This paper presents an intelligent approach for modeling Routing in wireless sensor networks. A new routing protocol based on Artificial Bee Colony algorithm is introduced in this paper for solving delay-energy trade-off problem. In the proposed approach every food source represents a possible and feasible candidate path between each original and destination node. The positions of food sources are modified by some artificial bees in the population in order to discover the places of food sources. The food source with the highest nectar value seems to be a solution which is evaluated by the fitness function. Obtained simulation results show that the proposed protocol can achieve good trade-off between routing delay and energy .

High-pressure deep shale gas reservoirs are usually highly stress-sensitive. When the reasonable production mode of shale gas well is built, the impact of strong stress sensitivity should be fully considered. First, this study calculated the relationship between permeability and formation pressure under different elastic modulus based on the shale lithology of Long Ma Xi formation in Sichuan Basin by testing and analysing the mechanical parameters of the rock. According to numerical simulation result, when the elastic modulus exceeds 14.0 GPa, the stress sensitivity of the matrix will slight affect the cumulative gas production of shale gas. Second, the changing relation between fracture conductivity and permeability with fracture pressure and the time of pressure acts were experimentally studied. The numerical simulation result suggested that the 30-year cumulative gas production considering the stress sensitivity was reduced by 13.5% compared with the 30-year cumulative gas production without considering the stress sensitivity. Finally, the production of different production modes under different stress sensitive characteristics was predicted using numerical simulation method. When the matrix and fractures are fixed with a same stress-sensitive curve, the initial production allocation will not significantly impact the cumulative gas production. When the fractured fractures are subjected to a varying stress sensitive curve, the lower production allocation will result in higher post-production and cumulative gas production.

No abstract

In this paper, the optimization of context weighting coefficients are studied and the objective of the optimization is to find a group of weighing coefficients, such that the code length ofsource symbols occurred before the current symbol can be minimized. Multivariant optimization algorithm is used to find the solution of this multimodal optimization problem. With this context weighting algorithm, the compression efficiency is improved.

No abstract