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11.
Text planning is traditionally done as a separate process, independent of linguistic realization. However, I show in this paper that it is essential for a text planner to know the linguistic consequences of its actions. The choice of how to realize an element affects how much information is conveyed (e.g., “Floyd arrived safely in Boston” vs. “Floyd landed safely at Logan”) and what other information can be added (e.g., “Peter was deciding for an hour” vs. *“Peter made a decision for an hour”). The choice of realization also affects how the relative salience of the elements being expressed will be perceived (e.g., “The green car is in the garage” vs. “The car in the garage is green”). I have defined an intermediate level of representation for text planning, called the Text Structure. It is an abstract linguistic level that reflects germane linguistic constraints while abstracting away from syntactic detail. This representation allows the text planner to have greater control over the decisions, so that it can take advantage of the expressiveness of language to convey subtleties of meaning. More importantly, the Text Structure allows the generation process overall to be incremental, since it ensures that the text plan being composed will always be expressible in the language. La planification de textes est habituellement réalisée séparément, sans tenir compte de la réalisation linguistique. Cependant, ľauteur demontre dans cet article qu'il est essentiel à un planificateur de textes de connai̊tre les conséquences linguistiques de ses actions. Le choix de la méhode de réalisation ?un élément influe sur la quantité?informations qui est transmise (par ex.: 〈〈 Floyd est arrivé sain et sauf à Boston 〉〉 et 〈〈 Floyd a atterri sain et sauf àľaéroport Logan 〉〉) et sur quelle autre information peut ětre ajoutée. Le choix de la méthode de réalisation influe également sur la façon dont les caractères saillants des ééments qui sont exprimés seront perçus (par ex.: 〈〈 la voiture verte est dans le garage 〉〉 et 〈〈 la voiture dans le garage est verte 〉〉). L'auteur a défini un niveau intérmediaire de représentation pour la planification de textes qu'il a appelé structure de texte. Il; s'agit ?'un niveau linguistique abstrait qui refléte les contraintes linguistiques appropriées tout en s'éloignant du détail syntaxique. Cette représentation permet au planificateur de textes ?avoir un meilleur contrǒle des décisions, et done de tirer profit de la force ?expression du langage afin de tenir compte des subtiliés de sens. Plus important encore, la structure de texte permet au processus de génération ?ětre incrémentiel, car elle s'assure que le plan de texte en voie de composition soit toujours exprimable dans le langage.  相似文献   
12.
Classical hierarchical routing in telephone networks is extended to a wider class called out-of-chain routing in such a way that some useful properties of hierarchical routing are retained. This new routing pattern offers more potential paths than the fixed hierarchical one and can be introduced as a dynamic routing where the fixed alternate sequences change at some predetermined instants during the day. The effect of this new routing pattern on the network performances is examined. The main topic of this paper is to present heuristic methods used to optimise such routings in large networks. We show on artificial networks that the throughput of a given network can be significantly improved by suitable routing choices. We demonstrate that the integration of routing changes within a multihour dimensioning process is possible but the lack of realistic data does not permit at this time to quantify the value of routing optimization on real networks.  相似文献   
13.
The authors report results of a study into the role of components of first-language (L1; Dutch) and second-language (L2; English) reading comprehension. Differences in the contributions of components of L1 and L2 reading comprehension are analyzed, in particular processing speed in L1 and L2. Findings indicate that regression weights of the L1 and L2 components are different. Although correlations between most processing speed components and reading comprehension are substantial, there are no unique contributions to the explanation of either L1 or L2 reading comprehension when linguistic and metacognitive knowledge are accounted for. In addition, L1 reading comprehension is shown to have a large contribution to L2 reading comprehension, supporting theories of L1-L2 transfer of reading skills. Results are discussed from a developmental perspective. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
Twenty-eight experienced handlers, considered the best in two transport companies, were interviewed using a questionnaire consisting of partially closed-ended questions. They had to assess 20 videotape handling sequences showing two different handling methods to determine, for 10 factors and overall, which one was the best. They were asked about the inportance of these factors in their choices of the best method. The aims of the study were to verify whether there was a consensus among experienced handlers as to what was a good handling method and to identify the factors taken into consideration by them. Results show the lack of consensus on the best methods. Handlers favor different strategies depending on the worjk context and their own priorities.  相似文献   
15.
The effect and possible interactive influence of different dietary amounts of wheat bran, fat and calcium on the fecal excretion, concentration and composition of bile acids was studied in Fischer-344 rats. The fecal bile acids were analyzed using gas-liquid chromatography. Dietary wheat bran increased both total bile acid excretion and fecal weight without changes in fecal bile acid concentration. The proportion of fecal hyodeoxycholic acid decreased with increasing dietary fiber, whereas that of lithocholic and deoxycholic acids increased significantly with fiber intake. The percent content of fecal chenodeoxycholic acid did not change. Increasing dietary fat led to an increase in bile acid excretion without changes in either fecal weight or bile acid concentration. In contrast, the level of dietary calcium did not affect the total excretion of bile acids. However, since calcium increased the fecal weight, it consequently diluted bile acids and decreased their fecal concentration. Dietary fat and calcium had no influence on fecal bile acid composition. There were no interactive effects of wheat bran, fat and calcium on fecal bile acids. The finding in this study that dietary fiber, fat and calcium induce significant changes in fecal bile acids may be of relevance to the potential of bile acids to promote carcinogenesis.  相似文献   
16.
A group's staffing level can play an important role in its socialization practices. For example, a group that is understaffed should be more open than an overstaffed group to both prospective and new members. To test this prediction, the leaders of nearly 100 student groups on a college campus were interviewed. These interviews yielded qualitative and quantitative data about the staffing levels in the groups and the methods that they used for recruiting prospective members and assimilating new ones. Analyses of the qualitative data clarified issues such as when understaffing and overstaffing are likely to occur, what kinds of problems they produce in groups, and how groups try to solve those problems. Analyses of the quantitative data revealed that our prediction was correct: As their staffing levels decrease, most groups become more open to prospective and new members. Implications of the results are discussed, and some suggestions for future research are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
17.
This study examines the extent to which variations in consumers' sensory assessments of food arise from the inability to report accurately sensory perceptions, from confusion regarding the criteria by which to assess samples, or from differences in their oral breakdown of the products.

Twenty consumers assessed the tenderness of a range of 8 hot, freshly roasted meat samples using Time Intensity (TI). Overall a significant correlation was found between the maximum recorded intensity (Imax) of their TI curves and single sensory scores given by a trained panel. Correlation was significant for only 42% of the consumers individually. Significant correlations were found between the amount of masticatory muscle activity undertaken during chewing (measured using electromyography) and Imax for all but 2 of the consumers. Thus subjects' perceptions were accurately described by their chewing work, suggesting between subject differences in perception arose from differences in the way chewing work was applied to break down the samples. The sensory input from the masticatory muscles may represent the major determinant of perceived tenderness of meat.  相似文献   

18.
19.
Technology-assisted instruction has potential for helping students improve their reading skills. In the current studies, PowerPoint software was used to supplement teacher-led reading instruction for elementary-aged students with disabilities who struggled with phoneme blending to read words. The effectiveness of the intervention was assessed using two multiple probe design studies across sets of words based on an onset-rime (word family) strategy. In Study 1, teacher-led instruction was paired with technology-assisted instruction for all intervention sessions for three students in first and second grade. In Study 2, teacher-led instruction occurred between baseline and technology-assisted intervention sessions for three students in third and fourth grade. During the initial instruction sessions, participants recorded their own voices onto PowerPoint slides so that their technology-assisted instruction included self-modelling. Results of both studies indicated that technology-assisted instruction can be effective for helping students learn how to blend phonemes to read words; however, performance varied and there were limitations in each study that should be addressed in future research. Relevant implications for classroom instruction are emphasized.  相似文献   
20.
This paper proposes a method for designing robust H?? static output feedback stabilization of Takagi-Sugeno (T-S) fuzzy systems under actuator saturation. In this paper, the input saturation is represented by a polytopic model and the modeling error is assumed a norm-bounded uncertainty. A set invariance condition for robust H?? static output feedback system under actuator saturation is first established. Then, the estimation of the largest domain of attraction for the system is formulated and solved as a Linear Matrix Inequality (LMI) optimization problem. Two examples are used to demonstrate the effectiveness of the proposed design method.  相似文献   
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