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Abstract To address the issues of poor detection accuracy and the large number of target detection model parameters in existing AGV monocular vision location detection algorithms, this paper presents an AGV vision location method based on Gaussian saliency heuristic. The proposed method introduces a fast and accurate AGV visual detection network called GAGV-net. In the GAGV-net network, a Gaussian saliency feature extraction module is designed to enhance the network’s feature extraction capability, thereby reducing the required output for model fitting. To improve the accuracy of target detection, a joint multi-scale classification and detection task header are designed at the stage of target frame regression to classification. This header utilizes target features of different scales, thereby enhancing the accuracy of target detection. Experimental results demonstrate a 12% improvement in detection accuracy and a 27.38 FPS increase in detection speed compared to existing detection methods. Moreover, the proposed detection network significantly reduces the model’s size, enhances the network model’s deployability on AGVs, and greatly improves detection accuracy.

Affected by complex operating conditions and working characteristics of the hydraulic system, hydraulic excavators suffer from large energy consumption, low energy utilization rate, and poor emissions for a long time. To improve the energy utilization efficiency and reduce the energy consumption of hydraulic excavators, a novel boom potential energy regeneration system (BPERS) for hybrid hydraulic excavators is proposed. Firstly, the structure and the working principle of the BPERS are explained, while a conventional boom-driving system (CBS) and an energy alternate recovery and utilization system (EARUS) are presented for comparison. Secondly, the mathematical model is established according to the system structure, following which the influence of the key component parameters on the energy-saving efficiency of the BPERS is analyzed. Then, an Amesim simulation model for both BPERS and CBS is established. The simulation results show that about 79.1% of boom potential energy can be recovered by the BPERS in the boom descends process, while the comprehensive energy-saving efficiency is 54.6% in a complete boom lowering and lifting process. Finally, a 50t hybrid hydraulic excavator test prototype is constructed, and the comparative experiments demonstrate that the BPERS significantly reduces the output energy of the main pump from 1039KJ to 576.1KJ in a certain working cycle, resulting in a comprehensive energy-saving efficiency of approximately 44.6%, which further confirmed the feasibility and outstanding energy-saving performance of the proposed method.

With the development of the aquaculture industry for high efficiency, energy saving, and environmentally friendly methods, recirculating aquaculture has attracted increasing attention from researchers and practitioners. A recirculating aquaculture system (RAS) consists primarily of an aquaculture module and a water purification module. In the aquaculture module, nitrogen in the feed could be released into the water phase through various routes (i.e., the feedstuff residue and aquaculture animal excretion), whose species can be transformed by microbes. Free ammonia and nitrite have acute toxic effects on aquaculture animals, rendering the efficient removal of ammonia and nitrite essential for the RAS. Compared with physical and chemical methods, biological treatment methods based on microbial nitrification can convert ammonia and nitrite into less toxic nitrate with the advantages of good treatment performance, low operation cost, and little secondary contamination, and have been widely utilized in the purification of multiple wastewaters (e.g., municipal wastewater, industrial wastewater, agricultural wastewater, and ammonia-contaminated groundwater). For the treatment of recirculating water with low and fluctuating nitrogen loads, a biofilm process based on the attached growth of microbes is more suitable than an activated sludge process based on the suspended growth of microbes. To date, a variety of biofilm processes have been developed, among which the fixed-bed biofilm reactor (FBBR) and moving-bed biofilm reactor (MBBR) have been widely investigated for the control of ammonia and nitrite in aquaculture wastewater. However, the relevant studies were mostly conducted in laboratory- and pilot-scale RASs. Thus, there is still a lack of comparative investigations of FBBR and MBBR, which are simultaneously operated in a full-scale RAS.Therefore, a parallel FBBR and MBBR were joined to a full-scale RAS for Macculochella peeli. The FBBR and MBBR were simultaneously and continuously operated for 35 d to investigate variations in their water quality and microbial community structures. The results indicate that the FBBR and MBBR had similar variations in ammonia, nitrite, nitrate, and pH in the effluents. Over the entire operational period, the dissolved inorganic nitrogen (DIN) concentrations gradually increased; the ammonia and nitrite concentrations and their proportions in DIN first increased and then decreased stepwise; and the nitrate concentrations increased gradually, while the variation in the nitrate proportions in DIN was opposite to that of ammonia and nitrite. Both the FBBR and MBBR could transform ammonia and nitrite to nitrate, which resulted in nitrate accumulation and a pH decrease in aquaculture water. During the operation period, the nitrification capacity gradually matured, and ammonia oxidation could occur prior to nitrite oxidation. At 35 d, the concentrations of ammonia, nitrite and nitrate were 0.32 (0.29), 0.27 (0.22) and 29.75 (29.76) mg/L with their proportions in DIN of 1.05% (0.96%), 0.90% (0.72%) and 98.05% (98.32%) in FBBR (MBBR) effluent; pH declined from7.62 (7.59) to 7.25 (7.22) in FBBR (MBBR) effluent.The number of operational taxonomic units (OTU) obtained from the FBBR and MBBR samples were 2, 088 and 1, 852, respectively, and 1, 174 OTUs were shared between FBBR and MBBR. The α indices (Chao1, ACE, Shannon, and Simpson) from the biofilm reactors indicated that FBBR possessed higher richness and diversity of the microbial community than MBBR, which could be attributed to the difference in the internal environment between FBBR and MBBR. In total, 16 phyla, 28 classes, and 149 genera were identified in the FBBR samples, which were slightly fewer than those from the MBBR samples (i.e., 19 phyla, 31 classes, and 155 genera). However, the relative abundance of microbes demonstrated that FBBR and MBBR had similar predominant microbes: Proteobacteria (69.42% in FBBR and 86.92% in MBBR) at the phylum level, γ-Proteobacteria (40.71% in FBBR and 64.36% in MBBR) and α-Proteobacteria (26.58% in FBBR and 21.74% in MBBR) at the class level, and Acinetobacter (27.50% in FBBR and 53.29% in MBBR) at the genus level. Nitrosomonas and Nitrospira constituted the nitrifiers in both FBBR and MBBR, but the relative abundance of nitrifiers was higher in FBBR. Furthermore, the relative abundance of Nitrospira was far higher than that of Nitrosomonas, indicating that complete ammonia oxidation bacteria might exist in FBBR and MBBR. In addition, Vibrio was not found in FBBR and MBBR, but Bdellovibrio was observed. The results of this study can provide technical support for the selection of biological purification technology for RAS, and thus improve the green development of the aquaculture industry.Future studies will focus on: Investigating the effects of water quality conditions and operational parameters on the water treatment performance of FBBR and MBBR; Determining the species of complete ammonia oxidation bacteria and their relative abundances on the filler surface in FBBR and MBBR; Effectively eliminating nitrate in the aquaculture water by introducing microbial denitrification process after FBBR and MBBR to control the total nitrogen in RAS; Establishing a flexible and feasible strategy for controlling the pH in recirculating water by exploring the solid-phase buffers that could serve as the slow-release sources of alkalinity in the biofilm reactor.

Embedded Mask Patterning (EMP) has been proposed as a cost-effective fabrication method to be capable of patterning sub-5-nm grain sizes for highly ordered L10-FePt media for Heat-Assisted Magnetic Recording (HAMR). Understanding the etching mechanism of FePt is critical to maintaining the highly ordered L10 structure and low damage to magnetic grains. In this research, a reactive Molecular Dynamics (MD) model is developed to study methanol (MeOH) plasma etching on highly ordered continuous L10-FePt media film. The model describes the reactive interaction mechanism between the plasma products CO/H2 molecules and Fe/Pt atoms. It shows the dominant Fe-C interaction upon the dissociation of CO ligands leads to formation of large and volatile Fen-C clusters contributing to high chemical etch yield.

Atomic structures of α″-phase magnetic material C-doped Fe16N2−nCn [n = (0,2)] are investigated using molecular dynamics energy minimization method. Based on simulated annealing principles, a highly efficient search method is developed to find the approximation to “global” minimum energy states for these ternary bct lattice structures by sampling a series of local energy minimal from continuously divided minimization space. It is found that in Fe16N2−nCn alloy, although lattice parameters vary with C concentration, bond length rankings of C/N-Fe at Wyckoff positions are consistent with those in Fe16C2 and Fe16N2 phases. There are also existing Fe16N2−nCn alloys with high-C concentrations (C:N ≥ 1) showing higher stability than Fe16C2 and Fe16N2.

Litopenaeus vannamei is one of the most important species of cultured shrimp in China. With the continuous development of intensive culture and increase in stocking density and feed feeding, the yield of cultured shrimp and utilization rate of the cultured environment have improved rapidly. However, a large number of residual baits, feces, fertilizers, and drugs have worsened the aquaculture water environment and led to prominent adverse environmental effects, widespread aquatic animal diseases, and severe environmental pollution. Therefore, the development of pollution-free ecological aquaculture, the promotion of industrialized circulating water aquaculture, and the research of efficient and sustainable biological purification systems have become the focus of aquaculture model research. Circulating water aquaculture is a new aquaculture mode in which water is treated and reused using modern techniques.To explore aquaculture water quality and the composition structure of microbial flora in an industrialized circulating water aquaculture system of L. vannamei, the water quality indexes of biological purification aquaculture systems such as primary moving bed biological purification, secondary fixed-bed biological purification, and aquaculture water, and the microbial flora of water and shrimp intestines were measured using high-throughput sequencing technology and bioinformatics analysis. The experimental results showed that the mass concentrations of ammonia nitrogen (NH4+-N) and nitrite nitrogen (NO2–-N) in the culture water met the standards for the healthy culture of L. vannamei after treatment with the biological purification culture system. Concentrations are 0.85 and 0.21 mg/L. Results showed that all water and carrier samples contained a certain abundance of nitrifying Spirillum bacteria, especially on the biological purification carrier, which was significantly higher than the proportion of the bacterial community in water samples. The Chao1 and Shannon indices of chemical fiber filament biological carriers were significantly higher than those in shrimp intestines. Results also showed that the number of microbial species and microbial community diversity on the biological carrier of chemical fiber filaments were higher than those in the intestine of shrimp. The bacterial community composition was characterized at the phylum and genus levels. A total of 46 bacterial phyla were identified in the samples. Proteobacteria, Bacteroidetes, and Actinobacteria were the dominant phyla in the water, and Proteobacteria, Bacteroidetes, Actinobacteria, and Planctomycetes were the dominant phyla in the biological carrier; Proteobacteria, Bacteroidetes, and Firmicutes were the dominant phyla in the shrimp intestine. The abundance of Planctomycetes in the biological carriers increased. The abundance of Proteobacteria and Firmicutes in shrimp intestines was higher than that in water, conducive to the degradation of nitrogen and phosphorus. Bacteroidetes and Firmicutes were the main metabolizing bacteria in the intestine, promoting carbohydrate metabolism and energy acquisition in shrimp. Actinobacteria can degrade organics, including macromolecules such as starch and proteins, and produce antibiotics and other antibacterial substances. The abundance of Actinobacteria in water was very high but decreased in shrimp, which played an important role in the decomposition of organic matter and nitrogen in water. The bacterial species content in the biological purification carrier of the shrimp culture circulating system was lower than that in the water sample, but the microbial diversity was higher than that of aquaculture water. The microorganisms in the biological purification carrier have the characteristics of low abundance and high diversity, possibly due to the increase in the abundance of environment-related functional bacteria on the biological purification carrier and the decrease in some flora species with little impact on the environment, resulting in the aggregation of biofilm bacteria species. In addition, the water and biological purification carrier also contained a certain amount of pathogenic bacteria, such as Vibrio and Mycobacterium. Therefore, it was necessary to regulate the content of pathogenic bacteria in the water environment and shrimp intestine to ensure a healthy shrimp culture. The results showed that the multi-stage biological purification system can effectively increase the microbial flora, promote the metabolism of nitrogen and phosphorus in the water, and regulate the quality of the aquaculture water. The dominant bacterial groups in water, biological purification carriers, and shrimp were different. Proteobacteria and Bacteroidetes were dominant in water biological carriers and intestines, whereas Planctomycetes mainly exist as biological carriers, Firmicutes mainly colonize the intestine, and Actinomycetes mainly exist in water. In this study, high-throughput sequencing technology was used to study the composition of the microbial community structure in the circulating water culture system of L. vannamei. Results can reveal the diversity of its internal microbial community, provide a basis for further revealing the "black box" of biofilters, and have important guiding significance for the study of the construction and denitrification efficiency of biofilters in seawater circulating water culture.

The chemical industry is a major carbon emitter in China and must be focused on for China to achieve its goal of carbon neutralization. Carbon dioxide (CO2) high-temperature electrolysis based on solid oxide electrolysis cells (SOECs) is an important technology to achieve China’s carbon emission reduction, peak carbon emission, and carbon neutralization goals. Moreover, this technology can realize the recycling utilization of CO2 and thereby contribute to considerable environmental benefits and potential economic benefits. Thus far, a great deal of progress has been made in CO2 high-temperature electrolysis technology at the laboratory stage and pilot stage, although the large-scale industrial application of this technology still requires further development. This review focuses on recent progress in state-of-the-art cell materials for high-temperature CO2 electrolysis, discusses the future research directions of SOEC technologies, and proposes possible SOEC-coupled chemical industry carbon neutralization solutions.

To investigate the difference in aroma between high aroma black tea and traditional congou black tea, electronic nose and GC-MS were used to investigate the key factors that differentiated the aroma quality of high aroma black tea from traditional congou black tea. The results showed that the high aroma black tea had a predominantly floral aroma, while the traditional congou black tea aroma presented a sweet aroma. GC-MS detected 78 volatile substances in the two black teas, among which linalool oxide, linalool, methyl salicylate, pentanol, 2-cyclopropylethanol, (-)-carveol, β-cyclocitral, 2-ethylfuran, 1,3,8-menthatrien and 1,4-pentadiene were important aroma components to distinguish the different flavours of black tea. The total of the response values of the electronic nose detection of traditional congou black tea was significantly higher than that of high aroma black tea. The multivariate statistical analysis allowed S6 and S10 electrode signals for the identification of different flavours of black tea, and predicted that 1,4-pentadiene was an important volatile substance for the identification of different flavours of black tea. The results confirmed the aroma composition characteristics of high fragrant black tea and distinguished it from traditional congou black tea, and would provide a theoretical basis for further classification of different flavor black tea.

Background: s: Acute myeloid leukemia (AML) is a malignant tumor of the hemopoietic system in adults. Although multiple signaling pathways are associated with this disease, its pathogenesis has not yet been fully elucidated. Herein, we aimed to explore the novel prognostic, diagnostic and therapeutic targets in patients with AML. Methods: Gene expression, overall survival (OS) and diagnosis were analyzed by bioinformatics software with The Cancer Genome Atlas (TCGA) database and our cohort population (52 healthy subjects and 98 AML patients). Results: Three prognostic factors T-cell leukemia translocation-altered gene (TCTA), sideroflexin 3 (SFXN3) and phospholipase A2 group IVA (PLA2G4A) were closely linked to poor prognosis in patients with AML based on the TCGA database and our cohort population. Multivariate COX regression analysis indicated that age (>60 years), up-regulation of SFXN3 and PLA2G4A were the independent prognostic factors associated with poor OS. Intriguingly, TCTA, SFXN3 and PLA2G4A presented the remarkable diagnostic value to distinguish AML from healthy subjects. Knockdown of SFXN3 led to inhibition of AML cell growth in vitro and in vivo and prolonged the survival time of nude mouse. Conclusion: A three-gene panel may play pivotal pathogenic roles in AML, represents potential prognostic and diagnostic indicators and therapeutic targets in the patients with AML. In addition, SFXN3 may be a potential therapeutic target of AML.

α″-Fe16N2 is a promising environmentally friendly rare-earth-free permanent magnet material with ultra-high saturation magnetization. Recent research has demonstrated experimentally through a thermally quenching treatment using γ′ phase Fe4N as a precursor to synthesize α″-Fe16N2 in bulk format. In this research using Molecular Dynamics (MD) simulation, we investigated the γ′-Fe4N phase thermal decomposition process and the potential phase transition from face center cubic (fcc)-phase to body center tetragonal (bct)-phase. As nitrogen concentration is higher in γ′-Fe4N (5.9 wt. %) than that in α′-Fe8N or α″-Fe16N2 (3 wt. %), Nitrogen bond formation through atom diffusion is studied with a “Nitrogen-rich” grain boundary (GB) model to find out whether lower-Nitrogen content bct Fe–N solid solution can be formed. Modified Embedded Atom Method (MEAM) interatomic potential of Fe–N system is applied. Post-processing including Nitrogen bond mapping/tracking is also performed for the thermostat-controlled heating and quenching simulation process. We also applied virtual XRD computation to characterize the material crystallographic texture before and after the thermal treatment.

Aggregate stability is considered an essential indicator of changes in the physical properties of soils, and vegetation roots play a crucial role in the stability of shallow soil aggregates in ionic rare earth tailings piles during ecological remediation. In this paper, the influence of the law of ecologically restored vegetation roots on the stability of shallow aggregates of ionic rare earth tailing piles was investigated by means of field investigation tests, indoor experiments and mathematical statistics. The influence of different types of root systems on the stability of the shallow depth range aggregates of tailings piles was investigated; the correlation between vegetation root systems and the main physical parameters of rare earth tailings was clarified; and a mathematical correlation model characterizing the characteristic parameters of vegetation root systems was constructed. The evaluation index of the stability of rare earth tailings piles was constructed, and the influence of the law of the ecological restoration of vegetation root systems on the strength of shallow aggregates of ionic rare earth tailings piles was revealed. The results of the study showed that compared with the RD (root density), the root characteristic parameter with the largest response weight to the rare earth tailings pile is the RL (root length density), and the root characteristic parameter with the largest response weight to the water content is the RV (root volume). Suitable vegetation roots can effectively enhance the content of shallow large aggregates of rare ionic earth tailing piles. With the increase of the depth of a tailing pile, the content of large aggregates continues to decrease, and the content of micro aggregates continues increasing. This indicates that the vegetation root system changed the shallow soil of the rare earth tailing pile from disorderly to orderly through its own growth pattern, which effectively improved the stability of the shallow aggregates of the tailing pile and improved the physical properties of the tailing.

Instantaneous hardware protection is a very important method to protect inverters at the moment of over current or short circuit fault. For standalone inverters, the hardware protection can also be modified to achieve current limiting during the over current or short-circuit period. In conventional cycle by cycle (CBC) current protection, all switches of the inverter are turned OFF immediately when current is higher than the over current threshold. However, it may lead to protection being triggered frequently and high di/dt in switches and diodes, which will do harm to the reliability of the inverter. To solve this issue, a new CBC current limiting method is proposed, which turns off partial switches of the inverter. The operation principle of the conventional method and the presented method are detailed analyzed with switching states and implementation circuits given. In addition, the presented method is verified by an engineering prototype, and experimental results verified the effectiveness of the proposed method.

The performance of the process network in the smart substation is particularly important for relaying functions implementation, and the transmission quality of sampled value packets is becoming the key constraint on protections because they carry practical parameters of the power system without repeated transmission. By means of phasor form and simulation, the model is built to analyze the operating characteristics of differential protection during the normal condition, external faults, and internal faults of the transformer, while packet loss/delay occurring at a different time and using different corrective measures. Considering the change of power equipment capacity, external fault types, starting points on wave and sampling frequency, the security boundaries are constructed for consecutive loss of sampled value packets. In addition, two indices are put forward to weigh the tolerance thresholds. Finally, the degree of dependability of differential protection due to the packet loss is further analyzed under the transformer internal faults.

The noise of a cab directly affects the comfort and labor efficiency of the operators. The optimization of the structure-borne transmission path can obviously reduce the cab noise. The method of panel acoustic contribution analysis (PACA) is used to reduce structure noise. However, most studies only consider the panel acoustic contribution of a single frequency, without considering the contribution of major frequencies synthesis to confirm the optimized panels. In this paper, a novel method is proposed based on composite panel acoustic and modal contribution analysis and noise transfer path optimization in a vibro-acoustic model. First, the finite element model (FEM) and the acoustic model are established. Based on the acoustic transfer vector (ATV) method, a composite panel acoustic contribution analysis method is proposed to identify the panels affecting the noise of the field point. Combined with the modal acoustic contribution of the modal acoustic transfer vector (MATV) method, the noise field point is confirmed in the area which has the most significant influence. Second, the optimization algorithm NLOPT which is a nonlinear optimization is applied to design the areas. The noise transfer path optimization with vibroacoustic coupling response can quickly determine the optimal thickness of the panels and reduce low-frequency noise. The effectiveness of the proposed method is applied and verified in an excavator cab. The sound pressure level (SPL) the driver’s right ear (DRE) decreased obviously. The acoustic analysis of the composite panel acoustic contribution and modal acoustic contribution can more accurately recognize an optimized area than the traditional PACA. This method can be applied in the optimization of the structure-borne transmission path for construction machinery cab and vehicle body.

A novel porous heterostructured Nd0.8Sr1.2CoO4±δ/Nd0.5Sr0.5CoO3-δ (NSC214/113) cathode for intermediate temperature solid oxide fuel cells (IT-SOFCs) is developed to significantly enhance oxygen reduction reaction (ORR) kinetics. Compared to single-phase materials, the fabricated porous heterostructured NSC214/113 shows optimized electrochemical properties, including a better conductivity, 20 times faster surface oxygen exchange kinetics, and a comparatively lower area-specific resistance (0.065 Ω cm2 at 800 °C). The single cell with Ni-YSZ|YSZ-GDC|NSC214/113 configuration exhibits a high peak power density of 1.10 W cm−2 at 800 °C, superior to other cells reported in literature with similar heterostructured cathodes. Moreover, the underlying mechanism of the ORR performance enhancement is further investigated, revealing that the formation of heterojunction can lead to a narrowed energy bandgap and a decrease of Co oxidation state, which further induce better conductivity, more available electrons and oxygen vacancies to enhance the ORR process. Taken together, our research also provides new insights into potential application of artificial intelligence (AI) method involved in materials intelligent identification, cell state estimation, system diagnostic and optimization. The revolutionary force of AI, especially in the field of new electrode material development is now advancing in its full swing. More and greater breakthroughs are still expected.

Abstract Background Work-place exposure to silica dust may lead to progressive lung inflammation culminating in the development of silicosis, an irreversible condition that can be complicated by onset of pulmonary hypertension (PH). The molecular mechanisms leading to the development of PH and lung fibrosis in response to silica are not well understood. Oxidant/antioxidant imbalance in the lung may promote fibroproliferation and vascular smooth muscle proliferation, ultimately leading to the development of PH. Herein, we analyze the development of PH and lung fibrosis in mice deficient in extracellular superoxide dismutase (SOD3), an enzyme with anti-oxidant activity. Methods PH and silicosis were induced in wild-type and Sod3−/− mice through intratracheal injection of crystalline silica at dose 0.4 g/kg. Pulmonary hypertension and lung fibrosis were characterized by changes in right ventricular systolic pressure (RVSP) and collagen deposition 28 days following silica injections. Vascular remodeling was analyzed using immunohistochemistry and morphometric analysis. The expression of genes were analyzed using qRT-PCR and Western blot. Results C57BL6 mice exposed to silica showed attenuated expression of Sod3 in the lung suggesting a protective role for Sod3. Consistent with this, Sod3−/− mice developed more severe fibrotic inflammatory nodules with increased collagen deposition. Furthermore, the expression of genes involved in tissue remodeling (Timp1), fibrotic lesion formation (Fsp1) and inflammatory response (Mcp1) were significantly elevated in Sod3−/− mice compared to Sod3+/+ mice treated with silica. Infiltration of neutrophils and activated macrophages into affected lung was significantly higher in Sod3 deficient mice. In addition, silica produced more profound effects on elevation of RVSP in Sod3−/− compared to wild-type littermate. Increase in RVSP was concomitant with hypertrophy of pulmonary arteries located in silicotic nodules of both mouse strains, however, vascular remodeling in unaffected areas of lung was detected only in Sod3−/− mice. Conclusions Our data suggest that Sod3 and extracellular oxidative stress may play an important role in the development of pneumoconiosis and pulmonary vascular remodeling following exposure to environmental and occupational silica.

The Industrial Internet of Things (IIoT) has become a pivotal field of development that can increase the efficiency of real-time collection, recording, analysis, and control of the entire activities of various machines, and can actively enhance quality and reduce costs. The traditional IIoT depends on centralized architectures that are vulnerable to several kinds of cyber-attacks, such as bottlenecks and single points of failure. Blockchain technology has emerged to change these architectures to a decentralized form. In modern industrial settings, blockchain technology is utilized for its ability to provide high levels of security, low computational complexity, P2P communication, transparent logs, and decentralization. The present work proposes the use of a private blockchain mechanism for an industrial application in a cement factory, which offers low power consumption, scalability, and a lightweight security scheme; and which can play an efficient role in controlling access to valuable data generated by sensors and actuators. A low-power ARM Cortex-M processor is utilized due to its efficiency in terms of processing cryptographic algorithms, and this plays an important part in improving the computational execution of the proposed architecture. In addition, instead of proof of work (PoW), our blockchain network uses proof of authentication (PoAh) as a consensus mechanism to ensure secure authentication, scalability, speed, and energy efficiency. Our experimental results show that the proposed framework achieves high levels of security, scalability and ideal performance for smart industrial environments. Moreover, we successfully realized the integration of blockchain technology with the industrial internet of things devices, which provides the blockchain technology features and efficient resistance to common cyber-security attacks.

In this paper, a solution is provided to solve the heat conduction equation in the three-dimensional cylinder region, where the laser intensity of the material irradiation surface is expressed as a Gaussian distribution. Based on the symmetry of heat distribution, firstly, the form of the heat equation in the common rectangular coordinate system is changed to another form in the two-dimensional cylindrical coordinate system. Secondly, the ADI with the backward Euler method and with Crank–Nicolson method are established to discretize the model in the cylindrical coordinate system, after which the simulation results are obtained, where the first kind of boundary value condition is used to verify the accuracy of these two algorithms. Then, the above two methods are used to solve the model with the third kind of boundary value condition. Finally, the comparison is performed with the results obtained by the MATLAB’s PDETOOL, which shows that the solution is more feasible and efficient.

Abstract A Cr3+ and F− composite-doped LiNi0.5Mn1.5O4 cathode material was synthesized by the solid-state method, and the influence of the doping amount on the material’s physical and electrochemical properties was investigated. The structure and morphology of the cathode material were characterized by XRD, SEM, TEM, and HRTEM, and the results revealed that the sample exhibited clear spinel features. No Cr3+ and F− impurity phases were found, and the spinel structure became more stable. The results of the charge/discharge tests, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) test results suggested that LiCr0.05Ni0.475Mn1.475O3.95F0.05 in which the Cr3+ and F− doping amounts were both 0.05, had the optimal electrochemical properties, with discharge rates of 0.1, 0.5, 2, 5, and 10 C and specific capacities of 134.18, 128.70, 123.62, 119.63, and 97.68 mAh g−1 , respectively. After 50 cycles at a rate of 2 C, LiCr0.05Ni0.475Mn1.475O3.95F0.05 showed extremely good cycling performance, with a discharge specific capacity of 121.02 mAh g−1 and a capacity retention rate of 97.9%. EIS test revealed that the doping clearly decreased the charge-transfer resistance.

Plastic deformation at room temperature, and the proceeding heat treatments, are important processes for optimizing the microstructure and mechanical properties of austenitic stainless steel. The microstructure and mechanical properties of cold-drawn 304 austenitic stainless steel wire were investigated after annealing at 700 °C and 800 °C, with different times (20, 40 and 60 min) and drawing strain (0.4, 1.0 and 1.5). Electron backscattered diffraction (EBSD) techniques, transmission electron microscope (TEM) analysis, differential scanning calorimeter (DSC) and tensile tests were performed in order to study the microstructure evolution and mechanical properties during different annealing processes for the 304 austenitic stainless steel wire. The results showed that the quantity of α ′ martensite and dislocations increased with an increase in the strain, which means that, while the ultimate tensile strength of the cold-drawn wires elevated, the elongation reduced. The mechanical properties of stainless steel wires also varied with the evolution of martensite transformation characteristics, density of stacking fault, dislocation and twin, as well as the recrystallization degree under various annealing conditions. The recrystallization temperature of steel wire was mainly determined by the magnitude of the strain, while the martensite reversal temperature was determined by the stacking fault energy and the deformation value. The temperature of recrystallization and martensite reverse in steel wire decreased with the increment of the strain. The balance of tensile strength and elongation of steel wire can be obtained by adopting the proper annealing process combined with cold-drawing deformation. In this paper, we showed that a good combination of strength and elongation in 304 austenitic stainless steel can be obtained with a strain of 1.5 annealed at 800 °C for 20 min.

The micro/macro magnetic properties, local element distribution, martensite transformation, and mechanical properties of 304H stainless wires are determined for two cold drawing chains. Finite element simulations are used to analyse the local strain and heat generation. The results show that there is obvious inhomogeneity in the magnetic properties, strain/stress relationship, and strain-induced heat within the drawn wires. Comparing wires with the same total strain, a larger area reduction of previous drawing processes contributes to a higher volume of the martensite phase, while a smaller area reduction of the first process results in an inhibited phase transformation. A higher single strain in the first drawing process leads to additional heat generation at the subsurface of the wire, which would eventually retard the martensite transformation. The inhomogeneous deformation-induced differences in the grain size affect the stability of austenite and transform the final martensite.

High power cylindrical Ni-MH battery cells have a heavy heat load because of their high discharge rate and large equivalent internal resistance. This heavy heat load, together with an imbalanced flow in parallel liquid cooling systems, can lead to variances in the temperature of each cell in the entire battery pack, thereby reducing the life cycle of the battery pack. In this paper, a parallel-series combined liquid cooling system for a 288V Ni-MH battery pack was designed, and several parameters that influence the flow balance of the system by heat transfer and fluid dynamics were calculated. Then, a thermal-fluid simulation was executed with different parameters using StarCCM+ software, and the simulation results were validated by a battery pack temperature experiment on a bench and in a vehicle. The results indicate that the cell’s temperature and temperature differences can be kept within an ideal range. We also determined that within the battery power requirements and structural spacing limits, the total flow rate of the cooling liquid, the cross-sectional area ratio of the main pipe to the branch pipes, and the number of internal supporting walls in each branch pipe need to be large enough to minimize the cell’s maximum temperature and temperature differences.

Plasma etching process of single-crystal L10-FePt media [H. Wang et al., Appl. Phys. Lett. 102(5) (2013)] is studied using molecular dynamic simulation. Embedded-Atom Method [M. S. Daw and M. I. Baskes, Phy. Rev. B 29, 6443 (1984); X. W. Zhou, R. A. Johnson and H. N. G. Wadley, Phy. Rev. B 69, 144113 (2004)] is used to calculate the interatomic potential within atoms in FePt alloy, and ZBL potential [J.F. Ziegler, J. P. Biersack and U. Littmark, “The Stopping and Range of Ions in Matter,” Volume 1, Pergamon,1985] in comparison with conventional Lennard-Jones “12-6” potential is applied to interactions between etching gas ions and metal atoms. It is shown the post-etch structure defects can include amorphized surface layer and lattice interstitial point defects that caused by etchant ions passed through the surface layer. We show that the amorphized or damaged FePt lattice surface layer (or “magnetic dead-layer”) thickness after etching increases with ion energy for Ar ion impacts, but significantly small for He ions at up to 250eV ion energy. However, we showed that He sputtering creates more interstitial defects at lower energy levels and defects are deeper below the surface compared to Ar sputtering. We also calculate the interstitial defect level and depth as dependence on ion energy for both Ar and He ions. Media magnetic property loss due to these defects is also discussed.

Light-emitting diode (LED) has higher efficiency and longer lifetime when compared with the conventional lighting. However, the efficiency and lifetime will be degraded greatly when it is operated at a high temperature. Now, both previous simulation and experimental results have already indicated that the heat transfer in vertical direction of the LED lamp by conduction is the most critical component. In this paper, a simplified numerical simulation model is built to estimate the heat distribution of the LED heat sink in the spherical coordinate system, which would be useful for its shape optimization design. With this model, some mathematical treatments are provided to a heat conduction equation, in order to rapidly compute the static heat distribution and the temperature of different designs of LED heat sinks. The built rapid heat sink evaluation method, implicit finite difference method (IFDM), is unconditionally stable. Several heat distribution simulations could demonstrate that our built mathematical model conforms well to the reality and our method is full of feasibility and effectiveness.

Bone marrow stromal cells (BMSCs) may differentiate into nerve cells under a certain condition; however, the clinical application for treating nervous system disease remains unclear. The aim is to assess the safety profile, feasibility, and effectiveness of surgery combined with autologous BMSCs transplantation for treating ICH. 206 ICH patients who had received surgical procedure were divided into transplantation (n=110) or control group (n=96). For transplantation group, BMSCs were injected into the perihemorrhage area in the base ganglia through an intracranial drainage tube 5.5 (3.01–6.89) days after surgery, followed by a second injection into the subarachnoid space through lumbar puncture 4 weeks later. Neurologic impairment and daily activities were assessed with National Institute Stroke Scale (NIHSS), Barthel index, and Rankin scale before transplantation and 6 months and 12 months after transplantation. Our results revealed that, compared with control group, NIHSS score and Rankin scale were both significantly decreased but Barthel index was increased in transplantation group after 6 months. Interestingly, no significant difference was observed between 12 months and 6 months. No transplantation-related adverse effects were investigated during follow-up assessments. Our findings suggest that surgery combined with autologous BMSCs transplantation is safe for treatment of ICH, providing short-term therapeutic benefits.