• Title/Summary/Keyword: Temperature Profile

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Analysis of Transmission Infrared Laser Bonding for Polymer Micro Devices (폴리머 마이크로 장치에 대한 레이저 투과 마이크로 접합)

  • Kim, Joo-Han;Shin, Ki-Hoon
    • Journal of Welding and Joining
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    • v.23 no.5
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    • pp.55-60
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    • 2005
  • A precise bonding technique, transmission laser bonding using energy transfer, for polymer micro devices is presented. The irradiated IR laser beam passes through the transparent part and absorbed on the opaque part. The absorbed energy is converted into heat and bonding takes place. In order to optimize the bonding quality, the temperature profile on the interface must be obtained. Using optical measurements of the both plates, the absorbed energy can be calculated. At the wavelength of 1100nm $87.5\%$ of incident laser energy was used for bonding process from the calculation. A heat transfer model was applied for obtaining the transient temperature profile. It was found that with the power of 29.5 mW, the interface begins to melt and bond each other in 3 sec and it is in a good agreement with experiment results. The transmission IR laser bonding has a potential in the local precise bonding in MEMS or Lab-on-a-chip applications.

ANALYSIS OF THE ANODIC OXIDATION OF SINGLE CRYSTALLINE SILICON IN ETHYLEN GLYCOL SOLUTION

  • Yuga, Masamitsu;Takeuchi, Manabu
    • Journal of the Korean institute of surface engineering
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    • v.32 no.3
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    • pp.235-238
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    • 1999
  • Silicon dioxide films were prepared by anodizing silicon wafers in an ethylene $glycol+HNO_3(0.04{\;}N)$ at 20 to $70^{\circ}C$. The voltage between silicon anode and platinum cathode was measured during this process. Under the constant current electrolysis, the voltage increased with oxide film growth. The transition time at which the voltage reached the predetermined value depended on the temperature of the electrolyte. After the time of electrolysis reached the transition time, the anodization was changed the constant voltage mode. The depth profile of oxide film/Si substrate was confirmed by XPS analysis to study the influence of the electrolyte temperature on the anodization. Usually, the oxide-silicon peaks disappear in the silicon substrate, however, this peak was not small at $45^{\circ}C$ in this region.

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Interaction of casson nanofluid with Brownian motion: Temperature profile with shooting method

  • Iqbal, Waheed;Jalil, Mudassar;Khadimallah, Mohamed A.;Hussain, Muzamal;Naeem, Muhammad N.;Al Naim, Abdullah F.;Tounsi, Abdelouahed
    • Advances in nano research
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    • v.10 no.4
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    • pp.349-357
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    • 2021
  • In present study, the numerical investigations are carried out for effects of suction and blowing on boundary layer slip flow of casson nano fluid along permeable stretching cylinder in an exponential manner. The modeled PDEs are changed into nonlinear ODEs through appropriate nonlinear transformations. Change in physical quantities like friction coefficient, Nusselt and Sherwood numbers with variation of the aforementioned parameters are also examined and their numerical values are listed in the form of tables. Effects of Reynold number, suction parameter, Prandtl number, Lewis number, Brownian motion parameter and thermophoresis parameter are seen graphically with temperature profile.

In situ monitoring-based feature extraction for metal additive manufacturing products warpage prediction

  • Lee, Jungeon;Baek, Adrian M. Chung;Kim, Namhun;Kwon, Daeil
    • Smart Structures and Systems
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    • v.29 no.6
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    • pp.767-775
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    • 2022
  • Metal additive manufacturing (AM), also known as metal three-dimensional (3D) printing, produces 3D metal products by repeatedly adding and solidifying metal materials layer by layer. During the metal AM process, products experience repeated local melting and cooling using a laser or electron beam, resulting in product defects, such as warpage, cracks, and internal pores. Such defects adversely affect the final product. This paper proposes the in situ monitoring-based warpage prediction of metal AM products with experimental feature extraction. The temperature profile of the metal AM substrate during the process was experimentally collected. Time-domain features were extracted from the temperature profile, and their relationships to the warpage mechanism were investigated. The standard deviation showed a significant linear correlation with warpage. The findings from this study are expected to contribute to optimizing process parameters for metal AM warpage reduction.

Heat Transfer Analysis in a Straight Fin of Trapezoidal Profile by the Heat Balance Integral Method (열평형적분법에 의한 사다리꼴단면의 직선휜에서의 열전달해석)

  • Jo Jong-Chull;Cho Jin-Ho
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.11 no.3
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    • pp.1-8
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    • 1982
  • When exact analytical solutions to certain type of heat conduction problems are quite cumbersome or not obtainable, it is important to introduce approximate analytical methods which are simple and useful compared with numerical methods. In this study, therefore, the Heat Balance Integral Method is applied to analysis of steady-state conduction in a straight fin of trapezoidal profile, and the two-dimensional temperature distribution in the fin and the approximate fin efficiency are obtained. Results are compared with those by the one- dimensional analysis and two-dimensional numerical analysis for a wide range of Biot numbers. It is shown that the two-dimensional temperature distribution obtained by the integral method is in good agreement with that by the finite element method at Biot numbers for which the result by the one-dimensional analysis is unreliable.

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Temperature profile in the laminar lifted flame (부상화염 내부의 온도분포)

  • An, Hee Sung;Lee, Byeong Jun;Park, Chul-Woung;Park, Seung-Nam
    • 한국연소학회:학술대회논문집
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    • 2014.11a
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    • pp.357-358
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    • 2014
  • Coherent anti-Stokes Raman spectroscopy is one of the best tools to measure temperature distributions in the flame. Since it does not disturb the flow field, it could be used to study anchoring mechanism especially in the lifted flame. However, the length of probe volume is, normally, much greater than flame thickness. This weak point was overcome with lens combination in this study. It was found out that no peculiar temperature changes was happened near tribrachial point and heat transfer to the upstream was minimal near the flame anchoring position.

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Experimental Study on Temperature Profile Following Control (온도궤적 추종제어에 관한 실험적 연구)

  • Yoon, Seok-Young;Song, Tae-Seung;Yoon, Gun
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.239-239
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    • 2000
  • This paper present experimental results on temperature trajectory tracking. The benefits of precalculated feedforward input together with PID feedback control are demonstrated by experimental results. To find the feedforward input, the plant (autoregresiive) model is first identified and convex optimization procedure is applied. PID controller is then implemented based on Ziegler-Nickels tuning rule to reduce effects of disturbances and modeling errors. Experimental results show an improvement in slope tracking performance over the fully PID controller.

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Numerical Simulation: Effects of Gas Flow and Heat Transfer on Polymer Deposition in a Plasma Dry Etcher

  • Joo, Junghoon
    • Applied Science and Convergence Technology
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    • v.26 no.6
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    • pp.184-188
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    • 2017
  • Polymer deposition pattern on the ceramic lid surface is analyzed by numerical modeling. Assumption was made that is affected by gas flow pattern from the horizontal and vertical nozzles, temperature profile from the finger-like branches made of graphite and electrostatic potential effect. Calculated results showed gas flow dynamics is less relevant than two others. Temperature and electrostatic effects are likely determining the polymer deposition pattern based on our numerical simulation results.