Journal articles: 'Mixed Compression'

1

Goldkrand, John W. "Mixed cord compression." American Journal of Obstetrics and Gynecology 160, no. 1 (January 1989): 276. http://dx.doi.org/10.1016/0002-9378(89)90145-2.

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Mosti, G. "Compression therapy in mixed ulcers." JMV-Journal de Médecine Vasculaire 43, no. 4 (July 2018): 223–24. http://dx.doi.org/10.1016/j.jdmv.2018.06.004.

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Xing, Guoqi, Changjiang Liu, Wei Xuan, Yueyue Pan, Bing Zhang, and Yue Zhao. "Prediction of Unconfined Compression Strength for Saline-Alkaline Soils Mixed with Cement and Wheat Straw." Advances in Materials Science and Engineering 2020 (April 21, 2020): 1–14. http://dx.doi.org/10.1155/2020/2765145.

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A series of unconfined compression tests were performed to investigate the influence of wheat straws on the unconfined compression strength for saline-alkaline soils and saline-alkaline soils mixed with cement. In unconfined compression tests, 20 groups of soil specimens were prepared at five different percentages of wheat straws content (i.e., 0.0%, 0.1%, 0.15%, 0.2%, and 0.25% by weight of saline-alkaline soils) and four different percentages of cement content (i.e., 0%, 3%, 6%, and 9% by weight of saline-alkaline soils), and unconfined compression tests were carried out after 3-, 7-, 14-, 28-, and 56-day curing periods. Test results indicated that the inclusion of wheat straws within saline-alkaline soils and saline-alkaline soils mixed with cement leads to an increase in the unconfined compressive strength of specimens and also changed the brittle behavior to a more ductile one for specimens. In addition, based on the results from unconfined compression tests, a formula for predicting the unconfined compression strength of specimens related to cement content, wheat straw content, curing periods, etc., was determined, and comparing with the results from unconfined compression tests, it had higher precision in predicting the unconfined compression strength of specimens.

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Mosti, Giovanni. "Compression in mixed ulcers: venous side." Phlebology: The Journal of Venous Disease 29, no. 1_suppl (May 2014): 13–17. http://dx.doi.org/10.1177/0268355514526676.

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Introduction: arterial involvement may coexist in about 15–30 of venous ulcers. In this case compression therapy maybe applied, only by expert caregivers, with a reduced pressure which must not overcome the arterial pressure at ankle and foot level. It remains to assess if such a reduced pressure may be effective also on the impaired venous hemodynamics. Aim of this paper is to present an overview of the data we have, showing the effects on venous hemodynamics of a reduced compression pressure. Material and methods: in different groups of patients affected by deep and superficial venous incompetence, venous reflux and ejection fraction (EF) from the lower leg were measured in baseline conditions, without any compression, and after application of different elastic and inelastic compression devices exerting different pressure ranges from 20 to 60 mm Hg. The compression pressure was always recorded simultaneously with venous reflux of EF assessment. Results: strong pressures show the greatest effect in reducing/abolishing venous reflux and increasing EF but also a reduced pressure in the range of 20 to 40 mm Hg is effective in improving venous hemodynamics provided inelastic materials are used. Conclusions: inelastic but not elastic materials exert a standing pressure which is significantly higher than in supine position even starting from a reduced supine pressure of 40 mm Hg which does not impair the arterial inflow. This strong pressure is able to reduce and even abolish the venous reflux and improve the EF up to restoring its normal range. A reduced or modified compression pressure is able to significantly improve the venous hemodynamics without affecting the arterial inflow in patients with mixed ulcers, provided inelastic materials are used.

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Misra, R. S. "Energy-Exergy Performance Comparison of Vapour Compression Refrigeration Systems using Three Nano Materials Mixed in R718 in the Secondry Fluid and Ecofriendly Refrigerants in the Primary Circuit and Direct Mixing of nano Materials in the Refrigerants." International Journal of Advance Research and Innovation 3, no. 3 (2015): 45–53. http://dx.doi.org/10.51976/ijari.331507.

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This paper describes thermal modelling of vapour compression refrigeration system using (ii) eco-friendly refrigerants in primary circuit with nano particles mixed with R718 in secondary evaporator circuit. This model takes care of the secondary nanoparticles mixed in the fluids as input conditions as geometric characteristics of the system such as size of nanoparticles and the compressor speed to predict the secondary fluids output temperatures, the operating pressures, the compressor power consumption and the system overall energy performance. Such design analysis is conveniently useful to compare the thermal performance of different nanoparticles (Cu, Al2O3, TiO2) based nanofluid as a secondary fluid in a vapour compression refrigeration system. The influence of input variables on the irreversibilities in terms of exergy destruction ratio of the system is presented. Such a model can also be used to design various components viz. evaporator, compressor, condenser and throttle valve for vapour compression refrigeration systems for any desired cooling capacity. This model takes care of use of nanofluids as a secondary fluid in vapour compression refrigeration systems and simulate the non-linear equations of the system. It was observed that for the same geometric characteristics of the system, first and second law performance improved from 8% to 17% by using eco-friendly refrigerants in the primary circuit and nanoparticles mixed with water as a secondary fluid in VCS .and first and second law performance improved from 8% to 32% by mixing nano particles in the eco-friendly refrigerants in the primary circuit

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Yang, Chen, Ping Pan, and Qun Ding. "Image Encryption Scheme Based on Mixed Chaotic Bernoulli Measurement Matrix Block Compressive Sensing." Entropy 24, no. 2 (February 14, 2022): 273. http://dx.doi.org/10.3390/e24020273.

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Many image encryption schemes based on compressive sensing have poor reconstructed image quality when the compression ratio is low, as well as difficulty in hardware implementation. To address these problems, we propose an image encryption algorithm based on the mixed chaotic Bernoulli measurement matrix block compressive sensing. A new chaotic measurement matrix was designed using the Chebyshev map and logistic map; the image was compressed in blocks to obtain the measurement values. Still, using the Chebyshev map and logistic map to generate encrypted sequences, the measurement values were encrypted by no repetitive scrambling as well as a two-way diffusion algorithm based on GF(257) for the measurement value matrix. The security of the encryption system was further improved by generating the Secure Hash Algorithm-256 of the original image to calculate the initial values of the chaotic mappings for the encryption process. The scheme uses two one-dimensional maps and is easier to implement in hardware. Simulation and performance analysis showed that the proposed image compression–encryption scheme can improve the peak signal-to-noise ratio of the reconstructed image with a low compression ratio and has good encryption against various attacks.

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Liang, Wen Yan, Zhen Qing Wang, Bo Zhou, and Hong Qing Lv. "The Elastic-Viscoplastic Field at the Mixed-Mode Crack-Tip under Compression and Shear." Key Engineering Materials 385-387 (July 2008): 321–24. http://dx.doi.org/10.4028/www.scientific.net/kem.385-387.321.

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Under the assumption that the viscosity coefficient is in inverse proportion to the power law of the equivalent plastic strain rate. The friction touch effect between viscosity and crack-tip surfaces is considered, the asymptotic solution is established for elastic-viscoplastic field at the mixed-mode quasi static crack-tip under compression and shear. The numerical solution at crack-tip without stress and stain gap is obtained. The variation of numerical solution is discussed for the mixed-mode under compression and shear according to each parameter. Through numerical results and analysis for the mixed-mode crack-tip field under compressing and shear, it is whole plastic without elastic unloaded section, viscosity effect is an important factor when propagating crack-tip field.

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Luo, Qiuhua, Qianying Zhang, and Puxiu Wang. "Hydrochlorothiazide/Losartan Potassium Tablet Prepared by Direct Compression." Pharmaceutics 14, no. 8 (August 21, 2022): 1741. http://dx.doi.org/10.3390/pharmaceutics14081741.

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Hydrochlorothiazide (HCTZ)/losartan potassium (LOS-K) was used as a model drug to prepare compound tablets through the investigation of the compression and mechanical properties of mixed powders to determine the formulation and preparation factors, followed by D-optimal mixture experimental design to optimize the final parameters. The type and amount of lactose monohydrate (SuperTab®14SD, 19.53–26.91%), microcrystalline cellulose (MCC PH102, 32.86–43.31%), pre-gelatinized starch (Starch-1500, 10.96–15.91%), and magnesium stearate (0.7%) were determined according to the compressive work, stress relaxation curves, and Py value. Then, the compression mechanism of the mixed powder was investigated by the Kawakita equation, Shapiro equation, and Heckel analysis, and the mixed powder was classified as a Class-II powder. The compaction pressure (150–300 MPa) and tableting speed (1200–2400 Tab/h) were recommended. A D-optimal mixture experimental design was utilized to select the optimal formulation (No 1, 26.027% lactose monohydrate, 32.811% MCC PH102, and 15.462% pregelatinized starch) according to the drug dissolution rate, using Hyzaar® tablets as a control. Following oral administration in beagle dogs, there were no significant differences in bioavailability between the No. 1 tablet and the Hyzaar® tablet in HCTZ, losartan carboxylic acid (E-3174), and LOS-K (F < F0.05). Thus, formulation and preparation factors were determined according to the combination of the compression and mechanical properties of the mixed powder and quality of tablets, which was demonstrated to be a feasible method in direct powder compression.

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Jeхenov M.K.,, Ismagilov F.R.,, Akhmetov S.M.,, Diarov M.,, and Bektay Y.K.,. "UTILIZATION OF HYDROGEN SULFIDE-CONTAINING REFINERY FLARE GASЕS." SERIES CHEMISTRY AND TECHNOLOGY 5, no. 443 (October 15, 2020): 64–70. http://dx.doi.org/10.32014/2020.2518-1491.81.

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Modern oil refinery flare does not provide the beneficial use of discharged hydrocarbon gases and vapors, which does not allow to reduce the volume of hydrocarbon gas burned in flare candles and reduce atmospheric pollution. To ensure a stable and trouble-free operation of the flare plant and to increase the efficiency of waste gas utilization, their preliminary compression using mechanical or jet compressors and the construction of gas treatment plants are required. A low-cost method of utilizing hydrogen sulfide-containing refinery gas is proposed, including two-stage gas compression by a liquid-ring compressor using an alkanolamine aqueous solution as a working fluid in the first stage of compression, separation of the compressor of first stage compression to produce desulfurized gas, hydrocarbon condensate and an alkanolamine saturated hydrogen sulfide. In the second stage, the compression of the desulfurized gas is carried out by a liquid-ring compressor using a hydrocarbon absorbent as the working fluid, cooling and separation of the compress of the second stage of compression produce lean gas, water condensate and absorbate. The aqueous condensate is mixed with saturated hydrogen sulfide alkanolamine absorbent and taken out for regeneration, the hydrocarbon condensate is mixed with the absorbate to produce BFLH, and the lean gas is subjected to membrane separation to produce hydrogen and fuel gas. Application of the method can partially cover the needs of refineries in hydrogen by reducing its losses, as well as return gas and hydrocarbon fractions for processing or to the fuel network of the plant.

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10

Mosti, Giovanni. "Compression in leg ulcer treatment: inelastic compression." Phlebology: The Journal of Venous Disease 29, no. 1_suppl (May 2014): 146–52. http://dx.doi.org/10.1177/0268355514526313.

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Compression therapy is extremely effective in promoting ulcer healing. Which material to use, if elastic or inelastic, is still a matter of debate. This paper will provide an overview on the recent findings in compression therapy mainly for venous or mixed ulcers which are the great majority of leg ulcers. In this paper it will be demonstrated that inelastic compression has been proved to be significantly more effective than elastic compression in reducing venous reflux, increasing venous pumping function and decreasing ambulatory venous hypertension. In addition it is comfortable, well accepted by patients and achieved an extremely high healing rate in venous ulcers. With reduced pressure inelastic compression is able to improve venous pumping function in patients with mixed ulcers without affecting but improving the arterial inflow. It will be also clearly shown that studies claiming a better effect of elastic compression compared to inelastic in favouring healing rate have significant methodological flaws making their conclusions at least doubtful. In conclusion inelastic- is significantly more effective than elastic compression in reducing ambulatory venous hypertension which is the main pathophysiological determinant of venous ulcers and demonstrated to be very effective in getting ulcer healing. New multicentric, randomized and controlled studies, without methodological flaws, will be necessary to prove that elastic- is at least as effective as inelastic compression or, maybe, more effective.

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Miki, Masaaki, and Toby Mitchell. "Interactive Exploration of Tension-Compression Mixed Shells." ACM Transactions on Graphics 41, no. 6 (November 30, 2022): 1–14. http://dx.doi.org/10.1145/3550454.3555438.

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Achieving a pure-compression stress state is considered central to the form-finding of shell structures. However, the pure-compression assumption restricts the geometry of the structure's plan in that any free boundary edges cannot bulge outward. Allowing both tension and compression is essential so that overhanging leaves can stretch out toward the sky. When performing tension-compression mixed form-finding, a problem with boundary condition (BC) compatibility arises. Since the form-finding equation is hyperbolic, boundary information propagates along the asymptotic lines of the stress function. If conflicting BC data is prescribed at either end of an asymptotic line, the problem becomes ill-posed. This requires a user of a form-finding method to know the solution in advance. By contrast, pure-tension or pure-compression problems are elliptic and always give solutions under any BCs sufficient to restrain rigid motion. To solve the form-finding problem for tension-compression mixed shells, we focus on the Airy's stress function, which describes the stress field in a shell. Rather than taking the stress function as given, we instead treat both the stress function and the shell as unknowns. This doubles the solution variables, turning the problem to one that has an infinity of different solutions. By enforcing equilibrium in the shell interior and prescribing the correct matching pairs of BCs to both the stress function and the shell, a stress function and shell can be simultaneously found such that equilibrium is satisfied everywhere in the shell interior and thus automatically has compatible BCs by construction. The problem of a potentially over-constrained form-finding is thus avoided by expanding the solution space and creating an under-determined problem. By varying inputs and repeatedly searching for stress function-shell pairs that fall within the solution space, a user is allowed to interactively explore the possible forms of tension-compression mixed shells under the given plan of the shell.

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12

Zhang, Peng, Haomin Song, Kaijun Rui, Juncai Li, and Shengnian Wang. "Effects of Soil Properties on the Performance of TRD Cut-Off Wall." Advances in Civil Engineering 2019 (August 21, 2019): 1–12. http://dx.doi.org/10.1155/2019/7098498.

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The trench cutting remixing deep wall (TRD) method is a new cement soil cut-off wall construction technique, which has been widely used in cofferdam, embankment dam, and underground waterproof curtain structures. The chain cutter of TRD moves horizontally to cut and stir different soil layers by up and down to form a cement-mixed soil diaphragm wall with continuous and uniform thickness, the mechanics and permeability of which are obviously different from those of cement soil with a horizontally mixed single soil layer in traditional deep mixing pile (DMP). In this paper, five sets of onsite walling tests with different cement ratios were carried out to analyse the unconfined compression and permeability of undisturbed cement-mixed soil in TRD. The difference of both unconfined compressive and permeability coefficients in between TRD and DMP was analysed to discuss the stirring performance of TRD. Then, the microscopic mechanism of soil properties affecting the performance of cement-mixed soil has been studied by scanning electron microscopy (SEM) in the unconfined compression strength test and permeability coefficient test of cement soil with different mixed soil properties. The test results show that the unconfined compressive strength of cement-mixed soil is closely correlated to its gradation. As the mixed soil gradation curve approaches to the Fuller curve, the unconfined compressive strength would gradually increase. In mesoscopic, cement fine sand has a large pore structure, and the average pore area is 2.46 times as cement clay. The permeability coefficient of cement-mixed soil is controlled by the proportion of fine sand content with high permeability.

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Neauport, J., N. Bonod, S. Hocquet, S. Palmier, and G. Dupuy. "Mixed metal dielectric gratings for pulse compression." Optics Express 18, no. 23 (October 27, 2010): 23776. http://dx.doi.org/10.1364/oe.18.023776.

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Petrov, Peter, and Paul Joos. "Linear Compression of a Mixed Adsorbed Monolayer." Journal of Colloid and Interface Science 182, no. 1 (September 1996): 179–89. http://dx.doi.org/10.1006/jcis.1996.0449.

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Kotteda, V. M. Krushnarao, and Sanjay Mittal. "Viscous flow in a mixed compression intake." International Journal for Numerical Methods in Fluids 67, no. 11 (October 7, 2010): 1393–417. http://dx.doi.org/10.1002/fld.2423.

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Austin, N., P. M. Diaz, D. S. Manoj Abraham, and N. Kanthavelkumaran. "Environment Friendly Mixed Refrigerant to Replace R-134a in a VCR System with Exergy Analysis." Advanced Materials Research 984-985 (July 2014): 1174–79. http://dx.doi.org/10.4028/www.scientific.net/amr.984-985.1174.

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Study on environment friendly mixed refrigerant to replace R134a in vapour compression refrigeration (VCR) System. The mixed refrigerants investigated are propane (R290), butane (R600), isobutene (R600a) and R134a. Even though the ozone depletion potentials of R134a relative to CFC-11 are very low; the global warming potentials are extremely high and also expensive. For this reason, the production and use of R134a will be terminated in the near future. Hydrocarbons are free from ozone depletion potential and have negligible global warming potential. The results showed that, mixed refrigerant with charge of 80 g satisfy the required freezer air temperature when R134a with a charge of 110 g is used as refrigerant. The actual COP of refrigerator using mixed refrigerant was almost nearer that of the system using R134a as refrigerant. The coefficient of performance of the vapour compression refrigeration system using mixed refrigerant MR-3 [R134a/R290/ R600a/ R600 (20/35/40/5)] is having very close value with R134a and the Global warming potential of MR-3 is negligible when compared with R134a. Hence the mixed refrigerant MR-3 is chosen as an environmental friendly alternate refrigerant to R134a. The exergy analysis of the vapour compression refrigeration system using R134a and all the above mixtures are investigated. The effect of evaporator temperature on exergy efficiency and exergy destruction ratio of the system are experimentally studied. The exergy defect in the compressor, condenser, expansion device and evaporator are also obtained. Key words: R134a, Mixed refrigerant, Chlorofluorocarbons, Propane, Butane, Isobutene, REFPROP, COP, ODP, GWP, Exergy, VCR System.

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Vivek, P., and Sanjay Mittal. "Buzz Instability in a Mixed-Compression Air Intake." Journal of Propulsion and Power 25, no. 3 (May 2009): 819–22. http://dx.doi.org/10.2514/1.39751.

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SHETTY, D. K., A. R. ROSENFIELD, and W. H. DUCKWORTH. "Mixed-Mode Fracture of Ceramics in Diametral Compression." Journal of the American Ceramic Society 69, no. 6 (June 1986): 437–43. http://dx.doi.org/10.1111/j.1151-2916.1986.tb07441.x.

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Jain, Manish Kumar, and Sanjay Mittal. "Euler flow in a supersonic mixed-compression inlet." International Journal for Numerical Methods in Fluids 50, no. 12 (2006): 1405–23. http://dx.doi.org/10.1002/fld.1109.

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Shahmohamadi, H., R. Rahmani, H. Rahnejat, C. P. Garner, and P. D. King. "Thermo-Mixed Hydrodynamics of Piston Compression Ring Conjunction." Tribology Letters 51, no. 3 (June 4, 2013): 323–40. http://dx.doi.org/10.1007/s11249-013-0163-5.

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Wang, Chen, and Wentao Li. "Factors Affecting the Mechanical Properties of Cement-Mixed Gravel." Advances in Materials Science and Engineering 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/8760325.

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A study has been conducted to investigate the mechanical properties of cement-mixed gravel using the unconfined compression test and the tensile test. Basic factors including the curing period, the water-binder ratio, the cement content, and the strain rate were evaluated. Ordinary Portland cement with fly ash was employed as the cementation agent for preparing cemented samples. The results indicate that the unconfined compressive strength, the deformation modulus, and the tensile strength increase with the increase in the curing period. The ratio of tensile strength to unconfined compressive strength has no distinct change after 7 days. An optimum water-binder ratio can be obtained. The unconfined compressive strength and deformation modulus decrease as the water-binder ratio decreases and increase from the optimum water-binder ratio. With the increasing of the cement content, the unconfined compressive strength increases distinctly, the deformation modulus increases significantly when the cement content is less than 4% and then increased slowly, and the failure strain increases to a peak value and then decreases. With the increasing of the strain rate, the unconfined compressive strength increases slightly and the deformation modulus increases slowly. The failure strain decreases with an increase in the strain rate.

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Fartini, M. S., M. S. Abdul Majid, Mohd Afendi, R. Daud, and Azizul Mohamad. "Effect of Nano-Clay and their Dispersion Techniques on Compressive Properties of Unsaturated Polyester Resin." Applied Mechanics and Materials 554 (June 2014): 27–31. http://dx.doi.org/10.4028/www.scientific.net/amm.554.27.

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This paper aims to understand the relationship between processing parameters and compressive properties of nanoclay filled polyester resin (dispersion method and wt% of nanoclay particles). Unsaturated polyester resin with 0-5 wt% nanoclay content was prepared by hand mixing and through shears mixing of water bath shaker. Static uniaxial compression tests were conducted to investigate how the unsaturated polyester resins with nanoclay contents and processing will effect on the compressive stress-strain behaviour and compression properties. The experimental results show that the compressive strength and elastic modulus of nanomodified resin are significantly affected by type of mixing methods to prepare the specimens and the ratio of nanoparticles content during mixing. It was found out that the compressive strength and compressive modulus increase with the nanoclay content. The findings also indicate the dispersion of nanoclay by hand-mixed method yield higher compressive strength compared to that dispersed by water shaker bath.

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Bakshi, Suhaib. "Effects of Disparate Zones of Sand on the Compressive Strength of Concrete." International Journal for Research in Applied Science and Engineering Technology 9, no. 11 (November 30, 2021): 1368–75. http://dx.doi.org/10.22214/ijraset.2021.39023.

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Abstract: Compressive strength of concrete is the capacity of concrete to bear loads of materials or structure sans breaking or being deformed. Specimen under compression shrinks in size whilst under tension the size elongates. Compressive strength essentially gives concept about the properties of concrete. Compressive strength relies on many aspects such as water-cement ratio, strength of cement, calidad of concrete material. Specimens are tested by compression testing machine after the span of 7 or 28 days of curing. Compressive strength of the concrete is designated by the load on the area of specimen. In this research various proportions of such aggregate mixed in preparing M 30 grade and M 40 grade of Concrete mix and the effect is studied on its compressive strength . Several research papers have been assessed to analyze the compressive strength of concrete and the effect of different zones of sand on compressive strength are discussed in this paper. Keywords: Sand, Gradation, Coarse aggregate, Compressive strength

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Misra, R. S. "Irreversibility Reduction in Vapour Compression Refrigeration Systems Using Al2O3 Nano Material Mixed in R718 as Secondary Fluid." International Journal of Advance Research and Innovation 3, no. 2 (2015): 127–35. http://dx.doi.org/10.51976/ijari.321528.

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The several methods are available in the literature for improving first law efficiency in terms of coefficient of performance. The second law efficiency is helped for finding the irreversibilities the systems. The uses of nano refrigerants in the vapour compression refrigeration play a very important role for reducing irreversibility in the system and improving its thermodynamic performances. This paper describes thermal modelling of vapour compression refrigeration system using energy - exergy analysis. In this system, the utility of ecofriendly twelve refrigerants in primary circuit is highlighted and Al2O3-Water based nanofluids in secondary circuit. This model takes care the nanoparticles mixed in the fluids as input conditions in the secondary evaporator circuit as geometric characteristics of the system such as size of nanoparticles and the compressor speed to predict the secondary fluids output temperatures, the operating pressures, the compressor power consumption and the system overall energy performance. Such design analysis is conveniently useful to compare the thermal performance of different nano-particles of Al2O3 based nano-fluid as a secondary fluid in a vapour compression refrigeration system. The influence of input variables on the irreversibilities in terms of exergy destruction ratio of the system is presented. Such a model can also be used to design various components viz. evaporator, compressor, condenser and throttle valve for vapour compression refrigeration systems for any desired cooling capacity. This model takes care of use of nanofluids as a secondary fluid in vapour compression refrigeration systems and simulate the non linear equations of the system. The use of R407c as ecofriendly refrigerants is quite adequate while first law performance improvement is around 13.491% by using nano particles. The % improvement in first law efficiency is found to be 11.04% by using nano particles as compared to without nano particles. While by using R134a 12.60% improvement. Similarly It was also observed that second law performance improvement is ranging between 15% to 39.13%. The better second law efficiency is 39.13% improvement due to, by using R1234yf as compared to 16.52% improvement by using R1234ze in the primary evaporator circuit. The reduction in the irreversibility in terms of exergy destruction ratio in the system and maximum exergy destruction ratio around 25.294% was observed by using R152a and exergy destruction ratio is 22.79% by using R290 hydrocarbon and 23.403% by using R407c as ecofriendly refrigerant. The Reduction in EDR is 20.09% by using R404a, and 21.37% by using R134a. The R1234ze and R1234yf have slightly less reduction in EDR as compared by using R134a.

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Flock, Andreas K., and Ali Gülhan. "Modified Kantrowitz Starting Criteria for Mixed Compression Supersonic Intakes." AIAA Journal 57, no. 5 (May 2019): 2011–16. http://dx.doi.org/10.2514/1.j057283.

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Mekuria, Rufael. "Network streaming and compression for mixed reality tele-immersion." ACM SIGMultimedia Records 8, no. 4 (July 28, 2017): 1. http://dx.doi.org/10.1145/3129151.3129159.

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Stansal, A., E. Tella, A. Yannoutsos, I. Keita, R. Attal, V. Gautier, D. Sfeir, I. Lazareth, and P. Priollet. "Supervised short-stretch compression therapy in mixed leg ulcers." JMV-Journal de Médecine Vasculaire 43, no. 4 (July 2018): 225–30. http://dx.doi.org/10.1016/j.jdmv.2018.05.006.

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Saad, Sameh M. I., Zdenka Policova, Edgar J. Acosta, Michael L. Hair, and A. Wilhelm Neumann. "Mixed DPPC/DPPG Monolayers at Very High Film Compression." Langmuir 25, no. 18 (September 15, 2009): 10907–12. http://dx.doi.org/10.1021/la901250z.

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Zavos, Anastasios, and Pantelis G. Nikolakopoulos. "Cavitation effects on textured compression rings in mixed lubrication." Lubrication Science 28, no. 8 (May 31, 2016): 475–504. http://dx.doi.org/10.1002/ls.1341.

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30

Liang, Huaguo, Sybille Hellebrand, and Hans-Joachim Wunderlich. "A mixed-mode BIST scheme based on folding compression." Journal of Computer Science and Technology 17, no. 2 (March 2002): 203–12. http://dx.doi.org/10.1007/bf02962213.

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31

Kotteda, V. M. Krushnarao, and Sanjay Mittal. "Computation of turbulent flow in a mixed compression intake." International Journal of Advances in Engineering Sciences and Applied Mathematics 6, no. 3-4 (December 2014): 126–41. http://dx.doi.org/10.1007/s12572-014-0115-9.

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32

Farhana, Z. F., H. Kamarudin, Azmi Rahmat, and A. M. Mustafa Al Bakri. "A Study on Relationship between Porosity and Compressive Strength for Geopolymer Paste." Key Engineering Materials 594-595 (December 2013): 1112–16. http://dx.doi.org/10.4028/www.scientific.net/kem.594-595.1112.

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This paper presents a study on the relationship between porosity and compressive strength for geopolymer paste. In this research, geopolymer paste was made from fly ash class F based geopolymer mixed with alkaline activator; sodium hydroxide solution and sodium silicate solution. Twelve mixes were cast in 50mm x 50mm x 50mm moulds and the samples were cured for 24 hrs at 60 °C in the oven. The samples were examined after 7, 14, 28 and 90 days in terms of porosity test, pulse velocity test and compressive strength test. It was concluded that the sample at day 90 had the highest compressive strength of 56.50 N/mm2had porosity 3.77%. Thus, the sample with lowest porosity had highest pulse velocity 3303 m/s during ultrasonic testing with lowest transmission time 15.17 μs. Keywords: porosity, compression strength, geopolymer, pulse velocity

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Zavos, Anastasios, and Pantelis Nikolakopoulos. "Thermo-mixed lubrication analysis of coated compression rings with worn cylinder profiles." Industrial Lubrication and Tribology 69, no. 1 (January 9, 2017): 15–29. http://dx.doi.org/10.1108/ilt-11-2015-0169.

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Purpose Compression rings are the main sources of frictional losses in internal combustion engines. The present paper aims to present a thermo-mixed hydrodynamic analysis for coated top compression rings. To understand the coating effects, the main tribological parameters are investigated into a ring-cylinder conjunction in a motorbike engine. Furthermore, flow simulations have been carried out on how different worn profiles on the cylinder inner liner affects friction, lubricant film and localized contact deformation of the coated compression rings. Design/methodology/approach In this paper, the basic geometrical dimensions of the top compression ring-cylinder system are obtained from a real motorbike engine. A 2D axisymmetric CFD/FLOTRAN model is created for coated compression rings. Flow simulations are performed by solving the Navier-Stokes and the energy equations. The load capacity of the asperities is also taken into account by Greenwood and Tripp contact model. Realistic boundary conditions are imposed to simulate the in-plane ring motion. The simulation model is validated with analytical and experimental data from the literature. Under thermal considerations, the contribution of worn cylinder profiles in conjunction with different coated compression rings is presented. Findings This research shows that because of thermal effects, the boundary friction is higher at reversals and the viscous friction is lower because of reduced oil viscosity. As regards to the isothermal case, the viscous friction is greater because of a higher lubricant viscosity. In the case of chromium-plated ring, boundary friction was 16 per cent lower than a grey cast iron ring taking into account thermal effects. Regarding the localized contact deformation, the coated compression rings showed lower values under different worn cylinder shapes. In particular, hard wear-resistant (Ni-Cr-Mo) coating showed the slighter local deformation. Therefore, the worn cylinder profiles promote boundary/mixed lubrication regime, whereas the lobed profile of cylinder inner liner becomes more wavy. Originality/value The solution of the thermo-mixed lubrication model, concerning the piston ring and worn cylinder tribo pair by taking into account the coating of the top compression ring.

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Dhiman, Pankaj, Dushyant Kaistha, and Shabnam Dhiman. "Effect of Capillary Tube Shapes on The Performance of Vapour Compression Refrigeration Cycle Using Nano-Refrigerant." International Journal for Research in Applied Science and Engineering Technology 10, no. 8 (August 31, 2022): 1740–47. http://dx.doi.org/10.22214/ijraset.2022.46501.

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Abstract: The main aim of this experimental study was to check the coefficient of performance on the Vapour Compression Refrigeration System by changing the shape of the capillary tube and by changing the refrigerants. Investigated the effect of Nano Refrigerant on the Coefficient Of Performance of Vapour Compressor Refrigeration Cycle. Compared the Coefficient Of Performance on the basis of R-22 (Difluoro-Monochloro Methane (CHF2CL) or R-22) and Al2O3 Nano particles mixed R22.The shape of the capillary tubes and the refrigerants is altered to study its effect on the performance of vapour compression refrigeration cycle. The shapes of Capillary tubes used were Serpentine Shape and Cubic Shape.

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Hinchberger, S., J. Weck, and T. Newson. "Mechanical and hydraulic characterization of plastic concrete for seepage cut-off walls." Canadian Geotechnical Journal 47, no. 4 (April 2010): 461–71. http://dx.doi.org/10.1139/t09-103.

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This paper describes a series of laboratory tests performed to characterize the mechanical and hydraulic properties of plastic concrete (PL-C). PL-C is used in the construction of seepage cut-off walls in dams and it comprises cement, aggregate, and water mixed with sodium bentonite. The addition of sodium bentonite causes a reduction in strength and improved ductility after failure compared with normal concrete. The mechanical properties of PL-C are studied using a series of unconfined compression tests and confined compression tests performed while simultaneously permeating water through PL-C specimens. Stress relaxation and controlled rate of loading tests are also performed to investigate the rate-sensitivity and time-dependency of plastic concrete. The test results show that the hydraulic conductivity of PL-C increases between two and three orders of magnitude during triaxial compression due to yielding, crack formation, and dilation of the cracks. Such changes in the behaviour of PL-C should be minimized during design by controlling the working strains and using erosion-resistant mixes. In addition to these findings, PL-C exhibits significant time-dependent behaviour similar to that observed for clays, and the variation of compressive strength versus confining stress is comparable to normal strength concrete.

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Gyawali, Tek Raj. "Mixing of High Ductile Mortar (HDM) in Concrete Mixers." Journal of Engineering Technology and Planning 1 (December 1, 2019): 1–10. http://dx.doi.org/10.3126/joetp.v1i0.38238.

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Plain concrete is strong in compression, but very weak in tension. Tensile strength of plain concrete is about10 to 15% of the compressive strength depending upon the grade of concrete. Another limitation of plain concrete is that it is brittle in failure. Fiber-reinforced concrete (FRC) is the concrete made primarily of hydraulic cements, aggregates, and discrete reinforcing fibers. Fibers suitable for reinforcing concrete are produced from steel, glass, and organic polymers (synthetic fibers). Author hereby has attempted to develop the High Ductile Mortar (HDM) using Poly Vinyl Alcohol (PVA) fibers. HDM may replace the steel fibers to increase the flexural strength and deflection. It also lightens the structure than steel fiber reinforced concrete (SFRC). This paper gives the brief history of HDM development results which were mixed in small mortar mixer of 10 liter capacity. Then, it presents the results of HDM mixed in two different concrete mixers of 100 liter capacity using different PVA fibers and sands.

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Chen, Yu, Fenghong Cao, Chi Deng, Yong Zhang, Minggang Jiang, Zubin Xiong, Fulong Shi, et al. "Effect of compression loading speeds on the room temperature mechanical properties of as-extruded AZ31 magnesium alloy." Journal of Physics: Conference Series 2174, no. 1 (January 1, 2022): 012065. http://dx.doi.org/10.1088/1742-6596/2174/1/012065.

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Abstract The room temperature compression experiments of as-extruded AZ31 magnesium alloy under different loading speeds were carried out on a universal tensile testing machine. The fracture failure characteristics and mechanism of the alloy under different compression loading speeds were analyzed by scanning electron microscope (SEM) and optical microscope (OM). The results show that during the compression test, the crushed AZ31 magnesium alloy sample has a certain pier coarseness, the macro fracture of the sample is located at one third of the sample, and the macro fracture mode is 45° shear fracture with the sample axis; With the increase of loading speed, the coincidence degree of macro fracture becomes worse, and its compressive strength changes in an undulating manner. When the loading speed is 2mm/min, the compressive strength reaches the peak value of 413MPa, and the fracture morphology of the sample shows a typical flat and flat rock like ductile brittle mixed fracture. With the increase of loading speed, the proportion of brittle fracture components increases, the shape of shrinkage fracture is rock like fracture, and the fracture fluctuation is relatively slow, the dimples distributed on the fracture surface are elongated and torn, and the compression speed has no obvious effect on the fracture morphology.

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Wang, Zhen Qing, Fang Liu, and Wen Yan Liang. "The Elastic-Viscoplastic Field at the Mixed-Mode Crack-Tip under Compression and Shear." Advanced Materials Research 211-212 (February 2011): 364–68. http://dx.doi.org/10.4028/www.scientific.net/amr.211-212.364.

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To further study the field of the mixed-mode interface crack tip under compression and shear, we analyze the problem on the quasi-static propagating of the interface crack theoretically and numerically.In this paper,we assumes that the artifical viscosity cofficient is in inverse proportion to power law of the plastic strain rate,and the stress of the interface crack possesses power law singularity. The viscosity of material,the friction touch effection of the crack-tip surface and the load hybrid parameter are considered. The asymptotic solution is established for elastic-viscoplastic field at the mixed-mode propagating crack-tip under comprission and shear.It is shown in numerical results and analysis that for the mixed-mode crack-tip field under compressing and shear is whole plastic without elastic unloaded section;viscosity effection is an important factor when propagating crack-tip field is studied; viscosity coefficient, mach number and singularity exponent are the control factors of singular field at the crack-tip.

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Jin, Chao, Tianyun Sun, Teng Xu, Xueli Jiang, Min Wang, Zhao Zhang, Yangyi Wu, Xiaoteng Zhang, and Haifeng Liu. "Influence of Glycerol on Methanol Fuel Characteristics and Engine Combustion Performance." Energies 15, no. 18 (September 8, 2022): 6585. http://dx.doi.org/10.3390/en15186585.

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Methanol derived from solar energy is a carbon-neutral alternative fuel for engines. The low viscosity of methanol is one of the problems that restrict its direct compression ignition application in engines. Glycerol is a renewable resource derived from biomass, and its viscosity is more than 1700 times that of methanol. In this study, glycerol was mixed with methanol in different volume fractions (1–50%), and a methanol-glycerol mixture with similar viscosity to diesel was prepared. Then, the particle size, electrical conductivity, viscosity, swelling and corrosion characteristics of the mixed fuel were measured. Finally, the combustion and emission tests of methanol-glycerol mixed fuel were carried out on a heavy-duty multi-cylinder diesel engine. The results show that glycerol can effectively adjust the viscosity of the mixed fuel. The viscosity of the mixed fuel can reach 3.19 mm2/s at 20 °C when blended with 30% glycerol by volume, which meets the requirements of the national standard for diesel fuel. The addition of glycerol can alleviate the corrosion of methanol to the polymer. The test of the mixed fuel in the direct compression ignition engine shows that the thermal efficiency of methanol mixed with 5% glycerol was further improved than that of pure methanol, both of which were significantly higher than the thermal efficiency of diesel compression ignition engines. Methanol and 5% glycerol by volume blends can reduce soot and nitrogen oxide emissions while maintaining low HC and CO emissions. Therefore, proper blending of glycerol in methanol fuel can optimize the fuel properties of methanol and achieve higher thermal efficiency and lower pollutant emissions than pure methanol direct compression ignition.

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Chen, Guang, Changcai Zhao, Haiwei Shi, Qingxing Zhu, Guoyi Shen, Zheng Liu, Chenyang Wang, and Duan Chen. "Research on the 2A11 Aluminum Alloy Sheet Cyclic Tension–Compression Test and Its Application in a Mixed Hardening Model." Metals 13, no. 2 (January 26, 2023): 229. http://dx.doi.org/10.3390/met13020229.

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The increasing application of aluminum alloy, in combination with the growth in the complexity of components, provides new challenges for the numerical modeling of sheet materials. The material elastic–plasticity constitutive model is the most important factor affecting the accuracy of finite element simulation. The mixed hardening constitutive model can more accurately represent the real hardening characteristics of the material plastic deformation process, and the accuracy of the material property-related parameters in the constitutive model directly affects the accuracy of finite element simulation. Based on the Hill48 anisotropic yield criterion, combined with the Voce isotropic hardening model and the Armstrong–Frederic nonlinear kinematic hardening model, a mixed hardening constitutive model that considers material anisotropy and the Bauschinger effect was established. Analysis of the tension–compression experiment on the sheet using finite element method. Using the finite element model, the optimum geometry of the tension–compression experiment sample was determined. The cyclic deformation stress–strain curve of the 2A11 aluminum alloy sheet was obtained by a cyclic tensile–compression test, and the material characteristic parameters in the mixed hardening model were accurately determined. The reliability and accuracy of the established constitutive model of anisotropic mixed hardening materials were verified by the finite element simulation and by testing the cyclic tensile–compression problem, the springback problem, and the sheet in bending, unloading, and reverse bending problems. The tensile–compression experiment is an effective method to directly and accurately obtain the characteristic parameters of constitutive model materials.

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Kubík, Ľubomír, Viera Kažimírová, Monika Božiková, Tomáš Giertl, and Štefan Mihina. "Correlation of the colour of straw fuel pellets to the compressive properties." Journal on Processing and Energy in Agriculture 25, no. 1 (2021): 7–12. http://dx.doi.org/10.5937/jpea25-31141.

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The aim of the manuscript was the evaluation of the compressive properties of straw pellets in relation to the colour differences between them. Modulus of elasticity and failure strength of the pellets at the compression were determined. A testing machine Andilog Stentor 1000 (Andilog Technologies, Vitrolles, France) was employed for uniaxial compression tests. L*, a*, b* colour coordinates of CIE LAB 3D colour space were used for the characterization of the pellet's colour. Two sorts of pellets were measured: made from wheat straw and made from the mixed wheat and barley straw. Samples were measured by a spectrophotometer 3NH YS3020 and computed as the mean of twenty samples. The correlation of the pellet colour with the mechanical properties, mainly modulus of elasticity and failure strength of the pellets at the compression were realized to obtain a relation of the deformation process to the pellet's colour of different sorts of pellets.

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Dexenov, M. K., and F. R. Ismagilov. "Utilization of Emissions from Reactors of a Delayed Coking Installation." Ecology and Industry of Russia 24, no. 11 (November 18, 2020): 4–9. http://dx.doi.org/10.18412/1816-0395-2020-11-.

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The features of utilization of low-pressure gas emissions from reactors of a delayed coking installation are considered. A technical solution has been proposed for the compression and purification of low-pressure hydrocarbon gases from hydrogen sulfide by using a liquid-ring compressor with an amine solution mixed with a hydrocarbon fraction taken in a certain ratio as a working liquid. Gasolines, kerosene, diesel fuels and any other hydrocarbon mixtures with low viscosity can be used as the hydrocarbon fraction. Preferably use gaseous gasoline obtained during the compression of gas or distillate in the main distillation column. Test results and computational studies confirm the advantages of using a binary working fluid compared to using the components separately.

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Dexenov, M. K., and F. R. Ismagilov. "Utilization of Emissions from Reactors of a Delayed Coking Installation." Ecology and Industry of Russia 24, no. 11 (November 18, 2020): 4–9. http://dx.doi.org/10.18412/1816-0395-2020-11-4-9.

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The features of utilization of low-pressure gas emissions from reactors of a delayed coking installation are considered. A technical solution has been proposed for the compression and purification of low-pressure hydrocarbon gases from hydrogen sulfide by using a liquid-ring compressor with an amine solution mixed with a hydrocarbon fraction taken in a certain ratio as a working liquid. Gasolines, kerosene, diesel fuels and any other hydrocarbon mixtures with low viscosity can be used as the hydrocarbon fraction. Preferably use gaseous gasoline obtained during the compression of gas or distillate in the main distillation column. Test results and computational studies confirm the advantages of using a binary working fluid compared to using the components separately.

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Attaran, Robert R., and Cassius I. Ochoa Chaar. "Compression therapy for venous disease." Phlebology: The Journal of Venous Disease 32, no. 2 (July 9, 2016): 81–88. http://dx.doi.org/10.1177/0268355516633382.

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For centuries, compression therapy has been utilized to treat venous disease. To date it remains the mainstay of therapy, particularly in more severe forms such as venous ulceration. In addition to mechanisms of benefit, we discuss the evidence behind compression therapy, particularly hosiery, in various forms of venous disease of the lower extremities. We review compression data for stand-alone therapy, post-intervention, as DVT prevention, post-thrombotic syndrome and venous ulcer disease. We also review the data comparing compression modalities as well as the use of compression in mixed arteriovenous disease.

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Elmegreen, Bruce, Binquan Luan, Rodrigo Neumann Barros Ferreira, and Breanndan O’Conchuir. "A method for near-perfect gas separation in two interconnected streams." Journal of Applied Physics 133, no. 1 (January 7, 2023): 015001. http://dx.doi.org/10.1063/5.0127983.

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Gas separation such as CO[Formula: see text] from N[Formula: see text] in flue gas is an important step in reducing greenhouse gas emission. We discuss a separation method that moves mixed gas between two tracks at different pressures with ever-increasing purity at each stage along the tracks. Designs for adsorbents driven by volumetric pumps and membranes driven by a pressure drop are illustrated. For selectivity exceeding 10 in a three-stage system, the purity of the CO[Formula: see text] output is 97.8% with 99.75% recovered. For a six-stage example, the purity of CO[Formula: see text] is 99.996% and 99.9996% is recovered. The cost of compression is estimated from the number of times the two components have to be pressurized as they move between the tracks. For large selectivity, the effective number of times for CO[Formula: see text] is 2 for the adsorbent case and 3 for the membranes in the three-stage design; these numbers are 5 and 6 in the six-stage design. As a result, the compressional energy requirement per input mole is [Formula: see text] in the isothermal case for compression factor [Formula: see text], effective number of re-compressions [Formula: see text], and input CO[Formula: see text] fraction [Formula: see text]. This compressional energy exceeds the minimum energy from entropy by the factor [Formula: see text] if [Formula: see text] for efficient membrane use.

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Zhou, Chao, Can Chen, Fei Ding, and Dengyin Zhang. "Distributed Compressive Video Sensing with Mixed Multihypothesis Prediction." Mathematical Problems in Engineering 2018 (November 7, 2018): 1–10. http://dx.doi.org/10.1155/2018/7020828.

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Traditional video acquisition systems require complex data compression at the encoder, which makes them unacceptable for resource-limited applications such as wireless multimedia sensor networks (WMSNs). To address this problem, distributed compressive video sensing (DCVS) represents a novel sensing approach with a simple encoder. This method shifts the computational burden from the encoder to the decoder and needs a robust reconstruction algorithm. In this paper, a mixed measurement-based multihypothesis (MH) reconstruction algorithm (mixed-MH) is proposed for DCVS to improve the reconstruction quality at low sampling rates. Considering the inaccuracy of MH prediction when measurements are insufficient, the available side information (SI) is resampled to obtain the artificial measurements, which are then integrated into real measurements via regularization. Furthermore, to avoid the negative effect of SI at high sampling rates, an adaptive regularization parameter is designed to balance the contributions of real and artificial measurements at different sampling rates. The experimental results demonstrate that the proposed mixed-MH prediction scheme outperforms other state-of-the-art algorithms in the reconstruction quality at the same low sampling rate.

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Dong, Xiao Qiang, Xin En Huang, Xiao Hong Bai, and Yong Kang Lv. "Experimental Study on the Unconfined Compression Strength of Cemented Soil Contaminated by Municipal Sewage." Applied Mechanics and Materials 121-126 (October 2011): 2754–58. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.2754.

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Contamination can change the physical properties of soil, reduce the strength of cemented soil foundation, and then induce the instability or disruption of buildings. This study explored the relationships among the age, electrical resistivity, unconfined compression strength, contamination of municipal sewage concentration. Firstly, we mixed the silty clay with municipal sewage of five different concentrations to form the contaminated soil. Then, mixed the contaminated soil with ordinary portland cement to form the cemented soil blocks. Finally, measured the unconfined compression strength and electrical resistivity of these blocks. The results show that the unconfined compression strength and electrical resistivity increase linearly with the increase of the logarithm of age, and decrease exponentially with the increase of municipal sewage concentration. The unconfined compression strength of cemented soil has a linear relationship with its resistivity. The municipal sewage concentration and age can be use to predict the unconfined compression strength of cemented soil.The predicted values correlate well with the experimental values.

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Juanita, Juanita. "PENINGKATAN NILAI KUAT TEKAN DAN PERBAIKAN RETAK-RETAK PADA BETON DENGAN MENGGUNAKAN FIBER KAWAT BENDRAT BENTUK “Z” DENGAN 3 (TIGA) VARIASI CAMPURAN." J-ENSITEC 8, no. 01 (January 29, 2022): 619–23. http://dx.doi.org/10.31949/jensitec.v8i01.1982.

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Concrete is the main basic material used for the planning and design of widely used structures. This is because concrete has a very high compressive strength value when compared to other materials. However, concrete also has weaknesses, one of which is its brittle nature. Therefore, in this study, the use of Z-shaped bendrat wire will be carried out to increase the value of the compressive strength of concrete while improving the brittle nature of the concrete.In this study, bendrat wire fiber in the form of Z was used with a mixed variation of 0.5%, 0.75% and 1%. The number of test objects made is 12 pieces. The test was carried out when the specimen was 28 days old by using a Compression Testing Machine (CTM). From the results of the study, the average compressive strength value for normal concrete (SN) was 26.46 MPa, for Z-shaped bendrat wire fiber concrete with a mixed variation of 0.5% (SF1) the average compressive strength value was 27.27 MPa, for fiber concrete bendrat wire Z shape with a mixed variation of 0.75% (SF2) the average compressive strength value is 28.03 MPa, and for fiber concrete wire bendrat Z shape with a mixed variation of 1% (SF3) the average compressive strength value is 28.21 MPa. The more Z-shaped bendrat wire fibers added to the concrete mix, the higher the compressive strength value and the smaller the cracks that occur in the concrete.

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AVERBUCH, AMIR Z., VALERY A. ZHELUDEV, MOSHE GUTTMANN, and DAN D. KOSLOFF. "LCT-WAVELET BASED ALGORITHMS FOR DATA COMPRESSION." International Journal of Wavelets, Multiresolution and Information Processing 11, no. 05 (September 2013): 1350032. http://dx.doi.org/10.1142/s021969131350032x.

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We present an algorithm that compresses two-dimensional data, which are piece-wise smooth in one direction and have oscillatory events in the other direction. Fine texture, seismic, hyper-spectral and fingerprints have this mixed structure. The transform part of the compression process is an algorithm that combines the application of the wavelet transform in one direction with the local cosine transform (LCT) in the other direction. This is why it is called hybrid compression. The quantization and the entropy coding parts in the compression process were taken from SPIHT codec but it can also be taken from any multiresolution based codec such as EZW. To efficiently apply the SPIHT codec to a mixed coefficients array, reordering of the LCT coefficients takes place. When oscillating events are present in different directions as in fingerprints or when the image comprises of a fine texture, a 2D LCT with coefficients reordering is applied. These algorithms outperform algorithms that are solely based on the the application of 2D wavelet transforms to each direction with either SPIHT or EZW coding including JPEG2000 compression standard. The proposed algorithms retain fine oscillating events including texture even at a low bitrate. Its compression capabilities are also demonstrated on multimedia images that have a fine texture. The wavelet part in the mixed transform of the hybrid algorithm utilizes the Butterworth wavelet transforms library that outperforms the 9/7 biorthogonal wavelet transform.

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Alexander, Derrick C., Jean P. Sislian, and Bernard Parent. "Hypervelocity Fuel/Air Mixing in Mixed-Compression Inlets of Shcramjets." AIAA Journal 44, no. 10 (October 2006): 2145–55. http://dx.doi.org/10.2514/1.12630.

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Journal articles on the topic 'Mixed Compression'

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