• 한국항공우주학회지
• /
• 제41권8호
• /
• pp.649-656
• /
• 2013

고양력장치는 항공기의 이착륙 및 실속성능에 큰 영향을 미친다. 그러므로, 이 논문에서는 주어진 2차원 플랩 형상에 대하여 가장 최적화된 플랩 위치와 변위각을 얻는 슬롯티드 플랩 설계 최적화 프로세스을 제안하였다. 플랩 변위각 및 Gap, Overlap을 양력을 증가시키는 주요 변수로 생각하였고, 정확한 해석결과를 위해 공력해석 소프트웨어로 ANSYS Fluent 13.0.0$^{(R)}$을 사용하였다. 최적화된 형상은 SQP(Sequential Quadratic Programming) 알고리즘을 통해 도출됐으며, 최적화된 플랩과 함께 ADSP(Aircraft Design Synthesis Program) in-house 성능해석 코드를 사용하여 항공기의 성능을 시험하였고, 이착륙 거리, 실속속도 등의 성능변수들이 KAS-VLA 인증규정을 만족하는 결과를 얻었다.

• Journal of Astronomy and Space Sciences
• /
• 제25권4호
• /
• pp.395-404
• /
• 2008

태양활동프록시(proxies)와 지구연평균 기온아노말리 시계열을 이용하여 기후변화에서 태양활동신호를 찾아보았다. 이를 위해 Lomb & Scargle의 피어리드그램(Periodgram)을 이용하여 태양활동프록시와 기온아노말리 시계열을 주기분석하였다. 또한 EMD(Empirical Mode Decomposition)과 MODWR MRA(Maxial Overlap Discrete Wavelet Transform Multi Resolution Analysis)를 적용하여 두 시계열을 성분분해하고 이들 중 비슷한 주기의 특성을 보이는 성분을 비교하였다. 태양활동프록시는 짧의 주기의 파워가 긴 주기의 파워에 비해서 큰 반면 기온아노말리는 긴 주기에서 더 큰 파워를 보였다 EMD에 의한 성분분해 결과는 약40년보다 긴 주기성을 갖는 성분을 분해해 낼 수 없었지만 잔차 성분은 비교할 수 있었다. MRA에 의한 성분분해를 통해 지구연평균 기온아노말리 시계열에서 태양활동의 변화에 의한 신호를 찾아내었다. 1960년부터 2007년까지 기온상승에 대한 태양의 기여도는 39%로 계산되었다. 기후민감성은 출력신호의 진폭에만 관계하여 기후시스템이 간단한 2계미분방정식으로 근사될 수 있는 가능성에 대해 토의하였다.

• 한국의류학회지
• /
• 제40권1호
• /
• pp.171-187
• /
• 2016

The study performed a comparison analysis of market brand patterns for slim-fit dress shirts and analyzed the body surface development figure of men in their 40s using 3D body scan data and developed slim-fit dress shirt patterns suitable for middle-aged men. The sizes of slim-fit dress shirt patterns showed a slight difference depending on brand. The overlap map of slim-fit dress shirt patterns for brands demonstrates how difference of one-dimensional sizes reflect on two-dimensional patterns. This map provides useful information for pattern design and allows and easy recognition of pattern size differences. A try-on system evaluation through 3D-Simulation allows a grasp of the fitness of neckline and size tolerance of under the arms in front, the silhouette of side lines, and overall fitness in front that also allows analysis of the front/back balance of a shirt in side, the size tolerance proportion in front/back, and the fitness of the arm-hole line. Thus, we obtained try-on results that were equivalent to wearing actual clothing. According to the drafting size suggested in the developed final pattern, the total width was 'C/2+5.5cm', and the front was set at 1cm bigger in the size difference of the front and back. The width of the front neck and the back neck was set identically at 'C/12', while the width of the front neck was set to 'C/12+1.5cm'. For the armhole depth, we added 'C/4+2cm', and '0.5cm and 1.5cm' for the width of the front and back to anthropometry. The results of the try-on evaluation through 3D-Simulation indicated that the fitness of the final slim-fit dress shirt pattern was superior to available slim-fit dress shirt patterns on the market and evaluated as superior to the types for middle-aged men.

• 한국언론정보학보
• /
• 제66권
• /
• pp.159-183
• /
• 2014

본 연구는 게임 플랫폼이 다양해짐에 따라 이용자 만족의 차원에서 게임 플랫폼 간에 어떻게 경쟁하고 있는지 분석하기 위해 게임 미디어 이용 후 획득하는 이용자 만족도를 한정된 자원으로 하여 PC, 콘솔, 모바일 게임 플랫폼 간에 경쟁 정도를 적소이론을 활용하여 분석하였다. 이를 위해 우선적으로 게임이용만족 요인을 도출하였는데, 분석 결과 게임 이용 후 만족 요인으로 '휴대성과 접근성', '생동감과 다양성', '활용성과 경제성', '관계성', 4가지의 만족 요인이 공통으로 도출되었다. 4가지 만족 요인에 대해 모바일이 가장 큰 적소 폭을 보여 세 플랫폼 중 만족 요인의 충족 범위가 넓은 반면, 콘솔이 가장 적은 적소 폭을 보여 만족 요인의 충족범위가 좁았다. 특히 플랫폼 간 경쟁상황을 보여주는 적소 중복과 경쟁우월지수 분석결과 4가지 만족 요인 모두에서 경쟁우위를 보인 플랫폼은 없었으며, 만족요인별로 플랫폼 간 경쟁의 정도와 우위가 달랐다. 플랫폼 간 경쟁력을 평가하기 위해 적소 중복과 경쟁우위 지수를 분석한 결과 만족 요인별로 차이가 있으나 전체적으로 PC와 모바일 간 중복 지수가 가장 높게 나타나 치열하게 경쟁하고 있는 상태임을 알 수 있었다. 콘솔의 경우 적소 폭이 적고 다른 플랫폼들의 적소 중복 지수도 낮기 때문에 다른 플랫폼과의 경쟁을 피하고 독립적으로 생존하고 있으나 특화된 만족을 제공하기 때문에 그만큼 시장 점유율이 줄어들 수밖에 없을 것으로 예측된다.

• 음성과학
• /
• 제1권
• /
• pp.153-200
• /
• 1997

In languages such as Japanese, it is very common to observe that short peripheral vowel are completely voiceless when surrounded by voiceless consonants. This phenomenon has been known as Montreal French, Shanghai Chinese, Greek, and Korean. Traditionally this phenomenon has been described as a phonological rule that either categorically deletes the vowel or changes the [+voice] feature of the vowel to [-voice]. This analysis was supported by Sawashima (1971) and Hirose (1971)'s observation that there are two distinct EMG patterns for voiced and devoiced vowel in Japanese. Close examination of the phonetic evidence based on acoustic data, however, shows that these phonological characterizations are not tenable (Jun & Beckman 1993, 1994). In this paper, we examined the vowel devoicing phenomenon in Korean using data from ENG fiberscopic and acoustic recorders of 100 sentences produced by one Korean speaker. The results show that there is variability in the 'degree of devoicing' in both acoustic and EMG signals, and in the patterns of glottal closing and opening across different devoiced tokens. There seems to be no categorical difference between devoiced and voiced tokens, for either EMG activity events or glottal patterns. All of these observations support the notion that vowel devoicing in Korean can not be described as the result of the application of a phonological rule. Rather, devoicing seems to be a highly variable 'phonetic' process, a more or less subtle variation in the specification of such phonetic metrics as degree and timing of glottal opening, or of associated subglottal pressure or intra-oral airflow associated with concurrent tone and stricture specifications. Some of token-pair comparisons are amenable to an explanation in terms of gestural overlap and undershoot. However, the effect of gestural timing on vocal fold state seems to be a highly nonlinear function of the interaction among specifications for the relative timing of glottal adduction and abduction gestures, of the amplitudes of the overlapped gestures, of aerodynamic conditions created by concurrent oral tonal gestures, and so on. In summary, to understand devoicing, it will be necessary to examine its effect on phonetic representation of events in many parts of the vocal tracts, and at many stages of the speech chain between the motor intent and the acoustic signal that reaches the hearer's ear.

• 터널과지하공간
• /
• 제9권1호
• /
• pp.36-47
• /
• 1999

세심한 제어발파를 위해서는 발파진동의 특성을 이해하는 것은 필수적이다. 본 연구에서는 진동이력분석을 응용하여 진동파의 특성을 조사하기 위해 몇가지 실험이이루어졌다. 충격진동과 자유진동의 구분, 지속시간, 진동의 크기에 대한 자유진동의 중첩효과, 지발당량의 증가에 따른 진동파의변화 등이 파형분석과 함께 연구되었다.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
• /
• pp.362-366
• /
• 2010

본 연구에서는 2단형 초음속 터빈의 유동에 대한 전산해석을 수행하고 그 결과를 비교 분석하였다. 2단 전체에 대한 계산을 상용 유동해석 프로그램인 $FLUENT^{TM}$사용하였다. 2단 동익에 대한 계산을 통하여 2단 동익의 중첩높이의 변화에 따른 터빈의 성능변화를 고찰하였다. 또한 2단 동익에서 슈라우드의 유 무에 따른 터빈의 성능변화를 고찰하였다.

• Bulletin of the Korean Chemical Society
• /
• 제15권1호
• /
• pp.74-77
• /
• 1994

Rare earth elements (REE) were individual separated by applying the gradient elution via HPLC using ${\alpha}-hydroxyisobutyric$ acid (HIBA) as an eluent. However, the overlap of Y and Dy peaks was too severe to obtain the resolution of these two peaks. The target transformation factor analysis (TTFA) was applied to resolve the elution peaks of Y and Dy. [A]$_{raw}$ formed from the absorbances of mixed solution was factor analyzed. The abstract factor analysis(AFA) was used to determine the number of components that contributed to the poorly resolved peaks. The error theory in the AFA showed that the number of components was 2. The test vectors which correspond to pure component were selected from the standard solutions of Y and Dy. TTFA was accomplished by target testing. The results showed that the resolution of two peaks as well as the determination of Y and Dy were possible by the factor analysis.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2006년도 추계학술대회논문집
• /
• pp.771-775
• /
• 2006

There has been much effort to find suitable methods for structural analysis in the mid-frequency region where traditional low frequency methods have increasing uncertainties whilst statistical energy analysis is not strictly applicable. Systems consisting of relatively stiff beams coupled to flexible plates have a particularly broad mid-frequency region where the beams support only a few modes whilst the plate has a high modal density and modal overlap. A system of two parallel beams coupled to a plate is investigated based on the wave method, which is an approximate method. The wave model is extended from a single-beam-plate system, to a plate with two identical beams which is modelled using a symmetric-anti symmetric technique. Experimental results such as powers and energy ratios show the validity of the analytical wave models.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2001년도 춘계학술대회 논문집
• /
• pp.848-853
• /
• 2001

Electrostatic actuation was adopted for ease of fabrication. We proposed a new driving scheme that uses the vector sum of force generated by comb-finger and by parallel plate. The moving and fixed electrodes are arranged to maximize the driving force. In this paper, an electrostatic field analysis is performed by Maxwell analysis tool for micro actuators. From the analysis, a comb-parallel type micro-actuator with 4${\mu}{\textrm}{m}$ width, 6${\mu}{\textrm}{m}$ overlap and 45${\mu}{\textrm}{m}$ height could be designed. In order to compare the new type of actuator with the conventional comb type of actuator, we arranged that both types have the same area and the same number of actuators. To make a high aspect ratio structure, we are developing fabrication process using SU-8 and electro-plating.