• Title/Summary/Keyword: Dimensional Change Control

Search Result 200, Processing Time 0.029 seconds

The Ironies of Japan Going into Trousers

  • Cliffe, Sheila
    • The International Journal of Costume Culture
    • /
    • v.13 no.2
    • /
    • pp.160-168
    • /
    • 2010
  • This paper examines a particular period in Japanese history. when clothing was systemically changed through government policy. It demonstrates the complex relationships between an Eastern nation and a Western clothing system. It also explores the complexity of roles which clothing plays in society, clothing which brands a nation as masculine, but which resists the discourses of modernity, which were found on native clothing. It demonstrates that native, Japanese clothing has always been developing to meet the needs of its wearers, according to technology, sumptuary laws and prevailing tastes, and therefore that fashion is not any more a product of Europe than it is of the East. It reveals the Japanese fashion system as a complex and multi-dimensional one, about surface design rather than change in shape, bur also being about inner and deep surfaces as well as outer surfaces for public presentation, and thus being a carrier for private as well as public discourses. This examination also demonstrates that whilst fashion may be intimately bound up with the forces of society and also politics, it is also a force which resists outside control, and develops because of the signification with which the embodied wearers endow it.

  • PDF

A Study on the Improvement of Positioning accuracy of ultra-precision stage (초정밀스테이지의 위치결정정도 향상에 관한 연구)

  • 황주호;송창규;박천홍;이찬홍
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2001.04a
    • /
    • pp.465-468
    • /
    • 2001
  • An aerostatic stage has frictionless behavior, so it has a advantage of investigation into positioning characteristics. A one-dimensional aerostatic ceramic stage with ballscrew driven and laser scale feedback system is manufactured, aiming at investigating positioning characteristic of ultra-precision stage. We confirm, this ceramic aerostatic stage has a 10nm micro resolution, and can be reduced mean of position error by compensation of numeric control command. By means of analyzing relationship of position error and change of temperature, we build a on-line compensation algorithm of position error from the measured temperature data. So we can improve repeatability of ultra-precision stage up to 34%($0.095{\mu}$) of the normal condition.

  • PDF

Laser Beam Projection by Use of a Galvano-Mirror and Its Application to Holographic Memories (갈바노미러를 이용한 레이저 빔 투사 및 홀로그래픽 메모리에의 응용)

  • Park, Y.S.;Shin, D.H.;Ok, J.S.;Lee, J.H.;Jang, J.S.;Lee, W.C.
    • Journal of Power System Engineering
    • /
    • v.3 no.2
    • /
    • pp.79-83
    • /
    • 1999
  • We implemented a system that can change laser beam directions rapidly by controlling the galvano-mirror, on which a mirror is mounted, with a computer. We show that a laser projection can be realized by programming our system properly, and that it can also be used for multiplexing 2-dimensional image information in the data storage of holographic memories efficiently.

  • PDF

A Study of the Gas Flow through a Safety Valve for LNG Ship Engine (LNG 선박용 안전밸브를 지나는 기체유동에 관한 연구)

  • Lee, Jun-Hee;Kim, Heuy-Dong;Park, Kyung-Am
    • 유체기계공업학회:학술대회논문집
    • /
    • 2005.12a
    • /
    • pp.441-447
    • /
    • 2005
  • The present study is aimed at understanding the flow physics associated with a safety valve applied to LNG ship engines. One-dimensional gasdynamic analyses and axisymmetric, compressible Navier-Stokes computations have been carried out to provide a qualitative and quantitative knowledge base for an effective design of the safety valve. Gasdynamic forces and thrust coefficients are obtained regarding a change in chamber pressure and distance between the nozzle exit and valve sheet which are major parameters to offer a variation in the flow feature. The present results show that the control of the passage area between the nozzle exit and valve sheet can attenuate the strength of shockwave generated in front of the valve sheet, which causes harm to stable system operation.

  • PDF

Blast Furnace Modeling for Predicting Cohesive Zone Shape (융착대 예측을 위한 고로공정 모델링)

  • Yang, Kwang-Heok;Choi, Sang-Min;Jung, Jin-Kyung
    • 한국연소학회:학술대회논문집
    • /
    • 2006.04a
    • /
    • pp.39-45
    • /
    • 2006
  • Analysis of the internal state of the blast furnace is needed to predict and control the operating condition. Especially, it is important to develop modeling of blast furnace for predicting cohesive zone because shape of cohesive zone influences overall operating condition of blast furnace such as gas flow, chemical reactions and temperature. because many previous blast furnace models assumed cohesive zone to be fixed, they can't evaluate change of cohesive zone shape by operation condition such as PCR, blast condition, and production rate. In this study, an axi-symmetric 2-dimensional steady state model is proposed to simulate blast furnace process. In this model, cohesive zone is changed by solid temperature range, FVM is used for numerical simulation. To find location of cohesive zone whole calculation procedure is iterated Until cohesive zone is converged. Through this approach, shape of cohesive zone, velocity, composition and temperature within the furnace are predicted by model.

  • PDF

Optimization of Process Variables in Copper Infiltration of Low and High Density Ferrous Structural Parts

  • Joys, Jessu;Luk, Sydney
    • Proceedings of the Korean Powder Metallurgy Institute Conference
    • /
    • 2006.09b
    • /
    • pp.826-827
    • /
    • 2006
  • Copper infiltration is demonstrated as a viable solution to achieve higher mechanical properties by filling the interconnected porosities of a ferrous structure with copper infiltrant. This paper will present the results of a design of experiments study based on the selected processing variables in the copper infiltration process. The variables are the following: Infiltrating temperatures, infiltrating time at pre-heat zone and hot zone, the green density of iron part, the migration of copper into the iron part at different processing conditions. The results show the flexibility of the infiltration process to attain certain mechanical properties by changing the processing conditions.

  • PDF

Morphology Control of Single Crystalline Rutile TiO2 Nanowires

  • Park, Yi-Seul;Lee, Jin-Seok
    • Bulletin of the Korean Chemical Society
    • /
    • v.32 no.10
    • /
    • pp.3571-3574
    • /
    • 2011
  • Nano-scaled metal oxides have been attractive materials for sensors, photocatalysis, and dye-sensitization for solar cells. We report the controlled synthesis and characterization of single crystalline $TiO_2$ nanowires via a catalyst-assisted vapor-liquid-solid (VLS) and vapor-solid (VS) growth mechanism during TiO powder evaporation. Scanning electron microscope (SEM) and transmission electron microscope (TEM) studies show that as grown $TiO_2$ materials are one-dimensional (1D) nano-structures with a single crystalline rutile phase. Also, energy-dispersive X-ray (EDX) spectroscopy indicates the presence of both Ti and O with a Ti/O atomic ratio of 1 to 2. Various morphologies of single crystalline $TiO_2$ nano-structures are realized by controlling the growth temperature and flow rate of carrier gas. Large amount of reactant evaporated at high temperature and high flow rate is crucial to the morphology change of $TiO_2$ nanowire.

Investigate on the rate of change of CO concentration in a tunnel under changed position of the jet fans by using numerical method (제트 팬 가동위치에 따른 장대터널 내 CO 농도 변화율에 대한 전산해석)

  • Min, Jae-Hong;Kim, Dae-Hyun;Chung, Jin-Taek
    • Proceedings of the KSME Conference
    • /
    • 2008.11b
    • /
    • pp.2765-2770
    • /
    • 2008
  • The purpose of tunnel ventilation system for long road tunnels is to keep certain levels of Visibility Index and the concentration of CO. Additional equipments such as jet fans are used in road tunnel to discharge pollutants in the road tunnel. The control algorism of tunnel ventilation system takes the value of sensors as input, and then gives the operation method of jet fans in tunnel as output. Information on the variation of CO concentration in tunnel when jet fans are running is needed to minimize their operation time. Numerical analysis is used in this paper because of the difficulty of conducting experiments under standard condition for ventilation of road tunnel. The concentration of CO has been calculated by using 3-dimensional CFD under transient condition with speed of cars, quantity of air ventilation, and the results for various operation position of jet fans are compared.

  • PDF

A Combustion Instability Analysis of a Model Gas Turbine Combustor by the Transfer Matrix Method

  • Cha, Dong-Jin;Kim, Jay-H.;Joo, Yong-Jin
    • Proceedings of the KSME Conference
    • /
    • 2008.11b
    • /
    • pp.2946-2951
    • /
    • 2008
  • Combustion instability is a major issue in design of gas turbine combustors for efficient operation with low emissions. Combustion instability is induced by the interaction of the unsteady heat release of the combustion process and the change in the acoustic pressure in the combustion chamber. In an effort to develop a technique to predict self-excited combustion instability of gas turbine combustors, a new stability analysis method based on the transfer matrix method is developed. The method views the combustion system as a one-dimensional acoustic system with a side branch and describes the heat source as the input to the system. This approach makes it possible to use the advantages of not only the transfer matrix method but also well-established classic control theories. The approach is applied to a simple gas turbine combustion system to demonstrate the validity and effectiveness of the approach.

  • PDF

Performance sensitivity analysis of feedback system for adaptive control of a vehicle suspension (자동차 현가장치의 적응제어를 위한 feedback 시스템의 성능감도 해석)

  • Park, H;Jeon, E. S.;Oh, J. E.
    • Journal of the korean Society of Automotive Engineers
    • /
    • v.13 no.1
    • /
    • pp.35-45
    • /
    • 1991
  • A linear quarter model of a vehicle suspension system is built and simulated. Especially the so-called sensitivity analysis is conducted in order to show its applicability to design problems, and sensitivity function is determined in the frequency domain. The change of frequency response function is predicted, which depends on the design parameter variation and the property is verified by computer simulation. Typical performance measures, namely, sprung mass acceleration, suspension deflection, and tire deflection are examined. The vehicle model is analyzed for ist performance sensitivity as a function of the system's feedback gains. The variable feedback gains are selected as the spring and damping coefficients. Frequency response, RMS response, and performance index of the performance evaluation variables are considered and three-dimensional and contour plots of response surfaces are formed to examine output sensitivity to suspension feedback. Performance trade-offs over the entire frequency spectrum are identified from the FRF, and that between ride quality and handling characteristics are examined from the RMS responses.

  • PDF