利用山路引理、Hölder不等式、嵌入不等式和估值等,研究了一类含临界非局部项且位势在无穷远处消失的Schrödinger-Poisson系统的非平凡解的存在性.首先利用嵌入不等式证明了泛函具有紧性,然后利用截断函数对泛函进行了估值,最后用变分方法证明了该系统至少有一个非平凡解.所得结果丰富了椭圆型方程解的相关理论.
讨论了一类切换正时滞系统的稳定性和镇定性.首先,通过构造多元共正李雅普诺夫泛函,得到了切换正时滞系统在可容许边依赖平均驻留时间(AED-ADT)切换信号下的有限时间稳定的充分条件;其次,设计了一类状态反馈控制器,并给出了闭环系统在AED-ADT切换信号下具有有限时间稳定的判据.最后,利用两个算例验证了所得结果的正确性.
研究了一类Bézier型Szász-Mirakjan-Kantorovich算子.首先,给出了该类算子的一阶、二阶中心矩;然后,利用Lipschitz型不等式得到了该类算子的范数不等式,并利用二阶连续模和K泛函讨论了该算子的逼近性质;最后,给出了该类算子对Lipschitz函数类的逼近定理.
In this paper, a cortex-basal ganglia model about Parkinson’s disease with two time delays is studied, and the critical conditions for Hopf bifurcation are derived. The results show that time delays can change the state of basal ganglia. The basal ganglia is stable when the delays are small. However, when the time delay is greater than the corresponding bifurcation critical point, different types of oscillations occur in the basal ganglia. The larger the time delays, the more active the neuronal clusters in the basal ganglia. Furthermore, the bidirectional Hopf bifurcation is found by studying the connection weights between different neural nuclei. Finally, the influence of connection weight and time delay which are related to the internal segment of the globus pallidus on its oscillation is discussed. Research shows that reducing the connection weight and the corresponding time delay in excitatory neuronal clusters, or increasing the connection weight and decreasing the corresponding time delay in inhibitory neuronal clusters, can improve the oscillation of Parkinson’s disease.
由于Mn离子的发射光谱可与植物光敏色素的吸收光谱重叠,因此其可被应用于植物照明领域中.但由于Mn离子的发射光强度较低,使得其在实际应用中受到很大限制;因此,加强掺杂Mn离子材料的吸收能力对提高其在植物照明领域中的应用具有重要意义.为此,对近年来掺杂Mn4+离子和Mn2+离子荧光粉的发光特性的相关文献进行了综述,以期为研究具有优良特性的新型植物照明用荧光粉提供参考.
利用修正的辅助方程法研究了 Kadomtsov-Petviashvili-Benjamin-Bona-Mahony(KP-BBM)方程的行波解,得到了该方程的双曲余切函数解和雅克比椭圆函数解,并利用Matlab软件给出了所得解的性态行为.
为了提高非易失性存储器的存储密度和存储效率,提出了一种基于忆阻器的2T2M存储阵列.该阵列采用10×10的交叉结构.Simulink仿真实验证明,该存储阵列不仅可以有效增加存储单元的存储密度和提高存储效率,而且电路结构简单;因此,该存储阵列可为高存储密度电路和图像存储的设计提供参考.
将6种不同的凸函数与非对称的Green-Osher不等式相结合,得到了两个凸体处于膨胀位置时的相对曲率积分型不等式,该结果推广了文献[5]中关于闭凸曲线型积分不等式的相关结果.
利用射频磁控溅射方法在玻璃和Si(111)衬底上沉积了 CdSe薄膜,并研究了不同溅射压强对薄膜的结构、光学和电学性能的影响.X射线衍射分析表明,所有样品均沿(111)面择优生长,晶粒尺寸随溅射压强的增大而减小.透射光谱分析表明,CdSe薄膜在红外光区域具有较大的透射率,薄膜的带隙随溅射压强的增大表现出先增大后减小的趋势.霍尔效应测试表明,随着溅射压强的增加,电阻率出现先增大后减小的趋势,载流子浓度则出现先减小后增大的趋势.该研究结果可为CdSe薄膜在光电器件方面的应用提供参考.
文本情感分类方法在网络舆情、股票预测等诸多方面有着广泛的应用.为了更好地研究文本情感分类方法,对近年来基于情感词典的文本分类方法、机器学习的文本分类方法、深度学习的文本分类方法以及方面级文本分类方法、隐式文本情感分类方法、跨域文本情感分类方法的相关文献进行了梳理和综述,并对文本情感分类方法的研究方向进行了展望.
针对属性权重未知的多属性决策问题,在Z概率语言术语集(ZPLTS)环境下,提出了一种改进的PROMETHEE Ⅱ(preference ranking organization method for enrichment evaluations Ⅱ)方法.在该方法中,各评价信息的综合可靠度由评价本身的可靠度和决策者给出的可靠度来确定,并由此进一步确定属性的权重;距离测度采用扩展的欧式距离,该方法在ZPLTS环境下能够克服不同Z概率语言值(ZPLVs)之间的距离均为0所带来的决策偏差.实例研究表明,该方法在反映原始数据信息和确定未知属性权重方面显著优于TOPSIS方法和传统的PROMETHEE Ⅱ方法,因此该方法可应用于多属性决策问题中.
为了研究非厄米混合系统中的快慢光传播性质,提出了一个非厄米磁量子电动力学(QED)混合模型.该模型由2个微波腔和1个钇铁石榴石组成.模型采用强泵浦场驱动磁子,采用弱探测场探测微波腔.研究表明:通过调节腔与磁子之间的相互作用强度和微波腔与磁子的耗散比,可以增加磁子诱导放大效应和提高快慢光的传播速度.该研究结果可为量子光学操纵、量子信息存储以及灵敏光开关的研究提供参考.
研究了一类Hadamard型分数阶微分方程的边值问题.首先,将微分方程边值问题转化为等价的积分方程问题;其次,根据边值条件求出微分方程相应的格林函数,并利用格林函数的性质得出微分方程所对应的Lyapunov不等式;最后,分别利用Banach压缩映像原理和Leray-Schauder不动点定理证明了该类非线性边值问题解的存在性,并通过算例验证了所得结果的正确性.
以东北贯众提取物为主药,采用酸碱分开制粒后压片工艺制备了一种具有驱虫效果的东北贯众提取物泡腾片.正交实验显示,该泡腾片的最佳配方(质量分数)为:东北贯众提取物4.0％,复合维生素0.2％,柠檬酸29.5％,碳酸氢钠15.5％,糖粉15.0％,滑石粉0.15％,β-环糊精35.65％.经测定显示,该泡腾片对小鼠腹腔内的弓形虫的抑制率与螺旋霉素相当,且其重量差异、崩解时限、硬度、pH、发泡量均符合2020版《中华人民共和国药典》中的相关标准,因此该东北贯众提取物泡腾片可作为一种潜在的宠物驱虫药物进行进一步研究.
为了更好地解决区间值犹豫模糊集(IVHFS)群决策问题,利用平面向量建立了一种可以从多个角度判定方案优劣的群决策模型.首先,在IVHFS中定义了区间值隶属度的中位数、区间值隶属度的清晰度,并以此通过构造平面向量来刻画IVHFS.其次,通过利用平面向量簇刻画IVHFS建立了区间值犹豫模糊元(IVHFE)的外部固定函数模型和内部稳定函数模型,给出比较2个IVHFE大小的准则和计算二者距离的方法,并根据所有方案的外部固定函数值和内部稳定函数值分别计算了测评准则的外部权重和内部权重(依据外部权重与内部权重的相离程度值来确定测评准则的综合权重).再次,通过利用参数调整方案的外部固定函数值与内部稳定函数值的比例计算了各个方案的综合决策值.最后,利用数值算例验证了本文方法的可行性.
In order to improve the predicting accuracy of the aging population, a combinational forecasting model which is based on induced ordered weighted averaging（IOWA） operators and correlation coefficient is established by using the residual modified GM（1,1） model, the gray-BP neural network model and the Logistic forecasting model as the single model.Using this model forecast the aging population（≥65 years old） of the eastern, central, western and northeastern regions and the whole country for 2000-2020 in China, the forecasting result shows that the predicting effect of the combinational forecasting model is significantly better than that of the above three single forecasting models, indicating the model can effectively improve the predicting accuracy of the aging population.Finally, the combinational forecasting model is used to predict the number of ageing population in the eastern, central, western and northeastern parts of China and the whole country in the next 10 years: the number of ageing population in China generally shows a gradual growth trend, and the differences in the aging process between regions are also increasing, of which the ageing population in the east grows relatively fast and the growth in the central region is relatively slow.The forecasting result can provide a reference for the formulation of Chinese aging population policy.
The local and global stability of the equilibrium points of a predator-prey model with linear harvesting and additional food source are studied.The correctness of the main conclusions are verified by numerical simulations.The results show that when the predator has more additional food source, it will lead to the extinction of the prey population; when the predator has less additional food source, the small harvesting will keep the coexistence of the prey and predator populations, but the excessive harvesting will lead to the extinction of the prey population.
The 1/G expansion method is adopted for solving a class of time-space fractional-order Klein-Gordon equations.Computed results present abundant traveling wave solutions, which mainly include two parts: solitary wave solutions and distorted wave solutions.Furthermore, the part of phase diagrams of the obtained solutions are analyzed, and the results show that the obtained solutions is valid.The research extends the application scope of the fractional Klein-Gordon equations.
Existence of solutions for semilinear elliptic equations involving weight functions in unbounded domains is proved by using Sobolev-Hardy inequality and variational methods, which extends the existence of solution on bounded domain and in the whole space to the unbounded outer domain.
In order to solve the multi-attribute group decision making problem of the probabilistic hesitant fuzzy sets, a decision model is constructed to compare the comprehensive attribute value of each scheme under different dimensions.Firstly, the membership degree and probability of the probabilistic hesitant fuzzy sets are written in the form of two-dimensional coordinates, and on this basis, the two-dimensional geometric distance model and the two-dimensional deviation degree coefficient model of the probabilistic hesitant fuzzy elements are established.Secondly, the membership degree of the probabilistic hesitant fuzzy sets is assigned to the corresponding weight of the evaluation experts, and the membership degree, probability and the assigned weight of the evaluation experts are described by three-dimensional coordinates, accordingly establish the three-dimensional geometric distance model and the three-dimensional deviation degree coefficient model of the probabilistic hesitant fuzzy elements.Thirdly, the comprehensive values of the probabilistic hesitant fuzzy elements under two dimensions and three dimensions were calculated respectively, and the Maclaurin symmetric average operator is used to aggregate and rank the comprehensive values of the probabilistic hesitant fuzzy elements under the above two dimensions.Finally, an example is used to in the two dimensional analysis of the algorithm are verified.The results show that the algorithm in two dimensions can be effective scheme of the sort, but because in a three-dimensional perspective to establish a decision-making model could reflect the preference of evaluation experts, the decision-making effect of the model is relatively better.
