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A Novel Semi-Supervised Multi-View Picture Fuzzy Clustering Approach for Enhanced Satellite Image Segmentation
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作者 Pham Huy Thong Hoang Thi Canh +2 位作者 Nguyen Tuan Huy Nguyen Long Giang Luong Thi Hong Lan 《Computers, Materials & Continua》 2026年第3期1092-1117,共26页
Satellite image segmentation plays a crucial role in remote sensing,supporting applications such as environmental monitoring,land use analysis,and disaster management.However,traditional segmentation methods often rel... Satellite image segmentation plays a crucial role in remote sensing,supporting applications such as environmental monitoring,land use analysis,and disaster management.However,traditional segmentation methods often rely on large amounts of labeled data,which are costly and time-consuming to obtain,especially in largescale or dynamic environments.To address this challenge,we propose the Semi-Supervised Multi-View Picture Fuzzy Clustering(SS-MPFC)algorithm,which improves segmentation accuracy and robustness,particularly in complex and uncertain remote sensing scenarios.SS-MPFC unifies three paradigms:semi-supervised learning,multi-view clustering,and picture fuzzy set theory.This integration allows the model to effectively utilize a small number of labeled samples,fuse complementary information from multiple data views,and handle the ambiguity and uncertainty inherent in satellite imagery.We design a novel objective function that jointly incorporates picture fuzzy membership functions across multiple views of the data,and embeds pairwise semi-supervised constraints(must-link and cannot-link)directly into the clustering process to enhance segmentation accuracy.Experiments conducted on several benchmark satellite datasets demonstrate that SS-MPFC significantly outperforms existing state-of-the-art methods in segmentation accuracy,noise robustness,and semantic interpretability.On the Augsburg dataset,SS-MPFC achieves a Purity of 0.8158 and an Accuracy of 0.6860,highlighting its outstanding robustness and efficiency.These results demonstrate that SSMPFC offers a scalable and effective solution for real-world satellite-based monitoring systems,particularly in scenarios where rapid annotation is infeasible,such as wildfire tracking,agricultural monitoring,and dynamic urban mapping. 展开更多
关键词 Multi-view clustering satellite image segmentation semi-supervised learning picture fuzzy sets remote sensing
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Multi-View Picture Fuzzy Clustering:A Novel Method for Partitioning Multi-View Relational Data 被引量:1
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作者 Pham Huy Thong Hoang Thi Canh +2 位作者 Luong Thi Hong Lan Nguyen Tuan Huy Nguyen Long Giang 《Computers, Materials & Continua》 2025年第6期5461-5485,共25页
Multi-view clustering is a critical research area in computer science aimed at effectively extracting meaningful patterns from complex,high-dimensional data that single-view methods cannot capture.Traditional fuzzy cl... Multi-view clustering is a critical research area in computer science aimed at effectively extracting meaningful patterns from complex,high-dimensional data that single-view methods cannot capture.Traditional fuzzy clustering techniques,such as Fuzzy C-Means(FCM),face significant challenges in handling uncertainty and the dependencies between different views.To overcome these limitations,we introduce a new multi-view fuzzy clustering approach that integrates picture fuzzy sets with a dual-anchor graph method for multi-view data,aiming to enhance clustering accuracy and robustness,termed Multi-view Picture Fuzzy Clustering(MPFC).In particular,the picture fuzzy set theory extends the capability to represent uncertainty by modeling three membership levels:membership degrees,neutral degrees,and refusal degrees.This allows for a more flexible representation of uncertain and conflicting data than traditional fuzzy models.Meanwhile,dual-anchor graphs exploit the similarity relationships between data points and integrate information across views.This combination improves stability,scalability,and robustness when handling noisy and heterogeneous data.Experimental results on several benchmark datasets demonstrate significant improvements in clustering accuracy and efficiency,outperforming traditional methods.Specifically,the MPFC algorithm demonstrates outstanding clustering performance on a variety of datasets,attaining a Purity(PUR)score of 0.6440 and an Accuracy(ACC)score of 0.6213 for the 3 Sources dataset,underscoring its robustness and efficiency.The proposed approach significantly contributes to fields such as pattern recognition,multi-view relational data analysis,and large-scale clustering problems.Future work will focus on extending the method for semi-supervised multi-view clustering,aiming to enhance adaptability,scalability,and performance in real-world applications. 展开更多
关键词 Multi-view clustering picture fuzzy sets dual anchor graph fuzzy clustering multi-view relational data
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Laser stealth dicing ofβ-Ga_(2)O_(3):Theoretical and experimental studies 被引量:1
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作者 Zhanpeng Sun Junjie Zou +8 位作者 Rui Li Zhaofu Zhang Junqi Mai Zijun Qi David Vazquez Cortes Qijun Wang Gai Wu Wei Shen Sheng Liu 《Journal of Materials Science & Technology》 2025年第35期303-312,共10页
Gallium oxide(Ga_(2)O_(3))is an ultra-wide bandgap semiconductor with excellent potential for high-power and ultraviolet optoelectronic device applications.High-performance Ga_(2)O_(3)-based high-power devices rely he... Gallium oxide(Ga_(2)O_(3))is an ultra-wide bandgap semiconductor with excellent potential for high-power and ultraviolet optoelectronic device applications.High-performance Ga_(2)O_(3)-based high-power devices rely heavily on precise processing,especially in wafer dicing.Laser stealth dicing(LSD)is an innova-tive laser technology that utilizes a focused laser to create subsurface modifications in the wafer without surface damage.LSD has broad application prospects in the field of semiconductor precision processing.In this work,the idea of achieving high-quality dicing ofβ-Ga_(2)O_(3) wafers via LSD was proposed.A com-bination of atomistic simulations and experiments was used to understand the underlying mechanism of LSD ofβ-Ga_(2)O_(3) wafers.On the one hand,the laser loading and fracture process ofβ-Ga_(2)O_(3) wafers were simulated using molecular dynamics(MD)methods as well as a machine learning potential.The effects of single-pulse energy on LSD were analyzed through the lattice residual pressure,the final total energy of the system,the internal atomic strain,and the maximum stress value during uniaxial tension.On the other hand,based on the MD simulations,LSD was successfully performed onβ-Ga_(2)O_(3) wafers along three main crystal planes in the laboratory,resulting in good surface quality.This work not only provides profound optimization strategies for the LSD process ofβ-Ga_(2)O_(3),establishing the foundation for high-quality dicing ofβ-Ga_(2)O_(3) wafers,but also verifies the accuracy of MD simulations in predict-ing trends related to the LSD,offering a potential approach for high-quality dicing of other materials in future research. 展开更多
关键词 β-Ga_(2)O_(3) Laser stealth dicing High-quality wafer dicing Molecular dynamics Machine learning potential
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Construction of a Marketing System for Leveled Mathematics Readers from a User-Oriented Perspective: A Strategy Optimization Study Based on the 4V Marketing Model
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作者 Zhaoyong Ouyang Guanlin Liu 《Proceedings of Business and Economic Studies》 2025年第5期39-44,共6页
In the context of the continuous deepening of the“Double Reduction”policy and the growing demand for quality education,leveled mathematics readers,as an emerging form of publishing that integrates subject education ... In the context of the continuous deepening of the“Double Reduction”policy and the growing demand for quality education,leveled mathematics readers,as an emerging form of publishing that integrates subject education and reading experience,face challenges such as unclear leveling logic,insufficient functional support,and weak user engagement.This paper introduces the 4V marketing theory and constructs an analytical framework from four dimensions:differentiation,functionality,added value,and resonance.Two representative products,“Climbing Mathematics”and“Spark Mathematics,”are selected for a typical case comparison to identify their strengths and weaknesses in content design,service systems,and brand operation,and to extract transferable strategic elements.The study finds that the user-value-oriented strategy based on the 4V model can effectively address the core issues in the market promotion and user relationship building of leveled mathematics readers,providing practical paths and theoretical support for educational publishing institutions to achieve product innovation and brand upgrading in this niche field. 展开更多
关键词 4V marketing theory Leveled mathematics readers Educational publishing Typical case analysis Marketing strategy
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Correlation between human embryo morphokinetics and pregnancy outcomes on Asian infertility women:A retrospective cohort study
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作者 Hop Vu Dinh Cuong An Manh +3 位作者 Anh Phi Thi Tu Huong Nguyen Thi Lien Hoang Le Hanh Nguyen Van 《Asian pacific Journal of Reproduction》 2025年第3期140-142,共3页
Selecting the embryo with the highest implantation potential is a top priority in in-vitro fertilization(IVF)centers.Few studies have explored the relationship between day 5 blastocyst morphokinetics and implantation ... Selecting the embryo with the highest implantation potential is a top priority in in-vitro fertilization(IVF)centers.Few studies have explored the relationship between day 5 blastocyst morphokinetics and implantation outcomes[1].Despite numerous time-lapse studies,the findings often conflict due to differences in patient demographics,lab conditions,and protocols,such as oxygen concentration[2].Thus,there is ongoing debate regarding which parameters are most predictive of implantation. 展开更多
关键词 vitro fertilization BLASTOCYST lab conditions time lapse studies human embryo morphokinetics implantation potential Asian infertility women pregnancy outcomes
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Robust Real-Time Analysis of Cow Behaviors Using Accelerometer Sensors and Decision Trees with Short Data Windows and Misalignment Compensation
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作者 Duc-Nghia Tran Viet-Manh Do +1 位作者 Manh-Tuyen Vi Duc-Tan Tran 《Computers, Materials & Continua》 2025年第5期2525-2553,共29页
This study focuses on the design and validation of a behavior classification system for cattle using behavioral data collected through accelerometer sensors.Data collection and behavioral analysis are achieved using m... This study focuses on the design and validation of a behavior classification system for cattle using behavioral data collected through accelerometer sensors.Data collection and behavioral analysis are achieved using machine learning(ML)algorithms through accelerometer sensors.However,behavioral analysis poses challenges due to the complexity of cow activities.The task becomes more challenging in a real-time behavioral analysis system with the requirement for shorter data windows and energy constraints.Shorter windows may lack sufficient information,reducing algorithm performance.Additionally,the sensor’s position on the cowsmay shift during practical use,altering the collected accelerometer data.This study addresses these challenges by employing a 3-s data window to analyze cow behaviors,specifically Feeding,Lying,Standing,and Walking.Data synchronization between accelerometer sensors placed on the neck and leg compensates for the lack of information in short data windows.Features such as the Vector of Dynamic Body Acceleration(VeDBA),Mean,Variance,and Kurtosis are utilized alongside the Decision Tree(DT)algorithm to address energy efficiency and ensure computational effectiveness.This study also evaluates the impact of sensor misalignment on behavior classification.Simulated datasets with varying levels of sensor misalignment were created,and the system’s classification accuracy exceeded 0.95 for the four behaviors across all datasets(including original and simulated misalignment datasets).Sensitivity(Sen)and PPV for all datasets were above 0.9.The study provides farmers and the dairy industry with a practical,energy-efficient system for continuously monitoring cattle behavior to enhance herd productivity while reducing labor costs. 展开更多
关键词 Monitoring behavior classification ACCELEROMETER sensor MISALIGNMENT leg-mounted neck-mounted COW
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CGB-Net:A Novel Convolutional Gated Bidirectional Network for Enhanced Sleep Posture Classification
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作者 Hoang-Dieu Vu Duc-Nghia Tran +2 位作者 Quang-TuPham Ngoc-Linh Nguyen Duc-Tan Tran 《Computers, Materials & Continua》 2025年第11期2819-2835,共17页
This study presents CGB-Net,a novel deep learning architecture specifically developed for classifying twelve distinct sleep positions using a single abdominal accelerometer,with direct applicability to gastroesophagea... This study presents CGB-Net,a novel deep learning architecture specifically developed for classifying twelve distinct sleep positions using a single abdominal accelerometer,with direct applicability to gastroesophageal reflux disease(GERD)monitoring.Unlike conventional approaches limited to four basic postures,CGB-Net enables fine-grained classification of twelve clinically relevant sleep positions,providing enhanced resolution for personalized health assessment.The architecture introduces a unique integration of three complementary components:1D Convolutional Neural Networks(1D-CNN)for efficient local spatial feature extraction,Gated Recurrent Units(GRU)to capture short-termtemporal dependencieswith reduced computational complexity,and Bidirectional Long Short-Term Memory(Bi-LSTM)networks for modeling long-term temporal context in both forward and backward directions.This complementary integration allows the model to better represent dynamic and contextual information inherent in the sensor data,surpassing the performance of simpler or previously published hybrid models.Experiments were conducted on a benchmark dataset consisting of 18 volunteers(age range:19–24 years,mean 20.56±1.1 years;height 164.78±8.18 cm;weight 55.39±8.30 kg;BMI 20.24±2.04),monitored via a single abdominal accelerometer.A subjectindependent evaluation protocol with multiple random splits was employed to ensure robustness and generalizability.The proposed model achieves an average Accuracy of 87.60% and F1-score of 83.38%,both reported with standard deviations over multiple runs,outperforming several baseline and state-of-the-art methods.By releasing the dataset publicly and detailing themodel design,this work aims to facilitate reproducibility and advance research in sleep posture classification for clinical applications. 展开更多
关键词 Sleep posture classification deep learning accelerometer gastroesophageal reflux disease(GERD) CGB-Net convolutional neural networks recurrent neural networks human activity recognition
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X-ray microcomputed tomography of 3D chaotic microcavities
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作者 Ke Tian Mohammed Zia Jalaludeen +2 位作者 Yeon Ui Lee Shilong Li Síle Nic Chormaic 《Advanced Photonics Nexus》 2025年第6期56-63,共8页
Chaotic microcavities play a crucial role in several research areas,including the study of unidirectional microlasers,nonlinear optics,sensing,quantum chaos,and non-Hermitian physics.To date,most theoretical and exper... Chaotic microcavities play a crucial role in several research areas,including the study of unidirectional microlasers,nonlinear optics,sensing,quantum chaos,and non-Hermitian physics.To date,most theoretical and experimental explorations have focused on two-dimensional(2D)chaotic dielectric microcavities,but there have been minimal studies on three-dimensional(3D)ones because precise geometrical information of a 3D microcavity can be difficult to obtain.Here,we image 3D microcavities with submicron resolution using X-ray microcomputed tomography(μCT),enabling nondestructive imaging that preserves the sample for subsequent use.By analyzing the ray dynamics of a typical deformed microsphere,we demonstrate that a sufficient deformation along all three dimensions can lead to chaotic ray trajectories over extended time scales.Notably,using the X-rayμCT reconstruction results,the phase space chaotic ray dynamics of a deformed microsphere are accurately established.X-rayμCT could become a unique platform for the characterization of such deformed 3D microcavities by providing a precise means for determining the degree of deformation necessary for potential applications in ray chaos and quantum chaos. 展开更多
关键词 chaotic microcavity whispering gallery resonator X-ray microcomputed tomography ray dynamics
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Relationship between gastric mucosal atrophy by endoscopy and non-ampullary duodenal epithelial tumors
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作者 Kazuya Ohno Eiji Nakatani +10 位作者 Takafumi Kurokami Asami Kawai Ryosuke Itai Masanori Matsuda Yuichi Masui Tatsunori Satoh Shinya Ikeda Taiyo Hirata Shodai Takeda Makoto Suzuki Ken Haruma 《World Journal of Gastrointestinal Oncology》 2025年第2期84-92,共9页
BACKGROUND The pathogenesis of non-ampullary duodenal epithelial tumors(NADETs)is not fully understood.NADETs that express gastric-type mucin phenotypes(GNADETs)are noteworthy because of their high malignancy.Gastric ... BACKGROUND The pathogenesis of non-ampullary duodenal epithelial tumors(NADETs)is not fully understood.NADETs that express gastric-type mucin phenotypes(GNADETs)are noteworthy because of their high malignancy.Gastric foveolar metaplasia,from which G-NADETs originate,protects the duodenal mucosa from gastric acidity.As gastric acid secretion is affected by endoscopic gastric mucosal atrophy(EGMA),we hypothesized that EGMA would be associated with GNADETs.AIM To evaluate the association between EGMA and the occurrence of G-NADETs.METHODS This cross-sectional retrospective study investigated the relationship between EGMA and NADETs in 134 patients.The duodenum was divided into parts 1(bulb),2(superior duodenal angle to the papilla),and 3(anal side of the papilla to the horizontal part).The effects of gastric acidity and presence of Brunner’s glands were considered.EGMA was divided into types C(no or mild atrophy)and O(severe atrophy).Mucin phenotype expressions in NADETs were divided into gastric,intestinal,gastrointestinal,and unclassifiable.RESULTS When NADETs were classified according to EGMA,105 were classified as type C and 29 as type O.G-NADETs were present in 11.9%(16 cases)of all cases,and all 16 cases were of type C.Among G-NADETs,93.8%(15 cases)were present in part 1 or 2.There was an association between G-NADETs and type C in part 1,and 50.0%(eight of 16 cases)of G-NADETs were associated with a current or previous Helicobacter pylori infection status.Additionally,all eight cases occurred in part 1.CONCLUSION G-NADETs were significantly associated with type C.Gastric acidity and Brunner's gland growth may be associated with G-NADETs. 展开更多
关键词 Gastric acidity Gastric foveolar metaplasia Gastric mucosal atrophy Helicobacter pylori Mucin phenotype Nonampullary duodenal epithelial tumor
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An Innovative Semi-Supervised Fuzzy Clustering Technique Using Cluster Boundaries
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作者 Duong Tien Dung Ha Hai Nam +1 位作者 Nguyen Long Giang Luong Thi Hong Lan 《Computers, Materials & Continua》 2025年第12期5341-5357,共17页
Active semi-supervised fuzzy clustering integrates fuzzy clustering techniques with limited labeled data,guided by active learning,to enhance classification accuracy,particularly in complex and ambiguous datasets.Alth... Active semi-supervised fuzzy clustering integrates fuzzy clustering techniques with limited labeled data,guided by active learning,to enhance classification accuracy,particularly in complex and ambiguous datasets.Although several active semi-supervised fuzzy clustering methods have been developed previously,they typically face significant limitations,including high computational complexity,sensitivity to initial cluster centroids,and difficulties in accurately managing boundary clusters where data points often overlap among multiple clusters.This study introduces a novel Active Semi-Supervised Fuzzy Clustering algorithm specifically designed to identify,analyze,and correct misclassified boundary elements.By strategically utilizing labeled data through active learning,our method improves the robustness and precision of cluster boundary assignments.Extensive experimental evaluations conducted on three types of datasets—including benchmark UCI datasets,synthetic data with controlled boundary overlap,and satellite imagery—demonstrate that our proposed approach achieves superior performance in terms of clustering accuracy and robustness compared to existing active semi-supervised fuzzy clustering methods.The results confirm the effectiveness and practicality of our method in handling real-world scenarios where precise cluster boundaries are critical. 展开更多
关键词 Clustering algorithms semi-supervised classification active learning fuzzy clustering boundary elements boundary identification boundary correction
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Unraveling the Morphological and Energetic Properties of 2PACz Self-Assembled Monolayers Fabricated With Upscaling Deposition Methods
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作者 Silvia Mariotti Ilhem Nadia Rabehi +13 位作者 Congyang Zhang Xiaomin Huo Jiahao Zhang Penghui Ji Tianhao Wu Tongtong Li Shuai Yuan Xiaomin Liu Ting Guo Chenfeng Ding Hengyuan Wang Annalisa Bruno Luis K.Ono Yabing Qi 《Energy & Environmental Materials》 2025年第2期291-304,共14页
Self-assembled monolayers(SAMs)are widely used as hole transport materials in inverted perovskite solar cells,offering low parasitic absorption and suitability for semitransparent and tandem solar cells.While SAMs hav... Self-assembled monolayers(SAMs)are widely used as hole transport materials in inverted perovskite solar cells,offering low parasitic absorption and suitability for semitransparent and tandem solar cells.While SAMs have shown to be promising in small-area devices(≤1 cm^(2)),their application in larger areas has been limited by a lack of knowledge regarding alternative deposition methods beyond the common spin-coating approach.Here,we compare spin-coating and upscalable methods such as thermal evaporation and spray-coating for[2-(9H-carbazol-9-yl)ethyl]phosphonic acid(2PACz),one of the most common carbazole-based SAMs.The impact of these deposition methods on the device performance is investigated,revealing that the spray-coating technique yields higher device performance.Furthermore,our work provides guidelines for the deposition of SAM materials for the fabrication of perovskite solar modules.In addition,we provide an extensive characterization of 2PACz films focusing on thermal evaporation and spray-coating methods,which allow for thicker 2PACz deposition.It is found that the optimal 2PACz deposition conditions corresponding to the highest device performances do not always correlate with the monolayer characteristics. 展开更多
关键词 2PACz EVAPORATION Perovskite solar cells Self-assembled monolayer Spray-coating
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Analysis of characteristics and influencing factors of agricultural carbon emission in Jiangxi Province,southeast China
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作者 Shuai Fu Yingxiang Feng +5 位作者 Jie Yu Yaobin Liu Bingxian Xu Shenyi Liu Linyang Liu Zhili Yang 《International Journal of Agricultural and Biological Engineering》 2025年第6期168-174,共7页
With the continuous economic development and population growth,carbon emissions from farmland utilization cannot be underestimated.In this study,the life cycle assessment method was employed to determine the accountin... With the continuous economic development and population growth,carbon emissions from farmland utilization cannot be underestimated.In this study,the life cycle assessment method was employed to determine the accounting boundaries and sources of carbon emissions from cultivated land use.A STIRPAT model and a carbon emissions accounting system from cultivated land utilization were developed to explore the characteristics and influencing factors of carbon emissions in Jiangxi Province.Additionally,targeted countermeasures were proposed to promote low-carbon utilization of cultivated land in the region.The results show that the total carbon emission underwent four distinct stages:“steady growth,fluctuating growth,rapid decline,and leveling off”.Specifically,carbon emissions decreased from 220.2 t in 1990 to 17.8 t in 2019.In terms of carbon emission intensity,the overall trend is downward,with the intensity dropping below 7 t/hm2 after 2009.The number of agricultural population,total agricultural machinery power,and rural investment were identified as significant driving factors for carbon emissions from cultivated land utilization in Jiangxi Province.Conversely,land productivity and investment in science and technology exhibited inhibitory effects on carbon emission growth.Enhancing technological investment and improving land productivity were found to be conducive to promoting low-carbon utilization of cultivated land in Jiangxi. 展开更多
关键词 cultivated land utilization STIRPAT model carbon emission accounting driving factors
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Hidden Biodiversity in the Tropical Rain Forests:Two New Species of Leptobrachella Smith 1925 (Anura:Megophryidae) from Vietnam
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作者 Van Chung HOANG The Cuong PHAM +4 位作者 Quang Tien PHAN Trong Dang DO Bin WANG Jianping JIANG Quang Truong NGUYEN 《Asian Herpetological Research》 2025年第2期169-191,共23页
Two new species of Leptobrachella are described from Vietnam based on morphological differences and genetic divergences in 16S rRNA mitochondrial gene sequences.The new taxa are distinguished from each other and from ... Two new species of Leptobrachella are described from Vietnam based on morphological differences and genetic divergences in 16S rRNA mitochondrial gene sequences.The new taxa are distinguished from each other and from other species of the genus Leptobrachella in body size,head width/length ratio,tympanum morphology,dorsal skin texture,the presence/absence of fringes on toes,color of dorsal and ventral body,and iris color.The two new species are also divergent from each other and from other congeners by a 4.14% or greater uncorrected genetic distance.Leptobrachella batxatensis sp.nov.is genetically closest to L.shiwandashanensis and L.wuhuangmontis from China.Leptobrachella duyenae sp.nov.is genetically closest to L.bidoupensis from Vietnam with strong nodal support from both BI and ML analyses(1.0/99%). 展开更多
关键词 16S rRNA mitochondrial gene Leptobrachella batxatensis sp.nov. Leptobrachella duyenae sp.nov. morphology taxonomy
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Numerical Analysis of Pressure Propagation Emitted by Collapse of a Single Cavitation Bubble near an Oscillating Wall
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作者 Quang-Thai Nguyen Duong Ngoc Hai +3 位作者 The-Duc Nguyen Van-Tu Nguyen Jinyul Hwang Warn-Gyu Park 《Computer Modeling in Engineering & Sciences》 2025年第12期3433-3452,共20页
This study presents a numerical analysis of the effects of a rigid flat wall with oscillating motion on the pressure wave propagation during a single spherical cavitation bubble collapse at different initial bubble po... This study presents a numerical analysis of the effects of a rigid flat wall with oscillating motion on the pressure wave propagation during a single spherical cavitation bubble collapse at different initial bubble positions.Different nondimensional distances S=0.8,0.9,1.0,1.1,1.2 and 1.3 were considered to investigate the effects of initial in-phase and out-of-phase oscillations of the flat wall.Numerical simulations of cavitation bubble collapse near an oscillating wall were conducted using a compressible two-phase flow model.This model incorporated the Volume of Fluid(VOF)interface-sharpening technique on a general curvilinear moving grid.The numerical results were consistent with published experimental data.The simulation examined the impact of oscillating walls on bubble behavior and the resulting pressure peaks observed on the wall surface.The numerical results demonstrate the significant impact of wall oscillation conditions on bubble collapse and migration behavior,and consequently,the generation of pressure waves with significantly different propagation and pressure peaks induced by shock impact on the rigid wall.Different behaviors were observed in the trendlines of the pressure peaks and maximum jet velocity under in-phase and out-of-phase oscillating walls,with distinct values.At S≥1.0,a higher-pressure peak on the wall was observed in the case of the out-of-phase oscillating condition,whereas a higher-pressure peak was found in the case of the in-phase condition at S<1.0.The highest-pressure peak was found at S=0.8 in trend lines of in-phase and S=1.1 in trend lines of out-of-phase oscillation effects. 展开更多
关键词 Pressure propagation numerical analysis cavitation bubble collapse oscillating wall effects
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An Active Safe Semi-Supervised Fuzzy Clustering with Pairwise Constraints Based on Cluster Boundary
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作者 Duong Tien Dung Ha Hai Nam +1 位作者 Nguyen Long Giang Luong Thi Hong Lan 《Computers, Materials & Continua》 2025年第12期5625-5642,共18页
Semi-supervised clustering techniques attempt to improve clustering accuracy by utilizing a limited number of labeled data for guidance.This method effectively integrates prior knowledge using pre-labeled data.While s... Semi-supervised clustering techniques attempt to improve clustering accuracy by utilizing a limited number of labeled data for guidance.This method effectively integrates prior knowledge using pre-labeled data.While semi-supervised fuzzy clustering(SSFC)methods leverage limited labeled data to enhance accuracy,they remain highly susceptible to inappropriate or mislabeled prior knowledge,especially in noisy or overlapping datasets where cluster boundaries are ambiguous.To enhance the effectiveness of clustering algorithms,it is essential to leverage labeled data while ensuring the safety of the previous knowledge.Existing solutions,such as the Trusted Safe Semi-Supervised Fuzzy Clustering Method(TS3FCM),struggle with random centroid initialization,fixed neighbor radius formulas,and handling outliers or noise at cluster overlaps.A new framework called Active Safe Semi-Supervised Fuzzy Clustering with Pairwise Constraints Based on Cluster Boundary(AS3FCPC)is proposed in this paper to deal with these problems.It does this by combining pairwise constraints and active learning.AS3FCPC uses active learning to query only the most informative data instances close to the cluster boundaries.It also uses pairwise constraints to enforce the cluster structure,which makes the system more accurate and robust.Extensive test results on diverse datasets,including challenging noisy and overlapping scenarios,demonstrate that AS3FCPC consistently achieves superior performance compared to state-of-the-art methods like TS3FCM and other baselines,especially when the data is noisy and overlaps.This significant improvement underscores AS3FCPC’s potential for reliable and accurate semisupervised fuzzy clustering in complex,real-world applications,particularly by effectively managing mislabeled data and ambiguous cluster boundaries. 展开更多
关键词 Active learning safe semi-supervised fuzzy clustering confidence weight boundary identification pairwise constraints
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A Hybrid Deep Learning Method for Forecasting Reservoir Water Level from Sentinel-2 Satellite Images
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作者 Hoang Thi Minh Chau Tran Thi Ngan +2 位作者 Nguyen Long Giang Tran Manh Tuan Tran Kim Chau 《Computers, Materials & Continua》 2025年第6期4915-4937,共23页
Global climate change,along with the rapid increase of the population,has put significant pressure on water security.A water reservoir is an effective solution for adjusting and ensuring water supply.In particular,the... Global climate change,along with the rapid increase of the population,has put significant pressure on water security.A water reservoir is an effective solution for adjusting and ensuring water supply.In particular,the reservoir water level is an essential physical indicator for the reservoirs.Forecasting the reservoir water level effectively assists the managers in making decisions and plans related to reservoir management policies.In recent years,deep learning models have been widely applied to solve forecasting problems.In this study,we propose a novel hybrid deep learning model namely the YOLOv9_ConvLSTM that integrates YOLOv9,ConvLSTM,and linear interpolation to predict reservoir water levels.It utilizes data from Sentinel-2 satellite images,generated from visible spectrum bands(Red-Blue-Green)to reconstruct true-color reservoir images.Adam is used as the optimization algorithm with the loss function being MSE(Mean Squared Error)to evaluate the model’s error during training.We implemented and validated the proposed model using Sentinel-2 satellite imagery for the An Khe reservoir in Vietnam.To assess its performance,we also conducted comparative experiments with other related models,including SegNet_ConvLSTM and UNet_ConvLSTM,on the same dataset.The model performances were validated using k-fold cross-validation and ANOVA analysis.The experimental results demonstrate that the YOLOv9_ConvLSTM model outperforms the compared models.It has been seen that the proposed approach serves as a valuable tool for reservoir water level forecasting using satellite imagery that contributes to effective water resource management. 展开更多
关键词 YOLOv9 ConvLSTM reservoir water level forecasting satellite images
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Rediscovery and Revision of the Diagnostic Characters of Opisthotropis daovantieni Orlov, Darevsky, and Murphy, 1998(Squamata:Natricidae)from Southern Vietnam, with Notes on its Hemipenial Morphology and Defensive Behavior
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作者 Zongyuan GAO Yong ZHANG +4 位作者 Vu Dang Hoang NGUYEN Ke JIANG Tao Thien NGUYEN Jiatang LI Jinlong REN 《Asian Herpetological Research》 2025年第1期49-65,共17页
The Tien's Mountain Stream Snake,Opisthotropis daovantieni Orlov, Darevsky, and Murphy, 1998, has been represented solely by its type series, with no additional specimens reported in the past two decades. As a res... The Tien's Mountain Stream Snake,Opisthotropis daovantieni Orlov, Darevsky, and Murphy, 1998, has been represented solely by its type series, with no additional specimens reported in the past two decades. As a result, limited data exist and O. daovantieni remains one of the least studied members of its genus. Based on a re-examination of the type series, analysis of newly collected topotypic specimens, and a review of museum collections, this study provides an updated and comprehensive morphological characterization of O. daovantieni including detailed descriptions of hemipenial morphology, revised diagnostic characters,phylogenetic positioning, and ecological insights.Based on morphological comparisons with congeners, we also define the informal Opisthotropis spenceri group to facilitate future taxonomic work. In addition, this study documents a previously unreported defensive behavior involving tail-poking,observed in the field and thus far unique within the genus Opisthotropis. 展开更多
关键词 diagnostic characters HEMIPENIS Opisthotropis spenceri group sulcus spermaticus tail-poking behavior
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Direct Observation of Early-Stage Polymer Crystallization Driven by Surface Wrinkling and Compressive Stress in Thin Films
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作者 Peng Zhang Stephan V.Roth +1 位作者 Peter Muller-Buschbaum Tian-Bai He 《Chinese Journal of Polymer Science》 2025年第2期360-367,共8页
The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surfa... The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surface wrinkling precedes nucleation and crystal growth.This study examined the relationship between surface wrinkling,nucleation,and the formation of crystalline supramolecular structures using atomic force microscopy(AFM)and X-ray scattering measurements.Surface wrinkling is attributed to curving induced by accumulated stresses,including residual stress from the sample preparation and thermal stress during cooling.These stresses cause large-scale material flow and corresponding changes in the molecular conformations,potentially reducing the nucleation barrier.This hypothesis is supported by the rapid crystal growth observed following the spread of surface wrinkles.Additionally,the surface curving of the polymer thin film creates local minima of the free energy,facilitating nucleation.The nuclei subsequently grow into crystalline supramolecular structures by incorporating polymer molecules from the melt.This mechanism highlights the role of localized structural inhomogeneity in the early stages of crystallization and provides new insights into structure formation processes. 展开更多
关键词 Polymer crystallization NUCLEATION Surface wrinkling Stress Thin film
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Taxonomic revision of the critically endangered big-headed turtles(Reptilia:Testudines:Platysternidae Gray,1869),with description of a new species
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作者 Qian-Ru Liang Jia-Xuan Li +7 位作者 Yan Ge Jun-Man Ou You-Qiang Yin Chatmongkon Suwannapoom Minh Le Truong Quang Nguyen Uwe Fritz Shi-Ping Gong 《Zoological Research》 2025年第5期1047-1058,共12页
The big-headed turtle(Platysternon megacephalum),currently the only extant member of the genus Platysternon and the family Platysternidae,has undergone severe population declines driven by poaching,illegal trade,and h... The big-headed turtle(Platysternon megacephalum),currently the only extant member of the genus Platysternon and the family Platysternidae,has undergone severe population declines driven by poaching,illegal trade,and habitat loss,leading to its classification as Critically Endangered(CR)by the International Union for Conservation of Nature(IUCN).Despite its conservation status,persistent taxonomic ambiguities and unresolved phylogenetic relationships have hindered effective protection and management.This study integrated evidence from genome-wide single nucleotide polymorphisms(SNPs),mitochondrial DNA sequences(COI,12S),and morphological data to reconstruct the phylogeny and phylogeography of Platysternon and revise its taxonomy.Results revealed that Platysternon megacephalum megacephalum and Platysternon megacephalum peguense represent deeply divergent evolutionary lineages,which are herein recognized as distinct species,Platysternon megacephalum Gray,1831 sensu stricto and Platysternon peguense Gray,1870.The subspecies Platysternon megacephalum shiui Ernst&McCord,1987 is taxonomically invalid.In addition,a highly divergent lineage endemic to the Baise-Hechi region of Guangxi is described as a third species,Platysternon baiseensis sp.nov.This revised taxonomic framework resolves key phylogenetic relationships and delineates species boundaries,establishing a robust systematic foundation for big-headed turtles and providing a critical taxonomic basis for future conservation efforts targeting this endangered group of turtles. 展开更多
关键词 Asia Integrative Taxonomy Phylogeny Platysternidae Platysternon baiseensis sp.nov.
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Unconventional superconductivity inCr-based nitride La_(3)Cr_(10-x)N_(11)
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作者 M Y Zou J C Jiao +10 位作者 K W Chen C Y Jiang C S Chen X Li Q Wu N Y Zhang O O Bernal P C Ho A Koda D E MacLaughlin L Shu 《Chinese Physics B》 2025年第11期214-221,共8页
Magnetization,specific heat,and muon spin relaxation(μSR)experiments have been carried out on the Cr-based nitride superconductor La_(3)Cr_(10-x)N_(11),which exhibits a number of unconventional superconducting proper... Magnetization,specific heat,and muon spin relaxation(μSR)experiments have been carried out on the Cr-based nitride superconductor La_(3)Cr_(10-x)N_(11),which exhibits a number of unconventional superconducting properties.The susceptibilityχ(T)shows nearly perfect superconducting diamagnetism(4πχ(T=0)≈-1)and a remarkably high upper critical fieldμ_(0)Hc_(2)=11.2 T.The specific heat displays activated exponential behavior exp(-Δ0/kBT),together with a large and field-dependent residual Sommerfeld coefficient.Transverse-field muon spin relaxation(μSR)measurements suggest s+s-wave or p-wave pairing symmetry,ruling out single s-wave pairing.Zero-fieldμSR yields no statistically significant evidence for time reversal symmetry breaking(TRSB),and places an upper bound of 1.5(1.3)ms-1 on any TRSB-induced muon relaxation rate at T=0.Our results suggest that the unconventional superconductivity in Ln_(3)Cr_(10-x)N_(11),Ln=La and Pr,is mainly due to Cr 3d electrons and is similar in both compounds,whereas Pr 4f electrons are primarily responsible for the TRSB superconductivity observed in Pr_(3)Cr_(10-x)N_(11). 展开更多
关键词 muon spin relaxation/rotation heavy fermion superconductor chromium-based superconductor
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