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Prone position ventilation in severe acute pancreatitis patients with concurrent acute respiratory distress syndrome and abdominal compartment syndrome:a case report 认领 引用
1
作者 Jiaping Yu Yun Ji Haifei Lu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2026年第1期98-100,共3页
Severe acute pancreatitis(SAP)can induce acute respiratory distress syndrome(ARDS)and abdominal compartment syndrome(ACS).Although prone position ventilation(PPV)can improve outcomes in patients with ARDS,there is sig... Severe acute pancreatitis(SAP)can induce acute respiratory distress syndrome(ARDS)and abdominal compartment syndrome(ACS).Although prone position ventilation(PPV)can improve outcomes in patients with ARDS,there is significant controversy regarding its concurrent use with ACS owing to concerns of increased risk of intra-abdominal pressure(IAP).[1]We present a case of successful PPV application without adverse eff ects. 展开更多
关键词 severe acute pancreatitis sap can prone position ventilation ppv can acute respiratory distress syndrome abdominal compartment syndrome abdominal compartment syndrome acs prone position ventilation intra abdominal pressure acute respiratory distress syndrome ards
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Beyond Classical Positional Encodings:A Learnable QFT-Inspired Framework for Transformer Language Models 认领 引用
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作者 Sara Tehsin Tallha Akram +2 位作者 Syed Rameez Naqvi Meshal Alharbi Abdulrahman Alabduljabbar 《Computers, Materials & Continua》 SCIE EI 2026年第9期159-182,共24页
Transformers have become the dominant architecture for sequence modeling in natural language processing;however,their effectiveness critically depends on how positional information is encoded.Conventional positional e... Transformers have become the dominant architecture for sequence modeling in natural language processing;however,their effectiveness critically depends on how positional information is encoded.Conventional positional encodings,while effective,may have limited structural flexibility for capturing complex global sequence relationships.Recent quantum-inspired approaches have sought to address this limitation,yetmany either oversimplify quantum principles or introduce substantial computational or hardware overhead.We introduce a novel Quantum Fourier Transform(QFT)-inspired positional encoding scheme for transformers,motivated by the structured frequency representation of the QFT.Unlike prior approaches that either emulate quantum operations superficially or require complex circuit constructions,the proposed method provides a learnable hybrid encoding that preserves quantuminspired structure while remaining aligned with hardware-efficient circuit primitives and structurally compatible with future near-term quantum implementations.Experiments on WikiText-103 indicate that the proposed encoding achieves competitive perplexity,improved robustness to input scrambling,and stable training behavior relative to alternative quantum-inspired baselines under the evaluated settings.Preliminary circuit-level simulations further suggest favorable noise resilience of the associated encoding primitives.These findings support the potential utility of incorporating quantum-inspired design principles into deep learning architectures and provide a foundation for future exploration at the interface of quantum computing and transformer-based natural language processing(NLP). 展开更多
关键词 LLMs positional encoding Quantum Fourier Transform positional embeddings hybrid quantumclassical models near-term quantum devices quantum transformer
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Reverse Nystagmus During Canalith Repositioning:A Misunderstood Predictor of Failed Epley Maneuver:A Retrospective Study Based on 60 Patients with Posterior Semicircular Canal BPPV 认领 引用
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作者 Jing Chen Shuo Yang 《Journal of Otology》 CSCD 2026年第3期172-176,共5页
Objective:To analyze the types,directions,and intensities of nystagmus occurring during each step(positions 2,3,and 4)of the Epley maneuver in patients with posterior semicircular canal benign paroxysmal positional ve... Objective:To analyze the types,directions,and intensities of nystagmus occurring during each step(positions 2,3,and 4)of the Epley maneuver in patients with posterior semicircular canal benign paroxysmal positional vertigo(BPPV),and to explore their relationship with a positive Dix-Hallpike test at 24-48 hours post-maneuver,indicating incomplete canalith clearance.Methods:Clinical data from 60 patients with unilateral posterior semicircular canal canalithiasis were retrospectively analyzed.All patients underwent a standard Epley maneuver under video nystagmography(VNG)monitoring.The direction and slow phase velocity(SPV)of nystagmus were recorded at each repositioning step.The need for a second repo-sitioning was determined by repeat Dix-Hallpike test 24-48 hours after the maneuver.Univariate and multivariate logistic regression analyses were performed to identify associations between nystagmus characteristics at each step and the need for a second procedure.Sensitivity,specificity,and predictive values were calculated.Results:Among 60 patients,19(31.7%)required a second repositioning.Univariate analysis showed that reverse nystagmus at position 3,reverse nystagmus at position 4,reverse nystagmus at either position 3 or 4,SPV of reverse nystagmus at position 4≥10°/s,diagnostic vertical SPV≥20°/s,and latency≤2 s were significantly associated with the need for a second procedure(all P0.05).All four patients who exhibited down-beating nystagmus did not require a second procedure.Conclusion:During the Epley maneuver,reverse nystagmus occurring at position 4 is the strongest predictor of the need for a second repositioning,with a positive predictive value exceeding 94%.Down-beating nystagmus indicates a favorable outcome and was associated with a lower probability of requiring a second repositioning.Real-time nystagmus feedback during the procedure allows early identification of high-risk patients and enables optimized,individualized follow-up strategies. 展开更多
关键词 Benign Paroxysmal Positional Vertigo Epley Maneuver Reverse Nystagmus Second Repositioning Nystagmus Prognostic Prediction
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Enhancing monocular visual positioning:3D target-assisted initialization 认领 引用
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作者 MA Junyu SUN Changku +1 位作者 WANG Peng FU Luhua 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2026年第1期36-48,共13页
Monocular visual positioning systems are valued for their low cost and straightforward calibration.However,the lack of real-scale information and the complexity of initialization processes limit their application in s... Monocular visual positioning systems are valued for their low cost and straightforward calibration.However,the lack of real-scale information and the complexity of initialization processes limit their application in scenarios requiring accurate absolute positioning.Existing solutions present trade-offs:markerless approaches depend on environmental priors(e.g.,fixed camera height constraints)for scale recovery,while marker-based methods typically necessitate that target patterns remain within the camera’s field of view throughout the process.To address these challenges,we propose a 3D target-assisted initialization method that enables scale recovery with just two target images.This modular approach can be seamlessly integrated into monocular simultaneous localization and mapping(SLAM)frameworks.We validated our proposed initialization method through integration with ORB-SLAM3 and semi-direct visual odometry(SVO).Experimental results demonstrated that our method provides real-scale information without compromising real-time performance,making it suitable for applications such as indoor navigation and industrial robot localization,where accurate absolute positioning is essential. 展开更多
关键词 monocular simultaneous localization and mapping(SLAM) real-time positioning scale recovery 3D target absolute positioning visual odometry
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Precise regulation of acid centers in different cavities of FER-zeolite via selective passivation to identify pentene monomolecular cracking reaction position 认领 引用
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作者 Fang Li Penghe Zhang +2 位作者 Yiran Wang Yueming Liu Mingyuan He 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2026年第2期136-147,共12页
Precisely controlling acid center position in zeolites is still challenging.Pentene monomolecular cracking offers an ideal route to maximize ethylene and propylene yields simultaneously.To reveal the relationship betw... Precisely controlling acid center position in zeolites is still challenging.Pentene monomolecular cracking offers an ideal route to maximize ethylene and propylene yields simultaneously.To reveal the relationship between acid site distribution in FER-zeolite and pentene monomolecular cracking activity,this study proposes a novel strategy integrating pyridine pre-adsorption with K+ exchange modification to selectively shield acid sites within FER cages,while phosphorus modification is employed to selectively passivate acid sites in 10-MR channels and on the external surface.Adsorption infrared(IR)spectroscopy(CD3CN-IR,Py-IR,and 2,6-DMPy-IR),and OH-IR characterization verified the selectivity and efficiency of these modification process.FER zeolites with distinct acid site distributions exhibit typical monomolecular cracking characteristics in pentene cracking,where the pentene cracking activity is linearly related to the acid density in the 10-MR channel and independent of the FER cage acidity.This result identifies 10-MR channel as primary pentene monomolecular cracking reaction position for the first time,providing a theoretical basis for designing zeolite catalysts that maximize ethylene and propylene production.The synergistic application of the pre-adsorption-K+exchange modiϐication strategy using different size basic molecules and phosphorus modification will provide an effective approach for precise control of acid site locations in zeolites with diverse pore/cavities architectures. 展开更多
关键词 FER zeolite Acid centers Selective passivation Pentene monomolecular cracking Catalytic reaction position
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Workspace-based hybrid force position posture alignment for high quality aircraft assembly of large-scale components 认领 引用
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作者 Yajun LI Wei LIU +4 位作者 Hu LU Runze LIU Changyong GAO Qihang CHEN Yang ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第1期553-569,共17页
The high-quality assembly of Large Aircraft Components(LACs)is essential in modern aviation manufacturing.Numerical control locators are employed for the posture adjustment of LAC,yet the system's multi-input mult... The high-quality assembly of Large Aircraft Components(LACs)is essential in modern aviation manufacturing.Numerical control locators are employed for the posture adjustment of LAC,yet the system's multi-input multi-output,nonlinearity,and strong coupling presents significant challenges.The substantial internal force generated during the adjustment process can potentially damage the LAC and degrade the assembly quality.Hence,a workspace-based hybrid force position control scheme was developed to achieve high quality assembly with high-precision and lower internal force.Firstly,an offline workspace analysis with inherent geometric characteristics to form time-varying posture error constraint.Then,the posture error is integrated into the online position axis control to ensure tracking the ideal posture,while the force control axis compensates for posture deviation by minimizing internal force,thereby achieving high precision and low internal force.Finally,the effectiveness was demonstrated through experiments.The root mean square errors of orientation and position are 104 rad and 0.1 mm,respectively.A reduction in internal force can range from 10.96%to 57.4%compared to the traditional method.Key points'max position error is decreased from 0.32 mm to 0.18 mm,satisfying the 0.5 mm tolerance.Therefore,the proposed method will help promote the development of high-performance manufacturing. 展开更多
关键词 Aircraft manufacture Posture alignment Hybrid constraints Workspace analysis Hybrid force position control Internal force
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Direct position determination based on rotating single-baseline interferometer for multiple time-frequency aliased sources 认领 引用
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作者 Yuan ZHANG Guizhou WU +2 位作者 Fucheng GUO Zihan YAO Min ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第2期389-401,共13页
Rotating Single-Baseline Interferometer(RSBI)systems have attracted considerable attention for Direct Position Determination(DPD)due to their simplicity and high localization accuracy.Nevertheless,the growing complexi... Rotating Single-Baseline Interferometer(RSBI)systems have attracted considerable attention for Direct Position Determination(DPD)due to their simplicity and high localization accuracy.Nevertheless,the growing complexity of electromagnetic environments has led to scenarios with multiple time-frequency aliased sources,rendering conventional DPD methods for RSBI systems ineffective.Previous studies have predominantly concentrated on deploying antenna arrays and applying related signal-processing techniques for localization.Typically,these approaches necessitate that the number of physical antennas exceeds the number of sources.For RSBI systems already in practical operation,this would entail the installation of additional physical antennas,which implies equipment recycling and hardware upgrades.In numerous cases,such modifications are unfeasible.This paper proposes a novel Relative Offset-based Direct Position Determination(RO-DPD)method for RSBI systems that can handle multiple time-frequency aliased sources.The proposed method overcomes the challenge of simultaneous positioning without requiring hardware modifications by leveraging time accumulation and algorithmic enhancements.The implementation of the method involves three key steps.Firstly,the rotation of the interferometer is synthesized into a virtual Uniform Circular Array(UCA).Secondly,a novel estimation variable,termed relative offset,is introduced.The variable serves as an intermediate parameter to establish correlation equations between the positions of multiple time-frequency aliased sources and the intercepted signals.Thirdly,the relative offset model in the UCA is transformed into a virtual Uniform Linear Array(ULA)model,from which the cost function can be derived via the Spatial Smoothing(SS)MUSIC algorithm.Theoretical analysis and simulation results verify the effectiveness of the proposed method.Compared with traditional approaches,the RO-DPD method maintains the low complexity of RSBI systems while demonstrating robust performance in complex electromagnetic environments. 展开更多
关键词 Rotating single-baseline interferometer Direct position determination Uniform circular array Array processing
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Formation Control of Multi-Agent Systems With Position Constraints on a Closed Curve 认领 引用
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作者 Cheng Song Yongqin He +1 位作者 Jianbin Qiu Shengyuan Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2026年第4期1004-1006,共3页
Dear Editor,This letter deals with the formation control problem of a multiagent system that moves along a closed curve and is subject to position constraints.A distributed formation control law is developed under whi... Dear Editor,This letter deals with the formation control problem of a multiagent system that moves along a closed curve and is subject to position constraints.A distributed formation control law is developed under which the position constraint of each agent can always be satisfied.Due to the existence of position constraints,prescribed formations generally cannot be achieved by the agents. 展开更多
关键词 position constraint multi agent systems distributed formation control law closed curve formation control multiagent system
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Postoperative effective lens position and refraction changes with three different types of intraocular lens 认领 引用
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作者 Xi-Xia Ding Lin-Feng Xiang +5 位作者 Wen-Tao Tong Dan-Dan Wang Hong-FangZhang Ping-Jun Chang Fu-Man Yang Yun-E Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2026年第2期260-265,共6页
AIM:To evaluate and compare alterations in the effective lens position(ELP)and refractive outcomes among three distinct intraocular lens(IOL)types.METHODS:Patients with cataracts were enrolled and allocated to 3 group... AIM:To evaluate and compare alterations in the effective lens position(ELP)and refractive outcomes among three distinct intraocular lens(IOL)types.METHODS:Patients with cataracts were enrolled and allocated to 3 groups:Group A(implanted with the SN6CWS),Group B(implanted with the MI60),and Group C(implanted with the Aspira-aA).ELP measurements were obtained with swept-source optical coherence tomography(SS-OCT)at 1d,1wk,1mo,and 3mo postoperatively.Subjective refraction assessments were conducted at 1wk,1mo,and 3mo following surgery.RESULTS:The study included 189 eyes of 150 cataract patients(66 males).There were 77 eyes in Group A,55 eyes in Group B,and 57 eyes in Group C.The root mean square of the ELP(ELPRMS)within the initial 3mo was significantly lower for Group A than for Groups B and C.Refractive changes within Group A were not significant across the time points of 1wk,1mo,and 3mo.Conversely,both Group B and Group C demonstrated statistically significant shifts toward hyperopia from 1wk to 3mo postsurgery.CONCLUSION:Among the three IOLs examined,the SN6CWS IOL showes the greatest stability during the first 3mo postoperatively.Between 1wk and 3mo after surgery,notable hyperopic shifts are evident in eyes implanted with the MI60 and Aspira-aA IOLs,whereas refractive outcomes remain relatively constant in eyes implanted with SN6CWS IOLs. 展开更多
关键词 effective lens position refraction intraocular lens swept-source optical coherence tomography
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Asymmetric Voltage Vector-based Initial Rotor Position Detection in Four-switch Inverter Fed BLDC Motors 认领 引用
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作者 Xinmin Li Kun Liu +2 位作者 Lu Zhou Tingna Shi Wei Chen 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2026年第1期77-86,共10页
In position-sensorless brushless direct current(DC)motors(BLDCMs)fed by a four-switch three-phase(FSTP)inverter,only two phases are fully controlled,while the remaining phase is tied to the midpoint of the split DC-li... In position-sensorless brushless direct current(DC)motors(BLDCMs)fed by a four-switch three-phase(FSTP)inverter,only two phases are fully controlled,while the remaining phase is tied to the midpoint of the split DC-link capacitors.The voltage pulses required by inductance-based initial position detection can cause unequal discharge of the series capacitors,shifting the neutral-point voltage away from half of DC-link voltage(Udc/2).This neutral-point drift breaks the spatial symmetry of the inverter voltage vectors,so the 360°electrical period can no longer be evenly partitioned into six sectors during initial rotor position detection.To address this issue,this paper proposes a detection-pulse injection sequence that explicitly accounts for the asymmetric voltage vectors of the FSTP inverter.With the proposed sequence,the initial rotor position can be identified within a 30°electrical sector.The method requires no additional voltage or current sensors,and experimental results confirm its feasibility. 展开更多
关键词 Brushless direct current(DC)motor(BLDCM) Four-switch three-phase(FSTP)inverter Asymmetric voltage vector Initial position detection
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Improving Cyclic Positioning Strategy Accuracy of UWB System in Complex Underground Environments 认领 引用
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作者 Bo Cao Mingrui Jiang +3 位作者 Shibo Wang Menglan Li Linghua Cui Biyong Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2026年第4期926-938,共13页
The high-precision automatic positioning technology of the shearer is crucial for the automated and unmanned mining.However,the existing localization approaches commonly deliver inaccurate,unsatisfactory and unreliabl... The high-precision automatic positioning technology of the shearer is crucial for the automated and unmanned mining.However,the existing localization approaches commonly deliver inaccurate,unsatisfactory and unreliable results.In response to this challenge,we propose a novel cyclic positioning strategy to automatically migrate the anchor nodes group(ANG)after the completion of the current cutting operation,thereby achieving long-term period positioning.Meanwhile,we design an innovative technique that appropriately incorporates the shrinkage estimation method based on the minimum mean square error criterion(MMSEC),the improved diversity-guided quantum particle swarm optimization(QPSO),and the extended Kalman filter(EKF)to enhance the localization accuracy of the ultra-wideband(UWB)system in each cycle positioning.Firstly,the cycle positioning strategy and the calculation method of the ANG coordinate position are proposed at the end of fully mechanized mining face.Secondly,the MMSEC method is developed by taking into account of the large measurement noise in the underground environments,and the improved diversity-guided QPSO method is implemented to optimize the result of MMSEC approach.Subsequently,the EKF is executed to suppress the influence of distance residuals on the positioning accuracy and further refine the final estimation accuracy.Lastly,the experimental investigation is performed to evaluate the effectiveness of the proposed cyclic positioning strategy.The experimental results sufficiently demonstrate that the developed MMSEC-QPSO-EKF technique significantly enhances localization accuracy and substantially outperforms the conventional methods,which is capable of achieving better estimation accuracy in each cycle positioning.The proposed cyclic positioning strategy can be successfully implemented,and the achieved accuracies are less than 0.2 m as the ANG is migrated three times,showcasing outstanding localization performance and robustness. 展开更多
关键词 Autonomous positioning diversity-guided quantum particle swarm optimization (QPSO) migration strategy minimum mean square error criterion (MMSEC) underground environment
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基于边际性的超图结构合作博弈上Position值的新刻画 认领 引用
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作者 单而芳 余炳鑫 崔泽光 《运筹与管理》 CSCD 北大核心 2026年第1期99-104,共6页
在可转移效用合作博弈中,YOUNG(1985)提出了“边际性”公理,并将其用于Shapley值的公理化刻画。在图限制博弈中,“PL边际性”作为边际性的一种推广,可以用来刻画Position值。本文进一步将边际性推广到超图结构合作博弈中,提出了“PH边... 在可转移效用合作博弈中,YOUNG(1985)提出了“边际性”公理,并将其用于Shapley值的公理化刻画。在图限制博弈中,“PL边际性”作为边际性的一种推广,可以用来刻画Position值。本文进一步将边际性推广到超图结构合作博弈中,提出了“PH边际性”。通过PH边际性,并结合分支有效性和必要参与者的部分平均超边贡献性,本文给出了超图结构合作博弈上Position值的新刻画。 展开更多
关键词 TU博弈 边际性 超图结构合作博弈 Position值
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Clinical advantages of manual rotation of the fetal head in dystocia during occipito-transverse and occipito-posterior positions 认领 引用
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作者 LI Shenghua 《外文科技期刊数据库（文摘版）医药卫生》 2026年第3期105-109,共5页
Objective: To analyze the clinical efficacy and safety of manual fetal head rotation in managing dystocia with occiput transverse or occiput posterior positions during labor. Methods: A total of 30 cases of mothers wi... Objective: To analyze the clinical efficacy and safety of manual fetal head rotation in managing dystocia with occiput transverse or occiput posterior positions during labor. Methods: A total of 30 cases of mothers with occiput transverse or occiput posterior dystocia admitted to our hospital from January to December 2023 were enrolled as study subjects, divided into an observation group (n=15) and a control group (n=15) based on treatment approach. The observation group received manual fetal head rotation therapy, while the control group underwent conventional expectant management. Comparative analyses were conducted regarding labor progression duration, mode of delivery, and incidence of maternal/fetal complications between the two groups. Results: The first and second stages of labor in the observation group were significantly shorter than those in the control group;the spontaneous delivery rate was higher, and the incidence of maternal/fetal complications was lower, all demonstrating statistically significant differences (<0.05). Conclusion: Manual fetal head rotation is an effective intervention for managing occiput transverse or occiput posterior dystocia during labor, significantly reducing labor duration, improving spontaneous delivery rates, lowering complication rates, and offering a relatively simple and non-invasive procedure. 展开更多
关键词 Manual rotation of fetal head occipito-transverse position occipito-posterior position dystocia clinical efficacy
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Real-Time Machine Learning-Based Position Recognition in Laser Nanofabrication with Sub-Half-Wavelength Precision 认领 引用
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作者 Hao Zhang Jinchuan Zheng +2 位作者 Guiyuan Cao Han Lin Baohua Jia 《Engineering》 SCIE EI CSCD 2026年第2期200-209,共10页
Laser nanofabrication with tightly focused ultrafast laser pulses enable versatile fabrication of arbitrary two-dimensional(2D)hree-dimensional(3D)microanostructures.Accurate positioning of the laser focal spot is cru... Laser nanofabrication with tightly focused ultrafast laser pulses enable versatile fabrication of arbitrary two-dimensional(2D)hree-dimensional(3D)microanostructures.Accurate positioning of the laser focal spot is crucial,especially for high-resolution integrated devices in 2D materials,requiring precise placement on atomically thin surfaces.However,uneven surfaces and surface tilt poses significant challenges.Existing methods to detect focal positions often involve complex setups with additional optical components or sensors,achieving limited accuracy.This study introduces a machine learning-based method to accurately detect the focal position during laser nanofabrication by analyzing the shape and intensity of the laser focal spot.We compare four machine learning methods:rational quadratic Gaussian process regression,kernel approximation least square,quadratic support vector machine,and trilayered neural network.Our experiments show that trilayered neural network(TNN)method achieves a detection accuracy of 257 nm(half the fabrication laser wavelength),surpassing the required accuracy for tightly focused laser beam(typically larger than one wavelength).This method can map focal positions along the fabrication trajectory to compensate for surface roughness or tilt.Moreover,it can be directly implemented in any laser nanofabrication system with a camera for in situ monitoring,without requiring additional optical components,indicating broad applicability. 展开更多
关键词 Laser nanofabrication Machine learning Image-based position recognition Neural network Image processing
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Contribution of x-ray incident position dependence to energy resolution of Ti/Au transition-edge sensors 认领 引用
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作者 Qing-Xiao Ma Wen Zhang +8 位作者 Pei-Zhan Li Zhi-Fa Feng Xian-Feng Zhou Zheng Wang Jia-Qiang Zhong Wei Miao Yuan Ren Jing Li Sheng-Cai Shi 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第3期526-530,共5页
We present the contribution of x-ray incident-position dependence on the absorber to the energy resolution of Ti/Au transition-edge sensors(TESs).The pulse height varies with the position due to insufficient thermal c... We present the contribution of x-ray incident-position dependence on the absorber to the energy resolution of Ti/Au transition-edge sensors(TESs).The pulse height varies with the position due to insufficient thermal conductivity and geometry of the absorber that degrades the measured energy resolution.We develop a three-dimensional(3D)electrothermal simulation model and thoroughly study the position dependent contribution to energy resolution(ΔEp)for two presentative absorber structures:an absorber directly deposited on the center of TES sensor(design A)and an absorber cantilevered on the TES sensor by several stems(design B).For design A with a 30μm×40μm Au absorberΔEpis found to be 9.4 eV,while it is reduced to 1.35 eV for design B with a 100μm×100μm Au absorber.Although the contribution of position dependence is relatively small,this study facilitates further optimization of the absorber structure to achieve enhanced energy resolution. 展开更多
关键词 transition-edge sensors electro-thermal simulation position dependence energy resolution
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Effect of fluorination positions at diphenylamino flanking groups on the photovoltaic performance for nonfused ring electron acceptors 认领 引用
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作者 Yang Gao Huarui Zhang +7 位作者 Yan Xie Xinjun Xu Yahui Liu Hao Lu Wenkai Zhang Yuqiang Liu Cuihong Li Zhishan Bo 《Chinese Chemical Letters》 SCIE CAS CSCD 2026年第1期368-373,共6页
The fluorination strategy has been proven effective in significantly enhancing the photovoltaic performance of organic solar cells(OSCs) based on non-fused ring electron acceptors(NFREAs).However,research on the impac... The fluorination strategy has been proven effective in significantly enhancing the photovoltaic performance of organic solar cells(OSCs) based on non-fused ring electron acceptors(NFREAs).However,research on the impact of fluorination positions at side chains on NFREAs device performance remains scant.In this study,we introduce two isomeric NFREAs,designated as GA-2F-E and GA-2F,distinguished by their fluorination positions at the side chains.Both NFREAs share a thiophene[3,2-b]thiophene core,but their side chains differ:GA-2F-E features two(4-butylphenyl)-N-(4-fluorophenyl) amino groups,whereas GA-2F's side chains consist of bis(4-fluorophenyl)amino and bis(4-butylphenyl)amino groups attached to opposite sides of the core.To delve into the influence of fluorination positions on the optoelectronic properties,aggregation behavior,and overall efficiency of the acceptor molecules,a comprehensive investigation was conducted.The findings reveal that,despite similar photophysical properties and comparable absorption bandwidths,GA-2F-E,with fluorine atoms positioned on both sides of the molecular framework,demonstrates more compact π-π stacking,reduced bimolecular recombination,superior exciton transport,and a more balanced,higher mobility.As a result of these advantages,OSCs optimized with D18:GA-2F-E achieve a remarkable power conversion efficiency(PCE) of 16.45 %,surpassing the 15.83 %PCE of devices utilizing D18:GA-2F.This research underscores the potential of NFREAs in future applications and highlights the significance of fluorination positions in enhancing OSC performance,paving the way for the development of more efficient NFREAs. 展开更多
关键词 Organic solar cells Non-fused ring electron acceptors Fluorination position Diphenylamino groups Power conversion efficiencies
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Design and analysis of modular truss deployable antenna mechanism based on tetrahedral basic unit mechanism with dual height positioning nodes 认领 引用
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作者 Enbo LIU Yongsheng ZHAO +5 位作者 Tengfei CAO Shudan LI Bo CHEN Xinlu WEI Yundou XU Jiantao YAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第2期593-608,共16页
Modular truss space deployable antennas are key for future large aperture,high precision antennas,already proven in various in-orbit applications globally.This paper introduces a design method for a tetrahedral basic ... Modular truss space deployable antennas are key for future large aperture,high precision antennas,already proven in various in-orbit applications globally.This paper introduces a design method for a tetrahedral basic unit mechanism with dual height positioning nodes.A parametric model is established,and its DOF are analyzed to confirm the mechanism's validity.The new tetrahedral basic unit mechanism constructed by this method is a single DOF mechanism and can locate different parabolic node heights.In order to further adapt to the parabolic and large aperture requirements of the deployable antenna of the truss,a combination unit and modular unit mechanism are developed based on this tetrahedral unit.The DOF and deployment characteristics of the modular unit mechanism are analyzed and validated through simulations.Various networking methods for the modular units are proposed,followed by a comprehensive performance comparison of different modular truss deployable antenna mechanisms.A prototype model of the modular unit mechanism is also developed,with deployment experiments demonstrating the mechanism's simplicity,low DOF,and large deployment ratio.The findings of this study provide a theoretical and technical basis for the future design and development of truss deployable antenna mechanisms. 展开更多
关键词 Degree of freedom(DOF) Deployable truss antenna Dual height node positioning Modularity Screw theory Tetrahedral unit
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Lightweight Complex-Valued Neural Network for Indoor Positioning 认领 引用
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作者 Le Wang Bing Xu +1 位作者 Peng Liu En Yuan 《Computers, Materials & Continua》 SCIE EI 2026年第2期1770-1783,共14页
Deep learning has been recognized as an effective method for indoor positioning.However,most existing real-valued neural networks(RVNNs)treat the two constituent components of complex-valued channel state information(... Deep learning has been recognized as an effective method for indoor positioning.However,most existing real-valued neural networks(RVNNs)treat the two constituent components of complex-valued channel state information(CSI)as real-valued inputs,potentially discarding useful information embedded in the original CSI.In addition,existing positioning models generally face the contradiction between computational complexity and positioning accuracy.To address these issues,we combine graph neural network(GNN)with complex-valued neural network(CVNN)to construct a lightweight indoor positioning model named CGNet.CGNet employs complexvalued convolution operation to directly process the original CSI data,fully exploiting the correlation between real and imaginary parts of CSI while extracting local features.Subsequently,the feature values are treated as nodes,and conditional position encoding(CPE)module is applied to add positional information.To reduce the number of connections in the graph structure and lower themodel complexity,feature information is mapped to an efficient graph structure through a dynamic axial graph construction(DAGC)method,with global features extracted usingmaximum relative graph convolution(MRConv).Experimental results show that,on the CTW dataset,CGNet achieves a 10%improvement in positioning accuracy compared to existing methods,while the number of model parameters is only 0.8 M.CGNet achieves excellent positioning accuracy with very few parameters. 展开更多
关键词 Indoor positioning complex-valued neural network channel state information lightweight model
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Multi-System Real-Time Kinematic Positioning Based on Fast Satellite Selection and Improved Kalman Filter 认领 引用
19
作者 TANG Haibo WAN Bohan MAO Xuchu 《Journal of Shanghai Jiaotong university(Science)》 EI 2026年第4期992-1002,I0016,共11页
In optimal observation conditions,the number of visible satellites from the four global navigation satellite systems(GNSSs)can rise to approximately 50.This substantially elevates the computational demands for positio... In optimal observation conditions,the number of visible satellites from the four global navigation satellite systems(GNSSs)can rise to approximately 50.This substantially elevates the computational demands for position determination.To expedite position calculations without compromising accuracy,we introduce a rapid satellite selection algorithm that merges the geometric distribution approach with the transformation formula technique.The dynamic environment presents more challenges compared with static positioning,being both intricate and less consistent.To bolster the precision and robustness of kinematic positioning,we present a four-GNSS fusion positioning algorithm grounded in the extended Kalman filter.Experimental results indicate that our proposed methodologies can attain centimeter-level precision and enhance computational efficiency. 展开更多
关键词 real-time kinematic extended Kalman filter ambiguity resolution least-squares ambiguity decorrelation adjustment kinematic positioning
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Reducing fluoroscopy in acromioclavicular joint reconstruction:Clinical value of the three-point positioning technique 认领 引用
20
作者 Musa Ergin Mehmet Ertanıdır 《World Journal of Orthopedics》 2026年第5期1-5,共5页
Acromioclavicular joint dislocation(ACJD)is one of the shoulder girdle injuries that particularly affects young and active individuals.Although various surgical techniques have been developed for coracoclavicular liga... Acromioclavicular joint dislocation(ACJD)is one of the shoulder girdle injuries that particularly affects young and active individuals.Although various surgical techniques have been developed for coracoclavicular ligament reconstruction,TightRope fixation has gained popularity.The procedure relies on frequently repeated intraoperative fluoroscopy to ensure the accuracy of tunnel placement,which increases radiation exposure for both patients and surgical teams.In the recent issue of World Journal of Orthopedics,Chen et al present a novel three-point positioning technique designed to guide tunnel trajectory and implant placement while reducing fluoroscopy time during TightRope fixation.Their retrospective analysis of patients with acute Rockwood type III ACJD demonstrated favorable functional outcomes and,in particular,low intraoperative fluoroscopy exposure.In this editorial,we discuss the clinical significance of radiation reduction in shoulder surgery and highlight the importance of procedural innovations that improve surgical workflow without increasing technical complexity.Simplified intraoperative positioning strategies may represent an important step toward safer and more efficient minimally invasive acromioclavicular joint reconstruction.Furthermore,techniques that minimize radiation exposure while maintaining surgical precision may contribute to improved occupational safety in orthopedic practice.Such practical innovations could play an important role in the future evolution of image-guided shoulder surgery. 展开更多
关键词 Acromioclavicular joint dislocation TightRope fixation Fluoroscopy reduction Three-point positioning technique Coracoclavicular stabilization Shoulder surgery
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