• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.9
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• pp.805-812
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• 2011

This study investigated the characteristics of heavy-weight floor impact sounds of box-frame type structure using 1:10 scale model. Ten types of floor structures(bare slabs and floating floors) were evaluated in terms of dynamic stiffness and loss factor. Floor vibrations and radiated sounds generated by simulated impact source were also measured. The results showed that the bakelite was appropriate for simulating concrete slab in the 1:10 scale model, and surface velocity and sound pressure level of concrete slab measured from the scale model showed similar tendencies with the results from in-situ in frequency domain. It was also found that dynamic behaviors of layered floor structures in the 1:10 scale model were similar to those in a real scale. Therefore, the use of 1:10 scale model would be useful for evaluating the heavy-weight floor impact sound insulation of layered floor structures when the frequency-dependent dynamic properties of each material are known.

• Journal of Community Nutrition
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• v.5 no.4
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• pp.230-238
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• 2003

Television is a powerful and persuasive teacher. It has the potential to influence perceptions, knowledge, beliefs, and behaviors, thus nutritionists need to be aware of the nutrition-related information (NRI) in television programming and the effect this information has on viewers. The purpose of this article was to review research published in peer-reviewed journals between 1988 and 2003 that examined the NRI embedded in American television programming, which is exported to over 125 nations, and its impact on nutrition knowledge, attitudes, and/or behaviors. This review revealed that, for the past 15 years, NRI was commonly included in both television advertisements and shows. Advertised foods were mainly high in fat, sodium, and/or sugar. In addition, the NRI embedded in food advertisements tended to be misleading or inaccurate. Prime-time television shows included numerous NRI containing scenes every hour, with situation comedies having the most and real-life re-enactment shows the least. Overall, low nutrient density foods accounted for approximately 40 percent or more of all food references on prime-time television shows. In television shows, foods were mostly consumed as snacks rather than meals and children often ate more nutritious foods than adults. Although relatively few studies have examined the impact of television programming on viewers, those that do exist indicate that as children watch more television, nutrition knowledge and understanding declines while misconceptions about nutrition increase. Advertising influences children's food purchase requests and subsequent purchases by adults, with the most requested and purchased foods being high in sugar, fat, and/or salt foods. Existing research indicates that television must be acknowledged as a major source of NRI and a potentially powerful influence on dietary practices.

• Journal of Environmental Impact Assessment
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• v.14 no.3
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• pp.97-107
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• 2005

The purpose of this study is to develop a system, which estimates watershed pollutant loading rate through the combination of GIS and computational mode. Also, the applicability of this study was estimated by the application of the above system for Chuncheon City. The detailed results of these studies are as follows; The pollutant loading estimation system was developed for more convenient estimation of pollutant loading rate in watershed, and the system load was minimized by the separation of estimation module for point and non-point source. This system on the basis of GIS is very economical and efficient because it can be applied to other watershed with the watershed map. System modification is not needed. The pollutant loading estimation system for point source was developed to estimate the pollutant loading rate in watershed through the extraction of the proper data from all districts and yearly data and the execution of spatial analysis which is main function of GIS. From the verification result of spatial analysis, real watershed area and the administrative districtarea extracted by spatial analysis were $1,114,893,340.15m^2$ and $1,114,878,683.68m^2$, respectively. It shows that the spatial analysis results were very exact with only 0.001% error. The pollutant loading estimation system for non-point source was developed to calculate the pollutant loading rate through the overlaying of land-use and watershed map after the construction of new land-use map using the land register database with most exact land use classification. Application result for Chuncheon City shows that the proposed system results in one percent land use error while the statistical method results in five percent. More exact nonpoint source pollutant loading was estimated from this system.

• Asia-Pacific Journal of Business
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• v.14 no.1
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• pp.295-311
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• 2023

Purpose - This study investigates how review length and sentiment impact consumers' purchase intentions, using real online reviews as the data source. The study aims to understand how the length and tone of a review affect a potential buyer's decision-making process when considering a purchase. Design/methodology/approach - A 2 (comment length: long vs. short) × 2 (comment sentiment: positive vs. negative) × 2 (product type: practical vs. hedonic) experiment was conducted. Findings - Results indicate that longer reviews have a greater impact on consumers' perceived usefulness compared to short reviews, but do not affect purchase intentions. Review sentiment is found to have a stronger impact than review length, especially for negative sentiment. The study also suggests that consumers pay more attention to reviews of practical products, and that reviews have less influence on hedonic products. Research implications or Originality - The implications of these findings are relevant for both merchants managing reviews and consumers reviewing products.The results of this research could help businesses and marketers optimize their online review strategies to maximize their impact on consumer behavior.

• Journal of information and communication convergence engineering
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• v.21 no.3
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• pp.244-251
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• 2023

Engineering or humanities data are stored in databases and are often used for search services. While the latest deep-learning technologies, such like BART and BERT, are utilized for data analysis, humanities data still rely on traditional databases. Representative analysis methods include n-gram and lexical statistical extraction. However, when using a database, performance limitation is often imposed on the result calculations. This study presents an experimental process using MariaDB on a PC, which is easily accessible in a laboratory, to analyze the impact of the database on data analysis performance. The findings highlight the fact that the database becomes a bottleneck when analyzing large-scale text data, particularly over hundreds of thousands of records. To address this issue, a method was proposed to provide real-time humanities data analysis web services by leveraging the open source database, with a focus on the Seungjeongwon-Ilgy, one of the largest datasets in the humanities fields.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.118-123
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• 2009

In this paper, we propose packet selection and significance based interval allocation algorithm for real-time streaming service. In real-time streaming of inter-frame (and layer) coded video, minimizing packet loss does not imply maximizing QoS. It is true that packet loss adversely affects the QoS but one single packet can have more impact than several other packets. We exploit the fact that the significance of each packet loss is different from the frame type it belongs to and its position within GoP. Using packet dependency and PSNR degradation value imposed on the video from the corresponding packet loss, we find each packet's significance value. Based on the packet significance, the proposed algorithm determines which packets to send and when to send them. The proposed algorithm is tested using publicly available MPEG-4 video traces. Our scheduling algorithm brings significant improvement on user perceivable QoS. We foresee that the proposed algorithm manifests itself in last mile connection of the network where intervals between successive packets from the source and to the destination are well preserved.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.6
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• pp.76-82
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• 2000

To reduce the radiated noise of ships, the noises which are generated from onboard machinery, propulsion system and transfer characteristics of structure must be identified. While the ship is operating, however, we can not directly measure each signal of inputs and characteristics of transfer passage, because measured signals are superimposed by multi source and multi transfer passage. In this paper, the signal processing method for separating noise sources and transfer functions from the measured response signal by the cepstrum technique is proposed. The proposed method is verified by application of simulated signal and impact test and shows usefulness by application of real ship test.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.311-316
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• 2004

For the location estimation in the conventional LPMS(Loose Parts Monitoring System), it is popular to employ a group delay among the acoustic sensors installed within a 3 ft range from the impact source. However, there exists inherent error in determining the arrival time differences of the generated wave group among the neighboring sensors. To overcome this problem in this study, the two dimensional approach has been proposed and applied to effectively estimate the arrival time differences by using a continuous wavelet transform which is one of the linear time-frequency analysis methods. The experiment has been performed to both the plate model and the real steam generator in a nuclear power plant. It is expected that the reliability of the location estimation could be enhanced when the proposed time-frequency method is introduced into the LPMS system.

• The Journal of the Acoustical Society of Korea
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• v.30 no.2
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• pp.92-99
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• 2011

In Japan, bang machine has been considered to have problems about not only the impact force and frequency response which are different from the real impact sources such as children's jumping and running, but also damage in the wooden structure housing. Therefore, a new impactor for lower impact force to prevent demage in wooden structure housing was developed. The impact ball was adopted as the second standard impact source in JIS A 1418-2 and ISO 140-11. In the present study, floor impact sounds generated by impact ball with drop heights in four floors of mock-up building of Building Research Institute (BRI) similar to typical Japanese wooden structure housing were investigated and also compared to jumping sound. The results show that Impact ball sound dropped at 10 cm to 30 cm was most similar to jumping sound. And The impact sound levels at 250 and 500 Hz were more sensitive to drop height than other lower frequencies. The error that may occur from the difference of height of 10 cm up and down based on the standard drop height caused by the impact ball operated by human hands was approx. 1 dB or less only in its value of characteristic, but it must be carefully taken into Impact ball in the Korea Standard.

• Journal of Power Electronics
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• v.11 no.4
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• pp.471-478
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• 2011

This paper addresses the establishment of a kVA-range plug-in hybrid electrical vehicle (PHEV) integration test platform and associated issues. Advancements in battery and power electronic technology, hybrid vehicles are becoming increasingly dependent on the electrical energy provided by the batteries. Minimal or no support by the internal combustion engine may result in the vehicle being occasionally unable to recharge the batteries during highly dynamic driving that occurs in urban areas. The inability to sustain its own energy source creates a situation where the vehicle must connect to the electrical grid in order to recharge its batteries. The effects of a large penetration of electric vehicles connected into the grid are still relatively unknown. This paper presents a novel methodology that will be utilized to study the effects of PHEV charging at the sub-transmission level. The proposed test platform utilizes the power hardware-in-the-loop (PHIL) concept in conjunction with high-fidelity PHEV energy system simulation models. The battery, in particular, is simulated utilizing a real-time digital simulator ($RTDS^{TM}$) which generates appropriate control commands to a power electronics-based voltage amplifier that interfaces via a LC-LC-type filter to a power grid. In addition, the PHEV impact is evaluated via another power electronic converter controlled through $dSPACE^{TM}$, a rapid control systems prototyping software.