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1.
The use of field robots can greatly decrease the amount of time, effort, and associated risk compared to if human workers were to carryout certain tasks such as disaster response. However, transportability and reliability remain two main issues for most current robot systems. To address the issue of transportability, we have developed a lightweight modularizable platform named AeroArm. To address the issue of reliability, we utilize a multimodal sensing approach, combining the use of multiple sensors and sensor types, and the use of different detection algorithms, as well as active continuous closed‐loop feedback to accurately estimate the state of the robot with respect to the environment. We used Challenge 2 of the 2017 Mohammed Bin Zayed International Robotics Competition as an example outdoor manipulation task, demonstrating the capabilities of our robot system and approach in achieving reliable performance in the fields, and ranked fifth place internationally in the competition.  相似文献   
2.
The Co/MFI(SiO2/Al2O3 = 30) were prepared by a precipitation method with NaOCl in alkali solutions exhibited high activities to N2 at 250 °C for the selective catalytic reduction (SCR) of NOx. These catalysts showed two UV–vis bands at 700 and 400 nm, indicating the presence of octahedral Co(III) as well as tetrahedral Co(II). The high SCR activity over such Co(III, II)/MFI(30) seems to come from Co(III)---O moieties. The Co(II)MFI(30) catalysts prepared from Co(II)Cl2 exhibited low SCR activities due to the presence of tetrahedral Co(II) ions in MFI. Less CO formation occurred over Co/MFI catalysts. The Fe/MFI(30) catalyst exhibited high activity due to the presence of some Fe---O species in MFI but more amount of CO were produced during SCR. H/MFI(30) catalyst exhibited a good SCR activity. However, more amount of carbonaceous deposits were produced on it. The correlation between acid concentration and SCR activity was discussed over H/MFIs.  相似文献   
3.
4.
In this paper we present a master–worker type parallel method for finding several eigenvalues and eigenvectors of a generalized eigenvalue problem , where A and B are large sparse matrices. A moment-based method that finds all of the eigenvalues that lie inside a given domain is used. In this method, a small matrix pencil that has only the desired eigenvalues is derived by solving large sparse systems of linear equations constructed from A and B. Since these equations can be solved independently, we solve them on remote servers in parallel. This approach is suitable for master–worker programming models. We have implemented and tested the proposed method in a grid environment using a grid RPC (remote procedure call) system called OmniRPC. The performance of the method on PC clusters that were used over a wide-area network was evaluated.  相似文献   
5.
We previously developed chitosan cryogels from chitosan-gluconic acid conjugate without using toxic additives for wound care. In this study, we improved physiological characteristics of the previous cryogels by incorporating poly(vinyl alcohol) that also form cryogels. Mechanical strength of the cryogels was more than two times higher than that of the previous cryogels. Furthermore, the incorporation of poly(vinyl alcohol) enhanced water retention and resistance to degradation of the gels by lysozyme. The cryogels retained the favorable biological properties of the previous cryogels that they accelerate infiltration of inflammatory cells into wound sites. Time period for repairing 50 % of initial area of partial-thickness skin wound treated with the cryogels (4.0 ± 1.1 days) was shorter than those with gauze (6.5 ± 0.3 days) or a commercial hydrogel dressing (5.7 ± 0.3 days). Finally, we confirmed that incorporation of basic fibroblast growth factor into the cryogels was effective to further accelerate wound healing (2.7 ± 1.0 days). These results demonstrate that the cryogels in this study are promising for wound care.  相似文献   
6.
Photopharmacology has attracted research attention as a new tool for achieving optical control of biomolecules, following the methods of caged compounds and optogenetics. We have developed an efficient photopharmacological inhibitor—azoMTX—for Escherichia coli dihydrofolate reductase (eDHFR) by replacing some atoms of the original ligand, methotrexate, to achieve photoisomerization properties. This fine molecular design enabled quick structural conversion between the active “bent” Z isomer of azoMTX and the inactive “extended” E isomer, and this property afforded quantitative control over the enzyme activity, depending on the wavelength of irradiating light applied. Real-time photoreversible control over enzyme activity was also achieved.  相似文献   
7.
A hybrid tabletop (2 m x 3 m) terawatt chirped-pulse amplification Ti:sapphire-Nd:glass laser (1054 nm, 475 fs, 500 mJ, 9 x 10(17) W cm(-2)) has been developed for laser-matter experiments. An overall gain factor of 10(10) was achieved for the laser. The results of laser applications in the studies of soft-x-ray Ni-like Mo 18.9-nm lasing and of harmonic generation from solid surfaces are presented.  相似文献   
8.
Effects of low-dose cadmium exposure on biological examinations   总被引:13,自引:0,他引:13  
We conducted an epidemiological study to investigate the effects of low-dose cadmium (Cd) exposure on human health in a specific area of a town in Japan where low Cd concentration was detected in rice. We compared clinical findings, urinary and whole blood Cd concentrations, and indicators of renal dysfunction between the polluted area and the control area. The study employed 44 men and 54 women from the polluted area and 21 men and 29 women from the control area. In urine analysis, as indicators of Cd exposure and possible related renal dysfunction, Cd, beta(2)-microglobulin (beta(2)-MG), alpha(1)-microglobulin (alpha(1)-MG), N-acetyl-beta-D-glucosaminidase (NAG), total protein, inorganic phosphorus, lysozyme and creatinine were quantitatively measured. In blood analysis, serum IP and creatinine and whole blood Cd were measured. No case of renal dysfunction due to Cd exposure was confirmed. However, both the urinary and whole blood Cd of the polluted area were significantly higher than those of the control area for both sexes. Urinary beta(2)-MG did not differ between the two areas. For women, urinary alpha(1)-MG was significantly higher in the polluted area than in the control area. In correlation analysis, beta(2)-MG, alpha(1)-MG and NAG, were positively correlated with both of urinary and whole blood Cd for men and women in the polluted area except for between urinary beta(2)-MG and urinary Cd for men. In the control area, the sole positive correlation observed was between urinary beta(2)-MG and whole blood Cd for men. We then examined the determinants of variations of parameters in urinary and blood tests. Potential determinants were age, sex, body mass index, an indicator of smoking habits (cigarette index) and the index of estimated Cd intake from rice (Cd-rice-index). Cd-rice-index was expressed as the product of Cd concentrations in homegrown rice multiplied by daily frequency multiplied by duration (years) of residence in the polluted area. In multiple regression analysis, whole blood Cd was independently associated with Cd-rice-index, age and gender. Variations in whole blood Cd accounted for a substantial portion of the variations in urinary Cd, although they were less influential in older individuals. Whole blood Cd was the sole independent variable related to variations in urinary beta(2)-MG. Cd-rice-index accounted for a portion of the variance in urinary NAG, while age was a more powerful determinant. It was thus revealed that the consumption of homegrown rice polluted with Cd in low concentration resulted in an elevation of whole blood Cd level and consequent increase in urinary Cd level. However, it was not clearly elucidated that the excretion of urinary low-molecular microglobulins could increase significantly in response to slight elevation of Cd body load.  相似文献   
9.
Profile magnetic configuration of a quantized flux line and flux-line lattice penetrating a type-II superconductor thin foil, niobium, was observed by electron holography and Lorentz microscopy using a 300 kV field-emission electron microscope. Each single flux line was distributed periodically as lattice structure in the mixed state just below its critical temperature of 8.5 K, while at low temperature of 5 K the flux lines were weakly bound as bundles. In order to observe the flux-line distribution over a wide area, discrete Fourier transform reconstruction in the holography was extended for a rectangular area without loss of information and data precision.  相似文献   
10.
The electronic states of sodium ion (Na+) trapped on the model surfaces of amorphous carbon have been investigated by means of hybrid density functional theory (DFT) calculations to elucidate the nature of interaction between Na+/Na and the amorphous carbon surfaces. Also, direct molecular orbital-molecular dynamics (MO-MD) calculation [Tachikawa and Shimizu, J. Phys. Chem. B, 110 (2006) 20445] was applied to diffusion processes of the Na+ ion on the model surface of amorphous carbon. Seven models of graphene sheets (n = 7, 14, 19, 29, 37, 44 and 52, where n means numbers of rings in each carbon cluster) were considered in the present study. The B3LYP/LANL2MB calculations showed that the sodium ion is located at 2.24-2.26 Å from the graphene surfaces. The direct MO-MD calculations showed that the Na+ ion diffuses freely on the surface above 300 K. At higher temperature (1100 K), the Na+ ion moved from the center to edge region of the model surface. The nature of the interaction between Na+ and the amorphous carbon surfaces was discussed on the basis of theoretical results.  相似文献   
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