• 한국통신학회논문지
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• 제22권11호
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• pp.2531-2542
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• 1997

This paper describes a method for region segmentation and string extractionin documents which are mixed with text, graphic and picture images by the use of the structural characteristic of connceted components. In segmentation of non-text regionas, with connection-characteristic functions which are made by structural characteristic of connected components, segmentation process is progressed. In the string extraction, first we organize basic-unit-region of which vertical and horizontal length are 1/4 of average length of connection components. Second, by merging the basic-unit-regions one other that have smaller values than a given connection intensity threshold. Third, by linking the word blocks with similar block anagles, initial strings are cresed. Finally the whold strings are generated by merging remaining word blocks whose angles are not decided, if their height and prosition are similar to the initial strings. This method can extract strings that are neither horizontal nor of various character sizes. Through computer exteriments with different style documents, we have shown that the feasibility of our method successes.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
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• pp.533-536
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• 1999

We consider digital implementation problems of continuous-time controllers. In general, digital controllers use fixed point representation of number and of finite word length(FWL). Under these conditions, this paper investigates the closed-loop stability caused by three design constraints; (i) finite precision representation of the controller parameters, (ii) realization forms such as direct form, cascade form, and parallel form, and (iii) sampling time. We calculate the coefficient stability margins of both predesigned controllers and controller to be implemented. This method can be applied to determine the word length, realization structure, and sampling time so that remains the stability.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2192-2195
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• 2003

This parer proposes a power-line phase measurement algorithm which is based on the recursive implementation of sliding-DFT. Usage of the single DFT coefficient in the conventional sliding-DFT based power-line phase measurement brings a significant error propagation when implemented in hardware with finite word-length arithmetic operations. The proposed algorithm utilizes all the N-point DFT coefficients in the recursion. Performance degradation caused by the finite word- length implementation of the algorithm is analyzed and verified with computer simulations. The robustness of the proposed phase measurement algorithm against the erroneous implementation is also confirmed by the performance analysis and simulation.

• 말소리와 음성과학
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• 제8권1호
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• pp.37-44
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• 2016

The goal of the current study is to investigate how the sound change is reflected in production or in perception, and what the effect of lexical frequency is on the loss of sound contrasts. Specifically, the current study examined whether the vowel length contrasts are retained in Korean speakers' productions, and whether Korean listeners can distinguish vowel length minimal pairs in their perception. Two production experiments and two perception experiments investigated this. For production tests, twelve Korean native speakers in their 20s and 40s completed a read-aloud task as well as a map-task. The results showed that, regardless of their age group, all Korean speakers produced vowel length contrasts with a small but significant differences in the read-aloud test. Interestingly, the difference between long and short vowels has disappeared in the map task, indicating that the speech mode affects producing vowel length contrasts. For perception tests, thirty-three Korean listeners completed a discrimination and a forced-choice identification test. The results showed that Korean listeners still have a perceptual sensitivity to distinguish lexical meaning of the vowel length minimal pair. We also found that the identification accuracy was affected by the word frequency, showing a higher identification accuracy in high- and mid- frequency words than low frequency words. Taken together, the current study demonstrated that the speech mode (read-aloud vs. spontaneous) affects the production of the sound undergoing a language change; and word frequency affects the sound change in speech perception.

• 말소리와 음성과학
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• 제2권3호
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• pp.81-89
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• 2010

Korean and three other languages (English, Arabic, and Japanese) were compared with regard to the compensatory movements in a VC (Vowel and Consonant) sequence and word. For this, Korean data were collected from an experiment and the other languages' data from literature. All the test words of the languages had the same syllabic contexture, i.e., /CVCV(r)/, where C was an oral stop and intervocalic consonants were either bilabial or alveolar stops. The present study found that (1) Korean is most striking in the durational variations of segments (vowel and the following hetero-syllabic consonant); (2) unlike the three languages that show a constant sum of VC, Korean yields a three-way distinction in the length of VC according the type (lax unaspirated vs. tense unaspirated vs. tense aspirated) of the following stop consonant; (3) a durational constancy is maintained up to the word level in the three languages, but Korean word duration varies as a function of the feature tenseness of the intervocalic consonants; (4) consonant duration is proven to differentiate Korean the most from the other languages. It is suggested that the durational difference between a lax consonant and its tense cognate(s) and the degree of compensation between V and C are determined by the phonology in each language.

• 음성과학
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• 제7권2호
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• pp.37-50
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• 2000

This paper describes a test of everyday speech understanding ability, in which a listener's utilization of the context-situational information of speech is assessed, and is compared with the utilization of acoustic-phonetic information. The test items are sentences which are presented in a babble type of noise, and the listener response is the key word in the sentence. The key words are always two-syllabic nouns and the questioning sentences are added to obtain the responding key words. Two types of sentences are used. One is the high-predictable sentences for which the key word is somewhat predictable from the context. The other is the low-predictable sentences for which the key-word cannot be predicted from the context. Both types are included in six 40-item forms of the test, which are balanced for intelligibility, key-word familiarity and predictability, phonetic content, and length. Performance of normally hearing listeners shows significantly different functions for various signal-to-noise ratios. The potential applications of this test, particularly in the assessment of speech understanding ability in the hearing impaired, are discussed.

• 건축역사연구
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• 제25권5호
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• pp.41-50
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• 2016

This thesis mainly deals with how 'count of Ryang' was used in the Daehan Empire. Count of Ryang means how many purlins were used in the building with longitudinal section. As a result, the notion of Ryang in the Daehan Empire does not differ from now one. But the usages of that are different from the Joseon Dynasty, and from the present. In the Daehan Empire, count of Ryang mainly was appeared with another word, count of Kan. In the Joseon Dynasty, they used the count of Ryang combined with Kan. Count of Kan had the meaning of purlin-directional length. By doing that, count of Ryang indicates the size of flank, count of Kan indicates the length of front. But in the Daehan Empire, count of Kan, especially the beam-directional length was considered at first, and then count of Ryang. Separately they used another count of Kan meaning the area of building. By using the combined words, count of Kan and Ryang in the beam direction, they got focused on the frame of wooden structure than before.

• 인지과학
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• 제20권3호
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• pp.291-307
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• 2009

본 연구에서는 대학생들이 어려운 글과 쉬운 글을 읽는 동안에 안구운동을 측정하였다. 비교 분석은 전반적인 수준과 어절 수준에서 이루어졌다. 전반적인 수준을 보면, 평균 고정시간은 어려운 글을 읽을 때가 217ms로 쉬운 글을 읽을 때의 190ms에 비해 길었고, 도약거리는 어려운 글을 읽을 때가 3.7자로 쉬운 글을 읽을 때의 4.8자에 비해 짧았다. 어절 수준에서는 어려운 글의 단일 고정시간(single fixation time: 227ms)과주시시간(gaze duration: 266ms)이쉬운글(각각195ms와 210ms)에서보다 더 길었다. 어려운 글과 쉬운 글 모두에서 단어 빈도 효과와 어절 길이 효과가 있었으며 빈도에 따른 고정시간의 차이와 길이에 따른 고정시간의 차이는 모두 어려운 글에서 더 크게 나타났다.

• 한국통신학회논문지
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• 제31권5A호
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• pp.493-500
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• 2006

논문은 OFDMA/TDD 시스템에서 하향링크 빔 형성 송신기의 효율적인 구조와 설계 변수의 최적화에 대하여 고찰하였다. 다수의 송신 안테나를 사용하는 하향링크 빔 형성 송신기 설계에 있어 다수의 사용자에 대한 효율적인 빔 형성 구조 설계와 송신기 블록의 word-length 는 송신기의 성능과 하드웨어 복잡도 측면에서 중요한 설계 변수가 된다. 본 논문에서는 기지국 수신에서 사용자 구분 없이 부반송파별 가중치만 메모리에 저장하고, IFFT 입력의 부반송파 단위에서 사용자에 따라 할당된 부반송파의 가중치를 고속으로 계산하여 적용하는 효율적인 빔형성기 구조를 제시하였다. 또한, 고정 소수점 시뮬레이션을 통하여 최적의 설계 변수를 분석하였다. 제시한 구조는 프레임 당 최대 사용자 수에 비례하게 메모리를 줄일 수 있으며, 또한 기지국 수신에서 사용자 제어 없이 FFT 출력을 바로 송신에 적용하여 OFDM 한 심볼의 처리 시간을 줄일 수 있고 송신기에서 빔 형성 계산은 별도의 처리 시간을 요구하지 않는 장점이 있다.

• 한국통신학회논문지
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• 제29권11C호
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• pp.1491-1497
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• 2004

구현하기 위하여 고정 소수점 연산기에 적합하도록 최적화를 수행하였다. 최적화 과정은 크게 부호화기의 음질을 고려하여 프로세서의 데이터 워드 길이를 결정하는 과정과 자주 사용되는 초월 함수를 고정 소수점 연산을 통해 구현하는 것으로 구성된다. 데이터 워드 길이를 결정하기 위하여 심리음향 모델 과정의 고정 소수점 연산 오차와 이 오차가 비트 할당 과정에 영향을 미칠 확률 사이의 관계를 통계적 모델로 정의하였다. 여기서 정의된 모델을 사용하여 고정 소수점 연산 오차에 의한 영향이 1% 이내가 되도록 24비트의 데이터 워드를 선택하였다. 최적화된 고정 소수점 심리음향 모델을 사용한 MP3 부호화기의 음질은 부동 소수점 부호화기에 비해 W-R의 음질평가 점수를 기준으로 평균 -0.2 이내의 구분하기 힘든 수준의 음질 저하를 보였다