• Title/Summary/Keyword: Field engineering

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A Study on the Structural Reinforcement of the Modified Caisson Floating Dock (개조된 케이슨 플로팅 도크의 구조 보강에 대한 연구)

  • Kim, Hong-Jo;Seo, Kwang-Cheol;Park, Joo-Shin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.1
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    • pp.172-178
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    • 2021
  • In the ship repair market, interest in maintenance and repair is steadily increasing due to the reinforcement of prevention of environmental pollution caused by ships and the reinforcement of safety standards for ship structures. By reflecting this effect, the number of requests for repairs by foreign shipping companies increases to repair shipbuilders in the Southwest Sea. However, because most of the repair shipbuilders in the southwestern area are small and medium-sized companies, it is difficult to lead to the integrated synergy effect of the repair shipbuilding companies. Moreover, the infrastructure is not integrated; hence, using the infrastructure jointly is a challenge, which acts as an obstacle to the activation of the repair shipbuilding industry. Floating docks are indispensable to operating the repair shipbuilding business; in addition, most of them are operated through renovation/repair after importing aging caisson docks from overseas. However, their service life is more than 30 years; additionally, there is no structure inspection standard. Therefore, it is vulnerable to the safety field. In this study, the finite element analysis program of ANSYS was used to evaluate the structural safety of the modified caisson dock and obtain additional structural reinforcement schemes to solve the derived problems. For the floating docks, there are classification regulations; however, concerning structural strength, the regulations are insufficient, and the applicability is inferior. These insufficient evaluation areas were supplemented through a detailed structural FE-analysis. The reinforcement plan was decided by reinforcing the pontoon deck and reinforcement of the side tank, considering the characteristics of the repair shipyard condition. The final plan was selected to reinforce the side wing tank through the structural analysis of the decision; in addition, the actual structure was fabricated to reflect the reinforcement plan. Our results can be used as reference data for improving the structural strength of similar facilities; we believe that the optimal solution can be found quickly if this method is used during renovation/repair.

Study on Ti-doped LiNi0.6Co0.2Mn0.2O2 Cathode Materials for High Stability Lithium Ion Batteries (고안정성 리튬이온전지 양극활물질용 Ti 치환형 LiNi0.6Co0.2Mn0.2O2 연구)

  • Jeon, Young Hee;Lim, Soo A
    • Journal of the Korean Electrochemical Society
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    • v.24 no.4
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    • pp.120-132
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    • 2021
  • Although the development of high-Nickel is being actively carried out to solve the capacity limitation and the high price of raw cobalt due to the limitation of high voltage use of the existing LiCoO2, the deterioration of the battery characteristics due to the decrease in structural stability and increase of the Ni content. It is an important cause of delaying commercialization. Therefore, in order to increase the high stability of the Ni-rich ternary cathod material LiNi0.6Co0.2Mn0.2O2, precursor Ni0.6Co0.2Mn0.2-x(OH)2/xTiO2 was prepared using a nanosized TiO2 suspension type source for uniform Ti substitution in the precursor. It was mixed with Li2CO3, and after heating, the cathode active material LiNi0.6Co0.2Mn0.2-xTixO2 was synthesized, and the physical properties according to the Ti content were compared. Through FE-SEM and EDS mapping analysis, it was confirmed that a positive electrode active material having a uniform particle size was prepared through Ti-substituted spherical precursor and Particle Size Analyzer and internal density and strength were increased, XRD structure analysis and ICP-MS quantitative analysis confirmed that the capacity was effectively maintained even when the Ti-substituted positive electrode active material was manufactured and charging and discharging were continued at high temperature and high voltage.

Science and Technology ODA Promotion of Korea through ICT of Global Problem Solving Centers -Suggestion on the mid- and short-term projects promotion of science and technology ODA roadmap- (글로벌문제해결거점 ICT화를 통한 한국형 과학기술 ODA 추진 -과학기술 ODA 중·단기 과제 추진에 대한 제언-)

  • Jung, Woo-Kyun;Shin, Kwanwoo;Jeong, Seongpil;Park, Hunkyun;Park, Eun Sun;Ahn, Sung-Hoon
    • Journal of Appropriate Technology
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    • v.7 no.2
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    • pp.162-171
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    • 2021
  • The Korean government proposed the K-SDGs in 2019 to promote the UN SDGs, but the role and tasks of science and technology, an important means of implementing the SDGs, have not been materialized. Accordingly, the role of science and technology ODA for the SDGs was established through the Ministry of Science and ICT's policy research project 'Science and Technology ODA Promotion Roadmap for Spreading the New Southern Policy and Realizing the 2030 SDGs'. In addition, goals, strategies, and core tasks for the next 10 years were derived in 10 fields such as water, climate change, energy, and ICT. In this paper, we analyze 30 key tasks of the ODA promotion roadmap for science and technology for the realization of SDGs, and propose mid- and short-term tasks and implementation plans for effective roadmap promotion. Among the key tasks in each field, four common elements were derived: ICT/smartization, a global problem-solving center, cooperation/communication platform, and business model/startup support platform/living lab that can create and integrate roadmap implementation conditions. In addition, the four mid- and short-term tasks, 1) Establishment of science and technology ODA network, 2) Establishment of living lab business platform linked to start-up support business, 3) Local smartization of recipient countries, and 4) Expand and secure sustainability of global problem-solving centers, were set in relation to the implementation of the detailed roadmap. For the derived mid- and short-term tasks, detailed implementation plans based on the ICTization of global problem-solving centers were presented. The implementation of the mid- and short-term tasks presented in this paper can contribute to the more effective achievement of the science and technology ODA roadmap, and it is expected that Korea's implementation of SDGs will also achieve high performance.

Soil CO2 Monitoring Around Wells Discharging Methane (메탄 유출 관정 주변의 토양 CO2 모니터링)

  • Chae, Gitak;Kim, Chan Yeong;Ju, Gahyeun;Park, Kwon Gyu;Roh, Yul;Lee, Changhyun;Yum, Byoung-Woo;Kim, Gi-Bae
    • Economic and Environmental Geology
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    • v.55 no.4
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    • pp.407-419
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    • 2022
  • Soil(vadose zone) gas compositions were measured for about 3 days to suggest a method for monitoring and interpreting soil gas data collected around wells from which methane(CH4) is outflowing. The vadose zone gas samples were collected within 1 m around two test wells(TB2 and TB3) at Pohang and analyzed for CO2, CH4, N2 and O2 concentrations in situ. CO2 flux was measured beside TB2. In addition, gas samples from well head in TB2 and atmospheric air samples were collected for comparison. Carbon isotopes of CO213CCO2) of samples collected on the last day of the study period were analyzed in the laboratory. The two test wells (TB2 and 3) were 12.7 m apart and only TB3 was cemented to the surface. According to the bio-geochemical process-based interpretation, the relationships between CO2 and O2, N2, and N2/O2 of vadose zone gas were plotted between the lines of CH4 oxidation and CO2 dissolution. In addition, the CH4 concentrations of gas samples from the wellhead of the uncemented well (TB2) were 5.2 times higher than the atmospheric CH4 concentration. High CO2 concentrations (average 1.148%) of vadose zone gas around TB2 seemed to be attributed to the oxidation of CH4. On the other hand, the vadose zone CO2 around the cemented well(TB3) showed a relatively low concentration(0.136%). This difference indicates that the vadose zone gas(including CO2) around the CH4 outflowing well were strongly affected by well completion(cementing). This study result can be used to establish strategies for environmental monitoring of soil around natural gas sites, and can be used to monitor leakage around injection and observation wells for CO2 geological storage. In addition, the method of this study is useful for soil monitoring in natural gas storage and oil-contaminated sites.

Prediction of Acer pictum subsp. mono Distribution using Bioclimatic Predictor Based on SSP Scenario Detailed Data (SSP 시나리오 상세화 자료 기반 생태기후지수를 활용한 고로쇠나무 분포 예측)

  • Kim, Whee-Moon;Kim, Chaeyoung;Cho, Jaepil;Hur, Jina;Song, Wonkyong
    • Ecology and Resilient Infrastructure
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    • v.9 no.3
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    • pp.163-173
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    • 2022
  • Climate change is a key factor that greatly influences changes in the biological seasons and geographical distribution of species. In the ecological field, the BioClimatic predictor (BioClim), which is most related to the physiological characteristics of organisms, is used for vulnerability assessment. However, BioClim values are not provided other than the future period climate average values for each GCM for the Shared Socio-economic Pathways (SSPs) scenario. In this study, BioClim data suitable for domestic conditions was produced using 1 km resolution SSPs scenario detailed data produced by Rural Development Administration, and based on the data, a species distribution model was applied to mainly grow in southern, Gyeongsangbuk-do, Gangwon-do and humid regions. Appropriate habitat distributions were predicted every 30 years for the base years (1981 - 2010) and future years (2011 - 2100) of the Acer pictum subsp. mono. Acer pictum subsp. mono appearance data were collected from a total of 819 points through the national natural environment survey data. In order to improve the performance of the MaxEnt model, the parameters of the model (LQH-1.5) were optimized, and 7 detailed biolicm indices and 5 topographical indices were applied to the MaxEnt model. Drainage, Annual Precipitation (Bio12), and Slope significantly contributed to the distribution of Acer pictum subsp. mono in Korea. As a result of reflecting the growth characteristics that favor moist and fertile soil, the influence of climatic factors was not significant. Accordingly, in the base year, the suitable habitat for a high level of Acer pictum subsp. mono is 3.41% of the area of Korea, and in the near future (2011 - 2040) and far future (2071 - 2100), SSP1-2.6 accounts for 0.01% and 0.02%, gradually decreasing. However, in SSP5-8.5, it was 0.01% and 0.72%, respectively, showing a tendency to decrease in the near future compared to the base year, but to gradually increase toward the far future. This study confirms the future distribution of vegetation that is more easily adapted to climate change, and has significance as a basic study that can be used for future forest restoration of climate change-adapted species.

Seeking for a Curriculum of Dance Department in the University in the Age of the 4th Industrial Revolution (4차 산업혁명시대 대학무용학과 커리큘럼의 방향모색)

  • Baek, Hyun-Soon;Yoo, Ji-Young
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.3
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    • pp.193-202
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    • 2019
  • This study focuses on what changes are required as to a curriculum of dance department in the university in the age of the 4th industrial revolution. By comparing and analyzing the curricula of dance department in the five universities in Seoul, five academic subjects as to curricula of dance department, which covers what to learn for dance education in the age of the 4th industrial revolution, are presented. First, dance integrative education, the integration of creativity and science education, can be referred to as a subject that stimulates ideas and creativity and raises artistic sensitivity based on STEAM. Second, the curriculum characterized by prediction of the future prospect through Big Data can be utilized well in dealing with dance performance, career path of dance-majoring people, and job creation by analyzing public opinion, evaluation, and feelings. Third, video education. Seeing the images as modern major media tends to occupy most of the expressive area of art, dance by dint of video enables existing dance work to be created as new form of art, expanding dance boundaries in academic and performing art viewpoint. Fourth, VR and AR are essential techniques in the era of smart media. Whether upcoming dance studies are in the form of performance or education or industry, for VR and AR to be digitally applied into every relevant field, keeping with the time, learning about VR and AR is indispensable. Last, the 4th industrial revolution and the curriculum of dance art are needed to foresee the changes in the 4th industrial revolution and to educate changes, development and seeking in dance curriculum.

Landscape Object Classification and Attribute Information System for Standardizing Landscape BIM Library (조경 BIM 라이브러리 표준화를 위한 조경객체 및 속성정보 분류체계)

  • Kim, Bok-Young
    • Journal of the Korean Institute of Landscape Architecture
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    • v.51 no.2
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    • pp.103-119
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    • 2023
  • Since the Korean government has decided to apply the policy of BIM (Building Information Modeling) to the entire construction industry, it has experienced a positive trend in adoption and utilization. BIM can reduce workloads by building model objects into libraries that conform to standards and enable consistent quality, data integrity, and compatibility. In the domestic architecture, civil engineering, and the overseas landscape architecture sectors, many BIM library standardization studies have been conducted, and guidelines have been established based on them. Currently, basic research and attempts to introduce BIM are being made in Korean landscape architecture field, but the diffusion has been delayed due to difficulties in application. This can be addressed by enhancing the efficiency of BIM work using standardized libraries. Therefore, this study aims to provide a starting point for discussions and present a classification system for objects and attribute information that can be referred to when creating landscape libraries in practice. The standardization of landscape BIM library was explored from two directions: object classification and attribute information items. First, the Korean construction information classification system, product inventory classification system, landscape design and construction standards, and BIM object classification of the NLA (Norwegian Association of Landscape Architects) were referred to classify landscape objects. As a result, the objects were divided into 12 subcategories, including 'trees', 'shrubs', 'ground cover and others', 'outdoor installation', 'outdoor lighting facility', 'stairs and ramp', 'outdoor wall', 'outdoor structure', 'pavement', 'curb', 'irrigation', and 'drainage' under five major categories: 'landscape plant', 'landscape facility', 'landscape structure', 'landscape pavement', and 'irrigation and drainage'. Next, the attribute information for the objects was extracted and structured. To do this, the common attribute information items of the KBIMS (Korean BIM Standard) were included, and the object attribute information items that vary according to the type of objects were included by referring to the PDT (Product Data Template) of the LI (UK Landscape Institute). As a result, the common attributes included information on 'identification', 'distribution', 'classification', and 'manufacture and supply' information, while the object attributes included information on 'naming', 'specifications', 'installation or construction', 'performance', 'sustainability', and 'operations and maintenance'. The significance of this study lies in establishing the foundation for the introduction of landscape BIM through the standardization of library objects, which will enhance the efficiency of modeling tasks and improve the data consistency of BIM models across various disciplines in the construction industry.

Characteristics and Implications of 4th Industrial Revolution Technology Innovation in the Service Industry (서비스 산업의 4차 산업혁명 기술 혁신 특성과 시사점)

  • Pyoung Yol Jang
    • Journal of Service Research and Studies
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    • v.13 no.2
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    • pp.114-129
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    • 2023
  • In the era of the 4th industrial revolution, the importance of the 4th industrial revolution technology is increasing in the service industry. The purpose of this study is to identify the development and utilization status of the 4th industrial revolution technology in the service industry and to derive the characteristics and implications of the 4th industrial revolution technology innovation in the service industry. In this study, research and analysis were conducted based on the business activity survey data in order to identify the technological innovation characteristics of the 4th industrial revolution in the service industry. The 4th industrial revolution technology in the service industry was analyzed in terms of company ratio, technology development and utilization rate, development/utilization technology, technology application field, and technology development method. In addition, the trend of the 4th industrial revolution technology change in the service industry was also analyzed. The 4th industrial revolution technology utilization and development status of other industries was compared and analyzed. In particular, the service industry 4th industrial revolution technology innovation type was divided into 4 types from the perspective of the 4th industrial revolution company ratio and the 4th industrial revolution company ratio growth rate, and types for each service industry were derived. The characteristics and implications of the 4th industrial revolution technology innovation in the service industry were presented from nine perspectives. As a result of the study, it was found that companies in the service industry were developing or using 4th industrial revolution technologies more actively than companies in other industries, and it was analyzed that the gap was further widening. By service industry, information and communication, finance and insurance, and educational service showed relatively high rates of developing or utilizing 4th industrial revolution technologies. The service industries in which the share of 4th industrial revolution companies increased the most were real estate, education service, health and social welfare service. In particular, cloud, big data, and artificial intelligence were analyzed as the three core technologies of the fourth industrial revolution. The service industry can be classified into 4 types in terms of the 4th industrial revolution company ratio and growth rate, and service industry innovation measures that reflect the differentiated innovation characteristics of each type are needed.

Mitigation of Insufficient Capacity Problems of Central Bus Stops by Controlling Effective Green Time (유효녹색시간 조정을 활용한 중앙버스정류장 용량 부족 완화 방안 연구)

  • Koo, Kyo Min;Lee, Jae Duk;Ahn, Se Young;Chang, Iljoon
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.21 no.1
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    • pp.35-50
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    • 2022
  • After the introduction of the central bus lane system, bus traffic was prioritized. This resulted in improved trust from bus users. However, the low capacity at the central bus stop reduces traffic speed and punctuality. In addition, physical constraints are inevitable because the construction of central bus lanes and bus stops considers the city's road geometry. Therefore, this study attempted to optimize the effective green time of the traffic signal system at the entrance and exit of the central bus stop to remedy its insufficient operational capacity. The Transit Capacity and Quality of Service Manual and Korea Highway Capacity Manual were used as the analysis methodologies. The number of stop areas for central bus stops to be built was determined by excluding variable physical factors, and field survey data collected from nine randomly selected central bus stops currently installed in Seoul were used. A scenario analysis was conducted on the central bus stops with insufficient capacity by adjusting the effective green time, and the capacity of the central bus stop was set as the dependent variable. According to the results, 26.7 percent of the central bus stops with insufficient capacity can solve the problem of insufficient capacity. Therefore, the results of this study can be verified by improving the operation level, and it can be effective even if the number of central bus stops calculated by engineering is not guaranteed during the planning stage of the central bus stop. As the number of central bus stops is expected to increase further as the number of central bus stops increases, it is necessary to improve the number of central bus stops. Therefore, it is hoped that the results presented in this study will be used as basic data for the improvement plan at the operational level before introducing the physical improvement plan.

Overview of Utilization of Four-wheel Tractor in Korea(I) -Ownership and Annual Use by Different Farm Groups- (농용(農用)트랙터 이용(利用)에 관(關)한 조사연구(調査硏究)(I) -경영형태별(經營形態別) 농작업이용실태분석(農作業利用實態分析)-)

  • Park, Ho Seok;Kim, Kyong Su;Lee, Yong Kook;Han, Sung Kum
    • Journal of Biosystems Engineering
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    • v.6 no.2
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    • pp.20-32
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    • 1982
  • This survey was conducted to investigate the present status of farm tractor utilization for obtaining a basic reference to the establishment of the government's agricultural mechanization strategies. Thirty two counties from the eight provinces except Jeju were covered in this study. From these selected areas, 433 sample farms having farm tractor were taken to obtain the general informations by the enquete, and 93 sample farms among them to investigate the status of daily tractor use in the year of 1980. The analyzed results are summarized as follows: 1. Farm tractors owned by the rice-oriented farms holds 71.5 percent of the total number of tractors the livestock-oriented farms 17.0 percent, and the orchard-oriented farms 7.0 percent. Among the farm tractors 64.3 percent was a large size (46ps) and 35.7 percent a small size(19~23ps). 2. Most of the tractors surveyed were equipped with the essential attachments such as plow and rotavator. About 18 percent of the tractor owners had no trailer, which seemed too high considering the large percentage of tractor use for transportation. The availability of other attachments was very low except a grader on the rice-oriented farms and a hay harvester and a front loader on the livestock-oriented farms. 3. The average size of farm was 3.9 hectare for the rice-oriented farms, 13.9 hectare for the livestock-oriented farms and 7.4 hectare for the orchard-oriented farms. It was obious that the average farm size of was too small compared to the theoretical machine capacity of the tractors. 4. About 70 percent of the tractor operators were in the age of twenties and thirties. About 90 percent of them had an educational level of middle school graduate or above even though their technical level was very low. 5. Any particular problem in tractor use was not found in this survey. From the farmer's preference for purchasing a new tractor, however, it is estimated the demand on a 20-30ps tractor will be more increased. 6. The average annual use of tractor was of about 100 days or 400 hours. It appeared that the rice-oriented farms used most with 412.4 hours per year, and followed by the livestock-oriented farms with 403.6 hours, the orchard oriented farms with 377.7 hours. 7. Among the total hours of tractor use, 47.3 percent was for transportation, and 41.6 percent was for plowing and rotary tillage. The largest portion of the annual tractor use was taken by transportation on the livestock-oriented farms, by land preperation on the rice-oriented farms, and by loading and chemical spraying on the orchard-oriented farms. 8. The hours of tractor use had a peak in May. The hours of use for own farm was remarkably different among the different farm oriented, but there was no considerable difference between the too different sizes of tractor. 9. The hours of tractor use decreased as the age of the operator or the educational level increased. The reason might be that the operators who had a high educational level or were older had a tendency of disliking custom works. 10. The average custom use of tractor was 171.3 hours per year, and the ratio of custom work was 63.7 percent on the rice-oriented farms, 31.7 percent on the livestock-oriented farms and 22.4 percent on the orchard-oriented farms. Among the custom works, the most popular one was the grader leveling. 11. The charge on custom work was about 40,000 Won per hectare for plowing and rotary tillage, and it was the most expensive in the southeastern region, and next followed by the southwestern region. 12. The average plowing capacity of the small tractor was 7.8 hours per hectare in the paddy field, and that of the large tractors was 4.3 hours per hectare. The average rotary-tilling capacities of the small and the large tractors were 6.5 and 4.3 hours per hectare, in the paddy field respectively.

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