Hasil untuk "Nuclear engineering. Atomic power"

D. Marzullo, A. Clagnan, V.G. Belardi et al.

In the context of EUROfusion activities for the development of the DEMO reactor design, the divertor configuration is a major challenge. The current conceptual divertor design is based on the use of EUROFER97 for the divertor cassette body, while tungsten monoblocks bonded to CuCrZr pipes are used for plasma-facing targets. The evaluations developed to identify the best water coolant thermal–hydraulic conditions avoiding material embrittlement (for EUROFER 97) and softening/hardening (for copper alloy pipes) led to the identification of a new divertor baseline solution, based on the new cooling water operating conditions, named Divertor Single Null High-Temperature (SNHT). Such conditions require water at relatively high temperature (295 °C) and pressure (15.5 MPa), posing new challenging issues related to the general layout of the divertor cassette, its structural robustness and the manufacturing technologies.This work presents a comparative assessment between two different solutions proposed for the design and manufacturing of the divertor cassette body. A preliminary structural assessment and technological parameters are considered, as well as shielding and thermo-hydraulic performances.

Geunhyeong Lee

Electromagnetic pumps offer advantages in handling high-temperature or corrosive fluids by generating flow through Lorentz forces rather than mechanical impellers. However, direct current electromagnetic pumps typically require large currents, resulting in increased manufacturing costs due to thicker copper wires. This study proposes a novel direct current electromagnetic pump for metal additive manufacturing, potentially suitable for advanced Small Modular Reactors cooled by liquid sodium and liquid-metal charge stripper systems used in accelerators. Permanent magnets arranged in opposing directions generate concentrated magnetic flux around constrained flow paths, thereby producing multiple Lorentz forces and reducing the required input current. Numerical simulations demonstrate that the proposed design achieves a developed pressure of 10.5 bar at a significantly reduced current of 330 A, corresponding to a 52 % reduction in current compared to conventional helical-type pumps operating under similar conditions. Additionally, the new pump geometry simplifies fabrication by eliminating brazed joints and enabling a more compact design. These results indicate that 3D-printable electromagnetic pumps provide improvements in performance and ease of fabrication for high-pressure applications.

Yu.A. Zadneprovskiy, V. Bilous, V. Goltvyanytsya et al.

The elemental composition, mechanical properties and structure of Ti-Cr-N coatings deposited in a wide range of nitrogen pressures from unfiltered and filtered vacuum arc plasma flows from Ti-Cr alloy cathodes containing 23 and 32 wt.% Cr have been investigated. It was found that for different deposition modes, the dependence of the Cr content in the coatings on the nitrogen pressure has a minimum near 1·10-3 Torr, which correlates with the maximum hardness Hμ. When plasma filtration or a cathode with a lower Cr content is used, the hardness maximum shifts to lower nitrogen pressures. The mechanisms that determine the elemental composition of the coatings are discussed. In the coatings deposited at a pressure of 9·10–4…5·10–3 Torr, the main phase is a nanocrystalline cubic solid solution of (Ti,Cr)N with a NaCl-type structure. Increasing the chromium content in the cathode contributes to the formation of an amorphous crystalline structure. Filtration effectively separates the droplet component from the plasma stream and produces coatings with reduced surface roughness. Nanostructured Ti-Cr-N coatings with high mechanical properties (Hμ ~ 35 GPa) containing ~ 20 wt.% Cr, which can be used to protect structural materials in power engineering and other nuclear industries.

Farrukh Jamal, Sana Kanwal, Shakaiba Shafiq et al.

Modeling lifespan data with probability distributions is essential for decision-making in biomedical and health fields. This research introduces the New Extended Exponentiated Burr XII (NEEBXII) distribution, developed using a parameter induction technique to enhance flexibility in representing diverse data types across multiple domains. The methodology involves constructing the mathematical framework of the NEEBXII distribution, detailing key components such as order statistics, the quantile function, and moments. We employ three distinct methods for parameter estimation, rigorously evaluating their efficiency and robustness. Density function plots illustrate the NEEBXII distribution’s versatility, demonstrating various forms, including right- and left-skewed behaviors, while hazard rate function plots reveal both ascending and descending characteristics. To validate the practical applicability of the proposed model, we apply actuarial measures such as value-at-risk, expected shortfall, and tail variance. Empirical analysis using insurance claims and reliability datasets demonstrates that the NEEBXII distribution consistently outperforms existing alternatives, highlighting its robustness and effectiveness in real-world applications.

HAN Yuhang, ZHANG Jingwei, XU Haitian, HE Jiaqi, WEI Xinyu

With the rapid development of space exploration technology and expanding space application demands, major global powers have initiated key technological breakthroughs, particularly for critical enabling technologies such as space power systems. Conventional space power devices, including solar photovoltaic and chemical power sources, fail to meet the new requirements of modern space exploration. Space nuclear power system (SNPS), characterized by high power density and minimal susceptibility to external environmental factors, have gradually become the primary energy solution for future space missions. Precise load-following capability and robust anti-interference performance are essential for SNPS operation in complex and dynamic space environments. While simulation modeling and thermodynamic analysis of Stirling cycle-based SNPS have been well-established, research on control strategies for such systems is still limited. The PID control principle is a widely adopted control method featuring simple structure and high stability. Therefore, this paper investigated control strategies for Stirling cycle-based SNPS. A thermodynamic model of SNPS was first developed, comprising a lithium-cooled fast reactor (LFR), Stirling generator, radiation radiator, and connecting pipelines. Based on the system architecture, the mathematical-physical model integrated three fundamental equations: point-reactor neutron kinetics equations (describing fission chain reactions), core heat conduction equations (governing thermal behavior) and Stirling generator dynamics equations (characterizing power conversion). Simulation modeling was conducted on the MATLAB/Simulink platform, with steady-state and transient validations performed to verify model accuracy. Four PID control strategies were designed, including electric power deviation control (EPDC), coolant average temperature deviation control (CATDC), reactor power deviation control (RPDC) and three-channel control (TCC). Controller parameters were tuned using the trial-and-error method. For performance evaluation, three operating conditions were simulated, including 100%FP to 90%FP load step change, −100 pcm reactivity disturbance, and −0.5 kg/s coolant flow rate disturbance. For the first one, EPDC achieves the fastest parameter regulation with minimal settling time (26.43 s) due to its direct responsiveness to load changes. However, RPDC demonstrates superior performance for scenarios prioritizing rapid reactor power response (zero overshoot, 3.94 s settling time). Under reactivity and coolant flow rate disturbance, RPDC exhibits the smallest fluctuation amplitudes (159.2 W power variation under −100 pcm disturbance; 55.22 W variation under −0.5 kg/s flow rate disturbance) and fastest stabilization, attributed to its high sensitivity to primary loop parameter variations. This study systematically evaluates PID-based control strategies for Stirling cycle-based SNPS through comprehensive modeling and multi-scenario validation. The findings provide quantitative guidance for control strategy selection under different operational priorities, with EPDC recommended for load-following dominance and RPDC preferred for primary loop stability. The developed simulation framework and parameter tuning methodology offer valuable references for advancing control systems in next-generation space power applications.

ZHOU Peide, HU Yun, XUE Xiuli, SU Xiping, HUO Xingkai, LIN Chao, CHEN Qidong, SONG Yingyun, WANG Zhenzhong

The sodium-cooled fast reactor (SFR) has the functions of nuclear fuel breeding and transmutation of long-lived minor actinides, and it is one of the main recommended reactor types for the fourth-generation nuclear energy systems. The realization of the functions and performance advantages of the SFR mainly depends on the core design. The SFR has already shown a trend towards large-scale and commercial application. Based on the analysis of the connotation of the SFR core design and existing design practices, this paper focused on improving the economy, safety, and sustainability of the SFR, and studied and proposed directions and measures for core design optimization. These include: targeting the increase of fuel burnup limit, the average discharge burnup of fuel, and the flattening of core coolant outlet temperature to enhance economy; targeting the optimization of negative reactivity feedback effects, the improvement of reactivity control performance, and the optimization of natural circulation design to enhance safety; and targeting the improvement of nuclear fuel breeding and the transmutation capability of long-lived minor actinides to enhance sustainability. The proposed directions and measures for core design optimization can serve as the goals and main content for the research and development of SFR core design.

Lekshmi Murali Rani

The study of behavioral and social dimensions of software engineering (SE) tasks characterizes behavioral software engineering (BSE);however, the increasing significance of human-AI collaboration (HAIC) brings new directions in BSE by presenting new challenges and opportunities. This PhD research focuses on decision-making (DM) for SE tasks and collaboration within human-AI teams, aiming to promote responsible software engineering through a cognitive partnership between humans and AI. The goal of the research is to identify the challenges and nuances in HAIC from a cognitive perspective, design and optimize collaboration/partnership (human-AI team) that enhance collective intelligence and promote better, responsible DM in SE through human-centered approaches. The research addresses HAIC and its impact on individual, team, and organizational level aspects of BSE.

Nataliia Rozinkevych

The effects of humankind during the Capitalocene period caused planetary changes that resulted in the devastation and destruction of the Earth. The nuclear tragedy at the Chornobyl NPP on April 26, 1986, should serve as a constant reminder to society as it provided an example of dysfunctional totalitarian management.The topic of Chornobyl has become socially tiresome in recent years due to the trivialization of this large-scale anthropogenic, ecological, economic, and humanitarian disaster. The image of Ukraine as a hazard area has gradually been replaced in world consciousness. When Russia, the aggressor country, started to intimidate the world with nuclear and thermonuclear weapons and to take the nuclear power plants in Ukraine under fire, the danger of radioactive materials came up once again. Phosphorous ammunition used in Ukraine in 2022 demonstrates that the terrorist state is capable of anything. Scientists also relate to earthquake motions that occurred in Turkey in February 2023 and Japan in January 2024, with the displacement of continental plates of the Earth’s crust resulting from missile attacks at the surface of the Earth.In the 21st century, there was a need to reconsider and refresh memories as well as to reread the works under a new perspective to draw attention to crimes against the safety of humanity and the environment, as well as to popularize, preserve and pass historical knowledge to future generations to protect them from traumatic experiences and self-destruction.The article aims to look at the postcolonial environment in contemporary literature of fact through the spectacle of ecocritical discourse via reading the works on the Chornobyl disaster. The objects of the study are Galia Ackerman’s work “Crossing Chornobyl”, the documentary and publicist chapter “Chornobyl Scenario” from the novel “Non-format Journalism” by Hryhorii Krymchuk, Volodymyr Shovkoshytnyi’s semidocumentary short story “Chornobyl: I Saw It”, the chapter “Elon Musk, “Tesla”, and Nuclear Power Engineering” from Maks Kidruk’s popular scientific book “Theory of Improbability”, Oleksii Radynskyi’s literary report “Chornobyl Is Ukraine”, and Markiian Kamysh’s travelogue “Stalking the Atomic City”.Study methods include principles of science, objectivity, and source verification. General scientific and special scientific research methods used in the study are a descriptive method for synthesizing and systematizing selected material; comparative and typological methods involving the elements of cultural, comparative, and narrative studies to compare the ways various authors have covered the Chornobyl topic; an ecocritical method that has made it possible to apply naturecentric approach to conceptualizing interaction between a human and nature to develop eco-conscious society; a postcolonial method aimed at conceptualizing the consequences of colonial rule via non-fiction text.

Shi-ping WEI, Yuan HU

Fusion energy is a kind of clean energy with very low pollution for large-scale production, and the current mainstream solution is magnetic confinement nuclear fusion, which is considered to be the most promising way to achieve commercial fusion power generation. Radioactive tritium, as one of the fuels of fusion reactors, is easily permeable in stainless steel structural material, which causes a huge waste of scarce fuel and also brings huge cost to radiation protection. It is important to study the tritium permeation behaviors in stainless steel for the tritium self-sufficiency and safe operation of fusion reactor. They are closely related to the structural safety of fusion reactor components, tritium extraction of blankets, fuel cycle of tritium plant as well as the protection of the public and environment. This paper introduces the mechanism of tritium permeation in stainless steel and main methods and research progress of tritium penetration behavior simulation both domestically and internationally, analyzes the existing problems in the simulation of tritium permeation behaviors, and looks forward to the new research direction. High-temperature gas phase permeation(GDP), thermal desorption spectrum(TDS) and chemical etching methods are generally used to study the adsorption, dissociation, diffusion and desorption of hydrogen isotopes in stainless steel from the experimental aspect. It is pointed out that there are few experimental studies on direct use of tritium, which leads to the great uncertainty of the corresponding tritium permeation data. At present, the experimental research mainly focuses on the tritium permeability parameters of stainless steel and the degree of related influence factors, but no systematic theoretical system has been formed. The tritium permeation behaviors in stainless steel under the radiation of fusion neutron also need to be further studied, and explain the effects of radiation damage, surface stress, defects, dislocations, and impurity elements on tritium adsorption, tritium diffusion, tritium retention, and tritium desorption. The classical tritium permeation model and a single simulation method cannot accurately describe the tritium permeation behaviors. There are still many unsolved problems and even disputes about the theoretical models. The single tritium permeation simulation approach has specific disadvantages. An organic combination of existing tritium permeation simulation methods such as empirical formula solution, system dynamics(SD) simulation, computational fluid dynamics(CFD) simulation and first principles calculation is proposed to achieve multi-scale from zero dimension to three dimension and multi-physical coupling accurate simulation. This work will provide valuable theoretical guidance and technical solutions for accurate tritium transport simulation in stainless steel.

Moonhyung Cho, Hyeongjin Kim

During outages at nuclear power plants, much more care for radiation workers against internal exposure should be ensured given that more hot particles exist relative to the amount during normal operation. If fuel-type hot particles (FTHP) are inhaled, they can cause more severe health risks compared to activation-type hot particles (ATHP), which contain 60Co, due to the alpha-emitting nuclides within FTHPs. The activities of difficult-to-measure nuclides within FTHPs inhaled by workers are inferred by the age-dating technique using a141Ce/144Ce ratio as measured by whole-body counters. However, this method may be limited to outages that last for only a few months due to the short half-life (32.5 days) of 141Ce. We studied the feasibility of utilizing 241Am, a nuclide with a long half-life of 432.6 years, as an alternative to 141Ce. Additionally, we improved the performance of a stand-type whole-body counter for low-energy gamma spectroscopy to meet the criterion (RMSE ≤0.25) specified in ANSI/HPS N13.30–2011 by employing an artificial neural network (ANN). This study can contribute to more rapid and accurate internal dose assessments for workers who have inhaled FTHPs during long-term outages at nuclear power plants.

Sachinth Viththarachchige, Demy Alexander, Sarangan Rajendran et al.

With the increasing frequency of high impact low probability events, electricity markets are experiencing significant price spikes more often. This paper proposes a novel social equity driven optimal power flow framework to mitigate the adverse effects of price events that lead to such price spikes. The framework integrates social welfare optimization with socioeconomic considerations by including a socioeconomic score that quantifies the energy burden and socioeconomic status of consumers. By incorporating both supply cost and consumer satisfaction, the model aims to achieve a balanced and fair distribution of resources during price events, while considering resource scarcity and possible load curtailment. The proposed framework is tested for convergence on modified versions of the PJM 5-bus system and IEEE 24-bus reliability test system, discussing its potential effectiveness in enhancing social equity and optimizing power flow under system security constraints. Sensitivity analysis further highlights the impact of socioeconomic score on social welfare, providing insights for future improvements.

C. Danson, L. Gizzi

Abstract On behalf of all at High Power Laser Science and Engineering we would like to congratulate the team at Lawrence Livermore National Laboratory (LLNL) on demonstrating fusion ignition at the National Ignition Facility. This major scientific achievement was realized on the 5 December 2022 at the LLNL and announced at a press briefing on the 13 December 2022 by the United States Department of Energy’s National Nuclear Security Administration. This was a historic milestone and the culmination of decades of effort.

Yajie Huang, Donglai Zhang, Tao Wang et al.

Air-cooled power can rapidly dissipate heat, eliminate more heat, and prevent equipment from overheating. It is widely applied in the field of engineering. Capacitors have the highest failure rate of the overall power supply. This article presents a noninvasive method for estimating the temperature of electrolytic capacitors in air-cooled power supplies. The technology is suitable for power sources that cannot be turned off for intrusive detection of the temperature of electrolytic capacitors, such as nuclear power supplies. The proposed method makes it possible to measure the ambient temperature of electrolytic capacitors in nuclear power supplies. Therefore, the safety performance of nuclear power is greatly improved. It is sufficient to measure the output voltage, output current, air inlet temperature, air outlet temperature, and fan speed. This method only needs to build a model based on historical data or data from the same series of power supplies and then input these parameters into the trained neural network model. The ambient temperature of the capacitor can be estimated by using this model. Finally, the prediction results of four neural networks are compared using a 3-kW air-cooled power supply as an example, and the applicability of the neural network technique is demonstrated.

Ruizhi Shao, Liangzhi Cao, Yunzhao Li et al.

Self-powered neutron detector (SPND) plays a vital role in the Gen-III pressurized water reactors (PWR). When electrons are trapped in the insulator of SPND, an electric field can be generated in the insulator that affects the response current. It is called the “space charge effect.” To analyze this effect quantitatively, a novel method based on the electric current continuity equation was proposed to simulate the variation of the electric field in the insulator: 1) the time-dependent response current and the recursive equation for the electric field were derived; 2) an SPND simulation code system was developed and validated. In the code system, the Bamboo-Lattice code and the Nuclear Engineering Computational Physics (NECP)-MCX code were used to calculate the neutron-photon spectrum near the SPND, while the neutron-photon-electron transport calculation was performed in Geant4; 3) the calculated sensitivities were verified by measurements on various SPNDs, among which good agreements were found; 4) the electric field and electric potential distribution of the V-SPND in the AP1000 core were simulated with the formation process and the equilibrium duration illustrated. The components of the response current were compared with the measurements. The error of the response current ranges from −6.48% to 6.2%, and the difference of the prompt current ratio ranges from 1.6% to 3.4%; and 5) the influence of neutron flux, electrical conductivity, permittivity, and time step on the electric field was analyzed, revealing that both neutron flux and electrical conductivity significantly influence the response current and electric field, whereas the influence of permittivity and time step is negligible.

V. Merkulov, N. Didenko, D. Skripnuk et al.

Small modular reactor technologies and social, economic, and technological aspects of their application in the Russian Arctic are considered in the article. An overview of the key factors influencing an implementation of small modular reactor plants in remote regions with a decentralized power grid is presented. The main directions of small modular reactor design activities of the key Russian centers of atomic research and development are given. An overview of current Russian small modular reactor technologies including pressurized water reactors, boiling water reactors, reactors installed on floating nuclear power plants, high-temperature gas-cooled reactors, and liquid metal cooled reactor is conducted. Economic, social, ecological, and digital aspects of applications of small modular reactor in the Russian Arctic are considered. A detailed survey of areas of small modular reactor application including extractive, processing, industrial energy-intensive facilities, and power and heat supply of cities is also given. The importance of digital twins of small modular as an essential element in the development and maintenance of complex engineering products and industrial facilities throughout the entire life cycle is discussed in the article. Conclusions about key advantages and prospects of an application of small modular reactors in the Russian Arctic are made.

Margot Hurlbert, Larissa Shasko, Jose Condor et al.

People’s affective response in relation to radiation is important in their risk perceptions of low-dose radiation (LDR), medical interventions involving LDR, and acceptance of nuclear power production. Risk perception studies generally relate to the health field of LDR or nuclear power. This study combines risk perceptions and acceptance of both. While acceptance by those with an understanding of radiation is demonstrated in focus groups, survey results disproved this correlation. Emotional response to the word radiation together with greater perceptions of risk to X-rays, were predictors of acceptance of nuclear power production.

Vishnu Ganesh, Daniel Dorow-Gerspach, Martin Bram et al.

Functionally graded tungsten/steel composites are attractive to be used as an interlayer to join tungsten (W) and steel for the first wall of future fusion reactor to reduce the thermally induced stresses arising from the different coefficient of thermal expansion (CTE) of W and steel. W/steel composites, with three W contents: 25, 50 and 75 vol% W, will serve as individual sublayers of this functionally graded material. Therefore, the present work exploits an emerging sintering technique, field-assisted sintering technology, to produce these composites. Firstly, a systematic parameter study was conducted aiming to reduce the residual porosity to a minimum while keeping the formation of intermetallic phases at the W/steel interface at a low level. The optimized composites 25, 50 and 75 vol% W achieved a relative density of 99%, 99% and 96%, respectively. Secondly, mechanical tests at elevated temperatures reveal that these composites are ductile above 300 °C, which is the minimum operating temperature of the first wall. Lastly, the measured CTE, specific heat capacity and thermal conductivity were consistent with the theoretically expected values.

N. Asakura, K. Hoshino, S. Kakudate et al.

The power exhaust concept and an appropriate divertor design are common critical issues for tokamak DEMO design activities which have been carried out in Europe, Japan, China, Korea and the USA. Conventional divertor concepts and power exhaust studies for recent DEMO designs (Pfusion = 1 – 2 GW, Rp = 7 – 9 m) are reviewed from the viewpoints of the plasma physics issues and the divertor engineering design. Radiative cooling is a common approach for the power fusion scenario. Requirements on the main plasma radiation fraction (fradmain = Pradmain/Pheat) and the plasma performance constrain the divertor design concept. Different challenges contribute to optimizing the future DEMO designs: for example, (i) increasing the main plasma radiation fraction for ITER-level Psep/Rp designs and simplifying the divertor geometry, and (ii) extending ITER divertor geometry with increasing divertor radiation (Praddiv) for larger Psep/Rp ≥ 25MWm−1 designs. Power exhaust simulations with large Psep = 150 – 300 MW have been performed using integrated divertor codes considering an ITER-based divertor geometry with longer leg length (1.6 – 1.7 m), as in a common baseline design. Geometry effects (ITER like geometry or more open one without baffle) on the plasma detachment profile and the required divertor radiation fraction (fraddiv = Praddiv/Psep) were key aspects of these studies. All simulations showed that the divertor plasma detachment were extended widely across the target plate with a reduction in the peak heat load of qtarget ≤ 10 MWm−2 for the large fraddiv = 0.7 – 0.8, while the peak qtarget location and value were noticeably different in the partially detached divertor. Simulation results also demonstrated that radial diffusion coefficients of the heat and particle fluxes were critical parameters for DEMO divertor design, and that effects of plasma drifts on outboard-enhanced asymmetry of the heat flux, suggested the need for longer divertor leg to ensure the existence of a detached divertor operation with qtarget ≤ 10 MWm−2.Integrated design of the water cooled divertor target, cassette body (CB) and cooling pipe routing has been developed for each DEMO concept, based on the ITER-like tungsten monoblock (W-MB) with Cu-alloy cooling pipes. Engineering design adequate under higher neutron irradiation condition was required. Therefore, inlet coolant temperature (Tcool) was increased. In current designs, it still shows a large potential variation between 70 °C and 200 °C. The influence of thermal softening on the Cu-alloy (CuCrZr) pipe was fostered near the strike-point when the high qtarget of ∼10 MWm−2 was studied. Improved technologies for high heat flux components based on the ITER W-MB unit have been developed for EU-DEMO. Different coolant conditions (low- and high-Tcool) were provided for Cu-alloy and reduced activation ferritic martensitic (RAFM) steel heat sink units, respectively. The high-Tcool coolant was also considered for the CB and supporting structures. Appropriate conditions for the high-Tcool coolant, i.e. 180 °C/ 5 MPa (EU-DEMO) and 290 °C/ 15 MPa (JA-DEMO, CFETR and K-DEMO), will be determined in the future optimizations of the divertor and DEMO design.

Erfu Guo, Vishal Jagota, M. Makhatha et al.

Abstract To solve the problems of large mechanical powertrain such as complex structure, serious accident, strong nonlinear characteristics of running state, bad operating environment, non-Gaussian noise, and various uncertain factors, it is difficult to make an accurate fault diagnosis. This paper proposes a method for dealing with nonlinear characteristics using nuclear waves, as well as a system, deeply conducted nuclear base fault feature extraction, classification, and decision making, such as nuclear base state trend prediction technology research, focusing on exploring and improving the accuracy of fault diagnosis under nonlinear conditions, technical method, and way to state prediction accuracy. It offers effective technical assistance for the advancement and use of mechanical power train monitoring and diagnosis technology. A fault detection method based on kernel method is proposed. Based on the characteristics of this method in dealing with nonlinear problems, the research on kernel feature extraction, kernel fault classification and decision making, and kernel state trend prediction are carried out systematically. The experimental results show that the simulation analysis of typical chaotic time series prediction and the application of the operation state prediction of a certain ship main steam turbine unit have achieved good results, among which the average relative error of the single-step prediction of the unit state is 1.7881%, and the average relative error of the 30-step prediction is 3.3983%. Proved that the nuclear methods systematically applied to mechanical power transmission system fault diagnosis and state prediction, effectively enhancing some traditional methods and techniques dealing with nonlinear feature extraction, the nonlinear prediction capability for fault identification, and nonlinear state, to deal with nonlinear fault diagnosis problems of engineering practice, a large number of explored effective solution.

M. Zuo

With the development of new technology, engineering systems are becoming more complex in structure and possessing more advanced functions. Customers are setting higher quality requirements for new products. Reliability must be considered in all aspects of the product life cycle. Inadequate reliability considerations may cause civil aviation disasters, nuclear power plant accidents, spacecraft launch failures, power system shutdowns, and other major accidents. Since the emergence of the reliability discipline in the 1950s, reliability theory has been developing rapidly, which has played an irreplaceable role in promoting the progress of major industries such as aviation, aerospace, and nuclear energy. It has also greatly improved the quality of daily necessities such as computers, appliances, and automobiles. The capability of manufacturing high-end equipment with high reliability and long life has become an important strategic indicator of a country’s global strength and competitiveness. In recent years, due to climate change and ecosystem degradation, extreme weather has become more frequent all over the world. Under unusual conditions such as extreme weather and external attacks, it is no longer possible for sophisticated engineering systems to meet their performance requirements if only traditional reliability indexes are used, and resilience has become an important index to consider for system design, evaluation, and optimization. To respond to the increasingly complex international environment and diversified challenges, the US has been requiring military equipment systems to ensure functional stability under uncertain and diverse combat conditions, to have the ability to quickly restore functions after experiencing damage, and to adapt rapidly to changing environmental conditions. Around 2010, the US Department of Defense introduced the concept of “resilience” into weapon and equipment development and established the Engineering Resilience System Project. This project formulated a long-term strategy to continuously improve the resilience of weapon equipment through its design, improvement, manufacturing, and deployment. Resilience has become a new important guiding performance index throughout the entire lifecycle of weapon equipment in the US (Scott, 2012). Actually, resilience has become a key performance index of all critical systems including power grid, infrastructure, and communication systems.