Kappa Analysis of Industrial Park Risk Evaluation Index System

AbstractIn the industrial park regional risk evaluation process, expert evaluation method is usually used to budget the constructed index system, so that the overall park risk value can be quantified. During setting the estimation system and expert assignment, in order to comply with the objective factor, Kappa statistics analysis method is adopted to evaluate the consistency analysis of the system setting of regional risk estimation and the expert's assignment situation. The Kappa statistic is an statistical index which via comparing two or more observers on the same things, or the twice or more observation results of one observer on the same thing,and the difference between the consistency and the consistency of actual observed value,which is caused by opportunity or by actual measurement, is used as statistical index. Kappa statistic and weighted Kappa statistic not only can be used to inspect the consistency and the reproducibility of ordered and unordered variable data, but also can give a magnitude which reflects the consistency. During the course of assessment, experts coming from different departments give respective grades of safety conditions in industrial park. Then indexes setup and grades by experts are discussed. The results indicate that grades by experts show good consistency

Solvothermal Preparation of CaTiO3 Prism and CaTi2O4(OH)2 Nanosheet by a Facile Surfactant-Free Method

Calcium titanate (CaTiO3) with prism-like-shaped and CaTi2O4(OH)2 nanosheet-like morphology were synthesized by a simple solvothermal route without any surfactants. X–ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR) were employed to investigate the microstructure of the samples. The experimental results showed that NaOH concentration played a key role for the formation of CaTiO3 prisms. With increasing NaOH concentrations, the obtained sample changed from CaTi2O5 aggregated particles to CaTi2O4(OH)2 nanosheets, and then to CaTiO3 prisms. When NaOH concentration was 7 M, CaTiO3 morphology is mainly composed of regular prisms. A rational mechanism was proposed to illustrate the morphology evolution of the samples synthesized at various NaOH concentrations. And the CaTi2O4(OH)2 interlaminar structure was illustrated.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9697</p

An Unsafe Behavior Detection Method Based on Improved YOLO Framework

In industrial production, accidents caused by the unsafe behavior of operators often bring serious economic losses. Therefore, how to use artificial intelligence technology to monitor the unsafe behavior of operators in a production area in real time has become a research topic of great concern. Based on the YOLOv5 framework, this paper proposes an improved YOLO network to detect unsafe behaviors such as not wearing safety helmets and smoking in industrial places. First, the proposed network uses a novel adaptive self-attention embedding (ASAE) model to improve the backbone network and reduce the loss of context information in the high-level feature map by reducing the number of feature channels. Second, a new weighted feature pyramid network (WFPN) module is used to replace the original enhanced feature-extraction network PANet to alleviate the loss of feature information caused by too many network layers. Finally, the experimental results on the self-constructed behavior dataset show that the proposed framework has higher detection accuracy than traditional methods. The average detection accuracy of smoking increased by 3.3%, and the average detection accuracy of not wearing a helmet increased by 3.1%

Antibacterial Activity of Oxygen Vacancy-Mediated ROS Production of V₆O₁₃ Powder against <i>Candida albicans</i>

The emergence of drug resistance due to the overuse of antibiotics has made the prevention and treatment of invasive fungal infections caused by Candida albicans (C. albicans) a great challenge. Oxygen vacancy-rich inorganic materials show great promise in the antimicrobial field due to their unique physicochemical properties. Defect engineering can significantly optimize the electronic structure of inorganic materials to further enhance their antimicrobial activity. We designed oxygen vacancy defect-rich V6O13 powders using the hydrothermal-calcination method and investigated their anti-C. albicans activity. The results showed that the stronger antibacterial activity is attributed to the fact that the optimized V6O13 powder oxygen vacancy defects induced a reduction reaction of dissolved oxygen in the environment, which produced ROS with strong oxidative properties, causing damage to the wall membrane of C. albicans and leakage of intracellular material. The minimum inhibitory concentration (99% or more inhibition) of V6O13 powders is 4 mg/mL. This work not only provides a facile method for constructing oxygen-rich vacancies in V6O13 powders, but also provides new insights into the potential of inorganic materials optimized by defect engineering for efficient antimicrobial activity

Significantly Enhanced Self-Cleaning Capability in Anatase TiO₂ for the Bleaching of Organic Dyes and Glazes

In this study, the Mg2+-doped anatase TiO2 phase was synthesized via the solvothermal method by changing the ratio of deionized water and absolute ethanol Vwater/Vethanol). This enhances the bleaching efficiency under visible light. The crystal structure, morphology, and photocatalytic properties of Mg-doped TiO2 were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, N2 adsorption-desorption, UV-Vis spectroscopy analysis, etc. Results showed that the photocatalytic activity of the Mg2+-doped TiO2 sample was effectively improved, and the morphology, specific surface area, and porosity of TiO2 could be controlled by Vwater/Vethanol. Compared with the Mg-undoped TiO2 sample, Mg-doped TiO2 samples have higher photocatalytic properties due to pure anatase phase formation. The Mg-doped TiO2 sample was synthesized at Vwater/Vethanol of 12.5:2.5, which has the highest bleaching rate of 99.5% for the rhodamine B dye during 80 min under visible light. Adding Mg2+-doped TiO2 into the phase-separated glaze is an essential factor for enhancing the self-cleaning capability. The glaze samples fired at 1180 °C achieved a water contact angle of 5.623° at room temperature and had high stain resistance (the blot floats as a whole after meeting the water)

Preparation of Glass-Ceramics in the R₂O-Bi₂O₃-B₂O₃-SiO₂ System Applied in Automobile Glass Enamel

Environmental deterioration has put higher requirements on the acid resistance of automotive glass enamel. The present paper aims to prepare acid-resistant glass-ceramics used in automobile glass enamel. Base glasses with the compositions 15R2O-xBi2O3-10B2O3-(75-x) SiO2 (R2O is a mixture of Li2O, Na2O, and K2O (1:1:1, molar ratio), where x = 10, 15, 20, 25, and 30, respectively) was prepared by the melt-quenching method, and glass-ceramics were prepared by their controlling crystallization heat treatment. Crystallization behavior and crystallization ability of base glasses were investigated using the thermal stability parameter (S), the crystallization kinetics calculation results of base glasses, as well as the phase identification results of the heat-treated samples. The effects of the heat treatment temperature on the micromorphology and acid resistance of the heat-treated glasses were also investigated. Then, the optimized glass ceramic was used to prepare automotive glass enamel. The results indicate that: (I) with the increase of Bi2O3/SiO2 ratio, the characteristic temperature of the base glass decreases, the coefficient of thermal expansion (CTE) and crystallization ability increases significantly, the crystallization temperature range becomes wider; (II) the crystallization activation energy of base glasses are in the range of 169~264 kJ/mol; (III) Bi2SiO5 and Bi2O2SiO3 metastable phases are mainly precipitated when the crystallization temperature is between 530 °C and 650 °C, while only Bi4Si3O12 phase is precipitated when the crystallization temperature is above 650 °C; (IV) crystallinity of base glass increases significantly with increasing heat treatment temperature, which is beneficial to improve the acid resistance of heat treated products; (V) automotive glass enamel was prepared by mixing 15R2O-25Bi2O3-10B2O3-50SiO2 glass-ceramic powder with copper-chrome black and varnish, and then printed on the automobile glass substrate. All the properties of the sintered enamel can meet the market requirements, and the acid resistance of our product is better than that of market products