The Internet of Things (IoT) revolution has led to unprecedented data generation, necessitating a shift from traditional centralized computing to more decentralized approaches. To address the challenges of data processing closer to the source, the paradigm of Mobile Edge Computing (MEC) has emerged. It facilitates task offloading to nearby edge servers, thereby reducing delay and enhancing privacy. However, limited computation resources at the edge necessitate intelligent resource allocation through effective scheduling to maintain Quality of Service (QoS). Typically, a task comprises multiple subtasks with inherent dependencies, some of which are locally dependent and unsuitable for offloading. In subtask scheduling, one must account for both inter-subtask and local dependencies, deploying different subtask types to near-optimal computing devices, whether edge servers or User Equipment (UEs). This requirement presents significant challenges to scheduling strategies. Furthermore, since task offloading requests are inherently online, without prior task information before their arrival, improper scheduling can result in resource wastage and increased delays. To tackle these challenges, we formulate the Online Multi-DAG task Scheduling with Dependency awareness (OMSD) problem within a DAG-MEC framework. This problem is modeled as an Integer Linear Programming (ILP) problem and proven to be NP-hard. We propose a Dynamic Priority List Scheduling (DPLS) algorithm to address this problem effectively. Our algorithm strategically determines subtask execution order by evaluating upward and downward ranks, task volume, and contention levels. Simulation results demonstrate that DPLS significantly outperforms existing benchmark algorithms regarding mean task completion time, server load balance, and maximum task completion time, offering a robust solution to the OMSD challenge in MEC environments.

Graph-based Retrieval-Augmented Generation (RAG) has achieved remarkable success in refining the outputs of Large Language Models (LLMs), enabling them to integrate relational and multi-hop knowledge into context-aware responses by constructing a knowledge graph from an external database. In this paper, we focus on the underexplored security risks arising from the external database, and propose the first backdoor attacks against the graph-based RAG of LLMs. Specifically, attackers insert the backdoor into the knowledge graph as entities by poisoning a carefully crafted corpus into the external database, thereby causing LLMs to output attacker-desired answers for trigger-containing queries while preserving correct answers for others. The attacks are formulated as a minimax problem, whose solution is a poison corpus. Powered by the chain-of-thought reasoning capabilities of LLMs, we propose a new strategy to solve the minimax problem. We craft retrieval text to insert triggers into the knowledge graph as entities, exploit hijacking text to redirect LLMs’ attention toward attacker-desired answers, and finally link the hijacking text to the triggers so that it serves as context only for trigger-containing queries. In addition, our attacks involve three types of triggers, including word-level, topic-level, and semantic-level, with progressively increasing stealthiness. Empirical results across multiple knowledge databases and language models indicate that the proposed attacks achieve the desired attack performance. Our findings highlight the substantial risks in LLM applications (e.g., chatbots and agents) built on graph-based RAG systems.

Edge computing brings computational resources to network edge, enabling mobile devices (MDs) to offload computing-intensive tasks to nearby edge servers. This significantly reduces the energy consumption of MDs and supports latency-sensitive applications. Meanwhile, the advancement of full-duplex (FD) cell-free massive multiple-input multiple-output (MIMO) technology provides a promising opportunity to enhance end-edge communication efficiency, particularly in scenarios with coexisting uplink (UL) and downlink (DL) users. In this paper, we investigate the joint task offloading and resource scheduling problem in FD cell-free massive MIMO-enabled edge computing networks. The problem is formulated as a two-stage optimization framework. In the first stage, we develop a hybrid simulated annealing–particle swarm optimization (SA-PSO) algorithm, which incorporates the Metropolis criterion to enhance global search capability, aiming to maximize spectral efficiency. In the second stage, we propose a diffusion-augmented prioritized deep deterministic policy gradient (DAP-DDPG) algorithm. This algorithm integrates prioritized experience replay with diffusion models to minimize the total energy consumption of MDs while satisfying stringent latency constraints. Simulation results demonstrate that, compared with benchmark schemes, the proposed SA-PSO algorithm achieves a 13.4% to 146% improvement in spectral efficiency, while the DAP-DDPG algorithm reduces the energy consumption of MDs by 12.5% to 33.1%.

Federated learning enables training across multiple entities while ensuring data security and the effectiveness of knowledge dissemination. Despite its benefits, it remains susceptible to privacy breaches by both external and internal adversaries, who may exploit data or model parameters to glean sensitive participant information or disrupt the training process, thus compromising participant privacy and security. This paper proposes a novel methodology, Adversarial Samples for Defense Inference Attack (ASDIA), aimed at dual protection of data privacy and model robustness within federated learning through adversarial samples and gradient reconstruction. ASDIA includes gradient processing approach before uploading: initially identifying privacy-sensitive gradient, followed by the injection of well-calibrated noise to these gradients. This method not only obfuscates the adversary's classification demarcations but also aids in model performance recovery, all the while maintaining computational efficiency. ASDIA reduces the efficacy of attacks to near-random guessing levels and shows better balance between the model utility and privacy protection compared to the most advanced defense strategies. Additionally, regarding model performance, ASDIA proves its merit across diverse datasets under overfitting and non-overfitting scenarios.

Edge computing (EC) reduces task processing and content download delay by providing computation and caching resources directly to task offloading (TO) users and content request (CR) users. However, existing studies often focus exclusively on either TO users or CR users within EC networks, neglecting the interaction between these two groups. To address this gap, we investigate the offloading and caching decision-making in scenarios where TO and CR users coexist. Furthermore, we employ full-duplex (FD) technology to enhance spectral utilization for edge-end transmissions. Specifically, we jointly optimize offloading and caching in FD-enabled EC networks. To accomplish this, we decompose the formulated optimization problem into three sub-problems using the alternating optimization (AO) method. We then propose a three-subproblem alternating iterative delay minimization algorithm to effectively tackle the challenges of offloading and caching. Additionally, we analyze the convergence and complexity of our proposed algorithm. Finally, we conduct extensive simulations to evaluate the effectiveness of our approach. The simulation results demonstrate that the delay reduction achieved by our algorithm is between 24.78% and 89.23% greater than that of comparative algorithms.

Driven by the increasing demands of vehicular tasks, edge offloading has emerged as a promising paradigm to enhance quality of experience (QoE) in Internet of Vehicles (IoV) networks. This approach enables vehicles to offload computation-intensive tasks to edge servers, resulting in reduced computation delays and lower energy consumption. However, traditional binary offloading limits the efficiency of edge offloading. To address this gap, we propose a partial offloading strategy that jointly optimizes the offloading ratio, computation, and communication resources in IoV. Recognizing the varying priorities of vehicular tasks regarding task delay and energy consumption, we formulate two distinct scenarios: one focused on minimizing delay and the other on minimizing energy consumption. Furthermore, we employ a reinforcement learning approach to establish a multi-dimensional joint optimization function by setting different objectives for each scenario. Based on this framework, we introduce a multi-state iteration deep deterministic policy gradient algorithm (SIDDPG), which effectively determines task partitioning and resource allocation. Simulation results demonstrate that the proposed algorithm outperforms benchmark schemes in terms of task delay and energy consumption.

Adversarial examples can assess the robustness of machine learning models, which has attracted the attention of many researchers to adversarial example generation methods. Transferability and imperceptibility stand out as two crucial metrics for evaluating the quality of adversarial examples. However, achieving a balance between these two indicators poses a formidable challenge. In this paper, we propose a low-frequency guided adversarial attack method (LGA) to generate adversarial examples with strong transferability and good imperceptibility. Specifically, we enhance the transferability of adversarial examples by increasing the diversity of attack algorithms, and introduce the guiding principle and the triplet loss constraint to ensure that the generated adversarial examples are optimized away from the class regions of the clean examples. We find that the low-frequency component in the frequency domain of the image contains the vast majority of the semantic information of the image. Therefore, we constrain the attack perturbations to low-frequency component space to enhance the covert nature while maintaining visual coherence, rendering the adversarial examples more difficult to perceive. We conduct extensive experiments on various models with different network structures and multiple defense strategies, and the experimental results demonstrate that our method outperforms existing methods in the tradeoff between transferability and imperceptibility, achieving the SOTA performance.

In the emerging cloud-edge-end computing networks, edge servers possess more constrained resources and face greater task offloading pressure than centralized cloud servers due to the surge in mobile applications and data. Concurrently, the presence of multiple edge service providers introduces additional challenges, including competition among servers, disordered resource pricing, and a lack of coordination in edge and cloud resource allocation. To address these issues, we propose a novel approach aimed at optimizing task deployment, resource pricing, and system coordination. First, we develop a competitiveness model to facilitate efficient edge-side task allocation while addressing the challenges of resource pricing under competitive conditions. Second, we design a transformer-based task prediction model to enhance the accuracy of resource demand forecasting, thereby enabling more effective edge-cloud resource allocation. To achieve these objectives, the system's interaction is structured into two distinct stages. This division simplifies the problem-solving process and ensures that the long-term goal of maximizing benefits for all stakeholders—edge service providers, cloud providers, and end-users—is achieved. The proposed solution not only improves task offloading efficiency and resource utilization, but also promotes fair competition and pricing transparency across the system.

Fine-tuning Pre-trained Language Models (PLMs) is a popular Natural Language Processing (NLP) paradigm for addressing Named Entity Recognition (NER) tasks. However, neural network models often demonstrate poor generalization capabilities due to significant disparities between the knowledge learned by PLMs and the distribution of the target dataset, as well as data scarcity issues. In addition, token omission in predictions due to insufficient learning remains a challenge in NER. In this paper, we propose a kNN retrieval enhancement algorithm (WkNER) that incorporates word segmentation information to enhance the model’s generalization ability and alleviate the problem of missing entity tokens in prediction. The introduction of word segmentation information is used to preliminarily determine the boundaries of entities and alleviate the common prediction errors of missing tokens within entities made by the fine-tuned model. Secondly, we find that non-entities in the retrieval table contain a large amount of redundant information, and explore the effects of introducing non-entity information of different scales on the model. Experimental results show that our proposed method significantly improves the performance of baseline models, and achieves better or compared recognition accuracy than previous state-of-the-art models in multiple public Chinese and English datasets. Especially in low-resource scenarios, our method achieves higher accuracy on 20% of the dataset than the original method on the full dataset.

Recently, the lightweight single image super-resolution (SISR) model based on information distillation has attracted the attention of many researchers due to its ability to recover high-resolution images quickly. We reassess and delve into the advantages and disadvantages of information distillation structures, and propose an information scaling distillation network (ISDN) for lightweight single image super-resolution, which can accurately and efficiently restore high-resolution images. By optimizing the distillation branch and feature branch of the information distillation, we meticulously designed the stacked block deep scaling distillation block (DSDB) to enlarge the receptive field and increase the network depth. We mainly optimize and design from two aspects. Firstly, we extract redundant information in the distillation branch and integrate it into multiple layers to form deep information transmission. Secondly, we design a blueprint deep scaling residual (BDSR) in the feature branch, which can extract advanced semantic image information, compress and expand feature channels. The qualitative and quantitative results on various benchmark datasets demonstrate the advantages of our model in terms of model parameters, multiply-accumulate operations, test efficiency, and image reconstruction quality. Code is available at https://github.com/ycLi-CV/ISDN-main.

Existing methods for decomposing monolithic applications into microservices in cloud environments primarily rely on the call relationships within itself. However, these methods are difficult to apply directly in resource-constrained and distributed edge network scenarios without considering the heterogeneity of the device. Therefore, this paper proposes a clustering method that ensembles graph structures and device features based on attention mechanism, which utilizes attention encoders to learn node embeddings and employs a spectral clustering algorithm to obtain decomposition results, optimizing the affinity and matching degree between microservices and devices. Experimental results demonstrate that the proposed method exhibits excellent performance in terms of functional independence, modularity, and adaptability of microservices.

In recent years, a number of lightweight single-image super-resolution (SISR) network methods heave been proposed. However, most existing approaches do not make full use of the information before and after the convolution and the high-frequency information of the image. In this paper, we propose a lightweight deep feature aggregation network (DFAnet), which fuses the outputs of all the deep feature aggregation blocks (DFAB) through the designed nonlinear global feature fusion (NGFF) module. The DFAB includes deep feature aggregation structure (DFAS) and non-local sparse attention mechanism (NLSA), where DFAS consists of several aggregation convolutions and information rearrangement operations. Then the output of DFAS is assessed by non-local sparse attention module to form our basic block DFAB. Furthermore, we design a nonlinear global feature fusion (NGFF) module to learn the nonlinear relationship between the output of each DFAB, which encourages every DFAB to pay attention to different patterns of the image. The qualitative and quantitative experimental results on several benchmark datasets show the proposed method achieves the state-of-the-art results in term of reconstruction accuracy, computational complexity and memory consumption.

The rapid development of Internet of Vehicle (IoV) technology has brought the improvement of user experience satisfaction. Subsequently, a variety of vehicle applications put forward higher requirements for information transmission and storage space. A new intelligent edge content caching mechanism is proposed to adapt to the dynamic change of vehicles and differences of storage space of existing facilities. Firstly, based on Long Short Term Memory(LSTM), a resource request prediction model is proposed to effectively estimate the number of content request over a period of time. Then, considering the popularity of the requested content and the preferences of different vehicle users, this paper proposes Dynamic content cache algorithm(DCCA). Among them, the model is built through Markov Decision Process(MDP) to update and optimize the request content using Double Deep Q-Network(DDON). This experiment shows that DCCA is able to improve the hit rate by 50% and reduce the average delay by 20ms in the face of complex and varied request contents with limited cache capacity

Cloud computing and mobile edge computing techniques supply efficient ways to solve the contradiction between the increasing computing and storage demands of portable terminals and the limited capacity. In this paper, we conduct a three-tier hierarchical service system with multiple UEs, multiple MECs, and a single cloud center. It's worth noting that multiple UEs with personalized options generate a large number of different tasks in real time. To deal with this offloading problem, a response ratio offloading strategy (RROS) centered on user preference and real-time nature is designed to make MECs or CC serve as many UEs as possible. Therefore, a MEC-choosing preference list of each UE is created based on its past experiences at first. Then, each MEC iteratively sorts UEs with its ranking in the UEs' preference list. In order to avoid that the first task arriving at MEC occupies too many resources of MEC and cannot achieve global optimization, we also adopt loop iterative sequencing for multiple tasks arriving within a stipulated time. Lastly, by comparing the optimal response ratio on different MECs and CC, multiple MECs and the CC collaborative offload computing tasks of multiple UEs. Experimental results show that the algorithm significantly outperforms conventional techniques.

Abstract Automatic object segmentation has been a challenging task due to intensity inhomogeneity. The traditional way is to eliminate the intensity inhomogeneity, which causes the object to lose useful intensity information. The authors propose an adaptive level set method for the segmentation of intensity inhomogeneous images. Firstly, global and local features are utilised to collaboratively estimate the image, which devotes to compensating for intensity inhomogeneity. The local estimation retains detailed spatial information, and the global estimation mainly contains the regional information of the partitioned object. Then, during the construction of the energy functional, joint estimation is introduced to create the external energy. To acquire the precise location of the boundary, a weighting factor indicated by the gradient is introduced into the internal energy. Finally, after the numerical calculation of the energy functional by additive operator splitting algorithm, this method achieves the desired performance in terms of accuracy and robustness. Experimental results verify this method outperforms the comparative methods and can be applied to many real‐world scenarios.

In recent years, correlation filter based trackers have significantly advanced the state-of-the-art in visual tracking. However, most existing correlation filter based tracking algorithms update target object model assuming that target appearances change smoothly over time. This assumption may not be appropriate for handling more challenging situations such as occlusion, deformation, illumination variation, and abrupt motion, which may break temporal smoothness assumption. To address these issues, in this paper, we propose a novel treestructured correlation filters (TCF) for diverse target object appearance modeling, where multiple correlation filters collaborate to estimate target states and determine the desirable paths for online model updates in the tree. As a result, the proposed TCF tracker has the advantages of both CNNs and correlation filter based trackers. Furthermore, our TCF tracker can preserve model reliability by smoothly updating deep correlation filters along the path in the tree, and make the learned appearance models sufficiently diverse and discriminative. Extensive experimental results on two challenging benchmark datasets demonstrate that the proposed TCF tracking algorithm performs favorably against the state-of-the-art trackers.

The large number of mobile-sensing vehicles traveling in cities offer a novel solution to the collection of vast amounts of multimedia data packets. When a vehicle passes through the data center (DC), the collected multimedia data packets will be transmitted to the DC. Due to the mobile characteristic of vehicular sensor networks, the main challenge lies in how to improve the multimedia data delivery ratio and balance the data packet collections. In this paper, in consideration of delay and delivery factors, a novel routing method is proposed to optimize multimedia data collections in mobile sensing vehicles (DDSVs). This method targets at balancing multimedia data collections, improving the delivery ratio of the multimedia data, and reducing the delay ratio in Internet of Things (IoT) networks. In the DDSV scheme, two rules are designed for improving the collection of multimedia data in the IoT. These rules pertain to: 1) data and 2) vehicular priorities. First, different regions hold different priorities of data packet transmission, which can improve the delivery ratio in the suburban areas and reduce the delay ratio. Meanwhile, this scheme is capable of guaranteeing the balance of multimedia data collection. Second, the vehicular priority is proportional to the probability of a vehicle reaching a DC. Therefore, the data should be forwarded to vehicles with higher priorities, that is, the vehicles which are more likely to pass by the DC. By using these two rules, the DDSV scheme can improve the performances of the multimedia data delivery ratio, compared with the conventional optimal vehicular data forwarding scheme. In the simulation experiments, the DDSV scheme utilizes multidatasets of Beijing city, where the average delay for data collection can be decreased by 17.3% in general, and by 41.8% in the suburban areas; the average data delivery ratio can be improved by 16.9% in comparison to the previous studies.