• Title/Summary/Keyword: 공학전공

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Evaluation of antioxidant activity, zebrafish embryo toxicity, and regenerative efficacy of Symphoricarpos albus (Symphoricarpos albus의 항산화능과 Zebrafish 배아 독성 및 재생 효능 평가)

  • Chanwoo Lee;HyeYeon Heo;Myunsoo Kim;YoungPyo Jang;Bo Ae Kim
    • Journal of the Korean Applied Science and Technology
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    • v.41 no.2
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    • pp.292-304
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    • 2024
  • This study compared and evaluated the antioxidant activities of Symphoricarpos albus(S. albus) extract and fermented extract. Antioxidant activity was measured by DPPH radical scavenging, FRAP, and ABTS. Concentrations were measured at 200, 100, 50, and 10 ㎍/mL, and antioxidant activity increased in a concentration-dependent manner. S. albus leaves fermented extracts had the highest antioxidant activity. And this study evaluated the safety and tail regeneration of S. albus extract using zebrafish model embryos. Zebrafish are in the spotlight as an alternative animal and can be used for cosmetic research. Zebrafish embryos were collected and evaluated for coagulation rate, hatching rate, and cardiotoxicity. As a result, it was toxic at concentrations above 100 ㎍/ml. The tail was cut and the regenerative effect was observed for 3 days. As a result, from 72 hours, S. albus 200ug/ml leaf extract showed a 17% regenerative effect compared to the control group. These results suggest that S. albus can be used as a natural material for antioxidant and regeneration for skin improvement.

A Study on Productivity and Efficiency Comparative Analysis of Container Terminal (국내 항만배후단지 효율성 및 생산성 비교 분석)

  • Min-Seop Sim;Do-Yeon Ha;Yul-Seong Kim
    • Journal of Navigation and Port Research
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    • v.48 no.1
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    • pp.17-26
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    • 2024
  • Port distripark can activate more functions. It is adjacent to a port. However, domestic port distripark is still limited to support port because of the shortage of infrastructure facilities, government policy, and investment. Therefore, this study tried to investigate the operation status of domestic port distripark and derive policy implications by conducting DEA analysis and productivity analysis based on internal data of each port distripark. As a result of Data Envelopment analysis, it was found that the west port distripark of Gwangwang and the northern port distripark of Incheon were efficient in the warehouse industry while the northern port distripark of Incheon and the Ulsan 1 port distripark were efficient in the manufacturing industry. In addition, in the case of foreign investment productivity, the west side port distripark of Gwangyang and the stage 1 port distripark of Pyeongtaek Dangjin were found to be higher than the others. In the case of facility investment productivity, the port distripark on the west side of Gwangyang and the north side of Incheon had the highest productivity. Lastly, in the case of labor productivity, the north side of Incheon and Busan ungdong port distripark showed the highest productivity. These results imply that it is important to review handling item when picking up enterprises in the port distripark for enhancing efficiency, foreign investment, and facility investment. The number of employees is not directly affecting the productivity improvement.

Literary Research Using Digital Analysis Tools: A Case Study of 『Dangerous Liaisons』 ('디지털 분석 도구를 활용한 문학 연구 : 라클로의 『위험한 관계Les liaisons dangereuses』를 중심으로)

  • RYU Sun-Jung;YOU Eun-Soon
    • The Journal of the Convergence on Culture Technology
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    • v.10 no.3
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    • pp.173-180
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    • 2024
  • We This study aimed to quantitatively analyze the theme of 'libertinage' and the associated issues of reason and emotion in 『Dangerous Liaisons』, a novel considered a masterpiece of libertine literature and an epistolary novel of the 18th century, using digital analysis tools. First, based on the frequency analysis of word usage using Voyant and LIWC 22, we confirmed that libertinage is manifested with keywords such as 'love' and 'time'. With Voyant's 'Contexts' feature, it was found that the letters sent by Valmont to Madame de Tourvel and those sent by Madame de Merteuil both have 'love' as the central theme. However, emotional vocabulary was higher in the former, whereas strategic vocabulary was more prevalent in the latter. Additionally, it was observed that the most frequently used word in the letters sent by Madame de Merteuil is 'time', with a higher frequency than 'love'. Thirdly, using LIWC 22, we measured the analytical thinking and emotional tone of the letters exchanged by the main characters, and analyzed how these values changed according to the chapters. Through these analyses, we confirmed that this novel, alongside Rousseau's "New Eloise," anticipates romanticism by embracing the theme of 'emotion,' which was rejected by 18th-century Enlightenment ideals.

Development of hydro-mechanical-damage coupled model for low to intermediate radioactive waste disposal concrete silos (방사성폐기물 처분 사일로의 손상연동 수리-역학 복합거동 해석모델 개발)

  • Ji-Won Kim;Chang-Ho Hong;Jin-Seop Kim;Sinhang Kang
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.26 no.3
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    • pp.191-208
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    • 2024
  • In this study, a hydro-mechanical-damage coupled analysis model was developed to evaluate the structural safety of radioactive waste disposal structures. The Mazars damage model, widely used to model the fracture behavior of brittle materials such as rocks or concrete, was coupled with conventional hydro-mechanical analysis and the developed model was verified via theoretical solutions from literature. To derive the numerical input values for damage-coupled analysis, uniaxial compressive strength and Brazilian tensile strength tests were performed on concrete samples made using the mix ratio of the disposal concrete silo cured under dry and saturated conditions. The input factors derived from the laboratory-scale experiments were applied to a two-dimensional finite element model of the concrete silos at the Wolseong Nuclear Environmental Management Center in Gyeongju and numerical analysis was conducted to analyze the effects of damage consideration, analysis technique, and waste loading conditions. The hydro-mechanical-damage coupled model developed in this study will be applied to the long-term behavior and stability analysis of deep geological repositories for high-level radioactive waste disposal.

Spatial Distribution Pattern of Cladoceran Community in Accordance with Microhabitat Types (미소서식처 유형별 지각류 (Cladocerans)의 분포 특성)

  • Jong-Yun Choi
    • Korean Journal of Environment and Ecology
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    • v.38 no.3
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    • pp.324-337
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    • 2024
  • Aquatic macrophytes are important factors in determining species diversity and abundance of cladocerans, but the effects of cladocerans on plant species composition or structure have not been fully considered. In South Korea, wetlands and reservoirs that are prone to covering aquatic macrophytes are scattered across the country, so it is necessary to consider on aquatic macrophytes study, when aquatic animals including cladoceran were studied. in this study, the species and abundance of cladocerans community in six microhabitat types are investigated, and based on these results, habitat conservation and efficient management are suggested. The high species numbers and abundance of cladocerans communities were found in mixed plant communities consisting of free-floating, floating-leaved, and submerged plants. The inclusion of submerged plants in plant communities contributes significantly to the complexity of habitat structures, and may increase species and abundance of cladocenran communities. This can be compared to a plant community consisting only of free-floating and floating-leaved plants in the absence of submerged plants, thereby identifying the efficiency of submerged plants. In the mixed plant communities, species diversity was the highest due to the emergence of cladoceran species (Graptoleveris testudinaria, Ilyocryptus spinifer, and Leydigia acanthococcides) absent from other plant communities. The gradual increase in the biomass (g) of submerged plants in the mixed plant communities significantly increased the species numbers and abundance of cladoceran communities (p<0.05). This is strong evidence that the increase of submerged plants in mixed plant communities has a positive effect on efficiency as a habitat for cladocerans. Although submeged plants do not contribute significantly to their landscape/aesthetic value because they are submerged in water, they have the effect of increasing species diversity in terms of biology, so they should be considered important when creating/restoring wetlands.

Comparative Analysis on Network Slicing Techniques in 5G Environment (5G 환경에서의 네트워크 슬라이싱 연구 비교 분석)

  • A Reum Ko;Ilhwan Ji;Hojun Jin;Seungho Jeon;Jung Taek Seo
    • Journal of Platform Technology
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    • v.11 no.5
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    • pp.84-96
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    • 2023
  • Network slicing refers to a technology that divides network infrastructure into multiple parts. Network slicing enables flexible network configuration while minimizing the physical resources required for network division. For this reason, network slicing technology has recently been developed and introduced in a form suitable for the 5G environment for efficient management of large-scale network environments. However, systematic analysis of network slicing research in the 5G environment has not been conducted, resulting in a lack of systematic analysis of the technology. Accordingly, in this paper, we provide insight into network slicing technology in the 5G network environment by conducting a comparative analysis of the technology. In this study's comparative analysis, 13 literatures on network slicing in the 5G environment was identified and compared and analyzed through a systematic procedure. As a result of the analysis, three network slicing technologies frequently used for 5G networks were identified: RAN (radio access network) slicing, CN (core network) slicing, and E2E (end-to-end) sliding. These technologies are mainly used for network services. It was confirmed that research is being conducted to achieve quality improvement and network isolation. It is believed that the results of this comparative analysis study can contribute to 6G technology research as a future direction and utilization plan for network slicing research.

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Study on Method to Develop Case-based Security Threat Scenario for Cybersecurity Training in ICS Environment (ICS 환경에서의 사이버보안 훈련을 위한 사례 기반 보안 위협 시나리오 개발 방법론 연구)

  • GyuHyun Jeon;Kwangsoo Kim;Jaesik Kang;Seungwoon Lee;Jung Taek Seo
    • Journal of Platform Technology
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    • v.12 no.1
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    • pp.91-105
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    • 2024
  • As the number of cases of applying IT systems to the existing isolated ICS (Industrial Control System) network environment continues to increase, security threats in the ICS environment have rapidly increased. Security threat scenarios help to design security strategies in cybersecurity training, including analysis, prediction, and response to cyberattacks. For successful cybersecurity training, research is needed to develop valid and reliable security threat scenarios for meaningful training. Therefore, this paper proposes a case-based security threat scenario development methodology for cybersecurity training in the ICS environment. To this end, we develop a methodology consisting of five steps based on analyzing actual cybersecurity incident cases targeting ICS. Threat techniques are standardized in the same form using objective data based on the MITER ATT&CK framework, and then a list of CVEs and CWEs corresponding to the threat technique is identified. Additionally, it analyzes and identifies vulnerable functions in programming used in CWE and ICS assets. Based on the data generated up to the previous stage, develop security threat scenarios for cybersecurity training for new ICS. As a result of verification through a comparative analysis between the proposed methodology and existing research confirmed that the proposed method was more effective than the existing method regarding scenario validity, appropriateness of evidence, and development of various scenarios.

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A Study on the Improvement of Port Security Function in Busan Port - Target of Port facility security costs collection - (부산항 항만보안 기능 개선 연구 -항만시설보안료 징수대상을 중심으로-)

  • Kim, Seong-Hwan;Lee, Jeong-Min;Kim, Yul-Seong
    • Journal of Korea Port Economic Association
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    • v.39 no.4
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    • pp.127-145
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    • 2023
  • As the importance of strengthening port security is increasing, it is necessary to conduct a perceptual study on port facility users who pay for port security services first. This study aims to identify improvements in the port security function of Busan Port and contribute to the future development of port security in Korea. A total of 125 questionnaires were collected from port facility security fee collectors at Busan Port. Based on the collected data, exploratory factor analysis, traditional IPA, and modified IPA were conducted. In conclusion, first, the physical function of port security is the most important and should be continuously maintained and strengthened. Second, improving the professionalism of port security personnel is most urgent, and the port security education system needs to be improved. Finally, it is necessary to gradually develop the port security information service function in consideration of future development possibilities.

Breeding of new variety Pleurotus pulmonarius using protoplast fusion technique (원형질체융합 기법을 이용한 산느타리 계통육성)

  • Gwon, Hee-Min;Lee, Yun-Hae;Kim, Jeong-Han;Baek, Il-Sun;Kang, Hee-Wan;Choi, Jong-In
    • Journal of Mushroom
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    • v.19 no.3
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    • pp.166-175
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    • 2021
  • In this study, monokaryons of "Heukari" (Pleurotus ostreatus) and "Hosan" (Pleurotus pulmonarius) were separated to remove the cell wall, and a cross-species protoplast fusion was developed through chemical treatment with polyethylene glycol. The protoplast-fused PF160306 and PF160313 strains have a culture period of 10 and 2 days shorter than that of the "Heuktari" and "Hosan" cultivars, respectively. Furthermore, the growth of the strains was faster than that of the existing cultivars. The yield was 135.9 g per bottle, which was approximately 8% higher than that of the commercially available "Hosan" cultivar; however, it was not statistically significant. A growth survey was conducted after treatment at five temperatures (15, 18, 21, 23, and 25℃). The growth of the strains accelerated with the increase in temperature. However, at 21℃, the yellow color of pileus was the brightest. Band pattern, assessed using URP Primer 7, was similar to that of the "Hosan" cultivar. The DPPH radical scavenging capacity and polyphenol content were 62.5% and 43.5 mg/mL, respectively, for "Sunjung" and 65.7% and 49.9 mg/mL, respectively, for PF160313. Furthermore, the antihypertensive activities of the "Sunjung" cultivar and PF160313 were similarly high at 74% and 75%, respectively. In conclusion, cross-species hybridization via the protoplast fusion technique can be used for obtaining primary data for mushroom breeding to develop new varieties. In addition, the protoplast fusion technique might aid in expanding the market for yellow mushrooms.

Assessment of Fire-Damaged Mortar using Color image Analysis (색도 이미지 분석을 이용한 화재 피해 모르타르의 손상 평가)

  • Park, Kwang-Min;Lee, Byung-Do;Yoo, Sung-Hun;Ham, Nam-Hyuk;Roh, Young-Sook
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.3
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    • pp.83-91
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    • 2019
  • The purpose of this study is to assess a fire-damaged concrete structure using a digital camera and image processing software. To simulate it, mortar and paste samples of W/C=0.5(general strength) and 0.3(high strength) were put into an electric furnace and simulated from $100^{\circ}C$ to $1000^{\circ}C$. Here, the paste was processed into a powder to measure CIELAB chromaticity, and the samples were taken with a digital camera. The RGB chromaticity was measured by color intensity analyzer software. As a result, the residual compressive strength of W/C=0.5 and 0.3 was 87.2 % and 86.7 % at the heating temperature of $400^{\circ}C$. However there was a sudden decrease in strength at the temperature above $500^{\circ}C$, while the residual compressive strength of W/C=0.5 and 0.3 was 55.2 % and 51.9 % of residual strength. At the temperature $700^{\circ}C$ or higher, W/C=0.5 and W/C=0.3 show 26.3% and 27.8% of residual strength, so that the durability of the structure could not be secured. The results of $L^*a^*b$ color analysis show that $b^*$ increases rapidly after $700^{\circ}C$. It is analyzed that the intensity of yellow becomes strong after $700^{\circ}C$. Further, the RGB analysis found that the histogram kurtosis and frequency of Red and Green increases after $700^{\circ}C$. It is analyzed that number of Red and Green pixels are increased. Therefore, it is deemed possible to estimate the degree of damage by checking the change in yellow($b^*$ or R+G) when analyzing the chromaticity of the fire-damaged concrete structures.