• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.1
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• pp.54-63
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• 2005

Detection ranges of acoustic instruments mainly used for fisheries and their research are derived as the range bordered by a certain signal-to-noise ration (SNR) thershold. The SNR is depicted by several factors on transmitting and receiving, sound propagation, scattering by objects, and mainly self-ship noise. The detection ranges are shown for several fisheries instrument, such as echo sounder, quantiative echo sounder, and bio-telemetry system. The results can be used for designing the instruments, examining the capability of user's own instruments, and interpreting obtained data or echograms. Increasing transmitting power is not as effective for high frequencies as for low frequencies to increase the detection range. Comparison of volume backscattering strengths obtained by the quantitative echo sounder at several frequencies should be done within the same detection range. By applying the concept of the detection range for the bio-telemetry receiver beams, the number of the beams and the beamwidths can be determined.

• International Journal of Internet, Broadcasting and Communication
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• v.16 no.2
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• pp.10-21
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• 2024

Recently, audio systems are changing the configuration of conventional sound reinforcement (SR) systems and public address (PA) systems by using audio over IP (AoIP), a technology that can transmit and receive audio signals based on internet protocol (IP). With the advancement of IP technology, AoIP technologies are leading the audio market and various technologies are being released. In particular, audio networks and control hierarchy over peer-to-peer (Anchor) technology based on AoIP is a system that transmits and receives audio signals over a wide bandwidth without an audio mixer, creating a novel paradigm for existing audio system configurations. Anchor technology forms an audio system by connecting audio sources and output equipment with On-site audio center (OAC), a device that can transmit and receive IP. Anchor's receiving OAC is capable of receiving and mixing audio signals transmitted from different IPs, making it possible to configure a novel audio system by replacing the conventional audio mixer. However, Anchor technology does not have the ability to provide audio effects to input devices such as microphones and instruments in the audio system configuration. Due to this, when individual control of each audio source is required, there is a problem of not being able to control the input signal, and it is impossible to individually affect a specific input signal. In this paper, we implemented a tone control module that can individually control the tone of the audio source of the input device using the audio processor core in the audio system based on Anchor technology, tone control for audio sources is possible through a tone control module connected to the transmitting OAC. As a result of the study, we confirmed that OAC receives the signal from the audio source, adjusts the tone and outputs it on the tone control module. Based on this, it was possible to solve problems that occurred in Anchor technology through transmitting OAC and tone control modules. In the future, we hope that the audio system configuration using Anchor technology will become established as the standard for audio equipment.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.1
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• pp.16-24
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• 2011

The sound speed of seawater can be calculated by the empirical formula as a function of temperature, salinity and pressure. It is little affected by salinity because the average salinity is 34 psu and varies within a few psu seasonally and spatially in the ocean. Recently, low-salinity water of 24 psu flows into the western sea area of Jeju Island due to the flood of the Yangtze River in China during summer, affecting sound speed profile. In this paper, it was analyzed how environmental changes affected to the underwater communication - the sound speed of low-salinity water was calculated, and the communication channel was estimated by the simulated acoustic rays while the transmitting and receiving depth and the range were varied with and without the low-salinity layer. And The BER (Bit error rate) was calculated by BPSK(Binary phase shift key) modulation and the effects of the low-salinity water on the BER was investigated. The sound speed profile was changed to have positive slope by the low-salinity layer at the sub-surface up to 20 m of depth, forming acoustic wave propagation channel at the sub-surface resulting in the decrease of most of the BER Consequently, this paper suggests that it is important to consider changes of the ocean environment for correctly analyzing the underwater communication and the detection capability.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.4
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• pp.1013-1023
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• 2016

Transborder data flow(TBDF) of personal information in Korea has been limited by current Privacy law which request data subject to give consent. As the IT industry is growing at an incredible rate, there is a need to review the existing law to cope with growing industrial demand and increasing numbers of international data transfer. The transfer of personal data overseas not only allow businesses providing IT services including finance, internet, e-commerce to thrive, but also impact every aspect of our lives which are increasingly depended on these technology. Transmitting personal data across borders raises serious questions of privacy protection and restriction of business operation. In ordrer to promote interoperability of personal data in international environment, a considerable amount of research and debate needs to be taken before implementing a sound policy. This paper presents a need for a sound TBDF policy in Korea by examine the main policy challenges associated with TBDF. Finally, the paper identify policy suggestions based on European Union's approach as they have successfully implemented TBDF policy that balanced data privacy and economic agenda.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.2135-2140
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• 2015

In this paper, proposed a new lighting control system which can reduce power consumption compared to conventional street lamps and intelligently control the light efficiently depending on whether there is a vehicle on the street. The new lighting control system proposed by this paper detects the presence of cars by collecting and analyzing sounds generated by the movement of cars. Then, the system controls lighting of street lamps based on the above car detection information, and turns on the street lamps sequentially by transmitting the car detection information. Experimental results showed that lightings were controlled based on the presence of cars and that operations of the lamps were made by turning on the lights sequentially by determining the moving direction of cars. This system is considered a technology that can reduce energies by applying to local roads with a few cars moving or national highways where lights are always turned on with low energy efficiency.

• The Journal of the Acoustical Society of Korea
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• v.36 no.3
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• pp.179-185
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• 2017

The problem that occurred in the design/fabrication/testing of the wideband transmitting power amplifier for an embedded active SONAR (Sound Navigation and Ranging) system operating underwater was analyzed and the solution of the problem was proposed in this paper. Wideband acoustic SONAR systems had been developed in order to improve the underwater detection performance. The underwater acoustic transmission system had been also developed to achieve the wideband SONAR system. In this paper, the wideband acoustic transmission signal was generated using a 2 Level sawtooth type Class D PWM (Pulse Width Modulation) which was not complicated to implement. When the sonar signals having two or more frequencies were simultaneously generated, parasitic frequencies were added to the original signals by integer multiples of the frequency difference of the original signal. To cope with this problem, we proposed a way to remove the parasitic frequency from the source signal through modeling and simulation of the implemented power amplifier and PWM control hardware using MATLAB and Simulink.

• Journal of Digital Contents Society
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• v.6 no.1
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• pp.89-94
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• 2005

In machine translation the goal of natural language generation is to produce an target sentence transmitting the meaning of source sentence by using an parsing tree of source sentence and target expressions. It provides generator with linguistic structures, word mapping, part-of-speech, lexical information. The purpose of this study is to research the Korean Characteristics which could be used for the establishment of an algorism in speech recognition and composite sound. This is a part of realization for the plan of automatic machine translation. The stage of MT is divided into the level of morphemic, semantic analysis and syntactic construction.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1658-1660
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• 2000

Simple signs were usually exchanged as the means of underwater communications. As people recently, need more informations for underwater activities, necessities of underwater communication systems exchanging hunman voice are increased. The purpose of this paper is understanding the ordinary characteristics of underwater communication and investigating the necessary conditions for a good underwater communication system by making a basic communication module. The experiment is achieved by applying AM (Amplitude Modulation) which is mainly used for the underwater communication systems and using common ultrasonic transducers. Ultrasonic transducers usually have narrow bandwidth for transducing electrical energy to mechanical energy. For improvement of sound reconstruction, transducers need more bandwidth which covers voice's frequency range, and goof linearity characteristics in this frequency range. As underwater transmissions have many factors to distort signals. Amplitude Modulation is not a proper way for underwater communications. Using digital signal by sampling human voice should be a good way for this systems, because digital communication simplify transmitting signals.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.4
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• pp.328-336
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• 2004

Recently a mobile service is changing into a system environment that offers the customer various contents service. Representative example of service is a Calling Identity Del ivory Service(CID). Such service has the problem in the case which the receiver cannot remember the phone number of the sender; it has a difficult problem that cannot easily confirm whose the phone number it is. Therefore, it is desirable to design and implement visual services that can enhance the recognition of users. In this paper, we propose the architecture that is similar to a Calling Identity Delivery Service. We propose the architecture for communication service and system that is able to visually display the information of the sender using 2D image data in mobile environment. After that we set the image information to represent the user and this method is able to visually display the information of the sender by transmitting an image data through channels from switch station or base station using the server. When the receiver receives a phone call from the sender, this method provides an efficient service by transmitting visual data with bell sound. That is, the image information of sender is appeared on liquid crystal display(LCD) of the receiver at the same time. We investigate the concepts for processing real-time transmission of image data and describe an example of the implementation result that is based on system. This technology has a potential influence on the marketing and presents an efficiency of this method.

• Hwankyungkyoyuk
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• v.18 no.2 s.27
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• pp.76-89
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• 2005

The objectives of this study are to identify the environmental consumer behavior, to examine the degree of environmental consumer behavior of the junior high school students, and to investigate the educational system of a school which influence the consumer behavior. The data used in this study are 368 male and female students in 9th grade in Anyang City, Kyunggi-do province. Statistics used for data analysis are means, standard deviation, t-test, and Multiple Regression Analysis. The results of the research are summarized as follows : First of all, as a tendency of the environmental consumer behavior of junior high students, the primary factor to the environmental problems was media, and among those, TV and radio was the medium to environmental problems. This implies the fact that the time juveniles interact with mass media is significantly growing, which means that transmitting environmental problems by programs targeted to adolescences through mass media would be effective. Next, the disposal process showed the highest environmental consumer behavior, followed by the consuming and purchasing process. Education on the purchasing process will be necessary to encourage environmental consumer behavior. The route of obtaining environmental knowledge was basically from school and the level of the average environmental knowledge fumed out to be low. This shows the need to produce and distribute media education materials because educating the conclusion of actual experiments will be more effective than that of theoretical studies. The conformity showed general indifference on environmental consumer behavior and the environmental resources were normally collected seperated. Conformity is a cultural bond teenagers think important, therefore education available for students about the same age should be developed. Next, the value intention of the surveyed showed that the ecological intention was highest, followed by economic and convenience intentions. This means the morale of the junior high students to environmental consumer behavior is set sound. Females tended to act more environmentally, while males showed more intention to economic causes. Also, the students of the boys-only or girls-only schools showed higher environmentally sound behavior in disposal processes. Finally, the environmental consumer behavior was influenced most by environmental consumer behavior of the conformity group, followed by ecological morale, frequency of encountering environmental problems, gender, environmental knowledge, whether the school was boys-only or girls-only or not, economical morale, respectively. The largest factor affecting the consumer activity of the purchase, consumption, and disposal process was environmental consumer behavior of the conformity group, along with the ecological morale, and the frequency of encountering environmental problems. This implies that conformity group is a large factor to the juveniles and a plan to entice the environmental consumer behavior of conformity groups are necessary.