• 제목/요약/키워드: length adaptation

검색결과 169건 처리시간 0.026초

잡음환경에서 구름 볼 베어링의 결함검출을 위한 ALE의 적용 (Application of ALE for detection of rolling ball bearing defects in noisy environment)

  • 김영태;최만용;김기복;박해원;박정학;김종억;류준
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 추계학술대회 논문집
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    • pp.86-91
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    • 2004
  • It is very important to detect the bearing defects in rotating machinery since the critical failure of bearing cause a machinery shutdown. However it is difficult to detect the vibration signal resulting from the initial defects of bearing because of the high level of broadband noise. A signal processing technique, called the adaptive line enhancer(ALE) as one of adaptive filter, is studied in this work. This technique is to eliminate broadband noise without a prior knowledge of the noise and signal characteristics. Also we propose the optimal methods for selecting the three main ALE parameters such as correlation length, filter order and adaptation constant used in the adaptative process. Vibration signals for three abnormal bearings, including inner and outer raceways and ball defects, were acquired from Anderon(angular derivative of radius on)meter. The experimental results showed that the proposed technique can reliably detect the bearing defective signals masked by broadband noise.

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상태레벨 공유를 이용한 MLLR 적응화의 회귀클래스 생성에 관한 연구 (A Study on Regression Class Generation of MLLR Adaptation Using State Level Sharing)

  • 오세진;성우창;김광동;노덕규;송민규;정현열
    • 한국음향학회지
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    • 제22권8호
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    • pp.727-739
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    • 2003
  • 본 논문에서는 HM-Net (Hidden Markov Network)을 다양한 태스크에의 적용과 화자의 특성을 효과적으로 나타내기 위해 HM-Net 음성인식 시스템에 MLLR (Maximum Likelihood Linear Regression) 적응방법을 도입하였으며, HM-Net 학습 알고리즘을 개량하여 회귀클래스 생성방법을 제안한다. 제안방법은 PDT-SSS (Phonetic Decision Tree-based Successive State Splitting)알고리즘의 문맥방향 상태분할에 의한 상태레벨 공유를 이용한 방법이다. 즉, 문맥방향의 각 상태에 적응화자 음성데이터에 포함된 문맥정보를 분할하여 적응화될 음소환경을 결정하는 것이다. 따라서 제안방법은 새로운 화자로부터 문맥정보와 적응화 데이터의 발성 양에 의존하여 결정된 많은 적응 파라미터들을 (평균, 분산) 자유롭게 제어할 수 있게 된다. 제안방법의 유효성을 확인하기 위해 국어공학센터 (KLE) 452 데이터와 항공편 예약관련 (YNU200) 연속음성을 대상으로 인식실험을 수행한 결과, 음소인식, 단어인식, 연속음성인식에 대해서, 평균 34∼37%, 평균 9%, 평균 20%의 성능 향상을 각각 보였다. 또한 적응화 데이터의 양에 따른 인식성능 비교에서 제안방법을 적용한 인식 시스템이 적응 데이터의 양이 적은 경우에도 향상된 인식률을 보여 MLLR 적응방법의 특성을 만족하였다. 따라서 MLLR 적응방법을 도입한 HM-Net 음성인식 시스템에 제안한 회귀클래스 생성방법이 유효함을 확인할 수 있었다.

대전지역 중국 및 일본 유학생의 국적 및 거주 기간에 따른 한식 적응도와 급식 만족도 (Adaptation for Korean Foods and Satisfaction for Foodservice by Different Residence Periods of Chinese and Japanese University Students in Daejeon)

  • 류시현;조윤혜;한이랑
    • 동아시아식생활학회지
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    • 제24권1호
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    • pp.143-155
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    • 2014
  • The purpose of this study was to analyze adaptation for Korean foods and satisfaction for university foodservice by nationality and residence period of Chinese and Japanese university students in Daejeon, Republic of Korea. Among 330 questionnaires distributed to Chinese and Japanese students, 294 complete questionnaires (89.1%) were analyzed. The questionnaire included two 5-point scales for measuring levels adaptation of for Korean food and satisfaction with university foodservice, respectively. Japanese students' level of adaptation for Korean food (3.16) was significantly higher than that of Chinese students (2.96). As the length of residence in Korea increased, the frequency of using university lunch service per week significantly decreased. The main factor when selecting a menu item was food taste (39.8%, 22.8%) in both Chinese and Japanese students, whereas the next main factor was preference (16.4%) in Chinese students and nutrition (18.7%) in Japanese students. The preferred cooking methods for meat were stir-frying (31.6%) and roasting (25.9%). For fish, Chinese students preferred braising (32.7%), whereas Japanese students preferred roasting (26.8%). Both Chinese and Japanese students preferred sukchae (45.6%, 43.1%) for vegetables. Factor analysis grouped 17 items measuring university foodservice into four factors, 'sanitation & employee service', 'physical environment', 'food' and 'customized menu & information' and the mean scores were 3.56, 3.30, 3.20 and 3.00, respectively. Chinese students were significantly more satisfied than Japanese students with the 'physical environment', 'sanitation & employee service' and 'customized menu & information'. These results suggest that efforts such as developing a greater variety of menu items with mild tastes and somewhat less flavor, applying preferred cooking methods, offering special menus for foreign students, providing nutrition information on menus, and offering a description of menu items in the foreign languages could improve Chinese and Japanese students' levels of satisfaction with university foodservice.

DASH 기반 멀티미디어 스트리밍 서비스에서 사용자 체감품질 향상을 위한 비트율 적응 기법 (A Video Bitrate Adaptation Algorithm for DASH-Based Multimedia Streaming Services to Enhance User QoE)

  • 서동은;장인선;백상헌
    • 한국통신학회논문지
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    • 제39B권6호
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    • pp.341-349
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    • 2014
  • Dynamic adaptive streaming over HTTP (DASH)는 최근 주목받고 있는 스트리밍 기술이다. DASH 클라이언트는 연속적으로 가용 네트워크 대역폭을 측정하고, 이를 기반으로 향후 다운받을 비디오 세그먼트의 비트율을 결정한다. 본 고에서는 최소 재생 버퍼 레벨을 보존하여 가변적인 네트워크 환경에서도 사용자 체감 품질 저하를 야기하는 재생 끊김 현상, 재생 중 비디오 품질의 급격한 변화 등을 효율적으로 방지하는 비트율 적응 알고리즘인 QoE-enhanced adaptation algorithm over DASH (QAAD)를 제안한다. 또한 DASH 테스트베드 상에 QAAD와 재생 버퍼를 고려한 기존의 알고리즘 (즉, QDASH[9])을 구현하여 실험적으로 성능을 비교 및 분석하였다. 네트워크 환경이 급변하는 환경에서 실험을 수행한 결과, QDASH는 재생 끊김 현상 및 비디오 화질의 잦은 변화가 발생하는 반면, QAAD는 재생 끊김 없이 안정적인 비디오 화질을 제공하는 것을 확인할 수 있었다.

부산광역시 외국인 유학생의 거주기간에 따른 한국 식생활 적응 및 교내급식 만족도 조사 (A Study on the Adaptation to Korean Food and Satisfaction with University Foodservice by Residence Period of International Students in Busan)

  • 홍경희;이현숙
    • 한국식생활문화학회지
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    • 제36권4호
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    • pp.349-361
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    • 2021
  • This study was conducted to investigate the dietary adaptation and use of the university foodservice (UF) in Korea according to the residence period of foreign students. The average length of residence in Korea of t he subjects was 8.2 months. The period of residence was divided into quartiles: 1-4 months in the first quartile (average 2.2 months), 5-7 months in the second quartile (average 6.3 months), 8 months in the third quartile, and 9-66 months in the fourth quartile (average 18.3 months). The regularity of meals tended to be the highest in the 1st quartile and lowest in the 2nd quartile and then increased in the 3rd and 4th quartiles. The frequency of consumption of delivery food and convenience store food was lowest in the first quartile and highest in the second quartile and then decreased with the period of residence. The frequency of night eating increased according to the period of residence after the second quartile. The degree of adaptation to Korean foods was highest in the first quartile. The use of the university cafeteria was significantly higher in the 1st and 4th quartiles than in the 2nd and 3rd quartiles (p<0.05, p<0.01, respectively). The satisfaction with the UF decreased as the residence period increased. Based on these results, since international students are very positive and try to adapt to the dietary life in Korea in their early years of studying in Korea, it would be desirable to intensively support them to adjust to their dietary life at this time. In addition, since it takes about 18 months or more to assimilate the Korean food culture and show positive changes, it is necessary to continuously operate the Korean food culture adaptation program for international students over this period.

탈북자 가족 구성원의 가족관계 인식에 관한 조사연구 : 탈북자 가구주 및 그 배우자의 인식을 중심으로 (Family Relationship among North Korean Migrant Families in Early Adaptation : An Empirical Study Centered on Family Members' Perception)

  • 이기영;성향숙
    • 한국사회복지학
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    • 제47권
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    • pp.243-271
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    • 2001
  • This study examines family relationship among North Korean migrant families in early adaptation (approximately, up to $5{\sim}6$ years after arrival in the South). Family cohesion, communication, power relationship, and conflicts and domestic violence among family members were examined by the perceptions of 67 male and female householders and their spouses. In the four areas of family relationship, the subjects have quite positive perceptions and shows no critically significant difference on the perceptions between before and after arrival. However, positive perception on family relationship gradually decreases as the length of time of in the South increases with linear or nonlinear patterns according to subcategories of family relationship. These findings suggest several social work practice implications in resettlement assistance for the North Korean migrant families.

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데이터 전송률의 적응성을 고려한 CDMA2000 1X EV-DO 시스템의 순방향 데이터 서비스 용량 분석 (Forward Link Data Service Capacity Considering Data Rate Adaptation in CDMA2000 1X-EVDO Systems)

  • 최우용;임동구
    • 대한산업공학회지
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    • 제37권3호
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    • pp.229-233
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    • 2011
  • The existing approaches for analyzing the data service capacity of CDMA2000 1X EV-DO (Evolution-Data Only) systems have focused on deriving the maximum number of active customers assuming that the data rates provided to the customers can be determined beforehand. However, we have seen that through real experiment, the data rates actually provided to the customers adaptively change according to the number of active customers. In this paper, we propose new capacity analysis model considering the data rate adaptation. Numerical examples are also presented to obtain the maximum input traffic rates for various values of the length of data burst and the required mean delay bound.

유아복 제품치수 인지도 및 맞음새 조사 (A Study on Fitness and Awareness of Sizing System of Infants′Wear)

  • 김지연;손희순
    • 복식문화연구
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    • 제8권2호
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    • pp.272-281
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    • 2000
  • The purpose of this study is to provide for the basic data useful to the effective production. For this purpose, 180 Korean mothers who bring up from newborns to four-year-old babies were sampled to survey the problems on size occurred by wearing and purchasing the Infants'Wear and positively identify the factors affecting the fitness. Data is processed by a computer(SAS) and analyzed by using frequency, perentage, mean, χ²-test, Duncan-test. The main results of this study are as follows ; 1. Consumers'awareness of sizing system of Infant's wear tent to present relatively high and tend to purchase their infants'wear larger than actual sizes or that consumers'preferences depend little on size adaptation. 2. As a result of analyzing the part not fit, neck circumference, waist circumference, total length, neck back-waist length is short, sleeve length, pants length, shoulder length is big. In all, it has been found through this study that fitness and awareness of sizing system of Infant's Wear in purchasing infants'wear was influenced by many external factors. Therefore, in order to maximize the size adaptability for infants, Infants'Wear must be present the reasonable sizes and specifications for infants'wear in consideration of domestic and foreign specifications and infants'health condition.

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AAL2 스위치 구현 방안 및 CDMA 환경에서의 성능 분석 (Design of AAL2 Switch and Performance Analysis)

  • 김만규;임세윤;이성창;김정식
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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    • pp.159-162
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    • 2001
  • AAL2 is an adaptation layer that is supposed to support delay-sensitive applications with low bit-rate, short, variable packet length in a bandwidth-efficient way. For the switching of AAL2 service channels, AAL2 network is needed, which consists of AAL2 switching nodes. In this paper, The architecture of the unit AAL2 switch is proposed and the performance is analyzed in the CDMA environment.

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New Image Mapping Algorithm for 3D Integral Imaging Display System used in Virtual Reality

  • Suk, Myung-Hoon;Min, Sung-Wook
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.41-45
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    • 2005
  • A new algorithm of the image mapping which is a technique of the elemental image generation is proposed. The proposed method is based on the characteristics of the lens array such as the number, the size and the focal length of the elemental lens. The 3D image generated by 3D graphic API such as OpenGL can be directly adopted without the complex adaptation. Since the image mapping using the proposed method can enhance the speed of the elemental image generation, the computer- generated integral imaging system can be applied to virtual reality system.

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