• 제목/요약/키워드: Body of Revolution

검색결과 105건 처리시간 0.028초

The Noise Reduction of a DC Motor Using Multi-body Dynamics

  • Jung Il-Ho;Seo Jong-Hwi;Choi Sung-Jin;Park Tae-Won;Chai Jang-Bom
    • Journal of Mechanical Science and Technology
    • /
    • 제19권spc1호
    • /
    • pp.336-342
    • /
    • 2005
  • The DC motor of a vehicle may cause noise and vibration due to high-speed revolution, which can make a driver feel uncomfortable. There have been various studies attempting to solve these problems, mostly focusing on the causes of noise and vibration and a means of preventing them. The CAE methodology is more efficient than a real test for the purpose of looking for various design parameters to reduce the noise and vibration of the DC motor. In this study, a design process for reducing brush noise is presented with the use of a computer model, which is made by using a multi-body dynamics program (DADS). The design parameters to reduce the brush noise and vibration were proposed using a computer model. They were used to reduce the noise and vibration of the DC motor and verified by the test results of the fan DC motor in the vehicle. This method may be applicable to various DC motors.

원적외선이 흰쥐의 생존율에 미치는 영향 (The effect of Far-infrared on survival rate of mice)

  • 김재윤;박승규;김진상;박래준
    • The Journal of Korean Physical Therapy
    • /
    • 제13권3호
    • /
    • pp.561-567
    • /
    • 2001
  • IR classified by wavelength three parts NIR, MIR. FIR. There is FIR which is radiated from healthy human body the wave length is 8-14m. The Sun's ray is composed of Infared(49%), Visible light(40%) and Ultra violet(11%), however the ray getting to the earth is FIR(60%), IR(20%), and UV(20%). Human beings has utilized FIR already from time immemorial. Hershel found out Infrared for the first time, in the Industrial Revolution the Infrared and FIR had been begun to use making products. FIR with low temperature can deeply penetrate on the human body composed things without troublesome, since FIR has effectively operated on the human body at low temperature (35-40 $^{\circ}$C). In this study, we experimented in the specific temperature FlR radiation intensity. water consumption rate, feed consumption rate. survival rate and mean of weight balance with FlR radiation instrument. According to the results, the FlR radiation to the mice assisted to increase the survival rate.

  • PDF

Far-Infrared의 발전사와 물리치료 적용에 대한 연구 (A Study of Far-Infrared History and Application to Physical Therapy)

  • 김재윤;박래준;박영한
    • The Journal of Korean Physical Therapy
    • /
    • 제13권1호
    • /
    • pp.189-195
    • /
    • 2001
  • The Sun's ray is composed of Infared(49%), Visible light(40%) and Ultra violet(11%), however the ray getting to the earth is FIR(60%). IR(20%), and UV(20%). Human beings has utilized FIR already from time immemorial. Hershel found out Infrared for the first time, in the Industrial Revolution the Infrared and FI R had been begun to use making products. In asia. also, asian already has made use of FIR to treat the body, product things and make warm the house in the winter, as it had been called Wull therapy, fermentation. and On-Dol system. In these days, with contemporary science FIR would be begun to clear up the implication in the human body and organic compounds. IR classified by wavelength three parts NIR, MIR, FIR. There is FIR which is radiated from healthy human body the wave length is 8-14 m. It is difficult to standardized the wavelength of IR, since each related associations have a different opinion, so we suggested ideal IR wavelength and biological, phsiotherapical, medical FIR wavelength.

  • PDF

다물체 동역학을 이용한 DC 모터 소음 저감에 관한 연구 (The Noise Reduction of A DC Motor Using Multi-body Dynamics)

  • 정일호;박태원;박지연
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2004년도 춘계학술대회
    • /
    • pp.875-880
    • /
    • 2004
  • The DC Motor of a vehicle may cause noise and vibration due to high-speed revolution, which can make a driver feel uncomfortable. There have been various studies that attempted to solve these problems, mostly focusing on the causes of noise and vibration and the means of preventing them. The CAE methodology is more efficient than a real test for the purpose of looking for various design parameters to reduce the noise and vibration of the DC motor. In this study, a design process for reducing brush noise is presented with the use of a computer model, which is made by using a multi-body dynamics program (DADS). The design parameters to reduce the brush noise and vibration were proposed using a computer model. They were used to reduce the noise and vibration of a DC motor and verified by the test results of a fan DC motor in a vehicle. This method may be applicable to various DC motors.

  • PDF

Cadmium에 대한 Metallothionein 및 Free Radical Scavenger에 관한 최근의 연구 동향 (Recent Research Trend on Free Radical Scavenger and Metallothioneins on Cadmium)

  • 김영숙;유대식
    • 동아시아식생활학회지
    • /
    • 제11권1호
    • /
    • pp.1-10
    • /
    • 2001
  • Since the Industrial Revolution, people have enjoyed an abundant life, owing to the technological innovations of science. However, because of changes in the environment or polution to the environment, it has brought on many chronic diseases. Especially, even though it may be a small amount, if cadmium gets into a human body, because its biological half life is long, it fatally causes a kidney disease and damage to human organisms. It was reported that Metallothioneins(MT), a substance that is closely related with a free radical that comes from environmental pollution and the course of which cadmium, which causes chronic addition in the body, is formed, along with harmful metals, make the toxicity reduce. MT compound led into the body by cadmium indirectly functions as an antioxidation, supplied adequate amount of vitamin E, and suppresses the accumulation of cadmium in heart, liver and blood. Cadmium content found in Korean soil according to the test conducted from 1992 to 1996 was 0.02~0.03mg/kg in cereals, pulses, and potatoes. Free radical scavenger, finding solution for metal substance that comes from environmental pollution from food and natural substances implicates a better future for the study of food science.

  • PDF

바이어스 드레이핑 디자인 연구(硏究) (A Study of Bias Draping Design)

  • 김희균;조규화
    • 패션비즈니스
    • /
    • 제4권4호
    • /
    • pp.1-16
    • /
    • 2000
  • The purpose of this study is to investigate the formative beauty, changes in fashion and aesthetical sense that can be seen in the bias drapings of Madeleine Vionnet and her influences on modern fashion since she used draping as a new fashion means to represent the new feminine images which modernism of the early 20th century and social changes from the two great World War's generated, and to provide proper data to encourage designers' creativity that is wanting in the circle of Korea fashion. Bias draping led women to respect worship their body from the heart with seductive modernism enriching the material's texture to the utmost through geometrical patterns of triangle, quartered plane and quardrants and simple cylindrical cuts and with an attribute adapting itself to the wearer's body. Bias draped wear consisted of light and transparent materials and overall surface decoration revealed women's movements and sought the extension of environmental movements and demonstrated its eroticism. On the other hand, biased daywear gained anonymity through cutting true to body line and psychological protective quality as of cape, and this went well with the independent femininity accepting difference as well as pursuing revolution from the inside. The great inflation and the 2nd World War gave birth to escape from reality like surrealistic artistic tendencies and Hollywood films and increased romanticism. Bias draping once underwent unpopularity except in expensive clothes due to knit wear boom and the utilization of new elastic materials, however, it began to receive lights again from pluralization waves and retro tendencies and to be introduced in many designers' collections. A young genius of England, John Galliano improved functions of Haute Couture through creation of new styles and fantastic shows to promote profits in the fashion markets. Bias draping fitted in human body line provides us comfort and aesthetic qualities through careful choice of material and elegance by delicate cutting.

  • PDF

Determination of Surface Currents on Circular Microstrip Antennas

  • Godaymi, Wa'il A.;Mohammed, Abdul-Kareem Abd Ali;Ahmed, Zeki A.
    • Journal of electromagnetic engineering and science
    • /
    • 제12권4호
    • /
    • pp.260-270
    • /
    • 2012
  • This work aims to present a theoretical analysis of the electric and magnetic surface current densities of a circular microstrip antenna (CMSA) as a body of revolution. The rigorous analysis of these problems begins with the application of the equivalence principle, which introduces an unknown electric current density on the conducting surface and both unknown equivalent electric and magnetic surface current densities on the dielectric surface. These current densities satisfy the integral equations (IEs) obtained by canceling the tangential components of the electric field on the conducting surface and enforcing the continuity of the tangential components of the fields across the dielectric surface. The formulation of the radiation problems is based on the combined field integral equation. This formulation is coupled with the method of moments (MoMs) as a numerical solution for this equation. The numerical results of the electric and magnetic surface current densities on the outside boundary of a CMSA excited by $TM_{11^-}$ and $TM_{21^-}$ modes are presented. The radiation pattern is calculated numerically in the two principle planes for a CMSA and gives a good results compared with measured results published by other research workers.

IoT 기반의 스마트 마스크 설계 및 구현 (Design and Implementation of Smart Mask based on IoT)

  • 왕이;김현기
    • 한국멀티미디어학회논문지
    • /
    • 제25권4호
    • /
    • pp.610-619
    • /
    • 2022
  • Recently, the market for masks has been growing due to air pollution, sun protection, pollen allergies and other reasons. In addition, the demand for masks has increased dramatically due to the new coronavirus from 2020, and masks are still one of the necessities of life. Although the reliance on masks is increasing, there are many inconveniences associated with wearing masks for long periods of time. At the same time, technology is developing rapidly, and the demand for smart wearable devices is increasing. Therefore, at the moment when the fourth industrial revolution is underway, combining people's common necessities with IoT technology to bring new convenient experiences to people is an important direction for future technology development and product development. In this study, smart masks were designed and implemented using IoT(Internet of Things) technology. The mask uses a microcomputer Adafruit circuit playground express, using the microcomputer's LED, optical sensors, can be in the dark place light, and through the temperature sensor real-time grasp of body temperature changes. If the body temperature rises above normal, the LED will turn "on" and activate the voice sensor to warn yourself and others around you.

롤러 위를 주행하는 벨트의 거동 (Behavior of Belt Running over the Rollers)

  • 윤여훈;윤준현
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2004년도 춘계학술대회논문집
    • /
    • pp.900-905
    • /
    • 2004
  • Development of color printer, postal classification machine, ATM and so on requires higher moving performance of the flat belt. Skew of the flat belt running over misaligned roller has a bad effect on performances of media transport. The vibration of loose side of belt causes the escape of the belt from roller and the drop of velocity of driven roller after the start of driving roller revolution. The skew of flat belt is investigated by FEM and dynamic simulation. FEM results show parameters which affect the skew of belt and match with dynamic results qualitatively. The shape of loose side of belt can be found by dynamic simulation. Increase of the acceleration time and initial tension have diminished the unstable movement of the loose side of belt.

  • PDF

A Simple Estimation of the Viscous Resistance of Ships by Wake Surveys

  • Shin-Hyoung,Kang;Beom-Soo,Hyun
    • 대한조선학회지
    • /
    • 제19권2호
    • /
    • pp.19-25
    • /
    • 1982
  • Several formulae have been proposed to estimate the viscous resistance of ships by wake surveys. Both the total head and the velocity should be measured. The integration of he total head loss shows over estimations of the resistance by about 10%. Therefore measurements of the velocity are required, which need much more works. A simple method is suggested in this paper to take accout of the velocity-defect from the measured total head. It gives reasonable estimations of the viscous resistance within the experimental accuracy. Experimental data of a low-drag body of revolution in the wind-tunnel and Series 60 model, CB=0.6 in the tank are used to verify the suggested formula.

  • PDF