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ASME Code Case 3029高温许用压应力计算方法的介绍及工程应用
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作者 马忠明 《化工设备与管道》 北大核心 2026年第1期24-30,共7页
介绍了高温蠕变工况下运行的压力容器可能出现的失效模式,结合工程设计现状,指出了我国当前压力容器标准体系在确定高温蠕变工况许用压应力时存在的技术瓶颈,在此基础之上引出ASME Code Case 3029,对其适用范围、发展历程、产生背景及... 介绍了高温蠕变工况下运行的压力容器可能出现的失效模式,结合工程设计现状,指出了我国当前压力容器标准体系在确定高温蠕变工况许用压应力时存在的技术瓶颈,在此基础之上引出ASME Code Case 3029,对其适用范围、发展历程、产生背景及工程意义进行了简单的介绍,以某工程设计项目中的实际结构为例,介绍了该方法的使用过程及注意事项,并结合压力容器工程设计领域的实际需求,对我国标准体系下一步的制定或修订方向提出了展望。 展开更多
关键词 code Case 3029 蠕变屈曲 失稳 压力容器 许用应力
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ChatGPT+VS Code在高中地理地图开发中的应用——以“国内人口迁移”为例
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作者 王凌宇 白絮飞 《中国信息技术教育》 2026年第1期81-84,共4页
人工智能技术在中学地理教学中的应用是大势所趋。当前的研究主要聚焦于其作为学生的“助学者”和教师的“助教者”两大角色。然而,现有应用方式存在一定局限性:作为“助学者”,若学生使用不当可能引发依赖性,削弱其独立思考能力;作为... 人工智能技术在中学地理教学中的应用是大势所趋。当前的研究主要聚焦于其作为学生的“助学者”和教师的“助教者”两大角色。然而,现有应用方式存在一定局限性:作为“助学者”,若学生使用不当可能引发依赖性,削弱其独立思考能力;作为“助教者”,若教师生成教学设计的指令过于宽泛,结果易出现“张冠李戴”或“似是而非”等问题,需教师二次加工。相反,若教师能针对教学设计中的特定模块提供详细准确的指令,人工智能技术输出的结果将更具准确性和实用性,展现出更高研究价值。因此,本文从人工智能技术“助教者”身份出发,摒弃传统完整的教学过程设计,聚焦备课中的“地图开发”模块,采用由人工智能技术生成地图代码并通过第三方软件运行的方式,实现快速辅助教师生成所需地图的目标,提升备课效率与教学质量。 展开更多
关键词 ChatGPT VS code 人工智能技术 中学地理 地图开发
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Rateless Polar Codes with Unequal Error Protection Property
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作者 Cui Chen Xiang Wei +1 位作者 Ma Siwei Guo Qing 《China Communications》 2026年第1期10-23,共14页
Mobile communications are reaching out to every aspect of our daily life,necessitating highefficiency data transmission and support for diverse data types and communication scenarios.Polar codes have emerged as a prom... Mobile communications are reaching out to every aspect of our daily life,necessitating highefficiency data transmission and support for diverse data types and communication scenarios.Polar codes have emerged as a promising solution due to their outstanding error-correction performance and low complexity.Unequal error protection(UEP)involves nonuniform error safeguarding for distinct data segments,achieving a fine balance between error resilience and resource allocation,which ultimately enhancing system performance and efficiency.In this paper,we propose a novel class of UEP rateless polar codes.The codes are designed based on matrix extension of polar codes,and elegant mapping and duplication operations are designed to achieve UEP property while preserving the overall performance of conventional polar codes.Superior UEP performance is attained without significant modifications to conventional polar codes,making it straightforward for compatibility with existing polar codes.A theoretical analysis is conducted on the block error rate and throughput efficiency performance.To the best of our knowledge,this work provides the first theoretical performance analysis of UEP rateless polar codes.Simulation results show that the proposed codes significantly outperform existing polar coding schemes in both block error rate and throughput efficiency. 展开更多
关键词 matrix extension polar codes rateless coding unequal error protection
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Efficient Polar Codes with Low Complexity for Correcting Insertions/Deletions in DPPM
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作者 Li Leran Liu Yuan +2 位作者 Yuan Ye Xiahou Wenqian Chen Maonan 《China Communications》 2026年第1期24-33,共10页
Differential pulse-position modulation(DP PM)can achieve a good compromise between power and bandwidth requirements.However,the output sequence has undetectable insertions and deletions.This paper proposes a successiv... Differential pulse-position modulation(DP PM)can achieve a good compromise between power and bandwidth requirements.However,the output sequence has undetectable insertions and deletions.This paper proposes a successive cancellation(SC)decoding scheme based on the weighted levenshtein distance(WLD)of polar codes for correcting insertions/deletions in DPPM systems.In this method,the WLD is used to calculate the transfer probabilities recursively to obtain likelihood ratios,and the low-complexity SC decoding method is built according to the error characteristics to match the DPPM system.Additionally,the proposed SC decoding scheme is extended to list decoding,which can further improve error correction performance.Simulation results show that the proposed scheme can effectively correct insertions/deletions in the DPPM system,which enhances its reliability and performance. 展开更多
关键词 DPPM insertions/deletions polar codes SC decoding
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Integration of Large Language Models(LLMs)and Static Analysis for Improving the Efficacy of Security Vulnerability Detection in Source Code
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作者 JoséArmando Santas Ciavatta Juan Ramón Bermejo Higuera +3 位作者 Javier Bermejo Higuera Juan Antonio Sicilia Montalvo Tomás Sureda Riera Jesús Pérez Melero 《Computers, Materials & Continua》 2026年第3期351-390,共40页
As artificial Intelligence(AI)continues to expand exponentially,particularly with the emergence of generative pre-trained transformers(GPT)based on a transformer’s architecture,which has revolutionized data processin... As artificial Intelligence(AI)continues to expand exponentially,particularly with the emergence of generative pre-trained transformers(GPT)based on a transformer’s architecture,which has revolutionized data processing and enabled significant improvements in various applications.This document seeks to investigate the security vulnerabilities detection in the source code using a range of large language models(LLM).Our primary objective is to evaluate the effectiveness of Static Application Security Testing(SAST)by applying various techniques such as prompt persona,structure outputs and zero-shot.To the selection of the LLMs(CodeLlama 7B,DeepSeek coder 7B,Gemini 1.5 Flash,Gemini 2.0 Flash,Mistral 7b Instruct,Phi 38b Mini 128K instruct,Qwen 2.5 coder,StartCoder 27B)with comparison and combination with Find Security Bugs.The evaluation method will involve using a selected dataset containing vulnerabilities,and the results to provide insights for different scenarios according to the software criticality(Business critical,non-critical,minimum effort,best effort)In detail,the main objectives of this study are to investigate if large language models outperform or exceed the capabilities of traditional static analysis tools,if the combining LLMs with Static Application Security Testing(SAST)tools lead to an improvement and the possibility that local machine learning models on a normal computer produce reliable results.Summarizing the most important conclusions of the research,it can be said that while it is true that the results have improved depending on the size of the LLM for business-critical software,the best results have been obtained by SAST analysis.This differs in“NonCritical,”“Best Effort,”and“Minimum Effort”scenarios,where the combination of LLM(Gemini)+SAST has obtained better results. 展开更多
关键词 AI+SAST secure code LLM benchmarking LLM vulnerability detection
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Gradient-Guided Assembly Instruction Relocation for Adversarial Attacks Against Binary Code Similarity Detection
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作者 Ran Wei Hui Shu 《Computers, Materials & Continua》 2026年第1期1372-1394,共23页
Transformer-based models have significantly advanced binary code similarity detection(BCSD)by leveraging their semantic encoding capabilities for efficient function matching across diverse compilation settings.Althoug... Transformer-based models have significantly advanced binary code similarity detection(BCSD)by leveraging their semantic encoding capabilities for efficient function matching across diverse compilation settings.Although adversarial examples can strategically undermine the accuracy of BCSD models and protect critical code,existing techniques predominantly depend on inserting artificial instructions,which incur high computational costs and offer limited diversity of perturbations.To address these limitations,we propose AIMA,a novel gradient-guided assembly instruction relocation method.Our method decouples the detection model into tokenization,embedding,and encoding layers to enable efficient gradient computation.Since token IDs of instructions are discrete and nondifferentiable,we compute gradients in the continuous embedding space to evaluate the influence of each token.The most critical tokens are identified by calculating the L2 norm of their embedding gradients.We then establish a mapping between instructions and their corresponding tokens to aggregate token-level importance into instructionlevel significance.To maximize adversarial impact,a sliding window algorithm selects the most influential contiguous segments for relocation,ensuring optimal perturbation with minimal length.This approach efficiently locates critical code regions without expensive search operations.The selected segments are relocated outside their original function boundaries via a jump mechanism,which preserves runtime control flow and functionality while introducing“deletion”effects in the static instruction sequence.Extensive experiments show that AIMA reduces similarity scores by up to 35.8%in state-of-the-art BCSD models.When incorporated into training data,it also enhances model robustness,achieving a 5.9%improvement in AUROC. 展开更多
关键词 Assembly instruction relocation adversary attack binary code similarity detection
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Improving MCUCN code to simulate ultracold neutron storage and transportation in superfluid^(4)He
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作者 Xue-Fen Han Fei Shen +6 位作者 Bin Zhou Xiao-Xiao Cai Tian-Cheng Yi Zhi-Liang Hu Song-Lin Wang Tian-Jiao Liang Robert Golub 《Nuclear Science and Techniques》 2026年第3期235-246,共12页
The ultracold neutron(UCN)transport code,MCUCN,designed initially for simulating UCN transportation from a solid deuterium(SD_2)source and neutron electric dipole moment experiments,could not simulate UCN storage and ... The ultracold neutron(UCN)transport code,MCUCN,designed initially for simulating UCN transportation from a solid deuterium(SD_2)source and neutron electric dipole moment experiments,could not simulate UCN storage and transportation in a superfluid^(4)He(SFHe,He-Ⅱ)source accurately.This limitation arose from the absence of an^(4)He upscattering mechanism and the absorption of^(3)He.And the provided source energy distribution in MCUCN is different from that in SFHe source.This study introduced enhancements to MCUCN to address these constraints,explicitly incorporating the^(4)He upscattering effect,the absorption of^(3)He,the loss caused by impurities on converter wall,UCN source energy distribution in SFHe,and the transmission through negative optical potential.Additionally,a Python-based visualization code for intermediate states and results was developed.To validate these enhancements,we systematically compared the simulation results of the Lujan Center Mark3 UCN system by MCUCN and the improved MCUCN code(iMCUCN)with UCNtransport simulations.Additionally,we compared the results of the SUN1 system simulated by MCUCN and iMCUCN with measurement results.The study demonstrates that iMCUCN effectively simulates the storage and transportation of ultracold neutrons in He-Ⅱ. 展开更多
关键词 Ultracold neutron Storage TRANSPORTATION Improved MCUCN code Upscattering effect Absorption by^(3)He
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Integrating Attention Mechanism with Code Structural Affinity and Execution Context Correlation for Automated Bug Repair
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作者 Jinfeng Ji Geunseok Yang 《Computers, Materials & Continua》 2026年第3期1708-1725,共18页
Automated Program Repair(APR)techniques have shown significant potential in mitigating the cost and complexity associated with debugging by automatically generating corrective patches for software defects.Despite cons... Automated Program Repair(APR)techniques have shown significant potential in mitigating the cost and complexity associated with debugging by automatically generating corrective patches for software defects.Despite considerable progress in APR methodologies,existing approaches frequently lack contextual awareness of runtime behaviors and structural intricacies inherent in buggy source code.In this paper,we propose a novel APR approach that integrates attention mechanisms within an autoencoder-based framework,explicitly utilizing structural code affinity and execution context correlation derived from stack trace analysis.Our approach begins with an innovative preprocessing pipeline,where code segments and stack traces are transformed into tokenized representations.Subsequently,the BM25 ranking algorithm is employed to quantitatively measure structural code affinity and execution context correlation,identifying syntactically and semantically analogous buggy code snippets and relevant runtime error contexts from extensive repositories.These extracted features are then encoded via an attention-enhanced autoencoder model,specifically designed to capture significant patterns and correlations essential for effective patch generation.To assess the efficacy and generalizability of our proposed method,we conducted rigorous experimental comparisons against DeepFix,a state-of-the-art APR system,using a substantial dataset comprising 53,478 studentdeveloped C programs.Experimental outcomes indicate that our model achieves a notable bug repair success rate of approximately 62.36%,representing a statistically significant performance improvement of over 6%compared to the baseline.Furthermore,a thorough K-fold cross-validation reinforced the consistency,robustness,and reliability of our method across diverse subsets of the dataset.Our findings present the critical advantage of integrating attentionbased learning with code structural and execution context features in APR tasks,leading to improved accuracy and practical applicability.Future work aims to extend the model’s applicability across different programming languages,systematically optimize hyperparameters,and explore alternative feature representation methods to further enhance debugging efficiency and effectiveness. 展开更多
关键词 Automated bug repair autoencoder algorithm buggy code analysis stack trace similarity machine learning for debugging
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基于LS-DYNA的圆盘式花生切根装置设计与试验
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作者 何晓宁 李梦竹 +5 位作者 常学良 尚书旗 王东伟 王家胜 杨紫奥 王如正 《农业工程学报》 北大核心 2025年第21期32-42,共11页
针对现有花生收获机械在收获过程中无法有效切根除膜的问题,该研究设计了一种适配于一垄双行花生联合收获机的双圆盘切根装置。通过对装置关键部件的受力及作业原理分析,设计其关键结构参数,结合Hypermesh和Livermore Software DYNAmics... 针对现有花生收获机械在收获过程中无法有效切根除膜的问题,该研究设计了一种适配于一垄双行花生联合收获机的双圆盘切根装置。通过对装置关键部件的受力及作业原理分析,设计其关键结构参数,结合Hypermesh和Livermore Software DYNAmics(LS-DYNA)对其进行显式动力学分析,得到切根过程中的切割力、应力及切割能量变化情况等,对比分析锯齿+锯齿(2A型)、非锯齿+非锯齿(2B型)和锯齿+非锯齿(AB型)三种不同圆盘刀组合切割方式的切割效果,确定最优组合形式为AB型,探究各因素对最大切根力和切割能量之间的影响规律并确定最佳参数组合。结果表明,当圆盘刀转速为239 r/min,圆盘刀倾角为5°,喂入速度为901 mm/s时,双圆盘切根装置性能最优,最大切根力为14.4 N。对优化结果进行验证试验,切净率为96.9%,除膜率为98.3%,研究结果可为进一步提升花生全程机械化装备性能提供理论依据。 展开更多
关键词 花生 收获机 花生秧蔓 双圆盘刀 ls-dyna仿真
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基于ANSYS/LS-DYNA的露天宽台阶爆破参数模拟实验研究
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作者 毛金峰 耿新宇 +2 位作者 董法 常治国 春坚超 《煤炭技术》 2025年第10期21-26,共6页
针对露天矿山爆破效率提升需求,提出基于孔网参数优化的宽台阶爆破技术体系,通过数值模拟与工程验证相结合的方法,系统探究台阶爆破参数对岩体破碎效果的影响规律。采用ANSYS/LS-DYNA建立三孔三维动力学模型,对比分析不同孔距、排距和... 针对露天矿山爆破效率提升需求,提出基于孔网参数优化的宽台阶爆破技术体系,通过数值模拟与工程验证相结合的方法,系统探究台阶爆破参数对岩体破碎效果的影响规律。采用ANSYS/LS-DYNA建立三孔三维动力学模型,对比分析不同孔距、排距和超深条件下应力波传播特性及破碎区演化规律,结合某露天矿剥离台阶的工程实践,构建包含底盘抵抗线、装药结构和起爆时序的宽台阶爆破优化参数体系。现场应用表明,该技术使矿山的爆破次数降低40%,爆破效率提升20%~30%,运营成本降低14.4%,有效解决了传统爆破中单次爆破台阶过窄、不能适应设备大型化的趋势等问题,为露天矿山智能化爆破设计提供了理论支撑与实践范式。 展开更多
关键词 ANSYS/ls-dyna 数值模拟 矿山爆破 宽台阶爆破
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基于ANSYS/LS-DYNA的扩展程序在矿山爆破工程中的应用
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作者 费爱萍 栾丽华 《能源与节能》 2025年第10期325-327,共3页
随着矿山开采深度的增加、矿岩特性的变化,爆破设计参数的优化问题成为制约爆破质量提高的关键因素。针对矿山爆破孔距、排距、微差时间的优化问题,应用C#语言进行编程对ANSYS/LS-DYNA的爆破参数优化程序进行固化,将建模、参数设置、求... 随着矿山开采深度的增加、矿岩特性的变化,爆破设计参数的优化问题成为制约爆破质量提高的关键因素。针对矿山爆破孔距、排距、微差时间的优化问题,应用C#语言进行编程对ANSYS/LS-DYNA的爆破参数优化程序进行固化,将建模、参数设置、求解计算、修改和重置等功能一体化,实现爆破参数优化模拟计算准确性和高效性的提升。以双孔微差爆破露天矿岩实际工程应用为例,系统地说明基于ANSYS/LS-DYNA的数值模拟程序的扩展功能及良好结果,该程序的应用使同等工作条件下前期处理效率提高43%,人为操作出错率降低45%。 展开更多
关键词 ANSYS/ls-dyna扩展程序 模拟参数 微差爆破
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基于LS-DYNA的滑移门平顺性仿真与试验分析
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作者 刘召龙 尹辉俊 +2 位作者 马书坤 陆日进 陈涛 《机械设计》 北大核心 2025年第7期158-163,共6页
MPV滑移门在长期使用过程中,会出现开关门过程卡滞不顺畅、中滑轮臂异响等影响滑移门平顺性品质的问题。为了在前期开发阶段就可以提升滑移门开关门过程的平顺性,对滑移门的部分导轨、滑轮臂等关键零件进行改进。基于有限元软件HyperMes... MPV滑移门在长期使用过程中,会出现开关门过程卡滞不顺畅、中滑轮臂异响等影响滑移门平顺性品质的问题。为了在前期开发阶段就可以提升滑移门开关门过程的平顺性,对滑移门的部分导轨、滑轮臂等关键零件进行改进。基于有限元软件HyperMesh建立了滑移门有限元刚柔耦合模型,通过动力学软件LS-DYNA计算结果,对滑移门系统开、闭过程的动力学特性进行研究,分析滑移门的运动平顺性,并提出改进方案,最终通过滑移门台架试验验证改进方案的有效性。 展开更多
关键词 ls-dyna 滑移门平顺性 刚柔耦合 导轨
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基于LS-DYNA的火箭发动机喷管流场数值模拟与验证
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作者 王亿明 周柯江 +2 位作者 张东东 范书立 李京杰 《计算力学学报》 北大核心 2025年第2期285-291,共7页
为了探究火箭发动机喷管的流场特性以及速度变化趋势,采用了LS-DYNA软件中CE/SE求解器,验证了来自于NPARC验证与确认算例库中的超声速轴对称喷管(收缩-扩张型喷管)的相关参数。本文试验媒介为空气,在喷管马赫数为2.22完全膨胀的情况下,... 为了探究火箭发动机喷管的流场特性以及速度变化趋势,采用了LS-DYNA软件中CE/SE求解器,验证了来自于NPARC验证与确认算例库中的超声速轴对称喷管(收缩-扩张型喷管)的相关参数。本文试验媒介为空气,在喷管马赫数为2.22完全膨胀的情况下,对喷管中心线速度和中心线上各点处的截面速度进行了数值模拟,并将模拟结果与试验结果对比。结果表明,CE/SE方法能够较好地预测喷管内的流动分布和关键参数,其计算结果和速度变化趋势与试验数据高度吻合,且与实验数据相差10%以内,有效验证了该方法计算火箭发动机喷管流场的可行性,未来可以进一步深入探索和优化该方法。 展开更多
关键词 火箭发动机 喷管流场 数值模拟验证 ls-dyna软件 CE/SE方法
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Figma2Code:面向Figma设计稿的自动代码生成方法 被引量:1
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作者 朱琳 封颖超杰 +8 位作者 朱航 王斯加 朱闽峰 喻晨昊 张钰荟 许达兴 赵德明 冯玉君 陈为 《计算机辅助设计与图形学学报》 北大核心 2025年第2期321-329,共9页
设计类创作工具已被广泛用于提高用户界面的设计效率,然而,根据设计稿开发代码是一件耗时费力的工作.针对现有的设计稿自动转代码的方案面临的代码可用性和复现结果准确性等问题,基于Figma设计工具提出一种自动代码生成方法——Figma2Co... 设计类创作工具已被广泛用于提高用户界面的设计效率,然而,根据设计稿开发代码是一件耗时费力的工作.针对现有的设计稿自动转代码的方案面临的代码可用性和复现结果准确性等问题,基于Figma设计工具提出一种自动代码生成方法——Figma2Code.首先,通过节点和图层优化提高设计稿元数据质量;其次,采用元数据标注信息的语义理解和图像识别技术识别组件;然后构建一套通用型的中间态数据结构,表示优化后的元数据和识别后的组件属性,以支持多种代码语言的生成;最后,基于模板生成可用代码,并通过函数抽取和元素循环输出提高代码可用性.采用生成代码的复现样式准确度量化评估和基于专家经验的代码可用性定性评估,证明了所提方法的有效性. 展开更多
关键词 设计稿转代码 逆向工程 用户界面 深度学习
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Correction:Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space
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作者 Mudassir Khalil Muhammad Imran Sharif +3 位作者 Ahmed Naeem Muhammad Umar Chaudhry Hafiz Tayyab Rauf Adham E.Ragab 《Computers, Materials & Continua》 SCIE EI 2025年第1期1461-1461,共1页
In the article“Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space”by Mudassir Khalil,Muhammad Imran Sharif,Ahmed Naeem,Muhammad Umar Chaudhry,Hafiz Tayyab Rauf,Adham E.Ragab C... In the article“Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space”by Mudassir Khalil,Muhammad Imran Sharif,Ahmed Naeem,Muhammad Umar Chaudhry,Hafiz Tayyab Rauf,Adham E.Ragab Computers,Materials&Continua,2023,Vol.77,No.2,pp.2031–2047.DOI:10.32604/cmc.2023.043687,URL:https://www.techscience.com/cmc/v77n2/54831,there was an error regarding the affiliation for the author Hafiz Tayyab Rauf.Instead of“Centre for Smart Systems,AI and Cybersecurity,Staffordshire University,Stoke-on-Trent,ST42DE,UK”,the affiliation should be“Independent Researcher,Bradford,BD80HS,UK”. 展开更多
关键词 Deep code CIELAB
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基于LS-DYNA的SPH-FEM火箭橇垂直水戽斗流固耦合仿真研究
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作者 张宁 董龙雷 +2 位作者 吕水燕 刘洋 付良 《装备环境工程》 2025年第11期1-9,共9页
目的更准确地得出火箭橇垂直水戽斗在超音速条件下,对不同水层的完整刹车过程的力学响应特性。方法采用HyperMesh划分高质量的有限元网格,基于LS-DYNA,采用FEM模拟垂直水戽斗的有限元模型,采用无网格的SPH粒子模拟长柱形水域粒子在刹车... 目的更准确地得出火箭橇垂直水戽斗在超音速条件下,对不同水层的完整刹车过程的力学响应特性。方法采用HyperMesh划分高质量的有限元网格,基于LS-DYNA,采用FEM模拟垂直水戽斗的有限元模型,采用无网格的SPH粒子模拟长柱形水域粒子在刹车时的飞散过程,对火箭橇垂直水戽斗与水层之间的交互行为进行数值模拟仿真,得出垂直水戽斗在运动过程中的最大应力点,以及应力变化的全过程时域响应和不同工况下戽斗刹车力的理论-仿真误差特性,并结合火箭橇垂直水戽斗刹车试验数据结果,验证不同工况下戽斗刹车力的仿实误差特性的结果。结果通过数据分析可以发现,仿真结果的平均误差和最大误差分别为6%和10%。结论结合理论推导、模拟仿真与试验测试,验证了基于LS-DYNA的SPH-FEM流固耦合的数值模拟方法能有效预测火箭橇垂直水戽斗完整刹车过程中的力学响应。 展开更多
关键词 火箭橇 水戽斗 ls-dyna SPH-FEM方法 流固耦合 动态响应
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基于矩形波的凿岩机凿击效率分析及LS-DYNA有限元仿真
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作者 唐裔豪 侯文朝 于涛 《机械工程师》 2025年第10期58-61,共4页
在冲击凿岩中,不同的输入波形影响凿岩效率,一般的工程实际大多采用矩形波作为输入波。文中利用波动力学从理论上求出凿岩机凿击效率系统模型,得出冲击动载参数的相关表达式,使用MATLAB数学工具求解凿岩机冲锤输入到钎杆中的矩形波持续... 在冲击凿岩中,不同的输入波形影响凿岩效率,一般的工程实际大多采用矩形波作为输入波。文中利用波动力学从理论上求出凿岩机凿击效率系统模型,得出冲击动载参数的相关表达式,使用MATLAB数学工具求解凿岩机冲锤输入到钎杆中的矩形波持续时间和凿击效率的关系,并通过非线性动力学分析软件LS-DYNA对其本构模型进行仿真计算,验证该系统模型的正确性,为以后凿岩机凿击效率优化提供一种有效的分析方法。 展开更多
关键词 冲击凿岩 矩形波 凿岩效率 ls-dyna仿真
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基于LS-DYNA的船舶-浮箱碰撞动力特性研究
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作者 颜洪斌 崔峻 袁培银 《舰船科学技术》 北大核心 2025年第24期57-61,共5页
随着船舶种类、数量、吨位的不断增长,三峡库区船舶通航时撞击桥梁的风险日益增大。为避免船舶撞击桥梁事故的发生,安装浮体式防撞装置是目前应用最广泛的保护手段。本文基于显式非线性基本理论,应用LS-DYNA有限元分析软件,对船舶-桥墩... 随着船舶种类、数量、吨位的不断增长,三峡库区船舶通航时撞击桥梁的风险日益增大。为避免船舶撞击桥梁事故的发生,安装浮体式防撞装置是目前应用最广泛的保护手段。本文基于显式非线性基本理论,应用LS-DYNA有限元分析软件,对船舶-桥墩防撞浮箱的碰撞全过程进行仿真分析。结果表明,船舶与防撞浮箱碰撞后,撞击力表现出强非线性波动特征;船舶受到的最大作用力与撞击速度、船舶排水量呈正相关;船舶所受最大撞击力出现在碰撞的中后期,碰撞力始终在高位波动;桥墩所受最大撞击力出现在碰撞接触瞬间,当碰撞全过程结束后,迅速回落到较低水平波动;在相同载重量、相同撞击速度的工况下,防撞浮箱最大可降低桥墩所受76%的撞击力,表现出对浮箱的优良保护性能。研究结果可为船舶-浮箱防撞工程建设提供理论方法与经验。 展开更多
关键词 船桥碰撞 有限元仿真 ls-dyna 防撞浮箱
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Detection and Recognition of Spray Code Numbers on Can Surfaces Based on OCR
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作者 Hailong Wang Junchao Shi 《Computers, Materials & Continua》 SCIE EI 2025年第1期1109-1128,共20页
A two-stage algorithm based on deep learning for the detection and recognition of can bottom spray codes and numbers is proposed to address the problems of small character areas and fast production line speeds in can ... A two-stage algorithm based on deep learning for the detection and recognition of can bottom spray codes and numbers is proposed to address the problems of small character areas and fast production line speeds in can bottom spray code number recognition.In the coding number detection stage,Differentiable Binarization Network is used as the backbone network,combined with the Attention and Dilation Convolutions Path Aggregation Network feature fusion structure to enhance the model detection effect.In terms of text recognition,using the Scene Visual Text Recognition coding number recognition network for end-to-end training can alleviate the problem of coding recognition errors caused by image color distortion due to variations in lighting and background noise.In addition,model pruning and quantization are used to reduce the number ofmodel parameters to meet deployment requirements in resource-constrained environments.A comparative experiment was conducted using the dataset of tank bottom spray code numbers collected on-site,and a transfer experiment was conducted using the dataset of packaging box production date.The experimental results show that the algorithm proposed in this study can effectively locate the coding of cans at different positions on the roller conveyor,and can accurately identify the coding numbers at high production line speeds.The Hmean value of the coding number detection is 97.32%,and the accuracy of the coding number recognition is 98.21%.This verifies that the algorithm proposed in this paper has high accuracy in coding number detection and recognition. 展开更多
关键词 Can coding recognition differentiable binarization network scene visual text recognition model pruning and quantification transport model
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Incorporating red blanket protocol within code crimson:Streamlining definitive trauma care amid the chaos
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作者 Sohil Pothiawala Savitha Bhagvan Andrew MacCormick 《World Journal of Critical Care Medicine》 2025年第1期14-19,共6页
The care of a patient involved in major trauma with exsanguinating haemorrhage is time-critical to achieve definitive haemorrhage control,and it requires coordinated multidisciplinary care.During initial resuscitation... The care of a patient involved in major trauma with exsanguinating haemorrhage is time-critical to achieve definitive haemorrhage control,and it requires coordinated multidisciplinary care.During initial resuscitation of a patient in the emergency department(ED),Code Crimson activation facilitates rapid decisionmaking by multi-disciplinary specialists for definitive haemorrhage control in operating theatre(OT)and/or interventional radiology(IR)suite.Once this decision has been made,there may still be various factors that lead to delay in transporting the patient from ED to OT/IR.Red Blanket protocol identifies and addresses these factors and processes which cause delay,and aims to facilitate rapid and safe transport of the haemodynamically unstable patient from ED to OT,while minimizing delay in resuscitation during the transfer.The two processes,Code Crimson and Red Blanket,complement each other.It would be ideal to merge the two processes into a single protocol rather than having two separate workflows.Introducing these quality improvement strategies and coor-dinated processes within the trauma framework of the hospitals/healthcare systems will help in further improving the multi-disciplinary care for the complex trauma patients requiring rapid and definitive haemorrhage control. 展开更多
关键词 Red blanket protocol code crimson HAEMORRHAGE Trauma
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