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基于Cortex-M4内核的RT-Thread上下文切换机制剖析
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作者 徐丽华 王宜怀 奚圣鑫 《计算机应用与软件》 北大核心 2025年第1期213-216,302,共5页
RT-Thread是源码公开的国产嵌入式实时操作系统。基于Cortex-M4内核,对RT-Thread通过底层PendSV中断进行上下文切换的过程进行了剖析,从指令级别对上下文切换的实现机制进行了研究,为深入理解内核调度机制的实现提供了参考,也为RT-Threa... RT-Thread是源码公开的国产嵌入式实时操作系统。基于Cortex-M4内核,对RT-Thread通过底层PendSV中断进行上下文切换的过程进行了剖析,从指令级别对上下文切换的实现机制进行了研究,为深入理解内核调度机制的实现提供了参考,也为RT-Thread的应用与推广提供了技术基础。 展开更多
关键词 嵌入式实时操作系统 RT-thread 任务调度 上下文切换
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基于RT-Thread的实训室环境监测系统设计 被引量:1
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作者 范宏令 兰岚 刘霄 《山西电子技术》 2025年第1期35-37,66,共4页
实训室是职业院校进行实践教学和科研的重要场所,是改革校企合作模式、培养创新型复合人才和全面提高学生综合职业技能的重要支撑和保障,在职业教育中有着重要地位和作用,实训室安全直接关系着广大师生的生命财产安全,关系着学校和社会... 实训室是职业院校进行实践教学和科研的重要场所,是改革校企合作模式、培养创新型复合人才和全面提高学生综合职业技能的重要支撑和保障,在职业教育中有着重要地位和作用,实训室安全直接关系着广大师生的生命财产安全,关系着学校和社会的安全稳定。本文基于国产物联网操作系统RT-Thread,设计一款实训室环境监测系统,为实训室管理工作提供方便,保障广大师生的生命财产安全。 展开更多
关键词 环境监测 RT-thread NBIOT ZIGBEE 阿里云物联网平台
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Clinical observation on prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation 被引量:1
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作者 Yan-Mei Huang Dong Ouyang 《World Journal of Gastrointestinal Surgery》 2025年第1期209-216,共8页
BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different tre... BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different treatment options.AIM To analyze the clinical effect and prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation(RPH).METHODS A total of 100 patients with mixed hemorrhoids who visited our hospital from October 2022 to September 2023 were selected and randomly divided into the control group(n=50)and the treatment group(n=50)by rolling the dice.The procedure for prolapse and hemorrhoids(PPH)was adopted in the control group,while polidocanol foam injection+RPH was adopted in the treatment group.The therapeutic effects,operation time,wound healing time,hospital stay,pain situation(24 hours post-operative pain score,first defecation pain score),quality of life(QOL),incidence of complications(post-operative hemorrhage,edema,infection),incidence of anal stenosis 3 months post-operatively and recurrence rate 1 year post-operatively of the two groups were compared.RESULTS Compared with the control group,the total effective rate of treatment group was higher,and the difference was significant(P<0.05).The operation time/wound healing time/hospital stay in the treatment group were shorter than those in the control group(P<0.05).The pain scores at 24 hours after operation/first defecation pain score of the treatment group was significantly lower than those in the control group(P<0.05).After surgery,the QOL scores of the two groups decreased,with the treatment group having higher scores than that of the control group(P<0.05).Compared with the control group,the incidence of postoperative complications in the treatment group was lower,and the difference was significant(P<0.05);However,there was no significant difference in the incidence of postoperative bleeding between the two groups(P>0.05);There was no significant difference in the incidence of anal stenosis 3 months after operation and the recurrence rate 1 year after operation between the two groups(P>0.05).CONCLUSION For patients with mixed hemorrhoids,the therapeutic effect achieved by using polidocanol injection combined with RPH was better.The wounds of the patients healed faster,the postoperative pain was milder,QOL improved,and the incidence of complications was lower,and the short-term and long-term prognosis was good. 展开更多
关键词 Mixed hemorrhoids Polidocanol injection Automatic elastic thread ligation operation Postoperative hemorrhage The degree of pain Recurrent rate
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基于RT-Thread和STM32的多协议工业以太网控制系统设计
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作者 焦钰龙 陈华敏 《计算机应用文摘》 2025年第21期145-148,共4页
文章基于国产RT-Thread操作系统,构建了覆盖“芯片+操作系统+应用”的立体技术生态链。其采用模块化、可扩展架构设计,具备良好的跨硬件平台适应能力与多样化应用场景支持。在以太网协议移植过程中,文章通过集成RT-Thread底层网络驱动... 文章基于国产RT-Thread操作系统,构建了覆盖“芯片+操作系统+应用”的立体技术生态链。其采用模块化、可扩展架构设计,具备良好的跨硬件平台适应能力与多样化应用场景支持。在以太网协议移植过程中,文章通过集成RT-Thread底层网络驱动并配置相关网络组件,实现了稳定可靠的多TCP连接,完成了Modbus-TCP总线通信、FTP文件传输服务器及Web服务器的开发,最终设计并实现了基于RT-Thread与STM32的多协议工业以太网控制系统。该系统具有开发门槛低、设计周期短和成本低等特点,展现出良好的应用前景。 展开更多
关键词 嵌入式 RT-thread系统 工业以太网 LwIP栈 MODBUS总线
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基于RT-Thread的自平衡自行车系统
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作者 陈欣然 董玉华 +1 位作者 薛严冰 冯冲 《大连民族大学学报》 2025年第3期209-215,共7页
针对裸机模式下开发的自平衡自行车控制系统实时性差、开发周期长、缺乏可移植性等问题,设计了基于RT-Thread的自平衡自行车控制系统。系统以STM32F407为主控芯片,移植RT-Thread对系统软硬件资源进行分配管理,利用RT-Thread线程调度和... 针对裸机模式下开发的自平衡自行车控制系统实时性差、开发周期长、缺乏可移植性等问题,设计了基于RT-Thread的自平衡自行车控制系统。系统以STM32F407为主控芯片,移植RT-Thread对系统软硬件资源进行分配管理,利用RT-Thread线程调度和通信机制实现高实时性控制,同时设计调试辅助系统缩短系统开发周期。实验结果表明:车身在5°的初始状态下起摆可在2.15 s内回正至0°,静止状态车体摆幅在±0.4°,运动状态下车体摆幅不超过±3°,系统线程切换和线程抢占时间最大为10.1μs和12μs,证明该系统平衡控制稳定可靠,实时响应性能较高。 展开更多
关键词 RT-thread 串级PID Mahony互补滤波 微信小程序 OneNET
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Three-dimensional location approach with silk thread guided hepatectomy for liver tumor
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作者 Zhi-Hong Zhang Qing-Bo Feng +2 位作者 Chuang Jiang Ji-Wei Huang Jia-Xin Li 《World Journal of Gastroenterology》 2025年第8期66-71,共6页
BACKGROUND Intraoperative determination of resection margin and adequate residual liver parenchyma are the key points of hepatectomy for the treatment of liver tumors.Intraoperative ultrasound and indocyanine green fl... BACKGROUND Intraoperative determination of resection margin and adequate residual liver parenchyma are the key points of hepatectomy for the treatment of liver tumors.Intraoperative ultrasound and indocyanine green fluorescence navigation are the most commonly used methods at present,but the technical barriers limit their promotion.AIM To evaluate the value of the three-dimensional location approach with silk thread(3D-LAST)in precise resection of liver tumors.METHODS From September 2020 to January 2022,8 patients with liver tumors including hepatocellular carcinoma,intrahepatic cholangiocarcinoma,hilar cholangiocar-cinoma,and gastric cancer liver metastasis were included in this study.All patients underwent 3D-LAST in precise resection of liver tumors.RESULTS All patients(8/8,100%)underwent the operation successfully without any complications.During the mean follow-up of 8.7 months,all patients survived without tumor recurrence.CONCLUSION In conclusion,the 3D-LAST is a safe and effective new method for liver intraop-erative navigation,which is practical and easy to promote.Core Tip:The aim of this study is to evaluate the value of the three-dimensional location approach with silk thread(3D-LAST)in precise resection of liver tumors.Eight patients with liver tumors including hepatocellular carcinoma,intrahepatic cholangiocarcinoma,hilar cholangiocarcinoma,and gastric cancer liver metastasis underwent the operation successfully without any complications.During the mean follow-up of 8.7 months,all patients survived without tumor recurrence.In conclusion,the 3D-LAST is a safe and effective new method for liver intraoperative navigation,which is practical and easy to promote.INTRODUCTION Hepatectomy is widely used for the treatment of liver tumors.In recent decades,the concept and practice of hepatectomy have developed from irregular,regular and anatomical to the current precise resection.Necessary assistive technologies have enabled these advances.Intraoperative ultrasound(IOUS)localization and indocyanine green(ICG)fluorescence imaging guidance are two frequently-used approaches for laparoscopic hepatectomy[1,2].IOUS is an invaluable auxiliary means widely accepted in surgery for real-time diagnostic information to determine resection range and navigate the surgical path[3].However,the major limitation of IOUS is the time cost during the procedure for paging the sono-graphers and the difficulty of deciphering two dimensional images[4].ICG is a non-toxic water-soluble fluorophore that reveals fluorescence under the near-infrared spectrum[5].Since liver tissue penetration is limited to 5 to 10 mm,that restricted the visualization of deeper tumors by ICG excitation,thereby interfering with its application in laparoscopic hepatectomy[6].IOUS and ICG navigation require specific technical equipment,making implementation difficult in many centers.And these techniques will significantly increase the operation time.Three-dimensional(3D)visualization involves extracting features and producing volumetric images based on computed tomography(CT)through a computer postprocessing technique.This tool offers a reasonable approach to the clinical decision for the potential to display the complex internal anatomy in an intuitive and stereoscopic manner[7].In the past few decades,applying 3D simulation software for liver volume calculation,virtual simulation surgery,portal hypertension monitor,and surgical navigation has proven to be safe and effective[8].Therefore,we propose a new method to find obvious anatomical markers and calculate the resection range according to 3D positioning before operation.During the operation,the scope of resection was delineated with silk thread,and resection was performed.This is a new practical approach,which we named as 3D location approach with silk thread(3D-LAST).RESULTS During the study period from September 2020 to January 2022,5 patients with hepatocellular carcinoma,1 patient with intrahepatic cholangiocarcinoma,1 patient with hilar cholangiocarcinoma,and 1 patient with gastric cancer liver metastasis were assessed for liver resection.There were 5 males and 3 females.The mean age of these patients was 54.3±10.2 years(34-66 years).Preoperative 3D positioning was conducted and the scope of resection was delineated with a surgical suture successfully performed in all 8 patients without complications.The treatment results of these 8 patients are shown in Table 1.The 90-day operative mortality was zero.Complications worse than Dindo-Clavien IIIa was not observed at a mean follow-up time of 8.7 months(4-16 months),there was no evidence of tumor recurrence or extrahepatic metastasis.At the time of reporting,the patients are all alive and lead normal lives.We take one patient as an example,58-year-old male,who found a liver lesion 10 months after gastric cancer surgery.Enhanced CT showed that the lesion was located in the liver S5,about 1.5 cm in diameter,and considered metastatic lesions.We performed 3D-LAST guided hepatectomy on this patient(Figure 1).Other representative 3D-LAST surgical procedures are shown in Figure 2. 展开更多
关键词 HEPATECTOMY LAPAROSCOPY Liver tumor Three dimensional Silk thread
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Threads of Revival
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作者 HU FAN 《ChinAfrica》 2025年第9期31-33,共3页
When one steps inside Caoxian’s Youai Cloud Warehouse,a livestreaming base dedicated to hanfu,it feels less like a clothing warehouse and more like a time capsule.Thousands of intricately embroidered garments line th... When one steps inside Caoxian’s Youai Cloud Warehouse,a livestreaming base dedicated to hanfu,it feels less like a clothing warehouse and more like a time capsule.Thousands of intricately embroidered garments line the racks-from elegant horse-face skirts to modernised editions of traditional Chinese clothing. 展开更多
关键词 livestreaming base Caoxians Youai Cloud Warehouse clothing warehouse HANFU threadS intricately embroidered garments REVIVAL
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Research on the mechanism of high-performance gas sealing premium threaded connections
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作者 SUN Jian’an ZHANG Zhonghua GAO Zhan 《Baosteel Technical Research》 2025年第1期28-40,共13页
In petroleum extraction,the sealing surfaces of bolted joints are susceptible to damage due to the high-temperature and high-pressure conditions in wellbores.This damage adversely affects sealing performance,consequen... In petroleum extraction,the sealing surfaces of bolted joints are susceptible to damage due to the high-temperature and high-pressure conditions in wellbores.This damage adversely affects sealing performance,consequently leading to the failure and damage of threaded connections.In severe cases,it can result in considerable economic losses and trigger safety accidents.The sealing performance of special bolted joints holds crucial importance for production efficiency,output,equipment lifespan,and cost control.Enhancing the sealing perfor-mance of threaded connections can have a positive impact on industrial production and environmental protection.The existing research on American Petroleum Institute threaded joints has been thorough and has obtained a series of excellent results.However,the research on the sealing damage mechanism of threaded connections under complex well conditions lacks sufficient depth and that on new sealing technology is scarce.This study proposes a half-size evaluation test to address the abovementioned problem.Based on this test,an investigation into the sealing performance of threaded connections under high-temperature,cyclic loading,and high-temperature creep conditions is conducted.This study uses a combined approach of finite element methods and experiments to investigate the impact of different makeup torques on the sealing performance of premium threaded connections(PTCs).The results of the half-size evaluation test indicate that temperature notably influences the sealing performance of threaded connections.The continuous action of high temperatures causes contact pressure and sealing performance to decrease,and sealing contact pressure increases after cooling.Finite element and test results show that for a certain joint A,the greater the torque,the higher the critical sealing pressure of the thread,and the better the sealing performance.The research on the sealing damage mechanism of PTCs provides a scientific basis and theoretical guidance for the further optimization and development of PTCs. 展开更多
关键词 sealing performance premium threaded connection damage mechanism half-size evaluation test
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Small market but big potential:How sewing threads are weaving the future of automotive interiors and outdoor gear
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作者 Zhong Mengxia 《China Textile》 2025年第4期22-23,共2页
As the global textile market continues to expand, demand for sewing threads-a critical auxiliary material-is rising. In recent years, automotive interiors, smart outdoor equipment, and medical and ecofriendly products... As the global textile market continues to expand, demand for sewing threads-a critical auxiliary material-is rising. In recent years, automotive interiors, smart outdoor equipment, and medical and ecofriendly products have emerged as new growth engines for the textile industry. This has propelled specialized niche markets for sewing threads designed for these applications, revealing significant and undeniable potential. 展开更多
关键词 interiorssmart outdoor equipmentand automotive interiors smart outdoor equipment sewing threads eco friendly products textile industry medical products
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基于RT-Thread事件集的多线程相互同步设计方法研究
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作者 索明何 黄鑫 +2 位作者 王宜怀 施连敏 张建 《电脑与信息技术》 2025年第4期71-74,共4页
针对嵌入式系统设计中的多线程相互同步实现问题,提出基于实时操作系统事件集的一般设计算法,给出利用RT-Thread事件集的实现方法和应用实例,最后分析一般设计算法中存在的极端潜在风险,并加以改进,确保设计的可靠性。实践结果表明,所... 针对嵌入式系统设计中的多线程相互同步实现问题,提出基于实时操作系统事件集的一般设计算法,给出利用RT-Thread事件集的实现方法和应用实例,最后分析一般设计算法中存在的极端潜在风险,并加以改进,确保设计的可靠性。实践结果表明,所提出的设计方法具有很好的实时性和可靠性,并具有一定的通用性和参考价值。 展开更多
关键词 多线程相互同步 事件集 事件标志 可靠性
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基于RT-Thread的液压支架监控分站的设计
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作者 王磊 付晨妍 齐俊艳 《煤炭技术》 CAS 2024年第3期250-254,共5页
为提高煤矿生产的安全性和效率,降低生产成本,设计了基于嵌入式实时操作系统RT-Thread的液压支架监控分站。该分站通过CAN总线将综采工作面液压支架的工作数据上传到主站并接收主站下达的指令;此外,通过支架控制器可以实现对液压支架的... 为提高煤矿生产的安全性和效率,降低生产成本,设计了基于嵌入式实时操作系统RT-Thread的液压支架监控分站。该分站通过CAN总线将综采工作面液压支架的工作数据上传到主站并接收主站下达的指令;此外,通过支架控制器可以实现对液压支架的远程控制。软件设计利用信号量和事件集进行线程间通信同步;同时采用多线程优先级抢占调度机制,实现任务的并发运行。实验证明,该分站具有精度高、可靠性强和实时响应等特点,达到工程实际应用需求。 展开更多
关键词 RT-thread STM32 液压支架 监控分站 卡尔曼滤波
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基于RT-thread的精确时间同步系统设计 被引量:3
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作者 高中淦 岳凤英 +1 位作者 王恩怀 赵田娟 《国外电子测量技术》 2024年第3期114-120,共7页
分布式智能采集终端需要一致的时间基准,用于多种数据和事件的时间标记。为满足智能采集终端对高精度时间同步的需求,选择IEEE 1588精确时间同步协议实现时间同步;设计基于纯国产32 bit双核微控制器HPM6750和以太网收发器RTL8211FS(I)-V... 分布式智能采集终端需要一致的时间基准,用于多种数据和事件的时间标记。为满足智能采集终端对高精度时间同步的需求,选择IEEE 1588精确时间同步协议实现时间同步;设计基于纯国产32 bit双核微控制器HPM6750和以太网收发器RTL8211FS(I)-VS的精确时间同步系统,选用国产开源嵌入式实时操作系统RT-thread操作系统,实现在物理层获取时间戳来运行IEEE 1588协议;构建测试平台对该时间同步系统进行主从时钟同步精度测试。测试结果表明,设计在物理层获取时间戳时达到的时间同步精度在±250 ns以内,与在数据链路层获取时间戳时达到±10μs的时间同步精度相比较,有效提高了时间同步精度,可广泛应用于对时间同步精度有较高要求的智能采集终端。 展开更多
关键词 采集终端 IEEE 1588 时间同步 实时操作系统 RT-thread 国产化
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基于RT-Thread的可信软件栈的设计和实现 被引量:1
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作者 刘栋 王东辉 《电子设计工程》 2024年第2期51-55,共5页
针对基于Linux和TCG软件栈(Trusted computing group Software Stack,TSS)的复杂性问题,提出一种轻量级的可信软件栈。分析了TSS的基本结构与TSS在嵌入式系统的局限,总结出基于嵌入式系统的可信软件栈设计需求,设计出软件栈命令调用的... 针对基于Linux和TCG软件栈(Trusted computing group Software Stack,TSS)的复杂性问题,提出一种轻量级的可信软件栈。分析了TSS的基本结构与TSS在嵌入式系统的局限,总结出基于嵌入式系统的可信软件栈设计需求,设计出软件栈命令调用的机制和软件栈的结构。此外,分析了TSS密钥管理缓存算法,在flash中定义一块密钥槽空间,方便密钥管理中直接访问,阐述密钥生成的逻辑过程,实现面向嵌入式系统的可信软件系统。经实验验证,该软件栈可以结合RT-Thread实时系统实现基本的可信计算功能。 展开更多
关键词 可信软件栈 密钥管理 缓存算法 RT-thread
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Preload Control Method of Threaded Fasteners:A Review
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作者 Xing Yan Zhifeng Liu +3 位作者 Mingpo Zheng Ying Li Yuezhen Wang Wentao Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第5期40-59,共20页
Threaded fasteners are one of the most commonly used connection methods for mechanical structures.Its primary function is to generate appropriate clamping forces and fasten the connected parts.An inappropriate preload... Threaded fasteners are one of the most commonly used connection methods for mechanical structures.Its primary function is to generate appropriate clamping forces and fasten the connected parts.An inappropriate preload can cause loosening,fatigue fracture,and other problems.This will affect the safety and reliability of mechanical equipment.The precise control of the preload has become a critical issue in mechanical assembly processes.Over the past few decades,various tightening measures and methods have been proposed to address this issue.However,many problems continue to exist with practical applications that have not been reviewed comprehensively and systematically.First,various control methods were summarized systematically,and their advantages and disadvantages in engineering applications were analyzed.Torque control is the most widely used tightening method owing to its simple operation and low cost.Therefore,the research on the torque control method was summarized systematically from three aspects:the torque-preload correlation formula,effective friction radius,and friction characteristics during tightening.In addition,the special circumstances that may increase preload uncertainty were discussed.Finally,based on a summary of the current research status,the prospects for future research were discussed.This study would aid researchers in extensively understanding the problems in preload control. 展开更多
关键词 threaded fasteners PRELOAD Tightening method Torque control method Friction characteristics
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一种基于RT-Thread的室内环境监测系统设计 被引量:3
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作者 李楷文 潘启勇 《工业控制计算机》 2024年第12期140-141,144,共3页
为了提高传统环境监测系统多任务协调与实时性的水平,设计了一款以STM32F103ZET6微控制器为核心的监测系统。该系统利用RT-Thread实时操作系统来进行多任务调度,实现温湿度、空气质量、光照强度等参数的采集,并通过窄带物联网上传至阿... 为了提高传统环境监测系统多任务协调与实时性的水平,设计了一款以STM32F103ZET6微控制器为核心的监测系统。该系统利用RT-Thread实时操作系统来进行多任务调度,实现温湿度、空气质量、光照强度等参数的采集,并通过窄带物联网上传至阿里云平台进行观测。经测试,监测温度误差不超过0.5℃,空气质量误差小于2%,检测时间低于0.5秒,相较于传统监测系统实时性更好。 展开更多
关键词 操作系统 RT-thread 窄带物联网 阿里云 实时监测
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基于RT-Thread多线程程序的可穿戴心理健康监测设备设计研究 被引量:1
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作者 陈桃放 《自动化与仪器仪表》 2024年第5期227-231,236,共6页
为了实现个体心理健康的长期监测,获得客观评估心理状况的实时数据,研究设计了一款采集用户语音、行为以及环境数据的可穿戴设备,并借助主成分分析特征压缩法与集成思想完成心理健康的评估。实验结果表明,合成加速度的时域幅值方差值和... 为了实现个体心理健康的长期监测,获得客观评估心理状况的实时数据,研究设计了一款采集用户语音、行为以及环境数据的可穿戴设备,并借助主成分分析特征压缩法与集成思想完成心理健康的评估。实验结果表明,合成加速度的时域幅值方差值和第二共振峰特征值分布情况可有效区分心理健康状态。量表低分测试者的方差值分布相对集中,密度曲线在1 000 Hz~3 500 Hz范围内呈现高斯分布,与受试者心理健康状态实际情况相符。研究设计的决策分类模型准确率较高,均方根误差收敛于0.563,召回率较高,模型综合性能较优。此次研究设计的可穿戴心理健康监测设备能够长期有效监测用户行为数据,提供了便捷、客观、综合和个性化的心理健康管理方式。 展开更多
关键词 RT-thread多线程程序 语音特征值 低频数据特征值 主成分分析 皮尔逊相关系数
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Dental Precautions for the Golden Thread Lift Procedure
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作者 Toshiyuki Inou Keiko Kaneko +8 位作者 Tatsuo Takaya Toshinobu Tsumura Emi Oki Yu Chi Hung Takuya Iwasaki Toru Kageyama Zeng Bo Zhao Yoshimi Kawahara Keiichi Uchida 《Open Journal of Stomatology》 2024年第11期433-439,共7页
In cosmetic surgery, golden threads have been used in thread lift procedures, wherein golden threads are placed under the skin of the neck and chin. These are mainly applied in the maxillofacial region adjacent to the... In cosmetic surgery, golden threads have been used in thread lift procedures, wherein golden threads are placed under the skin of the neck and chin. These are mainly applied in the maxillofacial region adjacent to the sites of dental treatment to achieve cosmetic benefits. However, as dentists typically lack sufficient knowledge about the golden thread lift procedure, it may present a challenge to dental examinations and treatments. It is therefore crucial for dentists to have a comprehensive understanding of the procedure. This case report covers our experience with the dental examination of a patient with golden threads. We emphasize the dental complications and precautions that should be taken for such cases. These golden threads are made of pure gold, nonabsorbable, and can be broken. These can obstruct dental examination, as well as cause metal allergies and foreign body granulomas. Additionally, it is difficult to completely remove these threads when they break apart. In the future, since more patients are expected to undergo this procedure, it is possible to encounter these golden threads as artifacts on imaging. Therefore, it is important to educate dentists about the golden thread lift procedure and its dental implications. It is also imperative to determine whether the patient has undergone the golden thread lift procedure in the medical questionnaire prior to the magnetic resonance imaging examination. Thus, dentists should be able to conduct a detailed interview with the patient, determine the feasibility of examination or treatment, and communicate this assessment to the patient. 展开更多
关键词 Golden threads Computed Tomography Magnetic Resonance Imaging Metal Allergy Foreign Body Granuloma
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基于 RT-Thread 的玉米对行收获控制系统 研发与测试
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作者 郭佳炜 王骞 +3 位作者 尚业华 秦五昌 王锋 吕昊暾 《中国农机化学报》 北大核心 2024年第11期28-34,共7页
为提高玉米机械化收获效率,减轻驾驶员劳动强度,研发玉米收获对行控制系统。该系统包括玉米边界行感知模块和对行控制模块,采用激光雷达获取玉米行点云数据,提出基于STM32处理器和RT-Thread实时操作系统的点云数据快速分析处理方法,实... 为提高玉米机械化收获效率,减轻驾驶员劳动强度,研发玉米收获对行控制系统。该系统包括玉米边界行感知模块和对行控制模块,采用激光雷达获取玉米行点云数据,提出基于STM32处理器和RT-Thread实时操作系统的点云数据快速分析处理方法,实现玉米行边界点的提取,通过边界点计算得到横向偏差;设计系统通信拓扑架构,实现感知、处理、对行控制模块之间的高效通信。对该系统的性能开展田间试验验证,结果表明:收割机与玉米行实际边界线的平均横向偏差为0.06 m,最大横向偏差为0.126 m,满足玉米对行收获作业要求,为玉米对行收获提供一定的参考。 展开更多
关键词 玉米对行收获 控制系统 RT-thread 激光雷达 单片机 点云数据
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基于RT-Thread的卫星导航控制系统研究
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作者 宋丽 鲁海宁 +2 位作者 孙崇书 宋涛 宋建平 《农机使用与维修》 2024年第12期17-23,共7页
随着制造业的发展,自动引导车被广泛应用于现代工业领域,由于作业环境复杂程度变高,对车辆控制系统硬件的稳定性、灵活性,软件系统的实时性、模块化程度有了更高要求。从自动引导车的需求出发,对导航控制系统的硬件及软件进行了设计,后... 随着制造业的发展,自动引导车被广泛应用于现代工业领域,由于作业环境复杂程度变高,对车辆控制系统硬件的稳定性、灵活性,软件系统的实时性、模块化程度有了更高要求。从自动引导车的需求出发,对导航控制系统的硬件及软件进行了设计,后针对路径规划与路径追踪模块,提出了一种路径规划与追踪控制方法,通过输入不同的横向误差与速度进行指定模糊规则,最终得到合适的预瞄距离,从而使车辆实现自适应预瞄距离的功能,提高车辆的自适应能力。试验结果证明了设计的可行性,为后续自动引导车的控制系统研究提供参考。 展开更多
关键词 RT-thread GNSS AGV 控制系统 模糊控制
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Roller Screw and Threaded Chain Speed Reducer: An Experimental Evaluation
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作者 Filiberto Gutiérrez 《Modern Mechanical Engineering》 2024年第1期1-11,共11页
We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuratio... We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46. 展开更多
关键词 Speed Reducer Inverted Roller Screw Chain Drive threaded Chain Drive
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