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基于异构图神经网络的D2D联合功率分配
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作者 陈发堂 徐霄鹏 +1 位作者 王文浩 刘泽 《电讯技术》 北大核心 2025年第5期693-699,共7页
传统的功率分配算法由于复杂的矩阵运算与迭代所造成的高时延,在实际通信中实时获取信道信息十分困难,当前重要的研究方向是在系统性能和计算复杂度之间找到有效平衡。针对终端直通(Device-to-Device,D2D)用户与蜂窝用户的联合功率分配... 传统的功率分配算法由于复杂的矩阵运算与迭代所造成的高时延,在实际通信中实时获取信道信息十分困难,当前重要的研究方向是在系统性能和计算复杂度之间找到有效平衡。针对终端直通(Device-to-Device,D2D)用户与蜂窝用户的联合功率分配问题,提出一种异构功率控制图神经网络(Heterogeneous Power Control Graph Neural Network,HPCGNN)算法,旨在最大化所有用户的加权和速率。首先通过构建干扰的异构图,将信道和噪声等信息嵌入到图的节点和边;再由HPCGNN完成消息传递和更新,采用无监督学习方式优化深度神经网络(Deep Neural Network,DNN)参数,最终得到最佳的功率分配。仿真结果表明,相较于其他深度学习算法,所提算法能够有效提高系统性能,且在损失5%性能下相较分式规划(Fractional Programming,FP)能降低82%~98%的时间复杂度。 展开更多
关键词 d2d 功率分配 异构图神经网络
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Energy-Efficient Architecture and Technologies for Device to Device(D2D)Based Proximity Service 被引量:6
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作者 ZHANG Bo WANG Yufeng +1 位作者 JIN Qun MA Jianhua 《China Communications》 SCIE CSCD 2015年第12期32-42,共11页
Considering that modern mobile terminals possess the capability to detect users'proximity,and offer means to directly communicate and share content with the people in close area,Device-to-Device(D2D)based Proximit... Considering that modern mobile terminals possess the capability to detect users'proximity,and offer means to directly communicate and share content with the people in close area,Device-to-Device(D2D)based Proximity Services(ProSe)have recently witnessed great development,which enable users to seek for and utilize relevant value in their physical proximity,and are capable to create numerous new mobile service opportunities.However,without a breakthrough in battery technology,the energy will be the biggest limitation for ProSe.Through incorporating the features of ProSe(D2D communication technologies,abundant built-in sensors,localization-dependent,and context-aware,etc.),this paper thoroughly investigates the energy-efficient architecture and technologies for ProSe from the following four aspects:underlying networking technology,localization,application and architecture features,context-aware and user interactions.Besides exploring specific energy-efficient schemes pertaining to each aspect,this paper offers a perspective for research and applications.In brief,through classifying,summarizing and optimizing the multiple efforts on studying,modeling and reducing energy consumption for ProSe on mobile devices,the paper would provide guide for developers to build energy-efficient ProSe. 展开更多
关键词 Proximity Service(ProSe) Energy-eficient device to device(d2d)
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D2D辅助移动边缘计算下的任务卸载和资源分配研究 被引量:1
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作者 占慧芳 李正权 +1 位作者 武贵路 聂高峰 《电子测量与仪器学报》 北大核心 2025年第1期90-100,共11页
针对移动边缘计算(MEC)环境下终端设备任务卸载时资源分配效率低的问题,提出一种基于终端直传通信(D2D)技术辅助MEC系统的多任务部分卸载方案。该方案基于块坐标下降法(BCD)实现任务卸载和资源分配策略的联合优化,借助动态定价策略激励... 针对移动边缘计算(MEC)环境下终端设备任务卸载时资源分配效率低的问题,提出一种基于终端直传通信(D2D)技术辅助MEC系统的多任务部分卸载方案。该方案基于块坐标下降法(BCD)实现任务卸载和资源分配策略的联合优化,借助动态定价策略激励服务型设备(SSDs)共享剩余可用计算资源,以最小化系统执行成本。首先利用重构-线性化技术(RLT)和凸优化理论优化计算资源分配和卸载比例划分,决定任务分配至本地计算、D2D卸载和边缘卸载时数据量;其次根据优化后卸载策略选择最优SSDs执行D2D卸载任务。仿真结果表明,与传统部分卸载方案、中继辅助卸载方案和协同计算卸载方案相比,所提卸载方案在不同设备数目下系统执行总成本分别减少27.62%、25.58%和19.98%,在不同最大容忍时延条件下系统执行总成本分别平均下降约43.35%、38.19%和36.79%及在不同任务数据大小下系统执行总成本分别平均下降约36.47%、30.60%和29.15%。进一步实验表明,与贪婪卸载方案相比,所提卸载方案在不同设备数目、最大容忍时延和任务数据量下分别平均优化7.59%、0.39%和3.10%系统执行成本,有效提高系统资源利用率并降低执行成本。 展开更多
关键词 移动边缘计算 任务卸载 d2d通信 资源分配 块坐标下降法
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5G-D2D增强的无人机集群相对导航方法 被引量:1
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作者 熊骏 解相朋 周峰 《航空科学技术》 2025年第3期48-53,共6页
精确的相对导航状态估计是无人机集群飞行的关键环节。针对传统无人机集群中的相对导航系统在卫星导航可用性较差时性能下降的问题,本文提出了一种基于5G-D2D增强的无人机相对导航状态估计方案。该方案基于伪距双差量测、5G-D2D量测特... 精确的相对导航状态估计是无人机集群飞行的关键环节。针对传统无人机集群中的相对导航系统在卫星导航可用性较差时性能下降的问题,本文提出了一种基于5G-D2D增强的无人机相对导航状态估计方案。该方案基于伪距双差量测、5G-D2D量测特性设计了相对状态滤波器的量测模型,并基于航姿系统的输出特性设计了无人机之间的相对运动模型,进而采用扩展卡尔曼滤波(EKF)作为估计框架融合所有导航传感信息。仿真结果表明,5G-D2D量测能够有效提升仅依赖卫星的相对导航系统性能,且在可用卫星数目较少时提升效果更为明显。本文研究能够有效降低无人机相对导航系统对于卫星导航的依赖,并提升相对导航状态估计精度。 展开更多
关键词 无人机 相对导航 5G-d2d 伪距 航姿系统
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基于IRS的D2D隐蔽通信
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作者 顾蔡晨 王斌 +1 位作者 黄纯华 王文鼐 《南京邮电大学学报(自然科学版)》 北大核心 2025年第2期47-55,共9页
对D2D(Device to Device)通信系统的隐蔽通信问题进行研究,提出了一种基于智能反射面(Intelligent Reflecting Surfaces,IRS)的D2D通信系统,该系统采用双IRS模式。首先分析了各信号的信干噪比(SINR)和各自的期望值,并据此推导出系统遍... 对D2D(Device to Device)通信系统的隐蔽通信问题进行研究,提出了一种基于智能反射面(Intelligent Reflecting Surfaces,IRS)的D2D通信系统,该系统采用双IRS模式。首先分析了各信号的信干噪比(SINR)和各自的期望值,并据此推导出系统遍历总容量的解形式,接着针对隐蔽通信建立了二元假设问题,推导出误检测率的解形式,并据此计算出平均最小误检测率。除此之外,还分析了无IRS系统的遍历总容量和平均最小误检测率,与双IRS系统进行对比。仿真结果表明,双IRS系统的遍历总容量和平均最小误检测率优于无IRS系统,双IRS系统能够比传统的无IRS系统获得更高的容量和更低的误检测率。 展开更多
关键词 d2d 智能反射面 隐蔽通信 遍历总容量
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智能超表面赋能的D2D隐蔽通信策略研究
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作者 吕璐 郑彭玮 +1 位作者 杨龙 陈健 《电子与信息学报》 北大核心 2025年第7期2023-2035,共13页
为了应对目前设备到设备(D2D)隐蔽通信研究中引入额外不确定性源而带来高成本、高功耗的问题,该文提出一种智能超表面(RIS)赋能的D2D隐蔽传输方法。该方法借助RIS为合法用户创造更好的无线传播条件的同时,利用RIS的相移不确定性来混淆... 为了应对目前设备到设备(D2D)隐蔽通信研究中引入额外不确定性源而带来高成本、高功耗的问题,该文提出一种智能超表面(RIS)赋能的D2D隐蔽传输方法。该方法借助RIS为合法用户创造更好的无线传播条件的同时,利用RIS的相移不确定性来混淆监听者的检测。为探究所提方法的隐蔽性能增益,在保证监听者低检测概率以及满足蜂窝用户服务质量的条件下,构建通过联合优化蜂窝用户、D2D发射机的发射功率以及RIS相移来最大化D2D用户的隐蔽速率的优化问题。为解决上述变量和约束高度耦合的非凸优化问题,提出一种高效的基于高斯随机化的交替优化算法,求解出最优的蜂窝用户和D2D发射机的发射功率以及RIS相移。仿真结果表明,RIS的辅助给D2D隐蔽传输系统带来了显著的性能提升,通过增加RIS反射元件数量,或提升蜂窝用户发射功率为D2D隐蔽传输提供更好的掩体,都可以进一步提升隐蔽通信性能。 展开更多
关键词 智能超表面 d2d网络 隐蔽通信
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Device Discovery in D2D Communication: Scenarios and Challenges
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作者 Adeel Iqbal Ali Nauman +4 位作者 Riaz Hussain Irfan Latif Khan Ali Khaqan Sana Shuja Sung Won Kim 《Computers, Materials & Continua》 SCIE EI 2023年第4期1735-1750,共16页
Device to Device (D2D) communication is expected to be anessential part of 5G cellular networks. D2D communication enables closeproximitydevices to establish a direct communication session. D2D communicationoffers man... Device to Device (D2D) communication is expected to be anessential part of 5G cellular networks. D2D communication enables closeproximitydevices to establish a direct communication session. D2D communicationoffers many advantages, such as reduced latency, high data rates,range extension, and cellular offloading. The first step to establishing a D2Dsession is device discovery;an efficient device discovery will lead to efficientD2D communication. D2D device further needs to manage its mode of communication,perform resource allocation, manage its interference and mostimportantly control its power to improve the battery life of the device. Thiswork has developed six distinct scenarios in which D2D communication canbe initiated, considering their merits, demerits, limitations, and optimizationparameters. D2D communication procedures for the considered scenarioshave been formulated, based upon the signal flow, containing device discovery,resource allocation, and session teardown. Finally, latency for each scenariohas been evaluated, based on propagation and processing delays. 展开更多
关键词 d2dcommunication device discovery LATENCY resource allocation
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IRS-D2D混合通信车联网场景下的资源优化策略 被引量:1
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作者 吴微 徐涴砯 《计算机应用研究》 北大核心 2025年第2期560-565,共6页
针对城市道路车联网存在视距链路阻塞和资源有限等问题,提出一种基于混合通信车联网场景下的智能反射面(IRS)辅助的资源优化策略。该方案构建了IRS辅助的车联网系统,并在该系统中使用D2D技术增加距离基站较远车辆的数据传输能力。为了... 针对城市道路车联网存在视距链路阻塞和资源有限等问题,提出一种基于混合通信车联网场景下的智能反射面(IRS)辅助的资源优化策略。该方案构建了IRS辅助的车联网系统,并在该系统中使用D2D技术增加距离基站较远车辆的数据传输能力。为了提升系统的频谱效率,在该系统中引入认知无线电技术(CR),将D2D用户下垫式地接入基站用户信道,在不超过基站用户预设干扰门限的情况下传输数据。针对所构建的IRS-D2D混合通信车联网系统模型,提出基于系统和速率最大化的有限资源优化分配问题。在满足用户通信服务质量的条件下,通过联合优化功率分配、IRS相移和频谱资源分配的方法,实现系统和速率的最大化。由于提出的优化问题是一个多变量的混合整数非凸问题,难以在多项式时间内求得最优值,故采用两阶段联合分配方案。具体地,在第一阶段,联合优化功率分配和IRS相移,通过松弛变量法得到局部最优解。在第二阶段,使用交替优化算法进行频谱资源分配。仿真结果表明,IRS辅助车联网的资源优化策略提升了系统的和速率和频谱效率,所提资源分配方案优于现有方案。由此IRS-D2D的通信技术可以应用在车联网中。 展开更多
关键词 智能反射面 车联网 d2d 认知无线电 资源分配
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基于多智能体强化学习的D2D通信资源分配算法研究
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作者 李陶深 漆治军 杜利俊 《燕山大学学报》 北大核心 2025年第5期461-470,共10页
为了解决蜂窝网络中端到端(Device-to-Device,D2D)通信的同频干扰问题,考虑到小区内蜂窝用户的移动性,通过引入无线携能通信技术,提出一种基于双深度Q-网络的分布式资源分配算法。该算法在满足设备最低服务质量要求和不完全信道状态信... 为了解决蜂窝网络中端到端(Device-to-Device,D2D)通信的同频干扰问题,考虑到小区内蜂窝用户的移动性,通过引入无线携能通信技术,提出一种基于双深度Q-网络的分布式资源分配算法。该算法在满足设备最低服务质量要求和不完全信道状态信息等约束条件下,帮助D2D链路学习最优策略,以此缓解系统中存在的干扰,实现分布式资源分配和D2D链路的能量效率最大化。首先,将D2D通信的资源分配问题表述为马尔可夫决策过程;然后,将分配问题分解为功率控制和信道分配两个子问题,并根据强化学习技术对问题进行转化,建模为具有多个智能体的资源分配问题,设计训练算法。仿真实验结果表明,所提出的分配算法能有效收敛,明显提升了D2D链路层的能量效率和D2D链路的吞吐量,具有一定的可行性、有效性和先进性。 展开更多
关键词 d2d通信 无线携能通信 功率控制 资源分配 多智能体强化学习
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Physics of 2D Materials for Developing Smart Devices 被引量:1
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作者 Neeraj Goel Rahul Kumar 《Nano-Micro Letters》 2025年第8期449-490,共42页
Rapid industrialization advancements have grabbed worldwide attention to integrate a very large number of electronic components into a smaller space for performing multifunctional operations.To fulfill the growing com... Rapid industrialization advancements have grabbed worldwide attention to integrate a very large number of electronic components into a smaller space for performing multifunctional operations.To fulfill the growing computing demand state-of-the-art materials are required for substituting traditional silicon and metal oxide semiconductors frameworks.Two-dimensional(2D)materials have shown their tremendous potential surpassing the limitations of conventional materials for developing smart devices.Despite their ground-breaking progress over the last two decades,systematic studies providing in-depth insights into the exciting physics of 2D materials are still lacking.Therefore,in this review,we discuss the importance of 2D materials in bridging the gap between conventional and advanced technologies due to their distinct statistical and quantum physics.Moreover,the inherent properties of these materials could easily be tailored to meet the specific requirements of smart devices.Hence,we discuss the physics of various 2D materials enabling them to fabricate smart devices.We also shed light on promising opportunities in developing smart devices and identified the formidable challenges that need to be addressed. 展开更多
关键词 2D materials HETEROSTRUCTURES Smart devices Van der Waals Flexible electronics
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基于CNN的D2D通信信道分配和功率控制联合优化
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作者 褚盛雄 陈晓梅 《通信技术》 2025年第10期1092-1099,共8页
针对高复杂度的动态无线环境下资源分配和实时性不足的问题提出了一种基于卷积神经网络(CNN)的设备到设备(D2D)通信信道分配与功率控制联合优化方法。首先,对蜂窝用户和D2D用户并存的复杂无线通信场景进行了系统建模,包括信道与干扰模... 针对高复杂度的动态无线环境下资源分配和实时性不足的问题提出了一种基于卷积神经网络(CNN)的设备到设备(D2D)通信信道分配与功率控制联合优化方法。首先,对蜂窝用户和D2D用户并存的复杂无线通信场景进行了系统建模,包括信道与干扰模型。其次,分析确定了联合优化目标及约束条件,在此基础上,计算得到用户位置矩阵和信道增益矩阵,并将其作为CNN模型的输入,通过不断学习迭代,输出最优的信道分配概率和功率控制值,并由此计算系统吞吐量。最后,对所提方法进行了仿真验证,结果表明,所提方法相较于传统匈牙利算法和粒子群优化(PSO)算法,系统中D2D用户的最大吞吐量有较显著的提升。 展开更多
关键词 d2d CNN 资源分配 功率控制
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面向依赖任务的D2D辅助边缘计算卸载与资源分配优化
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作者 朱睿 蒋雪阳 孙彦赞 《计量与测试技术》 2025年第12期6-9,15,共5页
随着5G技术的快速发展,面向视频流传输、自动驾驶的计算卸载与资源分配问题在边缘计算环境中日益重要。由于实际场景中传统边缘计算架构面临用户计算与通信资源竞争加剧、网络负载较大等问题。因此,本文提出一种面向依赖任务的D2D辅助... 随着5G技术的快速发展,面向视频流传输、自动驾驶的计算卸载与资源分配问题在边缘计算环境中日益重要。由于实际场景中传统边缘计算架构面临用户计算与通信资源竞争加剧、网络负载较大等问题。因此,本文提出一种面向依赖任务的D2D辅助边缘计算卸载与资源分配优化系统,通过引入PPO算法,结合优化卸载决策及子信道、发射功率和终端计算资源的分配,最小化用户的平均时延和能耗成本。结果表明,该系统在不同场景下均优于基线算法。 展开更多
关键词 依赖任务 d2d 计算卸载 资源分配 PPO
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能量有效的RIS辅助D2D通信干扰对齐算法
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作者 马蓓 《武汉大学学报(工学版)》 北大核心 2025年第9期1510-1516,共7页
针对可重构智能超表面(reconfigurable intelligent surface,RIS)辅助的端到端(device-to-device,D2D)多用户通信系统,提出一种能量有效的D2D发送功率分配与RIS相移矩阵设计方法。该方法考虑D2D用户的最小速率约束、最大发送功率约束以... 针对可重构智能超表面(reconfigurable intelligent surface,RIS)辅助的端到端(device-to-device,D2D)多用户通信系统,提出一种能量有效的D2D发送功率分配与RIS相移矩阵设计方法。该方法考虑D2D用户的最小速率约束、最大发送功率约束以及干扰对齐约束,基于Nakagami-m衰落信道模型,建立了一个关于发送功率与RIS相移矩阵联合优化的能效最大化问题。通过交替迭代方法对这一非凸问题进行联合优化,利用干扰对齐算法求解RIS相移矩阵,利用分式规划求解最优发送功率分配解。仿真结果表明,与现有算法相比,所提算法能够显著提升系统的能效与谱效性能。 展开更多
关键词 可重构智能超表面 d2d通信 相移矩阵 能效
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非完美SIC D2D-NOMA系统吞吐量最大化功率分配
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作者 张东方 叶成荫 《电子测量技术》 北大核心 2025年第8期80-87,共8页
针对D2D-NOMA系统在非完美串行干扰消除条件下的吞吐量最大化问题,提出了一种基于非完美SIC的D2D-NOMA系统吞吐量最大化算法。首先在蜂窝用户和D2D用户的服务质量、最大发射功率下,考虑非完美SIC条件,建立一个以D2D-NOMA系统的吞吐量最... 针对D2D-NOMA系统在非完美串行干扰消除条件下的吞吐量最大化问题,提出了一种基于非完美SIC的D2D-NOMA系统吞吐量最大化算法。首先在蜂窝用户和D2D用户的服务质量、最大发射功率下,考虑非完美SIC条件,建立一个以D2D-NOMA系统的吞吐量最大化为目标的优化模型。然后将模型转换为以吞吐量为奖励的马尔可夫决策过程。利用TD3算法设计了一个功率分配算法,实现了系统吞吐量最大化。经仿真验证,所提出的算法与DDPG算法、遗传算法和随机功率分配算法相比,非完美SIC下D2D-NOMA系统的吞吐量分别提高了约14%、25%和40%,也展现出更优的收敛性和公平性。 展开更多
关键词 非完美SIC d2d-NOMA系统 吞吐量最大化 TD3算法
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Solution-based manufacturing of 2D materials for memristive device applications
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作者 Kijeong Nam Gwang Ya Kim +3 位作者 Dongjoon Rhee Hyesung Park Deep Jariwala Joohoon Kang 《International Journal of Extreme Manufacturing》 2025年第5期1-50,共50页
Two-dimensional (2D) materials have attracted significant attention as resistive switching materials for two-terminal non-volatile memory devices, often referred to as memristors, due to their potential for achieving ... Two-dimensional (2D) materials have attracted significant attention as resistive switching materials for two-terminal non-volatile memory devices, often referred to as memristors, due to their potential for achieving fast switching speeds and low power consumption. Their excellent gate tunability in electronic properties also enables hybrid devices combining the functionality of memory devices and transistors, with the possibility of realizing large-scale memristive crossbar arrays with high integration density. To facilitate the use of 2D materials in practical memristor applications, scalable synthesis of 2D materials with high electronic quality is critical. In addition, low-temperature integration for complementary metal oxide semiconductor (CMOS) back-end-of-line (BEOL) integration is important for embedded memory applications. Solution-based exfoliation has been actively explored as a facile, cost-effective method for the mass production and low-temperature integration of 2D materials. However, the films produced from the resulting 2D nanosheet dispersions exhibited poor electrical properties in the early stages of research, thereby hindering their use in electronic devices. Recent progress in the exfoliation process and post-processing has led to significant improvements in the electronic performance of solution-processed 2D materials, driving increased adoption of these materials in memristor research. In this review article, we provide a thorough overview of the progress and current status of memristive devices utilizing solution-processed 2D resistive switching layers. We begin by introducing the electrical characteristics and resistive switching mechanisms of memristors fabricated with conventional materials to lay the groundwork for understanding memristive behavior in 2D materials. Representative solution-based exfoliation and film formation techniques are also introduced, emphasizing the benefits of these approaches for obtaining scalable 2D material films compared to conventional methods such as mechanical exfoliation and chemical vapor deposition. Finally, we explore the electrical characteristics, resistive switching mechanisms, and applications of solution-processed 2D memristive devices, discussing their advantages and remaining challenges. 展开更多
关键词 memristor neuromorphic device 2D materials solution-based manufacturing
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Changshu Textile Machinery:Focusing on the shedding devices R&D for more than 60 years
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《China Textile》 2025年第5期47-47,共1页
Changshu Textile Machinery Works Co.,Ltd.was founded in 1958 and is a professional R&D and manufacturing enterprise of looms shedding device in China.The company's products cover three series of shedding devic... Changshu Textile Machinery Works Co.,Ltd.was founded in 1958 and is a professional R&D and manufacturing enterprise of looms shedding device in China.The company's products cover three series of shedding devices for looms(Dobby,Jacquard,Cam Motion),forming a series of products with electronic shedding devices as the main products,and mechanical shedding devices as the auxiliary products.D2876pro electronic dobby The D2876pro electronic dobby is a high-performance equipment designed for a maximum operating speed of 800rpm.It has 16 cams,and 12mm of pitch,with a high installation type.The shedding type is double lift and full clear open.Its maximum wefts is 12,800 and 100,000.It has a two-stage filtration lubrication with a gerotor pump oil recycle system,and it is suitable for water-jet looms. 展开更多
关键词 dobby loom d pro electronic dobby high performance equipment electronic shedding devices shedding device electronic dobby shedding devices
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Joint Robust Beamforming Design for WPT-Assisted D2D Communications in MISO-NOMA:Fractional Programming and Deep Reinforcement Learning
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作者 Jiao Shiyu Fang Fang Ding Zhiguo 《China Communications》 2025年第12期307-325,共19页
This paper introduces a framework aimed at aiding the development of sixth-generation(6G)ultra-massive machine type communications(um-MTC).Precisely,the deployment of wireless power transfer(WPT)supported device-to-de... This paper introduces a framework aimed at aiding the development of sixth-generation(6G)ultra-massive machine type communications(um-MTC).Precisely,the deployment of wireless power transfer(WPT)supported device-to-device(D2D)communication occurs within multiple-input singleoutput non-orthogonal multiple access(MISONOMA)downlink networks to facilitate spectrum and energy collaboration.A pure fractional programming(PFP)algorithm is proposed to maximize the WPT-assisted device’s energy efficiency.An optimal closed-form solution for determining the time-switching coefficient of the WPT device is provided.For the robust beamforming design,the complex multi-dimension quadratic transform is applied.Moreover,the paper applies the deep deterministic policy gradient(DDPG)-based approach to directly address the problem and compares it with the proposed algorithm.Simulation outcomes highlight two key insights:1)The PFP algorithm surpasses the performance of the DRL-based algorithm when the acquired channel state information(CSI)is accurate or contains negligible errors,while the opposite is true for imperfect CSI 2)The higher energy efficiency gains can be achieved in NOMA scheme than that in Orthogonal Multiple Access(OMA)scheme. 展开更多
关键词 DRL d2d fractional-programming NOMA WPT
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一种基于分级控制的D2D资源分配方法分析
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作者 肖清华 《邮电设计技术》 2025年第1期39-42,共4页
动态分析待接入D2D用户对的业务需求,结合蜂窝用户的资源占用情况,对系统可利用资源进行统一评估。计算出待接入D2D用户对的分级评估值,结合阈值参数,差异化区分出3种分级控制场景。最后,采用Matlab工具对本算法和之前的模糊聚类算法(... 动态分析待接入D2D用户对的业务需求,结合蜂窝用户的资源占用情况,对系统可利用资源进行统一评估。计算出待接入D2D用户对的分级评估值,结合阈值参数,差异化区分出3种分级控制场景。最后,采用Matlab工具对本算法和之前的模糊聚类算法(包括功控及无功控)进行了仿真对比验证。结果表明,本算法在接入次数累计分布及系统容量等方面有着更均衡的性能提升。 展开更多
关键词 5G d2d 分级控制 模糊聚类 资源分配
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3D Printed PEDOT:PSS Flexible Electrochromic Devices for Patterned Displays
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作者 Manting Song Changchen Gong Ximei Liu 《Journal of Polymer Materials》 2025年第1期111-123,共13页
Flexible electrochromic devices(FECDs)demonstrate significant potential for applications in wearable elec-tronics,military camouflage,and flexible smart displays.As a crucial electrochromic material,poly(3,4-ethylened... Flexible electrochromic devices(FECDs)demonstrate significant potential for applications in wearable elec-tronics,military camouflage,and flexible smart displays.As a crucial electrochromic material,poly(3,4-ethylenedioxythiophene):polystyrene sulfonate(PEDOT:PSS)is widely used in FECDs due to its excellent mechanical flexibility,tunable conductivity,and non-toxicity.However,the manufacturing process for patterned PEDOT:PSS electrochromic devices remains intricate,costly,and challenging to personalize.To address this challenge,we have developed a 3D-printable ink with controllable rheological properties through a concentration-tuning strategy,enabling programmable,patterned printing of PEDOT-based conductive polymer electrochromic layers.The 3D-printed FECDs exhibit outstanding electrochromic performance,including a high optical contrast(up to 47.9%at 635 nm),fast response times(t_(c)=1.6 s;t_(b)=0.6 s),high coloration efficiency(352 cm^(2) C^(-1)),and good cycling stability(with only a 9.3%decrease in optical contrast after 100 electrochemical cycles).Finally,we utilize 3D printing technology to construct flexible,patterned PEDOT:PSS electrochromic devices with bespoke butterfly designs.This work establishes the theoretical foundation for the application of 3D printing technology in PEDOT:PSS flexible electrochromic devices. 展开更多
关键词 3D printing PEDOT:PSS flexible electrochromic device patterned displays
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Unveiling transition metal dinitrides for high-efficiency information devices through systematic first-principles calculations
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作者 Jun-Fei Ding Qiu-Shi Yao +4 位作者 Yun-Peng Qu Farid Man-shaii Shao-Lei Wang Xiao-Si Qi Yao Liu 《Rare Metals》 2025年第7期4789-4800,共12页
Currently,the development of high-efficiency two-dimensional(2D)transistors is still hindered by the limited availability of suitable semiconductors and the contact resistance between the metal contact and the 2D semi... Currently,the development of high-efficiency two-dimensional(2D)transistors is still hindered by the limited availability of suitable semiconductors and the contact resistance between the metal contact and the 2D semiconductors.Endeavors to address these challenges are highly desired.In this study,we conducted a comprehensive exploration of the potential 2D transition metal dinitrides(TMN_(2)s,TM=all the 3d,4d and 5d transition metals)with hexagonal(h-)and trigonal(t-)phases through systematic first-principles calculations.Among all h-TMN_(2)s and t-TMN_(2)s structures,we identified 8 TMN_(2)s that exhibit dynamical and thermal stability at room temperature.Of these,the h-TiN_(2),h-ZrN_(2)and h-HfN_(2)arefound to be semiconductors,and their direct bang gap,calculated at the HSE06 level,are 1.48,1.96 and 2.64 eV,respectively.The electron and hole mobility(μ_(e)andμ_(h))of these three structures exceed 1×10^(4)and1×10^(3)cm^(2)·V^(-1)·s^(-1),respectively.Especially,theμeof h-TiN_(2)amounts to 2.5×10^(4)cm^(2)·V^(-1)·s^(-1),and theμhof h-ZrN_(2)reaches to 7.7×10^(3)cm^(2)·V^(-1)·s^(-1).Importantly,unlike the MoS_(2)system,h-TMN_(2)forms Ohm contacts with both transition metals(e.g.,Cu)and 2D metals(e.g.,graphene),with tunneling possibilities exceeding 50%in the Cu system.These outstanding intrinsic semiconductor properties and contact characteristics exhibited by h-TMN_(2)highlight the immense potential of transition metal dinitrides in driving the advancement of next-generation information devices.Our findings significantly broaden the range of 2D materials and provide valuable insights for the development of high-eficiency 2D information devices. 展开更多
关键词 Two-dimensional(2D)materials Metal semiconductor contact Transition metal dinitrides 2D semiconductors First-principles calculations
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