Opportunities and Challenges Faced by the Trade Cooperation of China and Africa

This paper is based on the new normal background that the early days macroeconomic stimulation lead to the waste of manufacturability and hasted to find a new trade market, So we use the RCA Index proposed by Balassa in 1965 to compute the RCA Index and RMA Index of the mainly ten products of the export and import trade between China and Africa, Then specifies the competitive industries and the disadvantage industries in two countries, furthermore affirms the high growth potential trading products among the China and Africa. At the end of the paper, several opportunities and challenges are proposed according to the empirical results

Measurement of Investment activity in China based on Natural language processing technology

The purpose of this study is to propose a new index to measure and reflect China's investment activity in time, and to analyze the changes of China's investment activity in the past five years. This study first uses the NEZHA model for semantic representation, and expand the indicator system based on semantic similarity. Then we calculate China's investment activity index by using the network search data. This study shows that China's investment activity began to decline in 2019, rebounded for a period of time after the outbreak of COVID-19 in 2020, and then continued to maintain a downward trend. Private investment activity has declined significantly, while government investment activity has increased. Among the provinces in Chinese Mainland, the investment activity of economically developed provinces has decreased significantly, while the investment activity of some economically less developed provinces in the north and south is higher. After the outbreak of COVID-19, the investment period became shorter. Our research will provide timely investment information for the government, decision makers and managers, as well as provide other researchers who also pay attention to investment with a perspective other than investment in fixed asset

Correlation, Breit and Quantum Electrodynamics effects on energy level and transition properties of W54+^{54+} ion

The electron correlation effects and Breit interaction as well as Quantum Electro-Dynamics (QED) effects were expected to have important contribution to the energy level and transition properties of heavy highly charged ions. The ground states [Ne]$3s^{2}3p^{6}3d^{2}$ and first excited states [Ne]3s$^{2}3p^{5}3d^{3}$ of W$^{54+}$ ion have been studied by using Multi-Configuration Dirac-Fock method with the implementation of Grasp2K package. A restricted active space was employed to investigate the correlation contribution from different models. The Breit interaction and QED effects were taken into account in the relativistic configuration interaction calculation with the converged wavefunction. It is found that the correlation contribution from 3s and 3p orbital have important contribution to the energy level, transition wavelength and probability of the ground and the first excited state of W$^{54+}$ ion

Selecting Genes by Test Statistics

Gene selection is an important issue in analyzing multiclass microarray data. Among many proposed selection methods, the traditional ANOVA F test statistic has been employed to identify informative genes for both class prediction (classification) and discovery problems. However, the F test statistic assumes an equal variance. This assumption may not be realistic for gene expression data. This paper explores other alternative test statistics which can handle heterogeneity of the variances. We study five such test statistics, which include Brown-Forsythe test statistic and Welch test statistic. Their performance is evaluated and compared with that of F statistic over different classification methods applied to publicly available microarray datasets

Markov Switching Model With Bounce-Back Effect: An Application to Chinese Business Cycle

Based on Markov switching model with a bounce-back effect, this paper analyzes the data of the economic growth in China. The findings suggest that Markov switching model with a rebound effect fits the macroeconomic growth data in our country better. What’s more, we can also see that the economic fluctuation in our country not only is characterized by its obvious nonlinearity and asymmetry but has significant “bounce-back effect”