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Dose Distribution Verifications of IMRT for NPC 被引量:1
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作者 李勤 李良 +1 位作者 韩军 梁志文 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第5期673-676,共4页
In order to explore a dose distribution verification procedure of intensity modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC) and establish its evaluation criteria, we performed 35 two-dimensio... In order to explore a dose distribution verification procedure of intensity modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC) and establish its evaluation criteria, we performed 35 two-dimensional (2D) patient-specific IMRT verifications over the year i006. The percent of pixels passing 7 and the normalized agreement test (NAT) index were mainly used to represent the agreement between the measured and computed dose distributions with three criteria (2%/2 mm, 3%/3 mm and 5%/3 mm) as recommended in the literature. The results were that all cases passed through verifications with three criteria except that the NAT index of one case was beyond the limitation, and the three tolerance levels of 2%/2mm, 3%/3 mm and 5%/3 mm produced similar clinical verification results but led to different percent of pixels passing Y and NAT index. Our data showed that the percent of pixels passing y and the NAT index were complementary to evaluate future IMRT verifications as two significant metrics. Due to the influence of the noise and the trait of the software, we considered an IMRT plan as acceptable in case of the percent ofpixels passing y 〉95% and the NAT index 〈5 with the 5%/3 mm criteria for IMRT patient-specific quality assurance (QA). 展开更多
关键词 dose distribution dose verification intensity modulated radiation therapy
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Application of Statistical Process Control for Setting Action Thresholds as Quality Assurance of Dose Verifications in External Beam Radiotherapy
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作者 Philip Kioko Ndonye Samuel Nii Adu Tagoe 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2022年第1期22-35,共14页
Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) ... Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) treatment of cervical cancer. Materials and Methods: A study of QA verification of target doses of 198 cervical cancer patients undergoing External Beam Radiotherapy (EBRT) treatments at two different cancer treatment centers in Kenya was conducted. The target doses were determined from measured entrance doses by the diode in vivo dosimetry. Process Behavior Charts (PBC) developed by SPC were applied for setting Action Thresholds (AT) on the target doses. The AT set was then proposed as QA limits for acceptance or rejection of verified target doses overtime of the EBRT process. Result and Discussion: Target doses for the 198 patients were calculated and SPC applied to test whether the action limits set by the Process Behavior Charts could be applied as QA for verified doses in EBRT. Results for the two sub-groups of n = 3 and n = 4 that were tested produced action thresholds which are within clinical dose specifications for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. Conclusion: Action thresholds set by SPC were within the clinical dose specification of ±5% uncertainty for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. So the concept of SPC could be applied in setting QA action limits for dose verifications in EBRT. 展开更多
关键词 Quality Assurance Statistical Process Control Action Thresholds Dose Verification External Beam Radiation Therapy
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Numerical simulations and experimental verifications at micro-,meso-,andmacroscales of droplet evaporation:A comprehensive review with special focus on saline droplets
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作者 Youchen Ning Yunhua Gan +1 位作者 Chuanshuai Dong Ronghui Qi 《Droplet》 2025年第1期1-19,共19页
Evaporation of saline droplets significantly impacts industrial processes such as water and gas treatment.Simulations,with advantages in describing temperature,concentration,and velocity distribution inside the drople... Evaporation of saline droplets significantly impacts industrial processes such as water and gas treatment.Simulations,with advantages in describing temperature,concentration,and velocity distribution inside the droplet,receive increasing attentions.This paper summarized research on numerical simulations of droplet evaporation atmicro-,meso-,and macroscales,emphasizing saline or multicomponent droplets.Accurate description of physics at phase interfaces andwithin proves to be critical for modeling.While recent studies have investigated on interface motion and temperature distribution,the coupling effect of internal concentration and flow distribution is still rarely considered.Among numerical methods,the lattice Boltzmann method is suitable for droplet scale due to its ability to handle non-continuum behavior.Bridging multiscale models remains a challenge,particularly in describing Marangoni and capillary flows.Experimental approaches to the effects of external physical fields(electric,magnetic,convection,and laser)and substrate properties on evaporation were also reviewed.Visualizing evaporation under various conditions can validate macroscopic models,while experiments with different substrates can validate molecular scale simulations,as substrate properties primarily affect evaporation by affecting capillary flow at the droplet bottom.This paper comprehensively reviewed numerical research on droplet evaporation,and analyzed the advantages,limitations,and development directions of various numericalmethods. 展开更多
关键词 numerical simulations MICROSCALE industrial processes MESOSCALE multicomponent dropletsaccurate description physics water gas treatmentsimulationswith experimental verifications droplet evaporation
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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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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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HashTrie Functional Framework and Its Application in Chinese-English Pattern Matching
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作者 ZUO Zhengkang ZHOU Chao +1 位作者 ZENG Zhicheng WANG Changjing 《Wuhan University Journal of Natural Sciences》 2025年第2期184-194,共11页
Most existing multi-pattern matching algorithms are designed for single English texts leading to issues such as missed matches and space expansion when applied to Chinese-English mixed-text environments.The Hash Trie-... Most existing multi-pattern matching algorithms are designed for single English texts leading to issues such as missed matches and space expansion when applied to Chinese-English mixed-text environments.The Hash Trie-based matching machine demonstrates strong compatibility with both Chinese and English,ensuring high accuracy in text processing and subtree positioning.In this study,a novel functional framework based on the HashTrie structure is proposed and mechanically verified using Isabelle/HOL.This framework is applied to design Functional Multi-Pattern Matching(FMPM),the first functional multi-pattern matching algorithm for Chinese-English mixed texts.FMPM constructs the HashTrie matching machine using character codes and threads the machine according to the associations between pattern strings.The experimental results show that as the stored string information increases,the proposed algorithm demonstrates more significant optimization in retrieval efficiency.FMPM simplifies the implementation of the Threaded Hash Trie(THT)for Chinese-English mixed texts,effectively reducing the uncertainties in the transition from the algorithm description to code implementation.FMPM addresses the problem of space explosion Chinese-English mixed texts and avoids issues such as bound variable iteration errors.The functional framework of the HashTrie structure serves as a reference for the formal verification of future HashTrie-based algorithms. 展开更多
关键词 multi-pattern matching Chinese-English mixed HashTrie FUNCTIONAL mechanized verification
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Enhanced Kinship Verification through Ear Images:A Comparative Study of CNNs,Attention Mechanisms,and MLP Mixer Models
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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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Semantic Knowledge Based Reinforcement Learning Formalism for Smart Learning Environments
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作者 Taimoor Hassan Ibrar Hussain +3 位作者 Hafiz Mahfooz Ul Haque Hamid Turab Mirza Muhammad Nadeem Ali Byung-Seo Kim 《Computers, Materials & Continua》 2025年第10期2071-2094,共24页
Smart learning environments have been considered as vital sources and essential needs in modern digital education systems.With the rapid proliferation of smart and assistive technologies,smart learning processes have ... Smart learning environments have been considered as vital sources and essential needs in modern digital education systems.With the rapid proliferation of smart and assistive technologies,smart learning processes have become quite convenient,comfortable,and financially affordable.This shift has led to the emergence of pervasive computing environments,where user’s intelligent behavior is supported by smart gadgets;however,it is becoming more challenging due to inconsistent behavior of Artificial intelligence(AI)assistive technologies in terms of networking issues,slow user responses to technologies and limited computational resources.This paper presents a context-aware predictive reasoning based formalism for smart learning environments that facilitates students in managing their academic as well as extra-curricular activities autonomously with limited human intervention.This system consists of a three-tier architecture including the acquisition of the contextualized information from the environment autonomously,modeling the system using Web Ontology Rule Language(OWL 2 RL)and Semantic Web Rule Language(SWRL),and perform reasoning to infer the desired goals whenever and wherever needed.For contextual reasoning,we develop a non-monotonic reasoning based formalism to reason with contextual information using rule-based reasoning.The focus is on distributed problem solving,where context-aware agents exchange information using rule-based reasoning and specify constraints to accomplish desired goals.To formally model-check and simulate the system behavior,we model the case study of a smart learning environment in the UPPAAL model checker and verify the desired properties in the model,such as safety,liveness and robust properties to reflect the overall correctness behavior of the system with achieving the minimum analysis time of 0.002 s and 34,712 KB memory utilization. 展开更多
关键词 CONTEXT-AWARENESS reinforcement learning multi-agent systems non-monotonic reasoning formal 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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The miR164a targets CsNAC1 to negatively regulate the cold tolerance of tea plants(Camellia sinensis)
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作者 Siya Li Lu Cao +3 位作者 Ziwen Zhou Yaohua Cheng Xianchen Zhang Yeyun Li 《Journal of Integrative Agriculture》 2025年第8期3073-3086,共14页
Cold stress widely impairs the quality and yield of tea plants. The miR164 family and its target NAC transcription factor have been identified as crucial regulators in response to cold stress. However, the role of miR... Cold stress widely impairs the quality and yield of tea plants. The miR164 family and its target NAC transcription factor have been identified as crucial regulators in response to cold stress. However, the role of miR164 and CsNAC in cold tolerance in tea plants was little understood. In our study, the expression level of CsMIR164a was significantly reduced under cold stress and significantly and negatively correlated with that of CsNAC1.5' RACE and GUS histochemical assays showed that CsNAC1 was cleaved by CsMIR164a. The CsMIR164a-silenced tea leaves promoted the expression levels of CsNAC1 and CsCBFs and exhibited greater cold tolerance. Also, the overexpression of CsNAC1 enhanced cold tolerance in transgenic Arabidopsis plants by promoting the expression levels of AtCBFs. In contrast, the heterologous overexpression of CsMIR164a in Arabidopsis decreased the expression level of AtNACs and AtCBFs and thus impaired cold tolerance. Additionally, silencing of CsNAC1 impaired the expression levels of CsCBFs, resulting in greater cold sensitivity in tea leaves. Our present study demonstrated that the miR164a-CsNAC1 module may play a negative role in the cold tolerance of tea plants via the CsCBF-dependent pathway. 展开更多
关键词 tea plants cold stress MIRNAS NAC transcription factor functional verification
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Application of Seismic Frequency Resonance Technology for Karst Detection at Qingshuitang Wollastonite Mining Area of Hezhou,South China
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作者 Xiaoli Gou Shehong Li +8 位作者 He Yu Xuhong Zhou Hui Zhou Guang He Shangsong Han Chunmei Li Wenjiang Luo Zhiying Mu Mingyu Lu 《Journal of Environmental & Earth Sciences》 2025年第6期426-438,共13页
Karst caves are among the most common and critical geological hazards in karst regions.Due to their marked differences in physical properties compared to the surrounding rock,they can be detected using various geophys... Karst caves are among the most common and critical geological hazards in karst regions.Due to their marked differences in physical properties compared to the surrounding rock,they can be detected using various geophysical techniques.Karsts have developed on the surface of the Qingshuitang Wollastonite Mining Area in Huangtian Town,Hezhou City,Guangxi Province.In line with mine safety production requirements,a professional assessment of the potential development of karst caves must be conducted within 150 m of the mining area’s surface.Following an on-site investiga-tion and comparison with traditional geophysical methods,seismic frequency resonance technology(Seismic FRT)was selected for detection due to its convenience,flexibility,cost-effectiveness,and rapid data acquisition capabilities.Contour maps of the apparent wave impedance and geological profiles along the survey lines were obtained through data collection and processing.In combination with surface karst and mining geology,32 karst caves(hidden danger points)and 15 karst development zones were identified.Drilling verification was conducted at the A428 and B122 anomalous points on the A1# and B1# survey lines.The verification results were consistent with the inferred depths and maximum apparent wave impedance anomalies,confirming that Seismic FRT is a feasible and effective method for detecting hid-den karst development areas in mines. 展开更多
关键词 KARST Seismic Frequency Resonance Technology Abnormal Wave Impedance Drilling Verification Hezhou
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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 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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Contextual design and real-time verification for agile casting design
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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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Preserving the Peaceful Use of Celestial Bodies:Prohibitions and Permissions
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作者 Moamen Mohamed Sayed Mrisho Mlinga Idrisa LI Shouping 《Aerospace China》 2025年第2期39-46,共8页
The Outer Space Treaty(OST)remains a cornerstone of international space law,enshrining the principle of peaceful use for celestial bodies.However,ambiguities in its provisions,particularly regarding military activitie... The Outer Space Treaty(OST)remains a cornerstone of international space law,enshrining the principle of peaceful use for celestial bodies.However,ambiguities in its provisions,particularly regarding military activities and dual-use technologies,pose significant challenges in the 21st century.This paper examines the treaty’s limitations in addressing modern space militarization,commercial-military convergence,and resource exploitation.It critiques the lack of robust verification mechanisms and proposes clarifications to ensure sustainable and cooperative space exploration.The analysis highlights the urgent need for updated legal frameworks to govern private actors and emerging technologies while preserving the OST’s foundational principles.The paper evaluates recent policy initiatives to enhance space weapons regulations,including the Russo-Chinese treaty proposal to ban space-based weapons and the EU’s International Code of Conduct for Space.It concludes existing provisions indicate a reluctance to limit nuclear weapons in space,but are a milestone in regulating the arms race’s expansion.However,ambiguities persist regarding prohibited activities. 展开更多
关键词 Outer Space Treaty peaceful use space militarization dual-use technologies verification mechanisms
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Speeches at the sub-forum on metrology technology
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《China Standardization》 2025年第6期51-59,共9页
At present,AI is reshaping the global industrial landscape at an unprecedented depth.As the cornerstone suppor ting technological innovation and industrial development,metrology is radiating new vitality in the AI era... At present,AI is reshaping the global industrial landscape at an unprecedented depth.As the cornerstone suppor ting technological innovation and industrial development,metrology is radiating new vitality in the AI era.It is not only a verification scale for algorithm accuracy and a trust anchor for sensing systems,but also a strategic link for China and ASEAN to deepen industrial collaboration.Metrology runs through the entire innovation chain of AI,providing verifiable and reproducible scientific basis for technological innovation and industrial development. 展开更多
关键词 verification scale technological innovation industrial developmentmetrology trust anchor algorithm accuracy METROLOGY deepen industrial collaborationmetrology sensing systemsbut
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Unveiling Xuanshen decoction:A novel approach to combat slow transit constipation
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作者 Xing-Lin Zeng Lian-Jun Zhu +2 位作者 Yu Zhang Xiang-Dong Yang Yu-Jun Zhu 《World Journal of Gastroenterology》 2025年第30期126-143,共18页
BACKGROUND Xuanshen decoction(XSD)is a traditional Chinese medicine formulation that is often applied in treating slow transit constipation(STC).However,its specific therapeutic mechanism remains to be characterized.A... BACKGROUND Xuanshen decoction(XSD)is a traditional Chinese medicine formulation that is often applied in treating slow transit constipation(STC).However,its specific therapeutic mechanism remains to be characterized.AIM To investigate the mechanism of XSD for STC,we combined network pharmacology prediction,molecular docking analysis,and in vivo studies.METHODS The therapeutic effects of XSD on loperamide-induced STC in rats were assessed through 24-hour fecal number,fecal moisture content,and intestinal propelling rate.Hematoxylin–eosin and Alcian blue/periodic acid-Schiff staining were applied to analyze colonic mucosa for histopathological presentation and mucin production.Next,the mechanism of action of XSD for STC was elucidated through network pharmacology and molecular docking analyses,and the findings were validated by the animal experiments.RESULTS XSD significantly alleviated the symptoms of STC in rats.Relative to the STC rats,in the medium-dose XSD and high-dose XSD rats,stem cell factor,C-kit,phosphophosphoinositide 3-kinase/phosphoinositide 3-kinase,phospho-protein kinase B/protein kinase B,catalase,and superoxide dismutase were substantially upregulated(P<0.01);nuclear factor erythroid 2-related factor 2(nuclear/cytoplasmic)and B-cell lymphoma 2(Bcl-2)were increased(P<0.05),while cleaved caspase-3,Bcl-2-associated X protein(Bax)/Bcl-2,and malondialdehyde were significantly reduced(P<0.01).Heme oxygenase-1 and glutathione peroxidase in the high-dose XSD group were significantly increased(P<0.01),and Bax was statistically lowered(P<0.01);glutathione peroxidase in the medium-dose XSD group was increased(P<0.05),while Bax was reduced(P<0.05).CONCLUSION XSD may inhibit oxidative-stress-induced apoptosis in interstitial cells of Cajal by stimulating the phosphoinositide 3-kinase/protein kinase B/nuclear factor erythroid 2-related factor 2 pathway,thereby effectively treating STC. 展开更多
关键词 Slow transit constipation Oxidative stress Network pharmacology Experimental verification Molecular docking
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Low-frequency signal generation in space based on high-frequency electric-antenna array and Doppler effect
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作者 CUI Anjing LI Daojing +6 位作者 WU Jiang GAO Jinghan ZHOU Kai HU Chufeng WU Shumei SHI Danni LI Guang 《Journal of Systems Engineering and Electronics》 2025年第1期24-36,共13页
Low-frequency signals have been proven valuable in the fields of target detection and geological exploration.Nevertheless,the practical implementation of these signals is hindered by large antenna diameters,limiting t... Low-frequency signals have been proven valuable in the fields of target detection and geological exploration.Nevertheless,the practical implementation of these signals is hindered by large antenna diameters,limiting their potential applications.Therefore,it is imperative to study the creation of lowfrequency signals using antennas with suitable dimensions.In contrast to conventional mechanical antenna techniques,our study generates low-frequency signals in the spatial domain utilizing the principle of the Doppler effect.We also defines the antenna array architecture,the timing sequency,and the radiating element signal waveform,and provides experimental prototypes including 8/64 antennas based on earlier research.In the conducted experiments,121 MHz,40 MHz,and 10 kHz composite signals are generated by 156 MHz radiating element signals.The composite signal spectrum matches the simulations,proving our low-frequency signal generating method works.This holds significant implications for research on generating low-frequency signals with small-sized antennas. 展开更多
关键词 frequency conversion array signal processing experimental verification Doppler effect
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