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Efficient computation of Hash Hirschberg protein alignment utilizing hyper threading multi-core sharing technology
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作者 Muhannad Abu-Hashem Adnan Gutub 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第2期278-291,共14页
Due to current technology enhancement,molecular databases have exponentially grown requesting faster efficient methods that can handle these amounts of huge data.There-fore,Multi-processing CPUs technology can be used... Due to current technology enhancement,molecular databases have exponentially grown requesting faster efficient methods that can handle these amounts of huge data.There-fore,Multi-processing CPUs technology can be used including physical and logical processors(Hyper Threading)to significantly increase the performance of computations.Accordingly,sequence comparison and pairwise alignment were both found contributing significantly in calculating the resemblance between sequences for constructing optimal alignments.This research used the Hash Table-NGram-Hirschberg(HT-NGH)algo-rithm to represent this pairwise alignment utilizing hashing capabilities.The authors propose using parallel shared memory architecture via Hyper Threading to improve the performance of molecular dataset protein pairwise alignment.The proposed parallel hyper threading method targeted the transformation of the HT-NGH on the datasets decomposition for sequence level efficient utilization within the processing units,that is,reducing idle processing unit situations.The authors combined hyper threading within the multicore architecture processing on shared memory utilization remarking perfor-mance of 24.8%average speed up to 34.4%as the highest boosting rate.The benefit of this work improvement is shown preserving acceptable accuracy,that is,reaching 2.08,2.88,and 3.87 boost-up as well as the efficiency of 1.04,0.96,and 0.97,using 2,3,and 4 cores,respectively,as attractive remarkable results. 展开更多
关键词 computational biology high-performance computing Hyper threading pairwise sequence alignment parallel design sequence alignment SHARED-MEMORY
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Threads of Revival
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作者 HU FAN 《China Today》 2026年第1期50-51,共2页
E-commerce has transformed Caoxian into a hub of traditional Chinese attire.STEPPING inside Caoxian’s Youai Cloud Warehouse,a livestreaming base dedicated to hanfu(traditional clothing),it feels less like a clothing ... E-commerce has transformed Caoxian into a hub of traditional Chinese attire.STEPPING inside Caoxian’s Youai Cloud Warehouse,a livestreaming base dedicated to hanfu(traditional clothing),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 clothing warehouse HANFU livestreaming caoxian threads revival youai cloud warehousea e commerce
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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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Adaptive threading strategy based on rolling characteristics analysis in hot strip rolling 被引量:2
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作者 PENG Wen CHEN Shu-zong +2 位作者 GONG Dian-yao LIU Zi-ying ZHANG Dian-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第7期1560-1572,共13页
In order to improve the threading stability and the head thickness precision in tandem hot rolling process, an adaptive threading strategy was proposed. The proposed strategy was realized by the rolling characteristic... In order to improve the threading stability and the head thickness precision in tandem hot rolling process, an adaptive threading strategy was proposed. The proposed strategy was realized by the rolling characteristics analysis, and factors which affect the rolling force and the final thickness were determined and analyzed based on the influence coefficients calculation process. An objective function consisting of the influenced factors was founded, and the disturbance quantity was obtained by minimizing the function with the Nelder-Mead simplex method, and the proposed adaptive threading strategy was realized based on the calculation results. The adaptive threading strategy has been applied to one 7-stand hot tandem mill successfully, actual statistics data show that the predicted rolling force prediction in the range of +/- 5.0% is improved to 97.8%, the head thickness precision in the range of +/- 35 mu m is improved to 98.5%, and the threading stability and the head thickness precision are enhanced to a high level. 展开更多
关键词 hot strip ROLLING ADAPTIVE threading ROLLING characteristics ANALYSIS influence COEFFICIENTS method SIMPLEX algorithm
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Application of Adaptive Threading Technique to Hot Strip Mill 被引量:2
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作者 DING Jing-guo HU Xian-lei +2 位作者 JIAO Jing-min SHE Guang-fu LIU Xiang-hua 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2008年第5期29-31,36,共4页
Thickness deviation of hot strip rolling needs to be strictly controlled in the computer system. An adaptive threading technique was researched, in which the measured data from threaded stands were used to predict thi... Thickness deviation of hot strip rolling needs to be strictly controlled in the computer system. An adaptive threading technique was researched, in which the measured data from threaded stands were used to predict thickness and material hardness errors, to modify the setup for the remaining unthreaded stands. After the adaptive threading model was used online on the hot strip mill of the Panzhihua Iron and Steel Group Co Ltd, the thickness deviation was decreased obviously. The hit rate of thickness control of different steel grades increases. 展开更多
关键词 hot strip mill adaptive threading thickness deviation stretch equation
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Evaluation of threading dislocation density of strained Ge epitaxial layer by high resolution x-ray diffraction 被引量:1
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作者 苗渊浩 胡辉勇 +3 位作者 李鑫 宋建军 宣荣喜 张鹤鸣 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期511-515,共5页
The analysis of threading dislocation density (TDD) in Ge-on-Si layer is critical for developing lasers, light emitting diodes (LEDs), photodetectors (PDs), modulators, waveguides, metal oxide semiconductor fiel... The analysis of threading dislocation density (TDD) in Ge-on-Si layer is critical for developing lasers, light emitting diodes (LEDs), photodetectors (PDs), modulators, waveguides, metal oxide semiconductor field effect transistors (MOSFETs), and also the integration of Si-based monolithic photonics. The TDD of Ge epitaxial layer is analyzed by etching or transmission electron microscope (TEM). However, high-resolution x-ray diffraction (HR-XRD) rocking curve provides an optional method to analyze the TDD in Ge layer. The theory model of TDD measurement from rocking curves was first used in zinc-blende semiconductors. In this paper, this method is extended to the case of strained Ge-on-Si layers. The HR-XRD 2θ/ω scan is measured and Ge (004) single crystal rocking curve is utilized to calculate the TDD in strained Ge epitaxial layer. The rocking curve full width at half maximum (FWHM) broadening by incident beam divergence of the instrument, crystal size, and curvature of the crystal specimen is subtracted. The TDDs of samples A and B are calculated to be 1.41108 cm-2 and 6.47108 cm-2, respectively. In addition, we believe the TDDs calculated by this method to be the averaged dislocation density in the Ge epitaxial layer. 展开更多
关键词 HR-XRD RPCVD threading dislocation density (TDD) etching pit density (EPD)
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Electronic and optical properties of GaN/AlN quantum dots with adjacent threading dislocations
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作者 叶寒 芦鹏飞 +4 位作者 俞重远 姚文杰 陈智辉 贾博雍 刘玉敏 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期375-380,共6页
We present a theory to simulate a coherent GaN QD with an adjacent pure edge threading dislocation by using a finite element method. The piezoelectric effects and the strain modified band edges are investigated in the... We present a theory to simulate a coherent GaN QD with an adjacent pure edge threading dislocation by using a finite element method. The piezoelectric effects and the strain modified band edges are investigated in the framework of multi-band κ · p theory to calculate the electron and the heavy hole energy levels. The linear optical absorption coefficients corresponding to the interband ground state transition are obtained via the density matrix approach and perturbation expansion method. The results indicate that the strain distribution of the threading dislocation affects the electronic structure. Moreover, the ground state transition behaviour is also influenced by the position of the adjacent threading dislocation. 展开更多
关键词 quantum dot threading dislocation electronic structure absorption efficiency
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Simultaneous Multithreading Fault Tolerance Processor
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作者 DONGLan HUMing-zeng +3 位作者 JIZhen-zhou CUIGuang-zuo TANGXin-min HEFeng 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第1期17-20,共4页
Transient fault detection mechanism is added to simultaneous multithreading architecture. By exploiting both ILP (Instruction Level Parallelism) and TLP (Thread Level Parallelism), Simultaneous Multithreading (SMT) Fa... Transient fault detection mechanism is added to simultaneous multithreading architecture. By exploiting both ILP (Instruction Level Parallelism) and TLP (Thread Level Parallelism), Simultaneous Multithreading (SMT) Fault Tolerance Processor can be expected to achieve better tradeoff between performance and hardware cost than traditional Fault Tolerance Processors. Detailed simulations of 3 of SPEC95 benchmarks show that executing two redundant programs on the fault-tolerant microarchitecture takes only 40%–61%longer than running a single version of the program. The new instruction fetch algorithm enhances the performance by 0.4%~1%to most of the benchmarks we choose randomly. 展开更多
关键词 Key words simultaneous multithreading rault tolerance TLP (thread Level Parallelism) fetch policy
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An HLA/RTI Architecture Based on Multi-thread Processing 被引量:1
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作者 管莉 邹汝平 +1 位作者 朱斌 郝重阳 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第3期182-188,共7页
In order to improve the real-time performance of the real-time HLA(high level architecture) in the application of massive data communication volume,multi-thread processing was adopted,thread pool structure was introdu... In order to improve the real-time performance of the real-time HLA(high level architecture) in the application of massive data communication volume,multi-thread processing was adopted,thread pool structure was introduced into the system,different threads to handle corresponding message queues was utilized to respond different message requests.Furthermore,an allocation strategy of semi-complete deprivation of priority was adopted,which reduces thread switching cost and processing burden in the system,provided that the message requests with high priority can be responded in time,thus improves the system's overall performance.The design and experiment results indicate that the method proposed in this paper can improve the real-time performance of HLA in distributed system applications greatly. 展开更多
关键词 computer application HLA/RTI multi-thread distributed interactive simulation system
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Multi-threaded Fast Distance Field Computation Using Spatial Partition 被引量:2
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作者 MIN De-heng JIA Shi-yu ZHANG Xiao-yun 《科技视界》 2015年第8期153-154,共2页
This article describes three algorithms for distance field generation on triangulated model: brute force algorithm, single-threaded algorithm based on spatial partition and multi-threaded algorithm based on spatial pa... This article describes three algorithms for distance field generation on triangulated model: brute force algorithm, single-threaded algorithm based on spatial partition and multi-threaded algorithm based on spatial partition. Spatial partition algorithm use equidistant network divide the bounding box into equal-sized cubes, calculates the maximum and minimum distances between the sample point and each of the small cubes,taking the minimum value from the maximum distance as the minimum distance from the sample point to the model named d1, comparing d1 with the distance from sample point to every little cube's minimum distance d2, if d1 <d2, the sample point's distance to all triangles inside this cube are greater than d1, skip this cube, otherwise, calculated the distance from the point to all the triangles intersect with the cube, then alternative d1 with the minimum value, circulate all small cubes intersect with the model. Comparing the calculation results, it can be seen that the algorithm about the multi-threaded distance field relative to the other two algorithms in computational speed is greatly improved especially for complex models. 展开更多
关键词 三角模型 计算方法 空间划分 单线程
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Numerical investigation on threading dislocation bending with InAs/GaAs quantum dots
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作者 Guo-Feng Wu Jun Wang +8 位作者 Wei-Rong Chen Li-Na Zhu Yuan-Qing Yang Jia-Chen Li Chun-Yang Xiao Yong-Qing Huang Xiao-Min Ren Hai-Ming Ji Shuai Luo 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第11期146-150,共5页
The threading dislocations(TDs)in GaAs/Si epitaxial layers due to the lattice mismatch seriously degrade the performance of the lasers grown on silicon.The insertion of InAs quantum dots(QDs)acting as dislocation filt... The threading dislocations(TDs)in GaAs/Si epitaxial layers due to the lattice mismatch seriously degrade the performance of the lasers grown on silicon.The insertion of InAs quantum dots(QDs)acting as dislocation filters is a pretty good alternative to solving this problem.In this paper,a finite element method(FEM)is proposed to calculate the critical condition for InAs/GaAs QDs bending TDs into interfacial misfit dislocations(MDs).Making a comparison of elastic strain energy between the two isolated systems,a reasonable result is obtained.The effect of the cap layer thickness and the base width of QDs on TD bending are studied,and the results show that the bending area ratio of single QD(the bending area divided by the area of the QD base)is evidently affected by the two factors.Moreover,we present a method to evaluate the bending capability of single-layer QDs and multi-layer QDs.For the QD with 24-nm base width and 5-nm cap layer thickness,taking the QD density of 10^(11) cm^(-2) into account,the bending area ratio of single-layer QDs(the area of bending TD divided by the area of QD layer)is about 38.71%.With inserting five-layer InAs QDs,the TD density decreases by 91.35%.The results offer the guidelines for designing the QD dislocation filters and provide an important step towards realizing the photonic integration circuits on silicon. 展开更多
关键词 InAs/GaAs quantum dots threading dislocation finite element method bending area
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Design of cable tester based on multi-thread parallel testing technology
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作者 WEN feng YUAN Xiao hang +2 位作者 DING Zhi zhao WANG Xiao li ZHEN Guo yong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第3期214-218,共5页
In order to realize the efficiency, reliability and safety tests on the complex cable network of an electronic system, an efficient cable network resistance tester is designed. Firstly, the design background and hardw... In order to realize the efficiency, reliability and safety tests on the complex cable network of an electronic system, an efficient cable network resistance tester is designed. Firstly, the design background and hardware structure are briefly described. Then aiming at the multi task parallelism considering real time measurement of parameters and real time control of the system in the tester testing, a real time muhi task control software is developed by using multi thread testing technology in parallel test to realize multi task complex control. Finally, the least squares method is used to improve the test accuracyof the tester. The test results show that the test error is basically within 0.3%, and the test speed can reach 345 point/min. 展开更多
关键词 cable tester multi thread parallel least square method
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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:4
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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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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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Dynamically Translating Binary Code for Multi-Threaded Programs Using Shared Code Cache
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作者 Chia-Lun Liu Jiunn-Yeu Chen +1 位作者 Wuu Yang Wei-Chung Hsu 《Journal of Electronic Science and Technology》 CAS 2014年第4期434-438,共5页
mc211vm is a process-level ARM-to-x86 binary translator developed in our lab in the past several years. Currently, it is able to emulate singlethreaded programs. We extend mc211vm to emulate multi-threaded programs. O... mc211vm is a process-level ARM-to-x86 binary translator developed in our lab in the past several years. Currently, it is able to emulate singlethreaded programs. We extend mc211vm to emulate multi-threaded programs. Our main task is to reconstruct its architecture for multi-threaded programs. Register mapping, code cache management, and address mapping in mc2llvm have all been modified. In addition, to further speed up the emulation, we collect hot paths, aggressively optimize and generate code for them at run time. Additional threads are used to alleviate the overhead. Thus, when the same hot path is walked through again, the corresponding optimized native code will be executed instead. In our experiments, our system is 8.8X faster than QEMU (quick emulator) on average when emulating the specified benchmarks with 8 vip threads. 展开更多
关键词 ARM binary translation hot path mc211vm multi-threaded program QEMU (quickemulator).
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An Approach of Branch Multithreading Switch Mechanism
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作者 Lan Dong Zhenzhou Ji Mingzeng Hu Xinmin Tang 《通讯和计算机(中英文版)》 2006年第5期14-16,39,共4页
关键词 解码器 多线程 调节装置 计算机技术
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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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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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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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