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本文整理出巴米扬山谷遗址群的年代学证据,旨在重现大佛的历史与图像地位。首先介绍了巴米扬山谷遗址群的研究方法和年代阶段,接着讨论玄奘所见所录的大佛的原始配置,最后将三尊佛像放入其原始的图像志语境中去考查,认为涅檗像原应位于38米大佛和55米大佛之间。后者为宝装焰肩佛,其神格应为燃灯佛;38米大佛为释迦佛。而巡礼者所遵循的应是燃灯佛-释迦佛-涅粲佛-弥勒佛的绕拜顺序。  相似文献   
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The problem of valid measurement of psychological constructs remains an impediment to scientific progress, and the measurement of executive functions is not an exception. This study examined the statistical and theoretical derivation of a behavioral screener for the estimation of executive functions in children from the well-established Behavior Assessment System for Children (BASC). The original national standardization sample of the BASC–Teacher Rating Scales for children ages 6 through 11 was used (N = 2,165). Moderate-to-high internal consistency was obtained within each factor (.80–.89). A panel of experts was used for content validity examination. A confirmatory factor analysis model with 25 items loading on 4 latent factors (behavioral control, emotional control, attentional control, and problem solving) was developed, and its statistical properties were examined. The multidimensional model demonstrated adequate fit, and it was deemed invariant after configural, metric, and scalar measurement invariance tests across sex and age. Given its strong psychometric properties, with further tests of item validity, this instrument promises future clinical and research utility for the screening of executive functions in school-age children. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Although the behavioral component was an integral part of the original formulation of the third-person effect hypothesis, little research has examined the impact of biased media effect perceptions on behaviors that assume others have already been affected. The present study examines how third-person perceptions (the belief that other people are particularly vulnerable to media messages) contributed to intentions to prepare for problems stemming from Y2K, also known as the "millennium bug." Analyses using data from 2 regional probability samples taken in late 1999 show that perceptions about the potential effects of news messages influenced public anxiety about the Y2K situation and beliefs that other people would overprepare for the new year. These 2 variables, in turn, predicted intentions to stockpile supplies of food, water, gasoline, and cash. The article discusses the implications of these findings for understanding the relationship between perceptions of media effects and an extended range of behaviors.  相似文献   
5.
A dynamic packet reservation multiple access scheme for wireless ATM   总被引:3,自引:0,他引:3  
The dynamic packet reservation multiple access (DPRMA) scheme, a medium access control protocol for wireless multimedia applications, is proposed and investigated. DPRMA allows the integration of multiple traffic types through a single access control mechanism that permits users to specify their immediate bandwidth requirements. The primary feature of DPRMA is the dynamic matching of the traffic source generation rates with the assigned portion of the channel capacity. This is accomplished by a control algorithm that regulates the actual amount of channel capacity assigned to users. To support multimedia communication, channel capacity assignments are prioritized by traffic type. The performance of the scheme is evaluated and the scheme is shown to perform well in a system with voice, video conferencing, and data users present. It is also shown to provide improved performance over a system with a modified version of the packet reservation multiple access (PRMA) scheme. Furthermore, several system parameters are studied and optimized.  相似文献   
6.
In this paper a number of new channel-routing algorithms are presented. the routing strategy is based on parallel bubble-sorting and river-routing techniques. an important concept introduced is the POTENTIAL function, which serves as a measure of the degree of difficulty of a particular channel-routing problem. Both non-Manhattan wires and overlapping wires are used. Although the methods are initially derived for two-layer routing with two-terminal nets only, extensions to multiterminal nets and three-layer routing have been made. Preliminary results indicate that in many instances the new algorithm outperforms the traditional approaches.  相似文献   
7.
Since the price of Arabica is currently more than twice higher than Robusta, a rapid and reliable method for the determination of the roasted coffee blend composition is fundamental for the authentication of commercial blends used for the Italian Espresso coffee. A GC-FID method based on the ratio between the integrated peak areas of kahweol (K) divided by the sum of K and 16-O-methylcafestol (16MCF) was developed. No internal/external standard was used. Moreover, the quantitation of the unsaponifiable compounds is not necessary, as well as the calculation of any response factors. The percentage of Robusta in 34 samples of coffee blends with known composition, and in 48 samples of pure varieties was used to build a cubic polynomial function with R(2)=0.998. The roasting conditions did not affect the results. Considering eight commercial blends (ranging 0-90% Robusta), no significant difference (two-tailed P=0.817) was registered between the claimed and the predicted composition.  相似文献   
8.
Corn grits that were supplemented with isovaleraldehyde, ethyl butyrate, butyric acid and flavour enhancers were extruded under different processing conditions. Volatile compounds retained in the extrudates were isolated by dynamic headspace and analysed using gas chromatography–mass spectrometry. The expansion ratio, density and cut force to break down the extrudates were evaluated and aroma intensity was assessed using a multisample difference test. Butyric acid showed the greatest retention (96.4%), regardless of the extrusion conditions. All compounds were better retained when samples were extruded at 20% feed moisture and 90 °C processing temperature (2.9–81.0%), conditions that also resulted in greater aromatic intensity (moderate to moderate‐strong intensity). The addition of volatile compounds reduced the expansion ratio and cut force, whereas the addition of flavour enhancers increased the expansion ratio but reduced ethyl butyrate and butyric acid retention.  相似文献   
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Alcohol-free beer with isotonic properties is getting more popular and its production can be carried out by different production strategies; however, interrupted fermentation is still a challenge. Therefore, the objective of this study was to develop a low-alcohol isotonic beer (<0.5% v/v) by interrupted fermentation. Moreover, the major objective is to compare the developed product to commercial beverages (sports drinks, ‘Pilsen' regular beer, alcohol-free beers and low-alcohol isotonic beer). The beverages were evaluated based on pH, alcohol content (% v/v), total titratable acidity (mEq L−1), osmolality (mOsmol kg−1), bitterness International Bitterness Units, colour European Brewery Convention, total phenolic compounds (mg L−1 gallic acid), reducing and total sugars (%) and Na and K contents (mg L−1). The developed low-alcohol isotonic beer presented characteristics similar to sports drinks, with the advantage of being richer in phenolic compounds and suitable osmolality. Despite salts were added in its formulation, the grades attributed to all beers employed in the sensory evaluation, as well as the purchase intention did not present significant differences.  相似文献   
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