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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

A fuse-based DC circuit breaker with vacuum interrupter enhanced by an external transverse magnetic field

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High Voltage 2024年第3期9卷 710-720页

作者： Yu Xiao Yi wu Yifei wu Fei yang Mingzhe Rong Zhuo yang State Key Laboratory of Electrical Insulation and Power Equipment School of Electric EngineeringXi'an Jiaotong UniversityXi'anChina State Grid Shaanxi Electric Power Company Limited Xi'anChina

Due to the increasing power system capacity,the interruption of large fault currents has gradually become a major challenge in power *** the moment,such currents are interrupted mainly via circuit breakers based on the method of active current ***,these types of circuit breakers tend to be costly and *** possible alternative—a fuse-based circuit breaker with current commutation process enhanced by an external transverse magnetic field(ETMF)—is proposed by the *** main advantage lies in the fast current commutation achieved by an ETMF-enhanced three-stage increase of the vacuum arc *** study of the current commutation process is mainly represented by the authors,and the influencing factors of the current commutation—contact opening speed and ETMF current—are *** last,the proposed circuit breaker is verified by an experiment,whose results show that a short-circuit current of 42 kA can be interrupted within just 2 ms.

关键词： vacuum transverse interrupt

ERGODIC CAPACITY ANALYSIS FOR SIMO COGNITIVE FADING CHANNEL IN SPECTRUM SHARING ENVIRONMENT

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Journal of Electronics(China) 2010年第5期27卷 677-685页

作者： yang yang Wang Jinlong wu Qihui Liu Xin Institute of Communication Engineering PLA University of Science and Technology Nanjing 210007China

In this paper,we consider the spectrum sharing Cognitive Radio(CR) system,wherein Single-Input Multi-Output(SIMO) cognitive fading channel is *** to the average in-terference constraint of primary user,the ergodic capacity of cognitive user involving joint beamforming and power control is *** derive the optimal joint beamforming and power control strategy and deduce the general integral expression for ergodic ***,under different channel fadings including Raleigh fading,Nakagami-m fading and Lognormal shadowing fading,the specific expressions of ergodic capacity for SIMO cognitive channel are *** of the expressions are presented in closed-form or with some special integral *** amount of simulations are conducted to corroborate our theoretical results.

关键词： Cognitive Radio (CR) Beamforming Power control Ergodic capacity Single-Input Multi-Output (SIMO)

Conduction-convection coupled heat transfer around a hollow cylinder under different buoyancy forces

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Chinese Journal of Aeronautics 2024年第4期37卷 216-228页

作者： Wanyu ZHANG Jingyi wu Guang yang Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China

In order to clarify the effect of a buoyancy force on conduction–convection coupled heat transfer in a hollow cylinder, the flow and thermal characteristics were analyzed using an RNG k-ε turbulence model. The Reynolds number was fixed at 1.014 × 10^(6), and the Rayleigh number varied from 1.122 × 10^(10)to 1.088 × 10^(11). Results have shown that, when considering the effect of an opposed buoyancy force, increasing the Rayleigh number has a positive impact on the rate of change and uniformity of the cylinder temperature. The temperature distributions along the axial and circumferential directions are similar for different Rayleigh numbers, but extreme values *** the axial direction, the maximum temperature is obtained at the interface between the variable-diameter part and the constant-diameter part. The maximum dimensionless temperature value decreases to 0.12 when the Rayleigh number increases to 1.088 × 10^(11). Along the circumferential direction, the temperature distribution is affected by the buoyancy force, which results in the temperature of the upper part being higher than that of the lower part. After nondimensionalization of the temperature and time, a correlation was proposed to illustrate the transient heat transfer process quantitatively. The standard deviation of the maximum relative temperature, representing the temperature uniformity, was also calculated. It was found that the difference in the direction of the buoyancy force made a huge difference. Compared with the opposed buoyancy force, the maximum dimensionless temperature is almost two times higher with an assisted buoyancy force. Similarly, the heat transfer coefficient with an assisted buoyancy force is half of that with an opposed buoyancy force. Overall, an assisted buoyancy force plays a negative role in terms of thermal characteristics. The flow field around the hollow cylinder was also illustrated to reveal the mechanism of the buoyancy force on magnitude and direction aspects

关键词： Buoyancy Conduction-convection heat transfer Transient analysis Hollow cylinder Non-dimensionalization

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

Two-dimensional semiconductor heterostructures for photocatalytic CO_(2)conversion

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Science China Chemistry 2024年第8期67卷 2434-2447页

作者： yang wu Mingyu wu Yongfu Sun Yi Xie Hefei National Research Center for Physical Sciences at Microscale University of Science and Technology of ChinaHefei 230026China

The CO_(2)reduction into carbon-contained fuel via solar energy offers the powerful tools to realize the zero-emission carbon *** to the intriguing features of the two-dimensional(2D)heterostructures,it is susceptible to modulate the electronic structure as well as the surface geometry for optimizing the photocatalytic CO_(2)*** this perspective,we surveyed the fundamental insights of 2D semiconductor heterostructures,involving the fabrication strategies and classification of the 2D semiconductor ***,we have detailly discussed the overview of 2D semiconductor heterostructure for optimizing CO_(2)photocatalytic influenced factors,including the solar energy utilization,photogenerated carriers separation,and redox reaction ***,we showed the significant advantages of 2D heterostructures in elevating CO_(2)photoreduction performance,focusing on activity,selectivity and *** analyzing the limitations and developments,we ended by putting forward insights into the further researches about the CO_(2)photocatalysts and reactor design,even industrial applications.

关键词： two-dimensional semiconductor heterostructures photocatalysis CO_(2)conversion