{'fraction_non_alphanumeric': 0.018220042046250877, 'fraction_numerical': 0.0, 'mean_word_length': 4.852459016393443, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
A dynamic selection algorithm for extending the lifetime of two-tiered sensor network

In the wireless sensor network, an important problem is that how to improve the network lifetime. In recent years, the proposal of using relay nodes to maximize the network lifetime has been suggested in the literature. It is established that, in a two-tiered sensor network (TTSN), higher-power relay nodes which are responsible for receiving and transmitting data can be used as the cluster heads. However, how to extend the network lifetime in a TTSN in this proposal remains a challenge. In this paper, we propose a new approach termed as DSA, to minimize the energy consumption of maximum energy dissipation relay node, which can greatly extend the lifetime of the Two-Tiered Sensor Network. The Main idea is that dividing the relay nodes into several layers at first and then choosing a best transfer path for every relay node at each layer to extend the lifetime of TTSN. We design an algorithm to implement the idea. The advantage of this novel algorithm in terms of complexity and its capability in extending the lifetime of TTSN has been analyzed in detail. By simulations, we compare our method with the direct transmit energy model, minimum transmission energy model and broadcast incremental power algorithm. Simulation results demonstrate significant improvements have been achieved in our method in terms of lifetime of TTSN.