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To generate a proper Korean predicate, a natural modal expression is the most important factor for a machine translation (MT) system. Tense, aspect, mood, negation, and voice are the major constituents related to modal expression. The linguistic encoding of a modal expression is quite different between Chinese and Korean in terms of linguistic typology and genealogy. In this paper, a new applicable categorization of Korean modality system viz. tense, aspect, mood, negation, and voice, will be proposed through a contrastive analysis of Chinese and Korean from the viewpoint of a practical MT system. In order to precisely determine the modal expression, effective feature selection frameworks for Chinese are presented with a variety of machine learning methods. As a result, our proposed approach achieved an accuracy of 83.10%. [ABSTRACT FROM AUTHOR]

The last decade has seen several aspect language proposals for UML 2 sequence diagrams. Aspects allow the modeler to define crosscutting concerns of sequence diagrams and to have these woven with the sequence diagrams of a so-called base model, in order to create a woven model. In a real-world scenario, there may be multiple aspects applicable to the same base model. This raises the need to analyse the set of aspects to identify possible aspect interactions (dependencies and conflicts) between applications of aspects. We call a set of aspects terminating if they may not be applied infinitely many times for any given base model. Furthermore, we call a set of terminating aspects confluent, if they, for any given base model, always yield the same final result regardless of the order in which they are applied. Since confluence must hold for any base model, this is a much stronger result than many of the current approaches that have addressed detection of aspect interactions limited to a specific base model. Our aspects are specified using standard sequence diagrams with some extensions. In this paper, we present a confluence theory specialized for our highly expressive aspect language. For the most expressive aspects, we prove that confluence is undecidable. For another class of aspects with considerable expressiveness, we prescribe an algorithm to check confluence. This algorithm is based on what we call an extended critical pair analysis. These results are useful both for modelers and researchers working with sequence diagram aspects and for researchers wanting to establish a confluence theory for other aspect-oriented modelling or model transformation approaches. [ABSTRACT FROM AUTHOR]

Slope and aspect derived from digital elevation models are important variables used regularly in geographical information systems for modelling purposes. Digital elevation models (DEMs) have become a very common and widely used source for creating slope and aspect map surfaces. However, quite often these map surfaces are created and used without due consideration being given to the accuracy of the DEMs and the algorithms used to derive slope and aspect surfaces. The purpose of this paper is to show the flaws in some of the algorithms used to generate aspect and slope information from gridded digital elevation models and to make users aware of problems or errors that may be encountered. The research shows that the precision to which elevation values are stored in a DEM strongly influences the derived products of aspect and, to a lesser extent, slope. [ABSTRACT FROM PUBLISHER]

Abstract: Aspect-oriented software design will need to support languages with first-class and higher-order procedures, such as Ruby, Perl, ML and Scheme. These language features present both challenges and benefits for aspects. On the one hand, they force the designer to carefully address issues of scope that do not arise in first-order languages. On the other hand, these distinctions of scope make it possible to define a much richer variety of policies than first-order aspect languages permit. In this paper, we describe the subtleties of pointcuts and advice for higher-order languages, particularly Scheme. We then resolve these subtleties by alluding to traditional notions of scope. In particular, programmers can now define both dynamic aspects traditional to aop and static aspects that can capture common security-control paradigms. We provide an operational semantics, based on an extended ceks machine, that gives a formal account of dynamic and static aspects. We implement the language as an extension to Scheme. By exploiting two novel features of our Scheme system—continuation marks and language-defining macros—the implementation is lightweight and integrates well into the programmer’s toolkit. [Copyright &y& Elsevier]

One of the obvious sources of errors in digital terrain analysis (DTA) algorithms is that introduced by raster data structure employed by a digital elevation model (DEM). Because of its regular sample space and orientation, the DTA results often show significant octant ‘bias’, presenting obvious visual and numerical error patterns. Moreover, other DEM data properties may also introduce errors in slope and aspect computation, such as data precision and spatial resolution (i.e. grid interval). This paper reports an investigation on the accuracy of algorithms that derive slope and aspect measures from grid DEM. A quantitative methodology has been developed for objective and data-independent assessment of errors generated from the algorithms that extract surface morphological parameters such as slope and aspect from grid DEM.The generic approach is to use artificial surfaces that can be described by a mathematical model, thus the ‘true’ output value can be pre-determined to avoid uncertainty caused by uncontrollable data errors. Two mathematical surfaces were generated based on ellipsoid (representing convex slopes) and Gauss synthetic surface (representing complex slopes), and the theoretical ‘true’ value of the slope and aspect at any given point on the surfaces could be computed using mathematical inference. Based on these models, tests were made on the results from a number of algorithms for slope and aspect computation. Analysis has been undertaken to find out the spatial and statistical patterns of error distribution so that the influence of data precision, grid resolution, grid orientation and surface complexity can be quantified. [Copyright &y& Elsevier]