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151.
This paper discusses a fundamental problem in natural language generation: how to organize the content of a text in a coherent and natural way. In this research, we set out to determine the semantic content and the rhetorical structure of texts and to develop heuristics to perform this process automatically within a text generation framework. The study was performed on a specific language and textual genre: French instructional texts. From a corpus analysis of these texts, we determined nine senses typically communicated in instructional texts and seven rhetorical relations used to present these senses. From this analysis, we then developed a set of presentation heuristics that determine how the senses to be communicated should be organized rhetorically in order to create a coherent and natural text. The heuristics are based on five types of constraints: conceptual, semantic, rhetorical, pragmatic, and intentional constraints. To verify the heuristics, we developed the spin natural language generation system, which performs all steps of text generation but focuses on the determination of the content and the rhetorical structure of the text. 相似文献
152.
Abstract. Two procedures are described for obtaining Fisher's information matrix of a multiplicative seasonal autoregressive-moving average process. They can be useful in determining the asymptotic covariance matrix of Gaussian maximum likelihood estimators of the parameters. Components of the information matrix are expressed in the first procedure as integrals of rational functions. The second procedure makes use of the autocorrelation function of several autoregressive processes. 相似文献
153.
In this paper we consider three standard batch arrival/service systems and develop renewal process approximations for the inter-departure time squared coefficient of variations. The systems considered are: (i) batch arrival with individual service; (ii) batching for setup reduction for a single server system; and (iii) batch processing. The random version of the batch arrival with individual service case naturally results from random branching of individuals following a batch service process. This case is also developed with the intent of improving the modeling results for downstream workstations following a batch service process. 相似文献
154.
The rate equations of a semiconductor laser with external optical feedback are solved numerically. The method is applied to the case of simple optical feedback and to that of a high finesse external resonator. The spectral linewidth reduction, the damping of the relaxation oscillations and the influence of the resonant frequencies of the external resonator are discussed and compared for these two configurations. 相似文献
155.
Keith A. Scudamore Robin C. E. Guy Brian Kelleher Susan J. MacDonald 《Food Additives & Contaminants》2008,25(3):331-337
In the European Union, deoxynivalenol in cereals and cereal products is controlled by recent legislation with the objective of minimizing consumer exposure to this mycotoxin. Relatively few studies have examined the loss of Fusarium mycotoxins during processing and whether this is accurately reflected by the processing factors. The behaviour of deoxynivalenol, nivalenol and zearalenone during extrusion of naturally contaminated wholemeal wheat flour has been examined using pilot-scale equipment. Factors examined were temperature and moisture content. Concentrations of the three mycotoxins were little changed by extrusion although the amount of deoxynivalenol decreased at the lowest moisture content. However, this effect did not appear to be temperature-dependent, suggesting that the apparent loss is either due to binding or inability to extract the residue. Under some conditions, concentrations of the mycotoxins, particularly nivalenol, were higher after extrusion. 相似文献
156.
The wind energy market is in full growth in Quebec but technical difficulties due to cold climate conditions have occurred for most of the existing projects. Thus, icing simulations were carried out on a 0.2 m NACA 63 415 blade profile in the refrigerated wind tunnel of the Anti‐icing Materials International Laboratory (AMIL). The shapes and masses of the ice deposits were measured, as well as the lift and drag forces of the iced profiles. Scaling was carried out based on the 1.8 MW–Vestas V80 wind turbine technical data, for three different radial positions and two in‐fog icing conditions measured at the Murdochville wind farm in the Gaspé Peninsula. For both icing events, the mass of ice accumulated on the blade profile increased with an increase in the radial position. In wet regime testing (first icing event), glaze formed mostly near the leading edge and on the pressure side. It also accumulated by run‐off on the trailing edge of the outer half of the blade. In dry‐regime testing (second icing event), rime mostly accreted on the leading edge and formed horns. For both icing events, when glaze or rime accreted on the blade profile, lift decreased and drag increased. A load calculation using the blade element theory shows that drag force on the entire blade becomes too large compared to lift, leading to a negative torque and the stop of the wind turbine. Torque reduction is more significant on the outer third of the blade. Setting up a de‐icing system only on the outer part of the blade would enable significant decrease of heating energy costs. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
157.
There is increasing interest in understanding how office accommodation affects organizational productivity. Data on metrics of engagement, job satisfaction, job performance and facility complaints for thousands of employees (n?=?14,569) of a large Canadian financial organization were analysed to explore differences in outcomes between those working in green-certified office buildings (n?=?10) and those in otherwise similar conventional buildings (n?=?10). Overall, green-certified buildings demonstrated higher scores on survey outcomes related to job satisfaction, value to clients and stakeholders, evaluation of management, and corporate engagement. There was also a tendency for manager-assessed job performance to be higher in green-certified buildings. Nevertheless, not all green-certified buildings outperformed all conventional buildings, and superior performance was not exhibited on all outcomes examined. A key observation is that such metrics are routinely recorded by organizations, but relating them to building characteristics is new. Recognition of such datasets opens up many promising avenues for buildings research. 相似文献
158.
159.
正当一家领先的沥青拌和设备制造商宣称自己率先推出一套沥青再生设备时,另一家制造商已在东欧部分地区大获成功。As t e c工业集团正继续保持其创新纪录,宣称是唯一能够生产100%使用RAP(沥青回收料)的沥青拌和设备制造商。随着C o n e x p o 2014展上发布的R A P K I N G拌和设备纳入产品家族,A s t e c声称现在能够生产0%-10 0% 相似文献
160.
Zhidong Xu Kevin Harvey Thomas Pavlina Guy Dutot Gary Zaloga Rafat Siddiqui 《Lipids》2010,45(2):199-208
The existing protocols for analyzing fatty acid methyl esters (FAMEs) using a one-step acetyl chloride (AC) catalyzed transesterification and extraction procedure cannot accurately determine the medium- and long-chain fatty acids simultaneously in clinical (enteral, parenteral) formulations. For example: (1) addition of AC at room temperature generates an exothermic reaction that often results in loss of sample and possible injury to the analyst; (2) certain polyunsaturated fatty acids (PUFAs) are less stable at elevated temperatures during the transesterification and contribute to the over-estimation of the C16:0 and C18:1 fatty acids; and (3) the flame-ionization detector (FID) response varies depending on the carbon chain length of the fatty acids, that consequently impacts the underestimation of medium-chain fatty acid (C6–C10) recoveries. To overcome these deficiencies and accurately determine FAMEs, we have developed an improved one-step transesterification method that employs the addition of AC in tubes kept on a dry ice bath, the transesterification at room temperature, and the data analysis using relative response factors. Using this modified protocol, we determined the fatty acid composition of lipid emulsions (Omegaven® and Lipidem®) on a Shimadzu GC2010 gas chromatography (GC) system using a capillary GC column (Zebron ZB-WAX plus, 30 m, 0.25 mm ID, 0.25 μm). Our data suggest that the improved method can be easily used to accurately determine fatty acids (C6–C24) in functional foods and lipid emulsions. 相似文献