

Control of the Residual Vibration of Crane Using Equivalent Input Shaper (등가입력성형기를 이용한 크레인의 잔류진동 제어)

  • Park, Un-Hwan;Lee, Jae-Won;Noh, Sang-Hyun;Yoon, Ji-Sup;Park, Byung-Suk
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.1
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    • pp.135-142
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    • 2002
  • Input shaping is a method for reducing residual vibration in computer controlled machines. Vibration is eliminated by convolving a sequence of impulses, an input shaper, with a desired system command to produce a shaped input. This paper shows the shape of sensitivity curve of input shaper as impulse interval T and analysis of robustness for input shaper on the z-plane. And a method is presented for designing equivalent input shaper considering sampling time $T_s$. And then we applied equivalent input shaper to crane system.

Analysis of Unmet Medical Needs according to Mental Health (정신건강유형에 따른 미충족 의료 현황 분석)

  • Choi, Ryoung;Hwang, Byung-Deog
    • The Korean Journal of Health Service Management
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    • v.10 no.1
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    • pp.117-129
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    • 2016
  • Objectives : This study investigated the prevalence of unmet health care needs among Korean adults and related factors. Methods : The study participants were adults over the age of 20 mental health experience from the Korea Health Panel in 2012(n=4,730). Statistical analysis methods used in this study were the ${\chi}^2$-test, Logistic Regression Analysis and other basic statistics such frequency-and percentage using SPSS version 22.0. Results : (1)Significant variables of stress: Factors were age, economic activity, subjective health status, and activity limitation. (2)Significant variables of depression: Factors were age, income class(low) and activity limitation. (3)Significant variables of suicidal impulse: Factors were age, chronic diseases, income class, and activity limitation. Conclusions : Stress, depression, and suicidal impulse can be unmet medical factors; therefore improvement measures and mental health counseling programs in response to suicide impulses, should be developed. Thus there is a need for a health sciences approach.

Effects of Artificial Vibrations on Strength and Physical Properties of Curing Concrete (인공진동의 크기가 양생콘크리트의 강도와 물성에 미치는 영향)

  • 임한욱;정동호;이상은
    • Tunnel and Underground Space
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    • v.4 no.1
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    • pp.31-37
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    • 1994
  • The effects of blasting and ground vibratons on curing concrete have not been well studied. As a results unrealistic and costly ground vibration constraints have been placed on blasting and piling when it occurs in the vicinity of curing concrete. To study the effects of ground vibrations, a shaking table was made to produce peak particle velocities in the nearly same frequency range as found in construction blasting. Concrete blocks of 33.3X27.7X16.2cm were molded and placed on the shaking table. Different sets of concrete blocks were subjected to peak vibrations of 0.25, 0.5, 1.0, 5.0 and 10cm/sec. The impulses were applied at two hour intervals for thirty seconds. Along with unvibrated concrete blocks, the vibrated concrete samples with 60.3mm in diameters were measured for elastic moduli, sonic velocity, tensile and uniaxial compressive strength. Test results showed that the vibrations in curing concrete generally have effects on the uniaxial compressive strength or physical properties of the concrete.

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Implantation of dual chamber pacemaker: report of 2 cases (생리적 심박동조절이 가능한 Dual Chamber Pacemaker이식 치험 2)

  • 김은기
    • Journal of Chest Surgery
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    • v.16 no.4
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    • pp.547-554
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    • 1983
  • Implantation of Dual Chamber Pacemakers Which sense in the Atrium and the Ventricle, and sequentially or synchronously trigger impulses in the both chambers, has led us to the near realization of the ideal "Physiologic Pacing". We have experienced two cases of implantation of Dual chamber pacemaker in September and October, 1983. One patient was a 21-year-old male who had postoperative complete heart block since he was taken Total correction of TOF in May, 1983 . We implanted transvenously a dual chamber pacemaker, VDD type, through the left subclavian vein. In the other patient who came to the emergency room for partial obstruction of small bowels with severe abdominal pain, nausea and vomiting, in whom heart block was found, we implanted a DDD type pacemaker through the left subclavian puncture. The pacemakers have been functioning well postoperatively for more than two months, and the conditions of patient were uneventful.

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Global Attractivity and Oscillations in a Nonlinear Impulsive Parabolic Equation with Delay

  • Wang, Xiao;Li, Zhixiang
    • Kyungpook Mathematical Journal
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    • v.48 no.4
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    • pp.593-611
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    • 2008
  • Global attractivity and oscillatory behavior of the following nonlinear impulsive parabolic differential equation which is a general form of many population models $$\array{\{{{\frac {{\partial}u(t,x)}{{\partial}t}=\Delta}u(t,x)-{\delta}u(t,x)+f(u(t-\tau,x)),\;t{\neq}t_k,\\u(t^+_k,x)-u(t_k,x)=g_k(u(t_k,x)),\;k{\in}I_\infty,}\;\;\;\;\;\;\;\;(*)$$ are considered. Some new sufficient conditions for global attractivity and oscillation of the solutions of (*) with Neumann boundary condition are established. These results no only are true but also improve and complement existing results for (*) without diffusion or impulses. Moreover, when these results are applied to the Nicholson's blowflies model and the model of Hematopoiesis, some new results are obtained.