双机制Stacking集成模型在短时交通流量预测中的应用

交通流量预测对于智能交通管理决策具有重要意义,为克服传统单一模型预测精度低、稳定性不足,同时为解决Stacking集成模型对基学习器输出信息利用率不高的问题,提出了一种双机制Stacking集成模型.双机制包括内机制和外机制,内机制通过在元学习器中引入注意力机制来调整网络中的特征信息,外机制通过在基学习器中融入动态权重系数来调整基学习器的输出信息.通过内外结合的双机制实现对基学习器输出信息动态变动规律的挖掘和提取并增强对基学习器输出信息的利用率,从而提升模型的预测精度和稳定性.选取I5NB高速公路上的76898条数据为实证研究对象,进行了基于随机森林、GBDT(gradient boosting decision tree)和Xgboost(extreme gradient boosting)单一模型、传统Stacking集成模型及双机制Stacking集成模型的预测对比分析.实证结果证明双机制Stacking集成模型预测精度最高,验证了该模型在短时交通流量预测中的有效性.     

基于群智能的信息认知机制研究

群智能计算是个体认知行为和群体认知规律抽象出的一种非传统的计算智能技术。本文论述群智能计算中的信息认知机制,以及如何利用认知科学的相关研究来探索群智能计算方法。其中主要包括群智能计算中个体和群体的信息利用和分享机制,以及在不同环境的认知过程中的信息利用机制;群智能计算中不同结构和模式的记忆与认知科学中长时记忆、短时记忆、记忆结构和记忆遗忘模型的关系,以及认知记忆机制与环境的对应关系;在不同环境或变化环境下,群智能计算各种自适应策略与社会学习理论中的直接学习和观察学习之间的关系,长期记忆与短期记忆之间在环境变化下的调整机制的关系。相关的研究将促进群智能理论和认知科学的进一步融合发展。     

基于多率采样的MASs在FDI攻击下的安全一致性

文章研究了基于多率采样（MRS）机制的多智能体系统（MASs）在虚假数据注入（FDI）攻击下的领导跟随安全一致性。在所有智能体的状态不可测量的情况下,基于智能体在MRS机制下的输出,设计了一组多率观测器来重构每个智能体的状态。假设FDI攻击发生在智能体间的通信网络上,且攻击信号有界。针对每个智能体提出了一个估计器,它可以通过仅使用领导者和其邻居的信息来估计FDI攻击信号。进一步,为了缓解FDI攻击对MASs一致性的影响提出了一个安全控制协议。然后,利用李雅普诺夫稳定性理论,获得了保证MASs领导跟随安全一致性的充分条件。最后,用仿真实例验证了主要结果的有效性。     

基于注意力机制的分层次交互融合多模态情感分析

针对基于视频的多模态情感分析中,通常在同一语义层次采用同一种注意力机制进行特征捕捉,而未能考虑模态间交互融合对情感分类的差异性,从而导致模态间融合特征提取不充分的问题,提出一种基于注意力机制的分层次交互融合多模态情感分析模型(hierarchical interactive fusion network based on attention mechanism, HFN-AM),采用双向门控循环单元捕获各模态内部的时间序列信息,使用基于门控的注意力机制和改进的自注意机制交互融合策略分别提取属于句子级和篇章级层次的不同特征,并进一步通过自适应权重分配模块判定各模态的情感贡献度,通过全连接层和Softmax层获得最终分类结果。在公开的CMU-MOSI和CMU-MOSEI数据集上的实验结果表明,所给出的分析模型在2个数据集上有效改善了情感分类的准确率和F1值。     

一种改进的微种群遗传算法

 采用种群隔离机制、算术交叉、杰出者保留策略等对微种群遗传算法进行了改进。减少了重启动次数,增强了两次重启动之间遗传优化过程的全局和局部搜索能力,使算法在尽可能保有模式识别信息的前提下进行智能搜索;采用了实数编码,减少了编码和解码过程中的计算开销;引入了自适应随机变异算子,使之在不增加循环次数的前提下,增加了利用现有种群已经获得的遗传信息进行有效搜索的次数;引入了异种机制,有效提高了微种群遗传算法收敛于全局最优解的概率,加快了收敛速度。最后,标准测试函数的测试结果证明了这一改进的微种群遗传算法能够用远低于标准遗传算法的计算代价获得更佳的优化效果。     

面向食品安全领域的个性化知识搜索系统研究

大数据时代,从海量的数据中发现对用户有用的知识成为研究领域重要的问题.通过集成多个搜索引擎的查询结果,实现食品安全领域中搜索信息的集成和个性化自适应排序.本文设计基于元搜索技术、知识本体和自适应的排序学习技术,实现多个搜索引擎相关查询结果集成,在对用户点击的标注和知识本体的基础上,利用基于监督学习的排序技术,实现对食品安全领域信息的个性化自适应排序.系统实现了集成多个搜索引擎的食品安全相关知识的提取和相关结果的重新排序.本研究不仅实现了多个搜索引擎食品安全信息查询相关的结果集成,而且能够根据用户的偏好实现结果的自适应排序.     

船舶避碰的自适应模糊专家系统研究

采用自适应模糊系统和神经网络方法,研究了基于模糊联想规则的避碰操纵知识表示,知识获取和自适应学习;建立了基于二值输入输出模糊联想系统的并行模糊推理机制,由此而建立的船舶避碰撞模糊专家系统具有自适应学习能力,能实现实时避碰导航。     

一个智能自适应WWW软件系统的设计与实现方法

本文描述了一个建于ＷＷＷ之上的智能自适应软件系统，该系统基本结构类似通常的智能辅助教学系统，其个别化教学机制是通过适应性学习和掌握学习策略而实现的。本系统的主要特征是（１）学习者知识状态评估是建立在其选择知识内容节点的频率和评估分数之上；（２）基于学习历史适应性呈现和产生教学内容。     

基于注意力机制的人像分割方法

注意力机制能够挖掘与任务密切相关的重要信息并抑制非重要信息，在语义分割的深层特征表示中发挥着越来越重要的作用。本研究基于广泛应用的U-Net模型，提出了一种基于注意力机制的神经网络模型，针对边缘分割模糊的问题，将U-Net的压缩路径和扩展路径中的双卷积替换为卷积核选择模块，该模块允许网络的每一层根据输入信息进行自适应调整接受野的大小；另外，针对人像分割网络存在不同尺度的全局上下文信息被忽略的问题，采用多尺度预测融合的方法来利用不同尺度的全局信息，并采用双注意力模块汇总空间和通道两方面的注意力信息。大量实验表明，本文中方法的性能与U-Net、UNet++和Attention U-Net等网络相当或更好。     

工业信息物理系统间隙DoS攻击的自适应事件触发稳定控制

针对具有间隙拒绝服务（DoS）攻击的工业信息物理系统（ICPS）,研究一种基于观测器的自适应事件触发稳定控制方案。首先构造一个观测器估计系统状态,并采用一种新的自适应事件触发通信方案以节约网络资源;然后通过受频率和持续时间限制的间隙DoS攻击对ICPS的影响建立攻击模型,将受到DoS攻击的ICPS划分为DoS攻击活跃期系统和DoS攻击休眠期系统,并用一些过去成功触发状态重构当前受到攻击的状态,得到基于动态估计器的攻击补偿机制,保证系统在DoS攻击活跃期间的渐进稳定;最后运用分段Lyapunov泛函方法、Jensen’s不等式和Schur补引理,得到系统的稳定条件,并提出自适应事件触发参数、观测器增益和控制器增益的协同设计方案。用间歇反应器系统模拟间隙DoS攻击下基于自适应事件触发的ICPS系统稳定性能。仿真结果表明,自适应事件触发策略和基于动态估计器的补偿机制不仅能够提升系统的稳定性,还能有效降低数据传输的次数,系统在静态事件触发策略下的触发次数大约是在自适应事件触发策略下的4.5倍。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that