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Metro plays an important role in an urban public transport system. With the use of metro lines, the increasing flow of people has brought tremendous pressure to the operation of metro lines, resulting in different faults, thus affecting the travel of residents. How to qualitatively evaluate the robustness of the metro network after encountering faults is a problem worthy of attention. By 2018, ten metro lines have been opened in Nanjing, forming a radiation structure from the urban center to the surrounding suburbs. In this study, the metro faults in Nanjing in the past three years are counted and classified. The space L and space P models for the metro network are constructed. The robustness of a Nanjing metro network is measured by the three indicators: network connectivity efficiency, largest connected subgraph size, and average subgraph size. The concept of supernetwork is proposed, and the metro line is considered as a whole. The robustness changes of the Nanjing metro network caused by the attacks on the nodes and hyperedges of the metro network are analyzed. The results show that deliberate attack causes more damage than a random attack. When traffic hub stations and trunk lines are attacked, the performance of the metro network will decline sharply. The research conclusion has certain practical value to enhance the anti-fault ability of the metro network.

The development of the Internet finance makes the financial network become increasingly complex. Considering of the characteristics of Internet finance and relationship level, a framework including multitiered Internet financial network with investors, Internet financial intermediaries, traditional financial intermediaries and investees was proposed. Increasing relationship levels in our framework are assumed to reduce transaction costs as well as risk and to have some additional value for the decision-makers. From the perspective of cash flow, the competitive and cooperative relationships between various decision-makers were explicated, as well as their behavior and optimality conditions. We found that the decision-makers compete within a tier and cooperate between ties to optimize the whole Internet financial supernetwork. Under the Internet environment, the various decision makers face greater credit risk and operational risk, credit risk and operational risk brought about by the problem is more outstanding. The relationship level has little effect on investors' decision, but it mainly influences the behavior of Internet financial intermediaries and the traditional financial intermediaries.

Abstract Petroleum, the most important energy source in the world, plays an essential role in securing economic development. If a petroleum shortage happens, it will severely disrupt production and life. Cross-regional emergency scheduling can effectively alleviate a petroleum shortage and further enhance the efficiency of the emergency response. Considering the general lack of focus on cross-regional petroleum dispatching management, we propose a three-layer emergency scheduling network for petroleum based on a supernetwork model that can increase the regional emergency correlation by adding a transfer management process. Then, we compare the total demand for petroleum and the emergency costs considered in the petroleum emergency scheduling supernetwork model (the single-region and the cross-region scenarios). The result shows that the cross-regional emergency scheduling pattern can effectively enhance the efficiency of the emergency preparations and reduce the emergency costs in most cases. However, when the vulnerabilities in the cross-regional link grow or the regional linkage decreases, the effect of single-regional scheduling is better. In addition, the advantages of the cross-regional emergency scheduling network will be strengthened with an increase in its maximum emergency capability. Nonetheless, this advantage will disappear when the petroleum demand in the crisis layer reaches the maximum emergency response capacity. Finally, according to the comparative analysis simulation among scenarios, certain strategic policy recommendations are suggested to improve the petroleum emergency scheduling ability in regions. These recommendations include strengthening the cross-regional coordination mechanism, increasing the modes of petroleum transportation and enhancing the carrying capacity of regional emergency routes.

Compared with traditional course materials used in the classroom, the massive open online course (MOOC) forum that delivers unlimited learning content to students has various advantages. Yet MOOC has also received criticism recently, notably the problem of extremely low participation rates in its discussion forums. This study aims to explore the correlation between forum activity and student course grade in MOOC, and identify more accurately the forum activity levels of participants and the quality of threads in MOOC.

Supernetworks have long been adopted to address multi-dimensional choice problems, which are thorny to solve for classic singular networks. Originated from combining transport mode and route choice into a multi-modal network, supernetworks have been extended into multi-state networks to include activity-travel scheduling, centered around activity-based models of travel demand. A key feature of the network extensions is that multiple choice facets pertaining to conducting a full activity program can be modeled in a consistent and integrative fashion. Thus, interdependencies and constraints between related choice facets can be readily captured. Given this advantage of integrity, the modeling of supernetwork has become an emerging topic in transportation research. This paper summarizes the recent progress in modeling multi-state supernetworks and discusses future prospects.

According to the structural and functional characteristics of military communication network（MCN）,through constructing the military communication supernetwork（MCSN） description model,the concept of adjacent matrix of su-pernetwork,correlation matrix of classified nodes,type assortativity coefficient,and the definitions of supernetwork mo-tif,core and the entropy of the motif were introduced.Then regarding motifs as basic construct modules of MCSN,the supernetwork motif entropy（SNME） was proposed as a complexity measure of MCN.Finally,by taking the complexity measuring steps of a naval vessels fleet communication supernetwork structure which was discussed in detail as an ex-ample,the computing results of SNME were compared with the present complexity measures,and it was demonstrated that SNME could measure the functional complexity of network when its structural complexity was determined.

According to the structural and functional characteristics of military communication network（MCN）,through constructing the military communication supernetwork（MCSN） description model,the concept of adjacent matrix of su-pernetwork,correlation matrix of classified nodes,type assortativity coefficient,and the definitions of supernetwork mo-tif,core and the entropy of the motif were introduced.Then regarding motifs as basic construct modules of MCSN,the supernetwork motif entropy（SNME） was proposed as a complexity measure of MCN.Finally,by taking the complexity measuring steps of a naval vessels fleet communication supernetwork structure which was discussed in detail as an ex-ample,the computing results of SNME were compared with the present complexity measures,and it was demonstrated that SNME could measure the functional complexity of network when its structural complexity was determined.

The use of molecular markers with inadequate variation levels has resulted in poorly resolved phylogenetic relationships within Ilex. Focusing on southern South American and Asian species, we aimed at contributing informative plastid markers. Also, we intended to gain insights into the nature of morphological and physiological characters used to identify species. We obtained the chloroplast genomes of I. paraguariensis and I. dumosa, and combined these with all the congeneric plastomes currently available to accomplish interspecific comparisons and multilocus analyses. We selected seven introns and nine IGSs as variable non-coding markers that were used in phylogenomic analyses. Eight extra IGSs were proposed as candidate markers. Southern South American species formed one lineage, except for I. paraguariensis, I. dumosa and I. argentina, which occupied intermediate positions among sampled taxa; Euroasiatic species formed two lineages. Some concordant relationships were retrieved from nuclear sequence data. We also conducted integral analyses, involving a supernetwork of molecular data, and a simultaneous analysis of quantitative and qualitative morphological and phytochemical characters, together with molecular data. The total evidence tree was used to study the evolution of non-molecular data, evidencing fifteen non-ambiguous synapomorphic character states and consolidating the relationships among southern South American species. More South American representatives should be incorporated to elucidate their origin.