Reviewerly/exHarmony huggingface dataset:
CBPH-Net: A Small Object Detector for Behavior Recognition in Classroom Scenarios

Recognizing classroom behavior is crucial for assessing and improving teaching quality. However, existing methods for behavior recognition have limited accuracy due to issues such as occlusions, pose variations, and inconsistent target scales. To address these challenges, we propose an advanced single-stage object detector called CBPH-Net. Specifically, we design an efficient Feature Extraction Module (FEM) to capture more channel information and relevant features from the images in the backbone network. The neck network combines the PANet architecture and Coordinate Attention (CA) to integrate semantic and positional information and suppress irrelevant background information, enabling the network to accurately locate students. ConvNeXt Block Prediction Head (CBPH) utilizes convolutional kernels of different sizes and parsing multi-scale features to enhance the multi-scale recognition capability of CBPH-Net especially for accurate detection of small objects. To reduce the influence of irrelevant background, we use elliptical boxes instead of rectangular boxes when calculating the similarity between ground truth and predicted values. In addition, we construct a dataset named STBD-08 that contains 4432 images with 151574 labeled anchors covering 8 typical classroom behaviors. On the proposed dataset STBD-08, CBPH-Net achieves mean average precision (mAP) of 87.5% (an improvement of 3.4% compared to YOLOv5 and 1.2% compared to YOLOv7). It processes one frame with the latency of 31.3ms (1ms slower than YOLOv5 and 5.3ms faster than YOLOv7). Moreover, it achieves a precision of 75.7% in small object recognition, surpassing all comparative methods. The experimental results demonstrate that CBPH-Net can be efficiently applied to classroom behavior recognition tasks. Codes and datasets are available at: https://github.com/icedle/CBPH-Net.
WPO: A Whale Particle Optimization Algorithm

Abstract Metaheuristic algorithms are novel optimization algorithms often inspired by nature. In recent years, scholars have proposed various metaheuristic algorithms, such as the genetic algorithm (GA), artificial bee colony, particle swarm optimization (PSO), crow search algorithm, and whale optimization algorithm (WOA), to solve optimization problems. Among these, PSO is the most commonly used. However, different algorithms have different limitations. For example, PSO is prone to premature convergence and falls into a local optimum, whereas GA coding is difficult and uncertain. Therefore, an algorithm that can increase the computing power and particle diversity can address the limitations of existing algorithms. Therefore, this paper proposes a hybrid algorithm, called whale particle optimization (WPO), that combines the advantages of the WOA and PSO to increase particle diversity and can jump out of the local optimum. The performance of the WPO algorithm was evaluated using four optimization problems: function evaluation, image clustering, permutation flow shop scheduling, and data clustering. The test data were selected from real-life situations. The results demonstrate that the proposed algorithm competes well against existing algorithms.
An efficient hybrid approach for optimization using simulated annealing and grasshopper algorithm for IoT applications

Abstract The multi-objective grasshopper optimization algorithm (MOGOA) is a relatively new algorithm inspired by the collective behavior of grasshoppers, which aims to solve multi-objective optimization problems in IoT applications. In order to enhance its performance and improve global convergence speed, the algorithm integrates simulated annealing (SA). Simulated annealing is a metaheuristic algorithm that is commonly used to improve the search capability of optimization algorithms. In the case of MOGOA, simulated annealing is integrated by employing symmetric perturbation to control the movement of grasshoppers. This helps in effectively balancing exploration and exploitation, leading to better convergence and improved performance. The paper proposes two hybrid algorithms based on MOGOA, which utilize simulated annealing for solving multi-objective optimization problems. One of these hybrid algorithms combines chaotic maps with simulated annealing and MOGOA. The purpose of incorporating simulated annealing and chaotic maps is to address the issue of slow convergence and enhance exploitation by searching high-quality regions identified by MOGOA. Experimental evaluations were conducted on thirteen different benchmark functions to assess the performance of the proposed algorithms. The results demonstrated that the introduction of simulated annealing significantly improved the convergence of MOGOA. Specifically, the IDG (Inverse Distance Generational distance) values for benchmark functions ZDT1, ZDT2, and ZDT3 were smaller than the IDG values obtained by using MOGOA alone, indicating better performance in terms of convergence. Overall, the proposed algorithms exhibit promise in solving multi-objective optimization problems.
Explainable machine learning for phishing feature detection

Abstract Phishing is a very dangerous security threat that affects individuals as well as companies and organizations. To fight the risks associated with this threat, it is important to detect phishing websites in a timely manner. Machine learning models work well for this purpose as they can predict phishing cases, using information on the underlying websites. In this paper, we contribute to the research on the detection of phishing websites by proposing an explainable machine learning model that can provide not only accurate predictions of phishing, but also explanations of which features are most likely associated with phishing websites. To this aim, we propose a novel feature selection model based on Lorenz Zonoids, the multidimensional extension of Gini coefficient. We illustrate our proposal on a real dataset that contains features of both phishing and legitimate websites.
Context and detail interaction network for stereo rain streak and raindrop removal

Recently stereo image deraining has attracted lots of attention due to its superiority of abundant information from cross views. Exploring interaction information across stereo views is the key to improving the performance of stereo image deraining. In this paper, we design a general coarse-to-fine deraining framework for stereo rain streak and raindrop removal, called CDINet, comprising a stereo rain removal subnet and a stereo detail recovery subnet to restore images progressively. Two types of interaction modules are devised to explore interaction information for rain removal and detail recovery, respectively. Specifically, a global context interaction module is proposed to learn long-range dependencies of stereo images and remove rain by utilizing stereo structural information. A local detail interaction module is designed to model local contextual correlation, which aims at restoring the detail information by using neighborhood information from cross views. Extensive experiments are conducted on the two datasets including a synthetic rain streak removal dataset (RainKITTI) and a real raindrop removal dataset (Stereo Waterdrop), which demonstrates that our method sets new state-of-the-art deraining performance in terms of both quantitative and qualitative metrics with faster speed.
Anomaly detection in streaming data: A comparison and evaluation study

The detection of anomalies in streaming data faces complexities that make traditional static methods unsuitable due to computational costs and nonstationarity. We test and evaluate eight state of the art algorithms against prominent challenges related to streaming data. Results show insights regarding accuracy, memory-dependency, parameterization, and pre-knowledge exploitation, thus revealing the high impact of some data characteristics to establish a most appropriate algorithm—namely: locality (i.e., whether outlierness is relative to local contexts), relativeness (i.e., if past data defines outlierness), and concept drift (if it is expected, its intensity and frequency). In most applied cases, such factors can be inferred in advance through the use of historical data and domain knowledge. Assuming the viability of the studied methods in terms of time efficiency, this work discloses key findings to achieve optimal designs of streaming data anomaly detection in real-life applications.
Progressive convolutional transformer for image restoration

In the past few years, convolutional neural networks (CNNs) have become the primary workhorse for image restoration tasks. However, the deficiency of modeling long-range dependencies due to the local computational property of convolution greatly limits the restoration performance. To overcome this limitation, we propose a novel multi-stage progressive convolutional Transformer to recursively restore the degraded images, termed PCformer, which enjoys a high capability for capturing local context and global dependencies with friendly computational cost. Specifically, each stage of PCformer is an asymmetric encoder–decoder network whose bottleneck is built upon a tailored Transformer block with convolution operation deployed to avoid any loss of local context. Both encoder and decoder are convolution-based modules, thus allowing to explore rich contextualized information for image recovery. Taking the low-resolution features encoded by the encoder as tokens input into the Transformer bottleneck guarantees that long-range pixel interactions are captured while reducing the computational burden. Meanwhile, we apply a gated module for filtering redundant information propagation between every two phases. In addition, long-range enhanced inpainting is further introduced to mining the ability of PCformer to exploit distant complementary features. Extensive experiments yield superior results and in particular establishing new state-of-the-art results on several image restoration tasks, including deraining (+0.37 dB on Rain13K), denoising (+0.11 dB on DND), dehazing (+0.56 dB on I-HAZE), enhancement (+0.72 dB on SICE), and shadow removal (+0.65 RMSE on ISTD). The implementation code is available at https://github.com/Jeasco/PCformer.
Always Strengthen Your Strengths: A Drift-Aware Incremental Learning Framework for CTR Prediction

CTR prediction is crucial in recommendation systems and online advertising platforms, where user-generated data streams that drift over time can lead to catastrophic forgetting if the model continuously adapts to new data distribution. Conventional strategies for catastrophic forgetting are challenging to deploy due to memory constraints and diverse data distributions. To address this, we propose a novel drift-aware incremental learning framework based on ensemble learning for CTR prediction, which uses explicit error-based drift detection on streaming data to strengthen well-adapted ensembles and freeze ensembles that do not match the input distribution, avoiding catastrophic interference. Our method outperforms all baselines considered in offline experiments and A/B tests.
PLATE: A Prompt-Enhanced Paradigm for Multi-Scenario Recommendations

With the explosive growth of commercial applications of recommender systems, multi-scenario recommendation (MSR) has attracted considerable attention, which utilizes data from multiple domains to improve their recommendation performance simultaneously. However, training a unified deep recommender system (DRS) may not explicitly comprehend the commonality and difference among domains, whereas training an individual model for each domain neglects the global information and incurs high computation costs. Likewise, fine-tuning on each domain is inefficient, and recent advances that apply the prompt tuning technique to improve fine-tuning efficiency rely solely on large-sized transformers. In this work, we propose a novel prompt-enhanced paradigm for multi-scenario recommendation. Specifically, a unified DRS backbone model is first pre-trained using data from all the domains in order to capture the commonality across domains. Then, we conduct prompt tuning with two novel prompt modules, capturing the distinctions among various domains and users. Our experiments on Douban, Amazon, and Ali-CCP datasets demonstrate the effectiveness of the proposed paradigm with two noticeable strengths: (i) its great compatibility with various DRS backbone models, and (ii) its high computation and storage efficiency with only 6% trainable parameters in prompt tuning phase. The implementation code is available for easy reproduction.
Diffusion Recommender Model

Generative models such as Generative Adversarial Networks (GANs) and Variational Auto-Encoders (VAEs) are widely utilized to model the generative process of user interactions. However, they suffer from intrinsic limitations such as the instability of GANs and the restricted representation ability of VAEs. Such limitations hinder the accurate modeling of the complex user interaction generation procedure, such as noisy interactions caused by various interference factors. In light of the impressive advantages of Diffusion Models (DMs) over traditional generative models in image synthesis, we propose a novel Diffusion Recommender Model (named DiffRec) to learn the generative process in a denoising manner. To retain personalized information in user interactions, DiffRec reduces the added noises and avoids corrupting users' interactions into pure noises like in image synthesis. In addition, we extend traditional DMs to tackle the unique challenges in recommendation: high resource costs for large-scale item prediction and temporal shifts of user preference. To this end, we propose two extensions of DiffRec: L-DiffRec clusters items for dimension compression and conducts the diffusion processes in the latent space; and T-DiffRec reweights user interactions based on the interaction timestamps to encode temporal information. We conduct extensive experiments on three datasets under multiple settings (e.g., clean training, noisy training, and temporal training). The empirical results validate the superiority of DiffRec with two extensions over competitive baselines.
Leveraging Transferable Knowledge Concept Graph Embedding for Cold-Start Cognitive Diagnosis

Cognitive diagnosis (CD) aims to reveal the proficiency of students on specific knowledge concepts and traits of test exercises (e.g., difficulty). It plays a critical role in intelligent education systems by supporting personalized learning guidance. However, recent developments in CD mostly concentrate on improving the accuracy of diagnostic results and often overlook the important and practical task: domain-level zero-shot cognitive diagnosis (DZCD). The primary challenge of DZCD is the deficiency of student behavior data in the target domain due to the absence of student-exercise interactions or unavailability of exercising records for training purposes. To tackle the cold-start issue, we propose a two-stage solution named TechCD (Transferable knowledgE Concept grapH embedding framework for Cognitive Diagnosis). The fundamental notion involves utilizing a pedagogical knowledge concept graph (KCG) as a mediator to connect disparate domains, allowing the transmission of student cognitive signals from established domains to the zero-shot cold-start domain. Specifically, a naive yet effective graph convolutional network (GCN) with the bottom-layer discarding operation is initially employed over the KCG to learn transferable student cognitive states and domain-specific exercise traits. Moreover, we give three implementations of the general TechCD framework following the typical cognitive diagnosis solutions. Finally, extensive experiments on real-world datasets not only prove that Tech can effectively perform zero-shot diagnosis, but also give some popular applications such as exercise recommendation.
Take a Fresh Look at Recommender Systems from an Evaluation Standpoint

Recommendation has become a prominent area of research in the field of Information Retrieval (IR). Evaluation is also a traditional research topic in this community. Motivated by a few counter-intuitive observations reported in recent studies, this perspectives paper takes a fresh look at recommender systems from an evaluation standpoint. Rather than examining metrics like recall, hit rate, or NDCG, or perspectives like novelty and diversity, the key focus here is on how these metrics are calculated when evaluating a recommender algorithm. Specifically, the commonly used train/test data splits and their consequences are re-examined. We begin by examining common data splitting methods, such as random split or leave-one-out, and discuss why the popularity baseline is poorly defined under such splits. We then move on to explore the two implications of neglecting a global timeline during evaluation: data leakage and oversimplification of user preference modeling. Afterwards, we present new perspectives on recommender systems, including techniques for evaluating algorithm performance that more accurately reflect real-world scenarios, and possible approaches to consider decision contexts in user preference modeling.
Topic-oriented Adversarial Attacks against Black-box Neural Ranking Models

Neural ranking models (NRMs) have attracted considerable attention in information retrieval. Unfortunately, NRMs may inherit the adversarial vulnerabilities of general neural networks, which might be leveraged by black-hat search engine optimization practitioners. Recently, adversarial attacks against NRMs have been explored in the paired attack setting, generating an adversarial perturbation to a target document for a specific query. In this paper, we focus on a more general type of perturbation and introduce the topic-oriented adversarial ranking attack task against NRMs, which aims to find an imperceptible perturbation that can promote a target document in ranking for a group of queries with the same topic. We define both static and dynamic settings for the task and focus on decision-based black-box attacks. We propose a novel framework to improve topic-oriented attack performance based on a surrogate ranking model. The attack problem is formalized as a Markov decision process (MDP) and addressed using reinforcement learning. Specifically, a topic-oriented reward function guides the policy to find a successful adversarial example that can be promoted in rankings to as many queries as possible in a group. Experimental results demonstrate that the proposed framework can significantly outperform existing attack strategies, and we conclude by re-iterating that there exist potential risks for applying NRMs in the real world.
Can Generative LLMs Create Query Variants for Test Collections? An Exploratory Study

This paper explores the utility of a Large Language Model (LLM) to automatically generate queries and query variants from a description of an information need. Given a set of information needs described as backstories, we explore how similar the queries generated by the LLM are to those generated by humans. We quantify the similarity using different metrics and examine how the use of each set would contribute to document pooling when building test collections. Our results show potential in using LLMs to generate query variants. While they may not fully capture the wide variety of human-generated variants, they generate similar sets of relevant documents, reaching up to 71.1% overlap at a pool depth of 100.
Quantifying Ranker Coverage of Different Query Subspaces

The information retrieval community has observed significant performance improvements over various tasks due to the introduction of neural architectures. However, such improvements do not necessarily seem to have happened uniformly across a range of queries. As we will empirically show in this paper, the performance of neural rankers follow a long-tail distribution where there are many subsets of queries, which are not effectively satisfied by neural methods. Despite this observation, performance is often reported using standard retrieval metrics, such as MRR or nDCG, which capture average performance over all queries. As such, it is not clear whether reported improvements are due to incremental boost on a small subset of already well-performing queries or addressing queries that have been difficult to address by existing methods. In this paper, we propose the Task Subspace Coverage (TaSC /tAHsk/) metric, which systematically quantifies whether and to what extent improvements in retrieval effectiveness happen on similar or disparate query subspaces for different rankers. Our experiments show that the consideration of our proposed TaSC metric in conjunction with existing ranking metrics provides deeper insight into ranker performance and their contribution to overall advances on a given task.
Federated domain generalization with global robust model aggregation strategy for bearing fault diagnosis

Abstract Federated learning ensures the privacy of fault diagnosis by maintaining a decentralized and local training data approach, eliminating the need to share confidential information with a central server. However, the performance of trained models tends to significantly deteriorate when applied to completely unseen domains. To address this challenge, this paper introduces a novel method called federated domain generalization with a global robust model aggregation strategy. Our proposed method can collaboratively train a model with outstanding generalization ability and robustness to unseen target domains in a data-protecting way. Specifically, a maximum mean discrepancy is introduced in the central server to reduce the discrepancy of features from different source clients. Meanwhile, classification loss across source domains is designed as the weights for local model aggregation in the central server. Finally, experimental results under two different bearing fault datasets show that our method obtains higher classification accuracy than other compared methods, which demonstrates that the proposed method has better generalization ability and is promising in real industrial applications.
Scalable wavelength-multiplexing photonic reservoir computing

Photonic reservoir computing (PRC) is a special hardware recurrent neural network, which is featured with fast training speed and low training cost. This work shows a wavelength-multiplexing PRC architecture, taking advantage of the numerous longitudinal modes in a Fabry–Perot (FP) semiconductor laser. These modes construct connected physical neurons in parallel, while an optical feedback loop provides interactive virtual neurons in series. We experimentally demonstrate a four-channel wavelength-multiplexing PRC architecture with a total of 80 neurons. The clock rate of the multiplexing PRC reaches as high as 1.0 GHz, which is four times higher than that of the single-channel case. In addition, it is proved that the multiplexing PRC exhibits a superior performance on the task of signal equalization in an optical fiber communication link. This improved performance is owing to the rich neuron interconnections both in parallel and in series. In particular, this scheme is highly scalable owing to the rich mode resources in FP lasers.