The Perceptual Effect of L1 Prosody Transplantation on L2 Speech: The Case of French Accented German

Research has shown that language learners are not only challenged by segmental differences between their native language (L1) and the second language (L2). They also have problems with the correct production of suprasegmental structures, like phone/syllable duration and the realization of pitch. These difficulties often lead to a perceptible foreign accent. This study investigates the influence of prosody transplantation on foreign accent ratings. Syllable duration and pitch contour were transferred from utterances of a male and female German native speaker to utterances of ten French native speakers speaking German. Acoustic measurements show that French learners spoke with a significantly lower speaking rate. As expected, results of a perception experiment judging the accentedness of 1) German native utterances, 2) unmanipulated and 3) manipulated utterances of French learners of German suggest that the transplantation of the prosodic features syllable duration and pitch leads to a decrease in accentedness rating. These findings confirm results found in similar studies investigating prosody transplantation with different L1 and L2 and provide a beneficial technique for (computer-assisted) pronunciation training

Computer-aided position planning of miniplates to treat facial bone defects

In this contribution, a software system for computer-aided position planning of miniplates to treat facial bone defects is proposed. The intra-operatively used bone plates have to be passively adapted on the underlying bone contours for adequate bone fragment stabilization. However, this procedure can lead to frequent intra-operatively performed material readjustments especially in complex surgical cases. Our approach is able to fit a selection of common implant models on the surgeon's desired position in a 3D computer model. This happens with respect to the surrounding anatomical structures, always including the possibility of adjusting both the direction and the position of the used osteosynthesis material. By using the proposed software, surgeons are able to pre-plan the out coming implant in its form and morphology with the aid of a computer-visualized model within a few minutes. Further, the resulting model can be stored in STL file format, the commonly used format for 3D printing. Using this technology, surgeons are able to print the virtual generated implant, or create an individually designed bending tool. This method leads to adapted osteosynthesis materials according to the surrounding anatomy and requires further a minimum amount of money and time.Comment: 19 pages, 13 Figures, 2 Table

Methods of investigating vowel interferences of French learners of German

International audienceThe French and German vowel inventories [Fougeron & Fougeron, 1999, Kohler, 1999] show many similarities, for instance, both have a series of front rounded vowels. Contrary to German, French has no vowel length contrast. Although specialized teaching materials for German consider the problem of vowel length/tenseness (e.g. [Hirschfeld, 2014; Hirschfeld et al., 2007]), it is still unclear how frequently vowel errors occur in L2 speech and which pairs of long-tense and short-lax vowels create the most serious difficulties for French learners of German. We present three methods to analyze the interference processes occurring in read speech of French learners of German (60 sentences, 50 subjects). First, we analyzed phone confusion matrices based on hand-labeled data. The most frequent confusions appear for two long-tense/short-lax distinctions. Second, in a perception study, German native speakers listened to words belonging to minimal pairs like Miete - Mitte ('rent-middle') differing in length/tenseness. Results indicate that, overall, short vowels were identified correctly less often (64\%) than long vowels (77\%), but with great inter-individual differences. Although most problems occur in the beginner group, every second advanced learner shows for short vowels an identification rate lower than chance, which means they were perceived as long by German native listeners.Finally, acoustic measurements of the minimal pair words revealed very different strategies: some speakers show a general tendency to lengthen and other speakers to shorten vowels.The results of these three investigations help to create a more detailed account of the transfer of vowel contrasts, extending prior research on vowel perception [Kingston, 2003; Flege & MacKay, 2004], with orthography as a possible source of interference. Furthermore, the results of the studies can be used to create individualized training and feedback for foreign language learners

Methods of investigating vowel interferences of French learners of German

International audienceThe French and German vowel inventories [Fougeron & Fougeron, 1999, Kohler, 1999] show many similarities, for instance, both have a series of front rounded vowels. Contrary to German, French has no vowel length contrast. Although specialized teaching materials for German consider the problem of vowel length/tenseness (e.g. [Hirschfeld, 2014; Hirschfeld et al., 2007]), it is still unclear how frequently vowel errors occur in L2 speech and which pairs of long-tense and short-lax vowels create the most serious difficulties for French learners of German. We present three methods to analyze the interference processes occurring in read speech of French learners of German (60 sentences, 50 subjects). First, we analyzed phone confusion matrices based on hand-labeled data. The most frequent confusions appear for two long-tense/short-lax distinctions. Second, in a perception study, German native speakers listened to words belonging to minimal pairs like Miete - Mitte ('rent-middle') differing in length/tenseness. Results indicate that, overall, short vowels were identified correctly less often (64\%) than long vowels (77\%), but with great inter-individual differences. Although most problems occur in the beginner group, every second advanced learner shows for short vowels an identification rate lower than chance, which means they were perceived as long by German native listeners.Finally, acoustic measurements of the minimal pair words revealed very different strategies: some speakers show a general tendency to lengthen and other speakers to shorten vowels.The results of these three investigations help to create a more detailed account of the transfer of vowel contrasts, extending prior research on vowel perception [Kingston, 2003; Flege & MacKay, 2004], with orthography as a possible source of interference. Furthermore, the results of the studies can be used to create individualized training and feedback for foreign language learners

Analysis of phone confusion matrices in a manually annotated French-German learner corpus

International audienceThis paper presents an analysis of the non-native and native pronunciations observed in a phonetically annotated bilingual French-German corpus. After a forced-choice automatic annotation a large part of the corpus was checked and corrected manually on the phone level which allows a detailed comparison of the realized sounds with the expected sounds. The analysis is reported in terms of phone confusion matrices for selected error-prone classes of sounds. It revealed that German learners of French have most problems with obstruents in word-final position whereas French learners of German show complex interferences with the vowel contrasts for length and quality. Finally, the correct pronunciation rate of the sounds, for several phonetic classes, is analyzed with respect to the learner's level, and compared to native pronunciations. One outcome is that different sound classes show different correct rates over the proficiency levels. For the German data the frequently occurring syllabic [=n] is a prime indicator of the proficiency level