• Title/Summary/Keyword: Various temperature

Search Result 12,828, Processing Time 0.043 seconds

A Study on the Distribution of Temperature by Moving Heat Source during Welding (용접중 이동하는 열원에 의한 온도분포에 관한 연구)

  • 왕지석
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.6 no.2
    • /
    • pp.51-68
    • /
    • 1982
  • A method of calculation of temperature distribution during welding was studied and compared with the existing formulas and experimental results. In contrast to the existing formulas which are founded on the suppositions that the heat source is a point and that the dimensions of welded pieces are infinite, we tried to make the distribution of calorific density of heat source approach reality more closely, so we considered it as a normal distribution of Gauss, and we presented the formulas for calculation of temperature during welding. We also used the principle of superposition for the temperature calculations of finite welded pieces. We compared the formulas presented in this paper with the existing formulas by calculations for the welding of various materials, and considerable differences around the heat source were convinced. The thermal cycles of various points were traced through the welding experiments for the mild steel, and they were compared with the results of calculations.

  • PDF

A Study on the Dyeing Properties of Silk and Cotton Fabrics with Chestnut Bur Extract(2) (밤송이 추출액을 이용한 견과 면직물 염색 (2))

  • Kim, Ae Sun;Jang, Jae Cheol
    • Textile Coloration and Finishing
    • /
    • v.13 no.2
    • /
    • pp.7-7
    • /
    • 2001
  • This paper investigated the dyeability and surface color of silk and cotton fabrics dyed with chustnut bur extract. Some experiments were performed under the various dyeing conditions such as dyeing temperature, dyeing time, repetition of dyeing, dyeing pH, mordanting condition, washing fastness and light fastness with silk and cotton fabrics. The results obtained were as follows 1. △E value was increased when dyeing temperature and time was higher, value of munsell was shifted from Yellow to Yellow-Red at hither dyeing temperature and time in silk and cotton fabrics. 2. Optimal dyeing pH was increased with acidity of dyeing solution in silk and cotton fabrics, and repetition of dyeing did not change the dye-uptake. 3. When mordanting time and temperature was higher, △E value was larger in silk and cotton fabrics. Silk and cotton fabrics with Fe-premordanting treatment had best dyeability, but treatment with Sn-mordanting was worst. 4. Washing fastness and light fastness was excellent in various dyeing condition at silk fabric but cotton was without practical use.

A Study on the Dyeing Properties of Silk and Cotton Fabrics with Chestnut Bur Extract(2) (밤송이 추출액을 이용한 견과 면직물 염색 (2))

  • 김애순;장재철
    • Textile Coloration and Finishing
    • /
    • v.13 no.2
    • /
    • pp.93-103
    • /
    • 2001
  • This paper investigated the dyeability and surface color of silk and cotton fabrics deed with chustnut bur extract. Some experiments were performed under the various dyeing conditions such as dyeing temperature, dyeing time, repetition of dyeing, dyeing pH, mordanting condition, washing fastness and light fastness with silk and cotton fabrics. The results obtained were as follows 1. $\Delta{E}$ value was increased when dyeing temperature and time was higher, value of munsell was shifted from Yellow to Yellow-Red at hither dyeing temperature and time In silk and cotton fabrics. 2. Optimal dyeing pH was increased with acidity of dyeing solution in silk and cotton fabrics, and repetition of dyeing did not change the dye-uptake. 3. When mordanting time and temperature was higher, $\Delta{E}$ value was larger in silk and cotton fabrics. Silk and cotton fabrics with Fe-premordanting treatment had best dyeability, but treatment with Sn-mordanting was worst. 4. Washing fastness and light fastness was excellent in various dyeing condition at silk fabric but cotton was without practical use.

  • PDF

Developmemt of automobile sensor monitoring system (자동차 센서 모니터링 시스템 개발)

  • Choi, Nakg-Won;Lee, Sang-Hoon
    • Journal of Sensor Science and Technology
    • /
    • v.14 no.3
    • /
    • pp.150-155
    • /
    • 2005
  • We propose a newly developed automobile sensor monitoring system incorporated with a tire pressure monitoring sensor(TPMS). The RF-transmitter based on a tire pressure sensor, sends a frame data about measured tire-pressure to RF receiver. And the various sensing signals based on sensors such as fuel-level sensor, engine oil level sensor and temperature sensors, are converted into 10-bit digital data. The microprocessor displays converting data such as tire pressure, trip distance, fuel quantity, coolant temperature and car-room temperature, on LCD panel. The proposed system can be successfully adapted to monitoring of the tire pressure and various automobile sensors.

Image Correction Method for Uncooled IR TECless Detector with Non-linear characteristics due to Temperature Change

  • Shin, Jung-Ho;Ye, Seong-Eun;Kim, Bo-Mee;Park, Chan
    • Journal of the Korea Society of Computer and Information
    • /
    • v.22 no.10
    • /
    • pp.19-26
    • /
    • 2017
  • In this paper, we propose an efficient image equipment implementation for the detector characteristics of various detectors by analyzing un-cooled thermal detector that exhibits nonlinear changes due to external temperature effects. First, we explain Thermal Electric Cooler for un-cooled detector temperature control system and Non-image correction methode for IR system. Second, we present the results of a study on an efficient control technique that can minimize the deterioration of image quality by controlling a un-cooled thermal detector without a thermal electric cooler(TEC) inside. Third, we suggest Image Correction Methods for Uncooled IR TECless Detector with Non-linear characteristics due to Temperature Change. So, we analyze and present the results of Image correction methods for various un-cooled thermal detector.

Modeling of a Greenhouse Equipped with Latent Heat Storage System (잠열축열 장치를 갖춘 온실의 난방 열 특성 예측모형개발)

  • Ro, J.G.;Song, H.K.
    • Journal of the Korean Solar Energy Society
    • /
    • v.21 no.3
    • /
    • pp.51-60
    • /
    • 2001
  • A greenhouse equipped with latent heat storage system was built to obtain various thermal properties, such as greenhouse air temperature, soil surface temperature, energy flow in latent heat storage, etc., which could be used in validation of greenhouse numerical model to be developed in this study. This numerical model expressed with Newton-Raphson method was programed by C-language and utilized to simulate greenhouse thermal behavior. Greenhouse air temperature and soil surface temperature predicted by the greenhouse model developed in this study were very close to the measured data obtained through almost 3 years of experiment. Therefore, it is concluded that the greenhouse model developed and verified by measured data could be utilized for simulating various thermal behaviors of greenhouses equipped with latent heat storage system to be used for energy saving purposes.

  • PDF

Structural and Electrical Properties of Bismuth Magnesium Niobate Thin Films deposited at Various Temperatures

  • Park, Jong-Hyun;Yoon, Soon-Gil
    • Transactions on Electrical and Electronic Materials
    • /
    • v.8 no.4
    • /
    • pp.153-156
    • /
    • 2007
  • Structural and electrical properties of the fully crystallized-bismuth magnesium niobate ($Bi_2Mg_{2/3}Nb_{4/3}O_7$, BMN) films with 15 mol% excess bismuth deposited on Pt bottom electrode by pulsed laser deposition are characterized for various deposition temperatures. The BMN films were crystallized with a monoclinic structure from $300^{\circ}C$ and the surface roughness slightly decreases with increasing deposition temperature. The capacitance density of the films increases with increasing deposition temperature and especially, films deposited at $400^{\circ}C$ exhibit a capacitance density of approximately $620nF/cm^2$. The crystallized BMN films with approximately 170 nm thickness exhibit breakdown strength above 600 kV/cm (${\leq}10V$) irrespective of deposition temperature and a leakage current density of approximately $2{\times}10^{-8}A/cm^2$ at 590kV/cm (at 10 V).

Fundamental Research of Early Frozen Damage on Concrete Depending on Various Time Periods of -20℃ Temperature Condition (외기온 -20℃의 유지시간 변화에 따른 초기동해 피해의 기초적 연구)

  • Choi, Yoon-Ho;Han, Jun-Hui;Lee, Young-Jun;Hyun, Seung-Yong;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2019.05a
    • /
    • pp.197-198
    • /
    • 2019
  • The aim of the research is evaluating the feasibility of inspection for early age frozen damage and for expansion of concrete under the various time periods of -20℃ temperature condition. When the concrete samples were exposed for 12 hours and 24 hours, the frozen depth of the concrete were 10 and 60 mm, respectively, under the wet conditions. From the experiment results of temperature and expansion, only surface area suffered frozen damage for 12 hours exposing conditions while entire area suffered frozen damage for 24 hours exposing conditions.

  • PDF

EFfect of Molding Temperature and Debinding Conditions on Fabrication of Alumina Component by Injection Molding (금형온도와 탈지조건이 사출성형에 의한 알루미나 부품 제조에 미치는 영향)

  • 임형택;임대순
    • Journal of the Korean Ceramic Society
    • /
    • v.32 no.5
    • /
    • pp.559-566
    • /
    • 1995
  • Alumina powder was coated with stearic acid and then mixed with isotactic polypropylene, atactic polypropylene as binders at 15$0^{\circ}C$ for 2 hours. The mixture was then injection molded at various mold temperatures using injection molding machine to investigate the effect of the molding temperature and debinding parameters on the formation of the defects. The molded specimens were debinded in both air and nitrogen atmospheres. Wicking and solvent methods were also used to enhance debinding efficiency. The specimens were prefired at 120$0^{\circ}C$ and then sintered at 150$0^{\circ}C$ for 3 hours. Various defects were formed at mold temoperature of 3$0^{\circ}C$, 6$0^{\circ}C$ and 10$0^{\circ}C$ and any noticeable defect was not formed at 85$^{\circ}C$. The density of green body increased with mold temperature. Debinding in air atmosphere was more effective than in nitrogen atmosphere. Results also proved that wicking and solvent treatments helped minimize the number of defects.

  • PDF

Simple modeling to explore temperatures, heated temperature, and Kappa values of a current sheet observation

  • Lee, Jin-Yi;Raymond, John C.;Reeves, Katharine K.;Shen, Chengcai;Kahler, Stephen;Moon, Yong-Jae;Kim, Yeon-Han
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.46 no.2
    • /
    • pp.79.2-79.2
    • /
    • 2021
  • We explore the range of possibilities of temperatures, heated temperature, and Kappa values of a current sheet observation on 2017 September 10. First, we construct a grid model with rapid heating (Theat) and various Kappa (κ) values. We assume a simple density model and use adiabatic cooling to set the temperature during expansion. Next, we calculate the ion fractions using a time-dependent ionization model with adiabatic cooling and various Kappa values. The calculated ion fractions are used to simulate the DNs of the Atmospheric Imaging Assembly on board the Solar Dynamic Observatory. Then, we explore the possible range of the temperatures and Kappa values, comparing the simulated images with the observations. Finally, we discuss the range of the heated temperature and Kappa values and whether the result of this study suggests continuous heating of the current sheet plasma during the expansion.

  • PDF