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The steel industry is an important foundation of the national economy and the livelihood of the people, producing a large amount of carbon dioxide gas, accounting for about 70% of the carbon dioxide gas generated in the steel industry, which occurs during the ironmaking process. Therefore, the key technology to reduce the pollution and improve competitiveness is to increase the stability of blast furnace production and the quality of hot metal. Since the operation requirements for temperature control in the vanadium-titanium blast furnace are dramatically different compared to the traditional ones due to the low fluidity of vanadium-titanium slag, maintaining the required hot metal temperature within a narrow range with smaller fluctuations is essential. In addition, the adjustment parameters of the lower part have a significant influence on the tuyere combustion flame temperature during the daily operation of blast furnaces. At present, there is no relevant research on the online detection and analysis of vanadium-titanium blast furnace tuyere combustion flame temperature. In this study, the temperature of four tuyeres in a 500 m3 vanadium and titanium blast furnace at Jianlong Steel was detected by an online detection system. The tuyere combustion flame temperature was then calculated using colorimetric temperature measuring methodology at various times and at four distinct locations. After that, the calibration analyses, imaging parameter and the temperature tendencies in different directions of the blast furnace were investigated. This study not only offers new methods for understanding the regularity of operation and increasing the degree of visualization in vanadium and titanium smelting blast furnaces but also provides technical support for intelligent and low-carbon operation in blast furnaces. [ABSTRACT FROM AUTHOR]

4D millimeter wave (mmWave) imaging radar is a new type of vehicle sensor technology that is critical to autonomous driving systems due to its lower cost and robustness in complex weather. However, the sparseness and noise of point clouds are still the main problems restricting the practical application of 4D imaging radar. In this paper, we introduce SMIFormer, a multi-view feature fusion network framework based on 4D radar single-modal input. SMIFormer decouples the 3D point cloud scene into 3 independent but interrelated perspectives, including bird's-eye view (BEV), front view (FV), and side view (SV), thereby better modeling the entire 3D scene and overcoming the shortcomings of insufficient feature representation capabilities under single-view built from extremely sparse point clouds. For multi-view features, we proposed multi-view feature interaction (MVI) to exploit the inner relationship between different views by integrating features from intra-view interaction and cross-view interaction. We evaluated the proposed SMIFormer on the View-of-Delft (VoD) dataset. The mAP of our method reached 48.77 and 71.13 in the fully annotated area and the driving corridor area, respectively. This shows that 4D radar has great development potential in the field of 3D object detection. [ABSTRACT FROM AUTHOR]

Objective. To investigate the targets and mechanisms of valsartan in the treatment of chronic renal failure based on network pharmacology and animal experiment validation. Methods. The objectives of using valsartan were predicted with the PubChem and SwissTargetPrediction databases. Relevant targets of chronic renal failure have been searched in various disease databases, with the common purposes of drugs and diseases extracted. Network analysis was carried out with the STRING database to construct a protein-protein interaction (PPI) network, as Cytoscape 3.9.1 software was used to analyze network topology of the key targets and establish the "valsartan-core target gene" network. Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed on core targets to explore their possible molecular mechanisms. The chronic renal failure mouse model was established by the plat method. Hematoxylin-eosin (H&E) and Masson staining observed morphological changes in renal problems of each group, as levels of serum Cre, BUN, T-SOD, and MDA in each group were detected by kit; real-time PCR was used to detect the relative expression of mRNA of TNF-αIL-1β, IL-6, and IL-10 in renal disease of mice in each group, with WB detect CALM, PKCα, and CaMKIV protein expression levels in renal disease from each group. Results. The network pharmacology approach identified 10 key targets for treatment of chronic renal failure with valsartan, including EGFR, PTGS2, PPARG, and ERBB2. KEGG enrichment analysis predicted that the drug exerted neuroactive ligand-receptor interaction, the calcium signaling pathway, the HIF-1 signaling pathway, the proteoglycans in cancer, PD-L1 expression, and the PD-1 checkpoint pathway in cancer. Results from animal experiments were compared to those of the model group, as renal function was significantly improved in the valsartan-dose group. The serum levels of Cre, BUN, and MDA and relative mRNA expression of TNF-α, IL-1β, and IL-6 decreased significantly, while serum T-SOD levels, relative mRNA expression of IL-10, and the protein expression level of CALM, PKCα, and CaMKIV increased significantly (P < 0.05 and P < 0.001). Conclusion. Valsartan yields certain renal protection, which may improve chronic renal failure in mice through the calcium signaling pathway. [ABSTRACT FROM AUTHOR]

Engineering ethics is a system of ethical principles applied to engineering, which plays the role of value guidance and criterion evaluation in engineering construction activities. Based on engineering ethics, writers review the Sanmenxia Reservoir Project, and use system dynamics to systematically study the evolutionary game of engineering community members, including government, enterprise, and people, involved in the engineering activities. The results show that the engineering community is a heterogeneous community with complex game behaviors, and the correct ethical choice is the key factor that promotes the evolution of the community members to cooperative dynamic equilibrium. Good management of ethical commitment, emphasis on professionalism and public services, strengthening risk alert and avoidance are effective ways for members of the engineering community to form a cooperative game, avoid tragedy of public resources, and ultimately ensure the orderly development of projects.

Single-nucleotide polymorphisms in G protein-coupled receptor 180 (GPR180) are associated with hypertriglyceridemia. The aim of this study was to determine whether hepatic GPR180 impacts lipid metabolism. Hepatic GPR180 was knocked down using two approaches: Gpr180-specific short hairpin (sh)RNA carried by adeno-associated virus 9 (AAV9) and alb-Gpr180−/− transgene established by crossbreeding albumin-Cre mice with Gpr180flox/flox animals, in which Gpr180 was specifically knocked down in hepatocytes. Adiposity, hepatic lipid contents, and proteins related to lipid metabolism were analyzed. The effects of GPR180 on triglyceride and cholesterol synthesis were further verified by knocking down or overexpressing Gpr180 in Hepa1-6 cells. Gpr180 mRNA was upregulated in the liver of HFD-induced obese mice. Deficiency of Gpr180 decreased triglyceride and cholesterol contents in the liver and plasma, ameliorated hepatic lipid deposition in HFD-induced obese mice, increased energy metabolism, and reduced adiposity. These alterations were associated with downregulation of transcription factors SREBP1 and SREBP2, and their target acetyl-CoA carboxylase. In Hepa1-6 cells, Gpr180 knockdown decreased intracellular triglyceride and cholesterol contents, whereas its overexpression increased their levels. Overexpression of Gpr180 significantly reduced the PKA-mediated phosphorylation of substrates and consequent CREB activity. Hence, GPR180 might represent a novel drug target for intervention of adiposity and liver steatosis. [ABSTRACT FROM AUTHOR]

Maleic anhydride (MA) is introduced to fabricate poly(vinylidene fluoride)/expanded graphite (PVDF/EG) composites via one-step melt mixing. SEM micrographs and WAXD results have demonstrated that the addition of MA helps to exfoliate and disperse the EG well in the PVDF matrix by promoting the mobility of PVDF molecular chains and enhancing the interfacial adhesion between the EG layers and the PVDF. Thus, much higher thermal conductivities are obtained for the PVDF/MA/EG composites compared to the PVDF/EG composites that are lacking MA. For instance, The PVDF/MA/EG composite prepared with a mass ratio of 93:14:7 exhibits a high thermal conductivity of up to 0.73 W/mK. It is 32.7% higher than the thermal conductivity of the PVDF/EG composite that is prepared with a mass ratio of 93:7. Moreover, the introduction of MA leads to an increased melting peak temperature and crystallinity due to an increased nucleation site provided by the uniformly dispersed EG in the PVDF matrix. This study provides an efficient preparation method for PVDF/EG composites with a high thermal conductivity. [ABSTRACT FROM AUTHOR]

Ultrafine Polyvinyl alcohol (PVA) fibers have an outstanding potential in various applications, especially in absorbing fields. In this manuscript, an electrostatic-field-assisted centrifugal spinning system was designed to improve the production efficiency of ultrafine PVA fibers from PVA aqueous solution for NH3 adsorption. It was established that the fiber production efficiency using this self-designed system could be about 1000 times higher over traditional electrospinning system. The produced PVA fibers establish high morphology homogeneity. The impact of processing variables of the constructed spinning system including rotation speed, needle size, liquid feeding rate, and voltage on fiber morphology and diameter was systematically investigated by SEM studies. To acquire homogeneous ultrafine PVA fiber membranes, the orthogonal experiment was also conducted to optimize the spinning process parameters. The impact weight of different studied parameters on the spinning performance was thus provided. The experimental results showed that the morphology of micro/nano-fibers can be well controlled by adjusting the spinning process parameters. Ultrafine PVA fibers with the diameter of 2.55 μm were successfully obtained applying the parameters, including rotation speed (6500 rpm), needle size (0.51 mm), feeding rate (3000 mL h−1), and voltage (20 kV). Furthermore, the obtained ultrafine PVA fiber mat was demonstrated to be capable of selectively adsorbing NH3 gas relative to CO2, thus making it promising for NH3 storage and other environmental purification applications. [ABSTRACT FROM AUTHOR]

Nanostructured components have been receiving considerable attention in recent years. One advantage is the use of near-field electrospinning (NFES) in microdevice manufacture. Multi-nozzle NFES is offered as a technique to increase the high-precision production rate of components. The deposition characteristics of the multi-nozzles were observed and analyzed based on the mutual influence of the jets under varied conditions. It was discovered that the mutual distance of deposition becomes larger with increases in working distance and nozzle spacing, but the influence of voltage is not particularly apparent. This paper discusses the results and conclusions of the experimental investigation and theoretical derivation.

Catalysts with high carrier mobility, high activity, and an active basal plane have been highly sought for the hydrogen evolution reaction (HER). However, combining these advantages into one single material is a grand challenge. Herein, using first principles computations, we predicted that a two-dimensional (2D) Dirac nodal loop semimetal, namely the RuB4 monolayer, is promising as a superior catalyst for the HER. Our systematic computations showed that the single layer RuB4 is thermodynamically, dynamically, mechanically, and thermally stable and presents multiple Ru and B sites for the HER on the basal plane. The estimated Gibbs free energy for hydrogen adsorption at a Ru site is approaching zero (−8.8 meV), suggesting its excellent HER performance. The RuB4 monolayer is a Dirac nodal loop semimetal with high Fermi velocities, which can accelerate charge transfer between catalysts and reaction intermediates. The RuB4 monolayer is an auxetic material with an out-of-plane negative Poisson's ratio, implying its novel mechanical properties. This work provides an example of using a Dirac nodal loop semimetal for high-performance HER catalysts, which is a promising alternative to the known catalysts with trivial metallic properties. [ABSTRACT FROM AUTHOR]

Three-dimensional multimodality multi-object tracking has attracted great attention due to the use of complementary information. However, such a framework generally adopts a one-stage association approach, which fails to perform precise matching between detections and tracklets, and, thus, cannot robustly track objects in complex scenes. To address this matching problem caused by one-stage association, we propose a novel multi-stage association method, which consists of a hierarchical matching module and a customized track management module. Specifically, the hierarchical matching module defines the reliability of the objects by associating multimodal detections, and matches detections with trajectories based on the reliability in turn, which increases the utilization of true detections, and, thus, guides accurate association. Then, based on the reliability of the trajectories provided by the matching module, the customized track management module sets maximum missing frames with differences for tracks, which decreases the number of identity switches of the same object and, thus, further improves the association accuracy. By using the proposed multi-stage association method, we develop a tracker called MSA-MOT for the 3D multi-object tracking task, alleviating the inherent matching problem in one-stage association. Extensive experiments are conducted on the challenging KITTI benchmark, and the results show that our tracker outperforms the previous state-of-the-art methods in terms of both accuracy and speed. Moreover, the ablation and exploration analysis results demonstrate the effectiveness of the proposed multi-stage association method. [ABSTRACT FROM AUTHOR]

Multiple object tracking (MOT) in unmanned aerial vehicle (UAV) videos is a fundamental task and can be applied in many fields. MOT consists of two critical procedures, i.e., object detection and re-identification (ReID). One-shot MOT, which incorporates detection and ReID in a unified network, has gained attention due to its fast inference speed. It significantly reduces the computational overhead by making two subtasks share features. However, most existing one-shot trackers struggle to achieve robust tracking in UAV videos. We observe that the essential difference between detection and ReID leads to an optimization contradiction within one-shot networks. To alleviate this contradiction, we propose a novel feature decoupling network (FDN) to convert shared features into detection-specific and ReID-specific representations. The FDN searches for characteristics and commonalities between the two tasks to synergize detection and ReID. In addition, existing one-shot trackers struggle to locate small targets in UAV videos. Therefore, we design a pyramid transformer encoder (PTE) to enrich the semantic information of the resulting detection-specific representations. By learning scale-aware fine-grained features, the PTE empowers our tracker to locate targets in UAV videos accurately. Extensive experiments on VisDrone2021 and UAVDT benchmarks demonstrate that our tracker achieves state-of-the-art tracking performance. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition metal carbides (TMCs) have captured immense interest for their fascinating physical and chemical properties. Among them, bare carbide MXenes exhibit a metallic feature, greatly limiting the potential applications in optoelectronic devices. Herein, based on the particle swarm optimization and first-principles calculations, we predicted the existence of two single layer (SL) TMCs, namely, tetragonal β-MC and hexagonal γ-MC (M = Ti, Zr, Hf). The two structures are more stable than previously reported α-MC and possess semimetal and semiconductor properties, respectively. We further reveal that the β-MC monolayers have two nodal loops around the Fermi level. SL γ-TiC, ZrC, and HfC have a bandgap of 1.59, 1.24, and 1.57 eV, respectively, and display strong light-harvesting ability in the visible light range. Our research expands the 2D TMCs family beyond the extensively existing MXenes and greatly enriches the carbon chemistry. [ABSTRACT FROM AUTHOR]

We theoretically investigate physical properties of two-dimensional (2D) Fe2Ga2S5 by employing first-principles calculations. It is found that it is an antiferromagnet with zigzag magnetic configuration orienting in the in-plane direction, with Néel temperatures around 160 K. The band structure of the ground state shows that it is a semiconductor with the indirect band gap of about 0.9 eV, which could be effectively tuned by the lattice strain. We predict that the carrier transport is highly anisotropic, with the electron mobility up to the order of ∼103 cm2/(V⋅s) much higher than the hole. These fantastic electronic properties make 2D Fe2Ga2S5 a promising candidate for the future spintronics. [ABSTRACT FROM AUTHOR]

Electrospinning technology is considered to be one of the efficient, convenient, and low-cost technologies for preparing nanofibers, which can be applied in various industries, including filtration, catalysis, and energy. Here, aiming at the performance requirements of the nanometer fiber filter membrane for filtering PM2.5, the preparation of the nanofiber filter membrane was realized based on multi-needle electrospinning equipment. Meanwhile, by adding silver nitrate to the spinning solution, a polyvinylidene fluoride antibacterial nanofiber filter layer with high filtration efficiency and low resistance was successfully prepared on the traditional air conditioning filter meshes. We found that four key factors affecting the filtration performance include ambient humidity, substrate meshes, voltage, and production rate. Among them, voltage and production rate are the key factors affecting the filtration performance. According to the development trend of multifunctional nanofiber membranes, the preparation of air conditioning filters with nanofibers as the main filter material was realized, producing air conditioning filter membranes with antibacterial and deodorizing functions. This article provides a reliable experimental basis and empirical reference for the preparation of nanofiber membranes based on multi-needle electrospinning technology. [ABSTRACT FROM AUTHOR]

Dirac cone, one of the main characters of topological materials, provides us an approach to explore topological phase transitions and topological states. Single-element 2D-Xenes are prominent candidates for hosting Dirac cones. Till now, the multiple Dirac cones, Dirac-like cones, and semi-metal Dirac point have been discovered in them. However, it is still difficult to realize the tunable Dirac cones due to the lack of appropriate materials. Using first-principles calculations, this paper proposes that monolayer selenium with square lattice could achieve tunable Dirac cones and a topological phase transition. Double structural phases of the monolayer selenium can be distinguished according to strain applied, i.e., buckled square and buckled rectangular phases, which have rich Dirac physics. There exist four anisotropic Dirac cones in the buckled square phase, owing to fourfold symmetry. The buckled rectangular phase hosts a topological phase transition from a 2D topological insulator with double Dirac cones to a simple insulator, with a Dirac semi-metal having single Dirac point as the phase transition point. Moreover, the topological insulator has a global band gap of 0.16 eV, suggesting its potential utilizations in room-temperature devices. These studies will greatly promote the development of the Dirac physics and widen the application ranges of 2D-Xenes. [ABSTRACT FROM AUTHOR]

Within the framework of the graph model for conflict resolution, the concept of coalition improvement is generalized, resulting in new definitions of Nash, general metarational, symmetric metarational, and sequential stability applicable to coalitions. To illustrate how these generalized stability definitions can be applied to a real conflict, they are used to analyze an offshore oil exploration dispute that occurred in the South China Sea in 2014. The novel approach reveals which coalitions can upset a noncooperative equilibrium or support new cooperative equilibria, and which decision makers can benefit from joining a coalition. [ABSTRACT FROM AUTHOR]

An analytic model addressing the energy bandgap of nanoporous (NPs) structures with aligned cylindrical pores has been established from the perspective of nanothermodynamic considerations. It is found that the bandgap energies of NPs structures are unambiguously blueshifted as compared with those of nanowires with the same sizes and the bulk counterparts. The anomalous surface energies in the inner and outer surfaces of NPs structures seem the physical origin of the bandgap shifts. Agreement between the theoretical predictions and the evidence from experimental measurements and calculations suggested that the proposed method could be expected to be applicable to NPs structural materials. [ABSTRACT FROM AUTHOR]

In this study, an electroactive rotaxane, (S,S)-crown-3 , consisting of a polymeric chiral ionic liquid as a flexible axle and 18-crown-6 as the wheel, was designed and synthesized. It is worth noting that a stimuli-responsive system was developed, in which the wheel could switch its location between the chiral carbamido group and ionic pair of the ionic polymers under an external force. Next, (S,S)-crown-3 was employed as a modification on the surface of glassy electrode. In contrast to previous study, the developed probe presented a clear discrimination of an electrochemical signal in the absence of Cu(II). Under the external force (different pH values), L -isomers of amino acids (tryptophan, tyrosine, and cysteine) could form stable host–guest interactions with the chiral carbamido group, producing higher peak currents than the D -isomers. Compared to the absence of the crown, (S,S)-crown-3 showed much better recognition efficiency. The value of IL/ID for tryptophan could reach 39.8. In brief, the present study describes a powerful method for the synthesis of an electroactive rotaxane with great enantiorecognition capability. [ABSTRACT FROM AUTHOR]

Multi-needle electrospinning technology is a method for mass production of nanofibers, which can improve the production efficiency of nanofibers by increasing the number and density of needles for multi-needle electrospinning. However, when the arrangement density of the needle is high, the electric field of the needle tip is not uniform, causing instability such as jet dripping and broken jet. In this paper, the electric field uniformity optimization problem of multi-needle electrospinning technology is used to simulate the needle tip electric field by using COMSOL finite element analysis software. The influence of the needle size and the dielectric material on the electric field of the tip was studied. Finally, the method of using dielectric material on the tip of the middle part of the needle is beneficial to the electric field uniformity. The uniformity of the needle tip electric field in the case of high-density arrangement of the needle is realized, and the nozzle is provided for mass production of nanofibers by multi-needle electrospinning. [ABSTRACT FROM AUTHOR]

The near-field electrospinning is considered as one of the most effective techniques to direct-write aligned fibers which can be applied to various high-tech areas, including energy harvester, tissue engineering, and wearable sensors. For large area aligned pattern printing, the multi-nozzle electrohydrodynamic printing is an efficient method to enhance productivity. As a branch of electrohydrodynamic printing technology, the near-field electrospinning is a crucial concern to make an investigation for the formation of aligned nanofibers. Here we fabricated various nanostructures from beaded fibers to aligned fibers and crimped fibers by the double-nozzle near-field electrospinning process. We found three key parameters affecting the process, including the collector speed, the applied voltage, and the electrode-to-collector distance, and the collector speed is the key factor affecting the crimped frequency. This paper provides a reliable experimental basis and theoretical guidance for the multi-nozzle near-field electrospinning to accurately direct-write microfibers and nanofibers. [ABSTRACT FROM AUTHOR]

Angle-of-arrival (AoA) estimation is of great interest, particularly for using radio to localize a device; good estimates of angles result in good estimates of location. In this letter, we propose a signal processing and machine learning combined tool for the AoA estimation. In particular, we utilize regression models trained using the snapshot data collected using multiple antennas for estimating the angle of arrival. Based on a set of simulation and real measurements underthe Bluetooth 5 low-energy system in an indoor environment, the proposed method is able to provide a considerable and consistent improvement without significant additional computational effort. We show that the proposed approach for AoA estimation provides an improvement of at least 20% compared with the baseline approach of traditional Multiple Signal Classification algorithm. We evaluate the performance of the proposed methods and show a consistent improvement using a range of channel parameters, including elevation angles, SNRs, and channel configurations. [ABSTRACT FROM AUTHOR]

The electrospinning electric field is the main factor responsible for the jet stretching force. Previous studies showed that nonhomogeneous electric field would affect the jets formed during the multi-needles electrospinning. Therefore, a multitude of methods were explored to optimize the electric field in multi-needles electrospinning, such as adjusting the supplied voltage on each needle, varying the space of the needles and spatial distribution of the needles. In this paper, three categories of needles distribution were explored for a homogeneous electric field and the design of a higher needles density of electrospinning head. The theoretical and experimental results showed that the homogeneous electric field formed with the trapezoidal head at 15mm distance while the others’ head required over 30mm. Hence, the trapezoidal arrangement is a better multi-needles distribution for electrospinning head, and has much more significance for high yield of electrospinning nanofibers. [ABSTRACT FROM AUTHOR]