The air leakage in sintering machines affects the technological and economic indexes of the sintering process. It is of great significance to monitor and estimate the key areas. Mathematical models ...of sintering air leakage through holes in the steady-state process are given based on the fluid mechanics to predict the flow rate and effect on the key area. It was found that the hole model is the application of constant orifice outflow in the computation of sintering air leakage. The counter-flow bed model is suitable for predicting the flow rate through a complete break in sintering wind boxes. Furthermore, This paper proposes a new hole–bed generalized model to cover all the possible hole diameters for further high-precision application. The model connects the leakage hole diameter with the sintering process for the first time and establishes their coupling relationship. The pressure state in the sintering system depends on the ratio of the leakage hole area to the sintering bed area. The proposed fast estimation models are a step forward in developing more precise and powerful calculation tools to foresee the effects and consequences of sintering air leakage. It has a good prospect for reducing and replacing complex manual measurement and bringing some insight into the state of the art that could be improved in the future.
An estimation of the power battery state of charge (SOC) is related to the energy management, the battery cycle life and the use cost of electric vehicles. When a lithium-ion power battery is used in ...an electric vehicle, the SOC displays a very strong time-dependent nonlinearity under the influence of random factors, such as the working conditions and the environment. Hence, research on estimating the SOC of a power battery for an electric vehicle is of great theoretical significance and application value. In this paper, according to the dynamic response of the power battery terminal voltage during a discharging process, the second-order RC circuit is first used as the equivalent model of the power battery. Subsequently, on the basis of this model, the least squares method (LS) with a forgetting factor and the adaptive unscented Kalman filter (AUKF) algorithm are used jointly in the estimation of the power battery SOC. Simulation experiments show that the joint estimation algorithm proposed in this paper has higher precision and convergence of the initial value error than a single AUKF algorithm.
In this study, we investigated the wake-vortex dynamics behind a circular cylinder with an active symmetric jet control on its leeward surface by using high-speed particle image velocimetry (PIV) via ...wind tunnel tests. The experimental investigations were performed at a Reynolds number (Re) of 3.33 ×104. Steady slot jets were acted symmetrically into the near-wake region from the leeward surface of the cylindrical model. The azimuthal position of the slot jets was varied from 0°to 90°from the center-line. The proper orthogonal decomposition (POD) method was used as a tool to study the effect of modifications of active jets on the periodic vortex shedding and their dynamic interactions in the cylinder wake. Both dynamic evolutions and time-averaged results in the near-wake region were presented and analyzed to demonstrate the control effects of the symmetric jets. The experimental results indicated that the unsteady wakes of the cylinder were stabilized and attenuated when the azimuthal angle of the jets was set to 0°and 90°, whereas for other azimuthal angles, the symmetric jets were oblique to the sheared layers and their control effects were limited.
•The circular cylinder flow is controlled with symmetric active jets positioned at its leeward surface.•The azimuthal position of slot jets is found to play an important role in flow control effects.•Both parallel and vertical jets help to stabilize the dynamic wake and attenuate the unsteady vortex shedding from the cylinder.
Machine learning can handle an ever-increasing amount of data with the ability to learn models from the data. It has been widely used in a variety of disciplines and is gaining increasingly more ...attention nowadays. As it is challenging to map soil and hydrological information that are characterised with high spatial and temporal variability, applications of machine learning in soil science and hydrology (AMLSH) have become popularised. To better understand the current state of AMLSH research, a scientific and quantitative approach was performed to statistically analyse publication information from 1973 to 2021 archived in the Scopus database using scientometric analysis tools, including VOSviewer, CiteSpace, and the open-source R package "bibliometrix". The results show a significant increase in the number of publications on AMLSH since 2006. The major contributions were identified based on country origins (China, the USA, and India), institutions (Hohai University, Islamic Azad University, and Wuhan University), and journals (Journal of Hydrology, Remote Sensing, and Geoderma). The keywords analysis of the AMLSH research demonstrates four research hotspots: neural network, artificial intelligence, machine learning, and soil. The most frequently utilised machine learning (ML) methods are neural networks, decision trees, random forests and other methods for image processing and predictive analysis. McBratney et al. 2003 is the most highly cited article. Our research sheds light on the research process on AMLSH and concludes with future research perspectives.
A novel adaptive fuzzy control approach with low computational costs is addressed for the longitudinal non-affine model of a generic hypersonic vehicle subject to parametric uncertainties, capable of ...guaranteeing that altitude and velocity tracking errors exhibit prescribed performance. A new performance function is devised to impose preselected bounds on the transient and steady-state tracking error performance, and then a transformed error is constructed, which converts the original “constrained” system into an equivalent “unconstrained” one for the simplicity of control designs. Furthermore, a simplified fuzzy controller is exploited for the altitude subsystem, eliminating the issue of “explosion of complexity” that is associated with back-stepping control. For the velocity subsystem, a prescribed performance-based proportional–integral controller is utilized. The special contributions of the proposed control strategy are that it can guarantee altitude and velocity tracking errors with desired transient and steady-state performance, and meanwhile the computational load is quite low. Finally, numerical simulation results are presented to verify the efficiency of the design.
This article investigates the robust adaptive control system design for the longitudinal dynamics of a flexible air‐breathing hypersonic vehicle (FAHV) subject to parametric uncertainties and control ...input constraints. A combination of back‐stepping and nonlinear disturbance observer (NDO) is utilized for exploiting an adaptive output‐feedback controller to provide robust tracking of velocity and altitude reference trajectories in the presence of flexible effects and system uncertainties. The dynamic surface control is introduced to solve the problem of “explosion of terms.” A new NDO is developed to guarantee the proposed controller's disturbance attenuation ability and to performance robustness against uncertain aerodynamic coefficients. To deal with the problem of actuator saturation, a novel auxiliary system is exploited to compensate the desired control laws. The stability of the presented NDO and controller is analyzed. Simulation results are given to demonstrate the effectiveness of the presented control strategy.
With the ability to activate certain signaling pathways, chemokines and their receptors may facilitate tumor progression at key steps, including proliferation, immunomodulation, and metastasis. ...Nevertheless, their prognostic value and regulatory mechanism warrant thorough studies in liver cancer. Here, by screening the expression profiles of all known chemokines in independent liver cancer cohorts, we found that CCL23 was frequently downregulated at mRNA and protein levels in liver cancer. Decreased CCL23 correlated with shortened patient survival, enrichment of signatures related to cancer stem cell property, and metastatic potential. In addition to serving as a tumor suppressor through recruiting CD8+ T cell infiltration in liver cancer, CCL23 could repress cancer cell proliferation, stemness, and mobility. Mechanistically, the expression of CCL23 was transcriptionally regulated by ESR1. On the other hand, CCL23 could suppress the activation of AKT signaling and thus promote the expression of ESR1, forming a feedback loop in liver cancer cells. Collectively, these findings reveal that loss of CCL23 drives liver cancer progression by coordinating immune evasion and metastasis initiation. Targeting the ESR1/CCL23/CCR1/AKT regulatory axis could be an effective therapeutic strategy.
Downregulated expression of CCL23 is associated with poor prognosis in liver cancer. Loss of CCL23 drives liver cancer progression by coordinating immune evasion and metastasis initiation. Mechanistic study reveals an ESR1/CCL23/CCR1/AKT feedback loop.
Fluorescence-labeling technology has been widely used for rapid detection of pesticides in agricultural production. However, there are few studies on the use of this technology to investigate ...pesticide uptake and transport in plants with fluorescent nanoparticle formulations. Here, we investigated uptake, transport, accumulation and metabolism of imidacloprid loaded in fluorescent mesoporous SiO2 nanoparticles (Im@FL-MSNs) in tomato plants, and compared the results with the pesticide application in granular formulation. The results revealed that Im@FL-MSNs applied via root uptake and foliar spray both could effectively transport in tomato plants and carry the imidacloprid to plant tissues. Neither Im@FL-MSNs nor imidacloprid was detected inside of tomato fruits from root uptake or foliar spray applications. Compared with the foliar application of granular formulation, imidacloprid in Im@FL-MSNs demonstrated a higher concentration in leaves (1.14 ± 0.07 mg/kg > 1.08 ± 0.04 mg/kg, 1.13 ± 0.09 mg/kg > 1.11 ± 0.02 mg/kg), longer half-life (0.84 d < 1.31 d, 0.90 d < 1.36 d) and small numbers of metabolites formed. These results suggest that mesoporous silica nanoparticles could serve as an effective and efficient pesticide carrier for achieving the high use efficiency in plant protection. The information is also helpful to guide the pesticide applications and assess the risks associated with environmental quality and dietary consumption of vegetables.
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•Dynamic transport of Im@FL-MSNs in tomato was verified by fluorescence technology.•Morphological changes of silica nanoparticles in tomato were studied using TEM.•Metabolic mechanism of imidacloprid was verified by DFT and UPLC-MS/MS.•Im@FL-MSNs has a low risk of application on tomatoes.
Quality control of Chinese medicine (CM) is mainly based on chemical testing, which sometimes shows weak correlation to pharmacological effects. Thus, there is a great demand to establish ...bioactivity-based assays to ensure the quality of CM. The aim of the present study was to establish a bioassay-based approach to evaluate the biological activity of Xuesaitong injection (XST) based on an
zebrafish model. Zebrafish larvae with arachidonic acid (AA)-induced thrombus were applied to evaluate anti-thrombosis effects of XST and explore the potential mechanism of XST. Analysis of major components in normal and abnormal XST samples was performed by high performance liquid chromatography (HPLC). The results indicate that XST could significantly restore heart red blood cells (RBCs) intensity of thrombotic zebrafish in a dose-dependent manner, whilst decreasing RBCs accumulation in the caudal vein. The results were confirmed using a green fluorescence protein (GFP)-labeled zebrafish thrombosis model. Moreover, we could show that XST downregulates the expression of the
(
) gene to inhibit the coagulation cascade during the process of thrombosis in zebrafish. Notoginsenoside R
ginsenoside Rg
, ginsenoside Rb
and ginsenoside Rd, which were considered to be the major components of XST, also showed moderate anti-thrombosis efficacy. Further results showed that the zebrafish thrombosis model could efficiently distinguish five abnormal batches of XST from 24 normal batches. Furthermore, the inhibition rates of different batches were correlated with the content level of major components. Our results suggested that the proposed zebrafish thrombosis model could be successfully used to evaluate the batch-to-batch consistency of XST, which provided an alternative way for the quality control of CM.
Colorectal cancer (CRC) poses a heavy threat to human health owing to its high incidence and mortality. Circular RNAs (circRNAs) were investigated to participate in the progression of CRC, whereas ...there was no revenant data on the CRC process regulated by hsa_circ_0000231. This study aimed to explore the effects of hsa_circ_0000231 on CRC progression and underneath regulatory mechanism.
The expression levels of hsa_circ_0000231, miR-502-5p, and Myosin VI (MYO6) mRNA were detected by quantitative real time polymerase chain reaction (qRT-PCR). Western blot was employed to determine the protein expression levels of MYO6 and proliferating cell nuclear antigen (PCNA). The effects of hsa_circ_0000231 on cell proliferation, apoptosis, migration, and invasive in CRC were determined by cell counting kit-8 proliferation (CCK-8) and colony formation assays, flow cytometry analysis, wound-healing assay, and transwell invasion assay, respectively. Glucose uptake and lactate production were severally illustrated by glucose assay kit and lactate assay kit. The relationship between miR-502-5p and hsa_circ_0000231 or MYO6 was predicted by circular RNA interactome or targetScan online databases, and identified by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. In vivo tumor formation assay was carried out to determine the effects of hsa_circ_0000231 knockdown on tumor growth in vivo.
Hsa_circ_0000231 expression was dramatically upregulated while miR-502-5p was obviously downregulated in CRC tissues and cells compared with control groups. Hsa_circ_0000231 knockdown repressed the expression levels of MYO6 and PCNA protein. Functionally, hsa_circ_0000231 knockdown repressed cell glycolysis, proliferation, migration and invasion, and induced cell apoptosis, whereas these effects were decreased by miR-502-5p inhibitor. Mechanistically, hsa_circ_0000231 acted as a sponge of miR-502-5p and miR-502-5p bound to MYO6. Furthermore, hsa_circ_0000231 knockdown decreased tumor volume and weight of CRC in vivo.
Hsa_circ_0000231 knockdown inhibited CRC progression and glycolysis by downregulating MYO6 expression through sponging miR-502-5p, which might provide a theoretical basis in further studying circ_0000231-directed therapy in CRC.
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