摘要：
The emission of volatile organic compounds (VOCs) from asphalt during construction processes presents substantial risks to human health and the environment. To advance sustainable transportation development, this review offers a comprehensive study of the methods for characterization, release characteristics, influencing factors, release mechanisms, and environmental impacts of asphalt VOCs. At present, research has been conducted on characterization methods, component characteristics, influencing factors, and environmental and health risks. The findings indicate that gas chromatography-mass spectrometry is the most comprehensive method for characterizing asphalt VOCs. Asphalt VOCs mainly comprise alkanes, aromatics, and aliphatic hydrocarbons. Factors including the temperature, asphalt source, and ultraviolet radiation can all affect the release characteristics of asphalt VOCs. Elevated VOC levels contribute to the photochemical production of ozone and fine particulate matter, exacerbating air pollution and climate change. Additionally, specific asphalt VOCs, including benzene and polycyclic aromatic hydrocarbons, pose health risks to humans. While progress has been achieved in the current research, challenges persist in quantifying VOCs, assessing their environmental impacts and health risks, and implementing effective mitigation technologies. To address these challenges, future research should focus on establishing asphalt VOC fingerprints, quantitative methods, evaluation criteria, material innovation, optimization of construction processes, exposure assessment, and collaborative solution implementation.
摘要：
In this work, APBO and its typical organic matter (HAc, Phenol, Guaiacol) were used to pretreat wheat straw separately, and CFP characteristics of wheat straw before and after the pretreatment were investigated. Washing with four different solutions removed more than 95% of K(+ )and over 86% removal of Na+; the removal effect of APBO on Ca2+ and Mg2+ is more evident with more than 84%. Washing reduced AAEMs, thereby reducing acids and ketones and increasing sugars in the bio-oil. TGA demonstrated that different washing significantly increased wheat straw's maximum weight loss rate and overall weight loss rate. After the subsequent addition of HZSM-5 catalyzed pyrolysis, the level of oxygen-containing compounds in bio-oil was significantly reduced and the aromatic hydrocarbon level increased from 2.19% (R) to 14.89% (CR), 31.28% (APBO-CR), 25.9% (HAc-CR), 24.74% (Phenol-CR), 15.81% (Guaiacol-CR), and the highest selectivity was 54.57% for BTX (APBO-CR). The combined APBO washing and HZSM-5 is a potential technology for upgrading biomass and the liquid products of pyrolysis because it can effectively raise bio-oil quality.
摘要：
Transportation systems are critical lifelines and vulnerable to various disruptions, including unforeseen social events such as public health crises, and have far-reaching social impacts such as economic instability. This paper aims to determine the key factors influencing the severity of traffic accidents in four different stages during the pre- and the post Covid-19 pandemic in Illinois, USA. For this purpose, a Random Forest-based model is developed, which is combined with techniques of explainable machine learning. The results reveal that during the pandemic, human perceptual factors, notably increased air pressure, humidity and temperature, play an important role in accident severity. This suggests that alleviating driver anxiety, caused by these factors, may be more effective in curbing crash severity than conventional road condition improvements. Further analysis shows that the pandemic leads notable shifts in residents' daily travel time and accident-prone spatial segments, indicating the need for increased regulatory measures. Our findings provide new insights for policy makers seeking to improve transportation resilience during disruptive events.
摘要：
Fractional-order differentiation (FOD) can record information from the past, present, and future. Compared with integer-order systems, FOD systems have higher complexity and more accurate ability to describe the real world. In this paper, two types of fractional-order memristors are proposed and one type is proved to have extreme multistability, local activity, and non-volatility. By using memristors to simulate the autapse of a neuron and to describe the phenomenon of electromagnetic induction caused by electromagnetic radiation, we establish a new 5D FOD memristive HNN (FOMHNN). Through dynamic simulation, rich dynamic behaviors are found, such as hyperchaos, multiscroll, extreme multistability, and "overclocking" behavior caused by order reduction. To the best of our knowledge, this is the first time that such rich dynamic behaviors are found in FOMHNN simultaneously. Based on this FOMHNN, a very efficient and secure image encryption scheme is designed. Security analysis shows that the encrypted Lena image has extremely low adjacent pixel correlation and high randomness, with information entropy of 7.9995. Despite discarding diffusion and scrambling, it has excellent plaintext sensitivity, with NCPR = 99.6095% and UACI = 33.4671%. Finally, this paper implements the proposed FOMHNN and image encryption on field programmable gate array (FPGA). To our knowledge, the related work of fully hardware implementation of fractional-order neural networks and image encryption schemes based on this is rare.
关键词：
Reversible natural language watermarking;Sensitive information protection;Masked language model;Keyword extraction;Prediction error expansion;Lexical substitution
摘要：
Existing methods have evolved from using synonym substitution to incorporating arbitrary word substitution to achieve reversible natural language watermarking. However, a notable limitation is that they are prone to overlook the sensitivity of information associated with the original words, with a tendency to prefer non -sensitive words for substitution. As a result, a potential risk of sensitive information leakage contained in the original text is posed. Furthermore, while aiming for reversibility, the overall performance of the watermarking method may be inadvertently compromised. In response to the above problems, this paper puts forward a novel reversible natural language watermarking method that combines a Keyword Substitution scheme and a Prediction Error Expansion algorithm (KSPEE) to protect sensitive information, verify content integrity, protect copyright, and so on. Specifically, KSPEE leverages a keyword extraction algorithm to identify important content containing sensitive information in the original text, thereby determining the potential positions for watermark information embedding. Subsequently, a masked language model is utilized to predict appropriate substitution words based on the surrounding semantic information of the embedding position. In addition, the prediction error expansion algorithm is employed to select appropriate words for substituting the original keywords, ensuring the successful embedding of watermark information while maintaining the recoverability of the original keywords. By identifying keywords and substituting them, a suitable method of protecting the original sensitive information is provided. Extensive experiments demonstrate that, under the promise of semantic distortion and lossless restoration of the original content, the proposed method KSPEE achieves outstanding watermarked text quality. A higher watermark embedding rate is achieved and strong security is shown by KSPEE. More importantly, KSPEE effectively prevents the leakage of sensitive information.
期刊：
Journal of Materials Chemistry A,2024年12(1):277-285 ISSN：2050-7488
通讯作者：
Yang, J;Cao, PH
作者机构：
[Yang, J; Tang, Jingjing; Yang, Juan; Meng, Qi; Zhang, Guilin; Bai, Qixian] Cent South Univ, Sch Met & Environm, Changsha 410083, Peoples R China.;[Liu, Weiping; Lin, Wenjun; Yi, Pengfei] Zhuzhou Smelter Grp Co Ltd, Zhuzhou 412000, Peoples R China.;[Cao, Penghui] Changsha Univ Sci & Technol, Coll Energy & Power Engn, Changsha 410114, Peoples R China.
通讯机构：
[Yang, J ; Cao, PH ] C;Cent South Univ, Sch Met & Environm, Changsha 410083, Peoples R China.;Changsha Univ Sci & Technol, Coll Energy & Power Engn, Changsha 410114, Peoples R China.
摘要：
Aqueous zinc-ion batteries (AZIBs) are considered to be a green and safe energy storage system. However, electrolyte leakage, zinc dendrite growth and side reactions are still barriers to their practical application. A quasi-solid sodium alginate gel electrolyte (GE) was designed to alleviate these pain points. To further stabilize the water molecules in this GE and extend its application to subzero temperatures, a disaccharide called trehalose (TreH) was introduced as a multifunctional additive. The rational introduction of TreH notably improved the strength (186.6 kPa) of the sodium alginate GE while retaining a high ionic conductivity (22.4 mS cm-1) at 25 degrees C. The zinc-polyaniline full battery assembled with this composite GE exhibited a capacity retention of 70.4% after 500 cycles at 25 degrees C, and still delivered a reversible capacity of 120.6 mA h g-1 at -20 degrees C. These results show that the sodium alginate GE with trehalose as an additive has great potential for development in AZIBs. Sodium alginate was selected as a matrix and trehalose was employed as an additive to form a hydrogel electrolyte for Zn-ion batteries applied at low temperatures.
摘要：
In recent advancements, a novel strengthening approach employing engineered cementitious composites (ECC) and fibrereinforced polymer (FRP) materials has emerged. This method integrates ECC as the matrix, carbon fibre-reinforced polymer (CFRP) grid as the internal strengthening component, and epoxy resin for bonding the overlay to the concrete substrate. This study conducted tests on four reinforced concrete (RC) beams under a four-point load configuration. One beam served as an un-strengthened control specimen, while three were subjected to different shear strengthening methods: polymer-modified mortar (PMM), ECC, and CFRP grid-reinforced ECC matrix composites layer (FGREM). The investigation covered failure modes, load-deformation relationships, and load-strain relationships. Finite element (FE) analysis was employed to reproduce the test results. Key findings include the ability of ECC as a matrix to substantially reduce concentrated interfacial bond stresses, preventing debonding failure. The FGREM-strengthened specimen exhibited a failure mode characterized by side concrete cover separation, resulting in a notable 124% enhancement in shear resistance. The proposed FE model, incorporating interfacial behaviour, accurately simulated the performance of all specimens.
摘要：
Immobilizing enzyme to nano interfaces has demonstrated to be a favorable strategy for prompting the industrialized application of enzyme. Despite tremendous endeavor has been devoted to using gold nanoparticles (AuNPs) as conjugation matrix due to its fascinating physico-chemical properties, main-taining enzymatic activity while circumventing cumbersome modification remains a formidable chal-lenge. Herein, the freezing-directed conjugation of enzyme/nano interfaces was constructed without extra reagent. As the proof of concept, glucose oxidase (GOx) was chosen as model enzyme. The one-pot con-jugation process can be facilely completed at -20 degrees C under aqueous solution. Moreover, with the loading of GOx on AuNP at freezing, the enzyme exhibited superior catalytic activity and stability upon ther-mal and pH perturbation. The mechanism of boosted activity was then discussed in detail. It was found that higher loading density under freezing condition and more enzyme tending to bind AuNPs via Au-S bond were the main factors for the superior activity. More importantly, this methodology was universal and can also be applied to other enzyme which contains natural cysteine, such as horseradish peroxi-dase (HRP) and papain. This facile conjugation strategy accompanied by remarkable bioactivity expand the possibilities for enzymatic biosensing, microdevice and even drug delivery. (c) 2023 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.
关键词：
Water storage capacity;Dongting Lake;Hydrodynamic modeling;Multiple linear regression;Remote sensing
摘要：
Study region: Dongting Lake, China Study focus Water storage capacity (WSC) of a large lake system plays a crucial role in flood control decisionmaking during the flood season. Dongting Lake, located downstream of Three Gorges Dam, has a significant influence over flood control in the middle and lower reaches of the Yangtze River (MLYR). To have a better WSC estimation of Dongting Lake, a multiple linear regression model was developed based on hydrodynamic simulation data of the typical flood processes in the past 3 decades. New hydrological insights for the region The multiple linear regression (MLR) model is developed by integrating of hydrodynamic simulation. Also, the effect of the water level (WL) at Chenglingji station and the WL difference in the lake (Yangliutan-Chenglingji) were investigated. The model can accurately estimate the WSC of Dongting Lake with an R2 of 0.984. The observation indicates that the WL difference within the lake has a great influence on the WSC and the flood regulation capacity ability with the same WL at Chenglingji station. The results of the study can provide a real-time estimation of the WSC of Dongting Lake which can provide useful information for flood control management.
摘要：
Magnetosonic (MS) waves play a significant role in magnetospheric dynamics. They usually appear as electromagnetic fluctuations near the multiples of proton gyro-frequency. Recently, a distinct type of MS wave, quasi-electrostatic magnetosonic (QEMS) wave has been reported, of which only the electric field can be detected. Here we investigate the favorable generation conditions, spatial distribution, and frequency spectral features of the waves through a statistical study using Van Allen probes data. The results show that most (83%) of them are detected with a low plasma density n(e)<20 cm(-3), and the wave tends to be stronger in the lower density region. QEMS waves would also become stronger when the proton ring (10 keV) is more pronounced and the suprathermal (tens to hundreds of eV) proton population is larger. Most of the QEMS waves, especially the intense ones, are confined in the dayside equatorial region (|MLAT| < 3(degrees)). The wave frequencies are typically slightly below the multiples of proton gyro-frequency, and the wave amplitude gradually decreases with the increase of harmonic number. Our results further demonstrate that low plasma densities and abundant suprathermal protons are beneficial for intensifying QEMS waves and reveal the spatial distribution and frequency spectral characteristics of QEMS waves.
摘要：
In this study, a fast hybrid algorithm based on surrogate and theoretical models is proposed. It solves surrogate model failure with too many inputs to the system and improves the computational efficiency in random vibration analysis of train-bridge systems under crosswinds. First, the surrogate model to rapidly predict the wheel-rail force time history and the theoretical model (finite element model) of the bridge are established. Then, a large number of samples of fluctuating wind speeds and track irregularities are generated based on the Monte Carlo method. Next, the wheel-rail force and the dynamic response of the bridge are calculated using the surrogate and theoretical models, respectively, and the coupling of the train and bridge subsystems is realized through iteration. Finally, the random vibrations of the train-bridge system under crosswinds are analyzed based on the calculation results of all samples. The results of the hybrid algorithm agree well with those of the traditional calculation method. The maximum normalized mean square error (NMSE) is only 0.0105, and the computational efficiency of the hybrid algorithm is nearly 4 times higher than that of traditional calculation methods. When the train is in the midspan of the bridge, the bridge dynamic response has a large mean and standard deviation. Under crosswinds, wheels on the windward side determine the safe running of the entire train. Under the wind speed of 15 m/s and Chinese high-speed railway track irregularities, the train operation reliability on the bridge is 98 %.
期刊：
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing,2024年890:145889 ISSN：0921-5093
通讯作者：
Zhou, SF;Yang, H;Liu, YJ
作者机构：
[Yi, Yanliang; Li, Kunmao; Zhou, Shengfeng; Jin, Jianbo; Zhou, SF; Yang, Junjie] Jinan Univ, Inst Adv Wear & Corros Resistance & Funct Mat, Guangzhou 510632, Peoples R China.;[Yang, H; Yang, Huan] Shenzhen Technol Univ, Sino German Coll Intelligent Mfg, Shenzhen 518118, Peoples R China.;[Liu, Yujing] Changsha Univ Sci & Technol, Inst Met, Coll Mat Sci & Engn, 960,2 Sect,Wanjiali RD, Changsha 410004, Hunan, Peoples R China.;[Chen, Dongchu] Foshan Univ, Sch Mat Sci & Energy Engn, Foshan 52800, Guangdong, Peoples R China.;[Zhang, Wencai] Jinan Univ, Affiliated Hosp 1, Dept Orthoped, Guangzhou 510632, Peoples R China.
通讯机构：
[Yang, H ] S;[Liu, YJ ] C;[Zhou, SF ] J;Jinan Univ, Inst Adv Wear & Corros Resistance & Funct Mat, Guangzhou 510632, Peoples R China.;Shenzhen Technol Univ, Sino German Coll Intelligent Mfg, Shenzhen 518118, Peoples R China.
关键词：
Laser powder bed fusion (L-PBF);Mechanical properties;Ti2Cu;Tensile strength;Grain boundaries
摘要：
The beta-type Ti35NbxCu alloys (x = 0, 1, 3, 5, and 7 wt%) were produced by laser powder bed fusion (LPBF) and the influence of Cu content on the microstructure and mechanical properties was studied. The results indicate that when the content of Cu is less than 3 wt%, Cu can diffuse completely into the Ti matrix to form solid solution without element segregation. Moreover, the elastic modulus of Ti35Nb1Cu alloy (49.1 +/- 1.6 GPa) is reduced by 33 % compared to that of Ti35Nb alloy (73.2 +/- 1.4 GPa). When the content of Cu exceeds 3 wt%, the eutectoid reaction is activated during the cyclic heating and rapid cooling of LPBF, and the partially supersaturated beta phase is transformed into nano-scale alpha and Ti2Cu phases (beta ->alpha+Ti2Cu). Nano-scale Ti2Cu particles precipitated along beta grain boundary results in a pinning effect, which inhibits the growth of beta grain, hinders dislocation movement, and improves the strength of the alloy. However, when the content of Cu is 7 wt%, the dislocation density (4.179 x 1015 m 2) and the ratio of brittle phase Ti2Cu (8.5 %) are too high, and the stress concentration caused by the initiation of inherent micro-cracks are the main reason for the tensile brittle fracture of Ti35Nb7Cu alloy. As such, the Ti35Nb5Cu alloy has the highest tensile strength of 867.3 +/- 24 MPa and the elongation reaches 11.7 +/- 0.5 %. Therefore, solution strengthening of Cu, fine grain strengthening of beta, dislocation strengthening, and precipitation strengthening of Ti2Cu are the main reasons for the excellent comprehensive mechanical properties of Ti35Nb5Cu alloy.
作者机构：
[Wang, Huajun; Wang, HJ; Shao, Yuanhai] Changsha Univ Sci & Technol, Dept Math & Stat, Changsha, Peoples R China.
通讯机构：
[Wang, HJ ] C;Changsha Univ Sci & Technol, Dept Math & Stat, Changsha, Peoples R China.
关键词：
Generalized ramp loss;LR-SVM;LR proximal operator;Working set;LR support vectors;LR-ADMM
摘要：
Support vector machine (SVM) is widely recognized as an effective classification tool and has demonstrated superior performance in diverse applications. However, for large-scale pattern classification problems, it may require much memory and incur prohibitive computational costs. Motivated by this, we propose a new SVM model with novel generalized ramp loss (LR-SVM). The first-order optimality conditions for the non-convex and non-smooth LR-SVM are developed by the newly developed P-stationary point, based on which, the LR support vectors and working set of LR-SVM are defined, interestingly, which shows that all of the LR support vectors are on the two support hyperplanes under mild conditions. A fast proximal alternating direction method of multipliers with working set (LR-ADMM) is developed to handle LR-SVM and LR-ADMM has been demonstrated to achieve global convergence while maintaining a significantly low computational complexity. Numerical comparisons with nine leading solvers show that LR-ADMM demonstrates outstanding performance, particularly when applied to large-scale pattern classification problems with fewer support vectors, higher prediction accuracy and shorter computational time.
摘要：
Microplastics (MPs) have attracted much attention in recent years, due to the difficulty of degradation and threats to ecological systems and humans. Based on the analysis of 1429 articles on MPs in soil, we found that we know little about the behavior and fate of manure-born MPs from the livestock and poultry production systems to agriculture soils. This review summarizes the analytical methods for sampling, separation, and identification and the occurrence of MPs in livestock and poultry manure, mainly based on 7 surveys related to manure-born MPs. Then, the sources, fate, and environmental risks of MPs in livestock and poultry manure are discussed. MPs, heavy metals, pathogens, antibiotic resistance genes, and persistent organic pollutants are common pollutants in livestock and poultry manure. Worse, manure-born MPs will become smaller, rougher, and more numerous and could easily form more toxic compound pollution after complicated processes of manure treatment, which seriously threatens agricultural soil safety. Finally, an outlook is offered for future research. We hope this article to attract attention to the risks of MPs in livestock and poultry manure and provide a reference for future research.
通讯机构：
[Hu, YF ] H;[Qing, ZH ] C;[Hu, YF; Guo, ZY ] N;Ningbo Univ, Sch Mat Sci & Chem Engn, State Key Lab Base Novel Funct Mat & Preparat Sci, Ningbo 315211, Zhejiang, Peoples R China.;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.
摘要：
The detection of lysine acetyltransferases is crucial for diagnosing and treating lung cancer, highlighting the necessity for highly efficient detection methods. We developed a portable, highly accurate, and sensitive technique using fast-scan cyclic voltammetry (FSCV) to determine the activity of the lysine acetyltransferase TIP60, employing a novel miniature electrochemical sensor. This approach involves a compact electrochemical cell, merely 3 mm in diameter, that holds solutions up to 50 μL, equipped with a conductive indium tin oxide working electrode. Uniquely, this system operates on a two-electrode model compatible with the FSCV, obviating the traditional requirement for a reference electrode. The system detects TIP60 activity through the continuous generation of CoA molecules that engage in reactions with Cu(II), thereby significantly improving the accuracy of the acetylation analysis. Remarkably, the detection limit achieved for TIP60 is notably low at 3.3 pg/mL (S/N = 3). The results show that the reversible dynamic acetylation can be effectively regulated by inhibitor incubation and glucose stimulation. This cutting-edge strategy enhances the analysis of a broad spectrum of biomarkers by modifying the responsive unit, and its miniaturization and portability significantly amplify its applicability in biomedical research, promising it to be a versatile tool for early diagnostic and therapeutic interventions in lung cancer.
摘要：
The aging precipitation behavior of super austenitic stainless steels 904L (4.32% Mo), 254SMo (6.06% Mo), and AL-6XN (6.29% Mo) with different Mo contents at 800degree celsius-900degree celsius was investigated by scanning electron microscopy, X-ray diffraction, and transmission electron microscopy, and the effect of Mo content on the sigma-phase precipitation behavior of commonly used super austenitic stainless steels was explored. The effect of Mo content on the sigma-phase precipitation behavior of commonly used super austenitic stainless steel was investigated. The results show that the super austenitic stainless steels with different Mo contents formed different numbers and shapes of sigma-phases in the isothermal aging process, and the number of sigma-phases of 254SMo and AL-6XN is much larger than that of 904L, and the shape of the sigma-phases mainly shows coarse acicularity and elongation, while the sigma-phases of 904L show fine granularity.
关键词：
Distribution network;Unmanned aerial vehicle (UAV);Image segmentation;Improved weIghted meaN oF vectOrs (IINFO)
摘要：
Distribution grid network has problems such as long mileage, large scale, complex surrounding environment, and aging of equipment. It is the development trend of power distribution network operation and maintenance to use unmanned aerial vehicles to patrol and combine with image processing technology for intelligent detection of equipment status. Image segmentation is well-known technique for extracting defect regions of equipment from distribution network inspection images. Therefore, this paper proposes an efficient a novel multilevel thresholding segmentation method to improve the fault diagnosis process with an improved weighted mean of vectors optimization (IINFO) algorithm. The IINFO algorithm adopts various measures to improve the optimization results, including Gaussian mutation to increase the local search ability and range of the optimal individual, Cauchy mutation to enhance the global search ability of its vector individual, reflective learning operators to strengthen self-learning and avoid local optimal solutions, and parallel operation to improve the utilization of computational resources. Moreover, two-dimensional Kapur cross-entropy is used as an objective function to solve the multilevel thresholding problem. The proposed method is evaluated using benchmark functions and distribution network inspection image datasets and is compared with 12 other metaheuristic algorithms. The results demonstrate that the proposed method has better performance and a higher ability to find optimal solutions compared to the other algorithms. These findings suggest that our method may be useful in improving the accuracy and efficiency of distribution network inspections and have significant potential for practical applications.
摘要：
Phytoremediation is a cost-effective and eco-friendly plant-based approach promising technique to repair heavy metal-contaminated soils. However, a significant quantity of plant residues needs to be properly treated and utilized. Pyrolysis is an effective technology for converting residues to biochar, which can solve the problem and avoid secondary contamination. This paper reviews the generation, and physicochemical properties of biochar from phytoremediation residues, and its application in soil improvement, environmental remediation, and carbon sequestration. In spite of this, it is important to be aware of the potential toxicity of heavy metals in biochar and the environmental risks of biochar before applying it to practical applications. Future challenges in the production and application of residue-derived biochar include the rational selection of pyrolysis parameters and proper handling of potentially hazardous components in the biochar.
关键词：
Structural optimization;Confined polyhedral pipeline;Stability;Pressure and thermal fields;Configuration factor
摘要：
This paper investigates the structural optimization of a polyhedral composite subsea pipeline (cylinder) under pressure and thermal fields. The pipeline is confined tightly and deforms inward when it is subjected to external loadings. The interface is frictionless between the pipeline and its surrounding medium. Based on the above assumptions, thin-walled shell principles, and an admissible displacement function, the potential energy of a pipeline per unit length is obtained explicitly by simplifying the radius and bending rigidity. After taking the first derivative of the potential energy, two equilibrium equations are obtained. By combining these two equations, the critical buckling pressure of the polyhedral pipeline is expressed analytically with the inclusion of the temperature effects. Then, the present analytical study is compared with other numerical and experimental results, and excellent agreements are reached. A configuration factor is defined as the buckling pressure between the polyhedral and circular pipeline. Finally, parametric studies show the configuration factor decreases with the increase of thickness-to-radius ratio, the increase of the number of sides, and the increase of the temperature variation, respectively. Therefore, a polyhedral pipeline with a low thickness-to-radius ratio is recommended in engineering practices since it may reduce the material cost.
期刊：
Scandinavian Journal of Statistics,2024年 ISSN：0303-6898
通讯作者：
Zhu, EW
作者机构：
[Cai, Bibi; Ling, Shiqing] Hong Kong Univ Sci & Technol, Dept Math, Hong Kong, Peoples R China.;[Zhu, Enwen] Changsha Univ Sci & Technol, Sch Math & Stat, Changsha, Peoples R China.
通讯机构：
[Zhu, EW ] C;Changsha Univ Sci & Technol, Sch Math & Stat, Changsha, Peoples R China.
关键词：
ARMA model;AR-TFV model;LSE;model checking
摘要：
Abstract This paper studies the autoregressive and moving average (ARMA) model with time‐functional variance (TFV) noises, called the ARMA‐TFV model. We first establish the consistency and asymptotic normality of its least squares estimator (LSE). The Wald tests and portmanteau tests are constructed based on the theory for variable selection and model checking. A simulation study is carried out to assess the performance of our approach in finite samples, and two real examples are given. It should be mentioned that the process generated from the ARMA‐TFV model is not stationary, and the technique in this paper is nonstandard and may provide insights for future research in this area.
