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41.
Hiroya Oka Yuji Maruki Haruo Suemitsu Takami Matsuo 《International Journal of Control, Automation and Systems》2016,14(5):1270-1279
In this paper, we deal with the control method for rotational movements of a pendulum using a separatrix. We design a controller that attains a homoclinic motion or a heteroclinic motion of the pendulum and the asymptotic stability of the cart by using a kind of forwarding control design. First, we derive a controller that converges to a homoclinic orbit via a Lyapunov function of the pendulum subsystem. Next, we give a nonlinear stabilizing controller via another Lyapunov function of the cart subsystem. Moreover, using the third Lyapunov function and adding a complementary control input, we guarantee that the pendulum converges to the homoclinic orbit and the cart is stabilized. Finally, the simulation and the experiment using the rapid controller prototyping system based on MATLAB/Simulink are performed to demonstrate the forward upward circling and the giant swing of the pendulum. 相似文献
42.
S Matsuo Y Takeuchi S Hayashi A Kinugasa T Sawada 《Canadian Metallurgical Quarterly》1994,10(3):237-240
A patient with unusual Hutchinson-Gilford syndrome (progeria) is reported. This 7-year-old boy had all the characteristics of progeria, except for coxa valga and the "horse-riding" stance. A previous cerebral infarction was detected in the right putamen on cranial magnetic resonance imaging. During treadmill exercise test electrocardiography, ST depression suggested the existence of arteriosclerotic lesions. Skin fibroblast culture exhibited 76% DNA-repair capacity compared to normal. He has not manifested endocrinologic abnormalities. From these findings it is concluded that this patient has an incomplete case of Hutchinson-Gilford syndrome and that a correlation may exist between the clinical features and the degree of DNA-repair capacity. 相似文献
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44.
Yue WangAuthor Vitae Yasushi HasebeAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(2):722-729
Horseradish peroxidase (HRP) was chemically modified using cyanuric chloride (CC) as a linking agent onto a carbon felt (CF), which is a microelectrode ensemble of micro carbon fiber (>7 μm, diameter) with a random three-dimensional structure. The resulting HRP-modified CF (HRP-ccCF) exhibited well-defined redox waves based on the HRP heme FeIII/FeII redox couple at −0.23 V vs. Ag/AgCl (at pH 7.0), while the HRP-adsorbed CF (HRP-CF) showed no apparent redox couple in the same potential range, indicating that the chemical modification of HRP via CC facilitated the direct electron transfer (DET) between HRP and CF. The apparent heterogeneous electron transfer rate constant ks was estimated to be 35 s−1. Cyclic voltammetry and electrochemical impedance spectroscopy revealed that the interfacial properties (i.e., structure, morphology of enzyme-layer) of covalently modified HRP (HRP-ccCF) and physically adsorbed HRP (HRP-CF) are different, resulting in the difference in the electron transfer properties. The HRP-ccCF was successfully used as a working electrode unit in bioelectrocatalytic flow-through detector for highly sensitive amperometric determination of H2O2. Under the optimized conditions (i.e., applied potential, 0 V vs. Ag/AgCl; carrier flow rate, 3.25 ml/min; and carrier pH 7.0), the cathodic peak current of H2O2 linearly increased up to 3 μM (sensitivity, 1.94 μA/μM; the detection limit, 0.08 μM [S/N = 3]) with sample through-put of ca. 90 samples/h. 相似文献
45.
Land surface albedo is one of the key parameters in the radiation budget, the hydrological cycle and climate modeling studies. It is now widely understood that large errors may occur in the estimation of surface albedo without taking into consideration the anisotropy reflectance effect, which is a general feature of the earth surface. Two major anisotropic correction methods exist for the retrieval of land surface albedo under clear sky conditions. One method involves linearly converting from top of the atmosphere (TOA) albedo to surface albedo, and another is based on the inversion of the Bidirectional Reflectance Distribution Function (BRDF) model of the surface. In the present study, a new approach that utilizes an empirical model for estimating surface albedo has been proposed for snow free land surfaces under clear sky conditions. We analyzed the bidirectional reflectance data set with numerous samples representing various land cover types, which derived from POLDER/ADEOS-1 multi-angle imagery data and distributed by MEDIAS-France. Through the analysis, an empirical relation between bidirectional reflectance and albedo was established and has been discussed in detail. The proposed model can be used for direct estimation of surface albedo from a single BRF observation when the sun-target-sensor geometry is known. No BRDF model inversion scheme is necessary. The present model has no or weak dependence on the existing land surface classifications, and is insensitive to wavelength. The theoretical absolute accuracy of the estimated albedo is approximately 0.010 for visible (0.4-0.7 μm), 0.023 for near infrared (0.7-3.0 μm) and 0.016 for shortwave (0.2-3.0 μm), respectively. Albedo consistency with viewing geometry has been verified, resulting in good agreement for albedo estimated from various viewing directions. Validation of the satellite estimated albedo derived by the proposed method, using field observations were also presented and results show it can give reasonably accurate estimation. The proposed method is expected to be a suitable candidate for practical applications of albedo estimation for sensors that do not perform multi-angle observations. 相似文献
46.
Yasushi Hosokawa Daiki Urata Akio Doi Toyoo Takata Yoshihiko Abe 《Artificial Life and Robotics》2017,22(3):346-356
The virtual diving experience learning system of “Ama”, Japanese traditional female divers, has been developed to simulate how divers move in a virtual space using the diving interface and utilizing an accelerometer and a gyroscope. This interface not only detects the diving motion but also outputs the movement. Diving motion is shown in the ways of hand motion while standing. Although this makes it possible for a learner to understand the divers’ actions more clearly, this system’s difficulty is in visualizing a divers’ actions including their hands or bodies. Therefore, our study focuses on developing the operation system to reproduce actual ways of Amas’ diving with a virtual human body in a virtual space. First, the motion capture was done in an underwater condition. In the next process, the virtual human body was created. Finally, with the motion viewer, the more vivid actions of the Ama were successfully reproduced much more than in previous attempts. Using this system, the effectiveness of the Amas’ movement learning was confirmed, because a learner practices Amas’ movement. 相似文献
47.
Watanabe M Takemasa I Kawaguchi N Miyake M Nishimura N Matsubara T Matsuo E Sekimoto M Nagai K Matsuura N Monden M Nishimura O 《Proteomics. Clinical applications》2008,2(6):925-935
In the development of novel biomarkers, the proteomic approach is advantageous because using it the cancer-associated proteins can be directly identified. We previously developed a 2-nitrobenzenesulfenyl (NBS) method to improve quantitative proteome analysis. Here, we applied this method to proteomic profiling of colorectal carcinoma (CRC) to identify novel proteins with altered expression in CRC. Each pair of tumor and normal tissue specimens from 12 CRC patients was analyzed, and approximately 5000 NBS-labeled paired peaks were quantified. Peaks with altered signal intensities (>1.5-fold) and occurring frequently in the samples (>70%) were selected, and 128 proteins were identified by MS/MS analyses as differentially expressed proteins in CRC tissues. Many proteins were newly revealed to be CRC related; 30 were reported in earlier studies of CRC. Six proteins that were up-regulated in CRC (ZYX, RAN, RCN1, AHCY, LGALS1, and VIM) were further characterized and validated by Western blot and immunohistochemistry. All six were found to be CRC-localized, either in cancer cells or in stroma cells near the cancer cells. These results indicate that the proteins identified in this study are novel candidates for CRC markers, and that the NBS method is useful in proteome mining to discover novel biomarkers. 相似文献
48.
49.
采用真空蒸发法制备了氨基化锂LiNH2(+2·LiH)薄膜,即首先将Li真空镀膜到金属基板上,然后经氮化、氢化处理合成LiNH2薄膜.此外,真空蒸发法也用于Mg部分置换Li后薄膜的制备.实验结果证明,与传统的粉末状试样相比,薄膜状试样能够在更低的温度下释放出氢气.研究表明采用包括真空蒸发法等非传统方法合成金属络合物储氢材料对进一步提高其储放氢特性具有良好的效果. 相似文献
50.
Junko Hatori Yasumitsu Matsuo Masaru Komukae Seiichiro Ikehata 《Materials Chemistry and Physics》2006,100(2-3):520-523
We have carried out the optical observation, electrical conductivity and 205Tl NMR measurements, and subsequently investigated the origin of the large conductivity above ferroelastic phase transition temperature Tc (=661 K) on the basis of the domain structure and the crystal structure. Electrical conductivity exhibits the discontinuous increase around Tc with increasing temperature and becomes approximately 5 × 10−3 S m−1 above Tc. Moreover, from the 205Tl NMR measurements, it is found that mobile Tl ions exist above Tc. Furthermore, from the analysis of the domain structure based on the crystal structure in the low-temperature ferroelastic phase, it is also found that the anomalously large fluctuations of SeO4 tetrahedrons exist above Tc. It is deduced from these results that the high electrical conductivity above Tc is caused by the mobile Tl ions closely related to the anomalously large fluctuations of SeO4 tetrahedrons accompanied by the ferroelastic phase transition. 相似文献