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Effects of Rattling Behavior of K and Cd Atoms along Different Directions in Anisotropic KCdAs on Lattice Thermal Transport and Thermoelectric Properties

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Energy & Environmental Materials 2024年第6期7卷 388-398页

作者： Yue Wang Yinchang Zhao Jun Ni Zhenhong dai Department of Physics Yantai UniversityYantai 264005China State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China

We employ advanced first principles methodology,merging self-consistent phonon theory and the Boltzmann transport equation,to comprehensively explore the thermal transport and thermoelectric properties of ***,the study accounts for the impact of quartic anharmonicity on phonon group velocities in the pursuit of lattice thermal conductivity and investigates 3ph and 4ph scattering processes on phonon *** various methodologies,including examining atomic vibrational modes and analyzing 3ph and 4ph scattering processes,the article unveils microphysical mechanisms contributing to the lowκL within *** features include significant anisotropy in Cd atoms,pronounced anharmonicity in K atoms,and relative vibrations in non-equivalent As atomic *** atoms,situated between As layers,exhibit rattling modes and strong lattice anharmonicity,contributing to the observed lowκ*** flat bands near the valence band maximum translate into high PF,aligning with ultralowκL for exceptional thermoelectric *** optimal temperature and carrier concentration doping,outstanding ZT values are achieved:4.25(a(b)-axis,p-type,3×10^(19)cm^(−3),500 K),0.90(c-axis,p-type,5×10^(20)cm^(−3),700 K),1.61(a(b)-axis,n-type,2×10^(18)cm^(−3),700 K),and 3.06(c-axis,n-type,9×10^(17)cm^(−3),700 K).

关键词： anharmonic lattice dynamics electron transport characteristics first principles calculation lattice thermal transport octahedron thermoelectric properties

Text Reasoning Chain Extraction for Multi-Hop Question Answering

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Tsinghua Science and Technology 2024年第4期29卷 959-970页

作者： Pengming Wang Zijiang Zhu Qing Chen Weihuang dai School of Data Science and Artificial Intelligence Wenzhou University of TechnologyWenzhou 325035China School of Computer Science and also with Institute of Intelligent Information ProcessingSouth China Business CollegeGuangdong University of Foreign StudiesGuangzhou 510545China School of Psychology Jiangxi Normal UniversityNanchang 330022China also with School of Science East China Jiaotong UniversityNanchang 330013China Institute of Intelligent Information Processing South China Business CollegeGuangdong University of Foreign StudiesGuangzhou 510545China

With the advent of the information age, it will be more troublesome to search for a lot of relevant knowledge to find the information you need. Text reasoning is a very basic and important part of multi-hop question and answer tasks. This paper aims to study the integrity, uniformity, and speed of computational intelligence inference data capabilities. That is why multi-hop reasoning came into being, but it is still in its infancy, that is, it is far from enough to conduct multi-hop question and answer questions, such as search breadth, process complexity, response speed, comprehensiveness of information, etc. This paper makes a text comparison between traditional information retrieval and computational intelligence through corpus relevancy and other computing methods. The study finds that in the face of multi-hop question and answer reasoning, the reasoning data that traditional retrieval methods lagged behind in intelligence are about 35% worse. It shows that computational intelligence would be more complete, unified, and faster than traditional retrieval methods. This paper also introduces the relevant points of text reasoning and describes the process of the multi-hop question answering system, as well as the subsequent discussions and expectations.

关键词： intelligent computing multi-hop quiz text reasoning document retrieval text complex network

Mitigating methane emissions:Domestic and joint efforts by the United States and China

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Environmental Science and Ecotechnology 2024年第4期20卷 2-5页

作者： Fan dai Yi Wang California-China Climate Institute The University of CaliforniaBerkeleyUSA Institutes of Science and Development Chinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

During the Glasgow climate conference,the United States(U.S.)and China jointly committed to reduce methane emissions as a prioritized area of their bilateral cooperation in addressing climate change in the *** methane's strongwarming effect,which is over 80 times more potent than carbon dioxide in the first 20 years after release,reducing methane emissions is crucial to slowing down climate change in the near future[1].1 The significance of this joint commitment was reiterated in the recent U.S.-China Sunnylands Statement on Climate Cooperation,emphasizing the urgency and importance of reducing methane emissions both within each country's borders and through collaborative efforts.

关键词： methane dioxide iterated

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乌桕生物学特性的初步研究

广西植物 1982年第1期 41-44页

作者：金代钧广西植物研究所

乌桕Sapium sebiferum Roxb.是广布于亚热带、热带的含油脂量高的油料树种。乌桕油脂在工业上用途广、耗量大,所以近年我国在南方各省都在大力营造人工林,探索桕林的速生丰产途径。我国栽培桕树利用桕油虽有千余年历史,但对乌桕的生物... 详细信息

乌桕Sapium sebiferum Roxb.是广布于亚热带、热带的含油脂量高的油料树种。乌桕油脂在工业上用途广、耗量大,所以近年我国在南方各省都在大力营造人工林,探索桕林的速生丰产途径。我国栽培桕树利用桕油虽有千余年历史,但对乌桕的生物学特性至今尚未见有系统的研究。我们从1975年起,采用调查和定点观察相结合的方法,对乌桕的生物学特性作了初

关键词：雄花序初步研究夏梢果实生长期幼树期春梢水葡萄生物学特性

A Superior Sales Mode for a Two-Echelon Supply Chain of Perishable Products

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Journal of Systems Science and Information 2024年第2期12卷 274-293页

作者： Mengqi BAO Xiaozhen dai School of Management Wenzhou Business CollegeWenzhou 325035China

This paper considers sales mode selection issues for a two-echelon supply chain of perishable products involving a supplier and a ***’purchase desire is assumed to be positive correlation with the freshness of the ***,the traditional sales mode is examined,in which the supplier and the retailer play a Stackelberg *** propose a three-layer decision model for this situation,and obtain dynamic pricing strategies and selling cycle *** is shown that the retailer has little motivation to order many perishable products so as to avoid a long selling cycle ***,the commission-charge mode is analyzed,in which the retailer declares its decision *** this mode,we demonstrate that the perishable product will be on sale during the whole shelf life under a certain *** correlation between the sales price of each stage and the remaining shelf-life length is ***,the superiority analysis for the two sales modes is *** show the relation between the selling cycle lengths of the two *** our analysis,it is shown that both the supplier and the retailer gain more profits when the commission-charge mode is adopted and the commission rate locates in a certain open ***,a numerical illustration is presented to visualize the discussed models,and some supplements are made for the acquired conclusions by the illustration.

关键词： pricing sales mode commission-charge mode selling cycle length superiority analysis

Automatic modulation recognition of radio fuzes using a DR2D-based adaptive denoising method and textural feature extraction

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Defence Technology（防务技术） 2024年第4期34卷 328-338页

作者： Yangtian Liu Xiaopeng Yan Qiang Liu Tai An Jian dai Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China China Research and Development Academy of Machinery Equipment Beijing 100089China

The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference ***,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio *** solve the above problem,a radio fuze automatic modulation recognition(AMR)method for low-SNR environments is ***,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2D)fast Fourier transform(FFT)(DR2D)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)***,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCMs),and support vector machines(SVMs)are used for *** DR2D-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical *** trained SVM classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12 d B and above,which represents a good AMR performance of radio fuzes under low SNRs.

关键词： Automatic modulation recognition Adaptive denoising Data rearrangement and the 2D FFT(DR2D) Radio fuze

Influence of Current Density on the Photocatalytic Activity of Nd:TiO_(2) Coatings

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 32-38页

作者：施渊吉 ZHANG Zhen dai Yunzhong LI Jingxiao CHEN Zeyu School of Mechanical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210046China College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China Key Laboratory of Modern Agricultural Equipment and Technology Jiangsu UniversityZhenjiang 212013China

The Nd:TiO_(2 )PEO coatings were formed in a phosphate-based electrolyte with the addition of Nd_(2)O_(3 )under the current density of 150,200,250 and 300 m A/cm^(2).SEM results showed that the micropores decreased on quantity and increased on scale with the increasing current *** results revealed that the roughness of the coatings increased with the increasing current *** and composition analysis showed that the Nd:TiO_(2) coatings were mainly composed of anatase and rutile *** the anatase phase content has reached the maximum value at the current density of 250 m A/cm^(2).XPS results indicated that Ti2p spin-orbit components of the Nd:TiO_(2) coatings are shifted towards higher binding energy,compared with the pure TiO_(2) coating,suggesting that some of the Nd^(3+)ions are combined with TiO_(2) lattice and led to *** test showed that the photocatalytic activity of Nd:TiO_(2) coatings varied in the same pattern with the anatase content variation in Nd:TiO_(2) *** photocatalytic experiment results show that the photocatalytic activity of Nd:TiO_(2) coatings can be greatly enhanced with moderate amount of Nd^(3+).However,excessive amount of Nd^(3+)does not have an effective impact on the photoctalytic activity improvement.

关键词： PEO current density AFM XPS Nd:TiO_(2) photocatalytic

The Influence of Different Solar System Planetary Ephemerides on Pulsar Timing

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Research in Astronomy and Astrophysics 2024年第8期24卷 85-99页

作者： Jian-Peng dai Wei Han Na Wang School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China

Pulsar timing offers a comprehensive avenue for exploring diverse topics in physics and *** solar system planetary ephemeris is crucial for pulsar timing as it provides the positions and velocities of solar system planets including the ***,it is inevitable that inherent inconsistencies exist in these *** between various ephemerides can significantly impact pulsar timing and parameter ***,pulsar timing highly depends on the JPL DE ephemeris,for instance,the Pulsar Timing Array data analysis predominantly utilizes *** this study,we examine inconsistencies across various ephemeris series,including JPL DE,EPM,and ***,discrepancies emerge particularly between the current ephemeris DE436 and the earliest released ephemeris DE200,as well as the most recent ephemerides,e.g.,DE440,INPOP21A,and *** detailed analysis of the effects of ephemeris on geometric correction procedures for the conversion of measured topocentric times of arrival is presented in this *** researches reveal that variations in the Roemer delays across different ephemerides lead to distinct *** timing residuals and the fact that these discrepancies can be readily incorporated into the subsequent pulsar parameters,leading to inconsistent fitting estimates,suggest that the influence of errors in the ephemeris on the timing process might currently be underappreciated.

关键词： (stars)pulsars general-Planetary Systems-time-ephemerides

A Denoiser for Correlated Noise Channel Decoding: Gated-Neural Network

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China Communications 2024年第2期21卷 122-128页

作者： Xiao Li Ling Zhao Zhen dai Yonggang Lei School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Beijing Institute of Tracking and Telecommunications Technology BITTT

This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to transform the correlated noise into white noise, setting up the optimal condition for a standard BP decoder that takes the output from the NN. A gate-controlled neuron is used to regulate information flow and an optional operation—slicing is adopted to reduce parameters and lower training complexity. Simulation results show that SGCNN-BP has much better performance(with the largest gap being 5dB improvement) than a single BP decoder and achieves a nearly 1dB improvement compared to Fully Convolutional Networks(FCN).

关键词： belief propagation channel decoding correlated noise neural network