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Hybrid partition-and network-level scheduling design for distributed integrated modular avionics systems

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Chinese Journal of Aeronautics 2020年第1期33卷 308-323页

作者： xuan zhou Huagang XIONG Feng HE School of Electronic and Information Engineering Beihang UniversityBeijing 100191China

Distributed Integrated Modular Avionics(DIMA)develops from Integrated Modular Avionics(IMA)and realizes distributed integration of multiple sub-function *** network provides effective support for time synchronization and information coordination in DIMA ***,inconsistency between processing resources and communication network destroys the time determinism benefiting from partitions and time-triggered *** ensure such time determinism and achieve guaranteed real-time performance,system design should collectively provide a global communication scheme for messages in network domain and a corresponding execution scheme for partitions in processing *** paper firstly establishes a general DIMA model which coordinates partitioned processing and time-triggered communication,and then proposes a hybrid scheduling algorithm using Mixed Integer Programming to produce feasible system ***,incrementally integrating new functions causes upgrades or reconfigurations of DIMA systems and will generate integration *** control such cost,this paper further develops an optimization algorithm based on Maximum Satisfiability Problem and guarantees that the scheduling design for upgraded DIMA systems inherit their original schemes as much as ***,two typical cases,including a simple fully connected DIMA system case and an industrial DIMA system case,are constructed to illustrate our DIMA model and validate the effectiveness of our hybrid scheduling algorithms.

关键词： Distributed integrated modular avionics End-to-end delay Incremental integration cost Maximum satisfiability problem Mixed integer programming Scheduling algorithms

Comparison of the topologies for a hybrid energy-storage system of electric vehicles via a novel optimization method

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Science China(Technological Sciences) 2015年第7期58卷 1173-1185页

作者： ZHANG Shuo XIONG Rui zhou xuan National Engineering Laboratory for Electric Vehicles School of Mechanical EngineeringBeijing Institute of Technology Collaborative Innovation Center of Electric Vehicles in Beijing Beijing Institute of Technology Electrical and Computer Engineering Department Kettering University

The combination of batteries and ultracapacitors has become an effective solution to satisfy the requirements of high power density and high energy density for the energy-storage system of electric *** aspects of such combination efforts were considered for evaluating the four types of hybrid energy-storage system(HESS)***,a novel optimization framework was proposed and implemented to optimize the voltage level of a battery pack and an ultracapacitor pack for the four types of HESS *** the optimization process,the dynamic programming(DP)algorithm was iteratively applied to determine the optimal control *** simulation results with DP were used to evaluate the energy efficiency of different HESS topologies at different voltage ***,the optimized voltage level of the battery and ultracapacitor in each topology indicates that a higher voltage level usually results in a better system *** simulation results also illustrate that the optimized rated voltage level of the battery pack is approximately 499.5 V,while for the ultracapacitor pack,the optimized voltage level is at its maximum allowed *** that the constraint of the battery voltage is initialized at200–600 ***,the control rules for different HESS topologies were obtained through the systematic analysis of the simulation *** addition,advantages and disadvantages of the four topologies were summarized through evaluation of the efficiency and operating currents of the batteries and the ultracapacitor.

关键词： electric vehicles lithium-ion battery ultracapacitor hybrid energy-storage system topology dynamic programming

From blocker to booster:Harnessing garnet surface chemistry for advanced solid-state electrolytes

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Nano Research 2025年第1期18卷 323-331页

作者： Jun Cheng xuan zhou Hongqiang Zhang Zhen Zeng Yuanyuan Li Yulong Zhu Yingsheng Liao Lijie Ci Deping Li State Key Laboratory of Precision Welding and Joining of Materials and Structures School of Materials Science and EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055China

Garnet electrolytes with high ionic conductivity and electrochemical stability are widely used as fillers to fabricate composite solid electrolytes(CPEs)within polymer ***,the performance of CPEs is significantly influenced by the surface characteristics of the garnet ***,the impact of garnet surface characteristics on CPEs was systematically investigated and a conversion from a typically unstable and Lewis basic surface to a more stable Lewis acidic surface was realized,which is shown to be more conductive to the improved performance of *** simultaneously removing the Li_(2)CO_(3)layer and applying a Li-Al-O coating,the influence of surface characteristics on CPEs was *** Lewis acid Li-Al-O surface coating not only promotes lithium salt dissociation,improving the ionic conductivity and ionic transfer number,but also prevents the reformation of the passive Lewis basic Li_(2)CO_(3)*** to garnet with a Lewis basic Li_(2)CO_(3)surface,the garnet modified with a Lewis acid Li-Al-O coating enhances CPEs,which exhibit an improved critical current density of 1.0 mA·cm^(-2)and highly stable lithium symmetric cell cycling for 400 h at 0.2 mA·cm^(-2).This research highlights the importance of surface chemistry in the design of high-performance solid-state batteries and presents a strategic modification approach for garnetbased CPEs.

关键词： garnet electrolyte composite solid electrolyte surface chemistry all-solid-state batteries

RS-store:RDMA-enabled skiplist-based key-value store for efficient range query

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Frontiers of Computer Science 2021年第6期15卷 133-146页

作者： Chenchen HUANG Huiqi HU Xuecheng Qi xuan zhou Aoying zhou School of Data Science and Engineering East China Normal UniversityShanghai 200062China

Many key-value stores use RDMA to optimize the messaging and data transmission between application layer and the storage layer,most of which only provide point-wise ***-based store can support both point operations and range queries,but its CPU-intensive access operations combined with the high-speed network will easily lead to the storage layer reaches CPU *** common solution to this problem is offloading some operations into the application layer and using RDMA bypassing CPU to directly perform remote access,but this method is only used in the hash tablebased *** this paper,we present RS-store,a skiplist-based key-value store with RDMA,which can overcome the CPU handle of the storage layer by enabling two access modes:local access and remote *** RS-store,we redesign a novel data structure R-skiplist to save the communication cost in remote access,and implement a latch-free concurrency control mechanism to ensure all the concurrency during two access ***-store also supports client-active range query which can reduce the storage layer’s CPU *** last,we evaluate RS-store on an RDMA-capable *** results show that RS-store achieves up to 2x improvements over RDMA-enabled RocksDB on the throughput and application’s scalability.

关键词： key-value store skiplist RDMA

Scalable and adaptive log manager in distributed systems

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Frontiers of Computer Science 2023年第2期17卷 45-62页

作者： Huan zhou Weining QIAN xuan zhou Qiwen DONG Aoying zhou Wenrong TAN The Key Laboratory for Computer Systems of State Ethnic Affairs Commission Southwest Minzu UniversityChengdu 610041China School of Data Science and Engineering East China Normal UniversityShanghai 200062China

On-line transaction processing(OLTP)systems rely on transaction logging and quorum-based consensus protocol to guarantee durability,high availability and strong *** makes the log manager a key component of distributed database management systems(DDBMSs).The leader of DDBMSs commonly adopts a centralized logging method to writing log entries into a stable storage device and uses a constant log replication strategy to periodically synchronize its state to *** the advent of new hardware and high parallelism of transaction processing,the traditional centralized design of logging limits scalability,and the constant trigger condition of replication can not always maintain optimal performance under dynamic *** this paper,we propose a new log manager named Salmo with scalable logging and adaptive replication for distributed database *** scalable logging eliminates centralized contention by utilizing a highly concurrent data structure and speedy log hole *** kernel of adaptive replication is an adaptive log shipping method,which dynamically adjusts the number of log entries transmitted between leader and followers based on the real-time *** implemented and evaluated Salmo in the open-sourced transaction processing systems Cedar and *** results show that Salmo scales well by increasing the number of working threads,improves peak throughput by 1.56×and reduces latency by more than 4×over log replication of Raft,and maintains efficient and stable performance under dynamic workloads all the time.

关键词： distributed database systems transaction log-ging log replication scalable adaptive

Unlocking plant metabolic diversity: A (pan)- genomic view

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Plant Communications 2022年第2期3卷 112-120页

作者： xuan zhou Zhenhua Liu Joint Center for Single Cell Biology School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China Shanghai Collaborative Innovation Center of Agri-Seeds School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China

Plants produce a remarkable diversity of structurally and functionally diverse natural chemicals that serve as adaptive compounds throughout their life ***,unlocking this metabolic diversity is significantly impeded by the size,complexity,and abundant repetitive elements of typical plant *** genome sequencing becomes routine,we anticipate that links between metabolic diversity and genetic variation will be *** addition,an ever-increasing number of plant genomes have revealed that biosynthetic gene clusters are not only a hallmark of microbes and fungi;gene clusters for various classes of compounds have also been found in plants,and many are associated with important agronomic *** present recent examples of plant metabolic diversification that have been discovered through the exploration and exploitation of various genomic and pan-genomic *** also draw attention to the fundamental genomic and pan-genomic basis of plant chemodiversity and discuss challenges and future perspectives for investigating metabolic diversity in the coming pan-genomics era.

关键词： metabolic diversity gene and genome duplication biosynthetic gene clusters genomic structural variations pan-genomics

Fine-Grained Action Recognition Based on Temporal Pyramid Excitation Network

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Intelligent Automation & Soft Computing 2023年第8期37卷 2103-2116页

作者： xuan zhou Jianping Yi School of Mechanical&Electrical Engineering Xi’an Traffic Engineering InstituteXi’an710300China School of Electronics and Information Xi’an Polytechnic UniversityXi’an710048China

Mining more discriminative temporal features to enrich temporal context representation is considered the key to fine-grained action *** action recognition methods utilize a fixed spatiotemporal window to learn local video ***,these methods failed to capture complex motion patterns due to their limited receptive *** solve the above problems,this paper proposes a lightweight Temporal Pyramid Excitation(TPE)module to capture the short,medium,and long-term temporal *** this method,Temporal Pyramid(TP)module can effectively expand the temporal receptive field of the network by using the multi-temporal kernel decomposition without significantly increasing the computational *** addition,the Multi Excitation module can emphasize temporal importance to enhance the temporal feature representation *** can be integrated into ResNet50,and building a compact video learning *** validation experiments on several challenging benchmark(Something-Something V1,Something-Something V2,UCF-101,and HMDB51)datasets demonstrate that our method achieves a preferable balance between computation and accuracy.

关键词： Fine-grained action recognition temporal pyramid excitation module temporal receptive multi-excitation module

Abnormal Behavior Detection and Recognition Method Based on Improved ResNet Model

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Computers, Materials & Continua 2020年第12期65卷 2153-2167页

作者： Huifang Qian Mengmeng Zheng xuan zhou School of Electronics and Information Xi’an Polytechnic UniversityXi’an710048China

The core technology in an intelligent video surveillance system is that detecting and recognizing abnormal behaviors timely and *** key breakthrough point in recognizing abnormal behaviors is how to obtain the effective features of the picture,so as to solve the problem of recognizing *** response to this difficulty,this paper introduces an adjustable jump link coefficients model based on the residual *** effective coefficients for each layer of the network can be set after using this model to further improving the recognition accuracy of abnormal behavior.A convolution kernel of 1×1 size is added to reduce the number of parameters for the purpose of improving the speed of the model in this *** order to reduce the noise of the data edge,and at the same time,improve the accuracy of the data and speed up the training,a BN(Batch Normalization)layer is added before the activation function in this *** paper trains this network model on the public ImageNet dataset,and then uses the transfer learning method to recognize these abnormal behaviors of human in the UTI behavior dataset processed by the YOLO_v3 target detection *** the same experimental conditions,compared with the original ResNet-50 model,the improved model in this paper has a 2.8%higher accuracy in recognition of abnormal behaviors on the public UTI dataset.

关键词： ResNet abnormal behavior recognition YOLO_v3 adjustable jump link coefficients model standard normal distribution

Electrochemical micromachining of microgroove arrays on phosphor bronze surface for improving the tribological performance

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Chinese Journal of Aeronautics 2018年第7期31卷 1609-1618页

作者： xuan zhou Ningsong QU Zhibao HOU Gai ZHAO College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing 210016 China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016 China

A high friction coefficient and a low wear rate of contacted surfaces are essential elements to friction pairs between the stator and the rotor in ultrasonic motors. It has been shown that surface textures have a significant effect on improving the tribological performance of friction *** this paper, microgroove arrays are introduced to the stator surface for improving the tribological performance of friction pairs between the stator and the rotor in ultrasonic motors. Microgrooves were fabricated on a phosphor bronze surface by through-mask electrochemical micromachining（TMEMM）. Parameters, namely, the electrolyte inlet pressure, applied voltage, pulse duty cycle,and frequency, were varied to investigate their influences on the dimensions and morphology of the microgrooves. Results showed that the width and depth of the microgrooves were strongly affected by the applied voltage and frequency, while the morphology of the microgrooves was dependent on the electrolyte inlet pressure and the pulse duty cycle. Compared with a smooth surface, the friction coefficient increased from 0.245 to 0.334 and less abrasion was obtained when a surface was textured with microgrooves of which the width and depth were 185.6 and 57.6 lm,respectively. Microgroove arrays might play an important role in enhancing the performance of ultrasonic motors.

关键词： Friction coefficient Microgrooves Through-mask electrochemical micromachining Ultrasonic motors Wear