• Title/Summary/Keyword: Protective solution

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The Self-Fault Determination and Restoration Methodology based on the Ethernet Communication (이더넷 통신기반의 자율적 고장 판단 및 복구 방법론 연구)

  • Ko, Yun-Seok;Lee, Seo-Han;Choi, Hyun-Chul;Shin, Jae-Hyun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.9
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    • pp.1674-1680
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    • 2009
  • This paper proposes an autonomous fault determination, fault zone isolation and fault restoration strategy based on the ethernet communication as a new attempt to solve the problem the of the existing central control method. In proposed method, The FRTU(Feeder Remote Terminal Unit)s on the feeder determines autonomously where the faulted zone is by exchanging the voltage and current information with neighbor FRTUs based on the network communication, and then separates the faulted zone in an nil-voltage status to make the protective device to reclose successively. In particular, the minimization of outage time and relational load balancing is archived by each interconnection switch which determines autonomously the load zone to be allocated among those zones after the sound outage zones was separated individually. Finally, to show effectiveness of the proposed fault restoration strategy, the several fault cases are simulated for the test distribution system, and the load balancing index of the proposed solution is compared with all of feasible solutions.

A Study on Detection of High Impedance Fault in Low Voltage DC Distribution System using Filter based on Mathematical Morphology (수학적 형태학 기반의 필터를 이용한 저압직류 배전계통의 고저항 지락고장 검출에 관한 연구)

  • Oh, Yun-Sik;Noh, Chul-Ho;Kim, Doo-Ung;Gwon, Gi-Hyeon;Han, Joon;Kim, Chul-Hwan
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.29 no.11
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    • pp.89-95
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    • 2015
  • As a solution of improving the energy efficiency in power system, Low Voltage DC (LVDC) distribution systems different from conventional ones have been constantly researched. As in conventional AC distribution system, LVDC distribution system can suffer from High Impedance Fault (HIF) which may cause a failure of protective relay due to relatively low change in magnitude of fault current. In order to solve the problem, a scheme for detecting HIFs is presented in this paper. Closing Opening Difference Operation (CODO) based on Mathematical Morphology (MM), one of the MM-based filters, is utilized to make fault signals discriminable. To verify performance of the scheme, a simple LVDC distribution system is modeled by using ElectroMagnetic Transient Program (EMTP) software. Computer simulations according to various conditions are performed and comparison studies with a scheme using Wavelet Transform (WT) in an aspect of simulation time are also conducted.

The Biocompatibility of HA Film Deposition on Anodized Titanium Alloy

  • Lee, Kang;Choe, Han-Choel;Kim, Byung-Hoon;Ko, Yeong-Mu
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.10a
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    • pp.213-214
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    • 2009
  • A thin film hydroxyapatite (HA) films was deposited on anodized titanium by RF sputtering method. The anodized titanium enhanced the biocompatibility of the Ti and the bioactivity was improved further by the HA deposited on the anodized Ti. $TiO_2$ layer with $0.2{\sim}0.5{\mu}$ diameter pore size was formed on the Ti surface by anodization. Anodized $TiO_2$ layer analysis HA film deposited, oxide pore size and number decreased compared with non-HA deposited surface. The corrosion resistance of HA deposited/anodized Ti was higher than that of the non-treatment Ti alloy in Hank's solution, indicating better protective effect. From the results of cell culture using MTT assays, the best cell proliferation showed in HA deposited surface after anodization of Ti surfaces compared with another surface treatment.

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Anti-inflammatory Activity of Sambucus Plant Bioactive Compounds against TNF-α and TRAIL as Solution to Overcome Inflammation Associated Diseases: The Insight from Bioinformatics Study

  • Putra, Wira Eka;Salma, Wa Ode;Rifa'i, Muhaimin
    • Natural Product Sciences
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    • v.25 no.3
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    • pp.215-221
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    • 2019
  • Inflammation is the crucial biological process of immune system which acts as body's defense and protective response against the injuries or infection. However, the systemic inflammation devotes the adverse effects such as multiple inflammation associated diseases. One of the best ways to treat this entity is by blocking the tumor necrosis factor alpha ($TNF-{\alpha}$) and TNF-related apoptosis-inducing ligand (TRAIL) to avoid the proinflammation cytokines production. Thus, this study aims to evaluate the potency of Sambucus bioactive compounds as anti-inflammation through in silico approach. In order to assess that, molecular docking was performed to evaluate the interaction properties between the $TNF-{\alpha}$ or TRAIL with the ligands. The 2D structure of ligands were retrieved online via PubChem and the 3D protein modeling was done by using SWISS Model. The prediction results of the study showed that caffeic acid (-6.4 kcal/mol) and homovanillic acid (-6.6 kcal/mol) have the greatest binding affinity against the $TNF-{\alpha}$ and TRAIL respectively. This evidence suggests that caffeic acid and homovanillic acid may potent as anti-inflammatory agent against the inflammation associated diseases. Finally, this study needs further examination and evaluation to validate the potency of Sambucus bioactive compounds.

Features of Administrative Liability for Offenses in the Informational Sphere

  • Iasechko, Svitlana;Kuryliuk, Yurii;Nikiforenko, Volodymyr;Mota, Andrii;Demchyk, Nadiia;Berizko, Volodymyr
    • International Journal of Computer Science & Network Security
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    • v.21 no.8
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    • pp.51-54
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    • 2021
  • The article is devoted to the study of the features of administrative liability for offenses in the informational sphere, the definition of the concept and features. Based on the examples of implementation of instruments of European legislation into the national legal system and examples of national legal practice, the authors have identified the features of informational and legal sanctions aimed at restricting the rights of access of subjects to information, prohibiting them to disseminate certain information, restricting the rights to disseminate certain information, and suspending informational activities. It has been substantiated that the administrative liability for informational offenses as a protective legal institution is created to contribute to the solution of such acute problems of legal support of human and society interests in the new informational dimensions.

Immunosecurity: immunomodulants enhance immune responses in chickens

  • Yu, Keesun;Choi, Inhwan;Yun, Cheol-Heui
    • Animal Bioscience
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    • v.34 no.3_spc
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    • pp.321-337
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    • 2021
  • The global population has increased with swift urbanization in developing countries, and it is likely to result in a high demand for animal-derived protein-rich foods. Animal farming has been constantly affected by various stressful conditions, which can be categorized into physical, environmental, nutritional, and biological factors. Such conditions could be exacerbated by banning on the use of antibiotics as a growth promoter together with a pandemic situation including, but not limited to, African swine fever, avian influenza, and foot-and-mouth disease. To alleviate these pervasive tension, various immunomodulants have been suggested as alternatives for antibiotics. Various studies have investigated how stressors (i.e., imbalanced nutrition, dysbiosis, and disease) could negatively affect nutritional physiology in chickens. Importantly, the immune system is critical for host protective activity against pathogens, but at the same time excessive immune responses negatively affect its productivity. Yet, comprehensive review articles addressing the impact of such stress factors on the immune system of chickens are scarce. In this review, we categorize these stressors and their effects on the immune system of chickens and attempt to provide immunomodulants which can be a solution to the aforementioned problems facing the chicken industry.

Corrosion Protection Effectiveness and Adsorption Performance of Schiff Base-Quinazoline on Mild Steel in HCl Environment

  • Sayyid, Firas F.;Mustafa, Ali M.;Hanoon, Mahdi M.;Shaker, Lina M.;Alamiery, Ahmed A.
    • Corrosion Science and Technology
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    • v.21 no.2
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    • pp.77-88
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    • 2022
  • Schiff base quinazoline derivative viz., 3-((2-hydroxy-3-methoxybenzylidene)amino)-2-methylquinazolin-4(3H)-one (SB-Q), was synthesized in this study. Its corrosion protection impact on mild steel (MS) in 1 M hydrochloric acid solution was examined by performing weight loss measurements. The protective efficacy of SB-Q on MS in 1 M HCl was investigated based on its concentrations, immersion period, and immersion temperature. SB-Q was found to be an efficient inhibitor for the corrosion of MS. Its inhibition efficiency was improved by increasing the concentration of SB-Q to an optimal concentration of 500 ppm. Its inhibition efficacy was 96.3% at 303K. Experimental findings revealed that its inhibition efficiency was increased with increasing immersion time, but decreased with an increase in temperature. The adsorption of SB-Q molecules was followed the Langmuir adsorption isotherm model. The adsorption of the examined inhibitor molecules on the surface of mild steel was studied by density functional theory (DFT). DFT investigation confirmed weight loss findings.

Mathematical modeling of the local temperature effect on the deformation of the heat-shielding elements of the aircraft

  • Antufiev, Boris A.;Sun, Ying;Egorova, Olga V.;Bugaev, Nikolay M.
    • Advances in aircraft and spacecraft science
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    • v.9 no.1
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    • pp.59-68
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    • 2022
  • The physical and mathematical foundations of the heat-shielding composite materials functioning under the conditions of aerodynamic heating of aircraft, as well as under the conditions of the point effect of high-energy radiation are considered. The problem of deformation of a thin shallow shell under the action of a local temperature field is approximately solved. Such problems arise, for example, in the case of local destruction of heat-protective coatings of aircraft shells. Then the aerodynamic heating acts directly on the load-bearing shell of the structure. Its destruction inevitably leads to the death of the entire aircraft. A methodology has been developed for the numerical solution of the entire complex problem on the basis of economical absolutely stable numerical methods. Multiple results of numerical simulation of the thermal state of the locally heated shallow shell under conditions of its thermal destruction at high temperatures have been obtained.

Probabilistic service life of box culvert due to carbonation of concrete cover

  • Woo, Sang-Kyun;Chu, In-Yeop;Lee, Yun;Lee, Byung-Jae
    • Advances in concrete construction
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    • v.12 no.6
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    • pp.517-525
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    • 2021
  • More underground structures are increasingly being constructed such as box culverts for electric power transmission, and the life extension of these structures is very important. It is well known that the steel embedded in concrete is usually invulnerable to corrosion because the high alkalinity of the pore solution in concrete generates a thin protective oxide layer on the surface of the steel. Recent observations in the field and experimental evidence have shown that even steel in concrete can be corroded through the carbonation reaction of cover concrete. Carbonation-induced corrosion in concrete may often occur in a high carbon dioxide environment. In this study, the risk of carbonation of underground box culverts in Korea was evaluated by measuring the car¬bonation rate and concrete cover depth in the field. Then, the carbonation-free service life for the cover depth of the steel was calcu¬lated with in situ information and Monte Carlo simulation. Additionally, an accelerated carbonation test for a cracked beam specimen was performed, and the effect of a crack on the service life of a box culvert was numerically investigated with Monte Carlo simulation based on experimental results.

Use of Capparis decidua Extract as a Green Inhibitor for Pure Aluminum Corrosion in Acidic Media

  • Al-Bataineh, Nezar;Al-Qudah, Mahmoud A.;Abu-Orabi, Sultan;Bataineh, Tareq;Hamaideh, Rasha S.;Al-Momani, Idrees F.;Hijazi, Ahmed K.
    • Corrosion Science and Technology
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    • v.21 no.1
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    • pp.9-20
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    • 2022
  • The aim of this paper is to study corrosion inhibition of Aluminum with Capparis decidua extract. The study was performed in a 1.0 M solution of hydrochloric acid (HCl) and was monitored both by measuring mass loss and by using electrochemical and polarization methods. A scanning electron microscopy (SEM) technique was also applied for surface morphology analysis. The results revealed high inhibition efficiency of Capparis decidua extract. Our data also determined that efficiency is governed by temperature and concentration of extract. Optimum (88.2%) inhibitor efficiency was found with maximum extract concentration at 45 o C. The results also showed a slight diminution of aluminum dissolution when the temperature is low. Based on the Langmuir adsorption model, Capparis decidua adsorption on the aluminum surface shows a high regression coefficient value. From the results, the activation enthalpy (∆H#) and activation entropy (∆S#) were estimated and discussed. In conclusion, the study clearly shows that Capparis decidua extract acted against aluminum corrosion in acidic media by forming a protective film on top of the aluminum surface.