倒立摆系统的神经网络控制研究

神经网络具有突出自适应性和鲁棒性。本文针对一种复杂的倒立摆系统,采用BP神经网络取代传统控制方法 ,实现倒立摆装置的平稳控制。仿真实验结果表明,只要数据信息量及神经网络隐层神经元个数适当,即可到达较好的控制效果。该文描述了实现过程及方法,可达到对倒立摆装置更平稳的控制。     

倒立摆的串级控制系统设计

在保证倒立摆摆杆不倒的条件下,使小车位置可控,应用串级控制设计方法 ,内环按照典I系统外环按照典II系统设计原则设计,仿真结果验证了控制系统具有良好的性能。     

基于广义通用模型控制器的倒立摆串级控制系统设计

在保证倒立摆摆杆不倒的条件下,使小车位置可控,应用串级控制设计方法 ,首先推导出相应的模型,应用广义通用模型控制器的设计方法对于内环及外环进行设计,将被控对象的模型嵌入到控制器中,应用主导极点的思想对于控制器参数进行选择,仿真结果验证了控制系统具有良好的性能。     

MEMS谐振器的滑模变结构控制

微电机系统(MEMS)是由多种学科交叉融合的跨学科研究领域。本文利用滑模变结构控制法对MEMS谐振器混沌运动进行了控制。最后用数值模拟验证了所选控制器的有效性。     

猪圆环病毒II型结构蛋白的二级结构及其B细胞抗原表位预测

本研究以猪圆环病毒(porcine circovirus,PCV)II型的基因组序列为材料,采用Garnier-Robson方法、Chou-Farplus方法和Karplus-Schulz方法预测了其结构蛋白的二级结构,用Kyte-Doolittle方法对结构蛋白的亲水性进行了分析,用Emini方法预测了结构蛋白的表面可能性,以Jameson-Wolf方法预测了蛋白的抗原指数。然后综合评价了PCV-2型结构蛋白的B细胞抗原表位。结果表明,PCV-2结构蛋白形成α螺旋结构的能力较差,但是该蛋白含有较多的β折叠和转角结构,因而该蛋白具有丰富的二级结构。分析结果还表明结构蛋白具有多处抗原指数较高的区段,其中羧基端含有潜在的B细胞优势抗原表位,因此其在免疫学中的地位也应当引起重视。本研究将为猪圆环病毒的反向疫苗学的研究提供一定的理论依据。     

猪圆环病毒Ⅱ型结构蛋白的二级结构及其B细胞抗原表位预测

本研究以猪圆环病毒(porcine circovirus,PCV)Ⅱ型的基因组序列为材料,采用Gamier-Robson方法、Chou-Farplus 方法和Karplus-Schulz方法预测了其结构蛋白的二级结构,用Kyte-Doolittle方法对结构蛋白的亲水性进行了分析,用Emini方法预测了结构蛋白的表面可能性,以Jameson-Wolf方法预测了蛋白的抗原指数.然后综合评价了PCV-2型结构蛋白的B细胞抗原表位.结果表明,PCV-2结构蛋白形成α螺旋结构的能力较差,但是该蛋白含有较多的β折叠和转角结构,因而该蛋白具有丰富的二级结构.分析结果还表明结构蛋白具有多处抗原指数较高的区段,其中羧基端含有潜在的B细胞优势抗原表位,因此其在免疫学中的地位也应当引起重视.本研究将为猪圆环病毒的反向疫苗学的研究提供一定的理论依据.     

探究10kV变配电室的施工控制

变配电室工序复杂,设备安装及调试时间紧迫。本文结合工程实例,分析了10kV变配电室内施工的具体特点,并针对变配电室内施工控制比较复杂,并提出了便于分解施工中安全、进度、质量控制的控制模型及其补充,利用控制模型分解了安全、进度、质量控制的内容,从而取得了良好的控制效果。     

牛乳、驴乳乳清蛋白二级结构及其功能对比研究

采用傅里叶变换红外光谱法对驴初乳、驴常乳、牛初乳和牛常乳的乳清蛋白二级结构进行分析,再通过基因本体论功能注释和KEGG(Kyoto Encyclopedia of Genes and Genomes)代谢通路分析其功能及差异.结果表明:驴乳和牛乳乳清蛋白的二级结构存在差异;随着泌乳期的延长,二者的乳清蛋白二级结构含量也...     

Sensitivity of double microcentrifugation for the research of trypanosomes

The double microcentrifugation technique, described by KRATZER and ONDIEK (1989) for the parasitological diagnosis of trypanosomes, has been tested both in the laboratory and in the field. The limits of detection obtained here were not as low as those described in the original experiment, but the sensitivity of this technique for the detection of Trypanosoma brucei, T. congolense and T. vivax was better than the phase contrast buffy coat method. This technique, which is easy to apply in the field, is highly recommended, especially for epidemiological surveys. A protocol and a list of equipment are included.     

一种轻量化高强度仪控设备机械结构的设计与仿真

本文设计了一款用于搭载仪控设备的机柜。通过在材料选取,框架结构,联接设计等方面着手,使得机柜在满足低成本,轻量化的前提下实现了较高的结构强度。机柜强度还通过有限元仿真软件进行了仿真验证,验证其性能满足标准要求。     

基于GUI/Simulink的起落架收放控制逻辑联合建模与仿真研究

以某型飞机起落架收放控制系统收放控制逻辑为对象,建立Matlab GUI(graphic user interface)和Simulink联合仿真模型,与单独采用Simulink建模相比,联合仿真模型具有显示直观、便于测试分析等优点。仿真结果表明,联合仿真模型能够实现不同测试方案的快速测试、仿真结果对比分析及记录,能够完成起落架收放控制逻辑的全数字仿真需求,为起落架收放控制逻辑的验证分析提供有力的支持。     

FPGA在多机功率平衡的变频控制系统中的应用

针对多台拖动系统共同拖动一台负载的时出现功率不平衡的问题,本文介绍了一种带有多机功率平衡功能的变频控制系统。并详细介绍了FPGA在该系统中的应用。     

新型试验电源直流降压斩波系统的PID控制仿真研究

为解决小机车新型试验电源直流降压斩波电路中存在的输出电压不稳定、IGBT开关损耗大、系统非线性干扰强等问题,斩波电路部分采用PID控制策略进行PWM脉波输出控制IGBT开关动作和直流降压斩波。本文就PID控制直流降压斩波原理进行了阐述,并采用MATLAB中的simulink进行了电路部分的仿真,分析仿真结果表明,PID控制下的直流降压斩波能够达到预期的目标,更易于整个系统的控制和运行。     

Investigations with enzyme-linked immunosorbent assays for Trichinella spiralis and Toxoplasma gondii in the Dutch 'Integrated Quality Control for finishing pigs' research project.

In the framework of the Dutch field trial 'Integrated Quality Control (IQC) for finishing pigs' ELISA (screening) techniques were used to detect animals seropositive for Toxoplasma gondii and/or Trichinella spiralis. The aim was to determine whether farms which consistently delivered seropositive pigs could be detected and monitored (defined as 'problem farms'). The investigation involved 120 farms and three slaughterhouses, and a total of 23,348 serum samples were examined. In addition, all pigs were also screened for the presence of Trichinella spiralis with the digestion method (pooled samples). The prevalence of seropositivity for Trichinella spiralis and Toxoplasma gondii was 0.3% and 2.1% respectively. Parasitological examinations concerning T. spiralis were negative. Considering the characteristics of the used methodology, the conclusion was drawn that there were no parasitological or serological indications for T. spiralis infections, and that with respect to T. gondii the infection rate seemed to be equally low for all farms involved. In addition, a longitudinal pilot study during a whole finishing period was undertaken at two finishing farms. Animals seropositive for Toxoplasma gondii were found from the earliest days of the finishing period. Housing and management may (still) play an important role in the prevention of contact with this parasite.     

多年生紫花苜蓿饲喂奶牛试验研究

紫花苜蓿营养丰富,是奶牛饲草的最佳粗饲料,不论青饲还是调制成干草,适口性都很好,用于饲喂奶牛可显著提高奶牛产奶量,增加奶农户经济收入。     

Joint research on the precise determination of the energy and protein requirements of fattening pigs. 10. Comparative evaluation of the research for the precise determination of the energy and protein requirements of fattening pigs

Institutes from 5 CMEA countries took part in complementary joint investigations in order to ascertain the variance in energy and protein requirement and parameters of nutrient and energy metabolism with such fattening pigs as test animals as characterise the prospective breeding development in each of the countries and in order to establish the bases for the critical revision of the norms of energy and protein requirement for fattening pigs and, if necessary, their more precise determination. The most important conclusion drawn from the comparative assessment of the results presented in 9 articles is that due to wide variations in the energy and protein requirement values between the individual investigators as well as within the institutions themselves, norms of energy and protein requirement for fattening can only be adopted between countries when adequate investigations under the specific conditions of the individual countries justify this.     

边境地区动物疫病联防联控长效机制探索与应用

"十三五"以来,黑河市通过制定实施重大动物疫病防控相关法律法规、制度和措施,完善指挥体系架构,建立防范高风险疫病跨境传入的人防物防体系、域内域外联防联控合作交流机制、风险评估机制、联合执法机制,大幅提升了重大动物疫病防治指挥部成员单位专业队伍的业务知识和技能水平,有力打击了违法违规行为,降低了疫病发生风险,构筑了"外防...     

基于DEM-CFD耦合的锤片式粉碎机筛分效率模拟研究

为提高新型锤片式饲料粉碎机的筛分效率,现利用EDEM-Fluent耦合法对该机进行数值模拟.先对EDEM和Fluent耦合计算筛分效率的准确性进行试验验证,再分别模拟不同喂料速率、不同喂料量、不同回料管直径下粉碎机的筛分效率,分析粉碎过程中物料在该机内部的分布规律以及3种影响因素分别对应的筛分效率最大值.结果 表明,物...