Evolutionary robustness analysis for multi-objective optimization: benchmark problems

This paper presents a new approach to robustness analysis in multi-objective optimization problems aimed at obtaining the most robust Pareto front solutions and distributing the solutions along the most robust regions of the optimal Pareto set. A new set of test problems accounting for the different types of robustness cases is presented in this study. Non-dominated solutions are classified according to their degree of robustness and are distributed along the Pareto front according to specific algorithm parameter values. Verification of the proposed method is carried out using the developed test problems and artificial and real world benchmark test problems present in the literature.     

Fluidized Bed Air Drying: Experimental Study and Model Development

The presented study describes the processes and mechanisms of batch fluidized bed drying. The influencing factors of hot air drying are theoretically and experimentally examined, in order to present the relations between temperature and humidity profiles and all other drying parameters. A physical model is presented to facilitate the calculation of the drying processes under defined conditions. Three succeeding drying stages are therefore modeled. Mass and energy balances including all components taking part in the process are formulated. The model clarities the drying process under the assumption of pure heat transfer mechanisms. It does not contain adaptive parameters and takes into account an inactive bypass fraction of the fluidization and drying medium. The evaluation of the model was successful for two fluidized bed plants with nominal widths of 100 mm and 400 mm. The experiments showed sufficient accuracy and transferability of the model to equipment of application‐oriented dimensions.     

Synthesis and Characterization of Al-MCM-41 and Al-MCM-48 Mesoporous Materials

A novel route in the synthesis of Al-MCM-41 and Al-MCM-48, using tetraethoxysilane (TEOS) and sodium aluminate (NaAlO₂) as Si and Al source has been obtained. The effect of surfactant nature and the synthesis conditions such as surfactant/Si ratio and hydrothermal treatment time on the formed mesostructure regularity has been studied. Different methods of template removal have also been evaluated. The samples were characterized by X-ray diffraction, nitrogen physisorption, FT-IR, and solid-state MAS NMR spectroscopy.     

基于三电平逆变的开关磁阻发电系统的研究

新型开关磁阻发电机具有发电容量大、效率高、起动和发电组合容易等优点,三电平逆变器具有能减少开关损耗和滤波电感损耗并有降低开关应力等特点。利用三电平逆变器转换效率高的优势,结合新型开关磁阻发电机低风速发电特点,降低开关损耗和开关器件电压应力,提高装置可靠性。仿真实验结果表明:用三电平逆变器能够很好的实现开关磁阻发电机的逆变要求。     

Role of primary and secondary protein structure in neurotransmitter receptor activation mechanisms

A proton transfer triggered by a ligand interacting with thereceptor had been suggested as the initial step in the activationof a receptor for the neurotransmitter serotonin (5-hydroxy-tryptamine;5-HT). To evaluate the role of the receptor macromolecule inmodulating the primary molecular event in ligand-mediated activation,the process of proton transfer was analysed in the environmentof a protein model for the 5-HT receptor. In the absence ofa detailed receptor structure, the enzyme actinidin was chosenas the model for the receptor based on criteria obtained fromstructure-activity considerations on the ligands. The firstsimulation of a mechanism for receptor activation was performedon this model using methods of theoretical chemistry to studythe effect of specific structural elements. The premise is thatthe role of the elements of secondary structure of soluble proteins(e.g. actinidin) in determining structure-function relationsin these macromolecules is maintained when these elements arepart of membrane-bound receptor proteins. Results from the calculationsof the effects of the six alpha helices of actinidin on theproton transfer process from the imidazolium side chain of His162 to the thiol side chain of Cys 25 in the protein show thatthe helices contribute in different ways to modulate the energyof proton transfer. The largest helix, Al, opposes the protontransfer through the effect of the helix dipole. The chargedresidues (primary structure) in helix A3 favor the proton transfer,and mask the effect of its helix dipole (secondary structure)which opposes the transfer. The direction of the proton transfersimulated for the activation mechanism is opposite to that assumedin the catalytic process of the thiol protease, and the entireprotein environment opposes the transfer. This supports thespecific role of the ligand in triggering the proton transferas a response to its binding.     

Effect of low-sulfur fuels upon NH3 and N2O emission during operation of commercial three-way catalytic converters

The use of low-sulfur fuel is known to improve the performance of the three-way catalytic converter (TWC). However, in this work we report how low-sulfur operation of commercial TWC also favors formation of N₂O and NH₃ as by products. We found that low-sulfur rich operation above 300 °C increases the production of NH₃, inhibiting the formation of N₂O characteristic of high-sulfur operation. During lean operation, the production of N₂O near the stoichiometric point is not significantly affected by the sulfur level. The large production of N₂O observed during light-off is not affected by SO₂ when the operation is lean, but under rich conditions N₂O is produced up to 575 °C. The increased production of NH₃ and N₂O in TWC as a result of the introduction of low-sulfur gasoline is an area that requires further analysis because of its implication upon public health in large urban settings.     

鄂东南沿江湖区“灌江纳苗”的认知度调查

本文对拟开展＂灌江纳苗＂工作的目标湖区进行实地调查和深度访谈,调查了大冶湖、网湖、海口湖、朱婆湖四个不同通江湖泊受访人群对＂灌江纳苗＂的知晓率和支持率,并采用问卷调查的方式研究了四个目标湖泊养殖鱼类年产量的变化情况以及四湖受访人群对养殖鱼类品种了解程度。结果显示,在目标湖区开展灌江纳苗工作有一定的群众基础,但也存在一定的工作难度;目标湖区的经济鱼类品种在减少,实施灌江纳苗工作已迫在眉睫。     

斜靠式钢管混凝土异形拱桥非线性稳定分析

斜靠式拱桥是在无风撑拱桥基础上发展起来的一种新型拱桥结构型式.针对此类钢管混凝土异形拱桥的特点对其非线性稳定求解机理和方法进行了分析介绍,以一座拟建的大跨径斜靠式拱桥为例,采用通用程序ANSYS建立该桥的空间有限元计算模型,分工况对其成桥状态进行了线弹性、几何非线性和双重非线性稳定分析计算.同时分析了其主要结构参数(矢跨比、斜拱倾角、横撑数量及位置)对非线性稳定性的影响.计算分析发现:斜靠式拱桥的失稳形式一般表现为面外拱肋侧倾失稳;几何非线性对斜靠式拱桥稳定极限承载力影响较小,要准确的分析其稳定极限承载力必须采用双重非线性的分析方法;横向静风和桥上荷载分布对结构稳定有一定影响而对结构变形影响显著;结构稳定性与矢跨比和斜拱倾角增加均成正比,靠近拱脚和L/4处横撑对结构稳定性影响较大.     

离子型磁性液体中纳米微粒间相互作用研究

用磁偶板子硬球模型对磁性液体中磁性纳米微粒间相互作用进行了研究。分析表明,微粒间存在着静电排斥、静磁吸引和VanderWaals吸引三种相互作用,无外场时静磁作用非常微弱,可以忽略,静电排斥力作用距离远,起抗团聚作用,Vander Waals作用距离短,是引起团聚主要原因。为确保磁性液体稳定性,制备的离子型磁性液体体积分数应小于5％。