• Title/Summary/Keyword: bank safety

Search Result 173, Processing Time 0.022 seconds

Slope Stability Analysis of New Gabion Wall System with Vegetation Base Materials for Stream Bank Stability and Rehabilitation (계안 복원을 위한 식생기반재 돌망태 옹벽의 계안 안정효과 분석)

  • Choi, Hyung Tae;Jeong, Yong-Ho;Park, Jae-Hyeon
    • Journal of Korean Society of Forest Science
    • /
    • v.101 no.1
    • /
    • pp.130-137
    • /
    • 2012
  • This study has conducted to develop new gabion wall systems with vegetation base materials for stream bank stability and rapid rehabilitation. Vegetation base materials are primarily compounded with fine soil, organic composts and peat moss as plant fibers, a water retainer and a soil improver. Normally gabion wall systems resist the lateral earth pressures or stream power by their own weight. Therefore, fill material must have suitable weight, compressive strength and durability to resist the loading, as well as the effects of water and weathering. In this project, 100 to 200-mm clean, hard stones are basically specified, and about 50-mm rubbles are also used. Test application of new gabion wall system carried out in the stream bank of a small stream in the Gwangreung experimental forest, belonging to Korea Forest Research Institute (KFRI) in December 16th, 2006. As a result of the analysis of hydraulic stability of new gabion wall system, gabion wall system has highest threshold shear stress when the gabion wall covered by vegetation. New gabion wall system is highly resistant to sliding and overturning because safety coefficients exceed 1.5. As a result of term of slope stability analysis of new gabion wall system by Bishop and Fellenius methods, stability of stream bank was highly increased after the construction of gabion wall. Therefore, new gabion wall system is effective to stabilize unstable stream bank.

Numerical Simulation for River Safety of Saemangeum Basin according to Master Plan (새만금 종합개발계획에 따른 새만금 유역 치수 안전성 수치모의)

  • Jeong, Seok il;Yoo, Hyung Ju;Ryu, Kwang Hyun;Lee, Seung Oh
    • Journal of the Korean Society of Safety
    • /
    • v.33 no.5
    • /
    • pp.127-133
    • /
    • 2018
  • The Saemangeum master plan includes dredging and waterproofing materials, construction projects that can change the hydraulic characteristics of the Saemangeum and Mangyeong and Dongjin River basins. In this study, the river safety of 2030 when the Saemangeum master plan was completed for 100 year frequency, 500 year frequency and 100 year frequency applied RCP 8.5 scenario was examined using Delft3D. As a result of the analysis, it was confirmed that there was no overflowing point at the 100 year frequency, but the difference between the flood level and the river bank elevation was relatively small at the curved and river joint part. At the 100-year frequency with the 500-year frequency and the RCP 8.5 scenario, the possibility of overflowing at several locations was confirmed. The possibility of river bed loss due to fast velocity appears in the upstream part of Mankyung River and it is necessary to monitor the safety of hydraulic structures continuously. In addition, it is expected that the expansion of the area showing the characteristics of the lake due to dredging will affect the sediment mechanism and water quality, so detailed and diverse studies will be needed.

Neutronic analysis of control rod effect on safety parameters in Tehran Research Reactor

  • Torabi, Mina;Lashkari, A.;Masoudi, Seyed Farhad;Bagheri, Somayeh
    • Nuclear Engineering and Technology
    • /
    • v.50 no.7
    • /
    • pp.1017-1023
    • /
    • 2018
  • The measurement and calculation of neutronic parameters in nuclear research reactors has an important influence on control and safety of the nuclear reactor. The power peaking factors, reactivity coefficients and kinetic parameters are the most important neutronic parameter for determining the state of the reactor. The position of the control shim safety rods in the core configuration affects these parameters. The main purpose of this work is to use the MTR_PC package to evaluate the effect of the partially insertion of the control rod on the neutronic parameters at the operating core of the Tehran Research Reactor. The simulation results show that by increasing the insertion of control rods (bank) in the core, the absolute values of power peaking factor, reactivity coefficients and effective delayed neutron fraction increased and only prompt neutron life time decreased. In addition, the results show that the changes of moderator temperature coefficients value versus the control rods positions are very significant. The average value of moderator temperature coefficients increase about 98% in the range of 0-70% insertion of control rods.

Genetic Identification of Spirometra decipiens Plerocercoids in Terrestrial Snakes from Korea and China

  • Jeon, Hyeong-Kyu;Park, Hansol;Lee, Dongmin;Choe, Seongjun;Kim, Kyu-Heon;Sohn, Woon-Mok;Eom, Keeseon S.
    • Parasites, Hosts and Diseases
    • /
    • v.54 no.2
    • /
    • pp.181-185
    • /
    • 2016
  • Human sparganosis is a zoonotic disease caused by infection with larval forms (procercoid/plerocercoid) of Spirometra spp. The purpose of this study was to identify Spirometra spp. of infected snakes using a multiplex PCR assay and phylogenetic analysis of mitochondrial DNA sequence data from the spargana of terrestrial snakes obtained from Korea and China. A total of 283 snakes were obtained that included 4 species of Colubridae comprising Rhabdophis tigrinus tigrinus (n=150), Dinodon rufozonatum rufozonatum (n=64), Elaphe davidi (n=2), and Elaphe schrenkii (n=7), and 1 species of Viperidae, Agkistrodon saxatilis (n=60). The snakes were collected from the provinces of Chungbuk, Chungnam, and Gyeongbuk in Korea (n=161), and from China (n=122). The overall infection rate with spargana was 83% (235/283). The highest was recorded for D. rufozonatum rufozonatum (100%), followed by A. saxatilis (85%) and R. tigrinus tigrinus (80%), with a negative result for E. davidi (0%) and E. schrenkii (0%). The sequence identities between the spargana from snakes (n=50) and Spirometra erinaceieuropaei (KJ599680) or S. decipiens (KJ599679) control specimens were 90.8% and 99.2%, respectively. Pairwise genetic distances between spargana (n=50) and S. decipiens ranged from 0.0080 to 0.0107, while those between spargana and S. erinaceieuropaei ranged from 0.1070 to 0.1096. In this study, all of the 904 spargana analyzed were identified as S. decipiens either by a multiplex PCR assay (n=854) or mitochondrial cox1 sequence analysis (n=50).

Landslide Analysis of River Bank Affected by Water Level Fluctuation I (저수위 변동에 영향을 받는 강기슭의 산사태 해석 I)

  • Kim, You-Seong;Wang, Yu-Mei
    • Journal of the Korean Geosynthetics Society
    • /
    • v.9 no.3
    • /
    • pp.77-85
    • /
    • 2010
  • The change of water level in reservoirs is an important factor causing failure of bank slopes, i.e. landslide. The water level of Three Gorges reservoir in China fluctuate between 145 m and 175 m, as a matter of flood control. During its normal operational state, the rate of water level fluctuation is supposed to range from 0.67 m/d to 3.0 m/d. Majiagou slope is located on the left bank of Zhaxi River, 2.1 km up from the outlet. Zhaxi River is a tributary of the Yangtze River within the Three Gorges area, of which the water level changes with the reservoir. At the back of Majiagou slope, a 20 m long and 3~10 cm wide fissure developed just after the reservoir water level rose from 95 m to 135 m in 2003. This big fissure was a full suggestion of potential failure of this slope. In this study, unsaturated-saturated seepage analyses were carried out to simulate the change of pore-water pressures in the bank slope subjected to the reservoir water level change. The obtained pore-water pressures were then used to evaluate the change in factor of safety (FS) with reservoir water level. It was found that the phreatic line showed a delayed response with respect to the change of the reservoir water level, because the seepage through soil layer was generally slower than water flows itself. During the rising and drawdown process, the phreatic lines take the shapes of concave and convex, respectively. And the fluctuation of reservoir water level just affected the front part of the bank slope, but had little influence on the back of the slope.

  • PDF

Genetic origin identification of Siberian chipmunks (Tamias sibiricus) in pet shops of South Korea

  • Lee, Seo-Jin;Jung, Gil-A;Min, Mi-Sook;Kim, Chuel-Kyu;Lee, Hang;Kim, Chang-Bae;Lee, Mu-Yeong
    • Animal cells and systems
    • /
    • v.15 no.2
    • /
    • pp.161-168
    • /
    • 2011
  • Siberian chipmunks, Tamias sibiricus, are one of several popular companion animals found in the pet shops of South Korea. At present, however, there have been no studies done in South Korea examining their origin even though they could be potential carriers of zoonotic diseases, and are a species of concern for efficient conservation and management strategies. Sequences of the mitochondrial cytochrome b gene (1140 bp) were determined to investigate the origin of Siberian chipmunks sold in four South Korean pet shops through comparison with sequence data from animals of known locality. Nine Siberian chipmunks were collected from pet shops in South Korea, which resulted in nine haplotypes. One (AR) of these coincided with the haplotype previously described. Phylogenetic and network analyses using 53 haplotypes including 45 haplotypes from GenBank showed three phylogenetic groups in South Korea, almost concordant to locality, designated as northern, central, and southern parts as described in a previous study. Of the nine individuals examined from the pet shops, eight were clustered into the northern phylogroup but one (cgrb9153) was grouped with the southern phylogroup, implying that at least the Siberian chipmunks examined in this study did not originate from other countries. It is likely that most individuals sold in the pet shops of Seoul were caught in the wild in Gyeonggi-do and Gangwon-do, or are maternal descendants of captive-bred individuals originating from the northern part of South Korea. It is recommended that conservation and management units of Korean chipmunks should be examined in further detail.

Development of Automatic Crack Detection using the Gabor Filter for Concrete Structures of Railway Tracks (가버 필터를 사용한 철도 콘크리트 궤도 도상의 자동 균열 감지 개발)

  • Na, Yong-Hyoun;Park, Mi-Yun;Park, Ji-Soo;Park, Sung-Baek;Kwon, Se-Gon
    • Journal of the Society of Disaster Information
    • /
    • v.14 no.4
    • /
    • pp.458-465
    • /
    • 2018
  • Purpose: Concrete track that affects on railway safety can detect cracks using image processing technique. However, since a condition of concrete track and surface noisy are obstructed to detect cracks, there is a need for a way to remove them effectively. Method: In this study, we proposed an image processing to detect cracks effectively for Korean railway and verified its performance through experiment. We developed image acquisition system for capture a railway concrete track and acquired railway concrete track images, randomly selected 2000 images and detected cracks in the image process using proposed Gabor Filter Bank methods. Results: As a result, 94% of detection rate are matched to the actual cracks in same quality and format railway concrete track image. Conclution: The crack detection method using Garbor Filter Bank was confirmed to be effective for crack image including noise in the Korean railway concrete track. This system is expected to become an automated maintenance system in the existing human-centered railway industry.

A Study on Severe Accident Management Scheme using LOCA Sequence Database System (원자력발전소의 냉각재상실사고 특성DB를 활용한 중대사고 관리체계연구)

  • Choi, Young;Park, Jong-Ho
    • Journal of the Korean Society of Safety
    • /
    • v.29 no.6
    • /
    • pp.172-178
    • /
    • 2014
  • In terms of an accident management, the cases causing severe core damage need to be analyzed and arranged systematically for an easy access to the results since the Three Mile Island (TMI) accident. The objectives of this paper are to explain how to identify the plant response and cope with its vulnerabilities using the probabilistic safety assessment (PSA) quantified results and severe accident database SARDB(Severe Accident Risk Data Bank) based on sequences analysis results. Although PSA has been performed for the Korean Standard Power Plants (KSNPs), and that it considered the necessary sequences for an assessment of the containment integrity. The developed Database (DB) system includes a graphical display for a plant and equipment status, previous research results by a knowledge-based technique, and the expected plant behaviour. The plant model used in this paper is oriented to the cases of loss of coolant accident (LOCA) is be used as a training simulator for a severe accident management.

A Survey on the Awareness of Human Milk Bank in Korean Female Health Care Providers

  • Hahn, Won-Ho;Song, Joon-Hwan;Park, Suyeon;Kang, Nam Mi;Ahn, Sukhee;Song, Seunghyun
    • Perinatology
    • /
    • v.28 no.1
    • /
    • pp.11-19
    • /
    • 2017
  • Objective: Human milk bank is known as best alternative option for sick infants. However, only two human milk banks (HMBs) are working in Korea. In the present study, we evaluated the awareness on the HMB in female health care provider to find out the issues that would help facilitating HMB establishment in Korea. Methods: The survey questionnaire was developed by a team composed with neonatologists, obstetricians, nurses, nutritionists, and health care specialists. The survey was performed for female health care workers in Soon Chun Hyang Cheonan Hospital between March and June in 2016. Eighty-eight of 110 questionnaires were collected and the results were analyzed. Results: Most of subjects were found to have correct knowledge on the breast milk feeding. However, only 49% of subjects had awareness of the presence of HMB. Unfortunately, less than half of them could get information about HMB by official way including mass media. In addition, 76% of subjects were found not to want to use HMB. Most important reason was found as a concern on the safety of donor milk including life style of donors, infection controls, and possible nutritional loss of banked milk. Conclusion: The purpose and function of HMB was not widely educated and it seems to be one of most important reasons why women have negative concept about HMB in Korea. Thus, further study is warranted with more numbers of subjects after active public education about the HMB.

A Simulation Study on Plant Layout for Increasing Productivity (설비 Layout에 의한 생산성 향상을 위한 시뮬레이션 연구)

  • Lee, Seong-Gyu;Yang, Kwang-Mo;Yun, Jun-Seop;Gang, Gyeong-Sik
    • Proceedings of the Safety Management and Science Conference
    • /
    • 2005.11a
    • /
    • pp.505-510
    • /
    • 2005
  • The manufacturing industries which played a major role in the rapid economic growth and industrialization of Korea in the late 20th century had considerable difficulties changing their manufacturing conditions from producer-oriented conditions to customer-oriented ones according to market changes. In this study, increase plant efficiency because grafts together modular system to plant layout and analyzes Work In Process(WIP) between product's cycle time and each process, family efficient plan wishes to choose opposite bank. Simulation approach used for presented methodology The effect will not gain the results for other reasons the inherent conditions of companies, people, and culture which have been hitherto described, but will be expected to help the direction for a new Lay-out production system to reflect on the native conditions rather than fixed technological means and methods in way of an analysis of fundamental problems which small and medium companies in Korea face.

  • PDF