• Title/Summary/Keyword: Bleeding Ratio

Search Result 300, Processing Time 0.033 seconds

Engineering Properties of Bleeding Reduction of Concrete Using AE Water Reducing Agent for the Type of Bleeding Reduction (블리딩저감형 AE감수제를 사용한 콘크리트의 공학적 특성)

  • Han, Cheon-Goo;Hwang, Yin-Seong;Lee, Seung-Hoon;Kim, Gyu-Dong
    • Journal of the Korea Institute of Building Construction
    • /
    • v.4 no.1
    • /
    • pp.133-140
    • /
    • 2004
  • This study is intended to investigate the properties of bleeding reduction of concrete using AE water reducing agent for the type of bleeding reduction with the replacement admixture. According to the results, when the adding ratio of AE water reducing agent for the type of bleeding reduction increases, a range of normal fluidity and aimed air content are satisfied, setting time is faster than that of normal AE water reducing agent. And bleeding amount decreases, bleeding speed is highest between 60 and 90 min, and sinking depth increases drastically in 50 min. When AE oater reducing agent for the type of bleeding reduction is added, compressive strength shows a slight variation by air content, but there is not a large influence by addition of AE water reducing agent for the type of bleeding reduction. Synthetically, it proves that AE water reducing agent for the type of bleeding reduction satisfies aimed air content in the range of normal slump and can reduce only bleeding without quality variation of compressive strength.

Development and Analysing the Practical Use of Bleeding Reduction Agent for Concrete (콘크리트용 블리딩저감제의 개발 및 실용성 검토)

  • Han, Cheon-Goo;Hwang, Yin-Seong;Shin, Dong-In
    • Journal of the Korea Concrete Institute
    • /
    • v.15 no.2
    • /
    • pp.217-224
    • /
    • 2003
  • It is necessary to reduce bleeding, which is a kind of segregation of fresh concrete, for improvement of quality of concrete structure. But, besides using high qualify material and adjusting mixture ratio, there is no easy solution to reduce bleeding by now. For that reason, this study is intended to develop bleeding reduction agent and to investigate its application. The test results are following. At first, recommended mixture ratio of bleeding reduction agent is proven to be MC viscosity agent : defoaming agent : superplasticyzer of 1 : 0.004 : 0.2. It goes to prove that bleeding reduction agent does not have bad effect on the quality of concrete such as fluidity, air content and the strength of hardened concrete etc, and can reduce bleeding effectively. Therefore it is thought that bleeding reduction agent can be applied to construction field effectively.

Balloon-Occluded Retrograde Transvenous Obliteration versus Transjugular Intrahepatic Portosystemic Shunt for the Management of Gastric Variceal Bleeding

  • Gimm, Geunwu;Chang, Young;Kim, Hyo-Cheol;Shin, Aesun;Cho, Eun Ju;Lee, Jeong-Hoon;Yu, Su Jong;Yoon, Jung-Hwan;Kim, Yoon Jun
    • Gut and Liver
    • /
    • v.12 no.6
    • /
    • pp.704-713
    • /
    • 2018
  • Background/Aims: Gastric varices (GVs) are a major cause of upper gastrointestinal bleeding in patients with liver cirrhosis. The current treatments of choice are balloon-occluded retrograde transvenous obliteration (BRTO) and the placement of a transjugular intrahepatic portosystemic shunt (TIPS). We aimed to compare the efficacy and outcomes of these two methods for the management of GV bleeding. Methods: This retrospective study included consecutive patients who received BRTO (n=157) or TIPS (n=19) to control GV bleeding from January 2005 to December 2014 at a single tertiary hospital in Korea. The overall survival (OS), immediate bleeding control rate, rebleeding rate and complication rate were compared between patients in the BRTO and TIPS groups. Results: Patients in the BRTO group showed higher immediate bleeding control rates (p=0.059, odds ratio [OR]=4.72) and lower cumulative rebleeding rates (logrank p=0.060) than those in the TIPS group, although the difference failed to reach statistical significance. There were no significant differences in the rates of complications, including pleural effusion, aggravation of esophageal varices, portal hypertensive gastropathy, and portosystemic encephalopathy, although the rate of the progression of ascites was significantly higher in the BRTO group (p=0.02, OR=7.93). After adjusting for several confounding factors using a multivariate Cox analysis, the BRTO group had a significantly longer OS (adjusted hazard ratio [aHR]=0.44, p=0.01) and a longer rebleeding-free survival (aHR=0.34, p=0.001) than the TIPS group. Conclusions: BRTO provides better bleeding control, rebleeding-free survival, and OS than TIPS for patients with GV bleeding.

Mach 6 Tests of Scramjet Engine with Boundary-Layer Bleeding and Two-Staged Injection

  • Kodera, Masatoshi;Tomioka, Sadatake;Kobayashi, Kan;Kanda, Takeshi;Mitani, Tohru
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2004.03a
    • /
    • pp.26-33
    • /
    • 2004
  • In this study, a boundary-layer bleeding and a two-staged fuel injection were applied to a scramjet engine for suppressing unstart transition and improving the thrust performance under Mach 6 flight conditions. With the boundary-layer bleeding, the engine could operate without unstart transition around at the fuel equivalence ratio of unity ($\Phi$ = 1). The thrust increment from the no fuel condition (dF) increased to 2460 N, which was about 1.4 times as large as that of the case without the bleeding and maximum in our Mach 6 tests. It was confirmed that the boundary-layer bleeding suppressed the separation during the engine operation. The two-staged fuel injection was less effective for improving the thrust performance com-pared with the single-staged one with the bleeding at Mach 6.

  • PDF

Effects of Hypovolemic Hypotension on Cardiopulmonary Functions and Acid-Base Balance (출혈성 쇼크가 심폐기능 및 산.염기평형에 미치는 영향)

  • Sou, Won-Young;Lee, Sung-Haing
    • Journal of Chest Surgery
    • /
    • v.6 no.2
    • /
    • pp.131-142
    • /
    • 1973
  • Studies of cardiopulmonary function and acid-base balance were performed on 29 dogs during control period, during oligemic hypotension and following return of blood to the animals. Intravenous morphine and local anesthesia were used. Fifteen of the 29 animals survived the complete experiment. The 14 animals that failed to survive the experimental period died between 15 to 90 minutes after the onset of bleeding. The results were as follows. 1. The heart rate increased after the onset of bleeding and failed to return to control level following reinfusion. Stroke volume decreased markedly after bleeding and failed to recover after return of blood from the reservoir. Cardiac output also decreased during oligemic hypotension and was maintained at this level after re-infusion. Total peripheral resistance decreased significantly immediately after bleeding, however it increased soon over the pre-bleeding level. Central venous pressure decreased after the onset of bleeding and remained at lower level for the rest of the experimental period. Arterial blood pressure, clown to 40-45 mmHg by acute hemorrhage, was elevated near to control level. Left ventricular work decreased tremendously during oligemic hypotension and failed to return to control level with the re-infusion of blood. Hematocrit value showed no significant decrease after bleeding and increased after re-infusion. Hemoglobin decreased after the onset of bleeding and recovered to control value after re-infusion. 2. The respiratory rate fell rapidly after bleeding from 124 to 29 and remained at this lower level for the remainder of the experiment. The tidal volume increased after bleeding and was maintained at this level for the remainder of the experiment. The respiratory minute volume showed no significant changes throughout the experimental period. Oxygen consumption fell lightly in all animals during oligemic hypotension and returned to normal levels following re-infusion. Arterial oxygen content and arterial oxygen saturation decreased following bleeding and the values returned to normal levels after the return of blood from the reservoir The arterio-venous oxygen difference increased after the onset of bleeding. It failed to return to normal values following re-infusion. Arterial $Pco_2$ decreased in all animals after the beginning of the bleeding. Partial pressure of $Co_2$ continued to fall until re-infusion, after which the values returned toward normal. Animals became acidotic. The pH fell to lower level following bleeding. Lactic acid and lactate: pyruvate ratio also increased during same period. Arterial pH and lactic acid failed to return to control value and lactate: pyruvate ratio increased more after re-infusion. Sodium bicarbonate decreased after bleeding and returned to control value following re-infusion.

  • PDF

Effects of Mineral Admixture on the Characteristics of Grout for PSC Bridge (광물질 혼화재가 PSC 교량용 그라우트의 특성에 미치는 영향)

  • Koh, Kyung-Taek;Ryu, Gum-Sung;Ahn, Ki-Hong;Kang, Su-Tae
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.2 no.1
    • /
    • pp.26-33
    • /
    • 2014
  • The study investigates the effects of the type, replacement ratio and method of use of mineral admixtures on the fluidity, bleeding ratio, volumetric change and compressive strength of the grout in order to provide basic data for the development of high-quality grout for PSC bridges. In view of the results relative to the type and replacement ratio of the mineral admixtures, it appears that fly ash has practically no effect on the improvement of the fluidity nor on the reduction of bleeding and shrinkage of the grout. On the contrary, blast furnace slag and silica fume appear to have significant effect on the improvement of the fluidity or on the reduction of bleeding and shrinkage of the grout. With regard to the combined use of mineral admixtures, the combination of fly ash and blast furnace slag provides satisfactory fluidity but with significant increase of bleeding and shrinkage, whereas the combination of blast furnace slag and silica fume reduces bleeding and shrinkage but with large loss of the fluidity. On the other hand, the combination of fly ash and silica fume results in satisfactory fluidity accompanied with fair reduction of bleeding and shrinkage of the grout. In view of these results, the type, replacement ratio and method of use of the mineral admixtures are seen to influence the fluidity, bleeding and volumetric change of the grout. Accordingly, it is necessary to select the mineral admixtures considering these effects for their exploitation in the grout of PSC bridges.

An Experimental Study on the Properties of Concrete using High Volume of Coal Ash

  • Kim, Moo Han;Choi, Se Jin
    • Architectural research
    • /
    • v.4 no.1
    • /
    • pp.39-44
    • /
    • 2002
  • Recently, the coal-ash production has been increased by increase of consumption of electric power. So it is important to secure a reclaimed land from pollution and develop practical application of coal ash. This is an experimental study to compare and analyze the properties of concrete using high volume of coal ash (including fly ash and bottom ash) as a part of fine aggregate. For this purpose, the mix proportions of concrete according to replacement ratio of coal ash (10, 20, 35, 50%) were selected. And then air content, slump, setting time, bleeding content, chloride content, compressive strength and carbonation test were performed. According to test results, it was found that the bleeding content of concrete using the coal ash decreased according to increase of replacement ratio. And the chloride content of concrete using the bottom ash as a part of fine aggregate increased as the replacement ratio of bottom ash increased, but it is satisfied with the total chloride content of concrete recommended by KCI - $0.3kg/m^3$ below. Also, the compressive strength of concrete using the bottom ash was similar to that of plain concrete(BA 0) after 28days of curing and the carbonation depth of concrete increased as the replacement ratio increased. However, the carbonation depth of concrete using the fly ash decreased as the replacement ratio of fly ash increased.

Mix Design of Polymer Grouting Mortar for Prepacked Concrete Using Polymer Dispersions (폴리머 디스퍼션을 이용한 프리팩트 콘크리트용 주입 모르타르의 배합에 관한 연구)

  • Jo, Young-Kug;Kim, Wan-Ki
    • Journal of the Korea Institute of Building Construction
    • /
    • v.8 no.5
    • /
    • pp.85-91
    • /
    • 2008
  • Prepacked concrete has recently been used in the special constructions fields such as underwater concrete work, heavy-weight concrete work, underground structure work, partial repair works for damaged reinforced concrete structures. and polymer-modified mortars have been employed as grouting mortars for the prepacked concrete. The purpose of this study is to recommend the optimum mix design of polymer-modified grouting mortars for prepacked concrete. Polymer-modified mortars using SBR and EVA emulsions as admixture of grouting mortars for prepacked concrete are prepared with various mix proportions such as sand-binder ratio, fly ash replacement ratio, polymer-binder ratio. and tested for flowability, viscosity of grouting mortars, bleeding ratio, expansion ratio, flexural and compressive strengths of grouting mortars and compressive and tensile strengths of prepacked concretes. From the test results, it is apparent that polymer-modified mortars can be produced as grouting mortars when proper mix design is chosen. We can design the mix proportions of high strength mortars for prepacked concrete according to the control of mix design factors such as type of polymer, polymer-binder ratio, sand-binder ratio and fly ash replacement ratio. Water-binder ratio of plain mortars for a constant flowability value are in the ranges of 43% to 50%. SBR-modified mortar has a little water-binder ratios compared to those of plain mortar, however, EVA-modified mortar needs a high water-binder ratio due to a high viscosity of polymer dispersion. The expansion and bleeding ratios of grouting mortars are also controlled in the proper value ranges. Polymer-modified grouting mortars have good flexural. compressive and tensile strengths, are not affected with various properties with increasing fly ash replacement to cement and binder-sand ratio. In this study, SBR-modified grouting mortar with a polymer-binder ratio of 10% or less, a fly ash replacement of 10% to cement and a sand-binder ratio of 1.5 is recommended as a grouting mortar for prepacked concrete.

Comparisons of Bleeding Risks between Rivaroxaban and Dalteparin for Treatment of Venous Thromboembolism in Cancer Patients (암환자의 정맥혈전색전증 치료에서 rivaroxaban과 dalteparin의 출혈 부작용 비교)

  • Kim, Yoon Kyung;An, Sook Hee;Kim, Jae Yeon;Chung, Jee Eun;Gwak, Hye Sun
    • Korean Journal of Clinical Pharmacy
    • /
    • v.26 no.3
    • /
    • pp.195-200
    • /
    • 2016
  • Background: Venous thromboembolism (VTE) is a common and life-threating condition in cancer patients. Low molecular weight heparins (LMWH), such as dalteparin, are recommended in the treatment of VTE. Also, rivaroxaban, an orally administered direct factor Xa inhibitor, was approved for the treatment of VTE. It showed similar efficacy to standard therapy (LMWH or warfarin) and was associated with significantly lower rates of major bleedings. However, in the real world, bleeding has been reported to occur frequently in cancer patient receiving rivaroxaban. The goal of this research was to analyze bleeding risks between rivaroxaban and dalteparin for treatment of VTE in cancer patients. Methods: Medical records of oncology patients who were treated with rivaroxaban or dalteparin for VTE from July 2012 to June 2014 were retrospectively reviewed. Data collected were as follows: age, sex, weight, height, cancer types and stages, ECOG (eastern cooperative oncology group) PS (performance score), VTE types, concurrently used medications, study drug information (dose and duration of therapy), INR (international normalized ratio), PT (prothrombin time), and platelet counts. Bleeding was classified into major bleedings, clinically relevant non-major bleedings, and minor bleedings. Results: A total of 399 patients were included in the study. Of these patients, 246 were treated with rivaroxaban and 153 with dalteparin. Bleeding rates were significantly higher in the rivaroxaban group than in the dalteparin group (adjusted odds ratio (AOR) 2.09, 95% CI 1.22-3.60) after adjusting for confounders. In addition, rivaroxaban remained independently associated with 1.78-fold (95% CI 1.14-2.76) shorter time to bleeding compared to dalteparin after adjusting other factors known to be associated with poor outcomes. Conclusion: This study suggested that rivaroxaban was associated with an increased risk of bleedings in cancer patients.

Printing Performance Evaluation of Water-dispersed Pigment Ink according to Additive Conditions of Film Substrate Surface Coating Agent (필름기재 표면 코팅제의 첨가물질 조성 조건에 따른 수분산 안료잉크의 프린팅 성능 평가)

  • Hyeok-Jin Kim;Hye-Ji Seo;Eun-Ha Kang;Min-Woo Han;Dong-Hyeon Lee;Dong-Jun Kwon;Jin-Pyo Hong
    • Textile Coloration and Finishing
    • /
    • v.35 no.4
    • /
    • pp.196-205
    • /
    • 2023
  • Water-dispersed pigment is on-going study for without air pollution in the textile and print industry. Primer treatment is essential for the substrate to improve the printing quality of eco-friendly water-dispersed pigment ink. Otherwise in the case of untreated primer, the water-dispersed pigment ink will dry onto the surface and cause defective images. This study was conducted on film substrate coating (primer) to fix eco-friendly water-dispersed pigment ink on film substrate. The drying, bleeding, and color strength of the pigment ink were examined depending on the composition and mixing ratio of the coating solution. The mixing ratio of silica gel in the coating film is increased to 0, 0.5, 1, 2 and 3 and results that DK-1-3 of silica gel ratio of 1 showed the lowest bleeding such as 52%, the letter thickness of 0.76mm and DK-1-5 of SG ratio of 3 showed the highest bleeding such as 304%, the letter thickness of 2.02mm. The mixing ratio of SPA in the coating film is increased to 2.5, 5, 7.5, SPA ratio of 7.5 has a bleeding ratio of 9% and letter thickness of 0.544mm. It showed the closest value to 0.5mm. According to the result, the optimal mixing ratio of binder, polymer coagulant, silica gel is 100:7.5:1.