• Title/Summary/Keyword: High Flow Rate

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Difference of Facial Skin Temperature Responses between Fear and Joy (공포와 기쁨 정서 간 안면온도 반응의 차이)

  • Eum, Yeong-Ji;Eom, Jin-Sup;Sohn, Jin-Hun
    • Science of Emotion and Sensibility
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    • v.15 no.1
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    • pp.1-8
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    • 2012
  • There have been many emotion researches to investigate physiological responses on specific emotions with physiological parameters such as heart rate, blood volume flow, and skin conductance. Very few researches, however, exists by detecting them with facial skin temperature. The purpose of present study was to observe the differences of facial skin temperature by using thermal camera, when participants stimulated by monitor scenes which could evoke fear or joy. There were totally 98 of participants; undergraduate students who were in their adult age and middle, high school students who were in their adolescence. We measured their facial temperature, before and after presenting emotional stimulus to see changes between both times. Temperature values were extracted in these regions; forehead, inner corners of the eyes, bridge of the nose, end of the nose, and cheeks. Temperature values in bridge and end of the nose were significantly decreased in fear emotion stimulated. There was also significant temperature increase in the area of forehead and the inner corners of the eyes, while the temperature value in end of the nose decreased. It showed decrease in both stimulated fear and joy. These results might be described as follows: When arousal level going up, sympathetic nervous activity increases, and in turn it makes blood flow in peripheral vessels under the nose decrease. Facial temperature changes by fear or joy in this study were the same as the previous studies which measured temperature of finger tip, when participants experiencing emotions. Our results may help to develop emotion-measuring techniques and establish computer system bases which are to detect human emotions.

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A study on the relationship between Schmidt Hammer's 'R' and bedrock microforms (기반암 하상 미지형과 슈미트 해머 반발 값과의 관계에 대한 연구)

  • KIM, Jong Yeon
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.3
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    • pp.51-69
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    • 2012
  • Physical strength of the rock is the most important factor of resistance to erosion and has been measured through various way. Bedrock microforms, like potholes and grooves, are the forms sculpted by the erosional processes of flow and the location and morphology are strongly affected by the differential erosion. It also assumed that the physical strength of the rock controls the erosion rate and mode of erosion. The schmidt hammer has been used to measure the rock strength in the field for the geomorphological research. To find the relationship between the rock strength and microforms, Schmidt hammer's R(rebound) were measured in the Baeksuktan, middle reach of Gilancheon, Cheongsong, Gyungsangbuk do. The overall values of rebound of the local sandstone showed over 65 in most cases, so it can be regarded as 'very strong'. It is found that the rebound values of the rock surface decreased towards current water level. It also, however, found that there was no systematic differences in rebound values among the topographically high and lows in the bedrock surface. There was no statistically significant difference in rebound values of the area with well developed microforms and others. The values of R from the exposed faces and inside of the microforms are similar. In the case of conglomerate, the part with the gravel showed higher values that the parts with sands. The rebound values are decreased near of(<1cm) the geological discontinuities(including joint and faults), so this line of weakness could be the point of initiation of active erosion to form microforms. However there is large variations in rebound values within this part. It also should be mentioned that topological relation between the strike of the geologic discontinuities and flow direction looks control the mode of erosional processes.

Numerical Analysis of Phase Behavior and Flow Properties in an Injection Tubing during Gas Phase CO2 Injection : Application of Demonstration-scale Offshore CO2 Storage Project in the Pohang Basin, Korea (기체상태의 CO2 주입시 주입관내 상변화 및 유동 특성의 수치해석적 연구 : 포항분지 해상 중소규모 CO2 지중저장 사업에 적용)

  • Jung, Woodong;Sung, Wonmo;Han, Jeong-Min;Song, Youngsoo;Wang, Jihoon
    • Journal of the Korean Institute of Gas
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    • v.25 no.4
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    • pp.10-18
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    • 2021
  • CO2 storage technology in an aquifer is one of the most effective way to decrease global warming due to a high storage capacity and economics. A demonstration-scale offshore CO2 storage project was performed in a geological deep aquifer in the Pohang Basin, Korea for a technological development of large-scale CO2 storage. A challenging issue in the early design stage of the project was to establish the proper injectivity during CO2 injection. To solve this issue, injection conditions were calculated by calculating injection rate, pressure, temperature, CO2 phase change, and thermodynamic properties. For this study, we simulated and numerically analyzed CO2 phase change from gas to supercritical phase and flow behavior in transport piping and injection tubing using OLGA program. Our results provide the injectivity conditions of CO2 injection system combined with a bottomhole pressure of an aquifer.

Comparative Investigation of Convective Heat Transfer Coefficients for Analyzing Compressed Hydrogen Fueling Process (압축 수소 충전 공정 해석을 위한 대류 열전달 계수 비교 분석)

  • Hyo Min Seo;Byung Heung Park
    • Journal of the Korean Institute of Gas
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    • v.27 no.3
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    • pp.123-133
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    • 2023
  • Commercial hydrogen fuel cell vehicles are charged by compressing gaseous hydrogen to high pressure and storing it in a storage tank in the vehicle. This process causes the temperature of the gas to rise, to ensure the safety to storage tanks, the temperature is limited. Therefore, a heat transfer model is needed to explain this temperature rise. The heat transfer model includes the convective heat transfer phenomenon, and accurate estimation is required. In this study, the convective heat transfer coefficient in the hydrogen fueling process was calculated and compared using various correlation equations considering physical phenomena. The hydrogen fueling process was classified into the fueling line from the dispenser to the tank inlet and the storage tank in the vehicle, and the convective heat transfer coefficients were estimated according to process parameters such as mass flow rate, diameter, temperature and pressure. As a result, in the case of the inside of the filling line, the convective heat transfer coefficient was about 1000 times larger than that of the inside of the storage tank, and in the case of the outside of the filling line, the convective heat transfer coefficient was about 3 times larger than that of the outside of the storage tank. Finally, as a result of a comprehensive analysis of convective heat transfer coefficients in each process, it was found that outside the storage tank was lowest in the entire hydrogen fueling process, thus dominated the heat transfer phenomenon.

Optimizing analytical method in Health Functional Food code with adjustable chromatographic parameters: A case study of vitamin C (건강기능식품공전 시험법의 크로마토그래프법 조건의 조정 및 비타민C에 대한 적용성 평가 연구)

  • Junghoon Shin;Yooseong Jeong;Yong Seok Choi;Sang Beom Han;Dong-Kyu Lee
    • Analytical Science and Technology
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    • v.37 no.3
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    • pp.143-154
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    • 2024
  • In this study, we improved the vitamin C test method and reviewed data on the adjustable range of chromatography conditions for quantification. First, we adjusted the mobile phase conditions such as solvent composition, salt concentration, pH and column temperature and in particular, it was confirmed through an improved test method that the peak derived from the buffer solution could be clearly separated from the target component, vitamin C by adjusting the pH. The retention time of vitamin C was partially changed by adjusting the column diameter, length and particle size but the number of theoretical plates indicated similar values and did not affect the separation and quantitative analysis of the target component. The flow rate according to the column specifications was derived from the equation proposed by the U.S. FDA (Food and Drug administration) and the Korean MFDS (Ministry of Food and Drug Safety), and evaluation of the applicability to vitamin complexes showed high selectivity for vitamin C even with altered stationary phase conditions and flow rates. In conclusion, vitamin C can be optimally separated and detected by changing the chromatographic method conditions and it was confirmed that the mobile and stationary phase conditions of liquid chromatography can be slightly adjusted in case the assay method uses an isocratic elution.

A study on the condition assessment of large diameter water valves using non-destructive technologies (비파괴 기술을 이용한 대구경 수도용 밸브의 상태평가에 관한 연구)

  • Ho-Min Lee;Hyun-yong Choi;Suwan Park;Tae-min Oh;Chae-Min Kim;Cheol-Ho Bae
    • Journal of Korean Society of Water and Wastewater
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    • v.37 no.4
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    • pp.215-229
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    • 2023
  • In this study, non-destructive technologies that can be applied to evaluate the integrity of valve materials, safety against internal pressure caused by corrosion, and the blocking function of large-diameter water valves during operation without requiring specimen collection or manpower entering the inside of the valve were tested to assess the reliability of the technologies and their suitability for field application. The results showed that the condition of the graphite structure inside the valve body can be evaluated directly through the optical microscope in the field without specimen collection for large-diameter water butterfly valves, and the depth of corrosion inside the valve body can be determined by array ultrasound and the tensile strength can be measured by instrumented indentation test. The reliability of each of these non-destructive techniques is high, and they can be widely used to evaluate the condition of steel or cast iron pipes that are significantly smaller in thickness than valves. Evaluation of blocking function of the valves with mixed gas showed that it can be detected even when a very low flow rate of mixed gas passes through the disk along with the water flow. Finally, as a result of evaluating the field applicability of non-destructive technologies for three old butterfly valves installed in the US industrial water pipeline, it was found that it is possible to check the material and determine the suitability of large-diameter water valves without taking samples, and to determine the corrosion state and mechanical strength. In addition, it was possible to evaluate safety through the measurement results, and it is judged that the evaluation of the blocking function using mixed gas will help strengthen preventive response in the event of an accident.

Runoff Analysis for Weak Rainfall Event in Urban Area Using High-ResolutionSatellite Imagery (고해상도 위성영상을 이용한 도시유역의 소강우 유출해석)

  • Kim, Jin-Young;An, Kyoung-Jin
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.6
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    • pp.439-446
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    • 2011
  • In this research, enhanced land-cover classification methods using high-resolution satellite image (HRSI) and GIS in terms of practicality and accuracy was proposed. It aims for understanding non-point pollutant origin/loading, assessment the efficiency of rainfall storage/infiltration facilities and sounds water-environment management. The result of applying enhanced land-cover classification methods to the urban region verifies that roof and road area are including various vegetations such as roof garden, flower bed in the median strip and street tree. This accounts for 3% of total study area, and more importantly it was counted as impervious area by GIS alone or conventional indoor work. The feasibility of the method was assessed by applying to rainfall-runoff analysis for three weak rainfall in the range of 7.1-10.5 mm events in 2000, Chiba, Japan. A good agreement between simulated and observed runoff hydrograph was obtained. In comparison, the hydrograph simulated with land-use parameters by the detailed land-use information of 10m grid had an error between 31%~71%, while enhanced method showed 4% to 29%, and showed the improvement particularly for reproducing observed peak and recession flow rate of hydrograph in weak rainfall condition.

A Study on the Liquid-Liquid Extraction by Use of Hydrophobic Hollow Fiber Module (소수성 중공사 모듈에 의한 액-액 추출에 관한 연구)

  • Kim, Young-II;Park, Dong-Won
    • Applied Chemistry for Engineering
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    • v.7 no.2
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    • pp.237-244
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    • 1996
  • Liquid-liquid extractions by use of microporous hollow fiber modules are fast compared with conventional extraction equipment because of the large surface area per volume. In these modules, the extractant and feed can be contacted at high speed and two flows are completely independent, so there are no problems with loading and channeling. In this paper, it was investigated the extraction selectivities for liquid-liquid extraction of Fe(II) and Ni(II) from dilute aqueous solution into TOA (tri-n-octylamine) and EHPNA (bis(2-ethylhexyle)hydrogenphosphite) as organic extractants by using the hydrophobic hollow fiber module. To determine the rate controlling step for mass transfer in hollow fibers, we also examined the effect of inside and outside flow rates of the hollow fiber module. From these experiments, we identified for the extraction of system with high partition coefficient in hydrophobic hollow fibers, mass transfer in the inside aqueous feed dominated the overall mass transfer, and in this paper, correlation between $K_w$ and $v_t$ was obtained as $K_w{\frac{d}{D}}=6.22\(\frac{d^2v_t}{LD}\)^{1/3}$ On the other hand, for the system with low partition coefficient, the resistance in the inside of hollow fibers was much less than membrane resistance because the extraction was not simple in the micropore. Thus, for systems with high partition coefficients, hydrophobic hollow fibers would be a better choice.

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Chromaticity(b*), Sheet Resistance and Transmittance of SiO2-ITO Thin Films Deposited on PET Film by Using Roll-to-Roll Sputter System (롤투롤시스템을 이용하여 PET 필름위에 제조된 SiO2-ITO 박막의 색도(b*), 면저항과 투과도 연구)

  • Park, Mi-Young;Kang, Bo-Gab;Kim, Jung-Soo;Kim, Hye-Young;Kim, Hu-Sik;Lim, Woo-Taik;Choi, Sik-Young
    • Korean Journal of Materials Research
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    • v.21 no.5
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    • pp.255-262
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    • 2011
  • This paper has relatively high technical standard and experimental skill. The fabrication of TCO film with high transparency, low resistance and low chromaticity require exact control of several competing factors. This paper has resolved these problems reasonably well, thus recommended for publication. Indium tin oxide(ITO) thin films were by D.C. magnetron roll-to-roll sputter system utilizing ITO and $SiO_2$ targets of ITO and $SiO_2$. In this experiment, the effect of D.C. power, winding speed, and oxygen flow rate on electrical and optical properties of ITO thin films were investigated from the view point of sheet resistance, transmittance, and chromaticity($b^*$). The deposition of $SiO_2$ was performed with RF power of 400W, Ar gas of 50 sccm and the deposition of ITO, DC power of 600W, Ar gas of 50 sccm, $O^2$ gas of 0.2 sccm, and winding speed of 0.56m/min. High quality ITO thin films without $SiO_2$ layer had chromaticity of 2.87, sheet resistivity of 400 ohm/square, and transmittance of 88% and $SiO_2$-doped ITO Thin film with chromaticity of 2.01, sheet resistivity of 709 ohm/square, and transmittance of more than 90% were obtained. As a result, $SiO_2$ was coated on PET before deposition of ITO, their chromaticity($b^*$) and transmittance were better than previous results of ITO films. These results show that coating of $SiO_2$ induced arising chromaticity($b^*$) and transmittance. If the thickness of $SiO_2$ is controlled, sheet resistance value of ITO film will be expected to be better for touch screen. A four point probe and spectrophotometer are used to investigate the properties of ITO thin films.

Experimental Study of Co-firing and Emission Characteristics Fueled by Sewage Sludge and Wood Pellet in Bubbling Fluidized Bed (기포 유동층 반응기를 이용한 하수슬러지 및 우드펠렛 혼소에 관한 연소 특성 분석 및 비교)

  • Lee, Youngjae;Kim, Jongmin;Kim, Donghee;Lee, Yongwoon
    • Clean Technology
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    • v.23 no.1
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    • pp.80-89
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    • 2017
  • The bubbling fluidized bed (BFB) reactor with a diameter of 0.1 m and a height of 1.2 m was used for experimental study of co-firing and emission characteristics fueled by sewage sludge (SS) and wood pellet (WP). The facility consists of a fluidized bed reactor, feeding system, cyclone, condenser and gas analyzer, The mean particle diameter and minimum fluidization velocity are $460{\mu}m$ and $0.21ms^{-1}$ respectively. SS produced from Korea and WP from Canada were examined. The various mixing ratios of WP were 20, 50, and 80% based on HHV. The equivalence ratio of 1.65, reactor temperature of $800^{\circ}C$, air flow rate of $100Lmin^{-1}$, and fluidization number of 4 were fixed in the BFB experiment. In TGA, the range of combustion temperature of SS was wider than that of WP. It represents that the combustibility of WP is higher than that of SS. The BFB reactor temperature was maintained between 800 and $900^{\circ}C$. CO emission of SS was high because of lower combustibility. $NO_X$ and $SO_X$ formation of SS were higher than that of WP since high nitrogen and sulfur contents of SS. CO, $NO_X$, and $SO_X$ formation were suppressed as the mixing ratio of WP was increased. The slagging and fouling tendencies show high in all test conditions.