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The coordinate measuring machine (CMM) is one of the most widely used precision measurement machines in the machinery industry. In this study, the analysis and compensation of structural deformation in spatial coordinates effectively depicts the improvement of the spatial accuracy of the motion of a three-dimensional measuring machine in a measurement area. In addition to accuracy, it is also projected that the measurement can be carried out more efficiently. Therefore, the measurement speed of the CMM and dynamic characteristics of the structure are becoming increasingly important. Consequently, the measuring machine has better dynamic characteristics and meets high precision requirements. During measurement, the geometric errors generated by the machine are mainly because of its moving structure in the spatial position. In this study, the CMM is driven by aerostatic bearings; the boundary conditions and parameter settings of each component are established to obtain analysis results that are highly consistent with the actual machine characteristics. The finite element method is used as an analysis tool, including static deformation, modal, spectrum, and transient analyses. Because of the structural deformation and spatial geometric errors caused by the moving structure of the measuring machine, the relative deformation errors can be evaluated through the analysis of the spatial position error compensation to improve the measurement accuracy of the machine.

Soybean is an important food crop in China. Recently, crops cultivated in specific geographical locations have started attracting high prices. Therefore, developing a technique to identify the geographical origin of a crop is crucial to prevent fraud. In this work, we measured the contents of five fatty acids and 17 elements in soybean samples produced in Heilongjiang, the Inner Mongolia Autonomous Region, Jilin and Liaoning using gas chromatography and inductively coupled plasma mass spectrometry. Correlation analysis, principal component analysis and cluster analysis were used to identify the relationship between the metabolic fingerprint and the geographical location. Our results showed a significant correlation between the contents of fatty acids and geographical origin. Principal component analysis provided a preliminary classification of all variables. Hierarchical clustering, based on heat maps, showed that all samples could be classified based on their geographical origins. The model established by partial least squares discriminant analysis showed 89.9% predictive ability, further proving that the 14 classification indexes, comprising fatty acids and elements, could be used as molecular fingerprints to identify and distinguish soybean samples from four different production areas. Besides, pairs of soybean sample fingerprints from the four provinces were compared, and the differences in fatty acid and element contents between the provinces were explained based on the climatic environment and soil distribution. In conclusion, our method of classifying and confirming soybean production areas through fatty acid and multi-element fingerprints can potentially be used for identifying soybean of similar origins.

Aim Osteoarthritis (OA) is the main cause of disability and joint replacement surgery in the elderly. As a crucial cell survival mechanism, autophagy has been reported to decrease in OA. PHF23 is a new autophagy inhibitor which was first reported by us previously. This study aimed to explore the anti-autophagic mechanism of PHF23 to make it a possible therapeutic target of OA. Main method Lentiviral vectors specific to PHF23 were used on chondrocytes (C28/I2) to establish PHF23 overexpressed or knockdown stable cell strains. Interleukin (IL)-1β (10 ng/mL) and chloroquine (CQ, 25 uM) were used as an inducer of OA and inhibitor of lysosome, respectively. Autophagy was evaluated by autophagosome formation using transmission electron microscopy (TEM) and western blot analysis of P62 and LC3B on different groups of cells. Effects of PHF23 on OA were evaluated by collagen II immunofluorescent staining and western blot analysis of OA-associated proteins MMP13 and ADAMTS5. Effects of PHF23 on AMPK and mTOR/S6K pathways and mitophagy were determined by western blot analysis. Key findings Knockdown of PHF23 enhanced IL-1β-induced autophagy, while overexpression of PHF23 exerted the opposite effect. Knockdown of PHF23 protected chondrocytes against IL-1β-induced OA by decreasing the levels of OA-associated proteins and increasing expression of Collagen II. Knockdown of PHF23 also increased mitophagy level and altered the phosphorylation levels of AMPK, mTOR, and S6K. Significance PHF23 downregulates autophagy, mitophagy in IL-1β-induced OA-like chondrocytes and alters the activities of AMPK and mTOR/S6K, which suggests that PHF23 may be a possible therapeutic target for OA.

To correct the color separation of a large format CCD camera,this paper researches the internal structure of the CCD,analyzes the reasons of three color separation of multi-linear-array CCDs and proposes a new correction method to cache three-channel data separately.Then,it establishes the first high-speed tri-CCD large format scanner domestically.On the basis of the internal process structures of the tri-CCD,this correction method caches and restructures the three-channel data in hardware separately,and restores the true color.The theoretical analysis and practical application results show that three-color separation phenomenon has been greatly reformed after treated,and three-channel color is not separation in 1 200 DPI.In 600 DPI,the scan speed of the scanner produced by our team has been up to 5.08 cm/s,and it only takes 30 s to scan a A0 size drawing.Furthermore,the splicing error of the image after scanning will be superior to ±2 pixels.

Multiscale visualization approaches are proposed to efficiently assist designers not familiar with statistical mathematics in determining the optimal process parameter schemes for achieving desired part quality in injection molding, based on which the parameters’ relative importance to part quality and their influence on either single quality index or comprehensive part quality can be visually described by the map of the sum of squared deviations, response surface diagram and distribution map of comprehensive part quality. The proposed visualization approaches are universal for analyzing the effects of process parameters on the quality of any injection-molded plastic parts although the mobile phone cover is utilized as an example in the presentation of our work.

Regarding the problem of microblog growth regulation of net-mediated public sentiment in the propagation process, a complex-network-based modeling approach was proposed. Taking microblog as a research object, by using the approach of growing, adding edge and random adding edge to reflect the characteristics of user's behavior and microblog public opinion dissemination, a microblog net-mediated public sentiment growth mode was built. By using Matlab toolkit, a simulation model was built. Through running this simulation model according to different network scale experiment cases, for example, setting parameters of the initial nodes size and the random adding edges, diagrams could be layout, that illustrating network, degree distribution and probability distribution. Simulation results validated the model's feasibility for studying network public opinion hotspot growth regulation.

Aiming at assisting the document inspectors to identify the seal imprint time, a classification identification method is proposed based on BP NN (Neutral Network). This paper built a seal stamp characteristics index system aided by the recognition experience of famous inspectors, then, extracted and quantized the characteristic parameters. With these parameters, building BP NN training and testing models could help to identify the real range of seal imprint time. The experiment was implemented on the extracted seal characteristics data by using the Matlab Neural Network toolbox. Experiment results demonstrate the effectiveness and feasibility of the seal imprint time classification verification method based on BP NN.