An acoustic and aerodynamic study of stops in tonal and non-tonal dialects of Korean

ABSTRACT This study investigates the acoustic and aerodynamic properties of well&ndashknown three&ndashway distinction of Korean voiceless stops in two dialects, which differ in their tonal systems: non&ndashtonal Seoul Korean (standard Korean) and tonal South Kyungsang Korean (spoken in Southern part of Korea). Several issues are addressed in the current study: (i) the acoustic cues (e.g. VOT, f0, H1&ndashH2) that each dialect mainly uses to distinguish the three Korean stops, (ii) the effect of f0 as a function of distinguishing three stop categories and as a function of distinguishing the High vs. Low tonal contrasts in the tonal South Kyungsang dialect, (iii) dialectal variation in aerodynamic area (e.g., oral airflow, oral air pressure) as well as acoustic area. These issues are examined with 16 Korean speakers, eight Seoul Korean and eight South Kyungsang Korean speakers. Along with the results replicating previous findings, the experimental results report several noteworthy new findings. First, the acoustic and aerodynamic pattern differently in the two dialects; Seoul speakers primarily use f0 as an acoustic cue for three laryngeal gestures of Korean stops, while South Kyungsang speakers are more likely to use VOT as a main acoustic cue. Second, the use of tonal contrasts to distinguish High vs. Low tone for South Kyungsang speakers makes f0 an unreliable acoustic cue for the three Korean stops. Third, the dialectal differences on VOT to mark the three laryngeal distinctions support the notion of the diachronic transition that the VOT difference between the lenis and aspirated stops is decreasing over the past 50 years. Finally, the results of aerodynamic study make it possible to postulate the articulatory state. Hence, based on the acoustic and aerodynamic results, this study suggests the possible phonological representations in the two dialects which differ in their tonal systems

Evidence of diachronic sound change: A comparative acoustic study of Seoul and Kyungsang Korean

The phonetics and phonology of the Kyungsang dialect of Korean is distinct from those of the standard Seoul dialect with regard to segments and lexical pitch. However, whether the distinctive phonetics and phonology of Kyungsang Korean are maintained by younger speakers is questionable due to the increased exposure to Seoul Korean and the prevailing linguistic ideology that has lent Seoul Korean a strong normative bias. The current dissertation investigated diachronic sound change in Kyungsang Korean based on the acoustic data collected from forty female Korean speakers (10 younger and 10 older speakers each for Kyungsang and Seoul). Acoustic evidence for sound change is provided by showing generational differences in the phonetics of Kyungsang Korean, and comparison of the phonetics between Kyungsang and Seoul Korean addressed how a prestigious national standard language affects dialect re–formation. In the acoustic study of vowels (Chapter 2), measures of formant frequencies showed that the merged /ʌ/ and /ɨ/ vowels for older Kyungsang speakers are split among younger speakers, resulting in the same vowel system between younger Kyungsang and Seoul speakers both of which have seven vowels. The study of stop consonants (Chapter 3) showed generational differences for the measures of VOT and F0 in distinguishing the three–way laryngeal contrast among voiceless stops for Kyungsang speakers. Younger Kyungsang speakers rely more on F0, but less on VOT to distinguish the stops than older speakers do. The increased role of F0 to the laryngeal contrast for the younger Kyungsang speakers corresponds with the diachronic change in Seoul Korean where the role of VOT is reduced, but that of F0 is increased for younger Seoul speakers. In the acoustic study of fricative (Chapter 4), measures of fricative duration and center of gravity showed that while the two–way fricative contrast is less distinct for older Kyungsang speakers, younger Kyungsang speakers well distinguish the two fricatives similar to Seoul speakers. As a consequence of the generational change in the segments of Kyungsang Korean, younger Kyungsang speakers do not maintain the vowel and consonant features unique to Kyungsang Korean, but rather approximate to those of Seoul Korean. The current dissertation showed evidence for the diachronic sound change in the lexical pitch accent of Kyungsang Korean for both surface and underlying forms (Chapters 5 and 6). F0 spectral and temporal properties characterizing contrastive lexical accents are less distinct for younger Kyungsang speakers than for older speakers. Notably, F0 peak shifted rightwards for younger Kyungsang speakers across all accent classes, resulting in the final rising accent pattern similar to Seoul Korean. The generational difference in the lexical accents of Kyungsang Korean was also observed for underlying forms (Chapter 6). Elicited accent patterns for monosyllabic and disyllabic nouns under suffixation showed that the accent system of younger Kyungsang speakers is simpler than that of older speakers and similar to that of Seoul speakers, which results from accent merger, loss of suffix tone, and weakened accent contrasts. The direction of the sound change observed in the current dissertation suggested that the phonetics and phonology of Kyungsang Korean is re–formed to approximate Seoul Korean

The role of recasts in the interactions of native-speakers of English with Korean English language learners

This study partially replicates that of Braidi (2002). Like the original, it investigates occurrences and use of recasts, that is, reformulations of incorrect utterances, in relation to the number of grammatical errors in conversations of NSEs (Native Speakers of English) and NNSEs (Nonnative Speakers of English) and examines whether different types of tasks can affect the occurrences and use of recasts. In contrast to many previous studies, I examine here the occurrences of recasts in non-instructional interactions between NSEs and NNSEs.;Five dyads of American teaching assistants and Korean graduate students at Iowa State University participated in performing two different types of tasks, a picture description and a spot-the-difference task. Their performances were audio/video recorded and transcribed with Transana 2.0, a transcription software program.;For data analysis, frequency of recasts was counted and NNSE responses to recasts were also counted, according to the classification of Braidi (2002) and a chi-square test and a Fisher\u27s exact test were used to find statistical significance. The results showed similarities to those of Braidi\u27s (2002) study in that recasts occurred less than non-recasts in the frequencies of recasts predicted by the level of grammaticality. However, in contrast to Braidi\u27s result showing a significant relationship between the level of grammaticality and occurrences of recasts, this study showed non-significant relationship between them. Furthermore, it appears that task types did not affect the occurrence of recasts. However, the study reveals considerable variation between dyads regarding both the occurrences of recasts and NNSE responses to recasts

Effects of tone on the three-way laryngeal distinction in Korean: An acoustic and aerodynamic comparison of the Seoul and South Kyungsang dialects

This is the publisher's version, made available with the permission of the publisher.The three-way laryngeal distinction among voiceless Korean stops has been well documented for the Seoul dialect. The present study compares the acoustic and aerodynamic properties of this stop series between two dialects, non-tonal Seoul and tonal South Kyungsang Korean. Sixteen male Korean speakers (eight from Seoul and eight from Kyungsang) participated. Measures collected included VOT, f0 at vowel onset, H1-H2, and air pressure and airflow. The presence versus absence of lexical pitch accent affects both the acoustic and aerodynamic properties. First, Seoul speakers use a combination of f0 and VOT to distinguish the three-way contrast of Korean stops, while Kyungsang speakers mainly use VOT. Second, the presence of lexical pitch for Kyungsang speakers makes f0 an unreliable acoustic cue for the three Korean stops. Third, dialectal differences in VOT to mark the three-way distinction support the notion of a diachronic transition whereby VOT differences between the lenis and aspirated stops in Seoul Korean have been decreasing over the past 50 years. Finally, the aerodynamic results make it possible to postulate the articulatory state of the glottis, indicating a positive correlation with acoustic parameters. Based on the acoustic and aerodynamic results, phonological representations of Korean stops for the tonal and non-tonal dialects are suggested

Case of chronic indolent pheochromocytoma that caused medically controlled hypertension but treatment-resistant diabetes mellitus

No abstract available

The Effect Of Internal Control Weakness On Investment Efficiency

This paper examines whether material weakness in internal accounting control is negatively associated with investment efficiency in Korea. Since internal accounting control weakness drives poor accounting quality and poor accounting quality exacerbates information asymmetry between firms and outside capital suppliers, managerial investment cannot be monitored effectively which result in over- and/or under- investment. Since internal accounting system is closely related to corporate governance, weak internal accounting control is often associated with poor corporate governance, and this control environment makes it hard to monitor managerial opportunistic behavior, causing abnormal investment such as over- and/or under- investment.  We find that firms with internal accounting control weakness tend to make over- and under- investment. We also find the number of weakness in internal accounting control is negatively related to investment efficiency. In addition, three types of qualified review opinion - overall company level weakness, account-specific weakness and disclaimer review opinion due to scope limitation - are differentially affected to investment efficiency; disclaimer review opinion is present the most severe problem in internal accounting control that drives over- and under- investment. Our findings suggest weak internal accounting control provides poor monitoring to manager and cannot restrain managerial inefficient investment decision.

Nutrient Removal in Constructed Wetlands Treating Agricultural Tile Drainage

Agricultural runoff can carry substantial loadings of nitrogen and phosphorus that can impact local surface water quality and contribute to impairment of water bodies further downstream. Subsurface tile drainage, a drainage water management practice commonly used in the Midwest, is known to contribute to elevated levels of these contaminants. Strategies to improve drainage water quality must be implemented in a way that minimally impacts land utilization and crop yield. In this study, three constructed wetlands were utilized to treat runoff from tile outlet terrace (TOT) agricultural fields managed under either a no-till corn-soybean rotation with wheat prior to soybean, or a no-till soybean crop. Nutrient and sediment removal efficiencies and runoff impact on receiving streams were determined during two growing seasons in 2014 and 2015. Water samples were collected with an auto-sampler at the wetland influent and effluent locations at Harvest Hills North (HHN/site 1), Harvest Hills Middle (HHM/site2), and Dan Cain site (Cain/site3). Using stream bottles, samples were also collected from two local streams that receive TOT runoff during and after storm events. Over the two years, changes in nutrient and sediment loads to the wetlands were observed. Runoff quality was affected by changes in crop type, fertilizer application rate, and precipitation pattern, frequency and intensity. During the two growing seasons, TOT runoff was responsible for 99.5, 71.2 and 197.7 kg of TN entering the wetlands at sites 1, 2 and 3, respectively, of which 67.7, 59.3 and 93.8 kg exited the system in the wetland effluent (32, 17 and 53% load removal). For TP, approximately 16.54, 8.75 and 45.18 kg entered the wetlands, of which 10.24, 5.25 and 19.67 kg exited (38, 40 and 56% removal). For total suspended solids (TSS), roughly 14793, 4023 and 64624 kg entered, of which 4824, 1748 and 10876 kg exited (67, 57 and 83% removal). Compared to the year with soybean crop coverage (2014) at the sites with a no-till corn-soybean rotation (sites 1 and 2), higher sediment concentration in TOT runoff was observed at the site with a no-till soybean crop both years (site3). The wetlands’ performance was typically better with higher influent concentrations, although the wetland design and inflow volume also seemed to contribute as well. Variations in behavior between two similar wetlands (sites 1 and 2) were likely due to differences in seepage rates and flow distribution through the wetlands, which is believed to have changed as sediments built up near the influent discharge pipe at site 1. Stream monitoring results showed that median concentrations of TN and TP were higher than the benchmark values for streams in U.S. EPA Region 7, with no measureable impact from either the treated (wetland effluent) or the untreated runoff. Potential reasons for why no significant impact to stream quality was observed are the relatively low volume of discharge relative to stream flow, and the relatively high stream levels of nutrients and sediments even upstream of the discharge location

Speakers of tonal and non-tonal Korean dialects use different cue weightings in the perception of the three-way laryngeal stop contrast

The current study investigated the perception of the three-way distinction among Korean voiceless stops in non-tonal Seoul and tonal Kyungsang Korean. The question addressed is whether listeners from these two dialects differ in the way they perceive the three stops. Forty-two Korean listeners (21 each from Seoul and South Kyungsang) were tested in a perception experiment with stimuli in which VOT and F0 were systematically manipulated. Analyses of the perceptual identification functions show that VOT and F0 cues trade off each other for the perception of the three stops. However, the trading relationship differs between the two dialects. Logistic regression analyses confirmed the two dialects use the perceptual cues differently for the lenis and aspirated stops. While Seoul listeners rely primarily on F0 for making lenis responses and on VOT and F0 for aspirated responses, F0 plays a less important role in modulating both lenis and aspirated responses for Kyungsang than for Seoul listeners. It is proposed that different tonal systems between the two dialects and the ongoing diachronic sound change in the stops of Seoul Korean contribute to the inter-dialect difference in cue weighting for the three-way stop distinction. The results suggest that although the difference in phonology between the two dialects influences the phonetic realization, the phonetic trade-off among multiple cues allows each dialect to maintain the phonemic distinction in a unique way