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.

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.

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.

Low-loss chip-scale programmable silicon photonic processor

Chip-scale programmable optical signal processors are often used to flexibly manipulate the optical signals for satisfying the demands in various applications,such as lidar,radar,and artificial intelligence.Silicon photonics has unique advantages of ultra-high integration density as well as CMOS compatibility,and thus makes it possible to develop large-scale programmable optical signal processors.The challenge is the high silicon waveguides propagation losses and the high calibration complexity for all tuning elements due to the random phase errors.In this paper,we propose and demonstrate a programmable silicon photonic processor for the first time by introducing low-loss multimode photonic waveguide spirals and low-random-phase-error Mach-Zehnder switches.The present chip-scale programmable silicon photonic processor comprises a 1×4 variable power splitter based on cascaded Mach-Zehnder couplers(MZCs),four Ge/Si photodetectors,four channels of thermally-tunable optical delaylines.Each channel consists of a continuously-tuning phase shifter based on a waveguide spiral with a micro-heater and a digitally-tuning delayline realized with cascaded waveguide-spiral delaylines and MZSs for 5.68 ps time-delay step.Particularly,these waveguide spirals used here are designed to be as wide as 2μm,enabling an ultralow propagation loss of 0.28 dB/cm.Meanwhile,these MZCs and MZSs are designed with 2-μm-wide arm waveguides,and thus the random phase errors in the MZC/MZS arms are negligible,in which case the calibration for these MZSs/MZCs becomes easy and furthermore the power consumption for compensating the phase errors can be reduced greatly.Finally,this programmable silicon photonic processor is demonstrated successfully to verify a number of distinctively different functionalities,including tunable time-delay,microwave photonic beamforming,arbitrary optical signal filtering,and arbitrary waveform generation.

Programmable Logic Controller Block Monitoring System for Memory Attack Defense in Industrial Control Systems

Cyberattacks targeting industrial control systems(ICS)are becoming more sophisticated and advanced than in the past.A programmable logic controller(PLC),a core component of ICS,controls and monitors sensors and actuators in the field.However,PLC has memory attack threats such as program injection and manipulation,which has long been a major target for attackers,and it is important to detect these attacks for ICS security.To detect PLC memory attacks,a security system is required to acquire and monitor PLC memory directly.In addition,the performance impact of the security system on the PLC makes it difficult to apply to the ICS.To address these challenges,this paper proposes a system to detect PLC memory attacks by continuously acquiring and monitoring PLC memory.The proposed system detects PLC memory attacks by acquiring the program blocks and block information directly from the same layer as the PLC and then comparing them in bytes with previous data.Experiments with Siemens S7-300 and S7-400 PLC were conducted to evaluate the PLC memory detection performance and performance impact on PLC.The experimental results demonstrate that the proposed system detects all malicious organization block(OB)injection and data block(DB)manipulation,and the increment of PLC cycle time,the impact on PLC performance,was less than 1 ms.The proposed system detects PLC memory attacks with a simpler detection method than earlier studies.Furthermore,the proposed system can be applied to ICS with a small performance impact on PLC.

High-Bandwidth,Low-Power CMOS Transistor Based CAB for Field Programmable Analog Array

This article presents an integrated current mode configurable analog block(CAB)system for field-programmable analog array(FPAA).The proposed architecture is based on the complementary metal-oxide semiconductor(CMOS)transistor level design where MOSFET transistors operating in the saturation region are adopted.The proposed CAB architecture is designed to implement six of thewidely used current mode operations in analog processing systems:addition,subtraction,integration,multiplication,division,and pass operation.The functionality of the proposed CAB is demonstrated through these six operations,where each operation is chosen based on the user’s selection in the CAB interface system.The architecture of the CAB system proposes an optimized way of designing and integrating only three functional cells with the interface circuitry to achieve the six operations.Furthermore,optimized programming and digital tuning circuitry are implemented in the architecture to control and interface with the functional cells.Moreover,these designed programming and tuning circuitries play an essential role in optimizing the performance of the proposed design.Simulation of the proposed CMOS Transistor Based CAB system is carried out using Tanner EDA Tools in 0.35μm standard CMOS technology.The design uses a±1.5 V power supply and results in maximum 3 dB bandwidth of 34.9 MHz and an approximate size of 0.0537 mm2.This demonstrates the advantages of the design over the current state-of-the-art designs presented for comparison in this article.Consequently,the proposed design has a clear aspect of simplicity,low power consumption,and high bandwidth operation,which makes it a suitable candidate for mobile telecommunications applications.

基于5G多接入边缘计算的云化PLC系统架构设计与应用

随着工业控制系统对柔性化、扁平化的要求不断提升,以PLC为构建基础的传统工业控制网络在大规模接入、算力提升和部署灵活性方面均受到限制.针对这些问题,融合5G网络和边缘计算技术,设计了基于5G多接入边缘计算的云化PLC系统架构,阐述了该架构的运行机制和所涉及的关键技术;在此基础上,进行PLC系统的云化部署和调试,实现了工业现场、企业数据中心、5G网络和边缘网络的集成;最后,通过在某汽车制造公司产线改造过程中的应用,验证了所提架构的有效性.

2011—2020年四川省实施结核病防治规划的卫生经济学评价

目的:评估2011—2020年四川省结核病防治经费投入产生的社会效益,为制定新时期中长期发展规划提供参考依据。方法:采用回顾性研究方法,从“结核病管理信息系统”和“传染病监测”系统中收集四川省2011—2020年(“十二五”和“十三五”期间)涂阳肺结核患者治疗转归情况和肺结核患者劳动人口比例,结合四川省统计年鉴和全国结核病防治规划终期评估规划自评调查表等获取经费资料和人均国内生产总值(GDP),采用卫生经济学中常用的成本-效果、成本-效用、成本-效益等3种分析方法估算10年间结核病防治经费投入的社会效果、社会效用和社会效益,并对比分析“十二五”和“十三五”期间的估算结果。结果:2011—2020年,四川省共投入结核病防治经费76032.60万元,成功治疗涂阳肺结核患者160167例,避免了696899名健康人受到传染,挽救了1155277个伤残调整寿命年(disability adjusted life year,DALY),为社会节约医疗费用6.05亿元,挽回社会经济损失约370.32亿元。每投入1091.01元即可避免1名健康人被传染,每投入658.13元即可挽回1个DALY,每投入1元即可产生49.50元的社会经济效益。“十三五”期间带来的总社会效益(209.22亿元)较“十二五”期间(167.14亿元)增长了25.18%[(209.22-167.14)/167.14],但政府每投入1元的结核病防治经费产生的社会效益(47.56元)较“十二五”期间(52.17元)减少了4.61元。结论:2011—2020年间各级政府和国际项目对四川省结核病防控工作投入的经费产生了较好的社会效果、效用和效益。建议在保持目前经费投入力度的基础上,各级政府进一步加大投入,尤其对病原学阳性肺结核患者的发现和治疗管理力度,以期产生更高的社会效益。

ChatGPT对程序员职业的双重影响

ChatGPT的诞生开启了一场波及各行业的技术革命,人工智能在机械性的工作中展示了巨大的潜能,以至于威胁到一些工作岗位的存续,也引发了各行各业和学者们的热烈讨论。软件开发者--—大众口中的程序员,正站在这场技术革命的十字路口,ChatGPT得天独厚的能力既完美地匹配了程序员的工作,同时也威胁到本属于人类的工作岗位。但是这些威胁并非来自技术本身,而是技术的所有者在规范不健全的当下,对他人权利的侵犯。以ChatGPT为代表的人工智能技术不会夺走全部人类的工作,而是会对这些工作加以改变、改善,然而这一切的前提是对人工智能的发展进行正确的引导和规范。如何提升对这种尖端技术的监管能力,如何在发展技术的同时保障人们的权利,将是决定人工智能未来的关键。

基于PLC技术的联合收割机电气控制系统设计

以联合收割机电气控制系统为研究对象,利用可编程控制器(PLC)对联合收割机电气控制系统进行改进,以提高联合收割机运行效率和可靠性。通过对联合收割机的工作原理和液压作动系统进行分析,基于可编程控制器(PLC)进行联合收割机电气系统整体设计,并对电气系统的运行效果进行测试分析。试验结果表明:系统运行可靠,能够获得良好的收割效果,可将收割损失率控制在2%以内,验证了系统运行过程稳定性。

碳中和目标下全球清洁能源消纳的风险识别与规避路径研究

加快向清洁能源转型是二十一世纪的全球目标,在碳中和目标约束下,清洁能源消纳的机遇与挑战并存。本文聚焦不同类别的清洁能源消纳风险,对此进行识别并讨论其风险规避路径。通过深入分析极端天气风险、资源分布的均衡性、消纳技术的特点与应用、政策不确定性、市场及投资环境等情况,发现清洁能源消纳面临多维度、强交叉性风险。鉴于此,提出一套针对性的综合策略,从而促进清洁能源的稳健发展并加速其全球化消纳,包括强化国际合作、选择消纳技术演进路径、加强跨区域政策及监管,构建灵活高效的能源市场等。通过这些策略,旨在为实现清洁能源的广泛应用与可持续消纳提供实用路径,进而支持全球碳中和目标的达成。

高校数控铣床实训过程中的问题与解决方案研究

《数控技能实训》是高等学校本科机械类专业一门重要的专业基础课程。通过本课程学习,使学生初步掌握数控加工的基础工艺知识,掌握基本的编程指令,具备数控车床、数控铣床、数控加工中心、特种加工机床的程序编制能力,并能独立完成简单零件的加工工艺设计及加工,为后继课程的学习打好基础。但目前各高校在数控铣床培训方面还存在各种各样的问题,需要不断的提出探索与研究,本文通过阐述数控技能实训过程中出现的问题,提出了相对应的解决方案。

基于PLC反渗透海水淡化控制系统的设计与开发

针对反渗透海水淡化系统工艺复杂、运维繁琐、对操作人员专业技能要求高的特点,研发了一套反渗透海水淡化控制系统。详细研究整个工艺系统中预处理、反渗透等关键工艺环节的原理及自动控制过程。从系统的硬件设计和软件开发两个方面进行详细阐述。硬件设计方面,根据装置规模和控制需求完成控制系统设备选型。软件开发方面,完成控制器及人机交互界面多套软件的开发。该系统成功应用于高校反渗透海水淡化教学实践课。应用结果表明:该系统设计合理、操作界面简洁方便,在稳定安全运行的同时可实现教学培训、故障处理等目的。该系统在提高海水淡化操作人员专业技能的同时,也对高校创新其他专业的实操培训课程提供了借鉴和技术支撑。

载人离心机预编程过载曲线设计及模拟算法

载人离心机通过三自由度旋转运动进行持续性过载模拟,广泛应用于飞行员过载耐力训练以及航空医学研究等,载人离心机预编程过载曲线模拟精度直接影响训练、研究效果。主要针对载人离心机预编程过载曲线设计及过载模拟算法开展研究,建立载人离心机线性过载变化率曲线和非线性过载变化率曲线设计模型,在此基础上建立过载模拟算法,针对下降段存在的曲线可能无解的问题,提出基于曲线重构的过载模拟算法。通过仿真分析对过载曲线设计方法及模拟算法进行测试,结果表明目标模拟与模拟过载匹配性较高,具有较好的准确性和实用性。

北京市3岁前儿童非免疫规划疫苗接种状况与趋势研究

目的了解北京市3岁前儿童非免疫规划(non-expanded programme on immunization,non-EPI)疫苗接种水平和变化趋势,为加强对非EPI疫苗管理提供参考。方法2023年9月1日,采用系统抽样方法随机抽取北京市免疫规划信息管理系统中2011、2014、2017和2020年的8月份出生的所有儿童个案,分析各年份抽样儿童3岁前接种非EPI疫苗的种类及户籍分布、首剂接种比例、全程免疫完成比例及其变化趋势。结果研究对象共108210名。非EPI疫苗总剂次分别为88019、109442、104451和130501剂次。研究对象3岁前水痘疫苗、肠道病毒71型灭活疫苗(EV71疫苗)和吸附无细胞百白破灭活脊髓灰质炎和b型流感嗜血杆菌(结合)联合疫苗(DTaP-IPV-Hib五联疫苗)首剂接种比例均逐年增加,由最初的<10%分别增加至82.20%、61.07%和39.20%;2020年研究对象中,接种总剂次居前5位的非免疫规划疫苗是13价肺炎疫苗、DTaP-IPV-Hib五联疫苗、EV71疫苗、5价轮状病毒疫苗和水痘疫苗,首剂接种比例分别为48.30%、39.20%、61.07%、30.58%和82.20%,京籍儿童均高于非京籍儿童(P<0.05);3岁前DTaP-IPV-Hib五联疫苗、EV71疫苗和5价轮状病毒疫苗在接种首剂后的多剂次疫苗的全程免疫完成比例分别为92.26%、96.56%和94.37%,京籍儿童均高于非京籍儿童(P<0.05)。结论北京市3岁前儿童非EPI疫苗接种数量和新疫苗种类不断增加,全程接种依从性较高。而在非EPI疫苗的首剂接种比例和非京籍儿童中均需进一步提高。建议开展相关影响因素研究,加强非免疫规划疫苗的技术指导,进一步提高全市非免疫规划疫苗接种数量和质量。

曲靖非相干散射雷达观测研究进展与展望

本文介绍了我国曲靖非相干散射雷达的主要技术方案,结合实测数据分析表明该雷达具备了电离层电子密度与等离子体温度观测、空间碎片凝视探测与月球二维成像探测等能力,可用于研究电离层F层气候学特征、电子密度暴时变化与异常增强等天气事件、E-F谷区结构与变化、约3 cm以上尺寸空间碎片的分布特征与模型、月球不同区域的散射回波特性等.下一步将重点开展低电离层与北驼峰结构及演化过程、电离层暴时与扰动特性观测.

儿科医师转岗培训满意度调查研究

目的调查儿科医师转岗培训满意度,并探讨存在的问题和影响因素,为进一步完善儿科医师转岗培训制度和提高培训质量提供参考。方法采用自制满意度调查量表对2020年11月—2021年11月在湖南省人民医院参加儿科医师转岗培训的81名学员进行转岗医师培训满意度调查。结果81名学员来自湖南省14个地州市,其中来自县市级医疗机构62名、社区医院及乡镇卫生院19名,参加培训的学员77.8%为女性,年龄主要分布在>30~40岁,87.7%的学员具有本科学历,42.0%的学员已取得中级及以上职称。儿科转岗医师对转岗培训的总体满意度评分为(3.72±0.32)分,对理论培训内容的评分最高[(4.02±0.59)分],对临床带教实施的评分最低[(3.44±0.78)分]。>30~40岁年龄段和中高级职称学员的总体满意度、理论培训内容、临床带教实施维度评分高于其他年龄段和职称学员,差异有统计学意义(P<0.05)。结论儿科转岗医师对转岗培训的总体情况满意度较高,但在临床带教实施、临床技能培训、教学活动实施、培训管理方面还需加强,轮转培训方案也需根据学员情况进行调整。

原核Argonaute的应用研究进展

原核生物Argonautes(pAgos)是参与细胞防御外来DNA入侵的可编程核酸酶。在体外,pAgos可以结合小的单链核酸(ssDNA/ssRNA)向导来识别和切割互补DNA/RNA。在体内,pAgos优先靶向多拷贝遗传元件、噬菌体和质粒,从而抑制入侵核酸的扩增和噬菌体感染。pAgos作为一类新兴的可编程核酸酶,比目前应用最为广泛的CRISPR-Cas系统更具灵活性,在生物技术方面展现出巨大的潜力。早期的研究聚焦于嗜热的pAgo,目前基于嗜热pAgos的主要应用包括分子诊断和体外DNA组装。为了推进基于Ago的体内生物技术,如基因编辑的应用,研究人员的焦点逐渐转移到中温生物来源的pAgos,虽然目前pAgos还未实现基因组编辑,但是随着越来越多的pAgo被发掘以及研究人员对pAgos催化机制的深入研究,有望开发基于pAgos的下一代基因编辑技术。本文总结了已知代表性pAgos和基于pAgos发展的生物技术,并简要分析了pAgos在原核生物和真核生物体内应用面临的挑战和可能的应对策略。

面向学科交叉融合的综合性实训教学装置设计与教学实践

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