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With the rapid development of China's economy, smart grid has been built in an all-round way. As an important basic node of smart grid, the technical complexity of smart substation automation system is getting higher and higher. Once a fault occurs, if not handled in time, it will seriously affect the safety and stability of the power grid, which poses a great loss to economic production activities. The traditional mode of local maintenance has the drawbacks of high time consuming, low efficiency, and heavy workload. To solve these problems, a remote maintenance technology for substation automation equipment based on general service protocol (GSP) is first proposed in this paper, and the brand new system architecture is designed which involves the service management center, the maintenance center, and substations. The standardized interaction mechanism, integrated deep security protection methods, and flow control strategy are adopted to ensure the standardization, security, and reliability of the remote maintenance system. Finally, the effectiveness of the proposed methods is successfully demonstrated, and the comprehensive performance of the remote maintenance system is evaluated by comparing with the traditional local maintenance mode. [ABSTRACT FROM PUBLISHER]

ABSTRACT Our desire to deliver increased functionality while setting tighter operational and regulative boundaries has fueled a recent influx of highly coupled systems. Nonetheless, our current capacity to successfully deliver them is still in its infancy. Understanding how such Designed systems are structured, along with how they compare to their naturally Evolved counterparts, can play an important role in bettering our capacity to do so. Based on this premise, the structural patterns underlying a wide range of seemingly unrelated systems are uncovered using tools from network science. By doing so, structural patterns emerge and are subsequently used to highlight both similarities and differences between the two classes of systems. With a focus on the Designed class, and assuming that increased structural variety fuels design uncertainty, it is shown that their adherence to statistical normality (i.e., expected vs. encountered patterns and statistical correlations between combinations of such patterns) is rather limited. Insight of this sort has both theoretical (context agnostic approaches are increasingly relevant within the domain of Systems Engineering, yet are rarely used) and practical (transferability of knowledge) implications. [ABSTRACT FROM AUTHOR]

ABSTRACT A system's architecture defines its flexibility-the ease with which changes to the system's structure may be made. Systems may possess an internal structure that is relatively complex to describe-especially after many changes. In addition, some changes may require several iterations before stakeholders converge on a final design choice. There is currently no unified mathematical theory that captures these factors. We developed metrics for flexibility, descriptive complexity, and rework potential defined on graph-based representations of a system's structure. We applied these metrics to four idealized generic system architectures: Tree-structured hierarchies are easy to describe and require minimal design iteration. However, they permit relatively few changes, unless the underlying architecture itself is changed. Furthermore, each such change adds significant complexity. Grid networks are more flexible than trees, but also more descriptively complex. Grids also require some degree of design iteration between stakeholders. Teams are extremely flexible but the requirement for consensus (e.g., due to cognitive limits among humans) restricts their size. Layered hierarchies possess moderate flexibility and require fewer iterations than corresponding grids and teams, although they can be difficult to describe succinctly. Our findings suggest that no architecture is ideal under all circumstances; rather, each has strengths and weaknesses that can be exploited in different environments. [ABSTRACT FROM AUTHOR]

Today?s mobile customers desire to remain connected anywhere, at any time, and using any device. This phenomenon has encouraged mobile network operators to build complex network architectures by incorporating new features and extensions, which are harder to manage and operate. In this article we propose a novel and simplified architecture for mobile networks. The proposed architecture, which we call CSDN (Cellular SDN), leverages software defined networking (SDN) and network functions virtualization (NFV). SDN abstracts the network and separates the control plane from the data plane; NFV decouples logical network functions from the underlying hardware, for dynamic resource orchestration. Furthermore, we argue that dynamic resource orchestration and optimal control need real-time context data analyses to make intelligent decisions. Thus, in the proposed architecture we exploit the capability of the mobile edge networks to gather information related to the network as well as the users. This information can be used to optimize network utilization and application performance, and to enhance the user experience. In addition, the gathered data can be shared with third party service providers, enabling the realization of innovative services. [ABSTRACT FROM PUBLISHER]

Graph partitioning is a traditional problem with many applications and a number of high-quality algorithms have been developed. Recently, demand for social network analysis arouses the new research interest on graph partitioning/clustering. Social networks differ from conventional graphs in that they exhibit some key properties like power-law and small-world property. Currently, these features are largely neglected in popular partitioning algorithms. In this paper, we present a novel framework which leverages the small-world property for finding clusters in social networks. The framework consists of several key features. Firstly, we define a total order, which combines the edge weight, the small-world weight, and the hub value, to better reflect the connection strength between two vertices. Secondly, we design a strategy using this ordered list, to greedily, yet effectively, refine existing partitioning algorithms for common objective functions. Thirdly, the proposed method is independent of the original approach, such that it could be integrated with any types of existing graph clustering algorithms. We conduct an extensive performance study on both real-life and synthetic datasets. The empirical results clearly demonstrate that our framework significantly improves the output of the state-of-the-art methods. Furthermore, we show that the proposed method returns clusters with both internal and external higher qualities. [ABSTRACT FROM AUTHOR]

Highlights: [•] SNA as a “cognitive tool” providing data for designing rural development agendas. [•] Description of socio-economic and geographical structure by complete and ego networks. [•] Identification of strategic actors in current and new networks. [•] SNA as an “assessment tool” to evaluate networking projects. [•] SNA as an “awareness tool” to enhance rural actors’ awareness of their relational system. [ABSTRACT FROM AUTHOR]

The 2008 System of National Accounts recognizes capital services as the conceptually correct way to measure the input of capital into production. This allows setting up an integrated system of industry-level and aggregate productivity accounts that are consistent with the 2008 SNA. The paper discusses the new aspects in the 2008 SNA and sets out such an integrated system, based on Jorgenson's aggregate production possibility frontier and gross output-based industry productivity measures. Recent results for industry productivity measures for the United States complete the picture. [ABSTRACT FROM AUTHOR]

GDP, one of the main macroeconomic aggregates specific to SNA represents the synthetic expression of economic activity results produced within the economic territory over a period of time, regardless of the contribution that they had domestic or foreign subjects. [ABSTRACT FROM AUTHOR]

Purpose – The aim of this paper is to present network visualisation as a way to analyse and to test the design of a website. Design/methodology/approach – A network graph of the access to the webometrics.info site from its web logs was analysed. Several graphs (navigational and query graphs) with different added variables were explored. SNA indicators were used to extract the main findings of these networks. Findings – The results show the double structure of the two language versions, the central position of the search engines as hubs that distribute the access to every page, how the pages are grouped by their thematic and structural relationships, and which pages are less requested through search engines queries or are less visible. Research limitations/implications – The results are based on the web performance of only one website and therefore generalisation has to be cautious. Originality/value – The application of network visualisation and SNA indicators allows to explore the navigation of a website by users and to test how it is used. The graph representation makes possible an intuitive way to observe the structure of a website, the behaviour of users and information consumption. [ABSTRACT FROM AUTHOR]

Central nodes (i.e., prominent actors) in a social network are those that are linked to other nodes in an extensive or critical manner. Therefore, their removal may lead to points of failure. The objective of the present work is to exploit network topology to devise an approach towards: 1) finding a substitute to a deleted node if the latter is a central one; 2) adding appropriate links to maintain the network connected. The approach exploits the role played by nodes to predict the new structure of a social network once one entity disappears. The role of a node in the network is expressed in terms of its centrality in the network. Three important roles are considered: the leader, the mediator and the witness. An entity acts as a leader, a mediator or a witness if it has a high degree centrality, betweenness centrality and closeness centrality, respectively. [ABSTRACT FROM AUTHOR]

Single vendor ATM software applications and monitoring are less complex. However, it takes more time to monitor and update these ATMs with antiviruses and security patches. Closed operating systems like OS/2 were deployed along with X.25 or SNA-based network in single vendor ATMs. Multivendor ATMs were facilitated by central ATM monitoring software and open operating systems like Microsoft Windows with a support of TCP/IP-based networks. This paper discusses the scope and issues of common APIs in ATMs as well as ATM monitoring and application software in both single and multivendor ATMs. It also discusses the emergence of web-enabled ATMs. [ABSTRACT FROM AUTHOR]

Social network analysis (SNA) has been a research focus in multiple disciplines for decades, including sociology, healthcare, business management, etc. Traditional SNA researches concern more human and social science aspects—trying to undermine the real relationship of people and the impacts of these relationships. While online social networks have become popular in recent years, social media analysis, especially from the viewpoint of computer scientists, is usually limited to the aspects of people's behavior on specific websites and thus are considered not necessarily related to the day-to-day people's behavior and relationships. We conduct research to bridge the gap between social scientists and computer scientists by exploring the multifacet existing social networks in organizations that provide better insights on how people interact with each other in their professional life. We describe a comprehensive study on the challenges and solutions of mining and analyzing existing social networks in enterprise. Several aspects are considered, including system issues; privacy laws; the economic value of social networks; people's behavior modeling including channel, culture, and social inference; social network visualization in large-scale organization; and graph query and mining. The study is based on an SNA tool (SmallBlue) that was designed to overcome practical challenges and is based on the data collected in a global organization of more than 400 000 employees in more than 100 countries. [ABSTRACT FROM PUBLISHER]

This article reviews the basic concepts of Social Network Analysis (SNA) and its uses in theoretical and empirical planning literature. Continuing a discussion among planning theorists that was initiated at the 2003 ACSP/AESOP Joint Congress, the authors respond to specific gaps identified in papers presented at that conference. Specifically, the authors review the literature on SNA within disciplines related to planning and empirical planning studies using SNA. The authors find that the knowledge base on SNA specifically and network analysis generally is highly fragmented along disciplinary lines, contributing to the critique that it is a fuzzy concept. [ABSTRACT FROM PUBLISHER]

This study describes an attempt to develop a synthetic route using theoretical calculations, i.e., in silico synthesis route development. The KOSP program created four potential synthetic routes for generating 2,6-dimethylchroman-4-one. In silico screening of these four synthetic routes was then performed. In silico screening involves theoretical analysis of synthetic routes prior to actual experimental work. A synthetic route using the Mitsunobu reaction had already been reported by Hoddgets et al. Theoretical investigations were also conducted on two SNAr reactions as well as a Michael reaction before they were examined experimentally. In silico screening using DFT calculations indicated that only the Michael reaction was likely to produce the target. Experimental work confirmed that the target was obtained in a yield of 76.4% using the Michael reaction. The other two routes, except for the Mitsunobu reaction, failed to generate the target. Our results demonstrate that theoretical calculations can be used to narrow down the number of experiments that need to be conducted when developing novel synthetic routes. [ABSTRACT FROM AUTHOR]

The main conceptual issues in the study of strange nonchaotic dynamics have been summarized and reviewed earlier [Prasad et al., 2001]. In the past five years, there has been further progress in the analysis of such attractors, and in understanding the nature of dynamical transitions in quasiperiodically forced systems. Here we discuss new developments which include the creation of strange nonchaotic attractors in excitable systems, the elucidation of the mechanisms for the intermittent and fractalization routes to SNA as well as their potential applications. The possibility of creating such attractors without recourse to quasiperiodic forcing is an important objective, and this has been realized in specific circumstances. [ABSTRACT FROM AUTHOR]

Finding interaction patterns is a challenging problem, but this kind of information about processes or social networks might be useful for an organization’s management to understand the role of specific persons in processes. Ad-hoc processes are of special interest, because they result from runtime-collaboration between the participants, not using predefined models specifying the persons responsibilities and the order of activities. Because social network analysis (SNA) is closely related to interaction pattern detection, we introduce it as a method to determine properties of social networks like project teams. In order to support the detection of these patterns, we discuss the necessity of additional semantic activity information, and we propose rules and an algorithm that allow detecting such patterns automatically. We apply our algorithm in a case study, using Caramba to perform an example ad-hoc process. [Copyright &y& Elsevier]

The IBM 374x Communication Controllers, and the NCP (network control program) software that runs on them, have been at the center of the IBM SNA (Systems Network Architecture) for many years. However, the 374x hardware is no longer being produced. In order to continue to offer IBM customers various functions provided by the NCP product, IBM has developed a Communication Controller for Linux® (CCL) for the IBM System z™. CCL is a software program that emulates the 374x hardware, enabling the NCP to function in Linux. IBM customers now have the ability to migrate their NCP product to a Linux partition on System z. The current NCP product, running on an IBM 374x Communication Controller, supports both host channel and network attachment. The channel protocol used for the host-channel support is referred to as channel data link control (CDLC). In order to provide the System z9™ host operating systems with the ability to attach to the new CCL NCP over a channel interface, a new channel adapter is required. The new innovative Open Systems Adapter for NCP (OSN) channel support provided by the OSA-Express2 allows various operating systems on the same System z9 to attach "internally" to the CCL without using any external network or channel fabric. [ABSTRACT FROM AUTHOR]

This article presents an analysis of the human to human interactions in two public online newsgroups, one targeting the young generation and the other the elderly. The main goal of this study was to establish a better understanding of similarities and differences in the ways of interacting among the participants of these two newsgroups. A series of analytical/statistical techniques, like Social Network Analysis (SNA), were used in order to get a better understanding of the online communities that have emerged around the participants of these two newsgroups. The SNA analysis showed that the teens newsgroup is more highly connected, has more messages sent and received and has a higher reciprocity. On the other hand, the senior newsgroup has more central dominant people who tend to make the rest of the network dependent on them for communication. [ABSTRACT FROM AUTHOR]

This article presents the structure of Spanish science from 1990 to 2005. Based on ISI subject–category co–citation, including natural sciences, social sciences and arts & humanities, and combining both social network analysis (SNA) and pruning algorithms such as pathfinderߝnetworks (Pfnet) and other information layout algorithms like Kamada–Kawai's, the basic structure of Spanish science is shown through its essential relations. The results are bibliometric–maps (scientograms) revealing the macrostructure, microstructure and the backbone of Spanish science and making possible its analysis and explanation. [ABSTRACT FROM AUTHOR]

This paper introduces the approach of the Systems research Network (SysNet) for land use planning in tropical Asia with a focus on its main scientific–technical output: the development of the land use planning and analysis system (LUPAS) and its component models. These include crop simulation models, expert systems, GIS, and multiple goal linear programming (MGLP) models for land evaluation and optimization. LUPAS was designed as a decision support system (DSS) for strategic land use planning. Integration of LUPAS components in four case studies was performed in a network with national research teams and local stakeholders. This network allowed iterative evaluation and refinement of LUPAS for scenario analysis on technical and policy changes. Several interactive sessions with stakeholders led to more detail in scenarios (goals and constraints), model features and databases. To facilitate negotiation among stakeholders, the MGLP user interface (UI) was developed. In interactive sessions, goal restrictions are tightened to quantify trade-offs between conflicting goals. Choice and degree of tightening reflect the specific priorities for sustainable land use. The development of LUPAS is exemplified for one case study, Ilocos Norte, Philippines. Weak points of the system include inadequate spatial differentiation of socio-economic characteristics, scarce database for quantifying perennials and mixed cropping systems, and insufficient consideration of long-term effects of production technologies on resource quality. However, a promising perspective for effective policy support lies in the possible link of the regional LUPAS approach with farm household models. [Copyright &y& Elsevier]

The work on the introduction of the elements of the SNA into the official statistical practice of the former U.S.S.R. began in 1988 when estimates of the GDP using conversion keys were prepared. In 1991 the decision was made to implement the entire SNA gradually on the basis of the international standards. The methodology of compilation of the main accounts was formulated by the Statistical Committee of the C.I.S. with the assistance of the OECD. It originally drew on the ESA with introduction of elements of the revised SNA and adaption to specific economic processes in the country. It required solution of a number of conceptual and statistical problems referring to the treatment, allocation and valuation of selected activities. The estimates of the main accounts were made for the former U.S.S.R. by sectors and by industries for 1988-90. This project has provided the basis for further work on implementation of the SNA in C.I.S. countries. [ABSTRACT FROM AUTHOR]

The article explores on the development of enterprise computing. Information about the traditional and not-so-traditional enterprise systems for online transaction processing (OLTP) generated through online processes, is provided. Also emphasized is the significant of database management systems and communications software based on systems network architecture (SNA) for enterprise systems. INSET: Historical perspectives.

The evolution of mobile network architecture is an essential part in the development process of the fifth generation (5G) of cellular mobile systems, and that is through the incorporation of advanced cloud technologies and network function virtualization techniques. The new network architecture needs to support a wide range of high data rate applications and services, offering capacities of up to multiple gigabits per second, yet meeting extremely stringent latency and reliability requirements under a diverse variety of scenarios. Thus the automation of network control and overall system management to achieve such an ambitious set of performance targets became crucial. Significant global effort for the necessary new technologies has been initiated. [ABSTRACT FROM PUBLISHER]