• Title/Summary/Keyword: stream service

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Classification and Characterization for Water Level Time Series of Shallow Wells at the National Groundwater Monitoring Stations (국가지하수관측소 충적관측정의 수위 변동 유형 분류 및 특성 비교)

  • Kim, Gyoo-Bum;Yum, Byoung-Woo
    • Journal of Soil and Groundwater Environment
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    • v.12 no.5
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    • pp.86-97
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    • 2007
  • The principal component analysis was performed to identify the general characteristics of groundwater level changes from 202 deep and 112 shallow wells monitoring data, respectively, which came from the National Groundwater Monitoring Stations operated by KWATER with time spans of 156 continuous weeks from 2003 to 2005. Eight principal components, which accounted for 80% of the variability of the original time series, were extracted for water levels of shallow and deep monitoring wells. As a result of cluster analysis using the loading value of three principal components for shallow wells, shallow monitoring wells were divided into 3 groups which were characterized with a response time to rainfall (Group 1: 4.6 days, Group 2: 24.1 days, Group 3: 1.4 days), average long-term trend of water level (Group 1: $2.05{\times}10^{-4}$ m/day, Group 2: $-7.85{\times}10^{-4}$ m/day, Group 3: $-3.51{\times}10^{-5}$ m/day) and water level difference (Group 1 < Group 2 < Group 3). Additionally, they showed significant differences according to a distance to the nearest stream from well (Group 3 < Group 2 < Group 1), topographic slope of well site (Group 3: plain region, Group 1: mountainous region) and groundwater recharge rate (Group 3 < Group 2 < Group 1) with a p-value of 0.05.

Voice Packet Processing Scheme for Voice Quality and Bandwidth Efficiency in VoIP (VoIP의 음성품질/대역효율 개선을 위한 음성패킷 처리)

  • Kim, Jae-Won;Sohn, Dong-Chul
    • Journal of Korea Multimedia Society
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    • v.7 no.7
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    • pp.896-904
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    • 2004
  • In this paper, We present an efficient variable rate speech coder for spectral efficiency and packet processing technique for packet loss compensation of a voice codec with 10msec frame in VoIP service. Through disconnecting the users from the spectral resource during silence interval of about 60% period, a variable rate voice coder based on a voice activity detection(VAD) can increase spectral gain by two times. The performance of the method was analyzed by variation of detected voice activity factor and degraded speech frame ratio under various background noise level, and compared those of G.729B of ITU-T 8kbps standard speech codec. A method to compensate lost packets utilized addition of recovery data to a main stream and error concealment scheme for speech quality enhancement, the performance is verified by reconstructed speech quality. The proposed scheme can achieve spectral gain by two times or enhance speech quality by 3dB through reserved bandwidth of VAD. Therefore, the proposed method can enhance a spectral efficiency or speech quality of VoIP.

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Regional Trend Analysis for Groundwater Quality in Jeju Island - Focusing on Chloride and Nitrate Concentrations - (제주도 지하수 수질의 광역적 추세 특성 분석 - 염소 및 질산성질소를 대상으로 -)

  • Kim, Gyoo-Bum;Kim, Ji-Wook;Won, Jong-Ho;Koh, Gi-Won
    • Journal of Korea Water Resources Association
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    • v.40 no.6 s.179
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    • pp.469-483
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    • 2007
  • Nitrate and chloride are the most common contaminants in groundwater and their concentrations increase easily due to fertilizer consumption and urbanization. The number of time series data for groundwater quality at a single site was not sufficient to analyze trends on Jeju Island. Therefore rectangle grids were drawn for the whole island and single grid was determined to be $500m{\times}500m$ after considering similar stream density, homogeneous hydraulic coefficients, geologic features of volcanic rock and low topographic slopes. All data within each lattice were collected and arranged in time series order and analyzed using Sen's method. 10.6 % of the total lattices for chloride and 22.4% for nitrate showed upward trends from the early 1990's to the early 2000's. Especially, upward trends for nitrate concentration are distinct in the low mid-mountainous areas of western and southern watersheds. Many septic tanks and much domestic waste from the urbanization of the low mid-mountainous area have produced this upward trend. Additionally, the agricultural region has dramatically increased since the 1990's and this has led to an increase of fertilizer consumption and, as a result, nitrate concentration. Therefore, the target of any management plan for groundwater quality on Jeiu Island needs to be focused on careful land use decisions in the mid-mountainous areas which are near Halla Mountain.

The Big Data Analytics Regarding the Cadastral Resurvey News Articles

  • Joo, Yong-Jin;Kim, Duck-Ho
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.6
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    • pp.651-659
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    • 2014
  • With the popularization of big data environment, big data have been highlighted as a key information strategy to establish national spatial data infrastructure for a scientific land policy and the extension of the creative economy. Especially interesting from our point of view is the cadastral information is a core national information source that forms the basis of spatial information that leads to people's daily life including the production and consumption of information related to real estate. The purpose of our paper is to suggest the scheme of big data analytics with respect to the articles of cadastral resurvey project in order to approach cadastral information in terms of spatial data integration. As specific research method, the TM (Text Mining) package from R was used to read various formats of news reports as texts, and nouns were extracted by using the KoNLP package. That is, we searched the main keywords regarding cadastral resurvey, performing extraction of compound noun and data mining analysis. And visualization of the results was presented. In addition, new reports related to cadastral resurvey between 2012 and 2014 were searched in newspapers, and nouns were extracted from the searched data for the data mining analysis of cadastral information. Furthermore, the approval rating, reliability, and improvement of rules were presented through correlation analyses among the extracted compound nouns. As a result of the correlation analysis among the most frequently used ones of the extracted nouns, five groups of data consisting of 133 keywords were generated. The most frequently appeared words were "cadastral resurvey," "civil complaint," "dispute," "cadastral survey," "lawsuit," "settlement," "mediation," "discrepant land," and "parcel." In Conclusions, the cadastral resurvey performed in some local governments has been proceeding smoothly as positive results. On the other hands, disputes from owner of land have been provoking a stream of complaints from parcel surveying for the cadastral resurvey. Through such keyword analysis, various public opinion and the types of civil complaints related to the cadastral resurvey project can be identified to prevent them through pre-emptive responses for direct call centre on the cadastral surveying, Electronic civil service and customer counseling, and high quality services about cadastral information can be provided. This study, therefore, provides a stepping stones for developing an account of big data analytics which is able to comprehensively examine and visualize a variety of news report and opinions in cadastral resurvey project promotion. Henceforth, this will contribute to establish the foundation for a framework of the information utilization, enabling scientific decision making with speediness and correctness.

In-service Investigation on the Flow Dynamics of a Trayed Column from the Measurement of an Internal Density by using a Gamma Absorption Technique (Gamma Absorption Technique를 이용한 Trayed Column의 가동 중 내부 밀도분포 측정에 의한 유체 유동상태 진단)

  • Kim, Jae-Ho;Kim, Jong-Bum;Kim, Jin-Seop;Lee, Na-Young;Lee, Sung-Sik;Jang, Seok-Joon;Jung, Sung-Hee
    • Journal of Radiation Protection and Research
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    • v.33 no.1
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    • pp.35-40
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    • 2008
  • A distillation tower is one of the important facilities which separates and refines a crude oil stream according to certain boiling points. Its operation efficiency can affect the productivity of a refinery substantially. The objective of this study is to elucidate some operational information on the internal conditions of a distillation tower from a measurement of density profile by using a sealed gamma-ray source and a radiation detector. Gamma radiation counts were measured by a BGO detector positioned diametrically outside the tower-wall, opposite to the gamma source(Co-60) as the detector and the source were lowered concurrently. From the results, structural abnormality of the trays was not found inside the tower. Considering the flow distribution patterns, however, a vapor phase was dominantly formed at the upper part of the tower and a liquid phase at the lower part. From the gamma scanning of the distillation tower, it is anticipated that the gamma absorption technique can be used as an important tool for confirming the structural soundness of trays and investigating flow distribution in refinery facilities.

Fish Distribution Characteristics of Mudeungsan National Park (무등산국립공원의 어류 분포 특성)

  • Ko, Myeong-Hun;Jang, Su-Lim;Won, Yong-Jin
    • Korean Journal of Environment and Ecology
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    • v.32 no.2
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    • pp.154-164
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    • 2018
  • We investigated the ichthyofauna and fish community structure of the Mudeungsan National Park, Korea from 2014 to 2016 to prepare a conservation plan. We collected 21 species of 6 families collected from 8 survey stations through skimming nets and cast nets during the period. The dominant and subdominant species were Zacco temminckii (43.0%) and Rhynchocypris oxycephalus (15.1%), respectively. The other abundant species were Z. platypus (11.2%), Pungtungia herzi (10.1%), Squalidus gracilis majimae (8.9%), and Z. koreanus (4.5%). Among the fish collection, 13 species (61.9%) were Korean endemic species, but, endangered species and exotic species were not found. Similarity indices based on species composition and abundance showed the clear division of the fish community into two river systems (Yongsan River drainage system (St. 1-7) and Seomjin River drainage system (St. 8)). The Youngsan River system was further divided into the uppermost (St. 1, 2, 4, 6, and 7) and the upper-middle (St. 3 and 5) regions. The number of species appearing in a year was similar at 19 to 20 throughout the survey period. However, the individual number of fish in 2015 (2,670) was 20% less than that of 2014 (3,366) and 2016 (3,429), respectively. The probable reason for this decline is the rapid decline of stream level in 2015 compared to the other years. During the survey period, river works were undergoing at 3 out of 8 stations, having created disturbance in fish habitat and especially impacted on benthic fishes.

Social network analysis for a soccer game (사회네트워크분석을 통한 축구경기 분석)

  • Choi, Seung-Bae;Kang, Chang-Wan;Choi, Hyong-Jun;Kang, Byung-Yuk
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.6
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    • pp.1053-1063
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    • 2011
  • Social network analysis is the social statistical analysis of any social structure involving a stream of mutual information between observations. In this study we used the results of passes between players in a soccer game. The analysis contents are as follows. (1) Players with important or leading roles are identified. (2) Players are assessed by pass frequency and the success rate of passes. The purpose of this study is for use as basic data for future team strategy, and achieves this by evaluating the role of each individual player within a team. In this study, social network analysis without separating positions is conducted, and is also performed for defensive and attacking positions respectively. The results of this study are as follows: First, when complete team data were available, the players performing leadership roles were Jung-woo Kim, Sung-yeung Ki and Chung-young Lee, whereas Jeong-su Lee acted as a sub-leader. In case of data for defensive positions Jeong-su Lee was a leading player, and in terms of attacking positions, all of the players excelled in the game and could be evaluated as playing lead roles.

Network-adaptive H.264 Video Streaming over IEEE 802.11e (IEEE 802.11e에서 네트워크 적응적인 H.264 비디오 스트리밍)

  • Lee, Sun-Hun;Chung, Kwang-Sue
    • Journal of Broadcast Engineering
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    • v.13 no.1
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    • pp.6-16
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    • 2008
  • An instable wireless channel condition causes more packet losses and retransmissions due to interference, fading, station mobility, and so on. Therefore video streaming service over a wireless networks is a challenging task because of the changes in the wireless channel conditions and time-constraints characteristics of the video streaming services. To provide efficient video streaming over a wireless networks, QoS-enhanced MAC protocol, IEEE 802.11e, is standardized recently. Tn this paper, we propose a new network-adaptive H.264 video streaming mechanism in the IEEE 802.11e wireless networks. To improve the quality of video streaming services, video stream has to adapt to the changes in the wireless channel conditions. The wireless channel conditions are estimated by the packet loss probability and informed to the application layer by the cross-layering. According to the wireless channel information, the video streaming application filters out the low-priority data. This adaptation mechanism efficiently uses system resources because it drops the low-priority data in advance. Therefore, our cross-layer design can provide improved video streaming services to the end-user. Through the implementation and performance evaluation, we prove that the proposed mechanism improves the QoS of the video streaming by providing the smoothed playback.

Study about the formation of doctors' identity in the Joseon(朝鮮) Dynasty (조선시대(朝鮮時代) 의원(醫員)의 변화와 자기의식(自己意識) 형성)

  • Kim, Seong-Su
    • Korean Journal of Oriental Medicine
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    • v.17 no.2
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    • pp.1-15
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    • 2011
  • In the latter half of the Joseon(朝鮮) Dynasty, the medical world was encountering a great change. It is said that a large stream between the first half and the latter half of the Joseon Dynasty was a qualitative transition from official relationships to private relationships, that is, from adjustments by governmental power to contractual relationships between individuals. Doctors who can be said to be the core of the medical world became to be left in severer competition. The fact that the number of people engaged in medical practice increased to the extent that doctors had to compete with each other implies that not only demand for medical care was increasing but also that medical care was becoming social service that must be shared by all people in the Joseon Dynasty rather than by small numbers of men of power. Anyway, it seems like that, in the competition that was becoming fiercer, they tried to establish their authority in diverse methods unlike before. As an authority to determine the social positions of doctors in the latter half of the Joseon Dynasty, the government was still occupying an important position, but doctors tried to show off their medical techniques utilizing excellent teachers or books. Meanwhile, they were making efforts to improve treating skills and thereby they were contributing to the development of medical techniques although they were sometimes criticised because of radical treatment or fierce drugs. In this process, it seems like that some doctors made efforts to establish the social meaning of medicine and their identity. In the short dialogue with Hong Yangho(洪良浩), Cho Gwangil(趙光一) was presenting the image of doctors as active and subjective beings. Pointing out the fact that in the society where feudal position systems were still impregnable, even the Confucian scholars who could be considered as a leading group could not but be passive in front of the sovereign power, he emphasized the fact that doctors could practice treatment as they liked. In that he re-discovered the meaning of treating people's diseases as a professional intellectual and that he was forming a subjective sense that medical techniques are active self expression, it can be carefully said that Cho Gwangil was obtaining his identity as a doctor. In the society in the Joseon Dynasty where the position systems were still valid and the value system under Neo-confucianism(性理學) supporting the system was impregnable, this change can be thought to be small yet quite meaningful.

Design and Implementation of Media Manager in Multimedia Streaming Framework (스트리밍 프레임워크에서 미디어 관리자의 설계 및 구현)

  • Lee, Jae-Wook;Lee, Sung-Young;Hong, Een-Kee
    • Journal of KIISE:Computing Practices and Letters
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    • v.7 no.4
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    • pp.273-287
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    • 2001
  • In this paper, we introduce our experience for designing and implementing a media manager in the Integrated Streaming Service Architecture (ISSA) developed by the authors. The media manager is regarded as a necessary module in the ISSA framework for the following reasons. It realizes that from which locations of the media source devices, the media streams are coming. Once it knows where the origin is, the media manager should recognizes what types of stream are. After that, it performs how to chose an appropriate CODEC to handle the recognized input streams efficiently, and what type of media playback device should be selected. In order to do such a job efficiently, the proposed media manager consists of two modules source module and sink module. The major role of a media source module is to make an abstraction for the media streams that are coming from various types of media device. This, in consequence, enables a media manager to consistently handle tlle media streams without considering wherever they come from. On the other hand, the media sink module distributes the input streams to an appropriate media device to playback. One of the remarkable virtues of the proposed media manager is an ability to supporting high value-added database services since it provides an interface between the ISSA and real-time multimedia database. Also, it provides the RTP!RTSP source filter and Winamp gateway modules which allow the flexibility to the system. Moreover, the media manager can adopt any types of new media which in fact will provide scalability to the ISSA.

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