Stepwise Model Reconstruction of Robotic Manipulator Based on Data-Driven Method

Research on dynamics of robotic manipulators provides promising support for model-based control. In general, rigorous first-principles-based dynamics modeling and accurate identification of mechanism parameters are critical to achieving high precision in model-based control, while data-driven model reconstruction provides alternative approaches of the above process. Taking the level of activation of data as an indicator, this paper classifies the collected robotic manipulator data by means of K-means clustering algorithm. With the fundamental prior knowledge, we find the corresponding dynamical properties behind the classified data separately. Afterwards, the sparse identification of nonlinear dynamics (SINDy) method is used to reconstruct the dynamics model of the robotic manipulator step by step according to the activation level of the classified data. The simulation results show that the proposed method not only reduces the complexity of the basis function library, enabling the application of SINDy method to multi-degree-of-freedom robotic manipulators, but also decreases the influence of data noise on the regression results. Finally, the dynamic control based on the reconfigured model is deployed on the experimental platform, and the experimental results prove the effectiveness of the proposed method.Comment: 8 pages, 11 figure

The extended BLMSSM with a 125 GeV Higgs boson and dark matter

To extend the BLMSSM, we not only add exotic Higgs superfields $(\Phi_{NL},\varphi_{NL})$ to make the exotic lepton heavy, but also introduce the superfields($Y$,$Y^\prime$) having couplings with lepton and exotic lepton at tree level. The obtained model is called as EBLMSSM, which has difference from BLMSSM especially for the exotic slepton(lepton) and exotic sneutrino(neutrino). We deduce the mass matrices and the needed couplings in this model. To confine the parameter space, the Higgs boson mass $m_{h^0}$ and the processes $h^0\rightarrow \gamma\gamma$, $h^0\rightarrow VV, V=(Z,W)$ are studied in the EBLMSSM. With the assumed parameter space, we obtain reasonable numerical results according to data on Higgs from ATLAS and CMS. As a cold dark mater candidate, the relic density for the lightest mass eigenstate of $Y$ and $Y'$ mixing is also studied

An Invasive Whitefly Feeding on a Virus-Infected Plant Increased Its Egg Production and Realized Fecundity

Plant-pathogenic begomoviruses have a complex association with their insect vectors. The interactions of begomoviruses and reproduction of their vectors are poorly understood. Bemisia tabaci is known to transmit many begomoviruses, and the spread of B. tabaci, especially the B and Q 'biotypes', has been accompanied by the epidemics of begomoviruses. One of these identified disease-causing agents was Tomato yellow leaf curl China virus (TYLCCNV).In this study, we compared the egg production and realized fecundity of two 'biotypes' or putative species of the whitefly B. tabaci, including the alien invasive B and the indigenous ZHJ1 from Zhejiang, China, feeding on either healthy or TYLCCNV-infected tobacco plants. The ovary of the whitefly was composed of 12-22 telotrophic ovarioles. According to the morphology of the oocytes and level of yolk content, oocytes in ovarioles were divided into four developmental phases (I-IV). Significantly higher proportion of immature oocytes (phase II, III) and mature oocytes (phase IV) was observed in ovary of females that fed on TYLCCNV-infected tobacco compared to that on healthy plants. Moreover, there was significant increase of eggs laid of B whitefly that fed on TYLCCNV-infected tobacco plants during the early developmental stages. In contrast, the proportion of oocytes of different developmental phases and eggs laid had no significant differences between ZHJ1 whiteflies feeding on TYLCCNV-infected and non-infected host plants.The invasive B whitefly benefits from feeding on a begomovirus-infected plant through increased egg production and realized fecundity

Colorectal cancer screening with fecal occult blood test: A 22-year cohort study.

The aim of the present study was to investigate the efficacy of colorectal cancer (CRC) screening with a three-tier fecal occult blood test (FOBT) in the Chinese population. The study was performed between 1987 and 2008 at the Beijing Military General Hospital, in a cohort of army service males and females aged >50 years. Between 1987 and 2005, a three-tier screening program, comprising guaiac-based FOBTs (gFOBTs), followed by immunochemical FOBTs for positive guaiac test samples and then colonoscopy for positive immunochemical test subjects, was performed annually. The cohort was followed up until 2008. The cohort included 5,104 subjects, of which, 3,863 subjects participated in screening (screening group) and 1,241 did not (non-screening group). The two groups did not differ in age, gender or other major risk factors for colon cancer. Overall, 36 CRCs occurred in the screening group and 21 in the non-screening group. Compared with the non-screening group, the relative risk for the incidence and mortality of CRC was 0.51 [95% confidence interval (CI), 0.30-0.87] and 0.36 (95% CI, 0.18-0.71), respectively, in the screening group. The general sensitivity of this three-tier FOBT was 80.6% (95% CI, 65.3-91.1). Thus, annual screening using the three-tier FOBT program may reduce the CRC incidence and mortality rate