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Abstract In recent years, as the energy market continues to change, an emerging business model is gradually emerging as an energy provider (EP). The participation of EP as an independent entity in the distribution network investment model not only helps realize a win–win situation for multiple stakeholders but also promotes the innovation and sustainable development of the energy industry. However, in the energy system, EPs, grids, microenergy grids (MEGs), and shared energy storage service providers usually belong to different stakeholders, and their respective pursuit of profit maximization can easily lead to uncontrolled competition, which greatly reduces market efficiency. To address the varying ownership structures within the energy system, a refined bilevel coordinated optimization operation model is introduced, rooted in the master–slave game theory. In this model, the EP assumes the role of the master, while the MEG operator and the shared energy storage operator (SESO) act as slaves. A peer‐to‐peer energy‐sharing mechanism between MEGs and an energy trading mechanism between MEGs and shared energy storage is used to further increase the local consumption rate of new energy. Simulation results demonstrate that the proposed method not only boosts the revenues of an EP, SESO, and MEG operators but also effectively accounts for the MEG's energy storage needs and SESOs' profitability.

This paper systematically studies the effect of quenching temperature on the microstructure evolution and the relationship between the microstructure and mechanical properties of air-cooled TRIP steel prepared with C–Si–Mn hot-rolled sheet. The results indicate that when the quenching temperature is lower than (200 °C) or close to (250 °C) the Ms temperature, the martensite transformation mainly occurs during quenching or at early stage of air cooling. When the quenching temperature reaches 300 °C, lathy bainite begins to form. As the quenching temperature increases, the morphology of bainite is transformed from lathy to granular. Bainite transformation during air cooling can promote the C enrichment in austenite, thus improving the thermal stability of the austenite. However, martensite transformation also occurs during subsequent air cooling, and the start temperature of martensite transformation first decreases and then increases with the increase of quenching temperature from 300 °C to 450 °C. The yield and tensile strength of TRIP specimens first decrease and then increase, while the retained austenite content, elongation and product of strength and elongation (PSE) first increase and then decrease. When the quenching temperature is 400 °C, the best elongation and PSE are obtained. The best elongation of 400TRIP specimen is mainly attributed to its highest content and suitable mechanical stability of retained austenite, which is favorable for the expansion of the TRIP effect range. The TRIP specimens prepared with hot-rolled sheet all exhibit ultra-high tensile strength (over 1050 MPa), which is related to the ultrafine ferrite grains, martensite transformation during air cooling and TRIP effect of retained austenite.

Using the planar flow casting method to prepare ultra-thin silicon steel ribbons is an eco-friendly and efficient production method. However, the poor wettability between silicon steel and copper result in difficulties in formability by planar flow casting, which limits its application in production of silicon steel ultra-thin ribbons. The process parameters of planar flow casting are the key factors affecting the formability and magnetic properties of non-oriented silicon steel ribbons, in which the wheel speed determines the solidification rate of the silicon steel melt, which has an important influence on the surface quality and magnetic properties of silicon steel ultra-thin ribbons. Therefore, in this paper, the effect of wheel speed on microstructures and magnetic properties of Fe-3.0 wt %Si alloy are systematically investigated. The results indicate that as the wheel speed increases, the grain size and thickness gradually decrease. When the wheel speed is between 10 and 15 m/s, the surface of the ribbons is relatively flat. As the wheel speed increases, the surface quality of ribbons gradually deteriorates. The ribbons were in fragment with the wheel speed of 35 m/s. Compared with the ribbons before annealing, the magnetic induction B50 increased significantly and the iron losses P1.0/400 decreased sharply at 400 Hz after annealing. The magnetic induction of the ribbons after annealing with the wheel speed of 10 m/s reaches to 1.628 T as the wheel speed is 10 m/s with the corresponding iron loss is 16.171 W/kg. The lower lamination factor and micropores of the ribbons may cause the poorer magnetic properties.

Active front-end converters are part of high power installations for regenerative energy systems, feeding the regenerated energy into the utility. Under the island mode operation of the regenerative energy system, the load characteristics are difficult to detect, and the change of the load characteristics will cause the corresponding resonance. V/f control is usually used to ensure the harmonic quality. At high switching frequency, it has a good control effect. However, high switching frequency causes high switching loss. In order to reduce the switching loss, it will produce more harmonic distortion. Furthermore, the commonly used modulation strategies in this case face the problem of low real-time performance. Therefore, in order to avoid the harm caused by circuit resonance under the condition of reducing the switching frequency, this paper proposes a specific harmonic suppression algorithm with high real-time performance, which can be used as an optional control algorithm in the island operation state of power system. At the same time, aiming at the difficulty of adjusting the weight factors, this paper proposes a weight factor automatic tuner, which automatically adjusts the weight factors according to the harmonic component.

The microstructure evolution and precipitation behavior of hot-rolled Ti–Mo–V micro-alloyed high-strength steel processed at different final rolling temperatures (FRT) and coiling temperatures (CT) were investigated. The results indicated that the decrease of FRT (880 °C–820 °C) promoted the ferrite refinement and strain-induced precipitation in austenite, but it also led to the decrease of pearlite content, which finally led to a slight difference in properties, and CT obviously changed the phase component, grain size, and precipitation behavior. Appropriate reduction of the CT (650 °C–600 °C) could promote the precipitation of (Ti, Mo, V)C and refine ferrite grains, thus improving strength. As the CT further lowered to 550 °C, the precipitation hardening effect would be seriously lessened owing to the significant reduction of (Ti, Mo, V)C volume fraction, finally resulting in the loss of strength. The optimum mechanical properties were attained for the FRT850-CT600 sample, and the ultimate tensile strength (UTS), yield strength (YS), and total elongation (TE) were 908 MPa, 848 MPa, and 21.5 %, respectively, with precipitation hardening up to 383.51 MPa.

This study aims to analyze the distribution characteristics of energy in deeply buried circular tunnels with a revealed cave. Analytical solutions for the stress and elastic strain energies in these tunnels are derived using the complex variable method and compared with numerical solutions obtained from finite element simulations. Subsequently, a parametric study investigates the effects of the cave’s orientation, shape, and protrusion on the distribution of elastic strain energy. Finally, the influence of the revealed cave on the stability of the surrounding rock is analyzed using the evaluation index based on energy theory. The conclusions are as follows: the presence of the cave causes elastic strain energy to accumulate in the surrounding rock near the middle of the cave. The smaller the angle between the cave direction and the minimum principal stress, the more severe the energy accumulation near the cave. As the cave’s protrusion increases and the b/a ratio of its shape decreases, energy accumulation near the cave becomes more severe. The presence of the cave increases the tendency for tunnel failure. The middle of the cave is susceptible to damage due to the accumulation of strain energy, while the intersection of the cave and the tunnel is more prone to damage because tensile stresses lower the energy threshold for surrounding rock failure. The study indicates that the middle of the cave and the junction between the cave and the tunnel are key areas requiring safety protection during construction.

Abstract Background Ticks are medically important vectors capable of transmitting a variety of pathogens to and between host species. Although the spectrum of tick-borne RNA viruses has been frequently investigated, the diversity of tick-borne DNA viruses remains largely unknown. Methods A total of 1571 ticks were collected from forests and infested animals, and the diversity of the viruses they harbored was profiled using a DNA-specific virome method. The viromic data were phylogenetically analyzed and validated by PCR assays. Results Although diverse and abundant prokaryotic viruses were identified in the collected ticks, only eukaryotic DNA viruses with single-stranded circular genomes covering the anelloviruses and circular replication-associated (Rep) protein-encoding single-stranded (CRESS) DNA viruses were recovered from ticks. Anelloviruses were detected only in two tick pools, but CRESS DNA viruses were prevalent across these ticks except in one pool of Dermacentor spp. ticks. Phylogenetic analyses revealed that these tick-borne CRESS DNA viruses were related to viruses recovered from animal feces, tissues and even environmental samples, suggesting that their presence may be largely explained by environmental factors rather than by tick species and host blood meals. Conclusions Based on the results, tick-borne eukaryotic DNA viruses appear to be much less common than eukaryotic RNA viruses. Investigations involving a wider collection area and more diverse tick species are required to further support this speculation. Graphical Abstract

Radio Frequency IDentification (RFID) systems often encounter reader collisions when multiple readers interrogate tags at the same time. Especially in the mobile RFID system, the mobility of readers leads to more reader collisions. To reduce reader collisions, some centralized reader anti-collision protocols have been developed through Time Division Multiple Access (TDMA), which allows readers to interrogate tags at different time slots. As an important branch of centralized reader anti-collision protocols, the Neighbor-Friendly Reader Anti-collision (NFRA) family is able to improve the throughput of mobile RFID networks with the assistance of the polling server. This paper explores the throughput (the number of readers interrogating tags simultaneously) of five NFRA protocols including the basic NFRA protocol and four variants by using the maximum independent set. Following the classical interference model, the interference between readers can be modeled as an undirected graph in which each maximum independent vertex set corresponds to one optimal reader anti-collision solution. The contribution of this paper is to establish an evaluation framework based on maximum independent set to evaluate the performance of reader anti-collision protocols. By considering the effect of the density of readers (low, medium and high density), three groups of simulations are arranged to test the effectiveness of the evaluation framework. In addition, the performances of five NFRA protocols in different dense reader environments are studied. Simulation results indicate that the proposed evaluation method based on the maximum independent set is effective and potential in evaluating different centralized reader collision protocols.

In this study, we used 0.2C-1.7Si-1.9Mn wt% cold-rolled sheet as the experimental material to prepare the Q&P sample with blocky microstructures and the QQ&P sample with lath-shaped microstructures through the Q&P and QQ&P processes, respectively. The partitioning behavior of carbon and manganese in the two samples after intercritical annealing and partitioning were studied. During the intercritical annealing, the partitioning of carbon and manganese in the Q&P and the QQ&P samples occurred, resulting in the contents of carbon and manganese being significantly higher than those in the ferrite. Meanwhile, due to the migration of the ferrite–austenite interface during the formation of the austenite, the distributions of carbon and manganese in the lath-shaped and blocky austenite were both homogenous. The morphology of the microstructures had little influence on the distribution of carbon and manganese in metastable austenite during intercritical annealing. In the partitioning, the migration of the ferrite–austenite interface and diffusion of manganese can be ignored. Carbon first diffuses from the ferrite grains to the ferrite–austenite interface and then diffuses in the austenite grains. The morphology of the microstructures has a great effect on the homogenization of carbon in austenite grains. Compared with coarse blocky austenite, lath-shaped austenite can shorten the diffusion path of carbon in austenite grains and increase the homogeneity of carbon in austenite grains, thereby improving the thermal stability of lath-shaped austenite. Compared with the Q&P sample, the QQ&P sample has higher content of retained austenite (14.74% vs. 13.96%), better elongation (25.9% vs. 19.2%), and higher product of strength and elongation (27.5 GPa% vs. 24.4 GPa%).

This study first investigates robust iterative learning control (ILC) issue for a class of two-dimensional linear discrete singular Fornasini–Marchesini systems (2-D LDSFM) under iteration-varying boundary states. Initially, using the singular value decomposition theory, an equivalent dynamical decomposition form of 2-D LDSFM is derived. A simple P-type ILC law is proposed such that the ILC tracking error can be driven into a residual range, the bound of which is relevant to the bound parameters of boundary states. Specially, while the boundary states of 2-D LDSFM satisfy iteration-invariant boundary states, accurate tracking on 2-D desired surface trajectory can be accomplished by using 2-D linear inequality theory. In addition, extension to 2-D LDSFM without direct transmission from inputs to outputs is presented. A numerical example is used to illustrate the effectiveness and feasibility of the designed ILC law.

This paper studies the microstructures and mechanical properties of quenching and partitioning (Q&P) samples prepared with 35% and 75% cold reduction sheets at an annealing temperature of 810 °C (intercritical temperature). The results indicate that prior cold reduction could significantly influence the ferrite recovery and recrystallization during intercritical annealing, which changes the size and distribution of the ferrite and retained austenite in the Q&P samples. Compared with the 75%—Q&P sample, the 35%—Q&P sample had smaller recrystallized ferrite and retained austenite grains, a higher volume fraction of retained austenite, and a more uneven size distribution of retained austenite. The 35%—Q&P sample presented better total elongation and a higher product of strength and elongation (PSE) than the 75%—Q&P sample. The higher total elongation was related to the higher content and uneven size distribution of retained austenite for they strengthened the TRIP effect and improved the uniform elongation of the sample. The results proved that Q&P steel prepared with a cold-rolled sheet with lower reduction exhibits a better combination of strength and plasticity due to the fact that lower reduction can delay the growth rate of austenite and recrystallized ferrite grains during the intercritical annealing stage.

Staphylococcus aureus (S. aureus) infections are a leading cause of death by an infectious agent. Survival within host phagocytic cells is one mechanism by which S. aureus evades antibiotic treatment. A novel THIOMAB™ antibody-antibiotic conjugate (TAC) strategy was developed to kill S. aureus intracellularly and mitigate the spread of infection. In this report, we used a longitudinal whole-body bioluminescence imaging method to study the antibacterial dynamics of TAC alone or in combination with vancomycin in a mouse infection model. Injections of stably luminescent S. aureus bacteria into mice resulted in exponential increases in whole body bioluminescence with a reduction in body weight and survival rate. Vancomycin, a standard-of-care antibiotic, suppressed bacterial growth in mice. However, bacterial growth rebounded in these animals once treatment was discontinued. In contrast, single dose of TAC showed rapid reduction of bioluminescence intensity, which persisted for up to 19 days. The combination of TAC and vancomycin achieved a more sustained and significantly greater reduction of bioluminescence compared with vancomycin alone. In summary, the present study showed an imaging method to longitudinally assess antibacterial drug dynamics in mice and demonstrated that TAC monotherapy or in combination with vancomycin had superior and sustained activity compared to vancomycin alone.

In this paper, the effect of cold deformation on the microstructures and mechanical properties of 316LN austenitic stainless steel (ASS) was investigated. The results indicated that the content of martensite increased as the cold rolling reduction also increased. Meanwhile, the density of the grain boundary in the untransformed austenite structure of CR samples increased as the cold reduction increased from 10% to 40%, leading to a decreased size of the untransformed austenite structure. These two factors contribute to the improvement of strength and the decrease of ductility. High yield strengths (780–968 MPa) with reasonable elongations (30.8–27.4%) were achieved through 20–30% cold rolling. The 10–30% cold-rolled (CR) samples with good ductility had a good strain hardening ability, exhibiting a three-stage strain hardening behavior.

Candida albicans is a prevalent fungal pathogen amongst the immunocompromised population, causing both superficial and life-threatening infections. Since C. albicans is diploid, classical transmission genetics can not be performed to study specific aspects of its biology and pathogenesis. Here, we exploit the diploid status of C. albicans by constructing a library of 2,868 heterozygous deletion mutants and screening this collection using 35 known or novel compounds to survey chemically induced haploinsufficiency in the pathogen. In this reverse genetic assay termed the fitness test, genes related to the mechanism of action of the probe compounds are clearly identified, supporting their functional roles and genetic interactions. In this report, chemical-genetic relationships are provided for multiple FDA-approved antifungal drugs (fluconazole, voriconazole, caspofungin, 5-fluorocytosine, and amphotericin B) as well as additional compounds targeting ergosterol, fatty acid and sphingolipid biosynthesis, microtubules, actin, secretion, rRNA processing, translation, glycosylation, and protein folding mechanisms. We also demonstrate how chemically induced haploinsufficiency profiles can be used to identify the mechanism of action of novel antifungal agents, thereby illustrating the potential utility of this approach to antifungal drug discovery.