• The KIPS Transactions:PartB
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• v.12B no.6 s.102
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• pp.647-654
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• 2005

In this paper, we implemented a terrestrial/cable PSIP converting system, so-called a PSIP converter, which is converting a terrestrial PSIP into a cable PSIP for a data broadcasting service in the interoperable network of terrestrial and cable, and define an interface between the PSIP converter and the OOB SI generator by using PMCP messages compliant to ATSC T3/Sl. The exiting PSIP converter just converts a terrestrial PSIP into a cable PSIP compliant to ATSC and OCAP standard and transmits by a MPEG-2 TS format. That is to say, it is not for the digital data broadcasting but for the digital broadcasting. In addition, the PSIP converter can support various types of PSIP information to the OOB SI generator by using PMCP messages defined by a hierarchical structure as per each channel, audio/video event, data event and so on.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.8
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• pp.957-965
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• 1999

그룹간 공동 작업이나 화상 회의와 같은 그룹 통신의 수요가 늘어나면서 멀티캐스팅을 이용한 효율적인 데이타 전송에 대한 요구가 증가하고 있다. 특히 오디오나 비디오 데이타와는 달리 공동 문서 작업이나 그룹간 문서 전송을 위한 데이타 처리를 위해서는 어느 정도의 시간 손실이 있더라도 신뢰성을 보장할 수 있는 멀티캐스트 프로토콜이 요구된다. 그러나 멀티캐스트 전송에서의 신뢰성을 보장하기 위하여 손실 패킷에 대한 재전송 패킷이 전체 그룹으로 멀티캐스트 되는 것은 네트워크 상에 트래픽을 폭증시키는 요인이 된다. 이에 본 논문에서는 지역 그룹에서의 오류 회복을 위한 재전송 제한 기법을 제안하여 손실 패킷의 재전송 과정에서 발생하는 트래픽의 폭주를 제어하고자 한다. 이것은 재전송 패킷이 중복없이 다중 수신자에게 전송될 수 있도록 하여 그룹 내의 재전송 패킷의 양을 줄이고 필요없는 중복 패킷이 네트워크의 효율을 저하시키는 것을 방지하고자 하는 데 그 목적이 있다. Abstract As the size and the geographic span of communication groups increases, efficient data transmission schemes using Multicast service become more and more essential. Especially, unlike audio and video applications, for some collaborative applications and other data delivery components which require ordered and lossless delivery of data, Reliable Multicast Service is needed to ensure consistent presentation across multiple views. Thus error recovery by retransmission of loss data is provided in order to guarantee the reliability of multicast transmission protocol. However, redundant retransmission packets by multicast may cause traffic implosion on the Internet and it can be aggravated with continuous retransmission.This paper describes a Restricted Retransmission Mechanism as an error recovery method of multicast service in a local group, which can handle traffic implosion in retransmission process. It reduces redundant retransmission packets flowing into a local group and supports reliable multicast transmission. The goal of this mechanism is to reduce retransmission packets and decrease the load for group members and networks.

• 한국지구물리탐사학회:학술대회논문집
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• 2005.05a
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• pp.281-286
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• 2005

This paper presents sensitivity analysis of generalized rapid relaxation inversion (GRRI) algorithm for inverting controlled-source audio-frequency magnetotelluric (CSAMT) data. The algorithm was originally developed by modifying the RRI algorithm to recover a two-dimensional (2-D) conductivity structure of the Earth from MT data, but can be extended to include CSAMT data if it is combined with 2.5-D forward modeling. These GRRI approximate sensitivities are validated by comparison with exact 1-D and 2.5-D sensitivities. The comparison shows that the GRRI sensitivity is a good approximation to the exact sensitivity and has about half magnitude of the RRI sensitivity. Although the magnitude of the GRRI sensitivity is still slightly larger than that of the 2.5-D sensitivity, both sensitivities are broadly similar in shape when source-receiver offsets are greater than one skin depth on the Earth.

• Journal of Broadcast Engineering
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• v.11 no.4 s.33
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• pp.541-553
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• 2006

Since DMB on-air was started, not high-qualified audio, video services but various service models have been required. This paper is about systems for one of these services, video associated data service. A terrestrial DMB system to make contents of video associated data services and transmit them on DMB channel is proposed in this paper. This system satisfies standard of the video associated data services for terrestrial DMB; MPEG-4 BIFS (BInary Format for Scene) Core2D scene description profile and graphics profile. This system is designed to support two major features of broadcasting, real-time authoring non automatic transmission and non real-time authoring automatic transmission, and focuses on the abilities to make high-qualified contents efficiently and transmit them to video encoder reliably. This system proved its performance through conformance tests with various receivers, so can be used in future on-air.

• Geophysics and Geophysical Exploration
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• v.6 no.2
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• pp.64-70
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• 2003

A new approach of estimating the coefficient of permeability (COP) from resistivity has been developed, which can provide another good application tool of geophysical methods to geo-technical field. Borehole electrical logging and Lugeon test results in Yangsan area showed that resistivity is inversely proportional to the COP. For granite and andesite in Yansan area, the relation between the resistivity ($\rho$) and the COP (k) revealed that, $log(k){\approx}-0.85621\;log({\rho})+0.0031$. Derived relation is applied to AMT data acquired from a survey line along the tunnel. Two-dimensional resistivity distribution from AMT data was converted to two-dimensional COP section. The final COP section can be used as good input data for groundwater modeling.

• Nuclear Engineering and Technology
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• v.44 no.8
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• pp.897-910
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• 2012

Inappropriate communications can cause a lack of necessary information exchange between operators and lead to serious consequences in large process systems such as nuclear power plants (NPPs). In this regard, various kinds of taxonomies of inappropriate communications have been developed to prevent inappropriate communications. However, there seems to be difficult to identify inappropriate communications from verbal protocol data between operators. Because the existing taxonomies were developed for use in report analysis, there is a problem of 'uncertainty'. In consequence, this paper proposes a new taxonomy of inappropriate communications and provides some insights to prevent inappropriate communications. In order to develop the taxonomy, existing taxonomies for four industries from 1980 to 2010 were collected and a new taxonomy is developed based on the simplified one-way communication model. In addition, the ratio of inappropriate communications from 8 samples of audio-visual format verbal protocol data recorded during emergency training sessions by operating teams is compared with performance scores calculated based on the task analysis. As a result, inappropriate communications can be easily identified from the verbal protocol data using the suggested taxonomy, and teams with a higher ratio of inappropriate communications tend to have a lower performance score.

• Journal of Internet Computing and Services
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• v.3 no.2
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• pp.15-26
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• 2002

Since multimedia data such as video and audio data are displayed within a certain time constraint, their computation and manipulation should be handled under limited condition. Traditional real-time scheduling algorithms could net be directly applicable, because they are not suitable for multimedia scheduling applications which support many clients at the same time. Rate Regulating Proportional Share Scheduling Algorithm is a scheduling algorithm considered the time constraint of the multimedia data. This scheduling algorithm uses a rate regulator which prevents tasks from receiving more resource than its share in a given period. But this algorithm loses fairness, and does not show graceful degradation of performance under overloaded situation, This paper proposes a new modified algorithm. namely Modified Proportional Share Scheduling Algorithm considering the characteristics of multimedia data such as its continuity and time dependency, Proposed scheduling algorithm shows graceful degradation of performance in overloaded situation and the reduction in the number of context switching, Furthermore, a new evaluation method is proposed which can evaluate the flexibility of scheduling algorithm.

• Journal of Broadcast Engineering
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• v.12 no.3
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• pp.203-213
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• 2007

DMB video/audio service was successfully launched. DMB data service is a matter of primary concern now. The TTI(Traffic and Travel Information) service is considered as a killer application of the data service. Tn this paper, we propose a method for design and implementation of the broadcasting system for TTI service. The proposed TTI service system consists of an authoring tool, the DB module, the Transmission module and Monitoring module. This system satisfies the national TTA standards of the Traffic and Travel Information data services for terrestrial DMB; TPEG(Transport Protocol Experts Group) platform. The system was designed to support real-time automatic transmission for CTT and CTT SUM, and non real-time authoring & automatic transmission for POI and SDI, and was focused on the capability to make high-quality contents efficiently and to send them to the data inserter reliably. The performance of the implemented system was proven through the conformance tests with the various commercial receivers. After the continuous upgrade, the system is being used in commercial service.

• Journal of Korean Academy of Nursing
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• v.49 no.6
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• pp.677-689
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• 2019

Purpose: This qualitative study aimed to develop a substantive theory of the process of adaptation to motherhood in Central Asian-Korean immigrants to Korea. Methods: Individual, in-depth interviews were conducted from July to September 2017, with 18 women who emigrated of Korean ethnicity from Central Asia to Korea, and took care of their baby for at least a year after their first delivery in Korea. The interviews were audio-recorded and transcribed verbatim. Data from the transcriptions were analyzed through Strauss and Corbin's grounded theory method, and data analysis was conducted simultaneously with data collection. Results: As a result of categorizing the interview data through the process of open coding, 10 categories, with 31 subcategories and 102 concepts were drawn, and "growth as a Central Asian-Korean mother in an unfamiliar, historical hometown" was found to be the core category of the process of adaptation to motherhood in Central Asian-Korean immigrants to Korea. Conclusion: A characteristic of the process of adaptation to motherhood in Central Asian-Korean immigrants to Korea, drawn from this study, is that it differs according to the level of initiative to carry out interaction strategies, and the use of various supportive social resources. The findings indicate the need for Medicare eligibility adjustment for antenatal care, the extension of the visa renewal period during childbirth, the development of web- or mobile application-based educational programs in Russian language, and the establishment of integrated visiting healthcare services, community service resources, and policy support to enable these women to utilize various supportive social resources.

• The Transactions of the Korea Information Processing Society
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• v.4 no.5
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• pp.1172-1181
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• 1997

A militimedia data is a data mixed of formatted data like an audio and video. Multimedia data has characteristics that it need large amount of storage,wide network bandwith andreal time responsibolity. Because of these characteristocs, the VOD server and continous media storage server have a disk stripe structure or disk stripe sructure or disk array structure(RAID).In the parallel disk access system,high-speed play-back of continous media using segment interleavung may not ensure Qos pf other cioents because of the concentrated load within some disks. The load concentration of disks is related to both the number of disks in the system and playback rate of contimous media.In this paper. we describe that high-speed playback scheme,which is independent of the number of disk and plyback rate can be achieved by technique of changing the in-teval of access to segnent location.We show the experimental result of this technique in this pater.