• Physical Therapy Korea
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• v.22 no.4
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• pp.44-50
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• 2015

This study compared the effects of the initial head position (i.e., a HHP versus a relaxed head position) of subjects with and without a FHP on the thickness of the deep and superficial neck flexor muscles during CCF. The study recruited 6 subjects with a FHP and 10 subjects without a FHP. The subjects performed CCF in two different head positions: a HHP, with the head aligned so that the forehead and chin formed a horizontal line, and a relaxed head position (RHP), with the head aligned in a self-selected comfortable position. During the CCF exercise, the thickness of the longus colli (LCo) and the thickness of the sternocleidomastoid (SCM) were recorded using ultrasonography. The thickness of each muscle was measured by Image J software. The statistical analysis was performed with a two-way mixed-model analysis of variance. The thickness of the SCM differed significantly (p<.05) between the subjects with and without FHP. According to a post $h^{\circ}C$ independent t-test, the change in thickness of the SCM increased significantly during CCF in the subjects with FHP while adopting a HHP compared to that in the subjects without FHP. The change in thickness of the SCM was not significantly different between the two positions in subjects without FHP, and there was no significant change in thickness of the LCo muscle during the CCF exercise according to the initial position in both subjects with and without FHP. The results suggest that CCF should be performed in RHP to minimize contraction of the SCM in subjects with a FHP.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.3
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• pp.141-146
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• 2020

In brushless DC motors (BLDC), the on/off angle of the switch is determined by the optimal alignment of the stator and rotor, while switched reluctance motors (SRM) are complex parameters with many on/off angles of the switch. It appears as a function and therefore the switching angle is variable for optimal operation. Therefore, in order to operate the switched reluctance motor (SRM) optimally, the rotor position can be detected using a high resolution position sensor and a complicated additional circuit. In this paper, rotor position detection and related position detection circuits are applied and detected by using various sensors such as encoder, hall sensor and opto interrupter among several methods to drive switched reluctance motor (SRM). Also a study on securing the initial position of the rotor was conducted.

• The Journal of the Acoustical Society of Korea
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• v.18 no.7
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• pp.85-91
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• 1999

The purpose of this study is to investigate phonetic realization of flap [r], one of the allophones of Korean /l/. Phonetic realization of a segment is affected by not only its neighboring segments but also its prosodic position in an utterance. This study examined how various prosodic positions affect the phonetic realization of [r]. Effects of the four prosodic positions on the phonetic realization of [r] were examined: utterance initial, Intonation Phrase initial, Accentual Phrase initial, and Accentual Medial positions. Word positional effect was also examined: word initial, medial, and final positions. Acoustic and statistical analyses showed that flap [r] was realized in a variety of phonetic forms: from sonorant(the most reduced form) to short stop(the least reduced form). It was shown that generally. word-initial position is stronger than word-medial position. It was also shown that in many cases, utterance-initial position and intonation-phrase-initial position are stronger than accentual-phrase-initial and accentual-phrase-medial positions. Sonorants were observed more often in the prosodically weaker portions. VOT duration was also shorter in accentual-phrase-initial and accentual-phrase-medial positions.

• Proceedings of the IEEK Conference
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• 2000.11d
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• pp.167-170
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• 2000

In this paper, we present a fast algorithm for the motion estimation using the efficient selection of an initial search position. In the method, we select the initial search position using the motion vector from the subsmpled images, the predicted motion vector from the neighbor blocks, and the (0,0) motion vector. While searching the candidate blocks, we use the spiral search pattern with the successive elimination algorithm(SEA) and the partial distortion elimination(PDE). The experiment results show that the complexity of the proposed algorithm is about 2∼3 times faster than the three-step search(TSS) with the PSNR loss of just 0.05［dB］∼0.1［dB］ than the full search algorithm PSNR. The search complexity can be reduced with quite a few PSNR loss by controling the number of the depth in the spiral search pattern.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.1
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• pp.84-89
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• 2005

This paper presents a control algorithm for a large salient-pole synchronous motor fed by a Load Commutated Inverter (LCI). Many papers have been presented in the past few years on the justification, design, and application of variable-speed drive. The focus of this paper is on high torque operation and the estimation of initial rotor position. The results of simulation indicate that it is possible to produce the maximum torque and estimate the initial rotor position.

• Speech Sciences
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• v.3
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• pp.109-117
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• 1998

This paper tests whether the VOT (Voice Onset Time) contributes to the perception of tense and plain stops in Korean in the initial position. Previous studies have yielded opposite results regarding the role of the VOT in the distinction of these two stop categories. One the one hand, Lisker and Abramson (1964), Kim (1965), and Han and Weitzman (1970) suggest that the Korean plain and tense stops exhibit overlapping values of VOT and thus that, unlike many other languages, the VOT fails to serve as a cue to separate these stop categories. On the other hand, Silva (1991, 1992), and Lee (1991, 1994) use similar methods, but find that the VOT serve as the cue. In this study, the differences in the acoustic measurement with respect to the VOT of Korean plain and tense stops in initial prevocalic position will be tested preceptually, in seeking to determine whether these acoustic differences are used by listeners to distinguish these two stop types.

• International Journal of Ocean System Engineering
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• v.1 no.3
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• pp.165-170
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• 2011

In this paper, for the accurate estimation of the position and orientation of the UUV (unmanned underwater vehicle), an AHRS (Attitude Heading Reference System) was developed using the IMU (inertial measurement unit) sensor which provides information on acceleration and orientation in the object coordinate and the initial alignment algorithm and the E-KF (extended Kalman Filter). The initial position and orientation of the UUV are estimated using the initial alignment algorithm with 3-axis acceleration and geomagnetic information of the IMU sensor. The position and orientation of the UUV are estimated using the AHRS composed of 3-axis acceleration, velocity, and geomagnetic information and the E-KF. For the performance test of the orientation estimation of the AHRS, a testbed using IMU sensor(ADIS16405) and DSP28335 coded with an E-KF algorithm was developed and its performance was verified through tests.

• MALSORI
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• no.35_36
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• pp.13-24
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• 1998

This study aims at examining the relationship between tonal events and their related vowel and syllable duration in Korean. Two things were investigated: one is to see if there is a hierarchical relationship in prosodic unit-final-lengthening and the other is to see if accentual phrase initial high tone syllable gets lengthened. Generally, higher prosodic units show larger degree of lengthening of the final vowel and also final syllable duration than the lower ones except for accentual phrase: Mean duration of utterance-final or intonational-phrase-final syllable(and its vowels) was longer than that of accentual-phrase-final or word-final syllable(and its vowels). However, mean duration of accentual phrase final syllable was shorter than that of word final syllable. Mean vowel duration of accentual phrase initial high tone syllable was shorter than that of any other prosodic unit. Its mean syllable duration, however, was longer than that of accentual-phrase-final or word-final syllable, indicating that strong consonants(fortis and aspirated) frequently appear in the accentual phrase initial position and this position is a prosodically strong position showing longer duration as well as high tone.

• Phonetics and Speech Sciences
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• v.6 no.1
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• pp.11-19
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• 2014

The focus of this study was to investigate whether there is a position effect on identification accuracy of L2 consonants by Korean listeners and to examine how Korean listeners perceive the phonetic properties of initial and final consonants produced by a Korean learner of English and an English native speaker. Most studies examining L2 learners' perception of L2 sounds have focused on the segmental level but very few studies have examined the role of prosodic position in L2 learners' perception. In the present study, an identification test was conducted for English consonants /p, t, k, f, ɵ, s, ʃ/ in CVC prosodic structures. The results revealed that Korean listeners identified syllable-initial consonants more accurately than syllable-final consonants. The perceptual accuracy in syllable initial consonants may be attributable to the enhanced phonetic properties in the initial consonants. A significant correlation was found between error rates and F2 onset/offset for stops and fricatives, and between perceptual accuracy and RMS burst energy for stops. However, the identification error patterns were found to be different across consonant types and between the different language speakers. In the final position, Korean listeners had difficulty in identifying /p/, /f/, /ɵ/, and /s/ when they were produced by a Korean speaker and showed more errors in /p/, /t/, /f/, /ɵ/, and /s/ when they were spoken by an English native speaker. Comparing to the perception of English consonants spoken by a Korean speaker, greater error rates and diverse error patterns were found in the perception of consonants produced by an English native speaker. The present study provides the evidence that prosodic position plays a crucial role in the perception of L2 segments.

• Speech Sciences
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• v.8 no.4
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• pp.99-107
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• 2001

The purpose of this study was to investigate the syllable and phoneme frequencies in the spontaneous speech of some Korean children. Sixty four normally developing children aged from 2 to 5 were involved (male: female=1 : 1, 16 children in each age group). Fifty connected utterances were analyzed using the KCLA (Korean Computerized Language Analysis) 2.0 and Exel. The findings were as follows: 1) /i/ was the most frequently used syllable and was followed by /yo/, /k/, /s'/, /nen/ and so on. 2) The most frequently used Korean phonemes were syllable-initial consonant /k/, syllable- medial vowel /a/ and syllable-final consonant /n/. 3) All seven syllable final consonants (/p,t,k,m,n,n,l/) were used more frequently in the word-medial position than in the word-final position. Three syllable initial consonants(/k, I, s'/) were used more frequently in the word-medial position than in the word-initial position. The syllable and phoneme frequencies in the Korean children's spontaneous speech will provide valuable information in interpreting the severity of phonological disorder and in developing tools for the Korean phonological assessment and intervention.