{'fraction_non_alphanumeric': 0.022753128555176336, 'fraction_numerical': 0.01820250284414107, 'mean_word_length': 4.7894736842105265, '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}}
Design of the Sound Insulation Chamber for Stored Grain Insect Sound Detection

A six cubic meter sound insulation chamber is designed based on the principle of double-layer wall sound insulating and porous absorption with the characteristics of stored grain insect action sound. With 3 mm thick plywood as wall material, double - layer spacing 0.08 m, the outer wall being bored, each aperture 1mm, average spacing 1.5 cm, and the hard sound-absorbing material being filled in the two layers, a quasi - double layer perforated structure is built. The ambient noise is uniformly insulated between 125Hz and 2000Hz, and the average sound insulation is about 22dB, and it meets requirements of stored grain insect action sound for the spectrum and SPL. The result shows that the sound insulation chamber has the advantages of small size, economy, and good sound insulation effects.