Motor Fault Diagnosis Based on Short-time Fourier Transform and Convolutional Neural Network

With the rapid development of mechanical equipment, the mechanical health monitoring field has entered the era of big data. However, the method of manual feature extraction has the disadvantages of low efficiency and poor accuracy, when handling big data. In this study, the research object was the asynchronous motor in the drivetrain diagnostics simulator system. The vibration signals of different fault motors were collected. The raw signal was pretreated using short time Fourier transform （STFT） to obtain the corresponding time-frequency map. Then, the feature of the time-frequency map was adap- tively extracted by using a convolutional neural network （CNN）. The effects of the pretreatment method, and the hyper parameters of network diagnostic accuracy, were investigated experimentally. The experimental results showed that the influence of the preprocessing method is small, and that the batch-size is the main factor affecting accuracy and training efficiency. By investigating feature visualization, it was shown that, in the case of big data, the extracted CNN features can represent complex mapping relationships between signal and health status, and can also overcome the prior knowledge and engineering experience requirement for feature extraction, which is used by tra- ditional diagnosis methods. This paper proposes a new method, based on STFT and CNN, which can complete motor fault diagnosis tasks more intelligently and accurately.

Intervention of Peiyuan Huayu Decoction on the neuron damage in model rats with acute subdural hematoma

Objective:To study the intervention effect of Peiyuan Huayu Decoction on the neuron damage in model rats with acute subdural hematoma (ASDH).Methods: 160 SD rats were randomly divided into four groups, and the ASDH model rats were made by stereotactic autoblood injection, and sham operation group received craniotomy without blood injection. Sham operation group and model group were normally bred after model establishment, and 6 h after model establishment, the treatment group received intragastric administration of Peiyuan Huayu Decoction, and control group received intragastric administration of Piracetam Tablets, 1 time a day. On the 1d, 3d, 5d and 7d after model establishment, the general conditions of rats (activity, food intake and mental state) were observed, blood was collected via auricula dextra, ELISA method was used to determine peripheral plasma NSE and S100β protein contents, routine HE staining was conducted after perfusion fixation, the neurons in blood injection side of brain tissue were counted, and the neuron damage was observed.Results: 26 rats were dead in the experiment. The general conditions of sham operation group were significantly better than those of other groups, treatment group was significantly better than model group and control group on the 5d group (P<0.05), and there was no significant difference on the 1d, 3d and 7d (P>0.05);neuron count of sham operation group was basically stable, treatment group was not different from model group and control group on the 1d (P>0.05), treatment group was better than model group (P<0.05), and not different from control group (P>0.05) on the 3d, and treatment group was better than model group and control group on the 5d and 7d (P<0.05);peripheral plasma S100β protein and NSE contents of sham operation group were at lower levels, treatment group was not significantly different from model group and control group on the 1d (P>0.05), S100β protein and NSE contents decreased significantly on the 3d, and treatment group was significantly different from model group and control group (P<0.05), S100β protein and NSE contents increased on the 5d and 7d, the increase in treatment group was slower than that in model group and control group, and there was significant difference (P<0.05).Conclusion:Peiyuan Huayu Decoction has obvious protective effect on the neurons in ASDH model rats, and this effect may be based on the inhibition of secondary neuron damage.

Reduced delay in diagnosis of odontogenic keratocysts with malignant transformation:A case report

BACKGROUND In rare cases,odontogenic keratocysts(ODs)transform into squamous cell carcinoma.Intervals between the first attendance of a patient and the diagnosis of OD with malignant transformation vary from weeks to years.In this article,we report a case of malignancy derived from OD with a five-day delay in diagnosis.CASE SUMMARY A 54-year-old woman was referred to Tongji Hospital in Wuhan,China with complaints of moderate pain,recurrent swelling,and pus discharge around her left maxillary lateral incisor for over 10 years.Physical examination revealed a fistula at the palatine-side mucoperiosteum of the left maxillary lateral incisor and enlarged lymph node in the left neck.Cone beam computed tomography revealed a cystic lesion with massive bone destruction from the left maxillary central incisor to the left secondary maxillary premolar and local bony destruction in the left first mandibular molar.The patient was clinically diagnosed with OD.Enucleation rather than marsupialization was performed given the risk factors of long history,recent aggravated pain,and massive bony destruction.Malignant transformation of OD was confirmed by pathologists 3 d after the operation.Radical surgery was performed,and lymph node metastasis was observed.The patient was subjected to postoperative radiotherapy and synchronous chemotherapy,and no local recurrence or distant metastasis was noted at one-year follow-up.CONCLUSION Our case suggests that clinicians should be aware of the malignant transformation of OD,especially when patients present with a long history,massive cyst,chronic inflammation,recent persistent infections,aggravated pain,numbness around the cystic lesion,and lymph node enlargement.

Correlation of MMP-2 gene polymorphism with disease relapse as well as inflammatory mediators and oxidative stress molecules in patients with ischemic stroke

Objective:To study the correlation of MMP-2 gene polymorphism with disease relapse as well as inflammatory mediators and oxidative stress molecules in patients with ischemic stroke. Methods: Patients with primary and recurrent ischemic stroke who were treated in Shaanxi Provincial People's Hospital between January 2015 and December 2016 were selected as the primary group and recurrent group respectively;healthy volunteers who received physical examination during the same period were selected as control group. Serum MMP-2 gene polymorphism and inflammatory mediator levels as well as peripheral blood oxidative stress molecule expression were determined.Results: Serum MMP2 gene 735 loci CC genotype constituent ratio of recurrent group was significantly higher than that of control group and primary group while CT genotype and TT genotype constituent ratio were significantly lower than those of control group and primary group;serum HMBG1, FKN, TNF-α, IL-1β and IL-17 levels as well as peripheral blood Keap1 mRNA expression in stoke patients with MMP2 gene CC genotype were significantly higher than those in stoke patients with MMP2 gene CT genotype and MMP2 gene TT genotype while peripheral blood Nrf2, ARE, NQO1 and HO1 mRNA expression were significantly lower than those in stoke patients with MMP2 gene CT genotype and MMP2 gene TT genotype.Conclusions:MMP-2 gene CC genotype in patients with ischemic stroke can aggravate inflammatory response and oxidative stress response, and is closely related to disease relapse.

Relationship of Nogo-A gene expression in serum and cerebrospinal fluid with nerve injury and inflammatory factor levels in patients with craniocerebral trauma

Objective:To study the relationship of Nogo-A gene expression in serum and cerebrospinal fluid with nerve injury and inflammatory factor levels in patients with craniocerebral trauma. Methods:82 patients with craniocerebral trauma who were treated in our hospital between January 2015 and February 2017 were collected as observation group, and 58 normal subjects who received internal hemorrhoids surgery under lumbar anesthesia in our hospital during the same period were collected as control group. Fluorescence quantitative PCR method was used to detect Nogo-A gene expression in serum and cerebrospinal fluid of both groups, and enzyme-linked immunosorbent assay (ELISA) was used to determine serum levels of nerve injury indexes and inflammatory factors in two groups. Pearson test was used to assess the relationship of Nogo-A gene expression in serum and cerebrospinal fluid with disease severity in patients with craniocerebral trauma.Results: Nogo-A mRNA expression in the serum and cerebrospinal fluid of observation group were higher than those of the control group;serum IGF-Ⅱ level was lower than that of control group while NSE, MBP and S100B levels were higher than those of control group;serum HSP-70, PCT, IL-1β, IL-6 and CRP levels were higher than those of control group. Pearson test showed that Nogo-A gene expression in serum and cerebrospinal fluid of patients with craniocerebral trauma were directly correlated with the nerve injury degree and inflammatory factor levels.Conclusions: Nogo-A gene is highly expressed in patients with craniocerebral trauma, and its expression is directly correlated with the nerve injury and systemic inflammatory response.