• Title/Summary/Keyword: Barrier

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Bibliometric Analysis of Herbal Medicine on Atopic Treatment Research Trends over the Past 20 Years (최근 20년간 한약을 중심으로 한 아토피 질환 치료에 대한 계량서지학적 분석)

  • Hye-Jin Park;Hyoen-Jun Cheon;So-Eun Son;So-Mi Jung;Jeong-Hwa Choi;Soo-Yeon Park;Min-Yeong Jung;Jong-Han Kim
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.36 no.2
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    • pp.60-75
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    • 2023
  • Objectives : A bibliometric approach using network analysis was applied to explore the global trends of research on herbal medicine for atopic treatment. Methods : Articles related to herbal medicine on atopic treatment from 2003 to 2022 were retrieved from Web of Science Core Collection. Extracted records were analyzed according to the publication year, research area, journal title, country, organization, author and keyword. The VOSviewer program was used to visualize the trends and the research hotspots in herbal medicine for atopy. Results : Analysis of 406 articles indicated the consistent increase of using herbal medicine for atopic treatment over the last 20 years. The most productive country and research organization in issuing articles were South Korea and Kyunghee university. Many articles have been published in research areas such as 'integrative complementary medicine' and 'pharmacology pharmacy'. By evaluating the total link strength, the average publication year and the average citations of countries and authors, the influential countries and authors were identified. A network analysis based on the co-occurrence and the publication year of keywords revealed the relevant characteristics and trends of herbal medicine for atopy. The most up-to-date keywords were 'topical application', 'skin barrier' and 'care'. Conclusions : This bibliometric study examined the overall trends and the time-based development of herbal medicine for atopic treatment. The current study would be useful not only for grasping the global network hub of research on herbal medicine for atopic treatment, but also to explore the new directions for future research.

Introduction of Two-region Model for Simulating Long-Term Erosion of Bentonite Buffer (벤토나이트 완충재 장기 침식을 모사하기 위한 Two-region 모델 소개)

  • Jaewon Lee;Jung-Woo Kim
    • Tunnel and Underground Space
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    • v.33 no.4
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    • pp.228-243
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    • 2023
  • Bentonite is widely recognized and utilized as a buffer material in high-level radioactive waste repositories, mainly due to its favorable characteristics such as swelling capability and low permeability. Bentonite buffers play an important role in ensuring the safe disposal of radioactive waste by providing a low permeability barrier and effectively preventing the migration of radionuclides into the surrounding rock. However, the long-term performance of bentonite buffers still remains a subject of ongoing research, and one of the main concerns is the erosion of the buffer induced by swelling and groundwater flow. The erosion of the bentonite buffer can significantly impact repository safety by compromising the integrity of buffer and leading to the formation of colloids that may facilitate the transport of radionuclides through groundwater, consequently elevating the risk of radionuclide migration. Therefore, it is very important to numerically quantify the erosion of bentonite buffer to evaluate the long-term performance of bentonite buffer, which is crucial for the safety assessment of high-level radioactive waste disposal. In this technical note, Two-region model is introduced, a proposed model to simulate the erosion behavior of bentonite based on a dynamic bentonite diffusion model, and quantitative evaluation is conducted for the bentonite buffer erosion with this model.

Evaluation of thermal-hydro-mechanical behavior of bentonite buffer under heating-hydration condition at disposal hole (처분공 가열-수화 조건에서 벤토나이트 완충재의 열-수리-역학적 거동 특성 평가)

  • Yohan Cha;Changsoo Lee;Jin-Seop Kim;Minhyeong Lee
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.25 no.2
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    • pp.175-186
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    • 2023
  • The buffer materials in disposal hole are exposed to the decay heat from spent nuclear fuels and groundwater inflow through adjacent rockmass. Since understanding of thermal-hydro-mechanical-chemical (T-H-M-C) interaction in buffer material is crucial for predicting their long-term performance and safety of disposal repository, it is necessary to investigate the heating-hydration characteristics and consequent T-H-M-C behavior of the buffer materials under disposal conditions considering geochemical factors. In response, the Korea Atomic Energy Research Institute developed a laboratory-scale 'Lab.THMC' experiment system, which characterizes the T-H-M behavior of buffer materials under different geochemical conditions by analyzing heating-hydration process and stress changes. This technical report introduces the detail design of the Lab.THMC system, summarizes preliminary experimental results, and outlines future research plans.

Sustained release of alginate hydrogel containing antimicrobial peptide Chol-37(F34-R) in vitro and its effect on wound healing in murine model of Pseudomonas aeruginosa infection

  • Shuaibing Shi;Hefan Dong;Xiaoyou Chen;Siqi Xu;Yue Song;Meiting Li;Zhiling Yan ;Xiaoli Wang ;Mingfu Niu ;Min Zhang;Chengshui Liao
    • Journal of Veterinary Science
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    • v.24 no.3
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    • pp.44.1-44.17
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    • 2023
  • Background: Antibiotic resistance is a significant public health concern around the globe. Antimicrobial peptides exhibit broad-spectrum and efficient antibacterial activity with an added advantage of low drug resistance. The higher water content and 3D network structure of the hydrogels are beneficial for maintaining antimicrobial peptide activity and help to prevent degradation. The antimicrobial peptide released from hydrogels also hasten the local wound healing by promoting epithelial tissue regeneration and granulation tissue formation. Objective: This study aimed at developing sodium alginate based hydrogel loaded with a novel antimicrobial peptide Chol-37(F34-R) and to investigate the characteristics in vitro and in vivo as an alternative antibacterial wound dressing to treat infectious wounds. Methods: Hydrogels were developed and optimized by varying the concentrations of crosslinkers and subjected to various characterization tests like cross-sectional morphology, swelling index, percent water contents, water retention ratio, drug release and antibacterial activity in vitro, and Pseudomonas aeruginosa infected wound mice model in vivo. Results: The results indicated that the hydrogel C proved superior in terms of cross-sectional morphology having uniformly sized interconnected pores, a good swelling index, with the capacity to retain a higher quantity of water. Furthermore, the optimized hydrogel has been found to exert a significant antimicrobial activity against bacteria and was also found to prevent bacterial infiltration into the wound site due to forming an impermeable barrier between the wound bed and external environment. The optimized hydrogel was found to significantly hasten skin regeneration in animal models when compared to other treatments in addition to strong inhibitory effect on the release of pro-inflammatory cytokines (interleukin-1β and tumor necrosis factor-α). Conclusions: Our results suggest that sodium alginate -based hydrogels loaded with Chol-37(F34-R) hold the potential to be used as an alternative to conventional antibiotics in treating infectious skin wounds.

High-efficiency deep geological repository system for spent nuclear fuel in Korea with optimized decay heat in a disposal canister and increased thermal limit of bentonite

  • Jongyoul Lee;Kwangil Kim;Inyoung Kim;Heejae Ju;Jongtae Jeong;Changsoo Lee;Jung-Woo Kim;Dongkeun Cho
    • Nuclear Engineering and Technology
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    • v.55 no.4
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    • pp.1540-1554
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    • 2023
  • To use nuclear energy sustainably, spent nuclear fuel, classified as high-level radioactive waste and inevitably discharged after electricity generation by nuclear power plants, must be managed safely and isolated from the human environment. In Korea, the land area is limited and the amount of high-level radioactive waste, including spent nuclear fuels to be disposed, is relatively large. Thus, it is particularly necessary to maximize disposal efficiency. In this study, a high-efficiency deep geological repository concept was developed to enhance disposal efficiency. To this end, design strategies and requirements for a high-efficiency deep geological repository system were established, and engineered barrier modules with a disposal canister for pressurized water reactor (PWR)-type and pressurized heavy water reactor type Canada deuterium uranium (CANDU) plants were developed. Thermal and structural stability assessments were conducted for the repository system; it was confirmed that the system was suitable for the established strategies and requirements. In addition, the results of the nuclear safety assessment showed that the radiological safety of the new system met the Korean safety standards for disposal of high-level radioactive waste in terms of radiological dose. To evaluate disposal efficiency in terms of the disposal area, the layout of the developed disposal areas was assessed in terms of thermal limits. The estimated disposal areas were 2.51 km2 and 1.82 km2 (existing repository system: 4.57 km2) and the excavated host rock volumes were 2.7 Mm3 and 2.0 Mm3 (existing repository system: 4.5 Mm3) for thermal limits of 100 ℃ and 130 ℃, respectively. These results indicated that the area and the excavated volume of the new repository system were reduced by 40-60% compared to the existing repository system. In addition, methods to further improve the efficiency were derived for the disposal area for deep geological disposal of spent nuclear fuel. The results of this study are expected to be useful in establishing a national high-level radioactive waste management policy, and for the design of a commercial deep geological repository system for spent nuclear fuels.

Categorization of UX method based on UX expert's competence model (UX 전문가의 역량 모델에 기반한 수행역량유사도에 따른 UX 방법론 분류에 대한 연구)

  • Lee, Ahreum;Kang, Hyo Jin;Kwon, Gyu Hyun
    • Design Convergence Study
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    • v.16 no.4
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    • pp.1-16
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    • 2017
  • As the local manufacturing industry has entered a phase of stagnation, service and product design based on user experience has been highlighted as an alternative for the innovation. However, SMEs(Small and Medium-sized Enterprises) are still struggling to overcome the current crisis. One of the reasons is that SMEs do not have enough contact points with the validated UX firms and experts. Thus, SMEs has a high barrier to invest in new opportunity area, user experience. In this study, we aim to figure out UX experts' competence to perform the UX method to solve the UX problems based on the KSA framework(Knowledge, Skill, Attitude). Based on the literature review and expert workshop, we grouped the UX method according to the similarity of the competence required to conduct the method. With cluster analysis, 5 different groups of UX method were defined based on the competence, Panoramic Analysis, Meticulous Observation and Analysis, Intuitive Interpretation, Agile Visualization, and Logical Inspection. The results would be applied to compose a portfolio of UX experts and to implement a mechanism that could recommend the professional experts to the company.

Method for Cultivating the Technology Transfer Based on Extracting the Technology Transfer Broker -Case Study of Global MVP (기술이전중개자 도출을 통한 기술이전 활성화 방법론 -Global MVP 연구단 사례)

  • Chun, Ha Sung;Kim, Sang Duck;Hong, Jong-yi
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.6 no.7
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    • pp.361-370
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    • 2016
  • Effective acquisition technology is an important factor determining the competitiveness of companies(Roxas et al., 2011). Since the importance of technology transfer has been increased, there has been a growing interest in company, government, university and research institutes (Bozeman et al., 2015). Despite the national efforts for activating technology transfer, a lot of technology is still in universities and R&D center(Ockwell et al., 2009). The barriers of technology transfer are a main reason to inhibit the technology transfer. In order to be lower technology transfer barriers, it is necessary to derive the technology transfer broker based on social network analysis. However, most studies related to technology transfer broker had been focused on empirical study(Bozeman et al., 2015). Therefore, it is needed to suggest the method to grasp the opportunity that can lead to technology innovation based on analyzing and visualizing the network of technology transfer. The method in this study provides the company with the connectable path, technology transfer broker and strategy to classify the technology actor within the network. Finally, the method is applied to Global MVP for verifying the feasibility of method.

Effects of Dielectric Curing Temperature and T/H Treatment on the Interfacial Adhesion Energies of Ti/PBO for Cu RDL Applications of FOWLP (FOWLP Cu 재배선 적용을 위한 절연층 경화 온도 및 고온/고습 처리가 Ti/PBO 계면접착에너지에 미치는 영향)

  • Kirak Son;Gahui Kim;Young-Bae Park
    • Journal of the Microelectronics and Packaging Society
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    • v.30 no.2
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    • pp.52-59
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    • 2023
  • The effects of dielectric curing temperature and temperature/humidity treatment conditions on the interfacial adhesion energies between Ti diffusion barrier/polybenzoxazole (PBO) dielectric layers were systematically investigated for Cu redistribution layer applications of fan-out wafer level package. The initial interfacial adhesion energies were 16.63, 25.95, 16.58 J/m2 for PBO curing temperatures at 175, 200, and 225 ℃, respectively. X-ray photoelectron spectroscopy analysis showed that there exists a good correlation between the interfacial adhesion energy and the C-O peak area fractions at PBO delaminated surfaces. And the interfacial adhesion energies of samples cured at 200 ℃ decreased to 3.99 J/m2 after 500 h at 85 ℃/85 % relative humidity, possibly due to the weak boundary layer formation inside PBO near Ti/PBO interface.

Proficiency testing of cadmium and lead in polypropylene resin (폴리프로필렌 수지 중 카드뮴과 납 측정 숙련도시험)

  • Cho, K.H.;Lim, M.C.;Min, H.S.;Han, M.S.;Song, H.J.;Park, C.J.
    • Analytical Science and Technology
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    • v.20 no.3
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    • pp.183-192
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    • 2007
  • The various environmental regulation directives such as RoHS (restriction of hazardous substances in electrical and electronic products) and WEEE (waste from electrical and electronic equipments) are practically used as the technical barrier in international trade (TBT) of vehicles and electrical and electronic products recently. Regarding such an environmental regulation, Korea Research Institute of Standards Science (KRISS) organized a proficiency testing scheme to establish the reliability of measurement results produced by the relevant research institutes and test laboratories in Korea. Participants were 31 laboratories related to production of the electrical and electronic equipments and mobile vehicles. Two polypropylene samples of pellet type were employed as the proficiency testing materials (PTMs). Cadmium and lead were the analytes chosen among six components regulated in European Union (EU) RoHS directive. The PTMs were sent to the participants by post on September $1^{st}$ 2006, and deadline for results submission were October $10^{th}$ 2006. The results of each laboratory were evaluated in comparison with KRISS reference values using Robustic Z-score and Youden plot methods. The results of the various sample digestion methods were also compared. Most of participants reported good agreement within 10 % range of reference values. However, results from several laboratories showed significant biases from reference values. These laboratories should establish the quality assurance system for improvement of the measurement reliability.

Properties on the Strength of Polymer Concrete Using Nano MMT-UP Composite (나노 MMT-폴리머 복합체를 이용한 폴리머 콘크리트의 강도 특성)

  • Jo, Byung-Wan;Moon, Rin-Gon;Park, Seung-Kook
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4A
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    • pp.761-766
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    • 2006
  • Polymer composite are increasingly considered as structural components for use in civil engineering, on account of their enhanced strength-to-weight ratios. Unsaturated polyester (UP) resin have been widely used for the matrix of composites such as FRP and polymer composite, due to its excellent adhesive. Polymer nanocomposites are new class of composites derived from the nano scale inorganic particles with dimensions typically in the range of 1 to 1000 nm that are dispersed in the polymer matrix homogeneously. Owing to the high aspect ratio of the fillers, mechanical, thermal, flame, retardant and barrier properties are enhanced without significant loss of clarity, toughness or impact strength. To prepare the MMT (Montmorillonite)-UP exfoliated nanocomposites, UP was mixed with MMT at $60^{\circ}C$ for 3 hours by using pan mixer. XRD (X-ray diffraction) pattern of the composites and TEM (Transmission Electron Micrographs) showed that the interlayer spacing of the modified MMT were exfoliated in polymer matrix. The mechanical properties also supported these findings, since in general, tensile strength, modulus with modified MMT were higher than those of the composites with unmodified MMT. The thermal stability of MMT-UP nanocomposite is better than that of pure UP, and its glass transition temperature is higher than that of pure UP. The polymer concrete made with MMT-UP nanocomposite has better mechanical properties than of pure UP. Therefore, it is suggested that strength and elastic modulus of polymer concrete was found to be positively tensile strength and tensile modulus of the MMT-UP nanocomposites.