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Summary: The conventional backward/forward sweep method, used for solving the load flow, is only applicable to radial systems. A new load flow method is proposed in this report for islanded droop‐controlled meshed AC microgrids, where the backward/forward sweep (BFS) method is proposed in conjunction with a loop‐breaking approach to determine the power flows for meshed micro‐grids. The proposed approach is applied to the 33‐bus test system, and the recorded results are validated with simulation results obtained from PSCAD/EMTDC software. These recorded results confirm that the proposed method is accurate, and it can be used as a tool in the analysis and planning of meshed microgrid systems. [ABSTRACT FROM AUTHOR]

ABSTRACT Information/secret leaking cannot always be recorded in digital log files. In other words, in log files, not all information/events are recorded, and it is thus impossible to trace the paths of secret leaking on the basis of log files alone. In this paper, to resolve the difficulty of the lack of information, we utilize user-relationship graphs, or social networks, to compensate for the required information. We also utilize a probabilistic analysis to build virtual links to follow information flows. User-relationship graphs are constructed from several flow-net data structures over a longer period so that we can avoid missing embedded threats such as hostile codes. We call this approach virtual flow-net. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Accountability is a very important topic for computer and networking systems. It helps to answer questions such as, 'What happened?' and, 'Who did it?' These two questions are also related to forensics; however, forensics normally tries to answer these questions by adding some human factors (such as a guess or an instinct due to missing evidence, as well as human involvements) under the available system. Accountability, on the other hand, can only be achieved by significantly improving the current system with the result that forensics becomes trivial in an accountable system. Furthermore, each entity in the system must be held responsible for its activities. In order to provide accountability, a better logging system is necessary so that not only their activities but also their relationships may be captured. To this end, our previous work proposed a novel logging mechanism, flow-net methodology, for accountability. In this paper, we extend the flow-net methodology and present its design and implementation in wireless networks. We also evaluate the performance of flow-net and compare it with that of audit log files. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a complete model of collector system layout optimization for offshore wind farms, which consists of both internal and external designs. The internal design uses the algorithm of self‐tracking minimum spanning tree (ST‐MST) combined with added functions of automatic cable selecting (ACS) and cable crossing avoiding (CCA) to form a radial topology. In addition, the features above are also integrated with the use of direct current transmission in the external design, which applies a self‐designed searching method to find the optimal locations for VSC converters. The internal and external designs constitute the whole model of the offshore wind farm. More specifically, the internal connection begins with the Fuzzy C‐means clustering method to divide the farm into clusters, where each center of the cluster locates a substation connecting to the turbines belonging to it. The external connection of the wind farm considers the use of high voltage direct current, which saves a great amount of reactive power in long distance transmission. Both the internal and external designs apply ST‐MST with ACS and CCA, while the external connection is also given a higher priority as it uses the cables with larger cross sections compared with internal connection. [ABSTRACT FROM AUTHOR]