Asymmetric Influence Detection and Forecasting of Global Stock Markets Based on the Copula Theory

Correlation analysis of financial markets is an important starting point for modern financial theory of financial market risks. Along with the deepening of financial globalization, global financial markets have become more and more interdependent. Correlation analysis of global financial markets has become a hot issue for many scholars. On the basis of an in-depth study of Copula theory, this paper applies the theory to the asymmetric correlation analysis of the global major stock market indexes. First, asymmetric correlations among the selected stock indexes are modeled and detected using the relevant metrics of the Copula function on the logarithmic yield of stock indexes; The detected asymmetric correlations are put together to form a directed acyclic graph. Then, artificial neural networks (ANN) are used as a nonlinear model to predict the nearest future of the target stock index; the prediction accuracy is measured in terms of hit rate and mean square error. Test is done on historical daily data with the results showing that the Copula correlation coefficients are more informative for finding the influential leading markets for the predefined target market better than the traditional linear correlation coefficients. The hit rate of the ANN prediction using the detected leading markets found by Copula correlation coefficients is about 3% to 10% higher than that by the linear correlation coefficients

Epitaxial Growth of Germanium on Silicon for Light Emitters

National Basic Research Program of China [2007CB613404, 2012CB933503]; National Natural Science Foundation of China [61036003, 60837001, 61176092]; Fundamental Research Funds for the Central Universities [2010121056]This paper describes the role of Ge as an enabler for light emitters on a Si platform. In spite of the large lattice mismatch of similar to 4.2% between Ge and Si, high-quality Ge layers can be epitaxially grown on Si by ultrahigh-vacuum chemical vapor deposition. Applications of the Ge layers to near-infrared light emitters with various structures are reviewed, including the tensile-strained Ge epilayer, the Ge epilayer with a delta-doping SiGe layer, and the Ge/SiGe multiple quantum wells on Si. The fundamentals of photoluminescence physics in the different Ge structures are discussed briefly

Graphic loans: East Asia and beyond

The national languages of East Asia (Chinese, Japanese, Korean and Vietnamese) have made extensive use of a type of linguistic borrowing sometimes referred to as a 'graphic loan'. Such loans have no place in the conventional classification of loans based on Haugen (1950) or Weinreich (1953), and research on loan word theory and phonology generally overlooks them. The classic East Asian phenomenon is discussed and a framework is proposed to describe its mechanism. It is argued that graphic loans are more than just 'spelling pronunciations', because they are a systematic and widespread process, independent of but not inferior to phonological borrowing. The framework is then expanded to cover a range of other cases of borrowing between languages to show that graphic loans are not a uniquely East Asian phenomenon, and therefore need to be considered as a major category of loan

Mapping and Assessing the Supply and Demand of Rural Recreation Services in National Parks: A Case Study of Qianjiangyuan, Zhejiang, China

National parks not only protect natural resources but also provide a variety of cultural ecosystem services, with their rural areas serving as important locations for providing rural recreation services (RRS). Spatial quantification of RRS supply and demand will contribute to ensuring the protection and promotion of human well-being in national parks. In this study, we proposed an integrated framework to map and assess the spatial distribution of RRS supply and demand in Changhong Township, located within Qianjiangyuan National Park. We used a combination of spatial analysis and the MaxEnt model as tools, which played a positive role in saving time when modeling areas providing cultural ecosystem services. Based on the findings, the study area was divided into different zones to propose spatial planning measures. The results showed that (1) the MaxEnt model was robust in mapping RRS supply. RRS supply and demand distribution had high spatial heterogeneity. (2) The proportion of areas where RRS supply exceeded demand was 72.58%, primarily distributed in areas with a high level of naturalness at the periphery of the study area. (3) This study divided Changhong Township into four types of zones: developed recreation service area, potential recreation service area, recreation service demand area, and marginal recreation service area. We proposed suggestions for the scientific utilization and management of RRS in each zone. Overall, our findings provide a scientific basis for planning rural recreation spaces within national parks, promoting the comprehensive utilization of rural cultural ecosystem services

COMMUNITY PERCEPTION OF MANAGEMENT GOALS IN MATOUSHAN NATIONAL NATURE RESERVE

National nature reserve (NNR) is the important ecological baseline of the ecosystem security of the country. However, it is under the pressure of mass tourism, low participation of local community, and improper management. It is a matter of great urgency to determine strategies and tools in support of the balance between conservation and development of NNR. At present, the management system of NNR in China is a system where the country supervises and the local government manages. The perception of the NNR’s management aim has direct influence on the management efficiency and protection effect. In this paper, the issue with Matoushan National Nature Reserve in Jiangxi Province has been analyzed as an example. Local residents and administrators’ attitudes and perceptions of the management goals of the NNR were measured from three aspects: (1) response to current policies practiced in the reserve; (2) degrees of perception of community co-management; (3) expectation for future development of the reserve. Based on the measurement of community attitude and intention toward four dimensions of ecotourism and assessment of the values and current threats to Matoushan NNR, five sustainable development strategies have been put forward which involve ecological conservation and recovery, local culture revitalization, industry and program planning, educational tourism planning, and periphery development and management. Seeing the resources inside the reserve areas as a natural, cultural, social and economic asset, ecotourism planning is holistic by integrating the goals of natural resources conservation and those of social and economic improvement in revitalizing and managing NNR.</jats:p

The Influence of Sand Pore Structure on Air Migration During Air-Injected Desaturation Process

The air injection method serves as a liquefaction mitigation technique to improve the liquefaction resistance of the foundations by decreasing the degree of saturation. To investigate the desaturation effect of this technique in various soil strata of the foundation, thin plate model tests were conducted, considering the impacts of gradation and relative density, to visualize the air migration process and distribution. The findings reveal the following: (1) The air migration process, delineated by air injection parameters, comprises four distinct phases, with stages II and III notably influenced by the pore structure; (2) air migration is governed by the pore throat dimensions, particle arrangement, and connectivity within the pore structure, exhibiting two predominant patterns: channel flow, primarily driven by inertial forces, and chamber flow, predominantly influenced by viscous and capillary forces; (3) referring to the air injection port, the gas phase distribution within the sand samples is consistent in the horizontal direction but not in the vertical direction. The concentration area and uniformity of the gas phase distribution are controlled by the pore structure. These results suggest potential enhancements in the positioning of air injection ports within complex soil layers, as well as improvements in the construction process, both aimed at optimizing the desaturation effect

COMMUNITY PERCEPTION OF MANAGEMENT GOALS IN MATOUSHAN NATIONAL NATURE RESERVE

National nature reserve (NNR) is the important ecological baseline of the ecosystem security of the country. However, it is under the pressure of mass tourism, low participation of local community, and improper management. It is a matter of great urgency to determine strategies and tools in support of the balance between conservation and development of NNR. At present, the management system of NNR in China is a system where the country supervises and the local government manages. The perception of the NNR’s management aim has direct influence on the management efficiency and protection effect. In this paper, the issue with Matoushan National Nature Reserve in Jiangxi Province has been analyzed as an example. Local residents and administrators’ attitudes and perceptions of the management goals of the NNR were measured from three aspects: (1) response to current policies practiced in the reserve; (2) degrees of perception of community co-management; (3) expectation for future development of the reserve. Based on the measurement of community attitude and intention toward four dimensions of ecotourism and assessment of the values and current threats to Matoushan NNR, five sustainable development strategies have been put forward which involve ecological conservation and recovery, local culture revitalization, industry and program planning, educational tourism planning, and periphery development and management. Seeing the resources inside the reserve areas as a natural, cultural, social and economic asset, ecotourism planning is holistic by integrating the goals of natural resources conservation and those of social and economic improvement in revitalizing and managing NNR.</jats:p