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NetVerifier:Scalable Verification for Programmable Networks
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作者 Ying Yao Le Tian +1 位作者 Yuxiang Hu Pengshuai Cui 《Computers, Materials & Continua》 2026年第5期1830-1848,共19页
In the process of programmable networks simplifying network management and increasing network flexibility through custom packet behavior,security incidents caused by human logic errors are seriously threatening their ... In the process of programmable networks simplifying network management and increasing network flexibility through custom packet behavior,security incidents caused by human logic errors are seriously threatening their safe operation,robust verificationmethods are required to ensure their correctness.As one of the formalmethods,symbolic execution offers a viable approach for verifying programmable networks by systematically exploring all possible paths within a program.However,its application in this field encounters scalability issues due to path explosion and complex constraint-solving.Therefore,in this paper,we propose NetVerifier,a scalable verification system for programmable networks.Tomitigate the path explosion issue,we developmultiple pruning strategies that strategically eliminate irrelevant execution paths while preserving verification integrity by precisely identifying the execution paths related to the verification purpose.To address the complex constraint-solving problem,we introduce an execution results reuse solution to avoid redundant computation of the same constraints.To apply these solutions intelligently,a matching algorithm is implemented to automatically select appropriate solutions based on the characteristics of the verification requirement.Moreover,Language Aided Verification(LAV),an assertion language,is designed to express verification intentions in a concise form.Experimental results on diverse open-source programs of varying scales demonstrate NetVerifier’s improvement in scalability and effectiveness in identifying potential network errors.In the best scenario,compared with ASSERT-P4,NetVerifier reduced the execution path,verification time,and memory occupation of the verification process by 99.92%,94.76%,and 65.19%,respectively. 展开更多
关键词 Programmable network network verification symbolic execution SCALABILITY
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Establishment and verification of anthropogenic speciated VOCs emission inventory of Central China 被引量:3
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作者 Xuan Lu Dong Zhang +9 位作者 Lanxin Wang Shefang Wang Xinran Zhang Yali Liu Keying Chen Xinshuai Song Shasha Yin Ruiqin Zhang Shanshan Wang Minghao Yuan 《Journal of Environmental Sciences》 2025年第3期406-418,共13页
Improving the accuracy of anthropogenic volatile organic compounds(VOCs)emission inventory is crucial for reducing atmospheric pollution and formulating control policy of air pollution.In this study,an anthropogenic s... Improving the accuracy of anthropogenic volatile organic compounds(VOCs)emission inventory is crucial for reducing atmospheric pollution and formulating control policy of air pollution.In this study,an anthropogenic speciated VOCs emission inventory was established for Central China represented by Henan Province at a 3 km×3 km spatial resolution based on the emission factormethod.The 2019 VOCs emission in Henan Provincewas 1003.5 Gg,while industrial process source(33.7%)was the highest emission source,Zhengzhou(17.9%)was the city with highest emission and April and August were the months with the more emissions.High VOCs emission regions were concentrated in downtown areas and industrial parks.Alkanes and aromatic hydrocarbons were the main VOCs contribution groups.The species composition,source contribution and spatial distribution were verified and evaluated through tracer ratio method(TR),Positive Matrix Factorization Model(PMF)and remote sensing inversion(RSI).Results show that both the emission results by emission inventory(EI)(15.7 Gg)and by TRmethod(13.6 Gg)and source contribution by EI and PMF are familiar.The spatial distribution of HCHO primary emission based on RSI is basically consistent with that of HCHO emission based on EI with a R-value of 0.73.The verification results show that the VOCs emission inventory and speciated emission inventory established in this study are relatively reliable. 展开更多
关键词 VOCs verification Species composition Tracer ratio PMF Remote sensing inversion
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Enhanced Kinship Verification through Ear Images:A Comparative Study of CNNs,Attention Mechanisms,and MLP Mixer Models 被引量:1
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作者 Thien-Tan Cao Huu-Thanh Duong +3 位作者 Viet-Tuan Le Hau Nguyen Trung Vinh Truong Hoang Kiet Tran-Trung 《Computers, Materials & Continua》 2025年第6期4373-4391,共19页
Kinship verification is a key biometric recognition task that determines biological relationships based on physical features.Traditional methods predominantly use facial recognition,leveraging established techniques a... Kinship verification is a key biometric recognition task that determines biological relationships based on physical features.Traditional methods predominantly use facial recognition,leveraging established techniques and extensive datasets.However,recent research has highlighted ear recognition as a promising alternative,offering advantages in robustness against variations in facial expressions,aging,and occlusions.Despite its potential,a significant challenge in ear-based kinship verification is the lack of large-scale datasets necessary for training deep learning models effectively.To address this challenge,we introduce the EarKinshipVN dataset,a novel and extensive collection of ear images designed specifically for kinship verification.This dataset consists of 4876 high-resolution color images from 157 multiracial families across different regions,forming 73,220 kinship pairs.EarKinshipVN,a diverse and large-scale dataset,advances kinship verification research using ear features.Furthermore,we propose the Mixer Attention Inception(MAI)model,an improved architecture that enhances feature extraction and classification accuracy.The MAI model fuses Inceptionv4 and MLP Mixer,integrating four attention mechanisms to enhance spatial and channel-wise feature representation.Experimental results demonstrate that MAI significantly outperforms traditional backbone architectures.It achieves an accuracy of 98.71%,surpassing Vision Transformer models while reducing computational complexity by up to 95%in parameter usage.These findings suggest that ear-based kinship verification,combined with an optimized deep learning model and a comprehensive dataset,holds significant promise for biometric applications. 展开更多
关键词 Biometric analytics ear kin Inceptionv4 kinship verification KIN ear images
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Contextual design and real-time verification for agile casting design 被引量:1
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作者 Dong Xiang Chu-hao Zhou +3 位作者 Xuan-pu Dong Shu-ren Guo Yan-song Ding Hua-tang Cao 《China Foundry》 2025年第2期231-238,共8页
In the foundry industries,process design has traditionally relied on manuals and complex theoretical calculations.With the advent of 3D design in casting,computer-aided design(CAD)has been applied to integrate the fea... In the foundry industries,process design has traditionally relied on manuals and complex theoretical calculations.With the advent of 3D design in casting,computer-aided design(CAD)has been applied to integrate the features of casting process,thereby expanding the scope of design options.These technologies use parametric model design techniques for rapid component creation and use databases to access standard process parameters and design specifications.However,3D models are currently still created through inputting or calling parameters,which requires numerous verifications through calculations to ensure the design rationality.This process may be significantly slowed down due to repetitive modifications and extended design time.As a result,there are increasingly urgent demands for a real-time verification mechanism to address this issue.Therefore,this study proposed a novel closed-loop model and software development method that integrated contextual design with real-time verification,dynamically verifying relevant rules for designing 3D casting components.Additionally,the study analyzed three typical closed-loop scenarios of agile design in an independent developed intelligent casting process system.It is believed that foundry industries can potentially benefit from favorably reduced design cycles to yield an enhanced competitive product market. 展开更多
关键词 agile design context-design casting process design real-time verification smart manufacturing
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Research on multi-scale simulation and dynamic verification of high dynamic MEMS components in additive manufacturing 被引量:1
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作者 Sining Lv Hengzhen Feng +2 位作者 Wenzhong Lou Chuan Xiao Shiyi Li 《Defence Technology(防务技术)》 2025年第5期275-291,共17页
Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects s... Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects such as porosity issues, significant deformation, surface cracks, and challenging control of surface morphology encountered during the selective laser melting(SLM) additive manufacturing(AM) process of specialized Micro Electromechanical System(MEMS) components, multiparameter optimization and micro powder melt pool/macro-scale mechanical properties control simulation of specialized components are conducted. The optimal parameters obtained through highprecision preparation and machining of components and static/high dynamic verification are: laser power of 110 W, laser speed of 600 mm/s, laser diameter of 75 μm, and scanning spacing of 50 μm. The density of the subordinate components under this reference can reach 99.15%, the surface hardness can reach 51.9 HRA, the yield strength can reach 550 MPa, the maximum machining error of the components is 4.73%, and the average surface roughness is 0.45 μm. Through dynamic hammering and high dynamic firing verification, SLM components meet the requirements for overload resistance. The results have proven that MEM technology can provide a new means for the processing of MEMS components applied in high dynamic environments. The parameters obtained in the conclusion can provide a design basis for the additive preparation of MEMS components. 展开更多
关键词 Additive manufacturing High dynamic MEMS components Multiscale control Process optimization High dynamic verification
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C-BIVM:A Cognitive-Based Integrity Verification Model for IoT-Driven Smart Cities
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作者 Radhika Kumari Kiranbir Kaur +4 位作者 Ahmad Almogren Ayman Altameem Salil Bharany Yazeed Yasin Ghadi Ateeq Ur Rehman 《Computers, Materials & Continua》 2025年第9期5509-5525,共17页
The exponential growth of the Internet of Things(IoT)has revolutionized various domains such as healthcare,smart cities,and agriculture,generating vast volumes of data that require secure processing and storage in clo... The exponential growth of the Internet of Things(IoT)has revolutionized various domains such as healthcare,smart cities,and agriculture,generating vast volumes of data that require secure processing and storage in cloud environments.However,reliance on cloud infrastructure raises critical security challenges,particularly regarding data integrity.While existing cryptographic methods provide robust integrity verification,they impose significant computational and energy overheads on resource-constrained IoT devices,limiting their applicability in large-scale,real-time scenarios.To address these challenges,we propose the Cognitive-Based Integrity Verification Model(C-BIVM),which leverages Belief-Desire-Intention(BDI)cognitive intelligence and algebraic signatures to enable lightweight,efficient,and scalable data integrity verification.The model incorporates batch auditing,reducing resource consumption in large-scale IoT environments by approximately 35%,while achieving an accuracy of over 99.2%in detecting data corruption.C-BIVM dynamically adapts integrity checks based on real-time conditions,optimizing resource utilization by minimizing redundant operations by more than 30%.Furthermore,blind verification techniques safeguard sensitive IoT data,ensuring privacy compliance by preventing unauthorized access during integrity checks.Extensive experimental evaluations demonstrate that C-BIVM reduces computation time for integrity checks by up to 40%compared to traditional bilinear pairing-based methods,making it particularly suitable for IoT-driven applications in smart cities,healthcare,and beyond.These results underscore the effectiveness of C-BIVM in delivering a secure,scalable,and resource-efficient solution tailored to the evolving needs of IoT ecosystems. 展开更多
关键词 Internet of Things(IoT) smart cities data integrity verification BDI cognitive intelligence algebraic signatures batch auditing resource-constrained devices blind verification
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In vivo 3D dose distribution verification for lung cancer:from rigid-body model to porcine lung
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作者 Yutao Zhang Kai Xie +9 位作者 Lintao Song Jiewei Lai Haiping Zheng Qianjia Huang Hao Wang Tao Lin Liugang Gao Jiawei Sun Jianrong Dai Xinye Ni 《Bio-Design and Manufacturing》 2025年第6期994-1008,I0032,共16页
This study introduces a novel concept,biological in vivo three-dimensional(3D)dose distribution verification,aimed at investigating how respiratory motion affects the efficacy of lung cancer radiotherapy,representing ... This study introduces a novel concept,biological in vivo three-dimensional(3D)dose distribution verification,aimed at investigating how respiratory motion affects the efficacy of lung cancer radiotherapy,representing an evolution from the current standard of rigid-body dose distribution verification.A 3D ex vivo biological lung motion simulation device(3D-BioLungEx)was designed to replicate human respiration.A radiotherapy plan of the patient was copied to the porcine lung,which was driven by 3D-BioLungEx to simulate various respiratory patterns that occur during treatment.To ensure anatomical consistency with the patient’s lung structure,during transmission,skin,skeleton,and organs were adjusted according to CT images of the porcine lung.The patient’s radiotherapy plan was then adapted to the porcine lung using the Monaco treatment planning system(TPS).Next,an iterative optimization and scatter inversion-based dose distribution retro-analysis algorithm(IOSI-BLDose)was developed to calculate the dose distribution during treatment.Gamma passing rates were used to quantify discrepancies between this dose distribution and that of the radiotherapy plan.When respiratory conditions were replicated,the passing rate reached up to 93.61%,while irregular breathing dropped it to 70%-90%,primarily due to amplitude changes.However,cycle variations had minimal impact.Compared to conventional rigid-body dose distribution verification,our method provides real-time biological feedback and more effectively captures motion-induced deviations.Accordingly,our biological in vivo 3D dose distribution verification has potential for improving treatment precision and enabling adaptive radiotherapy in clinical practice. 展开更多
关键词 Biological lung 3D printing Motion simulation device RADIOTHERAPY Lung cancer Dose distribution verification
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Design and Ground Verification for Vision-Based Relative Navigation Systems of Microsatellites
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作者 DU Ronghua LIAO Wenhe ZHANG Xiang 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第1期37-55,共19页
This paper presents the design and ground verification for vision-based relative navigation systems of microsatellites,which offers a comprehensive hardware design solution and a robust experimental verification metho... This paper presents the design and ground verification for vision-based relative navigation systems of microsatellites,which offers a comprehensive hardware design solution and a robust experimental verification methodology for practical implementation of vision-based navigation technology on the microsatellite platform.Firstly,a low power consumption,light weight,and high performance vision-based relative navigation optical sensor is designed.Subsequently,a set of ground verification system is designed for the hardware-in-the-loop testing of the vision-based relative navigation systems.Finally,the designed vision-based relative navigation optical sensor and the proposed angles-only navigation algorithms are tested on the ground verification system.The results verify that the optical simulator after geometrical calibration can meet the requirements of the hardware-in-the-loop testing of vision-based relative navigation systems.Based on experimental results,the relative position accuracy of the angles-only navigation filter at terminal time is increased by 25.5%,and the relative speed accuracy is increased by 31.3% compared with those of optical simulator before geometrical calibration. 展开更多
关键词 microsatellites vision-based relative navigation optical simulator ground verification angles-only navigation
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Toward next-generation networks:A blockchain-based approach for core network architecture and roaming identity verification
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作者 Yi Gong Boyuan Yu +4 位作者 Lei Yang Fanke Meng Lei Liu Xinjue Hu Zhan Xu 《Digital Communications and Networks》 2025年第2期326-336,共11页
With the evolution of next-generation communication networks,ensuring robust Core Network(CN)architecture and data security has become paramount.This paper addresses critical vulnerabilities in the architecture of CN ... With the evolution of next-generation communication networks,ensuring robust Core Network(CN)architecture and data security has become paramount.This paper addresses critical vulnerabilities in the architecture of CN and data security by proposing a novel framework based on blockchain technology that is specifically designed for communication networks.Traditional centralized network architectures are vulnerable to Distributed Denial of Service(DDoS)attacks,particularly in roaming scenarios where there is also a risk of private data leakage,which imposes significant operational demands.To address these issues,we introduce the Blockchain-Enhanced Core Network Architecture(BECNA)and the Secure Decentralized Identity Authentication Scheme(SDIDAS).The BECNA utilizes blockchain technology to decentralize data storage,enhancing network security,stability,and reliability by mitigating Single Points of Failure(SPoF).The SDIDAS utilizes Decentralized Identity(DID)technology to secure user identity data and streamline authentication in roaming scenarios,significantly reducing the risk of data breaches during cross-network transmissions.Our framework employs Ethereum,free5GC,Wireshark,and UERANSIM tools to create a robust,tamper-evident system model.A comprehensive security analysis confirms substantial improvements in user privacy and network security.Simulation results indicate that our approach enhances communication CNs security and reliability,while also ensuring data security. 展开更多
关键词 Blockchain Core network Privacy data protection Decentralized identity Roaming identity verification
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Verification and validation of a numerical wave tank with momentum source wave generation
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作者 Housheng Zhang Yijing Hu +1 位作者 Biao Huang Xin Zhao 《Acta Mechanica Sinica》 2025年第3期23-38,共16页
systematic verification and validation(V&V)of our previously proposed momentum source wave generation method is performed.Some settings of previous numerical wave tanks(NWTs)of regular and irregular waves have bee... systematic verification and validation(V&V)of our previously proposed momentum source wave generation method is performed.Some settings of previous numerical wave tanks(NWTs)of regular and irregular waves have been optimized.The H2-5 V&V method involving five mesh sizes with mesh refinement ratio being 1.225 is used to verify the NWT of regular waves,in which the wave height and mass conservation are mainly considered based on a Lv3(H s=0.75 m)and a Lv6(H s=5 m)regular wave.Additionally,eight different sea states are chosen to validate the wave height,mass conservation and wave frequency of regular waves.Regarding the NWT of irregular waves,five different sea states with significant wave heights ranging from 0.09 m to 12.5 m are selected to validate the statistical characteristics of irregular waves,including the profile of the wave spectrum,peak frequency and significant wave height.Results show that the verification errors for Lv3 and Lv6 regular wave on the most refined grid are−0.018 and−0.35 for wave height,respectively,and−0.14 and for−0.17 mass conservation,respectively.The uncertainty estimation analysis shows that the numerical error could be partially balanced out by the modelling error to achieve a smaller validation error by adjusting the mesh size elaborately.And the validation errors of the wave height,mass conservation and dominant frequency of regular waves under different sea states are no more than 7%,8% and 2%,respectively.For a Lv3(H_(s)=0.75 m)and a Lv6(H_(s)=5 m)regular wave,simulations are validated on the wave height in wave development section for safety factors FS≈1 and FS≈0.5-1,respectively.Regarding irregular waves,the validation errors of the significant wave height and peak frequency are both lower than 2%. 展开更多
关键词 verification and validation Wave generation Momentum source function Regular wave Irregular wave Uncertainty estimation
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Verification and Validation for Large Eddy Simulation of Cavitating Flow Around a Projectile Near the Free Surface
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作者 Linfeng Deng Yun Long +1 位作者 Huaiyu Cheng Bin Ji 《哈尔滨工程大学学报(英文版)》 2025年第4期659-681,共23页
Verification and validation(V&V)is a helpful tool for evaluating simulation errors,but its application in unsteady cavitating flow remains a challenging issue due to the difficulty in meeting the requirement of an... Verification and validation(V&V)is a helpful tool for evaluating simulation errors,but its application in unsteady cavitating flow remains a challenging issue due to the difficulty in meeting the requirement of an asymptotic range.Hence,a new V&V approach for large eddy simulation(LES)is proposed.This approach offers a viable solution for the error estimation of simulation data that are unable to satisfy the asymptotic range.The simulation errors of cavitating flow around a projectile near the free surface are assessed using the new V&V method.The evident error values are primarily dispersed around the cavity region and free surface.The increasingly intense cavitating flow increases the error magnitudes.In addition,the modeling error magnitudes of the Dynamic Smagorinsky-Lilly model are substantially smaller than that of the Smagorinsky-Lilly model.The present V&V method can capture the decrease in the modeling errors due to model enhancements,further exhibiting its applicability in cavitating flow simulations.Moreover,the monitoring points where the simulation data are beyond the asymptotic range are primarily dispersed near the cavity region,and the number of such points grows as the cavitating flow intensifies.The simulation outcomes also suggest that the re-entrant jet and shedding cavity collapse are the chief sources of vorticity motions,which remarkably affect the simulation accuracy.The results of this study provide a valuable reference for V&V research. 展开更多
关键词 Cavitating flow Free surface verification and validation Error analyses Asymptotic range
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Program Derivation and Mechanized Verification of Edit Distance Algorithm
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作者 YOU Zhen ZHANG Chen +1 位作者 SUN Huan ZUO Zhengkang 《Wuhan University Journal of Natural Sciences》 2025年第6期576-588,共13页
Edit distance is an algorithm to measure the difference between two strings,usually represented as the minimum number of editing operations required to transform one string into another.The edit distance algorithm inv... Edit distance is an algorithm to measure the difference between two strings,usually represented as the minimum number of editing operations required to transform one string into another.The edit distance algorithm involves complex dependencies and constraints,making state management and verification work tedious.This paper proposes a derivation and verification method that avoids directly handling dependencies and constraints by proving the equivalence between the edit distance algorithm and existing functional modeling.First,the derivation process of edit distance algorithm mainly includes 1)describing problem specifications,2)inductively deducing recursive relations,3)formally constructing loop invariants using the optimization theory(memorization technology and optimal decision table)and properties(optimal substructure property and subproblems overlapping property)of the edit distance algorithm,4)generating the Minimalistic Imperative Programming Language(IMP)code based on the recursive relations.Second,the problem specification,loop invariants,and generated IMP code are input into Verification Condition Generator(VCG),which automatically generate five verification conditions,and then the correctness of edit distance algorithm is verified in the Isabelle/HOL theorem prover.The method utilizes formal technologies and theorem prover to complete the derivation and verification of the edit distance algorithm,and it can be applied to linear and nonlinear dynamic programming problems. 展开更多
关键词 Isabelle/HOL mechanized verification edit distance verification Condition Generator(VCG)
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Research on Variable Condition Properties and Experimental Verification of a Variable Cross-Section Scroll Expander
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作者 Junying Wei Guangxian Yin +5 位作者 Jihao Zhang Wenwen Chang Chenrui Zhang Zhengyi Li Long Chang Minghan Peng 《Frontiers in Heat and Mass Transfer》 2025年第4期1185-1201,共17页
The scroll expander,as the core component of the micro-compressed air energy storage and power generation system,directly affects the output efficiency of the system.Meanwhile,the scroll profile plays a central role i... The scroll expander,as the core component of the micro-compressed air energy storage and power generation system,directly affects the output efficiency of the system.Meanwhile,the scroll profile plays a central role in determining the output performance of the scroll expander.In this study,in order to investigate the output characteristics of a variable cross-section scroll expander,numerical simulation and experimental studies were con-ducted by using Computational Fluid Dynamics(CFD)methods and dynamic mesh techniques.The impact of critical parameters on the output performance of the scroll expander was analyzed through the utilization of the control variable method.It is found that increasing the inlet pressure and temperature within a certain range can improve the output power of the scroll expander.However,the increase in temperature and meshing clearance leads to a decline in the overall output performance of the scroll expander,leading to a decrease in volumetric efficiency by 8.43%and 12.79%,respectively.The experiments demonstrate that under equal inlet pressure conditions,increasing the inlet temperature elevates both the rotational speed and torque output of the scroll expander.Specifically,compared to operating at normal temperatures,the output torque increases by 21.8%under high-temperature conditions.However,the rate of speed and torque variation decreases as a consequence of enlarged meshing clearance,resulting in increased internal leakage and reduction in isentropic efficiency. 展开更多
关键词 Circular involute variable cross-section scroll expander numerical simulation internal flow field output characteristics experimental verification
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Study on the Construction and Verification of CDIO Teaching Model Based on AI Virtual Scene Data Feedback
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作者 Yanyan Wang Wenyan Qu Yuman Yuan 《Journal of Contemporary Educational Research》 2025年第10期164-173,共10页
Combining the characteristics of the course“Comprehensive Training of E-Commerce Live Streaming,”this paper embeds the CDIO(Conceive-Design-Implement-Operate)method into the live streaming training process,carries o... Combining the characteristics of the course“Comprehensive Training of E-Commerce Live Streaming,”this paper embeds the CDIO(Conceive-Design-Implement-Operate)method into the live streaming training process,carries out the virtual scene“e-commerce live streaming”course design and project-based teaching reform that integrates teaching training with learning effects,and establishes a set of cross-professional student live streaming training procedures guided by the CDIO engineering method.The training results show that the CDIO practical teaching model supported by data feedback plays an important role and significance in improving students’learning effects,and also provides some new experiences for integrating engineering thinking into the construction of new liberal arts. 展开更多
关键词 CDIO Teaching model Construction and verification
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移动机器人路径规划算法综述 被引量:1
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作者 张永宏 郭子健 +2 位作者 陆竹恒 蒋亮 曹海啸 《计算机工程与应用》 北大核心 2026年第2期26-39,共14页
路径规划算法是实现移动机器人自主导航的关键技术之一,其性能决定了路径规划的质量。为全面地了解移动机器人路径规划算法的研究现状和发展,对常用算法进行系统综述。针对路径规划算法的特点,将其划分为传统算法、基于采样的算法、基... 路径规划算法是实现移动机器人自主导航的关键技术之一,其性能决定了路径规划的质量。为全面地了解移动机器人路径规划算法的研究现状和发展,对常用算法进行系统综述。针对路径规划算法的特点,将其划分为传统算法、基于采样的算法、基于人工智能的算法和基于智能仿生的算法;基于上述分类,简要介绍了算法原理和实际应用场景,重点阐述近年来各种算法的相关研究成果,概括对比各类算法的优缺点;选取了四种算法在同一仿真环境下验证算法的有效性。最后,对移动机器人未来发展趋势进行展望,以期为移动机器人路径规划研究提供参考。 展开更多
关键词 移动机器人 路径规划 算法分类与融合 算法验证
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两种化学发光法检测血清铁蛋白的性能差异及一致性分析
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作者 林夏雯 李爱梅 +2 位作者 冯雪凤 陶志嵩 胡玲莉 《医学研究与战创伤救治》 北大核心 2026年第2期168-173,共6页
目的通过两种不同的化学发光检测技术(电化学发光和直接化学发光),在四种检测平台上对铁蛋白的检测性能进行评估,同时对收集的临床剩余血清样本进行结果的一致性评价。方法应用罗氏Cobas e801(电化学发光法)、西门子Atellica IM(直接化... 目的通过两种不同的化学发光检测技术(电化学发光和直接化学发光),在四种检测平台上对铁蛋白的检测性能进行评估,同时对收集的临床剩余血清样本进行结果的一致性评价。方法应用罗氏Cobas e801(电化学发光法)、西门子Atellica IM(直接化学发光法)、国产普门e CL9000(电化学发光法)、国产新产业MAGLUMI X8(直接化学发光法)四种检测平台及其配套试剂分别进行精密度、正确度、线性区间、稀释倍数和参考区间的性能验证,并对收集的94例临床剩余血清标本分别在四个检测平台检测后的数据进行一致性分析。结果四种检测平台铁蛋白试剂的精密度、正确度均通过验证,四种检测平台在各自的线性区间内线性良好。稀释倍数验证各系统在1∶2、1∶5、1∶10均表现出较好的回收率。四种检测平台的铁蛋白参考区间均通过验证。将收集的血清样本用四种检测平台的检测结果进行一致性分析,以罗氏e801为参比系统,普门与罗氏的一致性相关系数为0.985,一致性极好。西门子、新产业与罗氏的一致性相关系数分别为0.900、0.955,一致性好。Bland-Altman评估显示,与罗氏系统相比,普门与罗氏的一致性最好,西门子、普门、新产业与罗氏相比均呈现正相对偏差,其中西门子的正偏差最显著。结论四种检测平台的铁蛋白性能参数精密度、正确度、线性区间、稀释倍数和参考区间均符合临床检测需求。国产电化学发光普门与进口电化学发光罗氏的一致性优于西门子与新产业;且单个试剂成本相对进口品牌较低,国产电化学发光普门在各个医学决定水平的偏倚均满足要求。 展开更多
关键词 铁蛋白 性能验证 化学发光法 精密度 正确度 一致性评价
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基于增材制造的碳化硅双面反射镜设计与可靠性验证
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作者 王成彬 孙胜利 +2 位作者 孙小进 马孝浩 胡凯 《光学精密工程》 北大核心 2026年第1期26-34,共9页
为实现同轴四反光学系统中主镜和四镜所构成的Φ516 mm双面共体反射镜轻量化、高刚度的设计目标,提出一种在传统轻量化设计基础上,融合多参数优化与碳化硅增材制造技术的方法。基于工程经验建立反射镜初始模型,选择主要结构尺寸建立多... 为实现同轴四反光学系统中主镜和四镜所构成的Φ516 mm双面共体反射镜轻量化、高刚度的设计目标,提出一种在传统轻量化设计基础上,融合多参数优化与碳化硅增材制造技术的方法。基于工程经验建立反射镜初始模型,选择主要结构尺寸建立多参数优化模型,并基于多目标遗传算法进行结构参数优化,优化后的反射镜质量为6.8 kg,相对初始方案降低32.6%。最后,完成碳化硅双面反射镜3D打印及结构模态测试,所得一阶频率为1964 Hz。对两个镜面光学加工后,开展了重力影响试验、真空高低温试验和振动试验。结果表明,试验前后反射镜面形精度最大变化为0.001λ(λ=632 nm)。碳化硅双面反射镜结构设计和增材制造工艺具有良好的可靠性和稳定性。 展开更多
关键词 增材制造 碳化硅 双面反射镜 轻量化 可靠性验证
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日照时数传感器自动化核查装置的研究与应用
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作者 王敏 张世国 +4 位作者 方海涛 王凯 王毛翠 汪玮 章超 《计量学报》 北大核心 2026年第1期49-56,共8页
日照时数是地面气象观测要素之一。2018年起,我国2435个国家地面气象观测站已全部由人工观测仪器升级为光电式数字日照计实现自动观测。为满足省级气象部门日照时数计量需求,研制了日照时数传感器自动化核查装置。该装置以2台宽光谱太... 日照时数是地面气象观测要素之一。2018年起,我国2435个国家地面气象观测站已全部由人工观测仪器升级为光电式数字日照计实现自动观测。为满足省级气象部门日照时数计量需求,研制了日照时数传感器自动化核查装置。该装置以2台宽光谱太阳辐射计为计量标准器,具备自动指北定位、自动水平调节、自动数据采集处理等功能,可实现日照计室外核查。实验结果表明:标准器直接辐照度测量误差在±10%内,2台标准器一致性介于±5%间;被测日照计日照时数测量误差符合中国气象局技术规范要求(±1 h/d或±10%/d,取较大者),扩展不确定度U=0.45 h(k=2)。此外,晴朗天气测量结果一致性好,标准偏差在0.09 h内;多云天气对检测影响大,测量误差可高于平均测量误差0.79 h。 展开更多
关键词 气象计量学 日照时数 光电式数字日照计 核查装置 示值误差
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医疗失效模式与效应分析在手术安全核查Time-out环节中的应用
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作者 陈红 张春瑾 +1 位作者 吴波 王禾 《护理学杂志》 北大核心 2026年第6期54-58,共5页
目的探讨医疗失效模式与效应分析在手术安全核查Time-out环节中的应用效果,为提升手术室护理质量提供参考。方法采用历史对照性研究,将2023年8-10月的11204例手术患者作为对照组,在Time-out环节中采用常规手术安全核查方式;2024年5-7月... 目的探讨医疗失效模式与效应分析在手术安全核查Time-out环节中的应用效果,为提升手术室护理质量提供参考。方法采用历史对照性研究,将2023年8-10月的11204例手术患者作为对照组,在Time-out环节中采用常规手术安全核查方式;2024年5-7月的11543例手术患者作为观察组,通过成立医疗失效模式与效应分析小组确定手术室Time-out核查环节中的失效模式,分析根本原因,拟定行动计划并组织实施。结果观察组Time-out规范执行率、手术及麻醉风险陈述确切率、安全核查单填写准确率、安全核查单归档率显著优于对照组(均P<0.05)。结论应用医疗失效模式与效应分析对手术安全核查Time-out环节进行规范管理,可以有效提升Time-out核查流程执行的规范性,保障手术患者安全。 展开更多
关键词 手术室 医疗失效模式与效应分析 手术安全核查 术前暂停核查 护理安全 护理管理
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桔梗中黄酮类糖基转移酶基因PgUGT72B21的克隆与功能验证
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作者 李涛 郝志鹏 +3 位作者 任星榕 赵钰萤 王彩霞 薛强 《中草药》 北大核心 2026年第1期270-281,共12页
目的以桔梗Platycodon grandiflorus中糖基转移酶为研究对象,进行糖基转移酶PgUGT72B21基因的生物信息学分析、基因克隆与重组质粒构建、蛋白表达与纯化、催化功能验证、酶学性质研究、底物宽泛性考察。方法基于桔梗转录组数据筛选得到... 目的以桔梗Platycodon grandiflorus中糖基转移酶为研究对象,进行糖基转移酶PgUGT72B21基因的生物信息学分析、基因克隆与重组质粒构建、蛋白表达与纯化、催化功能验证、酶学性质研究、底物宽泛性考察。方法基于桔梗转录组数据筛选得到桔梗中关键糖基转移酶PgUGT72B21,进行基因克隆;利用基因重组技术构建了原核表达载体pET-28a-PgUGT72B21,转化至大肠杆菌BL21(DE3)感受态;根据His标签蛋白纯化试剂盒说明进行蛋白纯化,应用SDS-PAGE凝胶电泳检测蛋白的表达情况;通过HPLC和LC-MS系统检测酶促反应产物。结果通过克隆得到的桔梗糖基转移酶基因PgUGT72B21开放阅读框(open reading frame,ORF)长度1407 bp,编码468个氨基酸残基,相对分子质量约为51000,C末端存在高度保守的植物次生产物糖基转移酶(plant secondary product glycosyltransferase,PSPG)基序。系统进化分析表明,该糖基转移酶属于UGT72家族。体外酶促结果显示,PgUGT72B21可催化槲皮素C3位羟基糖基化生成异槲皮苷。通过异源表达与纯化得到重组蛋白后对其酶学性质进行了分析,表明PgUGT72B21催化反应的最适pH为6.0,最适温度为60℃,反应2 h后的底物转化率达到最高。其催化槲皮素的酶动力学参数米氏常数(Km)为390.10μmol/L,转化数(kcat)为11.10/min。进一步的底物宽泛性研究显示PgUGT72B21不仅能够催化槲皮素等黄酮醇类化合物,还能够催化芹菜素等黄酮类化合物。结论发现的新糖基转移酶PgUGT72B21对于丰富糖基化工具酶库具有重要意义,且能为进一步解析桔梗中黄酮糖苷的糖基化过程奠定基础。 展开更多
关键词 桔梗 糖基转移酶 UDP-葡萄糖 槲皮素 功能验证 酶动力学
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