• 전자공학회논문지CI
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• 제41권6호
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• pp.91-99
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• 2004

본 논문은 H.264와 MPEG-4 간의 원활한 통신을 하기위한 두 가지 트랜스코딩 방법을 제안한다. 같은 공간적 시간적 해상도(spatio-temporal resolution)를 유지하는 트랜스코팅 방법과 공간적 해상도(temporal resolution)를 줄이는 트랜스코팅 방법을 제안한다. H.264 비트스트림(bitstream)이 MPEG-4 비트스트림으로 변환 시 H.264 블록형태를 MPEG-4에서 사용 할 수 있는 블록형태로 변환 시켜야 하며, 4×4 블록단위의 움직임 벡터도 8×8 블록단위의 움직임 벡터로 조정하여야 한다. 두 가지 제안된 트랜스코딩 방법은 직렬 화소영역 트랜스코팅 방법(cascade pixel-domain transcoding) 보다 MPEG-4 부호화기 측에서 4.1~5.1배 부호화 속도가 빠를 뿐만 아니라 영상의 화질 저하는 최고 0.3dB정도 밖에 떨어 지지 않는다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.231-233
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• 2003

Agricultural land use generally shows specific temporal characteristics of NDVI obtained from satellite data. In terms of winter wheat, a higher value compared with other land use types in May and a considerably low value in June could be discriminative features of temporal change of NDVI. In this study, the author examined methods for estimating winter wheat sown area in sub-pixel level of coarse resolution satellite data using temporal characteristics of NDVI. Application of the methods to the major grain production area in China exhibited properly a spatial distribution pattern of winter wheat sown area.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2007년도 한국음성과학회 공동학술대회 발표논문집
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• pp.59-63
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• 2007

Neuromagnetic fields were recorded from normal 10 subjects to investigate the time course of cerebral neural activation during the resolution of lexical ambiguity. All recordings were made using a whole-head 306-channel MEG (Elekta Neuromag TM Inc., $Vectorview^{TM}$). The observed activity was described by sLORETA (standardized low resolution brain electromagnetic tomography) techniques implemented in CURRY software (Neuroscan). In the results, bilaterally occipito-temporal lobe was activated at 170ms. At 250ms was associated with bilateral temporal lobe during ambiguous condition, whereas in left parietal, temporal lobe on unambiguous condition. The left frontal lobe, temporal lobe were activated at 350ms for all condition. At approximately 430ms, was activated in right frontal, temporal lobe on the resolving ambiguous condition, in left parietal lobe, right temporal lobe on the preserving ambiguous condition. In conclusion, the cerebral activations related to the resolving lexical ambiguity were right frontal lobe and the areas of mountainous ambiguity were left parietal lobe.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.860-863
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• 1997

FCM(Fuzzy Cognitive Map) is a fuzzy signed directed graph for representing causal reasoning which has fuzziness between causal concepts. Authors have already proposed FCM-based fault diagnostic scheme. However, the previously proposed scheme has the problem of lower diagnostic resolution. In order to improve the diagnostic resolution, a new diagnostic scheme based on extended FCM which incorporates the concept of fuzzy number into FCM is developed in this paper. Furthermore, an enhanced TAM(Temporal Associative Memory) recall procedure and pattern matching scheme are also proposed.

• 전자통신동향분석
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• 제8권2호
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• pp.69-91
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• 1993

In the conventional speech processing, the technique of FFT(Fast Fourier Transform) is usually applied to the finite number of samples within the window of specified length using the fixed sampling rate. In this case, the temporal resolution is dependent upon the length of window while the spectral resolution is dependent upon the number of samples within the window. Thus, once the temporal resolution is determined the spectral resolution is also determined or vice versa. To resolve this type of dilemma, a new type of bank-filter similar to the characteristics of cochlear model needs to be considered. Furthermore, wide dynamic range of cochlea certainly helps the stable extraction of speech features. In the paper, the human auditory system will be briefly introduced and previous works on auditory preprocessors based on cochlear model will be reviewed. As a conclusion, the design considerations of auditory preprocessors based on cochlear model will be addressed.

• Journal of Audiology & Otology
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• 제24권3호
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• pp.133-139
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• 2020

Background and Objectives: The Gaps-In-Noise (GIN) test is a clinically effective measure of the integrity of the central auditory nervous system. The GIN procedure can be applied to a pediatric population above 7 years of age. The present study conducted the GIN test to compare the abilities of auditory temporal resolution among typically developing children, children with speech sound disorder (SSD), and children with cognitive difficulty (CD). Subjects and Methods: Children aged 8 to 11 years-(total n=30) participated in this study. There were 10 children in each of the following three groups: typically developing children, children with SSD, and children with CD. The Urimal Test of Articulation and Phonology was conducted as a clinical assessment of the children's articulation and phonology. The Korean version of the Wechsler Intelligence Scale for Children-III (K-WISC-III) was administered as a screening test for general cognitive function. According to the procedure of Musiek, the pre-recorded stimuli of the GIN test were presented at 50 dB SL. The results were scored by the approximated threshold and the overall percent correct score (%). Results: All the typically developing children had normal auditory temporal resolution based on the clinical cutoff criteria of the GIN test. The children with SSD or CD had significantly reduced gap detection performance compared to age-matched typically developing children. The children's intelligence score measured by the K-WISC-III test explained 37% of the variance in the percent-correct score. Conclusions: Children with SSD or CD exhibited poorer ability to resolve rapid temporal acoustic cues over time compared to the age-matched typically developing children. The ability to detect a brief temporal gap embedded in a stimulus may be related to the general cognitive ability or phonological processing.

• 대한청각학회지
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• 제24권3호
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• pp.133-139
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• 2020

Background and Objectives: The Gaps-In-Noise (GIN) test is a clinically effective measure of the integrity of the central auditory nervous system. The GIN procedure can be applied to a pediatric population above 7 years of age. The present study conducted the GIN test to compare the abilities of auditory temporal resolution among typically developing children, children with speech sound disorder (SSD), and children with cognitive difficulty (CD). Subjects and Methods: Children aged 8 to 11 years-(total n=30) participated in this study. There were 10 children in each of the following three groups: typically developing children, children with SSD, and children with CD. The Urimal Test of Articulation and Phonology was conducted as a clinical assessment of the children's articulation and phonology. The Korean version of the Wechsler Intelligence Scale for Children-III (K-WISC-III) was administered as a screening test for general cognitive function. According to the procedure of Musiek, the pre-recorded stimuli of the GIN test were presented at 50 dB SL. The results were scored by the approximated threshold and the overall percent correct score (%). Results: All the typically developing children had normal auditory temporal resolution based on the clinical cutoff criteria of the GIN test. The children with SSD or CD had significantly reduced gap detection performance compared to age-matched typically developing children. The children's intelligence score measured by the K-WISC-III test explained 37% of the variance in the percent-correct score. Conclusions: Children with SSD or CD exhibited poorer ability to resolve rapid temporal acoustic cues over time compared to the age-matched typically developing children. The ability to detect a brief temporal gap embedded in a stimulus may be related to the general cognitive ability or phonological processing.

• 한국정밀공학회지
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• 제15권6호
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• pp.116-123
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• 1998

An interferometric microscope with an improved lateral resolution is presented. The nanometer resolution XY stage is integrated into standard temporal phase shifting interferometer. The nanometer resolution XY stage is used to position specimen in subpixel of CCD detector, therefore CCD detector's sampling is improved. Two scanning algorithms and those simulation results are also presented. The simulation results show that scanning algorithms improve CCD detector's sampling significantly, and interferometeric microscope's lateral resolution is improved also.

• 한국콘텐츠학회논문지
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• 제10권3호
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• pp.215-221
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• 2010

Time Resolved Imaging of Contrast Kinetics 기법을 이용한 4차원 자기공명혈관조영술 (TRICKS-MRA)영상과 기존 TOF-MRA영상을 비교하여 임상적 유용성에 대해 알아보고자 하였다. 총17명 중 뇌혈관 질환이 의심되는 11명과 뇌종양을 의심하는 6명을 대상으로 TOF-MRA와 TRICKS-MRA을 시행한 후 17 대상자 중 11명에서 DSA를 추가적으로 시행하였다. TOF-MRA는 공간해상력보다 시간해상력이 부족하였고, TRICKS-MRA에서는 TOF-MRA보다 공간분해능은 부족한 점이 많지만 영상판독에 큰 영향은 없었고 모든 대상자에서 동맥과 정맥의 구별이 가능하여 시간분해능이 우수한 것을 나타났다. 또한 종양과 혈관과의 관계성 평가에서 TOF-MRA보다 좋은 것으로 나타났다. TRICKS-MRA방법은 시간대별로 동맥, 모세혈관, 정맥기를 신속하면서 쉽게 4차원적으로 영상화가 가능하여 앞으로 임상에서 이용도가 더욱 증가 할 것으로 사료된다.

• 한국지리정보학회지
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• 제20권4호
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• pp.102-114
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• 2017

본 연구는 위성으로부터 유도된 강우자료 중 GPM IMERG의 정확도를 평가함으로써 미계측 혹은 비접근 지역에 대한 적용성을 판단하는 것을 목적으로 하였다. 연구대상 유역은 한반도 전역에 대하여 6개 권역으로 구분하여 분석을 수행하였다. 연구 유역에 대한 강우자료는 기상청에서 생산하고 있는 ASOS의 강우량 자료와 IMERG 위성강우자료를 이용하였다. 1시간의 시간해상도에서 평균 0.46의 상관계수를 가지며 24시간 해상도의 상관분석에서는 0.69로 높은 상관관계를 보이는 것으로 분석되었다. IMERG 강우량은 지상계측 강우량 보다 과소추정되는 것으로 분석되었으나, 시간 해상도가 낮아질수록 편이가 감소하는 것으로 분석되었다. 한편, 강우가 큰 기간의 사상 2개를 선정하여 분석한 결과 1시간 해상도의 상관계수는 0.68 및 0.69 값을 나타내었다. 또한 강우의 공간분포도 ASOS 및 IMERG 모두 유사한 분포를 보이는 것으로 분석되었다. 그러므로 IMERG 자료는 계측자료가 부족하거나 접근이 어려운 지역에서의 수문 기상 특성을 파악하는데 매우 유용할 것으로 판단된다. 향후 연구에서는 분석기간의 확장과 다양한 통계 분석 방법을 적용하여 위성강우의 정확도를 검증하는 연구를 수행할 계획이다.