This paper proposes an effective method for early diagnosis (stress concentrating) of the oil-gas pipeline. Based on the principle of electromagnetic induction Faraday, we have designed and realized the nondestructive testing system for stress concentration area of ferromagnetic materials by means of the research of metal materials inverse magnetostrictive effect mechanism. The system changes the influence degree of the stress in ferromagnetic materials’ magnetic conductance to the corresponding voltage array by using discrete wavelet analysis method to process the data, in which not only the measuring accuracy is improved, but also the stress concentration is more directly reflected. The experiments confirm that the electromagnetic stress testing method is feasible and valid.
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机译：metodi microbiologici Tradizionali e metodi moleculeolari per l'analisi degli integratori alimentari a base di o con probiotici per ujso umano（microbiological and molecular methods for analysis of probiotic Based Food supplements for Human Consumption）。
机译：Geukgong space micro seconds (超 Mikro 空间 隙 孔) using a silica-based optical aggregate building materials (Silica 系 矿 骨材) (建材) and its manufacturing method with
