blend crossover ga
96795088
Hydrocarbon blend membranes with suppressed chemical crossover for redox flow batteries
A hydrocarbon blend membrane consisting of an acidic polymer (sulfonated poly (ether ether ketone) SPEEK) and a basic polymer (polysulfone 2 amide benzimidazole, PSf ABIm) has been prepared and assessed in vanadium redox flow batteries (VRBs) The vanadium ion (VO)2+ permeability through the blend membrane is about 50 times lower than that of Nafion 117 and 4 times lower than that of the plain SPEEK. The Coulombic efficiency and energy efficiency of the single cell with the blend membrane are higher than those with Nafion and plain SPEEK membranes. The blend membrane also shows better chemical stability than plain SPEEK. The results demonstrate that blend membranes of this type are promising for VRBs.
Xinsheng Zhao Yongzhu Fu Wei Li Arumugam Manthiram
199582079
Evolution of Subjective Utilities by GA with BLX a
Utility based Q learning, which uses subjective utilities as rewards of Q learning, has been proposed and the utilities that derive mutual cooperation in a Prisoner's Dilemma game have been successfully evolved by real coded genetic algorithm (RCGA) However, in that work, the genes were simply exchanged in the evolution process like a bit string GA and the search space was not so wide as a result. This work investigates the evolution of the subjective utilities by RCGA with blend crossover (BLX a) that has a powerful search ability by generating various chromosomes.
Naoya Okada
122291273
Multi modal distribution crossover method based on two crossing segments bounded by selected parents applied to multi objective design optimization
This paper discusses airfoil design optimization using a genetic algorithm (GA) with multi modal distribution crossover (MMDX) The proposed crossover method creates four segments from four parents, of which two segments are bounded by selected parents and two segments are bounded by one parent and another segment. After these segments are defined, four offsprings are generated. This study applied the proposed optimization to a real world, multi objective airfoil design problem using class shape function transformation parameterization, which is an airfoil representation that uses polynomial function, to investigate the effectiveness of this algorithm. The results are compared with the results of the blend crossover (BLX) and unimodal normal distribution crossover (UNDX) algorithms. The objective of these airfoil design problems is to successfully find the optimal design. The outcome of using this algorithm is superior to that of the BLX and UNDX crossover methods because the proposed method can maintain higher diversity than the BLX and UNDX methods. This advantage is desirable for real world problems.
Atthaphon Ariyarit Masahiro Kanazaki
4092939
Study on Different Crossover Mechanisms of Genetic Algorithm for Test Interval Optimization for Nuclear Power Plants
Surveillance tests are performed periodically on standby systems of a Nuclear Power Plant (NPP) as they improve the systems' availability on demand. High availability of safety critical systems is very essential to NPP safety, hence, careful analysis is required to schedule the surveillance activities for such systems in a cost effective way without compromising the plant safety. This forms an optimization problem wherein, two different cases can be formulated for deciding the value of Surveillance Test Interval. In one case, cost is the objective function to be minimized while unavailability is constrained to be at a given level and in another case, unavailability is minimized for a given cost level. Here, optimization is done using Genetic Algorithm (GA) and real encoding has been employed as it caters well to the requirements of this problem. A detailed procedure for GA formulation is described in this paper. Two different crossover methods, arithmetical crossover and blend crossover are explored and compared in this study to arrive at the most suitable crossover method for such type of problems.
Molly Mehra M L Jayalal A John Arul S Rajeswari K K Kuriakose S A V Satya Murty
15840085
Effects of culinary spices and psychological stress on postprandial lipemia and lipase activity: results of a randomized crossover study and in vitro experiments
BackgroundData suggest that culinary spices are a potent, low calorie modality for improving physiological responses to high fat meals. In a pilot study (N 6 healthy adults) we showed that a meal containing a high antioxidant spice blend attenuated postprandial lipemia by 30% compared to a low spice meal. Our goal was to confirm this effect in a larger sample and to consider the influence of acute psychological stress on fat metabolism. Further, we used in vitro methods to evaluate the inhibitory effect of spices on digestive enzymes.MethodsIn a 2 x 2, randomized, 4 period crossover design, we compared the effects of 14.5 g spices (black pepper, cinnamon, cloves, garlic, ginger, oregano, paprika, rosemary, and turmeric) vs. placebo incorporated into a high fat meal (1000 kcal, 45 g fat) followed by psychological stress (Trier Social Stress Test) vs. rest on postprandial metabolism in 20 healthy but overweight adults. Blood was sampled at baseline and at 105, 140, 180, and 210 minutes for analysis of triglycerides, glucose, and insulin. Additional in vitro analyses examined the effect of the spice blend and constituent spices on the activity of pancreatic lipase (PL) and secreted phospholipase A2 (PLA2) Mixed models were used to model the effects of spices and stress (SAS v9.3).ResultsSerum triglycerides, glucose and insulin were elevated following the meal (p 0.01) Spices reduced post meal triglycerides by 31% when the meal was followed by the rest condition (p 0.048) but this effect was not present during stress. There was no effect of the spice blend on glucose or insulin; however, acute stress significantly increased both of these measures (p 0.01; mean increase of 47% and 19% respectively) The spice blend and several of the individual spices dose dependently inhibited PL and PLA2 activity in vitro.ConclusionsInclusion of spices may attenuate postprandial lipemia via inhibition of PL and PLA2. However, the impact of psychological stress negates any influence of the spice blend on triglycerides, and further, increases blood glucose and insulin.Trial registrationClinicalTrials.gov as NCT00954902.
Journal of Translational Medicine
Cindy E McCrea Sheila G West Penny M Kris-Etherton Joshua D Lambert Trent L Gaugler Danette L Teeter Katherine Ann Sauder Yeyi Gu Shannon L Glisan Ann C Skulas-Ray
94949448
Acid base blend membranes consisting of sulfonated poly(ether ether ketone) and 5 amino benzotriazole tethered polysulfone for DMFC
Abstract Low cost, acid base blend membranes have been synthesized by blending sulfonated poly(ether ether ketone) (SPEEK) (an acid polymer) and various amounts of polysulfone tethered with 5 amino benzotriazole (a basic polymer) The blend membranes have been characterized by ion exchange capacity (IEC) liquid uptake, proton conductivity, methanol crossover, and fuel cell performance measurements. The blend membranes exhibit superior performance in direct methanol fuel cells (DMFC) compared to plain SPEEK and Nafion 115 membranes due to enhanced proton conductivity and much suppressed methanol crossover while preserving good swelling stability. The maximum power density of the blend membrane is two times higher than that of Nafion 115 membrane at 80 degC with 1 M methanol feed. Additionally, the effects of the size, pKa, and the number of nitrogen atoms of the tethered heterocycle groups on the properties of the blend membranes have also been investigated by comparing the properties of the blend membranes consisting of SPEEK and different basic polymers.
Wen Li Arumugam Manthiram Michael D Guiver
98516672
High performance direct methanol fuel cells based on acid base blend membranes containing benzotriazole
Abstract Novel acid base blend membranes consisting of acidic sulfophenylated poly(ether ether ketone ketone) (Ph SPEEKK) and various amounts of basic polysulfone tethered with 5 amino benzotriazole (PSf BTraz) have been prepared and characterized. The blend membranes show higher proton conductivity and lower liquid uptake and dimensional swelling compared to plain Ph SPEEKK and sulfonated poly(ether ether ketone) (SPEEK) membranes. The Ph SPEEKK/PSf BTraz blend membranes with optimized basic polymer contents exhibit lower methanol crossover and higher performance with improved stability in direct methanol fuel cells (DMFC) at various methanol concentrations (1 10 M) than plain Ph SPEEK and Nafion 115 membranes.
Wen Yi Li Arumugam Manthiram Michael D Guiver Baijun Liu
24716700
Wetting in a phase separating polymer blend film: quench depth dependence
We have used 3He nuclear reaction analysis to measure the growth of the wetting layer as a function of immiscibility (quench depth) in blends of deuterated polystyrene and poly(alpha methylstyrene) undergoing surface directed spinodal decomposition. We are able to identify three different laws for the surface layer growth with time t. For the deepest quenches, the forces driving phase separation dominate (high thermal noise) and the surface layer grows with a t(1/3) coarsening behavior. For shallower quenches, a logarithmic behavior is observed, indicative of a low noise system. The crossover from logarithmic growth to t(1/3) behavior is close to where a wetting transition should occur. We also discuss the possibility of a "plating transition" extending complete wetting to deeper quenches by comparing the surface field with thermal noise. For the shallowest quench, a critical blend exhibits a t(1/2) behavior. We believe this surface layer growth is driven by the curvature of domains at the surface and shows how the wetting layer forms in the absence of thermal noise. This suggestion is reinforced by a slower growth at later times, indicating that the surface domains have coalesced. Atomic force microscopy measurements in each of the different regimes further support the above. The surface in the region of t(1/3) growth is initially somewhat rougher than that in the regime of logarithmic growth, indicating the existence of droplets at the surface.
Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics
95378406
Blend membranes consisting of sulfonated poly(ether ether ketone) and 1H perimidine tethered polysulfone for direct methanol fuel cells
Blend membranes consisting of sulfonated poly(ether ether ketone) (SPEEK, an acidic polymer) and various amounts of 1H perimidine tethered polysulfone (a basic polymer) have been prepared and characterized. The blend membranes show increased proton conductivity and decreased ion exchange capacity and liquid uptake in water and methanol/water solutions com pared to plain SPEEK. The blend membranes also exhibit better electrochemical performance and lower methanol crossover in direct methanol fuel cells compared to plain SPEEK and Nafion 115 membranes due to an enhancement in proton conductivity through acid base interactions and an insertion of the 1H perimidine groups into the ionic clusters of SPEEK.
Wen Li Arumugam Manthiram Michael D Guiver
93725432
Electronic and Structural Properties of Zincblende B x Ga 1 x N
We present structural and electronic properties of the cubic structure for different concentrations x of ternary alloy BxGa1 xN. The computational method is based on the full potential linearised augmented plane wave method (FP LAPW) The exchange and correlation energy is described in the local density approximation (LDA) and generalized gradient approximation (GGA) We have investigated the effect of composition on the ground state properties, lattice parameters, bulk modulus, pressure derivative and band gap of the zinc blend BN and GaN. The results obtained are in a good agreement with experimental and theoretical values concerning the variation of the gaps and crossover direct, indirect band gap and the bowing parameter. A reasonable agreement is found from the comparison of our results with other theoretical calculations.
Abdelhadi Lachebi H Abid