Hyperparameter tuning is a key step in developing high-performing machine learning models, but searching large hyperparameter spaces requires extensive computation using standard sequential methods. This work analyzes...Hyperparameter tuning is a key step in developing high-performing machine learning models, but searching large hyperparameter spaces requires extensive computation using standard sequential methods. This work analyzes the performance gains from parallel versus sequential hyperparameter optimization. Using scikit-learn’s Randomized SearchCV, this project tuned a Random Forest classifier for fake news detection via randomized grid search. Setting n_jobs to -1 enabled full parallelization across CPU cores. Results show the parallel implementation achieved over 5× faster CPU times and 3× faster total run times compared to sequential tuning. However, test accuracy slightly dropped from 99.26% sequentially to 99.15% with parallelism, indicating a trade-off between evaluation efficiency and model performance. Still, the significant computational gains allow more extensive hyperparameter exploration within reasonable timeframes, outweighing the small accuracy decrease. Further analysis could better quantify this trade-off across different models, tuning techniques, tasks, and hardware.展开更多
及时获取并应用安全漏洞修复补丁对保障服务器用户的安全至关重要.但是,学者和机构研究发现开源软件维护者经常悄无声息地修复安全漏洞,比如维护者88%的情况在发布软件新版本时才在发行说明中告知用户修复了安全漏洞,并且只有9%的漏洞...及时获取并应用安全漏洞修复补丁对保障服务器用户的安全至关重要.但是,学者和机构研究发现开源软件维护者经常悄无声息地修复安全漏洞,比如维护者88%的情况在发布软件新版本时才在发行说明中告知用户修复了安全漏洞,并且只有9%的漏洞修复补丁明确给出对应的CVE(common vulnerabilities and exposures)标号,只有3%的修复会及时主动通知安全监控服务提供者.这导致在很多情况下,安全工程师不能通过补丁的代码和描述信息直接区分漏洞修复、Bug修复、功能性补丁.造成漏洞修复补丁不能被用户及时识别和应用,同时用户从大量的补丁提交中识别漏洞修复补丁代价很高.以代表性Linux内核为例,给出一种自动识别漏洞修复补丁的方法,该方法为补丁的代码和描述部分分别定义特征,构建机器学习模型,训练学习可区分安全漏洞补丁的分类器.实验表明,该方法可以取得91.3%的精确率、92%的准确率、87.53%的召回率,并将误报率降低到5.2%,性能提升明显.展开更多
老年人因年龄增长、身体机能衰退和认知功能减弱而面临不同程度的生活危险。因此,为了及时发现、监测和处理老年人的危险姿势,从而保护老年人的安全和健康。研究提出一种融合端对端思想和卷积神经网络(Port to port convo-lutional neur...老年人因年龄增长、身体机能衰退和认知功能减弱而面临不同程度的生活危险。因此,为了及时发现、监测和处理老年人的危险姿势,从而保护老年人的安全和健康。研究提出一种融合端对端思想和卷积神经网络(Port to port convo-lutional neural network,PTP-CNN)的老年人危险位姿虚拟模型识别算法,从而做出预防性措施或及时的护理。研究结果表明,该系统在运用PTP-CNN算法时,Epochs的训练次数为15~30之间,MSE评价指标上PTP-CNN模型分别比SW-CNN、AlexNet降低25.33%、5.17%,说明PTP-CNN模型拥有更高的准确性和精确性,可以更好地进行图像识别任务,从而及时发现老年人的危险姿势。展开更多
文摘Hyperparameter tuning is a key step in developing high-performing machine learning models, but searching large hyperparameter spaces requires extensive computation using standard sequential methods. This work analyzes the performance gains from parallel versus sequential hyperparameter optimization. Using scikit-learn’s Randomized SearchCV, this project tuned a Random Forest classifier for fake news detection via randomized grid search. Setting n_jobs to -1 enabled full parallelization across CPU cores. Results show the parallel implementation achieved over 5× faster CPU times and 3× faster total run times compared to sequential tuning. However, test accuracy slightly dropped from 99.26% sequentially to 99.15% with parallelism, indicating a trade-off between evaluation efficiency and model performance. Still, the significant computational gains allow more extensive hyperparameter exploration within reasonable timeframes, outweighing the small accuracy decrease. Further analysis could better quantify this trade-off across different models, tuning techniques, tasks, and hardware.
文摘及时获取并应用安全漏洞修复补丁对保障服务器用户的安全至关重要.但是,学者和机构研究发现开源软件维护者经常悄无声息地修复安全漏洞,比如维护者88%的情况在发布软件新版本时才在发行说明中告知用户修复了安全漏洞,并且只有9%的漏洞修复补丁明确给出对应的CVE(common vulnerabilities and exposures)标号,只有3%的修复会及时主动通知安全监控服务提供者.这导致在很多情况下,安全工程师不能通过补丁的代码和描述信息直接区分漏洞修复、Bug修复、功能性补丁.造成漏洞修复补丁不能被用户及时识别和应用,同时用户从大量的补丁提交中识别漏洞修复补丁代价很高.以代表性Linux内核为例,给出一种自动识别漏洞修复补丁的方法,该方法为补丁的代码和描述部分分别定义特征,构建机器学习模型,训练学习可区分安全漏洞补丁的分类器.实验表明,该方法可以取得91.3%的精确率、92%的准确率、87.53%的召回率,并将误报率降低到5.2%,性能提升明显.
文摘老年人因年龄增长、身体机能衰退和认知功能减弱而面临不同程度的生活危险。因此,为了及时发现、监测和处理老年人的危险姿势,从而保护老年人的安全和健康。研究提出一种融合端对端思想和卷积神经网络(Port to port convo-lutional neural network,PTP-CNN)的老年人危险位姿虚拟模型识别算法,从而做出预防性措施或及时的护理。研究结果表明,该系统在运用PTP-CNN算法时,Epochs的训练次数为15~30之间,MSE评价指标上PTP-CNN模型分别比SW-CNN、AlexNet降低25.33%、5.17%,说明PTP-CNN模型拥有更高的准确性和精确性,可以更好地进行图像识别任务,从而及时发现老年人的危险姿势。
