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971.
在项目反应理论(IRT)框架下,采用计算机化自适应测验技术实现对情绪智力的智能测评.基于IRT系列分析(含单维性检验、模型拟合检验、局部独立性检验以及项目质量分析),构建了符合IRT测量学要求的情绪智力测评的题库,并以此为基础探讨了计算机化自适应测验技术在情绪智力智能测评(CAT-EI)中的应用.实验结果表明:(i)CAT-EI相关算法具有较高的参数估计精度,同时具有较理想的测量信度和效度;(ii)CAT-EI可使用较少的题量(Mean=9.88题)达到使用整个题库(67题)的测量精度,它一方面能做到减轻被试的测试负担,另一方面实现了对情绪智力高效、快速、准确的智能测评.总之,该研究为实现对情绪智力智能测评提供了一种新的测量技术支持. 相似文献
972.
Carotenoids are an essential component of cashew and can be used in pharmaceuticals, cosmetics, natural pigment, food additives, among other applications. The present work focuses on optimizing and comparing conventional and ultrasound-assisted extraction methods. Every optimization step took place with a 1:1 (w:w) mixture of yellow and red cashew apples lyophilized and ground in a cryogenic mill. A Simplex-centroid design was applied for both methods, and the solvents acetone, methanol, ethanol, and petroleum ether were evaluated. After choosing the extractor solvent, a central composite design was applied to optimize the sample mass (59–201 mg) and extraction time (6–34 min). The optimum conditions for the extractor solvent were 38% acetone, 30% ethanol, and 32% petroleum ether for CE and a mixture of 44% acetone and 56% methanol for UAE. The best experimental conditions for UAE were a sonication time of 19 min and a sample mass of 153 mg, while the CE was 23 min and 136 mg. Comparing red and yellow cashews, red cashews showed a higher carotenoid content in both methodologies. The UAE methodology was ca. 21% faster, presented a more straightforward composition of extracting solution, showed an average yield of superior carotenoid content in all samples compared to CE. Therefore, UAE has demonstrated a simple, efficient, fast, low-cost adjustment methodology and a reliable alternative for other applications involving these bioactive compounds in the studied or similar matrix. 相似文献
973.
分别采用频响函数法和复频率响应法对同一个数值算例进行了稳态响应、使用条件和范围以及误差来源分析,阐述了两种算法在工程执行过程中的特点及效率。 相似文献
974.
975.
Lead sulphide (PbS) nano-sculptured thin films (nSTFs) are prepared for the first time using glancing angle deposition technique by physical vapour deposition process. An anisotropic morphology is obtained, which provides an orientational effect. Due to this anisotropic nature of PbS nSTF an attempt has been made to check its effect on the alignment of nematic liquid crystals (LCs). Two different LC devices were fabricated, that is, anti-parallel aligned or electrically-controlled birefringence and hybrid twisted nematic. It is noticed that in both types of devices, good alignment is obtained with high extinction and contrast. A significant effect of these alignments on the electro-optic properties of the LC is reported such as the threshold voltage, response time and contrast ratio. 相似文献
976.
977.
Anand Mohan Yadav Nikkam Suresh Abhishek Sundaram Pravesh Painkra Ashish Kumar Raja Md Arshad 《Journal of Dispersion Science and Technology》2018,39(5):754-764
The high cost of the bridging liquid subdues the implementation and commercialization of oil agglomeration process. To overcome this problem, waste oils from different sectors were used in this present study. The performance of the process was assessed based on the responses like ash rejection and organic matter recovery. The aim of the present study was to investigate the usage of waste oils from different sectors and to optimize and analyze the behavioral pattern showcased by different variables (pulp density, oil dosage, agglomeration time and oil type) using response surface methodology (Box-Behnken design). Experimental investigation shows that the optimum pulp density, oil dosage, agglomeration time and oil type condition obtained as 3%, 15%, 15?min and waste engine oil, respectively. At optimum condition, the % ash rejection and % organic matter recovery obtained as 63.94% and 81.8%, respectively. 相似文献
978.
979.
TiO2 photocatalysis has been studied widely in environment protection and energy generation applications. But, the intrinsic absence of visible light response and the high recombination rate of photo-generated charge carriers significantly limited the efficiency of photocatalysis with TiO2 materials. Herein, a facile approach was constructed to develop visible-light-induced TiO2 photocatalysis by co-modification with Eu and Au nanoparticles. The synthesized Au/Eu-TiO2 material was characterized by XRD, SEM, TEM, DRS, XPS, and N2 adsorption measurements. Visible light catalytic performance of the Au/Eu-TiO2 catalyst was evaluated by using the photodegradation of RhB as a model reaction. It was shown that this Au/Eu-TiO2 exhibited a better photocatalytic activity than the single Au modified TiO2 (Au/TiO2) or the single Eu modified TiO2 catalyst (Eu/TiO2), and also exhibited a good reusability for the targeted reaction. This remarkably improved performance of Au/Eu-TiO2 could be attributed to the synergetic effect of Eu and Au co-decoration, which not only enhanced visible light absorption but also promoted charge carriers transfers as evidenced by DRS, XPS and transient photocurrent spectra. Moreover, a possible reaction mechanism for the Au/Eu-TiO2 photocatalysis was proposed. 相似文献
980.
Recent theoretical developments regarding the understanding of weakly chaotic transients in ferroelectric liquid crystals (FLCs), induced by electric field, are studied in terms of the interaction with magnetic field. Our research is related with the nonlinear dynamical system represented by a thin film of surface-stabilized FLC in smectic C* phase, and subjected by the swinging magnetic field. The computation of the Lyapunov exponents from the dynamic equation for the director field reveals that the director dynamics exhibits limit cycle, hyperchaotic attractor and strange attractor behavior in the dissipative nonlinear media. The transients between director’s phase space trajectories can be handled by the magnetic field parameters. The fundamental understanding of the director dynamics may have a valuable contribution to the applications of thin liquid crystal films. 相似文献