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Predicting impact forces on pipelines from deep-sea fluidized slides:A comprehensive review of key factors

International Journal of Mining Science and Technology 2024年第2期34卷 211-225页

作者： Xingsen Guo Ning Fan Defeng Zheng Cuiwei Fu Hao Wu yanjun zhang Xiaolong Song Tingkai Nian State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Department of Civil Environmentaland Geomatic EngineeringUniversity College LondonLondon WC1E 6BTUnited Kingdom Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Civil Engineering and Architecture Wenzhou UniversityWenzhou 325035China Key Laboratory of Engineering and Technology for Soft Soil Foundation and Tideland Reclamation of Zhejiang Province Wenzhou 325035China Zhejiang International Science and Technology Cooperation Base of Ultra-soft Soil Engineering and Smart Monitoring Wenzhou 325035China School of Geography Liaoning Normal UniversityDalian 116029China China Railway First Survey and Design Institute Group Co. Ltd.Xi’an 710043China Department of Geotechnical Engineering Nanjing Hydraulic Research InstituteNanjing 210024China Wuhan Center China Geological Survey(Central South China Innovation Center for Geosciences)Wuhan 430205China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China

Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental protection.However,the placement of these pipelines on the seabed surface exposes them to potential risks arising from the complex deep-sea hydrodynamic and geological environment,particularly submarine slides.Historical incidents have highlighted the substantial damage to pipelines due to slides.Specifically,deep-sea fluidized slides(in a debris/mud flow or turbidity current physical state),characterized by high speed,pose a significant threat.Accurately assessing the impact forces exerted on pipelines by fluidized submarine slides is crucial for ensuring pipeline safety.This study aimed to provide a comprehensive overview of recent advancements in understanding pipeline impact forces caused by fluidized deep-sea slides,thereby identifying key factors and corresponding mechanisms that influence pipeline impact forces.These factors include the velocity,density,and shear behavior of deep-sea fluidized slides,as well as the geometry,stiffness,self-weight,and mechanical model of pipelines.Additionally,the interface contact conditions and spatial relations were examined within the context of deep-sea slides and their interactions with pipelines.Building upon a thorough review of these achievements,future directions were proposed for assessing and characterizing the key factors affecting slide impact loading on pipelines.A comprehensive understanding of these results is essential for the sustainable development of deep-sea pipeline projects associated with seabed resource development and the implementation of disaster prevention measures.

关键词： Deep-sea fluidized slides Pipes Impact forces Shear behavior of slides Interface contact conditions Spatial relation

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Higher-order properties and extensions for indirect MRAC and APPC of linear systems

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Science China(Information Sciences) 2024年第4期67卷 218-238页

作者： yanjun zhang Zhipeng zhang Jian SUN Lei WANG Kangkang zhang National Key Lab of Autonomous Intelligent Unmanned Systems Beijing Institute of Technology School of Automation Beijing Institute of Technology 3. Beijing Institute of Technology Chongqing Innovation Center College of Control Science and Engineering Zhejiang University Department of Electrical and Electronic Engineering Imperial College London KIOS Research and Innovation Center of Excellence University of Cyprus

Recently, a reference derived some new higher-order output tracking properties for direct model reference adaptive control(MRAC) of linear time-invariant(LTI) systems: limt→∞ e~((i))(t) = 0, i = 1,..., n~*-1, where n~* and e~((i))(t) denote the relative degree of the system and the i-th derivative of the output tracking error, respectively. However, a naturally arising question involves whether indirect adaptive control(including indirect MRAC and indirect adaptive pole placement control) of LTI systems still has higher-order tracking properties. Such properties have not been reported in the literature. Therefore, this paper provides an affirmative answer to this question. Such higher-order tracking properties are new discoveries since they hold without any additional design conditions and, in particular, without the persistent excitation condition. Given the higher-order properties, a new adaptive control system is developed with stronger tracking features.(1) It can track a reference signal with any order derivatives being unknown.(2) It has higher-order exponential or practical output tracking properties.(3) Finally, it is different from the usual MRAC system, whose reference signal’s derivatives up to the n~* order are assumed to be known. Finally, two simulation examples are provided to verify the theoretical results obtained in this paper.

关键词： higher-order tracking indirect adaptive control model reference adaptive control adaptive pole placement control

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Three-Rigid-Body-Particle Modeling and Optimization of Trajectory and Posture for Alpine Skiing

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Journal of Systems Science & Complexity 2024年第2期37卷 581-608页

作者： zhang Yijia FEI Qing YAO Xiaolan SUN Jian zhang yanjun CHEN Zhen School of Automation Beijing Institute of TechnologyBeijing 100081China

This paper presents a new study on modeling and optimization of trajectory and posture for the super-giant(SG)slalom of alpine skiing.It is the first time that a Three-Rigid-Body-Particle model based on rigorous derivations and stability analysis is established to represent skiers trajectory and posture characteristics,as it is more accurate than the single-rigid-body model which is commonly used in existing studies.In addition,the Radau pseudospectral method is applied to solve the trajectory and posture optimization problem in order to obtain better skiing trajectory,skiing posture,and some key kinematic parameters of skiers.Moreover,this paper analyzes the effects of different body types,minimum turning radii,and flexor and extensor strength of knees and hip joint on skiing performance.Finally,based on the findings of the study,some advice about how to improve the performance of the SG slalom in view of science and technology is given to skiers and coaches for reference.

关键词： Alpine skiing modeling posture optimization Three-Rigid-Body-Particle model trajectory optimization

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Adaptive PI Control Based Stability Margin Configuration of Aircraft Control Systems with Unknown System Parameters and Time Delay

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Journal of Systems Science & Complexity 2024年第4期37卷 1507-1525页

作者： zhang Zhibing ZHOU Dapeng WANG Yeguang GAO Wanxin zhang yanjun AVIC Shenyang Aircraft Design and Research Institute School of Automation Beijing Institute of Technology State Key Lab of Autonomous Intelligent Unmanned Systems Beijing Institute of Technology

The stability margin is a vital indicator for assessing the safety level of aircraft control systems. It should maintain sufficient stability margin to ensure safety during flight, especially in the process of large maneuver operations. The stability margin is generally quantified by the Bode diagram,which strictly depends on the system parameters and the open-loop transfer function. However, due to the uncertain flight environments, transmission delays of sensors and mode switchings, etc., there exist large parameter and structure uncertainties in the aircraft control systems, which make it difficult to precisely configure the stability margin to the desired value by the usual control methods. To address this problem, an indirect adaptive control strategy is proposed in this paper, where an adaptive PI control law with the capability of self-configuration of stability margin is developed. The developed control law not only achieves stable time-varying command tracking in the time domain, but also is able to automatically configure the phase margin and gain margin in the frequency domain. Finally,the simulation of the one-degree-of-freedom roll rate control model of the air vehicle verifies the validity of the proposed control method.

关键词： Adaptive control aircraft control parameter uncertainty stability margin configuration

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Three-Stages Hyperspectral Image Compression Sensing with Band Selection

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Computer Modeling in Engineering & Sciences 2023年第1期131卷 293-316页

作者： Jingbo zhang yanjun zhang Xingjuan Cai Liping Xie Taiyuan University of Science and Technology Taiyuan030024China

Compressed sensing(CS),as an efficient data transmission method,has achieved great success in the field of data transmission such as image,video and text.It can robustly recover signals from fewer Measurements,effectively alleviating the bandwidth pressure during data transmission.However,CS has many shortcomings in the transmission of hyperspectral image(HSI)data.This work aims to consider the application of CS in the transmission of hyperspectral image(HSI)data,and provides a feasible research scheme for CS of HSI data.HSI has rich spectral information and spatial information in bands,which can reflect the physical properties of the target.Most of the hyperspectral image compressed sensing(HSICS)algorithms cannot effectively use the inter-band information of HSI,resulting in poor reconstruction effects.In this paper,A three-stage hyperspectral image compression sensing algorithm(Three-stages HSICS)is proposed to obtain intra-band and inter-band characteristics of HSI,which can improve the reconstruction accuracy of HSI.Here,we establish a multi-objective band selection(Mop-BS)model,amulti-hypothesis prediction(MHP)model and a residual sparse(ReWSR)model for HSI,and use a staged reconstruction method to restore the compressed HSI.The simulation results show that the three-stage HSICS successfully improves the reconstruction accuracy of HSICS,and it performs best among all comparison algorithms.

关键词： Combinatorial optimization band selection hyperspectral image compressed sensing

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Taxonomy of Epimedium(Berberidaceae)with special reference to Chinese species

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Chinese Herbal Medicines 2022年第1期14卷 20-35页

作者： yanjun zhang Jianqiang Li Ying Wang Qiong Liang Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China Provincial Key Laboratory of Digital Botanical Garden and Public Science South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China

Epimedii Herba is a commonly used traditional Chinese herbal medicine.Five Epimedium species are included in Chinese Pharmacopoeia and most species of Epimedium are used as Epimedii Herba in practical application.However,as the largest herbaceous genus of the Berberidaceae,Epimedium has many taxonomic controversies which hinder the effective use of Epimedii Herba.This paper reviewed the taxonomic research related to Epimedium,including taxonomic history,taxonomic values of morphological characters,species and distribution,infra-genera taxonomic system and the taxonomic research of Chinese Epimedium.For instance,we recognized Epimedium wushanense and clarified that the species,as described in Flora Reipublicae Popularis Sinicae and Flora of China,actually includes four Epimedium species similar in leaflet shape.In general,it was recognized here that Epimedium comprises 62 species,of which 52 species are distributed in China.For Chinese Epimedium species with the most taxonomic problems,the taxonomic research on the taxa was reviewed and the newest species key was proposed along with proposals for those taxonomic problems needing further resolution.This review is of great implication for the identification,exploration and utilization of Epimedii Herba.

关键词： Chinese taxon Epimedium L. Taxonomy Review

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LSTM-Based Adaptive Modulation and Coding for Satellite-to-Ground Communications

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Journal of Beijing Institute of Technology 2022年第5期31卷 473-482页

作者： Shiqi zhang Guoxin Yu Shanping Yu yanjun zhang Yu zhang School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China. School of Cyberspace Science and Technology Beijing Institute of TechnologyBeijing 100081China

Satellite communication develops rapidly due to its global coverage and is unrestricted to the ground environment. However, compared with the traditional ground TCP/IP network, a satellite-to-ground link has a more extensive round trip time(RTT) and a higher packet loss rate,which takes more time in error recovery and wastes precious channel resources. Forward error correction(FEC) is a coding method that can alleviate bit error and packet loss, but how to achieve high throughput in the dynamic network environment is still a significant challenge. Inspired by the deep learning technique, this paper proposes a signal-to-noise ratio(SNR) based adaptive coding modulation method. This method can maximize channel utilization while ensuring communication quality and is suitable for satellite-to-ground communication scenarios where the channel state changes rapidly. We predict the SNR using the long short-term memory(LSTM) network that considers the past channel status and real-time global weather. Finally, we use the optimal matching rate(OMR) to evaluate the pros and cons of each method quantitatively. Extensive simulation results demonstrate that our proposed LSTM-based method outperforms the state-of-the-art prediction algorithms significantly in mean absolute error(MAE). Moreover, it leads to the least spectrum waste.

关键词： satellite communication long short-term memory forward error correction rain loss adaptive modulation and coding

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A High-Quality Adaptive Video Reconstruction Optimization Method Based on Compressed Sensing

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Computer Modeling in Engineering & Sciences 2023年第10期137卷 363-383页

作者： yanjun zhang Yongqiang He Jingbo zhang Yaru Zhao Zhihua Cui Wensheng zhang School of Computer Science and Technology Taiyuan University of Science and TechnologyTaiyuan030024China Department of Big Data and Intelligent Engineering Shanxi Institute of TechnologyYangquan045000China School of Computer Science Beijing University of TechnologyBeijing100124China The Institute of Automation Chinese Academy of Sciences(CAS)Beijing100049China

The video compression sensing method based onmulti hypothesis has attracted extensive attention in the research of video codec with limited resources.However,the formation of high-quality prediction blocks in the multi hypothesis prediction stage is a challenging task.To resolve this problem,this paper constructs a novel compressed sensing-based high-quality adaptive video reconstruction optimizationmethod.Itmainly includes the optimization of prediction blocks(OPBS),the selection of searchwindows and the use of neighborhood information.Specifically,the OPBS consists of two parts:the selection of blocks and the optimization of prediction blocks.We combine the high-quality optimization reconstruction of foreground block with the residual reconstruction of the background block to improve the overall reconstruction effect of the video sequence.In addition,most of the existing methods based on predictive residual reconstruction ignore the impact of search windows and reference frames on performance.Therefore,Block-level search window(BSW)is constructed to cover the position of the optimal hypothesis block as much as possible.To maximize the availability of reference frames,Nearby reference frame information(NRFI)is designed to reconstruct the current block.The proposed method effectively suppresses the influence of the fluctuation of the prediction block on reconstruction and improves the reconstruction performance.Experimental results showthat the proposed compressed sensing-based high-quality adaptive video reconstruction optimization method significantly improves the reconstruction performance in both objective and supervisor quality.

关键词： Compressed sensing OPBS block-level search window nearby reference frame information evolutionary algorithm

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Peripheral origin exosomal micro RNAs aggravate glymphatic system dysfunction in diabetic cognitive impairment

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药学学报:英文版 2023年第7期13卷 2817-2825页

作者： Lin zhang Dongna Li Pengrong Yi Jiangwei Shi Mengqing Guo Qingsheng Yin Dingbin Liu Pengwei Zhuang yanjun zhang State Key Laboratory of Component-based Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Haihe Laboratory of Modern Chinese Medicine Tianjin 301617China First Teaching Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300193China National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300193China State Key Laboratory of Medicinal Chemical Biology Research Center for Analytical Sciencesand Tianjin Key Laboratory of Molecular Recognition and BiosensingCollege of ChemistryNankai UniversityTianjin 300071China

Cognitive dysfunction is one of the common central nervous systems(CNS)complications of diabetes mellitus,which seriously affects the quality of life of patients and results in a huge economic burden.The glymphatic system dysfunction mediated by aquaporin-4(AQP4)loss or redistribution in perivascular astrocyte endfeet plays a crucial role in diabetes-induced cognitive impairment(DCI).However,the mechanism of AQP4 loss or redistribution in the diabetic states remains unclear.Accumulating evidence suggests that peripheral insulin resistance target tissues and CNS communication affect brain homeostasis and that exosomal miRNAs are key mediators.Glucose and lipid metabolism disorder is an important pathological feature of diabetes mellitus,and skeletal muscle,liver and adipose tissue are the key target insulin resistance organs.In this review,the changes in exosomal miRNAs induced by peripheral metabolism disorders in diabetes mellitus were systematically reviewed.We focused on exosomal miRNAs that could induce low AQP4 expression and redistribution in perivascular astrocyte endfeet,which could provide an interorgan communication pathway to illustrate the pathogenesis of DCI.Furthermore,the mechanisms of exosome secretion from peripheral insulin resistance target tissue and absorption to the CNS were summarized,which will be beneficial for proposing novel and feasible strategies to optimize DCI prevention and/or treatment in diabetic patients.

关键词： Diabetic cognitive impairment AQP4 Peripheral-central communication Exosomal miRNAs Central nervous system Glymphatic system Diabetes mellitus Astrocyte

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Off-grid DOA estimation via a deep learning framework

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Science China(Information Sciences) 2023年第12期66卷 222-237页

作者： Yan HUANG yanjun zhang Jun TAO Cai WEN Guisheng LIAO Wei HONG State Key Lab of Millimeter Waves Southeast University Key Laboratory of Underwater Acoustic Signal Processing of Ministry of Education Southeast University School of Information Science and Technology Northwest University National Key Lab of Radar Signal Processing Xidian University

Direction-of-arrival(DOA) estimation problem is one of the most important tasks for array signal processing. Conventional methods are limited by either the computational complexity or the resolution. In this paper, a novel deep learning(DL) framework for super-resolution DOA estimation is developed, where the grid mismatch problem is fully considered into the DL DOA estimation and the offset between the real DOA and the discrete sampling grid is thereby trained as a part of the network output. Specifically, we first model the DOA estimation problem as a multi-classification task and obtain the on-grid estimation result with a resolution of 1° as the first output. Then we designed another regression module to estimate the offset between target angles and the corresponding grids. By combining both on-grid and offset estimation results, the accurate off-grid estimation is achieved. In addition, the method of fusing low-level features and high-level features by skip connection is adopted between the on-grid estimation module and the offset estimation module. The high-level features in the first part of the network are combined with the original input to improve the training speed and the estimation accuracy. Herein, our training dataset contains a large number of off-grid signal data, which is close to the practical application. Also, the utilization of the off-grid part information improves DOA estimation performance compared to existing DL-based methods,achieving more accurate DOA estimations. Numerous simulation results have demonstrated the superiority of the proposed method in DOA estimation precision, and a good performance advantage maintains even when using a limited number of snapshots. Further, we test the proposed method on the real millimeter-wave radar system, and it outperforms the other state-of-the-art methods, especially for two adjacent targets in the same range and Doppler bin.

关键词： direction-of-arrival (DOA) estimation deep learning (DL) off-grid array signal processing

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