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Journal of Trace Elements and Minerals 2025年 12卷

作者： Anjum, Mavia Siddique, Naila Younis, Hannan Shafique, Munib Ahmed Munawar, Sadia Zubair, Mohsina Younas, Huzaifa Abbas, Ansar Faiz, Yasir Chemistry Division Directorate of Science Pakistan Institute of Nuclear Science & Technology (PINSTECH) Islamabad 45650 Pakistan Department of Physics University of Idaho 691 Ash St Moscow 83844 ID United States Research & Investigation Section Pakistan Environmental Protection Agency (Pak-EPA) Ministry of Climate Change & Environmental Coordination Islamabad Pakistan Radiation Physics Lab COMSATS University Islamabad Pakistan College of Engineering & Computer Science California State University Northridge 18111 Nordhoff St Northridge 91330 CA United States

Introduction: Global warming is intensified by atmospheric pollution, with industrial activities significantly contributing to this issue. This study investigates air pollution levels in the industrial area of Islamabad, the capital of Pakistan, a developing South Asian nation grappling with severe air quality threats. Study area: This study was designed to assess the pollution levels in the air of industrial area of Islamabad, Pakistan Methodology: Fine (size < 2.5µm: PM_2.5) and coarse (size between 2.5 and 10 µm: PM_2.5–10) particulate matter samples were collected on Polycarbonate air filters for three seasons in 2023. The elemental composition of PM was quantified using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Results: The average PM_2.5 (40.42 µg m⁻³) and PM_2.5–10 (221 µg m⁻³) concentrations exceeded Pakistan Environmental Protection Agency (Pak-EPA) limits (PM_2.5: 35 µg m⁻³;PM_2.5–10: 150 µg m⁻³, respectively). In PM_2.5, Na showed the highest mean concentration (8670 ng m⁻³), As the lowest (40 ng m⁻³);in PM_2.5–10, Ca was highest (5476 ng m⁻³), Zr lowest (28 ng m⁻³). Seasonal variations revealed for PM_2.5–10 Ca peaked at 7800 ng m⁻³ in autumn, with Mg, Si, Fe, and Al fluctuating significantly, while toxic elements As, Pb, Co and Cr decreased from spring to autumn. In PM_2.5, Ca peaked at 7043 ng m⁻³ and Na remained elevated in spring, with crustal and toxic metals concentration decreasing from spring to autumn. Depositional flux was high for Ca and Ba in PM_2.5–10, and Na, Cr, and Cu in PM_2.5. The Enrichment factor and pollution index indicated higher contamination by Cr, Cu, Pb, S, Zn, Ni, As, Li, Mo, Sn, and Ag. Environmental Protection Agency Positive Matrix Factorization (EPA-PMF) identified steel

关键词： Air quality assessment Elemental analysis Heavy metal pollution HYSPLIT Positive matrix factorization

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A decision modeling approach for smart e-tourism data management applications based on spherical fuzzy rough environment

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Applied Soft Computing 2023年 143卷

作者： Mohammed, R.T. Alamoodi, A.H. Albahri, O.S. Zaidan, A.A. AlSattar, H.A. Aickelin, Uwe Albahri, A.S. Zaidan, B.B. Ismail, Amelia Ritahani Malik, R.Q. Universiti Pendidikan Sultan Idris Tanjung Malim35900 Malaysia Sulaymaniyah Iraq Department of Computer Science and Information Technology La Trobe University Melbourne VIC Australia SP Jain School of Global Management Sydney Australia Department of Business Administration College of Administrative Science The University of Mashreq Baghdad10021 Iraq School of Computing and Information Systems University of Melbourne 700 Swanston Street Victoria3010 Australia Baghdad Iraq Future Technology Research Center National Yunlin University of Science and Technology 123 University Road Section 3 Douliou Yunlin64002 Taiwan International Islamic University Malaysia Kuala Lumpur Malaysia Medical Instrumentation Techniques Engineering Department Al-Mustaqbal University College Babylon Iraq Computer Techniques Engineering Department Mazaya University College Thi-Qar Nassiriya Iraq

The technology deployment in smart e-tourism brings high potential in terms of customer data, events, reservations, and others. It acts as an effective and personalized guide to aid travelers. There is an increasing variety of smart e-tourism apps with multiple categories and criteria, but in terms of decision making, this presents a multicriteria complex problem to determine the best app from a group of available options with high criteria subjectivity. Literature reviews have evaluated and modeled the existing smart e-tourism apps alternatives, but informational uncertainty remains. The fuzzy sets and Multi-Attribute Decision Analysis (MADA) were used to handle the subjectivity issue. However, this process includes levels of uncertainty, which affects the decisions made and still an open issues. Spherical fuzzy rough sets (SFRSs) environment are useful in this situation for resolving fuzziness and ambiguity. This paper proposed a decision modeling approach for smart E-Tourism data management applications based on SFRSs environment. For methodology: firstly, a decision matrix is adopted for 5 different categories of Smart E-tourism's system applications on the basis of the integrated 12 evaluation criteria. Secondly, a new formulation and development formulating a new extension of FWZIC, called a Spherical Fuzzy Rough-Weighted Zero-Inconsistency (SFR-WZIC), for weighting the smart key concept attributes involved in modeling smart e-tourism, whereas a new formulation and development for a new extension of FDOSM, called a Spherical Fuzzy Rough Decision by Opinion Score Method (SFR-DOSM), for modeling the applications of smart e-tourism per each e-tourism category;then, the new developments are integrated. The proposed methods were evaluated using systematic ranking and sensitivity analysis. © 2023 Elsevier B.V.

关键词： Decision making

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Assessment of chronic radiation proctopathy and radiofrequency ablation treatment follow-up with optical coherence tomography angiography: A pilot study

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World Journal of Gastroenterology 2019年第16期25卷 1997-2009页

作者： Osman Oguz Ahsen Kaicheng Liang Hsiang-Chieh Lee Zhao Wang James G Fujimoto Hiroshi Mashimo Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Gastroenterology Section VA Boston Healthcare System Harvard School of Medicine Boston

BACKGROUND Chronic radiation proctopathy(CRP) occurs as a result of pelvic radiation therapy and is associated with formation of abnormal vasculature that may lead to persistent rectal bleeding. While incidence is declining due to refinement of radiation delivery techniques, CRP remains one of the major complications of pelvic radiation therapy and significantly affects patient quality of *** ablation(RFA) is an emerging treatment modality for eradicating abnormal vasculature associated with CRP. However, questions remain regarding CRP pathophysiology and optimal disease *** To study feasibility of optical coherence tomography angiography(OCTA) for investigating subsurface vascular alterations in CRP and response to RFA *** Two patients with normal rectum and 8 patients referred for, or undergoing endoscopic RFA treatment for CRP were imaged with a prototype ultrahighspeed optical coherence tomography(OCT) system over 15 OCT/colonoscopy visits(2 normal patients, 5 RFA-na?ve patients, 8 RFA-follow-up visits). OCT and OCTA was performed by placing the OCT catheter onto the dentate line and rectum without endoscopic guidance. OCTA enabled depth-resolved microvasculature imaging using motion contrast from flowing blood, withoutrequiring injected dyes. OCTA features of normal and abnormal microvasculature were assessed in the mucosa and submucosa. Blinded reading of OCTA images was performed to assess the association of abnormal rectal microvasculature with CRP and RFA treatment, and rectal telangiectasia density endoscopic *** OCTA/OCT images are intrinsically co-registered and enabled depth-resolved visualization of microvasculature in the mucosa and submucosa. OCTA visualized normal vascular patterns with regular honeycomb patterns vs abnormal vasculature with distorted honeycomb patterns and ectatic/tortuous microvasculature in the rectal mucosa. Normal arterioles and venules < 200 μm in diameter versus abnormal he

关键词： Optical coherence tomography Optical coherence tomography angiography Radiofrequency ablation Chronic radiation proctopathy Rectal telangiectasia density scoring system Subsurface microvascular imaging

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Modeling Method for DFIG-Based Wind Farm in High-Efficiency Real-Time Electromagnetic Transient (EMT) Simulations

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IEEE Transactions on Power Electronics 2025年

作者： Liu, Yifan Xu, Jianzhong Zhu, Yiyang Tian, Zhaoxuan Zhao, Chengyong Li, Gen State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources China Energy Technology and Computer Science Section Department of Engineering Technology and Didactics Ballerup2750 Denmark

With the increasing integration of renewable energy into power systems, electromagnetic transient (EMT) simulation has become indispensable for accurate system analysis. However, the complexity of wind turbine (WT) modeling, characterized by a large number of electrical nodes, poses significant challenges and necessitates substantial real-time simulation hardware. Existing methods for reducing circuit complexity improve simulation efficiency but are each associated with inherent limitations. Aggregation methods sacrifice considerable internal station information, while existing decoupling techniques are constrained by specific requirements. This paper proposes a real-time simulation model for a Doubly Fed Induction Generator (DFIG)-based wind farm (WF) using latency decoupling and a multi-level nested fast and simultaneous solution (M-NFSS) approach, effectively reducing node count while preserving internal details. A WF test model is implemented in RTDS for validation. Results demonstrate highly accurate impedance characteristics and time-domain waveforms of the proposed model, utilizing only 33.3% of the hardware resources compared to the traditional detailed model. © 1986-2012 IEEE.

关键词： Electromagnetic transients

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MRI susceptibility artefacts caused by orthodontic wire

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Dentomaxillofacial Radiology 2024年第6期53卷 396-406页

作者： Iwamoto, Yuri Shimamoto, Hiroaki Felemban, Doaa Terai, Tomoyuki Kreiborg, Sven Mallya, Sanjay M. Yang, Fan-Pei Gloria Tanikawa, Chihiro Murakami, Shumei Department of Oral and Maxillofacial Radiology Osaka University Graduate School of Dentistry Suita 565-0871 Japan Department of Oral Basic and Clinical Sciences College of Dentistry Taibah University Medina 43353 Saudi Arabia Department of Materials Science and Engineering Graduate School of Engineering Osaka University Suita Osaka 565-0871 Japan Department of Pediatric Dentistry and Clinical Genetics School of Dentistry Faculty of Health and Medical Sciences University of Copenhagen Copenhagen DK-2200 Denmark School of Dentistry University of Copenhagen 3D Craniofacial Image Research Laboratory Centre of Head and Orthopedics Copenhagen University Hospital Rigshospitalet Department of Applied Mathematics and Computer Science Technical University of Denmark Copenhagen DK-2200 Denmark Section of Oral and Maxillofacial Radiology UCLA School of Dentistry Los Angeles 90095-1668 CA United States Department of Foreign Languages and Literature National Tsing Hua University Hsinchu 300013 Taiwan Center for Cognition and Mind Sciences National Tsing Hua University Hsinchu 300013 Taiwan Department of Orthodontics and Dentofacial Orthopedics Graduate School of Dentistry Osaka University Suita 565-0871 Japan

Objectives: To evaluate magnetic susceptibility artefacts produced by orthodontic wires on MRI and the influence of wire properties and MRI image sequences on the magnitude of the artefact. Methods: Arch form orthodontic wires [four stainless steels (SS), one cobalt chromium (CC) alloy, 13 titanium (Ti) alloys] were embedded in a polyester phantom, and scanned using a 1.5-T superconducting magnet scanner with an eight-channel phased-array coil. All wires were scanned with T1-weighted spin echo (SE) and gradient echo (GRE) sequences according to the American Society for Testing and Materials (ASTM) F2119-07 standard. The phantom also scanned other eight sequences. Artefacts were measured using the ASTM F2119-07 definition and OsiriX software. Artefact volume was analysed according to metal composition, wire length, number of wires, wire thickness, and imaging sequence as factors. Results: With SE/GRE, black/white artefacts volumes from all SS wires were significantly larger than those produced by CC and Ti wires (P<.01). With the GRE, the black artefacts volume was the highest with the SS wires. With the SE, the black artefacts volume was small, whereas white artefacts were noticeable. The cranio-caudal extent of the artefacts was significantly longer with SS wires (P<.01). Although a direct relationship of wire length, number of wires, and wire thickness with artefact volume was noted, these factors did not influence artefact extension in the cranio-caudal direction. Conclusions: Ferromagnetic/paramagnetic orthodontic wires create artefacts due to local alteration of magnetic field homogeneity. The SS-type wires produced the largest artefacts followed by CC and Ti. © The Author(s) 2024.

关键词： artefacts image sequences magnetic susceptibility MRI orthodontic wire

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Self-supervised contrastive learning of echocardiogram videos enables label-efficient cardiac disease diagnosis

arXiv

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arXiv 2022年

作者： Holste, Gregory Oikonomou, Evangelos K. Mortazavi, Bobak J. Wang, Zhangyang Khera, Rohan Department of Electrical and Computer Engineering The University of Texas at Austin AustinTX United States Section of Cardiovascular Medicine Department of Internal Medicine Yale School of Medicine New HavenCT United States Department of Computer Science & Engineering Texas A&M University College StationTX United States 195 Church St 6th Floor New HavenCT06510 United States

Advances in self-supervised learning (SSL) have shown that self-supervised pretraining on medical imaging data can provide a strong initialization for downstream supervised classification and segmentation. Given the difficulty of obtaining expert labels for medical image recognition tasks, such an "in-domain" SSL initialization is often desirable due to its improved label efficiency over standard transfer learning. However, most efforts toward SSL of medical imaging data are not adapted to video-based medical imaging modalities. With this progress in mind, we developed a self-supervised contrastive learning approach, EchoCLR, catered to echocardiogram videos with the goal of learning strong representations for efficient fine-tuning on downstream cardiac disease diagnosis. EchoCLR leverages (i) distinct videos of the same patient as positive pairs for contrastive learning and (ii) a frame re-ordering pretext task to enforce temporal coherence. When fine-tuned on small portions of labeled data (as few as 51 exams), EchoCLR pretraining significantly improved classification performance for left ventricular hypertrophy (LVH) and aortic stenosis (AS) over other transfer learning and SSL approaches across internal and external test sets. For example, when fine-tuning on 10% of available training data (519 studies), an EchoCLR-pretrained model achieved 0.72 AUROC (95% CI: [0.69, 0.75]) on LVH classification, compared to 0.61 AUROC (95% CI: [0.57, 0.64]) with a standard transfer learning approach. Similarly, using 1% of available training data (53 studies), EchoCLR pretraining achieved 0.82 AUROC (95% CI: [0.79, 0.84]) on severe AS classification, compared to 0.61 AUROC (95% CI: [0.58, 0.65]) with transfer learning. EchoCLR is unique in its ability to learn representations of medical videos and demonstrates that SSL can enable label-efficient disease classification from small, labeled datasets. © 2022, CC BY-NC-ND.

关键词： computer aided diagnosis

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Next-Future: Sample-Efficient Policy Learning for Robotic-Arm Tasks

arXiv

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arXiv 2025年

作者： Özgür, Fikrican Zurbrügg, René Kumar, Suryansh ETH Zürich Switzerland RSL Group ETH Zürich Switzerland Visual Computing and Computational Media Section College of PVFA Department of Electric and Computer Engineering Department of Computer Science and Engineering Texas A&M University College StationTX United States

Hindsight Experience Replay (HER) is widely regarded as the state-of-the-art algorithm for achieving sample-efficient multi-goal reinforcement learning (RL) in robotic manipulation tasks with binary rewards. HER facilitates learning from failed attempts by replaying trajectories with redefined goals. However, it relies on a heuristic-based replay method that lacks a principled framework. To address this limitation, we introduce a novel replay strategy, "Next-Future", which focuses on rewarding single-step transitions. This approach significantly enhances sample efficiency and accuracy in learning multi-goal Markov decision processes (MDPs), particularly under stringent accuracy requirements—a critical aspect for performing complex and precise robotic-arm tasks. We demonstrate the efficacy of our method by highlighting how single-step learning enables improved value approximation within the multi-goal RL framework. The performance of the proposed replay strategy is evaluated across eight challenging robotic manipulation tasks, using ten random seeds for training. Our results indicate substantial improvements in sample efficiency for seven out of eight tasks and higher success rates in six tasks. Furthermore, real-world experiments validate the practical feasibility of the learned policies, demonstrating the potential of "Next-Future" in solving complex robotic-arm tasks. Copyright © 2025, The Authors. All rights reserved.

关键词： Robotic arms

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The enhanced optoelectronic, and thermoelectric nature of novel KXCuS3 (X = Zr, Hf) semiconductors: An inclusive ab-initio study

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Optik 2024年 300卷

作者： Khan, Muhammad Salman Gul, Banat Benabdellah, Ghlamallah Khan, Gulzar Ahmad, Bashir Wabaidur, Saikh Mohammad Tighezza, Ammar M. Ahmad, Hijaz Department of Physics Abdul Wali Khan University Mardan23200 Pakistan Islamabad Pakistan Laboratory of Physical Engineering Department of Physics Faculty of Matter Sciences University of Tiaret 14000 Algeria Department of Chemistry College of Science King Saud University P.O. Box 2455 Riyadh11451 Saudi Arabia Section of Mathematics International Telematic University Uninettuno Corso Vittorio Emanuele II 39 Roma00186 Italy Department of Computer Science and Mathematics Lebanese American University Beirut Lebanon Near East University Operational Research Center in Healthcare TRNC Mersin 10 Nicosia Turkey

The remarkable optoelectronic characteristics of chalcogenides with a quaternary structure have provoked considerable interest, notably due to their potential employment in solar energy conversions. Here we focused on the interaction of light and transport features in novel KXCuS3 (X = Zr, Hf) semiconductors. The calculations involved have employed cutting-edge computational technique that is based on density functional theory. The band profiles results demonstrate that the investigated systems possess direct energy gaps. Likewise, the linear optical features were calculated and discussed for the potential employment of the studied materials in the optoelectronic applications. Beyond the low frequency, the real part of dielectric constant increases as photon energy increases. The electronic transition in these materials possess a higher absorption probability, and as photon energy increases, so does the absorption coefficient. At shorter wavelengths, the refractive indices have an inverse association with extinction coefficients. The significant thermoelectric features too are projected and their remarkable outcomes were deliberated, signifying the compounds as suitable for the thermoelectric devices. The results be significant in expanding the development of resourceful optoelectronics devices and broadening their specific real-world applications. © 2024 Elsevier GmbH

关键词： Refractive index

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Position-Dependent Snap Feedforward: A Gaussian Process Framework

arXiv

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arXiv 2022年

作者： van Haren, Max Poot, Maurice Portegies, Jim Oomen, Tom The Control Systems Technology Section Department of Mechanical Engineering Eindhoven University of Technology Eindhoven Netherlands The Centre for Analysis Scientific Computing and Applications Department of Mathematics and Computer Science Eindhoven University of Technology Eindhoven Netherlands The Delft Center for Systems and Control Delft University of Technology Delft Netherlands

Mechatronic systems have increasingly high performance requirements for motion control. The low-frequency contribution of the flexible dynamics, i.e. the compliance, should be compensated for by means of snap feedforward to achieve high accuracy. Position-dependent compliance, which often occurs in motion systems, requires the snap feedforward parameter to be modeled as a function of position. Position-dependent compliance is compensated for by using a Gaussian process to model the snap feedforward parameter as a continuous function of position. A simulation of a flexible beam shows that a significant performance increase is achieved when using the Gaussian process snap feedforward parameter to compensate for position-dependent compliance. © 2022, CC BY.

关键词： Flexible structures

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EPG2S: Speech Generation and Speech Enhancement based on Electropalatography and Audio Signals using Multimodal Learning

arXiv

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arXiv 2022年

作者： Chen, Li-Chin Chen, Po-Hsun Tsai, Richard Tzong-Han Tsao, Yu Research Center for Information Technology Innovation Academia Sinica 128 Academia Road Section 2 Nankang Taipei115 Taiwan Department of Computer Science and Information Engineering National Central University No. 300 Zhongda Rd. Zhongli District Taoyuan City320317 Taiwan

Speech generation and enhancement based on articulatory movements facilitate communication when the scope of verbal communication is absent, e.g., in patients who have lost the ability to speak. Although various techniques have been proposed to this end, electropalatography (EPG), which is a monitoring technique that records contact between the tongue and hard palate during speech, has not been adequately explored. Herein, we propose a novel multimodal EPG-to-speech (EPG2S) system that utilizes EPG and speech signals for speech generation and enhancement. Different fusion strategies based on multiple combinations of EPG and noisy speech signals are examined, and the viability of the proposed method is investigated. Experimental results indicate that EPG2S achieves desirable speech generation outcomes based solely on EPG signals. Further, the addition of noisy speech signals is observed to improve quality and intelligibility. Additionally, EPG2S is observed to achieve high-quality speech enhancement based solely on audio signals, with the addition of EPG signals further improving the performance. The late fusion strategy is deemed to be the most effective approach for simultaneous speech generation and enhancement. Copyright © 2022, The Authors. All rights reserved.

关键词： Speech enhancement

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