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931.
资产证券化凭借其独特的交易机制,已经成为发达国家资本市场的主流融资手段,更是全球领域最重要的金融创新之一。它不但为市场机制作用的发挥奠定了基础,而且充分体现了金融市场一体化的客观要求。信息化条件下,资产证券化快速渗透到社会经济领域的各个层面,对经济运行效率能够产生深远的影响。 相似文献
932.
文章从联通运营商WLAN业务发展的现状出发,对WLAN建设过程中存在的问题进行详细的分析和研究,根据原因提出有效的建设策略,并对3G网络的融合进行全面的阐述。 相似文献
933.
The absolute free energy difference of binding (ΔG) between neuraminidase and its inhibitor was evaluated using fast pulling of ligand (FPL) method over steered molecular dynamics (SMD) simulations. The metric was computed through linear interaction approximation. Binding nature was described by free energy differences of electrostatic and van der Waals (vdW) interactions. The finding indicates that vdW metric is dominant over electrostatics in binding process. The computed values are in good agreement with experimental data with a correlation coefficient of R = 0.82 and error of σΔGexp = 2.2 kcal/mol. The results were observed using Amber99SB-ILDN force field in comparison with CHARMM27 and GROMOS96 43a1 force fields. Obtained results may stimulate the search for an Influenza therapy. 相似文献
934.
Many large retailers decided to adopt RFID as their new supply chain technology, but RFID adoption by all industries did not spread as rapidly as initially expected. We believe that its benefits constituted the major barrier to its adoption, and argued that a major contributor to the delay has been its inappropriate implementation. Our study reports the result of six in-depth case studies, which, together with case content analysis of 88 reported RFID applications, provided us with a clear view of the RFID implementation landscape, suggesting that organizations often mindlessly adopted RFID applications that were misaligned with their supply chain strategies, leading to unsatisfactory benefits. Insights into how organizations should adopt RFID were developed from our results and were discussed. 相似文献
935.
Crises are common in today's unpredictable environment rising the importance of crisis response strategies. Two societies in Europe are chosen: Finland, where trust in society is generalized to institutions, and Spain, where trust in society remains on the level of individuals. Using the results of the European Communication Monitor 2013 survey on crisis communication, we explored three hypotheses: “certain types of crises are often met with certain types of strategies,” “cultural context makes some crises more likely than others,” and “cultural context makes some response strategies more likely than others.” We find evidence for all three hypotheses and discuss our findings about perceived differences in the two societies. The results show that the cultural context plays an important role for crisis communication. 相似文献
936.
《Ergonomics》2012,55(8):1139-1153
A laboratory study was conducted to determine one-handed dynamic and static pulling strengths of 50 males and 49 females from 14 to 71 years of age. The dynamic strength for a 11m pull was measured to simulate the act of starting a lawn mower engine for four different starting-rope handle locations: on the engine, in the middle, on the right and on the left side of the frame. The last three were located at the back of the lawn mower at a vertical height of 63 cm from the floor and the handle on the engine was located at 42 cm. Static strength was measured for the handle in the middle. Ratings of perceived exertion were recorded for different body parts. Peak and average dynamic pulling strengths were 55% and 34% of static pulling strengths. Dynamic pulling strengths were highly correlated with peak velocity (r = 0·84). Men in the age group 21-34 years had the highest strength and women in the age group 51-71 years the least strength. Dynamic pulling strengths for women were 62% of strengths for men. Women took 10% longer to pull, had a lower peak velocity (16%), reached peak force faster (17%) and took a longer time (6%) to reach peak velocity than men. The starting handle located on the engine resulted in the maximum pulling strength and on the left side in the minimum strength. However, two out of three subjects preferred the handle either on the right side or in the middle. Fifty-five percent of the subjects indicated they would prefer a height higher than 63 cm. Maximum stresses were perceived on the shoulder and upper arm with a mean rating between fairly light and somewhat hard. Graphs of cumulative frequency distributions of average and peak dynamic pulling strengths are presented to aid in the determining forces required to start a lawn mower engine in order to satisfy a desired percentage of the population. 相似文献
937.
I. González A. Ramiro M. Calderón A.J. Calderón J.F. González 《International Journal of Hydrogen Energy》2012
In hybrid renewable energy systems, batteries act as a DC bus to provide constant voltage and to smooth out commutations between the generating devices. These batteries are usually of a lead-acid type and operate under harsh variable conditions due to fluctuations of both solar radiation and wind speed. Precise knowledge of the state-of-charge of the batteries, and hence of their available energy, play a key role in effecting efficient control and energy management of the installation. The present study had a twofold aim. One objective was to adjust and validate a method based on coulomb counting to estimate the state-of-charge (SOC) of a gelled lead-acid battery which is the DC bus of a hybrid wind-solar system with hydrogen storage. Other works evaluate SOC models based on several parameters, however, the present proposal based on experimental measurements involves only a few parameters. The second objective was to modify the installation's control algorithm to use the battery's calculated SOC as control parameter instead of its voltage. The results of a test-bed system, showing how the system evolved under real operating conditions, constitute a proof-of-concept of the validity of the method. 相似文献
938.
This paper presents a new prospective metric for assessing the novelty and inventiveness of patents. It does this by using initial patent search reports and examiner's intuition about the impact of adverse citations on patent claim survival. The paper then demonstrates the metric by evaluating the quality of Switzerland's national patent stock using a selection model, finding that between 84 and 90% of the country's national patents would likely not survive examination at the European Patent Office. In doing so, it contributes to the larger literature on patent assessment, underscores the relevance of patent strategy in the observed characteristics of patents, and removes some of the ambiguity in the academic literature about backward citations. 相似文献
939.
We study a duopoly market in which customers are heterogeneous, and can be segmented as price or time sensitive. Each firm tailors (differentiates) its products/services for the two customer classes solely based on guaranteed lead time and the corresponding price. Our objective is to understand how competition affects price and lead time differentiation of the firms in the presence of different operations strategy (shared versus dedicated capacity), product substitution and asymmetry between the competing firms. Our results suggest that when firms use dedicated resources to serve the two market segments, pure price competition always tends to decrease individual prices as well as price differentiation, irrespective of the market behaviour. Further, the effect of competition is more pronounced when customers are allowed to self-select, thereby introducing substitutability between the two product options. On the other hand, when firms compete in time, in addition to price, the effect of competition on product differentiation depends crucially on the behaviour of the market. Our results further suggest that the firm with a larger market base should always maintain a larger price and lead time differentiation between the two market segments. Similarly, the firm with a capacity cost advantage should also maintain a larger lead time differentiation. 相似文献
940.