• Title/Summary/Keyword: 압력예측

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Influence of Green Tea Powder on the Physical Properties of the Bread Flour and Dough Rheology of White Pan Bread (녹차분말 첨가가 소맥분의 물리적 특성과 제빵적성에 미치는 영향)

  • 황성연;최원균;이현자
    • The Korean Journal of Food And Nutrition
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    • v.14 no.1
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    • pp.34-39
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    • 2001
  • The purpose of this study was to examine physical properties of the addition of green tea powder on bread flour and dough rheology of white pan bread. Three levels(0.1, 0.5 and 1.0% ) of each green tea powder with bread flour were tested for their effects in dough mixing using rapid disco analyzer, alveogram and farinogram. Addition of green tea powder tended to reduce initial pasting temperature and increase peak viscosity, break down and set back. L(extensibility) and G(swelling index) value in alveogram showed decrement with increasing green tea powder. These meant that the volume of white pan bread would show same tendency. The use of green tea powder increased consistency and water absorption of the bread flour but decreased development time, salability and degree of softening on farinogram. White pan bread with green tea powder had higher value of hardness and springness than without it. Sensory evaluation determined that the white pan bread with 0.5% green tea powder had the highest score.

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Characteristics of Membrane Permeability on the Separation of Solid in a Liquid Livestock Manure (축분액비의 고액분리에 있어서 분리막의 투과특성)

  • 황명구;차기철;이명규
    • Journal of Animal Environmental Science
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    • v.6 no.3
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    • pp.175-184
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    • 2000
  • A lab-scale MF membrane reactor was installed to investigate the membrane permeability, characteristics of membrane fouling at each conditions, and quality of permeate (liquid livestock manure) in the separation of solid-matters using membrane. Experiment was divided three filtration type such as follows; continuous filtration, gravity filtration, and intermittent filtration. As a result of experiment, flux 1 LMH was maintained for 7days, and trans-membrane pressure(TMP) was increased gradually under 10cmHg, but it was increased immediately after 10cmHg, respectively. However, the flux was increased, the Tmax was decreased exponential more and more. During the pure-flux test, most of the fouling of membrane was reversible. At the gravity filtration, permeate could be obtained as 1.75 LMH for 3.5days without any other electronic pressure. As an investigation of membrane surface, this study could be decided that the reason of fouling at the lower flux (Run 1 and 2) was attached matters in membrane surface, but at the higher flux (Run 4-6) was concentration polarization.

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Classifications of Ecological Districts for Estuarine Ecosystem Restoration; Examples of Goseong Bay Estuaries, South sea, Korea (하구 생태 복원을 위한 생태구역 구분; 남해 고성만 고성천 인근 하구의 예)

  • An, Soon-Mo;Lee, Sang-Yong;Choi, Jae-Ung
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.16 no.2
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    • pp.70-80
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    • 2011
  • Estuarine ecosystem responds sensitively to natural and anthropogenic perturbations. lt is necessary to identify the direction of the change when the perturbation occurs as well as to understand the structure and functioning of estuarine ecosystem for a proper management of the area. In this study, the estuarine habitats were classified into different ecological districts so as to the switch from one district to another district could be related to the environmental change due to the perturbations. Total 16 ecological districts was defined according to the presence of barrage, salinity and vegetation characteristics. The defined ecological districts were applied to small estuaries in Goseong bay, south sea of Korea (Baedun, Guman, Maam, Goseong) to distinguish different regions which might have characteristic bottom topography, inclinations of river bottom, sediment characteristics, salinity structure and area of vegetation. Total 7 out of 16 ecological district was identified in this region; NFB (natural, fresh, bare), NHB (natural, high salinity, bare), NLV (natural, low salinity, vegetated) in natural (without barrage) estuaries and CFB (closed, fresh, bare), CFV( closed, fresh vegetated), CLV (closed, low salinity, vegetated), CHB (closed, high salinity, bare) in closed (with barrage) estuary. A comparison of environmental factors and biota between CHB and CLV demonstrated the effect of barrage on estuarine ecosystem. The height and sediment characteristics of CHB and CLV were similar but the average salinity was lower in CLV than in CHB due to the barrage, which produced favorable condition for the Phragmites australis in CLV. Information regarding the ecological districts in various sizes and location could be useful for predicting the ecosystem change due to natural and anthropogenic perturbations and for preparing management actions.

A Descriptive Study Of School Children's Knowledge, Attitudes And Practices Regarding Smoking (중학생들의 흡연에 대한 지식, 태도, 그리고 행동에 관한 기술적 연구)

  • Park, In-Hyae
    • Research in Community and Public Health Nursing
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    • v.7 no.2
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    • pp.420-436
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    • 1996
  • The goal of this study is to explore different risk factors for smoking and look at the relationships between knowledge, attitudes, and behavioral intentions regarding smoking among schoolchildren, in order to reduce teenage smoking. To achieve this goal a self-administered questionaire regarding smoking was provided to schoolchildren in the 7th and 8th grades in one junior high school in Jerusalem. The schoolchildren were exposed to 10-12 hours of a smoking prevention intervention program. The questionaire focused primarily on the personal characteristics, social environment, knowledge, attitudes, practices, and behavioral intentions of the children. Crosstabs were performed on each variable to determine if significant associations exist among the different variables. The statistical computer, package, SPSS PC, was used to manipulate the data along with Chi-square test. The findings were as follows : About 11% of the children aged 12-14 have ever smoked or are smoking currently, and about 24.0% of those who ever smoked started smoking at the age of 10. Boys smoke more(p<.01), poorer students(by self-perception of school performance) smoke more, and those who had peers who were smokers were more likely to smoke(p<.05). The percentage of the children who reported that either father or mother smoked was about 30%, but no statistical association was found between parental smoking and children's smoking, although trends were noted in the expected direction, i.e. more smokers among children of smokers. Only 1.1% of the children intended to smoke in the future, and 98.0% of the children indicated that they can or they might be able to withstand social pressure. Seventy percent of the children demonstrated medium to high knowledge about smoking, Males, 8th graders, better students, and those without friends who smoke had higher social pressure showed more negative attitudes(p<.01). Those with non-smoking siblings showed more negative behavioral intentions regarding smoking(p<.01), and better students showed more negative behavioral intentions. Those who had higher knowledge scores showed more negative attitudes towards smoking, but not significantly so. Those who had very negative behavioral intentions showed highly significant negative attitudes towards smoking(p<.01).

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A Study on the Hydrocarbon Dew Point Prediction by the Compositions of the Fuel Gas Mixtures (연료용 혼합가스 조성에 따른 탄화수소 이슬점 예측)

  • Kim, Young-Gu;Choi, Seul-Gi;Ahn, Jung-Jin;Lee, Chang-Eon
    • Journal of the Korean Institute of Gas
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    • v.19 no.3
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    • pp.44-48
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    • 2015
  • The equations of hydrocarbon dew points(DT) of the fuel gas mixtures have been derived using the multiple regression analysis. In QSDR(Quantitative Structure Dew-point Relationship), the principal descriptors are CN(average carbon number) and BI(the ratio of the branched isomers). QSDRs studied by changing the pressures of the fuel gas mixtures in the range of 100 kPa ~ 500 kPa are as follows; $$DT(^{\circ}C)=-683.1+1224.98CN-898.01CN^2+308.58CN^3-49.56CN^4+3.02CN^5-12.42BI$$ (at 100 kPa, $$R_{adj}{^2}=0.99$$) (1) $$DT(^{\circ}C)=-745.2+1351.66CN-978.1CN^2+332.7CN^3-52.96CN^4+3.20CN^5-12.84BI$$ (at 200 kPa, $$R_{adj}{^2}=0.99$$) (2) $$DT(^{\circ}C)=-795.4+1457.1CN-1051.1CN^2+357.53CN^3-57.07CN^4+3.46CN^5-13.10BI$$ (at 300 kPa, $$R_{adj}{^2}=0.99$$) (3) $$DT(^{\circ}C)=-868.1+1608.4CN-1156.0CN^2+393.38CN^3-63.06CN^4+3.85CN^5-13.39BI$$ (at 500 kPa, $$R_{adj}{^2}=0.99$$) (4) As the average carbon numbers in the mixed fuel being reduced or the ratio of the branched isomers having a boiling point lower increase, The hydrocarbon dew point becomes lower, The differences between the hydrocarbon-dew points determined by the multiple regression and those calculated by the commercial program, VMGSim are negligible.

Process Design of Carbon Dioxide Storage in the Marine Geological Structure: II. Effect of Thermodynamic Equations of State on Compression and Transport Process (이산화탄소 해양지중저장 처리를 위한 공정 설계: II. 열역학 상태방정식이 압축 및 수송 공정에 미치는 영향 평가)

  • Huh, Cheol;Kang, Seong-Gil
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.11 no.4
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    • pp.191-198
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    • 2008
  • To design a reliable $CO_2$ marine geological storage system, it is necessary to perform numerical process simulation using thermodynamic equation of state. $CO_2$ capture process from the major point sources such as power plants, transport process from the capture sites to storage sites and storage process to inject $CO_2$ into the deep marine geological structure can be simulate with numerical modeling. The purpose of this paper is to compare and analyse the relevant equations of state including ideal, BWRS, PR, PRBM and SRK equation of state. We also studied the effect of thermodynamic equation of state in designing the compression and transport process. As a results of comparison of numerical calculations, all relevant equation of state excluding ideal equation of state showed similar compression behavior in pure $CO_2$. On the other hand, calculation results of BWRS, PR and PRBM showed totally different behavior in compression and transport process of captured $CO_2$ mixture from the oxy-fuel combustion coal-fired plants. It is recommended to use PR or PRBM in designing of compression and transport process of $CO_2$ mixture containing NO, Ar and $O_2$.

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A Hierarchical Grid Alignment Algorithm for Microarray Image Analysis (마이크로어레이 이미지 분석을 위한 계층적 그리드 정렬 알고리즘)

  • Chun Bong-Kyung;Jin Hee-Jeong;Lee Pyung-Jun;Cho Hwan-Gue
    • Journal of KIISE:Software and Applications
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    • v.33 no.2
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    • pp.143-153
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    • 2006
  • Microarray which enables us to obtain hundreds and thousands of expression of gene or genotype at once is an epoch-making technology in comparative analysis of genes. First of all, we have to measure the intensity of each gene in an microarray image from the experiment to gain the expression level of each gene. But it is difficult to analyze the microarray image in manual because it has a lot of genes. Meta-gridding method and various auto-gridding methods have been proposed for this, but thew still have some problems. For example, meta-gridding requires manual-work due to some variations in spite of experiment in same microarray, and auto-gridding nay not carried out fully or correctly when an image has a lot of noises or is lowly expressed. In this article, we propose Hierarchical Grid Alignment algorithm for new methodology combining meta-gridding method with auto-gridding method. In our methodology, we necd a meta-grid as an input, and then align it with the microarray image automatically. Experimental results show that the proposed method serves more robust and reliable gridding result than the previous methods. It is also possible for user to do more reliable batch analysis by using our algorithm.

A rock physics simulator and its application for $CO_2$ sequestration process ($CO_2$ 격리 처리를 위한 암석물리학 모의실헝장치와 그 응용)

  • Li, Ruiping;Dodds, Kevin;Siggins, A.F.;Urosevic, Milovan
    • Geophysics and Geophysical Exploration
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    • v.9 no.1
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    • pp.67-72
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    • 2006
  • Injection of $CO_2$ into underground saline formations, due to their large storage capacity, is probably the most promising approach for the reduction of $CO_2$ emissions into the atmosphere. $CO_2$ storage must be carefully planned and monitored to ensure that the $CO_2$ is safely retained in the formation for periods of at least thousands of years. Seismic methods, particularly for offshore reservoirs, are the primary tool for monitoring the injection process and distribution of $CO_2$ in the reservoir over time provided that reservoir properties are favourable. Seismic methods are equally essential for the characterisation of a potential trap, determining the reservoir properties, and estimating its capacity. Hence, an assessment of the change in seismic response to $CO_2$ storage needs to be carried out at a very early stage. This must be revisited at later stages, to assess potential changes in seismic response arising from changes in fluid properties or mineral composition that may arise from chemical interactions between the host rock and the $CO_2$. Thus, carefully structured modelling of the seismic response changes caused by injection of $CO_2$ into a reservoir over time helps in the design of a long-term monitoring program. For that purpose we have developed a Graphical User Interface (GUI) driven rock physics simulator, designed to model both short and long-term 4D seismic responses to injected $CO_2$. The application incorporates $CO_2$ phase changes, local pressure and temperature changes. chemical reactions and mineral precipitation. By incorporating anisotropic Gassmann equations into the simulator, the seismic response of faults and fractures reactivated by $CO_2$ can also be predicted. We show field examples (potential $CO_2$ sequestration sites offshore and onshore) where we have tested our rock physics simulator. 4D seismic responses are modelled to help design the monitoring program.

Weathering Sensitivity Characterization for Rock Slope, Considering Time Dependent Strength Changes (시간에 따른 강도변화를 고려한 암반사면의 풍화민감특성 분석)

  • Lee Jeong-Sang;Bae Seong-Ho;Yu Yeong-Il;Oh Joung-Bae;Lee Du-Hwa;Park Joon-Young
    • Tunnel and Underground Space
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    • v.16 no.2 s.61
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    • pp.109-134
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    • 2006
  • Rocks undergo weathering processes influenced by changing in pressure-temperature condition, atmosphere, underground water, and rainfall. The weathering processes change physical and chemical characteristics of the rocks. Once the rocks are weathered, the characteristics of them are changed and, because of the changing, several disadvantages such as rock slope failures and underground water spouts are can occur. Before we cut a large rock slope, therefore, we must analyze current weathering conditions of rocks and predict weathering processes in the future. Through the results of such analyses, we can judge reinforcement works. In order to comply with such requests, chemical weathering sensitivity analysis which was analyzed from chemical weathering velocities and other characteristics of rocks has been applied in several prior construction works in Korea. But, It is defective to use directly in engineering fields because it was developed for soils(not rocks), it has too mny factors must be considered and the relationships between the factors are not clear, and it is hard to explain the weathering processes in engineering time range. Besides above, because it has been used for isotropic rocks, this method is hard to apply to anisotropic rocks such as sedimentary rocks. Acceding to studies from morphologists (e.g. Oguchi et al., 1994; Sunamura, 1996; Norwick and Dexter, 2002), time dependent strength reduction influenced by weathering shows a negative exponential function form. Appling this relation, one can synthesize the factors which influence the weathering processes to the strength reduction, and get meaningful estimates in engineering viewpoint. We suggest this weathering sensitivity characterization method as a technique that can explain time dependent weathering sensitivity characteristics through strength changes and can directly applied the rock slope design.

Pressure Drop Predictions Using Multiple Regression Model in Pulse Jet Type Bag Filter Without Venturi (다중회귀모형을 이용한 벤츄리가 없는 충격기류식 여과집진장치 압력손실 예측)

  • Suh, Jeong-Min;Park, Jeong-Ho;Cho, Jae-Hwan;Jin, Kyung-Ho;Jung, Moon-Sub;Yi, Pyong-In;Hong, Sung-Chul;Sivakumar, S.;Choi, Kum-Chan
    • Journal of Environmental Science International
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    • v.23 no.12
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    • pp.2045-2056
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    • 2014
  • In this study, pressure drop was measured in the pulse jet bag filter without venturi on which 16 numbers of filter bags (Ø$140{\times}850{\ell}$) are installed according to operation condition(filtration velocity, inlet dust concentration, pulse pressure, and pulse interval) using coke dust from steel mill. The obtained 180 pressure drop test data were used to predict pressure drop with multiple regression model so that pressure drop data can be used for effective operation condition and as basic data for economical design. The prediction results showed that when filtration velocity was increased by 1%, pressure drop was increased by 2.2% which indicated that filtration velocity among operation condition was attributed on the pressure drop the most. Pressure was dropped by 1.53% when pulse pressure was increased by 1% which also confirmed that pulse pressure was the major factor affecting on the pressure drop next to filtration velocity. Meanwhile, pressure drops were found increased by 0.3% and 0.37%, respectively when inlet dust concentration and pulse interval were increased by 1% implying that the effects of inlet dust concentration and pulse interval were less as compared with those changes of filtration velocity and pulse pressure. Therefore, the larger effect on the pressure drop the pulse jet bag filter was found in the order of filtration velocity($V_f$), pulse pressure($P_p$), inlet dust concentration($C_i$), pulse interval($P_i$). Also, the prediction result of filtration velocity, inlet dust concentration, pulse pressure, and pulse interval which showed the largest effect on the pressure drop indicated that stable operation can be executed with filtration velocity less than 1.5 m/min and inlet dust concentration less than $4g/m^3$. However, it was regarded that pulse pressure and pulse interval need to be adjusted when inlet dust concentration is higher than $4g/m^3$. When filtration velocity and pulse pressure were examined, operation was possible regardless of changes in pulse pressure if filtration velocity was at 1.5 m/min. If filtration velocity was increased to 2 m/min. operation would be possible only when pulse pressure was set at higher than $5.8kgf/cm^2$. Also, the prediction result of pressure drop with filtration velocity and pulse interval showed that operation with pulse interval less than 50 sec. should be carried out under filtration velocity at 1.5 m/min. While, pulse interval should be set at lower than 11 sec. if filtration velocity was set at 2 m/min. Under the conditions of filtration velocity lower than 1 m/min and high pulse pressure higher than $7kgf/cm^2$, though pressure drop would be less, in this case, economic feasibility would be low due to increased in installation and operation cost since scale of dust collection equipment becomes larger and life of filtration bag becomes shortened due to high pulse pressure.