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The rotor misalignment fault, which occurs only second to unbalance, easily occurs in the practical rotating machinery system. Rotor misalignment can be further divided into coupling misalignment and bearing misalignment. However, most of the existing references only analyze the effect of coupling misalignment on the dynamic characteristics of the rotor system, and ignore the change of bearing excitation caused by misalignment. Based on the above limitations, a five degrees of freedom nonlinear restoring force mathematical model is proposed, considering misalignment of bearing rings and clearance of cage pockets. The finite element model of the rotor is established based on the Timoshenko beam element theory. The coupling misalignment excitation force and rotor unbalance force are introduced. Finally, the dynamic model of the ball bearing-coupling-rotor system is established. The radial and axial vibration responses of the system under misalignment fault are analyzed by simulation. The results show that the bearing misalignment significantly influences the dynamic characteristics of the system in the low-speed range, so bearing misalignment should not be ignored in modeling. With the increase of rotating speed, rotor unbalance and coupling misalignment have a greater impact. Misalignment causes periodic changes in bearing contact angle, radial clearance, and ball rotational speed. It also leads to reciprocating impact and collision between the ball and cage. In addition, misalignment increases the critical speed and the axial vibration of the system. The results can provide a basis for health monitoring and misalignment fault diagnosis of the rolling bearing-rotor system.

Analysis of dynamic characteristics of the defective bearing is significant for the fault diagnosis of the machinery. At present, there are few researches on numerical modeling of bearing with defective roller. To solve this problem, explicit finite element method is adopted in this paper to establish a nonlinear dynamic model of the cylindrical roller bearing with roller spalling defects. In the proposed model, the flexibility of all the components, the internal friction, the relative sliding, the finite size of the roller and the rollers-to-cage contact force are all considered. Then the proposed dynamic model is verified theoretically and experimentally. The vibration responses of bearing and the sliding behavior of defective roller and cage are analyzed based on the proposed numerical model. The results show that the roller-to-cage contact force will be increased and the slippage of the defective roller will be aggravated when the roller defect occurs. In addition, the increment of defect width and number of defective rollers will aggravate the vibration of bearing and the sliding of cage.

The development of an energy-efficient fractionation process as well as the preservation of the fractionated cellulose, hemicellulose sugars, and lignin are the key to the valorization of lignocellulose. This study presents a mild-condition fractionation process based on a recyclable and bifunctional 4-chlorobenzenesulfonic acid (4-Cl-BSA). The aqueous (e.g., 72%) 4-Cl-BSA solution near-completely fractionated unmilled poplar chips at 50–80 °C for 18–180 min and successively preserved the theoretical maximum yields and key structures of the fractionated cellulose, lignin, and hemicellulose sugars. Around 21.3–27.8% lignin was hydrotropically dissolved at a mesoscale level through accumulation by and complexation with 4-Cl-BSA and its aggregates. The solubilized lignin preserved about 24.7–50.7% of the 61% β-O-4 linkages in the native lignin and about 48.3–82% aromatic units uncondensed. About 72.2–78.7% lignin was insolubilized and quickly deposited on the surfaces of cellulose fibers. Remarkably, the deposited lignin preserved about 61.9–81.1% of the β-O-4 linkages in the native lignin and about 78.2–86.2% aromatic units uncondensed. Hemicellulose sugars and cellulose (millimeter-size, CrI: 71–75, DPᵥ: 910–1022) had high purity and high quality. Compared to the other selected aryl sulfonic acids whether they have or do not have substituents (dichloro, bromo, hydroxyl, and methyl) and mineral acids, 4-Cl-BSA performed better in fractionating unmilled poplar chips and preserving the β-O-4 linkages and aromatic units of lignin. The results indicate that both acidity and hydrophobicity of aryl sulfonic acid greatly influence its fractionation and preservation performances.

Objective The L1 cell adhesion molecule (L1CAM) gene, encodes the L1 cell adhesion molecule, is involved in the central nervous system development. Its mutations result in L1 syndrome which is associated with brain malformation and nervous developmental delay. Case report We presented three fetuses with hydrocephalus and agenesis of the corpus callosum detected by ultrasound, followed by medical exome sequencing (MES) test with L1CAM mutations: two known missense mutation c.551G > A (p. R184Q) and c.1354G > A (p. G452R), and a novel frameshift mutation c.1322delG which causes the early termination of translation (p. G441Afs∗72). By utilizing multiple computational analysis, all the variants were scored to be likely pathogenic. Conclusion Combined use of ultrasound and MES to identify the molecular etiology of fetal anomalies may contribute to expanding our knowledge of the clinical phenotype of L1 syndrome observed in the south Chinese population.

The complete and mild-condition fractionation of woody biomass without energy-intensive size reduction still remains a significant challenge. This study reports an innovative cellulose-centred fractionation process based on bifunctional, recyclable, inexpensive, and lignin-derivable phenol-4-sulfonic acid (PSA). The results showed that aqueous PSA solution (e.g., 72 wt%) near-completely fractionated centimetre-sized hardwood, such as poplar and birch chips, into cellulose fibres of high quality (length: >1 mm, crystallinity index: 61–65, DPv: 830–887), fermentable hemicellulose sugars, and lignin in theoretical maximum yields under mild conditions (e.g., 50–80 °C, 0.5–3 h, atm). Calculations and experimental results suggest that PSA, as a small amphiphile, could form aggregates and clusters in water. Therefore, during fractionation, PSA acted as not only a selective catalyst through the immobilized sulfonic acid groups to depolymerize hemicellulose and lignin, but also as a mesoscale solvent to solubilize and protect lignin fragments through aggregates and accumulating around them due to the hydrophobic effect.

Hand action recognition is an important part of intelligent monitoring, human–computer interaction, robotics and other fields. Compared with other methods, the hand action recognition method using skeleton information can ignore the error effects caused by complex background and movement speed changes, and the computational cost is relatively small. The spatial-temporal graph convolution networks (ST-GCN) model has excellent performance in the field of skeleton-based action recognition. In order to solve the problem of the root joint and the further joint not being closely connected, resulting in a poor hand-action-recognition effect, this paper firstly uses the dilated convolution to replace the standard convolution in the temporal dimension. This is in order to process the time series features of the hand action video, which increases the receptive field in the temporal dimension and enhances the connection between features. Then, by adding non-physical connections, the connection between the joints of the fingertip and the root of the finger is established, and a new partition strategy is adopted to strengthen the hand correlation of each joint point information. This helps to improve the network’s ability to extract the spatial-temporal features of the hand. The improved model is tested on public datasets and real scenarios. The experimental results show that compared with the original model, the 14-category top-1 and 28-category top-1 evaluation indicators of the dataset have been improved by 4.82% and 6.96%. In the real scene, the recognition effect of the categories with large changes in hand movements is better, and the recognition results of the categories with similar trends of hand movements are poor, so there is still room for improvement.

Combined Oxidative Phosphorylation Deficiency 23 (COXPD23) caused by mutations in GTPBP3 gene is a rare mitochondrial disease, and this disorder identified from the Chinese population has not been described thus far. Here, we report a case series of three patients with COXPD23 caused by GTPBP3 mutations, from a severe to a mild phenotype. The main clinical features of these patients include lactic acidosis, myocardial damage, and neurologic symptoms. Whole genome sequencing and targeted panels of candidate human mitochondrial genome revealed that patient 1 was a compound heterozygote with novel mutations c.413C > T (p. A138V) and c.509_510del (p. E170Gfs∗42) in GTPBP3. Patient 2 was a compound heterozygote with novel mutations c.544G > T (p. G182X) and c.785A > C (p.Q262P), while patient 3 was a compound heterozygote with a previously reported mutation c.424G > A (p.E142K) and novel mutation c.785A > C (p.Q262P). In conclusion, we first describe three Chinese individuals with COXPD23, and discuss the genotype-phenotype correlations of GTPBP3 mutations. Our findings provide novel information in the diagnosis and genetic counseling of patients with mitochondrial disease.

Paper based humidity sensors are low-cost, flexible, and biodegradable. However, the previously reported paper based humidity sensors exhibit poor repeatability, low sensitivity, high drift, and slow response. Here, we reported a new strategy to monolithically fabricate humidity sensor based on porous paper (PPHS) using robust and precise screen and gravure printings. PPHS is highly sensitive, with the maximum 1480% change at 1 kHz and the maximum 411.4% change at 10 kHz in capacitance, respectively. PPHS is highly repeatable (a 1.05% standard derivation in sensitivity for 3 continuous runs) and is stable and insensitive to a mild temperature change (15-30 °C). PPHS rapidly responds (0.8 s) and recovers (0.78 s). PPHS is also highly foldable and twistable. The high repeatability, high sensitivity, quick response/recovery, high foldability/twistability, and good stability of PPHS could be attributable to the combined effects of the high specific surface area of porous paper and the robust and precise printings. By comparison, PPHS is more sensitive than the previously reported paper-based humidity sensors and several humidity sensors fabricated using different substrates, materials, and printings. Due to these unique features, PPHS shows great potential applications in the humidity sensing, the breath detection, the proximity detection, and non-touch switch.

Combined Oxidative Phosphorylation Deficiency 23 (COXPD23) caused by mutations in GTPBP3 gene is a rare mitochondrial disease, and this disorder identified from the Chinese population has not been described thus far. Here, we report a case series of three patients with COXPD23 caused by GTPBP3 mutations, from a severe to a mild phenotype. The main clinical features of these patients include lactic acidosis, myocardial damage, and neurologic symptoms. Whole genome sequencing and targeted panels of candidate human mitochondrial genome revealed that patient 1 was a compound heterozygote with novel mutations c.413C > T (p. A138V) and c.509_510del (p. E170Gfs∗42) in GTPBP3. Patient 2 was a compound heterozygote with novel mutations c.544G > T (p. G182X) and c.785A > C (p.Q262P), while patient 3 was a compound heterozygote with a previously reported mutation c.424G > A (p.E142K) and novel mutation c.785A > C (p.Q262P). In conclusion, we first describe three Chinese individuals with COXPD23, and discuss the genotype-phenotype correlations of GTPBP3 mutations. Our findings provide novel information in the diagnosis and genetic counseling of patients with mitochondrial disease.

In this paper, the flexibility of bearing parts and localized defects are considered, and a method for calculating the radial time-varying stiffness of flexible cylindrical roller bearings (CRBs) with localized defects is proposed. The proposed method uses the finite element (FE) method to calculate the global flexibility of bearing parts and adopts the analytical contact theory to calculate the localized contact flexibility of bearing parts. Furthermore, based on the displacement excitation assumption, localized defect models of the outer race, inner race, and roller are established. The proposed method is verified by comparing with the methods in the references and the finite element method. The effect of different angles of defect width on time-varying stiffness is discussed. The results show that as the angle of defect width increases, the width of the stiffness saltation also gradually increases. Besides, the calculation accuracy of the proposed method is higher than that of the classical analytical method, and the computational efficiency is greatly improved compared with the finite element method. This study can provide a theoretical basis for defect diagnosis of CRBs.

We have previously demonstrated that anti-CD44s H4C4 or liposomal-delivered STAT3 inhibitor FLLL32 sensitized pancreatic cancer cells to radiotherapy through the elimination or inhibition of cancer stem cells (CSCs) and that HAb18G/CD147 promoted STAT3-mediated pancreatic tumor development by forming a signaling complex with CD44s. In this paper, we therefore explored whether anti-CD147 HAb18IgG sensitized pancreatic cancer cells to chemoradiotherapy via the targeting of CSCs. We tested the influence of HAb18IgG on the sensitivity of pancreatic cancer cells to chemoradiotherapy by clonogenic and MTT assays and on pancreatic CSCs by colony and sphere formation assays, flow cytometry, quantitative real-time RT-PCR (qRT-PCR) and stem cell transcription factors PCR array analysis. Changes in CD147 signaling were examined by immunoblot and reporter assays. We found that HAb18IgG sensitized pancreatic cancer cells to chemoradiotherapy by dose-dependently decreasing colony and sphere formation. Furthermore, HAb18IgG reduced the pancreatic CSC subpopulation and the expression of stem cell transcription factors OCT4, SOX2 and NANOG. Mechanistically, HAb18IgG inhibited CSCs by blocking CD44s-pSTAT3 signaling. The present findings indicated the promising therapeutic role of anti-CD147 HAb18IgG in suppressing pancreatic tumor initiation and overcoming post-chemoradiotherapy recurrence through the direct targeting of CSCs.

According to the initial design parameters of electric submersible pump and the profile equation of blade, the 3D model of impeller and internal flow passage of electric submersible pump is established in Pro/E. By using the APDL parametric modeling function of ANSYS, the optimal analysis model is established. The design variables, target variables and constraints were selected by referring to the relevant books and empirical formulas, and the structure was optimized by using the ANSYS optimization tool. The parameters before and after optimization of the impeller structure under the same viscosity and the optimization parameters of the different oil viscosity coefficients were compared to obtain the influence of each design variable on the performance of the ESP and the optimum parameters under different viscosity coefficients law, which provides a reference for determining the main design parameters of the electric impeller structure of ESP in offshore oilfield.

Jacquard wall cloth based on national flavor should associate with the interior designer. Jacquard wall cloth developes floral pattern as a starting point and combines traditional Chinese elements with modern fashion elements. Choosing a modern Chinese-style room as the main carrier and combining patterns, color and construction to create a jacquard wall cloth.The patten focus on traditional culture and modern geometric perfection,which should associate with each other.The color is taken from Chinese traditional color series,which is suitable for the amenity room environment.Meanwhile the weft and warp yarns are low elastic polyester yarn, which has a sense of lightless,strong and durable.The fabric is constructed with satin weave .This designs achieve an optimal combination of traditional and fashionable benefits.

Due to recent increasing life standards and the development of social civilization, the demands for bedding’s modeling, aesthetic and comfort are greatly improved. At the same time, health is considered as an important factor in the design concept of modern bedding, and also health consumption become one of the main characters in modern bedding consumption. With the study on the principle of bedding-related human engineering, some quantitative theoretical data are summarized, to make the bedding modeling design more scientific. Also, a novel design of bedding series (focused on the bolster and back cushion) which makes the bedding more extensive and depth in application is adopted in this paper.

Four candidates of eclipsing multiples, based on new extraneous eclipses found on Kepler binary light curves, are presented and studied. KIC 7622486 is a double eclipsing binary candidate with orbital period of 2.2799960 days and 40.246503 days. The two binary systems do not eclipse each other in the line of sight, but there is mutual gravitational influence between them which leads to the small but definite eccentricity 0.0035(0.0022) on the short 2.2799960 days period orbit. KIC 7668648 is hierarchical quadruple system candidate, with two sets of solid 203(+-5) days period extraneous eclipses and another independent set of extraneous eclipses. A clear and credible extraneous eclipse is found on the binary light curve of KIC 7670485 which made it a triple system candidates. Two sets of extraneous eclipse of about 390 days and 220 days period are found on KIC 8938628 binary curves, which not only confirms the previous conclusion of $388.5(+-0.3) triple system, but also proposed a new additional objects that make KIC 8938628 a hierarchical quadruple system candidates. It is wished that the four candidates here will make some contributions to the field of eclipsing multiples., 16 pages, 7 figures

There are low porosity and permeability in the Jurassic sandstone in the Yongjin Block, Junggar Basin. Reservoir is main controlled element of petroleum accumulation. It is adverse to hydrocarbon pool. However, unconformity effectively promotes the porosity and permeability of sandstone under it. An important unconformity between Jurassic and Cretaceous Periods developed in the central Junggar Basin. The chemical index of alteration (CIA) values indicate that it experienced physical weathering during development, transported the matrix off the semi-weathering rock, and consequently improved the reservoir quality of sandstone. Water with organic acids that are generated during organic matter maturation could dissolve the feldspar in semi-weathered zone, and would remove the dissolved products from the sandstone. All these would further improve reservoir quality. There are tight sandstone of the Jurassic which is adverse to hydrocarbon accumulation. However, because unconformtiy ocured and experienced the reservoir-improved geologic progresses. The semi-weathered zone of J/K unconformity became the preferred pathway for petroleum migration due to these two geological processes. The Paleo-soil layer on top of the J/K unconformity formed a good trap for the passing hydrocarbons, and accumulated it to become a commercial petroleum pool.

Shale gas is an important unconventional natural gas resource. There is probably abundant shale gas resource in the Longmaxi Formation of the lower Silurian, Sichuan Basin, West China. Longmaxi Formation is high quality source rock, its TOC(total organic carbon) up to the most vulue 6.5 percent; the Formation more than 1percent TOC is up to 105 meters. Because of high maturity, it cannot identify the kerogen type by element Carbon and Hydron ratio, rather than carbon isotopic value. The isotopic carbon values of Kerogens are more than 29.67 permillage, which showed One Type Kerogen. In the Longmaxi Formation, source rock is up to post maturity and lack of vitrinite, so vitrinite reflectance cannot measure the source maturity. It can measure bitumen reflectance, then calculate relevant vitrinite reflectance (Ro) by bitumen reflectance to identify the organic matter thermal evolution degree. The result showed the maturity degree of organic matter equal to more than 3 percent vitrinite reflectance (Ro), which showed the source rock yielded rich thermogenic gas during the geological thermal evolution. The source rock of Longmaxi Formation has some silt partly composed of quartz mineral, up to 40 percent, which is beneficial to gas reservoir. So, it has available shale gas developed elements because of rich organic matter, high thermal maturity degree, good pool. The geological analogy method is used to assess the resource potential. Sichuan Basin has drastically similar to Michigan Basin and San Juan Basin in basin type, seal conditions, reservoir states, source rock, matched condition and so on. So they are selected as standard basin. Sixteen parameters are used to appraise the shale gas pool geological conditions. Compared with Michigan Basin and San Juan Basin by analogy method, Longmaxi Formation shale gas potential is 0.06-0.36 billion cubic meter per square kilometer.

Analysis on the deposition behavior of spray on deposition surface was made and an optimization method for the movement parameters (u, ω) of substrate was obtained. Simultaneously, a mathematical model of growth of tubular preform, specifically aimed at the kind of atomizer that is fixed and with a tilt angle was established. By integrating the optimization method and the mathematical model, the growth process and shape of preform were simulated. The results show that the tilt angle of atomizer plays an important role on the dimensions and shapes of tubular preforms and it can provide a guidance for the development of spray forming equipment.

A three-dimensional mathematical model of growth, integrated with a new and effective algorithm for visibility checking, has been established based on a spray forming equipment with three different fixed atomizers in this paper. The model was used to predict the geometrical shape and the thickness profiles of the tubular deposit under various situations. By investigating and discussing the effects of different mandrel movement parameters and spray heights, the optimal atomizer of the equipment to fabricate a tubular preform was identified numerically.

Satisfiability modulo theories (SMT) play a key role in verification applications. A crucial SMT problem is to combine separate theory solvers for the union of theories. In previous work, the simplex method is used to determine the solvability of constraint systems and the equalities implied by constraint systems are detected by a multitude of applications of the dual simplex method. We present an effective simplex tableau-based method to identify all implicit equalities such that the simplex method is harnessed to an irreducible minimum. Experimental results show that the method is feasible and effective.

For the truss structure composed of active-elements with piezoelectric patches affixed to its surface, taking the mechanical-electric coupling effect under the action of electric loads and mechanical loads into consideration, the finite element model for static force analysis is established by using the theory of mechanics. The failure mechanism of piezoelectric elements is discussed and the failure criteria of piezoelectric elements are proposed. The expression of safety margins for the element of piezoelectric truss structure is proposed with fracture strength, damage electric field strength, the section area of elements, and loads as random variables. On the basis of the research, the stochastic finite element method and structural reliability theory are used to analyze the reliability of the piezoelectric truss structure. An example is given to demonstrate the validity of this method.

A mathematical model was developed for the simulation of gas flow, combustion and heat convection in the vacuum chamber of RH-KTB process at Baosteel. Under different conditions, the model was used to predict the influence of the top oxygen blowing lance on the gas flow; chemical reactions and temperature distribution were calculated. The optimum position of the lance is suggested for the RH-KTB process.

The metal spray forming process was examined using the mathematical model simulation by Baosteel's test and developed facilities. The mathematical model comprised of the probability and statistical analysis of the droplet mass behavior and predicted the shape and temperature distribution of the billet during the spray forming process.

In the piezoelectric truss structure with many random parameters under incipient defect, taking into consideration the mechanical-electric coupling effect under electric load and mechanical load, the formula of safety margins of bar have been proposed by the fracture intensity, bar section area and loads as random variables. On the base of above research, stochastic finite element method is adopted to attempt to analyze reliability of the piezoelectric truss structure. In the end, the example is given to demonstrate the influence of voltage and of damage on reliability index of the piezoelectric truss system.

The simulation software of compressible gas flow process in spray forming equipment was developed under three-dimensional cylindrical coordinates. When the gas flow strands sprayed from some definite angles into the atomizer chamber, they converged at the definite height in axial line then expanded outside which showed the jet current characteristic. The substrate stagnated the divergence jet strands of gas and then separated the flow strand into two big recycle zones in whole space. One of the recycle flow zone directed downwards, the other recycle flow zone, directed upwards and reached the inlet area, which is the main reason caused the bonding of small liquid drop in the delivery hole.

Through the probability simulation method, the statistical model of mass metal liquid droplets during metal spray forming process was developed and the ejecting process of molten steel was studied. The distribution of metal liquid droplets, their different initial velocity and the original appear location during spray forming were obtained based on the above computation. After made statistic and analyzed on large number of metal liquid droplets, the forming and motion of liquid drop in whole space were defined in detail, which provided the precondition and reference for further study of liquid droplets deposition process on substrate.

In the present paper, applied the experiential correlation, the gas holdup and distribution of two phase zone which formed by argon blown were determined. The flow variables of molten steel and turbulence parameters in the Ladle Furnace were estimated utilizing the results of frontal calculation and through numerically solution momentum Navier-Stokes equation in conjunction with k-εturbulence model. Several different spray styles including blowing through single hole, double holes, top lance were simulated and compared in this project.