• Journal of the Korean Solar Energy Society
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• v.23 no.4
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• pp.1-9
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• 2003

In this study, a manufacturing process for PV module has been developed using an automatic arraying equipment. It is expected that this process could improve the productivity and curtail the production cost in the photovoltaic module production line. From the results, it is proved that this process reduces Line-stop and enhances the productivity more than 15% a day which can be related directly to the production line cost.

• Journal of Biosystems Engineering
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• v.36 no.6
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• pp.416-421
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• 2011

This study was initiated to prevent rear-end collision which causes the most frequent human damage by agricultural tractors. Therefore, this study was aimed to evaluate the luminous performance of a stop lamp for an agricultural tractor which could reduce rear-end collision. The performance test of luminous intensity distribution was conducted for a total of 12 tractor models classified by size (above 44 kW for large, 30~43 kW for medium, and below 29 kW for small) and production area (domestic, foreign manufacture) in accordance with Regulation No.7 of UNECE Vehicle Regulations-1958 Agreement considering ${\pm}$20 standard deviation. Three out of 5 large, 3 out of 4 medium, and all small tractors were resulted as inadequate for the test criterion. This study found that the luminous performance results were better as the size of agricultural tractors became bigger. One out of 4 foreign and 2 out of 8 domestic manufacturers were suitable for the test criterion, and overall no difference from the luminosity test results was observed between domestic and foreign manufacturers. In addition, the measuring points, HV, 5L, 5R, 5U and 5D with the minimal luminosity revealed flaws (80% of the proportion of faulty products). Therefore, it is urgent to improve the quality for measuring points (HV, 5U, 5L, 5R, 5D) of stop lamps to apply Regulation No. 7.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.16 no.1
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• pp.53-67
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• 2005

It is known that Korean stop consonants in syllable-initial position are of three types : lax, aspirated and forced (or unaspirated). In syllable-final position, however, these three different types are merged to a single type with the same place of articulation, although the original three-way distinction is preserved in Korean orthographic (Hangul) system. Thus the syllable-final stops are phonetically realized as voiceless "applosives" which are characterized by the absence of oral release. The aim of the present study is to investigate the laryngeal adjustments for these syllable-final stops in various phonological conditions by using fiberscope, and, is to further investigate electromyographically the laryngeal adjustments for Korean stops both in the syllable-initial and final positions in various phonological conditions. The results can be summarized as follows : 1. In the case of syllable-initial stops, the glottal widths in each three types of the Korean stops during the articulatory closure are clearly different. And the pattern of thyroarytenoid(VOC) activity appeared to characterize the three different types of Korean stops. 2. The basic laryngeal feature of the Korean syllable-final applosives is characterized by a small degree of glottal opening which begins at or slightly after the oral closure. 3. In the case, syllable-final stop followed by the copula "ita", the syllable- final stop is pronounced as the stop consonant at the initial position of the following syllable containing the vowel[i], the underlying features of three-way distinction for the stops in the Korean orthographic(Hangul) system being manifested at the laryngeal adjustment. 4. In the case of the final applosives followed by the initial stops and fricatives, the laryngeal feature of the final applosives appears to be assimilated by that of the following consonant irrespective of the difference in the place of articulation, as far as the glottal abduction/adduction is concerned. It is clearly demonstrated in the case of syllable-initial stop that thyoarytenoid(VOC) activity is suppressed for the production of the stop consonants in question, the degree of which is slightest for the forced type and most marked for the aspirated type, while it is moderate for the lax type.

• MALSORI
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• no.38
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• pp.125-136
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• 1999

This study examined the perception and production of Korean lax, fortis and aspirated stops in three apraxic patients. All of tile subjects made more production errors than perception errors. This indicates that apraxic patients have problems in phonetic execution rather than phonological representation. Additionally, in both production and perception, there were more errors in non-word-initial consonants than in word-initial consonants. These findings contradict those of the previous studies which report more errors in word-initial consonants. This study also found that, unlike previous studies in the types of errors made, distortion errors were high in both non-word-initial and word-initial consonants in apraxic patients. Generally, VOT of the stops showed significant differences among lax, fortis, and aspirated stops, which indicates that there is a failure not in choosing the appropriate stop but in positioning or motor planning at the articulation stage.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.306-311
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• 1992

We propose software algorithms which provide the characteristics of acceleration/deceleration essential to high dynamic performance at the transient state where industrial robots or CNC machine tools start and stop. The path error, which is one of the most significant factors in performance evaluation of industrial robots and CNC machine tools, is analyzed for linear, exponential, and parabolic acceleration/deceleration algorithms in case of circular interpolation. The analysis shows that the path error depends on the acceleration/deceleration routine and the servo control system. In experiments, the entire control algorithm including the proposed acceleration/deceleration algorithms is executed on the motion control system with a floating point digital signal processor(DSP) TMS320C30 as a CPU. The experimental results demonstrate that the proposed algorithms are very effective in controlling axes of motion of industrial robots or CNC machine tools with the desired characteristics.

• SUVANNABHUMI
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• v.14 no.1
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• pp.193-228
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• 2022

This study investigates the production and perception of Vietnamese tones by Japanese, Lao, and Taiwanese second language (L2) learners [n=30], comparing their performance in an Imitation task to that of Identification and Read-Aloud tasks. The results show that the Imitation task is generally easier for L2 speakers than the Identification and Read-Aloud tasks, suggesting that imitation is performed without some of the skills required by the other two tasks. It is also found that Lao and Taiwanese speakers outperform Japanese speakers, suggesting that prior experience with one tone language facilitates the acquisition of tone in another language. The result on speakers' tonal range show that L2 leaners have significantly narrower tonal F0 range than control Vietnamese speakers [n=11]. The results of error pattern analysis and tonal transcription also suggest that non-modal voice (glottal stop and creakiness) and contour tones (bidirectional fall-rise) are more difficult for L2 learners than modal voice tones (e.g., unidirectional contours: rising, falling, and level).

• Phonetics and Speech Sciences
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• v.12 no.4
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• pp.1-8
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• 2020

Traditionally it has been understood that the aspirated and lenis stops in Seoul Korean are distinguished primarily by voice onset time (VOT) and secondarily by other cues such as the fundamental frequency (F0) of the following vowel. However, recent studies on stop production have shown that the aspirated and lenis stops are currently merging in VOT and that they are now differentiated primarily by F0. In the present study, we examined whether the currently reported change in the production domain would be also found in the perception domain. To this end, an auditory identification task was conducted using speech materials of varying VOT and F0 values with young and older male and female Seoul listeners. Results revealed that all listener groups used both VOT and F0 to distinguish the lenis vs. aspirated stops but they used the F0 cue more reliably than the VOT cue in discriminating the stop contrast. The effects of gender and age were found only in the VOT cue (i.e., not in the F0 cue), with the greatest VOT cue weight in older males and the smallest in young females, which is in line with recent production studies.

• Speech Sciences
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• v.13 no.4
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• pp.51-67
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• 2006

This study examined the acoustic properties of initial stops in Korean, produced by Korean native speakers and English Korean learners. The productions of Korean native speakers were compared with those of beginners and advanced learners of Korean. Fundamental frequency(F0) and Voice Onset Time(VOT) were measured in condition of one or two syllable words, containing word-initial lenis, fortis, and aspirated stops. English Korean Learners showed that they produced stops with relatively shorter VOT and lower F0, compared with those of Korean native speakers. In case of the manner of articulation, English Korean learners have production difficulties in order of lenis stops, aspirated stops, and fortis stops. In regard to the place of articulation, English Korean learners showed production troubles in order of labial stops, velar stops, and alveolar stops. In the experiment of perception, it is hard for English Korean learners to distinguish stops of lenis and aspirated. Therefore, the results of production experiment were almost consistent with those of the perception experiment. Finally, according to both groups of proficiency, the results demonstrated that the advanced learners produce or perceive Korean stops easier than the beginners.

• Tuberculosis and Respiratory Diseases
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• v.59 no.5
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• pp.530-535
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• 2005

Background and Aims : Cigarette smoking induces an inflammatory response in the airways, which may play a key role in the pathogenesis of chronic obstructive pulmonary disease. Interleukin-6 (IL-6) is one of the cytokines that plays an important role in inducing bronchial inflammation. The aim of this study was to determine if the level of the pro-inflammatory cytokine, Interleukin-6, is increased when the bronchial epithelial cells are exposed to a cigarette smoke extract (CSE) and an extract from stop smoking-aiding cigarettes, and examined the safety of these commercially available stop smoking-aiding cigarettes. Method : Bronchial epithelial cells were exposed to CSE from cigarette and stop smoking-aiding cigarettes for 24 hours. ELISA was used to measure the IL-6 levels in the supernatant from each condition. The IL-6 mRNA levels were measured by Taqman Real time RT-PCR. N-acetyl-L-cysteine(NAC) was added to each condition to determine if NAC can inhibit the release of IL-6 from the bronchial epithelial cells when they are exposed to CSE from cigarette and stop smoking-aiding cigarettes. Result : When bronchial epithelial cells were exposed to a CSE from cigarettes and stop smoking-aiding cigarettes, each type of CSE stimulated IL-6 production from the bronchial epithelial cells. The IL-6 mRNA level in the Bronchial epithelial cells was also elevated and NAC was found to inhibit the release of IL-6 from bronchial epithelial cells when they were exposed to the CSE from cigarettes and stop smoking-aiding cigarettes. Conclusion : Commercially available stop smoking-aiding cigarette can induce bronchial inflammation and can be harmful to smokers. Therefore, the safety of these cigarettes for smoking cessation should be evaluated.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1483-1490
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• 2011

Electro-hydrostatic actuators(EHAs), which are usually composed of a direct motor-driven hydraulic pump and a cylinder, have been widely adopted as aircraft actuation systems because of their benefits in terms of improved efficiency, weight savings and the fact that they use a standalone power source. Since the recent trend in construction vehicles has been focus on energy savings in their hydraulic systems, EHAs are expected to be potential substitutes for conventional power transmission, since they are capable of energy recovery as well as highly efficient pump control. In this paper, the start and stop characteristics of EHAs were investigated through cracking pressure analysis of the pilot-operated check valve(PCV), which enables the cylinder to standstill against an external load with no holding effort from the hydraulic pump. A mathematical model that includes the load dynamics and the EHA's internal hydraulic circuit was derived for simulation with the MATLAB Simulink package. This model verified the PCV's opening and closing sequence, which in turn affects the EHA's start and stop characteristics.