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Journal of Genetics and Genomics 2024年第1期51卷 105-108页

作者： Tianyu Lei Yue Chang Chao Yao Hong Zhang college of Ecology Lanzhou UniversityLanzhouGansu 730000China Cuiying honors college Lanzhou UniversityLanzhouGansu 730000China

Ribosome profiling(Ribo-Seg)enables genome-wide survey of translational activities at nucleotide resolution by enriching and sequencing ribosome-protected fragments(RPFs)in the cell(Ingolia et al.,2009).Based on the characteristic distribution of RPFs in Ribo-Seq,such as enrichment in open reading frames(ORFs)and three-nucleotide periodicity,many computational methods have been developed to detect translated ORFs from Ribo-Seq data(Wang et al.,2020a).

关键词： translated enable canonical

Monocular Distance Estimated Based on PTZ Camera

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Computers, Materials & Continua 2024年第5期79卷 3417-3433页

作者： Qirui Zhong Xiaogang Cheng Yuxin Song Han Wang Bell honors School Nanjing University of Posts and Telecommunications Nanjing210003China college of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing210003China college of Automation and college of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing210003China

This paper introduces an intelligent computational approach for extracting salient objects fromimages and estimatingtheir distance information with PTZ (Pan-Tilt-Zoom) cameras. PTZ cameras have found wide applications innumerous public places, serving various purposes such as public securitymanagement, natural disastermonitoring,and crisis alarms, particularly with the rapid development of Artificial Intelligence and global infrastructuralprojects. In this paper, we combine Gauss optical principles with the PTZ camera’s capabilities of horizontal andpitch rotation, as well as optical zoom, to estimate the distance of the object.We present a novel monocular objectdistance estimation model based on the Focal Length-Target Pixel Size (FLTPS) relationship, achieving an accuracyrate of over 95% for objects within a 5 km range. The salient object extraction is achieved through a simplifiedconvolution kernel and the utilization of the object’s RGB features, which offer significantly faster computingspeeds compared to Convolutional Neural Networks (CNNs). Additionally, we introduce the dark channel beforethe fog removal algorithm, resulting in a 20 dB increase in image definition, which significantly benefits distanceestimation. Our system offers the advantages of stability and low device load, making it an asset for public securityaffairs and providing a reference point for future developments in surveillance hardware.

关键词： Public security location information PTZ camera image processing

Mechanical Janus lattice with plug-switch orientation

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 23-26页

作者： Yupei Zhang Jiawei Zhong Zhengcai Zhao Ruiyu Bai Yanqi Yin Yang Yu Bo Li State Key Laboratory for Manufacturing System EngineeringShaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Qian Xuesen honors college Xi’an Jiaotong UniversityXi’an 710049China

In recent years,materials with asymmetric mechanical response properties(mechanical Janus materials)have been found possess numerous potential applications,i.***.shock absorption and vibration isolation.In this study,we propose a novel mechanical Janus lattice whose asymmetric mechanical response can be switched in orientation by a plug.Through finite element analysis and experimental verification,this lattice exhibits asymmetric displacement responses to symmetric forces.Furthermore,with such a plug structure inside,individual lattices can switch the orientation of asymmetry and thus achieve reprogrammable design of a mechanical structure with chained lattices.The reprogrammable asymmetry of this material will offer multiple functions in design of mechanical metamaterials.

关键词： Janus Non-reciprocity Programmability Mechanical metamaterial

Design of tightly linked dual ring antenna and imaging of magnetic field distribution using a diamond fiber probe

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Chinese Physics B 2024年第2期33卷 347-352页

作者：叶青云薛雅文何飞越赵旭彤卞雨辰卢文韬王金旭陈鸿浩夏圣开曾明菁杜关祥 college of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China college of Science Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023China Bell honors School Nanjing University of Posts and TelecommunicationsNanjing 210023China

A tightly linked dual ring antenna is designed,and it is specifically tailored for uniformly coupling the microwave magnetic field to the nitrogen-vacancy(NV)center.The designed antenna operates at a center frequency of about 2.87 GHz,with a bandwidth of around 200 MHz,allowing it to address multiple resonance peaks in the optically detected magnetic resonance(ODMR)spectrum in an external magnetic field.Moreover,the antenna generates a fairly uniform magnetic field in a range with a radius of 0.75 mm.High resolution imaging of the magnetic field distribution on the surface of the antenna is conducted by using a fiber diamond probe.We also investigate the effect of magnetic field uniformity on the linewidth of ODMR,so as to provide insights into reducing the inhomogeneous broadening of ODMR.

关键词： nitrogen vacancy(NV) microwave(MW)imaging inhomogeneous broadening

High-resolution imaging of magnetic fields of banknote anti-counterfeiting strip using fiber diamond probe

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Chinese Physics B 2024年第4期33卷 720-727页

作者：赵旭彤何飞越薛雅文马文豪殷筱晗夏圣开曾明菁杜关祥 college of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China college of Science Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023China Bell honors School Nanjing University of Posts and TelecommunicationsNanjing 210023China

Counterfeiting of modern banknotes poses a significant challenge,prompting the use of various preventive measures.One such measure is the magnetic anti-counterfeiting strip.However,due to its inherent weak magnetic properties,visualizing its magnetic distribution has been a longstanding challenge.In this work,we introduce an innovative method by using a fiber optic diamond probe,a highly sensitive quantum sensor designed specifically for detecting extremely weak magnetic fields.We employ this probe to achieve high-resolution imaging of the magnetic fields associated with the RMB 50denomination anti-counterfeiting strip.Additionally,we conduct computer simulations by using COMSOL Multiphysics software to deduce the potential geometric characteristics and material composition of the magnetic region within the anti-counterfeiting strip.The findings and method presented in this study hold broader significance,extending the RMB 50 denomination to various denominations of the Chinese currency and other items that employ magnetic anti-counterfeiting strips.These advances have the potential to significantly improve and promote security measures in order to prevent the banknotes from being counterfeited.

关键词： banknote anti-counterfeiting strip nitrogen-vacancy(NV)centers magnetic field imaging numerical simulation

Electrical uniformity analyses on 12-inch Si-based Hf0.5Zr0.5O2 ferroelectric capacitor devices by atomic layer deposition

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Progress in Natural Science:Materials International 2024年第3期34卷 598-605页

作者： Wen-Juan Ding Yu Liu Zhi-Qiang Xiao Li Gao Yu-Chen Li Lin Zhu Xiang Li Wei-Min Li Shuang Chen Ai-Dong Li National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced MicrostructuresNanjing University Jiangsu Leadmicro Nano-Technology Co. Ltd. Semiconductor Manufacturing North China Corp. Kuang Yaming honors School Nanjing University

The study on the uniformity of electrical performance of large wafer-scale Hf0.5Zr0.5O2（HZO） ferroelectric capacitors is still lacking yet now. In this work, TiN/HZO/TiN metal-ferroelectric-metal（MFM） devices on 12-inch silicon wafers have been fabricated by thermal atomic layer deposition. The correlation of thickness uniformity with device-to-device variation of electrical properties and yield of the 12-inch MFM system was investigated. It was found that the uniformity of ferroelectric properties is closely related to the variation of HZO thickness of the MFM system, the concentration of oxygen vacancies in the micro-region of the HZO film, and the ferroelectric phase micro-distribution on 12-inch Si wafer. This work provides some important information for the performance optimization of HfO2-based ferroelectric random access memories.

关键词： 12-Inch Si wafer Atomic layer deposition Electrical uniformity Ferroelectric random access memory Hf0.5Zr0.5O2 ferroelectric thin film

Tunable dispersion relations manipulated by strain in skyrmion-based magnonic crystals

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Chinese Physics B 2024年第1期33卷 692-696页

作者：金兆年何宣霖于超方贺男陈琳陶志阔 Bell honors School Nanjing University of Posts and TelecommunicationsNanjing 210003China college of Electronic and Optical Engineering&college of Flexible Electronics Nanjing University of Posts and TelecommunicationsNanjing 210003China

We theoretically investigate the propagation characteristics of spin waves in skyrmion-based magnonic crystals. It is found that the dispersion relation can be manipulated by strains through magneto-elastic coupling. Especially, the allowed bands and forbidden bands in dispersion relations shift to higher frequency with strain changing from compressive to tensile,while shifting to lower frequency with strain changing from tensile to compressive. We also confirm that the spin wave with specific frequency can pass the magnonic crystal or be blocked by tuning the strains. The result provides an advanced platform for studying the tunable skyrmion-based spin wave devices.

关键词： skyrmion magnonic crystal spin wave dispersion relation

Collision off-axis position dependence of relativistic nonlinear Thomson inverse scattering of an excited electron in a tightly focused circular polarized laser pulse

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Chinese Physics B 2024年第1期33卷 344-354页

作者：王禹博杨青屿常一凡林宗熠田友伟 Bell honors School Nanjing University of Posts and TelecommunicationsNanjing 210023China college of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China

This paper presents a novel view of the impact of electron collision off-axis positions on the dynamic properties and relativistic nonlinear Thomson inverse scattering of excited electrons within tightly focused, circularly polarized laser pulses of varying intensities. We examine the effects of the transverse ponderomotive force, specifically how the deviation angle and speed of electron motion are affected by the initial off-axis position of the electron and the peak amplitude of the laser pulse. When the laser pulse intensity is low, an increase in the electron's initial off-axis distance results in reduced spatial radiation power, improved collimation, super-continuum phenomena generation, red-shifting of the spectrum's harmonic peak, and significant symmetry in the radiation radial direction. However, in contradiction to conventional understandings,when the laser pulse intensity is relatively high, the properties of the relativistic nonlinear Thomson inverse scattering of the electron deviate from the central axis, changing direction in opposition to the aforementioned effects. After reaching a peak, these properties then shift again, aligning with the previous direction. The complex interplay of these effects suggests a greater nuance and intricacy in the relationship between laser pulse intensity, electron position, and scattering properties than previously thought.

关键词： relativistic nonlinear Thomson inverse scattering off-axis collision radiation angle distribution tightly focused laser pulse

数据驱动方法揭示单原子掺杂金红石氧化物在甲烷活化过程中的活性位点

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Science China Materials 2024年第4期67卷 1231-1242页

作者：卫奋飞葛冰青董佩佩万强胡茜茜林森 college of Chemistry Fuzhou UniversityFuzhou 350002China Institute(college)of Integrative Medicine Dalian Medical UniversityDalian 116044China Department of Chemistry and Materials Science Zhejiang Normal UniversityJinhua 321004China Kuang Yaming honors School Nanjing UniversityNanjing 210023China

金属氧化物通常用于甲烷的活化和转化,但总是受到过度氧化的影响.引入单原子是解决这一难题的一种有吸引力的方法,但掺杂单原子的实际作用仍存在争议.因此,开发性能描述符来预测掺杂表面上不同位点之间的反应性至关重要.在这项工作中,... 详细信息

金属氧化物通常用于甲烷的活化和转化,但总是受到过度氧化的影响.引入单原子是解决这一难题的一种有吸引力的方法,但掺杂单原子的实际作用仍存在争议.因此,开发性能描述符来预测掺杂表面上不同位点之间的反应性至关重要.在这项工作中,采用单原子(D_(guest),D=Ti,V,Cr,Mn,Nb,Mo,Ru,Rh,Ta,Re,Os,Ir,Pt,Si,Ge和Sn)掺杂的金红石型金属氧化物(MO_(2),M=Ru,Rh,Ir,Pt,Mo)作为模型催化剂,利用密度泛函理论计算和数据驱动方法研究了甲烷在不同表面位点上的活化情况,并阐明了此类掺杂表面的实际活性位点.利用机器学习方法,从特征组合描述符的大空间中获得了多维描述符,从而可以统一预测D_(guest)和M_(host)上活化CH_(4)的能垒,而不受过渡态计算的影响.最后,MO_(2)上客体位点对选择性氧化的调节作用得到了证实.我们的工作证明了掺杂剂在催化过程中的复杂作用,所开发的描述符有助于确定活化能,为基于金红石氧化物的催化剂提供潜在的选择性氧化位点.

关键词：金属氧化物单原子选择性氧化过度氧化特征组合描述符数据驱动方法催化过程

Effect of mixing section configurations on combustion efficiency of Mg-CO_(2)Martian ramjet

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Chinese Journal of Aeronautics 2023年第4期36卷 165-173页

作者： Xu WANG Yanpeng BU Xu XU Qingchun YANG School of Astronautics Beihang UniversityBeijing 100191China shenyuan honors college Beihang UniversityBeijing 100191China

Experiments were conducted to determine the effects of the mixing section configurations on the Mg-CO_(2)Martian ramjet combustion efficiency.It was carried out at a mainstream mass flow rate of 110 g/s and a temperature of 810 K.The chamber pressure was measured under different configurations and Oxidizer to Fuel(O/F)ratios.Results showed that the engine achieved self-sustaining combustion and worked stably during experiments.The pre-combustion chamber is needed to increase the combustion efficiency and promote the full combustion of the powder.After the configuration of the pre-combustion chamber,the best combustion efficiency reached 80%when radial powder injection and lateral carbon dioxide intake were used.In addition,the O/F ratio in the pre-combustion chamber decreased from 0.67 to 0.31,resulting in an 8%increase in the combustion efficiency.It was speculated that different mixing section configurations and the variations in an O/F ratio within the pre-combustion chamber impacted the combustion efficiency and in essence,all affected the flow velocity and residence time of the two-phase flow in the com-bustion chamber.

关键词： Combustion efficiency Magnesium-base fuel Martian ramjet Mars exploration Structural configurations