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In this paper, an Energy Consumption (LEACH-ECD) based routing protocol is presented. Node's residual energy during cluster-heads election is considered in LEACH-ECD. The scale of the clusters is limited by setting the optimal number of cluster-heads. And an assistant node in each cluster is selected to share the communication load within the cluster. During inter-cluster data transmission, the cluster-head computes its own energy guiding factor to determine the mode of communication. By combining single-hop and multi-hop communication modes, the energy consumption of the whole network is reduced and the lifetime of network will be extended and the reliability of data transmission will be increased.

The monitoring system in coal mine has special requirements for data query. Analysis shows that routing in the system should have four features: data-centric routing, supporting query of geographic position, low delay and high reliability of data transmission, robustness of topology. A mobile agent based routing algorithm with mobile sink and a dynamical weight metric which is derived from its current position and some QoS parameters is presented to meet the above-mentioned features. The mobile agents can determine their own routes and apply mobile sinks when topology changes. Simulation results show that the route algorithm can reduce high delay and low reliability of the monitoring system in coal mine.

As technology scaling progresses into 65nm node and below, On Chip Variation (OCV) specifically thickness variation due to Chemical Mechanical Polishing (CMP) processes becomes relatively larger, as such it needs to be taken into consideration into post layout RC extraction and timing flow. Traditionally manufacturing effects due to lithography and CMP processes are captured using rule based look up tables which are generally included in the technology files of the RC extraction tools. However, due to complex nature of the CMP process and its design dependency, the generic rules can not capture thickness variation for various design topology accurately. Therefore CMP models are used to simulate design specific thickness variation profile, based on the calibrated manufacturing process. In this paper, we demonstrate that by incorporating CMP model in the post layout RC extraction flow, the thickness variations are reflected more accurately. Therefore, the capacitance values extracted are different from those obtained using rule based approach. As a result, new timing violations are detected using model based approach.

As technology scaling progresses into 65 nm and below nodes, on chip variation (OCV) specifically interconnect thickness variation due to chemical mechanical polishing (CMP) becomes relatively larger, as such it needs to be taken into consideration in the post layout RC extraction and timing flow. Traditionally manufacturing effects due to lithography and CMP processes are captured using rule based look up tables. These look up tables are included in the technology file of RC extraction tools. However, due to complex nature of CMP process and design topology, the generic rules can not capture thickness variation accurately. Therefore CMP models are used to generate design specific thickness variation profile, based on the calibrated manufacturing process library. In this paper, we demonstrate that by incorporating CMP model in the post layout RC extraction flow, the thickness variations are reflected more accurately and the capacitance value extracted are different from results obtained using the polynomial equation based approach. As a result, new timing violations are detected with CMP modeling.