• Title/Summary/Keyword: Main stream

Search Result 1,061, Processing Time 0.03 seconds

Development of Strategies to Improve Water Quality of the Yeongsan River in Connection with Adaptation to Climate Change (기후변화의 적응과 연계한 영산강 수질개선대책 개발)

  • Yong Woon Lee;Won Mo Yang;Gwang Duck Song;Yong Uk Ryu;Hak Young Lee
    • Korean Journal of Ecology and Environment
    • /
    • v.56 no.3
    • /
    • pp.187-195
    • /
    • 2023
  • Almost all of the water from agricultural dams located to the upper of the Yeongsan river is supplied as irrigation water for farmland and thus is not discharged to the main stream of the river. Also, most of the irrigation water does not return to the river after use, adding to the lack of flow in the main stream. As a result, the water quality and aquatic health of the river have become the poorest among the four major rivers in Korea. Therefore, in this study, several strategies for water quality improvement of the river were developed considering pollution reduction and flow rate increase, and their effect analysis was performed using a water quality model. The results of this study showed that the target water quality of the Yeongsan river could be achieved if flow increase strategies (FISs) are intensively pursued in parallel with pollution reduction. The reason is because the water quality of the river has been steadily improved through pollution reduction but this method is now nearing the limit. In addition, rainfall-related FISs such as dam construction and water distribution adjustment may be less effective or lost if a megadrought continues due to climate change and then rainfall does not occur for a long time. Therefore, in the future, if the application conditions for the FISs are similar, the seawater desalination facility, which is independent of rainfall, should be considered as the priority installation target among the FISs. The reason is that seawater desalination facilities can replace the water supply function of dams, which are difficult to newly build in Korea, and can be useful as a climate change adaptation facility by preventing water-related disasters in the event of a long-term megadrought.

On the Determination of Slope Stability to Landslide by Quantification(II) (수량화(數量化)(II)에 의한 산사태사면(山沙汰斜面)의 위험도(危險度) 판별(判別))

  • Kang, Wee Pyeong;Murai, Hiroshi;Omura, Hiroshi;Ma, Ho Seop
    • Journal of Korean Society of Forest Science
    • /
    • v.75 no.1
    • /
    • pp.32-37
    • /
    • 1986
  • In order to get the fundamental information that could be useful to judge the potentiality of occurrence of rapid shallow landslide in the objective slope, factors selected on Jinhae regions in Korea, where many landslides were caused by heavy rainfall of daily 465 mm and hourly 52mm in August 1979, was carried out through the multiple statistics of quantification method (II) by the electronic computer. The net system with $2{\times}2cm$ unit mesh was overlayed with the contour map of scale 1:5000. 74 meshes of landslides and 119 meshes of non-landslide were sampled out to survey the state of vegetative cover and geomorphological conditions, those were divided into 6 items arid 27 categories. As a result, main factors that would lead to landslide were shown in order of vegetation, slope type, slope position, slope, aspect and numbers of stream. Particularly, coniferous forest of 10 years old, concave slope and foot of mountain were main factors making slope instability. On the contrary, coniferous forest of 20-30 years old, deciduous forest, convex slope and summit contributed to the stable against Landslide. The boundary value between two groups of existence and none of landslides was -0.123, and its prediction was 72%. It was well predicted to divide into two groups of them.

  • PDF

The Bacteriological Survey of the Main Streams in Kyong-Ju City - on Samonellae - (경주시를 관류하는 하천수에 대한 세균학적 조사 - 살모넬라에 대하여 -)

  • Che, Ik-Han
    • Journal of Preventive Medicine and Public Health
    • /
    • v.22 no.2 s.26
    • /
    • pp.268-275
    • /
    • 1989
  • The studies on the standard plate count, most probable number(MPN) and isolation of the Enterobacteriaceae, especially Salmonella species from stream waters of Kyong-Ju city were carried out from June to July, 1988. The relationship between water temperature, weather and standard plate count were observed. The locations where all of the MPN was higher than 1,600 were Mun-chon bridge, Wol-song bridge, Go-hun bridge and the area adjoining the Hyong-san river. The higher the water temperature, the more the viable counts without rain. Bacteriological survey of the Salmonella species was performed with the total 80 specimens isolated from 16 areas which are the main streams in Kyong-Ju city. The author identified S strains(2.36%) of Salmonella typhi, 5 strains(2.3%) of Salmonella paratyphi, 2 strains(1.42%) of Salmonella paratyphi B, 63 strains(29.72%) of other Salmonella groups by biochemical tests and serotyping tests with slide agglutination.

  • PDF

Characteristics of Water Quality at Main Streams and Lake Doam in Daegwallyeong Area (대관령 지역 주요 하천 및 도암호의 수질 특성)

  • Park, Kyeong-Hun;Kim, Byeong-Seok;Yun, Hye-Jeong;Ryu, Kyoung-Yul;Yun, Jeong-Chul;Choi, June-Yeol;Kim, Ki-Deog;Jin, Yong-Ik
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.45 no.6
    • /
    • pp.882-889
    • /
    • 2012
  • This study was surveyed that water physiochemical characteristics and phytoplankton incidence of main stream and Lake Doam near to Daegwallyeong agricultural area. Based on above results, it was conducted to get information overall water characteristics in south Han upstream river. COD value of Lake Doam was $6.1mg\;L^{-1}$ and T-P (Total phosphorous) from there was $0.26mg\;L^{-1}$ which was higher than the value of grade VI based on lake water living environment standard. Suspended solid was an average of 9.77 NTU which was higher than value of lake living standard. Concentration of phytoplankton was over $2.0{\times}10^3Cell\;mL^{-1}$ from July to September. It was considered that cyanobacteria were occurred due to massive influx of nutrient material by high temperature and rainfall during this season. Compare to Ontario's sediment quality guidelines, T-N and T-P was middle value between LEL and SEL in Lake Doam. This value means that contamination in water is serious. Therefore, it is considered that systematic management was needed to reduce and block contamination source.

The Development of Real-time Video Associated Data Service System for T-DMB (T-DMB 실시간 비디오 부가데이터 서비스 시스템 개발)

  • Kim Sang-Hun;Kwak Chun-Sub;Kim Man-Sik
    • Journal of Broadcast Engineering
    • /
    • v.10 no.4 s.29
    • /
    • pp.474-487
    • /
    • 2005
  • T-DMB (Terrestrial-Digital Multimedia Broadcasting) adopted MPEG-4 BIFS (Binary Format for Scene) Core2D scene description profile and graphics profile as the standard of video associated data service. By using BIFS, we can support to overlay objects, i.e. text, stationary image, circle, polygon, etc., on the main display of receiving end according to the properties designated in broadcasting side and to make clickable buttons and website links on desired objects. Therefore, a variety of interactive data services can be served by BIFS. In this paper, we implement real-time video associated data service system far T-DMB. Our developing system places emphasis on real-time data service by user operation and on inter-working and stability with our previously developed video encoder. Our system consists of BIFS Real-time System, Automatic Stream Control System and Receiving Monitoring System. Basic functions of our system are designed to reflect T-DMB programs and characteristics of program production environment as a top priority. Our developed system was used in BIFS trial service via KBS T-DMB, it is supposed to be used in T-DMB main service after improvement process such as intensifying system stability.

A Study on the Recent Trends and Prospects of Maritime Satellite Communication Systems (해사위성통신시스템의 현황과 전망)

  • 조성준
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.2 no.1
    • /
    • pp.20-28
    • /
    • 1977
  • The shipping business which consistutes main stream of foreign trades in the world desires more larger and higher speed ships to convey a large amount of cargo at a time rapidly and safely. They also want to introduce new techniques into transportation system so to meet the rapid growing demand of maritime mobile communications with the improvement of efficiency of radio apparatus and reduction of the hard labors of radio operators mechanization and modernization of radio apparatus is necessary. Now HF band is used mainly for communications between maritime mobile stations and coast stations but the quality of received signal is not so good and the coverage is not sufficient by the condition of propagation of waves. There is also limitation of channel capacity in HF band. So to cope with or improve of these defects and meet the demands of modern maritime communication it is essential to introduce maritime satellite communication system in this field. By using the maritime satellite we can establish high quality communication circuits as maritime Telex, Faximile, high speed data transmission line and can expand coverages. Therefore industrial rationalization of marine transportation is possible with the reduction of painful labors of radio operators by improving safety and promoting of efficiency of movement of ships and freights. Obviously it is prospected that the introduction of maritime satellite communication system will bring a rapid promotion of its usuage in maritime mobile communication field and also anticipated that maritime satellite communication system will be a main current in maritime mobile communication field over the world in the near future with moderated cost of transmission links as in the case of INTELSAT in the past 10 years after its first launching.

  • PDF

A Comparative study on the structure of plan in folk houses of Korea and Japan (韓 . 日 民家의 平面構造 比較硏究)

  • ;Chang, Bo-Woong
    • Journal of the Korean Geographical Society
    • /
    • v.29 no.1
    • /
    • pp.3-15
    • /
    • 1994
  • The purpose of this study is to investigate the origin of traditional folkhouses of Japan in connection with those of Korea. Japanese folkhouses have received much influence from the Korean Peninsular, mainland China, northern Asia and Southeast Asia. The writer believes that the main stream of folkhouse culture origineted in the Korean Peninsular and flowed into the Japanese Islands. There ara many striking similarities in the folkhouses of Korea and Japan. Firstly, double-row room houses are distributed in the northeastern part of the Korean Penininsular and all parts of the Japanese Islands, and they are classified into the five-room type and four-room type. These types are very similar in both nations in the aspects of and floorplan and distributing patterns. Because floorplan may be used as an indicator of culture regions and cultural diffusion both, nations are believed to be closely related in the interchange of cultures in ancient times. Secondly, stables are allocated to the main house, and they are called "magu" in common "Magu" means horse stable, but there are no horses in it. In ancient times, however, many horses were kept in "magu" in both countries. Thirdly, there are much similarities in the function and structure of the folkhouses of both countries. The characteristics of folkhouses of Japan could be explained as the result of cultural diffusion from the Korean Peninsular.on from the Korean Peninsular.

  • PDF

Analysis on Channel Morphology and Rock Resistance by Difference of Bedrock Types between Upper and Lower Reach (상.하류의 기반암 차이에 따른 하천의 형태와 암석의 저항력 분석)

  • Lee, Gwang-Ryul
    • Journal of the Korean Geographical Society
    • /
    • v.42 no.1 s.118
    • /
    • pp.27-40
    • /
    • 2007
  • The streams evolve to diverse forms influenced by various factors such as rock resistance tectonic process, sediments and discharge. This study focuses on erosion resistance of rocks among these factors. The morphology of plane and longitudinal profile has been analysed in upper and lower reach of 6 streams using GIS; Yeoryong-cheon, Heungjeong-cheon, Duhak-cheon, Daehwa-cheon, Namcheon-cheon, Guryong-cheon, having distinct bedrock types between upper and lower reach. While the basins of granite have gentle slope, low concavity and wide valley area, those of gneiss form steep slope, high concavity and narrow valley area. However, the basins of sedimentary rock make steep slope and high relief in main channel, the other features show some differences in each stream. Among the various morphological features, the indices on slope and concavity of main channel, drainage density, ratio of valley area, average slope and average relief of the basin which have clear differences between rocks in upper and lower reach are calculated to interpret the erosion resistance of rocks in upper and lower reach. As a result, the upper reaches composed of gneiss have the highest erosion resistance, sedimentary rocks in upper and lower reaches show moderate resistance, and granite reaches generally have the lowest resistance except the upper reaches bordered by sedimentary rock.

Evaluation of Habitat Improvement Using Two-Dimensional Fish Habitat Modeling after the Connectivity Restoration in an Isolated Former Channel (2차원 어류 서식처 모의를 이용한 격리된 구하도의 연결성 복원에 따른 서식지 개선 평가)

  • Kim, Seog Hyun;Kim, Dana;Cho, Kang-Hyun
    • Ecology and Resilient Infrastructure
    • /
    • v.2 no.2
    • /
    • pp.137-146
    • /
    • 2015
  • Lateral connectivity between a main channel and a former channel plays an integral role in maintaining ecological functions of stream-floodplain ecosystems. This study virtually restored the connectivity of the former channel, which is currently isolated by channelization, in the Mangyeong River, Korea. Fish habitat improvement after the connectivity restoration was evaluated using River2D, two-dimensional depth-averaged hydraulic modeling, depending on normal and flood flow conditions. Target fish species were crucian carp (Carassius auratus), which are known as lentic species, and pale chub (Zacco platypus), known as lotic species. The weighted usable area (WUA) of the two species was increased after the connectivity restoration: the two-way connection between the main and formal channels was more effective than the one-way connection. The result of the physical habitat simulation at a flood flow condition demonstrated an increased rate of the WUA than during a normal flow condition. In particular, the WUA of pale chub increased about four times on the two-way connectivity restoration. This result suggests that habitat availability of both lentic and lotic fish species will increase after a connectivity restoration, and a two-way connectivity restoration may be more effective. In addition, the restored formal channel would function as a shelter for fish during the flood season.

Perceptions of Disabled Sports in Newspapers Using Semantic Networks Analysis (신문기사에 나타난 장애인스포츠에 대한 인식 -의미연결망을 활용한 빅데이터 분석-)

  • Han, Min-kyu;Kim, Won-Kyoung;Yoon, Jiwun
    • 재활복지
    • /
    • v.20 no.4
    • /
    • pp.157-175
    • /
    • 2016
  • The purpose of this study was to analyze the perceptions of disabled sports that were reported the newspapers using semantic network analysis method. for this purpose, 745 news articles were selected from 21 source in Naver news searching engine. The main keyword for searching on newspapers was 'disabled sports'. Krkwic software was used for keyword cleansing and co-occurrence of text to text matrix in frequencies. Centrality indices that are degree, between and eigenvector, were used to analyze the perceptions of disabled sports from Netminer 4.0 for semantic network analysis. The conclusion of overall results from this study are follows; First, the core keyword of disabled sports in newspapers are 'impression', 'challenge', 'festival', 'dream' and hope. And there is different concepts of cognition among types of disability. Second, there are two elements on the perceptions of disabled sports from reported newspapers; sports performance and emotional. Specifically, main stream of keyword were 'Paralympics' and 'Special Olympics' on sports performance element and 'impressive' and 'challenge' in emotion element.