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油气生产物联网技术标准研究与应用

中国标准化 2024年第4期 132-136页

作者：姚刚杨午阳吴海莉中国石油勘探开发研究院西北分院

科技创新是引领发展的第一动力,物联网系统建设是能源企业实现数字化转型、智能化发展的重要依托。本文阐述了新时期油气生产物联网技术标准研究工作的急迫性,通过对标准的研究与实践,论述了油气生产物联网系统技术标准的研究方法和应... 详细信息

科技创新是引领发展的第一动力,物联网系统建设是能源企业实现数字化转型、智能化发展的重要依托。本文阐述了新时期油气生产物联网技术标准研究工作的急迫性,通过对标准的研究与实践,论述了油气生产物联网系统技术标准的研究方法和应用成效。

关键词：油气生产物联网技术标准应用

Resource allocation for D2D-assisted haptic communications

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Digital Communications and Networks 2024年第1期10卷 63-74页

作者： Yan wu Chao Yue yang yang Liang Ao College of Telecommunication Engineering Army Engineering University of PLANanjing210000China

Haptic communications is recognized as a promising enabler of extensive services by enabling real-time haptic control and feedback in remote environments,e.g.,teleoperation and autonomous *** the strict transmission requirements on reliability and latency,Device-to-Device(D2D)communications is introduced to assist haptic *** particular,the teleoperators with poor channel quality are assisted by auxiliaries,and each auxiliary and its corresponding teleoperator constitute a D2D ***,the haptic interaction and the scarcity of radio resources pose severe challenges to the resource allocation,especially facing the sporadic packet ***,the contentionbased access scheme is applied to achieve low-latency transmission,where the resource scheduling latency is omitted and users can directly access available *** this context,we derive the reliability index of D2D pairs under the contention-based access scheme,i.e.,closed-loop packet error ***,the reliability performance is guaranteed by bidirectional power control,which aims to minimize the sum packet error probability of all D2D *** game theory is introduced to solve the problem with low ***,a distributed power control algorithm based on synchronous log-linear learning is proposed to converge to the optimal Nash *** results demonstrate the superiority of the proposed learning algorithm.

关键词： Haptic communications D2D Power control Contention-based access Potential game

Intelligent feedforward gust alleviation based on neural network

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Chinese Journal of Aeronautics 2024年第3期37卷 116-132页

作者： Yitao ZHOU Zhigang wu Chao yang School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

This paper proposes a neural network-based intelligent feedforward gust alleviation framework,which includes a neural network identification model and a neural network controller.A neural network training dataset is formed by collecting flight data and the gust data encountered during the aircraft flight.A neural network identification model is first trained to accurately predict the aircraft’s ***,based on the output of the identification model and the collected flight data,the parameters of the time-delay neural network controller are obtained through a learning *** simulation results show that the designed intelligent controller has good gust alleviation effects for both continuous turbulence excitation and discrete gust *** example,when the aircraft is 40000 kg and the flight speed is 0.81Ma,the controller achieves a 67.82%reduction in wingtip acceleration and a 35.90%reduction in center of mass acceleration under continuous turbulence *** considering the measurement uncertainties,such as noise existing in the collected data,the trained controller can still achieve an acceptable gust alleviation ***,considering a flight in which the aircraft mass is constantly changing,the intelligent controller,which continuously learns from new flight data,maintains a good gust alleviation effect throughout the flight.

关键词： Gust alleviation Intelligent control Feedforward control Neural networks Time-varying aircraft

Active flutter suppression of nonlinear fin-actuator system via inverse system and immersion and invariance method

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Chinese Journal of Aeronautics 2024年第4期37卷 343-362页

作者： Jin LU Zhigang wu Chao yang Chinese Aeronautical Establishment Beijing 100029China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

Structural nonlinearities such as freeplay will affect the stability and even flight safety of the fin-actuator *** is a lack of a practical method for designing Active Flutter Suppression (AFS) control laws for nonlinear fin-actuator systems.A design method for the AFS controller of the nonlinear all-movable fin-electromechanical actuator system is established by combining the inverse system and the Immersion and Invariance (I&I) ***,the composite control law combining the inverse system principle and internal model control is used to offset the nonlinearity and dynamics of the actuator,so that its driving torque can follow the ideal ***,the ideal torque of the actuator is designed employing the I&I *** unfavorable oscillation of the fin is suppressed by making the output torque of the actuator track the ideal *** simulation results reveal that the proposed AFS method can increase the flutter speed of the nonlinear finactuator system with freeplay,and a set of controller parameters is also applicable for wider freeplay within a certain *** power required for the actuator does not exceed the power that can be provided by the commonly used aviation *** method can also resist a certain level of noise and external disturbance.

关键词： Aeroelasticity Active flutter suppression Fin-actuator system Freeplay Inverse system Immersion and invariance

Retrolaminar migration as a complication of intraocular silicone oil injection detected on unenhanced CT

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International Journal of Ophthalmology(English edition) 2023年第9期16卷 1521-1526页

作者： Fan-Fan Zhao Ya-Ling Pan Hui Jin yang-yang wu Yu-Ting Yan Yu Meng Xiang-yang Gong Center for Rehabilitation Medicine Department of RadiologyZhejiang Provincial People’s Hospital(Affiliated People’s Hospital)Hangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina Center for Rehabilitation Medicine Department of OphthalmologyZhejiang Provincial People’s Hospital(Affiliated People’s Hospital)Hangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina Institute of Artificial Intelligence and Remote Imaging Hangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina

AIM:To describe the clinical and radiologic features of retrolaminar migration silicone oil(SiO)and observe the dynamic position of ventricular oil accumulation in supine and ***:For this retrospective study,29 patients who had a history of SiO injection treatment and underwent unenhanced head computed tomography(CT)were included from January 2019 to October *** patients were divided into migration-positive and negative *** history and CT features were compared using Whitney U and Fisher’s exact *** dynamic position of SiO was observed within the ventricular system in supine and *** images were visually assessed for SiO migration along the retrolaminar involving pathways for vision(optic nerve,chiasm,and tract)and ventricular ***:Intraocular SiO migration was found in 5 of the 29 patients(17.24%),with SiO at the optic nerve head(n=1),optic nerve(n=4),optic chiasm(n=1),optic tract(n=1),and within lateral ventricles(n=1).The time interval between SiO injection and CT examination of migration-positive cases was significantly higher than that of migration-negative patients(22.8±16.5mo vs 13.1±2.6mo,P<0.001).The hyperdense lesion located in the frontal horns of the right lateral ventricle migrated to the fourth ventricle when changing the position from supine to ***:Although SiO retrolaminar migration is unusual,the clinician and radiologist should be aware of migration *** supine combined with prone examination is the first-choice method to confirm the presence of SiO in the ventricular system.

关键词： retrolaminar migration silicone oil tamponade unenhanced head computed tomography supine and prone computed tomography

Modeling wave propagation across rock masses using an enriched 3D numerical manifold method

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Science China(Technological Sciences) 2024年第3期67卷 835-852页

作者： yang YongTao LI JunFeng wu WenAn State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China University of Chinese Academy of Sciences Beijing 100049China

The three-dimensional numerical manifold method(3DNMM) method is further enriched to simulate wave propagation across homogeneous/jointed rock masses. For the purpose of minimizing negative effects from artificial boundaries, a viscous nonreflecting boundary, which can effectively absorb the energy of a wave, is firstly adopted to enrich 3DNMM. Then, to simulate the elastic recovery property of an infinite problem domain, a viscoelastic boundary, which is developed from the viscous nonreflecting boundary, is further adopted to enrich 3DNMM. Finally, to eliminate the noise caused by scattered waves, a force input method which can input the incident wave correctly is incorporated into 3DNMM. Five typical numerical tests on P/S-wave propagation across jointed/homogeneous rock masses are conducted to validate the enriched 3DNMM. Numerical results indicate that wave propagation problems within homogeneous and jointed rock masses can be correctly and reliably modeled with the enriched 3DNMM.

关键词： 3D numerical manifold method viscous nonreflecting boundary rock masses force input method wave propagation

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On the size generalizibility of graph neural networks for learning resource allocation

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Science China(Information Sciences) 2024年第4期67卷 239-254页

作者： Jiajun wu Chengjian SUN Chenyang yang Beihang University School of Electronics and Information Engineering

Size generalization is important for learning resource allocation policies in wireless systems with time-varying scales. If a neural network for learning a wireless policy is not generalizable to the size of its input, it has to be re-trained whenever the system scale changes, which hinders its practical use due to the unaffordable training costs. Graph neural networks(GNNs) have been shown with size generalization ability empirically when optimizing resource allocation. Yet, are GNNs naturally size generalizable? In this paper,we argue that GNNs are not always size generalizable for resource allocation. We find that the aggregation and activation functions of the GNNs for learning a class of wireless policies play a key role in their size generalization ability. We take the GNN with the mean aggregator, called mean-GNN, as an example to reveal a size generalization condition. To demonstrate how to satisfy the condition, we learn power and bandwidth allocation policies for ultra-reliable low-latency communications and show that selecting or pretraining the activation function in the output layer of mean-GNN can make the GNN size *** results validate our analysis and evaluate the performance of the learned policies.

关键词： size generalization graph neural networks resource allocation permutation equivariance

Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments

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Chinese Journal of Polymer Science 2024年第4期42卷 511-520页

作者： Tian-Hao yang Tong wu Qiang Fu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu610065China

Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关键词： Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment

Super-Resolution Fluorescence Microscopy for Cilia Investigation and Ciliopathy Diagnosis(Invited)

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激光与光电子学进展 2024年第6期61卷 260-271页

作者： Liu Zhen wu yang Division of Life Science The Hong Kong University of Science and TechnologyHong KongChina

The last two decades have witnessed the invention and development of super-resolution microscopy(SRM)that breaks the diffraction limit of light and pushes the fluorescence microscopy resolution to several *** SRM is widely used in biological studies,such as resolving subdiffraction structures,molecular mapping,tracking single molecules,probing protein-protein interactions,and observing organelle dynamics,its direct application in translational medicine,such as disease diagnosis,is still *** their small size,cilia play a crucial role as organelles in cell signaling and motility,with defects in cilia leading to *** to other miniature organelles and macromolecular complexes,cilia are ideal for super-resolution *** this review,we will 1)introduce cilia and ciliopathy,2)show how SRM extends our knowledge of cilia,and 3)focus on how SRM improves the diagnosis of motile ciliopathies.

关键词： diagnosis limit spite