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An image joint compression-encryption algorithm based on adaptive arithmetic coding
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作者 邓家先 邓海涛 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期403-408,共6页
Through a series of studies on arithmetic coding and arithmetic encryption, a novel image joint compression- encryption algorithm based on adaptive arithmetic coding is proposed. The contexts produced in the process o... Through a series of studies on arithmetic coding and arithmetic encryption, a novel image joint compression- encryption algorithm based on adaptive arithmetic coding is proposed. The contexts produced in the process of image compression are modified by keys in order to achieve image joint compression encryption. Combined with the bit-plane coding technique, the discrete wavelet transform coefficients in different resolutions can be encrypted respectively with different keys, so that the resolution selective encryption is realized to meet different application needs. Zero-tree coding is improved, and adaptive arithmetic coding is introduced. Then, the proposed joint compression-encryption algorithm is simulated. The simulation results show that as long as the parameters are selected appropriately, the compression efficiency of proposed image joint compression-encryption algorithm is basically identical to that of the original image compression algorithm, and the security of the proposed algorithm is better than the joint encryption algorithm based on interval splitting. 展开更多
关键词 image compression joint compression-encryption algorithm arithmetic encryption progressiveclassification encryption
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An efficient adaptive arithmetic coding image compression technology
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作者 王兴元 云娇娇 张永雷 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期239-245,共7页
This paper proposes an efficient lossless image compression scheme for still images based on an adaptive arithmetic coding compression algorithm. The algorithm increases the image coding compression rate and ensures t... This paper proposes an efficient lossless image compression scheme for still images based on an adaptive arithmetic coding compression algorithm. The algorithm increases the image coding compression rate and ensures the quality of the decoded image combined with the adaptive probability model and predictive coding. The use of adaptive models for each encoded image block dynamically estimates the probability of the relevant image block. The decoded image block can accurately recover the encoded image according to the code book information. We adopt an adaptive arithmetic coding algorithm for image compression that greatly improves the image compression rate. The results show that it is an effective compression technology. 展开更多
关键词 arithmetic coding ADAPTIVE image compression
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A New Method Which Combines Arithmetic Coding with RLE for Lossless Image Compression
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作者 Med Karim Abdmouleh Atef Masmoudi Med Salim Bouhlel 《Journal of Software Engineering and Applications》 2012年第1期41-44,共4页
This paper presents a new method of lossless image compression. An image is characterized by homogeneous parts. The bit planes, which are of high weight are characterized by sequences of 0 and 1 are successive encoded... This paper presents a new method of lossless image compression. An image is characterized by homogeneous parts. The bit planes, which are of high weight are characterized by sequences of 0 and 1 are successive encoded with RLE, whereas the other bit planes are encoded by the arithmetic coding (AC) (static or adaptive model). By combining an AC (adaptive or static) with the RLE, a high degree of adaptation and compression efficiency is achieved. The proposed method is compared to both static and adaptive model. Experimental results, based on a set of 12 gray-level images, demonstrate that the proposed scheme gives mean compression ratio that are higher those compared to the conventional arithmetic encoders. 展开更多
关键词 Adaptive arithmetic CODING Static arithmetic CODING arithmetic CODING LOSSLESS compression Image RUN Length ENCODING
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Medical Image Compression Using Wrapping Based Fast Discrete Curvelet Transform and Arithmetic Coding
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作者 P. Anandan R. S. Sabeenian 《Circuits and Systems》 2016年第8期2059-2069,共11页
Due to the development of CT (Computed Tomography), MRI (Magnetic Resonance Imaging), PET (Positron Emission Tomography), EBCT (Electron Beam Computed Tomography), SMRI (Stereotactic Magnetic Resonance Imaging), etc. ... Due to the development of CT (Computed Tomography), MRI (Magnetic Resonance Imaging), PET (Positron Emission Tomography), EBCT (Electron Beam Computed Tomography), SMRI (Stereotactic Magnetic Resonance Imaging), etc. has enhanced the distinguishing rate and scanning rate of the imaging equipments. The diagnosis and the process of getting useful information from the image are got by processing the medical images using the wavelet technique. Wavelet transform has increased the compression rate. Increasing the compression performance by minimizing the amount of image data in the medical images is a critical task. Crucial medical information like diagnosing diseases and their treatments is obtained by modern radiology techniques. Medical Imaging (MI) process is used to acquire that information. For lossy and lossless image compression, several techniques were developed. Image edges have limitations in capturing them if we make use of the extension of 1-D wavelet transform. This is because wavelet transform cannot effectively transform straight line discontinuities, as well geographic lines in natural images cannot be reconstructed in a proper manner if 1-D transform is used. Differently oriented image textures are coded well using Curvelet Transform. The Curvelet Transform is suitable for compressing medical images, which has more curvy portions. This paper describes a method for compression of various medical images using Fast Discrete Curvelet Transform based on wrapping technique. After transformation, the coefficients are quantized using vector quantization and coded using arithmetic encoding technique. The proposed method is tested on various medical images and the result demonstrates significant improvement in performance parameters like Peak Signal to Noise Ratio (PSNR) and Compression Ratio (CR). 展开更多
关键词 Medical Image compression Discrete Curvelet Transform Fast Discrete Curvelet Transform arithmetic Coding Peak Signal to Noise Ratio compression Ratio
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Explainable Data-Driven Modeling for Optimized Mix Design of 3D-Printed Concrete: Interpreting Nonlinear Synergies among Binder Components and Proportions
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作者 Yassir M.Abbas Abdulaziz Alsaif 《Computer Modeling in Engineering & Sciences》 2025年第11期1789-1819,共31页
The rapid advancement of three-dimensional printed concrete(3DPC)requires intelligent and interpretable frameworks to optimize mixture design for strength,printability,and sustainability.While machine learning(ML)mode... The rapid advancement of three-dimensional printed concrete(3DPC)requires intelligent and interpretable frameworks to optimize mixture design for strength,printability,and sustainability.While machine learning(ML)models have improved predictive accuracy,their limited transparency has hindered their widespread adoption in materials engineering.To overcome this barrier,this study introduces a Random Forests ensemble learning model integrated with SHapley Additive exPlanations(SHAP)and Partial Dependence Plots(PDPs)to model and explain the compressive strength behavior of 3DPC mixtures.Unlike conventional“black-box”models,SHAP quantifies each variable’s contribution to predictions based on cooperative game theory,which enables causal interpretability,whereas PDP visualizes nonlinear and interactive effects between features that offer practical mix design insights.A systematically optimized random forest model achieved strong generalization(R2=0.978 for training,0.834 for validation,and 0.868 for testing).The analysis identified curing age,Portland cement,silica fume,and the water-tobinder ratio as dominant predictors,with curing age exerting the highest positive influence on strength development.The integrated SHAP-PDP framework revealed synergistic interactions among binder constituents and curing parameters,which established transparent,data-driven guidelines for performance optimization.Theoretically,the study advances explainable artificial intelligence in cementitious material science by linking microstructural mechanisms to model-based reasoning,thereby enhancing both the interpretability and applicability of ML-driven mix design for next-generation 3DPC systems. 展开更多
关键词 3D-printed concrete compressive strength machine learning mix design optimization partial dependence plots
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Degree-Preserving Distance Compression and Topological Compressibility of Complex Networks
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作者 Jian-Hui Li Zu-Guo Yu Yu-Chu Tian 《Chinese Physics Letters》 2025年第12期24-32,共9页
Accurately modeling real network dynamics is a grand challenge in network science.The network dynamics arise from node interactions,which are shaped by network topology.Real networks tend to exhibit compact or highly ... Accurately modeling real network dynamics is a grand challenge in network science.The network dynamics arise from node interactions,which are shaped by network topology.Real networks tend to exhibit compact or highly optimized topologies.But the key problems arise:how to compress a network to best enhance its compactness,and what the compression limit of the network reflects?We abstract the topological compression of complex networks as a dynamic process of making them more compact and propose the local compression modulus that plays a key role in effective compression evolution of networks.Subsequently,we identify topological compressibility-a general property of complex networks that characterizes the extent to which a network can be compressed-and provide its approximate quantification.We anticipate that our findings and established theory will provide valuable insights into both dynamics and various applications of complex networks. 展开更多
关键词 local compr topological compression node interactionswhich network topologyreal accurately modeling real network dynamics compact highly optimized topologiesbut complex networks network dynamics
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面向燃烧闭环控制的天然气掺氢发动机CA50预测
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作者 段浩 曾笑笑 +2 位作者 尹晓军 胡二江 曾科 《同济大学学报(自然科学版)》 北大核心 2026年第2期296-304,共9页
为探究提高发动机效率和降低排放的方法,开展了燃烧闭环控制关键参数CA50对天然气掺氢混合燃料(HCNG)发动机燃烧和排放影响的试验研究,并基于试验结果对CA50进行统计分析。利用粒子群优化反向传播神经网络(PSO-BPNN)算法对CA50进行预测... 为探究提高发动机效率和降低排放的方法,开展了燃烧闭环控制关键参数CA50对天然气掺氢混合燃料(HCNG)发动机燃烧和排放影响的试验研究,并基于试验结果对CA50进行统计分析。利用粒子群优化反向传播神经网络(PSO-BPNN)算法对CA50进行预测,并探究了混合策略优化对PSO-BPNN模型预测性能的影响。结果表明,CA50对HCNG发动机的燃烧特性和排放有显著影响;CA50服从正态分布,不存在自相关,可作为燃烧闭环控制的反馈参数;通过PSO-BPNN方法建立的CA50预测模型具有较高的预测性能和良好的泛化能力,平均绝对误差为0.25°CA,相关系数大于0.997;混合策略可在不降低预测精度的情况下显著提高模型的收敛速度,CPU运行时间最多可缩短73.02%。 展开更多
关键词 燃烧闭环控制 燃烧特性 粒子群优化 人工神经网络 天然气掺氢
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High temperature deformation behavior and optimization of hot compression process parameters in TC11 titanium alloy with coarse lamellar original microstructure 被引量:5
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作者 鲁世强 李鑫 +2 位作者 王克鲁 董显娟 傅铭旺 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期353-360,共8页
The high temperature deformation behaviors of α+β type titanium alloy TC11 (Ti-6.5Al-3.5Mo-1.5Zr-0.3Si) with coarse lamellar starting microstructure were investigated based on the hot compression tests in the tem... The high temperature deformation behaviors of α+β type titanium alloy TC11 (Ti-6.5Al-3.5Mo-1.5Zr-0.3Si) with coarse lamellar starting microstructure were investigated based on the hot compression tests in the temperature range of 950-1100 ℃ and the strain rate range of 0.001-10 s-1. The processing maps at different strains were then constructed based on the dynamic materials model, and the hot compression process parameters and deformation mechanism were optimized and analyzed, respectively. The results show that the processing maps exhibit two domains with a high efficiency of power dissipation and a flow instability domain with a less efficiency of power dissipation. The types of domains were characterized by convergence and divergence of the efficiency of power dissipation, respectively. The convergent domain in a+fl phase field is at the temperature of 950-990 ℃ and the strain rate of 0.001-0.01 s^-1, which correspond to a better hot compression process window of α+β phase field. The peak of efficiency of power dissipation in α+β phase field is at 950 ℃ and 0.001 s 1, which correspond to the best hot compression process parameters of α+β phase field. The convergent domain in β phase field is at the temperature of 1020-1080 ℃ and the strain rate of 0.001-0.1 s^-l, which correspond to a better hot compression process window of β phase field. The peak of efficiency of power dissipation in ℃ phase field occurs at 1050 ℃ over the strain rates from 0.001 s^-1 to 0.01 s^-1, which correspond to the best hot compression process parameters of ,8 phase field. The divergence domain occurs at the strain rates above 0.5 s^-1 and in all the tested temperature range, which correspond to flow instability that is manifested as flow localization and indicated by the flow softening phenomenon in stress-- strain curves. The deformation mechanisms of the optimized hot compression process windows in a+β and β phase fields are identified to be spheroidizing and dynamic recrystallizing controlled by self-diffusion mechanism, respectively. The microstructure observation of the deformed specimens in different domains matches very well with the optimized results. 展开更多
关键词 titanium alloy coarse lamellar microstructure high temperature deformation behavior processing map hot compression process parameter optimization
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基于移动车辆荷载作用下锚固点振动响应结合机器学习的斜拉索损伤识别研究
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作者 曾有艺 杜家锐 +2 位作者 张家滨 王金昊 樊继荣 《中外公路》 2026年第1期177-187,共11页
移动车辆荷载作用下采集的桥面振动响应数据,包含了很多桥梁的几何参数信息,能有效地对结构损伤进行识别。机器学习算法能够挖掘响应数据中的关键信息,捕捉其中线性关系。该文以韶州大桥为背景,建立斜拉桥有限元模型,将多种不同车辆参... 移动车辆荷载作用下采集的桥面振动响应数据,包含了很多桥梁的几何参数信息,能有效地对结构损伤进行识别。机器学习算法能够挖掘响应数据中的关键信息,捕捉其中线性关系。该文以韶州大桥为背景,建立斜拉桥有限元模型,将多种不同车辆参数的两轴货车荷载作用在不同斜拉索小损伤工况下的斜拉桥模型上,模拟计算移动荷载作用下斜拉桥模型的振动响应。采用主成分分析(PCA)技术对加速度数据降维压缩,并结合贝叶斯优化后的最小二乘法支持向量机模型(BO-LSSVM),开展不同荷载组合下斜拉索的损伤定位与定量分析。针对多根拉索损伤预测不准确的情况,提出了将定位标签整合到损伤数据中的方法。结果表明:基于大量的损伤响应数据,BO-LSSVM模型能寻找到最佳的超参数组合,有效分析复杂响应数据,利用移动车辆荷载实现拉索损伤程度的监测分析。利用PCA对加速度响应数据进行降维压缩,在保证预测精准度的同时,提高了机器学习的计算效率,节约了计算资源。且在多损伤数据特征数据中添加定位标签方法有效提高了损伤识别的准确性。该研究为实际工程中的损伤实时监测提供了模型参考与技术理论基础。 展开更多
关键词 斜拉桥 车桥耦合 振动响应 数据压缩 贝叶斯优化 最小二乘法支持向量机 损伤识别
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Zstandard中LZ77压缩算法的高效匹配策略设计与实现
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作者 韦芳宇 陈天韵 +2 位作者 周洋 谢雨来 王芳 《计算机研究与发展》 北大核心 2026年第3期597-614,共18页
在信息时代背景下,数据规模的急剧增长与压缩应用场景的多样化,对压缩策略的灵活性和效率提出了更高要求。LZ77算法是典型的无损压缩方法,广泛应用于Zstandard(ZSTD)等主流压缩工具中。然而,更高的压缩率指标要求应用更大的历史窗口与... 在信息时代背景下,数据规模的急剧增长与压缩应用场景的多样化,对压缩策略的灵活性和效率提出了更高要求。LZ77算法是典型的无损压缩方法,广泛应用于Zstandard(ZSTD)等主流压缩工具中。然而,更高的压缩率指标要求应用更大的历史窗口与更复杂的压缩策略,导致在实现ZSTD中的LZ77算法存在缓存频繁未命中与延迟匹配效率低下的问题。为此,提出2项优化策略:其一,多级区域搜索策略(multi-level region search strategy,MLRS),通过引入匹配区域分级与访问阈值控制机制灵活调整搜索深度,限制匹配过程中的数据访问范围,缓解缓存压力;其二,基于扩展搜索的延迟匹配策略(extended searchbased lazy matching strategy,ESLM),通过复用搜索路径并采用近似替代技术,降低冗余计算的同时提升匹配效率。上述优化策略基于ZSTD level 12配置在鲲鹏920服务器平台上实现并完成验证。实验结果表明:MLRS在多种数据集上能够显著降低压缩过程中的末级缓存未命中率,将压缩率保持在94.65%~99.58%的同时,使压缩吞吐量提升至原方案的118.34%~149.50%;ESLM可将压缩吞吐量提升至原方案的113.49%~117.46%,且在多数数据集上进一步提高压缩比;当两者联合应用时,压缩速度可提升至原方案的134.53%~171.17%,同时维持94.18%~99.80%的压缩率。 展开更多
关键词 数据压缩 LZ77算法 缓存优化 延迟匹配 吞吐量优化
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独立式液态空气储能系统压缩热利用优化研究
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作者 王新东 李宜洪 +2 位作者 李博 高健 王俊杰 《热力发电》 北大核心 2026年第2期49-57,共9页
构建了一套水-油组合蓄热的独立式液态空气储能系统,并分析了系统中压缩级数、膨胀级数以及蓄热水温度对系统往返效率和压缩热利用程度的影响规律。研究结果表明:压缩级数的增加导致往返效率降低,最优压缩级数为2级;在不同压缩级数条件... 构建了一套水-油组合蓄热的独立式液态空气储能系统,并分析了系统中压缩级数、膨胀级数以及蓄热水温度对系统往返效率和压缩热利用程度的影响规律。研究结果表明:压缩级数的增加导致往返效率降低,最优压缩级数为2级;在不同压缩级数条件下,最佳膨胀级数比压缩级数多一级;在25~65℃,提高蓄热水温度能够提升系统往返效率和压缩热的利用程度,但当蓄热水温度超过65℃,系统效率不再继续提升;在最优化条件下,采用2级压缩、3级膨胀以及65℃蓄热水温的系统压缩热富余比例为0.349,往返效率达到0.622。本研究可为液态空气储能系统的压缩热利用过程优化提供理论依据。 展开更多
关键词 液态空气储能 压缩热 蓄热过程 效率优化
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聚丙烯酸丁酯-丙烯酸/水玻璃复合改性淤泥的流变特性与力学性能
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作者 鲁依萍 黄修林 +1 位作者 周紫晨 刘仕琪 《硅酸盐通报》 北大核心 2026年第1期325-335,共11页
本文以丙烯酸丁酯(BA)、丙烯酸(AA)和水玻璃为主要原料,十二烷基硫酸钠(SDS)和烷基酚聚氧乙烯醚(OP-10)为复合乳化剂,采用预乳化半连续种子乳液聚合法合成复合土壤固化剂(PBA),通过正交试验研究了水玻璃模数、固化剂掺量及水土比对PBA... 本文以丙烯酸丁酯(BA)、丙烯酸(AA)和水玻璃为主要原料,十二烷基硫酸钠(SDS)和烷基酚聚氧乙烯醚(OP-10)为复合乳化剂,采用预乳化半连续种子乳液聚合法合成复合土壤固化剂(PBA),通过正交试验研究了水玻璃模数、固化剂掺量及水土比对PBA固化土无侧限抗压强度的影响。FT-IR结果分析表明,BA、AA和水玻璃三种单体均参与反应。当水玻璃模数为2.2、固化剂掺量为4%(质量分数)、水土比为0.44时,PBA固化土性能最优,流动度达到132 mm,7 d无侧限抗压强度为1.37 MPa。 展开更多
关键词 聚丙烯酸酯 乳液聚合 土壤固化剂 固化土 无侧限抗压强度 最佳掺量
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神经网络滤波器剪枝技术研究综述
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作者 王琳 宋权润 +1 位作者 耿世超 栾钟治 《计算机工程与应用》 北大核心 2026年第2期1-25,共25页
随着软硬件资源水平和计算能力的提高,深度神经网络在计算机视觉、自然语言处理、图像生成等多个领域迅速发展,引领深度学习在自动驾驶、医疗诊断等方向上不断突破。然而,随着模型深度的增加,庞大的参数量和计算资源消耗导致模型变得过... 随着软硬件资源水平和计算能力的提高,深度神经网络在计算机视觉、自然语言处理、图像生成等多个领域迅速发展,引领深度学习在自动驾驶、医疗诊断等方向上不断突破。然而,随着模型深度的增加,庞大的参数量和计算资源消耗导致模型变得过于复杂,难以在资源受限的环境进行训练和部署。为了减少网络模型的复杂度,提高模型的效率,研究者们提出了剪枝方法,通过减少模型中的冗余参数和连接实现模型的压缩和加速。滤波器剪枝是优化卷积神经网络的重要方法之一,通过改变网络中滤波器组和特征通道的数目来加速网络,且不依赖于特定算法或硬件平台。梳理了近年来国内外滤波器剪枝技术的研究进展,从滤波器重要性评估、剪枝及微调方式设计两个方面进行分类总结,并对主流滤波器剪枝方法的实验进行归纳,分析滤波器剪枝对模型精度和参数量的影响,并对未来的研究方向加以探讨。 展开更多
关键词 深度学习 深度卷积神经网络 模型压缩 滤波器剪枝 模型优化加速
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基于堆叠集成学习混合方法的钢纤维混凝土抗压强度预测与应用
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作者 刘伟铧 程海勇 +5 位作者 吴顺川 向天兵 任子健 孙俊龙 孟琴 奎盖 《工程科学学报》 北大核心 2026年第2期262-273,共12页
随着现代工程对材料性能要求不断提高,钢纤维混凝土(SFRC)作为一种具有优异力学性能和耐久性的复合材料,在工程中得到了广泛的应用.钢纤维混凝土的抗压强度是衡量其性能的关键指标.通过室内试验对钢纤维混凝土的抗压强度进行测试,往往... 随着现代工程对材料性能要求不断提高,钢纤维混凝土(SFRC)作为一种具有优异力学性能和耐久性的复合材料,在工程中得到了广泛的应用.钢纤维混凝土的抗压强度是衡量其性能的关键指标.通过室内试验对钢纤维混凝土的抗压强度进行测试,往往需要花费大量的人力物力,且养护周期较长.基于此,提出了一种基于堆叠集成学习的钢纤维混凝土抗压强度预测模型.基于收集到的211组不同的钢纤维混凝土配合比数据,选用SVM、DT、KNN、RF和BP 5种单一模型进行堆叠集成学习.同时,使用6种优化算法对5种单一模型进行优化,最终得到OP-Stacking混合模型.使用OP-Stacking混合模型对钢纤维混凝土7天抗压强度进行预测,MSE和R^(2)分别为96.4937和0.9332,均优于其他5种单一模型.同时,将钢纤维混凝土7天、28天的抗压强度进行线性拟合,得到了7天、28天强度的经验公式.最后,将OP-Stacking混合模型与7天、28天强度经验公式进行了封装,建立了钢纤维混凝土强度预测系统和智能配比设计,为滇中引水工程新型支护设计快速施工提供了重要支持. 展开更多
关键词 集成学习 钢纤维混凝土 抗压强度预测 优化算法 智能配比设计
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基于随机森林与Q-learning融合的多元电力数据存储优化决策方法
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作者 叶学顺 贾东梨 +2 位作者 周俊 唐英 贾梓豪 《科学技术与工程》 北大核心 2026年第3期1065-1074,共10页
大规模和多样的电力数据存储面临效率低和内存容量不足的瓶颈问题。数据索引和数据压缩等传统数据存储优化方法各有优劣势,如何有效应用于电力数据存储是目前研究的难点。为了解决这个问题,提出了一种融合随机森林和Q-learning的多元电... 大规模和多样的电力数据存储面临效率低和内存容量不足的瓶颈问题。数据索引和数据压缩等传统数据存储优化方法各有优劣势,如何有效应用于电力数据存储是目前研究的难点。为了解决这个问题,提出了一种融合随机森林和Q-learning的多元电力数据存储优化决策方法。该方法中的关键技术包括:首先提出了基于改进随机森林算法的存储优化策略决策模型,引入信息增益方法,综合评价数据存储时对数据库的数据访问频率、查询时间、存储速度以及数据冗余率等因素影响,做出数据直接存储、数据索引存储和数据压缩存储的存储优化方法策略决策;其次提出了基于改进Q-learning算法的数据存储算法决策模型,引入多尺度学习机制、优先经验放回机制和正负向奖励机制,决策数据索引存储时适用的索引算法以及数据压缩存储时适用的数据压缩算法。本方法有效融合了数据索引与数据压缩的技术优势,大幅提升数据存储效率并节约存储空间,为大规模多元电力数据管理提供新的解决方案。 展开更多
关键词 随机森林算法 Q-learning算法 数据存储优化方法 数据索引算法 数据压缩算法
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室内空调挂机的包装结构设计
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作者 方景丽 肖颖喆 张涵玥 《包装学报》 2026年第2期85-93,共9页
针对室内空调挂机包装箱长宽比过大导致抗压强度衰减、储运过程中易发生鼓包或内凹等行业难题,通过结构创新探寻高抗压强度瓦楞纸箱成为研究重点。从结构失效机理出发,将04型箱选定为关键研究对象,进而选取典型的0201型、0203型及0440... 针对室内空调挂机包装箱长宽比过大导致抗压强度衰减、储运过程中易发生鼓包或内凹等行业难题,通过结构创新探寻高抗压强度瓦楞纸箱成为研究重点。从结构失效机理出发,将04型箱选定为关键研究对象,进而选取典型的0201型、0203型及0440型改良箱,分别采用普通与加强的5层BC楞纸板制作样本,系统进行了边压强度、空箱抗压及模拟真实仓储堆叠实验,并结合力学性能、成本及生产工艺进行多维度综合评价。实验表明,0440型改良箱凭借整板底板与多重受力板结构,展现出最优的抗压强度,能从本质上解决箱体长边薄弱问题,适合对包装强度要求较高的高端应用。0201型箱加装U型支撑板后,抗压强度亦显著提升,其抗压效率明显优于普通0201型箱与0203型箱,在常规应用场景中具有较高的性价比。上述结论为空调挂机包装的结构选型提供了数据支持与决策依据。 展开更多
关键词 瓦楞纸箱 包装结构设计 结构优化 抗压强度
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基于贝叶斯理论的地聚物混凝土抗压强度预测及配合比优化
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作者 仇彤 周剑 +2 位作者 张晓腾 吕佼佼 谢波 《特种结构》 2026年第1期7-12,32,共7页
为了提高地聚物混凝土抗压强度预测精度及配合比的优化方法,本文提出一种基于贝叶斯理论的地聚物混凝土抗压强度预测方法及配合比优化方法。结合收集的179组试验数据采用贝叶斯后验估计方法对已有的混凝土预测模型进行修正,建立了地聚... 为了提高地聚物混凝土抗压强度预测精度及配合比的优化方法,本文提出一种基于贝叶斯理论的地聚物混凝土抗压强度预测方法及配合比优化方法。结合收集的179组试验数据采用贝叶斯后验估计方法对已有的混凝土预测模型进行修正,建立了地聚物混凝土抗压强度预测模型,并通过对影响因素的显著性分析剔除部分参数简化预测模型,最后采用遗传算法对C30~C60地聚物混凝土配合比进行优化设计。结果表明:地聚物混凝土抗压强度主要受水灰比、水胶比、碱激发剂模数、养护龄期、养护温度和骨料含量等因素的影响;提出的简易模型具有较高的预测精度,为地聚物混凝土抗压强度预测提供新思路。 展开更多
关键词 地聚物混凝土 贝叶斯理论 抗压强度 配合比优化 预测模型
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Action Recognition via Shallow CNNs on Intelligently Selected Motion Data
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作者 Jalees Ur Rahman Muhammad Hanif +2 位作者 Usman Haider Saeed Mian Qaisar Sarra Ayouni 《Computers, Materials & Continua》 2026年第3期2223-2243,共21页
Deep neural networks have achieved excellent classification results on several computer vision benchmarks.This has led to the popularity of machine learning as a service,where trained algorithms are hosted on the clou... Deep neural networks have achieved excellent classification results on several computer vision benchmarks.This has led to the popularity of machine learning as a service,where trained algorithms are hosted on the cloud and inference can be obtained on real-world data.In most applications,it is important to compress the vision data due to the enormous bandwidth and memory requirements.Video codecs exploit spatial and temporal correlations to achieve high compression ratios,but they are computationally expensive.This work computes the motion fields between consecutive frames to facilitate the efficient classification of videos.However,contrary to the normal practice of reconstructing the full-resolution frames through motion compensation,this work proposes to infer the class label from the block-based computed motion fields directly.Motion fields are a richer and more complex representation of motion vectors,where each motion vector carries the magnitude and direction information.This approach has two advantages:the cost of motion compensation and video decoding is avoided,and the dimensions of the input signal are highly reduced.This results in a shallower network for classification.The neural network can be trained using motion vectors in two ways:complex representations and magnitude-direction pairs.The proposed work trains a convolutional neural network on the direction and magnitude tensors of the motion fields.Our experimental results show 20×faster convergence during training,reduced overfitting,and accelerated inference on a hand gesture recognition dataset compared to full-resolution and downsampled frames.We validate the proposed methodology on the HGds dataset,achieving a testing accuracy of 99.21%,on the HMDB51 dataset,achieving 82.54%accuracy,and on the UCF101 dataset,achieving 97.13%accuracy,outperforming state-of-the-art methods in computational efficiency. 展开更多
关键词 Action recognition block matching algorithm convolutional neural network deep learning data compression motion fields optimization videos classification
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A Hybrid Experimental-Numerical Framework for Identifying Viscoelastic Parameters of 3D-Printed Polyurethane Samples:Cyclic Tests,Creep/Relaxation and Inverse Finite Element Analysis
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作者 Nikita Golovkin Olesya Nikulenkova +4 位作者 Vsevolod Pobezhimov Alexander Nesmelov Sergei Chvalun Fedor Sorokin Arthur Krupnin 《Computers, Materials & Continua》 2026年第3期519-536,共18页
This study presents and verifies a hybrid methodology for reliable determination of parameters in structural rheological models(Zener,Burgers,and Maxwell)describing the viscoelastic behavior of polyurethane specimens ... This study presents and verifies a hybrid methodology for reliable determination of parameters in structural rheological models(Zener,Burgers,and Maxwell)describing the viscoelastic behavior of polyurethane specimens manufactured using extrusion-based 3D printing.Through comprehensive testing,including cyclic compression at strain rates ranging from 0.12 to 120 mm/min(0%-15%strain)and creep/relaxation experiments(10%-30%strain),the lumped parameters were independently determined using both analytical and numerical solutions of the models’differential equations,followed by cross-verification in additional experiments.Numerical solutions for creep and relaxation problems were obtained using finite element analysis,with the three-parameter Mooney-Rivlin model and Prony series employed to simulate elastic and viscous stress components,respectively.Energy dissipation per cycle was quantified during cyclic compression tests.The results demonstrate that all three models adequately describe material behavior within the 0%-15%strain range across various strain rates.Comparative analysis revealed the Burgers model’s superior performance in characterizing creep and stress relaxation at low strain levels.While Zener and Burgers model parameters from uniaxial compression showed limited applicability for energy dissipation calculations,the generalized Maxwell model effectively captured viscoelastic properties across different strain rates.Notably,parameters derived from creep tests provided a more universal assessment of dissipative properties due to optimization based on characteristic curve regions.Both parameter sets described polyurethane’s elastic-hysteretic behavior with approximately 20%error,proving significantly more accurate than the linear strain-time dependence hypothesis.Finite element analysis(FEA)complemented numerical modeling by demonstrating that while the generalized Maxwell model effectively describes initial rapid stress-strain changes,FEA provides superior characterization of steady-state processes.This computational approach yields more physically representative results compared to simplified analytical solutions,despite certain limitations in transient analysis. 展开更多
关键词 VISCOELASTICITY cyclic compression HYSTERESIS CREEP stress relaxation finite element method optimization 3D printing structural rheological models Prony series
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Explainable AI for predicting the strength of bio-cemented sands
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作者 Waleed El-Sekelly Muhammad Nouman Amjad Raja Tarek Abdoun 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1552-1569,共18页
The biological stabilization of soil using microbially induced carbonate precipitation(MICP)employs ureolytic bacteria to precipitate calcium carbonate(CaCO3),which binds soil particles,enhancing strength,stiffness,an... The biological stabilization of soil using microbially induced carbonate precipitation(MICP)employs ureolytic bacteria to precipitate calcium carbonate(CaCO3),which binds soil particles,enhancing strength,stiffness,and erosion resistance.The unconfinedcompressive strength(UCS),a key measure of soil strength,is critical in geotechnical engineering as it directly reflectsthe mechanical stability of treated soils.This study integrates explainable artificialintelligence(XAI)with geotechnical insights to model the UCS of MICP-treated sands.Using 517 experimental data points and a combination of various input variables—including median grain size(D50),coefficientof uniformity(Cu),void ratio(e),urea concentration(Mu),calcium concentration(Mc),optical density(OD)of bacterial solution,pH,and total injection volume(Vt)—fivemachine learning(ML)models,including eXtreme gradient boosting(XGBoost),Light gradient boosting machine(LightGBM),random forest(RF),gene expression programming(GEP),and multivariate adaptive regression splines(MARS),were developed and optimized.The ensemble models(XGBoost,LightGBM,and RF)were optimized using the Chernobyl disaster optimizer(CDO),a recently developed metaheuristic algorithm.Of these,LightGBM-CDO achieved the highest accuracy for UCS prediction.XAI techniques like feature importance analysis(FIA),SHapley additive exPlanations(SHAP),and partial dependence plots(PDPs)were also used to investigate the complex non-linear relationships between the input and output variables.The results obtained have demonstrated that the XAI-driven models can enhance the predictive accuracy and interpretability of MICP processes,offering a sustainable pathway for optimizing geotechnical applications. 展开更多
关键词 Microbially induced carbonate precipitation(MICP) Bio-cementation Unconfined compressive strength(UCS) Explainable artificialintelligence(XAI) Optimization
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