Central Region
BERT4Traj: Transformer Based Trajectory Reconstruction for Sparse Mobility Data
Yang, Hao, Yao, Angela, Whalen, Christopher, Mai, Gengchen
Understanding human mobility is essential for applications in public health, transportation, and urban planning. However, mobility data often suffers from sparsity due to limitations in data collection methods, such as infrequent GPS sampling or call detail record (CDR) data that only capture locations during communication events. To address this challenge, we propose BERT4Traj, a transformer-based model that reconstructs complete mobility trajectories by predicting hidden visits in sparse movement sequences. Inspired by BERT's masked language modeling objective and self-attention mechanisms, BERT4Traj leverages spatial embeddings, temporal embeddings, and contextual background features such as demographics and anchor points. We evaluate BERT4Traj on real-world CDR and GPS datasets collected in Kampala, Uganda, demonstrating that our approach significantly outperforms traditional models such as Markov Chains, KNN, RNNs, and LSTMs. Our results show that BERT4Traj effectively reconstructs detailed and continuous mobility trajectories, enhancing insights into human movement patterns.
An Enhanced YOLOv8 Model for Real-Time and Accurate Pothole Detection and Measurement
Yurdakul, Mustafa, Tasdemir, Şakir
Selçuk University, Computer Engineering Department, Konya, Turkey, stasdemir@selcuk .edu.tr, https://orcid.org/0000 - 0002 - 2433 - 246X Abstract: Potholes cause vehicle damage and traffic accidents, creating serious safety and economic problems. Therefore, early and accurate detection of potholes is crucial. Existing detection methods are usually only based on 2D RGB images and cannot accurately analyze the physical characteristics of potholes. In this paper, a publicly available dataset of RGB - D images (PothRGBD) is created and an impr oved YOLOv8 - based model is proposed for both pothole detection and pothole physical features analysis. The Intel RealSense D415 depth camera was used to collect RGB and depth data from the road surfaces, resulting in a PothRGBD dataset of 1000 images. The data was labeled in YOLO format suitable for segmentation. A novel YOLO model is proposed based on the YOLOv8n - seg architecture, which is structurally improved with Dynamic Snake Convolution (DSConv), Simple Attention Module (SimAM) and Gaussian Error Lin ear Unit (GELU). The proposed model segmented potholes with irregular edge structure more accurately, and performed perimeter and depth measurements on depth maps with high accuracy. With the proposed model, the values increased to 93.7%, 90.4% and 93.8% respectively. Thus, an improvement of 1.96% in precision, 6.13% in recall and 2.07% in mAP was achieved. The proposed model performs pothole detection as well as perimet er and depth measurement with high accuracy and is suitable for real - time applications due to its low model complexity. In this way, a lightweight and effective model that can be used in deep learning - based intelligent transportation solutions has been acq uired. Pothole Detection, YOLOv8 Segmentation, Depth Estimation, Intelligent Transportation Systems, RGB - D Imaging, Deep Learning 1. Introduction Potholes are one of the most common and dangerous types of road surface deterioration. It usually oc curs when water seeps into the asphalt or concrete surface and weakens the sub - layers, then the traffic load erodes the weakened area [1, 2] . Over time, small cracks widen into deep potholes.
Deep Learning-Based Transfer Learning for Classification of Cassava Disease
Junior, Ademir G. Costa, da Silva, Fábio S., Rios, Ricardo
This paper presents a performance comparison among four Convolutional Neural Network architectures (EfficientNet-B3, InceptionV3, ResNet50, and VGG16) for classifying cassava disease images. The images were sourced from an imbalanced dataset from a competition. Appropriate metrics were employed to address class imbalance. The results indicate that EfficientNet-B3 achieved on this task accuracy of 87.7%, precision of 87.8%, revocation of 87.8% and F1-Score of 87.7%. These findings suggest that EfficientNet-B3 could be a valuable tool to support Digital Agriculture.
Treatment Non-Adherence Bias in Clinical Machine Learning: A Real-World Study on Hypertension Medication
Liang, Zhongyuan, Suresh, Arvind, Chen, Irene Y.
Machine learning systems trained on electronic health records (EHRs) increasingly guide treatment decisions, but their reliability depends on the critical assumption that patients follow the prescribed treatments recorded in EHRs. Using EHR data from 3,623 hypertension patients, we investigate how treatment non-adherence introduces implicit bias that can fundamentally distort both causal inference and predictive modeling. By extracting patient adherence information from clinical notes using a large language model, we identify 786 patients (21.7%) with medication non-adherence. We further uncover key demographic and clinical factors associated with non-adherence, as well as patient-reported reasons including side effects and difficulties obtaining refills. Our findings demonstrate that this implicit bias can not only reverse estimated treatment effects, but also degrade model performance by up to 5% while disproportionately affecting vulnerable populations by exacerbating disparities in decision outcomes and model error rates. This highlights the importance of accounting for treatment non-adherence in developing responsible and equitable clinical machine learning systems.
INJONGO: A Multicultural Intent Detection and Slot-filling Dataset for 16 African Languages
Yu, Hao, Alabi, Jesujoba O., Bukula, Andiswa, Zhuang, Jian Yun, Lee, En-Shiun Annie, Guge, Tadesse Kebede, Azime, Israel Abebe, Buzaaba, Happy, Sibanda, Blessing Kudzaishe, Kalipe, Godson K., Mukiibi, Jonathan, Kabenamualu, Salomon Kabongo, Setaka, Mmasibidi, Ndolela, Lolwethu, Odu, Nkiruka, Mabuya, Rooweither, Muhammad, Shamsuddeen Hassan, Osei, Salomey, Samb, Sokhar, Murage, Juliet W., Klakow, Dietrich, Adelani, David Ifeoluwa
Slot-filling and intent detection are well-established tasks in Conversational AI. However, current large-scale benchmarks for these tasks often exclude evaluations of low-resource languages and rely on translations from English benchmarks, thereby predominantly reflecting Western-centric concepts. In this paper, we introduce Injongo -- a multicultural, open-source benchmark dataset for 16 African languages with utterances generated by native speakers across diverse domains, including banking, travel, home, and dining. Through extensive experiments, we benchmark the fine-tuning multilingual transformer models and the prompting large language models (LLMs), and show the advantage of leveraging African-cultural utterances over Western-centric utterances for improving cross-lingual transfer from the English language. Experimental results reveal that current LLMs struggle with the slot-filling task, with GPT-4o achieving an average performance of 26 F1-score. In contrast, intent detection performance is notably better, with an average accuracy of 70.6%, though it still falls behind the fine-tuning baselines. Compared to the English language, GPT-4o and fine-tuning baselines perform similarly on intent detection, achieving an accuracy of approximately 81%. Our findings suggest that the performance of LLMs is still behind for many low-resource African languages, and more work is needed to further improve their downstream performance.
Leaf diseases detection using deep learning methods
This study, our main topic is to devlop a new deep-learning approachs for plant leaf disease identification and detection using leaf image datasets. We also discussed the challenges facing current methods of leaf disease detection and how deep learning may be used to overcome these challenges and enhance the accuracy of disease detection. Therefore, we have proposed a novel method for the detection of various leaf diseases in crops, along with the identification and description of an efficient network architecture that encompasses hyperparameters and optimization methods. The effectiveness of different architectures was compared and evaluated to see the best architecture configuration and to create an effective model that can quickly detect leaf disease. In addition to the work done on pre-trained models, we proposed a new model based on CNN, which provides an efficient method for identifying and detecting plant leaf disease. Furthermore, we evaluated the efficacy of our model and compared the results to those of some pre-trained state-of-the-art architectures.
Nteasee: A mixed methods study of expert and general population perspectives on deploying AI for health in African countries
Asiedu, Mercy Nyamewaa, Haykel, Iskandar, Dieng, Awa, Kauer, Kerrie, Ahmed, Tousif, Ofori, Florence, Chan, Charisma, Pfohl, Stephen, Rostamzadeh, Negar, Heller, Katherine
Artificial Intelligence (AI) for health has the potential to significantly change and improve healthcare. However in most African countries, identifying culturally and contextually attuned approaches for deploying these solutions is not well understood. To bridge this gap, we conduct a qualitative study to investigate the best practices, fairness indicators, and potential biases to mitigate when deploying AI for health in African countries, as well as explore opportunities where artificial intelligence could make a positive impact in health. We used a mixed methods approach combining in-depth interviews (IDIs) and surveys. We conduct 1.5-2 hour long IDIs with 50 experts in health, policy, and AI across 17 countries, and through an inductive approach we conduct a qualitative thematic analysis on expert IDI responses. We administer a blinded 30-minute survey with case studies to 672 general population participants across 5 countries in Africa and analyze responses on quantitative scales, statistically comparing responses by country, age, gender, and level of familiarity with AI. We thematically summarize open-ended responses from surveys. Our results find generally positive attitudes, high levels of trust, accompanied by moderate levels of concern among general population participants for AI usage for health in Africa. This contrasts with expert responses, where major themes revolved around trust/mistrust, ethical concerns, and systemic barriers to integration, among others. This work presents the first-of-its-kind qualitative research study of the potential of AI for health in Africa from an algorithmic fairness angle, with perspectives from both experts and the general population. We hope that this work guides policymakers and drives home the need for further research and the inclusion of general population perspectives in decision-making around AI usage.
LM-PUB-QUIZ: A Comprehensive Framework for Zero-Shot Evaluation of Relational Knowledge in Language Models
Ploner, Max, Wiland, Jacek, Pohl, Sebastian, Akbik, Alan
Knowledge probing evaluates the extent to which a language model (LM) has acquired relational knowledge during its pre-training phase. It provides a cost-effective means of comparing LMs of different sizes and training setups and is useful for monitoring knowledge gained or lost during continual learning (CL). In prior work, we presented an improved knowledge probe called BEAR (Wiland et al., 2024), which enables the comparison of LMs trained with different pre-training objectives (causal and masked LMs) and addresses issues of skewed distributions in previous probes to deliver a more unbiased reading of LM knowledge. With this paper, we present LM-PUB- QUIZ, a Python framework and leaderboard built around the BEAR probing mechanism that enables researchers and practitioners to apply it in their work. It provides options for standalone evaluation and direct integration into the widely-used training pipeline of the Hugging Face TRANSFORMERS library. Further, it provides a fine-grained analysis of different knowledge types to assist users in better understanding the knowledge in each evaluated LM. We publicly release LM-PUB-QUIZ as an open-source project.
Artificial Intelligence for Public Health Surveillance in Africa: Applications and Opportunities
Tshimula, Jean Marie, Kalengayi, Mitterrand, Makenga, Dieumerci, Lilonge, Dorcas, Asumani, Marius, Madiya, Déborah, Kalonji, Élie Nkuba, Kanda, Hugues, Galekwa, René Manassé, Kumbu, Josias, Mikese, Hardy, Tshimula, Grace, Muabila, Jean Tshibangu, Mayemba, Christian N., Nkashama, D'Jeff K., Kalala, Kalonji, Ataky, Steve, Basele, Tighana Wenge, Didier, Mbuyi Mukendi, Kasereka, Selain K., Dialufuma, Maximilien V., Kumwita, Godwill Ilunga Wa, Muyuku, Lionel, Kimpesa, Jean-Paul, Muteba, Dominique, Abedi, Aaron Aruna, Ntobo, Lambert Mukendi, Bundutidi, Gloria M., Mashinda, Désiré Kulimba, Mpinga, Emmanuel Kabengele, Kasoro, Nathanaël M.
Artificial Intelligence (AI) is revolutionizing various fields, including public health surveillance. In Africa, where health systems frequently encounter challenges such as limited resources, inadequate infrastructure, failed health information systems and a shortage of skilled health professionals, AI offers a transformative opportunity. This paper investigates the applications of AI in public health surveillance across the continent, presenting successful case studies and examining the benefits, opportunities, and challenges of implementing AI technologies in African healthcare settings. Our paper highlights AI's potential to enhance disease monitoring and health outcomes, and support effective public health interventions. The findings presented in the paper demonstrate that AI can significantly improve the accuracy and timeliness of disease detection and prediction, optimize resource allocation, and facilitate targeted public health strategies. Additionally, our paper identified key barriers to the widespread adoption of AI in African public health systems and proposed actionable recommendations to overcome these challenges.
Return of EM: Entity-driven Answer Set Expansion for QA Evaluation
Lee, Dongryeol, Lee, Minwoo, Min, Kyungmin, Park, Joonsuk, Jung, Kyomin
Recently, directly using large language models (LLMs) has been shown to be the most reliable method to evaluate QA models. However, it suffers from limited interpretability, high cost, and environmental harm. To address these, we propose to use soft exact match (EM) with entitydriven answer set expansion. Our approach expands the gold answer set to include diverse surface forms, based on the observation that the surface forms often follow particular patterns depending on the entity type. The experimental results show that our method outperforms traditional evaluation methods by a large margin. Moreover, the reliability of our evaluation method is comparable to that of LLM-based ones, while offering the benefits of high interpretability and reduced environmental harm.