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31.
Compression-after-impact (CAI) tests have been conducted for quasi-isotropic thick plates with 48 plies by using the NASA method and on plates with 32 plies by using the SACMA method. Specimens are made of CF/PEEK (APC-2) and conventional CF/epoxy for the NASA plates and CF/epoxy for the SACMA plates. In the NASA CAI tests, the sequence of delamination buckling and its propagation is clearly revealed through various experimental techniques. One major technique is moiré topography, and the other is thermo-mechanical stress analysis with a high-accuracy infrared sensor. The arrest of delamination propagation just before catastrophic failure due to high fracture toughness is clearly captured by the moiré camera. This behavior provides good CAI values of CF/PEEK. The initial buckling properties of the delaminated region by the impact are then extensively discussed. Numerical predictions of initial buckling stress have been obtained by modelled geometry of the delaminated region simplified from its precise structure clarified by ultrasonic C-scanning. They agree fairly well with the experimental results. The in-plane stress distribution in the delaminated region before initial buckling is measured by an infrared stress graphic system. This compared favorably with finite element predictions. Two types of symmetric buckling modes with respect to the central plate surface, twin and single peak ones, are experimentally captured.  相似文献   
32.
Three photoconductive diamond detectors with highly oriented diamond (HOD) films fabricated by the same process were characterized with respect to temporal response, spectral responsivity and its spatial uniformity over the wavelength range from 190 to 250 nm. Temporal measurements showed a drift in the baseline, suggesting the presence of deep level carrier traps. The responsivity of specimen No. 2 was more than twice those of the other two specimens, but it showed an unpredictable current fluctuation. It was found that the spatial uniformities of all the specimens were too low for radiometric purposes. A prominent peak, thought to be due to photoemission, was found in the responsivity spatial distribution of specimen No. 3 under a negative applied voltage.  相似文献   
33.
Spreading depression (SD) is known to be involved in the N-methyl-D-aspartate receptor-mediated neuronal damage. In urethane-anesthetized rats, we examined the release of adenosine and glutamate during SD induced by microdialysis of high K+ perfusate through the hippocampal CA1 area. The effects of endogenous adenosine upon SD were studied by applying an adenosine antagonist, theophylline (1 mM) and by a simultaneous application of adenosine uptake blockers, dipyridamole (DPR) (100 microM) and nitrobenzylthioinosine (NBI) (50 microM). The dialysates were sampled every 5 or 10 min and analyzed by HPLC. SD was identified by flattening of background EEg and disappearance of population spikes recorded from the pyramidal cell layer of CA1 area by a glass microelectrode. Adenosine and glutamate release was enhanced significantly in association with the occurrence of SD. Theophylline increased the release of glutamate and the incidence of SD and decreased the latency of the SD occurrence. DPR+NBI decreased the release of glutamate and the occurrence of SD, but increased extracellular adenosine concentration. The effects of DPR+NBI were blocked by application of a selective antagonist of adenosine A1 receptor, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 0.1 microM). These findings suggest that endogenous adenosine exerts inhibitory influences upon the development of SD and the glutamate release through the A1 receptor in rat hippocampus.  相似文献   
34.
Discusses 2 interrelated traditions as they are reflected in contemporary and traditional approaches to psychotherapy in Japan. One uses various meditational and self-focusing instructional sets whose common goal is to facilitate the slowing down, deepening, and clearer focusing of sensory and interpersonal awareness. The 2nd tradition focuses on physical self-regulation and autonomic self-control through exercises that foster enhanced voluntary control over physical states and processes. Eastern psychology offers a set of practices that help the individual overcome the inherent selfishness of his/her isolated experience. The goals of such work include recognition of gratitude to important people in the client's life, rediscovery of the joy of meaningful work, and the experience of a unifying cosmic consciousness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
A series of Mo–TiC alloys were heated in vacuum at 2473 K for 36 ks. First grain growth behavior was observed using a scanning electron microscope. Then effects of TiC addition on the strengths and ductility at low temperature were discussed from the viewpoints of chemical composition and grain structure.

Materials with TiC additions of not larger than 0.1% demonstrated a single-crystalline grain structure. Both yield and maximum strengths increased by TiC addition and consequently ductility was improved.  相似文献   

36.
Electric power systems are expanding in size and complexity, and the requirement for the energy management system (EMS) is becoming more important. In this computer control system, a single control computer is used mainly as the primary computer and its software is very complicated because of its hugh number of small, quick tasks to obtain high response speed. Therefore, much effort is needed to develop and modify the programs, and the responsiveness of this centralized architecture varies greatly when many faults occur in the power system. This paper describes a new distributed architecture for the EMS. Distributed processors execute the functions cooperatively with periodic access to the common bulletin board database in which information about the power system exist. This architecture facilitates the software development and maintenance, and it also enhances the performance by the parallel processing of the distributed functions.  相似文献   
37.
Temperature dependences of the soft phonon frequency and the damping constant in Tris-Sarcosine Calcium Chloride (TSCC) single crystal have been investigated between 5K and 100K by using a Fourier-transform far-infrared spectrometer. It has been observed that the soft phonon frequency decreases gradually and the damping constant increases as the transition temperature is approached from below The damping constant varies from 7cm-1 a 90K to less than 0.5cm-1 at 5K. It has been found that the damping constant is approximately proportional to temperature below about 60K.  相似文献   
38.
One of the most important issues in avoiding a global water crisis is to solve the confrontation between developed and developing countries. As Japan in the 20th century has experienced the shift from a developing country to a developed country, it should candidly share its precious historical experience, both its merits and demerits, with people throughout Monsoon Asia. Two practical proposals to economize water demand are as follows: to economize toilet water in a way that meets the conditions of each region; and to develop the effective utilization of water for irrigated rice paddies, not only in the Monsoon Asia but throughout the world. In short, new life-styles are necessary if the global water crisis is to be averted.  相似文献   
39.
40.
When a fault occurs on transmission or distribution systems due to lightning or overvoltage, often an arc discharge occurs at the fault point. The arc discharge, which is caused by a fault current, has a high current, high temperature, strong light emission, etc., thus it sometimes causes heavy damages to electric power equipment. The arc discharge is influenced by the conditions around the arcs, i.e., gas, insulation materials, gap length, weather, etc. Also, the arc voltage along the arc column indicates the characteristics of the arc. If the voltage waveforms of the arcs caused by the fault on transmission or distribution systems are classified, it is possible to find the location and the equipment where the fault occurred. In this paper, the arc voltage data in 6-kV class XLPE cables and 6-kV class overhead lines are analyzed and an artificial neural network method is applied to classify the arc voltage waveforms. The results obtained from the six artificial neural networks developed show that the artificial neural network method is effective for classification of arc voltage waveforms if adequate input parameters are selected.  相似文献   
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