iii Transfer Sample Clauses

iii Transfer. The third approach to machine translation is transfer, which is favoured in most current systems. The transfer module maps one language-specific representation of meaning onto another, as shown in Figure 4 analysis source language representation transfer target language representation synthesis transfer rules target language dictionaries and grammars source language dictionaries and grammars source language – target language dictionary target language text source language text Figure 4 - Transfer machine translation Rather than two stages via a single, highly abstract interlingual representation, there are three stages involving underlying syntactic representations for both the source and target language texts. The first stage converts the source language into ‘deep’ intermediate representations, in which ambiguities have been resolved without reference to the target language. In the second stage, these are converted into equivalent ‘deep’ representations in the target language. The final target language text is then generated. In transfer systems, analysis and generation programs are independent and are specific for particular languages. There may also be separate components to handle lexical transfer (selection of vocabulary equivalents) and structural transfer (transformation of source-text structures to equivalent structures in the target text). Differences between languages are dealt with by the intermediary transfer program. There are many operational examples of transfer-based machine translation systems, including Systran, Tstream (based on former Metal system) and Logos. Until recently, the transfer approach is the most commonly used in current commercial systems, as it can be easier to implement than an interlingual system and can be derived from direct systems by augmenting the dictionaries and grammars. The interlingual approach requires complete resolution of all ambiguities and anomalies in the source text; in the transfer method, only those ambiguities inherent in the particular language need to be resolved. Both interlingual and transfer-based systems are more modular than the older direct approach, so system components can be adapted and changed independently of each other.