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联合卡尔曼滤波和泰勒残差展开的回声消除方法

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南昌航空大学学报（自然科学版） 2024年第1期38卷 32-42页

作者：李勇孙成立陈飞龙南昌航空大学信息工程学院南昌330063 广州航海学院信息与通信工程学院广州510725

现有基于深度学习的声学回声消除算法主要采用端到端的结构,这种结构使得神经网络模型在设计上的可解释性难以实现。针对这一问题,提出一种联合卡尔曼滤波和泰勒残差展开的回声消除方法,可以为网络结构设计提供很好的可解释性。该方法... 详细信息

现有基于深度学习的声学回声消除算法主要采用端到端的结构,这种结构使得神经网络模型在设计上的可解释性难以实现。针对这一问题,提出一种联合卡尔曼滤波和泰勒残差展开的回声消除方法,可以为网络结构设计提供很好的可解释性。该方法由线性自适应滤波和深度神经网络两部分组成。首先,采用神经卡尔曼滤波(Neural Kalman Filtering,NKF)作为自适应滤波器去除线性噪声,获得目标语音的粗略频谱估计;然后,通过泰勒展开神经网络对粗谱估计的结果进一步处理,以抑制非线性残留回声,并逐步修复目标语音的复数频谱。在泰勒展开神经网络中设计融合不同尺度时频特征的编解码网络用于零阶项估计,构建轻量级高阶项估计网络,并按颗粒度由大到小重建目标语音复数频谱。结果表明,相比现有的主流回声消除方法,本文所提方法的性能有显著提升。双讲情况下,语音质量感知评估(Perceptual Evaluation of Speech Quality,PESQ)和短时客观可懂度(Short-Time Objective Intelligibility,STOI)均有大幅提升;单讲情况下,回声损失增强度量(Echo Return Loss Enhancement,ERLE)达到了56.106的优良表现,相比先进的UNET神经网络方法提高了6.5%。

关键词：回声消除自适应滤波泰勒展开渐进学习神经网络

Pd(I)-catalyzed ring-opening arylation of cyclopropyl-α-aminoamides:Access toα-ketoamide peptidomimetics

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Chinese Chemical Letters 2024年第6期35卷 320-326页

作者： Yue sun liming Yang Yaohang cheng Guanghui An Guangming li School of Chemistry and Materials Science Heilongjiang UniversityHarbin 150080China

We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-*** protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challenging peptide-natural product *** selectivity was achieved by introduction of special unnatural amino acids,which also meets the requisite of bioorthogonal *** investigations reveals a distinct domino radical ring-opening process through Pd(I)catalysis.

关键词： Pd(I)catalysis Ring-opening arylation Domino reactions Oligopeptides Late-stage functionalization

Mechanism of capture section affecting an intake for atmosphere-breathing electric propulsion

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Chinese Journal of Aeronautics 2024年第1期37卷 51-63页

作者： Siyuan ZHANG Jinyuan YANG cheng li Haolin li liwei ZHANG liang DING Anbang sun State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China China Academy of Aerospace Science and Innovation Beijing 100049China

Atmosphere-Breathing Electric Propulsion(ABEP)can compensate for lost momentum of spacecraft operating in Very Low Earth Orbit(VLEO)which has been widely concerned due to its excellent commercial *** is a key technology to improve the capture efficiency of intakes,which collect and compress the atmosphere for *** this paper,the mechanism of the capture section affecting capture efficiency is investigated by Test Particle Monte Carlo(TPMC)simulations with 3D intake *** inner surface smoothness and average collision number are determined to be key factors affecting capture efficiency,and a negative effect growth model is accordingly *** the inner surface smoothness is less than 0.2,the highest capture efficiency and its corresponding average collision number interval are independent of the capture section’s geometry and its mesh *** the inner surface smoothness is higher than 0.2,the capture efficiency will decrease by installing any capture *** on the present results,the manufacturing process and material selection are suggested to be prioritized during the intake geometry design in engineering ***,the highest capture efficiency can be achieved by adjusting the length and mesh size of the capture section.

关键词： Atmosphere-breathing electric propulsion Capture efficiency Capture section Intake Test particle Monte Carlo Very low earth orbit

Recent process developments in beneficiation and metallurgy of rare earths:A review

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Journal of Rare Earths 2024年第4期42卷 629-642页

作者： Shaokai cheng Wenbo li Yuexin Han Yongsheng sun Peng Gao Xiaolong Zhang School of Resources and Civil Engineering Northeastern UniversityShenyang110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang110819China

Rare earth elements(REEs)are irreplaceable materials supporting low-carbon technology and equip-ment,and their commercial demand and strategic position are becoming increasingly *** the continuous depletion of rare earth(RE)resources,developing high-efficiency beneficiation and eco-friendly metallurgical processes has attracted widespread *** paper reviews the major minerals exploited for RE production and their deposits,as well as the beneficiation and metallurgical processes of RE ***,monazite,mixed RE ores,and ion-adsorption clays are the main raw materials in the world to ***-bearing ores(except ion-adsorption minerals)are generally beneficiated by flotation,gravity and magnetic separation *** mainstream metallurgical processes for bastnaesite,monazite and mixed RE concentrates are oxidation roasting-HCl leaching,caustic soda decomposition and high-temperature concentrated sulfuric acid roasting,***-adsorption clays are directly processed by in situ leaching-precipitation/solvent *** achieve the sustainable development of RE resources,it is essential to further explore innovative techniques to achievecomprehensive utilization and cleaner production.

关键词： Rare earths Beneficiation processes Metallurgical processes Cleaner production

Vanadyl Sulfate Based Hole-Transporting Layer Enables Efficient Organic Solar Cells

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Chinese Journal of Chemistry 2024年第14期42卷 1644-1650页

作者： Mengdi li Yuqing sun Yang cheng Chaowei Zhao Jicai Zhang Weiwei li Research Center for Optoelectronic Materials and Devices School of Physical Science and TechnologyGuangxi UniversityNanningGuangxi530004 China Institute of Applied Chemistry Jiangxi Academy of SciencesNanchangJiangxi330096 China Beijing Advanced Innovation Center for Soft Matter Science and Engineering&State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029 China

It remains an urgent task to develop alternative hole-transporting layer(HTL)materials beyond commonly used PEDOT:PSS to increase the shelf-life of organic solar cells(OSCs).Inorganic metal oxide type materials,such as NiO_(x),CoO_(x)and VO_(x),with suitable work functions have attracted numerous research attention *** this work,more abundant and easily accessible oxygenated salt,vanadyl sulfate(VOSO_(4))has been demonstrated to be excellent choice as HTL for *** VOSO_(4)-based HTL can be readily processed by spin-coating from the precursor solution with subsequent thermal annealing and UVO *** a consequence,a high power conversion efficiency(PCE)of 18.72%can be achieved for PM8:L8-BO based OSCs with the VOSO_(4)-based *** transmittance,smooth film surface,suitable energy level and high conductivity were revealed to contribute to the high OSC *** importantly,compared to device with PEDOT:PSS,VOSO_(4)-based OSCs exhibit improved stability when stored in the N_(2)filled glove *** being stored for 600 h,VOSO_(4)-based device can retain 89%of its initial ***,VOSO_(4)can be used as general HTL in PM6:BTP-BO-4Cl and PM6:IT-4F based OSCs,yielding high PCEs of 17.87%and 13.85%,respectively.

关键词： Organic solar cells Semiconductors Hole-transporting layers Vanadyl sulfate Power output Efficiency Vanadium Interfacial modification

Blindness-free beam scanning antenna with array of array architecture: principle,design,and experiment

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Science China(Information Sciences) 2024年第3期67卷 209-224页

作者： Jianxu sun Yujian cheng School of Electronic Science and Engineering University of Electronic Science and Technology of China

This paper presents a 66–76-GHz sparsely-excited phased array antenna with the array of array(Ao A) architecture for eliminating the blindness and suppressing the grating lobe when scanning. For the array antennas printed on the thick dielectric layers with high relative permittivity, scanning blindness appears and seriously impacts the radiation performance. To address this issue, the Ao A topology is developed first. It finds that the scanning blindness appears due to the coupling of the radiating Floquet modes to the non-radiating surface wave(SW) modes. Therefore, the array is divided into two types of domino *** inner-phase distributions are introduced into the domino subarrays to break the one-to-one relationship between the Floquet mode and the SW mode. Then, the blindness inside ±60° scanning volume is eliminated by the aperiodic subarrays. Meanwhile, the aperiodic inner-phase distributions enhance the aperiodicity of the array and contribute to suppressing the grating lobe when scanning. Next, the meta-surface-based dipole with the shorted post is chosen as the unit cell for the proposed aperiodic array. Based on these methods,the array achieves the wide-scanning performance of ±60° in the E-plane and ±30° in the H-plane, without the blindness and the grating lobe. Finally, the 16×16 array is built and simulated with the dimension of32 mm × 32 mm. At the highest operating frequency, the simulated gains are 28.42, 25.17, and 24.01 d Bi when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. Compared to the ideal gain, it shows that the simulated radiation efficiency is about 84.13%, 62.08%, and 35.23% when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. The worst transmission coefficient, i.e., the worst isolation, is-11.97 d B between the central element and its two adjacent elements in the E-plane. The array prototypes are fabricated, and the experiments are carried out to ver

关键词： 6G communication systems phased array AoA aperiodic subarray wideband wide-scanning surface-wave scanning blindness grating lobe

Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

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Petroleum Science 2024年第1期21卷 621-640页

作者： Xue-Qiang Zhang Qing-lin cheng Wei sun Yi Zhao Zhi-Min li Key Lab of Ministry of Education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum UniversityDaqing163318HeilongjiangChina China Petroleum Pipeline Material and Equipment Co. LtdLangfang065000HebeiChina Research Institute of Petroleum Engineering and Technology Sinopec Northwest Oilfield CompanyUrumqi830011XinjiangChina

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex *** is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency *** this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is *** with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation *** comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are *** the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy *** entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their ***,the weak links in energy utilization are identified,and energy conservation and consumption reduction are *** above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

关键词： Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction

BrrTCP4b interacts with BrrTTG1 to suppress the development of trichomes in Brassica rapa var. rapa

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Plant Diversity 2024年第3期46卷 416-420页

作者： cheng li li Zhang Hefan li Yuanwen Duan Xuemei Wen Yongping Yang Xudong sun The Germplasm Bank of Wild Species Yunnan Key Laboratory of Crop Wild Relatives OmicsInstitute of Tibetan Plateau Research at KunmingKunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences BeijingChina Tibet Plateau Institute of Biology Lhasa 850001TibetChina

The number of trichomes significantly increased in CRISPR/Cas9-edited BrrTCP4b turnip(Brassica rapa ***)***,the underlying molecular mechanism remains to be *** this study,we performed the Y2H screen using BrrTCP4b as the bait,which unveiled an interaction between BrrTCP4b and BrrTTG1,a pivotal WD40-repeat protein transcription factor in the MYB-bHLH-WD40(MBW)*** physical interaction was further validated through bimolecular luciferase complementation and ***,it was found that the interaction between BrrTCP4b and BrrTTG1 could inhibit the activity of MBW complex,resulting in decreased expression of BrrGL2,a positive regulator of trichomes *** contrast,AtTCP4 is known to regulate trichomes development by interacting with AtGL3 in Arabidopsis ***,this study revealed that BrrTCP4b is involved in trichome development by interacting with BrrTTG1 in turnip,indicating a divergence from the mechanisms observed in model plant *** findings contribute to our understanding of the regulatory mechanisms governing trichome development in the non-model plants turnip.

关键词： TCP transcription factor MBW complex Trichome development Turnip

Strong,tough,and thermally conductive nacre-inspired boron nitride nanosheet/epoxy layered nanocomposites

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Nano Research 2024年第2期17卷 820-828页

作者： Huagao Wang Rongjian Lu Lei li cheng liang Jia Yan Rui liang Guoxing sun Lei Jiang Qunfeng cheng School of Chemistry Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of EducationBeihang UniversityBeijing 100191China School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhou 215123China Department of Stomatology Fifth Medical CenterChinese PLA General HospitalBeijing 100039China Department of Engineering Science Faculty of Innovation EngineeringMacao University of Science and TechnologyAvenida Wai LongTaipaMacao 999078 China Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoAvenida da UniversidadeTaipaMacao 999078China Institute of Energy Materials Science(IEMS) University of Shanghai for Science and TechnologyShanghai 200093China

Thermally conductive polymer nanocomposites integrated with lightweight,excellent flexural strength,and high fracture toughness(KIc)would be of great use in many ***,achieving all of these properties simultaneously remains a great *** by natural nacre,here we demonstrate a lightweight,strong,tough,and thermally conductive boron nitride nanosheet/epoxy layered(BNNEL)*** of the layered structure and enhancing the interfacial interactions through hydrogen bonding and Si–O–B covalent bonding,the resulting nacre-inspired BNNEL nanocomposites show high fracture toughness of~4.22 MPa·m^(1/2),which is 7 folds as high as pure ***,the BNNEL nanocomposites demonstrate sufficient flexural strength(~168.90 MPa,comparable to epoxy resin),while also being lightweight(~1.23 g/cm^(3)).Additionally,the BNNEL nanocomposites display a thermal conductivity(κ)of~0.47 W/(m·K)at low boron nitride nanosheet loading of 2.08 vol.%,which is 2.7 times higher than that of pure epoxy *** developed nacre-inspired strategy of layered structure design and interfacial enhancement provides an avenue for fabricating high mechanical properties and thermally conductive polymer nanocomposites.

关键词： nacre-inspiration nanocomposites flexural strength fracture toughness(KIc) thermal conductivity