初任消防救援人员的心理适应与影响因素

良好的心理适应能力是消防救援人员保持身心健康、应对各种作战情境、完成好救援任务的有力保障。初任消防救援人员指初任大学生干部和新消防员,他们从大学或社会来到消防救援队伍,所处的自然和社会环境、人际关系、学习方式以及生活方式等都发生了极大改变,面对救援现场和战训情境的冲击,容易出现心理、生理以及社会的不适感,即初任消防救援人员心理适应不良,程度严重的将会影响到初任消防救援人员的健康成长和发展进步。     

Comparative investigation of physical,X-ray and neutron radiation shielding properties for B2O3-MnO2-CdO borate glasses

B₂O₃-MnO₂-CdO ternary oxide glasses with amorphous properties were synthesised using the melt-quenching method. Structural and physical property analyses showed that the amount of non-bridging oxygen and the system stiffness increases, and the oxide network filling is more tightly packed as cadmium oxide (CdO) gradually replaces manganese Oxide (MnO₂) in the glass. The radiation-shielding performance of the B₂O₃-MnO₂-CdO glasses was evaluated using the shielding parameters calculated by the MCNPX simulation and the Phy-X program. Glasses with 40% and 50% CdO loading exhibited an average specific lead equivalent (PbE) of 0.241 and 0.294 mmPb/mm in the medical X-ray diagnostic area at 0.03–0.08 MeV; thus, they could fully meet the specific PbE requirements for application as "protection devices against diagnostic medical X-radiation". Furthermore, their photon attenuation capability is superior to that of various commercial shielding glasses in fast-neutron nuclear applications at 1°–10³ MeV. In addition, compared to the borate glass systems studied in the literature, B₂O₃-MnO₂-CdO glasses have fast neutron removal cross-sections of 0.125 cm⁻¹ at a smaller density of 3.9043–4.8135 g/cm³, making them potentially excellent fast neutron absorbers.     

基于多特征融合和微信小程序的用户窃电行为检测方法

常规的窃电行为检测方法是以窃电标签映射的方式进行检测,不具备窃电标签的窃电行为无法被有效检测,导致检测模型的交叉熵较大,影响了检测精准度。因此,文中设计了基于多特征融合和微信小程序的用户窃电行为检测方法。在微信小程序上设计了一个电量电费异常辅助判断的工具,提取出用户窃电行为特征。并利用多特征融合技术,构建出用户窃电行为检测模型,最大限度地提高了用户窃电行为检测精准度。采用对比实验的方式,验证了该检测方法的交叉熵更趋近于“0”,检测精准度更高,能够应用于实际生活。     

基于混合深度模型的虚假信息早期检测

针对一种信息特征进行检测方法在信息传播早期阶段提取的特征信息往往不充分,导致传播早期阶段检测准确率较低的问题,提出一个新颖的混合深度模型EGSI,模型由EXTRACT、GRU、SCORE和INTERATE 4个模块组成。EXTRACT通过卷积神经网络提取信息的传播路径特征,GRU通过门控循环单元捕获信息的文本特征和反馈特征,SCORE基于用户行为挖掘用户特征,INRERATE整合以上特征并预测出信息事件类标。EGSI通过整合信息最基本的4种特征(文本、用户、反馈、传播路径),从而可以在信息传播的早期阶段充分提取可用特征信息,进而较准确地检测出虚假信息。真实数据集的试验结果表明,模型在信息传播60 min内的准确率达到95.9%。相比基准方法,EGSI模型在检测虚假信息的准确率和时效性之间取得了较好的平衡。     

Zero-thermal-quenching of LiAl5O8: Eu2+, Mn2+ phosphors by energy transfer and defects engineering

The photoluminescence behavior of inorganic phosphors is generally influenced by thermal stability, which determines the luminescence efficiency of the corresponding devices. Here, a series of Eu²⁺, Mn²⁺ co-doped LiAl₅O₈ blue-green-emitting phosphors with thermal robust are successfully fabricated. The concentration-dependent emission spectra and the decay curves of the as-obtained LiAl₅O₈: Eu²⁺, Mn²⁺ samples manifest the occurrence of the energy transfer from Eu²⁺ to Mn²⁺ ions via dipole-dipole interaction, and the corresponding emitted colors are gradually modulated from blue to green under the excitation of 310 nm. Moreover, the zero-thermal-quenching luminescence is observed when the operation temperature is up to 423 K, which is attributed to the energy release from the trapping centers to emitting centers (Eu²⁺ and Mn²⁺) at high temperature. Furthermore, a warm white light-emitting diodes (WLEDs) device with correlated color temperature of 5061 K, a color rendering index of 80.6 and long-term stability is fabricated by combining UV LED chip (λ_ex = 310 nm), as-obtained LiAl₅O₈: Eu²⁺, Mn²⁺ phosphor, commercially available red phosphor and green phosphor. These results prove the potential application of the as-obtained LiAl₅O₈: Eu²⁺, Mn²⁺ phosphor for UV-pumped WLEDs devices.     

A relook at the mobile advertising landscape: What are the new consumer expectations in the retailing industry?

Following the rapid proliferation of mobile devices and the phenomenal advancements in mobile commerce, mobile advertising has since overtaken traditional advertising and seized the lead as the primary advertising channel for businesses. This research seeks to unveil the salient factors that affect the efficacy of mobile advertising in driving purchase intention by expanding the Web Advertising Model to include additional mobile advertising attributes (i.e., credibility and incentive) while considering the role of brand attitude in the process. A cross-sectional study was conducted with quantitative data obtained from 300 eligible respondents through an offline questionnaire survey. The empirical data were subsequently validated using the Structural Equation Modelling Artificial Neural Network (SEM-ANN) method to determine the non-compensatory non-linear relationships. All four ANN models show consistent results with the SEM analysis. The results indicate that consumer perceptions and expectations toward mobile advertising have shifted over time, such that the qualities of informativeness, irritation, and entertainment no longer play a critical role in determining mobile advertising value. On the other hand, the credibility and incentive of mobile advertising were found to be far more crucial in swaying such evaluations. Moreover, mobile advertising value was found to positively affect consumer attitudes towards the mobile advertisement and the advertised brand, which ultimately leads to purchase intention. This study offers an insightful overview of the modern mobile advertising environment that practitioners may use as a handy guide to optimise their mobile advertising strategies to suit the current perceptions and expectations of consumers.     

Significant improvement on quality factor in Bi3+/Ta5+ codoped Ce2Zr3-3xBi1.5xTa1.5xMo9O36 microwave dielectric ceramics with ultra-low sintering temperatures

Molybdenum oxide-based ceramics have attracted intense interest due to ultra-low sintering temperatures. However, low quality factors (Q × f) hinder their practical applications. Although Q × f can be improved by ions doping, the sintering temperature is greatly increased. Accordingly, it is still a challenge to obtain high Q × f ceramics sintered at ultra-low temperatures (<660 °C). Herein, (Bi_0.5Ta_0.5)⁴⁺ ions are utilized to tackle this issue in the Ce₂Zr₃(MoO₄)₉ ceramic as a prototype. Density and scanning electron microscope (SEM) results uncover good sintering states, and X-ray diffraction (XRD) results reveal the formation of solid solutions. Interestingly, the Ce-O bonds exhibit a dominant contribution to the bond ionicity (f_i), while Mo-O bonds play an important role in the lattice energy (U), the bond energy (E) and the thermal expansion coefficient (α). The remarkable increase of Q × f can be interpreted by the enhancement of the packing fraction and the mean U of Mo-O bonds. Moreover, the variations of the dielectric constant (ε_r) and the temperature coefficient of the resonance frequency (τ_f) can be explained by the variations of the intrinsic parameters. More interestingly, a negative correlation between Q × f and τ_f is first found. Typically, the CZ_0.98B_0.02 ceramic sintered at 650 °C exhibits optimum microwave dielectric properties: ε_r = 9.92, Q × f = 110,670 GHz, and τ_f = −19.20 ppm °C⁻¹. Notably, Q × f of the Ce₂Zr_2.94Bi_0.03Ta_0.03Mo₉O₃₆ (CZ_0.98B_0.02) ceramic is about 6 times larger than that of the matrix while retaining a low sintering temperature of 650 °C and a low ε_r of 9.92, making it a promising candidate for ultra-low temperature cofired ceramics (ULTCC) applications.