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Consider a two-stage non-cooperative Cournot game with location choice involving n≥ 2 firms each with several facilities. There are m≥ 2 spatially separated markets constituting the vertices of a network. Each firm first selects the locations of their facilities and then selects the quantities to supply to the markets to maximize its profit. There exists a Nash equilibrium in the quantities offered by each firm at the markets. Furthermore, when the demand in each market is sufficiently large, each firm chooses to locate its facilities only at vertices. With linear demand in each market, there exists a Nash location equilibrium. 相似文献
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Deep core beliefs represent an important yet theoretically underspecified concept within the Advocacy Coalition Framework (ACF). This underspecification can (in part) be attributed to the ad hoc way in which ACF scholars have defined and measured the concept over time. To overcome this, we advocate the development and future use of a standardized metric for measuring deep core beliefs in ACF studies. Such a measure, we contend, should be multidimensional, generalizable, measurable using multiple techniques, and broad enough in scope to operate across virtually all policy domains. Using these criteria as our benchmark, we evaluate the viability of cultural theory (CT) as one such metric. In short, we find that CT meets all of these criteria, and therefore provides ACF scholars with a way to measure deep core beliefs across enduring public policy disputes that are demarcated by conflicting belief systems. Accordingly, we advocate its use in future studies. 相似文献
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This article deals with the finite element analysis of dam with and without fluid-structure, soil-structure and soil-structure-fluid interaction. A two-dimensional direct coupling methodology is proposed to obtain the response of dam-reservoir-foundation system considering fluid-structure and soil-structure interaction simultaneously. The displacement based finite element technique is used to formulate the dam and foundation. The reservoir is modeled by pressure based finite element to reduce the degree of freedoms and there by the computational cost. The responses of dam, reservoir, and foundation with and without fluid-structure, soil-structure and soil-structure-fluid interaction are compared to study the influence of reservoir and soil foundation on the behavior of these respective sub systems. The fundamental frequency of individual sub system decreases with the consideration of coupling effect among these sub systems. On the comparison of the responses of dam, it is observed that the displacement and principal stresses are increased if the effect of reservoir and foundation are considered and the worst responses were observed when both the fluid-structure and soil-structure interaction effects are considered simultaneously. The magnitude and distribution of stresses within the foundation change with the consideration of soil-structure-fluid interaction. Similar to wstresses in the foundation, the hydrodynamic pressure within the reservoir also gets magnified due to interaction effects. The velocity distribution within the reservoir becomes distorted when the fluid-structure and soil-structure-fluid interaction are considered. 相似文献
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Plagioclase feldspar is the major luminescent mineral in meteorites. Thermoluminescence (TL) characteristics, peak temperature (Tm), full width at half maximum (FWHM), ratio of high (HT) to low temperature (LT) peak, and TL sensitivity (TL/dose/mass) to an extent reflect degree of crystallinity of the mineral. The present study explores and establishes a correlation between quantum mechanical anomalous (athermal) fading and structural state by examining TL of individual chondrules. Chondrules were separated using freeze-thaw technique from a single fragment of Dhajala meteorite. The results show large variation in Tm (155?230°C), FWHM (80?210°C) and HT/LT (0.07–0.47) and seem to be positively correlated. TL sensitivity (ranging from 14 to 554 counts/s/Gy/mg) decreases with increasing Tm and FWHM. Large variations in TL parameters (Tm, FWHM, HT/LT, and Sensitivty) suggest that individual chondrules had different degree of crystallization. Thermal annealing experiments suggest that comparatively ordered form of feldspar can be converted to a disordered form by annealing the sample at high temperatures (1000°C) for long time (10 hr) in vacuum (1 mbar pressure) condition and rapidly cooling it. Measured anomalous fading suggest that fading rate increases as the crystal form changes from an ordered state to a disordered state. However, the fading rate becomes nearly negligible for the most disordered feldspars. 相似文献
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Anuj Soni Devesh R. Mishra Bhuwan C. Bhatt Shiv K. Gupta Narendra S. Rawat Mukund S. Kulkarni Devanand N. Sharma 《Geochronometria》2013,40(4):258-265
The influence of electron-phonon interaction on the shape of the optically stimulated luminescence decay curve of Al2O3:C has been studied using thermally assisted optically stimulated luminescence (TA-OSL). The minimum detectable dose (MDD) of a phosphor depends on the standard deviation of the background signal which affects the signal-to-noise ratio. The standard deviation of the background signal reduces at lower stimulation light intensity while the readout time increases. Further, measurement at higher temperature enhances the OSL signal with faster decay due to the temperature dependence of photo-ionization cross-section. To achieve the same decay constant and more signal, the temperature of measurement was raised. As a result of lowering the stimulation in-tensity at higher temperature (85°C) the overall MDD of α-Al2O3:C was found to improve by 1.8 times. For extension of dose linearity in higher range, deeper traps were studied by simultaneous application of CW-OSL and thermal stimulation up to 400°C, using a linear heating rate of 4K/s. By using this method, two well defined peaks at 121°C and 232°C were observed. These TA-OSL peaks have been correlated with two deeper defects which can be thermally bleached at 650°C and 900°C respectively. These deeper defects are stable up to 500°C, so they can store absorbed dose information even if the sample is inadvertently exposed to light or heat. The dose vs. TA-OSL response from deep traps of α-Al2O3:C was found to be linear up to 10 kGy, thus extending its application for high dose dosimetry. 相似文献