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Large-scale risk events in the venture capital (VC) market can easily lead to systemic risk in the financial market. This paper collects the comprehensive dataset of Chinese VC market from 1999 to 2020, and constructs the multi-layer networks of VC market. After that, a risk contagion model of venture capital market is designed considering both the capital loss transmission and social relations effect (investor herd behavior). By simulating various situations with different risk origins and scales, the speed of risk contagion and the total impacts on the overall stability of the market (network) are compared. We find that the herd behavior of the market will generally aggravate the consequences of risk contagion. Compared with unicorns, the failure of a leading VC firm can cause a wider range of risk contagion. The contagion consequences caused by the failure of random financing companies are more serious than those caused by random VC firms. Moreover, we identify that telecommunications services and information technology are high-risk industries in VC market. Based on the empirical results, this article provides policy implications for the market regulatory sectors to prevent VC market risks.

SiCw is expected to be candidate material for Accident Tolerant Fuel (ATF). Nevertheless, the distribution, morphology and size of SiCw have impacts on the thermal conductivity of composite fuels. An analysis model for UO2-SiCw was established using finite element method (FEM), and the effects of whisker orientation, size, volume fraction and aspect ratio on thermal conductivity were analyzed. The generation algorithm of SiCw was improved, and the results of thermal conductivity calculations showed that the improved model is closer to the experimental value. The effect of whisker orientation on thermal conductivity can be calculated by the cosine law of zenith angle and azimuth angle, and deriving a model for calculating thermal conductivity with specific whisker orientation. With the decrease of whisker size, the influence of Kapitza thermal resistance is significant. The formula used to calculate the whisker threshold diameter was deduced, and the results are in good agreement with the FEM results. With the increase of volume fraction of whiskers, the thermal conductivity increases linearly. For morphology, whiskers with high aspect ratio can achieve higher thermal conductivity. There is a value for the ratio of whisker length to matrix size, above which increasing whisker length will slow the increase in thermal conductivity (0.3 for whiskers along the direction of thermal conduction). The thermal conductivity of UO2-SiCw was optimized using the above conclusions, and the radial temperature distribution of pellet was analyzed. The results show that taking full advantage of the anisotropy of whisker heat transfer can significantly improve the thermal conductivity of composites and improve the operation condition of the pellet. The results can provide a good theoretical basis for designing whisker-doped composites with high thermal conductivity.

Venture capital market is one of the most important financial markets, which plays an important role in promoting industrial innovation and economic development. In this study, the complete data set of all venture capital events occurred in China from 2009 to 2020 was used to construct two kinds of complex networks, whose topological property and dynamic evolution trend of the network are studied. Specifically, we construct the co-investment network among investor, as well as the binary complex network of investor-entrepreneur, and propose the evaluation method of the importance and performance of venture capital institutions. Based on the proposed method, we identify some leading venture capital institutions with high performance and importance. Furthermore, this paper enlightens venture capital practitioners by discovering the investment behavior and preference of these leading institutions.

Let G be a graph. We say that a hypergraph H is a Berge-G if there is a bijection ϕ : E ( G ) → E ( H ) such that e ⊆ ϕ ( e ) for all e ∈ E ( G ) . For any r-uniform hypergraph H and a real number p ≥ 1 , the p-spectral radius λ ( p ) ( H ) of H is defined as λ ( p ) ( H ) : = max x ∈ R n , ‖ x ‖ p = 1 ⁡ r ∑ { i 1 , i 2 , … , i r } ∈ E ( H ) x i 1 x i 2 ⋯ x i r . In this paper, we study the p-spectral radius of Berge-G hypergraphs. We determine the 3-uniform hypergraphs with maximum p-spectral radius for p ≥ 1 among Berge-G hypergraphs when G is a path, a cycle or a star.

This erratum will correct the classification of Theorem 1 in Lin-Lu-Yau, Comm. Anal. Geom., 2014, that misses the Triplex graph., Comment: We updated the proof thanks to the referee's comments

Studying networked systems in a variety of domains, including biology, social science, and Internet of Things, has recently received a surge of attention. For a networked system, there are usually multiple types of interactions between its components, and such interaction-type information is crucial since it always associated with important features. However, some interaction types that actually exist in the network may not be observed in the metadata collected in practice. This article proposes an approach aiming to detect previously undiscovered interaction types (PUITs) in networked systems. The first step in our proposed PUIT detection approach is to answer the following fundamental question: is it possible to effectively detect PUITs without utilizing metadata other than the existing incomplete interaction-type information and the connection information of the system? Here, we first propose a temporal network model which can be used to mimic any real network and then discover that some special networks which fit the model shall a common topological property. Supported by this discovery, we finally develop a PUIT detection method for networks which fit the proposed model. Both analytical and numerical results show this detection method is more effective than the baseline method, demonstrating that effectively detecting PUITs in networks is achievable. More studies on PUIT detection are of significance and in great need since this approach should be as essential as the previously undiscovered node-type detection which has gained great success in the field of biology.