• Title/Summary/Keyword: Small Construction

Search Result 2,488, Processing Time 0.032 seconds

A Study on the Status and Performance of Cultural Heritage in the Demilitarized Zone on the Korean Peninsula (한반도 비무장지대 문화유산의 실태조사 현황과 성과 고찰)

  • HWANGBO Kyung
    • Korean Journal of Heritage: History & Science
    • /
    • v.57 no.2
    • /
    • pp.28-50
    • /
    • 2024
  • A fact-finding survey of the Demilitarized Zone can be said to be a very meaningful academic survey linked to previous index surveys of protected military areas and municipal and excavation surveys of ruins and military sites on Mount Dora. Not a few ruins were first discovered in this survey, and the locations, structures, and restoration artifacts of the previously investigated ruins were confirmed differently, raising the need for a detailed investigation. In particular, it is noteworthy that various relics from the Paleolithic Age to the Joseon Dynasty were recovered from relics dispersion sites such as Josan-ri and Cheorwon Gangseo-ri in Paju, and Hoengsan-ri Temple Site is also a Buddhist relic in the Demilitarized Zone. However, in the case of some graveyards and relics sites in the Paju region, it was an opportunity to understand the reality that they are not safe from cultivation and development, and the ruins of Cheorwon Capital Castle, Seongsanseong Fortress, Jorangjin Bastion, and Gangseo-ri Bastion were damaged during the construction of military facilities, and an urgent investigation is needed. Also, farmland and hilly areas around the ruins of Jangdan, Gunnae-myeon, and Gangsan-ri have not been properly investigated for buried cultural assets due to small-scale development. Therefore, it is an important time for the relevant authorities and agencies to cooperate more closely to establish special management and medium- to long-term investigation measures for the cultural heritage in the Demilitarized Zone based on the results of this fact-finding investigation.

Research on Bridge Maintenance Methods Using BIM Model and Augmented Reality (BIM 모델과 증강현실을 활용한 교량 유지관리방안 연구)

  • Choi, Woonggyu;Pa Pa Win Aung;Sanyukta Arvikar;Cha, Gichun;Park, Seunghee
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.44 no.1
    • /
    • pp.1-9
    • /
    • 2024
  • Bridges, which are construction structures, have increased from 584 to 38,405 since the 1970s. However, as the number of bridges increases, the number of bridges with a service life of more than 30 years increases to 21,737 (71%) by 2030, resulting in fatal accidents due to basic human resource maintenance of facilities. Accordingly, the importance of bridge safety inspection and maintenance measures is increasing, and the need for decision-making support for supervisors who manage multiple bridges is also required. Currently, the safety inspection and maintenance method of bridges is to write down damage, condition, location, and specifications on the exterior survey map by hand or to record them by taking pictures with a camera. However, errors in notation of damage or defects or mistakes by supervisors are possible, typos, etc. may reduce the reliability of the overall safety inspection and diagnosis. To improve this, this study visualizes damage data recorded in the BIM model in an AR environment and proposes a maintenance plan for bridges with a small number of people through maintenance decision-making support for supervisors.

Analysis of Applicability of Rapid Hardening Composite Mat to Railway Sites (초속경 복합매트의 철도현장 적용성 분석)

  • Jang, Seong Min;Yoo, Hyun Sang;Oh, Dong Wook;Batchimeg, Banzragchgarav;Jung, Hyuk Sang
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.44 no.1
    • /
    • pp.109-116
    • /
    • 2024
  • The Rapid Hardening Composite Mat (RHCM) is a product that improves the initial strength development speed of conventional Geosynthetic Cementitious Composite Mats (GCCM). It offers the advantage of quickly securing sufficient strength in railway slopes with insufficient formation level, and provides benefits such as preventing slope erosion and inhibiting vegetation growth. In this study, an analysis of the practical applicability of RHCM in railway settings was conducted through experimentation. The on-site applicability was assessed by categorizing it into fire resistance, durability, and stability, and conducting combustibility test, ground contact pressure test, and daily displacement analyses. In the case of South Korea, where a significant portion of the territory is composed of forested areas, the prevention of slope fires is imperative. To analyze the fire resistance of RHCM, combustibility tests were conducted as an essential measure. Durability was assessed through ground contact pressure tests to analyze the deformation and potential damage of RHCM caused by the inevitable use of small to medium-sized equipment on the construction surface. Furthermore, daily displacement analysis was conducted to evaluate the structural stability by comparing and analyzing the displacement and behavior occurring during the application of RHCM with railway slope maintenance criteria. As a result of the experiments, the RHCM was analyzed to meet the criteria for heat release rate and gas toxicity. Furthermore, the ground contact pressure was observed to be consistently above 50 kPa during the curing period of 4 to 24 hours under all conditions. Additionally, the daily displacement analyzed through field site experiments ranged from -1.7 mm to 1.01 mm, confirming compliance with the criteria.

Evaluation of Hydrogeological Characteristics of Deep-Depth Rock Aquifer in Volcanic Rock Area (화산암 지역 고심도 암반대수층 수리지질특성 평가)

  • Hangbok Lee;Chan Park;Junhyung Choi;Dae-Sung Cheon;Eui-Seob Park
    • Tunnel and Underground Space
    • /
    • v.34 no.3
    • /
    • pp.231-247
    • /
    • 2024
  • In the field of high-level radioactive waste disposal targeting deep rock environments, hydraulic characteristic information serves as the most important key factor in selecting relevant disposal sites, detailed design of disposal facilities, derivation of optimal construction plans, and safety evaluation during operation. Since various rock types are mixed and distributed in a small area in Korea, it is important to conduct preliminary work to analyze the hydrogeological characteristics of rock aquifers for various rock types and compile the resulting data into a database. In this paper, we obtained hydraulic conductivity data, which is the most representative field hydraulic characteristic of a high-depth volcanic bedrock aquifer, and also analyzed and evaluated the field data. To acquire field data, we used a high-performance hydraulic testing system developed in-house and applied standardized test methods and investigation procedures. In the process of hydraulic characteristic data analysis, hydraulic conductivity values were obtained for each depth, and the pattern of groundwater flow through permeable rock joints located in the test section was also evaluated. It is expected that the series of data acquisition methods, procedures, and analysis results proposed in this report can be used to build a database of hydraulic characteristics data for high-depth rock aquifers in Korea. In addition, it is expected that it will play a role in improving technical know-how to be applied to research on hydraulic characteristic according to various bedrock types in the future.

Construction of a Plant Chloroplast Transformation Vector to Produce the Antimicrobial Peptide Stomoxyn (대장균에서 항균 펩타이드 stomoxyn을 생산하기 위한 형질전환 벡터 제작)

  • Jin Gyu Go;Hyeon Ho Gil;Soon Young Kim
    • Journal of Life Science
    • /
    • v.34 no.7
    • /
    • pp.493-499
    • /
    • 2024
  • Antimicrobial peptides are antimicrobial substances inherent in animals and plants, with strong antibacterial activity even in small amounts and with various other functions such as antiviral and antioxidant actions. Plants can be grown with just water and sunlight, allowing for their mass production at low costs. However, transforming a chloroplast into one that produces antimicrobial peptides, rather than growing plants, increases the amount of protein expression and minimizes contamination of the ecosystem because gene transfer by pollen does not occur. In that context, using transgenic plant chloroplasts to produce recombinant proteins increases protein degradation and reduces the solubility of proteins. To solve this problem, we fused SUMO, a fusion protein, with a recombinant protein. We also used a 6xHis tag to purify the fusion protein. The antimicrobial peptide stomoxyn is an antibacterial substance found in stable flies. Stomoxyn has an α-helix structure and is amphiphilic, which allows it to dissolve bacterial cell membranes. In this study, we constructed a transformation vector to express stomoxyn in both plant chloroplasts and Escherichia coli and used this vector to confirm the expression of stomoxyn in E. coli. The expression of the protein was then confirmed in E. coli using a transformation vector. The expressed stomoxyn was purified by nickel column and SUMOase treatment, and its antibacterial activity was confirmed using an agar diffusion assay. The EGFP gene was used to ensure that the transformed vector was inserted into the chloroplast.

NUWARD SMR safety approach and licensing objectives for international deployment

  • D. Francis;S. Beils
    • Nuclear Engineering and Technology
    • /
    • v.56 no.3
    • /
    • pp.1029-1036
    • /
    • 2024
  • Drawing on the deep experience and understanding of the principles of nuclear safety, as well as many years of nuclear power plant design and operation, the EDF led NUWARD SMR Project is developing a design for a Small Modular Reactor (SMR) of 340 MWe composed of two 170 MWe independent units, that will supplement the offering of high-output nuclear reactors, especially in response to specific needs such as replacement of fossil-fuelled power plants. NUWARD SMR is a mix of proven and innovative design features that will make it more commercially competitive, while integrating safety features that comply with the highest international standards. Following the principles of redundancy and diversity and rigorous application of Defence in Depth (DID), with an international view on nuclear safety licensing, the Project also incorporates new safety approaches into its design development. The NUWARD SMR Project has been in development for a number of years, it entered conceptual design formally in mid-2019 and entered Basic Design in 2023. The objective of the concept design phase was to confirm the project technological choices and to define the first design configuration of the NUWARD SMR product, to document it, in order to launch pre-licensing with the French Safety Authority (ASN) and to define its estimated cost and its subsequent development and construction schedules. As a delivery milestone the Safety Options file (called the Dossier d'Options de Sûreté (DOS)) has been submitted to ASN in July 2023 for their opinion. An integral part of the NUWARD SMR Project, is not only to deliver a design suitable for France and to satisfy French regulation, but to develop a product suitable and indeed desirable, for the international market, with a first focus in Europe. In order to achieve its objectives and realise its market potential, the NUWARD SMR Project needs to define and realise its safety approach within an international environment and that is the key subject of this paper. The following paper: • Summarises the foundation principles and technological background which underpin the design; • Contextualises the key design features with regard to the international safety regulatory framework with particular emphasis on innovative passive safety aspects; • Illustrates the Project activities in preparation for first licensing in France, and also a wider international view via the ASN led Joint Early Review of the NUWARD SMR design, including Finnish and Czech Republic regulators, recently joined by the Swedish, Polish and Dutch regulators; • Articulates the collaborative approach to design development from involvement with the Project partners (the Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Naval Group, TechnicAtome, Framatome and Tractebel) to the establishment of the International NUWARD Advisory Board (INAB), to gain greater international insight and advice; • Concludes with the focus on next steps into detailed design development, standardisation of the design and its simplification to enhance its commercial competitiveness in a context of further harmonisation of the nuclear safety and licensing requirements and aspirations.

Single-Channel Seismic Data Processing via Singular Spectrum Analysis (특이 스펙트럼 분석 기반 단일 채널 탄성파 자료처리 연구)

  • Woodon Jeong;Chanhee Lee;Seung-Goo Kang
    • Geophysics and Geophysical Exploration
    • /
    • v.27 no.2
    • /
    • pp.91-107
    • /
    • 2024
  • Single-channel seismic exploration has proven effective in delineating subsurface geological structures using small-scale survey systems. The seismic data acquired through zero- or near-offset methods directly capture subsurface features along the vertical axis, facilitating the construction of corresponding seismic sections. However, substantial noise in single-channel seismic data hampers precise interpretation because of the low signal-to-noise ratio. This study introduces a novel approach that integrate noise reduction and signal enhancement via matrix rank optimization to address this issue. Unlike conventional rank-reduction methods, which retain selected singular values to mitigate random noise, our method optimizes the entire singular value spectrum, thus effectively tackling both random and erratic noises commonly found in environments with low signal-to-noise ratio. Additionally, to enhance the horizontal continuity of seismic events and mitigate signal loss during noise reduction, we introduced an adaptive weighting factor computed from the eigenimage of the seismic section. To access the robustness of the proposed method, we conducted numerical experiments using single-channel Sparker seismic data from the Chukchi Plateau in the Arctic Ocean. The results demonstrated that the seismic sections had significantly improved signal-to-noise ratios and minimal signal loss. These advancements hold promise for enhancing single-channel and high-resolution seismic surveys and aiding in the identification of marine development and submarine geological hazards in domestic coastal areas.

Simplistic Beam Theory-based Structural Safety Evaluation Method for Block Structure on the A-Carrier (블록 구조물 적치용 지지대의 빔 이론 기반 구조 안전성 평가법)

  • Myung-Su Yi;Joo-Shin Park
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.30 no.4
    • /
    • pp.358-364
    • /
    • 2024
  • Type A carrier structures that support blocks or equipment gradually deform over time with load changes, reducing the area in contact with the block and changing the load pattern from distributed to concentrated during construction work in the shipyard. This phenomenon has the potential to misrepresent actual service loads. In particular, A carriers are often used by small manufacturers, who often do not have specialized engineering capabilities, necessitating the development of a method for easy calculation of carrier safe working load. This study proposes a quick evaluation method for the long-term safe working load of Type A carriers, to predict the plastic deformation and safety issues resulting from changes in load distribution. Based on the results of finite element analysis (beam and shell modeling) of the centralized load, beam-theory was modified to propose a method for determining the distributed load conditions of the A-carrier. In beam modeling, the theoretical value was multiplied by a correction factor of 0.73 for concentrated loads and 0.69 for distributed loads to obtain a safe working load. For shell modeling, a correction factor of 0.75 can be used for concentrated loads and 0.69 for distributed loads. This study can serve as a basis for improving the safety of shipbuilding, enabling quick and effective decisions for determining safe working loads in actual working environments.

Construction of cDNA Library for Using Virus-induced Gene Silencing (VIGS) Vector with the Sweetpotato Whitefly, Bemisia tabaci(Hemiptera: Aleyrodidae) (담배가루이(Bemisia tabaci, Aleyrodidae, Hemiptera)에서 Virus-induced Gene Silencing (VIGS) Vector를 이용하기 위한 cDNA Library 제작)

  • Ko, Na Yeon;Lim, Hyoun Sub;Yu, Yong Man;Youn, Young Nam
    • Korean journal of applied entomology
    • /
    • v.54 no.2
    • /
    • pp.91-97
    • /
    • 2015
  • The sweetpotato whitefly, Bemisia tabaci, is the major insect pest that transmitted over 100 plant viruses including tomato yellow leaf curl virus (TYLCV) of tomato plant as virus vector in the world. In this study, cDNA library of whitefly was constructed using Gateway system for selecting target gene in order to control of B. tabaci using virus-induced gene silencing (VIGS) vector with RNAi. First of all, when using oligo d(T) rimer, the calculated titer of cDNA library was confirmed with $1.4{\times}10^4$ clones and average insert sizes was confirmed with 1 kb. However, insert size was very big for construction of cDNA. Otherwise, when using attB-N25 random primer and sonication for 6 sec, the calculated titer of cDNA library was confirmed with $1.04{\times}10^5$ clones. But mostly insert band wasn't identified on the electrophoresis, because it seemed that insert size is too small (${\leq}100bp$), also the size of identified insert was somewhat big. Finally, when using oligo d(T) primer and sonication for 1 sec, cDNA insert of whitefly was appropriated for VIGS with 300-600 bp. However, cDNA sequence included a poly A and titer was very low to $5.2{\times}10^2$ clones. It was supposed that heat shock transformation was used instead of electro-transformation. It is considered that when constructing cDNA library for using VIGS vector, (1) random primer should be used for First strand cDNA synthesis in order to remove poly A and (2) sonication for 1 sec should be performed in order to get appropriated insert size and (3) electro-transformation should be performed in order to improve transformation efficiency.

A Study on the Conservation and Management of the Village Forest in Gyeonggi-do (경기도 마을숲의 보전 및 관리에 관한 연구)

  • Hwang, Dong-Kyu;Kim, Dong-Yeob
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.33 no.4
    • /
    • pp.99-111
    • /
    • 2015
  • The objectives of this study were to investigate the location, shape, environment, and vegetation of the Village Forest in Gyeonggi-do and to evaluate the ecological integration and changes of the Village Forests to figure out the measures for conservation and management. There were 23 Village Forests remain in Gyeonggi-do. Ten Village Forests were established based on Feng-shui background. Many of them were found in Yongin area and southeast of Icheon. The Village Forests were owned by local community at 9 village and privately owned at 8 villages. Most Village Forests were managed by local communities except for the two managed by private person. Fifty-two percent of the Village Forests were in strip shape, and most of them were established by Feng-shui background or for the prevention of disasters. The average size of the Village Forests was relatively small at 3,046m2. The most frequent tree species found at the Village Forest were Zelkova serrata and Pinus densiflora. Over half of the number of Village Forests showed vertical structure of overstory trees only or overstory-sub overstory combination, which seemed to be resulted from the loss of understory plants by the activities of local residents. The Village Forests that had over 30% of damaged trees were found at 7 villages. The damages were caused by the road construction close to the groves, soil compaction, and tree death by covering lower stem with soil. The vitality of the damaged trees seemed to be significantly low compared to that of the undamaged. There were factors that determined the changes in the Village Forests: community ritual, institutional protection, designation as a water resource protection district, road construction, land use change, windstorm hazards, and development of forest areas. In order to conserve and manage the Village Forests appropriately, it is necessary to limit excessive use of the grove areas and maintain proper tree growing conditions by improving the soil environment. The development of neighborhood areas need to be controlled and community activities should be encouraged to maintain or restore the original landscape of the groves. Protection measures and supporting policies need to be enforced to keep the Village Forests from disappearing in near future.