• Title/Summary/Keyword: Flow state

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An Experimental Study on the Heat Transfer Characteristics during Outward Melting Process of Ice in a Vertical Cylinder(comparison of thermal performance on the flow direction of working fluid) (수직원통형 빙축열조내 얼음의 외향용융과정시 전열특성에 관한 실험적 연구(작동 유체의 유입 방향에 따른 비교))

  • Kim, D.H.;Kim, D.C.;Kim, I.K.;Kim, Y.K.;Yim, C.S.
    • Solar Energy
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    • v.16 no.2
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    • pp.113-122
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    • 1996
  • This study presents experimental results of heat transfer characteristics of P.C.M. during outward melting process in a vertical cylinder. The experiment was carried out in six conditions, i. e., three different inlet temperature($7^{\circ}C,\;4^{\circ}C\;and\;1^{\circ}C$) and two directions of working fluid(upward and downward). Melting P.C.M. produced a bell-shaped phase change interface. When the inlet temperature was $7^{\circ}C$, the lower region remained at $4^{\circ}C$ until the temperature of upper region reached $4^{\circ}C$. This was due to the state of maximum density of the lower region. When the direction of the working fluid in the case of $7^{\circ}C$, inlet temperature, was upward, the rate of melting and the total melting energy were higher than when it's direction was downward. But the rate of melting and the total melting energy appeared higher value as it's direction was downward when the inlet temperature is $4^{\circ}C$ and $1^{\circ}C$.

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A Study on the Sequence Analysis Technique of Urban Landscape Color and Urban Color Characteristics in accordance with Spatial Openness - Focusing on the View of the Daegu Monorail - (도시 경관색채의 시퀀스 분석기법과 공간 개방도에 따른 도시색채 특성연구 - 대구광역시 지상철 조망을 중심으로 -)

  • Koo, Min-Ah
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.6
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    • pp.120-136
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    • 2016
  • This study, views the color of scenery not as a static state, but rather as a continuous sequence of perceptions that incorporates the concept of time. This study derived techniques to quantitatively analyze the flow and data from this sequence. By utilizing this, urban color trends can be based on openness. This is very close to what would be experienced by an actual viewer: it extracted color data and visual amount from frames at 2-second intervals by shooting a video of the color sequence of the city as seen from both the left and right sides from the inside of the monorail (line 3 of the Daegu urban railway). These images were classified by color group, brightness, chroma, high chroma distribution derived techniques such as openness of space, brightness level, clarity level, high-chroma distribution and code, advantage of visual amount, dominant factor exposure, hot and cold color image and dynamic of sequence rhythm. During the derived sequence, the data determines the openness in the visual amount of sky and it was found that the tendency of the colors of the city was opening regression analysis. The more colorful the city is opening the brightness is lowered, the chroma increased slightly, cold colors significantly increased, which also had a very deep relationship with Lynch enclosed proportion, color change of the city trends through the actual scenery could grasp in more detail.

Camphor Inhibits Adipocyte Differentiation via Its Impact on SMO-dependent Regulation of Hedgehog Signaling (Camphor의 Hedgehog 신호 SMO 조절을 통한 지방구세포 분화 억제효과)

  • Choi, Jae Young;Lim, Jong Seok;Lee, Ja Bok;Yang, Yung Hun
    • Journal of Life Science
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    • v.30 no.11
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    • pp.973-982
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    • 2020
  • In this study, we examined inhibition of adipocyte differentiation associated with the administration of camphor, a substance identified in extracts of the flowering plant Chrysanthemum indicum L. (CI). No camphor-mediated cytotoxicity was observed over a period of 1-10 days in studies targeting cells of the 3T3-L1 adipocyte-like line. Experiments that featured siRNA-mediated suppression of the transmembrane proteins Patched (PTCH) and Smoothened (SMO) resulted in inhibition and activation of differentiation, respectively. Interestingly, inhibition of PTCH typically activates SMO protein targeting and serves to activate hedgehog (HH)-mediated signaling. The results of our study suggest that activation of HH-mediated signaling can inhibit adipocyte differentiation. Furthermore, expression of glioma-associated oncogene homologue 1 (Gli1) was detected by flow cytometry in 62.7±1.5% of cells in response to administration of Lactobacillus rhamnosus (KCTC 3237) and in 60.4±2.2% of cells in response to camphor; these levels are higher than those detected in undifferentiated controls (24.9±3.1%). No change in the state of fermented camphor was identified by gas chromatography-mass spectrometry (GC-MS), but a 15.41% quantitative increase was confirmed in KCTC 3237. Overall, we conclude that administration of camphor resulted in overexpression of SMO and modulated the differential expression of Gli1. Animal studies focused on the impact of camphor as an agent to counteract obesity might be considered in the future. Indeed, camphor and similar physiologically active compounds from fermented CI might be developed as new and effective treatments for obesity.

Status of Development of Pyroprocessing Safeguards at KAERI (한국원자력연구원 파이로 안전조치 기술개발 현황)

  • Park, Se-Hwan;Ahn, Seong-Kyu;Chang, Hong Lae;Han, Bo Young;Kim, Bong Young;Kim, Dongseon;Kim, Ho-Dong;Lee, Chaehun;Oh, Jong-Myeong;Seo, Hee;Shin, Hee-Sung;Won, Byung-Hee;Ku, Jeong-Hoe
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.3
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    • pp.191-197
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    • 2017
  • The Korea Atomic Energy Research Institute (KAERI) has developed a safeguards technology for pyroprocessing based on the Safeguards-By-Design (SBD) concept. KAERI took part in a Member-State Support Program (MSSP) to establish a pyroprocessing safeguards approach. A Reference Engineering-scale Pyroprocessing Facility (REPF) concept was designed on which KAERI developed its safeguards system. Recently the REPF is being upgraded to the REPF+, a scaled-up facility. For assessment of the nuclear-material accountancy (NMA) system, KAERI has developed a simulation program named Pyroprocessing Material Flow and MUF Uncertainty Simulation (PYMUS). The PYMUS is currently being upgraded to include a Near-Real-Time Accountancy (NRTA) statistical analysis function. The Advanced Spent Fuel Conditioning Process Safeguards Neutron Counter (ASNC) has been updated as Non-Destructive Assay (NDA) equipment for input-material accountancy, and a Hybrid Induced-fission-based Pu-Accounting Instrument (HIPAI) has been developed for the NMA of uranium/transuranic (U/TRU) ingots. Currently, performance testing of Compton-suppressed Gamma-ray measurement, Laser-Induced Breakdown Spectroscopy (LIBS), and homogenization sampling are underway. These efforts will provide an essential basis for the realization of an advanced nuclear-fuel cycle in the ROK.

Spatial Variability of Hydraulic Properties in a Multi-Layered Soils of Japanese Larch (Larix leptolepis) Stand (낙엽송림분의 다층구조 토광에 있어서 수리특성의 공간 변리)

  • Chung Doug Young;Jin Hyun O
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.1 no.1
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    • pp.29-35
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    • 1999
  • Soil structure and organic matter have been known to strongly affect water flow and solute transport, yet little information is available concerning soil hydraulic properties related to soil physical and chemical properties in the forest site. The purpose of this study was to quantify the spatial variability and spatial correlation of the measured parameter values from the plots established with the rainfall simulator on Japanese larch(Larix leptolepis) dominated site in Kwangju. Kyunggi-Do. Measurement of soil water flux and retention were made with the inherent soil texture, soil structure, and organic matter. The method was based on the observation that when water was applied at a constant rate to the soil surface on each plot. The method was simple to apply and consists of following steps: (i) Wet the soil from a rainfall simulator with several known discharge rates on a relatively leveled soil surface with and without organic matter. (ii) Once the borders of the ponded zone were steady, saturated hydraulic conductivity( $K_{s}$) and the matric flux function(F) was evaluated from a regression of flux vs. the reciprocal of the ponded area. A conductivity of the form $K_{i+}$$_1$ $_{c}$= $K_{i}$( $_{c}$) [1-d /dz] where flux continuity implies. For this, continuity of matric potential at the interface at all times are as follows: $_1$( $Z_{c}$) = $_2$( $Z_{c}$) = $_{c}$ for steady state intake from water ponded on the soil surface. Results of this investigation showed the importance of understanding spatial variability in wide differences of water retention and saturated hydraulic conductivity with respect to pore geometry and organic matter contents which influenced the water flux throughout the soil profile.l profile.ile.

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How is Scientific and Technological Knowledge Linked in Technological Innovation in Korea? (우려나라 기술혁신에서의 과학-기술 지식연계 특성분석)

  • Park, Hyun-Woo;Son, Jong-Ku;You, Yeon-Woo
    • Journal of Korea Technology Innovation Society
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    • v.14 no.1
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    • pp.1-21
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    • 2011
  • Technical change and technological innovation have become major drivers of economic progress in the knowledge oriented economies where growth, productivity, and competitiveness are increasingly based on improved technologies, novel products, upgraded processes or customized services. The creation of new knowledge, modifying or improving existent knowledge, or imitation of others, has become central to economic development. New discoveries, state-of-the-art information gathering procedures, or successful problem solving routines are often at he core of these innovations. Despite the generally acknowledged importance of science in many high-tech areas of major economic relevance, there is few science-related statistics to be found in high-profile international benchmarking reports. This paper aims to provide an answer by advancing our understanding of the possibilities of indicators quantifying linkages between science and technology. Central are the concepts of innovation capability and science/technology interface, which are used to assemble a wide range of empirical studies and quantitative indicators to summarize their possibilities and limitations for producing comparative statistics. For the purpose of the study, we extracted the US patents by Korean assignees or inventors, scientific papers cited in the patents in order to analyze the characteristics of linkage of scientific knowledge flows. The review focuses on indicators dealing with flows of written or codified information, and indicators of inventiveness that capture the non-codifiable tacit knowledge dimension. General conclusions will be drawn with a view towards further developments in the foreseeable future, suggesting new avenues for the design and implementation of patent-based and inventor-based relationships between scientific research and technical development within the context of regional or national systems of innovation.

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Physicochemical Properties of a Biopolymer Flocculant Produced from Bacillus subtilis PUL-A (Bacillus subtilis PUL-A로부터 생산된 Biopolymer 응집제의 물리화학적 특성)

  • Ryu, Mi-Jin;Jang, Eun-Kyung;Lee, Sam-Pin
    • Microbiology and Biotechnology Letters
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    • v.35 no.3
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    • pp.203-209
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    • 2007
  • Soybean milk cake (SMC) was used for the solid-state fermentation by Bacillus subtilis PUL-A isolated from soybean milk cake. In the presence of 5% glutamate the maximum production of biopolymer (59.9 g/kg) was performed by fermentation at $42^{\circ}C$ for 24 hr. The recovered biopolymer was consisted of 87% $\gamma$-polyglutamic acid with molecular weight of $1.3{\times}10^6$ dalton and other biopolymer. The biopolymer solution showed the great decrease in consistency below pH 6.0, regardless of the molecular weight of PGA. Biopolymer solution has a typical pseudoplastic flow behavior and yield stress. The consistency of biopolymer solution was greatly decreased by increasing heating time and temperature in acidic condition compared to the alkaline condition. In kaolin clay suspension, the flocculating activity of biopolymer was the highest value with 15 mg/L biopolymer and 4.5 mM $CaCl_2$, but decreased greatly with $FeCl_3$. The flocculating activity of biopolymer was maximum at pH5, but decreased drastically by heating at $60{\sim}100^{\circ}C$. In particular, biopolymer with native PGA showed the efficient flocculating activity compared to that of modified biopolymer containing low molecular weight of PGA.

Review of Geography Books for Joseon Dynasty Urban Research - Focused on Donggukyeojiji, Yeojidoseo, Yeodobiji and Daedongjiji - (조선시대 도시연구를 위한 지리지(地理志)의 기초연구 - 『동국여지지(東國輿地志)』·『여지도서(輿地圖書)』·『여도비지(輿圖備志)』·『대동지지(大東地志)』를 중심으로 -)

  • Kang, Seo-Yeon;Yoon, In-Suk
    • Journal of architectural history
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    • v.21 no.5
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    • pp.33-46
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    • 2012
  • The purpose of this study lies on reinterpreting the geography books in Joseon dynasty as records of the cities and consequently suggesting directions for further urban research. Geography books of Joseon dynasty are valuable references to understand the national policy, and imply that the focus of the contents is on the system. Especially, military system is an important concept to understand city type in that period, relationships between cities, selection of location, etc. The results of review are as following: First, military system is not a permanent fixture and therefore reflects changes in urban policies along with the history. The system suggests valuable clues on urban development as it is state-run, and closely associated with national land development. Second, counties and prefectures under jurisdiction of district called Eupchi(邑治) had cities as important as or even more important than local government such as Yeong-a(營衙), Jinbo(鎭堡), Yeok(驛: administrative cities). Such special regions need to be studied as other type of cities in Joseon dynasty by defining their architectural characteristics and roles. Third, the relationship of cities such as Eupch, Yeong-a, and Jinbo, was reorganized according to the local military system. Eupchi, administrative city, along with Yeong-a and Jinbo evolved into a military city as it became systematically organized. The characteristics of Yeok needs to be reconsidered in the context of such new inter-city relationship. Fourth, considerations which should be reviewed in the geography based on this concept can be mainly classified into architecture and landscape. This will also lay the foundation, and suggest new directions for further research for Eupchi, Yeong-a, Jinbo, and Yeok. Fifth, description of the geography looks simple at first sight, but with thorough understating on the system, there are chances to interpret objective reasoning of position and landscape in the overall flow of region, area, etc. Bongsu(烽燧), signal-fire, can be an object of comparison with geographical features and position. Furthermore, advantageous position is a historical and geographical element showing the major context of the region.

Economic Design of Activated Sludge System at the Optimum Sludge Concentration (슬러지 농도 최적화에 따른 합리적인 활성슬러지공정 설계방안 연구)

  • Lee, Byung Joon;Choi, Yun Young
    • Journal of Korea Water Resources Association
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    • v.47 no.5
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    • pp.483-490
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    • 2014
  • The design procedures for a biological reactor and a secondary settling tank (SST) of an activated sludge system are based on the steady state design method (Ekama et al., 1986; WRC, 1984) and the 1-D flux theory design method (Ekama et al., 1997), respectively. This study combined both of the design procedures, to determine the optimum sludge concentration in the reactor and the best design with the lowest cost. The best design of the reactor volume and the SST diameter at the optimum sludge concentration were specified with varying wastewater and sludge characteristics, temperature, sludge retention time (SRT) and peak flow rate. The effects of the influent wastewater characteristics, such as substrate concentration and unbiodegradable particulate fraction, were found to be considerable, but the effect of unbiodegradable soluble fraction was to be negligible. The effects of sludge settling characteristics, were also significant. SRT, as an operating parameter, was found to be an important factor for determining the optimum sludge concentration. However, the effect of temperature was found to be small. Furthermore, for designing a large scale wastewater treatment plant, the number of reactors or SSTs could be estimated, by dividing the total reactor volume or SST area. The new combined design procedure, proposed in this research, will be able to allow engineers to provide the best design of an activated sludge system with the lowest cost.

A Comparison Study of MMP Inhibitors' and Doxorubicin's Effects on the Apoptosis of U2OS Osteosarcoma Cell Line (U2OS 골육종 세포주의 세포자멸사에서 MMP억제제와 Doxorubicin 작용의 비교연구)

  • Moon, Jeong-Seok;Yeom, Bum-Woo
    • The Journal of the Korean bone and joint tumor society
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    • v.13 no.2
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    • pp.88-95
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    • 2007
  • Purpose: The purpose of this study was to compare the proapoptotic effects of matrix metal-loproteinase inhibitor (MMPI) and doxorubicin on wild-type p53 osteosarcoma cell line, socalled U2OS cell line. Materials and Methods: U2OS cells were treated with MMP inhibitor III (MMPI III) and doxorubicin, either respectively or simultaneously. In cells treated with doxorubicin, Fas-neutralizing antibody so called ZB4 was additionally treated to examine whether the doxorubicin played a role through the Fas/FasL pathway. Cells were analysed regarding to apoptosis and cell death by flow cytometry. Results: U2OS cells incubated with doxorubicin showed significant amount of cell death in dose-dependent manner. However, those incubated with MMPI III mostly remained viable state. In addition, there is no relationship between two drugs. Cells treated with doxorubicin and ZB4 at the same time did not show down regulation of apoptosis through inhibition of Fas/FasL pathway. Conclusion: It is important to re-examine MMP inhibitor's effect on other osteosarcoma cell line with wild-type p14 as well as wild-type p53 to evaluate its proapoptotic effect.

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