• Title/Summary/Keyword: effective gravity

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Effect of dual-type oligosaccharides on constipation in loperamide-treated rats

  • Han, Sung Hee;Hong, Ki Bae;Kim, Eun Young;Ahn, So Hyun;Suh, Hyung Joo
    • Nutrition Research and Practice
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    • v.10 no.6
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    • pp.583-589
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    • 2016
  • BACKDROUND/OBJECTIVE: Constipation is a condition that can result from intestinal deformation. Because humans have an upright posture, the effects of gravity can cause this shape deformation. Oligosaccharides are common prebiotics and their effects on bowel health are well known. However, studies of the physiological functionality of a product that contains both lactulose and galactooligosaccharides are insufficient. We investigated the constipation reduction effect of a dual-type oligosaccharide, Dual-Oligo, in loperamide-treated rats. MATERIALS/METHODS: Dual-Oligo consists of galactooligosaccharides (15.80%) and lactulose (51.67%). Animals were randomly divided into four groups, the normal group (normal), control group (control), low concentration of Dual-Oligo (LDO) group, and high concentration of Dual-Oligo (HDO) group. After 7 days of oral administration, fecal pellet amount, fecal weight, watercontent of fecal were measured. Blood chemistry, short-chain fatty acid (SCFA), gastrointestinal transit ratio and length and intestinal mucosa were analyzed. RESULTS: Dual-Oligo increased the fecal weight, and water content of feces in rats with loperamide-induced constipation. Gastrointestinal transit ratio and length and area of intestinal mucosa significantly increased after treatment with Dual-Oligoin loperamide-induced rats. A high concentration of Dual-Oligo tended to produce more acetic acid than that observed for the control group, and Dual-Oligo affected the production of total SCFA. Bifidobacteria concentration of cecal contents in the high-concentration oligosaccharide (HDO) and low-concentration oligosaccharide (LDO) groups was similar to the result of the normal group. CONCLUSIONS: These results showed that Dual-Oligo is a functional material that is derived from a natural food product and is effective in ameliorating constipation.

Application of SBR Process to Treat Pickling Wastewater including the High Nitrate and Ca+2 (고농도 질산성질소와 Ca+2을 함유한 산세폐수의 효과적인 처리를 위한 SBR 공정의 적용)

  • Kim, Seung-jun;Choi, Yong-su;Bae, Woo-keun
    • Journal of Korean Society on Water Environment
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    • v.22 no.2
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    • pp.215-221
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    • 2006
  • This research presents results from laboratory and pilot-scale experiments to remove high-nitrate in pickling wastewater using the sequencing batch reactor (SBR) as a biological method. During the experimental periods, the influent concentrations of NOx-N and $Ca^{+2}$ were analyzed to be 350-1,600 and 700-800 mg/L, respectively. In order to provide carbon source for denitrification, methanol has been added in proportion to the influent nitrate loading. The mean concentrations of MLSS and MLVSS, the fraction of volatile solids in sludge and the sludge volume index were measured to be 27 g/L, 5 g/L, 18.5% and 7.5, respectively. The solid retention time was kept in the range of 18 to 22 days, specific denitrification rate ($U_{dn}$) was $0.301g{NO_3}^--N/gVSS/day$. The oxidized nitrogen concentration of effluent ranged 2-34 mg/L with an average of 5.2 mg/L, the overall reduction in total nitrogen was more than 99.2%. In order to treat the pickling wastewater including the high concentration of nitrate and $Ca^{+2}$, the continuous flow process is not suitable because the specific gravity of the sludge is considerably increased by $Ca^{+2}$, thus the SBR process is shown to be very effective to treat the pickling wastewater.

The Study on the Engineering Characteristics by Self-Hardening of Coal Ash (석탄회의 자경성에 따른 공학적 특성연구)

  • Sang, Jung-Hyuk;Shin, Woong-Gi;Kim, Ji-Won;Chun, Byung-Sik
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09b
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    • pp.81-87
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    • 2010
  • As enormous construction projects of land development are carried out around Korea, useful construction materials are needed to perform the construction projects. However, there are no more enough of fill and reclamation materials in our country. That is why the coal ash is expected to be utilized as an alternative material. Since the coal ash has the characteristics of a pozzolan and a selfhardening material, it is adjudged that coal ash has a great possibility to be used as a fill and reclamation material. In this study, grain size analysis, Atterberg limit test, and specific gravity test were performed to examine the physical characteristics of the coal ash about a self-hardening material before utilizing the coal ash in the construction. Compaction test, unconfined compression test were conducted to investigate the engineering characteristics according to mixture ratios of fly ash and bottom ash. As a result of the tests, it was confirmed that the mixing ratio 1:1 of fly ash and bottom ash is the most effective to use as a fill and reclamation material. If the mixture of coal ash is used as a backfill material with light weight around structure, it is expected to play a significant role in reducing earth pressure on the back of the structure. As described above, the coal ash should be considered as an alternative material of fill and reclamation materials since the result of the tests indicates that the coal ash is suitable to a useful material on the construction design.

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Chest Tube Drainage of the Pleural Space: A Concise Review for Pulmonologists

  • Porcel, Jose M.
    • Tuberculosis and Respiratory Diseases
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    • v.81 no.2
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    • pp.106-115
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    • 2018
  • Chest tube insertion is a common procedure usually done for the purpose of draining accumulated air or fluid in the pleural cavity. Small-bore chest tubes (${\leq}14F$) are generally recommended as the first-line therapy for spontaneous pneumothorax in non-ventilated patients and pleural effusions in general, with the possible exception of hemothoraces and malignant effusions (for which an immediate pleurodesis is planned). Large-bore chest drains may be useful for very large air leaks, as well as post-ineffective trial with small-bore drains. Chest tube insertion should be guided by imaging, either bedside ultrasonography or, less commonly, computed tomography. The so-called trocar technique must be avoided. Instead, blunt dissection (for tubes >24F) or the Seldinger technique should be used. All chest tubes are connected to a drainage system device: flutter valve, underwater seal, electronic systems or, for indwelling pleural catheters (IPC), vacuum bottles. The classic, three-bottle drainage system requires either (external) wall suction or gravity ("water seal") drainage (the former not being routinely recommended unless the latter is not effective). The optimal timing for tube removal is still a matter of controversy; however, the use of digital drainage systems facilitates informed and prudent decision-making in that area. A drain-clamping test before tube withdrawal is generally not advocated. Pain, drain blockage and accidental dislodgment are common complications of small-bore drains; the most dreaded complications include organ injury, hemothorax, infections, and re-expansion pulmonary edema. IPC represent a first-line palliative therapy of malignant pleural effusions in many centers. The optimal frequency of drainage, for IPC, has not been formally agreed upon or otherwise officially established.

Development and evaluation of punching shear database for flat slab-column connections without shear reinforcement

  • Derogar, Shahram;Ince, Ceren;Mandal, Parthasarathi
    • Structural Engineering and Mechanics
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    • v.66 no.2
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    • pp.203-215
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    • 2018
  • A large body of experiments have been conducted to date to evaluate the punching shear strength of flat slab-column connections, but it is noted that only a few of them have been considered for the development of the ACI Code provisions. The limited test results used for the development of the code provisions fall short of predicting accurately the punching shear strength of such connections. In an effort to address this shortfall and to gain an insight into the factors that control the punching shear strength of flat slab-column connections, we report a qualified database of 650 punching shear test results in this article. All slabs examined in this database were tested under gravity loading and do not contain shear reinforcement. In order to justify including any test result for evaluation punching shear database, we have developed an approved set of criteria. Carefully established set of criteria represent the actual characteristics of structures that include minimum compressive strength, effective depths of slab, flexural and compression reinforcement ratio and column size. The key parameters that significantly affect the punching shear strength of flat slab-column connections are then examined using ACI 318-14 expression. The results reported here have paramount significance on the range of applicability of the ACI Code provision and seem to indicate that the ACI provisions do not sufficiently capture many trends identified through regression of the principal parameters, and fall on the unsafe side for the prediction of the punching shear strength of flat slab-column connections.

Experimental Study on the Hydrophilic Porous Film Coating for Evaporative Cooling Enhancement

  • Lee, Dae-Young;Lee, Jae-Wan;Kang, Byung-Ha
    • International Journal of Air-Conditioning and Refrigeration
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    • v.13 no.2
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    • pp.99-106
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    • 2005
  • Falling film heat transfer has been widely used in many applications in which heat and mass transfer occur simultaneously, such as evaporative coolers, cooling towers, absorption chillers, etc. In such cases, it is desirable that the falling film spreads widely on the surface to form a thin liquid film to enlarge contact surface and to reduce the thermal resistance across the film and/or the flow resistance to the vapor stream over the film. In this respect, hydrophilic treatment of the surface has been tried to improve the surface wettability by decreasing the contact angle between the liquid and the surface. However, the hydrophilic treatment was found not very effective to increase the surface wettedness of inclined surfaces, since the liquid flow forms rivulet patterns instead of a thin film as it flows down the inclined surface and accelerates gradually by the gravity. In this work, a novel method is suggested to improve the surface wettedness enormously. In this work, the surface is treated to have a thin hydrophilic porous layer on the surface. With this treatment, the liquid can spread widely on the surface by the capillary force resulting from the porous structure. In addition to this, the liquid can be held within the porous structure to improve surface wettedness regardless of the surface inclination. The experiment on the evaporative cooling of inclined surfaces has been conducted to verify the effectiveness of the surface treatment. It is measured that the latent heat transfer increases almost by $80\%$ at the hydrophilic porous layer coated surface as compared with the untreated surface.

Triboelectrostatic Separation of Mixed Three Kinds of Plastics by a Two-stage Separation Process (2단계(段階) 분리공정(分離工程)에 의한 3종(種) 혼합(混合)플라스틱의 마찰하전(摩擦荷電) 정전선별(靜電選別))

  • Park, Chul-Hyun;Jeon, Ho-Seok;Baek, Sang-Ho;Park, Jai-Koo
    • Resources Recycling
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    • v.16 no.5
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    • pp.57-64
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    • 2007
  • Triboelectrostatic separation of mixed three kinds of plastics, PVC, PET and PMMA, in the range of similar gravity has been performed through a two-stage separation process. Polypropylene (PP) and high-impact polystyrene (HIPS) were found to be the most effective materials for a tribo-charger in the separation of PVC, PET and PMMA. In the 1st stage using the PP cyclone charger, PVC grade and recovery depended considerably on the air velocity (10 m/s), the relative humidity (<30%), the electric field (>200 kV/m) and the splitter position (+2 cm from the center) in the triboelelctrostatic separator unit. At an optimum condition a PVC grade of 99.6% and a recovery of 97.5% was achieved. In the 2nd stage using the HIPS cyclone charger, a PMMA grade of 98.3% and a recovery of 97.0% was obtained under the conditions of 10m/s air velocity, over 250 kV/m electric field, central splitter position and less than 40% relative humidity.

Recovery of PET from Final Plastic Wastes using HDPE Cyclone Charger (HDPE 싸이클론 하전장치(荷電裝置)를 이용한 종말품(終末品) 폐(廢)플라스틱으로부터 PET의 회수(回收))

  • Jeon, Ho-Seok;Park, Chul-Hyun;Baek, Sang-Ho;Kim, Byoung-Gon
    • Resources Recycling
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    • v.16 no.5
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    • pp.51-56
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    • 2007
  • Plastics are widely used in everyday life as very useful material. In Korea, about 4 million tons of plastic wastes are generated annually. However, recycling ratio is below 30%, and most of plastic wastes are disposed by landfill and incineration. Hence, the development of material separation technique that can recycle plastic wastes is a necessary situation. In this study, Triboelectrostatic separation for recovery of PET from final plastic wastes obtained from the sink product after wet-type gravity separation has been carried out. In the charging properties, the charge polarity and charge density of PET and PVC were very effective with the tirbo-charger made of PP and HDPE with the decrease in relative humidity. In material separation using HDPE cyclone charger, a PET grade of 96.80% and a recovery of 85.0% were achieved at 30 kV and the splitter position -2cm from the center. In order to obtain PET grade of 98.5%, PET recovery should be sacrificed by 24% with moving the splitter from the center to -6cm position.

Observational Properties of GSC 2855-0585 in the Vicinity of the Eclipsing Binary V432 Per

  • Koo, Jae-Rim;Lee, Jae Woo;Kim, Seung-Lee;Lee, Chung-Uk;Lee, Byeong-Cheol
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.142.1-142.1
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    • 2012
  • During the photometric runs of the eclipsing binary V432 Per in 2006, we serendipitously discovered peculiar light variations of GSC 2855-0585 that imaged on the same target field. Its brightness decreased about 0.02 mag for about 0.15 days in all B, V, and R bands. The depth, duration, and box-shaped light curves are very similar to those of typical transiting exoplanets. We gathered the time-series data of GSC 2855-0585 from the SuperWASP public archive and detected the same light variations with a period of about 2.406 days. The period and transitlike features were confirmed by photometric follow-up observations at a predicted epoch in 2010 November. In order to estimate the mass of the companion that produced the light variations, we obtained 10 high-resolution spectra with different orbital phases in 2010 November and 2011 October-December. The radial velocities showed large variations of about 44 km/s. It indicates that the transitlike light variations do not originate from a transiting exoplanet, but from the single-lined spectroscopic eclipsing binary with a cool dwarf companion. Using the photometric and spectroscopic data, we estimated the physical parameters of the eclipsing binary GSC 2855-0585, such as orbital period, effective temperature, surface gravity, and mass.

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The Effects of Servitization Acceptance on Performance through Mediation of Service Process & ICT Competency (서비스화 수용활동이 서비스화 추진성과에 미치는 영향 : 서비스 프로세스 역량과 ICT 역량의 매개적 역할)

  • Yoon, Yong;Kim, Youn Sung
    • Journal of Information Technology Services
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    • v.15 no.4
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    • pp.111-123
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    • 2016
  • The purpose if this study was to find and investigate effective mediation factors influencing performance of servitization through servitization acceptance activities by means of empirical results. According to the previous researches, two main mediation factors which were related with servitization competencies such as ICT competency of servitization and competency of servitization process were distinguished from lots of competencies which are relying on servitization process. Using a 373 sample data investigated from CEOs, directors and managers of small and medium sized firms in Korea, the structured mediation model was proposed. The measurement for the each variable was accepted for this study when the respondents were revealed to understand the servitization concepts which explained especially company's business moving towards the service specific gravity from selling existing products. The measurement for the each variable reflected that respondents were participating in any sort of servitization type or had intension to be involved with any servitization categories. The mediation hypotheses were tested in the way of analytical measures with the result of strong reliability. According to analysis, two mediators showed positive mediation role and statistically adopted between servitization acceptance activities and servitization performance in the 99% significant level. We confirmed that ICT competency of servitization and competency of servitization process were in the role of positive mediation between servitization acceptance activities and performance of servitization. The total of indirect effects were 0.2546 to support each mediation hypotheses. Tested two mediators were not on the same level. The most affecting mediation element on servitization performance was appeared as competency of servitization process. With the result of this study, we expect that the small and medium sized companies might have servitization business strategies including proper service competencies and mediators through acceptance activities to obtain suitable performance. According to the analysis, Companies which consider product-servitization need to set strategies to reinforce above two competencies.