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In this paper, by utilizing fluid approximation, we develop a fluid model for an ICN (Information-Centric Networking) network comprised of multiple entities, multiple routers, and multiple repositories, at the transport level. Since ICN is a more complicated network architecture than IP and the complex interaction among content caching, request packet aggregation, and the behavior of a transport protocol must be considered, ICN requires more complicated modeling approach than IP. In the literature, several mathematical analyses of transport protocol for ICN have been performed. However, these mathematical analyses cannot be utilized to analyze the dynamics of transport protocols in ICN because these studies focus on steady state characteristics. In this paper, we develop a fluid model of a large-scale ICN network, by constructing network component models (i.e., entity, router, and repository) with uniform inputs and outputs (i.e., receiving and sending rate of request packets and content packets).

State estimation in active distribution networks which is the heart of energy management central is of great importance. Considering the increase in complexity and realtime management of active distribution networks, knowing network information at each time instant is one of the important measures for exploitation, control and protection of these networks. In this paper, state estimation in unbalanced three phase networks is investigated. In order to obtain a high accuracy procedure which is close to reality, elements comprising distribution network should be modelled accurately. In this paper, different components including line, transformer, load and regulator are modelled. In addition, equations regarding real and virtual measurements used in state estimation of three-phase networks are given. Then, network component and measurement modelling in standard IEEE 13-bus network is implemented and simulated.

This paper shows an analysis of the time offset error introduced into a highly accurate packet-based time synchronization link by the most frequently deployed long distance network components. Translating the sub-nanosecond accuracy of a White Rabbit timing link into long distance fiber communication networks is a very demanding task. With the increased distance the need for devices that keep the integrity of the signal and maintain its power across hundreds of kilometers is beyond question. Some of these devices might suffer from large disparities in their environmental conditions due to being placed in distant locations from each other, potentially varying their behavior. The results demonstrate that moderate temperature disparities can lead to timing offset errors of several nanoseconds. This outcome can be seen as the foundation laid for a series of compensation techniques to be developed in future work.

Based on topological and functional natures of the expressway networks, this paper uses the graph theory and builds up the concept of expressway networks, and defines the network component nature. By referring to the risk theory, it analyzes the content of topological risk of expressway networks and builds the topological risk measures including the heterogeneity measures, connectivity measures and survivability measures. In view of the interconnected relationship between topological risk measures, a method framework oriented assessment of topological risk of expressway networks is established. Combining the situation of the project, setting the expressway networks of Beijing, the results suggest that the topological risk measures can reflect the risks in the expressway networks structure level, the risk evaluation results are in accordance with the real situation of expressway networks.

Ground-Air coordination is a very complex environment for a machine learning algorithm. We focus on the case where an Unmanned Aerial Vehicle (UAV) needs to support a group of Unmanned Ground Vehicles (UGVs). The UAV is required to broadcast an image that contains all UGVs, thus, offering a bird-eye-view on the group as a whole. The source of complexity in this task is twofold. First, coordination needs to occur without communication between the UAV and UGVs. Second, the ability of the UAV to sense the UGVs is coupled with the ability of the UAV to learn how to track laterally the UGVs and adapt its vertical position so that the images of the UGVs are appropriately spaced within the camera field of view. In this paper, we propose using the Deep Actor Network component of an Actor-Critic Deep Reinforcement Learning architecture as a supervised learner. The advantage of this approach is that it offers a step towards autonomous learning whereby the full Actor-Critic model can be utilized in the future. Human demonstrations are collected for the deep Actor network to learn from. The system is built using the Gazebo Simulator, Robot Operating System, and the OpenAI Gym. We show that the proposed setup is able to train the UAV to follow the UGVs while maintaining all UGVs within camera range in situations where UGVs are performing complex maneuvers.

This paper presents an analysis methodology to consider the effects of customer-side battery energy storage systems (BESS) on electricity distribution networks motivated by power-based tariffs. The paper describes the methodology by which the network effects can be defined. The methodology is verified by applying actual distribution network and load data. The analysis shows that transition from traditional energy-based distribution tariff to power-based tariff can lead to an accelerating increase in the application of customer-side energy storages. The results indicate that the network effects of the BESS are significant. The effect of energy storages depends partly on the voltage level of the network component. The results show that peak loads decrease in the case electricity distribution network. The most significant decrease, over 10% on average, is found in the low-voltage network, which is not a minor improvement.

In this paper, we propose a two-phase method to solve the problem of the network component insertion for 3D application-specific Network-on-Chip (NoC). A model based on genetic algorithm is conducted at the first phase, in order to obtain optimal insertion positions of routers and network interfaces with minimal total network interconnection power consumption. Then some routers are merged to further reduce the power consumption and resource costs. Experimental results on several multimedia benchmarks show that, compared to the random insertion method, our method saves about 38.9% of the total network interconnection power consumption on average, and also reduces the resource costs.

This paper examined the social network construction mode based on connected network component under dynamic alliance environment. We assume that firms in one industry participant in alliances dynamically and simulation results show how the alliance network factors influence the social network information sharing performance. Four propositions in a long-term and no extreme value context are built: first, the probability an incumbent is chosen to become a member of a new alliance has a inverted U-shape effect on information sharing performance; second, the probability that the alliance being assembled will include a previous collaborator of an incumbent on the alliance has a inverted U-shape effect on information sharing performance; third, the initiate alliance size has a positive effect on information sharing performance; fourth, the max time during which a firm is not in any alliance has a positive effect on information sharing performance.

A vertically stacked optical banyan (VSOB) network is attractive for serving as the optical switch architecture due to its small depth and absolute signal loss uniformity. A plane fixed routing (PFR) algorithm with optimal time complexity was proposed recently for rapid connection setup in a rearrangeable VSOB architecture. In this paper, we conduct the performance analysis of a high-speed PFR-based VSOB network and introduce an analytical model on blocking probability of the network when component failures (link failure and switching element failure) are considered. Simulation is conducted to verify the model, in which the simulation results show that the proposed analytical model can accurately describe the blocking behavior of a high-speed PFR-based VSOB network. The model significantly contributes to the related areas by providing network developers a quantitative guidance to determine the effects of adopting high-speed PFR algorithm, network component failures and workload variation on the blocking behavior of a VSOB network.

Errors in network components can have disastrous effects so it is important that all aspects of the design are correct. We describe our experiences formally verifying an implementation of an Asynchronous Transfer Mode (ATM) network switching fabric using the HOL90 theorem proving system. The design has been fabricated and is in use in the Cambridge Fairisle Network. It was designed and implemented with no consideration for formal specification or verification. This case study gives an indication of the difficulties in formally verifying real designs. We discuss the time spent on the verification. This was comparable to the time spent designing and testing the fabric. We also describe the problems encountered and the errors discovered. >

We address the problem of designing a TCP/IP based VOD system over a dedicated network. Despite of the general belief that TCP/IP is not suitable for real-time multimedia applications, after testing in a laboratory environment for one year, we are confident in announcing that our prototype is both efficient and reliable. This success depends on several important factors. First of all, the system operates on a dedicated network in which there exists no other traffic except a small amount of background traffic generated by the Ether Switch, the major network component used by our prototype. Second, the system overhead due to the VOD server and the network adaptor card is minimized. Third, we maximize the disk bandwidth by implementing a proprietary disk file system. Our experiment shows that it requires only about 330 KBytes at the client buffer to smooth packet delay jitters.

The paper presents an investigation of manageability, expressional force, and conciseness of planning criteria for electrical power systems. Criteria are classified according to contingency- and customer-focused and in deterministic and probabilistic criteria. A short description is given. A number of actual German power systems with voltage levels from U/sub n/=20 kV up to U/sub n/=380 kV are investigated. Several variations of the criteria with respect to the network component types and remedial measures have been analyzed and compared. Additionally, the investigated probabilistic indices are compared by applying a significance test method. The results show that the international, widely used (n-1)-criterion is sometimes less restrictive than the investigated contingency-focused, probabilistic criteria.

A distributed teleoperating system has been designed and simulated with model-based supervisory control for reduced human attendance and dual sensory feedback channels of model-based, top-down image processing and global positional system (GPS) for robust vehicle pose recovery. The distributed network component design and 3D model display are based on currently available technologies. The most difficult design aspect is to achieve smooth integration between web technologies and the hardware physical entities. Constraints from the remote environment are carefully considered, since the system will be used to build a lava-diverting dam at the base of an active volcano in Japan.