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排序方式: 共有793条查询结果,搜索用时 15 毫秒
91.
Chunquan Xu Aiguo Ming Takeharu Nagaoka Makoto Shimojo 《Journal of Intelligent and Robotic Systems》2009,56(3):277-299
In this paper we discuss our simulation and empirical study of a golf swing motion controller for a two-link golf swing robot.
We distinguish two variants of the whole golf swing termed as hitting problem and stopping problem. For the hitting problem
arising from backswing and downswing, we map the task into the output of a target dynamic system—a harmonic oscillator—under
energy control. For the stopping problem that arises from follow-through, we propose a Proportional plus Gravity and Coupling
Torque Compensation (PGCTC) feedback controller. Preliminary simulation study shows the proposed controllers solve the hitting
problem and the stopping problem respectively. The controllers are implemented on a physical robot. Experimental results indicate
the robot is able to perform desired golf swing-backswing, downswing, and follow-through. We also give a preliminary analysis
on the proposed method to understand its merits and weaknesses. 相似文献
92.
Biofouling control is important for effective process of membrane bioreactor (MBR). In this study, phenomena of biofouling for immersed type extended aeration MBR with two different anti-fouling aeration intensities were studied through a laboratory set up. The objectives of this study were (a) to observe biofouling phenomena of MBR that operates under different anti-fouling bubbling intensity, and simultaneously monitors performance of the MBR in organic carbon and nutrients removal; (b) to compare effectiveness of detergent and detergent-enzyme cleaning solutions in recovering biofouled membranes that operated in the extended aeration MBR. For MBR, which operated under continuous anti-fouling aeration, deposition and accumulation of suspended biomass on membrane surface were prohibited. However, flux loss was inescapable that biofilm layer was the main problem. Membrane cleaning was successfully carried out with detergent-enzyme mixture solutions and its effectiveness was compared with result from cleaning with just detergent solution. 相似文献
93.
Hirotsugu Takizawa Naoto HazeKeisuke Okamoto Kyota UhedaTadashi Endo 《Materials Research Bulletin》2002,37(1):113-121
Iron-doped β-rhombohedral boron was synthesized by 28 GHz microwave irradiation on a powder mixture of iron and β-boron. β-Boron strongly absorbs 28 GHz microwaves, and this strong coupling with microwave energy can be used to promote a reaction with iron dopant. The powder mixture was heated to 1800°C within 2 min by microwave irradiation, resulting in the formation of β-rhombohedral boron interstitially doped with iron. The reaction proceeded rapidly without accompanying grain growth. The XRD analysis and the electrical conductivity measurements revealed successful incorporation of iron into two doping sites of β-boron. 相似文献
94.
A compact and low-polarization crosstalk 1×2 PANDA fiber switch has been developed by precisely aligning the principal axes between the facing fibers. It exhibits an insertion loss of 0.5 dB, a return loss of 42 dB, polarization crosstalk of -30 dB, and a driving power of 9 mW. High-switching reproducibility with a loss change of less than 0.1 dB and a crosstalk change of less than 2 dB were obtained during 104 switching operations 相似文献
95.
K Harada T Sugahara T Ohnishi Y Ozaki Y Obiya S Miki T Miki M Imamura Y Kobayashi H Watanabe M Akashi Y Furusawa N Mizuma H Yamanaka E Ohashi C Yamaoka M Yajima M Fukui T Nakano S Takahashi T Amano K Sekikawa K Yanagawa S Nagaoka 《Canadian Metallurgical Quarterly》1998,1(5):817-822
OBJECTIVE: To explore whether there are different disease patterns of rheumatoid arthritis (RA) in women and men. METHODS: We studied 55 male case patients and 110 female control patients who developed RA between 1970 and 1985 and who resided and received medical care in Olmsted County, Minnesota, for at least 10 years after the diagnosis of RA. Case and control patients were matched for the date of first diagnosis. The pattern and extent of joint involvement, the frequency of joint surgeries, and the presence and type of extraarticular manifestations were determined by retrospective chart review. RESULTS: Incidence rates in women were variable and age dependent, whereas the risk in men older than 36 years was constant over their lifetime. Erosive disease was more frequent in men than in women (72% versus 55%, respectively; P < 0.05) and tended to occur earlier (47% versus 31% for erosive disease within the first 4 years of RA). Although male sex was correlated with a higher risk of bony erosions and an accelerated course of RA, structural consequences of joint destruction were more pronounced in women. Joint surgery was performed more frequently in women (50%) than in men (27%) (P = 0.01). In particular, the frequencies of arthroplasties and arthrodeses of hand and foot joints were different (34 procedures in women versus 1 procedure in men; P < 0.001). Sex influenced the risk as well as the pattern of organ involvement in RA. Nodules and rheumatoid lung disease were typical manifestations in men (P = 0.001 and P < 0.001, respectively), whereas women typically developed sicca syndrome (P = 0.05). Despite differences in disease aggressiveness and disease pattern, there was little difference in the medical therapy in the men compared with the women. CONCLUSION: RA is a heterogeneous disease with variations in phenotype. Sex-associated factors influence disease severity as well as disease pattern. Because sex-related effects influence treatment goals, treatment responses, and side effects, they should be considered in clinical study design and analysis as well as in the treatment decisions for individual patients with RA. 相似文献
96.
General formulas for capacity of classical-quantum channels 总被引:2,自引:0,他引:2
Hayashi M. Nagaoka H. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2003,49(7):1753-1768
The capacity of a classical-quantum channel (or, in other words, the classical capacity of a quantum channel) is considered in the most general setting, where no structural assumptions such as the stationary memoryless property are made on a channel. A capacity formula as well as a characterization of the strong converse property is given just in parallel with the corresponding classical results of Verdu-Han (1994) which are based on the so-called information-spectrum method. The general results are applied to the stationary memoryless case with or without cost constraint on inputs, whereby a deep relation between the channel coding theory and the hypothesis testing for two quantum states is elucidated. 相似文献
97.
Information geometry of Boltzmann machines 总被引:3,自引:0,他引:3
A Boltzmann machine is a network of stochastic neurons. The set of all the Boltzmann machines with a fixed topology forms a geometric manifold of high dimension, where modifiable synaptic weights of connections play the role of a coordinate system to specify networks. A learning trajectory, for example, is a curve in this manifold. It is important to study the geometry of the neural manifold, rather than the behavior of a single network, in order to know the capabilities and limitations of neural networks of a fixed topology. Using the new theory of information geometry, a natural invariant Riemannian metric and a dual pair of affine connections on the Boltzmann neural network manifold are established. The meaning of geometrical structures is elucidated from the stochastic and the statistical point of view. This leads to a natural modification of the Boltzmann machine learning rule. 相似文献
98.
Solid-liquid phase equilibria of the benzene + cyclohexane system have been investigated experimentally at temperatures from 278 to 323 K and pressures up to 500 MPa using a newly designed optical vessel. The uncertainties of the measurements of temperature, pressure, and composition are within ±0.1 K, ±0.5 MPa, and ±0.001 mole fraction, respectively. The solid-liquid equilibrium pressure at a constant composition increases almost linearly with increasin temperature. The eutectic point shifts to a higher temperature and to a benzenerich composition with increasing pressure. This trend is found to agree with the direction predicted by the van Laar equation. The solid-liquid coexistence curves can be expressed by the Wilson equation with a mean deviation of 0.007 and a maximum deviation of 0.029 in mole fraction. 相似文献
99.
We report a novel porous fluorinated polyimide membrane with a cylinder structure fabricated by a wet phase inversion process, which is formed by a ternary system, polyimide/solvent/water. The porous polyimide membranes consisted of a thin top porous layer and three‐dimensionally ordered cylinder micropores. The porous membrane‐forming solvents were N‐methylpyrrolidone containing nonsolvent additives such as alcohol, and the height and width of the cylinder structure were controlled by the solvents. Water fluxes through the porous polyimide membranes were measured using a stirred dead‐end filtration cell, and the fluxes of the porous membrane with the cylinder‐type structure were approximately three times greater than those of the membrane with the finger‐type structure. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3016–3021, 2004 相似文献
100.
Ishikawa M Sekine K Okamura A Zheng YW Ueno Y Koike N Tanaka J Taniguchi H 《Journal of Bioscience and Bioengineering》2011,111(6):711-718
Reconstitution of tissue architecture in vitro is important because it enables researchers to investigate the interactions and mutual relationships between cells and cellular signals involved in the three-dimensional (3D) construction of tissues. To date, in vitro methods for producing tissues with highly ordered structure and high levels of function have met with limited success although a variety of 3D culture systems have been investigated. In this study, we reconstituted functional hepatic tissue including mature hepatocyte and blood vessel-like structures accompanied with bile duct-like structures from E15.5 fetal liver cells, which contained more hepatic stem/progenitor cells comparing with neonatal liver cells. The culture was performed in a simulated microgravity environment produced by a rotating wall vessel (RWV) bioreactor. The hepatocytes in the reconstituted 3D tissue were found to be capable of producing albumin and storing glycogen. Additionally, bile canaliculi between hepatocytes, characteristics of adult hepatocyte in vivo were also formed. Apart from this, bile duct structure secreting mucin was shown to form complicated tubular branches. Furthermore, gene expression analysis by semi-quantitative RT-PCR revealed the elevated levels of mature hepatocyte markers as well as genes with the hepatic function. With RWV culture system, we could produce functionally reconstituted liver tissue and this might be useful in pharmaceutical industry including drug screening and testing and other applications such as an alternative approach to experimental animals. 相似文献