AbstractThe aerodynamic environment in low-altitude regions is characterised by complex flow field structures, diverse disturbance sources, and significant coupling effects. These factors have a significant impact on the aerodynamic performance and flight safety of UAV (unmanned aerial vehicle), making them a key focus of research in the field of low-altitude UAV aerodynamics. Three typical scenarios were systematically reviewed: complex low-altitude wind fields, spatially constrained environments, and multi-UAV environments. The fundamental characteristics and modelling approaches of complex low-altitude wind fields were systematically outlined, and their effects on UAV and key research methodologies were summarised. Spatially constrained environments were categorised based on disturbance mechanisms and constraint types, and a comprehensive summary of the aerodynamic impacts on UAV within such environments was provided. The aerodynamic characteristics of UAV in multi-UAV environments were summarised, and the aerodynamic coupling mechanisms and research methodologies for cooperative and non-formation flight scenarios were outlined. Building upon this foundation, the core issues and key challenges currently facing aerodynamic research on UAV in low-altitude environments were further refined, and future research priorities in this field were outlined.

AbstractTo address the critical need for autonomous navigation of low-altitude UAVs (unmanned aerial vehicles) in GNSS (global navigation satellite system)-denied environments, a comprehensive survey was presented on absolute visual localization techniques based on a "retrieval-matching-pose estimation" framework. Key challenges inherent to low-altitude UAV observations—including significant imaging disparities, scale variations, and object occlusions—were analyzed, thereby elucidating the advantages of this hierarchical framework for large-scale, long-endurance localization tasks. Subsequently, the technological evolution and state-of-the-art advancements across three core components (cross-view image retrieval, pixel-level feature matching, and UAV pose estimation) were systematically reviewed, tracing the progression from traditional handcrafted features to deep learning paradigms. Finally, considering the deployment requirements of onboard edge computing platforms, the limitations of existing technologies were discussed, and promising future research directions were outlined. This survey is intended to serve as a valuable reference for both research and practical applications in absolute visual localization for low-altitude UAVs.

AbstractRecent advances in information technology and new energy systems have introduced increasingly stringent requirements for regulating energy transport within materials. Conventional material-design paradigms are limited by inherent trade-offs among optical, thermal, and electrical transport properties, creating an urgent need for a new paradigm to fundamentally decouple and reconstruct material functionalities. Recent progress on nanoporous aerogels as an enabling platform was systematically summarized, emphasizing how hierarchical structural design and cross-scale assembly of building units allow precise control of diverse energy-carrier transport. Based on this theoretical framework, advanced applications in photo thermal electrical energy conversion were highlighted, with particular emphasis on research progress and performance optimization pathways of aerogels for photothermal, photoelectric, thermoelectric, and integrated photo thermal electric systems. Finally, future research directions including AI-driven inverse design and synergistic regulation of multiple energy carriers were outlooked, providing new perspectives for the on-demand development of next-generation high-performance photo-thermal-electrical conversion materials.

AbstractWith the increasing number of space activities, HVI (hypervelocity impacts) caused by space debris and micrometeoroids have become a major threat to the safety of spacecraft in orbit. Such collisions not only result in mechanical damage but also generate plasma, whose electromagnetic effects pose severe risks to highly integrated spacecraft electronic systems. A systematic review of plasma physical effects induced by hypervelocity impacts was provided.The review covered the mechanisms of plasma generation, kinetic characteristics, electromagnetic radiation, and induced discharge, encompassing both theoretical and experimental progress. Special emphasis was placed on the introduction of condensed-phase products (dust grains) in hypervelocity impacts and the resulting dusty plasma effects. This review aims to offer researchers in the field a comprehensive literature summary and to highlight key scientific questions and future research directions. Ultimately, it seeks to provide theoretical support for enhancing the survivability of spacecraft in orbit and for developing next-generation electromagnetic protection technologies.

AbstractDuring the high-speed flight of aircraft, raindrop impact erosion causes significant damage to surface materials, thereby seriously affecting flight performance and structural safety. This paper is aimed to systematically review the mechanical mechanism, key influencing factors, and progress in corresponding protection technologies of high-speed raindrop impact erosion. In terms of experiments, current studies mainly rely on devices such as wind tunnels, rocket sleds, and rotating arms to construct simulated environments of real rain fields. Meanwhile, high-speed photography is used to record the dynamic erosion process, and laser velocimetry is employed to obtain raindrop impact velocity, thus achieving multi-dimensional observation of erosion behavior. In terms of numerical simulation, it was focused on introducing mainstream simulation techniques such as the finite element method and the smoothed particle hydrodynamics method. Additionally, an overview was provided of existing research methods and outcomes, which primarily involve establishing liquid-solid coupling models to analyze the propagation patterns of stress waves and the dynamic response characteristics of materials during impact processes. The research results show that raindrop impact velocity, impact angle, and mechanical properties of materials are the key factors affecting the erosion rate. Based on the actual flight envelope parameters of aircraft, targeted optimization design of rain erosion resistance performance can be carried out, which can provide a theoretical basis and technical support for improving the service safety of aircraft in harsh meteorological environments.

AbstractCurrently, countries around the world are generally unable to defend effectively against high-speed vehicles, and related basic research is still in its infancy. Accelerating the development of high-speed target defense technology is crucial for maintaining aerospace security. Given the problems present in the near-space defense confrontation under this background, such as a narrow defensive posture, significant speed disadvantages, and limited single-missile defense capability, this paper reviews the current development status of the defense guidance law for high-speed near-space vehicles. It analyzes the deficiencies of the existing guidance law research from perspectives such as complex offensive and defensivescenarios,cooperative guidance mechanisms, and real environmentconstraints. It also foresees the key development directions of future defense guidance laws for high-speed vehicles, aiming to offer references for the construction of future defense systems for high-speed vehicles and the frontier basic research in the field of precision guidance.

AbstractIt was presented that a review of model predictive control and its applications in aircraft systems. Starting from representative mission scenarios and key technical challenges, it clarifies the design requirements of aircraft control systems. In response to the design needs of different classes of vehicles, the review surveys and synthesizes a coherent framework for model predictive control. It traces the origins and development of model predictive control and summarizes its theoretical foundations, with particular attention to robust model predictive control, Lyapunov model predictive control, switched model predictive control, and explicit model predictive control, thereby delineating the principal advances reported in recent years. Building on this framework, the paper examines applications of model predictive control to quadrotors, helicopters, fixed-wing aircraft, and high-speed aircraft. Finally, it outlines future research directions for model predictive control in aerospace control and offers concluding remarks.

AbstractThe aviation and aerospace transition zone, spanning altitudes between 50~250 km, constitutes a strategic arena for hypersonic weapon penetration and electronic warfare operations, serving as a critical battlefield that significantly impacts operational effectiveness. AI (artificial intelligence) is profoundly empowering the regions information warfare systems, driving their evolution toward dynamic and intelligent capabilities. Key AI technologies and applications across the entire “perception-fusion-prediction-countermeasure” chain are systematically reviewed: relying on deep learning for efficient inversion of environmental parameters; utilizing intelligent fusion to construct digital twins of battlefield environments; enhancing forecast accuracy through physical information; and developing autonomous learning and game-theoretic decision-making capabilities to support precise cognition and counter-interference.The core challenges facing AI-enabled information warfare include environmental perception uncertainty, weak model interpretability, difficulties in cross-domain transfer, and restricted data acquisition. Finally, the outlook for future development is presented, emphasizing that AI is evolving from a technical tool into a core driving force.

AbstractA thermal concentrator is a thermal functional device based on transformation thermotics, effective-medium theory, and scattering-cancellation principles. By tailoring the spatial distribution of thermal conductivity or geometric configurations, it efficiently concentrates large-scale heat flux into localized regions, enabling precise control of both steady-state and transient heat transport. With advances in materials science and manufacturing technologies, research on the thermal concentrator is moving from theoretical models toward engineering implementation, and it shows application potential in microelectronic cooling, thermoelectric energy harvesting, energy heating, and thermal therapy. The physical mechanisms, structural designs, and implementation pathways of the thermal concentrator were systematically reviewed, summarized its development and representative works, compared the applicability and performance characteristics of different theoretical frameworks and configurations, and analyzed its technical advantages and engineering feasibility in typical application scenarios. Finally, future trends of the thermal concentrator were discussed, including extensions to complex geometries, multiscale systems, emerging energy platforms, and extreme thermal environments.

AbstractFiber-based supercontinuum offer broad spectral bandwidth, high brightness, and excellent spatial coherence, showing great promise in applications such as electro-optical countermeasures, gas sensing, and optical coherence tomography. To address the diverse performance requirements of supercontinuum imposed by different application scenarios, this paper reviewed recent advances in three key directions of fiber-based supercontinuum: power scaling, long wave extension, and low noise research. The technical approaches tailored to enhance each specific performance metric were summarized, and an outlook on future developments was provided, aiming to serve as a reference for the development and application of high-performance supercontinuum.

AbstractDA (data assimilation) is a crucial technical method for improving the accuracy of atmospheric chemical forecasts by integrating the results of atmospheric chemistry models with multi-source observational data, reducing uncertainties in model input data. Centering on DA techniques for atmospheric chemistry models, the transformation process of initial field assimilation for pollutant gases and aerosols from single state variables to multi-state variables was systematically reviewed. Meanwhile, the important progress of pollutant emission source assimilation inversion using ensemble methods and four-dimensional variational methods was focused on the improvement of emission source accuracy, optimization of spatiotemporal resolution, and enhancement of pollutant concentration prediction performance. With the explosive growth of observational data, a core challenge in the current field lies in fully leveraging high-resolution geospatial and remote sensing data for atmospheric chemical DA. The deep integration of DA with artificial intelligence algorithms represents a key research direction to break through this bottleneck and significantly enhance the accuracy of atmospheric composition analysis and forecasting.

AbstractSwarms of maritime USV(unmanned surface vehicle), as a core technology driving the development of marine intelligence, demonstrate significant application value in military reconnaissance, environmental monitoring, maritime search and rescue, and related fields. However, the inherent characteristics of the marine environment, including highly dynamic conditions, environmental uncertainties, and communication constraints, pose formidable challenges to achieving high-performance swarm control in maritime USV. To address these challenges, recent research advances in this field were systematically reviewed. The characteristics of the marine environment were described, the domestic and international developments in USV were summarized, and the core control requirements and key challenges in complex marine scenarios were analyzed. Furthermore, a comprehensive survey of three representative swarm control methodologies was presented: trajectory-based guidance control, path-based guidance control, and target-based guidance control. Finally, promising research directions and future development trends in maritime USV swarm control are discussed and proposed.

AbstractDue to the limitations of human intelligence and artificial intelligence, developing hybrid augmented intelligence based on human-machine collaboration is one of the main research directions for the new generation of artificial intelligence, and the design of collaborative control algorithms is the core issue in achieving such intelligence. Therefore, a review of the current research status of human-machine collaborative enhanced intelligent control systems was provided in this article. Based on the black box characteristics of human behavior, the human behavior modeling methods of human-in-the-loop control systems were systematically sorted out and the advantages, disadvantages, and applicability of various modeling methods were analyzed. For the implementation of human-machine collaborative augmented intelligent control, the control design methods of machines collaborating with humans under different control theory frameworks were elaborated in detail. The scalability of human-machine collaborative control technology in the field of multi-agent systems and the evaluation methods of hybrid intelligence in the human-machine collaborative control systems were investigated and discussed. In addition, the application scenarios of human-machine collaborative augmented intelligent control methods in medical, industrial, military and other fields were presented. The prospects for human-machine collaborative augmented intelligent control research with the support of new technologies such as large models and embodied learning were presented.

AbstractHigh-performance interconnection networks are among the key factors determining the scalability of supercomputing and intelligent computing systems. Topology serves as the core of scalability-oriented interconnection network design. The design of topology must not only address macro-level requirements from applications and hardware-software systems, but also consider multiple constraints such as router chip port count, number of virtual channels, and packaging density. Significant topological structures from both academia and industry were systematically analyzed and summarized, and a detailed exposition of representative novel topologies was provided. The design challenges of adaptive routing in high-radix networks were examined, the performance and cost of typical topologies were compared, and recommendations for topology selection were discussed. Furthermore, it preliminarily explored future challenges and trends in topology design, including developing cost-effective network topologies tailored to the characteristics of intelligent computing applications, coordinating topology design with building power supply constraints, and integrating and co-designing intra-and inter-supernode network topologies.

AbstractIn the current landscape of large-scale model training, the contradiction between the exponential growth of model parameters and the slow increase in GPU memory capacity has become increasingly prominent. Among memory optimization technologies, recomputation and computational offloading reduce GPU memory overhead by trading time for space. The development trends of recomputation and computational offloading were analyzed in this article. Then, the hardware bandwidth bottlenecks and software ecosystem adaptation challenges faced by memory optimization were analyzed, with a focus on the heterogeneous architecture characteristics of domestic artificial intelligence platforms. It also delved into the memory optimization technologies for large model training on domestic platforms such as MT-3000, with the aim of providing technical references for large model training on domestic platforms.

AbstractIn the era of big data intelligence, knowledge has become the fundamental driving force for technological development. Big data knowledge fusion, which constructs a unified knowledge system by associating multi-source fragmented data, serves as a key support for enhancing knowledge completeness and improving cognitive intelligence. Based on basic paradigms and classic methods, the research status of three key links， knowledge representation learning, knowledge alignment matching, and knowledge conflict resolution， was systematically summarized. Meanwhile, new progress in the context of big data was deeply explored, covering frontier directions such as temporal knowledge fusion, cross-modal knowledge fusion, and large model knowledge fusion. Furthermore, future development trends were prospected, and potential research issues, including the fusion of symbolic and parametric knowledge as well as cross-modal temporal knowledge fusion, were highlighted. Through a panoramic review of basic links and emerging paradigms, important reference and guidance are provided for theoretical expansion and technological evolution in the field of big data knowledge fusion.

AbstractIn the fields of intelligent manufacturing, aerospace, and robotics, control systems often operate under unknown dynamics. This significantly limits the effectiveness of traditional model-based control methods. RL(reinforcement learning), as a data-driven intelligent control approach, enables policy learning and optimization through interaction with the environment, showing great potential for solving optimal control problems in such model-unknown scenarios. This survey focuses on the issue of unknown dynamic models in continuous-time systems and reviews the development of general RL algorithms and their application in model-known scenarios through industrial examples and theoretical analysis methods. It also summarizes representative methods for model-unknown scenarios, such as model-based RL, off-policy integral RL, and Q-learning approaches. The survey introduces Lyapunov-based theoretical analysis tools and important assumptions. It discusses cutting-edge topics such as RL under partial observability using large language models, safe RL, and stability and robustness enhanced RL, while highlighting the challenges faced by existing methods.

AbstractRRAM (resistive random-access memory) has emerged as a promising non-volatile memory technology due to its simple device structure, low power consumption, fast switching speed, and excellent scalability, addressing the data movement bottleneck in traditional compute-memory separation architectures. However, challenges in switching uniformity, cycling endurance, and integration reliability hinder its widespread adoption. This review systematically examined recent advances in RRAM, covering mechanism analysis, performance modulation, process integration technologies, and innovative applications. Starting from resistive switching mechanisms, key approaches based on process optimization and electrical programming strategies were summarized to enhance device uniformity and reliability. At the integration level, recent advances in CMOS（complementary metal-oxide-semiconductor） compatibility at advanced technology nodes and high-density 3D(three-dimensional) integration of RRAM were systematically reviewed. In terms of applications, the development trends of RRAM in high-energy-efficiency in-memory computing, neuromorphic computing, intelligent sensing, and secure chips were analyzed in detail. Towards the future, synergetic cross-scale innovation spanning mechanism, material, and architectural levels were emphasized, supporting the strategic goals of the integrated development of intelligent computing and information technologies.

AbstractDFRC (dual-function radar-communication) is proposed to overcome spectrum conflicts, hardware redundancy, and electromagnetic compatibility bottlenecks inherent in traditional separated architectures through hardware resource sharing and isomorphic signal waveform design, whereby the integrated operational effectiveness and battlefield survivability of platforms are significantly enhanced. The evolution of DFRC technology from its conceptual inception, through architectural advancements, to system implementation was systematically reviewed. The DFRC waveform design methodologies based on mainstream signal schemes were analyzed emphatically, including linear frequency modulation, orthogonal frequency division multiplexing, and orthogonal time frequency space. Furthermore, various sensing-centric waveform design criteria were explored in depth, such as beampattern matching, Cramér-Rao bound minimization, information-theoretical design, and so on. The engineering roadmap from software-defined radio compatibility verification and airborne multimodal waveform fusion to multi-node and multi-domain cooperation was summarized, clearly illustrating the theoretical-to-practical transition of DFRC. Through presenting the complete technical evolution of the DFRC system from the conventional system to multiple-input multiple-output system, and then to the prototype demonstrations, this overview provides systematic theoretical guidance and practical references for future research and development of DFRC systems.

AbstractIn recent years, generative artificial intelligence is progressively introduced into the field of radio spectrum cognition due to its powerful capabilities in data distribution fitting, data generation, and data completion. Compared to conventional approaches relying on physical modeling, mathematical interpolation, and discriminative artificial intelligence techniques, generative AI has significantly enhanced the accuracy of radio spectrum cognition. This paper systematically reviewed the research progress of generative artificial intelligence in radio spectrum cognition, with a focused analysis on the technical principles, application scenarios, and representative works of different generative paradigms. The challenges faced by generative AI in spectrum cognition were further discussed, including scarce training data, limited generalization in unknown scenarios, and insufficient model interpretability. In the future, by cross-modal knowledge fusion, physics-informed embedding, and the establishment of a trustworthy assessment framework, generative artificial intelligence is expected to advance radio spectrum cognition toward high precision, robust generalization, and enhanced interpretability, thereby effectively supporting the efficient utilization of spectrum resources.

AbstractFoundation models have become a focus in radar remote sensing intelligent interpretation due to their provision of universal and generalizable solutions. Significant progress has been achieved in both theoretical and applied aspects of radar remote sensing foundation models, making it imperative to systematically summarize current research advancements. In order to further advance the research on radar remote sensing foundation models, the concept, key technologies, and evaluation methods of foundation models were expounded. Besides, current research progress and application performance were reviewed, with representative approaches and typical instances summarized. In conclusion, discussions and future directions were highlighted from four perspectives: model architecture design, interpretability research, lightweight methods, and security assessment.

AbstractSolid-state pulsed power driver is essential for realizing compact and high-repetition-rate operation of high-power microwave systems. This paper reviewed the domestic and international research status of solid-state pulsed power driver, focusing on the investigation and review of three mainstream modular superimposed technology routes: solid-state Marx pulse generator, solid-state linear transformer driver, and solid-state stacked Blumlein line pulsed power driver. From the perspective of switches, the current technical challenges were mainly concentrated on three aspects: the constraining factors of switch operating characteristics and frequency enhancement, the energy loss and thermal management, as well as the driving and control. Meanwhile, the future development trend of high-repetition-rate solid-state pulsed power drivers was also discussed, providing a reference and basis for the research and exploration of technical routes related to such driver.

AbstractIntelligent flow field modeling methods, by integrating the strengths of deep learning in feature extraction and dynamic response prediction with architectural innovation potential in MDO (multidisciplinary design optimization), have emerged as research hotspot for achieving efficient modeling of complex flow systems and enhancing high-dimensional performance. The state-of-the-art in intelligent flow field modeling was systematically reviewed from two perspectives: data-driven approaches and physics-constrained methodologies. Three critical challenges, including acquisition of high-fidelity data, representation of complex boundary geometries, and establishment of robust physical constraints, were identified. Furthermore, a joint modeling framework that integrated aerodynamics and multidisciplinary coupling effects was expected to revolutionize the next generation of aircraft MDO paradigm through multi-scale physical information embedding and adaptive optimization mechanisms. A new idea for the deep integration of data knowledge and physical mechanisms was provided, aiming to inspire interdisciplinary innovations for intelligent flow field modeling in aerospace and other fields.

AbstractFor the new network communication challenges of efficient data interaction between components in open interactive environments, a novel C2N (computing and control network) was proposed. Aiming at the extreme requirements for efficiency, real-time performance, flexibility, and security, C2N adopts intelligent and simplified designs in protocol architecture, planning, application, and security design, providing high-performance and highly flexible basic network support for strong real-time collaborative fusion among heterogeneous resources. Based on a detailed investigation of relevant research work, key technologies of C2N were discussed, such as data link layer enhancement, remote direct memory access for sensor-controllers, and service-oriented sensing and control middleware. It also introduced the key technology research and test evaluation carried out by the network chip and system team of the National University of Defense Technology, and prospected future challenges and research directions to help China gain leading advantages in high-end equipment systems and innovative ecosystems.

AbstractPower semiconductor modules are the core energy conversion units in power converters. By optimizing their design, the power density can be significantly enhanced. However, current design methods lack systematic summaries. To address this, a systematic summary across four levels(material, chip, packaging and drive) was presented. This included utilizing wide bandgap materials, enhancing chip structure, adopting advanced packaging and improving gate drive design. The underlying principles behind these methods for increasing power density were summarized, and classified and compared the existing research on improving the power density of converters based on power semiconductor module design. The primary challenges in current research were combed, and the future development trend was forecasted.

AbstractAs a representative of the next generation of gyroscopes, atomic gyroscopes have become a focal point of research in the field of high-precision inertial navigation and have garnered significant attention due to its theoretically ultra-high precision, exceptional long-term stability, and immense potential for miniaturization and integration. Among them, the atomic interference gyroscope, as a type of atomic gyroscope, has attracted widespread interest in the field of inertial navigation. The development of atomic interference gyroscopes was systematically reviewed. Beginning with fundamental principles, the critical technical components including atomic source preparation, interferometric loop construction, and phase resolution were elaborated on. Through rigorous analysis, the intrinsic correlations between core performance parameters such as sensitivity and ultimate accuracy were established, while their mutual constraint mechanisms was elucidated. Furthermore, the physical origins of engineering bottlenecks including limited data update rates and narrow dynamic ranges were revealed. Finally, the future development directions and trends for atomic interference gyroscopes were outlined, emphasizing the need for in-depth research in several areas: solving external interference issues to improve accuracy, improving chip processing technology for miniaturization and integration, optimizing the combined inertial sensors, increasing data update rates, and exploring ways to expand dynamic range.

AbstractSpace mission design software spans the entire lifecycle of space missions and is regarded as the cornerstone of the aerospace industrial software system. Leveraging nearly three decades of technical expertise in the field of manned spaceflight, the research team from the National University of Defense Technology initiated the development of the independent industrial software ATK（aerospace tool kit） in 2020. By the end of 2024, the ATK 3.0 version was officially released, encompassing 5 major categories and 21 functional modules, including standard platform, visibility and coverage analysis, mission analysis, orbital design, and secondary development. The development of ATK has been deeply and continuously supported by China Manned Space Engineering exploring a collaborative research and development model characterized by "engineering-driven demand+centralized academic development". This software has had a significant impact in aerospace engineering, space security, and academic education, marking a solid first step toward replacing STK. The development history of ATK was reviewed, and the functional features was elaborated on. Focuses on analyzing its core technologies breakthroughs of ATK, such as large-scale software architecture design, computational kernel development, and orbital maneuver planning were selective analysed. While ATK faces challenges in enhancing its functionality and building its application ecosystem, its future development roadmap and strategic objectives were outlined.

AbstractSuccessful application of reinforcement learning in decision support, combinatorial optimization, and intelligent control has driven its exploration in complex industrial scenarios. However, existing reinforcement learning methods face challenges in adapting to graph-structured data in non-Euclidean spaces. Graph neural networks have demonstrated exceptional performance in learning graph-structured data. By integrating graphs with reinforcement learning, graph-structured data was introduced into reinforcement learning tasks, enriching knowledge representation in reinforcement learning and offering a novel paradigm for addressing complex industrial process problems. The research progress of graph reinforcement learning algorithms in industrial domains was systematically reviewed, summarized graph reinforcement learning algorithms from the perspective of algorithm architecture and extracted three mainstream paradigms, explored their applications in production scheduling, industrial knowledge graph reasoning, industrial internet, power system and other fields, and analyzed current challenges alongside future development trends in this field.

AbstractDiffusion models represent a novel type of generative artificial intelligence models. Compared to traditional networks such as generative adversative networks, variational autoencoders, and flow models, diffusion models are characterized by their robust training, high fidelity and diversity in generation, and strong mathematical interpretability, and so they are widely used in fields of computer vision, signal processing, multi-modal learning and so on. Diffusion models are capable of sufficiently learning and exploring the deep generative priors from the training images, providing a novel paradigm for solving inverse problems in image processing. In order to systematically sort out the development status of diffusion model, especially the latest progress in solving the inverse problem of image processing, the research of diffusion model for the inverse problem of image processing was reviewed. The basic principle and development status of diffusion model was expounded,the main technical route of using diffusion model to solve the inverse problem of image processing and some specific application results in this direction were emphatically introduced, and the future research directions were envisioned.

AbstractWith the vigorous development of the manufacturing industry, the problems such as environmental pollution an resource shortage have gradually become prominent, seriously affecting the sustainable development of society. Therefore, the transformation of manufacturing energy saving and carbon reduction is an inevitable requirement for global green and lowcarbon development. As one of the most important parts of the manufacturing systems, production scheduling can realize efficient and green operation of the manufacturing systems through the reasonable allocation of resources. Under the context of green manufacturing, the research of green shop scheduling problem has become a hot spot in the field of production scheduling. Therefore, a systematic review of the existing research since 2018 from the aspects of the green parallel machine scheduling problem, the green flow shop scheduling problem, the green job shop scheduling problem, the green flexible job shop scheduling problem, and the green distributed shop scheduling problem was conducted, the shortcomings of the existing research was summed up, and the direction of future research was pointed out.

AbstractAs an important energy source of solid rocket motors, the mechanical properties of composite solid propellants have always been the focus of attention in the engineering field. The macroscopic constitutive model and the fine-scale mechanical model in the characterisation of propellant mechanical properties was focused on. The development of the two types of models was systematically sorted out. The differences between the models were clarified. The applicable conditions of various models were pointed out. The difficulties and challenges of macro and fine mechanical models in the characterisation of propellant mechanical properties at the present stage were analysed. The proposal of mechanical models represented by cross-scale mechanical models will help to solve the problem of propellant mechanical property characterisation. The key in the future modelling of propellant mechanical characterization is the experimental research under complex conditions, focusing on the development of high precision and high performance multiscale numerical computation methods, as well as the integration of data-driven technology represented by artificial intelligence technology into model innovation.

AbstractILET(ionic liquid electrospray thruster), one of the electrostatic micro-thrusters, has recently become a hot topic for researchers. The emitter is the core component that significantly affects the thruster performance, so its manufacturing is considered as one of the key technologies for the ILET development. Combined with the operating principle and the development history of ILET, the characteristics of propellant transport and manufacturing requirements for all three types of emitters, namely capillary, externally-fed and porous emitters, were analyzed. Based on this, the typical manufacturing materials and related manufacturing technologies were reviewed, while the advantages and disadvantages of different manufacturing technologies such as ion etching were summarized and remarked. For the proven manufacturing method of ultrafast laser ablation based on porous material, the development suggestions including emitter design, novel material fabrication, and study on laser-matter interaction mechanism were given.

AbstractIn order to explore the key technologies of parafoil systems, including modeling, trajectory planning, and trajectory tracking control, to support their autonomous homing in wide application prospects in large-scale equipment airdrop replenishment, carrier rocket booster recovery, and natural disaster rescue applications. Through research on the development of parafoil systems both domestically and internationally, a comparative analysis and summary of the basic principles, commonly used methods, and cutting-edge technologies of the three key technologies were conducted, with a focus on the flexible modeling technology of parafoil systems in complex environments, trajectory planning technology in obstacle spaces, and trajectory tracking technology based on intelligent control strategies. A summary and outlook were made on the future development trends of key technologies for autonomous homing of parafoil systems, which can help researchers gain a comprehensive understanding of the research progress and development trends in autonomous homing of parafoil systems, and provide inspiration and reference value for further research in this area.

AbstractWith the rapid development of spacecraft rendezvous and proximity operation technology, the problem of orbital pursuit-evasion has gradually become a research hotspot in the aerospace field. From the perspective of dynamics and control, the research status of spacecraft orbital pursuit-evasion was reviewed. General form of the orbital pursuit-evasion problem model based on quantitative differential games was given, and various types of orbital pursuit-evasion problems were systematically sorted out. For the solution of pursuit and escape strategies, the advantages and disadvantages of various methods were analyzed for closed-loop strategy and open-loop strategy. Focusing on the combination of artificial intelligence algorithm and orbital pursuit and escape problem, the research status of orbital pursuit and escape strategy based on deep neural network and reinforcement learning was expounded. Regarding future prospects, development directions has been proposed, including the pursuit-evasion game situation analysis, the multi-spacecraft game control, the game dynamics and control under three-body problem.

AbstractThe development trajectory of the flying-wing aircraft was sorted out, encompassing the early evolutionary history to the current state of research, along with contemplation and forecasts regarding future directions. Meanwhile, several key control challenges associated with flying-wing aircraft were discussed, including attitude control in a wide-speed domain under nonlinear conditions, high-precision autonomous take off and landing control under multiple effect coupling, robust control issues with approximate aerodynamic models and under strong disturbances, as well as control allocation problems arising from multi-surface redundancy. Moreover, the discussion on flow control issues that were currently a focal point in flying-wing aircraft research were discussed in depth. The following research trend of active flow control technology was expounded.

AbstractThe drag-free control of the spacecraft is one of the key technologies to realize the ultra-static and ultra-stable operation of science platform for gravitational wave space detection. At present, the dynamics and control of the spacecraft system have been studied deeply by various research institutions at domestic and overseas, and different detection tasks have been proposed according to the requirements of different detection frequency bands. The design and control of spacecraft formation were introduced and analyzed in detail according to the exploration mission, and the principles and theoretical methods of drag-free and attitude control, high-precision inertial sensors and actuators involved were deeply dissected. The overall situation of demonstration and verification of drag-free spacecraft in orbit for space-based gravitational wave detection was detailed and analyzed. On this basis, the key problems required to be solved in the research of follow-up related were presented, and the research hotspots and trends in the methods of future dynamics and control of drag-free spacecraft systems were also pointed out.

AbstractIn order to further advance the development of visual speech learning, the task definition and research significance of visual speech generation was expounded and the difficulties and challenges were deeply analyzed in this field. Besides, the current status and development level of visual speech generation research was introduced, and the recent mainstream methods were sorted, classified and commented based on the difference of generation frameworks. At the end of the paper, the potential problems and possible research directions of visual speech generation were discussed.

AbstractIncreasing transparency of modern warfare has brought serious challenges to the survival of missile launching vehicle on the battlefield. Around the launcher anti-damage ability of analysis and evaluation technology, the threat of damage and damage mechanism faced by launcher were analyzed, current research status of four types of damage(shock wave, kinetic energy, thermal, and electromagnetic) from the perspective of the application of anti-damage capability assessment were elaborated, and different damage types in the evaluation of anti-damage capability and application directions in the analysis were putted forward; based on the vulnerability analysis space theory, the development process of equipment vulnerability analysis was summarized. It was considered that the logical transfer relationship from physical space to performance space was the key to the vulnerability analysis of launchers at present. Research trends of vulnerability criteria were introduced from the physical criteria, performance criteria and classification criteria, and the key criteria for vulnerability of launchers was proposed. Research concept and the main problems faced by analytical methods of the anti-damage capability of the launcher were explicitly described. Research conclusions can provide references for the analysis and evaluate related research of the anti-damage capability of the missile launching vehicle.

AbstractIt is of great significance to study GaN(gallium nitride) power devices and their radiation effects to meet the needs of space applications and promote the construction of a new generation spacecraft. Main structures and working principles of GaN power devices were introduced. Research progress of total ionizing dose effect and single event effect of GaN power devices in recent years was reviewed. Degradation and damage mechanisms of GaN devices caused by radiation effects were analyzed and discussed. Research results show that GaN power devices have strong resistance to total ionizing dose. However, GaN power devices are prone to leakage and single event burnout due to their weak resistance to single event burnout, and most of the burnout points occur at the drain side of the gate edge. Research on the radiation damage mechanism of GaN power devices lacks authoritative theories and needs to be further mastered to provide theoretical support for their space application. GaN power devices with planar structure are the current mainstream technical solutions. Monolithic integration, high frequency and miniaturization are the development directions of GaN power devices in the future.

AbstractHALE(high-altitude long-endurance) solar-powered aircrafts are the research frontiers, they can staying airborne for several months, and can form new application ability named "long-endurance+station-keeping". The three-stage development process of HALE solar-powered aircrafts was systematically summarized, including early exploration stage, rapid development stage and operational capability demonstration stage, and typical development plans aboard were introduced. Key technology challenges were analyzed, including aerodynamic configuration design, energy storage battery, high altitude propulsion, large scale structure and flight control, and the suggestions for research directions were proposed. All those can provide reference for innovation development of HALE solar-powered aircrafts.

AbstractNeural architecture search is a task that aims to automatically search for the optimal neural network structure for different tasks, which is of great importance and inevitability in the joint development of deep learning and computer vision to the current stage. A comprehensive review of the research on neural network search was provided. In specific, the definition and significance of neural architecture search were introduced, and the difficulties and challenges faced in relevant research were deeply analyzed. Based on this, the mainstream search strategies was elaborate and summarize; Finally, the potential problems and possible future research directions were summarized and discussed to promote further development in this field.

AbstractThe novel non-volatile MRAM(magnetic random access memory) has the advantages of fast read and write speed, long data retention time and low power consumption, which attracts wide attention from researchers. Its excellent anti-irradiation capabilities are explored in depth, and further applications in aerospace and other fields are expected. The industrial development, technological changes and applications of MRAM were reviewed, the mature MRAM products of recent years were listed, and the advantages and disadvantages of different generations of MRAM were analyzed. The radiation effects of MTJ(magnetic tunnel junction) and read/write circuit based CMOS(complementary metal oxide semiconductor) were discussed. The recent achievements in anti-radiative hardening design for MRAM were summarized. The development prospect of anti-irradiation MRAM in aerospace field and even nuclear energy field was prospected.

AbstractCognitive electronic warfare is usually defined as a form of electronic warfare that is based on electronic warfare equipment with cognitive performance and focuses on autonomous interactive electromagnetic environment learning capability and dynamic intelligent confrontation task processing capability. Since it was first proposed, it has attracted extensive attention from researchers and scholars at home and abroad for its advantages of accurate perception, strong reasoning and fast decision-making. With the continuous emergence of new concepts, technologies and applications of artificial intelligence, cognitive electronic warfare has stepped into a brand new stage of development. In order to capture its future development direction, the connotation of the concept of cognitive electronic warfare was summarized and enriched from the perspective of artificial intelligence, the development of cognitive electronic warfare and typical foreign projects were sorted out, the framework and architecture of cognitive electronic warfare system was built, a comprehensive and systematic review of the key technologies of cognitive electronic warfare was conducted from the aspects of perception, judgment, decision-making, etc., and the challenges and development trends of cognitive electronic warfare were summarized.

AbstractGNSS/INS ultra-tight integrated navigation system has become a research hotspot in the field of integrated navigation due to its high positioning accuracy, excellent dynamic performance and strong anti-jamming ability. The principle of GNSS/INS ultra-tight integration was introduced, and the advantages and features of ultra-tight integration mode relative to other integration modes were compared based on the analysis of the technical principle. The domestic and international research status was introduced, represented by ultra-tight integration under high dynamics and MIMU/GNSS ultra-tight integration. The key technologies such as fault-tolerant control technology, neural network assistance, and multi-sensor assisted ultra-tight integration were summarized, and the prospect of GNSS/INS ultra-tight integration towards low cost, high precision and strong stability was prospected.

AbstractWith the convergence trend of high performance computing, big data processing, cloud computing and artificial intelligence computing, the converged network of high-performance computing network and data center network becomes an important trend. The current research status of converged network was analyzed, and the representative converged networks were described in detail to comprehensively show the latest technologies and trends. The challenges faced by the converged network were put forward, and the trends of converged network were proposed, including the convergence and differentiation coexistence of the converged network protocols, the performance acceleration of the converged network based on in-network computing, and the performance optimization of the converged network for emerging applications.

AbstractIn order to improve the service life of nickel-based single crystal blades and solve the key technology of aeroengine turbine and gas turbine, domestic and overseas researchers carried out a large number of research on the failure and damage mechanism of nickel-based single crystal superalloys under service conditions in recent years. The research achievements and progress of fatigue, creep and thermomechanical fatigue damage mechanism of nickel-based single crystal superalloys under service conditions were concluded. In addition, in view of the time and cost increase caused by a large number of experiments, the research works and achievements in life prediction methods of nickel-based single crystal superalloys in recent years were summarized, and the difficulties and challenges in life evaluation and failure analysis of nickel-based single crystal superalloys were proposed.

AbstractBased on the technical status and development trend of civil aircraft operation reliability research, the requirements of civil aircraft operation reliability research were expounded according to the current type design, development and actual situation of in-service aircraft. By reviewing the research progress and engineering application status of civil aircraft operational reliability theory, the research status and problems of civil aircraft operational reliability are elaborated from six aspects:operation data acquisition and processing, operational reliability analysis method, operational reliability prediction feedback technology, optimization design based on operational reliability, optimize maintenance tasks, and comprehensive management platform for operational reliability. The future development direction of operation reliability research of civil aircraft is prospected.

AbstractInternal waves, occurring in stratified ocean, are ubiquitous in the world oceans. It is of great significance for our country′s marine development to study the generation and evolution of internal waves. Based on the internal wave theory of two-layer and three-layer fluid systems, the KdV(Korteweg-de Vries) internal wave theory, MCC(Miyata-Choi-Camassa) internal wave theory, HLGN(high-level Green-Naghdi) internal wave theory and Dubreil-Jacotin-Long internal wave theory, which were widely used at home and abroad, were selected to review their research progress. The advantages and limitations of different internal wave theories were discussed from mathematical models, theoretical research and numerical simulations. In the view of mathematical derivation, it is proved that MCC internal wave theory is equivalent to the first-level HLGN internal wave theory.

AbstractIn order to master the atomization characteristics of oscillating spray and its relationship with unstable combustion, research and development of gas-liquid coaxial swirl injectors and liquid-liquid coaxial swirl injectors, which are widely used in liquid rocket engines, are reviewed from three aspects of excited oscillation, self-pulsation, and interactions of spray oscillation with combustion stability, so as to deepen our understanding of them. According to the review, for the excited oscillation, the research on the upstream pressure oscillation caused by flow oscillation of supply system under normal temperature and pressure conditions is relatively sufficient. However, the research on the backpressure oscillation caused by pressure oscillation in the combustion chamber and the research on the excited oscillation of spray under supercritical conditions are lack. For the self-pulsation, the current research is focused on the liquid-centered coaxial swirl injectors. There are few studies on the gas-centered coaxial swirl injectors and liquid-liquid coaxial swirl injectors. The optical diagnosis technology is far from enough to extract the single combustion flow field information.

AbstractMicro-soft robots with high compliance, low energy consumption and high energy density have wide application prospects in complex environments such as pipeline maintenance and battle field reconnaissance. Energy and actuator play a decisive role in the motion modes and performances of micro-soft robots. In order to make more researchers understand the research progresses of the existing flexible driving technology and their energy sources, the typical driving methods based on physical energy driving, chemical energy driving and biological hybrid driving were summarized and analyzed. The shortcomings and future development of the existing flexible driving technology and their energy sources were discussed and summarized, which can provide reference for the development and improving performance of the flexible drive technology of soft robots in the future.

AbstractVisual system is an important part of autonomous unmanned system. The raindrops attached to the surface of the camera lens will produce artifacts in the image, resulting in the degradation of image quality, which will significantly affect the performance of the visual system. The detection and removal methods of attached raindrops in recent years were comprehensively and deeply researched. The essence of the problem was condensed, and the existing raindrop imaging models were summarized. Different technical methods were sorted out from three directions:model-based, data-driven and camera system-based, then the development of deep network model was summarized from two aspects of network architecture and loss function. The existing datasets of attached raindrops were summarized, and the performance of some algorithms was compared through the experimental results. The main problems in the task of raindrop detection and removal were discussed, and the possible development direction in this field was prospected.

AbstractThe novel UAV (unmanned aerial vehicle) ground station with advanced control capabilities such as immersive display, intelligent assistance, and naturalized human-computer interaction has become a hot research topic in the field of UAV control. To analyze the technical aspects, the functional points and designs concepts of a series of advanced ground stations for UAVs at home and abroad were systematically compared. The technical system composition from the OODA (observe, orient, decide and act) loop of UAV ground station command and control were summarized and refined. The key techniques such as task environment construction, battlefield situation immersive display, intelligent assisted decision and naturalized human-computer interaction were analyzed and pointed out. The main research methods of various techniques were deeply analyzed, and the current challenges and future development trends of UAV advanced ground stations were also studied and judged. In addition, it provides guidance and reference for the development of novel ground stations.

AbstractVINS (visual-inertial navigation systems) solve a series of parameters required for state estimation through initialization, such as scale, gravity vector, velocity, inertial measurement unit′s bias, etc., to improve the accuracy of navigation positioning and environmental perception of the system. The initialization methods of VINS can be divided into three categories according to the sensing information fusing mode:joint initialization, disjoint initialization and semi-joint initialization. Based on the existing research work, the current mainstream initialization methods of VINS were reviewed from four aspects:basic theory, development and classification, existing methods, performance evaluation, and the future development trends were summarized, which is helpful to have a general understanding of VINS initialization methods and grasp its development direction.

AbstractIn order to master the current development status and development trends of memristor based neuromorphic chips, the existing memristor based neuromorphic chips and architectures were investigated. The memristor array structure and integration process, anterior and posterior neuron circuits, multi-array interconnection topology and data transmission strategy used in the chip, as well as the system simulation and evaluation methods used in the chip design process were compared and analyzed. It is concluded that the current circuit design of memristor based neuromorphic chips still need to solve the problems of limited resistance states, large device parameter fluctuation, complex array peripheral circuits, small integration scale, etc. It is pointed out that the actual application of this type of chip still faces challenges such as the improvement of memristor production process, improvement of development tool support, special instruction set development, and determination of typical traction applications.

AbstractThe basic principle, representative methods, and state-of-the-art research of the sub-module related research within the general framework of cooperative maneuvering flight planning from single UAV (unmanned aerial vehicle) maneuvering flight to multi-UAV cooperative planning were introduced. It mainly included real-time navigation map construction, discrete-space path planning, continuous-space trajectory planning, hybrid planning based on discrete-space and continuous-space, and multi-courses/trajectories cooperative planning. The next research directions were proposed based on the major technologies of the planning framework.

AbstractStealth aircraft has gradually become a great power, and will continue to play an important role, making stealth technology become the key technology of aircraft design. RCS(radar cross section) measurement of stealth aircraft is a necessary step to design, manufacture and maintain stealth aircraft. The basic process of RCS measurement of stealth aircraft was reviewed from three aspects:RCS test of scaled model, outdoor RCS test of full-scale aircraft and indoor near-field test of full-scale aircraft, the theoretical basis of RCS near-field measurement of stealth aircraft was summarized, and the near-field RCS measurement technology with imaging diagnosis function was analyzed intensively. The development trend and key technologies of stealth aircraft RCS measurement were prospected, which is helpful to have a general understanding of RCS measurement of stealth aircraft and grasp the development direction of RCS measurement.

AbstractBased on demand of multiple time scale dynamic characterization of power electronic devices and their combination, the recent research progress and achievements on the widely used full-control power electronic devices—IGBTs(insulated gate bipolar transistors), were analyzed systematically, including the multiple time scales electro-thermal modeling of high power IGBTs and their combinations, quantitative failure evaluation methods based on the multiple time scales model and the assisted multi-rate simulation method. Furthermore, applications of the models were introduced in power electronic instruments design. In conclusion, the dynamic characterization method of high power IGBTs and their combinations under multiple time scales were presented from four aspects of modelling method, reliability evaluation, simulation method and application design, which can bring theoretical and technical support of power electronic devices to precise design of power electronic hybrid system.

AbstractIn view of the wide application prospect of intelligent ammunition, the development of two-dimensional trajectory correction projectile, main correction mechanism scheme and guidance control technology were summarized. The development process of the two-dimensional trajectory correction projectile was reviewed, aiming to reveal the development principle. Several main correction schemes were discussed, and the function characteristics and research difficulties of each mechanism were analyzed. Based on the requirements of the two-dimensional trajectory correction projectile, the research status of its control technology was summarized from three aspects:aerodynamic identification and state estimation algorithm, parameter optimization algorithm and guidance law. The rapid development of intelligent algorithm in recent years, especially the application of neural network theory in the field of control algorithm was focused on. The main technical difficulties and the future development direction of the control research of the two-dimensional trajectory correction projectile, which provides ideas for the design, were pointed out.

AbstractThe application requirements of UAV (unmanned aerial vehicle) swarm communication payload technology based on FSO (Free Space Optical) were summarized, and the current status of FSO technology and application at home and abroad UAV payloads was discussed. The development prospect of the payload technology of UAV swarm based on FSO communication in high-speed mobile communication environment was also analyzed. Furthermore, a profound analysis on the key technologies in FSO communication links applied to UAV swarm was conducted. Predictably, FSO-based communication payload will be used widely for wide-bandwidth communication networking of UAV swarm in the future.

AbstractLayerwise theory, proposed by Reddy, is a 3D analysis method for accurately analyzing composite laminated plates and shells. Without introducing any deformation and stress hypothesis, layerwise theory, compared with the classical equivalent single layer theories, has greater advantages for static and dynamic responses analysis of thick composite laminated plates and shells, especially for local interlaminar effects analysis. A review and recent research progress of the layerwise theory were presented, and its numerical solutions and applications were demonstrated as well. The basis of layerwise theory and its recent development were introduced. The implementation of layerwise finite element method and its refined models were discussed. The employment of layerwise theories for conducting static and vibration analyses and the damage model analysis of composite laminated plates and shells were outlined. And several future research trends were recommended in the end.

AbstractThe platelet technology has been in rapid development because of several features, including the special structure of flow channel, the precise size and location, and can provide solutions to difficult thermal and fluid flow problems. As a result, the platelet technology is a major technological innovation in the history of science and technology. The characteristics and development of platelet fluid devices were briefly introduced. Some typical new applications at home and abroad in recent years, such as platelet injector, platelet transpiration cooling nose-tip, platelet fluid mixer, platelet thruster of high speed ship and platelet muffler were summarized. Finally, the correlation of processing of platelet technology and 3D printing technology was described.

AbstractHigh-precision positioning and navigation in GPS(global positioning system) denied environments is a key technology for aircraft achieving autonomous scout, cruise, and strike. Vision navigation has the advantages of passive-type, low cost, and avoidable accumulated errors avoidable, etc. The fusion of vision and inertial navigation can give full play to their advantages and achieve the purpose of high-precision positioning. Firstly, the development of aircraft positioning technology based on multi-modal image matching assisted inertial navigation was summarized. Then this technology was elaborated in five aspects:the vision-internal calibration, multi-modal image matching, attitude algorithm, data fusion, and back-end optimization. Finally, four possible future directions were proposed as follows, two types of passive positioning combined navigation systems based on deep learning, multi-modal image matching and inertial navigation. The four possible future directions provide a reference for realizing multi-modal image matching assisted inertial navigation aircraft positioning technology.

AbstractThe accurate navigation of the underwater vehicle plays an important role in the process of the ocean utilization and development. The problem of restraining the accumulation errors of the underwater navigation over time was discussed and analyzed in detail. Firstly, the development history of the inertial devices was briefly described. Secondly, the advantages and disadvantages of each navigation system were compared in detail, the research status of the gravity-aided navigation at home and abroad were introduced, and the demand for the high-precision navigation of the underwater vehicles and the scientific problems of insufficient spatial resolution of the global marine gravity reference map were analyzed. Finally, the idea and technical route of obtaining the high spatial resolution and high precision global marine gravity reference map by GNSS-R altimetry constellations are proposed in order to improve the accuracy of the underwater gravity-aided navigation.

AbstractVolume rendering is an effective method to visualize complex physical features in large-scale scientific data with high expressiveness, the difficulties in processing huge amount of data and capturing complex features, however, are still a great challenge to volume rendering. To address the challenges and improve efficiency and effect of volume rendering, researchers conducted in-depth research on volume rendering algorithms from three aspects. On the one hand, it is an effective way to improve the efficiency of volume rendering by sharing computation with lots of processor cores so as to reduce the computational amount of one processor core. On the other hand, by fully exploring the intrinsic characteristics of three-dimensional data fields, data reduction methods can greatly decrease the amount of data in the rendering process and thus reduce the overhead of a volume rendering algorithm. In addition, feature analysis and enhancement techniques can also be integrated into volume rendering algorithms, thus complex physical features are highlighted from the data fields and high-quality rendering of scientific data is achieved. A survey of recent advances on volume rendering techniques was presented and various research methods were analyzed. In the end, this paper makes prospection for future research directions on volume rendering of large-scale scientific data, including application-driven feature volume rendering, feature-based data reduction in volume rendering, hardware-adapted multi-level acceleration of volume rendering and in-situ intelligent volume rendering.

AbstractAlong with the maturity of high-nonlinearity optical fiber manufacturing technology and the improvement of the performance of fiber lasers, the supercontinuum sources have entered a period of rapid development. Supercontinuum generation by using optical fibers as the non-linear media has become a research hotspot. The technical schemes and recent progress of supercontinuum generation were been reviewed from three different bands:visible, near-infrared and mid-infrared. At present, the output power of the visible and near-infrared supercontinuum sources broke through 100 W. At the same time, many new schemes such as supercontinuum generation in multi-core photonic crystal fibers, fiber amplifiers and random fiber lasers were developed. The output power of mid-infrared supercontinuum generation by using fluoride and tellurite fibers as non-linear media, also reached 10 W. The output spectrum of supercontinuum generation with chalcogenide optical fibers as non-linear medium was extended to more than 12 μm.

AbstractThe history of precision guidance technologies was reviewed, and the challenges and main developing trends of imaging and detecting technologies for precision guidance were illustrated. Combined with the recent developments of the emerging technologies such as terahertz, quantum and metamaterial, the backgrounds, developing venation, basic principles and advantages of three typical advanced imaging and detecting technologies, namely, terahertz radar, quantum radar and metamaterial radar were expounded. These advanced techniques may have the potential to provide feasible approaches for precision guidance technology to overcome the challenges brought by the future new warfare form. The analysis results will provide some positive guidance and is of significance for improving the strike and intercept effectiveness of the precision guided weapon systems.

AbstractComprehension of complexity is one of the key challenges in science and technology. Complexity is a very important conception in interdisciplinary systems science, and is significant to researchers. The basic semantic background on system complexity was presented and the various definitions of complexity domestically and overseas were analyzed. On the basis of the classification of ontology and epistemology, a taxonomy of complexity was described on the basis of the state-of-the-art works on complexity definition. Meanwhile, a category of complexity measurements and the corresponding mathematical tools were proposed. Examples were given for the efficiency of complexity classification and measures.

AbstractUnder the dynamic equilibrium among diffraction, dispersion, Kerr effect and multiple photons ionization, a self-guiding filament formed by femtosecond laser with long propagation distance can be constructed, which is accompanied by a narrow plasma channel. In order to control the propagation features of filamentation explicitly in air, a way to effectively regulate filamentation propagation modes and spatio temporal distributions has become a research hotspot. On the basis of introducing the physical model of filamentation briefly, a general overview of controlling filamentation divided by two parts was presented in this review: temporal modulations and spatial modulations. In particular, the latter consists of modulations designed by phase, amplitude and special beams. Our findings suggest that unique filaments controlled by initial modulations can offer advantages and fundamentals for the realization of numerous potential applications.

AbstractAs the key technology of reliability evaluation for hull structure in-service, the merits of the reliability assessment theories determines the effectiveness and confidence level of the reliability evaluation result directly. The development course and current research situation of traditional reliability assessment theories and non-probabilistic reliability assessment theory were elaborated in the view of calculation principle, computing of measurement index and engineering application. Simultaneously, the advantages and disadvantages of all current reliability assessment theories that applied in hull structure in-service were analyzed and summarized. The future research outlook was developed and the focus in the study of hull structure reliability was outlined.

AbstractThe rapid development of the Internet also causes more and more network threats. How to detect the network threats in a real-time and accurate manner becomes one of the key technique issues. The alert-correlation-based network threat detection technique is becoming the research hotspot, which couples with the widely used security products and fully exploits the relation between abnormal events to reconstruct the attack scenario. Starting from the features of network threats and security environment, the requirements and classification of network threat detection were introduced. Then the basic concepts and system model of alert-correlation-based network threat detection technique were illustrated in detail. The key module of the model, aler correlation method, and the fundamentals and features of different kinds of typical algorithm were studied in detail, including causal-relation-based method, case-based method, similarity-based method and data-mining-based method. Furthermore, three kinds of representative detection system architectures were discussed with practical instances, namely centralized architecture, hierarchical architecture and distributed architecture. Finally, based on the analysis of recent research work, the future work is discussed and outlined.

AbstractThe basic problem of gliding guidance for hypersonic vehicles was proposed, and the difficulties of complicated multiple constraints, maneuver requirements, and parameter perturbation in the course of gliding guidance were analyzed. The corresponding research status at home and abroad was surveyed, and the problems were also pointed out. On this basis, the key problems required to be solved at present in the research of gliding guidance for hypersonic vehicles were presented, and the research hotspots in the methods of future gliding guidance were also pointed out. 

AbstractIn order to provide a guide for specific investigations on WTBVFT(wind tunnel based virtual flight testing) techniques, the test system and key technologies of WTBVFT for the evaluation of FCS (flight control system) were analyzed. Based on the deficiencies of the traditional FCS evaluation methods, the advantages of WTBVFT for evaluation of FCS were analyzed. According to the common constitution of attitude control loop and guidance control loop used by FCS, the test system and working principle of WTBVFT for FCS evaluation were presented. The main differences between the WTBVFT system and the hardware-in-the-loop simulation system were analyzed. The key technologies of WTBVFT for FCS evaluation were also analyzed, including WTBVFT evaluation methods, aircraft model design technique, FCS modification technique, and model support technique.

AbstractElectromagnetic launch technology is an inevitable trend among methods of launch in the future. The principle and technology characteristics of electromagnetic launch is analyzed, three branches of electromagnetic launch technology development overseas in electromagnetic ejection, electromagnetic railgun and electromagnetic pushing were studied, and the key technology of electromagnetic launch was summarized. Furthermore, the development strategy and the extension application prospect of electromagnetic launch technology was proposed.

AbstractIn recent years, the network dependency and interdependent networks have become a research hotspot in the field of complex network, but literature about the overview of related research progress is still very rare. Based on the systematic research of domestic and overseas literatures, the percolation theory of the interdependent networks was briefly introduced, and the cascading failure process of the interdependent networks was described. Then the related progress was summarized from three aspects that can affect the robustness of interdependent networks: characteristics of sub network, type of dependency edge, the combination of sub networks. Finally, the future development direction of interdependent networks was prospected in both theoretical and practical aspects.

AbstractTrajectory optimum design for flight vehicles using pseudo-spectral methods has been a hot research direction in recent years, but studies about the overview of this field are very few. Based on the systematic research of domestic and overseas related literatures, the basic principles of several pseudo-spectral methods which have a wide range of applications in aerospace field were expounded; the thoughts and formulas for transforming continuous optimal control problems into nonlinear programming problems were concluded; the applications of pseudo-spectral method in the trajectory optimum design for flight vehicles were summarized; the development directions of pseudo-spectral method and its application in trajectory optimization design for flight vehicles were discussed.

AbstractWith the increase of domestic and foreign launching tasks, it is becoming a serious challenge that plenty of failure or invalid spacecrafts in the process of space resources recycling. The active debris removal can be regarded as an effective and fundamental means that can realize the reuse of space resources and safe disposal. The concept of active debris removal is clarified and its development process also is analyzed. Some key techniques, such as relative navigation, coordinated control, capture method and device for non-cooperative target, are proposed. It will provide some fruitful reference for our country′s active debris removal in future.

AbstractBased on brief introduction of the conception of underwater terrain-aided navigation, the key problems and research progress of underwater terrain-aided navigation were introduced from the view of terrain aided navigation algorithm, underwater digital map technology, and experimentation. The direction of research and development of application was pointed out as well.