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In this paper, we investigate the well-posedness of stochastic variational inequalities on ℝd with discontinuous drift coefficients. First, a case that drift coefficients are only integrable on (0,T) × ℝd is considered. Utilizing Girsanov’s theorem, Zvonkin’s transform and Yamada–Watanabe’s principle, we derive the weak well-posedness if d > 1 and strong well-posedness if d = 1. Second, if the drift coefficients are piecewise Lipschitz continuous and d = 1, strong well-posedness is also obtained by virtue of a transform which regularizes the discontinuous drifts. [ABSTRACT FROM AUTHOR]

Predicting the crystal structure is essential to address the reliance on serendipity for facilitating the discovery and design of high‐performance high‐entropy oxides (HEOs). Here, three classic algorithms‐based machine learning models to predict the crystal structure of HEOs are successfully established and analyzed by combining five metrics, and the XGBoost classifier shows excellent accuracy and robustness with ACC and F1 scores up to 0.977 and 0.975, respectively. SHAP summary plot indicates that the anion‐to‐cation radius ratio (rA/rC) has the greatest impact on crystal structure, followed by difference in Pauling and Mulliken electronegativities (ΔχPauling and ΔχMulliken). It is noteworthy that the rA/rC, ΔχPauling, and ΔχMulliken lower than 0.35, 0.1, and 0.2, respectively, tend to lead to a fluorite crystal structure, whereas rock‐salt and spinel crystal structures are always formed. This work is expected to facilitate the discovery and design of HEOs with tailorable crystal structures and properties. [ABSTRACT FROM AUTHOR]

Although inorganic salts are considered outstanding thermal storage materials, drawbacks such as low thermal conductivity, corrosion issues, and leakage severely hinder their practical industrial application. Porous ceramics are suitable to serve as the supporting skeleton for inorganic salt due to good corrosion resistance, high thermal conductivity and high porosity. In this study, secondary aluminum dross (SAD) and ferronickel slag (FNS) were used as raw materials to prepare cordierite-mullite porous ceramic (CMC). The NaNO 3 /CMC composites were synthesized using spontaneous melting-infiltrating method, and their thermal storage performance were studied in detail. The results indicated that CMC had a favorable pore structure with high porosity and micro-sized pores, as well as high compressive strength exceeding 30 MPa. Excellent chemical compatibility between CMC and NaNO 3 was demonstrated by XRD analysis. The latent heat of the NaNO 3 /CMC5, NaNO 3 /CMC15 and NaNO 3 /CMC30 composites, as determined by DSC, were 76.4 J/g, 76.7 J/g and 73.6 J/g, respectively, accounting for 43.5%,43.6% and 41.9% of pure NaNO 3. The supercooling of NaNO 3 was significantly decreased after infiltration into CMC supporting skeleton. A 100-cycle thermal cycles experiment was conducted to verify the long-term thermal reliability of the NaNO 3 /CMC composites, including latent heat and heat transfer property. The melting latent heat of the NaNO 3 /CMC5, NaNO 3 /CMC15 and NaNO 3 /CMC30 decreased by nearly 5.6%, 3.7% and 2.9%, respectively, after 100 thermal cycling tests, indicating the NaNO 3 /CMC composites had good thermal reliability. The thermal conductivity of all the NaNO 3 /CMC composites exceeded 1.8 W m−1 K−1 at 350 °C. Additionally, the compressive strength of all the composites showed only minimal decrease after thermal cycling test, remaining higher than 100 MPa. The NaNO 3 /CMC composites offer promising prospects in the medium temperature thermal storage utilization field, such as industrial waste heat recovery, owing to low production cost, high thermal conductivity and high mechanical strength. • Excellent chemical compatibility between CMC and NaNO 3 was verified. • The latent heat of NaNO 3 /CMC composite was more than 40% of that of pure NaNO 3. • Good thermal reliability of NaNO 3 /CMC composite was demonstrated. • The thermal conductivity of NaNO 3 /CMC composite exceeds 1.8 W/(m·K) even after 100 thermal cycles. [ABSTRACT FROM AUTHOR]

Wind energy is an important renewable clean energy resource. However, the stochastic and volatile nature of wind power brings significant challenges to the power system's reliable and secure operation. Accurate and reliable wind power prediction is critical for the integration of wind power into the grid. The existing wind power forecasting (WPF) methods lack an assessment of the reliability of the predicted results, which may result in a financial penalty for the wind energy producers. An accurate prediction with reliability measurement is urgently needed to encounter the intricate nature of the problem. In this paper, a Bayesian framework-based bidirectional gated logic unit (BiGRU) method was proposed for ultra-short-term wind power forecasting. First, an encoder-decoder (ED) architecture was combined with a BiGRU time series modeling and feature–temporal attention (FT-Attention) to improve the accuracy of wind power prediction. Then, two uncertainty losses were applied to improve the model's performance further. The proposed method obtains the uncertainty of forecast results, which effectively eliminates the untrusted results. Our proposed method demonstrated promising results for ultra-short-term wind power forecasting due to its competitive performance compared with traditional forecasting methods. • A novel ultra-short-term WPF method is proposed with a deep Bayesian model. • Quantifying the uncertainty of WPF is a unique ability of our proposed framework. • Aleatoric uncertainty loss and epistemic uncertainty loss are introduced. • Temporal attention and feature attention are designed to enhance the accuracy of WPF. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper is devoted to the synchronization of stochastic lattice dynamical systems driven by fractional Brownian motion with Hurst parameter 1 2 < H < 1 . We first prove that the synchronization of any two solutions occurs and then we also show that the synchronization of any two components of solutions of the coupled stochastic lattice dynamical systems occurs. Moreover, the convergence rate of synchronization is obtained. [ABSTRACT FROM AUTHOR]

Because of the low utilization rate, a large amount of metallurgical slag was piled up or buried each year, resulting in serious environmental pollution and resource waste. This study focused on the value‐add utilization of secondary aluminum dross (SAD) and ferronickel slag (FNS) by preparing porous cordierite–mullite ceramics (CMC) for thermal insulation. The detailed thermodynamic calculation of the preparing process was carried out by using the phase diagram and equilibrium component function module in FactSage 8.1 software, which provided precise theoretical guidance for the practical synthesis experiment. The phase component, microstructure, and mechanical and thermal insulation properties of the prepared CMC at an FNS addition from 5 to 30 wt% were investigated by an X‐ray diffractometer, scanning electron microscopy assembled with an energy‐dispersive spectrometer, and a laser thermal conductivity testing instrument, respectively. It was shown that the original mineral phase of the raw materials applied can be converted to cordierite, mullite, and spinel after sintering at 1350°C, which results in higher strength and lower thermal conductivity of the prepared ceramics. Moreover, the increase of FNS addition promoted the content of cordierite and the microstructure densification of CMC. With the increase of FNS addition, the apparent porosity of CMC decreased from 41.7% to 34.4%, and the average pore size varied from 46.7 to 29.0 μm. The CMC with the lowest thermal conductivity of 0.86 W/(m K) was achieved at 20 wt% of FNS addition, which also had a good compressive strength of 52.8 MPa. The results proved the feasibility of preparing high‐strength thermal insulation ceramics by recycling hazardous metallurgical slag of SAD and FNS, proposing a novel route for high value‐added utilization of industrial solid waste. [ABSTRACT FROM AUTHOR]

We develop the large deviations principle for synchronized system with small noise. Depending on the interaction between the intensity of the noise with coupling strength, we get different behavior. By simple transformations, the original synchronized system is equivalently converted into the slow-fast system, then we derive the representations for the action functional of the slow variables via weak convergence methods. Therefore, the large deviation properties corresponding to the original synchronized system are derived. In particular, we present a large deviation principle for a particular system in view of Smoluchowski–Kramers arguments and study the synchronization of the quasipotential for a linear system. [ABSTRACT FROM AUTHOR]

In this paper, we shall prove a stochastic averaging principle for two-time-scale jump-diffusion SDEs under the non-Lipschitz coefficients. [ABSTRACT FROM AUTHOR]

Clean energy has become one of the more broadly acceptable options for the future transformation of existing energy systems. The energy transformation also requires comprehensive preparatory actions. Organizing a multi-chain clean energy value chain into a complex clean energy network system is likely to be critical to the successful utilization of clean energy in the future. This article proposes a novel concept for a clean energy value co-creation system covering the entire clean energy value chain with division on power generation, energy storage, and end utilization sections. This article mainly analyzes the self-organizing evolution mechanism and value co-creation of the clean energy value co-creation system (CEVCS), which is therefore critical to the further development of the renewable energy industry. First, this article analyzes the connotation and basic structure of CEVCS and introduces the self-organizing characteristics of CEVCS. Second, the self-organizing evolution mechanism of CEVCS is discussed, which is analyzed from four aspects: evolutionary power, evolutionary path, evolutionary form, and evolutionary process. Third, this paper analyzes the information cooperative evolution process of CEVCS, defines the value order parameter, and studies how the constituent elements of CEVCS realize value creation through a synergy mechanism based on the theory of synergy. Then the dissipative structure model and information resource collaborative model of CEVCS are presented. Finally, the conclusions are given in the end. The proposed CEVCS concept would support the effective operation of the clean energy value chain within municipalities by establishing virtual energy cooperatives aimed at meeting energy needs and supporting community development. [ABSTRACT FROM AUTHOR]

After the rapid development of China's wind power industry, the lack of core technology and the mismatch between the expansion and development speed have become increasingly prominent. In order to correctly understand the current situation and problems, the whole research process is divided into the following four steps. The first step takes the profit rate of main business from 2017 to 2019 as sample variable to study the smile pattern of the wind power industry value chain. The second step takes the Principal Component Analysis as the research method, and the evaluation index system is constructed, so as to further analyze the value-added driving factors. The third step uses the Data Envelopment Analysis (DEA) and Malmquist model as evaluation methods, and the static and dynamic efficiencies of each value chain link are evaluated, respectively. In step four, the selected companies are effectively clustered with the Cluster Analysis. The results show that the value chain shows a gradual deepening smile, the overall value-added efficiency is not ideal, and there are specific problems in each link. This paper aims to provide reference for enterprises to make targeted improvement on the basis of analyzing the current situation. It also provides reference for the comparison and promotion of other countries. [ABSTRACT FROM AUTHOR]

Photovoltaic storage system (PVSS) has been spawned with the combined application of photovoltaic (PV), energy storage (ES) and energy blockchain (EB), which has also made important contributions to the energy structure adjustment, energy transaction security and ecological environment protection. The establishment of a reasonable task matching mechanism can further improve the operation efficiency and quality of the system under the EB environment, and this paper consequently constructs a task matching model of PVSS based on GA-CLOUD-GS algorithm. Firstly, the decision-making committee is set up and the index system is determined for the to-be-matched task. Secondly, the Genetic Algorithm (GA) comprehensive weighting method is introduced to integrate the subjective and objective weights to achieve the weight optimization. Thirdly, the cloud model is used to obtain the preference order and priority order of the to-be-matched subjects. Fourthly, the Gale-Shapley (GS) algorithm is used to obtain the task matching results. Finally, the operability, the stability and the effectiveness of the model are separately verified through numerical simulation, sensitivity analysis and comparative analysis. Corresponding suggestions for the task matching of PVSS in the EB environment are also put forward according to the research content. • The necessity, superiority, and application scenarios of collaborative development between PVSS and EB are clarified, and the importance of research on task matching mechanism is identified. • A task matching mechanism model based on the GA-CLOUD-GS algorithm is established, the feasibility, stability, and effectiveness of the established model were verified. • Relevant suggestions are provided for the development of PVSS in the EB environment. [ABSTRACT FROM AUTHOR]

Much research has been carried out on the bacterial bioremediation of soil contaminated with petroleum hydrocarbons and toxic metals but much less is known about the potential of fungi in sites that are co-contaminated with both classes of pollutants. This article documents the roles of fungi in soil polluted with both petroleum hydrocarbons and toxic metals as well as the mechanisms involved in the biotransformation of such substances. Soil characteristics (e.g., structural components, pH, and temperature) and intracellular or excreted extracellular enzymes and metabolites are crucial factors which affect the efficiency of combined pollutant transformations. At present, bioremediation of soil co-contaminated with petroleum hydrocarbons and toxic metals is mostly focused on the removal, detoxification, or degradation efficiency of single or composite pollutants of each type. Little research has been carried out on the metabolism of fungi in response to complex pollutant stress. To overcome current bottlenecks in understanding fungal bioremediation, the potential of new approaches, e.g., gradient diffusion film technology (DGT) and metabolomics, is also discussed. Key points: • Fungi play important roles in soil co-contaminated with TPH and toxic metals. • Soil characteristics, enzymes, and metabolites are major factors in bioremediation. • DGT and metabolomics can be applied to overcome current bottlenecks. [ABSTRACT FROM AUTHOR]

With the rapid development of the wind power value chain, the selection of appropriate node companies has become the focus of wind power alliance, especially in the value chain of energy storage. Through the optimization of the selection of energy storage node enterprises, the role of energy storage in the wind power value chain can be better utilized. At the same time, the optimal selection of energy storage nodes can accelerate the realization of value increment in the wind power value chain. In this study, we combine Interval type-2 fuzzy number and Grey Theory the Interval type-2 fuzzy number with Cumulative Prospect Theory, which is called IGCPT, and select the optimal energy storage nodes in the value chain based on it. First, considering the sustainable development of the entire value chain, 10 decision criteria from the four dimensions of BOCR: benefits, opportunities, costs, and risks are determined. Based on this, the IGCPT method is used to select the optimal scheme, and an optimization model is proposed to determine the significance of the criteria. Then, through the comparative analysis of the multi-criteria decision-making method and the sensitivity analysis of the obtained results, it is shown that the method can be effectively applied to the selection of energy storage nodes in the wind power value chain. Finally, suggestions and conclusions for the selection of wind power value chain node companies are given. [ABSTRACT FROM AUTHOR]

Over the past years, wind energy has been considered as a promising solution for clean and sustainable energy development, but wind curtailment remains a challenge to wind power development. On this basis, utilization of non‐grid‐connected wind power becomes crucial and necessary as it can mitigate wind curtailment and improve energy efficiency. This paper proposes the collaboration strategy and optimization model of wind farm‐hybrid energy storage system (WF‐HESS) for non‐grid‐connected wind power based on battery and superconducting magnetic energy storage (SMES) whose combination can effectively cope with fluctuation and intermittence of wind input. The optimization problem is simultaneously investigated by the minimization of total cost, wind curtailment magnitude, and loss of power supply probability (LPSP). The multi‐objective particle swarm optimization (MOPSO) is introduced to find available solutions, and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) is applied to determine the optimal one. Results are obtained for a case study, and the effectiveness and the feasibility of proposed model are verified by a comparative analysis and a sensitivity analysis. Results analysis and discussion show that the WF‐HESS model and the application of HESS have important influence on promoting utilization of non‐grid‐connected wind power and mitigating wind curtailment. [ABSTRACT FROM AUTHOR]

Energy is the foundation and driving force of modernization. Renewable energy has been developed with the help of global environmental awareness. In recent years, supported by the relevant national industrial policies, China's photovoltaic market has developed rapidly and its production capacity is huge. However, the core of supporting the sustainable development of an industry lies in the continuous appreciation of the value of itself. In order to correctly understand the status quo and problems of PV industry value chain in China, based on the "Smile Curve" theory, taking the gross profit rate of PV industry listed companies as sample variables from 2015 to 2017, the research finds that its value chain shows a gradually deepening smile. And to explore the extent to which gross profit margin is affected by various factors, 15 variables are selected from six aspects: internal innovation power, growth potential, profitability, operational efficiency, scale strength and external environment, the Stepwise Regression method is used to determine the optimal model first. Further use Principal Component Analysis to confirm the motivations affecting the value-added of listed companies in the PV industry in the upper, middle and down reaches. The results indicate that only 6 variables have significant effects on the gross profit margin of the PV industry value chain, and there are big diversities in the main influencing factors of the value-added capacity of PV companies in different links, so they should seek their own value-added breakthroughs. • China's PV industry value chain conforms to the "smile curve" form. • The profitability can significantly influence the value of the entire industry. • Innovation is the key factor to the upper and downstream PV companies' value added. • The key factor to midstream PV companies' value added is operational efficiency. • Company's scale and external environment have synergistic effects on the value added. [ABSTRACT FROM AUTHOR]

Secondary aluminum dross (SAD) is a kind of hazardous waste with high aluminum content produced in the aluminum industry. From another point, SAD is also considered as a valuable aluminum resource, which can be used as high-quality raw material for value-added products such as refractory materials. In this study, a novel route for preparing corundum-spinel heat storage spheres (HSS) using washed residue of secondary aluminum dross (WSAD) as the main raw material was proposed. FactSage 8.1 software was used for the detailed thermodynamic calculation, which provided accurate theoretical guidance for the actual synthesis experiments. The effects of roasting temperature and formula on the main phases, compressive strength, porosity, and bulk density of HSS were systematically analyzed. The strengthening mechanism of the liquid phase on the sintering strength was revealed. The results showed that the HSS with good properties could be obtained with 90 wt% WSAD, 10 wt% kaolin, and 1 wt% bentonite. The HSS mainly consisted of corundum and spinel phases. The synthetic temperature of corundum-spinel ceramic was reduced by more than 200 °C. This study provides a novel way for value-added utilization of SAD as well as realizing the deep detoxification and the removal of nitrogen of it. [ABSTRACT FROM AUTHOR]

Secondary aluminum dross (SAD) is a kind of hazardous waste with high aluminum content produced in the aluminum industry. From another point, SAD is also considered as a valuable aluminum resource, which can be used as high-quality raw material for value-added products such as refractory materials. In this study, a novel route for preparing corundum-spinel heat storage spheres (HSS) using washed residue of secondary aluminum dross (WSAD) as the main raw material was proposed. FactSage 8.1 software was used for the detailed thermodynamic calculation, which provided accurate theoretical guidance for the actual synthesis experiments. The effects of roasting temperature and formula on the main phases, compressive strength, porosity, and bulk density of HSS were systematically analyzed. The strengthening mechanism of the liquid phase on the sintering strength was revealed. The results showed that the HSS with good properties could be obtained with 90 wt% WSAD, 10 wt% kaolin, and 1 wt% bentonite. The HSS mainly consisted of corundum and spinel phases. The synthetic temperature of corundum-spinel ceramic was reduced by more than 200 °C. This study provides a novel way for value-added utilization of SAD as well as realizing the deep detoxification and the removal of nitrogen of it. [ABSTRACT FROM AUTHOR]

Abstract This paper deals with averaging principle for two-time-scale stochastic differential equations (SDEs) with non-Lipschitz coefficients, which extends the existing results: from Lipschitz to non-Lipschitz case. Under suitable conditions, the existence of an averaging equation eliminating the fast variable for coupled system is established, and as a result, the system can be reduced to a single SDEs with a modified coefficient which is also non-Lipschitz. Moreover, it is shown that the slow variable strongly converges to the solution of the corresponding averaging equation. [ABSTRACT FROM AUTHOR]

The synchronization of stochastic differential equations with both additive noise and linear multiplicative noise is investigated in pathwise sense, which generalize the results of [5] and [6]. In our situation, we can deal with the synchronization of the systems with mixed type noise, where one system has the additive noise, another has the linear multiplicative noise. [ABSTRACT FROM AUTHOR]

Abstract In recent years, the wind curtailment has become a serious problem in China and the government are actively seeking solutions to deal with this energy loss. Therefore, the use of non-grid-connected wind power has received great attention since it can be supplied to local end users equipped with energy storage and then mitigate wind curtailment. Since the non-grid-connected wind power and local power load have to confront dramatic power fluctuations, a hybrid energy storage system (HESS) including batteries and supercapacitors is applied. This paper proposes a multi-objective optimization model of HESS configuration in non-grid-connected wind power/energy storage/local user system. In this model, two decision variables, numbers of batteries and supercapacitors, are determined based on the objective of annual profit maximization and wind curtailment rate minimization. To solve this model, a non-dominated sorting genetic algorithm II (NSGA-II) is employed to obtain Pareto front and VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje) technique is applied to select the optimal solution from Pareto solutions. Finally, a wind farm in Hebei province is studied and discussed. A scenario analysis, a sensitivity analysis and a comparative analysis are performed to show the advantages of the proposed model. Highlights • The local consumption of non-grid-connected wind is a solution to wind curtailment. • Hybrid energy storage increases the profit and reduces the wind curtailment rate. • NSGA-II-VIKOR is effective to determine the optimal energy storage capacity. • Energy storage cost and objective weight both influence the optimization result. [ABSTRACT FROM AUTHOR]

Developing new energy is an important way to optimize energy structure, which makes significant sense on improving energy efficiency, reducing carbon emission, and lowering external dependence degree. New energy power generation costs are generally higher than conventional ones at this time. They would quickly decrease because of their scale effects, as technology improving and the scale expanding. Referring to the developing trend of new energy power generation costs, this paper sets the minimize generation costs and pollutant emission as optimization objectives, selects primary energy consumption and new installed generation capacity of each year as decision variables, and establishes an optimization model for new energy and energy structure. By setting and calculating the optimal energy structure, new energy developing scale, generation capacity and building sequences, we can get comparative results of power generation costs under three different scenarios, namely reference scenario, energy security scenario and low-carbon scenario. And use a sensitive analysis to clear the effect of total energy consumption and non-fossil energy consumption proportion. A simulation result shows resource and environmental benefits would be greater than new energy exploration and utilization costs. The larger scale, greater benefits and the less operation cost of the energy system as well as the lower external dependence degree will occur. Therefore, China should adhere to low-carbon energy structure developing direction, to improve energy conversion and utilization efficiency, to strengthen investment in new energy and finally achieve energy development strategies and goals. [ABSTRACT FROM AUTHOR]

The removal of 4 typical pharmaceutically active compounds (PhACs) in sewage sludge, i.e. diclofenac (DCF), clofibric acid (CFA), carbamazepine (CBM), and triclosan (TCS), was evaluated during 3 integrated processes of anaerobic digestions (ADs). The integrated processes included ADs integrated with mixed enzymolyses (MEADs), ADs integrated with mixed enzymolyses together with ultrasonic irradiation pre-treatment (MEUADs), and ADs integrated with mixed enzymolyses together with mechanical rotary disc post-treatment (MEADRDs). The SRTs were set at 15 d. Gas chromatography-mass spectrometry (GC/MS) following solid-phase extraction was used to analyze and detect the target compounds. Under the mesophilic condition, the highest removal during MEAD and MEUAD was 67.6% and 77.1% of CFA, and 78.1% of CBZ during MEADRD. There was little differences between the removals of 4 PhACs during MEADRD, and all the removal rates were higher than 70%. Especially the removal of DCF increased from 40.6% during MEAD to 71.7% during MEADRD. The overall removal during MEADRD was highest with the increase by about 20.9% from that during MEAD. The highest removal during MEAD, MEUAD and MEADRD was 81.1%, 70.7% and 71.8%, respectively, of CFA under the thermophilic condition. MEADRD could realize the highest overall removal, up to 69.4% with the increase by 11.0% compared with MEUAD. The results showed that the integrated process, MEADRD, under both mesophilic and thermophilic condition was suitable for the effective removal of PhACs, and MEADRD under the mesophilic condition was a preferable choice from the energy-saving perspective. [ABSTRACT FROM AUTHOR]

Blast furnace slag (BFS) is a typical solid waste generated in the steel production. Most of previous investigations have reported that the BFS has been used as traditional construction materials (cement, roadbed filling, concrete). In this study, a novel use route for BFS was proposed to prepare high-temperature composite phase change materials (C-PCMs) for thermal energy storage. Three typical inorganic PCMs (NaNO 3 , Al and Na 2 SO 4 with different operating temperature) were blended with the pre-ground BFS to fabricate BFS-based C-PCMs by means of a mixing and sintering process. The results showed that NaNO 3 had excellent chemical compatibility with BFS and the prepared C-PCMs had perfect phase change performance. The enthalpies of NaNO 3 /BFS C-PCMs was 65.53 J/g with melting point 300.5 °C and the super-cooling was only 0.1 °C. Furthermore, the NaNO 3 /BFS C-PCMs could retain good thermal reliability after 100 thermal cycles, which presented a potential application in the thermal energy storage system. In addition, the morphological structure, thermal reliability and heat transfer property of the NaNO 3 /BFS C-PCMs were characterised by using SEM, TGA and TG-DSC. [ABSTRACT FROM AUTHOR]

The existence and uniqueness theorem of solutions provides an effective tool for the model validation of both deterministic and stochastic equations. The objective of this paper is to establish the existence and uniqueness of solutions for a class of Itô-Doob stochastic fractional differential equations under non-Lipschitz condition which is weaker than Lipschitz one and contains it as a special case. The solution is constructed with the aid of Carathéodory approximation. Moreover, the continuous dependence of solutions on the initial value is investigated in view of the stability of solutions in the sense of mean square. Finally, an example is given to illustrate the theory. [ABSTRACT FROM AUTHOR]

The present article focuses on the non parametric estimation of multivariate density and regression functions. We consider the non parametric linear wavelet-based estimators and investigate the strong consistency from the theoretical viewpoint. In particular, we prove the strong uniform consistency properties of these estimators, over compact subsets of R d , with the determination of the corresponding rates of convergence. As a main contribution, we relax some standard dependence conditions by considering the general concept of the causal α ˜ -weak dependence, including mixing concepts and adapted to diverse classes of interesting statistical processes, essentially the general Bernoulli shifts and the Markov sequences. [ABSTRACT FROM AUTHOR]

Here, the limitations of characteristic length‐based (Lchb) and grain size‐based (Gb) criteria with two or three parameters were pointed out employing the apparent toughness tests of 12 different ceramics at a large span range of U‐notch root radius (ρ) values. After comprehensively considering the potential influencing factors of stress intensity factor (Kc), ρ divided by critical notch tip radius (ρc) was proposed as the independent variable, and the data of 21 materials (covering ceramics, plastics, resins, rocks, and metals) was summarized and discussed to establish a simple and more applicable Kc prediction model. Results indicated that Kc/KIc was a power function of ρ/ρc with a power exponent n of 0.5 for ideal materials and less than 0.5 for actual materials. It was also found that ρc can be calculated simply by KIc2/(πσ02), where σ0 represented the inherent strength. This semiempirical criterion succeeded in unifying the Lchb and Gb criteria without introducing more parameters to increase the prediction accuracy of the Kc at the U‐notch root for brittle materials like ceramics. [ABSTRACT FROM AUTHOR]

An M / M / 1 queue with reneging, catastrophes, server failures and repairs is considered. The arrivals follow a Poisson process and the servers serve according to an exponential distribution. On arrival a customer decides to join the queue and after joining the queue if a customer has to wait for the service longer than his expectation, he may renege. Explicit expression for the time-dependent probabilities of the system size is obtained in terms of the modified Bessel function of first kind by making use of Laplace transform and probability generating function techniques. The system queue length and failure distribution for steady state are derived. Additionally, time-dependent mean and variance are obtained. A numerical example is presented to study the behavior of the system. [ABSTRACT FROM AUTHOR]

In the current study, molten NaNO 3 shape-stabilized phase change materials (SS-PCMs) based on anorthite ceramic and cordierite ceramic were prepared by cold-press sintering method. Chemical compatibility and wettability were considered simultaneously to determine whether the ceramics were qualified as supporting skeleton and the enhancement of the thermal properties of NaNO 3 by the ceramics was also investigated. It was found that both anorthite ceramic and cordierite ceramic have good chemical compatibility with NaNO 3 and no chemical reaction occurred between them. Physical compatibility was evaluated by measuring the contact angle of molten NaNO 3 on a ceramic substrate. Cordierite ceramic exhibited better wettability than anorthite ceramic, although both of the contact angles decreased gradually with increasing temperature. The supercooling of the prepared anorthite ceramic-based SS-PCMs with 45 wt% NaNO 3 (45ASS-PCMs) was only 0.7 °C, which was less than 2.5 °C for pure NaNO 3 and 2.0 °C for cordierite ceramic-based SS-PCMs with 45 wt% NaNO 3 (45CSS-PCMs). The phase transition enthalpy loss of 45ASS-PCMs after 100 thermal cycles was less than 2%, while 45CSS-PCMs reached more than 5%. Anorthite ceramic showed better capabilities than cordierite ceramic in terms of thermal reliability and stability, while cordierite ceramic was better than anorthite ceramic in enhancing thermal conductivity. The evaluation method proposed in this study provided favorable guidance for the matching of PCMs and ceramic supporting skeleton. • Evaluating supporting skeleton for PCMs based on chemical and physical compatibility was proposed. • Wettability of NaNO 3 on cordierite ceramic was better than that of anorthite ceramic. • Cordierite ceramic has better shape-stabilized performance but poorer thermal cycle stability than anorthite ceramic. • Thermal conductivity of 45ASS-PCMs and 45CSS-PCMs was enhanced by 2 and 3 times compared with NaNO 3 , respectively. [ABSTRACT FROM AUTHOR]

Electric vehicle sharing (EVS) has been recognized as a promising solution to growing issues of traffic congestion, air pollution and insufficient parking spaces. This study assesses service performance of EVS programs in order to help operators improve service quality and attract more customers. First, this paper identifies 22 criteria from the perspectives of electric vehicles, charging stations, payment and Internet services and establishes the evaluation index system. Then a VIsekriterijumska Optimizacija I Kompromisno Resenje (VIKOR) based approach is proposed with three main steps including processing the criteria values represented by crisp values, interval numbers and linguistic variables, determining integrated criteria weights and assessing alternatives by VIKOR method. Next, a case study is provided to verify the feasibility and effectiveness of the proposed method. Three candidate EVS programs in Beijing are evaluated and ranked according to their scores. A sensitivity analysis and a comparative analysis of different methods are also performed to show that the proposed method is capable to assess service performance of EVS programs. Finally, suggestions are made for program operators according to assessment result. [ABSTRACT FROM AUTHOR]

Installing a photovoltaic (PV) power plant at a proper location has been a critical problem for the system planners and investors. In this study, grey cumulative prospect theory is employed to study the site selection of PV power plants from the perspective of sustainability. First, considering the sustainable development, eight decision-making criteria are identified and divided into three categories: geographical conditions, economic profits and environmental benefits. The decision-making steps of grey cumulative prospect theory are then proposed to select the optimal alternative and in this method, an optimization model is used to obtain the importance of criteria. The proposed method has also been implemented in a case of four cities in Northwest China in which the optimal alternative, Yulin city, is selected with the highest prospect value. Finally, a comparison analysis of multi-criteria decision-making methods and a sensitivity analysis of all criteria are performed and the results show that the proposed method can be used effectively for the site selection of PV power plants. [ABSTRACT FROM AUTHOR]

"Photovoltaic + energy storage" is considered as one of the effective means to improve the efficiency of clean energy utilization. In the era of energy sharing, the "photovoltaic - energy storage - utilization (PVESU)" model can create a more favorable market environment. However, the various uncertainties in the construction of the PVESU project have become the main obstacles to the development of the PVESU model. This paper aims to evaluate the risk level of China's PVESU projects through an improved Cloud-TODIM (Cloud-an acronym in Portuguese for Interative Multi-criteria Decision Making) method. First of all, 18 critical risk factors are identified using the constructed five-dimensional risk analysis model. Secondly, the improved method is used to calculate the weight of the comprehensive criteria and rank 14 PVESU alternatives. Finally, the accuracy and feasibility of the hybrid method are verified by sensitivity analysis tests concluding the loss decay coefficient adjustment and comparison analysis with the Cloud-TOPSIS(Cloud-Technique for Order of Preference by Similarity to Ideal Solution) method. Meanwhile, in terms of energy storage, some suggestions are made for the future development of China's PVESU project. This study can also provide insightful enlightenment for PVESU project investors, risk management professionals and decision makers. • The highlights stated are as follows: • Construct an evaluation system of Photovoltaic - Energy storage - Utilization (PVESU) project risk assessment. • Contribute to adding five-dimensional risk analysis method to select critical risk factors. • Propose an improved Cloud-TODIM method to analyze the risk level of PVESU projects. • Extend the research on integrated projects on the field of clean energy and energy storage. [ABSTRACT FROM AUTHOR]

The realization of carbon neutral goal is inseparable from the development of new energy industry, and scientific and effective policy support can accelerate the progress of the goal. In this paper, the policy driven ability of China's photovoltaic industry in the background of carbon neutral is evaluated. Firstly, the evaluation system is established by the improved diamond model. Then, the policy evaluation standard is formulated according to the Interval Type-2 Fuzzy sets (IT2FS). Finally, the weight of each index is determined by using the fuzzy OWA operator weighting method (F-OWA). Then, the policy driving ability of China's photovoltaic industry is evaluated by fuzzy matter-element extension method (F-MEEM), and the effectiveness of the evaluation results is further verified by weight sensitivity analysis. According to the evaluation results, policy support plays an important role in the development of photovoltaic industry. This paper also gives policy suggestions for the development of China's photovoltaic industry under the background of carbon neutral from the macro, meso and micro perspectives. • China's PV industry evaluation system is established by the improved diamond model. •IT2FS and F-OWA are used to process indicators. •The policy driving ability of China's PV industry is evaluated by F-MEEM. •The effectiveness of the evaluation results is further verified by weight sensitivity analysis. •The results are analyzed in detail, and corresponding suggestions are put forward. [ABSTRACT FROM AUTHOR]

We investigate the effect of domain perturbation on the behavior of mild solutions for a class of semilinear stochastic partial differential equations subject to the Dirichlet boundary condition. Under some assumptions, we obtain an estimate for the mild solutions under changes of the domain. [ABSTRACT FROM AUTHOR]

We prove a strong convergence rate of the averaging principle for general two-time-scales stochastic evolution equations driven by cylindrical Wiener processes. In particular, our general result can be used to deal with a large class of quasi-linear stochastic partial differential equations, such as stochastic reaction–diffusion equations, stochastic p-Laplace equations, stochastic porous media equations, and so on. [ABSTRACT FROM AUTHOR]

The averaging principle for multivalued stochastic differential equations (MSDEs) driven by Brownian motion with Brownian noise is investigated. An averaged MSDEs for the original MSDEs is proposed, and their solutions are quantitatively compared. Under suitable assumptions, it is shown that the solution of the MSDEs converges to that of the original MSDEs in the sense of mean square and also in probability. Two examples are presented to illustrate the averaging principle. [ABSTRACT FROM PUBLISHER]

In order to implement the national need for the optimal allocation of power resources, power load forecasting, as an important research topic, has important theoretical and practical significance. The purpose of this study is to construct a prediction model considering climate factors based on a large amount of historical data, and to prove that the prediction accuracy is related to both climate factors and load regularity. The results of load forecasting are affected by many climate factors, so firstly the climate variables affecting load forecasting are screened. Secondly, a load prediction model based on the IPSO-Elman network learning algorithm is constructed by taking the difference between the predicted value of the neural network and the actual value as the fitness function of particle swarm optimization. In view of the great influence of weights and thresholds on the prediction accuracy of the Elman neural network, the particle swarm optimization algorithm (PSO) is used to optimize parameters in order to improve the prediction accuracy of ELMAN neural network. Thirdly, prediction with and without climate factors is compared and analyzed, and the prediction accuracy of the model compared by using cosine distance and various error indicators. Finally, the stability discriminant index of historical load regularity is introduced to prove that the accuracy of the prediction model is related to the regularity of historical load in the forecast area. The prediction method proposed in this paper can provide reference for power system scheduling. [ABSTRACT FROM AUTHOR]

Micro-grid operation mode, which is the combination of a power grid and distributed generation, is the main way for saving investment, reducing energy consumption, and improving a power system's reliability and flexibility, but it has many risks in the process of implementation. In this article, the micro-grid generation structure of a wind farm was established, a processing flow chart of an intelligent management system was drawn, and a risk management model of a micro-grid wind farm was built from the angle of cost risk, including construction of cost risk and operation cost risk models. The construction cost risk model, grid-connected operation, and isolate-operation cost risk model of a micro-grid wind farm were set up by using a mathematical model that consisted of an objective function and constraint conditions. The accuracy of the model was verified through empirical analysis. This provides a reference and mirror for solving grid-connected wind energy problems and gives an important basis for wind energy risk policy-making, and for avoiding the risks in the process of planning, design, and operation management of a wind farm. [ABSTRACT FROM AUTHOR]

The existence and uniqueness of the solutions for a class of hyperbolic type stochastic evolution equations driven by some non-Gaussian Lévy processes are obtained. Moreover, an energy equality for the solutions of the equations is established. As examples, theses results are applied to a couple of stochastic wave type equations with jumps. [ABSTRACT FROM AUTHOR]

Abstract: We prove some conditional Borel–Cantelli lemmas for sequences of random variables. As an application, a conditional version of the weighted Borel–Cantelli lemma is obtained. [Copyright &y& Elsevier]

Abstract: A water-soluble polysaccharide, designated as EFP-AW1, was isolated from the roots of Euphorbia fischeriana and purified to homogeneity by gel-filtration chromatography. Its carbohydrate content was up to 92.34%, which was composed of glucose (Glc), galactose (Gal), mannose (Man) and rhamnose (Rha) in a molar ratio of 14.1:1.9:2.0:1.9. The molecular weight was evaluated to be 10,830Da as determined by high performance size exclusion chromatography (HPSEC). On the basis of sugar analysis, methylation analysis, periodate oxidation, Smith degradation, and nuclear magnetic resonance spectroscopy (NMR) studies (1H and 13C), the structure of the repeating unit of the polysaccharide was established as: Display Omitted [Copyright &y& Elsevier]

Abstract: A water-soluble protein-bound polysaccharide (EFP-W1) was fractioned from roots of Euphorbia fischeriana and purified by gel-filtration chromatography. Its primary structural features were characterized by partial acid hydrolysis, Smith degradation-periodate oxidation, methylation analysis, high performance size exclusion chromatography (HPSEC), fourier transform infrared spectroscopy (FTIR), gas chromatography (GC), gas chromatography–mass spectrometry (GC–MS) analysis and nuclear magnetic resonance spectroscopy (NMR). The data obtained indicated that EFP-W1 contains about 91% of carbohydrate content, which was mainly composed of glucose (Glc), galactose (Gal), mannose (Man), arabinose (Ara) in a molar ratio of 6:1:1:1. Its average molecular weight was about 11,230Da. The structure of the repeating unit of the polysaccharide was elucidated as follows: Display Omitted [Copyright &y& Elsevier]

Abstract: One water-soluble glucan (PCP-W1) was purified from the crude polysaccharide of Pleurotus citrinopileatus by chromatography on DEAE Sepharose Fast Flow and Sephadex G-200 column, and PCP-W1 (Mw =45kDa), was predominantly composed of Glc. Partial acid hydrolysis, Smith degradation–periodate oxidation, methylation analysis, Fourier transform infrared spectroscopy (FTIR), gas chromatography–mass spectrometry (GC–MS) analysis and nuclear magnetic resonance spectroscopy (NMR) experiments were conducted to elucidate its structure. The results indicated that PCP-W1 had a glucan backbone consisting of (1→6)-linked-β-d-glucopyranosyl residues, which were branched at O-3 position of the backbone with (1→3)-linked-β-d-glucopyranosyl and non-reducing end 1-β-d-glucopyranosyl residues. The repeating unit of the polysaccharide was established as: Display Omitted [Copyright &y& Elsevier]

Abstract: The theory of stochastic averaging principle provides an effective approach for the qualitative analysis of stochastic systems with different time-scales and is relatively mature for stochastic ordinary differential equations. In this paper, we study the averaging principle for a class of stochastic partial differential equations with two separated time scales driven by scalar noises. Under suitable assumptions it is shown that the slow component strongly converges to the solution of the corresponding averaged equation. [Copyright &y& Elsevier]

Abstract: One water-soluble polysaccharide (ABP-W1) was purified from the fruiting bodies of Agaricus blazei by DEAE Sepharose Fast Flow and Sepharose 6 Fast Flow column chromatography. Its molecular weight was about 3.9×102 kDa as determined by high-performance size-exclusion chromatography (HPSEC). The structural feature of ABP-W1 was investigated by a combination of chemical and instrumental analysis, including partial hydrolysis with acid, periodate oxidation–Smith degradation, acetylation, methylation analysis and nuclear magnetic resonance spectroscopy (NMR 1H, 13C). The results revealed that ABP-W1 had a backbone consisting of (1→6)-linked-α-d-galactopyranosyl and (1→2,6)-linked-α-d-glucopyranosyl, which was branched with one single terminal (1→)-α-d-glucopyranosyl at the O-2 position of (1→2,6)-linked-α-d-glucopyranosyl along the main chain in the ratio of 1:1:1. The observation of the complex-formation between ABP-W1 and Congo Red indicated that ABP-W1 probably existed in a triple-strand helical conformation in water. Based on the data obtained, ABP-W1 was composed of a repeating unit with a structure as below: Display Omitted [Copyright &y& Elsevier]

Abstract: Response surface methodology (RSM) was used to determine the optimum extraction conditions for polysaccharides (EFP) from the roots of Euphorbia fischeriana. A Box–Behnken design (BBD) with four independent variables was investigated, such as extraction temperature (°C), water/solid ratio, extraction number (n), and extraction time (h). The results indicated optimum extraction conditions were extraction temperature of 97°C, water/solid ratio of 9:1, extraction number of 2 and extraction time of 2.4h, respectively. Under these conditions, the experimental value was 24.6±0.62, which was well in close agreement with value predicted by the model. The preliminary chemical analysis of EFP revealed the EFP contained 25.43% polysaccharides, 20.42% uronic acids, 2.54% sulfate radical and 23.41% proteins. And the neutral polysaccharides were mainly composed of glucose, arabinose, rhamnose, galactose, xylose, mannose in the ratio of 21:8:5:3:1:1. [Copyright &y& Elsevier]

Abstract: An alkali-extractable and water-soluble polysaccharide (ABP-AW1) was isolated by 5% sodium hydroxide solution from the fruiting bodies of Agaricus blazei. ABP-AW1 (M w =50kDa), was composed of Gal, Glc, Fuc, Ara and Man with the molar ratio of 29: 20: 6: 2: 2. According to the combination of chemical and instrumental analysis, the results indicated that ABP-AW1 had a backbone consisting of (1→6)-linked-β-d-galactopyranosyl, (1→6)-linked-β-d-glucopyranosyl and (1→3, 6)-linked-β-d-glucopyranosyl, which was terminated with (1→)–linked Fuc, Ara and Man residues at the O-3 position of (1→3, 6)-linked-β-d-glucopyranosyl in the proportion of 29: 10: 10: 6: 2:2. [Copyright &y& Elsevier]

Abstract: Response surface methodology (RSM) was used to optimize the extraction conditions of polysaccharides from the roots of Codonopsis pilosula. A central composite design (CCD) was used for experimental design and analysis of the results to obtain the optimal processing parameters. Four independent variables such as extraction temperature (°C), ratio of water to raw material, extraction time (h), and number of extraction (n) were investigated. The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis and also analyzed by appropriate statistical methods. The 3-D response surface and the contour plots derived from the mathematical models were applied to determine the optimal conditions. The optimum extraction conditions were as follows: extraction temperature 94°C, ratio of water to raw material 9, extraction time 2.5h, and number of extraction 5. Under these conditions, the experimental percentage value was 15.2±0.28, which is well in close agreement with value predicted by the model. [Copyright &y& Elsevier]