• Title/Summary/Keyword: Site effect

Search Result 3,700, Processing Time 0.027 seconds

Drainage system for leakage treatment of cement concrete structure in underground (콘크리트 지하구조물 누수 처리를 위한 유도배수시스템)

  • Kim, Dong-Gyou
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.21 no.4
    • /
    • pp.573-585
    • /
    • 2019
  • The objective of this study is to propose the drainage system that has been improved the workability, waterproofing and drainage performance to treat the leakage from the cement concrete structures in underground. It is improved that the pipe for conveying ground leak in the existing drainage system had the problem in workability and waterproof. The drainage systems with the improved pipe for conveying ground leak were constructed in conventional concrete lining tunnels to evaluate the workability, waterproofing and drainage. The waterproof and the drainage performance of the drainage system was evaluated by injecting 1,000 ml of red water in the back of the drainage system at 3 weeks, 6 weeks, 9 weeks, 11 weeks, 14 weeks, 17 weeks and 23 weeks. During 6 months of field performance test, the average daily temperature of the tunnel site was measured from $-12.4^{\circ}C$ to $19.7^{\circ}C$. The daily minimum temperature was $-17.2^{\circ}C$ and the daily maximum temperature was $26.7^{\circ}C$. There was no problem in waterproof and drainage performance on the pipe for conveying ground leak and the drainage system during 6 months for field performance test. It is concluded that the improved drainage system can be applied to various cement concrete underground structures where leakage occurs, and has little seasonal effect.

A Nonparametric Long-Term Trend Analysis Using Water Quality Monitoring Data in Nam-River (남강 수질측정망 자료를 이용한 비모수적 장기 수질 추세 분석)

  • Jung, Kang-Young;Kim, Myojeong;Song, Kwang Duck;Seo, Kwon Ok;Hong, Seong Jo;Cho, Sohyun;Lee, Yeong Jae;Kim, Kyunghyun
    • Journal of Environmental Science International
    • /
    • v.27 no.11
    • /
    • pp.1029-1048
    • /
    • 2018
  • In this study, seasonal Mann - Kendall test method was applied to 12 stations of the water quality measurement network of Nam-River based on data of BOD, COD, TN and TP for 11 years from January 2005 to December 2015 The changes of water quality at each station were examined through linear trends and the tendency of water quality change during the study period was analyzed by applying the locally weighted scatter plot smoother (LOWESS) method. In addition, spatial trends of the whole Nam-River were examined by items. The flow-adjusted seasonal Kendall test was performed to remove the flow at the water quality measurement station. As a result, BOD, COD concentration showed "no trand" and TN and TP concentration showed "down trand" in regional Kendall test throughout the study period. BOD and TP concentration in "no trand", COD, and TN concentration showed an "up trand" tendency in Nam-River dam. LOWESS analysis showed no significant water quality change in most of the analysis items and stations, but water quality fluctuation characteristics were shown at some stations such as NR1 (Kyungho-River 1), NR2 (Kyungho-River 2), NR3 (Nam-River), NR6 (Nam-River 2A). In addition, the flow-adjusted seasonal Kendall results showed that the BOD concentration was "up trand" due to the flow at the NR3 (Nam-River) station. The COD concentration was "up trand" due to the flow at NR1 (Kyungho-River 1) and NR2 (Kyungho-River 2) located upstream of the Nam-River. The effect of influent flow on water quality varies according to each site and analysis item. Therefore, for the effective water quality management in the Nam-River, it is necessary to take measures to improve the water quality at the point where the water quality is continuously "up trand" during the study period.

Screening Assessment of Radiological Effect From Clearance of Decommissioning Concrete Waste Based Upon Recycling Framework of Construction Waste in Korea (국내 건설폐기물 재활용 체계를 반영한 해체 콘크리트 폐기물 자체처분 방사선 영향 예비평가)

  • Lim, Kun-Su;Cheong, Jae Hak;Whang, Joo Ho
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.16 no.4
    • /
    • pp.441-454
    • /
    • 2018
  • Since the permanent shutdown of Kori Unit 1 in 2017, a full-scale decommissioning project for a commercial nuclear reactor has been approaching. It is estimated that about 160,000 t of low-activity concrete waste will be produced from decommissioning of one unit of this commercial nuclear power reactor. Accordingly, it is necessary to review whether the effectiveness of the current regulatory framework for clearance waste (i.e. waste stream that meets activity concentration guidelines or dose criteria for clearance set forth in NSSC Notice No. 2017-65) can be maintained for the clearance of a bulk amount of concrete waste. In this regard, the IAEA SRS No. 44, which was used as a basis for revision of the Korean clearance regulations, is thoroughly analyzed and the radiological effects from four different clearance scenarios, along with input values and parameters derived from industrial practices in Korea, were evaluated. Though it is shown that the maximum annual dose from most recycling scenarios will be less than the clearance dose criterion for the normal scenario (i.e. an order of magnitude of $0.01mSv{\cdot}y^{-1}$), the radiation dose, estimated with conservative assumptions for the banking scenario, may exceed the above clearance dose criteria. Therefore, for safe and sustainable clearance of the bulk amount of concrete waste, it is required to diversify the concrete waste processors, perform more detailed site-specific assessment, and apply limiting conditions to the banking scenario.

A Preliminary Study on the Evaluation of Internal Exposure Effect by Radioactive Aerosol Generated During Decommissioning of NPPs by Using BiDAS (BiDAS를 적용한 원전 해체 공정 시 발생되는 방사성 에어로졸의 내부피폭 영향평가 사전 연구)

  • Song, Jong Soon;Lee, Hak Yun;Kim, Sun Il
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.16 no.4
    • /
    • pp.473-478
    • /
    • 2018
  • Radioactive aerosol generated in cutting and melting work during the NPP decommissioning process can cause internal exposure to body through workers' breath. Thus, it is necessary to assess worker internal exposure due to the radioactive aerosol during decommissioning. The actually measured value of the working environment is needed for accurate assessment of internal exposure, but if it is difficult to actually measure that value, the internal exposure dose can be estimated through recommended values such as the fraction of amount of intake and the size of particles suggested by the International Committee on Radiological Protection (ICRP). As for the selection of particle size, this study applied a value of $5{\mu}m$, which is the size of particles considering the worker recommended by the ICRP. As for the amount of generation, the amount of intake was estimated using data on the mass of aerosol generated in a melting facility at a site in Kozloduy, Bulgaria. In addition, using these data, this study calculated the level of radioactivity in the worker's body and stool and conducted an assessment of internal exposure using the BiDAS computer code. The internal exposure dose of Type M was 0.0341 mSv, that of Type S was 0.0909 mSv. The two types of absorption showed levels that were 0.17% and 0.45% of the domestic annual dose limit, respectively.

Process of change and cause of the perform a play on the stage of the Duhak nongak(農樂) in Jecheon (제천시 두학동 상풍마을 농악(農樂)의 변천 과정과 연희화(演戱化))

  • Choi, Ja-Un
    • (The) Research of the performance art and culture
    • /
    • no.32
    • /
    • pp.371-397
    • /
    • 2016
  • The function of the Duhak nongak(農樂) in Jecheon consist of Ceremony, Labor, and Entertainment. Before the commemorative rites for village god village people beat a small gong. This is a evidence of the drive away evil spirits in New Year's Eve of the lunar year. Before harden house site village peoples beat musical instrument noisily. In order to press hard the god of the earth they play musical instrument. Musical instrument not a simple musical instrument, but a purify and wish tool. When weeding a rice paddy Durae organized in Sangpung village. Durae are less effective than communal sharing of labor in weeding effect. Nonetheless, Nongak carried out core function in Durae. In order to participate Nonngak concours, peoples made a Pangut. From independence to 1970s people combine traditional nongak and Pangut. Since then village people played Pangut. From 1990s Pangut was played by Duhak Nonngak Preservation Association. Through the participation Nonngak concours, Duhak nongak was regrouped. Finally this nongak prepared Taeguk-jin, Snail-jin, Cross-jin, Sabang-jin, Sanggyeonrae Bans anggyeonrae-jin, Palbang-jin, Rope making and individual play. Duhak Nonngak promptly met the needs of the times. So, they could play Pangut. The feature of the Duhak Nonngak is that active cognition, highly skilled musician a patron and scouting a competent leader.

Development of Incident Detection Algorithm Using Naive Bayes Classification (나이브 베이즈 분류기를 이용한 돌발상황 검지 알고리즘 개발)

  • Kang, Sunggwan;Kwon, Bongkyung;Kwon, Cheolwoo;Park, Sangmin;Yun, Ilsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.17 no.6
    • /
    • pp.25-39
    • /
    • 2018
  • The purpose of this study is to develop an efficient incident detection algorithm by applying machine learning, which is being widely used in the transport sector. As a first step, network of the target site was constructed with micro-simulation model. Secondly, data has been collected under various incident scenarios produced with combination of variables that are expected to affect the incident situation. And, detection results from both McMaster algorithm, a well known incident detection algorithm, and the Naive Bayes algorithm, developed in this study, were compared. As a result of comparison, Naive Bayes algorithm showed less negative effect and better detect rate (DR) than the McMaster algorithm. However, as DR increases, so did false alarm rate (FAR). Also, while McMaster algorithm detected in four cycles, Naive Bayes algorithm determine the situation with just one cycle, which increases DR but also seems to have increased FAR. Consequently it has been identified that the Naive Bayes algorithm has a great potential in traffic incident detection.

Theatre of Imagination: Study on New Languages in the Theatre Experiment of Ara Kim (상상력의 연극 이미지의 무대구성작업에 관하여 김아라 연출작업에 나타난 새로운 무대언어)

  • Nam, Sangsik
    • Journal of Korean Theatre Studies Association
    • /
    • no.48
    • /
    • pp.261-288
    • /
    • 2012
  • This paper attempts to research on the new language in the directing of Ara Kim. She was cranky on working on the stage to experiment with her own style since the 1980s and so opened a new dawn in modern Korean theatre. She leaded the Korean experimental theatre. The background of this experiment is her idea on theatre. And here, we have to look the subject that she setted for the work in Chuksan: Ritual Past, Ritual Present. To her, the theatre has the function of ritual and fest. The theatre suggests universal tragedy given to human as natural life force and has its own agenda to drive people to healing. For it, Ara Kim explores archetypal forms and languages before the fragmentation of genres of art. Her theatre shows the results of experiments in which such languages are recreated with modernized sensibilities. We here, for example by outdoor performance in Chuksan Human Lear, try to interpret the aesthetic principles that body out her ritual theatre. And what we looked at though, is the base of the 'complex-genre-music-theatre', the methode to 'compose' the stage elements and put it all together. The directing of Ara Kim has, in terms of the composition of the stage elements, much of the indisputable artistic value. Her theatre is, so to speak, theatre of image, and it is theatre of imagination that completed by the audience's imagination. Human Lear which has its own characteristic in image fragments, convert the original Lear into a simple tale. It serves as background of the modern ritual that shows the most basic human instincts. We meet in Human Lear a ritual tale with some list of image for the human instincts. The arrangement of image, the montage of scene shows the performance as a kind of artistic space. In Human Lear the space is the natural one. It centers around the arena stage. The objects installed in the space changes it into the laboratory for 'seeing' the happening. The spectators see the performance and at the same time see themselves in the nature laboratory. They see, and equally, they are visible objects. They see the performance and us in the space in which the performance takes place. That is what Ara Kim with her modern ritual really aims. That aim is to this days still in effect. It is a major driver of her experiments to extend the boundary of the theatre. The ritualistic site-specific performance in Akor Wat, Cambodia, A Song of Mandala is the latest great product from her experiments. On the other hand, she continues on her way to experiment with pure stage elements. The 'Station' series(Station of Water, The Station of Sand, The Station of Wind) she recently showed are the non-verbal performance with all the stage elements: movement, sound, body, light, colour, objects and so on.

Assessment of Water Quality in the Miho Stream Using Multivariate Statistics (다변량 통계기법을 이용한 미호천 본류 수질특성 평가)

  • Yoon, Hyeyoung;Kim, Jeehyun;Chae, Minhee;Cho, Yoonhae;Cheon, Seuk
    • Journal of Environmental Impact Assessment
    • /
    • v.28 no.4
    • /
    • pp.373-386
    • /
    • 2019
  • In The study, is to investigate the spatial characteristics of the Miho stream, which is the main tributary of the Geum River system, and to identify the main factors influencing the water quality using water quality analysis and multivariate analysis. The survey subjects were selected as 7 main sites in the Miho stream water system, From 2012 to 2017, 16 items including weather temperature and weather data were used for multivariate analysis. As a result of the water quality analysis, the average concentration of BOD and COD for 6 years was 3grade (normal) compared with the water quality environmental standard (river) of conditions. The concentrations of nitrogen and phosphorus were highest at th upstream site, then decreased and then increased again by the hydrogeological and geomorphological effect. Cluster analysis of spatial and water quality characteristics, it was evaluated as three clusters and the pollution sources is the greatest impact. As a result of principal component analysis and factor analysis on each cluster and mainstream, three to four major components were extracted. Main stream and the Cluster 1, Cluster 3 first principal factor included nitrogen and seasonal factors,first factor of Cluster 2 included nitrogen and water temperature. Nitrogen is the principal factor which affects water quality in Miho stream.

Research on the ancient iron technology of Jungwon, the center of iron industry (제철산업의 중심 중원에서 고대 제철기술을 탐구하다)

  • Do, Eui Chul;Lee, Eun Woo;Seok, Je Seop;Jang, Min Seong
    • Korean Journal of Heritage: History & Science
    • /
    • v.48 no.1
    • /
    • pp.148-165
    • /
    • 2015
  • Iron was one of the most influential factors for formation and development of ancient countries. The diffusion of ironware had increased agricultural productivity and brought about military technical revolution. Needless to say, the rise and fall of the countries depended on the possession of stable iron production. Raw materials and fuels are the key factors for mass production of iron and a transportation route is essential to supply the goods. Jungwon area satisfies the three factors. There are many iron manufacture sites such as Jincheon Seokjang-ri Gusan-ri, and Chunju Chilgeum-dong Tangeumdae earthen ramparts in the Jungwon area. In order to study the ancient iron manufacture technique, reconstitution experiment was carried out using restored furnace which was made based on the Jincheon Seokjang-ri B-23 furnace. Some notable results were identified with the experiment as in the followings. Firstly, a roasting process has a connection with the decrease of hardness of the iron ore. Secondly, melting of the blast pipe as well as the formation of product within the furnace had a crucial effect on the cessation of the experiment. Thirdly, reduced iron in various locations within the furnace prove that there was enough reducing environment during the working. Not only melting point but also properties of iron can vary depending on the carbon contents. For the reason, formation of approximate environment in which iron can react to the chalcoal is the most important factor in terms of iron manufacture.

A study on evaluation of flexural toughness of synthetic fiber reinforced shotcrete (구조용 합성섬유 보강 숏크리트 휨인성 평가에 관한 연구)

  • Moon, Kyoung-Sun;Kim, Seog-Jin;Kim, Yeon-Deok;Min, Byeong-Heon;Kim, Sang-Hwan
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.21 no.3
    • /
    • pp.433-452
    • /
    • 2019
  • This study deals with shotcrete reinforcing performance according to the amount of synthetic fiber (PP fiber) and proper evaluation method. The shotcrete compressive strength, flexural strength and flexural toughness were tested by setting the mixing amounts of steel fiber ($37.0kg/m^3$) and synthetic fiber (PP fiber) as parameters ($5.0kg/m^3$, $7.0kg/m^3$ and $9.0kg/m^3$). Particularly, circular panel flexural toughness test (Road and Traffic Authority, RTA) was performed to evaluate the shotcrete energy absorption capacity. As a result, the compressive strength and the bending strength of the steel fiber reinforced shotcrete were large, but the flexural toughness of the synthetic fibe (PP fiber) reinforced shotcrete was large. Therefore, synthetic fiber (PP fiber) reinforced shotcrete is considered to have a reinforcing effect comparable to that of steel fiber reinforced shotcrete. Analysis of the relationship between the flexural toughness and the energy absorption capacity of synthetic fiber (PP fiber) reinforced shotcrete revealed that the energy absorbing ability is exhibited at a flexural toughness lower than the allowable standard (3.0 MPa). (Class A: 2.55 MPa = 202J, Class B: 2.72 MPa = 282J, Class C: 3.07 MPa = 403J). As a result of this study, it can be concluded that the actual shotcrete support performance can be evaluated by evaluating the support performance of the shotcrete measured at less than the allowable standard (3.0 MPa) at the actual tunnel site.