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To solve the problem of determining the fault damage of rolling bearings, a fault diagnosis method for intelligent classification of vibration signals with different fault locations and different damage degrees is proposed. First, the research object is the laboratory dataset. By transforming into spectrograms, this can preserve the original information of the time-domain signal to a greater extent. Then, we use a deep, fully convolutional neural network to train the dataset. It has a rapid convergence and the accuracy is up to 100%. Second, in order to verify the correctness of the model, we take the service data on the real line as the research object, and the accuracy rate is as high as 99.22%. Compared with some other machine learning algorithms, our method boasts better generalization capability and accuracy and could be applied to practical engineering.

Electron paramagnetic resonance (EPR) is used to characterize Pt + (5d 9 ) ions in flux-grown single crystals of KTiOAsO 4 (KTA). These platinum ions are unintentionally present. In the as-grown crystals, Pt 0 (5d 10 ) atoms substitute for K + ions. When a crystal is irradiated with X-rays at room temperature or 77 K, the Pt 0 atoms trap holes and convert to Pt + ions. Once formed, these Pt + ions are stable for weeks at room temperature. The EPR spectrum of the Pt + ions is best observed in the 20–30 K range. Principal values and principal-axis directions for the g matrix and the 195 Pt hyperfine matrix are obtained from EPR angular dependence data taken in three crystal planes. These principal values are 1.509, 1.898, and 2.859 for the g matrix and 96, 317, and 616 MHz for the 195 Pt hyperfine matrix. Formation of the Pt + ions is accompanied by a gray coloration that is expected to affect device performance when KTA crystals are used in high-power nonlinear optical applications. As-grown KTA crystals with larger concentrations of platinum may have lower ionic conductivities, as Pt 0 atoms replace potassium vacancies.

The dominant Ti 3+ trapped electron center in flux-grown RbTiOPO 4 (RTP) crystals has been characterized using electron paramagnetic resonance (EPR) and electron–nuclear double resonance (ENDOR). This center is produced during an X-ray irradiation at room temperature when a Ti 4+ ion traps an electron and becomes a Ti 3+ ion, and is best studied in the 30–40 K range. The EPR spectrum contains a three-line hyperfine pattern from two nearly equivalent neighboring 31 P nuclei, along with hyperfine lines from the 47 Ti and 49 Ti nuclei. The g matrix, determined from the angular dependence of the EPR spectrum, has principal values of 1.819, 1.889, and 1.947. Hyperfine matrices for four 31 P nuclei are obtained from the angular dependence of the ENDOR spectrum. The proposed model for this defect is a Ti 3+ ion adjacent to an oxygen vacancy at an OT position. Analogies are made to a similar Ti 3+ center in KTiOPO 4 (KTP) crystals.

The optical and electrical properties of Co 2+ ions in CdSe have been investigated. Absorption, photoluminescence, electron paramagnetic resonance, and Hall measurements were used to characterize a cobalt-doped (1×10 19 cm −3 ) single crystal. Infrared absorption and emission spectra associated with transitions between the 4 A 2 ( F ) ground state and the 4 T 1 ( F ) and 4 T 2 ( F ) excited states are described. At 10 K, spin–orbit splittings result in three structured absorption bands associated with the 4 A 2 ( F ) to 4 T 1 ( F ) transition having zero-phonon lines at 4926, 5101, and 5724 cm −1 . The 4 A 2 ( F ) to 4 T 2 ( F ) transition shows two zero-phonon lines at 2874 and 3286 cm −1 , also accompanied by vibronic structure. Intrinsic lattice modes explain most of the sharp-line structure observed at low temperature, except for a subset of peaks where local modes (25–30 cm −1 ) are invoked. Using below-band-gap light, selective excitation allows detection of the 4 T 1 ( F ) to 4 A 2 ( F ) recombination at liquid-helium temperatures. The activation of free carriers in our n-type material containing shallow donors is affected by the presence of cobalt, and we find the Co +/++ level to be about 34 meV below the conduction band of CdSe.

Electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) have been used to characterize the complex hyperfine patterns exhibited by the primary radiation-induced trapped hole center in single crystals of RbTiOPO4 (commonly referred to as RTP). These defects are produced at 77 K by irradiating with X-rays, and they are destroyed by raising the temperature above approximately 170 K. In this center, the hole resides on a bridging oxygen ion located between two titanium ions and is stabilized by a nearby rubidium vacancy. Hyperfine splittings from interactions with one rubidium neighbor and one phosphorus neighbor are resolved in the EPR spectra. The ENDOR spectra show one larger phosphorus interaction and four smaller phosphorus interactions. Principal values and principal axis directions for this larger phosphorus interaction are obtained from the ENDOR angular dependence. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Bulk ZnO grown by the hydrothermal technique was investigated using electron paramagnetic resonance (EPR), photoluminescence (PL), and infrared absorption (FTIR) techniques. Isolated subsitutional lithium is the dominant acceptor and could be detected using EPR or PL. A large concentration of neutral Li+-OH− centers were observed using FTIR data. EPR spectra assigned to Mn, Co, Ni, Fe, and Group III (Al, Ga) donors were also observed. Photoinduced changes in the charge states of the different deep and shallow centers were produced using 325 nm light, and the stability of these changes were monitored with EPR during pulsed thermal anneals. The charge-state changes for some defects were persistent and remained up to 300 K. These impurities, when present in device structures, may act as stable charge trapping sites.

Electron paramagnetic resonance (EPR) has been used to monitor photoinduced changes in the charge states of deep transition-metal donors (Mn, Fe, Co, and Ni), shallow donors (Al and Ga), and lithium acceptors in a hydrothermally grown ZnO crystal. All of these impurities except the lithium were unintentionally present. Changes in charge states were photoinduced at low temperature using 325nm light. Before illumination, the transition-metal donors were present in divalent and trivalent charge states, and all the lithium acceptors were in the singly ionized charge state. During illumination, neutral lithium acceptors were formed, the Fe3+, Ni3+, and Mn3+ spectra disappeared (i.e., they converted to divalent states), and the Mn2+ and Co2+ spectra increased. When the light was removed, these changes in charge states were persistent and stable at low temperature. The thermal stabilities of the changes were monitored during a pulsed anneal (the sample was warmed in steps to sequentially higher temperatures and ...