Gearbox fault diagnosis based on autocorrelation and HHT

Propose to a method of gearbox fault diagnosis based on autocorrelation and HHT. The method of Empirical mode decomposition (EMD) separate gearbox vibration signal data into several intrinsic mode function (IMF). Through the autocorrelation analysis of each IMF component, which can effectively eliminate the noise component, rapidly and accurately screen out IMF component containing characteristic information of gear fault, and then transform it for Hilbert-Huang, and get the gearbox fault characteristic frequency. After testing real gearbox vibration signals, it shows that the method has higher engineering value

PL - 021 The research of High temperature exercise under different humidity environment effect on the body of water and salt metabolism

Objective Objective: This study was to investigate the body under high temperature (33 ℃) with different relative humidity (80%, 50%, 20%) combination of environment, respectively for 20 min 60% VO2max individual strength of quiet before and after the exposure of movement and under the same conditions, by measuring the participants within the body weight, serum sex hormone of blood, blood Na+、K+, Na+、K+ concentration in the urine of change, to explore in the sports stress and thermal stress of two kinds of stimulating the body water and salt metabolism characteristics, and to explore the effects of environmental humidity on the body's homeostasis. Methods Methods: This study selected 12 students of sports training major from Beijing sports university as subjects, with themselves as the control. The experiment is divided into six categories, respectively: high temperature 33℃ and 20% RH exposure group, the high temperature 33℃ and 20% RH campaign group, high temperature 33℃and 50% RH exposure group, the high temperature 33℃ and 50% RH campaign group, high temperature 33℃ and 80% RH exposure group and high temperature 33℃ and 80% RH. In this study all the environmental temperature are set up to 33℃, exercise intensity level of 60% VO2max selection for individual participants. Before every experiment, all participants were asked to quiet sit for 20 min and then measure the subjects' body weight, charge the subjects' vein blood and urine, take the same operation immediately after the experiment. Blood samples were stored at room temperature for 1 h, and 3000r/min was centrifuged for 20min. Serums were gathered through centrifugation, The urine and Serums were partial shipments in tube to be indicators of measurement. Serum Renin、ANGII、ALD、ADH、ANP、Na+、K+ concentration of serum and urine were tested Results Results:  (1)The subjects' weight loss percentage of exercise group was obviously higher than that of quiet exposure group, the difference is statistically significant (P < 0.01); In 80% RH environment weight loss percentage is significantly higher than that of 50% RH and 20% RH values (P < 0.01).There is no difference between 20%RH and 50%RH. (2) The exercise group of Renin, ANGII, ALD, ADH, concentration is significantly higher than the value of exposed group (P < 0.01), but the ANP concentrations were significantly lower than pure quiet exposure levels (P < 0.01). Conclusions Conclusions: (1) The body sweat more after exercise than just quiet exposed in high temperature, weight loss phenomenon more obvious; And with the increase of relative humidity environment,  dehydration will more serious. (2) Exercise factors can significantly promote the release of blood Renin, ANGII, ALD, ADH and   inhibit the release of ANP in the blood. By the way of strengthening the absorption process of water and ions, it can maintain the body's balance of water and ions

Application of BP Artificial Neural Network in Preparation of Ni–W Graded Coatings

The internal stress difference between soft-ductile aluminum alloy substrate and hard-brittle Ni–W alloy coating will cause stress concentration, thus leading to the problem of poor bonding force. Herein, this work prepared the Ni–W graded coating on aluminum alloy matrix by the pulse electrodeposition method in order to solve the mechanical mismatch problem between substrate and coatings. More importantly, a backward propagation (BP) neural network was applied to efficiently optimize the pulse electrodeposition process of Ni–W graded coating. The SEM, EDS, XRD, Vickers hardness tester and Weighing scales are used to analyze the micromorphology, chemical element, phase composition, and micro hardness as well as oxidation weight increase, respectively. The results show that the optimal process conditions with BP neural network are as follows: the bath temperature is 30 °C, current density is 15 mA/cm2 and duty cycle is 0.3. The predicted value of the model agrees well with the experimental value curve, the relative error is minor. The maximum error is less than 3%, and the correlation coefficient is 0.9996. The Ni–W graded coating prepared by BP neural network shows good bonding with the substrate which has flat and smooth interface. The thickness of the coating is about 136 μm, which slows down the oxidation of the substrate and plays an effective role in protecting the substrate

Mineralogical Characteristics of Exsolved Spinel in the Panzhihua V-Ti Magnetite Deposit, Sichuan: Implications for the Mineralization Process

Spinel exsolution is widespread in titanomagnetite from the Fe-Ti oxide gabbro of the Panzhihua intrusion, Emeishan Large Igneous Province, SW China. However, little research has been conducted into the implications of patterns in the mineralogical characteristics of the spinel for spatial variation in the controls on the exsolution mechanism and, hence, the formation process of the ore deposit. This study selected the Lanjiahuoshan Ore Block in the Panzhihua V-Ti magnetite deposit to explore this issue, systematically studying exsolution textures in the titanomagnetite through petrographic observation and the integrated use of in-situ microanalysis. The results show that the exsolved spinel gradually becomes finer-grained and less abundant from the center to edge and the bottom to top of the ore bodies. Compositionally, there is an inverse correlation between the size of exsolved spinel grains and their Mg# value. In addition, there is compositional zonation in the spinel interiors, with a gradual increase in the Mg content and decrease in Fe content from the core to the rim. The analysis suggests that fractional crystallization of ferrotitanium magma with a high oxygen fugacity in a shallow magma chamber caused compositional differences in the primary magnetite solid solution in different parts of the Panzhihua intrusion. Additionally, the thermal evolution of the magnetite solid solution differed in different parts of orebody, bringing about variations in spinel development. Together, these effects resulted in spatial variation in the abundance, grain size, and morphology of spinel in different parts of the orebody and intrusion that follows an identifiable distribution law. Furthermore, the compositional zonation of exsolved spinels reflects the rapid growth of exsolution features in a high-temperature environment. Thus, the size, morphology, abundance, and composition of spinel exsolution features in titanomagnetite provide a valuable petrogenetic tool for estimating the maturity and formational environment of the deposit

The Genesis of Nano-Micron-Sized Spheroidal Aggregates of FeS2 in the Laozuoshan Gold Deposit, Heilongjiang Province, NE China

Nano-micron-sized spheroidal aggregates of FeS2 has been found from the Laozuoshan gold deposit, Heilongjiang Province, NE China. There are diversified morphology, some as large or small girdles, and some as paragenesis of aggregates through cementation. Most of such aggregates distribute at the edge of pyrrhotite before metasomatized by arsenopyrite. Through a systematic observation on the micro-structure, grain size and components of nano-micron-sized spheroidal aggregates of FeS2 by means of Field Emission Scanning Electron Microscopy (FE-SEM), Electron Probe Micro Analysis (EPMA) and in situ micro X-ray Diffraction (XRD), etc. We found such aggregates are composed of nano-micron-sized grains gathered together, part of which have an euhedral structure, with a crystalline grain size of 50 nm-<1 mu m. The aggregates of FeS2 are composed of pyrite and marcasite, and the crystal face diffraction peak intensities of pyrite (200) and (311) decline remarkably from the center to the edge, and the crystal face diffraction peak intensities of marcasite (110) and (311) in the center are lower than those at the edge. From the center to the edge, the content of Fe in nano-micron-sized spheroidal aggregates changes slightly, but the S content declines remarkably at the edge, and the content of As is low in the center but grows remarkably at the edge. In addition, there are low-temperature minerals such as chalcedony and carbonates (like calcite) filled along the edge of or in the fissures among spheroidal aggregates of FeS2. Based on the above study in combination of the fluid inclusion characteristics of the mineral deposit, we suggest that the spheroidal aggregates of FeS2 are formed under the drive of free energy on the surface of nano-sized FeS2 crystals, which nucleates rapidly in a static fluid environment due to fluid getting supersaturated. The spheroidal aggregates of FeS2 indicate that under low temperature conditions, the pH value of fluid changes from medium acidity to acidity throughout the crystallization process

A comparison of the clinical characteristics of Chinese patients with recurrent major depressive disorder with and without dysthymia☆

BACKGROUND: The relationship between major depressive disorder (MDD) and dysthymia, a form of chronic depression, is complex. The two conditions are highly comorbid and it is unclear whether they are two separate disease entities. We investigated the extent to which patients with dysthymia superimposed on major depression can be distinguished from those with recurrent MDD. METHODS: We examined the clinical features in 1970 Han Chinese women with MDD (DSM-IV) between 30 and 60 years of age across China. Logistic regression was used to determine the association between clinical features of MDD and dysthymia and between dysthymia and disorders comorbid with major depression. RESULTS: The 354 cases with dysthymia had more severe MDD than those without, with more episodes of MDD and greater co-morbidity for anxiety disorders. Patients with dysthymia had higher neuroticism scores and were more likely to have a family history of MDD. They were also more likely to have suffered serious life events. LIMITATIONS: Results were obtained in a clinically ascertained sample of Chinese women and may not generalize to community-acquired samples or to other populations. It is not possible to determine whether the associations represent causal relationships. CONCLUSIONS: The additional diagnosis of dysthymia in Chinese women with recurrent MDD defines a meaningful and potentially important subtype. We conclude that in some circumstances it is possible to distinguish double depression from recurrent MDD