Effective Data-Driven Calibration for a Galvanometric Laser Scanning System Using Binocular Stereo Vision

A new solution to the problem of galvanometric laser scanning (GLS) system calibration is presented. Under the machine learning framework, we build a single-hidden layer feedforward neural network (SLFN）to represent the GLS system, which takes the digital control signal at the drives of the GLS system as input and the space vector of the corresponding outgoing laser beam as output. The training data set is obtained with the aid of a moving mechanism and a binocular stereo system. The parameters of the SLFN are efficiently solved in a closed form by using extreme learning machine (ELM). By quantitatively analyzing the regression precision with respective to the number of hidden neurons in the SLFN, we demonstrate that the proper number of hidden neurons can be safely chosen from a broad interval to guarantee good generalization performance. Compared to the traditional model-driven calibration, the proposed calibration method does not need a complex modeling process and is more accurate and stable. As the output of the network is the space vectors of the outgoing laser beams, it costs much less training time and can provide a uniform solution to both laser projection and 3D-reconstruction, in contrast with the existing data-driven calibration method which only works for the laser triangulation problem. Calibration experiment, projection experiment and 3D reconstruction experiment are respectively conducted to test the proposed method, and good results are obtained

碳纤维复合材料汽车前地板的研制

This paper describes a manufacturing process of automotive front floor made of carbon fiber reinforced plastic (CFRP). The structure of CFRP front floor was determined from the design based on metal Bodyin- White. With the development of material selection,molding process and preform production,a multi-point injection rapid RTM mold has been designed and built for the purpose. A front floor made of carbon fiber reinforced thermosetting epoxy has been fabricated from the device. The sample succeeded in the stiffness,rigidity,and modal tests,combining with a significant weight reduction. The resultant product meets the manufacturer' s technical requirements, indicating that carbon-fiber-composite as the primary structural material in automotive applications is proved to be feasible

基于PLC的碳纤维复合材料打磨喷涂生产线控制系统设计

According to the surface treatment process of carbon fiber composites,the overall plan of the production line about the carbon fiber composites surface polishing and spaying was designed,including the component and functional planning of control system,the design of program flow chart,the selection of PLC analysis,the design of I /O contact distribution,robot communication configuration,and the design of human-machine interface. The whole system design of the production line about the carbon fiber composites surface polishing and spaying were finally realized by the whole machine debugging

Optimization of refined oil logistics considering pipeline-rail combined transportation

The optimization of oil depot inventory is focused in most of the previous researches on the optimization of refined oil logistics, but the reasonable choice of transportation mode and the influence of batch transportation on pipeline transport plan are not considered during decision-making. On this basis, an optimization model of refined oil logistics was constructed under the premise of satisfying the demand of oil products at the oil depot, establishing the objective function of minimizing overall transportation cost and considering the constraints of oil depot demand, storage capacity and transportation capacity. Meanwhile, a pipeline scheduling optimization model was also constructed by setting up the objective function of minimizing the sum of deviations between the actual delivery volume of oils and the demand of the delivery stations along the pipeline, with consideration to the constraints of batch tracking, batch delivery and node flow. Finally, a refined oil logistics plan satisfying the transportation capacity of pipeline was obtained by coupling the above two models into an optimization model of refined oil logistics, considering the pipeline-rail combined transportation, and iteratively solving the logistics plan and pipeline scheduling plan. Specifically, the constructed model was applied to the formulation of a regional logistics plan for refined oil. The optimization results show that the pipeline transportation volume is improved, the mileage of railway transportation is shortened, and the overall logistics cost is reduced by 4.18% compared with the site plan. The research results have some guiding significance for the refined oil marketing enterprises to develop a reasonable logistics plan

A novel heteropolysaccharide isolated from custard apple pulp and its immunomodulatory activity in mouse macrophages and dendritic cells

In this study, a novel heteropolysaccharide (ASPA80-1) with an average molecular weight of 5.48 × 104 Da was isolated and structurally elucidated from custard apple pulp (Annona squamosa) through DEAE-cellulose, Sephadex G-100 and Sephacryl S-300 HR chromatography and spectral analysis. ASPA80-1 is a water-soluble polysaccharide and it is a polymer consisting of predominant amounts of (1 → 3)-linked-L-arabinose (Ara) residues, small amounts of (1 → 6)-linked-D-galactose (Gal), (1 → 3,5)-linked-L-arabinose (Ara) residues and terminal linked-L-arabinose (Ara) residues, trace amount of (1 → 4)-linked-D-glucose (Glc) residues and (1 → 2)-linked-L-rhamnose (Rham) residues. ASPA80-1 showed significant effect on antigen-presenting cells (APCs) activation. On the one hand, ASPA80-1 activated RAW264.7 macrophage cells by inducing morphology change, enhancing phagocytic ability, increasing nitric oxide (NO) secretion and promoting expression of major histocompatibility complex class II (MHC II) and cluster of differentiation 86 (CD 86). On the other hand, ASPA80-1 promoted the maturation of dendritic cells (DCs) by inducing longer dendrites, decreasing phagocytic ability and increasing MHC II and CD86 expression. Furthermore, mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signaling pathways were activated after the intervention of ASPA80-1 on RAW264.7 cells or DCs. Thus, the novel heteropolysaccharide ASPA80-1 has the potential to be used as an immunoenhancing component in functional foods

A high body mass index strengthens the association between the time of eye rubbing and keratoconus in a Chinese population: a case control study

Abstract Background Although body mass index (BMI) and eye rubbing are linked to an increased risk of keratoconus (KC), the interactive effect of eye rubbing and BMI on KC is largely unknown. This study aimed to evaluate the independent and interactive effects of BMI and eye rubbing on KC and to further explore the role of environmental factors on the occurrence of KC. Methods A total of 621 individuals (291 KC patients and 330 control individuals) were enrolled in this hospital‑based study on KC patients in Central China after individuals missing BMI data were excluded. BMI was calculated as weight in kilograms divided by the square of height in meters. Data on eye rubbing was recorded through face-to-face interviews. Generalized linear regression models were used to analyze associations among BMI, eye rubbing and KC. Interaction plots were used to describe the interactive effects of BMI and eye rubbing on KC. Results The β and 95% confidence interval (CI) were 0.923 (0.112, 1.733) (p = 0.026) and 3.356 (1.953, 4.759) (p < 0.001), respectively, for the effect of each 10 kg/m2 increase in BMI and each 1 min increase in eye rubbing on KC. The interaction of BMI and eye rubbing were positively correlated with KC (p < 0.001). Conclusion These findings suggested that a high BMI aggravated the negative effect of eye rubbing on KC, implying that individuals with a high BMI may be more susceptible to exposure to eye rubbing, which is related to an increased risk of KC