Reliability Evaluation for the Running State of the Manufacturing System Based on Poor Information

The output performance of the manufacturing system has a direct impact on the mechanical product quality. For guaranteeing product quality and production cost, many firms try to research the crucial issues on reliability of the manufacturing system with small sample data, to evaluate whether the manufacturing system is capable or not. The existing reliability methods depend on a known probability distribution or vast test data. However, the population performances of complex systems become uncertain as processing time; namely, their probability distributions are unknown, if the existing methods are still taken into account; it is ineffective. This paper proposes a novel evaluation method based on poor information to settle the problems of reliability of the running state of a manufacturing system under the condition of small sample sizes with a known or unknown probability distribution. Via grey bootstrap method, maximum entropy principle, and Poisson process, the experimental investigation on reliability evaluation for the running state of the manufacturing system shows that, under the best confidence level P=0.95, if the reliability degree of achieving running quality is r>0.65, the intersection area between the inspection data and the intrinsic data is A(T)>0.3 and the variation probability of the inspection data is PB(T)≤0.7, and the running state of the manufacturing system is reliable; otherwise, it is not reliable. And the sensitivity analysis regarding the size of the samples can show that the size of the samples has no effect on the evaluation results obtained by the evaluation method. The evaluation method proposed provides the scientific decision and suggestion for judging the running state of the manufacturing system reasonably, which is efficient, profitable, and organized

Properties of a Steel Slag–Permeable Asphalt Mixture and the Reaction of the Steel Slag–Asphalt Interface

Steel slag is an industrial solid waste with the largest output in the world. It has the characteristics of wear resistance, good particle shape, large porosity, etc. At the same time, it has good adhesion characteristics with asphalt. If steel slag is used in asphalt pavement, it not only solves the problem of insufficient quality aggregates in asphalt concrete, but can also give full play to the high hardness and high wear resistance of steel slag to improve the performance of asphalt pavement. In this study, a steel slag aggregate was mixed with road petroleum asphalt to prepare a permeable steel slag–asphalt mixture, which was then compared with the permeable limestone–asphalt mixture. According to the Technical Regulations for Permeable Asphalt Pavement (CJJT 190-2012), the permeability, water stability, and Marshall stability of the prepared asphalt mixtures were tested and analyzed. In addition, the high-temperature stability and expansibility were analyzed according to the Experimental Regulations for Highway Engineering Asphalt and Asphalt Mixture (JTG E20-2011). The chemical composition of the steel slag was tested and analyzed by X-ray fluorescence spectrometer (XRF). The mineral composition of the steel slag was tested and analyzed by X-ray diffractometer (XRD). The asphalt was analyzed by Fourier transform infrared spectroscopy (FTIR). The results show that the steel slag asphalt permeable mixture had good permeability, water stability, and Marshall stability, as well as good high-temperature stability and a low expansion rate. The main mineral composition was ferroferric oxide, the RO phase (RO phase is a broad solid solution formed by melting FeO, MgO, and other divalent metal oxides such as MnO), dicalcium silicate, and tricalcium silicate. In the main chemical composition of steel slag, there was no chemical reaction between aluminum oxide, calcium oxide, silicon dioxide, and asphalt, while ferric oxide chemically reacted with asphalt and formed new organosilicon compounds. The main mineral composition of the steel slag (i.e., triiron tetroxide, dicalcium silicate, and tricalcium silicate) reacted chemically with the asphalt and produced new substances. There was no chemical reaction between the RO phase and asphalt

Prediction of Manufacturing System Using Improved Infomax Method Based on Poor Information

The improved infomax method consists of the bootstrap methodology, the grey system theory, and the information entropy theory. The bootstrap methodology is adopted to imitate the generated information vector of large size by bootstrap resampling from the current information vector of small size, the grey system theory is used to introduce the generated information vector into the grey prediction model for forecasting the future information vector of large size, and the information entropy theory is employed to predict a probability distribution of the future information via the maximum entropy criterion. Information prediction of a manufacturing system is put into practice under the condition of poor information. Case studies of the diameter and roundness of a tapered rolling bearing raceway present that the method is able to make reliably information prediction of a manufacturing system only with the current information of small size and without any prior information of probability distributions

Fuzzy Norm Method for Evaluation of Uncertainty in Vibration Performance of Rolling Bearing

With the rapid development of science and technology, the performance of current bearings in terms of variations in friction, wear, vibration, temperature rise, etc. is drawing considerable attention. The limited availability of characterization data and a lack of a priori knowledge concerning the probability distribution and trends in bearing performance have rendered it difficult to perform a statistical analysis on this topic. To overcome these limitations, in this paper, we adopt the fuzzy norm method, which integrates fuzzy theory with the norm method. We utilize the fuzzy norm method to assess the uncertainty in rolling bearing vibration performance, which can help to reveal the degree of variation in rolling bearing vibration performance despite the unknown probability distribution and trends, thereby allowing for accurate assessment of the vibration conditions of bearings. The results of an experimental investigation of a specific type of rolling bearing vibration-acceleration time series demonstrate the correctness and effectiveness of the proposed method

Video Super-Resolution Using Multi-Scale and Non-Local Feature Fusion

Video super-resolution can generate corresponding to high-resolution video frames from a plurality of low-resolution video frames which have rich details and temporally consistency. Most current methods use two-level structure to reconstruct video frames by combining optical flow network and super-resolution network, but this process does not deeply mine the effective information contained in video frames. Therefore, we propose a video super-resolution method that combines non-local features and multi-scale features to extract more in-depth effective information contained in video frames. Our method obtains long-distance effective information by calculating the similarity between any two pixels in the video frame through the non-local module, extracts the local information covered by different scale convolution cores through the multi-scale feature fusion module, and fully fuses feature information using different connection modes of convolution cores. Experiments on different data sets show that the proposed method is superior to the existing methods in quality and quantity

减重手术的减重和代谢获益:一项中国多中心研究

Abstract Background This retrospective multicenter study evaluated the efficacy and safety of bariatric surgery in Chinese patients with obesity. Methods Patients with obesity who underwent laparoscopic sleeve gastrectomy or laparoscopic Roux‐en‐Y gastric bypass and completed a 12‐month follow‐up between February 2011 and November 2019 were enrolled. Weight loss, glycemic and metabolic control, insulin resistance, cardiovascular risk, and surgery‐related complications at 12 months were analyzed. Results We enrolled 356 patients aged 34.3 ± 0.6 years with a mean body mass index of 39.4 ± 0.4 kg/m2. Successful weight loss occurred in 54.6%, 86.8%, and 92.7% of patients at 3, 6, and 12 months, respectively, with no difference in percent excess weight loss between the laparoscopic sleeve gastrectomy and laparoscopic Roux‐en‐Y gastric bypass surgery groups. The average percentage of total weight loss was 29.5% ± 0.6% at 12 months; 99.4%, 86.8%, and 43.5% of patients achieved at least 10%, 20%, and 30% weight loss, respectively, at 12 months. Significant improvements in metabolic indices, insulin resistance, and inflammation biomarkers were observed at 12 months. Conclusions Bariatric surgery resulted in successful weight loss and improved metabolic control, insulin resistance, and cardiovascular risk in Chinese patients with obesity. Both laparoscopic sleeve gastrectomy and laparoscopic Roux‐en‐Y gastric bypass are suitable approaches for such patients

Influence of temperature, pressure, and fluid salinity on the distribution of chlorine into serpentine minerals

Serpentinization produces serpentine minerals that have abundant water and fluid-mobile elements (e.g., Ba, Cs, and Cl). The dehydration of serpentine minerals produced chlorine-rich fluids that may be linked with the genesis of arc magmas. However, the factors that control the distribution of chlorine into serpentine minerals remain poorly constrained. We performed serpentinization experiments at 80-500 degrees C and pressures from vapor saturated pressures to 20 kbar on peridotite, orthopyroxene, and olivine with < 5% pyroxene. The results show that the concentrations of chlorine in serpentine minerals were up to 1.2 wt% at 200 degrees C, whereas they decreased slightly at 311-400 degrees C and 3.0 kbar and became significantly lower at 485 degrees C and 3.0 kbar, similar to 0.1 wt%. Fluid salinity greatly decreased chlorine concentrations of olivine-derived serpentine produced at 400 degrees C and 3.0 kbar, which was associated with a decrease in silica mobility during serpentinization. By contrast, influence of fluid salinity at 311 degrees C and 3.0 kbar is minor. Moreover, chlorine distribution into serpentine can be influenced by primary minerals of serpentine. Serpentine formed in olivine-only experiments at 311 degrees C and 3.0 kbar had 0.08 +/- 0.03 wt% Cl, which is significantly lower than chlorine concentrations of serpentine minerals (0.49 +/- 0.36 wt%) produced in orthopyroxene-only experiments. By contrast, for experiments at 311 degrees C and 3.0 kbar, olivine- and orthopyroxene-derived serpentine had comparable amounts of chlorine. In particular, olivine-derived serpentine had 0.16 +/- 0.09 wt% Cl that was slightly higher than chlorine concentrations of serpentine formed in olivine-only experiments, whereas orthopyroxene-derived serpentine had significantly lower chlorine concentrations than that formed in orthopyroxene-only experiments. The contrast may be associated with releases of aluminum and silica from pyroxene minerals, which possibly results in a decrease in chlorine concentrations of serpentine. The concentrations of chlorine in serpentine formed in experiments at 311 degrees C and 3.0 kbar were slightly lower than those in serpentine produced at 300 degrees C and 8.0 kbar, which may be associated with influence of pressure on the mobility of iron and silica. The experimental results of this study indicate that serpentine minerals are important carriers of chlorine in subduction zones. It also suggests that chlorine is significant for the redistribution of cations during serpentinization

Influence of pyroxene and spinel on the kinetics of peridotite serpentinization

Hydrothermal experiments were performed at 311 degrees C and 3.0 kbar on natural olivine and peridotite to investigate the kinetics of serpentinization. The results show that the rates of reaction strongly depend on grain sizes of solid reactants, with smaller grain sizes resulting in faster kinetics. After 27 days of reaction, the reaction extent was 99% for peridotite with grain sizes of <30 mu m, and the reaction extent was 28% for grain sizes of 100-177 mu m. Compared to peridotite, olivine is serpentinized at much slower rates, e.g., 5.3% of reaction extent was achieved for olivine with grain sizes of 100-177 mu m after 27 days, approximately five times lower than that reached during peridotite serpentinization. Such contrasting results are due to the presence of pyroxene and spinel, an interpretation which is supported by a marked increase in reaction extents for experiments with the addition of pyroxene and spinel. The reaction extent achieved in experiments with 3 wt% spinel greatly increased to 98% after 27 days, much higher than that achieved during olivine serpentinization. These results appear to be related to pyroxene and spinel releasing Al and Cr during serpentinization. As indicated by compositions of serpentine, orthopyroxene lost similar to 60% of Al at a reaction extent of 59%. Influence of Al and Cr is suggested by a dramatic increase in reaction extents with the addition of Al2O3 and Cr2O3 powders. Olivine in natural geological settings is commonly associated with pyroxene and spinel; consequently, serpentinization kinetics may be much faster than previously thought

The production of iron oxide during peridotite serpentinization: Influence of pyroxene

Serpentinization produces molecular hydrogen (H2) that can support communities of microorganisms in hydrothermal fields; H2 results from the oxidation of ferrous iron in olivine and pyroxene into ferric iron, and consequently iron oxide (magnetite or hematite) forms. However, the mechanisms that control H2 and iron oxide formation are poorly constrained. In this study, we performed serpentinization experiments at 311 °C and 3.0 kbar on olivine (with <5% pyroxene), orthopyroxene, and peridotite. The results show that serpentine and iron oxide formed when olivine and orthopyroxene individually reacted with a saline starting solution. Olivine-derived serpentine had a significantly lower FeO content (6.57 ± 1.30 wt.%) than primary olivine (9.86 wt.%), whereas orthopyroxene-derived serpentine had a comparable FeO content (6.26 ± 0.58 wt.%) to that of primary orthopyroxene (6.24 wt.%). In experiments on peridotite, olivine was replaced by serpentine and iron oxide. However, pyroxene transformed solely to serpentine. After 20 days, olivine-derived serpentine had a FeO content of 8.18 ± 1.56 wt.%, which was significantly higher than that of serpentine produced in olivine-only experiments. By contrast, serpentine after orthopyroxene had a slightly higher FeO content (6.53 ± 1.01 wt.%) than primary orthopyroxene. Clinopyroxene-derived serpentine contained a significantly higher FeO content than its parent mineral. After 120 days, the FeO content of olivine-derived serpentine decreased significantly (5.71 ± 0.35 wt.%), whereas the FeO content of orthopyroxene-derived serpentine increased (6.85 ± 0.63 wt.%) over the same period. This suggests that iron oxide preferentially formed after olivine serpentinization. Pyroxene in peridotite gained some Fe from olivine during the serpentinization process, which may have led to a decrease in iron oxide production. The correlation between FeO content and SiO2 or Al2O3 content in olivine- and orthopyroxene-derived serpentine indicates that aluminum and silica greatly control the production of iron oxide. Based on our results and data from natural serpentinites reported by other workers, we propose that aluminum may be more influential at the early stages of peridotite serpentinization when the production of iron oxide is very low, whereas silica may have a greater control on iron oxide production during the late stages instead