Calculation of minimal dominating set in wireless sensor network with host switch-on/off

Abstract

Abstract：This paper proposes a simple and efficient distributed algorithm for calculating minimal dominating set in wireless sensor network. This method can avoid maintaining the connectivities between backbone hosts. Considering that the hosts in mobile networks have different characteristics, this paper proposes a method of calculating minimal dominating set with weight. The nodes can be chosen to form a minimal dominating set when the network topology changes. For the host switch on/off operation, the updating algorithm was provided. The change in the status of a host affects only the status of hosts in the restricted vicinity. Simulation results show that the proposed method can ensure fewer dominators but with higher weight to form the minimal dominating set and the nodes can be adaptive to the changes of network topology. Keywords：wireless sensor network; virtual backbone; minimal dominating set; switch-on/off Wireless sensor network (WSN) can be flexibly and quickly deployed in many applications such as automated battlefield operations, search and rescue, and disaster relief [1] . Routing in WSN is a special challenge. Traditional routing protocols in wired network, which generally use either link state [2,3] or distance vector [4,5] , are no longer suitable for WSN. Routing information has to be localized to adapt quickly to the host switch-on/off changes. Refs.[6] and [7] provided a simple and effective method to construct the minimal connected dominating set (MCDS). Routing based on MCDS makes the routing process be simplified to a subnet. MCDS applied as a foundation of hierarchical routing can effectively find routing and reduce communication latency. When the entire network topology changes, only the local state information of nodes needs to be modified.If the network topology changes too fast, the host switch-on/off operation will have an impact on neighboring nodes, which makes maintaining the connectivity of the connected dominating set and updating routing tables become more complex and difficult. Most MCDS algorithms are rarely involved in updating and maintaining problems. This paper presents a minimal dominating set algorithm in WSN. Virtual backbone network with minimal dominating set is constructed. Considering different characteristic among the hosts in WSN, this paper presents a minimal dominating set algorithm with weight. This method can avoid sustaining the connectivity between backbone nodes. The updating algorithms is also discussed, when topology changes, the backbone network can be rapidly reconstructed and facilitate maintenance. In addition, the locality of hosts status update is verified. Model establishmentA simple undirected graph G = (V, E) is adopted to represent WSN, where V is a node set, and each node represents a sensor node; E is an edge set, each edge e = (u, v) ∈ E (u, v∈ V) indicates that both nodes u and v are within their wireless transmitter ranges, i.e., the connectivities of nodes are based on geographic distances of nodes. ( represents the open neighboring set ...

A Novel Steady-State Simulation Approach for a Combined Electric and Steam System Considering Steam Condensate Loss

“…According to the conservation of momentum, the momentum change in the steam micro-element equals the total impulse of all external forces exerted on the micro-element. The momentum conservation equation for unstable steam flow can be written as Equation (2): [15] ∂(ρu) ∂t…”

“…There are mainly three modes: overhead laying, direct buried laying, and pipe trench laying. The detailed calculation methods are given in [15].…”

“…For the tree network verification, the case is built based on the data of District 1 of the Tianjin Airport Industry Park (data is available in [15]). The case is a nine-node double-heatsource simplified tree network, considering the other districts of the park as equivalent heat loads to the corresponding node.…”

“…The calculated result is shown in Figure 11. SynerGEE gas is a relatively accurate commercial simulation software of the thermal system [15]. Using the simulation results of SynerGEE gas as a benchmark, flow verification of the proposed steam network model is carried out.…”

“…Therefore, this model is more applicable to a single pipeline rather than networks with a complex structure. The authors of [15] fully considered the generation of condensate and heat dissipation along the pipe when modeling and simplified the model using the properties of saturated steam. However, the simplified model equation contains the non-integral power of the steam pressure, which has limitations regarding further transplantation of the model in the optimization, planning, and coupling with other energy networks.…”