Multi-stable straw-like carbon nanotubes for mechanical programmability at microscale

Inspired by macroscale 3D pixel mechanical metamaterials and microscale straw-like carbon nanotube,we propose a design of multi-stable straw-like carbon nanotubes(MSCNT)via optimizing the structure of a unit to obtain multiple stable states under dis-placement loading by molecular dynamics.The unit of MSCNT is mirror-symmetrically connected two truncated graphene cones with specific apex angles.By switching the LJ term in AIREBO potential,we verify that the bistability of unit is co-determined by snap-through instability and microscale adhesions.Moreover,we examine the validity of the multi-stability of the unit cells arranged in series and in parallels.Simulation results indicate that the MSCNT can achieve mechanical programmability in microscale,which triggers many potential applications in need of customizing nanos-cale mechanical behaviors.

Mechanical Janus lattice with plug-switch orientation

In recent years,materials with asymmetric mechanical response properties(mechanical Janus materials)have been found possess numerous potential applications,i.e.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.

Digital signal acquisition system for complex nuclear reaction experiments

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control parameters.The proposed digital system can be combined with a conventional analog data acquisition system to provide more flexibility.The performance of the combined system was veri-fied using experimental data.

Recent Advance in Synaptic Plasticity Modulation Techniques for Neuromorphic Applications

Manipulating the expression of synaptic plasticity of neuromorphic devices provides fascinating opportunities to develop hardware platforms for artifi-cial intelligence.However,great efforts have been devoted to exploring biomimetic mechanisms of plasticity simulation in the last few years.Recent progress in various plasticity modulation techniques has pushed the research of synaptic electronics from static plasticity simulation to dynamic plasticity modulation,improving the accuracy of neuromorphic computing and providing strategies for implementing neuromorphic sensing functions.Herein,several fascinating strategies for synap-tic plasticity modulation through chemical techniques,device structure design,and physical signal sensing are reviewed.For chemical techniques,the underly-ing mechanisms for the modification of functional materials were clarified and its effect on the expression of synaptic plasticity was also highlighted.Based on device structure design,the reconfigurable operation of neuromorphic devices was well demonstrated to achieve programmable neuromorphic functions.Besides,integrating the sensory units with neuromorphic processing circuits paved a new way to achieve human-like intelligent perception under the modulation of physical signals such as light,strain,and temperature.Finally,considering that the relevant technology is still in the basic exploration stage,some prospects or development suggestions are put forward to promote the development of neuromorphic devices.

Pixelated non-volatile programmable photonic integrated circuits with 20-level intermediate states

Multi-level programmable photonic integrated circuits(PICs)and optical metasurfaces have gained widespread attention in many fields,such as neuromorphic photonics,opticalcommunications,and quantum information.In this paper,we propose pixelated programmable Si_(3)N_(4)PICs with record-high 20-level intermediate states at 785 nm wavelength.Such flexibility in phase or amplitude modulation is achieved by a programmable Sb_(2)S_(3)matrix,the footprint of whose elements can be as small as 1.2μm,limited only by the optical diffraction limit of anin-house developed pulsed laser writing system.We believe our work lays the foundation for laser-writing ultra-high-level(20 levels and even more)programmable photonic systems and metasurfaces based on phase change materials,which could catalyze diverse applications such as programmable neuromorphic photonics,biosensing,optical computing,photonic quantum computing,and reconfigurable metasurfaces.

Machine learning algorithm partially reconfigured on FPGA for an image edge detection system

Unmanned aerial vehicles(UAVs)have been widely used in military,medical,wireless communications,aerial surveillance,etc.One key topic involving UAVs is pose estimation in autonomous navigation.A standard procedure for this process is to combine inertial navigation system sensor information with the global navigation satellite system(GNSS)signal.However,some factors can interfere with the GNSS signal,such as ionospheric scintillation,jamming,or spoofing.One alternative method to avoid using the GNSS signal is to apply an image processing approach by matching UAV images with georeferenced images.But a high effort is required for image edge extraction.Here a support vector regression(SVR)model is proposed to reduce this computational load and processing time.The dynamic partial reconfiguration(DPR)of part of the SVR datapath is implemented to accelerate the process,reduce the area,and analyze its granularity by increasing the grain size of the reconfigurable region.Results show that the implementation in hardware is 68 times faster than that in software.This architecture with DPR also facilitates the low power consumption of 4 mW,leading to a reduction of 57%than that without DPR.This is also the lowest power consumption in current machine learning hardware implementations.Besides,the circuitry area is 41 times smaller.SVR with Gaussian kernel shows a success rate of 99.18%and minimum square error of 0.0146 for testing with the planning trajectory.This system is useful for adaptive applications where the user/designer can modify/reconfigure the hardware layout during its application,thus contributing to lower power consumption,smaller hardware area,and shorter execution time.

Reconfigurable mechanism-based metamaterials for ternary-coded elastic wave polarizers and programmable refraction control

Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves.However,most of them rely on the resonant structural components,and thus are frequency-dependent and unchangeable.Here,we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic properties.Based on the proposed mechanism-based metamaterial,interesting functionalities,such as ternarycoded elastic wave polarizer and programmable refraction,are demonstrated.Particularly,unique ternary-coded polarizers,with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves,are first achieved.Then,the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction,only-positive refraction,and only-negative refraction.Finally,the wave functions with detailed microstructures are numerically verified.

A novel one-time-programmable memory unit based on Schottky-type p-GaN diode

In this work,a novel one-time-programmable memory unit based on a Schottky-type p-GaN diode is proposed.During the programming process,the junction switches from a high-resistance state to a low-resistance state through Schottky junction breakdown,and the state is permanently preserved.The memory unit features a current ratio of more than 10^(3),a read voltage window of 6 V,a programming time of less than 10^(−4)s,a stability of more than 108 read cycles,and a lifetime of far more than 10 years.Besides,the fabrication of the device is fully compatible with commercial Si-based GaN process platforms,which is of great significance for the realization of low-cost read-only memory in all-GaN integration.

National Social Investment Programmes in Nigeria:A Descriptive Analysis of the Socio-Economic Contributions of N-Power Programme in Benue State

This study analysed the socio-economic contributions of N-Power programme amongst the beneficiaries of the scheme in Benue State.Prior to the introduction of N-Power programme,successive administrations in Nigeria have made concerted efforts towards improving the standard of living of the citizenry through the execution of various welfare or social intervention programmes,but not much successes were recorded.Learning from the mistakes of the past regimes,and by way of deliberate state policy,the Buhari’s government initiated a multi-pronged social investment policy,one of which is the N-power programme that came onboard in 2016,which also doubles as the subject of this study.To achieve the goal of this study,a combination of desktop research and survey design was employed.Questionnaires were administered to 390 respondents through a combination of stratified and random sampling techniques.The results of the survey were matched with that of the secondary data obtained through online websites and other related sources.The result indicated that N-Power made positive contributions to the socio-economic life of the beneficiaries in Benue State:specifically,the scheme contributed in poverty eradication,employment generation,skills acquisitions and capacity building.However,some aspect of our findings revealed that the programme has a number of challenges such as:inadequate cash support,delay in monthly cash transfer to beneficiaries,distance participants had to move to their work stations,absence of posting in N-Teach scheme,and lack of adequate working tools amongst others.To salvage this problem the paper recommended the following solutions:expansion of the scheme to cover N-Teach and other aspects,increment in the monthly cash transfer to cushion the high rate of inflation,support for the participants/beneficiaries in transportation and logistics,enrolment of more youth into the various schemes,proper monitoring and evaluation of the implementation of the schemes amongst others.

Teaching Reform and Exploration of Practical Courses Based on Programmable Control

As the country continues to promote the development of intelligent manufacturing,all industries are carrying out enterprise automation upgrading,the Pearl River Delta Intelligent Manufacturing Conference held in March 2024 provides a direction guide for each enterprise on how to integrate the intelligent manufacturing technology into each link and provide direction guidance for enterprises to create new models and new business formats.College teachers,in focusing on the teaching process,should closely match the enterprise and social needs and cultivate excellent students.As the core controller of automation control,the application of programmable controllers in teaching is particularly important.In practical classes,by setting progressive difficulty,project guidance,team collaboration,and other links,students can master the automation equipment design of programmable control in repeated practice.

Enhancing Programmable Logic Controller Teaching in Vocational Colleges:Strategies for Deeper Understanding and Practical Application

This paper addresses the problems faced in programmable logic controller(PLC)teaching in vocational colleges and proposes countermeasures to overcome these challenges.The study emphasizes the need for a deeper understanding of fundamental concepts and the integration of practical application in PLC education.It suggests involving students in teacher-led projects to enhance their programming skills and problem-solving skills.Additionally,the paper highlights the importance of interactive learning and collaborative discussions to foster student engagement.Furthermore,it emphasizes the cultivation of innovation consciousness through participation in innovation competitions and projects.The implementation of these strategies has shown positive results in improving learning outcomes and preparing students for careers in automation and control.This research contributes to the development of effective teaching approaches in PLC education in vocational colleges.

大尺寸机载显示模块动态背光控制系统设计

机载大尺寸液晶显示器(liquid crystal display,LCD)显示模块具有亮度高和功耗大的特点。为了降低其动态功耗,介绍了一种用于大尺寸机载显示模块的动态背光控制系统。该系统采用发光二极管(light emitting diode,LED)动态背光控制技术,通过对背光的动态调节,提高动态显示效果和达到节能的目的。对系统的硬件电路和软件设计算法进行了详细的介绍,并进行实验验证。结果表明,该系统能够有效地提高机载显示模块的动态显示效果,并显著降低了动态功耗。

GJB 5000B在FPGA工程中的应用分析

为引入软件工程化管理办法对设计开发实践实施管理,结合GJB 5000B体系要求,对现场可编程逻辑门阵列(Field Programmable Gate Array,FPGA)的设计开发流程和GJB 5000B的工程实践要求进行梳理、比对和分析,并提出一套FPGA开发管理在GJB 5000B推进实践中的实施办法。研究成果可为GJB 5000B在FPGA工程中的应用提供一定参考。

基于数学形态学的红外点目标实时检测算法及其CPLD实现

基于数学形态学提出了一种红外图像序列中点目标的检测算法及其硬件系统的实现 .首先介绍了基于数学形态学的点目标检测算法的基本原理 ,然后根据算法的特点提出了它在CPLD上的并行流水线实现方法 ,最后给出并分析了算法软件和硬件系统的仿真结果 .结果表明该方法可以快速、可靠地检测出低信杂比红外图像序列中的点目标 ,且系统结构简单 ,无需存储器 。

一款基于新型Field Programmable Gate Array芯片的投影仪梯形校正系统研究与实现

投影设备配备的梯形校正普遍存在校正范围小,画面的一些线条和字符边缘会出现毛刺和不平滑现象,矫正效果不理想.如果采用通用的图像处理芯片和复杂的算法,可以解决上述问题,但又会导致成本急剧上升.为了解决上述矛盾,提出一种基于FPGA(Field Programmable Gate Array)芯片的新型梯形校正实现方案,解决了校正范围与锯齿失真的矛盾问题,并为进一步成为芯片级产品铺平了道路.图像处理采用kaiser窗函数和sinc函数相结合的方法进行插值,这样的滤波器改善了旁瓣抑制,具有较好的通带性能.介绍了梯形失真的产生和校正原理,提出了利用FPGA芯片XC3S400作为核心图像处理单元的梯形校正系统的硬件和软件实现,说明了该芯片结构、功能及特性,最后提供了校正的效果图.

基于DSP与FPGA的变流器通用控制平台研究

提出一种基于DSP和现场可编程门阵列(FPGA)双CPU结构的新型变流器控制系统方案,其中DSP完成变流器控制策略的实现,主要包括:最大功率点跟踪、电压电流双闭环控制、低电压穿越控制、通信功能;FPGA完成三相锁相环控制、AD芯片采样控制、SVPWM波形控制、逻辑输出控制以及各类故障信号检测与停机保护功能,并采用了基于WIFI模块的风电故障信息传输系统。以双馈风电变流器为模型,设计了双馈风力发电变流器系统,完成了两电平与三电平SVPWM控制算法的FPGA实现。最后在自主研发的1.5 MW,2 MW双馈式变流器样机与光伏逆变器样机上进行了大量实验和长期的现场试运行,验证了控制系统平台的可行性与实用性。

造纸机PLC程序的结构化设计研究

针对工程实践中造纸机PLC控制程序存在设计效率低、通用性不强等特点,提出运用软件工程方法对其进行标准化设计。通过分析造纸机多分部传动控制的特点,采用结构化方法进行需求分析和程序设计。实践验证,该方法应用在造纸机上是可行的,且能提高程序的设计效率和通用性。软件工程的软件设计方法在工业控制领域的应用具有很好的前景。

SRAM型FPGA单粒子辐照试验系统技术研究

单粒子辐射效应严重制约FPGA的空间应用,为提高FPGA在辐射环境中的可靠性,深入研究抗辐射加固FPGA单粒子效应评估方法,设计优化单粒子效应评估方案,开发相应的评估系统,提出基于SRAM时序修正的码流存储比较技术和基于SelectMAP端口配置回读技术。借助国内高能量大注量率的辐照试验环境,完成FPGA单粒子翻转(SEU)、单粒子闩锁(SEL)和单粒子功能中断(SEFI)等单粒子效应的检测,试验结果表明,该方法可以科学有效地对SRAM型FPGA抗单粒子辐射性能进行评估。

Design and Implementation of an FDP Chip

A novel Fudan programmable logic chip （FDP） was designed and implemented with a SMIC 0. 18μm CMOS logic process. The new 3-LUT based logic cell circuit increases logic density about 11% compared with a traditional 4-input LUT. The unique hierarchy routing fabrics and effective switch box optimize the routing wire segments and make it possible for different lengths to connect directly. The FDP contains 1,600 programmable logic cells, 160 programmable I/O, and 16kbit dual port block RAM. Its die size is 6. 104mm× 6. 620mm, with the package of QFP208. The hardware and software cooperation tests indicate that FDP chip works correctly and efficiently.

Design of Down Scalers in Mixed-Signal GHz Frequency Synthesizer

An optimized method is presented to design the down scalers in a GHz frequency synthesizer. The down scalers are comprised of dual modulus prescaler （DMP） and programmable ＆ pulse swallow divider,different methods of high frequency analog circuit and digital logical synthesis are adopted respectively. Using a DMP high speed, lower jitter and lower power dissipation are obtained,and output frequency of 133.0MHz of the DMP working at divide-by-8 shows an RMS jitter less than 2ps. The flexibility and reusability of the progrs, mmable divider is high;its use could be extended to many complicated frequency synthesizers. By comparison,it is a better design on performance of high-frequency circuit and good design flexibility.