科创中国

介绍了葠窝水库发电厂旧监控系统,深入地分析了原有监控系统的现状,从设备、功能等方面剖析了其更新改造的必要性,并且从运行、维护、安全可靠及电站与调度通信等方面考虑,该厂必须进行监控系统的更新改造;在此基础上,按照"无人值班,少人值守"的设计总原则,对该电厂的保护监测系统、视频监控系统、大屏幕系统及励磁装置等设备,分别提出了具体改造方案和主要配置设备,并成功地实现了更新改造.

Now the optimization strategies for power distribution are researched widely,and most of them are aiming to the optimal fuel economy and the driving cycle must be preknown.Thus if the actual driving condition deviates from the scheduled driving cycle,the effect of optimal results will be declined greatly.Therefore,the instantaneous optimization strategy carried out on-line is studied in this paper.The power split path and the transmission efficiency are analyzed based on a special power-split scheme and the efficiency models of the power transmitting components are established.The synthetical efficiency optimization model is established for enhancing the transmission efficiency and the fuel economy.The identification of the synthetical efficiency as the optimization objective and the constrain group are discussed emphatically.The optimization is calculated by the adaptive simulated annealing(ASA)algorithm and realized on-line by the radial basis function(RBF)-based similar models.The optimization for power distribution of the hybrid vehicle in an actual driving condition is carried out and the road test results are presented.The test results indicate that the synthetical efficiency optimization method can enhance the transmission efficiency and the fuel economy of the power-split hybrid electric vehicle(HEV)observably.Compared to the rules-based strategy the optimization strategy is optimal and achieves the approximate global optimization solution for the power distribution.The synthetical efficiency optimization solved by ASA algorithm can give attentions to both optimization quality and calculation efficiency,thus it has good application foreground for the power distribution of power-split HEV.

印刷包装生产线是一个工序复杂的动态离散事件系统(DES),采用建模、仿真和优化相结合的研究方法,合理地安排生产系统的资源并提高生产线的生产率.在印刷包装生产系统框架的基础上,采用Petri网建立了系统的赋时PN模型,并将该模型直观地映射为e M-Plant仿真模型.通过该模型的仿真,分析了生产设备的性能和指标参数,运用约束理论(TOC)找到影响该系统生产率的生产瓶颈,提出了生产线的改进方案并验证其可行性,优化了生产过程.

通过对三相异步电机功率因数控制器的工作原理分析,找出双向晶闸管的输出电压与其可控角之间的关系,提出了将功率因数控制器对晶闸管控制角控制计算转换为对时间控制的新控制算法.分析触发时间与输出电压之间的关系及触发方法,电机负载、功率因数与节能之间的关系,提出了功率因数控制器控制算法的两种控制方案,给出了控制算法程序框图,使单片机的软件设计实施方案更加方便.

Insect source-sink dynamics are vital to ecologically intensive pest management. Maintaining sink plant hosts,or "trap crops",and destroying alternate hosts or breeding places adjacent to the field crop are effective pest management strategies for some arthropods. However,determining whether a host acts as a source or a sink is challenging, especially when the pest species is highly mobile and polyphagous. The western tarnished plant bug,Lygus hesperus,is highly polyphagous,and can utilize >300 hosts. Its presence has been documented in 26 roadside weed hosts in the Texas High Plains.Previous studies demonstrated that L. hesperus prefer alfalfa over cotton and several alternate weed hosts.A four-year project involved surveying and sampling for L. hesperus in the agricultural landscapes of several sub-regions of the southwestern United States,including the Texas High Plains. In Texas,geographic information of the landscape vegetation complex was compiled from a 150 km radius in the Texas High Plains. In one study,fifty irrigated cotton fields representing the crop diversity within this region were sampled via sweep-net for 10 weeks. This effort also included sampling of up to six noncotton insect habitats within a 3 km radius of each field. Seasonal average L. hesperus abundance data were regressed with 27 field characteristics( variables),including habitat-specific land cover,distance between focal cotton fields and non-cotton habitats,longitude,latitude,elevation,habitat heterogeneity index,and several environmental / ecological variables. Significant variables were selected using a stepwise regression at 15% probability rate. A 10-parameter linear model explained 93% of the variation in the data. Major parameters contributing significantly to variation in L. hesperus abundance in cotton were corn and sunflower acreages,focal cotton field distances from several non-cotton hosts,and habitat heterogeneity index. In addition,field marking-and-capture studies were conducted using protein markers and enzyme-linked immunosorbent assays to characterize L. hesperus intercrop movement behavior. The field marking-and-capture approach can be used to study the effects of various crop management practices on L. hesperus intercrop movement and can potentially be applied to other pests and cropping systems.

Majority of non-Newtonian fluids are pseudoplastic with shear-thinning property,which means that the viscosity will be different in different parts of the stirred tank.In such mixing process,it is difficult to predict accurately the power consumption and mean shear rate for designing novel impeller.Metzner-Otto method is a widely accepted method to solve these questions in mixing non-Newtonian fluids.As a result,Metzner-Otto constant will become a key factor to achieve an optimum way of economical mixing.In this paper,taking glycerine and xanthan gum solutions as research system,the power consumption,stirred by the impeller composed of perturbed six-bent-bladed turbine(6PBT)with differently geometrical characteristics in a cylindrical vessel,is studied by means of computational fluid dynamics(CFD).The flow is modeled as laminar and a multiple reference frame(MRF)approach is used to solve the discretized equations of motion.In order to determine the capability of CFD to forecast the flow process,the torque test experiment is used to measure the glycerine solution power consumption.The rheological properties of the xanthan gum solutions are determined by a Brookfield rheometer.It is observed that the power consumption predicted by numerical simulation agrees well with those measured using torque experiment method in stirring glycerine solution,which validate the numerical model.Metzner-Otto constant is almost not correlated with the flow behavior index of pseudoplastic fluids.This paper establishes the complete correlations of power constant and Metzner-Otto constant with impeller geometrical characteristics through linear regression analysis,which provides the valuable instructions and references for accurately predicting the power consumption and mean shear rate of pseudoplastic fluids in laminar flow,comparatively.

头屯河水库除险加固工程建设造成新增水土流失,对该项工程建设期可能产生水土流失的特点和形式进行了分析,结合头屯河水库除险加固工程可行性研究报告和现场查勘情况,进行综合分析确定.采用土壤侵蚀模数法,运用经验公式进行水土流失量的估算,从而预测出库区内新增水土流失量,初步分析确定了头屯河水库除险加固工程水土保持的重点区域,为今后水库的水土保持综合治理提供了科学的决策依据.

介绍了变频调速技术的节能原理,阐述了基于PLC和变频器控制的恒压供水特点,完成了一台变频器控制四台水泵实现恒压供水的具体要求,设计了硬件控制回路和软件编程方法.实际运行证明,变频恒压供水系统控制简单、可靠性高、保护功能完善、节能效果明显.

小浪底水库作为黄河流域水沙调控体系的重要组成部分,通过对国内外已有的水库壅水明流排沙、异重流潜入条件的分析,探讨了小浪底水库异重流预测的现状和难点,并提出了初步解决方案.今后须加强库区水沙因子测验,利用数学模型和物理模型两种手段,研究不同库段、不同流态的水沙输移规律,从而提高计算、预测水库排沙的精度,为小浪底水库排沙预测方法提出了方向.

利用黄壁庄水库水质监测资料,对水体水体富营养化变化情况,属于轻度富营养或中度富营养程度.并对水体叶绿素与水温、总磷、总氮的相关关系进行分析,结果表明:温度和总磷在时间上变化一致;而总氮变化呈抛物线状,最低点在总氮含量2.5mg/L附近.最后提出黄壁庄水库水体富营养化的预防和治理措施.