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71.
72.
Yoshio Iwai Shinji Miyamoto Hideaki Ikeda Yasuhiko Arai Shigetoshi Kobuchi Yuji Sano 《Polymer Engineering and Science》1993,33(6):322-327
The mutual diffusion coefficients for styrene-butadiene rubber(SBR)-n-nonane systems were measured using a sorption apparatus with a quartz spring at 100 and 130°C for mass fractions of n-nonane ranging from 0 to 0.16. The mutual diffusion coefficients were correlated with good agreement by the free-volume theory. 相似文献
73.
A highly accelerated humidity test for plastic encapsulated IC reliability short-term evaluation has been studied. 2-Vessel pressure cooker test (PCT) equipment capable of controlling relative humidity and temperature independently, and of keeping specimens free from water droplet condensation, has been designed. This equipment consists of a test chamber and a vapor chamber. Humidity conditions are set by controlling the temperature difference between the test chamber and the vapor chamber. Humidity levels are controlled with the direct pressure adjustment. The whole test chamber is heated in an oven, thereby obtaining temperature stability and uniformity. Using this equipment, humidity tests were carried out on plastic molded ICs. As a result, good test reproducibility and excellent correlation in test results between PCT and conventional humidity test such as 85°C/85%RH, were obtained. As a consequence, it was found possible, in a short time, to evaluate plastic molded IC reliability quantitatively in humidity ambients using this 2-vessel PCT equipment. This equipment can be used for quality assurance testing of plastic-encapsulated ICs in a short time. 相似文献
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The evaporation, carburization and diffusion behavior of Nb-coated Mo and of Nb-coated Ti were investigated in order to estimate the surface characteristics of the coated systems. Nb layers were formed on Mo by both chemical and physical vapor deposition and on Ti by just physical vapor deposition. From the diffusion behavior, interdiffusion coefficients were obtained at 1860°C, 1980°C and 2080°C for the chemically vapor-deposited Nb/Mo system. From evaporation experiments it was found that simultaneous evaporation of Nb and Mo occured at about 2300°C for thick films of Nb on Mo. For thin films of Nb on Mo, the evaporation of both Nb and Mo was confirmed at 1900°C by ion microprobe analysis of the condensate. For Nb/Ti, rapid diffusion of Nb into Ti and evaporation of Ti similar to the case of Nb-Ti alloys were observed. From the carburization study, it was found that an Nb coating appreciably retards the carburization of Ti and Mo. 相似文献
77.
Electron microscopic in situ hybridization (EM-ISH) is a useful method in determining the localization of a specific nucleic acid at the ultrastructural level. Since the EM-ISH protocol includes many steps, no standard protocol for EM-ISH is available yet. In this study, we optimized quantitatively the critical conditions with respect to embedding resin, nucleic acid labeling and hybridization reaction time, by using adenovirus-infected cells as the indicator cells. The optimal detection of an adenovirus-specific nucleic acid was obtained by overnight hybridization reaction on sections embedded in Lowicryl K4M resin. Random-primed-labeled probes improved the reactivity. At least 60% of virus particles in paracrystalline arrays was found to contain viral DNA. These arrays in adenovirus-infected cells are useful in evaluating quantitatively the efficiency of protocols of EM-ISH. 相似文献
78.
In conventional haptic devices for virtual reality (VR) systems, a user interacts with a scene by handling a tool (such as a pen) using a mechanical device (i.e. an end-effector-type haptic device). In the case that the device can ‘mimic’ a VR object, the user can interact directly with the VR object without the mechanical constraint of a device (i.e. an encounter-type haptic device). A new challenge of an encounter-type haptic device is displaying the visuals and haptic information simultaneously on a single device. We are proposing a new desk-top encounter-type haptic device with an actively driven pen-tablet LCD panel. The proposed device is capable of providing pseudo-3D visuals and haptic information on a single device. As the result, the system provides to the user a sense of interaction with a real object. To develop a proof-of-concept prototype, a compact parallel mechanism was developed and implemented. The aim of this research is to propose a new concept in haptic research. In this paper, the concept, the prototype, and some preliminary evaluation tests with the proposed system are presented. 相似文献
79.
Hideki. Sano 《International journal of systems science》2013,44(3):205-214
An H ∞, control problem with measurement feedback.for infinite-dimensional discrete-time (IDDT) systems whose homogeneous parts are described by Riesz-spectra operators is considered. The aim is to construct a finite-dimensional stabilizing controller for the IDDT system that makes the H ∞ norm of the closed-loop transfer function less than a given positive number δ. For that purpose, we first formulate the IDDT system as an IDDT system in l2 and derive a finite-dimensional reduced-order system for the IDDT system in l2. A stabilizing controller that makes the H ∞ norm of the closed-loop transfer function less than another positive number is then constructed for the reduced-order model. The finite-dimensional controller together with a residual mode Jilter plays a role of a finite-dimensional stabilizing controller that makes the H ∞ norm of the closed-loop transfer function less than δ for the original IDDT system, if the order of the residual mode filter is chosen suficiently large. 相似文献
80.
Nobuyuki Sano 《Journal of Computational Electronics》2011,10(1-2):98-103
Monte Carlo simulations coupled self-consistently with the three-dimensional Poisson equation are carried out under the double-gate MOSFET structures. The Coulomb force experienced by an electron inside the device is directly evaluated by performing the Monte Carlo simulations with or without the full Coulomb interaction and the Coulomb force on the channel electron corresponding to plasmon excitations is clarified. It is pointed out that the consistency of the boundary condition is achieved only if the long-range Coulomb interaction is properly taken into account, and this is crucial for predicting reliable device characteristics in ultra-small devices. The drain current and transconductance are greatly reduced if the self-consistent potential fluctuations are taken into account. 相似文献