• MALSORI
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• no.29_30
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• pp.19-42
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• 1995

This paper deals with the current phonological theory named the elementary theory Before manipulating this theory with highest depth, we need to discuss the distinctive feature theory which can be estimated as playing a central role in the standard generative trends. En the element-based phonological theory, the followings might act as tile main traits in differentiating it from other theories: the notion of phonological opposition is regarded as privative one, treating the univalent element as an analysing unit in a phonological process instead of distinctive features, and the nile convention in standard theory is replaced by the element. In chapter 2, a brief history of generative theory is to be described with respect to the merits and demerits of the distinctive feature theory. In chapter 3, After dealing with the current tendency and some prominent aspects of each element theory, a couple of problems thought to be confronted by the distinctive feature theory And the analysing method taken from the element-based theory which may be regarded currently as the alternative to the problems mentioned above will be discussed mainly, The government-based theory introduced by KLV(1985, 1988) may be the main target in discussing the current topic.

• MALSORI
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• no.29_30
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• pp.43-60
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• 1995

Standard generative phonologists assumed that there were no orders or hierarchies among distinctive features. This means that the distinctive features which make up a segment are independent and unordered. The unordered linear matrix cannot explain phonological phenomena such as complex segments as hierarchical representation does neatly. The hierarchical feature representation theory which embodies the concept of multi-tiered phonological representation organizes distinctive features in the appearance of hierarchical dominance. This paper aims to show how we can solve some problems of the linear feature representation. As regard underlying representation the theory of underspecification is discussed. I propose a feature hierarchy similar to that of Sagey(1986) but slightly different. I show English consonantal assimilation in feature hierarchical model compared with that of feature changing theory of linear representation.

• MALSORI
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• no.33_34
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• pp.71-89
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• 1997

In the framework of linear representation which allows for no internal structure within features, there is no way to represent nonlinear phonological phenomena such as complex segments. This paper shows how we carl solve some problems of the linear feature theory in relation to the hierarchical feature theory. The purpose of this paper is to explain lateral assimilation under hierarchical feature representation. Although arguments for the position of classes of distinctive features have been made the position of (lateral) remains the issue of debate. Sagey(1988) argues that the feature [lateral] is structurally dependent on the root node. In contrast Rice & Avery (1991) put the feature (lated) under the spontaneous voicing. I have discussed previous studies of feature hierarchy and I propose a revised model of feature representation. Within this model I have shown how well feature geometry describes lateralization as feature spreading.

• ETRI Journal
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• v.29 no.3
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• pp.292-299
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• 2007

In this paper, we present a speech recognition system using a throat microphone. The use of this kind of microphone minimizes the impact of environmental noise. Due to the absence of high frequencies and the partial loss of formant frequencies, previous systems using throat microphones have shown a lower recognition rate than systems which use standard microphones. To develop a high performance automatic speech recognition (ASR) system using only a throat microphone, we propose two methods. First, based on Korean phonological feature theory and a detailed throat signal analysis, we show that it is possible to develop an ASR system using only a throat microphone, and propose conditions of the feature extraction algorithm. Second, we optimize the zero-crossing with peak amplitude (ZCPA) algorithm to guarantee the high performance of the ASR system using only a throat microphone. For ZCPA optimization, we propose an intensification of the formant frequencies and a selection of cochlear filters. Experimental results show that this system yields a performance improvement of about 4% and a reduction in time complexity of 25% when compared to the performance of a standard ZCPA algorithm on throat microphone signals.

• Journal of KIISE:Software and Applications
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• v.34 no.3
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• pp.226-234
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• 2007

In this paper, we develop a speech recognition system using a throat microphone. The use of this kind of microphone minimizes the impact of environmental noise. However, because of the absence of high frequencies and the partially loss of formant frequencies, previous systems developed with those devices have shown a lower recognition rate than systems which use standard microphone signals. This problem has led to researchers using throat microphone signals as supplementary data sources supporting standard microphone signals. In this paper, we present a high performance ASR system which we developed using only a throat microphone by taking advantage of Korean Phonological Feature Theory and a detailed throat signal analysis. Analyzing the spectrum and the result of FFT of the throat microphone signal, we find that the conventional MFCC feature vector that uses a critical pass filter does not characterize the throat microphone signals well. We also describe the conditions of the feature extraction algorithm which make it best suited for throat microphone signal analysis. The conditions involve (1) a sensitive band-pass filter and (2) use of feature vector which is suitable for voice/non-voice classification. We experimentally show that the ZCPA algorithm designed to meet these conditions improves the recognizer's performance by approximately 16%. And we find that an additional noise-canceling algorithm such as RAST A results in 2% more performance improvement.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.365-365
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• 2000

English segments adopted into Korean can be divided into three types: Some English segments /$m, {\;}n, {\;}{\eta}, {\;}p^h, {\;}t^h, {\;}k^h$/ are adopted into the original sound [$m, {\;}n, {\;}{\eta}, {\;}p^h, {\;}t^h, {\;}k^h$] in Korean. Other segments /b, d, g/ appear in the voiceless stop form [p, t, k]. Generative Phonology explains the presence of the above English segments in Korean but it cannot explain why the English segments /$f, {\;}v, {\;}{\Theta}, {\;}{\breve{z}}, {\;}{\breve{c}}, {\;}{\breve{j}}$/ disappear during the adopting process. I present a set of universal constraints from the Optimality Theory proposed by Prince and Smolensky(l993) and I show how English segments differently adopted into Korean can be explained by these universal constraints such as Faith(feature). N oAffricateStop, Faith(nasal), NoNasalStop, Faith(voice), NoVoicedStop and the interaction of these constraints. I conclude that this Optimality Theory provides insights that better capture the nature of the phonological phenomena of English segments in Korean.