This paper reviewed the recent progress in the field of electrocardiogram (ECG) compression and compared the efficiency of some compression algorithms. By experimenting on the 500 cases of ECG signals from the ECG dat...This paper reviewed the recent progress in the field of electrocardiogram (ECG) compression and compared the efficiency of some compression algorithms. By experimenting on the 500 cases of ECG signals from the ECG database of China, it obtained the numeral indexes for each algorithm. Then by using the automatic diagnostic program developed by Shanghai Zhongshan Hospital, it also got the parameters of the reconstructed signals from linear approximation distance threshold (LADT), wavelet transform (WT), differential pulse code modulation (DPCM) and discrete cosine transform (DCT) algorithm. The results show that when the index of percent of root mean square difference(PRD) is less than 2.5%, the diagnostic agreement ratio is more than 90%; the index of PRD cannot completely show the damage of significant clinical information; the performance of wavelet algorithm exceeds other methods in the same compression ratio (CR). For the statistical result of the parameters of various methods and the clinical diagnostic results, it is of certain value and originality in the field of ECG compression research.展开更多
Integrated building design is inherently a multi-objective optimization problem where two or more conflicting objectives must be minimized and/or maximized concurrently.Many multi-objective optimization algorithms hav...Integrated building design is inherently a multi-objective optimization problem where two or more conflicting objectives must be minimized and/or maximized concurrently.Many multi-objective optimization algorithms have been developed;however few of them are tested in solving building design problems.This paper compares performance of seven commonly-used multi-objective evolutionary optimization algorithms in solving the design problem of a nearly zero energy building(n ZEB) where more than 1.610 solutions would be possible.The compared algorithms include a controlled non-dominated sorting genetic algorithm witha passive archive(p NSGA-II),a multi-objective particle swarm optimization(MOPSO),a two-phase optimization using the genetic algorithm(PR_GA),an elitist non-dominated sorting evolution strategy(ENSES),a multi-objective evolutionary algorithm based on the concept of epsilon dominance(ev MOGA),a multi-objective differential evolution algorithm(sp MODE-II),and a multi-objective dragonfly algorithm(MODA).Several criteria was used to compare performance of these algorithms.In most cases,the quality of the obtained solutions was improved when the number of generations was increased.The optimization results of running each algorithm20 times with gradually increasing number of evaluations indicated that the PR_GA algorithm had a high repeatability to explore a large area of the solution-space and achieved close-to-optimal solutions with a good diversity,followed by the p NSGA-II,ev MOGA and sp MODE-II.Uncompetitive results were achieved by the ENSES,MOPSO and MODA in most running cases.The study also found that 1400-1800 were minimum required number of evaluations to stabilize optimization results of the building energy model.展开更多
Discrete curves are composed of a set of ordered discrete points distributed at the intersection of the scanning plane and the surface of the object. In order to accurately calculate the geometric characteristics of a...Discrete curves are composed of a set of ordered discrete points distributed at the intersection of the scanning plane and the surface of the object. In order to accurately calculate the geometric characteristics of any point on the discrete curve, a distance-based Gaussian weighted algorithm is proposed to estimate the geometric characteristics of three-dimensional space discrete curves. According to the definition of discrete derivatives, the algorithm fully considers the relative position difference between a specific point and its neighboring points, introduces the distance weighting idea, and integrates the smoothing strategy. The experiment uses two spatial discrete curves for uniform and non-uniform sampling, and compares them with two commonly used estimation algorithms. The comparative analysis is carried out in terms of sampling density, neighborhood radius and noise resistance. The experimental results show that the Gaussian distance weighted algorithm is effective and provides an efficient algorithm for underground pipeline safety detection.展开更多
随着大语言模型(Large Language Model,LLM)技术的快速发展,高校图书馆分类编目面临智能化升级需求。为解决传统分类编目流程中效率偏低、标准适配滞后、复杂文献处理困难等问题,文章聚焦Transformer核心算法、预训练-微调算法、检索增...随着大语言模型(Large Language Model,LLM)技术的快速发展,高校图书馆分类编目面临智能化升级需求。为解决传统分类编目流程中效率偏低、标准适配滞后、复杂文献处理困难等问题,文章聚焦Transformer核心算法、预训练-微调算法、检索增强生成算法、人机协同反馈算法等主流算法,从分类、编目著录、数据校验与入库、后续维护等方面分析各算法的优势、劣势及效率表现。通过多维度测评发现,检索增强生成(Retrieval-Augmented Generation,RAG)算法凭借规则适配性强、知识更新高效的特点,适配综合性大学、专门学院及中等规模高校图书馆需求;人机协同反馈(Human-in-the-Loop,HITL)算法以极致准确率与风险可控性,成为研究型高校及馆藏珍贵文献图书馆的最优选择。文章构建的算法适配框架与选型建议,为高校图书馆分类编目智能化转型提供理论参考与实践指导,助力提升编目质量与资源利用效率。展开更多
摘要This paper reviewed the recent progress in the field of electrocardiogram (ECG) compression and compared the efficiency of some compression algorithms. By experimenting on the 500 cases of ECG signals from the ECG database of China, it obtained the numeral indexes for each algorithm. Then by using the automatic diagnostic program developed by Shanghai Zhongshan Hospital, it also got the parameters of the reconstructed signals from linear approximation distance threshold (LADT), wavelet transform (WT), differential pulse code modulation (DPCM) and discrete cosine transform (DCT) algorithm. The results show that when the index of percent of root mean square difference(PRD) is less than 2.5%, the diagnostic agreement ratio is more than 90%; the index of PRD cannot completely show the damage of significant clinical information; the performance of wavelet algorithm exceeds other methods in the same compression ratio (CR). For the statistical result of the parameters of various methods and the clinical diagnostic results, it is of certain value and originality in the field of ECG compression research.
摘要Integrated building design is inherently a multi-objective optimization problem where two or more conflicting objectives must be minimized and/or maximized concurrently.Many multi-objective optimization algorithms have been developed;however few of them are tested in solving building design problems.This paper compares performance of seven commonly-used multi-objective evolutionary optimization algorithms in solving the design problem of a nearly zero energy building(n ZEB) where more than 1.610 solutions would be possible.The compared algorithms include a controlled non-dominated sorting genetic algorithm witha passive archive(p NSGA-II),a multi-objective particle swarm optimization(MOPSO),a two-phase optimization using the genetic algorithm(PR_GA),an elitist non-dominated sorting evolution strategy(ENSES),a multi-objective evolutionary algorithm based on the concept of epsilon dominance(ev MOGA),a multi-objective differential evolution algorithm(sp MODE-II),and a multi-objective dragonfly algorithm(MODA).Several criteria was used to compare performance of these algorithms.In most cases,the quality of the obtained solutions was improved when the number of generations was increased.The optimization results of running each algorithm20 times with gradually increasing number of evaluations indicated that the PR_GA algorithm had a high repeatability to explore a large area of the solution-space and achieved close-to-optimal solutions with a good diversity,followed by the p NSGA-II,ev MOGA and sp MODE-II.Uncompetitive results were achieved by the ENSES,MOPSO and MODA in most running cases.The study also found that 1400-1800 were minimum required number of evaluations to stabilize optimization results of the building energy model.
摘要目的基于机器学习构建高精度、可解释性好的后路腰椎椎体间融合术后慢性疼痛(chronic post-surgical pain,CPSP)风险预测模型,为临床早期识别高危人群、实现精准预防提供可靠工具。方法回顾性分析2019年1月至2023年12月在我院行后路腰椎椎体间融合术患者759例,其中男375例,女384例,33~80(55.28±9.94)岁。按7∶3比例分层随机分为训练集(n=531)和测试集(n=228)。收集所有患者术前、术中、术后共40项特征数据。行数据预处理和LASSO回归特征筛选后,构建7种机器学习模型,以受试者工作特征曲线下面积(area under the curve,AUC)、F1分数等作为核心指标筛选模型,使用沙普利加法解释(Shapley additive explanations,SHAP)工具对其进行可解释性分析。结果最终筛选出CPSP核心预测特征10项,其中疼痛灾难化量表(pain catastrophizing scale,PCS)、术前手术部位疼痛、并发症为三大核心驱动因素(累计贡献48.21%)。朴素贝叶斯(AUC=0.914)、逻辑回归(AUC=0.913)模型表现出较好的模型效果,朴素贝叶斯特异度达0.958,逻辑回归综合性能更均衡(F1分数=0.685)。SHAP分析明确了各特征对于预测结果的影响作用方向及强度,揭示PCS评分超过30分时,CPSP风险显著升高的阈值效应。结论利用解释性强的可解释机器学习算法所构建的后路腰椎椎体间融合术后CPSP风险预测模型,具有良好的判别效能和临床可解释性,且核心预测因子有助于指导临床个性化防控策略的开展,推动脊柱外科从“经验医学”向“数据驱动精准预防”转变。
摘要Discrete curves are composed of a set of ordered discrete points distributed at the intersection of the scanning plane and the surface of the object. In order to accurately calculate the geometric characteristics of any point on the discrete curve, a distance-based Gaussian weighted algorithm is proposed to estimate the geometric characteristics of three-dimensional space discrete curves. According to the definition of discrete derivatives, the algorithm fully considers the relative position difference between a specific point and its neighboring points, introduces the distance weighting idea, and integrates the smoothing strategy. The experiment uses two spatial discrete curves for uniform and non-uniform sampling, and compares them with two commonly used estimation algorithms. The comparative analysis is carried out in terms of sampling density, neighborhood radius and noise resistance. The experimental results show that the Gaussian distance weighted algorithm is effective and provides an efficient algorithm for underground pipeline safety detection.
摘要随着大语言模型(Large Language Model,LLM)技术的快速发展,高校图书馆分类编目面临智能化升级需求。为解决传统分类编目流程中效率偏低、标准适配滞后、复杂文献处理困难等问题,文章聚焦Transformer核心算法、预训练-微调算法、检索增强生成算法、人机协同反馈算法等主流算法,从分类、编目著录、数据校验与入库、后续维护等方面分析各算法的优势、劣势及效率表现。通过多维度测评发现,检索增强生成(Retrieval-Augmented Generation,RAG)算法凭借规则适配性强、知识更新高效的特点,适配综合性大学、专门学院及中等规模高校图书馆需求;人机协同反馈(Human-in-the-Loop,HITL)算法以极致准确率与风险可控性,成为研究型高校及馆藏珍贵文献图书馆的最优选择。文章构建的算法适配框架与选型建议,为高校图书馆分类编目智能化转型提供理论参考与实践指导,助力提升编目质量与资源利用效率。