基于全局优化改进混沌粒子群遗传算法的物料平衡数据校正

结合遗传算法（GA）和粒子群算法（PSO）的优点以及混沌运动的特性,提出了加入混沌扰动的混沌粒子群遗传算法（DCPSO-GA）,并使用5个高维非线性测试函数考察全局优化混合算法的性能。DCPSO-GA解决了在寻优搜索时出现的停滞现象,扩大了全局优化的搜索空间,丰富了粒子的多样性,且不需要函数梯度信息。测试结果证明,针对本文的5个测试函数DCPSO-GA能找到全局最优解,其收敛速度很快,大大减少了计算量。而且,经过与其他相关算法比较可知,当总的目标函数调用次数较接近或更少时,改进算法不论在计算精度还是收敛速度上,均有很大的提高。并将DCPSO-GA算法应用到重油裂解参数估计和预测中,测试结果证明,其提高了参数估计和预测的准确性,降低了误差,能有效找到全局最优解,收敛速度快,大大减少计算量。     

混沌遗传算法估计反应动力学参数

为了准确地估计反应动力学参数 ,提出一种混沌遗传算法 (chaosgeneticalgorithm ,CGA) ,它基于混沌变量的遗传操作 ,将使子代个体均匀地分布于定义空间 ,从而可避免早熟 ,以较大的概率实现全局最优搜索 .与传统的遗传算法相比较 ,CGA的在线和离线性能都有较大的改进 .将CGA应用于 2 -氯苯酚在超临界水中氧化反应动力学参数的估算 ,获得了满意的结果     

混沌粒子群算法及其在生化过程动态优化中的应用

化工过程的动态优化,大多较为复杂,有相当的难度.新近发展的粒子群优化算法,基于群智能机理,适于求解连续问题,但它不具备遍历特性,影响了全局搜索能力.本文拟引入混沌机制,以混沌变量的遍历性改进粒子群算法,使其更全面地获取目标函数的有用信息,并反映到逐代更新的个体极值和群体极值中,可更有效地带领粒子群移向最优解,提高了全局搜优效率.由此构建为混沌粒子群算法,经多个性能测试,表明其搜索能力优于经典粒子群算法,引入混沌机制是有效的.将其用于Park-Ramirez生物反应器补料流率的动态优化,也取得了满意的效果.     

基于火电厂发电量预测的多目标配煤方法

分析上海某火电厂实际生产数据,建立基于Elman神经网络的火电厂发电量滚动预测模型,根据发电量历史数据本身的动态特性预测未来发电量数据,预测精度较其他算法有明显提高。将火电厂年发电量预测数据与年耗煤量数据相结合,计算出混煤平均发热量,将其作为配煤影响指标,与通过设计煤种参数构建的控煤约束指标共同构成控煤目标函数,与经济目标函数建立多目标配煤模型,采用改进交叉、变异概率的非支配排序遗传算法(non-dominated sorting genetic algorithm, NSGA-Ⅱ)进行模型求解,使其更符合配煤特点。提出一种基于火电厂发电量预测的多目标配煤方法,结果表明:该配煤方法不仅充分考虑耗煤量和煤质特性约束情况,还将整个模型应用于实际配煤过程,提高了配煤结果的可靠性、实用性和灵活性,并使电厂获得了较好的经济效益。     

使用博弈差分算法的电站锅炉高效低污染燃烧均衡优化

提高电站锅炉热效率,降低NO_x等污染物的排放量是电站节能减排必须解决的问题。经过采用经量子遗传算法(QGA)优化参数后的最小二乘支持向量机(LSSVM-QGA)建立燃烧优化模型,预测的锅炉热效率和NO_x排放量的平均相对误差分别达到了0.054%和1.229%,其预测精度及泛化能力均较优,有更强的适用性能。在此模型基础上,提出一种采用自适应缩放因子与交叉因子和共享函数机制的差分进化算法(DE),通过其演化博弈论中的NASH均衡,实现锅炉燃烧的多目标优化,结果表明,基于NASH均衡的优化方法可以得到操作变量的最优解集,能够更好地改善运行工况,最终可以实现削峰填谷,使电站锅炉保持一个稳定均衡的燃烧状态。     

应用经遗传算法优化的BP神经网络预测催化裂化装置焦炭产率

焦炭是催化裂化装置的主要副产物,准确预测催化裂化焦炭产率对提高装置的操作平稳度和经济效益具有重要意义。人工神经网络(ANN)具有强大的自学习和自适应能力,在非线性预测方面具有明显的优势。本研究将遗传算法(GA)与BP神经网络相结合,基于某炼厂催化裂化装置的生产数据,分别从原料、催化剂和操作条件3个方面选取28个关键影响参数建立了催化裂化焦炭产率预测模型,分别将BP神经网络和经遗传算法优化的BP神经网络(GA-BP)的预测结果与工业数据进行对比。结果表明,经遗传算法优化的预测模型无论在预测结果的准确性还是稳定性方面效果更好。最后,本研究还通过考察原料残炭、反应温度等单一关键参数对焦炭产率的影响,进一步证明了经遗传算法优化的BP神经网络预测模型的准确性。     

变尺度混沌遗传算法及其在冷扎参数化中的应用

针对标准遗传算法存在的收敛速度慢，易陷入局部极小等问题，提出智能化新方法，基于变尺度混沌优化策略的混沌遗传算法，对经过一次遗传操作的群体进行混沌搜索寻伏，引导种群快速进化，并将其成为应用于冷轧参数的优化计算中。     

模糊PFC及应用研究

温度控制系统的传递函数不是固定不变的,常规控制方法很难满足控制要求。预测函数控制属于预测控制的一种,当模型参数与实际系统参数相差较大时,控制效果将受到影响。根据影响系统参数的主要因素,离线辨识出系统传递函数,结合模糊控制理论,提出模糊PFC控制理论,实时地调整预测模型,提高预测函数控制的自适应能力。     

基于遗传算法变量选择的子空间辨识方法研究

针对污水处理过程中重要水质参数BOD_5(5天生化需氧量)和COD(化学需氧量)的难以实时在线测量问题,提出了基于遗传算法变量选择的子空间辨识软测量建模方法。先利用遗传算法选出与目标变量密切相关的辅助变量,再结合子空间算法建立目标函数的预测模型。基于加州大学的UCI数据库进行仿真实验,结果表明,结合变量选择后的模型比仅使用子空间建模的模型,其预测精度得到了提高,进一步验证了文中方法的有效性。     

基于结构风险最小化原则的径向基函数网络

通过分析径向基函数网络与支持向量机之间的关系,将结构风险最小化原则应用于径向基函数网络学习中,与传统的基于经验风险最小化原则的径向基函数网络相比,它充分保证了模型的泛化能力,能够弥补学习方法本身的缺陷.最后,将该算法应用于非线性时间序列预测,并与传统的径向基函数网络预测结果进行了比较,实验结果表明本算法提高了径向基函数网络的泛化能力.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料，介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比，介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序，对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。     

Inorganic/organic nanocomposite coatings: The next step in coating performance

Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.