Novel fabrication techniques for ultra-thin silicon based flexible electronics

Flexible electronics offer a multitude of advantages,such as flexibility,lightweight property,portability,and high durability.These unique properties allow for seamless applications to curved and soft surfaces,leading to extensive utilization across a wide range of fields in consumer electronics.These applications,for example,span integrated circuits,solar cells,batteries,wearable devices,bio-implants,soft robotics,and biomimetic applications.Recently,flexible electronic devices have been developed using a variety of materials such as organic,carbon-based,and inorganic semiconducting materials.Silicon(Si)owing to its mature fabrication process,excellent electrical,optical,thermal properties,and cost efficiency,remains a compelling material choice for flexible electronics.Consequently,the research on ultra-thin Si in the context of flexible electronics is studied rigorously nowadays.The thinning of Si is crucially important for flexible electronics as it reduces its bending stiffness and the resultant bending strain,thereby enhancing flexibility while preserving its exceptional properties.This review provides a comprehensive overview of the recent efforts in the fabrication techniques for forming ultra-thin Si using top-down and bottom-up approaches and explores their utilization in flexible electronics and their applications.

New flexible endoscopic controlled stapler technique for the treatment of Zenker's diverticulum:A case series

AIMTo report about the combination and advantages of a stapler-assisted diverticulotomy performed by flexible endoscopy.METHODSFrom November 2014 till December 2015 17 patients (8 female, 9 male, average age 69.8 years) with a symptomatic Zenker diverticulum (mean size 3.5 cm) were treated by inserting a new 5 mm fully rotatable surgical stapler (MicroCutter30 Xchange, Cardica Inc.) next to an ultrathin flexible endoscope through an overtube. The Patients were under conscious sedation with the head reclined in left position, the stapler placed centrally and pushed forward to the bottom of the diverticulum. The septum was divided by the staple rows under flexible endoscopic control.RESULTSIn eleven patients (64.7%) the stapler successfully divided the septum completely. Mean procedure time was 21 min, medium size of the septum was 2.8 cm (range 1.5 cm to 4 cm). In four patients the septum was shorter than 3 cm, in seven longer than 3 cm. To divide the septum, averagely 1.3 stapler cartridges were used. Two minor bleedings occurred. Major adverse events like perforation or secondary haemorrhage did not occur. After an average time of two days patients were discharged from the hospital. In 6 patients (35.3%) the stapler failed due to a thick septum or insufficient reclination of the head. Follow up endoscopy was performed after an average of two months in 9 patients; 4 patients (44.4%) were free of symptoms, 5 patients (55.6%) stated an improvement. A relapse of symptoms did not occur.CONCLUSIONFlexible endoscopic Zenker diverticulotomy by using a surgical stapler is a new, safe and efficient treatment modality. A simultaneously tissue opening and occlusion prevents major complications.

Adaptable and Dynamic Access Control Decision-Enforcement Approach Based on Multilayer Hybrid Deep Learning Techniques in BYOD Environment

Organizations are adopting the Bring Your Own Device(BYOD)concept to enhance productivity and reduce expenses.However,this trend introduces security challenges,such as unauthorized access.Traditional access control systems,such as Attribute-Based Access Control(ABAC)and Role-Based Access Control(RBAC),are limited in their ability to enforce access decisions due to the variability and dynamism of attributes related to users and resources.This paper proposes a method for enforcing access decisions that is adaptable and dynamic,based on multilayer hybrid deep learning techniques,particularly the Tabular Deep Neural Network Tabular DNN method.This technique transforms all input attributes in an access request into a binary classification(allow or deny)using multiple layers,ensuring accurate and efficient access decision-making.The proposed solution was evaluated using the Kaggle Amazon access control policy dataset and demonstrated its effectiveness by achieving a 94%accuracy rate.Additionally,the proposed solution enhances the implementation of access decisions based on a variety of resource and user attributes while ensuring privacy through indirect communication with the Policy Administration Point(PAP).This solution significantly improves the flexibility of access control systems,making themmore dynamic and adaptable to the evolving needs ofmodern organizations.Furthermore,it offers a scalable approach to manage the complexities associated with the BYOD environment,providing a robust framework for secure and efficient access management.

Study on Component Synthesis Active Vibration Suppression Method Using Zero-placement Technique

The component synthesis active vibration suppression method （CSVS） can be applied to suppress the vibration of flexible systems. By this method, several same or similar time-varying components are arranged according to certain rules along the time axis. The synthesized command can suppress the arbitrary unwanted vibration harmonic while achieving the desired rigid body motion. The number of the components increases rapidly when the number of harmonic vibration is growing. In this article, the CSVS based on zero-placement technique is used to construct the synthesized command to suppress the multi-harmonics simultaneously in the discrete domain. The nature of zero-placement method is to put enough zeros to cancel system poles at necessary points. The designed synthesized command has equal time intervals between each component and which is much easier to be implemented. Using this method, the number of components increases linearly with the increasing of the number of being suppressed harmonics. For the spacecraft with flexible appendages, CSVS based on zero-placement is used to design the time optimal large angle maneuver control strategy. Simulations have verified the validity and superiority of the proposed approach.

Adaptive Fuzzy Backstepping Tracking Control for Flexible Robotic Manipulator

In this paper,an adaptive fuzzy state feedback control method is proposed for the single-link robotic manipulator system.The considered system contains unknown nonlinearfunction and actuator saturation.Fuzzy logic systems(FLSs)and a smooth function are used to approximate the unknownnonlinearities and the actuator saturation,respectively.By com-bining the command-filter technique with the backsteppingdesign algorithm,a novel adaptive fuuzy tracking backsteppingcontrol method is developed.It is proved that the adaptive fuuzycontrol scheme can guarantee that all the variables in the closed-loop system are bounded,and the system output can track thegiven reference signal as close as possible.Simulation results areprovided to illustrate the effectiveness of the proposed approach.

Morphological Engineering of Sensing Materials for Flexible Pressure Sensors and Artificial Intelligence Applications

As an indispensable branch of wearable electronics,flexible pressure sensors are gaining tremendous attention due to their extensive applications in health monitoring,human-machine interaction,artificial intelligence,the internet of things,and other fields.In recent years,highly flexible and wearable pressure sensors have been developed using various materials/structures and transduction mechanisms.Morphological engineering of sensing materials at the nanometer and micrometer scales is crucial to obtaining superior sensor performance.This review focuses on the rapid development of morphological engineering technologies for flexible pressure sensors.We discuss different architectures and morphological designs of sensing materials to achieve high performance,including high sensitivity,broad working range,stable sensing,low hysteresis,high transparency,and directional or selective sensing.Additionally,the general fabrication techniques are summarized,including self-assembly,patterning,and auxiliary synthesis methods.Furthermore,we present the emerging applications of high-performing microengineered pressure sensors in healthcare,smart homes,digital sports,security monitoring,and machine learning-enabled computational sensing platform.Finally,the potential challenges and prospects for the future developments of pressure sensors are discussed comprehensively.

Demand Flexibility of Residential Buildings:Definitions,Flexible Loads,and Quantification Methods

This paper reviews recent research on the demand flexibility of residential buildings in regard to definitions,flexible loads,and quantification methods.A systematic distinction of the terminology is made,including the demand flexibility,operation flexibility,and energy flexibility of buildings.A comprehensive definition of building demand flexibility is proposed based on an analysis of the existing definitions.Moreover,the flexibility capabilities and operation characteristics of the main residential flexible loads are summarized and compared.Models and evaluation indicators to quantify the flexibility of these flexible loads are reviewed and summarized.Current research gaps and challenges are identified and analyzed as well.The results indicate that previous studies have focused on the flexibility of central air conditioning,electric water heaters,wet appliances,refrigerators,and lighting,where the proportion of studies focusing on each of these subjects is 36.7%,25.7%,14.7%,9.2%,and 8.3%,respectively.These flexible loads are different in running modes,usage frequencies,seasons,and capabilities for shedding,shifting,and modulation,while their response characteristics are not yet clear.Furthermore,recommendations are given for the application of white-,black-,and grey-box models for modeling flexible loads in different situations.Numerous static flexibility evaluation indicators that are based on the aspects of power,temporality,energy,efficiency,economics,and the environment have been proposed in previous publications,but a consensus and standardized evaluation framework is lacking.This review can help readers better understand building demand flexibility and learn about the characteristics of different residential flexible loads,while also providing suggestions for future research on the modeling techniques and evaluation metrics of residential building demand flexibility.

A Neural Fuzzy System for Vibration Control in Flexible Structures

An adaptive neural fuzzy (NF) controller is developed in this paper for active vibration suppression in flexible structures. A recurrent identification network (RIN) is developed to adaptively identify system dynamics of the plant. A novel recurrent training (RT) technique is suggested to train the RIN so as to optimize nonlinear input-output mapping and to enhance convergence. The effectiveness of the developed controller and the related techniques has been verified experimentally corresponding to different control scenarios. Test results show that the proposed RIN can effectively recognize the time-varying dynamics of the plant. The RT-based hybrid training technique can improve the adaptive capability of the control system to accommodate different system conditions and enhance the training convergence. The developed NF controller is a robust and stable vibration suppression system, and it outperforms other related NF controllers.

No Rupture Surface Sliding Geo-Technique in Deep Excavation for Static and Especially for Seismic Thrust

In the recent literature concerning the multi-propped bottom-up technique Shanghai Metro Stations Excavations, there is evidence of the importance of the disturbance in terms of greater wall horizontal deflections and consequently vertical settlements in the neighbouring, caused by the late long time of open -cut excavation without propping. Here is proposed, theoretical and pragmatic at the same time, a new approach to face the problem of the wall deflections and the related vertical settlements behind the wall. The solution proposed is indeed to impede any formation of the incipient sliding in the active wedge soil rupture surface, by oblique piling crossing over the rupture surface through a longer pile penetration length in relation to the active wedge before any excavation process starts. This piled-construction will then cut to shape the excavation profiles recurring to loss of piles material. This solution is particularly fit for high seismicity prone areas, because of the minor relative loss of per unit length of pile, caused by the greater depth of the rupture surfaces to get and cross over.

A contemporary step-by-step guide to performing flexible ureterorenoscopy for renal calculi

With advancements in laser technology and urological techniques, flexible ureterorenoscopy has emerged as a vital surgical approach for managing stone disease. Various techniques can be employed to customize endourological stone treatments. Despite the continuous evolution of equipment, it remains crucial to comprehend the fundamental steps of the procedure. This paper offers a comprehensive step-by-step guide that integrates the latest advancements in both scopes and lasers. Additionally, it outlines potential pitfalls and strategies to circumvent them, aiming to achieve optimal stone clearance and deliver individualized patient care safely and efficiently.

作物茎秆膨胀收缩监测柔性可穿戴传感器研制与试验

作物茎秆膨胀和收缩变化与其水分状态密切相关,实时监测茎秆的膨胀和收缩变化能够及时掌握作物水分状态,对指导灌溉、提高农业水资源利用率具有重要意义。目前,对于作物茎秆膨胀和收缩变化的监测主要采用基于线性微位移测量原理的传感器,通过测量茎秆的膨胀和收缩引起的位移变化来反映水分状态,存在体积大、价格高、安装不便等问题。为此,该研究提出了一种基于压阻效应的柔性可穿戴传感器,采用柔性压力电极作为传感元件,贴附在作物茎秆表面,通过监测茎秆膨胀和收缩引起的压力变化来反映作物的水分状态,压力检测电路和数据采集电路将作物茎秆的压力信号转换成电信号进行输出和存储。首先在实验室环境下对传感器性能进行测试和标定,然后在温室环境下将传感器安装在番茄茎秆上观测番茄茎秆的压力变化,并与线性微位移传感器观测结果进行比较,最后在充分灌溉和水分亏缺2种条件下观测番茄茎秆的膨胀和收缩变化。结果表明,柔性压力传感器稳定性测试的平均相对变化率为0.109%;弯折前后引起的输出变化非常小,可以忽略不计;标定结果的决定系数大于0.99,最合适的工作压力范围为2~100 kPa;实验室环境下,柔性压力传感器与线性微位移传感器输出值之间的决定系数为0.9551;温室环境下,充分灌溉组中柔性压力传感器与线性微位移传感器输出值变化趋势一致,两者之间的决定系数为0.7672,亏缺灌溉组中两类传感器输出值均因水分亏缺而呈现下降趋势,输出值之间的决定系数为0.8519。本文所设计的柔性可穿戴压力传感器不仅能够实时监测番茄茎秆的膨胀和收缩变化,还可以对番茄亏水胁迫进行诊断,为实现高效节水灌溉提供重要的技术支撑。

多周期常减压蒸馏装置换热网络用能变化与柔性优化

常减压蒸馏装置能耗在整个炼油厂中最高,优化其换热网络是节能的有效手段。考虑到所加工油品会发生变化,以往针对特定原油设计的换热网络在处理其他原油时表现不再最优。提出一种多周期柔性优化方法:首先对不同原油周期进行流程模拟,随后模拟现行换热网络,辨识夹点位置偏移,发现不合理用能发生位置,通过改变管路结构并调节换热匹配,提高换热网络柔性,消除部分共有的跨夹点传热。在某炼油厂的应用结果表明,多周期柔性设计可在周期1、周期2、周期3、周期4分别节约1421,880,3842,3421 kW的加热炉热负荷和等量的冷却负荷。对多周期换热网络用能变化规律的深入研究和柔性设计,可为炼油厂节能降耗做出更大贡献。

Demonstration of radar-aided flexible communication in a photonics-based W-band distributed integrated sensing and communication system for 6G

This paper experimentally demonstrates a distributed photonics-based W-band integrated sensing and communication(ISAC) system, in which radar sensing can aid the communication links in alignment and data rate estimation. As a proof-of-concept, the ISAC system locates the users, guides the alignment, and sets a communication link with the estimated highest data rate. A peak net data rate of 68.6 Gbit/s and a target sensing with a less-than-1-cm error and a sub-2-cm resolution have been tested over a 10-km fiber and a 1.15-m free space transmission in the photonics-based W-band ISAC system. The achievable net data rates of the users at different locations estimated by sensing are experimentally verified.

小型化全光纤激光器壳体结构设计与分析

为了进一步优化小型化激光器的性能,在一般性原则的基础上设计了一款输出功率大于10 W、1030 nm高稳定性的小型化全光纤激光器壳体结构。壳体体积为220 mm×270 mm×75 mm,质量小于7 kg;壳体结构采用柔性支撑的减振设计,并可使激光器在温度-55℃~45℃的小型化平台下保持正常运行。利用有限元分析软件对激光器壳体进行了热分析与随机振动分析,按照设计图纸对小型化全光纤激光器样机进行了加工,并进行了实验验证。结果表明,激光器壳体在45℃下,激光器最热面温度为49.5℃,温升约为4.5℃,散热性能良好;在随机振动功率谱密度总均方根10.77 g的实验条件下,激光器最大3σ应力为171 MPa,随机振动响应均方根值仅为24.5 g,壳体结构力学性能良好;激光器壳体结构的散热性能以及力学性能完全满足设计要求,实验结果与仿真结果吻合度较高。该研究为小型化光纤激光器项目的具体实施提供了一定参考。

用于常见环境污染物检测的柔性荧光传感器

随着工业化进程的不断推进,环境污染问题日益突出,研发针对不同种类污染物检测的传感器及其阵列对治理环境污染、保障人们健康生活意义重大。具有检测灵敏度高、响应速度快等特征的荧光分子探针逐渐成为污染物检测的重要工具,将其通过物理或化学方法固定于柔性基质表面制备的荧光传感薄膜是一种发展潜力巨大的微痕量物质检测装置,具有操作简单、便于携带、尺寸可调和不污染待测体系等优势,尤其是对当前引起广泛关注的智能可穿戴材料的研究具有极大的促进作用。该文综述了近几年基于荧光探针技术的柔性传感薄膜与器件对常见气相、液相环境污染物进行检测的研究现状,并总结了该领域目前存在的一些问题和挑战,展望了该技术在传感单元和基底多元拓展和优化、复合型柔性传感器阵列、环境友好型薄膜再生技术等方面的未来发展方向。

基于分布式监测的历史建筑结构整体变形计算方法研究

随着监测技术的发展,传统二维图表已难以满足日益增长的结构安全监测需求。互联网与计算机三维可视化技术,使监测数据呈现出以多维度、更加真实与实时的形式进行展现的发展趋势。在此过程中,利用分布式监测进行结构整体变形计算,成为监测数据多维展示的关键。在结构力学柔度矩阵的基础上,提出广义柔度矩阵,建立了基于广义柔度矩阵的结构整体变形计算方法,并在上海音乐厅观众厅穹顶木屋架监测中进行了应用。该方法可为后续结构安全监测数据的三维可视化提供技术支撑。

软瓷柔性面砖材料在某建筑外墙施工中的应用研究

软瓷柔性面砖是一种新型墙面装饰材料,施工操作便捷,克服了传统外墙饰面质量重、柔韧性差,避免像瓷砖等刚性材料因湿贴热胀冷缩空鼓而产生的脱落等问题,实际应用效果较好。研究以新建某干部学院二期工程中的会议中心、学员公寓为例,对软瓷柔性面砖施工设计及施工工艺进行重点介绍,以期提升施工质量,并保证了工程的安全性及美观性。

安全稳定控制系统在渝鄂直流背靠背联网工程的应用

渝鄂直流背靠背联网工程是目前世界上电压等级高、输送容量大、功能最全的柔性直流工程。渝鄂联网安全稳定控制系统由渝鄂直流背靠背联网工程南通道安全稳定控制系统(施州换流站)和渝鄂直流背靠背联网工程北通道安全稳定控制系统(宜昌换流站)两部分组成,覆盖西南和华中地区。该系统主要解决施州/宜昌换流站直流双极闭锁引起的频率问题和长南线静稳破坏问题以及西南和华中主网异步运行后的系统低频越限问题,采取切机或调制相关直流功率的控制措施。文章介绍了渝鄂直流背靠背联网工程安全稳定控制系统的架构设计、配置、控制策略以及新技术。该系统自投运后,已正确动作多次,保证了西南和华中电网的安全稳定运行。

白沙洲长江大桥桥塔墩防撞关键技术

白沙洲长江大桥主桥为双塔双索面斜拉桥,桥塔均采用顺桥向单柱式、横桥向钻石形结构,基础为40根?1.55 m钻孔灌注桩,承台尺寸为32.4 m(横桥向)×20.4 m(顺桥向)×5 m(高),美国AASHTO规范模型计算显示桥塔墩年撞损频率较高,且原设计船舶撞击标准已无法满足当前通航标准及长江航运发展需求。为提升该桥桥塔墩的防撞能力,设计了组合型浮动式钢+复合材料防撞设施。该设施采用多级耗能体系及柔性防船撞结构,增强了大桥桥塔墩的防撞性能,并通过下塔柱增大截面补强使防撞设施在下塔柱范围内可随着水位自由升降,进一步增强了桥塔墩自身的防撞性能。下塔柱增大截面补强采用开口式单双壁组合型围堰,实现了补强的无水施工;组合型浮动式钢+复合材料防撞设施在工厂内分节段制造,并采用长效防腐技术延长了使用寿命。实施该防撞方案后,该桥桥塔墩能抵御3 000吨级满载船舶的水平撞击力,所受船舶撞击力明显低于桥塔墩自身的允许抗撞力,满足设防要求。

论烟叶烘烤工艺的灵活应用

针对生产上烟叶烘烤工艺应用不当而造成的损失,提出应根据烟叶素质、干湿球温度计挂放位置、烤房的结构和性能等条件灵活应用烘烤工艺,才能确保烟叶烘烤质量,提高烟叶的可用性。