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Cyclicity of the Lower Buntsandstein in the eastern part of the Central European Basin:implications for Early Triassic palaeogeography and for geochronological calibration

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Journal of Palaeogeography 2024年第2期13卷 252-292页

作者： Anna Becker Polish Geological institute-National research institute 4 Rakowiecka str.00-975 WarsawPoland

Lower Buntsandstein small—scale cycles recognized in the Central European Basin(CEB) are readily used for astrochronological calibration of the Early Triassic time scales,although they are not well studied *** borehole sections from the eastern part of the CEB,forming a south-north transect perpendicular to the basin axis,were studied in terms to better understand the depositional history of the Lower Buntsandstein developed as the Baltic Formation in the studied Polish part of the *** sedimentary facies were recognized,based on lithological and sedimentological investigations of 655.7 m of drill cores from the Otyń IG 1,Gorzów Wielkopolski IG 1 and Kamień Pomorski IG 1 *** facies can be grouped according to a lithological criterion into facies of predominantly siliciclastic lithology(including 9facies types) and facies of predominantly carbonate lithology(including 2 facies types).Facies analysis allowed to distinguish 8 facies associations of:1) alluvial fan,2) playa,3) sandy-muddy coastal plain,4)embayment and distal delta,5) lagoon,6) sand bars or shoals,7) ooidal shoals or bars,and 8) ***-upward(DC) and shallowing-upward(SC) sedimentary cycles were recognized in parts of the Baltic Formation,with DCs dominating in the southernmost located Otyń IG 1,and SCs dominating in Gorz ow Wielkopolski IG 1,located in the axial part of the *** cycles are very *** statistical significance of the sedimentary cycles is relatively low according to Markov-chain analysis conducted with the phpSedistat software of Stanova et al.(2009).Analysis of small—scale cycles performed on well logs of investigated boreholes and additional boreholes in the vicinity of Otyń IG 1,implementing the earlier study of Becker(2005),showed that the correlation of well-log cycles(GR cycles) and sedimentary cycles is not *** cycles can be roughly correlated with lithological carbonate—siliciclastic cycles(c-s cycles),refle

关键词： Triassic Lower Buntsandstein Cyclicity Central European Basin

A novel matrix topology-based analysis method of thermal circuits for reliability optimization of HSER

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Chinese Journal of Aeronautics 2024年第4期37卷 479-492页

作者： Huimin LIANG Bo LI Jiaxin YOU Shan JIANG Mengtong ZHU Aobo WANG Department of Electrical Engineering Harbin Institute of TechnologyHarbin 150001China Nanjing research institute of Electronics Technology Nanjing 210008China

Hermetically Sealed Electromagnetic Relay(HSER), used in aviation and aerospace,demands high reliability due to its critical applications. Given its complex operating conditions, efficient thermal analysis is essential for optimizing reliability. The commonly used Finite Element Method(FEM) is often time-consuming and may not be efficient or adaptable for complex multi-dimensional system calculations and design processes. This paper introduces an analysis method for thermal networks based on matrix perspective technology, encompassing matrix transformation, backpropagation of the heat path model, temperature rise calculation, solution comparison, and product implementation. Using the similarity theory of heat circuits, a basic thermal unit is established. Based on the fundamental connection between key components, a thermal network for a typical HSER is designed. An experimental system is set up, and the thermal network model's accuracy is confirmed using test data. Employing the topology analysis method, the topology of the thermal network is analyzed under both coil-energized and de-energized states. Potential thermal paths are identified, leading to optimized solutions for the HSER. Utilizing these solutions, the thermal path matrix topology model is backpropagated to the thermal path for temperature rise calculations. When compared to prototype HSER test data, the efficiency and accuracy of this matrix topology-based analysis method are confirmed.

关键词： Thermal networks HSER(Hermetically Sealed Electromagnetic Relay) Heat-circuit topology model Heat-circuit matrix Optimization design

Damping Characteristic Analysis and Optimization of Wind-thermal-bundled Power Transmission by LCC-HVDC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 299-312页

作者： Liwen Zheng Shiying Ma the Power System Department China Electric Power Research InstituteBeijing 100192China

With the rapid development of renewable energy,wind-thermal-bundled power transmission by line-commutated converter based high-voltage direct current(LCC-HVDC)systems has been widely *** dynamic interaction mechanisms among permanent magnet synchronous generators(PMSGs),synchronous generators(SGs),and LCC-HVDC system become *** deal with this issue,a path analysis method(PAM)is proposed to study the dynamic interaction mechanism,and the damping reconstruction is used to analyze the damping characteristic of the ***,based on the modular modeling,linearized models for the PMSG subsystem,the LCC-HVDC subsystem,and the SG subsystem are ***,based on the closed-loop transfer function diagram of the system,the disturbance transfer path and coupling relationship among subsystems are analyzed by the PAM,and the damping characteristic analysis of the SG-dominated oscillation mode is studied based on the damping *** with the PAM,the small-signal model of the system is obtained and eigenvalue analysis results are ***,the effect of the control parameters on the damping characteristic is analyzed and the conclusions are verified by time-domain ***,the penalty functions of the oscillation modes and decay modes are taken as the objective function,and an optimization strategy based on the Monte Carlo method is proposed to solve the parameter optimization *** simulation results are presented to validate the effectiveness of the proposed strategy.

关键词： Wind-thermal-bundled power transmission line-commutated converter based high-voltage direct current(LCC-HVDC) path analysis method(PAM) damping characteristic analysis Monte Carlo method

Abnormal Traffic Detection for Internet of Things Based on an Improved Residual Network

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Computers, Materials & Continua 2024年第6期79卷 4433-4448页

作者： Tingting Su Jia Wang Wei Hu Gaoqiang Dong Jeon Gwanggil School of Computer Science and Technology Xinjiang UniversityUrumqi830046China School of cyber Science and Engineering Jinling Institute of Technology CityNanjing210000China College of Information Technology Incheon National UniversityIncheon22012Korea

Along with the progression of Internet of Things(IoT)technology,network terminals are becoming continuously more *** has been widely applied in various scenarios,including urban infrastructure,transportation,industry,personal life,and other socio-economic *** introduction of deep learning has brought new security challenges,like an increment in abnormal traffic,which threatens network *** feature extraction leads to less accurate classification *** abnormal traffic detection,the data of network traffic is high-dimensional and *** data not only increases the computational burden of model training but also makes information extraction more *** address these issues,this paper proposes an MD-MRD-ResNeXt model for abnormal network traffic *** fully utilize the multi-scale information in network traffic,a Multi-scale Dilated feature extraction(MD)block is *** module can effectively understand and process information at various scales and uses dilated convolution technology to significantly broaden the model’s receptive *** proposed Max-feature-map Residual with Dual-channel pooling(MRD)block integrates the maximum feature map with the residual *** module ensures the model focuses on key information,thereby optimizing computational efficiency and reducing unnecessary information *** results show that compared to the latest methods,the proposed abnormal traffic detection model improves accuracy by about 2%.

关键词： Abnormal network traffic deep learning residual network multi-scale feature extraction max-feature-map

Optimizing evasive maneuvering of planes using a flight quality driven model

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Science China(Information Sciences) 2024年第3期67卷 197-208页

作者： Chang LIU Shaoshan SUN Chenggang TAO Yingxin SHOU Bin XU School of Automation Northwestern Polytechnical University Chengdu Aircraft Design & research institute of AVIC

This paper investigates the optimal evasive maneuver for a plane to avoid an incoming missile. To accurately model the system dynamics while improving computational efficiency, a simplified plane model based on flight quality is established. A missile model with proportional guidance is also *** problem of determining the optimal evasion plane maneuver is formulated. The Gauss pseudospectral method(GPM) is proposed as a solution to find the optimal maneuver. The optimized maneuver is validated by testing it on a high-fidelity 6-degree-of-freedom(6-DOF) model, which demonstrates the effectiveness of the proposed simplified plane model. The Monte Carlo method is employed to evaluate the capability of the plane to evade missiles in various scenarios and elucidate general principles for successful evasion.

关键词： optimal maneuver flying quality evasive strategy pursuit-evasion game air-to-air combat

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Gradient honeycomb metastructure with broadband microwave absorption and effective mechanical resistance

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Nano Materials Science 2024年第4期6卷 456-466页

作者： Dongmeng Li Xia Zheng Hao Gu Xiaobo Xuan Bing Liu Hongquan Feng Fuheng Zhang Shanghai Radio Equipment research institute

Multifunctional metastructure integrated broadband microwave absorption and effective mechanical resistance has attracted much attention. However, multifunctional performance is limited by the lack of theoretical approaches to integrated design. Herein, a multi-layer impedance gradient honeycomb(MIGH) was designed through theoretical analysis and simulation calculation, and fabricated using 3D printing technique. A theoretical calculation strategy for impedance gradient structure was established based on the electromagnetic parameter equivalent method and the multi-layer finite iterative method. The impedance of MIGH was analyzed by the theoretical calculation strategy to resolve the broadband absorption. Intrinsic loss mechanism of matrix materials and distributions of electric fields, magnetic fields and power loss were analyzed to investigate the absorption mechanism. Experimental results indicated that a 15 mm thick designed metastructure can achieve the absorption more than 88.9% in the frequency range of 2-18 GHz. Moreover, equivalent mechanical parameters of MIGH was calculated by integral method according to the Y-shaped model. Finite Element analysis of stress distributions were carried out to predict the deformation behavior. Mechanical tests demonstrate that MIGH achieved the compression modulus of 22.89 MPa and flexure modulus of 17.05 MPa. The integration of broadband electromagnetic absorption and effective mechanical resistance was achieved by the proposed design principle and fabrication methodology.

关键词： Multifunctional metastructure Broadband microwave absorption Impedance gradient calculation Mechanical characteristics Finite element analysis

Combined Effect of Temperature and Cadmium on Molecular Responses of Hsp70 and P-gp Genes in Crassostrea gigas

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Journal of Ocean University of China 2024年第4期23卷 1115-1120页

作者： HU Fanguang SUN Ming LIU Guangbin JING Yuanyuan CHEN Qun ZHANG Tianwen Marine Science research institute of Shandong Province Qingdao 266104China

To evaluate the combined effect of temperature and cadmium on the molecular responses of heat shock protein 70(hsp70)and P-glycoprotein(P-gp)in mantle,digestive gland and gills of Crassostrea gigas,oysters were exposed to combinations of five temperature levels(10,15,20,25,and 30℃)and 10μg L^(-1)cadmium for 21 *** were sampled for mRNA quantification by qPCR,and the results showed that the P-gp gene expression changed significantly after treatment at different temperatures and different treatment *** P-gp gene expression was the highest in the digestive *** with the control group,the P-gp gene expression in cadmium treatment groups at all the different temperatures were significantly higher than the control *** control oysters(kept at 10℃during the whole experiment without cadmium)expressed low levels of hsp70,but the groups treated with cadmium displayed somewhat higher *** present study demonstrated hsp70 and P-gp played an important role in the detoxification of Cd in ***,and confirmed temperature should be considered for the assessment of Cd-induced toxicity in oysters.

关键词： temperature cadmium P-gp hsp70 Crassostrea gigas

Theory and practice of hull dynamic deformation law and heading angle transfer error correction

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Journal of Ocean Engineering and Science 2024年第2期9卷 191-198页

作者： Yepin Qu Jianqiang Liu Yuhai Lyu Chaoran Zhang Tao Li Naval research institute Shanghai 200436PR China

In order to meet the demand of high-precision heading angle transmission in the transfer alignment of inertial navigation system on moving base,the analytical function relationship between the hull deforma-tion and the turning angular velocity and angular acceleration was derived by using the classical beam theory based on the analysis of the equivalent load exerted by the hydrodynamic force and inertia force on the hull structure during the turning process under the combined action of the steering rudder mo-ment and wave *** objective law between the angular motion and the azimuth deformation angle of the hull under the combined action of maneuvering and sea waves was ***,the correc-tion coefficients were determined according to the left turn and right turn motions of the hull by using the measured data of the ship in the sea trial during the S-shape maneuvering navigation,and the az-imuth deformation angle correction was *** results indicated that the application of the Qu’s bending deformation correction formula could greatly reduce the influence of the hull flexural deforma-tion on the heading angle accuracy,meet the needs of high-precision heading angle transmission,and fully verify the correctness of the hull azimuth deformation law and the heading angle transmission er-ror correction *** theory and method provided technical support for establishing high-precision distributed digital reference in the field of transfer alignment of inertial navigation on moving base and the application of heading angle transfer of other shipborne equipment.

关键词： Hull deformation Hull girder Heading angle Alignment on moving Base Transfer alignment Error correction

Horizontal well spacing optimization and gas injection simulation for the ultra-low-permeability Yongjin reservoir

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Energy Geoscience 2024年第1期5卷 196-203页

作者： Yao Zhang Chengyuan Lv Zengmin Lun Shuxia Zhao Yingfu He Ran Gao SINOPEC Exploration and Production research institute BeijingChina

Optimal spacing for vertical wells can be effectively predicted with several published methods,but methods suitable for assessing the proper horizontal well spacing are *** work proposes a method for calculating the optimal horizontal well spacing for an ultra-low permeability reservoir e the Yongjin reservoir in the Juggar Basin,northwestern *** result shows that a spacing of 640m is the most economical for the development of the *** better develop the reservoir,simulation approaches are used and a new model is built based on the calculated well *** the reservoir has an ultralow permeability,gas injection is regarded as the preferred enhanced oil recovery(EOR)*** of different gases including carbon dioxide,methane,nitrogen and mixed gas are *** results show that carbon dioxide injection is the most efficient and economical for the development of the ***,if the reservoir produces enough methane,reinjecting methane is even better than injecting carbon dioxide.

关键词： Ultra-low-permeability reservoir Well spacing optimization Numerical simulation Gas injection EOR