Intelligent Bearing Fault Diagnosis Method Combining Mixed Input and Hybrid CNN-MLP model

Rolling bearings are one of the most widely used bearings in industrial machines. Deterioration in the condition of rolling bearings can result in the total failure of rotating machinery. AI-based methods are widely applied in the diagnosis of rolling bearings. Hybrid NN-based methods have been shown to achieve the best diagnosis results. Typically, raw data is generated from accelerometers mounted on the machine housing. However, the diagnostic utility of each signal is highly dependent on the location of the corresponding accelerometer. This paper proposes a novel hybrid CNN-MLP model-based diagnostic method which combines mixed input to perform rolling bearing diagnostics. The method successfully detects and localizes bearing defects using acceleration data from a shaft-mounted wireless acceleration sensor. The experimental results show that the hybrid model is superior to the CNN and MLP models operating separately, and can deliver a high detection accuracy of 99,6% for the bearing faults compared to 98% for CNN and 81% for MLP models

Валентин Евгеньевич Синицын – редактор раздела

.

Surface Tension and Density of Fe–Mn Melts

Abstract: The article presents original experimental data on surface tension of the Fe100 – xMnx (x = 4–13 wt %) melts. Surface tension and density of the melt were measured by the sessile drop method at heating from the liquidus temperature to 1780°C and subsequent sample cooling in the atmosphere of high-purity helium. Temperature and concentration dependences of surface tension and density of Fe–Mn melts were plotted. Manganese is a surface-active substance in iron melt. The value of surface tension coefficient of Fe–Mn melts decreases as Mn content increases. Experimental data on the surface tension of Fe–Mn melts is consistent with the theoretical dependences (the Pavlov–Popel’ equation and the Shishkovsky equation). During the investigation of Fe–Mn melt microheterogenity, correlation between the values of kinematic viscosity, surface tension, and density is revealed. Fluidity dependence of Fe–Mn melts on their density in the cooling mode has a linear character which indicates satisfaction of the Bachinskii law. Discrepancy in the melt viscosity ratios to the surface tension coefficient obtained from the experimental data and from the empirical formula is discovered. Using the experimental data on viscosity and surface tension of Fe–Mn melts, the entropy change in the melt’s bulk and the change in the melt’s surface entropy, respectively, are studied. The surface entropy and the bulk entropy in the melt decrease in their absolute value with its increasing Mn content. From the study results, it is concluded that there is no destruction of the microheterogeneous structure of Fe100 – xMnx (x = 4–13 wt %) melts when heated up to 1780°C. © 2020, Allerton Press, Inc.The reported study was funded by Russian Foundation for Basic Research, project no. 19-33-90198

Near-seismic effects in ULF fields and seismo-acoustic emission: statistics and explanation

International audiencePreseismic intensification of fracturing has been investigated from occurrence analysis of seismo-acoustic pulses (SA foreshocks) and ULF magnetic pulses (ULF foreshocks) observed in Karimshino station in addition to seismic foreshocks. Such analysis is produced for about 40 rather strong and nearby isolated earthquakes during 2 years of recording. It is found that occurrence rate of SA foreshocks increases in the interval (-12, 0 h) before main shock with 3-times exceeding of background level in the interval (-6, -3 h), and occurrence probability of SA foreshocks (pA~75%) is higher than probability of seismic foreshocks (ps~30%) in the same time interval.ULF foreshocks are masked by regular ULF activity at local morning and daytime, nevertheless we have discovered an essential ULF intensity increase in the interval (-3, +1 h) at the frequency range 0.05-0.3 Hz. Estimated occurrence probability of ULF foreshocks is about 40%. After theoretical consideration we conclude: 1) Taking into account the number rate of SA foreshocks, their amplitude and frequency range, they emit due to opening of fractures with size of L=70-200 m (M=1-2); 2) The electro-kinetic effect is the most promising mechanism of ULF foreshocks, but it is efficient only if two special conditions are fulfilled: a) origin of fractures near fluid-saturated places or liquid reservoirs (aquifers); b) appearance of open porosity or initiation of percolation instability; 3) Both SA and ULF magnetic field pulses are related to near-distant fractures (r<20-30 km); 4) Taking into account number rate and activation period of seismic, SA and ULF foreshocks, it is rather probable that opening of fractures and rupture of fluid reservoirs occur in the large preparation area with horizontal size about 100-200km

Study of structure-property relationship in steels based on analysis of EBSD data

In this work, we formulate novel data-driven assays for exploring the structure-property linkages for high-manganese austenitic wear-resistant steel 110G13L (Hadfield steel). Steel 110G13L has the following chemical composition, wt.%: C(0.95-1.50)-Mn(11.5-15.0). These assays are built on recent advances in high resolution quantification of material structure using correlations and principal analyses of electron backscatter diffraction (EBSD) data, as well as in the mechanical characterization using nanoindentation. These novel protocols are demonstrated on a steel 110G13L that exhibits various polycrystalline microstructures. A comparative analysis of EBSD data was carried out for samples of manganese steel 110G13L obtained by various methods. Analysis of the diffraction patterns of backscattered electrons allowed us to plot orientation maps, Schmid factor maps and distributions for austenite dendrites. Schmid factor maps are used to determine the degree of homogeneity of a possible deformation. The results of the measurement of hardness and Young's modulus for the austenite dendrites indicate the heterogeneity of the mechanical properties of the material in submicro-volumes due to lattice defects (dislocations) inside the crystallites. © Published under licence by IOP Publishing Ltd.Russian Foundation for Basic Research, RFBR: 19-33-90198The equipment of the Ural Centre for Shared Use “Modern nanotechnology” UrFU was used. The reported study was funded by RFBR (project No. 19-33-90198)

Complementary improvement of technological characteristics of asphalt concrete road surfaces using macromolecular nanocomposites

ABSTRACT: Introduction. The issue of enhancing the long-term performance of asphalt concrete pavement on highways is not entirely addressed by conventional solutions, such as improving the choice of material composition and refining the production process for bitumen binders and mineral filler compounds. One of the most promising ways to improve the performance and durability of asphalt concrete is the complementary modification of bitumen and road-concrete nanocompositions with thermoplastic and elastic polymers. Methods and materials. Bitumen binders are assessed employing suitable methodologies to determine the following technological parameters: extensibility, softening temperature, brittleness, elasticity, and so forth. Asphaltenes of bitumen binders are the most important structure-forming component and form associated nanoclusters with sizes of 15–200 nm. Thermoplastic block copolymers are introduced into the composition of bitumen binders in granular form (chips) or melted form. Additionally, compatibilizers are used to improve the compatibility of complementary copolymers in bitumen binders. The quality of the finished asphalt concrete composition is significantly affected by the characteristics of the main components: mineral powder, sand, crushed stone, bitumen binder and macromolecular nano-additives, as well as by optimal process modes: mixing temperature, etc. Results. The complementary interaction of supramolecular associations of asphaltenes and fragments of macromolecules of polymer nanocomposites ensures the formation of Van der Waals bonds due to spatial mutual correspondence. The introduction of polymer nanomodifiers leads to an increase in the softening temperature and a decrease in the brittleness temperature of bitumen binders due to the formation of sufficiently stable supramolecular complexes. Discussion. Synergistic nanoadditives of complementary macromolecules into the bitumen binder provides a fewfold increase in the adhesion of the bitumen composition and the mineral components, as well as a noticeable increase of the temperature range for plasticity and deformability. Asphalt concrete coatings with polymer-bitumen binders increase the operability of the roadway and resistance to the formation of plastic flow deformations (shifts, ruts) at high and low temperatures. Conclusion. Bitumen binders of asphalt road concrete, which have been modified with polymer nanocomposites, have higher adhesion, an extended range of thermoplasticity and water resistanc

About possibility to locate an EQ epicenter using parameters of ELF/ULF preseismic emission

A relation between parameters of preseismic ULF/ELF emissions and EQ is studied. The magnetic data measured at Karymshino station (Kamchatka, Russia) along with data on local seismic activity during eight years of observations (2001–2008) are taken for the analysis. Source azimuth is detected in different techniques, based on the analysis of the total field and its polarized pulsed component. The latter technique shows a better accuracy in the source azimuth detection. The errors of the method are associated with existence of non-seismic sources and with use of one-point observation. The second error can be eliminated by development of multi-point observations

Оценка возможности применения позитронно-эмиссионной компьютерной томографии с применением 18F-фтордезоксиглюкозы у пациентов с метастазами из невыявленного первичного очага в области головы и шеи

Introduction. Cancer metastases from an unknown primary origin (CUP) in the head and neck area include a large heterogeneous group of tumor formations, the primary localization of which could not be established even after a thorough diagnostic search. Combined positron emission computed tomography (PET-CT) with 18F-FDG has a high level of detection of primary neoplasms as a result of simultaneous acquisition of precisely combined anatomical and functional images of the entire body.Objectives. 1. To evaluate the possibility of using PET-CT (positron emission tomography in combination with computed tomography) with 18F-FDG (18-fluorodeoxyglucose) in patients with metastases from the CUP (carcinoma unknown primary) in the head and neck.2. To determine the effectiveness of PET-CT for the detection of primary tumor focus in patients with histologically verified diagnosis of CUP in the head and neck.3. To evaluate the contribution of the PET-CT technique in assessing the prevalence of the disease in patients diagnosed with head and neck cancer.Materials and methods. 134 patients diagnosed with CUP in the head and neck from September 2018 to March 2019 were included to this retrospective study: 35(26.1%) women and 99(73.9%) men, with the mean age of 61.9 ± 7.5 years. All patients underwent a biopsy from at least one metastatic lesion, and the malignant nature of the neoplasm was histologically verified. Before PET-CT with 18F-FDG, standard oncological evaluation was carried out to detect primary tumor.Results. Among 134 patients comprised the study, initial histological diagnoses were: squamous cell cancer (n = 82, 61.2%), melanoma (n = 5, 3.7%), undifferentiated carcinoma (n = 20, 15%), adenocarcinoma (n = 21, 15.6%) and undifferentiated malignant neoplasm (n = 6, 4.5%).With PET-CT with 18F-FDG, primary tumor location was revealed in 72 (54%) of the patients. New metastatic lesions were found in 60 (44.7%) of the patients.Change in the TNM stage was observed in 95(71%) of all cases after PET-CT with 18F-FDG. It was associated both with the detection of the primary tumor and the identification of new metastatic foci.Conclusions. Use of PET-CT with 18F-FDG allows to carry out oncological evaluation more precisely than the standard procedures in the majority of patients with CUP in the head and neck region. In a significant quota of cases, this method is in a position also to help to identify the primary tumor lesion, which, in turn, influences on strategy of treatment and also on the prognosis of disease. PET-CT with 18F-FDG should be included to the protocol of radiological examination in patients with CUP in the head and neck anatomic area.Введение. Метастазы рака из невыявленного первичного очага (НПО) в области головы и шеи включают большую гетерогенную группу опухолевых образований, первичную локализацию которых не удалось установить даже после тщательного диагностического поиска. Позитронно-эмиссионная томография в сочетании с компьютерной томографией с 18-фтордезоксиглюкозой (ПЭТ-КТ с 18F-ФДГ) имеет высокий уровень обнаружения первичных новообразований в результате одновременного получения точно совмещенных анатомических и функциональных изображений всего тела.Задачи исследования. Оценить возможность применения ПЭТ-КТ с 18F-ФДГ у пациентов с метастазами из НПО в области головы и шеи.1. Определить эффективность ПЭТ-КТ для обнаружения первичного опухолевого очага у пациентов с гистологически верифицированным диагнозом НПО в области головы и шеи.2. Оценить вклад методики ПЭТ-КТ в оценку распространенности заболевания у пациентов с диагнозом НПО в области головы и шеи.Материал и методы. За период с сентября 2018 г. по март 2019 г. в ретроспективное исследование было включено в общей сложности 134 пациента с диагнозом метастазов рака из НПО в области головы и шеи: 35 (26,1%) из них женщины и 99 (73,9%) – мужчины. Средний возраст пациентов, включенных в исследование, составил 61,9 ± 7,5 года. Всем пациентам перед ПЭТ-КТ была проведена пункционная биопсия как минимум одного метастатического очага и гистологически верифицирован злокачественный характер новообразования, а также был проведен ряд стандартных исследований в рамках онкопоиска для выявления природы первичного опухолевого очага.Результаты. Среди 134 пациентов, включенных в исследование, наблюдалось следующее распределение гистологических вариантов опухоли (по данным биопсии метастатических лимфатических узлов): 82 (61,2%) пациента с диагнозом плоскоклеточного рака, 5 (3,7%) пациентов с диагнозом меланомы, 20 (15%) пациентов с недифференцированной карциномой, 21 (15,6%) пациент с аденокарциномой и 6 (4,5%) пациентов с недифференцированным злокачественным новообразованием.В ходе исследования первичную локализацию опухоли удалось установить у 72 (54%) пациентов, у 62 (46%) оставшихся пациентов первичный источник не был обнаружен. Возраст пациентов в группах с выявленным и не выявленным первичным очагом после проведения ПЭТ-КТ достоверно не отличался.Новые, не выявленные ранее метастатические очаги были обнаружены при проведении ПЭТ-КТ у 60 пациентов, что составило 44,7% от всей выборки. Стоит отметить, что изменение в оценке распространенности опухолевого процесса после проведения ПЭТ-КТ произошло в 95 (71%) случаях, что было связано как с обнаружением первичной опухоли, так и с выявлением новых метастатических очагов.Выводы. Применение ПЭТ-КТ позволяет точнее определить стадию онкологического процесса у значительной части пациентов с НПО в области головы и шеи. В значительной части случаев метод позволяет выявить первичную опухоль, что, в свою очередь, оказывает влияние на тактику лечения и прогноз у данных пациентов. Применение ПЭТ-КТ должно обязательно включаться в план обследования пациентов с метастазами рака из НПО в области головы и шеи

Study of electromagnetic emissions associated with seismic activity in Kamchatka region

International audienceA review of data processing of electromagnetic emission observation collected at the Complex Geophysical Observatory Karimshino (Kamchatka peninsula) during the first 5 months (July?November, 2000) of its operation is given. The main goal of this study addresses the detection of the phenomena associated with Kamchatka seismic activity. The following observations have been conducted at CGO: variations of ULF/ELF magnetic field, geoelectric potentials (telluric currents), and VLF signals from navigation radio transmitters. The methods of data processing of these observations are discussed. The examples of the first experimental results are presented