查看更多>>摘要：This paper gives a definition of the Industrial Internet and expounds on the academic connotation of the future Industrial Internet.From this foundation,we outline the development and current status of the Industrial Internet in China and globally.Moreover,we detail the avant-garde paradigms encompassed within the National Natural Science Foundation of China(NSFC)'s"Future Industrial Internet Fundamental Theory and Key Technologies"research plan and its corresponding management strategies.This research initiative endeavors to enhance in-terdisciplinary collaborations,aiming for a synergistic alignment of industry,academia,research,and practical implementations.The primary focus of the research plan is on the pivotal scientific challenges inherent to the future industrial internet.It is poised to traverse the"first mile",encompassing foundational research and pi-oneering innovations specific to the industrial internet,and seamlessly bridges to the"last mile",ensuring the effective commercialization of scientific and technological breakthroughs into tangible industrial market applica-tions.The anticipated contributions from this initiative are projected to solidify both the theoretical and practical scaffolding essential for the cultivation of a globally competitive industrial internet infrastructure in China.
查看更多>>摘要：With the advent of the Internet of Everything(IoE),the concept of fully interconnected systems has become a reality,and the need for seamless communication and interoperability among different industrial systems has become more pressing than ever before.To address the challenges posed by massive data traffic,we demonstrate the potentials of semantic information processing in industrial manufacturing processes and then propose a brief framework of semantic processing and communication system for industrial network.In particular,the scheme is featured with task-orientation and collaborative processing.To illustrate its applicability,we provide examples of time series and images,as typical industrial data sources,for practical tasks,such as lifecycle estimation and surface defect detection.Simulation results show that semantic information processing achieves a more efficient way of information processing and exchanging,compared to conventional methods,which is crucial for handling the demands of future interconnected industrial networks.
查看更多>>摘要：Defining and measuring resilience using a unified framework has been a topic of intense research.This article presents a perspective on how resilience could be quantitatively assessed through a set of indices.It starts with a brief explanation of resilience in the context of supply chain and a quick summary of existing quantitative measures of resilience.It then discusses how resilience could be quantified in a constructive manner so that the resulting metrics are representative of the performance throughout the system's life cycle.In particular,it is proposed that resilience should be evaluated according to different time periods,i.e.before,during and after a disruption has occurred.Four dimensions of resilience,namely reliability,robustness,recovery and reconfigura-bility,can then be used to make up a set of indices for resilience.For numerical illustration,these indices are computed based on recovery data arising from Hurricane Sandy in October 2012.Finally,it is postulated that resilience will be the performance metric that complements productivity and sustainability as the third pillar for measuring success of organizations,and in turn,that of sovereign countries in their quests for developing smart cities.
查看更多>>摘要：Industrial Internet upgrades the traditional industrial manufacturing to digitization,networking and intellec-tualization era,which calls for brand-new technology supports.As a promising solution,the emergence Digital Twin(DT)offers enhanced digital mapping capability with strong feasibility,security,economic and intelligence,which fits well with the concept of Industrial Internet.In this paper,we focus on establishing a new reference architecture of DT to support the development of Industrial Internet.It is composed of three interdependent layers(i.e.,physical layer,DT layer and DT networks layer)and four critical attributes(i.e.,privacy,security,awareness and real-time).We illustrate our perspectives for the functionality and relationship of the three layers,and features and feasible solutions of the four attributes.With those efforts,the proposed DT architecture can provide both smart manufacturing and networked services for Industrial Internet era.Moreover,we also illustrate the relevant and open challenges.Finally,the conclusion and future perspective are pointed out.
查看更多>>摘要：As a result of the growing complexity of industrial Internet applications,traditional hardware-based network de-signs are encountering challenges in terms of programmability and dynamic adaptability as they struggle to meet the real-time,high-reliability transmission requirements for the vast quantities of data generated in industrial environments.This paper proposes a holistic software-defined deterministic network(HSDDN)design solution.This solution uses a centralized controller to implement a comprehensive software definition,ranging from the network layer down to the physical layer.Within the wireless access domain,we decouple the standard radio-frequency modules from baseband processing to realize a software-defined physical layer,which then allows us to adjust the data transmission cycles and tag the trigger rates to meet demand for low-power,high-concurrency transmission.Within the wired network domain,we integrate software-defined networking with time-sensitive networking and propose a coordinated design strategy to address routing and the deterministic scheduling prob-lem.We define a set of constraints to ensure collaborative transmission of the periodic and aperiodic data flows.To guarantee load balancing across all paths and timeslots,we introduce the Jain's fairness index as the opti-mization objective and then construct a nondeterministic polynomial-time(NP)-hard joint optimization problem.Furthermore,an algorithm called Tabu search for routing and scheduling with dual-stages(TSRS-DS)is proposed.Simulation experiments demonstrate the effectiveness of the proposed HSDDN architecture.
查看更多>>摘要：Since solid-liquid interfacial nanobubbles(INBs)were first imaged,their long-term stability and large contact angle have been perplexing scientists.This study aimed to investigate the influence of internal gas density and external gas monolayers on the contact angle and stability of INB using molecular dynamics simulations.First,the contact angle of a water droplet was simulated at different nitrogen densities.The results showed that the contact angle increased sharply with an increase in nitrogen density,which was mainly caused by the decrease in solid-gas interfacial tension.However,when the nitrogen density reached 2.57 nm-3,an intervening gas mono-layer(GML)was formed between the solid and water.After the formation of GML,the contact angle slightly increased with increasing gas density.The contact angle increased to 180° when the nitrogen density reached 11.38 nm-3,indicating that INBs transformed into a gas layer when they were too small.For substrates with different hydrophobicities,the contact angle after the formation of GML was always larger than 140° and it was weakly correlated with substrate hydrophobicity.The increase in contact angle with gas density represents the evolution of contact angle from macro-to nano-bubble,while the formation of GML may correspond to stable INBs.The potential of mean force curves demonstrated that the substrate with GML could attract gas molecules from a longer distance without the existence of a potential barrier compared with the bare substrate,indicating the potential of GML to act as a gas-collecting panel.Further research indicated that GML can function as a chan-nel to transport gas molecules to INBs,which favors stability of INBs.This research may shed new light on the mechanisms underlying abnormal contact angle and long-term stability of INBs.
查看更多>>摘要：Quasi-parametric chirped-pulse amplification(QPCPA),which features a theoretical peak power much higher than those obtained with Ti:sapphire laser or optical parametric chirped-pulse amplification,is promising for future ultra-intense lasers.The doped rare-earth ion used for idler dissipation is critical for effective QPCPA,but is usually not compatible with traditional crystals.Thus far,only one dissipative crystal of Sm3+-doped yttrium calcium oxyborate has been grown and applied.Here we introduce optical means to modify traditional crystals for QPCPA applications.We theoretically demonstrate two dissipation schemes by idler frequency doubling and sum-frequency generation with an additional laser.In contrast to absorption dissipation,the proposed nonlinear dissipations ensure not only high signal efficiency but also high small-signal gain.The demonstrated ability to optically modify crystals will facilitate the wide application of QPCPA.
查看更多>>摘要：Based on the recent association of IceCube TeV and PeV neutrino events with gamma-ray bursts(GRBs)by considering the Lorentz violation of neutrinos,we provide a new estimate on the GRB neutrino flux with a more significant result compared to the previous constraint by the IceCube Collaboration.Among these 24 neutrino"shower"events above 60 TeV,12 events are associated with GRBs.Such a result is compatible with the prediction from GRB fireball models.Analysis of track events provides a consistent result with the shower events to associate high energy cosmic neutrinos with GRBs under the same Lorentz violation features of neutrinos.We also make a background estimation and reveal GRBs as a significant source for the ultra-high energy IceCube neutrino events.Our work supports the Lorentz violation and CPT-violation of neutrinos,indicating new physics beyond relativity.
查看更多>>摘要：We study theoretically and experimentally the acoustic Purcell effect induced by quasi-bound states in the contin-uum(quasiBICs).A theoretical framework describing the acoustic Purcell effect of a resonant system is developed based on the system's radiative and dissipative factors,which reveals the critical emission condition for achieving optimum Purcell factors.We show that the quasiBICs contribute to highly confined acoustic field and bring about greatly enhanced acoustic emission,leading to strong Purcell effect.Our concept is demonstrated via two coupled resonators supporting a Friedrich-Wintgen quasiBIC,and the theoretical results are validated by the experiments observing emission enhancement of the sound source by nearly two orders of magnitude.Our work bridges the gap between the acoustic Purcell effect and acoustic BICs essential for enhanced wave-matter interaction and acoustic emission,which may contribute to the research of high-intensity sound sources,high-quality-factor acoustic devices and nonlinear acoustics.
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