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HQNN-SFOP: Hybrid Quantum Neural Networks with Signal Feature Overlay Projection for Drone Detection Using Radar Return Signals-A Simulation

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Computers, Materials and Continua 2024年第1期81卷 1363-1390页

作者： Wang, Wenxia xu, jinchen Ding, Xiaodong Song, Zhihui Huang, Yizhen Zhou, Xin Shan, Zheng School of Cyberspace Security Information Engineering University Zhengzhou 450001 China

With the wide application of drone technology, there is an increasing demand for the detection of radar return signals from drones. Existing detection methods mainly rely on time-frequency domain feature extraction and classical machine learning algorithms for image recognition. This method suffers from the problem of large dimensionality of image features, which leads to large input data size and noise affecting learning. Therefore, this paper proposes to extract signal time-domain statistical features for radar return signals from drones and reduce the feature dimension from 512 × 4 to 16 dimensions. However, the downscaled feature data makes the accuracy of traditional machine learning algorithms decrease, so we propose a new hybrid quantum neural network with signal feature overlay projection (HQNN-SFOP), which reduces the dimensionality of the signal by extracting the statistical features in the time domain of the signal, introduces the signal feature overlay projection to enhance the expression ability of quantum computation on the signal features, and introduces the quantum circuits to improve the neural network's ability to obtain the inline relationship of features, thus improving the accuracy and migration generalization ability of drone detection. In order to validate the effectiveness of the proposed method, we experimented with the method using the MM model that combines the real parameters of five commercial drones and random drones parameters to generate data to simulate a realistic environment. The results show that the method based on statistical features in the time domain of the signal is able to extract features at smaller scales and obtain higher accuracy on a dataset with an SNR of 10 dB. On the time-domain feature data set, HQNNSFOP obtains the highest accuracy compared to other conventional methods. In addition, HQNN-SFOP has good migration generalization ability on five commercial drones and random drones data at different SNR conditions. Ou

关键词： Time domain analysis

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流态模型对小型太阳能烟囱流场特性影响分析

太阳能学报 2024年第1期45卷 80-86页

作者：聂晶苏昊贾靖高虹闫素英许金晨内蒙古工业大学能源与动力工程学院呼和浩特010051 内蒙古可再生能源重点试验室呼和浩特010051

在小型太阳能烟囱(SC)的数值模拟计算中,选取不同流态模型(层流、湍流或转捩)计算结果不同。该文使用光线追踪和环境侧风模拟,对不同流态模型进行数值模拟计算,对比分析计算结果与试验数据。结果表明:不同时刻转捩模型下流体湍流强度、... 详细信息

在小型太阳能烟囱(SC)的数值模拟计算中,选取不同流态模型(层流、湍流或转捩)计算结果不同。该文使用光线追踪和环境侧风模拟,对不同流态模型进行数值模拟计算,对比分析计算结果与试验数据。结果表明:不同时刻转捩模型下流体湍流强度、受环境侧风扰动程度与层流模型、湍流模型相比更小,在计算中使用转捩模型更准确,为小型SC流场模拟计算的模型选择提供参考。

关键词：太阳能烟囱转捩流热分析数值分析

基于静态充电需求的城市公共充电桩选址决策模型

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北京交通大学学报 2024年第3期48卷 48-54页

作者：王志成徐金辰常燕燕巴天星沈阳市规划设计研究院有限公司交通规划院沈阳110004

为科学发展新能源交通基础设施,对城市公共充电桩的建设选址优化展开研究.首先,考虑充电行为与停车行为的强关联性,提出静态充电需求的概念.其次,结合城市停车设施分布与安全间距要求,确定备选点位集合,并构建选址优化模型,在实现满足... 详细信息

为科学发展新能源交通基础设施,对城市公共充电桩的建设选址优化展开研究.首先,考虑充电行为与停车行为的强关联性,提出静态充电需求的概念.其次,结合城市停车设施分布与安全间距要求,确定备选点位集合,并构建选址优化模型,在实现满足周边需求的同时,适应中心城区新能源汽车发展的总体规律,实现投建主体的收益最大化.再次,通过引入Voronoi图,平均划分备选点位之间服务范围的空间叠加,简化原模型的约束条件,并设计“两阶段”算法,降低原问题可行域维度,提升求解迭代效率.最后,以沈阳市三环内的城市核心区为实例进行分析.研究结果表明:基于静态充电需求的城市公共充电桩选址决策模型可通过优先在静态充电需求旺盛的区域布局城市公共充电桩,其在给定参数下,与传统的P-中心模型和集覆盖模型相比,充电收益可提升12.7%以上,充电服务覆盖范围更广,可以更好地保障新能源汽车发展,引导城市交通绿色化转型.

关键词：城市交通公共充电桩选址模型静态充电需求 Voronoi图

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组元层厚对TC4/Al_(3)Ti微叠层复合材料性能影响

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特种铸造及有色合金 2024年第1期44卷 116-120页

作者：许金琛景栋孟令刚刘运峰周秉文张兴国大连理工大学材料科学与工程学院大连1160002.大连理工大学材料科学与工程学院大连116000 大连理工大学宁波研究院宁波3150323.大连理工大学宁波研究院宁波315032

以TC4箔材和纯Al箔材为原材料,用高真空热压法制备了TC4/Al_(3)Ti微叠层复合材料,研究了组元层厚对复合材料组织与性能的影响。使用金相显微镜、X射线衍射仪、扫描电镜和场发射电子探针对复合材料的显微组织、裂纹断口进行分析。结果表... 详细信息

以TC4箔材和纯Al箔材为原材料,用高真空热压法制备了TC4/Al_(3)Ti微叠层复合材料,研究了组元层厚对复合材料组织与性能的影响。使用金相显微镜、X射线衍射仪、扫描电镜和场发射电子探针对复合材料的显微组织、裂纹断口进行分析。结果表明,当试样厚度及试样内Al_(3)Ti体积分数一定时,组元层厚越小,复合材料力学性能越优异。当堆叠层数为55层时,组元层厚最小,材料性能最佳,其抗弯强度为970 MPa,垂直于层的抗压强度为1 307 MPa,平行于层的抗压强度为1 206 MPa。

关键词： Al-Ti微叠层复合材料真空热压力学性能断口形貌

基于多类型计算重写的浮点表达式精度优化方法

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计算机科学 2024年第4期51卷 86-94页

作者：郝江伟杨鸿儒夏媛媛刘毅许瑾晨庞建民信息工程大学网络空间安全学院郑州450001 数学工程与先进计算国家重点实验室江苏无锡214125 中国科学院软件研究所天基综合信息系统重点实验室北京100190

表达式重写是精度优化领域的新兴方法,其核心思想是在不改变表达式精度类型的前提下,将其变换为语义上等价的表达式以尝试提升精度。然而,面对庞大的变换规则和变换空间,如何选取合适的变换策略成为了重写方法的问题所在。针对上述问题... 详细信息

表达式重写是精度优化领域的新兴方法,其核心思想是在不改变表达式精度类型的前提下,将其变换为语义上等价的表达式以尝试提升精度。然而,面对庞大的变换规则和变换空间,如何选取合适的变换策略成为了重写方法的问题所在。针对上述问题,提出了一个基于多类型计算重写的浮点表达式精度优化方法,支持包括函数计算、四则运算的表达式,并实现了表达式重写工具exprAuto。区别于其他精度优化工具侧重于对子表达式的替换,exprAuto更注重对表达式运算顺序的变换。exprAuto在对表达式化简和数学变换后,通过多项式变换获取不同的计算顺序,并尝试减少运算次数以提升精度,最终生成一个包含不同计算顺序的等价表达式集合,通过排序筛选和误差检测从中选出最终的精度优化结果。文中选取41个FPBench标准集中的表达式和18个常见数学函数的近似多项式作为测试用例,在经exprAuto优化后,所提方法相比原式最大误差降低了45.92%,平均误差降低了34.98%;针对其中的18个近似多项式,相比原式最大误差降低了58.35%,平均误差降低了43.73%。实验结果表明,exprAuto可以有效提升表达式尤其是多项式的精度。

关键词：浮点计算精度优化重写变换

相变储热太阳能上升气流塔:清洁能源层级利用的新路径

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科学技术创新 2024年第20期 213-216页

作者：赵蒙元唐雪冲聂晶苏昊许金晨上海勘测设计研究院有限公司上海三峡陆上新能源投资有限公司内蒙古呼和浩特内蒙古工业大学能源与动力工程学院内蒙古呼和浩特

太阳能上升气流塔热发电技术是一项新兴的太阳能热利用技术。本文以干旱半干旱地区草场保护为导向,太阳能上升气流塔装置中进行牧草或其他农作物种植,为养殖用草提供来源以及经济效益,并且在内部集成相变材料储热,调控棚内作物适宜生长... 详细信息

太阳能上升气流塔热发电技术是一项新兴的太阳能热利用技术。本文以干旱半干旱地区草场保护为导向,太阳能上升气流塔装置中进行牧草或其他农作物种植,为养殖用草提供来源以及经济效益,并且在内部集成相变材料储热,调控棚内作物适宜生长温度。结果表明:在经过相同时长的加热及冷却后,相变蓄热层最终的中间层平均温度比铝制蓄热层高1.09%,证明了潜热释放对棚内温度调控的有效性,并且建造太阳能上升气流塔种植系统的成本相对于其他大棚降温设备更低廉,能够在环境友好的前提下牧草种植和太阳能热发电并线运行,实现能源的层级利用。

关键词：太阳能热利用生态保护相变材料数值模拟

An all-in-one FeO_(x)-rGO sponge fabricated by solid-phase microwave thermal shock for water evaporation and purification

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Journal of Environmental Sciences 2024年第4期138卷 671-683页

作者： Youkun Sun Xiuwen Zhao xueling Song jinchen Fan Junhe Yang Yingchun Miao Shuning Xiao School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China Prytula Igor Collaborate Innovation Center for Diamond Shanghai Jian Qiao UniversityShanghai 201306China

Developing high-efficiency photothermal seawater desalination devices is of significant importance in addressing the shortage of *** much effort made into photothermal materials,there is an urgent need to design a rapidly synthesized photothermal evaporator for the comprehensive purification of complex ***,we report on all-in-one FeOx-rGO photothermal sponges synthesized via solid-phase microwave thermal *** narrow band gap of the semiconductor material Fe_(3)O_(4) greatly reduces the recombination of electron-hole pairs,enhancing non-radiative relaxation light *** abundantπorbitals in rGO promote electron excitation and thermal vibration between the *** of the surface hydrophilicity and hydrophobicity promotes salt resistance while simultaneously achieving the purification of various complex polluted *** optimized GFM-3 sponge exhibitedan enhanced photothermal conversion rate of 97.3% and a water evaporation rate of 2.04 kg/(m^(2)·hr),showing promising synergistic water purification *** findings provide a highly efficient photothermal sponge for practical applicationsof seawater desalination and purification,as well as develop a super-rapid processing methodology for evaporation devices.

关键词： Desalination Photothermal device Microwave synthesis Water purification FeO_(x)-rGO

A Novel Scheduling Framework for Multi-Programming Quantum Computing in Cloud Environment

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Computers, Materials & Continua 2024年第5期79卷 1957-1974页

作者： Danyang Zheng jinchen Xv Feng Yue Qiming Du ZhihengWang Zheng Shan Information Engineering University Zhengzhou450001China

As cloud quantum computing gains broader acceptance,a growing quantity of researchers are directing their focus towards this ***,the rapid surge in demand for cloud-based quantum computing resources has led to a scarcity,which in turn hampers users from achieving optimal ***,cloud quantum computing service providers require a unified analysis and scheduling framework for their quantumresources and user jobs to meet the ever-growing usage *** paper introduces a new multi-programming scheduling framework for quantum computing in a cloud *** framework addresses the issue of limited quantum computing resources in cloud environments and ensures a satisfactory user *** introduces three innovative designs:1)Our framework automatically allocates tasks to different quantum backends while ensuring fairness among users by considering both the cloud-based quantum resources and the user-submitted tasks.2)Multi-programming mechanism is employed across different quantum backends to enhance the overall throughput of the quantum *** comparison to conventional task schedulers,our proposed framework achieves a throughput improvement of more than two-fold in the quantum cloud.3)The framework can balance fidelity and user waiting time by adaptively adjusting scheduling parameters.

关键词： Quantum computing scheduling multi-programming qubit mapping

Influence of nitrogen status on fermentation performances of non-Saccharomyces yeasts:a review

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Food Science and Human Wellness 2024年第2期13卷 556-567页

作者： jinchen Li Mengmeng Yuan Nan Meng Hehe Li Jinyuan Sun Baoguo Sun Key Laboratory of Brewing Molecular Engineering of China Light Industry Beijing Key Laboratory of Flavor ChemistryBeijing Technology&Business UniversityBeijing 100048China

Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic *** influences are imposed on yeast growth and fermentation performances including the formation of secondary *** cerevisiae,the main yeast responsible for fermentation,has been studied extensively regarding nitrogen *** the other hand,a similar study for non-Saccharomyces yeasts,whose contributions to winemaking have gradually been acknowledged,remains to be fully explored,with a few studies being *** review starts by discussing nitrogen impacts on non-Saccharomyces yeast growth and fermentation kinetics in different case scenarios,then proceeds to summarize the nitrogen preferences of individual yeast strains with regulation mechanisms elucidated by recent *** discussions on the influences on the production of volatile compounds and proposed pathways therein are made,followed by future work suggested as the final *** summarizing the nitrogen impacts on non-Saccharomyces yeasts throughout alcoholic fermentation,this review will be helpful in obtaining a more comprehensive view on these non-conventional wine yeasts in terms of nutrient requirements and corresponding volatile *** gaps will therefore be elucidated for future research.

关键词： Non-Saccharomyces yeasts Nitrogen Fermentation kinetics Nitrogen preference Wine aroma