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11 pages, 2136 KiB  
Article
Natural Language Processing-Based Deep Learning to Predict the Loss of Consciousness Event Using Emergency Department Text Records
by Hang A. Park, Inyeop Jeon, Seung-Ho Shin, Soo Young Seo, Jae Jun Lee, Chulho Kim and Ju Ok Park
Appl. Sci. 2024, 14(23), 11399; https://doi.org/10.3390/app142311399 - 6 Dec 2024
Viewed by 767
Abstract
The increasing adoption of electronic medical records (EMRs) presents a unique opportunity to enhance trauma care through data-driven insights. However, extracting meaningful and actionable information from unstructured clinical text remains a significant challenge. Addressing this gap, this study focuses on the application of [...] Read more.
The increasing adoption of electronic medical records (EMRs) presents a unique opportunity to enhance trauma care through data-driven insights. However, extracting meaningful and actionable information from unstructured clinical text remains a significant challenge. Addressing this gap, this study focuses on the application of natural language processing (NLP) techniques to extract injury-related variables and classify trauma patients based on the presence of loss of consciousness (LOC). A dataset of 23,308 trauma patient EMRs, including pre-diagnosis and post-diagnosis free-text notes, was analyzed using a bilingual (English and Korean) pre-trained RoBERTa model. The patients were categorized into four groups based on the presence of LOC and head trauma. To address class imbalance in LOC labeling, deep learning models were trained with weighted loss functions, achieving a high area under the curve (AUC) of 0.91. Local Interpretable Model-agnostic Explanations analysis further demonstrated the model’s ability to identify critical terms related to head injuries and consciousness. NLP can effectively identify LOC in trauma patients’ EMRs, with weighted loss functions addressing data imbalances. These findings can inform the development of AI tools to improve trauma care and decision-making. Full article
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<p>The architecture of the fine-tuned RoBERTa classification model. The model architecture is based on the basic RoBERTa framework. The tokenized input data consists of two types of clinical diagnostic notes: pre-diagnostic notes and post-diagnostic notes, with each note separated by the [SEP] special token. The output from the model is a set of probabilities and values that are calculated using the softmax function.</p>
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<p>Multiclass confusion matrix for test dataset. The number in each cell represents the degree of agreement between the actual and predicted classification groups. The number in round brackets indicates the recall and precision score calculated for each class in the sequence.</p>
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<p>Evaluation of the performance of LOC classification among NLP-based models using different clinical diagnosis notes. (<b>a</b>) Model performance evaluated in the test dataset. The left panel showed a difference in classification performance according to types of clinical notes. The performance improvement for unbalanced data using the weighted loss function is shown in the right panel. The results of the analysis performed on the training dataset are displayed in (<b>b</b>). Points in the scatter plot indicate last updated model performance according to the early stop method.</p>
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<p>Interpretation of LOC classification and the importance of each word feature (English version). The figures indicate the importance of each word in the LOC classification for patients classified as C2 (<b>A</b>) and C3 (<b>B</b>). The right panel displays descriptive input consisting of pre- and post-diagnosis notes. The left panel of each figure shows the weight of features for visualization.</p>
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11 pages, 434 KiB  
Article
Urban and Rural Differences in the Efficacy of a Mobile Health Depression Treatment for Young Adults
by Jeremy Mennis, J. Douglas Coatsworth, Michael Russell, Nikola Zaharakis, Aaron R. Brown and Michael J. Mason
Int. J. Environ. Res. Public Health 2024, 21(12), 1572; https://doi.org/10.3390/ijerph21121572 - 26 Nov 2024
Viewed by 679
Abstract
Depression among young adults represents a growing health problem in the U.S., but access to effective treatment remains a challenge. Mobile health (mHealth) approaches promise to deliver accessible and effective depression treatment; however, questions remain regarding how mHealth depression treatment efficacy may vary [...] Read more.
Depression among young adults represents a growing health problem in the U.S., but access to effective treatment remains a challenge. Mobile health (mHealth) approaches promise to deliver accessible and effective depression treatment; however, questions remain regarding how mHealth depression treatment efficacy may vary geographically based on urban and rural environmental contexts. The present study addresses this knowledge gap by leveraging data from a randomized clinical trial of an mHealth depression treatment called Cognitive Behavioral Therapy-text (CBT-txt) as applied to a sample of 103 U.S. young adults (ages 18–25). Prior research has demonstrated the efficacy of CBT-txt to reduce depressive symptoms. In the present study, we conduct an exploratory, post hoc analysis employing moderated growth curve modeling to investigate whether observed treatment efficacy differed between study participants residing in rural versus urban areas. The findings indicate that CBT-txt treatment effects in terms of reducing depression symptoms were significantly stronger for young adults residing in rural, as compared to urban, regions (β = 13.759, 95% CI = 0.796, 26.723, p < 0.038). We speculate that this is because of the lack of mental healthcare resources in rural, as compared to urban areas, as well as the greater level of environmental stressors, such as artificial light and noise, found in cities, which may mitigate treatment effects. Full article
(This article belongs to the Section Environmental Health)
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<p>Estimated marginal means (solid lines) from growth models of depression symptoms. Graphs depict trajectories over baseline (0), one-month (1), two-month (2), and three-month (3) timepoints for the treatment (orange) and control (blue) groups, with 95% confidence intervals shown (dashed lines). Separate panels show slopes estimated participants residing in urban (<b>left</b>) and rural (<b>right</b>) areas.</p>
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14 pages, 1168 KiB  
Article
CLIP-Llama: A New Approach for Scene Text Recognition with a Pre-Trained Vision-Language Model and a Pre-Trained Language Model
by Xiaoqing Zhao, Miaomiao Xu, Wushour Silamu and Yanbing Li
Sensors 2024, 24(22), 7371; https://doi.org/10.3390/s24227371 - 19 Nov 2024
Viewed by 1056
Abstract
This study focuses on Scene Text Recognition (STR), which plays a crucial role in various applications of artificial intelligence such as image retrieval, office automation, and intelligent transportation systems. Currently, pre-trained vision-language models have become the foundation for various downstream tasks. CLIP exhibits [...] Read more.
This study focuses on Scene Text Recognition (STR), which plays a crucial role in various applications of artificial intelligence such as image retrieval, office automation, and intelligent transportation systems. Currently, pre-trained vision-language models have become the foundation for various downstream tasks. CLIP exhibits robustness in recognizing both regular (horizontal) and irregular (rotated, curved, blurred, or occluded) text in natural images. As research in scene text recognition requires substantial linguistic knowledge, we introduce the pre-trained vision-language model CLIP and the pre-trained language model Llama. Our approach builds upon CLIP’s image and text encoders, featuring two encoder–decoder branches: one visual branch and one cross-modal branch. The visual branch provides initial predictions based on image features, while the cross-modal branch refines these predictions by addressing the differences between image features and textual semantics. We incorporate the large language model Llama2-7B in the cross-modal branch to assist in correcting erroneous predictions generated by the decoder. To fully leverage the potential of both branches, we employ a dual prediction and refinement decoding scheme during inference, resulting in improved accuracy. Experimental results demonstrate that CLIP-Llama achieves state-of-the-art performance on 11 STR benchmark tests, showcasing its robust capabilities. We firmly believe that CLIP-Llama lays a solid and straightforward foundation for future research in scene text recognition based on vision-language models. Full article
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<p>The overall framework of CLIP-Llama. It comprises a visual branch and a cross-modal branch. The cross-modal branch refines and corrects the predictions from the visual branch to produce the final output.</p>
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<p>Encoder framework.</p>
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<p>Decoder framework.</p>
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<p>Decoder framework.</p>
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<p>Part of the dataset images.</p>
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<p>The model’s text recognition results.</p>
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12 pages, 621 KiB  
Systematic Review
Systematic Review of AI-Assisted MRI in Prostate Cancer Diagnosis: Enhancing Accuracy Through Second Opinion Tools
by Saeed Alqahtani
Diagnostics 2024, 14(22), 2576; https://doi.org/10.3390/diagnostics14222576 - 15 Nov 2024
Viewed by 1415
Abstract
Background: Prostate cancer is a leading cause of cancer-related deaths in men worldwide, making accurate diagnosis critical for effective treatment. Recent advancements in artificial intelligence (AI) and machine learning (ML) have shown promise in improving the diagnostic accuracy of prostate cancer. Objectives: This [...] Read more.
Background: Prostate cancer is a leading cause of cancer-related deaths in men worldwide, making accurate diagnosis critical for effective treatment. Recent advancements in artificial intelligence (AI) and machine learning (ML) have shown promise in improving the diagnostic accuracy of prostate cancer. Objectives: This systematic review aims to evaluate the effectiveness of AI-based tools in diagnosing prostate cancer using MRI, with a focus on accuracy, specificity, sensitivity, and clinical utility compared to conventional diagnostic methods. Methods: A comprehensive search was conducted across PubMed, Embase, Ovid MEDLINE, Web of Science, Cochrane Library, and Institute of Electrical and Electronics Engineers (IEEE) Xplore for studies published between 2019 and 2024. Inclusion criteria focused on full-text, English-language studies involving AI for Magnetic Resonance Imaging (MRI) -based prostate cancer diagnosis. Diagnostic performance metrics such as area under curve (AUC), sensitivity, and specificity were analyzed, with risk of bias assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Results: Seven studies met the inclusion criteria, employing various AI techniques, including deep learning and machine learning. These studies reported improved diagnostic accuracy (with AUC scores of up to 97%) and moderate sensitivity, with performance varying based on training data quality and lesion characteristics like Prostate Imaging Reporting and Data System (PI-RADS) scores. Conclusions: AI has significant potential to enhance prostate cancer diagnosis, particularly when used for second opinions in MRI interpretations. While these results are promising, further validation in diverse populations and clinical settings is necessary to fully integrate AI into standard practice. Full article
(This article belongs to the Section Machine Learning and Artificial Intelligence in Diagnostics)
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<p>Flowchart for search results.</p>
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16 pages, 2500 KiB  
Article
Curved Text Line Rectification via Bresenham’s Algorithm and Generalized Additive Models
by Thomas Stogiannopoulos and Ilias Theodorakopoulos
Signals 2024, 5(4), 705-720; https://doi.org/10.3390/signals5040039 - 24 Oct 2024
Viewed by 880
Abstract
This paper presents a methodology for rectifying curved text lines, a crucial process in optical character recognition (OCR) and computer vision. Utilizing generalized additive models (GAMs), the proposed method accurately estimates text curvature and rectifies it into a straight format for improved text [...] Read more.
This paper presents a methodology for rectifying curved text lines, a crucial process in optical character recognition (OCR) and computer vision. Utilizing generalized additive models (GAMs), the proposed method accurately estimates text curvature and rectifies it into a straight format for improved text recognition. The process includes image binarization techniques like Otsu’s thresholding, morphological operations, curve estimation, and the Bresenham line drawing algorithm. The results show significant improvements in OCR accuracy among different challenging distortion scenarios. The implementation, written in Python, demonstrates the potential for enhancing text alignment and rectification in scanned text line images utilizing a flexible, robust, and customizable framework. Full article
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<p>An example demonstrating the outcome of Bresenham’s line algorithm [<a href="#B18-signals-05-00039" class="html-bibr">18</a>]. The grid’s origin <math display="inline"><semantics> <mrow> <mo>(</mo> <mn>0</mn> <mo>,</mo> <mn>0</mn> <mo>)</mo> </mrow> </semantics></math> is positioned in the upper-left corner, with point <math display="inline"><semantics> <mrow> <mo>(</mo> <mn>1</mn> <mo>,</mo> <mn>1</mn> <mo>)</mo> </mrow> </semantics></math> marking the line’s starting point at the top left, and point <math display="inline"><semantics> <mrow> <mo>(</mo> <mn>11</mn> <mo>,</mo> <mn>5</mn> <mo>)</mo> </mrow> </semantics></math> indicating the line’s endpoint at the lower right.</p>
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<p>Example text “Lorem ipsum dolor sit amet” is warped following the <math display="inline"><semantics> <mrow> <mi>y</mi> <mo>=</mo> <msup> <mi>x</mi> <mn>2</mn> </msup> </mrow> </semantics></math> polynomial function.</p>
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<p>The padded image, with a red outline indicating the estimated curve, along with a subtle zebra pattern to emphasize the dimensions of the newly padded area.</p>
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<p>Display of all the line segments across the estimated curve, delineating the region of interest.</p>
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<p>The sample points on the curve are represented by red dots, while the control points are indicated by green dots. The lines connecting these control points are shown in blue.</p>
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<p>The semi-processed image, prior to the final alignment step.</p>
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<p>The final image, fully processed and nearly perfectly aligned, ensuring it is easily readable by both humans and computers.</p>
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<p>A schematic diagram illustrating the data processing workflow in the proposed method.</p>
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<p>(<b>Top</b>): Image displaying slanted text prior to rectification. (<b>Bottom</b>): The same text after undergoing simple vertical adjustments.</p>
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<p>(<b>Top</b>): Image displaying arched text prior to rectification. (<b>Bottom</b>): The same text after undergoing simple vertical adjustments.</p>
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24 pages, 14371 KiB  
Article
An Enhanced Transportation System for People of Determination
by Uma Perumal, Fathe Jeribi and Mohammed Hameed Alhameed
Sensors 2024, 24(19), 6411; https://doi.org/10.3390/s24196411 - 3 Oct 2024
Viewed by 870
Abstract
Visually Impaired Persons (VIPs) have difficulty in recognizing vehicles used for navigation. Additionally, they may not be able to identify the bus to their desired destination. However, the bus bay in which the designated bus stops has not been analyzed in the existing [...] Read more.
Visually Impaired Persons (VIPs) have difficulty in recognizing vehicles used for navigation. Additionally, they may not be able to identify the bus to their desired destination. However, the bus bay in which the designated bus stops has not been analyzed in the existing literature. Thus, a guidance system for VIPs that identifies the correct bus for transportation is presented in this paper. Initially, speech data indicating the VIP’s destination are pre-processed and converted to text. Next, utilizing the Arctan Gradient-activated Recurrent Neural Network (ArcGRNN) model, the number of bays at the location is detected with the help of a Global Positioning System (GPS), input text, and bay location details. Then, the optimal bay is chosen from the detected bays by utilizing the Experienced Perturbed Bacteria Foraging Triangular Optimization Algorithm (EPBFTOA), and an image of the selected bay is captured and pre-processed. Next, the bus is identified utilizing a You Only Look Once (YOLO) series model. Utilizing the Sub-pixel Shuffling Convoluted Encoder–ArcGRNN Decoder (SSCEAD) framework, the text is detected and segmented for the buses identified in the image. From the segmented output, the text is extracted, based on the destination and route of the bus. Finally, regarding the similarity value with respect to the VIP’s destination, a decision is made utilizing the Multi-characteristic Non-linear S-Curve-Fuzzy Rule (MNC-FR). This decision informs the bus conductor about the VIP, such that the bus can be stopped appropriately to pick them up. During testing, the proposed system selected the optimal bay in 247,891 ms, which led to deciding the bus stop for the VIP with a fuzzification time of 34,197 ms. Thus, the proposed model exhibits superior performance over those utilized in prevailing works. Full article
(This article belongs to the Section Intelligent Sensors)
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<p>Framework of the proposed model.</p>
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<p>Architecture of ArcGRNN.</p>
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<p>Graphical representation of the proposed decision generation approach.</p>
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<p>Comparison of the proposed bus bay detection method with existing methods.</p>
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<p>Graphical analysis of FPR and FNR for bus bay detection.</p>
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<p>Training time evaluation.</p>
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<p>Graphical depiction of similarity scores obtained by text detection approaches.</p>
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<p>Performance evaluation of the proposed SSCEAD.</p>
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40 pages, 4095 KiB  
Article
An End-to-End Scene Text Recognition for Bilingual Text
by Bayan M. Albalawi, Amani T. Jamal, Lama A. Al Khuzayem and Olaa A. Alsaedi
Big Data Cogn. Comput. 2024, 8(9), 117; https://doi.org/10.3390/bdcc8090117 - 9 Sep 2024
Viewed by 1216
Abstract
Text localization and recognition from natural scene images has gained a lot of attention recently due to its crucial role in various applications, such as autonomous driving and intelligent navigation. However, two significant gaps exist in this area: (1) prior research has primarily [...] Read more.
Text localization and recognition from natural scene images has gained a lot of attention recently due to its crucial role in various applications, such as autonomous driving and intelligent navigation. However, two significant gaps exist in this area: (1) prior research has primarily focused on recognizing English text, whereas Arabic text has been underrepresented, and (2) most prior research has adopted separate approaches for scene text localization and recognition, as opposed to one integrated framework. To address these gaps, we propose a novel bilingual end-to-end approach that localizes and recognizes both Arabic and English text within a single natural scene image. Specifically, our approach utilizes pre-trained CNN models (ResNet and EfficientNetV2) with kernel representation for localization text and RNN models (LSTM and BiLSTM) with an attention mechanism for text recognition. In addition, the AraElectra Arabic language model was incorporated to enhance Arabic text recognition. Experimental results on the EvArest, ICDAR2017, and ICDAR2019 datasets demonstrated that our model not only achieves superior performance in recognizing horizontally oriented text but also in recognizing multi-oriented and curved Arabic and English text in natural scene images. Full article
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<p>Phases of localization text in natural scene images, image from the EvArEST dataset [<a href="#B10-BDCC-08-00117" class="html-bibr">10</a>]. Green box demonstrated the result of localization phase.</p>
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<p>Phases of recognition text from natural scene images, image from the EvArEST dataset [<a href="#B10-BDCC-08-00117" class="html-bibr">10</a>]. The word in image means “Elegant” in English terms.</p>
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<p>Overview of the scene text recognition system (STR).</p>
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<p>End-to-end scene text recognition phases, image from the EvArEST dataset [<a href="#B10-BDCC-08-00117" class="html-bibr">10</a>]. The white box is the result of localization phase. Text in white illustrates the result of the recognition phase.</p>
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<p>Phases of the proposed end-to-end scene text recognition system, image from ICDAR2017 [<a href="#B39-BDCC-08-00117" class="html-bibr">39</a>]. The green box illustrated the result of localization phase. Text in blue illustrates the result of the recognition phase.</p>
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<p>Structure of MBConv. “+” means element-wise addition. “Conv” and “SE” represent regular convolution and Squeeze and Excitation optimization, respectively.</p>
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<p>Structure of Fused-MBConv. “+” means element-wise addition. “Conv” and “SE” represent regular convolution and Squeeze and Excitation optimization, respectively.</p>
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<p>Structure of the detection head. “Conv” and “BN” represent regular convolution and Batch Normalization, respectively. The words in images mean “Special Offers” in English terms.</p>
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<p>The utilization of the AraELECTRA model in the recognition phase, image from ICDAR2017 [<a href="#B39-BDCC-08-00117" class="html-bibr">39</a>]. The green box refers to the result of the localization phase. Text in blue illustrates the result of the recognition phase.</p>
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<p>An example of an image and its ground-truth format from the ICDAR2019 dataset [<a href="#B41-BDCC-08-00117" class="html-bibr">41</a>].</p>
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<p>Qualitative text localization results of the model from: (<b>a</b>) ICDAR2017 [<a href="#B39-BDCC-08-00117" class="html-bibr">39</a>]; (<b>b</b>) ICDAR2019 [<a href="#B41-BDCC-08-00117" class="html-bibr">41</a>]; and (<b>c</b>) EvArest [<a href="#B10-BDCC-08-00117" class="html-bibr">10</a>]. Green boxes refer to results of localization phase.</p>
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<p>Qualitative end-to-end scene text recognition results of the model from: (<b>a</b>) ICDAR2017 [<a href="#B39-BDCC-08-00117" class="html-bibr">39</a>]; (<b>b</b>) ICDAR2019 [<a href="#B41-BDCC-08-00117" class="html-bibr">41</a>]; and (<b>c</b>) EvArest [<a href="#B10-BDCC-08-00117" class="html-bibr">10</a>]. Green boxes refer to results of localization phase. Text in blue illustrates the result of the recognition phase.</p>
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<p>The F-Score results of the EvArEST dataset using ResNet-18 and EfficientNetV2-S.</p>
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<p>The F-Score results of the EvArEST dataset using ResNet-50 and EfficientNetV2-M.</p>
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<p>The LSTM model’s F-Score outcomes for word direction prediction in (A) various directions and (B) unified direction.</p>
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<p>The BiLSTM model’s F-Score outcomes for word direction prediction in (A) various directions and (B) unified direction.</p>
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<p>Failure case in localizing vertical Arabic text, image from the ICDAR2019 dataset [<a href="#B41-BDCC-08-00117" class="html-bibr">41</a>]. Green box refers to the results of the localization phase.</p>
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<p>Failure case in recognizing Arabic text, image from EvArest [<a href="#B10-BDCC-08-00117" class="html-bibr">10</a>]. Green box refers to the results of the localization phase. Words in image in English terms: Amal, shaving, and beautification.</p>
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15 pages, 5521 KiB  
Article
A Historical Handwritten French Manuscripts Text Detection Method in Full Pages
by Rui Sang, Shili Zhao, Yan Meng, Mingxian Zhang, Xuefei Li, Huijie Xia and Ran Zhao
Information 2024, 15(8), 483; https://doi.org/10.3390/info15080483 - 14 Aug 2024
Viewed by 915
Abstract
Historical handwritten manuscripts pose challenges to automated recognition techniques due to their unique handwriting styles and cultural backgrounds. In order to solve the problems of complex text word misdetection, omission, and insufficient detection of wide-pitch curved text, this study proposes a high-precision text [...] Read more.
Historical handwritten manuscripts pose challenges to automated recognition techniques due to their unique handwriting styles and cultural backgrounds. In order to solve the problems of complex text word misdetection, omission, and insufficient detection of wide-pitch curved text, this study proposes a high-precision text detection method based on improved YOLOv8s. Firstly, the Swin Transformer is used to replace C2f at the end of the backbone network to solve the shortcomings of fine-grained information loss and insufficient learning features in text word detection. Secondly, the Dysample (Dynamic Upsampling Operator) method is used to retain more detailed features of the target and overcome the shortcomings of information loss in traditional upsampling to realize the text detection task for dense targets. Then, the LSK (Large Selective Kernel) module is added to the detection head to dynamically adjust the feature extraction receptive field, which solves the cases of extreme aspect ratio words, unfocused small text, and complex shape text in text detection. Finally, in order to overcome the CIOU (Complete Intersection Over Union) loss in target box regression with unclear aspect ratio, insensitive to size change, and insufficient correlation between target coordinates, Gaussian Wasserstein Distance (GWD) is introduced to modify the regression loss to measure the similarity between the two bounding boxes in order to obtain high-quality bounding boxes. Compared with the State-of-the-Art methods, the proposed method achieves optimal performance in text detection, with the precision and [email protected] reaching 86.3% and 82.4%, which are 8.1% and 6.7% higher than the original method, respectively. The advancement of each module is verified by ablation experiments. The experimental results show that the method proposed in this study can effectively realize complex text detection and provide a powerful technical means for historical manuscript reproduction. Full article
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<p>An example of a historical French handwritten manuscript (Source: gallica.bnf.fr/Bibliothèque nationale de France. Département des manuscrits. Français 17238, <a href="https://gallica.bnf.fr/ark:/12148/btv1b90616522/f5.item.r=Traductions%20et%20extraits%20de%20livres%20chinois" target="_blank">https://gallica.bnf.fr/ark:/12148/btv1b90616522/f5.item.r=Traductions%20et%20extraits%20de%20livres%20chinois</a>) (accessed on 18 July 2024).</p>
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<p>Comparison of super-resolution effects of different models on blurred French text (Source: gallica.bnf.fr/Bibliothèque nationale de France. Département des manuscrits. Français 17239, <a href="https://gallica.bnf.fr/ark:/12148/btv1b90615371/f49.item.r=francais%2017239" target="_blank">https://gallica.bnf.fr/ark:/12148/btv1b90615371/f49.item.r=francais%2017239</a>) (accessed on 18 July 2024).</p>
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<p>Improved YOLOv8s network architecture (the red box shows the improved module).</p>
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<p>Swin Transformer network module structure schematic diagram.</p>
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<p>Dysample module structure schematic diagram.</p>
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<p>LSK module structure schematic diagram.</p>
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<p>Visualized detection results of different text detection models (Source: gallica.bnf.fr/Bibliothèque nationale de France. Département des manuscrits. Français 17239, <a href="https://gallica.bnf.fr/ark:/12148/btv1b90615371/f16.item.r=francais%2017239" target="_blank">https://gallica.bnf.fr/ark:/12148/btv1b90615371/f16.item.r=francais%2017239</a>) (accessed on 18 July 2024).</p>
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<p>Detection results of original and enhanced image visualization (Source: gallica.bnf.fr/Bibliothèque nationale de France. Département des manuscrits. Français 17239, <a href="https://gallica.bnf.fr/ark:/12148/btv1b90615371/f16.item.r=francais%2017239" target="_blank">https://gallica.bnf.fr/ark:/12148/btv1b90615371/f16.item.r=francais%2017239</a>) (accessed on 18 July 2024).</p>
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22 pages, 13011 KiB  
Article
RA-YOLOv8: An Improved YOLOv8 Seal Text Detection Method
by Han Sun, Chaohong Tan, Si Pang, Hancheng Wang and Baohua Huang
Electronics 2024, 13(15), 3001; https://doi.org/10.3390/electronics13153001 - 30 Jul 2024
Viewed by 1620
Abstract
To detect text from electronic seals that have significant background interference, blurring, text overlapping, and curving, an improved YOLOv8 model named RA-YOLOv8 was developed. The model is primarily based on YOLOv8, with optimized structures in its backbone and neck. The receptive-field attention and [...] Read more.
To detect text from electronic seals that have significant background interference, blurring, text overlapping, and curving, an improved YOLOv8 model named RA-YOLOv8 was developed. The model is primarily based on YOLOv8, with optimized structures in its backbone and neck. The receptive-field attention and efficient multi-scale attention (RFEMA) module is introduced in the backbone. The model’s ability to extract and integrate local and global features is enhanced by combining the attention on the receptive-field spatial feature of the receptive-field attention and coordinate attention (RFCA) module and the cross-spatial learning of the efficient multi-scale attention (EMA) module. The Alterable Kernel Convolution (AKConv) module is incorporated in the neck, enhancing the model’s detection accuracy of curved text by dynamically adjusting the sampling position. Furthermore, to boost the model’s detection performance, the original loss function is replaced with the bounding box regression loss function of Minimum Point Distance Intersection over Union (MPDIoU). Experimental results demonstrate that RA-YOLOv8 surpasses YOLOv8 in terms of precision, recall, and F1 value, with improvements of 0.4%, 1.6%, and 1.03%, respectively, validating its effectiveness and utility in seal text detection. Full article
(This article belongs to the Special Issue Advances of Artificial Intelligence and Vision Applications)
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<p>Structure of YOLOv8.</p>
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<p>Improved structure of YOLOv8.</p>
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<p>Structure of RFEMA module.</p>
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<p>Structure of RFCA module.</p>
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<p>Structure of EMA module.</p>
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<p>Structure of AKConv module. The red frame in the figure represents the sample shape.</p>
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<p>(<b>a</b>) The predicted bounding box is outside the ground truth bounding box, at this time L<sub>CIoU</sub> = 0.75, L<sub>GIoU</sub> = 0.75, L<sub>MPDIoU</sub> = 0.79; (<b>b</b>) The predicted bounding box is inside the ground truth bounding box, at this time L<sub>CIoU</sub> = 0.75, L<sub>GIoU</sub> = 0.75, L<sub>MPDIoU</sub> = 0.76.</p>
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<p>Different types of seals in the data set.</p>
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<p>Dataset label distribution map.</p>
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<p>Comparative experiments of yolo series.</p>
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<p>Performance comparison experiment of yolo series models.</p>
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<p>Visualization results of different models.</p>
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<p>Visualized results of failed cases.</p>
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<p>Visualization results of different modules.</p>
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<p>Performance comparison experiment of different modules.</p>
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12 pages, 868 KiB  
Article
Trademark Text Recognition Combining SwinTransformer and Feature-Query Mechanisms
by Boxiu Zhou, Xiuhui Wang, Wenchao Zhou and Longwen Li
Electronics 2024, 13(14), 2814; https://doi.org/10.3390/electronics13142814 - 17 Jul 2024
Viewed by 729
Abstract
The task of trademark text recognition is a fundamental component of scene text recognition (STR), which currently faces a number of challenges, including the presence of unordered, irregular or curved text, as well as text that is distorted or rotated. In applications such [...] Read more.
The task of trademark text recognition is a fundamental component of scene text recognition (STR), which currently faces a number of challenges, including the presence of unordered, irregular or curved text, as well as text that is distorted or rotated. In applications such as trademark infringement detection and analysis of brand effects, the diversification of artistic fonts in trademarks and the complexity of the product surfaces where the trademarks are located pose major challenges for relevant research. To tackle these issues, this paper proposes a novel recognition framework named SwinCornerTR, which aims to enhance the accuracy and robustness of trademark text recognition. Firstly, a novel feature-extraction network based on SwinTransformer with EFPN (enhanced feature pyramid network) is proposed. By incorporating SwinTransformer as the backbone, efficient capture of global information in trademark images is achieved through the self-attention mechanism and enhanced feature pyramid module, providing more accurate and expressive feature representations for subsequent text extraction. Then, during the encoding stage, a novel feature point-retrieval algorithm based on corner detection is designed. The OTSU-based fast corner detector is presented to generate a corner map, achieving efficient and accurate corner detection. Furthermore, in the encoding phase, a feature point-retrieval mechanism based on corner detection is introduced to achieve priority selection of key-point regions, eliminating character-to-character lines and suppressing background interference. Finally, we conducted extensive experiments on two open-access benchmark datasets, SVT and CUTE80, as well as a self-constructed trademark dataset, to assess the effectiveness of the proposed method. Our results showed that the proposed method achieved accuracies of 92.9%, 92.3% and 84.8%, respectively, on these datasets. These results demonstrate the effectiveness and robustness of the proposed method in the analysis of trademark data. Full article
(This article belongs to the Section Artificial Intelligence)
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<p>Architecture of the proposed SwinCornerTR network.</p>
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<p>Architecture of the proposed SwinTransformer.</p>
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<p>The SwinTransformer Block.</p>
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<p>A demonstration of SwinTransformer’s window partitioning.</p>
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<p>Architecture of the proposed EFPN.</p>
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<p>Comparison of corner map.</p>
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<p>Examples of trademark text-recognition result, where different scenarios denoted by ’a’ to ’f’ represent distinct typical situations.</p>
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14 pages, 4537 KiB  
Article
Multimodal Hateful Meme Classification Based on Transfer Learning and a Cross-Mask Mechanism
by Fan Wu, Guolian Chen, Junkuo Cao, Yuhan Yan and Zhongneng Li
Electronics 2024, 13(14), 2780; https://doi.org/10.3390/electronics13142780 - 15 Jul 2024
Viewed by 1518
Abstract
Hateful memes are malicious and biased sentiment information widely spread on the internet. Detecting hateful memes differs from traditional multimodal tasks because, in conventional tasks, visual and textual information align semantically. However, the challenge in detecting hateful memes lies in their unique multimodal [...] Read more.
Hateful memes are malicious and biased sentiment information widely spread on the internet. Detecting hateful memes differs from traditional multimodal tasks because, in conventional tasks, visual and textual information align semantically. However, the challenge in detecting hateful memes lies in their unique multimodal nature, where images and text in memes may be weak or unrelated, requiring models to understand the content and perform multimodal reasoning. To address this issue, we introduce a multimodal fine-grained hateful memes detection model named “TCAM”. The model leverages advanced encoding techniques from TweetEval and CLIP and introduces enhanced Cross-Attention and Cross-Mask Mechanisms (CAM) in the feature fusion stage to improve multimodal correlations. It effectively embeds fine-grained features of data and image descriptions into the model through transfer learning. This paper uses the Area Under the Receiver Operating Characteristic Curve (AUROC) as the primary metric to evaluate the model’s discriminatory ability. This approach achieved an AUROC score of 0.8362 and an accuracy score of 0.764 on the Facebook Hateful Memes Challenge (FHMC) dataset, confirming its high discriminatory capability. The TCAM model demonstrates relatively superior performance compared to ensemble machine learning methods. Full article
(This article belongs to the Special Issue Application of Data Mining in Social Media)
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<p>A graphical representation of multimodal hateful memes in the FHMC competition. The (<b>left image</b>) signifies expressions of hatred, while the (<b>right image</b>) represents non-hateful expressions (Caution: This content may involve sensitive topics; please read objectively and rationally. This study aims to delve into the essence and impact of hateful memes, which are not intended for misleading or misinterpretation and do not constitute any specific recommendations or mandatory opinions).</p>
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<p>The AUROC of fine-grained features in the “hate” subset of the FHMC dataset.</p>
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<p>Word clouds of the original text and image descriptions from the FHMC dataset ((<b>left image</b>) for the original text; (<b>right image</b>) for image descriptions).</p>
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<p>Word clouds of the original text and image descriptions from the FHMC dataset ((<b>left image</b>) for the original text; (<b>right image</b>) for image descriptions).</p>
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<p>The loss curves and AUC curves on the FHMC test set. (<b>a</b>) The loss curves on the FHMC test set. (<b>b</b>) The AUC curves on the FHMC test set.</p>
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<p>The confusion matrices on the FHMC test set. (<b>a</b>) The TCAM model. (<b>b</b>) The TCAM_no_pd model. (<b>c</b>) The TCAM_no_cg model. (<b>d</b>) The TCAM_no_cam model.</p>
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20 pages, 2173 KiB  
Article
Quantitative Evaluation of China’s Biogenetic Resources Conservation Policies Based on the Policy Modeling Consistency Index Model
by Liwen Qi, Wenjing Chen, Chunyan Li, Xiaoting Song and Lanqing Ge
Sustainability 2024, 16(12), 5158; https://doi.org/10.3390/su16125158 - 17 Jun 2024
Viewed by 1094
Abstract
Biogenetic resources are the foundation of biodiversity and are of great significance to the sustainability of human society. The effective promotion of biogenetic resource conservation depends on the scientific formulation and implementation of relevant policies, so the quantitative evaluation of biogenetic resource conservation [...] Read more.
Biogenetic resources are the foundation of biodiversity and are of great significance to the sustainability of human society. The effective promotion of biogenetic resource conservation depends on the scientific formulation and implementation of relevant policies, so the quantitative evaluation of biogenetic resource conservation policies can provide decision support for the next step of policy formulation. Based on text analysis, social network analysis, and the construction of the PMC index model, this study selected 132 policy samples issued by the Chinese government in the field of biogenetic resources, established an evaluation system for China’s biogenetic resources policies, which contains 10 first-level indicators and 55 s-level indicators, and drew the PMC curve diagram accordingly to quantitatively evaluate China’s biogenetic resources policies. The results show that China’s biogenetic resources policies are generally at a good level, which can meet the current practical needs of biogenetic resources conservation, but there are problems such as the lack of policy forecasts in the relevant policy texts, the lack of flexible planning in the short and medium term, the lack of co-operation among the policy issuers, and the insufficient guidance of innovation. Based on the results, this article puts forward suggestions for improving China’s biogenetic resource conservation policies. Full article
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<p>Tree diagram of keyword clustering for biological genetic resource policies.</p>
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<p>PMC surface diagram for P1.</p>
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<p>PMC surface diagram for P2.</p>
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<p>PMC surface diagram for P3.</p>
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<p>PMC surface diagram for P4.</p>
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<p>PMC surface diagram for P5.</p>
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<p>PMC surface diagram for P6.</p>
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<p>PMC surface diagram for P7.</p>
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<p>PMC surface diagram for P8.</p>
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<p>PMC surface diagram for P9.</p>
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<p>PMC surface diagram for P10.</p>
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26 pages, 3411 KiB  
Article
Predicting the Direction of NEPSE Index Movement with News Headlines Using Machine Learning
by Keshab Raj Dahal, Ankrit Gupta and Nawa Raj Pokhrel
Econometrics 2024, 12(2), 16; https://doi.org/10.3390/econometrics12020016 - 11 Jun 2024
Viewed by 3049
Abstract
Predicting stock market movement direction is a challenging task due to its fuzzy, chaotic, volatile, nonlinear, and complex nature. However, with advancements in artificial intelligence, abundant data availability, and improved computational capabilities, creating robust models capable of accurately predicting stock market movement is [...] Read more.
Predicting stock market movement direction is a challenging task due to its fuzzy, chaotic, volatile, nonlinear, and complex nature. However, with advancements in artificial intelligence, abundant data availability, and improved computational capabilities, creating robust models capable of accurately predicting stock market movement is now feasible. This study aims to construct a predictive model using news headlines to predict stock market movement direction. It conducts a comparative analysis of five supervised classification machine learning algorithms—logistic regression (LR), support vector machine (SVM), random forest (RF), extreme gradient boosting (XGBoost), and artificial neural network (ANN)—to predict the next day’s movement direction of the close price of the Nepal Stock Exchange (NEPSE) index. Sentiment scores from news headlines are computed using the Valence Aware Dictionary for Sentiment Reasoning (VADER) and TextBlob sentiment analyzer. The models’ performance is evaluated based on sensitivity, specificity, accuracy, and the area under the receiver operating characteristic (ROC) curve (AUC). Experimental results reveal that all five models perform equally well when using sentiment scores from the TextBlob analyzer. Similarly, all models exhibit almost identical performance when using sentiment scores from the VADER analyzer, except for minor variations in AUC in SVM vs. LR and SVM vs. ANN. Moreover, models perform relatively better when using sentiment scores from the TextBlob analyzer compared to the VADER analyzer. These findings are further validated through statistical tests. Full article
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<p>Schematic diagram of the proposed research framework.</p>
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<p>General architecture of neural network with <span class="html-italic">n</span> predictors, a single hidden layer with <span class="html-italic">m</span> neurons, and an output layer.</p>
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<p>Experimental design.</p>
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<p>NEPSE closing price between 1 January 2019 to 31 December 2023.</p>
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<p>Concatenation of movement direction and news sentiment score.</p>
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<p>Plot of loss function vs. the number of epochs on the TextBlob sentiment data on the left and VADER sentiment data on the right.</p>
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<p>Multiple bar plots of the metrics on the test dataset using ML models: TextBlob sentiment data on the left and VADER sentiment data on the right.</p>
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<p><b>Left</b>: ROC curves of the five models for TextBlob data. <b>Right</b>: ROC curves of the five models for VADER sentiment data.</p>
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17 pages, 5144 KiB  
Article
Deep Learning-Based Truthful and Deceptive Hotel Reviews
by Devbrat Gupta, Anuja Bhargava, Diwakar Agarwal, Mohammed H. Alsharif, Peerapong Uthansakul, Monthippa Uthansakul and Ayman A. Aly
Sustainability 2024, 16(11), 4514; https://doi.org/10.3390/su16114514 - 26 May 2024
Cited by 1 | Viewed by 1517
Abstract
For sustainable hospitality and tourism, the validity of online evaluations is crucial at a time when they influence travelers’ choices. Understanding the facts and conducting a thorough investigation to distinguish between truthful and deceptive hotel reviews are crucial. The urgent need to discern [...] Read more.
For sustainable hospitality and tourism, the validity of online evaluations is crucial at a time when they influence travelers’ choices. Understanding the facts and conducting a thorough investigation to distinguish between truthful and deceptive hotel reviews are crucial. The urgent need to discern between truthful and deceptive hotel reviews is addressed by the current study. This misleading “opinion spam” is common in the hospitality sector, misleading potential customers and harming the standing of hotel review websites. This data science project aims to create a reliable detection system that correctly recognizes and classifies hotel reviews as either true or misleading. When it comes to natural language processing, sentiment analysis is essential for determining the text’s emotional tone. With an 800-instance dataset comprising true and false reviews, this study investigates the sentiment analysis performance of three deep learning models: Convolutional Neural Network (CNN), Long Short-Term Memory (LSTM), and Recurrent Neural Network (RNN). Among the training, testing, and validation sets, the CNN model yielded the highest accuracy rates, measuring 98%, 77%, and 80%, respectively. Despite showing balanced precision and recall, the LSTM model was not as accurate as the CNN model, with an accuracy of 60%. There were difficulties in capturing sequential relationships, for which the RNN model further trailed, with accuracy rates of 57%, 57%, and 58%. A thorough assessment of every model’s performance was conducted using ROC curves and classification reports. Full article
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<p>Block diagram of workflow of identification of opinion spam in hotel reviews.</p>
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<p>Bar plot of the distribution of classes (truthful vs. deceptive).</p>
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<p>Bar plot of the top 20 words by frequency.</p>
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<p>Histogram distribution of word lengths in the reviews, split by truthfulness and deceptiveness.</p>
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<p>Histogram distribution of character lengths in the reviews, split by truthfulness and deceptiveness.</p>
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<p>A visual representation of the most frequent words as a word cloud map for truthful and deceptive reviews.</p>
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<p>Bar plot of TF-IDF scores for truthful and deceptive reviews.</p>
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<p>Scatter plot of a two-dimensional representation, in terms of data points, of the word embeddings for truthful and deceptive reviews.</p>
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<p>Distribution of informative and imaginative words with truthful and deceptive labels.</p>
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<p>Sentiment distribution polarity.</p>
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<p>Top words by frequency distribution.</p>
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<p>Plot of training and validation accuracy history comparison.</p>
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<p>ROC curve.</p>
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21 pages, 2358 KiB  
Review
Useful Quantities and Diagram Types for Diagnosis and Monitoring of Electrochemical Energy Converters Using Impedance Spectroscopy: State of the Art, Review and Outlook
by Peter Kurzweil, Wolfgang Scheuerpflug, Christian Schell and Josef Schottenbauer
Batteries 2024, 10(6), 177; https://doi.org/10.3390/batteries10060177 - 24 May 2024
Cited by 1 | Viewed by 1304
Abstract
The concept of pseudocapacitance is explored as a rapid and universal method for the state of health (SOH) determination of batteries and supercapacitors. In contrast to this, the state of the art considers the degradation of a series of full charge/discharge cycles. Lithium-ion [...] Read more.
The concept of pseudocapacitance is explored as a rapid and universal method for the state of health (SOH) determination of batteries and supercapacitors. In contrast to this, the state of the art considers the degradation of a series of full charge/discharge cycles. Lithium-ion batteries, sodium-ion batteries and supercapacitors of different cell chemistries are studied by impedance spectroscopy during lifetime testing. Faradaic and capacitive charge storage are distinguished by the relationship between the stored electric charge and capacitance. Batteries with a flat voltage–charge curve are best suited for impedance spectroscopy. There is a slight loss in the linear correlation between the pseudocapacitance and Ah capacity in regions of overcharge and deep discharge. The correct calculation of quantities related to complex impedance and differential capacitance is outlined, which may also be useful as an introductory text and tutorial for newcomers to the field. Novel diagram types are proposed for the purpose of the instant performance and failure diagnosis of batteries and supercapacitors. Full article
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<p>Basic graphical representations of impedance-related quantities for a simple equivalent circuit diagram in the frequency range of 1 mHz to 1 MHz. Mathematical convention. <span class="html-italic">R</span> = resistance, <span class="html-italic">X</span> = reactance, <span class="html-italic">G</span> = conductance, <span class="html-italic">B</span> = susceptance, <span class="html-italic">C</span> = capacitance, <span class="html-italic">D</span> = dissipation, |<span class="html-italic"><span class="underline">Z</span></span>| = impedance modulus, φ = phase shift between voltage and current, τ = time constant. Solid lines (–): measured values for an electric circuit with real resistors and capacitor. Dotted (······): calculated values for the ideal network.</p>
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<p>Stepwise impedance spectrum analysis. (<b>a</b>) The impedance spectrum of a lead dioxide electrode (PbO<sub>2</sub>|Ti) in sulfuric acid at a current density of 8.5 mA cm<sup>−2</sup>. (<b>b</b>) The pseudocapacitance, corrected by the electrolyte resistance and the charge transfer resistance. (<b>c</b>) The equivalent circuit derived from the stepwise analysis according to Equations (11)–(15): e = electrolyte, L = inner layer between titanium support and PbO<sub>2</sub> active layer, D = double layer and charge transfer reaction, 0 = residual faradaic impedance. Correction steps: <b>A</b> electrolyte, <b>B</b> inner layer, <b>C</b> charge-transfer.</p>
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<p>Accelerated aging test of a supercapacitor (Vinatech HyCap Neo, 10 F, 2.7 V, Jeonju, Republic of Korea). (<b>a</b>) Equivalent circuit: <span class="html-italic">R</span><sub>S</sub> = electrolyte, <span class="html-italic">R</span><sub>D</sub> = grain boundaries and charge transfer, <span class="html-italic">C</span><sub>D</sub> = double layer, <span class="html-italic"><span class="underline">Z</span></span><sub>W</sub> = Warburg impedance: loss of active surface area by pore clogging and growing interlayer between carbon and aluminum support, <span class="html-italic"><span class="underline">Z</span></span><sub>N</sub> = Nernst diffusion impedance attributed to mass transfer (adsorption of ions on porous carbon electrodes and ion depletion at electrode/electrolyte interface). (<b>b</b>) Measured impedance in frequency range between 0,1 Hz and 10 kHz in different diagram types. Mathematical convention. <span class="html-italic">R</span> = resistance, <span class="html-italic">X</span> = reactance, <span class="html-italic">G</span> = conductance, <span class="html-italic">B</span> = susceptance, <span class="html-italic">C</span> = capacitance, <span class="html-italic">D</span> = dissipation, |<span class="html-italic"><span class="underline">Z</span></span>| = impedance modulus, <span class="html-italic">φ</span> = phase shift, <span class="html-italic">τ</span> = time constant. The red arrows show the trend of the changes during aging.</p>
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<p>Impedance data of a lithium-ion battery (LithiumWerks 26650 cell, LiFePO<sub>4</sub>, 3.3 V, 2.5 Ah, USA) during lifetime testing. (<b>a</b>) Relative increase in ohmic resistance <span class="html-italic">R</span> (0.1 Hz) and impedance modulus <span class="html-italic">Z</span> (0.1 Hz) at different states of charge (SOC). (<b>b</b>) Relative change of reactance <span class="html-italic">X</span> (0.1 Hz) and phase shift φ (0.1 Hz). (<b>c</b>) Linear increase in pseudocapacitance <span class="html-italic">C</span> (0.1 Hz) when corrected by the electrolyte resistance. (<b>d</b>) Correlation of available electric charge (battery capacity) with cell resistance <span class="html-italic">R</span> (0.1 Hz) and (<b>e</b>) pseudocapacitance <span class="html-italic">C</span> (0.1 Hz), corrected by the electrolyte resistance.</p>
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<p>Lifetime test of a lithium-ion battery (LithiumWerks 26650 cell, LiFePO<sub>4</sub>, 3.3 V, 2.5 Ah). (<b>a</b>) Measured impedance of the battery at pre-defined frequencies in dependence on the state of charge (SOC). (<b>b</b>) Measured impedance at the end of life. <span class="html-italic">C</span> = pseudocapacitance (corrected by the electrolyte resistance according to Equation (6)), <span class="html-italic">D</span> = dissipation (corrected by the electrolyte resistance), <span class="html-italic">R</span> = cell resistance (real part of the impedance).</p>
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<p>Characterization of a sodium-ion battery (Shenzhen Mushang Electronics, NA18650-1250, 3.0 V, 1.25 Ah, China). (<b>a</b>) Impedance spectra in the complex plane at different states of charge. (<b>b</b>) Pseudocapacitance and cell resistance at different SOCs. Electrolyte resistance corrected. (<b>c</b>) Pseudocapacitance <span class="html-italic">C</span>, dissipation <span class="html-italic">D</span>, and cell voltage <span class="html-italic">U</span> as SOC indicators. (<b>d</b>) Cell voltage versus capacity at different discharge currents at room temperature. (<b>e</b>) Temperature dependence of electric charge with reference to the rated capacity. (<b>f</b>) Example: differential capacity (‘ICA’) and differential voltage (‘DVA’) along the constant current discharge curve (<span class="html-italic">U</span> cell voltage). (<b>g</b>) Cycle life test: <span class="html-italic">C</span> = pseudocapacitance (electrolyte resistance corrected), <span class="html-italic">R</span> = cell resistance.</p>
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<p>Changes in the impedance spectra during the aging of an LCO battery (Panasonic UR18650 FK, Japan) at full charge (SOC = 1). There is an apparent improvement in internal resistance during the first hundred cycles before the battery undergoes normal aging over a thousand charge/discharge cycles.</p>
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