488 research outputs found
Development of ultrasonic motor with a coil type stator and its application to vascular endoscope
IVUS (Intravascular Ultrasound) is a useful medical device to observe the thrombus in blood vessels, and such a micro motor less than 1.0 mm in outer diameter is desired to apply IVUS in narrow brain vessels. In our previous works, ultrasonic motor consisting of a wire coil type stator, a waveguide, a cylindrical rotor, an ultrasonic vibrator has been developed. This motor is rather easy to miniaturize because of its simple structure. However, this motor behavior is unstable rotate. To improve these problems, a foil type stator has been applied in stead of a wire coiled stator. An ultrasonic motor with 0.05 mm thick foil type stator was manufactured and tested their performances. It was able to verify that this ultrasonic motor with a foil type stator has the right quality. So, simplified IVUS system using ultrasonic motor with a foil type stator was manufactured and tested their fundamental performances. In order to expand development of new application, ultrasonic motor with a shortened waveguide and ultrasonic motor integrated driving unit with a stator was developed
Evaluating the Thermal Performance of Retrofitted Lightweight Green Roofs and Walls in Sydney and Rio de Janeiro
© 2017 The Authors. With increasing densification in urban settlements, environmental issues are a challenge in the sustainable development of all cities globally. Considering that the built environment releases almost half of the total greenhouse gas emissions, an effective solution to mitigating the impacts of increasing temperatures can be the improved performance of existing buildings. Furthermore 87% of the buildings we will have in 2050 are already built. Retrofitting roofs and walls with a living vegetated system such as green roofs and walls could be an upgrade option, increasing sustainable construction. The benefits are improved thermal performance but also improved air quality, stormwater attenuation, increased bio-diversity and lower heating and / or cooling energy consumption. No empirical data exists for Sydney and Rio de Janeiro and the question is; what is the extent of thermal improvement with retrofitted green walls and roof in timber framed and blockwork structures? This study analyses both effects and benefits of the green roofs and walls through an experiment in two countries: one in Sydney, Australia; a timber framed construction, and another one in Rio de Janeiro, Brazil; with blockwork construction. This difference in the material choice was made according to the most common type of construction for housing in each country. In each site, the walls and the roof of one of the prototypes were covered with plants and compared to the performance of an unplanted but otherwise identical prototype. The thermal performance was analysed by observing the temperature variation simultaneously in a non-vegetated and vegetated structure. The initial findings show that the combination of green roof and green walls have a relevant role in temperature attenuation. These results indicate, that this lightweight retrofit green technology could not only represent an important advance on sustainable development, but can that it also lead to more comfortable internal conditions for humans living in dense urban environments
Anisotropic softening of collective charge modes in the vicinity of critical doping in a doped Mott insulator
Momentum resolved inelastic resonant x-ray scattering is used to map the
evolution of charge excitations over a large range of energies, momenta and
doping levels in the electron doped Mott insulator class
NdCeCuO. As the doping induced AFM-SC
(antiferromagnetic-superconducting) transition is approached, we observe an
anisotropic softening of collective charge modes over a large energy scale
along the Gamma to (\pi,\pi)-direction, whereas the modes exhibit broadening
( 1 eV) with relatively little softening along Gamma to (\pi,0) with
respect to the parent Mott insulator (x=0). Our study indicates a systematic
collapse of the gap consistent with the scenario that the system dopes
uniformly with electrons even though the softening of the modes involves an
unusually large energy scale.Comment: 5 pages + 5 Figure
Development of ultrasonic motor with a coil type stator and its application to vascular endoscope
IVUS (Intravascular Ultrasound) is a useful medical device to observe the thrombus in blood vessels, and such a micro motor less than 1.0 mm in outer diameter is desired to apply IVUS in narrow brain vessels. In our previous works, ultrasonic motor consisting of a wire coil type stator, a waveguide, a cylindrical rotor, an ultrasonic vibrator has been developed. This motor is rather easy to miniaturize because of its simple structure. However, this motor behavior is unstable rotate. To improve these problems, a foil type stator has been applied in stead of a wire coiled stator. An ultrasonic motor with 0.05 mm thick foil type stator was manufactured and tested their performances. It was able to verify that this ultrasonic motor with a foil type stator has the right quality. So, simplified IVUS system using ultrasonic motor with a foil type stator was manufactured and tested their fundamental performances. In order to expand development of new application, ultrasonic motor with a shortened waveguide and ultrasonic motor integrated driving unit with a stator was developed
Development of ultrasonic motor with a coil type stator and its application to vascular endoscope
IVUS (Intravascular Ultrasound) is a useful medical device to observe the thrombus in blood vessels, and such a micro motor less than 1.0 mm in outer diameter is desired to apply IVUS in narrow brain vessels. In our previous works, ultrasonic motor consisting of a wire coil type stator, a waveguide, a cylindrical rotor, an ultrasonic vibrator has been developed. This motor is rather easy to miniaturize because of its simple structure. However, this motor behavior is unstable rotate. To improve these problems, a foil type stator has been applied in stead of a wire coiled stator. An ultrasonic motor with 0.05 mm thick foil type stator was manufactured and tested their performances. It was able to verify that this ultrasonic motor with a foil type stator has the right quality. So, simplified IVUS system using ultrasonic motor with a foil type stator was manufactured and tested their fundamental performances. In order to expand development of new application, ultrasonic motor with a shortened waveguide and ultrasonic motor integrated driving unit with a stator was developed
Slave-Boson Three-Band Model with O-O Hopping for High-Tc Superconductors
Slave boson mean-field approximation is carried out analytically for weakly
doped CuO_2 conduction planes, characterized by Cu-O charge transfer energy
\Delta_{pd}, Cu-O hopping t_0, O-O hopping t' and repulsion U_d between holes
on Cu site taken as infinite. At zero doping \delta, finite negative
t',|t'|<t_0/2, expands the range of stability of the covalent, conducting state
on the expense of the insulating state which, however, remains stable at larger
\Delta_{pd}. For sufficiently large \Delta_{pd} the renormalized charge
transfer energy saturates at 4|t'| instead of decreasing to zero, as at t'=0
case. In contrast to t', finite \delta suppresses the insulating state nearly
symmetrically with respect to the sign of \delta. The regime with charge
transfer energy renormalized close to 4|t'| fits remarkably well the ARPES
spectra of Bi2212 and LSCO, and, in the latter case, explains the observed
strong doping dependence of the Cu-O hopping.Comment: 4 pages, 2 figure
ESTIMATION OF CANCER RISK BY BENZENE EMITTED FROM VEHICLES
Joint Research on Environmental Science and Technology for the Eart
A METHOD OF BENZENE EXPOSURE ESTIMATION CONSIDERING THE INFLUENCE OF THE BUILDING FORM FACED TO MAIN
Joint Research on Environmental Science and Technology for the Eart
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