• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.1
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• pp.12-20
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• 2002

To control the noise of an enclosed sound field, we built a state space model using the acoustic modal parameter description. Using the state space model, we can investigate the controllability and observability, and find an appropriate position of control speaker and microphone to control sound field of the enclosed space. We implemented LQR(linear quadratic regulator) controller and reduced order observer to reduce the first acoustic mode. Experiments showed satisfactory results of 4∼10 dB reduction of magnitude of the first acoustic mode, and support the feasibility of the proposed scheme to lightly damped acoustic field.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.7
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• pp.1069-1076
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• 2012

We use largely two methods, how to control the noise of the KTX, they are the passive noise control method and the active noise control method. The passive noise control has been used in a variety of ways since the KTX opening day, but lately it has shown the technical limitations by being dropped sharply. So, it is getting important to conduct the research about ANC that is able to reduce the ambient noise when the environmental-factor changes and be installed easily. To reduce a three-dimensional closed-space sound field like a car of a high-speed rail is hard to do using single channel ANC control system. Therefore we have to model the paths of the noise exactly for reducing the noise. And the control speakers and the error mics should be designed for optimal position. In this paper, we designed the transfer functions for modeling the noise paths under the influence of the distance between control speakers & error mics and primary noise speaker in TEST-BED where there is modeled as actual interior of KTX. We have made the modeling and the simulations of interior environment of KTX car by using three frequency bands of 120Hz, 280Hz, 360Hz. After the modeling, we compared the performance of active noise control and also we analyzed what to affect with difference in distance. After comparing of the performance using Pure Tone 120Hz, 280Hz, 360Hz at each modeling and then we simulated ANC for KTX's interior noise which we measured really and analyzed.

• The Journal of the Acoustical Society of Korea
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• v.20 no.4E
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• pp.52-60
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• 2001

This paper describes real time implementation of subband sound localization system on a floating-point DSP TI TMS320C31. The system determines two dimensional location of an active speaker in a closed room environment with real noise presents. The system consists of an two microphone array connected to TI DSP hosted by PC. The implemented sound localization algorithm is Subband CPSP which is an improved version of traditional CPSP (Cross-Power Spectrum Phase) method. The algorithm first split the input speech signal into arbitrary number of subband using subband filter banks and calculate the CPSP in each subband. It then averages out the CPSP results on each subband and compute a source location estimate. The proposed algorithm has an advantage over CPSP such that it minimize the overall estimation error in source location by limiting the specific band dominant noise to that subband. As a result, it makes possible to set up a robust real time sound localization system. For real time simulation, the input speech is captured using two microphone and digitized by the DSP at sampling rate 8192 hz, 16 bit/sample. The source location is then estimated at once per second to satisfy real-time computational constraints. The performance of the proposed system is confirmed by several real time simulation of the speech at a distance of 1m, 2m, 3m with various speech source locations and it shows over 5% accuracy improvement for the source location estimation.

• Smart Media Journal
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• v.12 no.11
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• pp.77-85
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• 2023

After COVID-19, communication through online platforms has increased, leading to an accumulation of massive amounts of conversational text data. With the growing importance of summarizing this text data to extract meaningful information, there has been active research on deep learning-based abstractive summarization. However, conversational data, compared to structured texts like news articles, often contains missing or transformed information, necessitating consideration from multiple perspectives due to its unique characteristics. In particular, vocabulary omissions and unrelated expressions in the conversation can hinder effective summarization. Therefore, in this study, we restructured by considering the characteristics of Korean conversational data, fine-tuning a pre-trained text summarization model based on KoBART, and improved conversation data summary perfomance through a refining operation to remove redundant elements from the summary. By restructuring the sentences based on the order of utterances and extracting a central speaker, we combined methods to restructure the conversation around them. As a result, there was about a 4 point improvement in the Rouge-1 score. This study has demonstrated the significance of our conversation restructuring approach, which considers the characteristics of dialogue, in enhancing Korean conversation summarization performance.

• Cross-Cultural Studies
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• v.50
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• pp.77-101
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• 2018

Even in our modern era, the projection of monsters in the recent literature contains the critical imagination of human existence for the posthuman age. The meaning of the monster-abject, especially as from the perspective of feministic criticism, contains criticism of the violent and oppressive patriarch as observed in the modern times. This article focuses on the gendered imagination of the discussions of the "abject" discussed by Julia Kristeva, and the "monstrous femine" discussed by Barbara Creed. Kim Eon-Hee's poems and Han Kang's novels, which have been examined extensively for analysis, show that the practical strategy of abject that goes beyond hate and sublime, wonder and joy through the imagination and concepts of monsters. The monster-abject strategy of Kim Eon-Hee's poem can be summarized by the narrative method of mirroring and the imagination of the truncated body. Mirroring falsification, which mimics the male speaker, is a method that some feminists strategically utilize in relation to the problem of female aversion in recent years as noted in the literature. In Kim Eon-Hee's poem, "becoming a man" and "imitating a man," through the method of mirroring appear as an image of cutting to dismantle the body. In that way, the narrative strategy of the abject that draws out abominations and bizarre effects which contains a strong critique of the patriarchal dominant ideology. The monster-abject strategy of Han-Kang's novel is embodied through the being of plants and the process of vegetarian-anorexia process. The world of the adject which was oppressed in the Han-Kang's novel, returns to the senses of the body through the symbol of the body. It is noted that the fictional characters who realize the repressed desire through the pathological symptom expressed by the female, go on to body perform active transformation. The sense of a body in a novel is not only a rejection of the world of animalman-civilization, but also a radically questioning of the noted and recognized boundaries between human beings and non-human being entities. The two writer's works show that the imagination of the monster-adject is not limited to rejecting the existing gender categories, but also goes in the direction of exploring the possibilities of various associated gender actions.