• The Journal of the Acoustical Society of Korea
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• v.41 no.1
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• pp.52-57
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• 2022

Speech consists of the sum of complex sine-waves. This study investigated the perception of electrical hearing by applying the sinusoidal model to cochlear implant simulation. Fourteen adults with normal hearing participated in this study. The sentence recognition tests were implemented using the sentence lists processed by the sinusoidal model which extracts 2, 4, 6, 8 sine-wave components and sentence lists processed by the same sinusoidal model along with cochlear implant simulation (8 channel vocoders). The results showed lower speech recognition for the sentence lists processed by the sinusoidal model and cochlear implant simulation compared to those by the sinusoidal model alone. Notably, the lower the number of sine-wave components (2), the larger the difference was. This study provides the perceptual pattern of sine-wave speech for electrical hearing by cochlear implant listeners, and basic data for development of speech processing algorithms in cochlear implants.

• Geophysics and Geophysical Exploration
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• v.26 no.3
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• pp.103-113
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• 2023

In the oil and gas exploration market, various cableless seismic systems have been developed as an alternative to improve data acquisition efficiency. However, developing such equipment at a small scale for academic research is not available owing to highly priced commercial products. Fortunately, building and experimenting with open-source hardware enable the academic utilization of cableless seismic equipment with relatively low cost. This study aims to develop a cableless seismic acquisition module using Arduino. A cableless seismic system requires the combination of signal sensing, simple pre-processing, and data storage in a single device. A conventional geophone is used as the sensor that detects the seismic wave signal. In addition, it is connected to an Arduino circuit that plays a role in implementing the processing and storing module for the detected signals. Three main functions are implemented in the Arduino module: preprocessing, A/D conversion, and data storage. The developed single-channel module can acquire a common receiver gather from multiple source experiments.

• Journal of the Korea Society of Computer and Information
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• v.14 no.2
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• pp.181-190
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• 2009

This paper presents a multimodal emergency recognition system based on visual information, audio information and gravity sensor information. It consists of video processing module, audio processing module, gravity sensor processing module and multimodal integration module. The video processing module and gravity sensor processing module respectively detects actions such as moving, stopping and fainting and transfer them to the multimodal integration module. The multimodal integration module detects emergency by fusing the transferred information and verifies it by asking a question and recognizing the answer via audio channel. The experiment results show that the recognition rate of video processing module only is 91.5% and that of gravity sensor processing module only is 94%, but when both information are combined the recognition result becomes 100%.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.3
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• pp.59-64
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• 2023

Fire and disaster broadcasting systems are divided into analog, digital, and network-based digital public address systems, and important specifications in network-based digital public address systems are low-latency audio, high sampling rate, and multi-channel input and output. In the past, it has been widely used to the AoE method for distinguishing based on the MAC address of the data link layer. However, this method has a problem of increasing complexity and cost. This proposal is an AoIP/UDP method, which allows communication to be easily distinguished by IP address without the need for a separate redundant network, so that the network can be freely used and configured, and cost can be reduced by reducing complexity. After implementing the AoIP/UDP method, the experimental results showed that the cost was improved with the equivalent performance with 2.66ms latency.

• The Journal of the Acoustical Society of Korea
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• v.41 no.2
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• pp.192-198
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• 2022

As an effective weapon system for anti-submarine warfare, DIrectional Frequency Analysis and Recording (DIFAR) sonobuoy detects underwater targets via beamforming with three channels composed of an omni-direcitonal and two directional channels. However, ambient noise degrades the detection performance of DIFAR sonobouy in specific direction (0°, 90°, 180°, 270°). Thus, an ambient noise redcution technique is proposed for performance improvement of acoustic target detection of DIFAR sonobuoy. The proposed method is based on OTA (Order Truncate Average), which is widely used in sonar signal processing area, for ambient noise estimation and Wiener filtering, which is widely used in speech signal processing area, for noise reduction. For evaluation, we compare mean square errors of target bearing estmation results of conventional and proposed methods and we confirmed that the proposed method is effective under 0 dB signal-to-noise ratio.

• Journal of the Korea Society of Computer and Information
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• v.28 no.12
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• pp.1-7
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• 2023

The advent of deep learning technologies has led to the development of various medical applications, making healthcare services more convenient and effective. Among these applications, heart rate estimation is considered a vital method for assessing an individual's health. Traditional methods, such as photoplethysmography through smart watches, have been widely used but are invasive and require additional hardware. Recent advancements allow for contactless heart rate estimation through facial image analysis, providing a more hygienic and convenient approach. In this paper, we propose a lightweight methodology capable of accurately estimating heart rate in mobile environments, using a specialized 2-channel network structure based on 2D convolution. Our method considers both subtle facial movements and color changes resulting from blood flow and muscle contractions. The approach comprises two major components: an Encoder for analyzing image features and a regression layer for evaluating Blood Volume Pulse. By incorporating both features simultaneously our methodology delivers more accurate results even in computing environments with limited resources. The proposed approach is expected to offer a more efficient way to monitor heart rate without invasive technology, particularly well-suited for mobile devices.

• Journal of Korean Classical Literature and Education
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• no.39
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• pp.137-180
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• 2018

This article examines the constitutional characteristics of the works in the "Shinbi Apartment" (Mysterious Apartment) series produced by Tooniverse, a domestic animation channel, and considers the meaning of the contents of the ghoststory (鬼神談). The "Shinbi Apartment" series is a horror animation for children. It was produced for the first time in Korea and recorded high ratings. Additionally, it is different from Japanese horror animations that were dubbed and broadcast in Korea in terms of composition and narrative direction, and it succeeds in the form and direction of the traditional Korean ghost story. "Shinbi Apartment - The Secret of Ghost Ball" enriches narrative stories by embracing the structure of the "female ghost story" in traditional ghost stories while following the form of ghosts that suddenly pop up in the daily routines of contemporary ghost stories. The ghost's shape, which has a bizarre and unpredictable aspect, embodies the ghost as the object of fear that modern horror stories intend. However, it does not stop there, but puts the attention on the hero who focuses on the emerging ghost and listens and communicates with it, placing the emphasis of the story on communication, understanding, forgiveness, and reconciliation. The structure and contents of the unique story of "The Secret of Ghost Ball" contribute to the transformation of the ghost into a subject of friendliness and entertainment, not merely as one of shock, fear, and anxiety. Additionally, as the concept of "child" is being created, the custom of modernity, which deals with the story of ghosts in the dimension of teaching and edification, is also manifested in "The Secret of Ghost Ball." In other words, through the figure of the devil, it is to continue the lesson of the story by revealing the adventure, the courage necessary for the "child," and the boundaries for substance and appearance. The "Shinbi Apartment" series has also contributed to the success of ghosts as commercial contents. The structure of the story and its characters have been actively used as educational tools and toys for children. It can be said that ghost culture contributed to this popularization by establishing a base for enjoying ghosts for amusement and entertainment.

• Journal of Astronomy and Space Sciences
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• v.20 no.2
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• pp.109-122
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• 2003

To examine the causal relationship between geomagnetic storm and substorm, we investigate the correlation between dispersionless particle injection rate of proton flux observed from geosynchronous satellites, which is known to be a typical indicator of the substorm expansion activity, and Dst index during magnetic storms. We utilize geomagnetic storms occurred during the period of 1996 ~ 2000 and categorize them into three classes in terms of the minimum value of the Dst index ($Dst_{min}$); intense ($-200nT{$\leq$}Dst_{min}{$\leq$}-100nT$), moderate($-100nT{\leq}Dst_{min}{\leq}-50nT$), and small ($-50nT{\leq}Dst_{min}{\leq}-30nT$) -30nT)storms. We use the proton flux of the energy range from 50 keV to 670 keV, the major constituents of the ring current particles, observed from the LANL geosynchronous satellites located within the local time sector from 18:00 MLT to 04:00 MLT. We also examine the flux ratio ($f_{max}/f_{ave}$) to estimate particle energy injection rate into the inner magnetosphere, with $f_{ave}$ and $f_{max}$ being the flux levels during quiet and onset levels, respectively. The total energy injection rate into the inner magnetosphere can not be estimated from particle measurements by one or two satellites. However, the total energy injection rate should be at least proportional to the flux ratio and the injection frequency. Thus we propose a quantity, “total energy injection parameter (TEIP)”, defined by the product of the flux ratio and the injection frequency as an indicator of the injected energy into the inner magnetosphere. To investigate the phase dependence of the substorm contribution to the development of magnetic storm, we examine the correlations during the two intervals, main and recovery phase of storm separately. Several interesting tendencies are noted particularly during the main phase of storm. First, the average particle injection frequency tends to increase with the storm size with the correlation coefficient being 0.83. Second, the flux ratio ($f_{max}/f_{ave}$) tends to be higher during large storms. The correlation coefficient between $Dst_{min}$ and the flux ratio is generally high, for example, 0.74 for the 75~113 keV energy channel. Third, it is also worth mentioning that there is a high correlation between the TEIP and $Dst_{min}$ with the highest coefficient (0.80) being recorded for the energy channel of 75~113 keV, the typical particle energies of the ring current belt. Fourth, the particle injection during the recovery phase tends to make the storms longer. It is particularly the case for intense storms. These characteristics observed during the main phase of the magnetic storm indicate that substorm expansion activity is closely associated with the development of mangetic storm.

• The Journal of Society for e-Business Studies
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• v.13 no.3
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• pp.1-20
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• 2008

Today's computing environment which is getting distributed to communicate with various systems needs dynamic inter-connectivity of the systems. MOM(Message Oriented Middleware) is popularly used for transmitting XML messages among the distributed systems for the inter-connectivity. But, they do not support event-based message routing functionalities with XML transformation for processing effective message routing, which is essential to inter-connectivity, and there is no integrated platform to cope with these requirements. Although event-based message routing and XML transformation have been studied in a wide range of computer science areas, development of message routing systems is considered as a tough job due to the technological difficulties. In order to address these requirements, we proposed a novel system, named RMRS(Rule-based Message Routing System), which supports event-based message routing as well as XML message transformation. To make the proposed system easy to use, we also redesigned ECA(Event- Condition-Action) rule to fit in our system and developed a tool to map source XML structure into target XML structure.

• Science of Emotion and Sensibility
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• v.20 no.2
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• pp.73-86
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• 2017

The purpose of this study was to investigate the influence of consumers' shopping value(SV), ease of use(EOU), and usefulness(U) on their purchase intention(PI) in mobile shopping mall. Path hypotheses in structural equation model which was constructed for this purpose were verified. In addition, the research model was analyzed according to the groups classified by the level of purchase experience in mobile shopping mall. The survey was limited to the respondents in their 20s and 30s living in Seoul and other metropolitan areas who had purchased fashion products in mobile shopping mall. 411 useful data collected from on-line survey were analyzed by descriptive statistics, exploratory factor analysis, confirmatory factor analysis, reliability analysis, and pearson's correlation analysis using SPSS 21 and AMOS 19. The results of verifying the hypotheses were as follows: First, SV was composed of two factors which included hedonic shopping value(HSV) and utilitarian shopping value(USV). Second, the research model was verified as an acceptable model in explaining the influence of consumers' SV, EOU, and U on PI. Third, seven hypotheses among nine hypotheses were accepted in high purchasers. HSV did not have a significant influence on PI, and EOU did not affect PI significantly. Fourth, five hypotheses were accepted in light purchasers. HSV affected U significantly while USV had a significant impact on EOU and PI. EOU affected U, and U affected PI significantly. In conclusion, USV was proven to be the factor affecting PI directly as well as indirectly. Eou and U also had a significant influnce on PI in mobile fashion shopping. These results will provide mobile marketers with the differentiated strategies to make consumers lead to mobile purchase.