风光互补无人监测船神经网络MPPT优化策略

为提高风光互补无人监测船长期作业的续航能力和工作稳定性,针对传统风光互补发电的优化最大功率点追踪(MPPT)控制策略需要对风力发电和光伏发电两个子系统分别进行MPPT控制而导致的综合输出功率不高问题,提出径向基函数(RBF)神经网络和单个升压(Boost)电路MPPT优化控制策略。该方案以风力发电和光伏发电两个子系统输出的电流和电压作为RBF神经网络的输入电流和电压,通过神经网络输出统一的占空比,经由单个Boost电路调整风光互补发电系统的输出电压,提高风光互补发电系统的综合输出功率。使用MATLAB仿真进行验证,结果表明此优化策略与传统MPPT控制策略相比综合输出功率更高且更稳定。     

基于生成对抗网络的控制系统参数辨识

自然科学和社会科学领域内的控制系统往往表现出很强的非线性行为且被控对象往往与多个输入项相关,因此,对其系统的参数辨识更加困难。本文提出了一种基于改进生成对抗网络的参数辨识算法,用于解决非线性多输入多输出系统的参数辨识问题。该参数辨识方法对经典的生成对抗网络的输入信号及网络架构作出改进,将未知参数变换为网络权重,利用交叉熵损失和梯度下降法推导了待辨参数的迭代更新算法,并通过实例仿真验证了该算法在参数估计上的有效性和稳定性。     

江淮丘陵区典型农业小流域磷素输出时程变化特征

以安徽省滁州市花山流域为例,开展水量与地表径流磷素浓度同步监测,研究了江淮丘陵区典型农业小流域总磷浓度和输出负荷的时程变化特征和不同连续天数最大输出负荷占全年负荷的比例特征。研究结果表明:花山流域总磷浓度年内变化对于降雨径流过程存在响应关系,年内总磷浓度汛期普遍高于非汛期;流域总磷输出负荷在年中呈现脉冲式输出特点,且输出主要集中在夏季汛期的雨洪时段,在不到全年10%的时段内,花山流域的总磷输出负荷占到全年输出负荷的50%以上。     

一种基于SVM后验概率的MRF分割方法

提出了一种基于SVM后验概率的MRF分割方法,将支持向量机的后验概率应用于Markov随机场方法中,通过贝叶斯公式将对样本条件概率的估计转换为后验概率估计,再通过对SVM决策函数输出的映射来产生后验概率,并将SVM估计的后验概率信息带入MRF模型实现分割,从而完成了一种新的Markov随机场模型的分割方法.实验结果表明,采用此方法分割纹理图像可以获得较好的分割结果.     

基于水-汽平衡器的离轴积分腔输出光谱法(ICOS)走航观测海水中溶解CH4

A new off-axis integrated cavity output spectroscopy(ICOS) is coupled to Weiss equilibrator for continuous highresolution dissolved methane measurement in the surface ocean. The time constant for the equilibrator in freshwater at room temperature is determined via dis-equilibration and re-equilibration experiments. The constant for methane is about 40 min. The system is calibrated using a standard gas of 3.980×10–6, and the precision of the ICOS for methane is 0.07%. This system is equipped onboard to measure the spatial distribution in methane concentrations of South Yellow Sea(SYS) along the cruise track from Shanghai to Qingdao. Result shows that the methane concentration varies from 2.79 to 36.36 nmol/L, reveals a significant pattern of methane source in SYS, and a distinct decreasing trend from south to north. The peak value occurs at the coast area outside mouth of the Changjiang River, likely to be affected by the Changjiang diluted water mass dissolving a large amount of rich in methane. Moreover, all the surface waters are oversaturated, air-to-sea fluxes range from 98.59 to 5 485.35 μmol/(m2·d)(average value(1 169.74±1 398.46) μmol/(m2·d)), indicating a source region for methane to the atmosphere. Key words: methane, equilibrator, off-axis integrated cavity output spectroscopy(ICOS), South Yellow Sea     

冬季台湾海峡210Po和210Pb的分布特征及颗粒物的输出

~(210) Po and ~(210) Pb are increasingly used to constrain particle dynamics in the open oceans, however they are less used in coastal waters. Here, distributions and partitions of ~(210) Po and ~(210) Pb were examined in the Taiwan Strait, as well as their application to quantify particle sinking. Activity concentrations of dissolved ~(210) Po and ~(210) Pb(0.6 μm)ranged from 1.21 to 7.63 dpm/(100 L) and from 1.07 to 6.33 dpm/(100 L), respectively. Activity concentrations of particulate ~(210) Po and ~(210) Pb varied from 1.96 to 36.74 dpm/(100 L) and from 3.11 to 38.06 dpm/(100 L). Overall,particulate ~(210) Po and ~(210) Pb accounted for the majority of the bulk ~(210) Po and ~(210) Pb. 210 Po either in dissolved or particulate phases showed similar spatial patterns to 210 Pb, indicating similar mechanisms for controlling the distributions of ~(210) Po and ~(210) Pb in the Taiwan Strait. The different fractionation coefficients indicated that particles in the Zhemin Coastal Current(ZCC) inclined to absorb 210 Po prior to 210 Pb while they showed an opposite effect in the Taiwan Warm Current(TWC). Based on the disequilibria between ~(210) Po and ~(210) Pb, the sinking fluxes of total particulate matter(TPM) were estimated to range from –0.22 to 3.84 g/(m2·d), showing an overall comparable spatial distribution to previous reported sediment accumulation rates. However, our sinking fluxes were lower than the sedimentation rates, indicating a sediment resuspension in winter and horizontal transport of particulate matter from the Taiwan Strait to the East China Sea.     

水雷目标探测攻击指令正确性评判方法研究

主动攻击水雷是一种战斗部主动航行接近目标,并对其实施攻击的水雷,其打击误差主要受目标探测攻击点估计误差和弹道控制误差影响。因此,评判主动攻击水雷目标探测攻击指令输出正确的条件是, 目标探测攻击点估计误差也满足指标要求。对目标探测攻击指令输出正确性指标的试验数据处理及评判方法进行研究,提出了一种基于向量表达式的评判方法,软件实现简单、便捷。     

省级天气图打印输出存在“重影”的解决方法

天气图是预报员做天气预报的基本素材,在制作和发布天气预报的整套业务流程中,根据报文资料生成并填绘（或打印）出各种天气图是一个重要而基础的环节。在这个环节上应保证工作的时效性,准确性,即填给或打印出的各类天气图上的标识元素必须实时、客观、准确才能为预报员进行正确的分析、准确的判断提供最基本的先决条件。但是在前段时期的工作中,打印出的贵州省区域天气图（常称之“省图”）上,在某些台站位置处重复填绘造成出现重影且所填要素值不同。在一定程度上直接影响了预报员的工作,应予及时解决。本文基于对报文资料处理流程…     

数字地图制图中的地图输出设计

论述了在数字制图环境下地图输出的特点,在分析了地图上点、线、面符号特征和构造原理的基础上,提出了一种用于数字地图符号化输出的地图符号库数据结构.     

数字地图制图中的地图输出设计

论述了在数字制图环境下地图输出的特点,在分析了地图上点、线、面符号特征和构造原理的基础上,提出了一种用于数字地图符号化输出的地图符号库数据结构。