• Title/Summary/Keyword: Medium temperature

Search Result 2,601, Processing Time 0.033 seconds

Simultaneous Measurement of Temperature and Refractive Index of a Medium Using by a Side-Polished Fiber Containing a Fiber Bragg Grating (광섬유 브래그 격자가 포함된 측면 연마된 광섬유를 이용한 매질의 온도와 굴절률 동시 측정)

  • Kim, Kwang Taek
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.28 no.8
    • /
    • pp.513-517
    • /
    • 2015
  • We proposed and demonstrated a simultaneous measurement method to detect the refractive index and temperature of a medium using a side-polished fiber involving FBG (fiber Bragg grating). The temperature of a medium was obtained by using the Bragg wavelength shift of FBG, while the refractive index of medium were calculated by using the transmission loss. The Bragg wavelength is independent on the refractive index of the covering medium placed on surface of side-polished fiber, while the transmission loss at off-Bragg wavelength highly depends on the environmental temperature because of thermo-optic effect of the medium.

The Research on the Indoor Temperature and Humidity Control of Green Roof by Solid Growing Medium in Summer (고형화된 식생기반재를 활용한 여름철 옥상녹화의 실내 온·습도 조절효과 연구)

  • Lee, Hyun-Jung;Yeom, Dongwoo;Lee, Kyu-In
    • KIEAE Journal
    • /
    • v.15 no.3
    • /
    • pp.93-99
    • /
    • 2015
  • Purpose: Various studies on the soil-based green roof systems have been conducted, and a lot of green roof systems were developed. A growing medium board is one of them which was developed for better application and maintenance, however the effect and performance of this material need to be verified. On this background, the purpose of this study is to prove cooling load reduction of green roof by monitoring experiment on the full-scale mock-ups. Method: To do this, Solid growing medium boards were installed on the mock-ups, and indoor temperature and humidity were monitored and analyzed. Result: As a results, the green roof with solid growing medium board were verified effective for controlling indoor temperature in summer.

A Study on the medium seepage and the fracture connectivity by using temperature monitoring with thremal line sensors (온도센서 배열 모니터링에 의한 매질의 투수성 및 절리 연결성 연구)

  • Kim, Jung-Yul;Kim, Tae-Hee;Kim, Yoo-Sung
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2006.03a
    • /
    • pp.1110-1119
    • /
    • 2006
  • If water flows through a narrow passage into a medium that keeps the equilibrium of temperature, it causes small temperature difference and makes a temperature anomaly. The seepage or leakage often observed at old dams is a representative example of bringing about a temperature anomaly. Therefore, temperature measurements have been regarded as one of excellent methods that can detect the situation of seepage or leakage. However, because existing temperature measurement methods are based on a single sensor, the application of the method to the whole structure is nearly not possible in technical and economical phases. This paper introduces a temperature monitoring system using a thermal sensor cable that is comprised of addressable thermal sensors connected in parallel at many positions within a single cable. Through various laboratory and field experiments, it has been proved that the temperature monitoring technique can give an useful information about permeability of a medium or connectivity of fractures which have been regarded as difficult problems.

  • PDF

Methods of temperature measurement of medium in bottle during sterilization (병재배 배지살균 시 배지내부의 실시간 온도측정 방법)

  • Cheong, Jong-Chun;Jhune, Chang-Sung;Lee, Chan-Jung;Oh, Jin-A;Shin, Pyeong-Gyun
    • Journal of Mushroom
    • /
    • v.9 no.2
    • /
    • pp.74-79
    • /
    • 2011
  • This study was carried out to develop a method related to measuring the temperature of sterile medium in bottle cultivation. When the medium is sterilized, the device is able to be inserted inside of the medium and the temperature can be directly measured in real time although high temperature and pressure are detected in the sterilization. This device can be able to measure the sterilization temperature in short intervals inside of autoclave and medium used in bottle cultivation. As the method were applied to the field cultivation of mushroom, we could produce mushroom in consistent manner through the optimum sterilization of the medium.

Effect of Intercritical Annealing on Microstructure and Mechanical Properties of Fe-9Mn-0.2C-3Al-0.5Si Medium Manganese Steels Containing Cu and Ni (구리와 니켈이 포함된 Fe-9Mn-0.2C-3Al-0.5Si 중망간강의 미세조직과 기계적 특성에 미치는 2상역 어닐링의 영향)

  • Lee, Seung-Wan;Sin, Seung-Hyuk;Hwang, Byoungchul
    • Korean Journal of Materials Research
    • /
    • v.30 no.1
    • /
    • pp.44-49
    • /
    • 2020
  • The effect of intercritical annealing temperature on the microstructure and mechanical properties of Fe-9Mn-0.2C-3Al-0.5Si medium manganese steels containing Cu and Ni is investigated in this study. Six kinds of medium manganese steels are fabricated by varying the chemical composition and intercritical annealing temperature. Hardness and tensile tests are performed to examine the correlation of microstructure and mechanical properties for the intercritical annealed medium manganese steels containing Cu and Ni. The microstructures of all the steels are composed mostly of lath ferrite, reverted austenite and cementite, regardless of annealing temperature. The room-temperature tensile test results show that the yield and tensile strengths decrease with increasing intercritical annealing temperature due to higher volume fraction and larger thickness of reverted austenite. On the other hand, total and uniform elongations, and strain hardening exponent increase due to higher dislocation density because transformation-induced plasticity is promoted with increasing annealing temperature by reduction in reverted austenite stability.

Nonlinear higher order Reddy theory for temperature-dependent vibration and instability of embedded functionally graded pipes conveying fluid-nanoparticle mixture

  • Raminnea, M.;Biglari, H.;Tahami, F. Vakili
    • Structural Engineering and Mechanics
    • /
    • v.59 no.1
    • /
    • pp.153-186
    • /
    • 2016
  • This paper addresses temperature-dependent nonlinear vibration and instability of embedded functionally graded (FG) pipes conveying viscous fluid-nanoparticle mixture. The surrounding elastic medium is modeled by temperature-dependent orthotropic Pasternak medium. Reddy third-order shear deformation theory (RSDT) of cylindrical shells are developed using the strain-displacement relations of Donnell theory. The well known Navier-Stokes equation is used for obtaining the applied force of fluid to pipe. Based on energy method and Hamilton's principal, the governing equations are derived. Generalized differential quadrature method (GDQM) is applied for obtaining the frequency and critical fluid velocity of system. The effects of different parameters such as mode numbers, nonlinearity, fluid velocity, volume percent of nanoparticle in fluid, gradient index, elastic medium, boundary condition and temperature gradient are discussed. Numerical results indicate that with increasing the stiffness of elastic medium and decreasing volume percent of nanoparticle in fluid, the frequency and critical fluid velocity increase. The presented results indicate that the material in-homogeneity has a significant influence on the vibration and instability behaviors of the FG pipes and should therefore be considered in its optimum design. In addition, fluid velocity leads to divergence and flutter instabilities.

Visualization of Temperature Elevation Due to Focused Ultrasound in Dissipative Acoustic Medium (음향감쇠매질 내에서 집속초음파에 의한 온도상승의 가시화)

  • Kim, Myoungseok;Kim, Jungsoon;Kim, Moojoon;Ha, Kanglyeol
    • The Journal of the Acoustical Society of Korea
    • /
    • v.33 no.1
    • /
    • pp.21-30
    • /
    • 2014
  • The temperature change due to focused ultrasound in dissipative acoustic medium is very important because it provides us much information. To measure the temperature change inside of the dissipative acoustic medium non-invasively, we adopt a temperature sensitive film which has thermochromic particles with critical temperature of $30^{\circ}C$. As a dissipative acoustic medium, agar layer is chosen in the study. The temperature change due to the ultrasound was measured depending on the concentration of the sugar in the agar layer. The color change on the film due to the ultrasound was investigated when the concentration of sugar was from 25% to 40%. As the result, there were rapid increases of discolored area on the film within 2~5 second after the ultrasound driving and the increasing rates decreased after the period. To compare the simulation results were also shown. However in the simulated result, the discolored areas linearly increased from start to 10 seconds. The reason of the differences between the experimental results and simulated ones is that the change of thermal conductivity and heat capacity of the medium were not considered in the simulation program.

Buckling of sandwich plates with FG-CNT-reinforced layers resting on orthotropic elastic medium using Reddy plate theory

  • Shokravi, Maryam
    • Steel and Composite Structures
    • /
    • v.23 no.6
    • /
    • pp.623-631
    • /
    • 2017
  • Present paper deals with the temperature-dependent buckling analysis of sandwich nanocomposite plates resting on elastic medium subjected to magnetic field. The lamina layers are reinforced with carbon nanotubes (CNTs) as uniform and functionally graded (FG). The elastic medium is considered as orthotropic Pasternak foundation with considering the effects of thermal loading on the spring and shear constants of medium. Mixture rule is utilized for obtaining the effective material properties of each layer. Adopting the Reddy shear deformation plate theory, the governing equations are derived based on energy method and Hamilton's principle. The buckling load of the structure is calculated with the Navier's method for the simply supported sandwich nanocomposite plates. Parametric study is conducted on the combined effects of the volume percent and distribution types of the CNTs, temperature change, elastic medium, magnetic field and geometrical parameters of the plates on the buckling load of the sandwich structure. The results show that FGX distribution of the CNTs leads to higher stiffness and consequently higher buckling load. In addition, considering the magnetic field increases the buckling load of the sandwich nanocomposite plate.

Influence of variable thermal conductivity on waves propagating through thermo-elastic medium

  • Abo-Dahab, Sayed M.;Jahangir, Adnan;Dar, Adiya
    • Structural Engineering and Mechanics
    • /
    • v.82 no.4
    • /
    • pp.459-467
    • /
    • 2022
  • We investigated the influence of variable thermal conductivity on waves propagating through the elastic medium. Infinitesimal deformation results in generation of thermal signal, and is analyzed by using dual phase lag heat (DPL) conduction model. The medium considered is homogenous, isotropic and bounded by thermal shock. The elastic waves propagating through the medium are considered to be harmonic in nature, and expressions for the physical variables are obtained accordingly. Analytically, we obtained the expressions for displacement components, temperature, micro-temperature component and stresses. The theoretical results obtained are computed graphically for the particular medium by using MATLAB.

Effect of Low Adapted Temperature and Medium Composition on Growth and Erythropoietin (EPO) Production by Chinese Hamster Ovary Cells

  • Kim Na Young;Kim Jung Hoe;Kim Hong Jin
    • Archives of Pharmacal Research
    • /
    • v.28 no.2
    • /
    • pp.220-226
    • /
    • 2005
  • Temperature and medium composition were changed with the aim of increasing growth and erythropoietin (EPO) production in EPO-producing Chinese hamster ovary (CHO) cells. We used the CHO cell line, IBE, and its derivative, CO5, which over-expresses the first two enzymes of the urea cycle, carbamoyl phosphate synthetase I (CPS I) and ornithine transcar-bamoylase (OTC). When supplements were added to the medium at $33\;^{\circ}C$, the growth of IBE and CO5 cells increased by $27\%\;and;26\%$, respectively and the maximum yield of EPO was increased by $40\%$ in both cell lines. The absolute EPO concentration in the CO5 cells was always $55{\sim}60\%$ higher than in the IBE cells. In addition, when the two cell lines were continuously cultured with supplements at $33\;^{\circ}C$ until their growth rates approached those at $37\;^{\circ}C$, the growth rates of both IBE and CO5 cells increased by $54\%$ and their maximum EPO levels increased by up to $73\%\;and\;56\%$, respectively. Therefore, the growth and EPO expression levels of CO5 cells increased 2.2-fold and 2.6-fold, respectively, compared to those of the IBE cells. These results indicate that adaptation to lower temperature as well as medium supplementation could be important for improving cell growth and EPO production.