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Overcoming photovoltage deficit via phenylthiourea derivatives for efficient printed perovskite solar cells with enhanced stability
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作者 Jinlong Hu Runxin Li +5 位作者 Qiongfeng Zhan Jiajun Qin Dadong Wen Bing Yi Huisheng Peng Zhihang Tang 《Journal of Semiconductors》 2026年第2期111-118,共8页
Although the certified power conversion efficiency(PCE)of single-junction perovskite solar cells(PSCs)has achieved a high level of 27%,approaching the single-crystalline silicon solar cells,the device stability remain... Although the certified power conversion efficiency(PCE)of single-junction perovskite solar cells(PSCs)has achieved a high level of 27%,approaching the single-crystalline silicon solar cells,the device stability remains an urgent issue to be resolved for the commercialization.Defect passivation emerged as a viable approach to enhance the operational stability of the solar devices.Herein,phenylthiourea(PhTu)derivatives are selected as effective passivation agents to enhance the optoelectronic properties of printed methylammonium lead iodide(MAPbI_(3))films.It is demonstrated that incorporating a small amount of 1-(4-carboxyphenyl)-2-thiourea(PhTu-COOH)significantly reduces the trap-state density and leads to longer carrier lifetime of the perovskite films.As a result,the inverted solar device made of Ph Tu-COOH-modified MAPbI_(3) perovskite film shows remarkably improved efficiency(from 17.29%to 20.22%)and obviously increased open-circuit voltage(V_(OC))(from 1.043 to 1.143 V),as compared with the pristine device.Moreover,the Ph Tu-COOH-modified PSCs exhibit enhanced operational stability due to the significantly reduced trap-state density.Finally,the optimized solar module fabricated with an active area of 11.28 cm^(2) delivers a high PCE of 17.07%with negligible V_(OC)loss,demonstrating the feasibility of the blade-coating method for large-area perovskite film deposition. 展开更多
关键词 PHENYLTHIOUREA defect passivation printable high efficiency perovskite solar cell
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Dynamic control of crystallization rate enables efficient sodium storage in coal-based hard carbon:Synergistic effects of short-range ordered structure and closed pores
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作者 Rui Li Anjun Hu +9 位作者 Zhen Wang Wei Yang Qin He Weiyue Li Liangzhi Li Wei Jiao Beilei Yuan Jian Chen Fei Li Jianping Long 《Journal of Energy Chemistry》 2026年第1期832-841,I0018,共11页
Coal-derived hard carbon(HC)represents a promising anode material for sodium-ion batteries owing to its cost-effectiveness and high carbon yield.However,conventional carbonization induces excessive graphitization,yiel... Coal-derived hard carbon(HC)represents a promising anode material for sodium-ion batteries owing to its cost-effectiveness and high carbon yield.However,conventional carbonization induces excessive graphitization,yielding insufficient interlayer spacing(d_(002)<0.37 nm)and underdeveloped closed pores.Herein,we propose a dynamic crystallization control strategy through carbothermal shock treatment(1300°C,30 s)that decouples thermodynamic and kinetic constraints.This method precisely modulates graphite domain ordering kinetics,producing short-range ordered structures with expanded interlayer spacing(d_(002)=0.385 nm)and homogeneously distributed closed nanopores.Through combined in situ characterization and first-principles calculations,we elucidate a three-stage crystallization mechanism:(i)amorphous carbon transformation,(ii)open-pore collapse,and(iii)pseudo-graphitic ordering.The optimized HC achieves record performance with 88.6%initial Coulombic efficiency and 204 mA h g^(−1)plateau capacity,while its optimal interlayer spacing lowers Na+diffusion barriers to enable exceptional rate capability(221 mA h g^(−1)at 0.5C after 300 cycles).Practical pouch cells maintain 85%capacity retention after 100 cycles at−20°C and deliver 284 Wh kg^(−1)energy density.This work establishes a kinetic regulation paradigm for graphitization-prone precursors,advancing the rational design of high-performance HC anodes. 展开更多
关键词 Carbothermal shock ANTHRACITE Hard carbon Sodium-ion batteries Initial Coulombic efficiency
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Energy Efficient Covert Communication in a Direct Uplink Satellite-Ground Communication Scenario
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作者 Fu Shu Zeng Wen +1 位作者 Yin Liuguo Zhao Lian 《China Communications》 2026年第1期166-174,共9页
Efficient energy utilization in covert communication sustains covertness while assuring communication quality and efficiency.This paper investigates covert communication energy efficiency(EE)in direct uplink satellite... Efficient energy utilization in covert communication sustains covertness while assuring communication quality and efficiency.This paper investigates covert communication energy efficiency(EE)in direct uplink satellite-ground communications,focusing on enhancing system EE via optimized transmit beamforming and satellite orbit altitude selection.This paper first establishes an optimization problem to maximize system EE in a direct uplink satelliteground covert communication scenario.To solve this non-convex optimization problem,it is decomposed into two subproblems and solved using the successive convex approximation(SCA)method.Based on the above methods,this paper proposes an overall iterative optimization algorithm.Simulation results demonstrate that the proposed algorithm surpasses the conventional baseline algorithms in terms of system EE.Furthermore,they elucidate the correlation between the amount of information received by the receiver and the variations in the satellite’s orbital altitude. 展开更多
关键词 covert communication direct uplink satellite-ground communication energy efficiency
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Unlocking Edge Fine-Tuning:A Sample-Efficient Language-Empowered Split Fine-Tuning Framework
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作者 Zuyi Huang Yue Wang +4 位作者 Jia Liu Haodong Yi Lejun Ai Min Chen Salman A.AlQahtani 《Computers, Materials & Continua》 2026年第4期1584-1606,共23页
The personalized fine-tuning of large languagemodels(LLMs)on edge devices is severely constrained by limited computation resources.Although split federated learning alleviates on-device burdens,its effectiveness dimin... The personalized fine-tuning of large languagemodels(LLMs)on edge devices is severely constrained by limited computation resources.Although split federated learning alleviates on-device burdens,its effectiveness diminishes in few-shot reasoning scenarios due to the low data efficiency of conventional supervised fine-tuning,which leads to excessive communication overhead.To address this,we propose Language-Empowered Split Fine-Tuning(LESFT),a framework that integrates split architectures with a contrastive-inspired fine-tuning paradigm.LESFT simultaneously learns frommultiple logically equivalent but linguistically diverse reasoning chains,providing richer supervisory signals and improving data efficiency.This process-oriented training allows more effective reasoning adaptation with fewer samples.Extensive experiments demonstrate that LESFT consistently outperforms strong baselines such as SplitLoRA in task accuracy.LESFT consistently outperforms strong baselines on GSM8K,CommonsenseQA,and AQUA_RAT,with the largest gains observed on Qwen2.5-3B.These results indicate that LESFT can effectively adapt large language models for reasoning tasks under the computational and communication constraints of edge environments. 展开更多
关键词 Large language models edge computing efficient fine-tuning few-shot fine-tuning split federated learning
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Efficient Arabic Essay Scoring with Hybrid Models: Feature Selection, Data Optimization, and Performance Trade-Offs
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作者 Mohamed Ezz Meshrif Alruily +4 位作者 Ayman Mohamed Mostafa Alaa SAlaerjan Bader Aldughayfiq Hisham Allahem Abdulaziz Shehab 《Computers, Materials & Continua》 2026年第1期2274-2301,共28页
Automated essay scoring(AES)systems have gained significant importance in educational settings,offering a scalable,efficient,and objective method for evaluating student essays.However,developing AES systems for Arabic... Automated essay scoring(AES)systems have gained significant importance in educational settings,offering a scalable,efficient,and objective method for evaluating student essays.However,developing AES systems for Arabic poses distinct challenges due to the language’s complex morphology,diglossia,and the scarcity of annotated datasets.This paper presents a hybrid approach to Arabic AES by combining text-based,vector-based,and embeddingbased similarity measures to improve essay scoring accuracy while minimizing the training data required.Using a large Arabic essay dataset categorized into thematic groups,the study conducted four experiments to evaluate the impact of feature selection,data size,and model performance.Experiment 1 established a baseline using a non-machine learning approach,selecting top-N correlated features to predict essay scores.The subsequent experiments employed 5-fold cross-validation.Experiment 2 showed that combining embedding-based,text-based,and vector-based features in a Random Forest(RF)model achieved an R2 of 88.92%and an accuracy of 83.3%within a 0.5-point tolerance.Experiment 3 further refined the feature selection process,demonstrating that 19 correlated features yielded optimal results,improving R2 to 88.95%.In Experiment 4,an optimal data efficiency training approach was introduced,where training data portions increased from 5%to 50%.The study found that using just 10%of the data achieved near-peak performance,with an R2 of 85.49%,emphasizing an effective trade-off between performance and computational costs.These findings highlight the potential of the hybrid approach for developing scalable Arabic AES systems,especially in low-resource environments,addressing linguistic challenges while ensuring efficient data usage. 展开更多
关键词 Automated essay scoring text-based features vector-based features embedding-based features feature selection optimal data efficiency
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Establishing an induced infertile chicken line for efficient germline transmission of exogenous PGCs
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作者 Haimei Qin Xiaoxuan Jia +7 位作者 Zhenwen Huang Yifei Zhi Na Ji Meiyu Lan Lang Zhang Xingting Liu Huiyan Xu Yangqing Lu 《Journal of Integrative Agriculture》 2026年第1期227-234,共8页
Primordial germ cells(PGCs)are the stem-cell population of adult animal gametes,which develop into sperm or eggs.It can be propagated in vitro and injected into the host chicken for genome editing to obtain germline c... Primordial germ cells(PGCs)are the stem-cell population of adult animal gametes,which develop into sperm or eggs.It can be propagated in vitro and injected into the host chicken for genome editing to obtain germline chimeric chicken.However,it has the limitation that the host embryo contains endogenous PGCs,which raises complications,resultantly donor PGCs fail to compete,and transmission efficiency reduced.Therefore,to increase the transmission efficiency,we generated a novel sterile chicken with the inducible elimination of endogenous PGCs in the host.This is the first study that applied the herpes simplex virus thymidine kinase(HSV-TK)cell ablation system in avian.CRISPR/Cas9-mediated homology-directed repair was performed to localize the HSV-TK suicide gene to the last exon of the deleted in azoospermialike(DAZL)gene,and ganciclovir(GCV)was added to induce the apoptosis in the germ cells of the host embryo.The sterilized host embryo introduced genome-edited PGCs to produce chimeric chicken carrying exogenous germ cells only.It was observed that the germline transmission efficiency was 100%achieved,and the obtained chicks were purely from donor breeds.The technologies established in the current study have important applications in germplasm conservation and gene editing in chicken. 展开更多
关键词 chicken embryos germline transmission efficiency herpes simplex virus thymidine kinase primordial germ cells
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Granulated straw incorporation efficiently promotes soil organic carbon pool in subtropical infertile croplands primarily via plant residues accumulation
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作者 Jun Wang Xun Duan +9 位作者 Yijun Xu Kaiwen Deng Wei Gao Miaomiao Zhang Yajun Hu Shoulong Liu Zhenhua Zhang Wenju Zhang Jinshui Wu Xiangbi Chen 《Journal of Integrative Agriculture》 2026年第2期501-512,共12页
Rapidly improving infertile croplands and enhancing their soil organic carbon(SOC)pool necessitate substantial organic materials incorporation.Converting loose crop straw into granulated form facilitates uniform incor... Rapidly improving infertile croplands and enhancing their soil organic carbon(SOC)pool necessitate substantial organic materials incorporation.Converting loose crop straw into granulated form facilitates uniform incorporation within the plough soil layer.As an innovative soil amelioration approach,the efficiency and patterns of SOC accumulation remain unclear.Two field experiments were conducted in infertile subtropical upland and paddy soils with 0,30,60,and 90 Mg ha^(-1)granulated straw incorporation.After one year,SOC accumulation efficiency from straw input remained stable in upland(30.8–37.5%)with increasing amounts of straw incorporation,while declined from 60.0 to 38.3%in paddy.In both croplands,the contributions of lignin phenols to SOC increased with increasing straw incorporation,while the contributions from amino sugars remained constant at higher straw input levels.Subsequently,the ratios of lignin phenols to amino sugars increased with increasing straw incorporation,indicating faster plant residue accumulation compared to microbial necromass,as the granulation approach limited microbial involvement in straw transformation.Thus,single-time incorporation of substantial granulated straw presents an effective agricultural strategy for rapid amelioration of infertile croplands. 展开更多
关键词 SOC accumulation efficiency granulated straw upland and paddy plant residues microbial necromass microbial community
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A peridynamics modeling approach for pre-cracked rock cracking processes under impact by integrating Drucker-Prager plasticity model and efficient contact model
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作者 Jingzhi Tu Nengxiong Xu Gang Mei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期179-195,共17页
In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical propert... In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical properties of rocks,the cracking processes of pre-cracked rocks have been extensively studied using numerical modeling methods.The peridynamics(PD)exhibits advantages over other numerical methods due to the absence of the requirements for remeshing and external crack growth criterion.However,for modeling pre-cracked rock cracking processes under impact,current PD implementations lack generally applicable rock constitutive models and impact contact models,which leads to difficulties in determining rock material parameters and efficiently calculating impact loads.This paper proposes a non-ordinary state-based peridynamics(NOSBPD)modeling method integrating the Drucker-Prager(DP)plasticity model and an efficient contact model to address the above problems.In the proposed method,the Drucker-Prager plasticity model is integrated into the NOSBPD,thereby equipping NOSBPD with the capability to accurately characterize the nonlinear stress-strain relationship inherent in rocks.An efficient contact model between particles and meshes is designed to calculate the impact loads,which is essentially a coupling method of PD with the finite element method(FEM).The effectiveness of the proposed NOSBPD modeling method is verified by comparison with other numerical methods and experiments.Experimental results indicate that the proposed method can effectively and accurately predict the 3D cracking processes of pre-cracked cracks under impact loading,and the maximum principal stress is the key driver behind wing crack formation in pre-cracked rocks. 展开更多
关键词 Pre-cracked rocks Cracking processes Non-ordinary state-based peridynamics (NOSBPD) Drucker-Prager plasticity model efficient contact model
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FedCCM:Communication-Efficient Federated Learning via Clustered Client Momentum in Non-IID Settings
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作者 Hang Wen Kai Zeng 《Computers, Materials & Continua》 2026年第3期1690-1707,共18页
Federated learning often experiences slow and unstable convergence due to edge-side data heterogeneity.This problem becomes more severe when edge participation rate is low,as the information collected from different e... Federated learning often experiences slow and unstable convergence due to edge-side data heterogeneity.This problem becomes more severe when edge participation rate is low,as the information collected from different edge devices varies significantly.As a result,communication overhead increases,which further slows down the convergence process.To address this challenge,we propose a simple yet effective federated learning framework that improves consistency among edge devices.The core idea is clusters the lookahead gradients collected from edge devices on the cloud server to obtain personalized momentum for steering local updates.In parallel,a global momentum is applied during model aggregation,enabling faster convergence while preserving personalization.This strategy enables efficient propagation of the estimated global update direction to all participating edge devices and maintains alignment in local training,without introducing extra memory or communication overhead.We conduct extensive experiments on benchmark datasets such as Cifar100 and Tiny-ImageNet.The results confirm the effectiveness of our framework.On CIFAR-100,our method reaches 55%accuracy with 37 fewer rounds and achieves a competitive final accuracy of 65.46%.Even under extreme non-IID scenarios,it delivers significant improvements in both accuracy and communication efficiency.The implementation is publicly available at https://github.com/sjmp525/CollaborativeComputing/tree/FedCCM(accessed on 20 October 2025). 展开更多
关键词 Federated learning distributed computation communication efficient momentum clustering non-independent and identically distributed(non-IID)
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基于双流特征交叉融合Efficient Transformer的人脸表情识别
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作者 党宏社 孟饶辰 高宛蓉 《计算机工程与应用》 北大核心 2025年第15期251-257,共7页
面部表情识别在人机交互等现实应用中得到了越来越多的重视。为解决传统方法中由于类间相似性和类内差异引起的识别准确率低等问题,提出了一种双流特征交叉融合Efficient Transformer识别人脸表情的方法。使用IResNet50和MobileFaceNet... 面部表情识别在人机交互等现实应用中得到了越来越多的重视。为解决传统方法中由于类间相似性和类内差异引起的识别准确率低等问题,提出了一种双流特征交叉融合Efficient Transformer识别人脸表情的方法。使用IResNet50和MobileFaceNet分别提取人脸表情的图像和关键点的多尺度特征,同时采用通道注意力机制来增强关键特征并减少参数量;引入了交叉融合高效多头自注意力机制(cross fusion efficient multi-head self-attention,CFEMSA),对相同尺度的双流特征进行交叉融合,以突出面部显著特征;最后采用特征金字塔结构对不同尺度的交叉融合结果进行多尺度融合,以提高识别的准确性。提出的方法在RAF-DB、AffecNet-7和AffecNet-8数据集上的识别准确率分别为91.82%、67.46%和63.65%,实验结果证明该方法有效缓解了类间相似性和类内差异所引起的识别准确率低的问题。 展开更多
关键词 面部表情识别 efficient Transformer 交叉融合 多尺度特征 特征融合
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基于CNN和Efficient Transformer的多尺度遥感图像语义分割算法 被引量:3
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作者 张振利 胡新凯 +2 位作者 李凡 冯志成 陈智超 《浙江大学学报(工学版)》 北大核心 2025年第4期778-786,共9页
针对现有方法存在遥感图像的多尺度地物特征提取困难和目标边缘分割不准确的问题,提出新的语义分割算法.利用CNN和Efficient Transformer构建双编码器,解耦上下文信息和空间信息.提出特征融合模块加强编码器间的信息交互,有效融合全局... 针对现有方法存在遥感图像的多尺度地物特征提取困难和目标边缘分割不准确的问题,提出新的语义分割算法.利用CNN和Efficient Transformer构建双编码器,解耦上下文信息和空间信息.提出特征融合模块加强编码器间的信息交互,有效融合全局上下文信息和局部细节信息.构建分层Transformer结构提取不同尺度的特征信息,使编码器有效专注不同尺度的物体.提出边缘细化损失函数,缓解遥感图像目标边缘分割不准确的问题.实验结果表明,在ISPRS Vaihingen和ISPRS Potsdam数据集上,所提算法的平均交并比(MIoU)分别为72.45%和82.29%.在SAMRS数据集中的SOTA、SIOR和FAST子集上,所提算法的MIoU分别为88.81%、97.29%和86.65%,总体精度和平均交并比指标均优于对比模型.所提算法在各类不同尺度的目标上有较好的分割性能. 展开更多
关键词 遥感图像 语义分割 双编码器结构 特征融合 efficient Transformer
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SEFormer:A Lightweight CNN-Transformer Based on Separable Multiscale Depthwise Convolution and Efficient Self-Attention for Rotating Machinery Fault Diagnosis 被引量:3
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作者 Hongxing Wang Xilai Ju +1 位作者 Hua Zhu Huafeng Li 《Computers, Materials & Continua》 SCIE EI 2025年第1期1417-1437,共21页
Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain limitations.Conversely,deep learning techniques have gained promine... Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain limitations.Conversely,deep learning techniques have gained prominence as a central focus of research in the field of fault diagnosis by strong fault feature extraction ability and end-to-end fault diagnosis efficiency.Recently,utilizing the respective advantages of convolution neural network(CNN)and Transformer in local and global feature extraction,research on cooperating the two have demonstrated promise in the field of fault diagnosis.However,the cross-channel convolution mechanism in CNN and the self-attention calculations in Transformer contribute to excessive complexity in the cooperative model.This complexity results in high computational costs and limited industrial applicability.To tackle the above challenges,this paper proposes a lightweight CNN-Transformer named as SEFormer for rotating machinery fault diagnosis.First,a separable multiscale depthwise convolution block is designed to extract and integrate multiscale feature information from different channel dimensions of vibration signals.Then,an efficient self-attention block is developed to capture critical fine-grained features of the signal from a global perspective.Finally,experimental results on the planetary gearbox dataset and themotor roller bearing dataset prove that the proposed framework can balance the advantages of robustness,generalization and lightweight compared to recent state-of-the-art fault diagnosis models based on CNN and Transformer.This study presents a feasible strategy for developing a lightweight rotating machinery fault diagnosis framework aimed at economical deployment. 展开更多
关键词 CNN-Transformer separable multiscale depthwise convolution efficient self-attention fault diagnosis
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Safe flight corridor constrained sequential convex programming for efficient trajectory generation of fixed-wing UAVs 被引量:2
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作者 Jing SUN Guangtong XU +2 位作者 Zhu WANG Teng LONG Jingliang SUN 《Chinese Journal of Aeronautics》 2025年第1期537-550,共14页
Generating dynamically feasible trajectory for fixed-wing Unmanned Aerial Vehicles(UAVs)in dense obstacle environments remains computationally intractable.This paper proposes a Safe Flight Corridor constrained Sequent... Generating dynamically feasible trajectory for fixed-wing Unmanned Aerial Vehicles(UAVs)in dense obstacle environments remains computationally intractable.This paper proposes a Safe Flight Corridor constrained Sequential Convex Programming(SFC-SCP)to improve the computation efficiency and reliability of trajectory generation.SFC-SCP combines the front-end convex polyhedron SFC construction and back-end SCP-based trajectory optimization.A Sparse A^(*)Search(SAS)driven SFC construction method is designed to efficiently generate polyhedron SFC according to the geometric relation among obstacles and collision-free waypoints.Via transforming the nonconvex obstacle-avoidance constraints to linear inequality constraints,SFC can mitigate infeasibility of trajectory planning and reduce computation complexity.Then,SCP casts the nonlinear trajectory optimization subject to SFC into convex programming subproblems to decrease the problem complexity.In addition,a convex optimizer based on interior point method is customized,where the search direction is calculated via successive elimination to further improve efficiency.Simulation experiments on dense obstacle scenarios show that SFC-SCP can generate dynamically feasible safe trajectory rapidly.Comparative studies with state-of-the-art SCP-based methods demonstrate the efficiency and reliability merits of SFC-SCP.Besides,the customized convex optimizer outperforms off-the-shelf optimizers in terms of computation time. 展开更多
关键词 Fixed-wing unmanned aerial vehicle efficient trajectory planning Safe flight corridor Sequential convex programming Customized convex optimizer
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A New Encryption Mechanism Supporting the Update of Encrypted Data for Secure and Efficient Collaboration in the Cloud Environment
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作者 Chanhyeong Cho Byeori Kim +1 位作者 Haehyun Cho Taek-Young Youn 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期813-834,共22页
With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly increased.However,traditional collaboration tools primarily rely on access control,leaving data stored on cloud... With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly increased.However,traditional collaboration tools primarily rely on access control,leaving data stored on cloud servers vulnerable due to insufficient encryption.This paper introduces a novel mechanism that encrypts data in‘bundle’units,designed to meet the dual requirements of efficiency and security for frequently updated collaborative data.Each bundle includes updated information,allowing only the updated portions to be reencrypted when changes occur.The encryption method proposed in this paper addresses the inefficiencies of traditional encryption modes,such as Cipher Block Chaining(CBC)and Counter(CTR),which require decrypting and re-encrypting the entire dataset whenever updates occur.The proposed method leverages update-specific information embedded within data bundles and metadata that maps the relationship between these bundles and the plaintext data.By utilizing this information,the method accurately identifies the modified portions and applies algorithms to selectively re-encrypt only those sections.This approach significantly enhances the efficiency of data updates while maintaining high performance,particularly in large-scale data environments.To validate this approach,we conducted experiments measuring execution time as both the size of the modified data and the total dataset size varied.Results show that the proposed method significantly outperforms CBC and CTR modes in execution speed,with greater performance gains as data size increases.Additionally,our security evaluation confirms that this method provides robust protection against both passive and active attacks. 展开更多
关键词 Cloud collaboration mode of operation data update efficiency
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Identification of Pi-efficient elite allele of the TaPHT1;6 gene and development of its functional marker in common wheat(Triticum aestivum L.) 被引量:1
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作者 Huanting Shi Chuang Lou +7 位作者 Jinfeng Wang Dianqi Dong Longfei Yang Gezi Li Zhiqiang Tian Qiaoxia Han Pengfei Wang Guozhang Kang 《Journal of Integrative Agriculture》 2025年第5期1646-1655,共10页
One of agriculture’s major challenges is the low efficiency of phosphate(Pi)use,which leads to increased costs,harmful environmental impacts,and the depletion of phosphorus(P)resources.The TaPHT1;6 gene,which encodes... One of agriculture’s major challenges is the low efficiency of phosphate(Pi)use,which leads to increased costs,harmful environmental impacts,and the depletion of phosphorus(P)resources.The TaPHT1;6 gene,which encodes a high-affinity Pi transporter(PHT),plays a crucial role in Pi absorption and transport.In this study,the promoter and coding regions of three TaPHT1;6 gene copies on chromosomes 5A,5B,and 5D were individually amplified and sequenced from 167 common wheat(Triticum aestivum L.)cultivars.Sequence analysis revealed 16 allelic variation sites within the promoters of TaPHT1;6-5B among these cultivars,forming three distinct haplotypes:Hap1,Hap2,and Hap3.Field trials were conducted over two years to compare wheat genotypes with these haplotypes,focusing on assessing plant dry weight,grain yield,P content,Pi fertilizer absorption efficiency,and Pi fertilizer utilization efficiency.Results indicated that Hap3 represented the favored Pi-efficient haplotype.Dual-luciferase reporter assay demonstrated that the Hap3 promoter,carrying the identified allelic variation sites,exhibited higher gene-driven capability,leading to increased expression levels of the TaPHT1;6-5B gene.We developed a distributed cleaved amplified polymorphic site marker(dCAPS-571)to distinguish Hap3 from the other two haplotypes based on these allelic variation sites,presenting an opportunity for breeding Pi-efficient wheat cultivars.This study successfully identified polymorphic sites on TaPHT1;6-5B associated with Pi efficiency and developed a functional molecular marker to facilitate future breeding endeavors. 展开更多
关键词 Triticum aestivum L. high-affinity Pi transporter Pi use efficiency Pi-efficient molecular marker
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基于EfficientNetV2的PCB缺陷检测算法 被引量:3
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作者 尹嘉超 吕耀文 +1 位作者 索科 黄玺 《计算机辅助设计与图形学学报》 北大核心 2025年第7期1260-1269,共10页
印刷电路板(PCB)是一种高精密的电子元器件,其优良与否对电子产品的质量有着重要影响.但现有的PCB缺陷检测算法存在着检测精度不高,特别是缺陷定位不够精确等问题.针对以上问题,提出一种基于EfficientNetV2的PCB缺陷检测算法.在Faster R... 印刷电路板(PCB)是一种高精密的电子元器件,其优良与否对电子产品的质量有着重要影响.但现有的PCB缺陷检测算法存在着检测精度不高,特别是缺陷定位不够精确等问题.针对以上问题,提出一种基于EfficientNetV2的PCB缺陷检测算法.在Faster R-CNN的基础上,通过选用特征提取能力更强的EfficientNetV2_M作为特征提取网络,同时使用通道注意力机制(ECA)对特征融合网络FPN进行优化,提高了细节信息提取能力.在北京大学智能机器人开放实验室发布的PCB瑕疵数据集上的实验结果表明,相较于目前检测效果最好的PCB缺陷检测算法LWN-Net,改进后的缺陷检测算法在IoU=0.50时mAP由99.58%提升到99.66%;在IoU=[0.50:0.95]时mAP由52.6%提升到79.4%.该网络在提升了PCB的检测精度的同时,解决了缺陷定位不够精确的问题,实现了高精度的PCB缺陷检测,具有一定的实际意义.代码已经开源在https://github.com/ChaO989/Defect_detection. 展开更多
关键词 印刷电路板 efficientNetV2 缺陷检测 Faster R-CNN 高效通道注意力
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Multi-Band Integrated Networking for Efficient Spectrum Utilization in 6G 被引量:1
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作者 Wang Ailing Kong Lei +4 位作者 Liu Jianjun Xia Liang Wang Xiaoqian Wang Qixing Liu Guangyi 《China Communications》 2025年第4期42-54,共13页
The sixth-generation(6G)networks will consist of multiple bands such as low-frequency,midfrequency,millimeter wave,terahertz and other bands to meet various business requirements and networking scenarios.The dynamic c... The sixth-generation(6G)networks will consist of multiple bands such as low-frequency,midfrequency,millimeter wave,terahertz and other bands to meet various business requirements and networking scenarios.The dynamic complementarity of multiple bands are crucial for enhancing the spectrum efficiency,reducing network energy consumption,and ensuring a consistent user experience.This paper investigates the present researches and challenges associated with deployment of multi-band integrated networks in existing infrastructures.Then,an evolutionary path for integrated networking is proposed with the consideration of maturity of emerging technologies and practical network deployment.The proposed design principles for 6G multi-band integrated networking aim to achieve on-demand networking objectives,while the architecture supports full spectrum access and collaboration between high and low frequencies.In addition,the potential key air interface technologies and intelligent technologies for integrated networking are comprehensively discussed.It will be a crucial basis for the subsequent standards promotion of 6G multi-band integrated networking technology. 展开更多
关键词 full spectrum access high and low frequency collaboration multi-band integrated networking 6G spectrum efficiency
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An Efficient and Accurate Solution for the PnPL Problem 被引量:1
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作者 Ridma Basnayaka Qida Yu 《Instrumentation》 2025年第3期63-75,共13页
Camera Pose Estimating from point and line correspondences is critical in various applications,including robotics,augmented reality,3D reconstruction,and autonomous navigation.Existing methods,such as the Perspective-... Camera Pose Estimating from point and line correspondences is critical in various applications,including robotics,augmented reality,3D reconstruction,and autonomous navigation.Existing methods,such as the Perspective-n-Point(PnP)and Perspective-n-Line(PnL)approaches,offer limited accuracy and robustness in environments with occlusions,noise,or sparse feature data.This paper presents a unified solution,Efficient and Accurate Pose Estimation from Point and Line Correspondences(EAPnPL),combining point-based and linebased constraints to improve pose estimation accuracy and computational efficiency,particularly in low-altitude UAV navigation and obstacle avoidance.The proposed method utilizes quaternion parameterization of the rotation matrix to overcome singularity issues and address challenges in traditional rotation matrix-based formulations.A hybrid optimization framework is developed to integrate both point and line constraints,providing a more robust and stable solution in complex scenarios.The method is evaluated using synthetic and realworld datasets,demonstrating significant improvements in performance over existing techniques.The results indicate that the EAPnPL method enhances accuracy and reduces computational complexity,making it suitable for real-time applications in autonomous UAV systems.This approach offers a promising solution to the limitations of existing camera pose estimation methods,with potential applications in low-altitude navigation,autonomous robotics,and 3D scene reconstruction. 展开更多
关键词 camera pose estimation efficient and accurate pose estimation(eapnpl) UAV navigation obstacle avoidance point-and-line correspondences
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Enhancing energy security through efficient decarbonization:Impact of China’s“Constructing Large Units and Restricting Small Ones”policy on thermal power productivity
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作者 Jinsong Zhao Chin-Hsien Yu Xinghao Li 《Chinese Journal of Population,Resources and Environment》 2025年第2期168-180,共13页
Developing low-carbon and efficient power systems is critical for energy security in the global warming context.We address this issue by focusing on the productivity impact of a decarbonization policy in China’s ther... Developing low-carbon and efficient power systems is critical for energy security in the global warming context.We address this issue by focusing on the productivity impact of a decarbonization policy in China’s thermal power sector—namely,the“Constructing Large Units and Restricting Small Ones”(CLRS)initiative.Utilizing a resource misallocation model,we construct a new theoretical framework to distinguish between technical and allocative efficiency and analyze productivity using plant-level data.The results indicate that the CLRS policy has significantly improved the allocative and technical efficiency of China’s coal-fired power sector,thereby ensuring power security.The closure of outdated and highly distorted small coal-fired units,which have been replaced by technologically advanced large units,primarily drives the enhanced efficiency.The policy’s effects are most pronounced in large-scale power plants and those with high coal combustion efficiency.Furthermore,a comparison of power plants’productivity distribution before and after policy implementation reveals that the CLRS policy not only enhances capital productivity in the coal-fired power sector but also increases rational labor allocation.Our findings have important policy implications for developing countries vis-à-vis building efficient and stable power systems amid climate change. 展开更多
关键词 Decarbonization policy Energy security Thermal power Technical efficiency Resource allocative efficiency
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Efficient Production of Pyrrolnitrin by Optimizing Culture Medium and Blocking Competitive Secondary Metabolic Pathways in Pseudomonas protegens JP2-4390
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作者 SHEN Jiamin ZHANG Xinxin +2 位作者 WANG Yucong CHEN Guoqing FENG Guozhong 《Rice science》 2025年第2期156-159,I0033-I0040,共12页
Pyrrolnitrin(PRN),a natural halogenated phenylpyrrole derivative,exhibits a broad spectrum of antimicrobial activity against a wide range of bacteria and fungi.In this study,we isolated a strain of Pseudomonas protege... Pyrrolnitrin(PRN),a natural halogenated phenylpyrrole derivative,exhibits a broad spectrum of antimicrobial activity against a wide range of bacteria and fungi.In this study,we isolated a strain of Pseudomonas protegens JP2-4390 from the rhizosphere soil of rice plants,which showed strong inhibitory activity against Rhizoctonia solani. 展开更多
关键词 DERIVATIVE spectrum efficient
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