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141.
An aromatic polyamide-imide (PAI) film was reinforced with a plain cloth of aromatic polyamide fiber (Du Pont, Kevlar 49). The mechanical properties of the composite film were investigated by examination of the temperature dependencies of tensile dynamic mechanical properties, stress relaxation, and tensile stress-strain behaviors. The softening temperature of the composite film was lower than that of a homogeneous PAI film. At a high temperature, Kevlar fibers may act as a thermal conductor and lower the softening point of the PAI composite. The mechanical properties of the composite film at a high temperature are mostly controlled by the PAI matrix.  相似文献   
142.
A new unified FA (Factory Automation) language has been developed. The language is suited for robot control, vision system control and programmable controller (PC) control and enables a unified means for programming. The language is called FA-BASIC and has common functions such as expression, control structure and input/output statement based on BASIC language.

FA-BASIC is composed of three subsystems: FA-BASIC/R for robot control, FA-BASIC/V for vision system control and FA-BASIC/C for PCs.

Many languages have been developed up to now, but most of them were aimed at single purposes. These single purpose languages were too limited when developing an integrated FA system, because several languages and different program-making methods must be mastered.

Using FA-BASIC, programming with mutual interconnections between robots, PCs and vision devices is done by the one common method.

In this paper, the basic design concept and functions of FA-BASIC will be presented, along with the features of FA-BASIC/R and on outline of a robot control system using a standard mechanism-independent intermediate language and standard fundamental modules. Also, for easy programming, an off-line programming system with graphical aids and a menu-selection method which require no special effort to master will be introduced as the only present-day universal robot programming method.  相似文献   

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The availability of the neutrons due to photonuclear reactions has been discussed by using synchrotron radiation with the beryllium targets. The superconducting wiggler with the magnetic field of approximately 10 T, which is installed into an 8 GeV class storage ring, can emit intense and high-energy photons to produce neutrons. By using MCNPX, the simulations were performed for the conceptual design of the neutron beamline to estimate the available intensity and to investigate the shield conditions. The results were discussed in comparison with other research reactors.  相似文献   
148.
Direct imaging of single-walled carbon nanotubes (SWNTs) suspended on pillar-patterned Si or SiO2 substrates is investigated using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The suspended nanotubes are successfully observed by direct TEM imaging and it is seen that they have either individual or bundles of SWNTs. Low energy (< or =2 keV) SEM produces high contrast images of suspended SWNTs. On the contrary, when SWNTs contact a SiO2 substrate, they are imaged using electron-beam induced current. The image brightness depends on the length of SWNTs.  相似文献   
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A mathematical model for grinding wheel redress life is identified by the polynomial theory of complex systems. Wheel speed, feed, grain size and grade are chosen as the independent variables from among the factors considered to have an effect on wheel wear through the identification of the model. The model obtained enables the redress life to be predicted for all combinations of grinding wheel, work material and grinding conditions, and serves as an aid in the optimization of the grinding process.  相似文献   
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