The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
Changan Wang - One of the best experts on this subject based on the ideXlab platform.
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effect of sintering temperature on compressive strength of porous yttria stabilized zirconia ceramics
Ceramics International, 2010Co-Authors: Liangfa Hu, Changan WangAbstract:Abstract Porous yttria-stabilized zirconia (YSZ) ceramics were fabricated by tert-butyl alcohol (TBA)-based gel-casting method for potential applications in heat-insulation materials. The effect of sintering temperature on compressive strength of porous YSZ ceramics was investigated on the basis of measurements Linear Shrinkage, porosity and pore size. As the sintering temperature increased from 1350 to 1550 °C, a decrease of porosity from 77 to 65%, a decrease of average pore size from and an increase of Linear Shrinkage from 15.4 to 31.8% were observed. The compressive strength increased remarkably from 3 to 27 MPa with increasing sintering temperature from 1350 to 1550 °C, which was related to the corresponding change of Linear Shrinkage, porosity, pore size and microstructure. A remarkable decrease of compressive strength with increasing porosity was observed. The compressive strength decreased also with increasing pore size.
Okechukwu Pius Aghamelu - One of the best experts on this subject based on the ideXlab platform.
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Engineering Behaviour of Cement-Treated Expansive Subgrade Soils from Awgu, Southeastern Nigeria
Civil and environmental research, 2015Co-Authors: O.c. Okeke, O.i. Imasuen, C O Okogbue, Okechukwu Pius AghameluAbstract:Engineering behaviour of cement-treated expansive soils refers to changes in the engineering properties of the soil in terms of reduction in values of swelling indicators and increase in values of strength characteristics of the soil when it is treated with various percentages of cement. In this study, engineering properties including liquid limit, plasticity index, Linear Shrinkage, maximum dry density/optimum moisture content, and California Bearing Ration (CBR) of expansive subgrade soils from Awgu, Southeastern Nigeria, were determined in the laboratory and their behaviour in terms of changes in the engineering properties on treatment with various percentages of cement (2,4,6,8 and 10) investigated. Results of the study show that liquid limit, plasticity index and Linear Shrinkage values of the treated soil were reduced while the maximum dry density and CBR values were increased. The maximum reduction percentages of 34.61% (56.60 to 37.01%), 72.89% (33.60 to 9.11%) and 46.51% (12.90 to 6.90%) in liquid limit, plasticity index and Linear Shrinkage, respectively; and maximum percent increase of 7.59% (1.58 to 1.70mg/m 3 , on maximum dry density), 236.36% (11 to 37%, on unsoaked CBR) and 800.00% (3 to 27%, on soaked CBR), were obtained on treatment of the soil with 8% cement by weight. The swelling indicators/parameters of the studied soil are liquid limit; plasticity index and Linear Shrinkage while the strength characteristics/parameters of the studied soil are maximum dry density and California Bearing Ratio (CBR). Treatment of the soil with cement has thus reduced its swelling potential from high to low and increased the strength significantly Keywords: Subgrade, expansive soils, cement treatment, plasticity characteristics, reduction percentage, strength characteristics, percent increase.
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Engineering Behaviour of Cement-Treated Expansive Subgrade Soils from Awgu, Southeastern Nigeria
Civil and environmental research, 2015Co-Authors: O.c. Okeke, O.i. Imasuen, C O Okogbue, Okechukwu Pius AghameluAbstract:Engineering behaviour of cement-treated expansive soils refers to changes in the engineering properties of the soil in terms of reduction in values of swelling indicators and increase in values of strength characteristics of the soil when it is treated with various percentages of cement. In this study, engineering properties including liquid limit, plasticity index, Linear Shrinkage, maximum dry density/optimum moisture content, and California Bearing Ration (CBR) of expansive subgrade soils from Awgu, Southeastern Nigeria, were determined in the laboratory and their behaviour in terms of changes in the engineering properties on treatment with various percentages of cement (2,4,6,8 and 10) investigated. Results of the study show that liquid limit, plasticity index and Linear Shrinkage values of the treated soil were reduced while the maximum dry density and CBR values were increased. The maximum reduction percentages of 34.61% (56.60 to 37.01%), 72.89% (33.60 to 9.11%) and 46.51% (12.90 to 6.90%) in liquid limit, plasticity index and Linear Shrinkage, respectively; and maximum percent increase of 7.59% (1.58 to 1.70mg/m 3 , on maximum dry density), 236.36% (11 to 37%, on unsoaked CBR) and 800.00% (3 to 27%, on soaked CBR), were obtained on treatment of the soil with 8% cement by weight. The swelling indicators/parameters of the studied soil are liquid limit; plasticity index and Linear Shrinkage while the strength characteristics/parameters of the studied soil are maximum dry density and California Bearing Ratio (CBR). Treatment of the soil with cement has thus reduced its swelling potential from high to low and increased the strength significantly Keywords: Subgrade, expansive soils, cement treatment, plasticity characteristics, reduction percentage, strength characteristics, percent increase.
Yoni Moses - One of the best experts on this subject based on the ideXlab platform.
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Locally Computable UOWHF with Linear Shrinkage
Journal of Cryptology, 2017Co-Authors: Benny Applebaum, Yoni MosesAbstract:We study the problem of constructing locally computable universal one-way hash functions (UOWHFs) $$\mathcal {H}:\{0,1\}^n \rightarrow \{0,1\}^m$$ H : { 0 , 1 } n → { 0 , 1 } m . A construction with constant output locality , where every bit of the output depends only on a constant number of bits of the input, was established by Applebaum et al. (SIAM J Comput 36(4):845–888, 2006 ). However, this construction suffers from two limitations: (1) it can only achieve a subLinear Shrinkage of $$n-m=n^{1-\epsilon }$$ n - m = n 1 - ϵ and (2) it has a super-constant input locality , i.e., some inputs influence a large super-constant number of outputs. This leaves open the question of realizing UOWHFs with constant output locality and Linear Shrinkage of $$n-m= \epsilon n$$ n - m = ϵ n , or UOWHFs with constant input locality and minimal Shrinkage of $$n-m=1$$ n - m = 1 . We settle both questions simultaneously by providing the first construction of UOWHFs with Linear Shrinkage, constant input locality and constant output locality. Our construction is based on the one-wayness of “random” local functions—a variant of an assumption made by Goldreich (Studies in Complexity and Cryptography, 76–87, 2011 ; ECCC 2010). Using a transformation of Ishai et al. (STOC, 2008 ), our UOWHFs give rise to a digital signature scheme with a minimal additive complexity overhead: signing n -bit messages with security parameter $$\kappa $$ κ takes only $$O(n+\kappa )$$ O ( n + κ ) time instead of $$O(n\kappa )$$ O ( n κ ) as in typical constructions. Previously, such signatures were only known to exist under an exponential hardness assumption. As an additional contribution, we obtain new locally computable hardness amplification procedures for UOWHFs that preserve Linear Shrinkage.
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locally computable uowhf with Linear Shrinkage
Theory and Application of Cryptographic Techniques, 2013Co-Authors: Benny Applebaum, Yoni MosesAbstract:We study the problem of constructing locally computable Universal One-Way Hash Functions (UOWHFs) \(\mathcal{H}:\{0,1\}^n \rightarrow \{0,1\}^m\). A construction with constant output locality, where every bit of the output depends only on a constant number of bits of the input, was established by [Applebaum, Ishai, and Kushilevitz, SICOMP 2006]. However, this construction suffers from two limitations: (1) It can only achieve a sub-Linear Shrinkage of n − m = n 1 − e ; and (2) It has a super-constant input locality, i.e., some inputs influence a large super-constant number of outputs. This leaves open the question of realizing UOWHFs with constant output locality and Linear Shrinkage of n − m = en, or UOWHFs with constant input locality and minimal Shrinkage of n − m = 1.
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EUROCRYPT - Locally Computable UOWHF with Linear Shrinkage
Advances in Cryptology – EUROCRYPT 2013, 2013Co-Authors: Benny Applebaum, Yoni MosesAbstract:We study the problem of constructing locally computable Universal One-Way Hash Functions (UOWHFs) \(\mathcal{H}:\{0,1\}^n \rightarrow \{0,1\}^m\). A construction with constant output locality, where every bit of the output depends only on a constant number of bits of the input, was established by [Applebaum, Ishai, and Kushilevitz, SICOMP 2006]. However, this construction suffers from two limitations: (1) It can only achieve a sub-Linear Shrinkage of n − m = n 1 − e ; and (2) It has a super-constant input locality, i.e., some inputs influence a large super-constant number of outputs. This leaves open the question of realizing UOWHFs with constant output locality and Linear Shrinkage of n − m = en, or UOWHFs with constant input locality and minimal Shrinkage of n − m = 1.
Liangfa Hu - One of the best experts on this subject based on the ideXlab platform.
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effect of sintering temperature on compressive strength of porous yttria stabilized zirconia ceramics
Ceramics International, 2010Co-Authors: Liangfa Hu, Changan WangAbstract:Abstract Porous yttria-stabilized zirconia (YSZ) ceramics were fabricated by tert-butyl alcohol (TBA)-based gel-casting method for potential applications in heat-insulation materials. The effect of sintering temperature on compressive strength of porous YSZ ceramics was investigated on the basis of measurements Linear Shrinkage, porosity and pore size. As the sintering temperature increased from 1350 to 1550 °C, a decrease of porosity from 77 to 65%, a decrease of average pore size from and an increase of Linear Shrinkage from 15.4 to 31.8% were observed. The compressive strength increased remarkably from 3 to 27 MPa with increasing sintering temperature from 1350 to 1550 °C, which was related to the corresponding change of Linear Shrinkage, porosity, pore size and microstructure. A remarkable decrease of compressive strength with increasing porosity was observed. The compressive strength decreased also with increasing pore size.
K Janghorban - One of the best experts on this subject based on the ideXlab platform.
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EFFECT OF BI2O3 DOPING ON THE CURIE TEMPERATURE, Q FACTOR AND Linear Shrinkage OF MN-ZN FERRITES
2007Co-Authors: H Shokrollahi, K JanghorbanAbstract:Bi2O3 was added to the Mn-Zn ferrite (52 mol % Fe2O3, 34 mol% MnO, 14 mol% ZnO) in the amounts of 0.03, 0.08, 0.2, 1 and 5 wt%. Q factor, Curie temperature and Linear Shrinkage were investigated. Several sintering conditions were practiced. The optimum sintering condition (1200 °C for 1 hour) was determined based on the maximum value of the Q factor of undoped ferrite. The net magnetic moment, Curie point and Shrinkage behavior of the material were influenced by Bi2O3. Results showed that in small additions of Bi2O3 (0.03 wt %), the Q factor was the maximum, and with increasing Bi2O3, the Linear Shrinkage decreased. The Curie temperature changed in two stages; it increased in the first where Bi2O3 was below 1 wt%, and then decreased above this value. Keywords– Mn-Zn ferrite, Bi2O3, Curie temperature, Q factor, Linear Shrinkage
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EFFECT OF MOO3 ADDITION ON THE Q FACTOR, CURIE TEMPERATURE AND Linear Shrinkage OF MN-ZN FERRITES
2006Co-Authors: H Shokrollahi, K JanghorbanAbstract:In this work MoO3 was added to the Mn-Zn ferrite with the basic composition of (52mol% of Fe2O3, 34mol% of MnO, 14mol% of ZnO) at concentrations of 0.08, 0.5, 1 and 5 wt%. The optimum sintering condition was determined based on maximum Q factor values. The microstructure of the sintered samples was studied using SEM. The magnetic properties were characterized by determining Q factor and Curie temperature. Results showed that the addition of MoO3 increased Curie temperature and noticeably decreased Linear Shrinkage. The Q factor was maximized at a concentration of 0.5 wt% MoO3 making this value the best. Keywords– Soft magnetic materials, Mn-Zn ferrite, Curie temperature, Q factor, Linear Shrinkage