• Title/Summary/Keyword: Plant Construction site

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The Performance Characteristics of Anti-Surge Devices for High Head Cooling Water Systems in 1,000 MW Thermal Power plants (고수두 1,000 MW 석탄화력발전소 냉각수계통 수격방지장치의 성능특성)

  • Kim, Keun-Pil;Yoo, Hoseon
    • Plant Journal
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    • v.15 no.4
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    • pp.36-42
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    • 2019
  • In recent, according to the tightening of environment regulation policy, the height of the site of the power plant is increased and the length of the cooling water pipe is increased. This has a serious impact on the stability of the plant. This study analyzes the transient phenomenon using LIQT 7.2, an unsteady state one-dimensional analysis software, to secure the stability of 1,000 MW high-capacity coal-fired power plant cooling water system with high head. To prevent water hammer, The effects on performance characteristics were predicted by individual and combination application. The surge pressure of the cooling water which occurs when the pump was stopped without installing the anti-surge devices was the largest at the pump outlet side. The most effective and simple way to reduce surge pressure in these cooling water systems is to combine a vacuum breaker with a hydraulic non-return valve, which is an essential device for pump protection.

Evaluation of Field Applicability of Slope of Improved Soil for Ground Stabilizer (지반안정재 개량토의 토사 비탈면 현장 적용성 평가)

  • Lee, Kang-Il;Park, Seong-Bak;Choi, Min-Ju
    • Journal of the Korean Geosynthetics Society
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    • v.20 no.1
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    • pp.35-44
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    • 2021
  • This research studies the stabilization method for improved soil sloped through the on-site application of Paper Flyash ground stabilizers. The target strength required for improved soil is 500 kPa, and the compressive strength for the slope surface needs to be less than 1,000 kPa after the improvement in order to plant vegetation. To meet this condition, we mixed soil from the site and the ground stabilization material, which is the main material for surface improvement material, performed mixing design and conducted various tests including strength test, permeability test and plantation test. After analyzing the results of the compression test on improved soil slope, we proposed soil constants for the improved soil. In order to evaluate the applicability of the improved soil on the slope, the site construction was carried out on the collapsed slope and the reinforcement evaluation of the surface of the improvement soil was conducted. The stability was not secured before the reinforcement, but the test shows after the reinforcement with improved soil, the safety rate is secured up to 48 hours during the raining period. In addition, the compressive strength of the improved soil at the site was secured at more than 200 kPa adhesion as planned, and the soil hardness test result was also found to be within the specified value of 18-23 mm, which increased the resistance to rainfall and ability to grow plant on the surface for improved soil.

Creation of an Environmental Forest as an Ecological Restoration

  • Lee, Chang-Seok;You, Young-Han
    • The Korean Journal of Ecology
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    • v.24 no.2
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    • pp.101-109
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    • 2001
  • We created an environmental forest on the basis of ecological design around the incineration plant of Jindo Engineering and Construction Co., Ltd., which is located in Jeongwang-dong, Siheung-si, Kyunggi-do. To get ecological information of this site, physico-chemical properties of soil on salt marsh, which is located close to the syudy site and of forest soil transported from other sites for ecological restoration were analyzed. Texture of salt marsh and transported soils were loam and sandy loam, respectively. pH, organic matter, T-N, available P, and exchangeable K and Na contents of salt marsh and transported forest soils were 6.7 and 5.4, 4.1 and 0.4%, 1.0 and 0.3mg/g, 46.7 and 6.8ppm, 521 and 207ppm, and 3.8 and 0.5mg/g, respectively. Introduced plants were selected among the dominant species of forests and the species composing the potential natural vegetation around the present study site. Those plants were selected again by considering the tolerances to air pollution and to salt, and their availability. Selected trees were Pinus thunbergii, Sophora japonica, Celtis sinensis, Quercus aliena, Q. serrata, Q. dentata, and Q. acutissima. Selected sub-trees were Albizzia julibrissin, Koelreuteria poniculata, and Styrax japonica and shrubs were Rhododendron yedoense var. poukhanense, R. mucronulatum, Callicarpa japonica, Euonymus alatus, E. japonica, and R. schlippenbachii. On the other hand, introduction of herbs was not considered except for Liriope platyphylla, which was ornamentally planted in one site. Planting bed of mound type was adopted to provide the fine drainage system. Mound was designed to furnish litter, A, B, and C layers simuating the profile of forest soil. Slope of mound was mulched by rice straw of 2cm in thickness to prevent for sliding of litter and soil in cases of strong wind or heavy rain. Height of mound was designed to secure more than 1 m by combining A and B layers. Narrow zones, in which mound with stable slope degree cannot be prepared, was designed to equip the standard soil depth with the introduction of stone for supporting. On the other hand, plants with shallow root system were arranged in some zones, in which satisfactory soil depth cannot be ensured. Plants were arranged in the order of tree, sub-tree, and shrub from center to edge on the mound to make a mature forest of a dome shape in the future. Dispersion of plants was designed to be random pattern rather than clumped one. Problems on creation of the environmental forest by such ecological design were found to be management or inspection by non-specialized project operators and inspecting officers, and regulations for construction without ecological background. Alternative plans to solve such problems were suggested.

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A Study on the Effect of Mobile CCTV Monitoring on Safety Risk Factors (안전 Risk 요인에 대한 이동형 CCTV 모니터링이 미치는 영향 연구)

  • Young Cheol Song;Tae-Gon Kim;Eunseok Lee;Tae-Hun Kim
    • Industry Promotion Research
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    • v.9 no.1
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    • pp.39-45
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    • 2024
  • Dangerous tasks that occur every day at industrial site manufacturing plants, which have recently been making rapid changes, were classified by type, and the effect of mobile circuit television (CCTV) on safety accidents among daily safety management methods was analyzed. The subject of the study is about 3,000 workers who manage the infrastructure facility sector to supply utilities such as gas, water, and electricity to the display manufacturing process located in Asan City, and the study was conducted based on the daily dangerous work from 2019 to 2022, and during this study period, many construction works such as new investment and expansion of construction and manufacturing processes were occurring at the site. As a result, the rate of safety accidents and exposure to risks are expanding, and most of the safety accidents occurred because the sectors that did not follow the basics and the safety measures on the site were not implemented. In this paper, it was confirmed that there is an accident reduction effect according to the relationship between the dangerous work classified according to the work importance and the mobile CCTV shooting rate. Considering the characteristics of the manufacturing plant site, it can be used to play the role of basic data for preventing safety accidents based on the expansion of the introduction of a new safety management culture in the future.

A novel method for high-frequency genome editing in rice, using the CRISPR/Cas9 system (벼에서 CRISPR/Cas9 활용 고빈도 유전자 편집 방법)

  • Jung, Yu Jin;Bae, Sangsu;Lee, Geung-Joo;Seo, Pil Joon;Cho, Yong-Gu;Kang, Kwon Kyoo
    • Journal of Plant Biotechnology
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    • v.44 no.1
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    • pp.89-96
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    • 2017
  • The CRISPR/Cas9 is a core technology that can result in a paradigm for breeding new varieties. This study describes in detail the sgRNA design, vector construction, and the development of a transgenic plant and its molecular analysis, and demonstrates how gene editing technology through the CRISPR/Cas9 system can be applied easily and accurately. CRISPR/Cas9 facilitates targeted gene editing through RNA-guided DNA cleavage, followed by cellular DNA repair mechanisms that introduce sequence changes at the site of cleavage. It also allows the generation of heritable-targeted gene mutations and corrections. Here, we present detailed procedures involved in the CRISPR/Cas9 system to acquire faster, easier and more cost-efficient gene edited transgenic rice. The protocol described here establishes the strategies and steps for the selection of targets, design of sgRNA, vector construction, and analysis of the transgenic lines. The same principles can be used to customize the versatile CRISPR/Cas9 system, for application to other plant species.

Performance Evaluation System for Construction Environment of the Unified Waterproofing-Root Resistance Membrane layer of the Green Roof System (인공지반 녹화용 방수방근 복합공법의 시공환경을 고려한 성능평가 시스템 연구)

  • Park, Chang-Hwa;Oh, Sang-Keun;Lim, Nam-Gi
    • Journal of the Korea Institute of Building Construction
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    • v.11 no.2
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    • pp.189-199
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    • 2011
  • Installation of a proper root barrier in a green roof system is very important in order to protect the concrete slab of roof and the root penetration in the waterproofing layer. To select the proper root barrier materials and methods, it is necessary to understand the environmental conditions affecting the waterproofing-root barrier system in green roof construction site. Therefore, we suggested as the environmental performance indexes four kinds of performance requirements; root penetration, chemical attack by chemical agent or fertilizer, load impact by soil depth and size of plant, and water pressure. The related four test methods were suggested for the inspection of these performance indexes. In this research, we could suggest for kinds of test methods as standard test methods to evaluate the environmental performance of waterproofing-root barrier for greening roof system.

Evaluation on the Mechanical Properties of Strain Hardening Cement Composite by Mixing Method for Application at Building Construction Site (건축시공 현장적용을 위한 비빔방법에 따른 SHCC의 역학적 성능 평가)

  • Jeon, Young-Seok;Kim, Gyu-Yong;Nam, Jeong-Soo;Kim, Young-Deok;Jeong, Jae-Hong;Lee, Seung-Hoon
    • Journal of the Korea Institute of Building Construction
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    • v.11 no.6
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    • pp.530-537
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    • 2011
  • The purpose of this study is to examine material performance of fiber reinforced cement composite for mass production. It is necessary to manufacture SHCC(Strain Hardening Cement Composite) by batch plant for field application and mass production. For the study, a mock-up test of SHCC manufactured in the batch plant was conducted, and the performance was compared with SHCC manufactured in the laboratory. Assessment items were freshness and hardening properties. Specifically, direct tensile test machine was used for performance verification of SHCC. As a result, there was a tendency of less satisfactory fiber dispersion and performance of strain hardening compared with the performance of SHCC manufactured in the laboratory. To address this, dry mixing and mortar mixing time should be increased compared to laboratory mixing, and injection time of an agent such as a water reducing agent should be properly controlled according to mixing combination, or the capacity to secure dispersion and homogeneity of material.

A prognosis discovering lethal-related genes in plants for target identification and inhibitor design (식물 치사관련 유전자를 이용하는 신규 제초제 작용점 탐색 및 조절물질 개발동향)

  • Hwang, I.T.;Lee, D.H.;Choi, J.S.;Kim, T.J.;Kim, B.T.;Park, Y.S.;Cho, K.Y.
    • The Korean Journal of Pesticide Science
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    • v.5 no.3
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    • pp.1-11
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    • 2001
  • New technologies will have a large impact on the discovery of new herbicide site of action. Genomics, combinatorial chemistry, and bioinformatics help take advantage of serendipity through tile sequencing of huge numbers of genes or the synthesis of large numbers of chemical compounds. There are approximately $10^{30}\;to\;10^{50}$ possible molecules in molecular space of which only a fraction have been synthesized. Combining this potential with having access to 50,000 plant genes in the future elevates tile probability of discovering flew herbicidal site of actions. If 0.1, 1.0 or 10% of total genes in a typical plant are valid for herbicide target, a plant with 50,000 genes would provide about 50, 500, and 5,000 targets, respectively. However, only 11 herbicide targets have been identified and commercialized. The successful design of novel herbicides depends on careful consideration of a number of factors including target enzyme selections and validations, inhibitor designs, and the metabolic fates. Biochemical information can be used to identify enzymes which produce lethal phenotypes. The identification of a lethal target site is an important step to this approach. An examination of the characteristics of known targets provides of crucial insight as to the definition of a lethal target. Recently, antisense RNA suppression of an enzyme translation has been used to determine the genes required for toxicity and offers a strategy for identifying lethal target sites. After the identification of a lethal target, detailed knowledge such as the enzyme kinetics and the protein structure may be used to design potent inhibitors. Various types of inhibitors may be designed for a given enzyme. Strategies for the selection of new enzyme targets giving the desired physiological response upon partial inhibition include identification of chemical leads, lethal mutants and the use of antisense technology. Enzyme inhibitors having agrochemical utility can be categorized into six major groups: ground-state analogues, group specific reagents, affinity labels, suicide substrates, reaction intermediate analogues, and extraneous site inhibitors. In this review, examples of each category, and their advantages and disadvantages, will be discussed. The target identification and construction of a potent inhibitor, in itself, may not lead to develop an effective herbicide. The desired in vivo activity, uptake and translocation, and metabolism of the inhibitor should be studied in detail to assess the full potential of the target. Strategies for delivery of the compound to the target enzyme and avoidance of premature detoxification may include a proherbicidal approach, especially when inhibitors are highly charged or when selective detoxification or activation can be exploited. Utilization of differences in detoxification or activation between weeds and crops may lead to enhance selectivity. Without a full appreciation of each of these facets of herbicide design, the chances for success with the target or enzyme-driven approach are reduced.

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A Study on Landscaping Repair Work Classifications in Cultural Heritage Industry (문화재 수리의 조경분야 공종 분류에 관한 연구)

  • Kim, Min-Seon;Lee, Jae-Yong;Kim, Choong-Sik
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.40 no.2
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    • pp.59-66
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    • 2022
  • The purpose of this study was to suggest the landscaping repair work classification, the standard for securing the independence of and establishing the scope of landscaping repair works. Standard construction specifications currently specify the landscaping repair work classification around the planting construction, while standard work estimate does not include the field of landscaping. The landscaping construction specifications and the standard work estimate in the construction industry should be, however, applied, so it is difficult to specifically understand what is the landscaping repair work classification in the cultural heritage industry. From 1961 to 1980, not only the tree planting but also a variety of landscaping facilities had been specified as the landscaping repair works, and it was found that all of these work classifications are established as the landscaping repair work classifications in the construction industry. A total of 20 work classifications were verified by comprehensively arranging those specified in notices of tender for working drawing services for cultural heritages during three years, from 2018 to 2020, except for those for the maintenance and Dancheong of architectures, plant protection and conservation. All 20 work classifications corresponded to the landscaping work classifications in the construction industry. On the basis of the landscaping work classifications in the construction industry, this study divided the landscaping repair work classifications into site-building and shaping, planting work, facility construction, paving work, ecological landscape architectural construction and vegetation maintenance, by considering the specialty of cultural heritage space.

Tunneling in Severe Groundwater Inflow Condition (지하수 과다유입 조건하에서의 터널굴착)

  • Lee, Young-Nam;Kim, Dae-Young
    • Journal of the Korean GEO-environmental Society
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    • v.7 no.2
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    • pp.67-76
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    • 2006
  • For a hydro power plant project, the headrace tunnel having a finished diameter of 3.3 m was constructed in volcanic rocks with well-developed vertical joint and high groundwater table. The intake facility was located 20.3km upstream of the powerhouse and headrace tunnel of 20km in length and penstock of 440m in height connected the intake and the powerhouse. The typical caldera lake, Lake Toba set the geology at the site the caving of the ground caused tension cracks in the vertical direction to be developed and initial stresses at the ground to be released. High groundwater table(the maximum head of 20bar) in the area of well-connected vertical joints delayed the progress of tunnel excavation severely due to the excessive inflow of groundwater. The excavation of tunnel was made using open-shield type TBM and mucking cars on the rail. High volume of water inflowraised the water level inside tunnel to 70cm, 17% of tunnel diameter (3.9m) and hindered the mucking of spoil under water. To improve the productivity, several adjustments such as modification of TBM and mucking cars and increase in the number of submersible pumps were made forthe excavation of severe water inflow zone. Since the ground condition encountered during excavation turned out to be much worse, it was decided to adopt PC segment lining instead of RC lining. Besides, depending on the conditions of the water inflow, rock mass condition and internal water pressure, one of the invert PC segment lining with in-situ RC lining, RC lining and steel lining was applied to meet the site specific condition. With the adoption of PC segment lining, modification of TBM and other improvement, the excavation of the tunnel under severe groundwater condition was successfully completed.

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