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To investigate the damage evolution and failure mechanisms of fiber-reinforced composite materials under complex conditions, this study conducted in situ X-ray computed tomography (CT) compression and tensile tests on plain weave two-dimensional woven SiC/SiC composite materials. The obtained CT in situ image data captured the behavior of materials during loading and after failure. Using the image reconstruction of CT data, the actual microstructure and damage evolution of the material under six consecutive loading levels were accurately revealed. Three-dimensional visualization models of the composite material were established using image processing software to analyze the damage evolution under compression and tension, and the failure mechanisms were compared. The results showed that the compression and tension failure mechanisms of SiC/SiC composite materials were similar, with the transverse cracking of the matrix being the first mode of damage, followed by delamination between layers and longitudinal matrix cracking of fiber bundles. Specifically, in terms of compression failure, the strength of the fiber bundle itself has a greater influence, and fiber fracture is the main cause of ultimate material failure. On the other hand, the primary cause of tensile failure is the presence of porosity defects generated during material fabrication. Consequently, the tensile material fails earlier and can withstand lower loads.

The concept and technologies of computing-network integration are still in the early stage of development. Research on computing task scheduling and network interconnection are still inadequate. Therefore, it is urgent to understand the developmental trend of the intelligent connection computing network technology (ICCNT) and propose a strategic conception and development routes for the independent innovation of ICCNT in China. This study analyzes the major challenges faced by the existing information network technologies and summarizes the developmental trends of computing-network integration. It also proposes a core architecture of the ICCNT and clarifies its development goals and expected performance. The development path of ICCNT is explored, covering key technologies such as diversified protocol support, integrated control of network, storage, and computing, intelligent arrangement of service functions, and endogenous security structure, as well as demonstration applications in the smart park network, vertical industry network, and data center network scenarios. Furthermore, we suggest innovating ICCNT systems, expanding the demonstration applications of ICCNT, and accelerating the implementation of ICCNT products, thereby promoting the evolution and application of ICCNT.

Cyber resiliency engineering is a technical approach embraced by countries and regions such as the United States and Europe to implement digital transformation and address network security challenges under new circumstances. It aims to keep the barriers to entry high for digital technologies based on the cyber resilience standard and to improve the digital infrastructure security capability of China from both the application service and device supply sides. This study focuses on the impact and challenges brought by the initiatives of cyber resiliency engineering in the United States and Europe on the development of new-generation network information technology in China. It starts from a concept introduction of resilience, cyber resilience, and cyber resiliency engineering. Subsequently, it elaborates on the application progress of cyber resiliency engineering in the United States and Europe in terms of policy drivers, strategic considerations, and development dilemmas. Moreover, the study goes further to propose a dynamic heterogeneous redundancy architecture based on an endogenous security and safety (ESS) theory. It describes and illustrates the intrinsic mechanism, basic concepts, and application methods of cyber resilience empowered by ESS. Furthermore, we propose that China should accelerate innovation to offset the combined effects of cyber resiliency engineering in developed countries, introduce a cyber resilience policy and law system with Chinese characteristics, establish corresponding regulatory systems to clarify the network security responsibilities, establish a quantifiable, verifiable, and credible testing and evaluation system, and boost the holistic implementation of cyber resilience with a multi-pronged approach including financial marketization, hoping to ystematically enhance the cyber resilience and strength of China.

To address the serious imbalance between the supply and demand of the cybersecurity workforce, this paper proposes to embrace the latest trend of a fundamental shift in the “underlying dynamics of the digital ecosystem”, focusing on a shared liability for cybersecurity between the application side and the manufacturing side. Assuming that product providers shall take more responsibility by implementing secure defaults, this paper explores the establishment of an S&S talent cultivation system to strike the right balance of cybersecurity liabilities by nurturing more responsible developers. This paper proposes a Knowledge, Skill, and Awareness (KSA) model for Security and Safety (S&S) talent cultivation, proves the feasibility of this model by analyzing the theoretical, disciplinary, methodological, practical, and societal foundations of S&S talent cultivation. Additionally, this paper proposes principles and strategies for building a S&S talent cultivation system based on its unique characteristics and patterns. It gives a talent cultivation scheme, supported by an “Independent Knowledge System, Education and Cultivation System, Practice and Training system, Evaluation and Certification system, and Awareness Popularization System”. Finally, this paper puts forward a proposal for coordinating efforts and adopting multiple measures to accelerate the cultivation of S&S talents.

The ever-increasing demand for new businesses and the continuous development of the Internet economy have increasingly demanded network communications and service capabilities, and the infrastructure and the deriving technology system of the existing network still face a series of major challenges. New network architectures and key technologies have become the core of a new round of technological revolution and industrial upgrading in the world. Therefore, studying the strategic conception and development paths of new network technology innovation becomes an urgent need for China. In this article, we analyze the challenges faced by the current network technology, discuss the development status of new network fields in China and abroad, and summarize the development trend of new network technologies. Subsequently, we summarize the gaps and development goals of China in the new network field. Finally we propose the key technologies for the new network development in China, including new network architecture, network fulldimension definable technology, polymorphic addressing and routing technology, network intelligence technology, and endogenous security structure. From the aspect of technology roadmap, we suggest that an open, integrated, and secure new architecture should be established to build a new network environment that is intelligent, diversified, personalized, robust, and efficient. From the aspect of national policy, we suggest that support policies should be formulated regarding technology research and development, industrial ecology construction, and market access.

In this paper, we propose a conjecture that endogenous security without any prior knowledge is similar to perfect secrecy without any prior knowledge. To prove the conjecture, we first establish a cryptography model of instinct function security to transform the security problem in the network domain into an encryption problem in the cryptographic domain. Then, we inherit and apply the established ideas and means of Perfect Secrecy, and propose the concept, definition and corollaries of the perfect instinct function security (PIFS) corresponding to Perfect Secrecy. Furthermore, we take the DHR system as a concrete implementation of PIFS and propose the DHR Perfect Security Theorem corresponding to Shannon’s Perfect Secrecy Theorem. Finally, we prove that the DHR satisfying the “One-Time Reconstruction” constraint is the sufficient and necessary condition to achieve perfect security. This means that the existence of PIFS is also proven. The analysis shows that any reconfigurable system can be encrypted by its construct and that the PIFS converts the one-way transparent superiority of the attacker into a double-blind problem for both the attacker and the defender, which leads to that the attacker is impossible to obtain useful construction information from the attacks and unable to find a better way than blind trial-and-error or brute-force attacks. Since the attackers are required to have the new powerful ability to crack the structure cryptogram, the threshold of cyber security is raised to at least the same level as cryptogram deciphering, thereafter the ubiquitous cyber threats are destined to be significantly reduced.

The common endogenous security problems in cyberspace and related attack threats have posed subversive challenges to conventional theories and methods of functional safety. In the current design of the cyber physical system (CPS), functional safety and cyber security are increasingly intertwined and inseparable, which evolve into the generalized functional safety (S&S) problem. The conventional reliability and cybersecurity technologies are unable to provide security assurance with quantifiable design and verification metrics in response to the cyberattacks in hardware and software with common endogenous security problems, and the functional safety of CPS facilities or device has become a frightening ghost. The dynamic heterogeneity redundancy (DHR) architecture and coding channel theory (CCT) proposed by the cyberspace endogenous security paradigm could handle random failures and uncertain network attacks in an integrated manner, and its generalized robust control mechanism can solve the universal problem of quantitative design for functional safety under probability or improbability perturbation. As a generalized functional safety enabling structure, DHR opens up a new direction to solve the common endogenous security problems in the cross-disciplinary fields of cyberspace.

Highlights Basalt fibers (BF) are widely used in shipbuilding due to their excellent corrosion resistance. However, basalt fibers do not possess good electromagnetic wave absorption properties, failing to meet the stealth performance requirements of ships. Therefore, this study focuses on basalt fiber composite materials, modifying the matrix by adding different amounts of carbon nanotubes (CNTs). Carbon nanotube‐basalt fiber‐epoxy resin absorptive composite materials are prepared using Vacuum Assisted Resin Transfer Molding (VARTM) technique to investigate the influence of CNT content on the materials. Samples with added CNTs can effectively absorb electromagnetic waves in the low‐frequency range, reducing surface reflectivity. In the high‐frequency range, the impedance matching value of the samples initially increases slowly. When the CNT content reaches 1.5 wt%, at a thickness of 2.5 mm and a frequency of 9.6 GHz, the minimum reflection loss of the sample is −14.40 dB, with an effective absorption bandwidth of 0.7 GHz. Also, CNTs can enhance the mechanical properties of composite materials. With increasing CNT content, both the bending strength and tensile strength of the composite materials are improved. When the CNT content reaches 1.5 wt%, the average tensile fracture strength of the material increases by 21%, and the bending strength increases by 9%. Enhanced low‐frequency electromagnetic wave absorption from CNTs and reduced polarization. Improved impedance matching and attenuation at high frequencies with CNTs. Significant enhancement in flexural and tensile strength due to CNTs and basalt fibers. [ABSTRACT FROM AUTHOR]

Carbon fiber‐reinforced composite materials exhibit excellent mechanical and electromagnetic shielding capabilities. However, they have some drawbacks, such as high cost and significant reflection losses. In order to address these shortcomings, this study set out to design a sandwich‐structured composite material and produce a composite material designed for electromagnetic shielding using Vacuum Assisted Resin Transfer Molding (VARTM) technology. This composite material promotes the "absorption‐reflection‐reabsorption" process of electromagnetic waves, significantly enhancing its shielding effectiveness, achieving up to 59.4 dB of shielding effect in the 8.2–12.4 GHz (X‐band) range. The study also employed carbon nanotubes (CNTs) matrix doping to modify the composite material, significantly reducing reflection losses. When the amount of carbon nanotubes added reaches 0.6 wt%, the overall SE can be increased by 18%. Additionally, the introduction of CNTs significantly improves the flexural strength and tensile strength of the composite material; at a 0.6 wt% CNT content, the average tensile strength increased from 526.4 to 600.9 MPa, indicating good interfacial interactions between CNTs and epoxy resin. This work provides valuable insights for the preparation of high‐performance electromagnetic shielding materials, with profound theoretical and practical significance. Highlights: Observations through SEM and CT scanning techniques reveal that Vacuum Assisted Resin Transfer Molding (VARTM) technology facilitates strong interlayer bonding between carbon fibers, glass fibers, and copper wires, alongside effective epoxy resin adhesion, thus enhancing the mechanical properties.The sandwich structure's impedance mismatch characteristic facilitates an efficient "absorption‐reflection‐reabsorption" process of electromagnetic waves. Additionally, the incorporation of Carbon Nanotubes (CNTs) enhances the absorption mechanism, reducing reflection losses.Incorporating CNTs further boosts both flexural and tensile strengths, attributed to improved interfacial interactions inhibiting crack formation. [ABSTRACT FROM AUTHOR]

With the widespread adoption of electronic technology, electromagnetic (EM) interference has become increasingly severe, adversely affecting the normal operation of electronic systems and posing significant threats to human health. EM shielding materials can effectively suppress various EM waves and EM interference generated through space by improving the EM compatibility of electronic systems and electronic devices. Recently, fiber-structure materials have been widely used for EM shielding due to their softness, thinness, and superior shielding efficiency. Therefore, this paper focused on fiber-based EM shielding materials, discussed the basic principles of EM shielding, the types of EM shielding fibers, the efficiency factors of EM shielding fabrics, and presented prospects for the future development of such materials. [ABSTRACT FROM AUTHOR]

To investigate the damage evolution and failure mechanisms of fiber-reinforced composite materials under complex conditions, this study conducted in situ X-ray computed tomography (CT) compression and tensile tests on plain weave two-dimensional woven SiC/SiC composite materials. The obtained CT in situ image data captured the behavior of materials during loading and after failure. Using the image reconstruction of CT data, the actual microstructure and damage evolution of the material under six consecutive loading levels were accurately revealed. Three-dimensional visualization models of the composite material were established using image processing software to analyze the damage evolution under compression and tension, and the failure mechanisms were compared. The results showed that the compression and tension failure mechanisms of SiC/SiC composite materials were similar, with the transverse cracking of the matrix being the first mode of damage, followed by delamination between layers and longitudinal matrix cracking of fiber bundles. Specifically, in terms of compression failure, the strength of the fiber bundle itself has a greater influence, and fiber fracture is the main cause of ultimate material failure. On the other hand, the primary cause of tensile failure is the presence of porosity defects generated during material fabrication. Consequently, the tensile material fails earlier and can withstand lower loads. [ABSTRACT FROM AUTHOR]