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P4LoF: Scheduling Loop-Free Multi-Flow Updates in Programmable Networks
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作者 Jiqiang Xia Qi Zhan +2 位作者 Le Tian Yuxiang Hu Jianhua Peng 《Computers, Materials & Continua》 2026年第1期1236-1254,共19页
The rapid growth of distributed data-centric applications and AI workloads increases demand for low-latency,high-throughput communication,necessitating frequent and flexible updates to network routing configurations.H... The rapid growth of distributed data-centric applications and AI workloads increases demand for low-latency,high-throughput communication,necessitating frequent and flexible updates to network routing configurations.However,maintaining consistent forwarding states during these updates is challenging,particularly when rerouting multiple flows simultaneously.Existing approaches pay little attention to multi-flow update,where improper update sequences across data plane nodes may construct deadlock dependencies.Moreover,these methods typically involve excessive control-data plane interactions,incurring significant resource overhead and performance degradation.This paper presents P4LoF,an efficient loop-free update approach that enables the controller to reroute multiple flows through minimal interactions.P4LoF first utilizes a greedy-based algorithm to generate the shortest update dependency chain for the single-flow update.These chains are then dynamically merged into a dependency graph and resolved as a Shortest Common Super-sequence(SCS)problem to produce the update sequence of multi-flow update.To address deadlock dependencies in multi-flow updates,P4LoF builds a deadlock-fix forwarding model that leverages the flexible packet processing capabilities of the programmable data plane.Experimental results show that P4LoF reduces control-data plane interactions by at least 32.6%with modest overhead,while effectively guaranteeing loop-free consistency. 展开更多
关键词 Network management update consistency programmable data plane P4
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Application of a Typhoon Initialization Scheme Based on the Incremental Analysis Updates Technique in a Rapid Update Cycle System 被引量:2
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作者 CHEN Feng DONG Mei-ying +1 位作者 JI Chun-xiao QIU Jin-jing 《Journal of Tropical Meteorology》 SCIE 2020年第4期428-440,共13页
Initialization of tropical cyclones plays an important role in typhoon numerical prediction. This study applied a typhoon initialization scheme based on the incremental analysis updates (IAU) technique in a rapid refr... Initialization of tropical cyclones plays an important role in typhoon numerical prediction. This study applied a typhoon initialization scheme based on the incremental analysis updates (IAU) technique in a rapid refresh system to improve the prediction of Typhoon Lekima (2019). Two numerical sensitivity experiments with or without application of the IAU technique after performing vortex relocation and wind adjustment procedures were conducted for comparison with the control experiment, which did not involve a typhoon initialization scheme. Analysis of the initial fields indicated that the relocation procedure shifted the typhoon circulation to the observed typhoon region, and the wind speeds became closer to the observations following the wind adjustment procedure. Comparison of the results of the sensitivity and control experiments revealed that the vortex relocation and wind adjustment procedures could improve the prediction of typhoon track and intensity in the first 6-h period, and that these improvements were extended throughout the first 12-h period of the prediction by the IAU technique. The new typhoon initialization scheme also improved the simulated typhoon structure in terms of not only the wind speed and warm core prediction but also the organization of the eye of Typhoon Lekima. Diagnosis of the tendencies of variables showed that use of the IAU technique in a typhoon initialization scheme is efficacious in resolving the spurious high-frequency noise problem such that the model is able to reach equilibrium as soon as possible. 展开更多
关键词 typhoon initialization vortex relocation incremental analysis updates numerical simulation Lekima
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Health Data Availability Protection:Delta-XOR-Relay Data Update in Erasure-Coded Cloud Storage Systems
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作者 Yifei Xiao Shijie Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期169-185,共17页
To achieve the high availability of health data in erasure-coded cloud storage systems,the data update performance in erasure coding should be continuously optimized.However,the data update performance is often bottle... To achieve the high availability of health data in erasure-coded cloud storage systems,the data update performance in erasure coding should be continuously optimized.However,the data update performance is often bottlenecked by the constrained cross-rack bandwidth.Various techniques have been proposed in the literature to improve network bandwidth efficiency,including delta transmission,relay,and batch update.These techniques were largely proposed individually previously,and in this work,we seek to use them jointly.To mitigate the cross-rack update traffic,we propose DXR-DU which builds on four valuable techniques:(i)delta transmission,(ii)XOR-based data update,(iii)relay,and(iv)batch update.Meanwhile,we offer two selective update approaches:1)data-deltabased update,and 2)parity-delta-based update.The proposed DXR-DU is evaluated via trace-driven local testbed experiments.Comprehensive experiments show that DXR-DU can significantly improve data update throughput while mitigating the cross-rack update traffic. 展开更多
关键词 Data availability health data data update cloud storage IoT
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System Reliability Analysis for Truss Structures Based on Automatic Updated Model
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作者 Pengyu Chen Cunbao Zhao +1 位作者 He Yao Junliang Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期2057-2071,共15页
Multiple failure modes tend to be identified in the reliability analysis of a redundant truss structure.This identification process involves updating the model for identifying the next potential failure members.Herein... Multiple failure modes tend to be identified in the reliability analysis of a redundant truss structure.This identification process involves updating the model for identifying the next potential failure members.Herein we intend to update the finite element model automatically in the identification process of failure modes and further perform the system reliability analysis efficiently.This study presents a framework that is implemented through the joint simulation of MATLAB and APDL and consists of three parts:reliability index of a single member,identification of dominant failure modes,and system-level reliability analysis for system reliability analysis of truss structures.Firstly,RSM(response surface method)combines with a constrained optimization model to calculate the reliability indices ofmembers.Then theβ-unzipping method is adopted to identify the dominant failuremodes,and the system function in MATLAB,as well as the EKILL command in APDL,is used to facilitate the automatic update of the finite element model and realize load-redistribution.Besides,the differential equivalence recursion algorithmis performed to approximate the reliability indices of failuremodes efficiently and accurately.Eventually,the PNET(probabilistic network evaluation technique)is used to calculate the joint failure probability as well as the system reliability index.Two illustrative examples demonstrate the accuracy and efficiency of the proposed system reliability analysis framework through comparison with corresponding references. 展开更多
关键词 Multiple failure modes truss structure automatic update system reliability analysis framework
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A New Encryption Mechanism Supporting the Update of Encrypted Data for Secure and Efficient Collaboration in the Cloud Environment
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作者 Chanhyeong Cho Byeori Kim +1 位作者 Haehyun Cho Taek-Young Youn 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期813-834,共22页
With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly increased.However,traditional collaboration tools primarily rely on access control,leaving data stored on cloud... With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly increased.However,traditional collaboration tools primarily rely on access control,leaving data stored on cloud servers vulnerable due to insufficient encryption.This paper introduces a novel mechanism that encrypts data in‘bundle’units,designed to meet the dual requirements of efficiency and security for frequently updated collaborative data.Each bundle includes updated information,allowing only the updated portions to be reencrypted when changes occur.The encryption method proposed in this paper addresses the inefficiencies of traditional encryption modes,such as Cipher Block Chaining(CBC)and Counter(CTR),which require decrypting and re-encrypting the entire dataset whenever updates occur.The proposed method leverages update-specific information embedded within data bundles and metadata that maps the relationship between these bundles and the plaintext data.By utilizing this information,the method accurately identifies the modified portions and applies algorithms to selectively re-encrypt only those sections.This approach significantly enhances the efficiency of data updates while maintaining high performance,particularly in large-scale data environments.To validate this approach,we conducted experiments measuring execution time as both the size of the modified data and the total dataset size varied.Results show that the proposed method significantly outperforms CBC and CTR modes in execution speed,with greater performance gains as data size increases.Additionally,our security evaluation confirms that this method provides robust protection against both passive and active attacks. 展开更多
关键词 Cloud collaboration mode of operation data update efficiency
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An improved fluid flow algorithm for hydraulic fracturing:Optimizing domain volume and crack pressure update strategies
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作者 Wei Zhang Jing Bi +3 位作者 Yu Zhao Yongfa Zhang Chaolin Wang Yang Pan 《International Journal of Mining Science and Technology》 2025年第4期639-657,共19页
With the widespread adoption of hydraulic fracturing technology in oil and gas resource development,improving the accuracy and efficiency of fracturing simulations has become a critical research focus.This paper propo... With the widespread adoption of hydraulic fracturing technology in oil and gas resource development,improving the accuracy and efficiency of fracturing simulations has become a critical research focus.This paper proposes an improved fluid flow algorithm,aiming to enhance the computational efficiency of hydraulic fracturing simulations while ensuring computational accuracy.The algorithm optimizes the aperture law and iteration criteria,focusing on improving the domain volume and crack pressure update strategy,thereby enabling precise capture of dynamic borehole pressure variations during injection tests.The effectiveness of the algorithm is verified through three flow-solid coupling cases.The study also analyzes the effects of borehole size,domain volume,and crack pressure update strategy on fracturing behavior.Furthermore,the performance of the improved algorithm in terms of crack propagation rate,micro-crack formation,and fluid pressure distribution was further evaluated.The results indicate that while large-size boreholes delay crack initiation,the cracks propagate more rapidly once formed.Additionally,the optimized domain volume calculation and crack pressure update strategy significantly shorten the pressure propagation stage,promote crack propagation,and improve computational efficiency. 展开更多
关键词 Hydraulic fracturing Fluid flow algorithm Domain volume optimization Crack pressure update Borehole size
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Research on Bed Call System Based on AT89C52
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作者 Hong Wang Lili Wu 《Journal of Electronic Research and Application》 2025年第1期254-262,共9页
How to realize intelligent and fast bed calls has been a key concern of hospitals.The traditional wired bed call system is not only costly but also less efficient.In this paper,research on bed call systems based on AT... How to realize intelligent and fast bed calls has been a key concern of hospitals.The traditional wired bed call system is not only costly but also less efficient.In this paper,research on bed call systems based on AT89C52 microcontroller is carried out.The nurse-side host(AT89C52)and the bedside slave(AT89C52)communicate over long distances using wireless communication technology.The system transmits signals,including Liquid Crystal Display(LCD),voice announcements,and beeping alarms,to indicate the bed number requiring assistance.This allows the nurse to respond promptly.The system supports real-time updates,where calls and processing occur independently,ensuring efficiency.It is not only cost-effective but also enables a rapid and intelligent call-and-response process. 展开更多
关键词 Bed call system AT89C52 Wireless communication technology Real-time update Call and processing
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Real-Time Identity Authentication Scheme Based on Dynamic Credentials for Power AIGC System
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作者 Feng Wei Zhao Chen +3 位作者 Yin Wang Dongqing Liu Xun Zhang Zhao Zhou 《Computers, Materials & Continua》 2025年第3期5325-5341,共17页
The integration of artificial intelligence(AI)with advanced power technologies is transforming energy system management,particularly through real-time data monitoring and intelligent decision-making driven by Artifici... The integration of artificial intelligence(AI)with advanced power technologies is transforming energy system management,particularly through real-time data monitoring and intelligent decision-making driven by Artificial Intelligence Generated Content(AIGC).However,the openness of power system channels and the resource-constrained nature of power sensors have led to new challenges for the secure transmission of power data and decision instructions.Although traditional public key cryptographic primitives can offer high security,the substantial key management and computational overhead associated with these primitives make them unsuitable for power systems.To ensure the real-time and security of power data and command transmission,we propose a lightweight identity authentication scheme tailored for power AIGC systems.The scheme utilizes lightweight symmetric encryption algorithms,minimizing the resource overhead on power sensors.Additionally,it incorporates a dynamic credential update mechanism,which can realize the rotation and update of temporary credentials to ensure anonymity and security.We rigorously validate the security of the scheme using the Real-or-Random(ROR)model and AVISPA simulation,and the results show that our scheme can resist various active and passive attacks.Finally,performance comparisons and NS3 simulation results demonstrate that our proposed scheme offers enhanced security features with lower overhead,making it more suitable for power AIGC systems compared to existing solutions. 展开更多
关键词 Cyber security identity authentication dynamic credential update AIGC
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Chinese Society of Clinical Oncology Non-small Cell Lung Cancer(CSCO NSCLC)guidelines in 2024:key update on the management of early and locally advanced NSCLC
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作者 Siyuan Chen Zhijie Wang Boyang Sun 《Cancer Biology & Medicine》 2025年第3期191-196,共6页
The Chinese Society of Clinical Oncology Non-small Cell Lung Cancer(CSCO NSCLC)guidelines were first published in 2016,ranking among the earliest-released guidelines within the CSCO series.In 2020 the CSCO published s... The Chinese Society of Clinical Oncology Non-small Cell Lung Cancer(CSCO NSCLC)guidelines were first published in 2016,ranking among the earliest-released guidelines within the CSCO series.In 2020 the CSCO published separate guidelines for NSCLC and small cell lung cancer(SCLC)for the first time to improve clinical usability. 展开更多
关键词 improve clinical usability Clinical Usability Chinese Society Clinical Oncology Non Small Cell Lung Cancer update CSCO NSCLC Guidelines Early NSCLC Locally Advanced NSCLC
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Efficient One-Way Time Synchronization for VANET withMLE-Based Multi-Stage Update
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作者 Hyeontae Joo Sangmin Lee +1 位作者 Kiseok Kim Hwangnam Kim 《Computers, Materials & Continua》 2025年第8期2789-2804,共16页
As vehicular networks become increasingly pervasive,enhancing connectivity and reliability has emerged as a critical objective.Among the enabling technologies for advanced wireless communication,particularly those tar... As vehicular networks become increasingly pervasive,enhancing connectivity and reliability has emerged as a critical objective.Among the enabling technologies for advanced wireless communication,particularly those targeting low latency and high reliability,time synchronization is critical,especially in vehicular networks.However,due to the inherent mobility of vehicular environments,consistently exchanging synchronization packets with a fixed base station or access point is challenging.This issue is further exacerbated in signal shadowed areas such as urban canyons,tunnels,or large-scale indoor hallswhere other technologies,such as global navigation satellite system(GNSS),are unavailable.One-way synchronization techniques offer a feasible approach under such transient connectivity conditions.One-way schemes still suffer from long convergence times to reach the required synchronization accuracy in these circumstances.In this paper,we propose a WLAN-based multi-stage clock synchronization scheme(WMC)tailored for vehicular networks.The proposed method comprises an initial hard update stage to rapidly achieve synchronization,followed by a high-precision stable stage based on Maximum Likelihood Estimation(MLE).By implementing the scheme directly at the network driver,we address key limitations of hard update mechanisms.Our approach significantly reduces the initial period to collect high-quality samples and offset estimation time to reach sub-50μs accuracy,and subsequently transitions to a refined MLE-based synchronization stage,achieving stable accuracy at approximately 30μs.The windowed moving average stabilized(reaching 90%of the baseline)in approximately 35 s,which corresponds to just 5.1%of the baseline time accuracy.Finally,the impact of synchronization performance on the localization model was validated using the Simulation of Urban Mobility(SUMO).The results demonstrate that more accurate conditions for position estimation can be supported,with an improvement about 38.5%in the mean error. 展开更多
关键词 One-way time synchronization maximum likelihood estimation hybrid clock update
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Updates of CSCO guidelines for colorectal cancer version 2025
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作者 Demin Lu Caixia Dong +4 位作者 Kailai Wang Chenyang Ye Liubo Chen Ying Yuan Hanguang Hu 《Chinese Journal of Cancer Research》 2025年第3期297-302,共6页
Colorectal cancer(CRC)is the most frequently diagnosed malignancy of the digestive system and the second leading cause of cancer-related deaths worldwide(1).In China,CRC ranks as the second most common cancer with inc... Colorectal cancer(CRC)is the most frequently diagnosed malignancy of the digestive system and the second leading cause of cancer-related deaths worldwide(1).In China,CRC ranks as the second most common cancer with incidence and mortality rates continuing to rise(2).The Chinese Society of Clinical Oncology(CSCO)first introduced its guidelines in 2017,and since then,they have been updated annually to incorporate the latest clinical research findings,drug availability,and expert consensus(3-8).This article presents the key updates in the 2025 edition compared to the 2024 version. 展开更多
关键词 digestive system colorectal cancer VERSION clinical research findings updateS CSCO guidelines edition colorectal cancer crc
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A Dynamic Knowledge Base Updating Mechanism-Based Retrieval-Augmented Generation Framework for Intelligent Question-and-Answer Systems
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作者 Yu Li 《Journal of Computer and Communications》 2025年第1期41-58,共18页
In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilizati... In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilization of this information. This study proposes a novel framework for intelligent Question-and-Answer (Q&A) systems based on Retrieval-Augmented Generation (RAG) to address these issues. The system efficiently acquires domain-specific knowledge by leveraging external databases, including Relational Databases (RDBs) and graph databases, without additional fine-tuning for Large Language Models (LLMs). Crucially, the framework integrates a Dynamic Knowledge Base Updating Mechanism (DKBUM) and a Weighted Context-Aware Similarity (WCAS) method to enhance retrieval accuracy and mitigate inherent limitations of LLMs, such as hallucinations and lack of specialization. Additionally, the proposed DKBUM dynamically adjusts knowledge weights within the database, ensuring that the most recent and relevant information is utilized, while WCAS refines the alignment between queries and knowledge items by enhanced context understanding. Experimental validation demonstrates that the system can generate timely, accurate, and context-sensitive responses, making it a robust solution for managing complex business logic in specialized industries. 展开更多
关键词 Retrieval-Augmented Generation Question-and-Answer Large Language Models Dynamic Knowledge Base Updating Mechanism Weighted Context-Aware Similarity
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Gain adaptive tuning method for fiber Raman amplifier based on two-stage neural networks and double weights updates
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作者 MU Kuanlin WU Yue 《Optoelectronics Letters》 2025年第5期284-289,共6页
We present a gain adaptive tuning method for fiber Raman amplifier(FRA) using two-stage neural networks(NNs) and double weights updates. After training the connection weights of two-stage NNs separately in training ph... We present a gain adaptive tuning method for fiber Raman amplifier(FRA) using two-stage neural networks(NNs) and double weights updates. After training the connection weights of two-stage NNs separately in training phase, the connection weights of the unified NN are updated again in verification phase according to error between the predicted and target gains to eliminate the inherent error of the NNs. The simulation results show that the mean of root mean square error(RMSE) and maximum error of gains are 0.131 d B and 0.281 d B, respectively. It shows that the method can realize adaptive adjustment function of FRA gain with high accuracy. 展开更多
关键词 gain adaptive tuning connection weights error predicted target gains training connection weights unified nn gain adaptive tuning method double weights updates fiber raman amplifier fra
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架设局域网内的Update服务器
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作者 贾大江 宋晓涛 《山西电力》 2004年第4期64-65,共2页
越来越多的病毒利用微软操作系统的漏洞传播,及时给系统升级打补丁成了计算机管理的一项重要工作。在局域网内架设软件升级服务器,可以提高升级系统的效率。为计算机系统的安全运行提供保障。
关键词 局域网 update服务器 网络管理员 工作组
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BGP协议中UPDATE报文的并行化处理方法 被引量:2
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作者 丁利娜 王兴伟 +1 位作者 李福亮 黄敏 《小型微型计算机系统》 CSCD 北大核心 2016年第11期2459-2463,共5页
互联网的规模日益扩大,作为域间路由协议标准的BGP协议,其性能面临着前所未有的考验.而路由更新(UPDATE)报文仍采用串行化的方式来处理,处理速度慢,极大地影响了BGP协议的性能.为此,提出一种UPDATE报文的并行化处理方法来解决这个问题.... 互联网的规模日益扩大,作为域间路由协议标准的BGP协议,其性能面临着前所未有的考验.而路由更新(UPDATE)报文仍采用串行化的方式来处理,处理速度慢,极大地影响了BGP协议的性能.为此,提出一种UPDATE报文的并行化处理方法来解决这个问题.该方法采用流水线技术和多线程技术,能够提高UPDATE报文的处理速度.为了进一步提高该方法的效率,我们在UPDATE报文的并行化处理过程中引入了垃圾回收机制和多线程动态调节策略.最后,我们在Quagga原型系统上对该并行化处理方法进行了仿真实现,并与Quagga中原始的BGPD模块的测试结果进行了对比分析,实验结果表明,本文设计的UPDATE报文的并行化处理方法是可行且有效的. 展开更多
关键词 BGP协议 update报文 并行化处理 流水线 多线程
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ORACLE游标中的多表UPDATE行锁讨论 被引量:3
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作者 张练兴 马明磊 《江西师范大学学报(自然科学版)》 CAS 北大核心 2005年第6期489-491,共3页
介绍了Oracle中的封锁机制,分析了共享更新封锁的特点,并就游标中的多表更新行锁以及怎样避免死锁错误进行了讨论.
关键词 ORACLE数据库 游标 多表update行锁
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如何在内联网上架设Windows Update服务器
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作者 石磊 《中国金融电脑》 2004年第7期57-58,共2页
关键词 内联网 互联网 物理隔离 WINDOWS update 服务器
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Realization of remote update technology for embedded equipment based on μC/OS-Ⅱ 被引量:2
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作者 孟辉 潘炼 《Journal of Measurement Science and Instrumentation》 CAS 2014年第3期69-72,共4页
Aiming at the inaccessible problem of remote embedded devices update and maintenance, this paper presents a method using general packet radio service (GPRS) to achieve update based on the embedded real-time operatin... Aiming at the inaccessible problem of remote embedded devices update and maintenance, this paper presents a method using general packet radio service (GPRS) to achieve update based on the embedded real-time operating system (RTOS) μC/OS-Ⅱ. It introduces architecture of the system first. And then it uses LPC1768 chip as the central processing unit, SIM900A module for data transmission, and SST25VF016B to store the data. To ensure accuracy of the data transmis- sion, cyclic redundancy code (CRC) is adopted. The software uses fixed bootstrap and mutable update program, and thus the embedded devices can still normally start in case of update failure. Finally, high stability and extensive adaptability of the system are verified by experimental data. 展开更多
关键词 μC/OS-ⅡμC/OS-ⅡμC/OS-Ⅱ remote update general packet radio service (GPRS) embedded system
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Update on hepatocellular carcinoma: Pathologists' review 被引量:32
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作者 Tony El Jabbour Stephen M Lagana Hwajeong Lee 《World Journal of Gastroenterology》 SCIE CAS 2019年第14期1653-1665,共13页
Histopathologic diversity and several distinct histologic subtypes of hepatocellular carcinoma(HCC) are well-recognized. Recent advances in molecular pathology and growing knowledge about the biology associated with d... Histopathologic diversity and several distinct histologic subtypes of hepatocellular carcinoma(HCC) are well-recognized. Recent advances in molecular pathology and growing knowledge about the biology associated with distinct histologic features and immuno-profile in HCC allowed pathologists to update classifications. Improving sub-classification will allow for more clinically relevant diagnoses and may allow for stratification into biologically meaningful subgroups. Therefore, immuno-histochemical and molecular testing are not only diagnostically useful, but also are being incorporated as crucial components in predicting prognosis of the patients with HCC. Possibilities of targeted therapy are being explored in HCC, and it will be important for pathologists to provide any data that may be valuable from a theranostic perspective. Herein, we review and provide updates regarding the pathologic sub-classification of HCC.Pathologic diagnostic approach and the role of biomarkers as prognosticators are reviewed. Further, the histopathology of four particular subtypes of HCC:Steatohepatitic, clear cell, fibrolamellar and scirrhous-and their clinical relevance, and the recent consensus on combined HCC-cholangiocarcinoma is summarized. Finally, emerging novel biomarkers and new approaches to HCC stratification are reviewed. 展开更多
关键词 HEPATOCELLULAR CARCINOMA SUBTYPE Classification REVIEW update
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GPS/BDS/INS tightly coupled integration accuracy improvement using an improved adaptive interacting multiple model with classified measurement update 被引量:19
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作者 Houzeng HAN Jian WANG Mingyi DU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第3期556-566,共11页
An Extended Kalman Filter(EKF) is commonly used to fuse raw Global Navigation Satellite System(GNSS) measurements and Inertial Navigation System(INS) derived measurements. However, the Conventional EKF(CEKF) s... An Extended Kalman Filter(EKF) is commonly used to fuse raw Global Navigation Satellite System(GNSS) measurements and Inertial Navigation System(INS) derived measurements. However, the Conventional EKF(CEKF) suffers the problem for which the uncertainty of the statistical properties to dynamic and measurement models will degrade the performance.In this research, an Adaptive Interacting Multiple Model(AIMM) filter is developed to enhance performance. The soft-switching property of Interacting Multiple Model(IMM) algorithm allows the adaptation between two levels of process noise, namely lower and upper bounds of the process noise. In particular, the Sage adaptive filtering is applied to adapt the measurement covariance on line. In addition, a classified measurement update strategy is utilized, which updates the pseudorange and Doppler observations sequentially. A field experiment was conducted to validate the proposed algorithm, the pseudorange and Doppler observations from Global Positioning System(GPS) and Bei Dou Navigation Satellite System(BDS) were post-processed in differential mode.The results indicate that decimeter-level positioning accuracy is achievable with AIMM for GPS/INS and GPS/BDS/INS configurations, and the position accuracy is improved by 35.8%, 34.3% and 33.9% for north, east and height components, respectively, compared to the CEKF counterpartfor GPS/BDS/INS. Degraded performance for BDS/INS is obtained due to the lower precision of BDS pseudorange observations. 展开更多
关键词 Adaptive filtering BeiDou navigation satellite system (BDS) Classified measurement update Global positioning system (GPS) Inertial navigation system (INS) Interacting multiple model Tightly coupled
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