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In order to explore a new mode of resource utilization of Pueraria root residue, a pilot vermicomposting indoor experiment was carried out using Eisenia fetida for bio-transformation of freshly decomposed Pueraria root residue and fresh Pueraria root residue mixed with cow dung at different ratios. The effect of decomposed Pueraria root residue and the effects of different ratios of Pueraria root residue and cow dung on the growth and reproduction index of earthworm were analyzed. The changes in fertilizing properties of the materials were analyzed before and after vermicomposting, and seed germination was evaluated to determine the effect of vermicomposting. The results showed that fresh Pueraria root residue and decomposed Pueraria root residue alone were not conducive to the growth and reproduction of earthworms. Earthworms were able to grow and reproduce normally in fresh Pueraria root residue mixed with cow dung, which a mixture of 10% fresh Pueraria root residue and 90% cow dung was the most favorable to earthworm reproduction. After earthworm composting, the total organic matter content decreased significantly, the total nutrient content increased significantly, and the seed germination index increased to a certain extent. The total nutrient content of a mixture composed of 70% fresh Pueraria root residue and 30% cow dung was 102.2 g·kg-1 and 57.7% higher than that of a mixture of 10% fresh Pueraria root residue and 90% cow dung. The earthworm bio- treatment technology can be applied to the production of fertilizer from Pueraria root residue. A mixture of 70% fresh Pueraria root residue and 30% cow dung delivers the optimal conditions for earthworm composting.

Oil-water relative permeability curves are the characteristic curves of evaluating the oil-water infiltrating fluid and also are an important part of reservoir engineering studies. Through a large number of core flooding experiments, based on the establishment of oil-water relative permeability calculation models, the use of the function of the relative permeability curves divided these into the water phase concave, water phase convex and a water phase linear categories. The relationship between different types of relative permeability curves with reservoir characteristics, moisture content, common infiltration points, common permeation range and oil displacement efficiency have been evaluated. Analysis the distribution of the reservoir usable remaining oil and reservoir irreducible oil of different types of relative permeability curves.

For real-time applications in mobile low-duty-cycle (DC) wireless sensor networks (WSNs), discovering neighbours needs to be achieved in both short average latency and high fraction of discoveries (FDs) with low energy consumption. A novel asynchronous probabilistic method is proposed, in which a node randomly chooses a prime, e.g. p, from a pre-configured prime set and wakes up only at the first slot during every p continuous slot which is for a hyper-cycle length, i.e. a fixed number continuous slots, determined by the prime sets, and then selects another prime for the next hyper cycle. For low-DCs, especially

A novel probabilistic algorithm for low duty-cycle dynamic (mobile sensors) wireless sensor networks (WSNs) is proposed. The rapid development of smart phones and mobile sensors had fostered a demand for opportunistic encounter-based networking to support mobile social networking and proximity-based gaming. However, the performance of such applications was restricted by a lack of specialised neighbour discovery algorithms. For existing algorithms, even though the probabilistic algorithms have good performance in average discovery latency, when working with a low duty-cycle, the performance is not so encouraging. Deterministic algorithms can provide bound time for the worst discovery latency, but they sacrificed the average discovery latency. In response, a novel prime-set-based neighbour discovery algorithm (PSBA) is proposed. The PSBA is a probabilistic algorithm tailored to low duty-cycle dynamic WSNs. Leveraging on the certainty of the deterministic algorithm and the randomness of the probabilistic algorithm, the inherent long tail of the probabilistic algorithm can be improved. Also, the average discovery latency of the PSBA can be drastically reduced compared to existing algorithms, which precisely meets the requirements in low duty-cycle dynamic WSNs.

A novel distributed range-free localisation algorithm, named polygonal overlapped possible area (POPA), is proposed to accurately localise an unknown node. First, for an unknown node, to theoretically define its possible localisation area (PLA), virtual radiation regions of its n th-hop anchor neighbours are introduced. Then an effective area-splitting algorithm is employed to simplify and speed up the computation of the possible localisation area. Simulation shows localisation error can be controlled within 20% with off-the-shelf devices.