• 한국태양에너지학회 논문집
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• 제23권4호
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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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• 제36권6호
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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.

• 대한후두음성언어의학회지
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• 제16권1호
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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.

• 대한음성학회지:말소리
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• 제38호
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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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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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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.

• 수완나부미
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• 제14권1호
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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).

• 말소리와 음성과학
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• 제12권4호
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• pp.1-8
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• 2020

전통적으로 서울 방언의 어두 평음과 격음은 voice onset time(VOT)에 의해 일차적으로 변별된다고 알려져 있다. 그러나 최근 발화 연구에서는 평음과 격음 간 존재하던 VOT값의 차이가 줄어들고 이차적 변별자질이었던 후행 모음의 fundamental frequency(F0)가 평음과 격음을 변별하는 데 일차적 역할을 수행하게 되는 변화가 관찰되고 있다. 본 연구는 산출 영역에서 관찰되는 이와 같은 변화가 지각 영역에서도 관찰되는 지 알아보고자 하였다. 구체적으로, 평음과 격음을 지각할 때 VOT와 F0 변별력을 알아보기 위해 VOT값과 F0값을 10단계로 조작한 음성 자극을 이용하여 식별 과제를 실시하였다. 청년과 노년 남녀를 대상으로 실험을 실시한 결과, 네 집단 모두에서 VOT와 F0가 평음과 격음을 변별하는 데 사용되지만 VOT에 비해 F0의 변별력이 더 큰 것을 확인하였다. 또한, F0 변별력에서는 성별과 연령에 따른 차이가 없었으나 VOT 변별력은 청년여성 집단이 가장 낮고 노년남성 집단이 가장 큰 양상으로 성별 및 연령에 따른 차이를 관찰할 수 있었다. 본 연구는 그동안 주로 발화 연구에서 보고돼오던 평음과 격음 대립의 VOT 및 F0 사용에서의 변화를 지각 영역으로 확대하여 그 양상을 살펴보았다는 점에서 의의가 있다.

• 음성과학
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• 제13권4호
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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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• 제59권5호
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• pp.530-535
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• 2005

연구 배경 : 우리나라에서는 다른 나라에 비해 약초 등을 이용해 만든 흡연대용품으로 금연을 시도하려는 흡연자들도 많고 이에 따라 여러 가지 다양한 제품 등이 판매되고 있는데 이들의 기관지, 폐에 대한 안정성에 관한 연구는 아직 부족한 상황이다. 특히 흡연자중 일부는 이런 금연 보조제를 사용하는 과정에서 이들을 상용하게 되어 시판되는 금연 보조담배의 장기적 사용시 인체의 안정성 여부에 대한 연구는 중요하리라 사료된다. 방 법 : 일반담배 및 금연 보조담배 3종의 담배연기추출물(cigarette smoke extract, CSE)을 기관지 상피세포에 24시간 노출 후 배양액에서 IL-6를 측정하였고 일반담배 및 허브담배, 쑥담배 노출 후 세포에서 IL-6 m RNA를 측정하여 비교하였다. 항산화 효과를 가진 N-acetyl-L-cysteine(NAC)를 일반 담배 및 금연보조담배 추출물에 함께 투여해 IL-6의 증가 억제여부를 보았다. 결 과 : 대조군에 비해 일반담배 및 금연보조담배3종에서 기관지 상피세포에 노출 시에 모두 의미 있는 IL-6증가를 관찰할 수 있었고, IL-6 m RNA도 같은 경향으로 증가 하였다. NAC를 함께 투여 시 일반 담배 및 허브담배 금연초에서는 IL-6의 증가를 의미 있게 억제하였지만 쑥담배에서는 억제하지 못하였다. 결 론 : 현재 우리나라에서 시판되고 있는 금연 보조담배 3종(허브담배, 쑥담배, 금연초)은 일반담배처럼 기관지 상피세포에 염증을 유발할 수 있어 장기적 사용시 인체의 안정성 여부에 대한 연구는 중요하리라 사료된다.

• 대한기계학회논문집A
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• 제35권11호
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• pp.1483-1490
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• 2011

전동기 일체형 유압액추에이터(EHA)는 전기모터와 직결되어 구동되는 유압펌프를 이용하여 유압 피스톤의 변위나 속도를 제어할 수 있도록 모듈화된 유압기기로 효율이 높고 독립된 동력원을 갖는 장점으로 인하여 항공기의 전자구동시스템에 적용되어 왔다. 최근에는 다양한 형태의 유압시스템이 적용되고 있는 건설중장비 분야에서 엔진과 전기모터를 결합한 하이브리드 기술이 개발됨에 따라 EHA의 활용범위가 확대될 것으로 예상된다. 본 연구에서는 편로드 유압실린더를 갖는 EHA가 적용된 유압시스템을 대상으로 펌프작동에 따른 유압실린더의 기동 및 정지특성을 고찰하기 위하여 EHA 내부 유압회로의 기능을 파악하고 동특성 모델을 유도하였으며 파일럿작동 체크밸브의 크래킹압력을 분석하여 개방 및 폐쇄특성을 예측하였으며 시뮬레이션을 통하여 분석된 결과를 검증하였다.