Anomaly detection in dynamic graphs aims to capture the dynamic evolution characteristics of graphs, and then identify abnormal behaviors that deviate from normal patterns. However, previous studies fail to decouple periodic and bursty information during the time encoding process, which hinders their performances. In addition, most existing methods use attention mechanisms to capture the importance of time points. They fail to leverage the normal and abnormal characteristics in the frequency domain. To address the above issues, we propose a model that integrates multi-scale Frequency encoding with Time-frequency Attention for Anomaly Detection in dynamic graphs, named FreqTAD. We design a multi-scale frequency encoder that decomposes time series into distinct periodic and bursty components. Moreover, we present an effective time-frequency attention mechanism that focuses on frequency components to differentiate frequency-domain features of normal and abnormal behaviors. Experimental results on four datasets demonstrate the superior performance of FreqTAD in both anomaly detection accuracy and computational efficiency.

Graph Neural Networks (GNNs) have demonstrated impressive success across a range of graph-based tasks. However, their performance in node classification typically relies on enough high-quality labeled data which are difficult to obtain in practice. Self-training emerges as a promising solution to tackle the issue of label scarcity. Most existing studies in this direction mainly rely on classification scores to explore high-confidence unlabeled samples. Nevertheless, these methods often lead to false positive samples, which hinders the capability of GNNs. To this end, we propose a simple yet effective Topology-Aware Graph Self-Training (TA-GST) method. Specifically, we first explore the origin of false positives in pseudo-labeled samples. We then design a topology-aware scoring method, which considers both the classification score and connectivity pattern to enhance the reliability of pseudo-labeled samples. Besides, we depart TA-GST from the traditional teacher-student pattern and simplify it in an end-to-end manner. Extensive experiments on seven real-world datasets demonstrate the effectiveness of our method.

Graph Structure Learning (GSL) aims to simultaneously enhance the original graph and the performance of Graph Neural Networks. However, existing GSL methods for node classification fail to consider neighborhood label dependencies during training, which limits their ability to refine the graph structure in an adaptive manner. Furthermore, the training of those methods lacks a proper schedule based on graph structure quality, thereby yielding suboptimal performance. To address these challenges, we propose a novel GSL framework for node classification, termed DuAl hypeRgraph-enhanced curricuLum-guided graph structure learnING for node classification (DARLING). It first introduces a graph structure curriculum module to effectively discriminate the suboptimal graph structures by examining both the distribution of neighborhood labels and the degree of nodes. Subsequently, a self-supervised dual hypergraph similarity learning module is proposed to capture higher-order neighborhood label dependencies. This is achieved via formulating a pre-training task that involves hyperedge batch-filling within the dual hypergraph of the input graph. The experimental results on six datasets demonstrate that the proposed DARLING outperforms eleven state-of-the-art methods significantly, in terms of effectiveness and robustness.

Dynamic graph neural networks (DyGNNs) currently struggle with handling distribution shifts that naturally arise when training and test data follow similar but non-identical distributions. As the generation of dynamic graphs is strongly influenced by latent environments, it is critical to investigate their impacts on the generalization behavior of DyGNNs. We therefore establish a connection between the temporal message-passing scheme employed by DyGNNs and their generalization performance under distribution shifts. Our analysis reveals that environment-specific factors misguide the learning process and lead to unsatisfactory out-of-distribution (OOD) generalization. Based on this insight, we propose MoVE, a Mixture of Variational Experts network to mitigate complex distribution shifts in dynamic graphs. MoVE adopts a hierarchical variational architecture that extrapolates latent representations into a mixture of distribution shifts as pseudo-environments. Additionally, we incorporate a Mixture-of-Experts (MoE) framework with a novel training objective that aligns the outputs of different experts to produce invariant representations. Extensive experiments on various dynamic graphs, including both real-world and synthetic datasets, demonstrate that our model significantly outperforms state-of-the-art techniques.

Accurate cellular traffic prediction is crucial for the rational allocation of network resources. Existing methods generally overlook the accurate extraction and full utilization of features across different periods of cellular traffic. Thus, we propose a Relative Long Short-Term Adaptive Spatial-Temporal Targeted Extraction (RLSASTTE) network, which fully extracts long-term trends and short-term dynamics, and then maximizes their utilization. First, to extract long-term spatial-temporal features, we exploit the strength of the Transformer in capturing long-range temporal dependencies, address its limitations in spatial relationship modeling by redesigning a spatial-temporal attention mechanism, and further adopt a pre-decomposition strategy to emphasize seasonal component mining. Second, to capture short-term spatial-temporal features, we define a multi-dilation convolution to explore short-term dependencies and design a novel local strong correlation dynamic attention mechanism to investigate local spatial influences, which also eliminates the limitation of fixed neighboring nodes. Finally, we innovatively employ an adaptive dual gating mechanism to efficiently integrate diverse features. We conducted experiments on three real-world datasets. Compared to the state-of-the-art methods, RLSASTTE achieves reductions of at least 3.1% and 3.7% in mean absolute error and root mean square error, respectively. In addition, we explore auxiliary training based on data augmentation, achieving additional performance improvements of 2.0% to 4.5%.

Current crop disease VQA models primarily focus on object counting and detection. However, accurately identifying various disease stages and determining control measures re quire additional knowledge beyond images, including information about control methods and pathogen details. To address this, the VQA dataset relies on the images and questions to retrieve relevant external knowledge. To realize the VQA task of crop diseases external knowledge, we construct the Visual Question Answer Model Based on Crop Diseases External Knowledge for Smart Agriculture (CDEK). CDEK integrates two categories of external knowledge on 66 common dicotyledonous crop diseases by utilizing large language models and agricultural knowledge repositories to enhance knowledge retrieval. This integration enhances the richness of external knowledge repositories. En hancing fine-grained image understanding in CDEK through the utilization of Stack Self-Attention (SSA), utilising Cross Attention and contrastive learning of two external knowledge, with a focus on emphasizing image-related semantic information during training. Finally, an automatic patrol disease detection robot is constructed based on Tensor Processing Unit (TPU) devices and the CDEK model. CDEK achieves an accuracy of 61.7% on the publicly available dataset OK-VQA, surpassing the previous state-of-the-art by 5.1%. Furthermore, we construct the OKiCD-VQA dataset for crop diseases external knowledge and achieve an accuracy of 89.36% using CDEK. A series of ablation experiments are conducted on various modules, the effectiveness of CDEK is demonstrated through extensive experimentation. Contributing solutions to the sustainable development of smart agriculture.

Human-Object Interaction (HOI) detection remains challenging due to the semantic ambiguity of interaction categories and the limited discriminability of their feature representations. Existing approaches often improve recognition by employing sophisticated models or auxiliary textual annotations. While effective in certain gains, these solutions incur additional computational or annotation costs and struggle to capture intrinsic interaction regularities. To address these issues, we propose Pose-Guided Multi-Cue Explicit Query Construction (PM-EQC), a unified Transformer-based framework that builds upon collaborative modeling of appearance, spatial, and pose cues for discriminative interaction reasoning. At its core, the Collaborative Multi-Cue Query Constructor (CM-CQC) jointly models dependencies among visual cues to generate explicit query embeddings. CM-CQC further incorporates a hierarchical pose contextualization mechanism: global body configurations adaptively guide attention to local critical joints, yielding fine-grained pose embeddings and more precise interaction disambiguation. Owing to its modular design, PM-EQC integrates seamlessly with diverse backbones and benefits from their advances. Extensive experiments on PhysLab, HICO-DET, and V-COCO datasets demonstrate that PM-EQC achieves state-of-the-art performance, and the code is publicly available at https://github.com/ZMHSDUST/ PM-EQC.

Graph Neural Networks (GNNs) have demonstrated remarkable success in various scenarios. However, their impressive performance is under the assumption of class balance (i.e., equal training sample distribution across various categories). Once trapped in the class-imbalanced issue, the GNN-based models typically under-represent the minority ones, resulting in decreased performance compared to balanced graphs. A promising solution is to balance the graph in a generative manner. However, the existing studies overlook the consistency between the synthesized sample and its corresponding class. Furthermore, the homophily assumption (i.e., like attracts like) undermines the topological diversity of graphs, thereby complicating the capability of models to capture the true distribution and boundaries of the categories. To this end, we propose aConsistency-Aware andLooseHomophily guided generative method for class-imbalanced graphs, namelyGraphCALH. Specifically, we design a consistency-aware feature synthesis method to balance the node- wise characteristics and the class- wise commonality for the synthesized samples. Moreover, we devise a loose homophily guided topology modeling method to enrich the topological diversity and simplify category boundaries. The experimental results on eleven class-imbalanced datasets demonstrate that the proposed GraphCALH outperforms ten state-of-the-art methods. The source code of this work will be uploaded to Github.

Process execution time is a key performance indicator for evaluating bottlenecks in business processes. Cases and activities that exceed the specified time constraints can be seen as anomalies, affecting process performance and leading to risks such as delays and customer complaints. Identifying the root causes of these anomalies can help formulate effective intervention measures. However, this task is inherently complex, and conducting incomplete or inaccurate analysis can result in misguided interventions that inadvertently exacerbate process inefficiencies. To address these challenges, this paper proposes a traceability-based root cause analysis approach for process performance anomalies using causal inference. Specifically, the approach begins by extracting hidden contextual information from the event log to enrich the pool of potential causal factors. Then formulates causal hypotheses linking these factors to observed performance anomalies (at both the case and activity level) and establishes potential causal relations through a traceability mechanism. A meta-learning based causal inference approach is used to estimate the strength of causal effects. The proposed approach is evaluated against a state-of-the-art approach using four synthetic event logs with known root causes and nine public real-life event logs. Experimental results demonstrate that the proposed approach delivers accurate insights into the root causes of process performance anomalies in synthetic event logs, while maintaining high efficiency in the comprehensive analysis of potential causal factors.

Large volumes of event logs have been accumulated by business information systems. Accompanied by that, various process discovery techniques are invented to uncover underlying business processes based on event logs. Event log sampling, recognized as one of the most effective techniques for accelerating discovery efficiency, has gained significant attention in recent days. However, achieving high performance in sampling while maintaining superior sample log quality remains a challenge for current techniques. To tackle the problem, a novel event log sampling technique, denoted assigRank, is introduced to improve both the sampling efficiency and the quality of the sample log by quantifying the significance of each trace. The proposed sampling technique has been implemented as a publicly available tool in the open-source process mining platform ProM. Compared with state-of-the-art techniques using 12 public event logs, we experimentally illustrate that the proposed approach can significantly accelerate sampling efficiency while guaranteeing superior sample log quality for process discovery.

Process discovery aims to derive a process model that accurately represents the observed behavior in an event log. As a state-of-the-art process discovery technique, Inductive Miner (IM) generates sound process models (i.e., free of deadlocks) while ensuring optimal replay fitness. However, IM may sometimes produce over-generalized process models with locally imprecise structures, often resulting in the creation of so-called flower structures. To address this limitation, this paper presents a novel technique that refines the process model generated by IM by optimizing its imprecise sub-processes. Specifically, the technique begins by identifying and extracting sub-logs corresponding to imprecise sub-processes in the initial IM-generated process model. Then, these imprecise sub-processes are iteratively optimized using a frequency-based filtering mechanism applied to the sub-logs. Once optimized, the imprecise sub-processes in the initial process model are replaced by the optimized ones, generating a set of candidates process models. Finally, the candidate with the best quality, in terms of fitness and precision, is selected as the final optimized process models. The proposed technique has been implemented as a plugin for the open-source process mining platform ProM. Through comparisons with state-of-the-art process discovery techniques using 10 publicly available real-life event logs, the experimental results demonstrate that the proposed method achieves an average absolute improvement of 0.173 in F-measure over its IMi variant, while also exhibiting competitive performance relative to other state-of-the-art approaches.

The recommendation based on dynamic graph sequences aims to reveal complex evolutionary patterns in user-item interactions. Existing methods make predictions by encoding attribute contents through similarity but lack dynamic modeling of fine-grained attribute scenarios, resulting in a deviation in user interest representation. To address above issues, we propose a novel Dynamic Graph multi-granularity Attribute Scene evolution sequence Recommendation (DGASR) to enhance content features and reduce user interest bias by finer granularity modeling dynamic attributes. Firstly, we design an attribute-aware reconstruction module to model attribute interest distribution to reconstruct attributes and graphs. Subsequently, we design an attribute-aware long-short term module. It enhances long-term evolution characteristics of user behavior under attribute scene changes and constrains the consistency of users’ short-term interest distribution, achieving dynamic modeling of behavioral preferences under attribute scene distribution. Finally, DGASR achieves state-of-the-art results on three benchmark datasets, significantly outperforming several typical cold-start methods.

Heterogeneous Graph Neural Networks(HGNNs) are widely regarded as an effective tool for modeling data with graph structures in recommendation. Current research lacks modeling of user attribute and project attribute distribution preferences, limiting graph structure optimization potential. In response to these challenges, we propose a novel Heterogeneous Graph Dual-structure Optimization based Attribute-aware for Recommendation systems (HDSAR). It captures users’ personalized preferences through attribute-aware enhancement and uses dual-structure optimization to improve recommendation performance. First, we design an attribute-aware enhancement module to significantly enhance the relevance of attributes between users and items. Second, we use attribute-aware signals to explicitly filter heterogeneous neighbor ranges to preserve high- quality structural neighborhoods. Then, we employ contrastive learning to enhance the consistency of attribute-aware signals and heterogeneous structures to implicitly optimize the structural learning. Experiments on two real-world datasets demonstrate that HDSAR’s recommendation performance surpasses that of state-of-the-art methods.

The rapid expansion of Internet of Things (IoT) devices has led to an explosion of event data, posing significant challenges for traditional process model discovery techniques in terms of scalability and discovery accuracy. These techniques rely on centralized storage and processing, which are hindered by data transfer limitations, storage capacity, and computational overhead in distributed IoT environments. Edge-based model discovery techniques offer a promising solution for analyzing large-scale IoT data. However, existing techniques suffer from low efficiency and an inability to handle complex process structures. To address these challenges, we propose EdgeIM, an efficient edge-based process model discovery technique that enhances efficiency and model accuracy. EdgeIM operates in three key stages: preprocessing and feature-preserving sampling to eliminate redundant data, local processing at edge nodes to extract key structural features, and global feature aggregation at a central node for model discovery. EdgeIM has been implemented on the open-source process mining platform PM4Py, and experimental results on nine public event logs demonstrate that, compared to existing edge-based model discovery techniques, EdgeIM significantly improves discovery efficiency while maintaining high model quality.

Manufacturing process discovery extracts insights from event logs recorded by Manufacturing Information Systems (MISs) to optimize operational processes. However existing process discovery techniques struggle with complex concurrency relations, resulting in imprecise sub-processes that compromise model accuracy. This paper proposes a novel enhancement to Inductive Miner (IM)-generated models by optimizing local imprecise structures in manufacturing process models. The method first identifies imprecise sub-processes and extracts their corresponding sub-logs. Then imprecise sub-processes are incrementally optimized using a frequency-based filter mechanism, generating multiple candidate models. Finally, the best-quality candidate model based on evaluation metrics is selected as the final output. The proposed technique has been implemented as an open source process mining toolkit ProM plugin and evaluated on six real-life manufacturing event logs. Experimental results demonstrate that it outperforms state-of-the-art techniques, producing higher quality process models, making it particularly suited for manufacturing process discovery.

Class imbalance is a widespread problem in graph-structured data. The existing studies tailored for class-imbalanced graphs are typically categorized into generative and re-weighting methods. However, the former merely focuses on quantity balance rather than learning balance. The latter performs the fine-tuning in a majority-minority paradigm, overlooking the authentic-generative one. In fact, the collaboration of them is capable of relieving their respective limitations. To this end, we propose a Mutual-Guidance method for class-imbalanced graphs, namely GraphMuGu. Specifically, we first design an uncertainty-aware method to quantify the number of synthesized samples for each category. Furthermore, we devise a similarity-aware method to re-weight the importance of the authentic and generative samples. To the best our knowledge, the proposed GraphMuGu is the first try to incorporate the generative and re-weighting methods into a unified framework. The experimental results on five class-imbalanced datasets demonstrate the superiority of the proposed method. The source codes are available at https://github.com/ZZY-GraphMiningLab/GraphMuGu.

Graph Transformer has shown great promise in capturing the dynamics of user preferences for sequential recommendations. However, the self-attention mechanism within its structure is of quadratic complexity, posing challenges for deployment on devices with limited resources. To this end, we propose a Communal Linear Attention-enhanced Graph TransFormer for lightweight sequential recommendation, namely CoLA-Former. Specifically, we introduce a Communal Linear Attention (CoLAttention) mechanism. It utilizes low-rank yet reusable communal units to calculate the global correlations on sequential graphs. The weights from the units are also made communal across different training batches, enabling inter-batch global weighting. Moreover, we devise a low-rank approximation component. It utilizes weights distillation to reduce the scale of the trainable parameters in the Graph Transformer network. Extensive experimental results on three real-world datasets demonstrate that the proposed CoLA-Former significantly outperforms twelve state-of-the-art methods in accuracy and efficiency. The datasets and codes are available at https://github.com/ZZY-GraphMiningLab/CoLA_Former.

Visual parsing of images and videos is critical for a wide range of real-world applications. However, progress in this field is constrained by limitations of existing datasets: (1) limited annotation diversity, which limits the support for diverse vision tasks within a unified dataset; (2) insufficient coverage of domains, particularly a lack of datasets tailored for educational scenarios; and (3) a lack of explicit procedural guidance, with weak logical rules and insufficient representation of a structured task process. To address these gaps, we introduce PhysLab, the first dataset that captures students conducting complex physics experiments. The dataset includes four representative experiments that feature diverse scientific instruments and rich human-object interaction (HOI) patterns. PhysLab comprises 620 long-form videos and provides multi-granularity annotations that support a variety of vision tasks, including action recognition, object detection, HOI analysis, etc. We establish baselines and perform extensive evaluations to highlight key challenges in the parsing of procedural educational videos. We expect PhysLab to serve as a valuable resource for advancing comprehensive visual parsing, facilitating intelligent classroom systems, and fostering closer integration among computer vision, multimedia, and educational technologies. The dataset and the evaluation toolkit are publicly available at https://github.com/ZMH-SDUST/PhysLab.

ABSTRACT Pedestrian detection is crucial in agricultural environments to ensure the safe operation of intelligent machinery. In orchards, pedestrians exhibit unpredictable behavior and can pose significant challenges to navigation and operation. This demands reliable detection technologies that ensures safety while addressing the unique challenges of orchard environments, such as dense foliage, uneven terrain, and varying lighting conditions. To address this, we propose ReB‐DINO, a robust and accurate orchard pedestrian detection model based on an improved DINO. Initially, we improve the feature extraction module of DINO using structural re‐parameterization, enhancing accuracy and speed of the model during training and inference decoupling. In addition, a progressive feature fusion module is employed to fuse the extracted features and improve model accuracy. Finally, the network incorporates a convolutional block attention mechanism and an improved loss function to improve pedestrian detection rates. The experimental results demonstrate a 1.6% improvement in Recall on the NREC dataset compared to the baseline. Moreover, the results show a 4.2% improvement in and the number of parameters decreases by 40.2% compared to the original DINO. In the PiFO dataset, the with a threshold of 0.5 reaches 99.4%, demonstrating high detection accuracy in realistic scenarios. Therefore, our model enhances both detection accuracy and real‐time object detection capabilities in apple orchards, maintaining a lightweight attributes, surpassing mainstream object detection models.

ABSTRACT May‐Happen‐in‐Parallel (MHP) analysis serves as the basis for many concurrency bugs analyses. Inadequate handling of the coupling between locks and thread creation statements, as well as inter‐procedural locks, can lead to a loss of precision in MHP analysis. To address these issues, this paper proposes a new MHP analysis for C that operates at the segment granularity rather than individual statements. By constructing a Segmented Thread‐sensitive Control Flow Graph (STCFG) for a program, statements are grouped into different segments. Context information is added to these segments to capture the semantics of Pthreads operations, thereby identifying Happens‐Before (HB) and conflict relationships between segments. To compute MHP information for statement pairs, it is sufficient to examine the relationship between segments to infer the relationship between statements. We implement our algorithm in LLVM and evaluate it using eight test cases as well as four programs from the SPLASH2 benchmark suite. Preliminary results show that our method provides higher precision and achieves higher efficiency.

The prediction of remaining execution time is a critical area of research in business process monitoring. However, limited data availability and deficiencies in existing models have hindered progress in this area. To address these challenges, we introduce two production log datasets, coarse-grained log for television (CGL-TV) and fine-grained log for television (FGL-TV), collected from a semiautomated assembly line for television manufacturing. These datasets aim to address the issue of data scarcity in monitoring, analyzing, and optimizing the manufacturing process. Then, we investigate the significance of role information in semiautomated production processes and propose a novel feature selection strategy. That strategy replaces the traditional activity attributes with role attributes as the basis for prediction, resulting in a significant improvement in prediction accuracy. Furthermore, existing recurrent neural network (RNN)-based prediction methods have two major drawbacks: limited ability to capture long-term dependencies and the inability to parallelize computations. To address these issues, we propose a novel transformer-based remaining time prediction (TRTP) model. This model utilizes the self-attention mechanism instead of hidden state passing, which effectively incorporates global contextual information and enables potential parallel computing. The experimental results across four datasets demonstrate that our proposed method achieves state-of-the-art performance, e.g., a 5.2% performance gain on FGL-TV.

Mobile Edge Cache allows CDN edge nodes to be deployed closer to users, reducing content transmission latency in Vehicular Networks (VANETs). However, how to effectively utilize the limited storage space of cache nodes is the main issue in current research. To address this problem, we propose an incentive-driven hierarchical collaborative caching algorithm based on D3QN combined with user preferences (PC-ID3QN). Firstly, we constructed a UAV-assisted vehicular content-centric network framework, designing different collaborative caching strategy for various layers based on user preferences. Secondly, we proposed a hierarchical incentive mechanism based on social priority to motivate users to participate in collaborative sharing, thereby enhancing the utilization of system caching resources. Next, we modeled the cache placement problem as a system utility maximization problem and proved its NP-hardness. Then, by adjusting the constraint conditions, we conducted theoretical analysis and transform it into a linear programming(LP) problem to obtain an offline theoretical solution. This solution was validated against the simulation optimal solution obtained using the proposed PC-ID3QN algorithm, demonstrating the effectiveness of the algorithm. Finally, we validate the proposed caching strategy using the MovieLens dataset and conduct extensive experiments to verify the applicability and superiority of our solution in improving cache utility. Compared with DDQN, Dueling DQN and DQN, our proposed ID3QN algorithm reduces the request delay by 1.03%,1.73% and 2.21%, and reduces the energy cost by 38.8%, 19.6% and 17.2%, respectively.

Predictive Process Monitoring (PPM) aims to predict the future state of running process instances to enable timely interventions to mitigate potential risks. As one of the most fundamental tasks in PPM, process remaining time prediction focuses on preventing timeout occurrences. While various deep learning-based approaches have been developed for this purpose, they often rely on pre-established static prediction models and struggle to maintain accurate predictions when the process undergoes dynamic changes, such as an expanding sales channels. To tackle this challenge, this paper proposes an incremental process remaining time prediction framework by continuously updating the prediction model based on an incremental event log. Specifically, a feature selection strategy is first introduced to extract effective features from event logs. Leveraging effective features can significantly improve the prediction quality by capturing the changes in process information. Then, three incremental log-based updating mechanisms, including period-based updating, quantity-based updating, and concept-drift-based updating, along with a reconstruction strategy, are proposed to dynamically adjust the prediction model in response to business changes. Finally, LSTM, Transformer, and Auto-encoder models are adapted and integrated into the proposed framework. The approach has been implemented and publicly released. Experimental evaluation using nine real-life event logs demonstrate that the proposed framework and its three instantiations (i.e., LSTM-based, Transformer-based, and Auto-encoder-based ones) outperform state-of-the-art techniques in terms of prediction accuracy.

To cope with the dramatic growth of future network traffic and the diversity of services, beyond fifth-generation (B5G) and sixth-generation (6G) wireless communication need to balance the network load while being service-oriented. In this paper, we consider a multi-access edge computing (MEC) driven radio access network (RAN) slicing scenario in a heterogeneous cellular network (HetNet) with local traffic overload. First, since users are generally non absolutely rational when selecting base stations (BSs), an evolutionary game (EG) based user association (UA) scheme is proposed to solve the problem of overload. Specifically, we innovatively define the load function of the base stations (BSs) and combine resource capacity of BSs to form the payoff function to dynamically adjust the load. Second, we model the network slicing (NS) problem using the transmission rate, average latency and quality of service (QoS). The problem is further relaxed and an NS algorithm based on distributed successive convex approximation (DSCA) is presented to derive a theoretical upper bound reference value as a static offline criterion. Finally, considering the high randomness of user task arrival in the real scenario, we formulate the multi-base station slicing problem as a stochastic game (SG) and a multi-agent twin delayed deep deterministic policy gradient (MATD3)-based distributed network slicing algorithm is proposed to obtain excellent slicing strategies. Simulation results show that our proposed UA algorithm has a unique evolutionary equilibrium (EE) solution and is highly scalable. The proposed MATD3-based NS algorithm has better performance compared to other baseline algorithms and converges to a utility value that best approximates the theoretical upper bound.

Request for Comment (RFC) is a universal and standardized specification and describes internet protocol processes, algorithms, and standards. The formal representations of network protocols extracted from RFC can be used to verify correctness and security of the communication process. This paper proposes automatically extracting Petri net models from RFC protocol texts, transforming unstructured protocol text into a structured model. First, the RFC protocol text is preprocessed with chunking, part-of-speech, and element labeling. Second, element recognition is performed by the trained Bert-DGCNN-Bi-LSTM-CRF network, and a structured intermediate representation is generated based on the recognition results and semantic role relationships. Then, state transfer relations are extracted from the intermediate representation and stored in the correlation matrix. The correlation matrix is converted to a PNML file for visualization of Petri nets using PIPE software. Finally, an experimental comparative analysis of element recognition and relation extraction is conducted to prove the effectiveness of the extraction approach. Comparing the similarity between automatic and manual model extraction proves the quality of the extracted models.

In the upcoming 6G era, the demand for network communication and computing is expected to surge and diversify. A Space-Air-Ground Integrated Network (SAGIN) is introduced as a solution to provide seamless global connectivity. Meanwhile, network slicing technology can further enhance network capabilities by supporting customized services. However, the joint optimization of multi-dimensional resource allocation and task offloading decisions presents a significant challenge in dynamic and complex environments with diverse task types. In this work, we establish an SAG IN paradigm that integrates network slicing. A multi-level optimization scheme for resource allocation and task offloading is proposed to improve Key Performance Indicators (KPIs) and Quality of Service (QoS). Specifically, we propose a State Encoding-based Multi-Agent Soft Actor-Critic algorithm (SE- MASAC) within a Centralized Training with Decentralized Execution (CTDE) architecture. This algorithm processes current sensing states and historical information, leveraging reinforcement learning to make inter-slice resource and offloading scheduling decisions. Intra-slice decisions for intelligent User Equipments (iUEs) are determined based on their sensing data-driven priority. Simulation results demonstrate that our approach outperforms baselines in terms of system utility, QoS satisfaction, and various KPIs.

Summary Event log sampling has emerged as a key research focus in the field of process mining, aiming to enhance the efficiency of various process mining tasks, including model discovery, conformance checking, and process prediction. However, current log sampling techniques often fail to ensure high‐quality sample logs. This paper introduces a novel framework to support efficient event log sampling without compromising the quality of the sample log compared to the original one. The approach revolves around the consideration of directly‐follows relation (DFR) among business tasks as the fundamental behavior unit of an event log. By ensuring the DFR equivalence between the original and sample logs, the proposed technique addresses the challenge of sample log quality from the model discovery point of view. The framework is instantiated by seven distinct sampling strategies each has its own specialty and is fully implemented in the open‐source process mining tool platform ProM. To validate its effectiveness, we conducted a comprehensive experimental evaluation using 12 publicly available real‐life event logs against state‐of‐the‐art sampling techniques. The results clearly demonstrate that our technique significantly improves model discovery efficiency while upholding high quality of the discovered models.

In recent years, the study of real-world graphs has revealed their inherent heterogeneity, prompting growing research interest in heterogeneous graphs. Characterized by diverse node and relation types, heterogeneous graphs have led to the development of heterogeneous graph neural networks , which possess the remarkable ability of modeling such heterogeneity. Consequently, researchers have embraced these networks, applying them in various domains. A prevalent approach is using meta-path based methods in heterogeneous graph neural networks . However, a significant limitation arises from the fact that such methods tend to overlook vital attribute information within intermediate nodes and disregard relevant semantics across various meta-paths. To address the above limitations, we propose a new model named HGNN-MRCS. Specifically, HGNN-MRCS incorporates three key components, i.e., a relation aware module to encapsulate the attribute information of the intermediate nodes; a meta-path aware technique to facilitate learning of semantic information of each meta-path and enable higher-order representation learning ; and a knowledge distillation strategy to learn relevant semantics across meta-paths and fuse them. Experimental results on four real-world datasets demonstrate the superior performance of this work over the SOAT methods. The source codes of this work are available at https://github.com/ZZY-GraphMiningLab/HGNN-MRCS .

With the rapid development of applications with different use cases and service demands for edge network, network slicing is an emerging solution for satisfying service-oriented requirements, while the low earth orbit (LEO) satellite caching-assisted communication has been considered as one of the key elements for effective services. With limited resources at the edge of the radio access network (RAN), it is challenging to take advantage of the LEO content cache to joint allocation of communication, computing and caching space (3C) resources. To this end, we investigate the problem of resource slicing and scheduling of joint 3C resources in RAN edge scenario assisted by LEO content caching. A hierarchical resource slicing framework is proposed for dynamic allocation of multidimensional resources. The optimization variables are relaxed and the constraints are adjusted. The sequential quadratic programming (SQP) iteration algorithm is proposed as theoretical offline baseline. Due to its complex solving process and limited real-time performance, we incorporate Long Short-Term Memory (LSTM) into the Soft Actor-Critic (SAC) algorithm to aware extract the distribution characteristics of historical information and propose the deep reinforcement learning algorithm of LSTM-SAC. Meanwhile, the proportional priority based scheduling algorithm is employed in the intra-slice. Compared to SAC, TD3 and DDPG algorithms, the proposed algorithm is the closest to the theoretical value, improves the objective function by 6.95%, 9.52% and 11.52% respectively, which can significantly improve the system rate while satisfying the service level agreements.

Abstract Nested named entity recognition (NNER) aims to identify potentially overlapping named entities. Sequence labeling method and span-based method are two commonly used methods in nested named entity recognition. However, the linear structure of sequence labeling method results in relatively poor performance, and span-based method requires traversing all spans, which brings very high time complexity. All of them fail to effectively leverage the positional dependencies between internal and external entities. In order to improve these issues, this paper proposed a nested entity recognition method based on Multidimensional Features and Fuzzy Localization (MFFL). Firstly, this method adopted the shared encoding that fused three features of characters, words, and parts of speech to obtain a multidimensional feature vector representation of the text and obtained rich semantic information in the text. Secondly, we proposed to use the fuzzy localization to assist the model in pinpointing the potential locations of entities. Finally, in the entity classification, it used a window to expand the sub-sequence and enumerate possible candidate entities and predicted the classification labels of these candidate entities. In order to alleviate the problem of error propagation and effectively learn the correlation between fuzzy localization and classification labels, we adopted multi-task learning strategy. This paper conducted several experiments on two public datasets. The experimental results showed that the proposed method achieves ideal results in both nested entity recognition and non-nested entity recognition tasks, and significantly reduced the time complexity of nested entity recognition.

The Gate Recurrent Unit (GRU) has a large blank in the application of legal transition sequences for bounded Petri nets. A GRU-based method is proposed for the recognition of bounded Petri net legal transition sequences. First, in a Petri net, legal and non-legal transition sequences are generated according to a certain noise ratio. Then, the legal and non-legal transition sequences are inputted into GRU to recognize the legal transition sequences by encoding the maximum variation sequence length with a uniform length. The proposed method is validated with different Petri nets at different noise ratios and compared with seven widely-known baselines. The results show that the proposed method achieves excellent recognition accuracy and robustness in most situations. Solving the problem that the existing methods cannot recognize the legal transition sequences of Petri nets in real time.

Action learning is a research area that aims to recognize the action category of each frame in the video. Context information is crucial for learning actions, but most existing methods face two challenges in exploiting this information: 1) They apply global attention to aggregate global features for action representation, resulting in inefficiency and redundancy. 2) They impose implicit action constraints to regularize the action distribution, leading to subjectivity, interpretability issues, and optimization difficulties. To address these challenges, we propose an end-to-end weakly-supervised Action Learning framework with Process Knowledge Decomposition (AL-PKD), which leverages the intrinsic characteristics of procedural task videos. To enhance the effectiveness and adaptability of context aggregation, we first design the TEAL-Net action recognition network. Specifically, the TEAL-Net accounts for the diverse neighbor distributions of action nodes across categories and collects local neighborhood features with different receptive fields through feature pyramids, improving the accuracy and efficiency of action representation. Moreover, to overcome the drawbacks of implicit constraint strategies, we next employ process mining techniques to extract three types of explicit action pair constraints: sequentiality, concurrency, and selectivity. These constraints guide the model’s predictions and improve the interpretability of the learning process. Finally, we use the Viterbi algorithm to dynamically infer the optimal action boundaries based on the frame-level predictions, which helps to eliminate local misclassifications. Experiments on three datasets of Breakfast, CrossTask, and PEVD demonstrate that our method achieves state-of-the-art performance.

With the development of Intelligent Transportation Systems (ITS), edge caching has gradually emerged as a critical technology to reduce transmission delay and optimize network load. However, the limited storage capacity and service scope of individual cache servers significantly degrade the performance of edge caching. To address this issue, we propose a social-aware assisted edge collaborative caching algorithm based on Dueling Double Deep Q-Network and Digital Twin Network (SACTD-D3). The algorithm can dynamically adjust the caching decision based on the similarity of user semantic information and the availability of edge services to fully utilize the caching capacity of edge servers. Firstly, vehicle clusters are formed based on users’ semantic similarity, and an on-board cloud is constructed to reduce user request delay by sinking edge services. Secondly, based on the establishment of the three-layer structure of macro base station, roadside units and on-board cloud, the content heat-based caching decision policy is utilized to effectively improve the content cache hit rate. Moreover, an optimization problem is formulated to maximize the overall utility of the system subject to transmission delay and system cost, and thus the optimal solution is obtained using the proposed$\varepsilon$-greedy SACTD-D3 algorithm. Furthermore, due to the dynamic complexity of the network topology, digital twin is used to simplify and map the network topology into digital twin networks for analysis and processing to improve network efficiency. Finally, the simulation results demonstrate the effectiveness of the proposed algorithm in improving the system performance. Compared with Double DQN, Dueling DQN and DQN, the proposed SACTD-D3 algorithm reduces the request delay by 2.62$\%$, 3.06$\%$and 3.95$\%$, and reduces the energy cost by 26.07$\%$, 47.05$\%$and 49.90$\%$, respectively.

Predictive Process Monitoringaims to predict the future information of ongoing process executions by leveraging machine and deep learning techniques. One of the tasks is known asremaining time prediction, which focuses on predicting the remaining time of ongoing cases. Accurate remaining time prediction can be valuable and important for improving business operations or taking timely interventions to prevent delays. For predicting the remaining time, existing work has used deep learning techniques to achieve high prediction accuracy. However, most of these techniques tend to learn very complex models that are difficult to explain. Systematic feature selection approaches may help improve both the prediction accuracy and the explainability of the model. In this paper, we introduce a feature-informed cascade prediction framework to predict the remaining time. Specifically, we first propose an approach that builds a tree of features by systematically estimating their effects on the remaining time prediction. Next, we use the tree to either automatically select an optimal combination of features or to guide users in this selection process. Each selected feature is correlated with its prediction results in our Feature-informed Cascade Prediction Model (FCPM) for explainability. The proposed approach has been implemented and is made publicly available. Using eight public real-life event logs, the proposed approach is compared to the state-of-the-art approaches in terms of prediction accuracy. In addition, it is demonstrated that our approach visualizes the impact of each input feature in the prediction of individual cases, producing explanations of the prediction results.

Process discovery aims to extract descriptive process models from event logs. To date, various process discovery algorithms have been proposed for different application settings. However, most of them meet challenges in handling event logs produced from hierarchical multi-instance business processes, in which multiple sub-process instances are invoked by the execution of a parent process. To address the problem, a novel approach is presented to support the discovery of hierarchical multi-instance process models. Specifically, taking event logs with multi-instance information as input, the detailed implementation of our method can be generally divided into four steps: nesting relation detection, hierarchical event log construction, sub-process case identification, and hierarchical multi-instance model discovery. We have implemented our approach properly as plugins in the openly accessible ProM toolkit, and compared its performance against the state-of-the-art process discovery approaches over six publicly available event logs. Based on the experimental result, it is demonstrated that the proposed approach can effectively discover hierarchical multi-instance process models with better quality.

Existing pest image classification models require a large number of labeled training images. However, labels for most pest images in the real world do not exist. Therefore, the zero-shot learning method based on generative meta-learning provides an effective solution, which first uses attributes to transfer knowledge from seen classes to unseen classes, and then synthesizes the features of unseen classes. We observe that seen and unseen classes share the same high-level attributes, which can be used to learn a shared set of optimal parameters for seen and unseen classes. Therefore, we propose a novel Hierarchical Class level Attribute guided Generative meta model for pest image Zero-shot Learning (HCAG-ZSL). HCAG-ZSL uses the pre-built Taxonomic Attribute Tree to get the high-level attributes corresponding to the class attributes. These attributes are then fed into a well-designed generator to generate visual features. Extensive experiments show that the proposed model outperforms state-of-the-art generative meta models.

Forming a stable autonomous vehicle group is extremely challenging in an urban scene, which is disturbed by many environmental factors, e.g., manned vehicles, roadside obstacles, traffic lights, and pedestrians. Existing work focuses on autonomous vehicle group formation (AVGF) in a highway scene only. Its outcomes cannot be directly applied to an urban scene because of different environmental factors and poor communication quality. This work presents an autonomous vehicle group model in an urban scene. First, it proposes a prediction method to analyze the impact of environmental factors on communications among autonomous vehicles. Then, it defines preperception degree, vehicle activity, and mobility similarity of autonomous vehicles and selects leader vehicles based on them. Next, it measures connectivity, coupling, and timeliness increments of a vehicle group, based on which a vehicle group model is formulated. Finally, it solves the proposed vehicle group model by using a modified distributed multiobjective optimization method, proves its convergence, and analyzes its time complexity. The simulation results on synthetic and real roads show that the proposed prediction method achieves lower errors than XGBoost and a multilayer perceptron, and the proposed vehicle group model outperforms two AVGF methods and a dynamic clustering method for vehicular ad-hoc network.

Due to buildings blocking GPS and Wi-Fi signals, traditional techniques can't offer the user's required positioning accuracy in resource-constrained underground parking, but the cooperation of agent nodes can provide the exact localization information to improve the positioning accuracy. However, some well-localized agents may not be willing to sacrifice additional power to improve the others' positioning accuracy. To encourage cooperation among nodes and allocate transmission power reasonably, this paper proposes a bidding-auction-based cooperative localization (BACL) algorithm to improve the positioning accuracy of agent nodes by joint node selection incentive and power allocation strategy. Firstly, the contribution of channel parameters and prior localization information of agent nodes for positioning accuracy are quantified and an incentive mechanism of cooperative localization from an economic perspective is proposed. Secondly, a virtual currency incentive rule is developed to compensate agent nodes of cooperative localization reasonably due to the consumption of energy for transmitting their location information. Finally, the simulation results have shown that the proposed BACL algorithm has excellent performance in terms of localization accuracy in resource-constrained scenarios. Compared with the full-power cooperative localization (FPCL) and non-cooperative localization (NCL) algorithms, the proposed BACL algorithm improved the positioning accuracy by 10% and 65%, respectively. Meanwhile, compared with the FPCL algorithm, the proposed algorithm reduced resource consumption by 50%.

With the continuous development of the Internet of Vehicles(IoV), Vehicle Edge Computing(VEC) has become a key technology for computational resource scheduling, but more and more smart devices are connected to the internet, which makes it difficult for traditional Vehicle Edge Networks(VEN) to deal with tasks in time. In this paper, in order to cope with the challenges of the large number of devices accessing the internet, we propose a vehicle-assisted computation offloading algorithm based on proximal policy optimization(VCOPPO) for User Equipment(UE) tasks, and it combines dynamic parked vehicles incentives mechanism and computational resource allocation strategy by using road vehicles and parked vehicles as edge servers. Firstly, a non-convex optimization problem combining VEN utility and task processing delay is formulated, subject to the constraints of the residual energy and the transmission rate of the task. Secondly, the proposed VCOPPO is used to solve the formulated non-convex optimization problem, and we use stochastic policy to obtain the optimal computation offloading decisions and resource allocation schemes. Finally, the experimental results have shown that the proposed VCOPPO has an excellent performance in network reward and task processing delay respectively, and it can effectively schedule and allocate computational resources. Compared with using Dueling Deep Q Network(Dueling DQN), Deep Q Network(DQN) and Q-learning methods, the proposed VCOPPO improves the network reward by 31%, 18% and 91%, reduces the delay in task processing by 78%, 63% and 74%, respectively.

Healthcare plays an increasingly essential role in our daily life. Modern Hospital Information Systems (HISs) record and store detailed medical treatment process information for all patients as event logs. By taking event logs as input, process mining techniques have been widely applied to extract valuable insights to improve medical treatment processes and deliver better healthcare services. However, considering the complexity of collaborations among different medical departments, existing model discovery techniques cannot be applied directly. To handle this limitation, this paper proposes a novel approach to support the discovery of Cross-department Collaborative Healthcare Process (CCHP) models from medical event logs. Specifically, an extension of classical Petri Nets with message and resource attributes is first introduced to formalize CCHPs. Then, a novel discovery algorithm is proposed to discover Intra-department Healthcare Process (IHP) models. Next, collaboration patterns among medical departments are formalized and corresponding discovery algorithms are given on that basis. Finally, a global CCHP model is obtained by integrating all discovered collaboration patterns and IHP models. By using four public medical event logs, we quantitatively compare our approach with the state-of-the-art process mining techniques in terms of model quality, and our experimental results demonstrate that the proposed approach can discover more accurate healthcare process models.Note to Practitioners—The recorded medical event logs by HISs can be used to extract valuable insights for the analysis of healthcare processes. However, existing process model discovery techniques cannot be applied for the analysis directly due to the complex collaborations among different medical departments of a hospital. This paper introduces a novel approach for cross-department collaborative healthcare process model discovery from medical event logs. All proposed techniques are fully implemented and publicly available. Using four public medical event logs, we show the applicability and advantages of our approach against existing ones. The proposed techniques are applicable to the model discovery and behavior understanding of real-life operational healthcare processes.

Graphs are widely used to model various practical applications. In recent years, graph convolution networks (GCNs) have attracted increasing attention due to the extension of convolution operation from traditional grid data to graph one. However, the representation ability of current GCNs is undoubtedly limited because existing work fails to consider feature interactions. Toward this end, we propose a Dual Feature Interaction-based GCN. Specifically, it models feature interaction in the aspects of 1) node features where we use Newton's identity to extract different-order cross features implicit in the original features and design an attention mechanism to fuse them; and 2) graph convolution where we capture the pairwise interactions among nodes in the neighborhood to expand a weighted sum operation. We evaluate the proposed model with graph data from different fields, and the experimental results on semi-supervised node classification and link prediction demonstrate the effectiveness of the proposed GCN. The data and source codes of this work are available athttps://github.com/ZZY-GraphMiningLab/DFI-GCN.

Business processes are critical for information systems to control workflows and deliver services. Although existing process discovery techniques can generate flat process models from business event logs, few of them have investigated the notion of hierarchy (i.e., subprocesses) yet. To fill the gap, this article first defines the concept of hierarchical Petri nets (HPNs), which can support the formal modeling and correctness verification of processes with subprocesses. Followed by that, we propose an approach which can effectively discover HPNs from event logs with lifecycle information. Moreover, to quantify the quality of discovered HPNs, details on how to transform an HPN to a classical Petri net are given such that existing metrics can be applied. All proposed approaches have been fully implemented in ProM, and experiments over both synthetic and real-life event logs demonstrate that our approach can effectively discover hierarchical process models. Specifically, compared to exiting approaches on processes discovery, our approach can generally perform better in terms of model quality.

As an important task in business process management, remaining time prediction for business process instances has attracted extensive attentions. However, most of the traditional remaining time prediction approaches only take into account formal process models and cannot handle large-scale event logs in an effective manner. Although machine learning and deep learning have been recently applied to the remaining time prediction task, these approaches cannot incorporate domain knowledge naturally. To overcome these weaknesses of existing studies, we propose a remaining execution time prediction approach based on a novel auto-encoded transition system, which can enhance the complementarity of process modeling and deep learning techniques. Through auto-encoding the event-level and state-level features, the proposed approach can represent process instances in a comprehensive and compact form. Furthermore, a transfer learning strategy is proposed to train the remaining time prediction model so as to avoid overfitting and improve the accuracy of prediction. We conduct extensive experiments on four real-world datasets to verify the effectiveness of the proposed approach. The results show its superiority over several state-of-the-art approaches.

Business process similarity measures are of vital importance for process repository management applications, such as process query, process recommendation, and process clustering. Most existing approaches measure process similarity by relying on control-flow structures only. This article investigates the role of data in process similarity measure. To incorporate data-flow information into business process control flow, it proposes a data-aware workflow net (DWF-net) by extending the classical workflow net with data reading and writing semantics. Then, we introduce three types of similarity measures, i.e., data item set-based similarity, data operation set-based similarity, and data-aware behavior-based similarity, to quantify the similarity of data-aware business processes from different perspectives. Next, a methodology is introduced to help process analysts apply these three measures in a systematical way. Finally, we evaluate the effectiveness and applicability of the proposed similarity measures by a group of comparative experiments.

Summary Modern information systems are continuously collecting and storing large volumes of business process event logs. The analysis of event logs can provide valuable insights for business process re‐engineering and enhancement. Process discovery, as one of the most challenging event log analysis techniques, aims to discover a business process model from an event log. Many process discovery approaches have been proposed in the past two decades, however, most of them suffer from efficiency problem when dealing with large‐scale event logs. Motivated by PageRank, we propose LogRank, a graph‐based ranking model, for event log sampling in this paper. The LogRank is capable of sampling a large‐scale event log to a smaller size that can be efficiently handled by existing discovery approaches. To support real‐life applications, we instantiate the LogRank model for two typical types of event logs, that is, simple event logs and lifecycle event logs. To quantify the quality of a sample log with respect to the original one, we introduce a general evaluation framework that can be instantiated for different quality metrics. The proposed sampling approach has been implemented in the open‐source process mining toolkit ProM. By experiments with both synthetic and real‐life event logs, we demonstrate that the proposed LogRank‐based sampling approach provides an effective means to improve process discovery efficiency as well as guaranteeing high quality of discovered models.

Domain terminologies are a basic resource for various natural language processing tasks. To automatically discover terminologies for a domain of interest, most traditional approaches mostly rely on a domain-specific corpus given in advance; thus, the performance of traditional approaches can only be guaranteed when collecting a high-quality domain-specific corpus, which requires extensive human involvement and domain expertise. In this article, we propose a novel approach that is capable of automatically mining domain terminologies using search engine's query log—a type of domain-independent corpus of higher availability, coverage, and timeliness than a manually collected domain-specific corpus. In particular, we represent query log as a heterogeneous network and formulate the task of mining domain terminology as transductive learning on the heterogeneous network. In the proposed approach, the manifold structure of domain-specificity inherent in query log is captured by using a novel network embedding algorithm and further exploited to reduce the need for the manual annotation efforts for domain terminology classification. We select Agriculture and Healthcare as the target domains and experiment using a real query log from a commercial search engine. Experimental results show that the proposed approach outperforms several state-of-the-art approaches.

Workflow management technology has become a key means to improve enterprise productivity. More and more workflow systems are crossing organizational boundaries and may involve multiple interacting organizations. This article focuses on a type of loosely coupled workflow architecture with collaborative tasks, i.e., each business partner owns its private business process and is able to operate independently, and all involved organizations need to be synchronized at a certain point to complete certain public tasks. Because of each organization’s privacy consideration, they are unwilling to share the business details with others. In this way, traditional correctness verification approaches via reachability analysis are not practical as a global business process model is unavailable for privacy preservation. To ensure its globally correct execution, this work establishes a correctness verification approach for the cross-organizational workflow with task synchronization patterns. Its core idea is to use local correctness of each suborganizational workflow process to guarantee its global correctness. We prove that the proposed approach can be used to investigate the behavioral property preservation when synthesizing suborganizational workflows via collaborative tasks. A medical diagnosis running case is used to illustrate the applicability of the proposed approaches.Note to Practitioners—Cross-organizational workflow verification techniques play an increasingly important role in ensuring the correct execution of collaborative enterprise businesses. This work addresses the issue of correctness verification for loosely coupled interactive workflows with collaborative tasks. To ensure the globally correct execution, a behavioral correctness verification approach is established. All proposed concepts and techniques are supported by open-source tools, and evaluation over a medical diagnosis process case has shown their applicability. The proposed methodology is readily applicable to industrial-size workflow correctness verification problems.

In the October 2017 issue of the IEEE Transactions on Automation Science and Engineering[1], there are several errors, reported and corrected as follows.

When an emergency occurs, one of the important challenges is how to form an effective and timely response. An emergency disposal plan is usually organized as a series of emergency response processes manipulated by one emergency command center and several subordinate emergency organizations. Moreover, these subordinate organizations are usually geographically dispersed and need to collaborate with each other. In this case, designing and verifying such cross-organizational collaborative emergency response processes are complicated and time-consuming. To address this problem, we propose a hierarchical modeling and correctness verification approach. A general framework for hierarchical modeling and correctness verification of such processes is first introduced. Then, a top-level model and two kinds of bottom-level models (complex and simple bottom-level ones) are proposed to model such processes and collaboration patterns from different abstraction levels. Next, Petri net refinement operation is adopted to refine the top-level model by using its corresponding bottom-level models to obtain the refined model. Finally, the correctness of the refined model is verified based on reachability graph. A typical running case of cross-organization collaborative fire emergency response processes is given to validate our proposed method.

A group of geographically dispersed and logically collaborated emergency organizations are involved when emergency occurs. Two challenging issues are a reasonable emergency resource allocation mechanism and an efficient resource conflict checking and resolution control mechanism to ensure the conflict-free execution of global cross-organization emergency response processes. To address them, this paper proposes an approach to support emergency resource management including both intraorganization private resource management and cross-organization public resource management. The former has been fully discussed in our previous work using E-net. To cope with the latter, this paper presents a novel type of Petri net that is extended with both time and resource factors to model cross-organization emergency response processes. Then, according to the resource requirement analysis, their worst, delayed, and best cases are obtained. Next, emergency resource conflict checking and four conflict resolution strategies are proposed to resolve the detected resource conflicts for the delayed execution case. This paper shows how to use different resolution strategies to construct the conflict-free model by designing corresponding resolution controllers. Finally, their performance is evaluated by a fire emergency response example.

More and more business requirements are crossing organizational boundaries. There comes the cross-organization business process management, and its modeling is a complicated task. Mining a cross-organization business process aims to discover its model from a set of distributed event logs. Unfortunately, traditional process mining approaches totally neglect the privacy-preservation issue, which means the privacy of both event log and business process model. In this paper, a privacy-preservation cross-organization business process mining framework is proposed to handle its privacy issues. It includes three steps: (1) each organization discovers its private and public business process models from its event logs; (2) the trusted third-party midware takes the public process models as input and generates cooperative public process model fragments of each organization; and (3) each organization combines its private business process model with its relevant public fragments to obtain the organization-specific cross-organization cooperative business process model. To illustrate the applicability of the proposed approach, a multi-modal cross-organization transportation case is used for its validation and comparison with other methods.

Deadlock detection plays an important role in the analysis of system behavior. Several kinds of reachability trees have been proposed to analyze Petri net properties including deadlock freedom. However, existing reachability trees can only solve the deadlock detection problem of bounded or some special kinds of unbounded Petri nets. To increase the applicable scope of reachability trees in the deadlock detection field, this paper presents a new type of reachability trees called complex reachability tree (CRT). Different from others, transition sequences corresponding to root-started paths of cyclic CRTs are always firable from the initial marking. The proposed trees can completely solve the deadlock detection problem of ω-gone node-free Petri nets, but cannot guarantee to detect all the deadlocks for the other kinds of unbounded Petri nets. Their construction method and applications are presented.

Polar code has been proven to achieve the symmetric capacity of memoryless channels. However, the successive cancellation decoding algorithm is inherent serial in nature, which will lead to high latency and low throughput. In order to obtain high throughput, we design a deeply pipelined polar decoder and optimize the processing elements and storage structure. We also propose an improved fixed‐point nonuniform quantization scheme, and it is close to the floating‐point performance. Two‐level control strategy is presented to simplify the controller. In addition, we adopt FIFO structure to implement the α _memory and β _memory and propose the 348‐stage pipeline decoder.

Traditional process discovery techniques mine process models based upon event traces giving little consideration to workflow relevant data recorded in event logs. The neglect of such information usually leads to incorrect discovered models, especially when activities have decomposable cyclic dependencies. To address this problem, the recorded workflow relevant data and decision tree learning technique are utilized to classify cases into case clusters. Each case cluster contains causality and concurrency activity dependencies only. Then, a set of activity ordering relations are derived based on case clusters. And a synchronization-core-based process model is discovered from the ordering relations and composite cases. Finally, the discovered model is transformed to a BPMN model. The proposed approach is validated with a medical treatment process and an open event log. Meanwhile, a prototype system is presented.

Web service composition is a challenging research issue. This paper presents an automatic Web service composition method that deals with both input/output compatibility and behavioral constraint compatibility of fuzzy semantic services. First, user input and output requirements are modeled as a set of facts and a goal statement in the Horn clauses, respectively. A service composition problem is transformed into a Horn clause logic reasoning problem. Next, a Fuzzy Predicate Petri Net (FPPN) is applied to model the Horn clause set, and T-invariant technique is used to determine the existence of composite services fulfilling the user input/output requirements. Then, two algorithms are presented to obtain the composite service satisfying behavioral constraints, as well as to construct an FPPN model that shows the calling order of the selected services.

Time and resource management and optimization are two important challenges for an emergency response process, by which all individuals and groups manage hazards in an effort to avoid or ameliorate the impact of disasters. Compared with a traditional business process, an emergency response process has its own features. To our best knowledge, there is no formal method to model and analyze emergency response processes by taking uncertain activity execution duration, resource quantity, and resource preparation duration into account. This paper presents such a method based on an E-Net that is a Petri net-based formal model for an emergency response process constrained by resources and uncertain durations. According to the number of available resources, execution of an E-Net is classified into the worst, delayed, and best cases. Based on a priority-activity-first strategy and corresponding algorithms, this paper finds the duration to execute each activity for the delayed case. By experiments, we prove that the proposed strategy can ensure shorter execution duration of the whole process than a conventional one. A running case of a chlorine tank explosion is given to validate the proposed method.

Recently, cross-department business processes are becoming more and more complex. Different kinds of coordination patterns exist among different departments, which make modeling and analysis work more difficult. To our best knowledge, there is no formal method to give systematic modeling and verification for the cross-department processes when considering different kinds of coordination patterns among different departments. This paper proposes such a method based on Petri nets. The WF-net model extended with resource and message factors, RM_WF_Net for short, is first introduced. Then, the formal model of tasks is proposed and its coordination relations are given. Next, RM_WF_Net modeling for intradepartment processes is investigated and cross-department coordination patterns, including message interaction pattern, resource interaction pattern, task collaboration pattern, procedure abstract, service outsourcing pattern, and process activation pattern, are formally defined. The soundness of the RM_WF_Net is verified based on the reachability graph. A running case of the cross-department medical diagnosis business process is given to validate our proposed method.

Petri nets are suitable for modeling and analysis of business processes. However, the lack of data concepts often makes Petri-net-based models excessively large and difficult to analyze especially when process logic is sensitive to changes of process attribute values. Emergency treatment processes are a typical example of this situation. To solve the aforementioned problems, this paper proposes a new hierarchical Petri net model for modeling and verification of emergency treatment processes. The hierarchical Petri net model includes three separate but closely related models, i.e., a business process logic net, a business process semantic net, and a set of case models. Business process logic nets are used to model the task dependencies disregarding semantic information. Business process semantic nets introduce data concepts to business process logic nets to model semantic information such as process attributes or conditions of sequence flows. Case models are used to model the practical routes of specific business instances. Based on the three models, a formal verification algorithm of an emergency treatment process is presented. Finally, the hierarchical modeling and verification methods are validated by an emergency treatment process of highways under snow/ice weather conditions.

A complex workflow is often executed by geographically dispersed partners or different organizations. As a solution for dealing with the decentralized nature of workflow applications, a workflow can be fragmented into small pieces and scheduled to different servers for its execution. An important challenge in distributed workflows is to optimize the fragmentation and distribution to achieve efficiency with respect to time and server resources. To tackle this challenge, we propose the application of process mining to the fragmentation of a workflow for distributed execution. The workflow model discovered through process mining records the actual execution of a workflow and allows in-depth analysis of its temporal behavior. Based on examination of the model resulting from process mining, we demonstrate how to determine the minimum time to finish a workflow and how to partition the workflow in order to achieve efficient server usage.

Abstract A new type of semantic pattern is proposed in this paper, which can be used by users to post questions and answers in user‐interactive question answering (QA) systems. The necessary procedures of using semantic patterns in a QA system are also presented, which include question structure analysis, pattern matching, pattern generation, pattern classification and answer extraction. Both the manual creation method and the automatic generation method are proposed for patterns for different applications. A pattern instantiation level metrics is also presented for the predication of the quality of generated or learned patterns. We implemented a user interface for using the semantic pattern in our QA system, which allows users to effectively post and answer questions. Copyright © 2007 John Wiley & Sons, Ltd.

Time and resource management and verification are two important aspects of workflow management systems. In this paper, we present a modeling and analysis approach for a kind of workflow constrained by resources and nondetermined time based on Petri nets. Different from previous modeling approaches, there are two kinds of places in our model to represent the activities and resources of a workflow, respectively. For each activity place, its input and output transitions represent the start and termination of the activity, respectively, and there are two timing functions in it to define the minimum and maximum duration times of the corresponding activity. Using the constructed Petri net model, the earliest and latest times to start each activity can be calculated. With the reachability graph of the Petri net model, the timing factors influencing the implementation of the workflow can be calculated and verified. In this paper, the sufficient conditions for the existence of the best implementation case of a workflow are proved, and the method for obtaining such an implementation case is presented. The obtained results will benefit the evaluation and verification of the implementation of a workflow constrained by resources and nondetermined time.

Abstract In this paper, we propose a user reputation model and apply it to a user‐interactive question answering system. It combines the social network analysis approach and the user rating approach. Social network analysis is applied to analyze the impact of participant users' relations to their reputations. User rating is used to acquire direct judgment of a user's reputation based on other users' experiences with this user. Preliminary experiments show that the computed reputations based on our proposed reputation model can reflect the actual reputations of the simulated roles and therefore can fit in well with our user‐interactive question answering system. Copyright © 2006 John Wiley & Sons, Ltd.