Search

This paper proposes a method for calculating transport networks capacity in dealing with multimodal transfers. Multimodal networks are represented by a modified 'supernetwork', while the passenger's travels are defined as 'superpaths'. Within this framework, the relation between the travel demand from O-D matrices and the resulting link flows in the supernetwork is modelled as a relationship matrix to describe urban mobility by using a logit-based stochastic user equilibrium. Based on this relationship matrix, an approximate iteration algorithm (AIA) is developed. Our numerical results show that the AIA performs better than the sensitivity analysis-based algorithm (SAB) and genetic algorithm (GA) regarding the execution-time, and that the capacity of multimodal transport networks can be underestimated if the combined travels are neglected. [ABSTRACT FROM AUTHOR]

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of the preferences of different user groups for various travel indices of public transit, this paper formulated a corresponding variational inequality model ( VIM) of transit assignment that combined multiple transit modes. Firstly, this paper made use of the conception of supernetwork to describe the transit behaviors in transfer zones, upload zones and download zones in a virtual network. Secondly,it presented a transit assignment VIM based on the user equilibrium principle. It proved mono- tone of the feature mapping of VIM to guarantee the feasibility of the following algorithm. To solve the above VIM, this paper proposed a modified projected gradient method based on gradually generating the effective paths and proved the effectiveness of the new algorithm theoretically. At last, the numerical experiment verified the efficiency of the new model and the algorithm. The research result can provide theoretical and technical support to the analysis of transit flow with multiple modes. [ABSTRACT FROM AUTHOR]

Lead users are the group of most valuable users in product innovation and new product development for a certain firm. Based on web mining methods on user innovation communities, this paper presents quantitative methodology to evaluate the contributions and values of online community users to identify lead users. Firstly, we analyze user behaviors and calculate the user interest index (UII) of posts, keywords and innovation fields to measure the popularity of innovations based on other users' focus. Secondly, the model of User Innovation Knowledge supernetwork (UIKSN) is proposed, in which UIIs and user contributions are considered as two types of node weights for integrating behavior data and content data. And then, rules and methods are suggested based on the UIKSN model for identifying lead users to meet various requirements including contributions and UIIs in posts, keywords, hot frontiers, core innovation fields, and even in certain fields or knowledge points. Furthermore, knowledge structures are analyzed through ego-network analysis. Case studies show that the proposed UIKSN model and methodology are more objective and credible and thus have good potentials for identifying and analyzing lead users from multiple levels, such as posts, keywords, hot front, core innovation fields, etc. [ABSTRACT FROM AUTHOR]

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.

• Propose a new household activity-based network equilibrium model that takes into account the interactions between household members by heterogeneous household type with different size for making choices on daily joint/solo activities and travel in congested road networks. • Introduce two new household-oriented network equilibrium principles based on household optimum and household-based system optimum, together with the formulations of their equivalent mathematical programming problems, and their analytical relationships to the conventional user equilibrium (individual optimum) and individual-based system optimum. • Propose a new supernetwork platform for converting the time-dependent household daily activity-travel scheduling problem into an equivalent static traffic assignment problem within a unified modeling framework. • Provide two numerical examples to illustrate the merits of the proposed model together with the key insights from the results. This study proposes a new household optimum (HO) utility approach to model the intra-household interactions between household members by heterogeneous household type with different size in deciding their daily joint/solo activities and travel in congested road networks. In contrast to the conventional approach based on selfish choices of individuals to maximize their own utility, the proposed approach considers the activity-travel choices of all household members to maximize their household utility. Based on the HO utility approach, a new household activity-based network equilibrium model is proposed to simultaneously take into account the time-dependent household daily activity-travel scheduling and traffic assignment problems within a unified modeling framework. Two new household-oriented network equilibrium principles, namely, HO and household-based system optimum (HSO), are introduced together with the formulations of their equivalent mathematical programming problems. The analytical relationships between HO, HSO, conventional user equilibrium and individual-based system optimum, and their properties are then investigated. The proposed model is formulated as an equivalent variational inequality problem and solved by a diagonalization method in a supernetwork platform. Numerical examples are provided to illustrate the merits of the proposed model, together with the key insights of the results that highlight the importance of considering joint activities and travel in travel demand forecasting and transportation network design. [ABSTRACT FROM AUTHOR]

Qi, X. and Xiao, W., 2019. Identifying the evolutionary path of maritime industries from the perspective of supernetwork. In: Hoang, A.T. and Aqeel Ashraf, M. (eds.), Research, Monitoring, and Engineering of Coastal, Port, and Marine Systems. Journal of Coastal Research, Special Issue No. 97, pp. 131–135. The 21st century is the century of the ocean. The ocean contains precious treasures for sustainable development of human. The marine economy is a dynamic and complex system across industries and regions. The restructuring of the industrial chain in the marine economy, the changes in enterprise alliances and the adjustment of regional functional orientations will all change the marine economic system. How to predict the development trend and evolution law of the marine industry is the premise and basis for scientific decision-making in the marine economy. This paper constructs a supernetwork model of the marine industry. On this basis, a hypertriangle is used as a measure of structural similarity, and a method for calculating the superedge similarity matrix is proposed. According to the correspondence between the superedge and the nodes, the probability of future link between the two industries in the supernetwork of marine industry is determined to study the future evolution path of the marine industry. The empirical results show that the proposed method for evolution path of the marine industry has certain scientificalness and rationality. [ABSTRACT FROM AUTHOR]

Joint travel problem (JTP) is an extension of the classic shortest path problem and relevant to shared mobility. A pioneering endeavor via supernetwork framework has been put forward to model two-person JTP. However, it was only addressed in the static context and with the assumption of zero waiting disutility, which resulted in no or weak synchronization among the travelers. This paper proposes a space–time multi-state supernetwork framework to address JTP for conducting one joint activity in the time-dependent context. Space–time synchronization and various choice facets related to joint travel are captured systematically. Two-person JTP is first discussed in a uni-modal transport network, and further extended to incorporate multi-modal and multi-person respectively. Stage-wise recursive formulations are proposed to find the optimal joint paths. It is found that JTP is a variant of Steiner tree problem by reduction and the number of meeting/departing points has no impact on the run-time complexity in space–time multi-state supernetworks. [ABSTRACT FROM AUTHOR]

The interaction of public opinion exists in both the real space and the virtual space. To specifically study the evolution process of public opinion in the two spaces, we first analyzed the characteristics of the evolution of public opinion in different spaces and the link between them in the process of evolution.Then, combined with the improved Hegselmann-Krause(HK) model, the online and offline public opinion evolution model based on the supernetwork was constructed. We also proposed a simulation system framework including initialization module, information propagation and interaction module and synchronization module. According to the direction of synchronization, two kinds of synchronization rate, real space-virtual space and virtual space-real space were proposed. Finally, through simulation experiments, the influence of synchronization ratio and space velocity radio on the evolution of public opinion was discussed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

For the realization, a qualitative and quantitative description of matching degree between the elements for logistics supply network and demand network, logistics super network models are constructed by the theory of super network. Faced with the problems of diverse demand and massive circulation for commodities, this article studies the structure of the logistics super network of multi-commodity circulation and establishes the continuous cost function of the logistics demand and supply, reflecting the logistics cost of different commodities in different phrases. This article aims to establish the optimization model of logistics supernetwork by aiming to maximize the matching of supply and demand of multi-commodity. The model is transformed into the variational inequality problem, and proves the existence and uniqueness of the equivalence solution. Use the case of the logistics supernetwork of coal, a modified projection algorithm is adopted and the fact is revealed that improving the supply capacity of the network matching may have the original 81.3% increase to 90.5%, improving the impact of the relationship between trades, matching degree can be increased to 90.1%. [ABSTRACT FROM AUTHOR]

As the most important intangible resources, knowledge have been widely concerned among scholars, especially in knowledge expression and excavation using knowledge network. However, these homogeneous, static network can't adequately describe the knowledge elements and their variations. To solve the problem of heterogeneity, an evolving hyper-network model was constructed to meet with mechanisms of knowledge growth and fading in mass collaborative innovation community. Based on some topological properties of this model, we analyze the distribution characteristics of knowledge in community, and proposed a novel classification method. Finally, a case study is given to demonstrate the proposed method. And several management suggestions accordingly are proposed by analyzing different types of knowledge from real data. This article provides a methodological guidance for innovation knowledge discovering and precision management in community. [ABSTRACT FROM AUTHOR]

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.

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. [ABSTRACT FROM AUTHOR]

A weapon system of systems (WSoS) is a collection of interdependent systems providing multiple interdependent capabilities to support multiple tasks. In this paper, we propose a WSoS scheme generation method based on a granular analysis of a WSoS supernetwork. More precisely, we establish a WSoS supernetwork model based on a “network-centered” combat mode. Next, based on the theory of quotient space, a granular analysis is presented to reduce the complexity of the WSoS scheme generation. Then, the WSoS supernetwork is converted into a directed weighted network with multiple granularities, and an algorithm for the WSoS scheme generation based on the directed weighted network is presented. Consequently, each WSoS scheme corresponds to a path in the directed weighted network, and the capability of supporting the realization of a task by a WSoS can be analyzed based on the schemes. Finally, the feasibility of the proposed approach is demonstrated using an illustrative example. [ABSTRACT FROM PUBLISHER]

As valuable resources for incubating firms, knowledge resources have received gradually increasing attention from all types of business incubators, and business incubators use a variety of knowledge services to stimulate rapid growth in incubating firms. Based on previous research, we generalize the knowledge transfer and knowledge networking services of two main forms of knowledge services and further divide knowledge transfer services into knowledge depth services and knowledge breadth services. Then, we construct the business incubators’ knowledge supernetwork model, describe the evolution mechanism among heterogeneous agents and utilize a simulation to explore the performance variance of different business incubators’ knowledge services. The simulation results show that knowledge stock increases faster when business incubators are able to provide knowledge services to more incubating firms and that the degree of discrepancy in the knowledge stock increases during the process of knowledge growth. Further, knowledge transfer services lead to greater differences in the knowledge structure, while knowledge networking services lead to smaller differences. Regarding the two types of knowledge transfer services, knowledge depth services are more conducive to knowledge growth than knowledge breadth services, but knowledge depth services lead to greater gaps in knowledge stocks and greater differences in knowledge structures. Overall, it is optimal for business incubators to select a single knowledge service or portfolio strategy based on the amount of time and energy expended on the two types of knowledge services. [ABSTRACT FROM AUTHOR]

Comparing with single complex networks, supernetworks are more close to the real world in some ways, and have become the newest research hot spot in the network science recently. Some progresses have been made in the research of supernetworks, but the theoretical research method and complex network characteristics of supernetwork models are still needed to further explore. In this paper, we propose three kinds of supernetwork models with three layers based on the unified hybrid network theory framework (UHNTF), and introduce preferential and random linking, respectively, between the upper and lower layers. Then we compared the topological characteristics of the single networks with the supernetwork models. In order to analyze the influence of the interlayer edges on network characteristics, the cross-degree is defined as a new important parameter. Then some interesting new phenomena are found, the results imply this supernetwork model has reference value and application potential. [ABSTRACT FROM AUTHOR]

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.

Binets and trinets are phylogenetic networks with two and three leaves, respectively. Here we consider the problem of deciding if there exists a binary level-1 phylogenetic network displaying a given set $$\mathbb {T}$$ of binary binets or trinets over a taxon set X, and constructing such a network whenever it exists. We show that this is NP-hard for trinets but polynomial-time solvable for binets. Moreover, we show that the problem is still polynomial-time solvable for inputs consisting of binets and trinets as long as the cycles in the trinets have size three. Finally, we present an $$O(3^{|X|} poly(|X|))$$ time algorithm for general sets of binets and trinets. The latter two algorithms generalise to instances containing level-1 networks with arbitrarily many leaves, and thus provide some of the first supernetwork algorithms for computing networks from a set of rooted phylogenetic networks. [ABSTRACT FROM AUTHOR]

Complex mechanical products are a priority area of advanced manufacturing strategy in the USA and Europe. Excellent models for design processes of complex mechanical products are essential for managers or designers to manage design processes and further improve design efficiency. Multiple elements and complicated relationships between elements in the design processes of complex mechanical products cause difficulties in systematically and quantitatively expressing the design processes. Therefore, we put forth a supernetwork-based model for designing complex mechanical products. First, we identified the key elements in the design processes of complex mechanical products. Next, based on this we analyzed sub-elements of the key elements and relationships between sub-elements. Then we built sub-networks with sub-elements as nodes and their relationships as edges and the supernetwork model for design processes of complex mechanical products based on the sub-networks and their relationships. Meanwhile, we also present a method for combining linguistic variables with the corresponding triangular fuzzy numbers, and a max/min synthesis method to accurately compute the edge weights. Finally, we suggest the practical applications of the proposed model and give a comparison of the proposed model and existing ones to verify the feasibility and validity of this study. [ABSTRACT FROM AUTHOR]

Phylogenetic networks are a generalization of evolutionary trees that can be used to represent reticulate processes such as hybridization and recombination. Here, we introduce a new approach called TriLoNet (Trinet Level- one Network algorithm) to construct such networks directly from sequence alignments which works by piecing together smaller phylogenetic networks. More specifically, using a bottom up approach similar to Neighbor-Joining, TriLoNet constructs level-1 networks (networks that are somewhat more general than trees) from smaller level-1 networks on three taxa. In simulations, we show that TriLoNet compares well with Lev1athan, a method for reconstructing level-1 networks from three-leaved trees. In particular, in simulations we find that Lev1athan tends to generate networks that overestimate the number of reticulate events as compared with those generated by TriLoNet. We also illustrate TriLoNet’s applicability using simulated and real sequence data involving recombination, demonstrating that it has the potential to reconstruct informative reticulate evolutionary histories. [ABSTRACT FROM AUTHOR]

Microblog public opinion field gradually becomes a hotbed of emergency online public opinion. It plays an important role in the formation and evolution of public opinion. This paper analyzes the formation and evolution of emergency public opinion from the research perspective of microblog public opinion field. First, using supernetwork modeling theory, building the microblog public opinion field supernetwork model on the set of social, informational, psychological, opinions subfield together, conducting model analysis on the relationship between internal and external subfields; then, proposing measurable index of microblog public opinion field supernetwork model, analyzing the intensity of microblog public opinion field for using the index; finally, using social computing and data mining algorithms, analyzing the process that microblog public opinion field affects the ignorant and infected and the evolution of public opinion in the microblog public opinion field after the process quantitatively. In order to predict and forewarn the trend of emergency public opinion, provide theoretical basis for intervention and governance of emergency public opinion, and guide the healthy development of emergency public opinion effectively. [ABSTRACT FROM AUTHOR]