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供暖系统最佳启动控制的重点在于准确预测预热时间,获取供暖系统的准确预热时间,并以其控制供暖系统的启动,有助于整个供暖系统能耗最小化.针对具有间歇供暖系统供暖的建筑物,分析其内部温度在外界环境和热源影响下的变化过程和规律,从热力学角度建立了间歇供暖预热过程的数学模型.基于该模型,在间歇供暖的启动控制中引入了自校正控制,并进行了仿真和实验.结果表明,将自校正控制用于供暖系统的启动控制效果较好,能够节约能源. 相似文献
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粒子群算法是一种基于群智能的全局寻优方法,方法简单易于实现,寻优效果好.本文设计了一种基于粒子群算法的自整定PID控制器.它可以根据系统参数的变化实现在线的PID参数优化.仿真结果证明其性能良好. 相似文献
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Yamshi Arif Priyanka Singh Andrzej Bajguz Shamsul Hayat 《International journal of molecular sciences》2022,23(15)
Phytoecdysteroids (PEs) are naturally occurring polyhydroxylated compounds with a structure similar to that of insect molting hormone and the plant hormone brassinosteroids. PEs have a four-ringed skeleton composed of 27, 28, 29, or 30 carbon atoms (derived from plant sterols). The carbon skeleton of ecdysteroid is known as cyclopentanoperhydrophenanthrene and has a β-sidechain on C-17. Plants produce PEs via the mevalonate pathway with the help of the precursor acetyl-CoA. PEs are found in algae, fungi, ferns, gymnosperms, and angiosperms; more than 500 different PEs are found in over 100 terrestrial plants. 20-hydroxyecdysone is the most common PE. PEs exhibit versatile biological roles in plants, invertebrates, and mammals. These compounds contribute to mitigating biotic and abiotic stresses. In plants, PEs play a potent role in enhancing tolerance against insects and nematodes via their allelochemical activity, which increases plant biological and metabolic responses. PEs promote enzymatic and non-enzymatic antioxidant defense systems, which decrease reactive oxygen species in the form of superoxide radicals and hydroxyl radicals and reduce malondialdehyde content. PEs also induce protein biosynthesis and modulate carbohydrate and lipid synthesis. In humans, PEs display biological, pharmacological, and medicinal properties, such as anti-diabetic, antioxidant, anti-microbial, hepatoprotective, hypoglycemic, anti-cancer, anti-inflammatory, antidepressant, and tissue differentiation activity. 相似文献
100.
Hiroyuki Fudou Takamu Genji Seiya Abe Takashi Hashimoto 《Electrical Engineering in Japan》2000,130(1):76-87
Transformers with on‐load tap changer and step voltage regulators are most often used for regulating the distribution network voltage. Their use, however, creates certain problems, namely, the voltage control is in discrete steps and the response time is not satisfactory enough. In addition, the power factor (p.f.) compensation relies on capacitors installed by electricity users which creates additional problems manifesting themselves in unexpected overvoltages during light load and increase of power losses. To solve these problems, the authors have proposed a new voltage and p.f. control system for distribution networks based on sophisticated power electronics technology. This paper describes our study on the operating theory of inverter‐controlled regulators and thyristor‐controlled reactors, which play important roles in this system, and the results of simulation through which the usefulness of these equipment has been ascertained. © 1999 Scripta Technica, Electr Eng Jpn, 130(1): 76–87, 2000 相似文献