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Cross-Project Software Defect Prediction Based on SMOTE and Deep Canonical Correlation Analysis
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作者 Xin Fan Shuqing Zhang +2 位作者 Kaisheng Wu Wei Zheng Yu Ge 《Computers, Materials & Continua》 SCIE EI 2024年第2期1687-1711,共25页
Cross-Project Defect Prediction(CPDP)is a method that utilizes historical data from other source projects to train predictive models for defect prediction in the target project.However,existing CPDP methods only consi... Cross-Project Defect Prediction(CPDP)is a method that utilizes historical data from other source projects to train predictive models for defect prediction in the target project.However,existing CPDP methods only consider linear correlations between features(indicators)of the source and target projects.These models are not capable of evaluating non-linear correlations between features when they exist,for example,when there are differences in data distributions between the source and target projects.As a result,the performance of such CPDP models is compromised.In this paper,this paper proposes a novel CPDP method based on Synthetic Minority Oversampling Technique(SMOTE)and Deep Canonical Correlation Analysis(DCCA),referred to as S-DCCA.Canonical Correlation Analysis(CCA)is employed to address the issue of non-linear correlations between features of the source and target projects.S-DCCA extends CCA by incorporating the MlpNet model for feature extraction from the dataset.The redundant features are then eliminated by maximizing the correlated feature subset using the CCA loss function.Finally,cross-project defect prediction is achieved through the application of the SMOTE data sampling technique.Area Under Curve(AUC)and F1 scores(F1)are used as evaluation metrics.This paper conducted experiments on 27 projects from four public datasets to validate the proposed method.The results demonstrate that,on average,our method outperforms all baseline approaches by at least 1.2%in AUC and 5.5%in F1 score.This indicates that the proposed method exhibits favorable performance characteristics. 展开更多
关键词 cross-project defect prediction deep canonical correlation analysis feature similarity
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Within-Project and Cross-Project Software Defect Prediction Based on Improved Transfer Naive Bayes Algorithm 被引量:3
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作者 Kun Zhu Nana Zhang +1 位作者 Shi Ying Xu Wang 《Computers, Materials & Continua》 SCIE EI 2020年第5期891-910,共20页
With the continuous expansion of software scale,software update and maintenance have become more and more important.However,frequent software code updates will make the software more likely to introduce new defects.So... With the continuous expansion of software scale,software update and maintenance have become more and more important.However,frequent software code updates will make the software more likely to introduce new defects.So how to predict the defects quickly and accurately on the software change has become an important problem for software developers.Current defect prediction methods often cannot reflect the feature information of the defect comprehensively,and the detection effect is not ideal enough.Therefore,we propose a novel defect prediction model named ITNB(Improved Transfer Naive Bayes)based on improved transfer Naive Bayesian algorithm in this paper,which mainly considers the following two aspects:(1)Considering that the edge data of the test set may affect the similarity calculation and final prediction result,we remove the edge data of the test set when calculating the data similarity between the training set and the test set;(2)Considering that each feature dimension has different effects on defect prediction,we construct the calculation formula of training data weight based on feature dimension weight and data gravity,and then calculate the prior probability and the conditional probability of training data from the weight information,so as to construct the weighted bayesian classifier for software defect prediction.To evaluate the performance of the ITNB model,we use six datasets from large open source projects,namely Bugzilla,Columba,Mozilla,JDT,Platform and PostgreSQL.We compare the ITNB model with the transfer Naive Bayesian(TNB)model.The experimental results show that our ITNB model can achieve better results than the TNB model in terms of accurary,precision and pd for within-project and cross-project defect prediction. 展开更多
关键词 cross-project defect prediction transfer Naive Bayesian algorithm edge data similarity calculation feature dimension weight
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Graph-Based Feature Learning for Cross-Project Software Defect Prediction 被引量:1
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作者 Ahmed Abdu Zhengjun Zhai +2 位作者 Hakim A.Abdo Redhwan Algabri Sungon Lee 《Computers, Materials & Continua》 SCIE EI 2023年第10期161-180,共20页
Cross-project software defect prediction(CPDP)aims to enhance defect prediction in target projects with limited or no historical data by leveraging information from related source projects.The existing CPDP approaches... Cross-project software defect prediction(CPDP)aims to enhance defect prediction in target projects with limited or no historical data by leveraging information from related source projects.The existing CPDP approaches rely on static metrics or dynamic syntactic features,which have shown limited effectiveness in CPDP due to their inability to capture higher-level system properties,such as complex design patterns,relationships between multiple functions,and dependencies in different software projects,that are important for CPDP.This paper introduces a novel approach,a graph-based feature learning model for CPDP(GB-CPDP),that utilizes NetworkX to extract features and learn representations of program entities from control flow graphs(CFGs)and data dependency graphs(DDGs).These graphs capture the structural and data dependencies within the source code.The proposed approach employs Node2Vec to transform CFGs and DDGs into numerical vectors and leverages Long Short-Term Memory(LSTM)networks to learn predictive models.The process involves graph construction,feature learning through graph embedding and LSTM,and defect prediction.Experimental evaluation using nine open-source Java projects from the PROMISE dataset demonstrates that GB-CPDP outperforms state-of-the-art CPDP methods in terms of F1-measure and Area Under the Curve(AUC).The results showcase the effectiveness of GB-CPDP in improving the performance of cross-project defect prediction. 展开更多
关键词 cross-project defect prediction graphs features deep learning graph embedding
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Unsupervised Domain Adaptation Based on Discriminative Subspace Learning for Cross-Project Defect Prediction 被引量:1
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作者 Ying Sun Yanfei Sun +4 位作者 Jin Qi Fei Wu Xiao-Yuan Jing Yu Xue Zixin Shen 《Computers, Materials & Continua》 SCIE EI 2021年第9期3373-3389,共17页
:Cross-project defect prediction(CPDP)aims to predict the defects on target project by using a prediction model built on source projects.The main problem in CPDP is the huge distribution gap between the source project... :Cross-project defect prediction(CPDP)aims to predict the defects on target project by using a prediction model built on source projects.The main problem in CPDP is the huge distribution gap between the source project and the target project,which prevents the prediction model from performing well.Most existing methods overlook the class discrimination of the learned features.Seeking an effective transferable model from the source project to the target project for CPDP is challenging.In this paper,we propose an unsupervised domain adaptation based on the discriminative subspace learning(DSL)approach for CPDP.DSL treats the data from two projects as being from two domains and maps the data into a common feature space.It employs crossdomain alignment with discriminative information from different projects to reduce the distribution difference of the data between different projects and incorporates the class discriminative information.Specifically,DSL first utilizes subspace learning based domain adaptation to reduce the distribution gap of data between different projects.Then,it makes full use of the class label information of the source project and transfers the discrimination ability of the source project to the target project in the common space.Comprehensive experiments on five projects verify that DSL can build an effective prediction model and improve the performance over the related competing methods by at least 7.10%and 11.08%in terms of G-measure and AUC. 展开更多
关键词 cross-project defect prediction discriminative subspace learning unsupervised domain adaptation
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渤海海峡跨海通道工程南段地应力特征与工程稳定性分析 被引量:1
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作者 乔二伟 马秀敏 +2 位作者 郭华林 孙尧 姜景捷 《地质力学学报》 北大核心 2025年第2期197-210,共14页
渤海海峡跨海通道工程是连接山东半岛与辽东半岛重要的海上交通主线工程,沿线地应力状态是工程设计和施工决策的重要参考依据。为了准确获得工程南段地区现今地应力特征及构造应力场分布特征,在烟台市蓬莱区西南北沟镇实施了300m以浅的... 渤海海峡跨海通道工程是连接山东半岛与辽东半岛重要的海上交通主线工程,沿线地应力状态是工程设计和施工决策的重要参考依据。为了准确获得工程南段地区现今地应力特征及构造应力场分布特征,在烟台市蓬莱区西南北沟镇实施了300m以浅的水压致裂法地应力测量。结果表明:测区主导应力为水平构造应力,与东北—华北应力区其他地区相比,应力值处于中等;随测量深度增加,最大水平主应力(S_(H))、最小水平主应力(S_(h))和垂向主应力(S_(v))均呈线性增大趋势;在测量深度范围内地壳浅表层应力结构以逆断型为主,即S_(H)>S_(h)>S_(v);实测S_(H)平均方位角为N75.3°E,与华北应力区的应力场方向一致,也与其震源机制解和GPS测量揭示的区域构造应力场方向基本一致。应用库仑摩擦滑动准则和此次测量数据,初步评估了渤海海峡跨海通道工程南段地区现今地应力积累水平及其对工程稳定性的影响,认为σ_(θ_(max))区域内应力积累总体水平相对较低,工程区域地壳相对稳定。依据岩爆危险程度综合判别准则/R_(c)讨论了通道区域地下隧道工程围岩岩爆的可能性,认为该工程地下隧道发生岩爆可能性很低,隧道围岩总体稳定。研究结果为渤海海峡跨海通道工程的设计、施工等方案的优选提供了科学依据,同时也可为区域活动断裂、地震地质、区域动力学等研究提供基础数据。 展开更多
关键词 渤海海峡 跨海通道工程 水压致裂法 地应力 围岩稳定性 构造应力场
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融合静态分析警告的软件缺陷预测模型及其应用研究
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作者 吴海涛 马景悦 高建华 《计算机科学与探索》 北大核心 2025年第3期818-834,共17页
静态分析警告作为一种重要的软件质量指标,被广泛用于识别源代码中潜在的违规问题。近期的研究表明,静态分析警告在代码异味检测和即时缺陷预测中有所应用,但有关项目早期缺少提交修改记录的情况没有涉及。针对上述问题,利用三种流行的... 静态分析警告作为一种重要的软件质量指标,被广泛用于识别源代码中潜在的违规问题。近期的研究表明,静态分析警告在代码异味检测和即时缺陷预测中有所应用,但有关项目早期缺少提交修改记录的情况没有涉及。针对上述问题,利用三种流行的静态分析工具的警告信息,在原有的缺陷预测模型中融合静态分析警告这个新的度量,构建一个涵盖软件开发和代码可维护性的缺陷预测模型,并探究静态分析警告与缺陷的潜在关系,融合警告对软件缺陷预测模型性能的影响以及在跨项目场景中的影响。实验结果表明,警告数量往往与缺陷分布密切相关,呈现正相关的关系,即警告这一度量在软件缺陷预测模型中有相当大的潜力,并且在有缺陷数据中报告的警告信息往往与编码规范相关;融合警告之后,缺陷预测模型在各项目上的平均精度提高1.4%~14.7%,平均召回率提高0.2%~2.4%,平均F1提高0.3%~3.0%,平均AUC提高0.2%~1.4%。在跨项目场景中,CODE+SAW_VIF度量提供了最佳性能的缺陷预测模型,融合静态分析警告能够提升模型识别缺陷的性能。 展开更多
关键词 软件缺陷 静态分析工具 静态分析警告 代码度量 跨项目场景预测
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长江盾构穿越工程用厚壁大直径18 m UOE焊管的开发
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作者 谢仕强 侯杰廷 +1 位作者 章传国 钟桂香 《钢管》 2025年第1期26-32,共7页
介绍了长江盾构穿越工程的情况和主要技术要求,重点介绍了宝钢股份采用一贯制制造技术为长江盾构穿越工程开发的X80钢级φ1422 mm×32.1 mm UOE 18 m加长直缝埋弧焊接钢管的性能特点。分析结果表明,该钢管具有超低的C含量、较高的Mn... 介绍了长江盾构穿越工程的情况和主要技术要求,重点介绍了宝钢股份采用一贯制制造技术为长江盾构穿越工程开发的X80钢级φ1422 mm×32.1 mm UOE 18 m加长直缝埋弧焊接钢管的性能特点。分析结果表明,该钢管具有超低的C含量、较高的Mn和Nb含量,显微组织细小,具有较高的强度、韧性及良好的焊接性,满足项目要求。该加长钢管的成功开发和应用,填补了国内外穿江隧道工程用特厚、特长X80钢级大直径UOE直缝埋弧焊接钢管的空白。 展开更多
关键词 直缝埋弧焊钢管 X80钢级 UOE 加长管 长江盾构穿越工程
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三维潮流模型在营口LNG码头取排水工程中的应用
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作者 何军 武政 《水运工程》 2025年第7期93-104,157,共13页
鉴于液化天然气(LNG)码头在运营过程中需要消耗大量海水作为冷源,取排水工程的建设显得尤为重要。取排水活动不可避免地对工程邻近水域的流场产生影响,因此,对工程附近潮流场进行系统分析是十分必要的。以营口LNG码头工程为例,利用开源... 鉴于液化天然气(LNG)码头在运营过程中需要消耗大量海水作为冷源,取排水工程的建设显得尤为重要。取排水活动不可避免地对工程邻近水域的流场产生影响,因此,对工程附近潮流场进行系统分析是十分必要的。以营口LNG码头工程为例,利用开源水动力数值模型FVCOM,模拟并对比分析营口LNG码头取排水工程实施前后港区内的潮流场水动力特性,重点探讨了取排水口建设对附近三维流场的影响。模拟结果表明:工程实施后取排水口附近潮流场的表层及底层流速幅值均有轻微变化,但表层最大流速变化量不超过0.05 m/s。通过对港区内典型测点处的表层横流流速进行分析,发现各特征点位的横流流速差最大不超过0.016 m/s。综上,取排水工程的实施对研究区域内潮流场水动力特性的影响范围十分有限,特别对整体潮流场的分布规律未产生显著改变。研究成果可为同类型港口工程的设计与评估提供参考。 展开更多
关键词 LNG码头 取排水工程 水动力特性 横流
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墙背高填式省水船闸刚性桩复合地基处理研究 被引量:1
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作者 戈国庆 张毅濠 +2 位作者 王曙光 何良德 孟彦廷 《人民长江》 北大核心 2025年第6期130-137,161,共9页
省水船闸在中国北方平原地区应用潜力较大,但在软土覆盖层深厚的鲁西平原等地区,多级分布式省水船闸闸室结构本身和墙背高填土将引起地基显著沉降,不利于工程安全。以“位山-解山”渡槽穿黄-八级分散式省水船闸为例,考虑厚覆盖层、高水... 省水船闸在中国北方平原地区应用潜力较大,但在软土覆盖层深厚的鲁西平原等地区,多级分布式省水船闸闸室结构本身和墙背高填土将引起地基显著沉降,不利于工程安全。以“位山-解山”渡槽穿黄-八级分散式省水船闸为例,考虑厚覆盖层、高水头、墙背高填土等复杂条件,结合宽缝施工,提出了多种填土区与闸底刚性桩布置及桩顶连接方案,并建立有限元模型分析了闸室与桩体的受力、变形特性。结果表明:填土区宜采用等桩长变间距带桩帽布置,闸底宜采用边密中疏布置,宽缝宜在第③~⑤级省水池挡墙及回填土施工时封合;闸墙与桩顶刚接使得底板与闸墙差异沉降最小,可作为最优的桩顶连接方式,但此时桩身弯矩、剪力均超过预应力管桩极限承载力,需将其替换为灌注桩作为优化的刚性桩组合地基处理方案;优化方案下,闸墙外侧桩体顶部轴力、剪力及弯矩均最大,但仍在灌注桩极限承载力范围内。 展开更多
关键词 省水船闸 复合地基 地基处理 刚性连接 宽缝施工 京杭运河 穿黄工程
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A Cluster Based Feature Selection Method for Cross-Project Software Defect Prediction 被引量:7
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作者 Chao Ni Wang-Shu Liu +3 位作者 Xiang Chen Qing Gu Dao-Xu Chen Qi-Guo Huang 《Journal of Computer Science & Technology》 SCIE EI CSCD 2017年第6期1090-1107,共18页
Cross-project defect prediction (CPDP) uses the labeled data from external source software projects to com- pensate the shortage of useful data in the target project, in order to build a meaningful classification mo... Cross-project defect prediction (CPDP) uses the labeled data from external source software projects to com- pensate the shortage of useful data in the target project, in order to build a meaningful classification model. However, the distribution gap between software features extracted from the source and the target projects may be too large to make the mixed data useful for training. In this paper, we propose a cluster-based novel method FeSCH (Feature Selection Using Clusters of Hybrid-Data) to alleviate the distribution differences by feature selection. FeSCH includes two phases. Tile feature clustering phase clusters features using a density-based clustering method, and the feature selection phase selects features from each cluster using a ranking strategy. For CPDP, we design three different heuristic ranking strategies in the second phase. To investigate the prediction performance of FeSCH, we design experiments based on real-world software projects, and study the effects of design options in FeSCH (such as ranking strategy, feature selection ratio, and classifiers). The experimental results prove the effectiveness of FeSCH. Firstly, compared with the state-of-the-art baseline methods, FeSCH achieves better performance and its performance is less affected by the classifiers used. Secondly, FeSCH enhances the performance by effectively selecting features across feature categories, and provides guidelines for selecting useful features for defect prediction. 展开更多
关键词 software defect prediction cross-project defect prediction feature selection feature clustering density-basedclustering
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时序因素对即时软件缺陷预测性能影响的实证研究
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作者 张雨 于巧 +2 位作者 祝义 姜淑娟 张淑涛 《计算机工程与应用》 北大核心 2025年第14期362-376,共15页
即时软件缺陷预测是针对开发者提交的代码变更是否存在缺陷进行预测。近年来,由于其细粒度、即时性、易追溯的特点,即时软件缺陷预测成为了缺陷预测领域的研究热点。代码变更提交具有时间特性,然而,现有研究大多忽略了时序因素对即时软... 即时软件缺陷预测是针对开发者提交的代码变更是否存在缺陷进行预测。近年来,由于其细粒度、即时性、易追溯的特点,即时软件缺陷预测成为了缺陷预测领域的研究热点。代码变更提交具有时间特性,然而,现有研究大多忽略了时序因素对即时软件缺陷预测的影响。因此,探究代码变更提交时间对即时软件缺陷预测性能的影响规律具有重要意义。探究了时序因素对项目内和跨项目即时软件缺陷预测性能的影响,采用随机森林、CNN和XGBoost三种模型在9个即时软件缺陷预测数据集上展开了实证研究。研究结果表明:在项目内缺陷预测中,训练集与测试集时间越接近,模型性能越好;与非时序场景相比,时序场景下的跨项目缺陷预测与项目内缺陷预测的性能差距更小。因此,在即时软件缺陷预测研究中应该充分考虑时序因素的影响,在进行训练集的选择时应优先考虑与测试集时间相距较近的数据集。 展开更多
关键词 即时软件缺陷预测(JIT-SDP) 时序因素 跨项目缺陷预测
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A Novel Cross-Project Software Defect Prediction Algorithm Based on Transfer Learning 被引量:5
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作者 Shiqi Tang Song Huang +3 位作者 Changyou Zheng Erhu Liu Cheng Zong Yixian Ding 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2022年第1期41-57,共17页
Software Defect Prediction(SDP) technology is an effective tool for improving software system quality that has attracted much attention in recent years.However,the prediction of cross-project data remains a challenge ... Software Defect Prediction(SDP) technology is an effective tool for improving software system quality that has attracted much attention in recent years.However,the prediction of cross-project data remains a challenge for the traditional SDP method due to the different distributions of the training and testing datasets.Another major difficulty is the class imbalance issue that must be addressed in Cross-Project Defect Prediction(CPDP).In this work,we propose a transfer-leaning algorithm(TSboostDF) that considers both knowledge transfer and class imbalance for CPDP.The experimental results demonstrate that the performance achieved by TSboostDF is better than those of existing CPDP methods. 展开更多
关键词 Software Defect Prediction(SDP) transfer learning imbalance class cross-project
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Combined classifier for cross-project defect prediction: an extended empirical study 被引量:2
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作者 Yun ZHANG David LO +1 位作者 Xin XIA Jianling SUN 《Frontiers of Computer Science》 SCIE EI CSCD 2018年第2期280-296,共17页
To facilitate developers in effective allocation of their testing and debugging efforts, many software defect prediction techniques have been proposed in the literature. These techniques can be used to predict classes... To facilitate developers in effective allocation of their testing and debugging efforts, many software defect prediction techniques have been proposed in the literature. These techniques can be used to predict classes that are more likely to be buggy based on the past history of classes, methods, or certain other code elements. These techniques are effective provided that a sufficient amount of data is available to train a prediction model. However, sufficient training data are rarely available for new software projects. To resolve this problem, cross-project defect prediction, which transfers a prediction model trained using data from one project to another, was proposed and is regarded as a new challenge in the area of defect prediction. Thus far, only a few cross-project defect prediction techniques have been proposed. To advance the state of the art, in this study, we investigated seven composite algorithms that integrate multiple machine learning classifiers to improve cross-project defect prediction. To evaluate the performance of the composite algorithms, we performed experiments on 10 open-source software systems from the PROMISE repository, which contain a total of 5,305 instances labeled as defective or clean. We compared the composite algorithms with the combined defect predictor where logistic regression is used as the meta classification algorithm (CODEPLogistic), which is the most recent cross-project defect prediction algorithm in terms of two standard evaluation metrics: cost effectiveness and F-measure. Our experimental results show that several algorithms outperform CODEPLogistic:Maximum voting shows the best performance in terms of F-measure and its average F-measure is superior to that of CODEPLogistic by 36.88%. Bootstrap aggregation (Bagging J48) shows the best performance in terms of cost effectiveness and its average cost effectiveness is superior to that of CODEPLogistic by 15.34%. 展开更多
关键词 defect prediction cross-project classifier combination
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Effort-aware cross-project just-in-time defect prediction framework for mobile apps 被引量:1
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作者 Tian CHENG Kunsong ZHAO +2 位作者 Song SUN Muhammad MATEEN Junhao WEN 《Frontiers of Computer Science》 SCIE EI CSCD 2022年第6期15-29,共15页
As the boom of mobile devices,Android mobile apps play an irreplaceable roles in people’s daily life,which have the characteristics of frequent updates involving in many code commits to meet new requirements.Just-in-... As the boom of mobile devices,Android mobile apps play an irreplaceable roles in people’s daily life,which have the characteristics of frequent updates involving in many code commits to meet new requirements.Just-in-Time(JIT)defect prediction aims to identify whether the commit instances will bring defects into the new release of apps and provides immediate feedback to developers,which is more suitable to mobile apps.As the within-app defect prediction needs sufficient historical data to label the commit instances,which is inadequate in practice,one alternative method is to use the cross-project model.In this work,we propose a novel method,called KAL,for cross-project JIT defect prediction task in the context of Android mobile apps.More specifically,KAL first transforms the commit instances into a high-dimensional feature space using kernel-based principal component analysis technique to obtain the representative features.Then,the adversarial learning technique is used to extract the common feature embedding for the model building.We conduct experiments on 14 Android mobile apps and employ four effort-aware indicators for performance evaluation.The results on 182 cross-project pairs demonstrate that our proposed KAL method obtains better performance than 20 comparative methods. 展开更多
关键词 kernel-based principal component analysis adversarial learning just-in-time defect prediction cross-project model
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横流超限情况下桥下净空宽度校核方法探讨
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作者 许光祥 陈沁芷 +2 位作者 李帆 周千凯 王多银 《重庆交通大学学报(自然科学版)》 北大核心 2025年第5期1-7,共7页
横流超过0.8 m/s限制的跨通航河流大桥净空宽度,内河通航标准只有定性的规定,没有给出确切的校核方法。以桃源二线船闸工程中的重建沅水大桥右汊通航孔为例,对横流超限桥梁净空宽度校核方法进行了探索。提出横流超限后,可以采用航道宽... 横流超过0.8 m/s限制的跨通航河流大桥净空宽度,内河通航标准只有定性的规定,没有给出确切的校核方法。以桃源二线船闸工程中的重建沅水大桥右汊通航孔为例,对横流超限桥梁净空宽度校核方法进行了探索。提出横流超限后,可以采用航道宽度校核、桥轴线旋转使横流不超限后的投影净宽校核、通航孔是否一孔跨过通航水域校核等三重校核的方式进行论证。应用1∶100正态河工模型测试的桥区试验资料,采用数值矢量图的方式展现流向、横流的分布及其不利测点,对重建桃源沅水大桥右汊通航孔进行了净空宽度论证和校核,结果表明三重校核方式较适合于横流超限情况。 展开更多
关键词 桥梁工程 横流超限 净空宽度 数值矢量图 投影净宽
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圆锥台共形阵半空间扫描波束极化综合与分析
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作者 吕强 魏宇飞 +1 位作者 陈曦 刘皓鹏 《现代防御技术》 北大核心 2025年第3期139-149,共11页
共形阵天线受载体曲率影响,各阵元的方向图和极化方向均不相同,造成共形阵天线在大角度波束综合时存在波束综合效率低、高交叉极化电平难以抑制等问题。目前大多采用差分进化等算法进行共形阵全局优化,阵列综合的过程复杂、效率低。基... 共形阵天线受载体曲率影响,各阵元的方向图和极化方向均不相同,造成共形阵天线在大角度波束综合时存在波束综合效率低、高交叉极化电平难以抑制等问题。目前大多采用差分进化等算法进行共形阵全局优化,阵列综合的过程复杂、效率低。基于一种圆锥台结构的共形阵天线布局,采用以投影规则为依据的波束极化综合算法,实现了对共形阵的大角度波束扫描和高极化纯度的高效综合。计算结果表明,提出的解析算法能够实现共形阵天线在半空域内的高性能波束扫描,在主波束内始终保持良好的低交叉极化特性。最后采用基于全波数值方法的高频仿真软件验证了所提出算法的准确性和有效性。该方法可为高性能共形阵的工程实现提供理论基础。 展开更多
关键词 共形阵 交叉极化 方向图综合 投影规则 宽角扫描
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基于知识边界跨越视角的跨职能项目知识整合机制研究
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作者 林琳 于米 鲍晓娜 《科技管理研究》 2025年第11期178-189,共12页
在跨职能项目中,如何有效集成不同专业领域的知识,并与项目管理的知识相衔接和融合,以提升项目绩效,已成为众多中国企业进行项目管理实践面临的核心问题。基于边界跨越视角,深入剖析了跨职能项目的知识整合过程,并以大型国有企业DXS为案... 在跨职能项目中,如何有效集成不同专业领域的知识,并与项目管理的知识相衔接和融合,以提升项目绩效,已成为众多中国企业进行项目管理实践面临的核心问题。基于边界跨越视角,深入剖析了跨职能项目的知识整合过程,并以大型国有企业DXS为案例,进行探索性案例研究,通过将项目全生命周期划分为启动、计划、执行和收尾4个阶段,分别识别了各阶段中语法、语义和语用3种知识边界的边界跨越者和跨越载体,挖掘显性、隐性知识的整合过程和整合机制,分析跨职能项目知识整合的内在机理。研究结果表明:项目中标准化表格及工具等知识边界跨越载体,促进编码化的显性知识整合;项目经理、专业负责人等知识边界跨越者,促进复杂显性和隐性知识的整合;知识边界跨越者和跨越载体联合,促进不易表达的隐性知识的整合。研究结论建立起跨职能项目情境下知识边界跨越与知识整合之间的内在联系,拓展了现有理论,为跨职能项目的管理提供有针对性的指导。 展开更多
关键词 跨职能项目 知识边界 知识整合 案例研究 边界跨越者 跨越载体
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不同拟合指标下模拟节理岩体结构面产状的Copula函数方法
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作者 任青阳 施俭 +1 位作者 王彦丁 肖宋强 《科学技术与工程》 北大核心 2025年第10期4274-4283,共10页
为准确选取模拟节理岩体结构面产状互相关性的Copula函数,提出了不同拟合指标下模拟节理岩体结构面产状的Copula函数方法,通过采用最小平方欧式、AIC(Akaike information criterion)信息准则、BIC(Bayesian information criterion)信息... 为准确选取模拟节理岩体结构面产状互相关性的Copula函数,提出了不同拟合指标下模拟节理岩体结构面产状的Copula函数方法,通过采用最小平方欧式、AIC(Akaike information criterion)信息准则、BIC(Bayesian information criterion)信息准则这3种拟合指标确定各自的最优Copula函数并通过MATLAB确定实测产状数据的最优边缘分布,建立倾角和倾向的二维联合分布函数。同时结合蒙特卡洛抽样法自动生成模拟数据,将数据导入Dips软件中进行可视化处理,得到产状的赤平投影图,对比实测的倾角和倾向数据和不同拟合指标下确定的Copula函数模拟数据间的差异。最后,基于工程案例检验方法的有效性。结果表明:不同的拟合指标会产生不同的Copula函数,对模拟产状的有效性也会有较大差异,若是选择不当的拟合指标可能导致选择不准确的Copula函数,从而使模型无法准确地捕捉数据的相关结构和特征;不适当的拟合指标可能导致拟合模型与真实数据之间存在较大的误差,使得模型的预测能力和解释能力下降,就本文案例表明在最小平方欧式值拟合指标下选择的Gaussian Copula函数拟合实测数据效果最好。此研究将有助在应用Coupla函数时选用恰当的拟合指标。 展开更多
关键词 结构面 COPULA函数 产状 拟合指标 互相关性 赤平投影
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论项目式教学与混合学习模式在国际中文教育中的融合发展
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作者 郑艳群 刘冰 《华文教学与研究》 2025年第2期51-57,共7页
在全球化与数字化的推动下,语言教育面临多元化需求与技术创新应用的挑战。传统模式难以同时满足对跨文化交际能力培养的需求,以及多元、公平、包容等全球教育价值的要求,而项目式教学以任务驱动、真实情景和跨文化互动等为核心特征,能... 在全球化与数字化的推动下,语言教育面临多元化需求与技术创新应用的挑战。传统模式难以同时满足对跨文化交际能力培养的需求,以及多元、公平、包容等全球教育价值的要求,而项目式教学以任务驱动、真实情景和跨文化互动等为核心特征,能够满足语言实践与文化理解的需求;混合学习模式通过线上线下资源的灵活整合与技术支持,能够为学生提供个性化学习体验和实时反馈。两者的融合为国际中文教育带来新的发展机遇与创新方向。基于理论分析与“星谈”项目案例可见,项目式教学依托技术赋能实现了更加高效的实践;混合学习基于任务驱动展现了更丰富的资源多样性与互动优势,不仅有助于提升学生的语言技能与跨文化沟通能力,还在多学科协作与职业规划等方面更好地发挥潜能。随着虚拟现实、人工智能等技术的不断成熟,项目式教学与混合学习模式将在国际中文教育中展现更大的潜力,为构建面向全球化时代的高质量语言教学体系提供理论支撑与实践经验。 展开更多
关键词 项目式教学 混合学习 国际中文教育 跨文化交流 融合发展
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基于投影和交叉熵的Picture模糊多属性群决策方法
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作者 李亚娟 范建平 吴美琴 《科技和产业》 2025年第10期18-24,共7页
针对方案属性值为Picture模糊数(Picture fuzzy numbers, PFN)的多属性群决策(multiple attributes group decision making, MAGDM)问题,提出一种基于投影法和交叉熵的Picture模糊多属性群决策方法。将投影法引入Picture模糊多属性群决... 针对方案属性值为Picture模糊数(Picture fuzzy numbers, PFN)的多属性群决策(multiple attributes group decision making, MAGDM)问题,提出一种基于投影法和交叉熵的Picture模糊多属性群决策方法。将投影法引入Picture模糊多属性群决策中求出专家的权重,利用交叉熵求出各专家对应的各方案与理想方案的加权对称差异信息测度值,然后根据专家权重对其进行集结求出各方案与理想方案的加权对称差异信息测度值进而排序得出最优方案。最后通过企业资源计划(ERP)系统的选择表明该方法的可行性和有效性。 展开更多
关键词 Picture模糊集 多属性群决策 投影法 交叉熵
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