• 수면정신생리
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• 제6권2호
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• pp.143-148
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• 1999

목 적: 지각 장애가 어떤 뇌의 부위와 기능에 장애가 있을 때 발생되는지를 알아보기 위해 정신과와 뇌손상 환자에서 신경심리 검사와 지각 장애와 관계성을 조사하였다. 방 법: 정신과 환자 69명, 뇌손상 환자 50명, 총 119명에서 Halstead Reitan 신경 심리 검사와 K-WAIS, MMPI를 시행하였다. MMPI 항목 중 지각 장애와 관계되는 9개 항목에서 산출된 점수와 신경심리 검사의 결과와의 상관 관계를 조사하였다. 또 정신과 환자에서 지각 장애 점수가 높은 지각 장애군 21명과 지각 장애가 없는 지각 장애 17명을 t-test로 비교하였다. 결 과: 뇌손상 환자군에서 지각 장애가 전두엽 기능을 보는 범주화 검사, 선로 잇기 검사, 촉각 수행 검사, 손끝 숫자 쓰기 검사와 우측 반구 기능을 보는 촉각 수행 검사의 위치, 동작성 점수, 빠진곳 찾기, 차례 맞추기, 토막 짜기 등과 유의한 상관 관계를 보였다. 또 피질하 기능을 보는 숫자 상징, 산수, 숫자 외우기와 유의한 상관 관계를 보였다. 정신과 환자의 높은 지각 장애군은 우측 반구 편측화 지수와 빠진 곳 찾기, 토막 짜기와 같은 우측 반구 기능에서 유의한 차이가 있었고, 또 이해, 어휘, 공통성과 같은 좌측 반구 기능에서도 유의한 차이가 있었다. 결 론: 지각 장애는 전두엽, 우측 반구, 피질하 구조의 기능과 깊은 연관성을 가지고 발생이 되며, 정신과 환자군에서는 좌측 반구의 기능도 영향을 주는 것으로 생각된다.

• The Journal of Korean Physical Therapy
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• 제20권3호
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• pp.1-7
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• 2008

Purpose: Implicit motor learning is the capacity to acquire skill through physical practice without conscious awareness of what elements of performance improved. This study investigated whether subacute stroke patients can implicitly learn a perceptual-motor task. Methods: We recruited 12 patients with subacute stroke and 12 age-matched controls. All participants performed a perceptual-motor task that involved pressing a button corresponding with colored circles (blue, green, yellow, red) on a computer screen. The task consists of 7 blocks composed of 10 repetitions for a repeating 12-element sequence (total 120 responses). Results: Both groups demonstrated significant improvement in acquisition performance. Reaction times deceased in both groups at similar rate within the sequential block trials (2-5 blocks), and reaction times increased at a similar rate when the task paradigm was transferred from the sequential block trial to the random block trial (5-6-7 blocks). Conclusion: The results of this study suggest that patients with sub-actue stroke can implicitly learn a perceptual motor skill. Although explicit instructions should be used to focus the learner's attention rather than provide information about the task, the application of implicit motor learning strategies in the rehabilitation setting may be beneficial.

• 말소리와 음성과학
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• 제10권1호
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• pp.65-74
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• 2018

The purpose of this study is to investigate age-specific features of 2;1- to 4;1-year -olds' production of monophthongs and diphthongs through both auditory perceptual analysis and acoustic analysis. Test material included {vowel+'da'} consisting of 7 monophthongs and 10 diphthongs and meaningful words beginning with vowels. The percentage of correct vowels was used for perceptual analysis and Praat(5.2.12) was used for acoustic analysis, analyzing variables related to monophthongs and diphthongs. The results of this study are as follows: First, perceptual analysis showed that children from an age group of 2;1 to 2;8 years showed significant difference in the accuracy level of both monophthongs and diphthongs as compared to those aged 2;9 to 3;4 years and those aged 3;5 to 4;1 years. Second, the results of acoustic analysis provided that formant (F1 and F2) of monophthong, in general, tended to decrease as age increased. In terms of F2 differentiation slope and regression slope, which were diphthong-related variables, the age group of 3;5 to 4;1 years showed a large general slope change.

• ETRI Journal
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• 제36권3호
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• pp.479-489
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• 2014

This paper presents a model-based image steganography method based on Watson's visual model. Model-based steganography assumes a model for cover image statistics. This approach, however, has some weaknesses, including perceptual detectability. We propose to use Watson's visual model to improve perceptual undetectability of model-based steganography. The proposed method prevents visually perceptible changes during embedding. First, the maximum acceptable change in each discrete cosine transform coefficient is extracted based on Watson's visual model. Then, a model is fitted to a low-precision histogram of such coefficients and the message bits are encoded to this model. Finally, the encoded message bits are embedded in those coefficients whose maximum possible changes are visually imperceptible. Experimental results show that changes resulting from the proposed method are perceptually undetectable, whereas model-based steganography retains perceptually detectable changes. This perceptual undetectability is achieved while the perceptual quality - based on the structural similarity measure - and the security - based on two steganalysis methods - do not show any significant changes.

• 한국의상디자인학회지
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• 제18권3호
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• pp.37-56
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• 2016

Gestalt psychology is a theory of psychology to organize separate stimuli perceived by people's vision to incorporate them into significant types, and this also is applied in terms of the brand awareness of consumers. This study considered which influence the Gestalt psychology theories have upon the fashion consumers' information processing in fashion advertisement. The results are as follows. The principles of the totality and the perceptual organization in the Gestalt psychology are allowing fashion consumers to perceive information through advertisement and to be capable of understanding it a little more easily and clearly in the process. As for the principle of totality, an integrated Gestalt was formed by combining the stimulant elements of fashion ads and the brand schema of consumers. The principles of figure and background that were part of the perceptual organization theory enabled the consumers to pay attention to, choose and focus on some of the objects of perception in an easier and faster way. The principle of perceptual grouping was used to draw attention from the consumers by simplifying the objects of perception and then by combining them or making them look complete. Therefore the more advanced application of the principles and laws of Gestalt psychology is expected to make fashion consumers' way of looking at ads more well balanced and positive in a more efficient and convincing manner.

• 방송공학회논문지
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• 제14권2호
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• pp.210-218
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• 2009

자연 3D 환경에서와 달리 3D 디스플레이를 통해 제시되는 대상의 깊이와 모양은 관찰거리에 따라서 체계적으로 왜곡되어 지각된다. 동일한 3D 디스플레이를 시청하는 다수의 시청자가 상이한 3D 깊이감과 모양감을 지각하는 것은 바람직하지 않은데, 이와 같은 3D 깊이감/모양감 왜곡 문제를 해결하기 위해서는 3D 깊이감과 모양감의 왜곡정도를 측정하는 정교한 도구가 필요하다. 본 연구는 3D 깊이감과 모양감 왜곡의 문제를 해결하기 위한 기반연구로서 3D 깊이감과 모양감 왜곡정도를 측정할 수 있는 깊이감/모양감 왜곡 측정도구를 제안한다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1661-1663
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• 2007

The contrast of display is one of the important specifications. Even if the contrast indicates luminance range which is a capability of the display and is greater in lower luminance or higher luminance, we consider that the greater contrast gets not the better performance. It is not the same value in human visual system. In practice, it is difficult to achieve the full dynamic range seen by human beings using electronic equipment. Therefore, we consider ambient condition and human perception to calculate perceptual contrast using the CIECAM02. In this paper, we propose perceptual contrast that is calculated using the brightness of CIECAM02.

• 음성과학
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• 제6권
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• pp.163-179
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• 1999

For the set up, management and repair of a mobile communication system, continuous estimation of speech quality is required. Speech quality measurement can be conducted by listener's judgement in a subjective test such as MOS (Mean Opinion Score) test. However, this method is laborious, expensive and time-consuming, it is advisable to predict subjective speech quality via objective measures. This paper presents a robust objective speech quality measure, PLP-CMS (Perceptual Linear Predictive-Cepstral Mean Subtraction), which can predict subjective speech quality in mobile communication systems. PLP-CMS has a high correlation with subjective quality owing to PLP (Perceptual Linear Predictive) analysis and shows a robust performance not being influenced by PSTN (Public Switched Telephone Network) channel effects due to CMS (Cepstral Mean Subtraction). To prove the performance of our proposed algorithm, we carried out subjective and objective quality estimation on speech samples which are variously distorted in a real mobile communication system. As a result, we demonstrated that PLP-CMS has a higher correlation with subjective quality than PSQM (Perceptual Speech Quality Measure) and PLP-CD (Perceptual Linear Predictive-Cepstral Distance).

• 음성과학
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• 제6권
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• pp.197-217
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• 1999

In a noisy class, the acoustic-phonetic features of the teacher and the perceptual features of learners are changed comparison with a quiet environment. Acoustical analyses were carried out on a set of French monosyllables consisting of 17 consonants and three vowel /a, e, i/, produced by 1 male speaker talking in quiet and in 50, 60 and 70 dB SPL of masking noise on headphone. The results of the acoustic analyses showed consistent differences in energy and formant center frequency amplitude of consonants and vowels, $F_1$ frequency of vowel and duration of voiceless stops suggesting the increase of vocal effort. The perceptual experiments in which 18 undergraduate female students learning French served as the subjects, were conducted in quiet and in 50, 60 dB of masking noise. The identification scores on consonants were higher in Lombard speech than in normal speech, suggesting that the speaker's vocal effort is useful to overcome the masking effect of noise. And, with increased noise level, the perceptual response to the French consonants given had a tendency to be complex and the subjective reaction score on the noise using the vocabulary representative of 'unpleasant' sensation to be higher. And, in the point of view on the L2(second language) acquisition, the influence of L1 (first language) on L2 examined in the perceptual result supports the interference theory.

• 한국음향학회지
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• 제15권5호
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• pp.61-64
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• 1996

본 논문에서는 귀의 주요한 특징인 주파수가중특성과 Bark-scale이라는 비선형주파수특성을 선형주파수축상에서 고려한 거리함수를 정의하고, 이 거리함수로부터 새로운 LPC cepstrum 계수를 제안한다. 귀의 특성은 선형주파수축에서 로그 스펙트럼에 대한 가증함수로서 표현되며, 이 가중함수는 cepstrum 영역에서 콘볼루션으로 표현되어 콘볼루션적으로 가중되는 LPC cepstrum을 정의하게 된다. 제안된 cepstrum 계수에서 정의된 가중함수는 A-weighting의 영향과 비선형주파수축의 영향을 하나의 가중함수로 통합하여 사용된 것이다. 제안된 파라미터의 성능을 음성인식 실험을 통하여 검증하였다.