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High-Density 1D Ionic Wire Arrays for Osmotic Energy Conversion
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作者 Jinlin Hao Cuncai Lin +7 位作者 Min Zhao Yilin Wang Xingteng Ma Lilong Gao Xin Sui Longcheng Gao Kunyan Sui Lei Jiang 《Nano-Micro Letters》 2026年第4期540-549,共10页
Osmotic energy,existing between the seawater and river water,is a renewable energy source,which can be directly converted into electricity by ion-exchange membranes(IEM).In traditional IEMs,the ion transport channels ... Osmotic energy,existing between the seawater and river water,is a renewable energy source,which can be directly converted into electricity by ion-exchange membranes(IEM).In traditional IEMs,the ion transport channels are formed by nanophase separation of hydrophilic ion carriers and hydrophobic segments.It is difficult to realize high-density ion channels with controlled spatial arrangement and length scale of ion carriers.Herein,we construct high-density 1D ion wires as transmission channels.Through molecular design,hydrophilic imidazole groups and hydrophobic alkyl tails were introduced into the repeat units,which self-assembled into 1D ion transporting core and protecting shell along the main chains.The areal density of the ionic wire arrays is up to~10^(12)cm^(-2),which is the highest value.The ionic wires ensure both high ion flux transport and high selectivity,achieving an ultrahigh-power density of 40.5 W m^(-2)at a 500-fold salinity gradient.Besides,the ionic wire array membrane is well recyclable and antibacterial.The ionic wires provide novel concept for next generation of high-performance membranes. 展开更多
关键词 One-Dimensional ionic wire SELF-ASSEMBLY high-density ion channels Ultrahigh ion-exchange capacity Anti-swelling
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Obstacles to Vaccination against COVID-19 among the Population Living in the Kindu Health Zone
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作者 Antoine Lufimbo Katawandja Jimmy Yuma Ilemba +1 位作者 Imani Ramazani Bin Eradi Simon-Decap Mabakutuvangilanga Ntela 《Journal of Biosciences and Medicines》 2025年第2期230-242,共13页
Introduction: Vaccination faces several obstacles in the fight against COVID-19, yet it has been identified as one of the most effective means of preventing new epidemics of COVID-19. The aim was to contribute to impr... Introduction: Vaccination faces several obstacles in the fight against COVID-19, yet it has been identified as one of the most effective means of preventing new epidemics of COVID-19. The aim was to contribute to improving vaccination coverage against COVID-19 in the Kindu health zone. Method: We conducted a cross-sectional descriptive study with an analytical focus, using a questionnaire that enabled us to carry out a survey from October 03 to 30, 2022. Our target study population was residents of the Kindu health zone. A total of 420 subjects participated in our study, including 42 per site. Results: The study revealed a low proportion of vaccinated subjects (38.3%) and a high proportion of non-vaccinated subjects (61.70%). Non-belief in the efficacy of vaccines (p = 0.001), infodemia (p = 0.001) and respect for ethnic norms (p = 0.001) were identified as perceived barriers to vaccination. Fear of being branded with the “666” beast badge (p = 0.004) as the perceived severity. Respondents’ perceptions of mass vaccination against COVID-19 are mixed, and their opinions and expectations of COVID-19 vaccination in the town of Kindu are divided. Conclusion: In order to increase the proportion of people vaccinated against COVID-19, it is suggested here to increase the population’s ability to detect false information through a well-structured communication and health education program. 展开更多
关键词 COVID-19 VACCINATION obstacles Kindu
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A Base Station Deployment Algorithm for Wireless Positioning Considering Dynamic Obstacles
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作者 Aiguo Li Yunfei Jia 《Computers, Materials & Continua》 2025年第3期4573-4591,共19页
In the context of security systems,adequate signal coverage is paramount for the communication between security personnel and the accurate positioning of personnel.Most studies focus on optimizing base station deploym... In the context of security systems,adequate signal coverage is paramount for the communication between security personnel and the accurate positioning of personnel.Most studies focus on optimizing base station deployment under the assumption of static obstacles,aiming to maximize the perception coverage of wireless RF(Radio Frequency)signals and reduce positioning blind spots.However,in practical security systems,obstacles are subject to change,necessitating the consideration of base station deployment in dynamic environments.Nevertheless,research in this area still needs to be conducted.This paper proposes a Dynamic Indoor Environment Beacon Deployment Algorithm(DIE-BDA)to address this problem.This algorithm considers the dynamic alterations in obstacle locations within the designated area.It determines the requisite number of base stations,the requisite time,and the area’s practical and overall signal coverage rates.The experimental results demonstrate that the algorithm can calculate the deployment strategy in 0.12 s following a change in obstacle positions.Experimental results show that the algorithm in this paper requires 0.12 s to compute the deployment strategy after the positions of obstacles change.With 13 base stations,it achieves an effective coverage rate of 93.5%and an overall coverage rate of 97.75%.The algorithm can rapidly compute a revised deployment strategy in response to changes in obstacle positions within security systems,thereby ensuring the efficacy of signal coverage. 展开更多
关键词 Wireless positioning base station deployment dynamic obstacles dynamic obstacle wireless positioning
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Topology transformation of the zeolite catalysts to enhance electronic metal-support interactions and hydrogen spillover effects for hydrogenation of aromatic-rich oil to high-density aviation fuels
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作者 Xiaoqi Zhang Kai Meng +10 位作者 He Liu Bernard Wiafe Biney Yiqiang Qi Kunyu Xu Jiang Wu Liying Xie Xiaoyu Li Yueliang Liu Kun Chen Zongxian Wang Aijun Guo 《Journal of Energy Chemistry》 2025年第7期1026-1037,共12页
Metal-support interactions and hydrogen spillover effects in heterogeneous catalysts play a crucial role in aromatic hydrogenation reactions;however,these effects are limited by the metal dispersion on the catalyst an... Metal-support interactions and hydrogen spillover effects in heterogeneous catalysts play a crucial role in aromatic hydrogenation reactions;however,these effects are limited by the metal dispersion on the catalyst and the number of acceptable H*receptors.This study prepares highly dispersed Ni nanoparticles(NPs)catalysts on a Beta substrate via precursor structure topology transformation.In contrast to traditional support materials,the coordination and electronic structure changes between the Ni NPs and the support were achieved,further optimizing the active interface sites and enhancing hydrogen activation and hydrogenation performance.Additionally,the-OH groups at the strong acid sites in zeolite effectively intensified the hydrogen spillover effect as receptors for H^(*)migration and anchoring,accelerating the hydrogenation rate of aromatic rings.Under solvent-free conditions,this catalyst was used for the hydrogenation reaction of aromatic-rich oils,directly producing a C_(8)-C_(14)branched cycloalkanes mixture with an aromatic conversion rate of>99%.The cycloalkanes mixture produced by this method features high density(0.92 g/mL)and a low freezing point(<-60℃),making it suitable for use as high-density aviation fuel or as an additive to enhance the volumetric heat value of conventional aviation fuels in practical applications. 展开更多
关键词 Metal-support interaction Hydrogen spillover ZEOLITE Aromatic-richoil high-density aviation fuels
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Application of high-density electrical resistivity tomography in backfilling effectiveness of quarries:A case study of Liuyao Village quarry in Huaibei City,Anhui Province
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作者 XU Guangrui LIU Lijia HAN Jiangtao 《Global Geology》 2025年第4期231-239,共9页
Evaluation of backfilling effectiveness plays a crucial role in the geological environment management and restoration of abandoned open-pit quarries,providing a scientific basis for subsequent greening efforts.Backfil... Evaluation of backfilling effectiveness plays a crucial role in the geological environment management and restoration of abandoned open-pit quarries,providing a scientific basis for subsequent greening efforts.Backfill soil,predominantly composed of silty clay,demonstrates high water retention capacity and elevated moisture content,leading to a pronounced resistivity contrast with the bedrock exposed by quarrying activities.To investigate the distribution of backfill soil subsurface and assess backfilling effectiveness in the study area,this study conducted a comprehensive geophysical investigation utilizing the high-density electrical resistivity tomography(ERT).A total of 19 ERT survey lines were deployed across three distinct areas in Liuyao Village,Huaibei City,Anhui Province,China.The inversion results,derived from both two-dimensional(2D)and three-dimensional(3D),reveal distinct electrical properties of the subsurface materials:the backfill soil layer shows low resistivity features,the fill stone layer exhibits medium to high resistivity,and the bedrock shows the highest resistivity.The 2D inversion results,from the data measured using the Wenner array effectively capture the spatial distribution and structural features of the backfill soil layer.The findings indicate a gradual east-west thinning of the clay layer within the quarry.Furthermore,the northern pit area exhibits a uniform distribution of backfill soil layer,indicative of effective backfilling operations.In contrast,the southern pit area lacks a well-defined clay layer,suggesting suboptimal backfilling effectiveness. 展开更多
关键词 high-density electrical resistivity tomography Wenner array backfilling effectiveness backfill soil
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Preparation and Characterization of Multilayered High-density Polyethylene with Tunable Crystalline Structure
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作者 Yi-Jie Ma Jia-Wei Gong +4 位作者 Bin Chen Ying Zhang Gan-Ji Zhong Zhong-Ming Li Xue-Qin Gao 《Chinese Journal of Polymer Science》 2025年第9期1616-1628,I0011,共14页
In rotationally extruded fittings,high-density polyethylene(HDPE)pipes prepared using conventional processing methods often suffer from poor pressure resistance and low toughness.This study introduces an innovative ro... In rotationally extruded fittings,high-density polyethylene(HDPE)pipes prepared using conventional processing methods often suffer from poor pressure resistance and low toughness.This study introduces an innovative rotary shear system(RSS)to address these deficiencies through controlled mandrel rotation and cooling rates.We successfully prepared self-reinforced HDPE pipes with a three-layer structure combining spherical and shish-kebab crystals.Rotational processing aligned the molecular chains in the ring direction and formed shish-kebab crystals.As a result,the annular tensile strength of the rotationally processed three-layer shish-kebab structure(TSK)pipe increased from 26.7 MPa to 76.3 MPa,an enhancement of 185.8%.Notably,while maintaining excellent tensile strength(73.4 MPa),the elongation at break of the spherulite shishkebab spherulite(SKS)tubes was improved to 50.1%,as compared to 33.8%in the case of shish-kebab spherulite shish-kebab(KSK)tubes.This improvement can be attributed to the changes in the micro-morphology and polymer structure within the SKS tubes,specifically due to the formation of small-sized shish-kebab crystals and the low degrees of interlocking.In addition,2D-SAXS analysis revealed that KSK tubes have higher tensile strength due to smaller crystal sizes and larger shish dimensions,forming dense interlocking structures.In contrast,the SKS and TSK tubes had thicker amorphous regions and smaller shish sizes,resulting in reduced interlocking and mechanical performance. 展开更多
关键词 high-density polyethylene pipe SHISH-KEBAB Circumferential tensile strength Rotational shear Multilayer structure
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3D laser structuring of supermetalphobic microstructures inside elastomer for multilayer high-density interconnect soft electronics
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作者 Chengjun Zhang Qing Yang +5 位作者 Haoyu Li Zexiang Luo Yu Lu Jialiang Zhang Cheng Li Feng Chen 《International Journal of Extreme Manufacturing》 2025年第3期337-348,共12页
High-density interconnect(HDI)soft electronics that can integrate multiple individual functions into one miniaturized monolithic system is promising for applications related to smart healthcare,soft robotics,and human... High-density interconnect(HDI)soft electronics that can integrate multiple individual functions into one miniaturized monolithic system is promising for applications related to smart healthcare,soft robotics,and human-machine interactions.However,despite the recent advances,the development of three-dimensional(3D)soft electronics with both high resolution and high integration is still challenging because of the lack of efficient manufacturing methods to guarantee interlayer alignment of the high-density vias and reliable interlayer electrical conductivity.Here,an advanced 3D laser printing pathway,based on femtosecond laser direct writing(FLDW),is demonstrated for preparing liquid metal(LM)-based any layer HDI soft electronics.FLDW technology,with the characteristics of high spatial resolution and high precision,allows the maskless fabrication of high-resolution embedded LM microchannels and high-density vertical interconnect accesses for 3D integrated circuits.High-aspect-ratio blind/through LM microstructures are formed inside the elastomer due to the supermetalphobicity induced during laser ablation.The LM-based HDI circuit featuring high resolution(~1.5μm)and high integration(10-layer electrical interconnection)is achieved for customized soft electronics,including various customized multilayer passive electric components,soft multilayer circuit,and cross-scale multimode sensors.The 3D laser printing method provides a versatile approach for developing chip-level soft electronics. 展开更多
关键词 3D soft electronics liquid metal high-density interconnection femtosecond laser direct writing supermetalphobicity
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Enhancing strength at elevated temperatures via dynamic high-density mobile dislocations in Mg alloys
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作者 Mingyu Fan Ye Cui +13 位作者 Xin Zhou Junming Chen Yang Zhang Lixin Sun Jamieson Brechtl Daqing Fang Qian Li Qingqing Ding Hongbin Bei Peter K.Liaw Yanzhuo Xue Xun-Li Wang Yang Lu Zhongwu Zhang 《Journal of Magnesium and Alloys》 2025年第8期3768-3783,共16页
Dislocation strengthening,as one of the methods to simultaneously enhance the room temperature strength and ductility of alloys,does not achieve the desired strengthening and plasticity effect during elevated-temperat... Dislocation strengthening,as one of the methods to simultaneously enhance the room temperature strength and ductility of alloys,does not achieve the desired strengthening and plasticity effect during elevated-temperature deformation.Here,we report a novel strategy to boost the dislocation multiplication and accumulation during deformation at elevated temperatures through dynamic strain aging(DSA).With the introduction of the rare-earth element Ho in Mg-Y-Zn alloy,Ho atoms diffuse toward dislocations during deformation at elevated temperatures,provoking the DSA effect,which increases the dislocation density significantly via the interactions of mobile dislocations and Ho atoms.The resulting alloy achieves a great enhancement of dislocation hardening and obtains the dual benefits of high strength and good ductility simultaneously at high homologous temperatures.The present work provides an effective strategy to enhancing the strength and ductility for elevated-temperature materials. 展开更多
关键词 Mg-Y-Zn alloy Ho addition high-density mobile dislocations Dynamic strain aging(DSA) Elevated-temperature strength
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Transcriptomic Analysis of Polygonatum sibiricum in Response to Continuous Cropping Obstacles
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作者 Zhufang WU Yong CHEN 《Agricultural Biotechnology》 2025年第2期6-9,12,共5页
[Objectives]This study was conducted to comprehensively understand the changes in gene expression of plants under environmental stress during different growth and development stages.[Methods]The effects of continuous ... [Objectives]This study was conducted to comprehensively understand the changes in gene expression of plants under environmental stress during different growth and development stages.[Methods]The effects of continuous cropping on the roots and leaves of Polygonatum sibiricum were investigated using transcriptome sequencing.Normally-grown first crop P.sibiricum was used as the control group,while continuous cropping plants served as the treatment group.Transcriptomic differences in roots and leaves under different conditions were compared.[Results]The leaf materials of first crop and continuous cropping P.sibiricum(CCLZ vs FCLZ)showed 21916 differentially expressed genes(DEGs),while the root materials of first crop and continuous cropping P.sibiricum(CCRZ vs FCRZ)exhibited 12726 DEGs(the lowest DEG count)(12726).Among them,1896 DEGs were common.GO enrichment analysis revealed that DEGs were mainly enriched in metabolism,cell wall degradation,and pathogen defense.KEGG enrichment analysis indicated that DEGs in CCLZ vs FCLZ and CCRZ vs FCRZ primarily affected hormone signal transduction and pathogen interaction pathways.[Conclusions]This study preliminarily elucidate the regulatory mechanisms in the roots and leaves of continuous cropping P.sibiricum at the molecular level,providing reference for research on its adaptation to continuous cropping. 展开更多
关键词 Polygonatum sibiricum Continuous cropping obstacle TRANSCRIPTOME Differentially expressed gene Functional analysis
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Ecological Space Planning and Management in High-Density Construction Areas:A Case Study of Jinjiang City
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作者 WANG Bin 《Journal of Landscape Research》 2025年第5期23-27,共5页
In the context of rapid urbanization,high-density construction areas face significant challenges,including the reduction of ecological spaces and the deterioration of their functions.Planning and managing ecological s... In the context of rapid urbanization,high-density construction areas face significant challenges,including the reduction of ecological spaces and the deterioration of their functions.Planning and managing ecological spaces have emerged as essential strategies to address the conflict between urban development and ecological conservation.Using Jinjiang City,Fujian Province as the case study,this paper systematically examines the significance and primary challenges of ecological space planning in highdensity construction areas.It also identifies prevailing issues within the current research domain,including“an overemphasis on top-level design at the expense of implementation,a focus on isolated aspects rather than systemic integration,and prioritization of control over coordination”.This study proposes the key aspects of ecological space planning and management in high-density construction areas,focusing on three fundamental dimensions:human-centered demand orientation,the integration of top-down and bottomup linkage mechanisms,and a differentiated control system.Drawing on the full-element assessment of the ecosystem,ecological network construction,and full-process control system implemented in Jinjiang City,an integrated approach to ecological space governance,encompassing assessment,planning,and control,has been developed.This approach offers both theoretical insights and practical guidance for optimizing ecological spaces in comparable urban contexts. 展开更多
关键词 high-density construction areas Ecological space planning Ecological management and control Jinjiang City Ecological network
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Association between uric acid to high-density lipoprotein ratio and mental health symptoms in people with type 2 diabetes
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作者 Hui Xu Dong-Juan He +6 位作者 Cheng Luo Xian-Mei Yu Cheng-Zheng Duan Da Sun De-Jun Wu Xiao-Qiang Mao Wei-Feng Jiang 《World Journal of Diabetes》 2025年第10期249-260,共12页
BACKGROUND The association between the uric acid-to-high-density lipoprotein cholesterol ratio(UHR)and mental health among individuals with type 2 diabetes mellitus(T2DM)has not been thoroughly investigated.AIM To exa... BACKGROUND The association between the uric acid-to-high-density lipoprotein cholesterol ratio(UHR)and mental health among individuals with type 2 diabetes mellitus(T2DM)has not been thoroughly investigated.AIM To examine the link between UHR and symptoms of depression and anxiety in patients with T2DM.METHODS A cross-sectional analysis was carried out from March 2023 to April 2024,involving participants diagnosed with T2DM.Data on sociodemographic characteristics,clinical parameters,and UHR values were systematically gathered.The Self-Rating Depression Scale(SDS)and Self-Rating Anxiety Scale(SAS)were utilized to evaluate depressive and anxiety symptoms,respectively.To assess the relationships between UHR and SDS/SAS scores,linear regression models were employed,incorporating adjustments for potential confounding variables.Additionally,smooth curve fitting and threshold effect analyses were conducted to explore potential nonlinear relationships.RESULTS A total of 285 patients with T2DM were included.Initial univariate analysis demonstrated a significant positive correlation between elevated UHR levels and higher SDS and SAS scores.Multivariate regression analysis revealed that a one-unit rise in UHR was associated with a 1.13-point increase in SDS scores(95%CI:0.69-1.58)and a 0.57-point increase in SAS scores(95%CI:0.20-0.93).After controlling for confounders,UHR remained positively correlated with SDS(β=1.55,95%CI:0.57-2.53)and SAS(β=0.72,95%CI:0.35-1.09).Nonlinear analysis identified critical thresholds at UHR values of 5.02 for SDS and 4.00 for SAS,beyond which the relationships between UHR and psychological symptom scores became markedly stronger(P<0.05).CONCLUSION Higher UHR levels are significantly linked to exacerbated depressive and anxiety symptoms in patients with T2DM.These results indicate that UHR may function as a promising biomarker to identify individuals at greater risk of mental health complications within this population. 展开更多
关键词 ANXIETY DEPRESSION Type 2 diabetes mellitus Uric acid high-density lipoprotein cholesterol Uric acid-to-highdensity lipoprotein cholesterol ratio
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Construction of a high-density genetic map to explore the genetic regulation of erucic acid, oleic acid, and linolenic acid contents in Brassica juncea
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作者 Wei Yan Jinze Zhang +5 位作者 Yingfen Jiang Kunjiang Yu Qian Wang Xu Yang Lijing Xiao Entang Tian 《Journal of Integrative Agriculture》 2025年第6期2171-2189,共19页
Rapeseed mustard(Brassica juncea L.) is the third most important oilseed crop in the world, but the geneticmechanism underlying its massive phenotypic variation remains largely unexplored. In this study, specific leng... Rapeseed mustard(Brassica juncea L.) is the third most important oilseed crop in the world, but the geneticmechanism underlying its massive phenotypic variation remains largely unexplored. In this study, specific length amplified fragment sequencing(SLAF-Seq) was used to resequence a population comprising 197 F8recombinantinbred lines(RILs) derived from a cross between vegetable-type Qichi881 and oilseed-type YufengZC of B. juncea. In total, 438,895 high-quality SLAFs were discovered, 47,644 of which were polymorphic, and 3,887 of the polymorphic markers met the requirements for genetic map construction. The final map included 3,887 markers on 18 linkage groups and was 1,830.23 centiMorgan(cM) in length, with an average distance of 0.47 cM between adjacent markers. Using the newly constructed high-density genetic map, a total of 53 QTLs for erucicacid(EA), oleic acid(OA), and linolenic acid(LNA) were detected and integrated into eight consensus QTLswith two for each of these traits. For each of these three traits, two candidate genes were cloned and sequence analysis indicated colocalization with their respective consensus QTLs. The co-dominant allele-specific markers for Bju.FAD3.A03 and Bju.FAD3.B07 were developed and showed co-localization with their consensus QTLs andco-segregation with LNA content, further supporting the results of QTL mapping and bioinformatic analysis. Theexpression levels of the cloned homologous genes were also determined, and the genes were tightly correlatedwith the EA, OA and LNA contents of different lines. The results of this study will facilitate the improvement offatty acid traits and molecular breeding of B. juncea. Further uses of the high-density genetic map created in this study are also discussed. 展开更多
关键词 Brassica juncea high-density genetic map Bju.FAE1 Bju.FAD2 Bju.FAD3
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Prediction of Self-Care Behaviors in Patients Using High-Density Surface Electromyography Signals and an Improved Whale Optimization Algorithm-Based LSTM Model
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作者 Shuai Huang Dan Liu +4 位作者 Youfa Fu Jiadui Chen Ling He Jing Yan Di Yang 《Journal of Bionic Engineering》 2025年第4期1963-1984,共22页
Stroke survivors often face significant challenges when performing daily self-care activities due to upper limb motor impairments.Traditional surface electromyography(sEMG)analysis typically focuses on isolated hand p... Stroke survivors often face significant challenges when performing daily self-care activities due to upper limb motor impairments.Traditional surface electromyography(sEMG)analysis typically focuses on isolated hand postures,overlooking the complexity of object-interactive behaviors that are crucial for promoting patient independence.This study introduces a novel framework that combines high-density sEMG(HD-sEMG)signals with an improved Whale Optimization Algorithm(IWOA)-optimized Long Short-Term Memory(LSTM)network to address this limitation.The key contributions of this work include:(1)the creation of a specialized HD-sEMG dataset that captures nine continuous self-care behaviors,along with time and posture markers,to better reflect real-world patient interactions;(2)the development of a multi-channel feature fusion module based on Pascal’s theorem,which enables efficient signal segmentation and spatial–temporal feature extraction;and(3)the enhancement of the IWOA algorithm,which integrates optimal point set initialization,a diversity-driven pooling mechanism,and cosine-based differential evolution to optimize LSTM hyperparameters,thereby improving convergence and global search capabilities.Experimental results demonstrate superior performance,achieving 99.58%accuracy in self-care behavior recognition and 86.19%accuracy for 17 continuous gestures on the Ninapro db2 benchmark.The framework operates with low latency,meeting the real-time requirements for assistive devices.By enabling precise,context-aware recognition of daily activities,this work advances personalized rehabilitation technologies,empowering stroke patients to regain autonomy in self-care tasks.The proposed methodology offers a robust,scalable solution for clinical applications,bridging the gap between laboratory-based gesture recognition and practical,patient-centered care. 展开更多
关键词 Self-care behaviors high-density surface electromyography(HD-sEMG) Long Short-Term Memory(LSTM)network Multi-channel feature fusion
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Association Between the Uric Acid to High-Density Lipoprotein Ratio and Carotid Atherosclerosis in Patients with T2DM
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作者 Yao Yin Zi-yun Feng +2 位作者 Li-yin Zhang Jiao-yue Zhang Si Jin 《Current Medical Science》 2025年第6期1436-1446,共11页
Objective Uric acid(UA)to high-density lipoprotein(HDL)ratio(UHR)has recently been proposed as a novel biomarker of inflammation.This study aimed to investigate the association between the UHR and carotid atherosclero... Objective Uric acid(UA)to high-density lipoprotein(HDL)ratio(UHR)has recently been proposed as a novel biomarker of inflammation.This study aimed to investigate the association between the UHR and carotid atherosclerosis(CAS)in patients with type 2 diabetes mellitus(T2DM).Methods In this single-center,retrospective cross-sectional study,379 patients with T2DM were enrolled and categorized into two groups:259 T2DM patients with CAS(T2DM-CAS)and 120 T2DM patients without CAS(T2DM-WCAS).Carotid intima‒media thickness(CIMT)and carotid atheromatous plaques(CAPs)were assessed via Doppler ultrasound.UHR values were compared between the groups,and receiver operating characteristic(ROC)curve analysis was employed to evaluate their diagnostic performance.Results The UHR was significantly greater in the T2DM-CAS group than in the T2DM-WCAS group(P<0.001).Multivariate logistic regression analysis identified the UHR as an independent risk factor for T2DM-CAS(P<0.001).The area under the ROC curve(AUC)for UHR to detect CAS was 0.750,with an optimal cut-off value of 0.35.Conclusion The UHR is an independent risk factor for CAS in patients with T2DM and may serve as a valuable biomarker for predicting CAS in this population. 展开更多
关键词 Uric acid to high-density lipoprotein ratio(UHR) Type 2 diabetes mellitus(T2DM) Carotid atheromatous plaque BIOMARKER Carotid atherosclerosis Carotid intima-media thickness Cardiovascular risk
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Imitation Learning for Unmanned Aerial Vehicle Obstacle Avoidance Based on Visual Features with DAgger
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作者 Yuqi Yang Mengyun Wang +1 位作者 Yifeng Niu Bo Wang 《Journal of Beijing Institute of Technology》 2026年第1期114-126,共13页
Unmanned aerial vehicles(UAVs)face the challenge of autonomous obstacle avoidance in complex,multi-obstacle environments.Behavior cloning offers a promising approach to rapidly acquire a learning policy from limited e... Unmanned aerial vehicles(UAVs)face the challenge of autonomous obstacle avoidance in complex,multi-obstacle environments.Behavior cloning offers a promising approach to rapidly acquire a learning policy from limited expert demonstrations.However,pure imitation learning inherently suffers from poor exploration and limited generalization,typically necessitating extensive datasets to train competent student policies.We utilize a cross-modal variational autoencoder(CM-VAE)to extract compact features from raw visual inputs and UAV states,which then feed into a policy network.We evaluated our approach in a simulated environment featuring a challenging circular trajectory with eight gate obstacles.The results demonstrate that the policy trained with pure behavior cloning consistently failed.In stark contrast,our DAgger-augmented behavior cloning method successfully traversed all gates without collision.Our findings confirm that DAgger effectively mitigates the shortcomings of behavior cloning,enabling the creation of reliable and sample-efficient navigation policies for UAVs. 展开更多
关键词 imitation learning unmanned aerial vehicle obstacle avoidance DAGGER
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Design of a Patrol and Security Robot with Semantic Mapping and Obstacle Avoidance System Using RGB-D Camera and LiDAR
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作者 Shu-Yin Chiang Shin-En Huang 《Computers, Materials & Continua》 2026年第4期1735-1753,共19页
This paper presents an intelligent patrol and security robot integrating 2D LiDAR and RGB-D vision sensors to achieve semantic simultaneous localization and mapping(SLAM),real-time object recognition,and dynamic obsta... This paper presents an intelligent patrol and security robot integrating 2D LiDAR and RGB-D vision sensors to achieve semantic simultaneous localization and mapping(SLAM),real-time object recognition,and dynamic obstacle avoidance.The system employs the YOLOv7 deep-learning framework for semantic detection and SLAM for localization and mapping,fusing geometric and visual data to build a high-fidelity 2D semantic map.This map enables the robot to identify and project object information for improved situational awareness.Experimental results show that object recognition reached 95.4%mAP@0.5.Semantic completeness increased from 68.7%(single view)to 94.1%(multi-view)with an average position error of 3.1 cm.During navigation,the robot achieved 98.0%reliability,avoided moving obstacles in 90.0%of encounters,and replanned paths in 0.42 s on average.The integration of LiDAR-based SLAMwith deep-learning–driven semantic perception establishes a robust foundation for intelligent,adaptive,and safe robotic navigation in dynamic environments. 展开更多
关键词 RGB-D semantic mapping object recognition obstacle avoidance security robot
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Research on unmanned swarm scheduling strategies for mountain obstacle-breaching missions
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作者 WANG Kaisheng HUANG Yanyan +1 位作者 TAN Jinxi ZHAI Wenjie 《Journal of Systems Engineering and Electronics》 2026年第1期26-35,共10页
In response to the challenges faced by unmanned swarms in mountain obstacle-breaching missions within complex terrains,such as poor task-resource coupling,lengthy solution generation times,and poor inter-platform coll... In response to the challenges faced by unmanned swarms in mountain obstacle-breaching missions within complex terrains,such as poor task-resource coupling,lengthy solution generation times,and poor inter-platform collaboration,an unmanned swarm scheduling strategy tailored is proposed for mountain obstacle-breaching missions.Initially,by formalizing the descriptions of obstacle breaching operations,the swarm,and obstacle targets,an optimization model is constructed with the objectives of expected global benefit,timeliness,and task completion degree.A meta-task decomposition and reassembly strategy is then introduced to more precisely match the capabilities of unmanned platforms with task requirements.Additionally,a meta-task decomposition optimization model and a meta-task allocation operator are incorporated to achieve efficient allocation of swarm resources and collaborative scheduling.Simulation results demonstrate that the model can accurately generate reasonable and feasible obstacle breaching execution plans for unmanned swarms based on specific task requirements and environmental conditions.Moreover,compared to conventional strategies,the proposed strategy enhances task completion degree and expected returns while reducing the execution time of the plans. 展开更多
关键词 mountain obstacle breaching unmanned swarm task scheduling META-TASK
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DFCOA:Distributed Formation Control and Obstacle Avoidance for Multi-UGV Systems
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作者 Md.Faishal Rahaman Xueyuan Li +3 位作者 Muhammad Amjad Ibrahim Gasimove Md.Shariful Islam S.M.Abul Bashar 《Computer Modeling in Engineering & Sciences》 2026年第2期922-954,共33页
Researchers are increasingly focused on enabling groups of multiple unmanned vehicles to operate cohesively in complex,real-world environments,where coordinated formation control and obstacle avoidance are essential f... Researchers are increasingly focused on enabling groups of multiple unmanned vehicles to operate cohesively in complex,real-world environments,where coordinated formation control and obstacle avoidance are essential for executing sophisticated collective tasks.This paper presents a Distributed Formation Control and Obstacle Avoidance(DFCOA)framework for multi-unmanned ground vehicles(UGV).DFCOA integrates a virtual leader structure for global guidance,an improved A^(*)path planning algorithm with an advanced cost function for efficient path planning,and a repulsive-force-based improved vector field histogram star(VFH^(*))technique for collision avoidance.The virtual leader generates a reference trajectory while enabling distributed execution;the improved A^(*)algorithm reduces planning time and number of nodes to determine the shortest path from the starting position to the goal;and the improved VFH^(*)uses 2D LiDAR data with inter-agent repulsive force to simultaneously avoid collision with obstacles and maintain safe inter-vehicle distances.The formation stability of the proposed DFCOA reaches 95.8%and 94.6%in two scenarios,with root mean square(RMS)centroid errors of 0.9516 and 1.0008 m,respectively.Velocity tracking is precise(velocity centroid error RMS of 0.2699 and 0.1700 m/s),and linear velocities closely match the desired 0.3 m/s.Safety metrics showed average collision risks of 0.7773 and 0.5143,with minimum inter-vehicle distances of 0.4702 and 0.8763 m,confirming collision-free navigation of four UGVs.DFCOA outperforms conventional methods in formation stability,path efficiency,and scalability,proving its suitability for decentralized multi-UGV applications. 展开更多
关键词 Formation control obstacle avoidance virtual leader path planning multi UGV collaboration
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A Bio-inspired Bubble Artificial Muscles and TacTip Perception-driven Tri-legged Robot for Obstacle Avoidance
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作者 Chaoqun Xiang Zhengwei Zhong +3 位作者 Wenqiang Wu Xiaocong Chen Yisheng Guan Tao Zou 《Journal of Bionic Engineering》 2026年第1期175-191,共17页
Legged robots have considerable potential for traversing unstructured situations;nonetheless,their inflexible frameworks often constrain adaptability and obstacle negotiation.The study article presents a revolutionary... Legged robots have considerable potential for traversing unstructured situations;nonetheless,their inflexible frameworks often constrain adaptability and obstacle negotiation.The study article presents a revolutionary Soft Tri-Legged Robot(STLR)that improves movement and obstacle-avoidance skills by using a bio-inspired pneumatic artificial muscle(Bubble Artificial Muscles)and a bio-inspired tactile sensor(TacTip).The STLR is activated by BAMs,which are flexible,pneu-matic-driven actuators that provide fine control over forward,backward,and steering movements.Obstacle identification and avoidance are facilitated by the TacTip sensor,which delivers tactile input for traversing unstructured terrains.We delineate the mechanical features of the BAMs,assess the functionality of the robot's legs,and elaborate on the incorpora-tion of the tactile sensing system.Experimental results demonstrate that the STLR can effectively achieve multi-directional flexible movement and obstacle avoidance through a cross-modal perception-actuation mechanism.This study highlights the promise of soft robotics for search and rescue,medical aid,and autonomous exploration,while delineating difficulties and opportunities for future improvements in functionality and efficiency. 展开更多
关键词 Legged robot Bio-inspired bubble artificial muscles Bio-inspired TacTip sensor Foot tactile perception obstacle avoidance
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Zero-Shot Vision-Based Robust 3D Map Reconstruction and Obstacle Detection in Geometry-Deficient Room-Scale Environments
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作者 Taehoon Kim Sehun Lee Junho Ahn 《Computers, Materials & Continua》 2026年第2期602-631,共30页
As large,room-scale environments become increasingly common,their spatial complexity increases due to variable,unstructured elements.Consequently,demand for room-scale service robots is surging,yet most technologies r... As large,room-scale environments become increasingly common,their spatial complexity increases due to variable,unstructured elements.Consequently,demand for room-scale service robots is surging,yet most technologies remain corridor-centric,and autonomous navigation in expansive rooms becomes unstable even around static obstacles.Existing approaches face several structural limitations.These include the labor-intensive requirement for large-scale object annotation and continual retraining,as well as the vulnerability of vanishing point or linebased methods when geometric cues are insufficient.In addition,the high cost of LiDAR and 3D perception errors caused by limited wall cues and dense interior clutter further limit their effectiveness.To address these challenges,we propose a zero-shot vision-based algorithm for robust 3D map reconstruction in geometry-deficient room-scale environments.The algorithm operates in three layers:Layer 1 performs dimension-wise boundary detection;Layer 2 estimates vanishing points,refines the precise perspective space,and extracts a floor mask;and Layer 3 conducts 3D spatial mapping and obstacle recognition.The proposed method was experimentally validated across various geometric-deficient room-scale environments,including lobbies,seminar rooms,conference rooms,cafeterias,and museums—demonstrating its ability to reliably reconstruct 3D maps and accurately recognize obstacles.Experimental results show that the proposed algorithm achieved an F1 score of 0.959 in precision perspective space detection and 0.965 in floor mask extraction.For obstacle recognition and classification,it obtained F1 scores of 0.980 in obstacle absent areas,0.913 in solid obstacle environments,and 0.939 in skeleton-type sparse obstacle environments,confirming its high precision and reliability in geometric-deficient room-scale environments. 展开更多
关键词 Spatial AI zero-shot learning geometric deficiency 3D map reconstruction room-scale environment sparse obstacle precise classification
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