• Title/Summary/Keyword: Distribution Protection

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A Study on the Automation of MVDC System-Linked Digital Substation (MVDC 시스템연계 디지털변전소 자동화 연구)

  • Jang, Soon Ho;Koo, Ja Ik;Mun, Cho Rong
    • KIPS Transactions on Computer and Communication Systems
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    • v.10 no.7
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    • pp.199-204
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    • 2021
  • Digital substation refers to a substation that digitizes functions and communication methods of power facilities such as monitoring, measuring, control, protection, and operation based on IEC 61850, an international standard for the purpose of intelligent power grids. Based on the intelligent operating system, efficient monitoring and control of power facilities is possible, and automatic recovery function and remote control are possible in the event of an accident, enabling rapid power failure recovery. With the development of digital technology and the expansion of the introduction of eco-friendly renewable energy and electric vehicles, the spread of direct current distribution systems is expected to expand. MVDC is a system that utilizes direct current lines with voltage levels and transmission capacities between HVDCs applied to conventional transmission systems and LVDCs from consumers. Converting existing lines in substations, where most power equipment is alternating current centric, to direct current lines will reduce transmission losses and ensure greater current capacity. The process bus of a digital substation is a communication network consisting of communication equipment such as Ethernet switches that connect installed devices between bay level and process level. For MVDC linkage to existing digital substations, the process level was divided into two buses: AC and DC, and a system that can be comprehensively managed in conjunction with diagnostic IEDs as well as surveillance and control was proposed.

Genomic Polymorphism Analysis Using Microsatellites in the Jeju Dogs (제주개의 microsatellite 마커를 이용한 유전적 다양성 분석)

  • Ko, Minjeong;Kwon, Seulgi;Kim, Hye-Ran;Byun, Jae-Hyun;Kim, Dae-Cheol;Choi, Bong-Hwan
    • Journal of Life Science
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    • v.29 no.6
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    • pp.637-644
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    • 2019
  • This study was conducted to analyze the genetic characteristics of the Jeju dog for preservation and protection. A total of 139 dogs from 7 dog breeds, including the Jeju dog, were genotyped using 16 microsatellite markers. The results revealed 2-18 alleles per locus, with a total of 131 alleles among the 16 markers. Most alleles were identified for FH3381, which had 18 alleles, whereas FH2834 had the fewest alleles, with just 2. When the total mean value was observed, the expected heterozygosity and observed heterozygosity were higher for than for outgroup dogs, and the PIC values ranged from 0.000 to 0.862, respectively. The phylogenetic tree analysis of the Jeju dog and other dog varieties revealed that the Jeju dog is closest to the Sapsal dog (0.393). The phylogeny between the Jeju and Korean domestic dogs showed that the Jeju dog is most distant from the Dongkyung dog (0.507). Looking at the distribution individually, the Jeju dog is in the same group as the Labrador Retriever and the Sapsal dog. Meanwhile, the Poongsan, Dongkyung, and Jindo dogs and the German Shepherd were in the same group. Genetic information confirmed through the results of this study can be used as basic data to study the genetic characteristics of the Jeju dog.

A Comparative Study on the Effects of Pinellia ternata, Zingiber officinale and Sobanhatang on Reflux Esophagitis (역류성 식도염에 대한 반하(半夏), 생강(生薑), 소반하탕(小半夏湯)의 효과 비교)

  • Lee, Seul-hee;Baik, Tai-Hyeun
    • The Journal of Korean Medicine
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    • v.40 no.2
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    • pp.17-34
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    • 2019
  • Objectives: This study was carried out to observe and compare the effects of Pinellia ternata, Zingiber officinale and Sobanhatang on the reflux esophagitis induced by gastric fundus and pylorus ligation in mice with esomeprazole. Methods: Antioxidant effects were measured by DPPH radical scavenging activity at four different concentration of 0.125, 0.25, 0.5 and $1.0mg/102{\mu}{\ell}$. Zingiber officinale water extract(ZE), Pinellia ternata water extract(PE) and Sobanhatang water extract(SBE) and esomeprazole were treated orally for 14 days before gatric fundus and pylorus ligation. In the histochemistry, changes in suface mucous cells, muscle tissue and connective tissue in gastro esophageal junction(GEJ) and mast cell on the esophageal mucosa were observed. The change of Hemo oxygenase(HO)-1, ghrelin, gastrin and substance P in gastric body tissue were measured by immunohistochemistry. Results: DPPH radical scavenging activity exhibited concentration dependently increases in ZE, PE, SBE. ZE was significantly higher at all concentrations than PE. The gastric surface mucous cells were more in the treated group than in the reflux esophagitis elicited group(GE) in the order of PE, SBE, ZE and esomeprazole treateded group(PT, SBT, ZT, ET). Lower esophageal sphincter muscle damage and intercellular space in the GEJ were less in the treated group than GE. In the esophageal mucosa, the mast cell distribution and the migration of inflammatory cells were lower in the treateded troup than GE in order to ZT, SBT, PT and ET. The antioxidative enzyme, HO-1 was more in the order of ZT, SBT, control group, PT, ET than in GE. ZT was significantly higher than the other groups and SBT was significantly higher than ET. Ghrelin was found to be higher in ZT, ET, SBT and PT than in GE, and ZT was significantly higher than all other groups except ET. Gastrin showed the highest positivity in GE, and was lower in the order of ET, ZT, SBT, PT, and control group. Substance P was the highest in GE, and was lower in the order of ET, ZT, SBT, PT and control group, and PT were significantly lower than ET. Conclusion: ZT, PT and SBT showed superior antioxidative, anti-inflammatory and mucosal protective effects on mouse reflux esophagitis as compared with ET. In particular, ZE was more effective in antioxidant and gastric motility enhancement, while PE was more effective in mucosal protection and anti-inflammatory effects. Sobanhatang is expected to be effective treatment because it has advantages of both drugs and reduces toxicity.

Gintonin-mediated release of astrocytic vascular endothelial growth factor protects cortical astrocytes from hypoxia-induced cell damages

  • Choi, Sun-Hye;Kim, Hyeon-Joong;Cho, Hee-Jung;Park, Sang-Deuk;Lee, Na-Eun;Hwang, Sung-Hee;Rhim, Hyewon;Kim, Hyoung-Chun;Cho, Ik-Hyun;Nah, Seung-Yeol
    • Journal of Ginseng Research
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    • v.43 no.2
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    • pp.305-311
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    • 2019
  • Background: Gintonin is a ginseng-derived exogenous ligand of the G protein-coupled lysophosphatidic acid (LPA) receptor. We previously reported that gintonin stimulates gliotransmitter release in primary cortical astrocytes. Astrocytes play key roles in the functions of neurovascular systems. Although vascular endothelial growth factor (VEGF) is known to influence the normal growth and maintenance of cranial blood vessels and the nervous system, there is little information about the effect of gintonin on VEGF regulation in primary astrocytes, under normal and hypoxic conditions. Methods: Using primary cortical astrocytes of mice, the effects of gintonin on the release, expression, and distribution of VEGF were examined. We further investigated whether the gintonin-mediated VEGF release protects astrocytes from hypoxia. Results: Gintonin administration stimulated the release and expression of VEGF from astrocytes in a concentration- and time-dependent manner. The gintonin-mediated increase in the release of VEGF was inhibited by the LPA1/3 receptor antagonist, Ki16425; phospholipase C inhibitor, U73122; inositol 1,4,5- triphosphate receptor antagonist, 2-APB; and intracellular $Ca^{2+}$ chelator, BAPTA. Hypoxia further stimulated astrocytic VEGF release. Gintonin treatment stimulated additional VEGF release and restored cell viability that had decreased due to hypoxia, via the VEGF receptor pathway. Altogether, the regulation of VEGF release and expression and astrocytic protection mediated by gintonin under hypoxia are achieved via the LPA receptor-VEGF signaling pathways. Conclusion: The present study shows that the gintonin-mediated regulation of VEGF in cortical astrocytes might be neuroprotective against hypoxic insults and could explain the molecular basis of the beneficial effects of ginseng on the central nervous system.

A Comparative Study on HSI and MaxEnt Habitat Prediction Models: About Prionailurus bengalensis (HSI와 MaxEnt를 통한 삵의 서식지 예측 모델 비교 연구)

  • Yoo, Da-Young;Lim, Tai-Yang;Kim, Whee-Moon;Song, Won-Kyong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.24 no.5
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    • pp.1-14
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    • 2021
  • Excessive development and urbanization have destroyed animal, plant, habitats and reduced biodiversity. In order to preserve species diversity, habitat prediction studies are have been conducted at home and overseas using various modeling techniques. This study was conducted to suggest optimal habitat modeling research by comparing HSI and MaxEnt, which are widely used among habitat modeling techniques. The study was targeted on the endangered species of Prionailurus bengalensis in nearby areas (5460.35km2) including Cheonan City, and the same data were used for analysis to compare those models. According to the HSI analysis, Prionailurus bengalensis's habitat probability was 74.65% for less than 0.5 and 25.34% for more than 0.5 and the top 30% were forest (99.07%). MaxEnt's analysis showed that 56.22% of those below 0.5 and 43.79% of those above 0.5 were found to have a high explanatory power of 78.3% of AUC. The Paired Wilcoxn test, which evaluated the significance of thoes models, confirmed that the mean difference between the two models was statistically significant (p<0.05). Analysis of the differences in the results of those models using the matrix table shows that score 24.43% HSI and MaxEnt was accordance,12.44% of the 0.0 to 0.2 section, 7.22% of the 0.2 to 0.4 section, 2.73% of the 0.4 to 0.6 section, 1.96% of the 0.6 to 0.8, and 0.08% of the 0.9 to 1.0. To verify where the score difference appears, the result values of those models were reset to values from 1 to 5 and overlaid. Overlapping analysis resulted in 30.26% of the Strongly agree values, 56.77% of the agree values, and 11.92% of the Disagree values. The places where the difference in scores occurs were analyzed in the order of forest (45.23%), agricultural land (34.57%), and urbanization area (7.65%). This confirmed that the analysis of the same target species within the same target site also has differences in forecasts depending on the modelling method. Therefore, a novel analysis method combining the advantages of each modeling in habitat prediction studies should be developed, and future study may be used to select Prionailurus bengalensis and species-protected areas and species protection areas in the future. Further research is judged to require higher accuracy studies through the use of various modeling techniques and on-site verification.

Analysis of Minimum Detectable Activity Concentration of Water Samples and Evaluation of Effective Dose (물 시료의 최소검출가능 농도 분석과 유효선량 평가)

  • Jang, Eun-sung;Kim, Yang-su;Lee, Sun-young;Kim, Jung-Soo
    • Journal of the Korean Society of Radiology
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    • v.14 no.7
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    • pp.857-862
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    • 2020
  • In March 2011, a tsunami off Japan caused radioactive material that had seeped into the sea from the Fukushima nuclear accident to flow to the Pacific Ocean, causing pollution to sea life. For a comparative evaluation with the area surrounding the site of a nuclear power plant by the release of radioactive materials, an area 20 to 30 km away from the emergency protection plan area was selected as a comparative point considering weather conditions, population distribution, etc. In addition, the government intends to analyze the minimum detection radiation received by residents around the nuclear power plant and evaluate the effective dose. Analysis of tritium radiation from water samples showed that most of the samples were not detected and that 0.0014 % to 0.777 % of the annual legal standard of 1 mSv for the general public had little effect on the human body. Therefore, the measurement and analysis of water samples around the nuclear power plant site is expected to help relieve anxiety, such as exposure to the general public and neighboring residents due to radiation release.

Extending the OMA DRM Framework for Supporting an Active Content (능동형 콘텐츠 지원을 위한 OMA DRM 프레임워크의 확장)

  • Kim, Hoo-Jong;Jung, Eun-Su;Lim, Jae-Bong
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.16 no.5
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    • pp.93-106
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    • 2006
  • With the rapid growth of the wireless Internet communication, a new generation of mobile devices have made possible the broad distribution of mobile digital contents, such as image, music, video, games and applications over the wireless Internet. Mobile devices are rapidly becoming the major means to extend communication channels without copy Protection, usage rule controlling and authentication. As a result, mobile digital contents may be illegally altered, copied and distributed among unauthorized mobile devices. In this paper, we take a look at Open Mobile Alliance (OMA) DRM v2.0 in general, its purpose and function. The OMA is uniquely the focal point for development of an open standard for mobile DRM. Next we introduces features for an active content and illustrates the difference between an active content and an inactive content. Enabling fast rendering of an active content, we propose an OMA-based DRM framework. This framework include the following: 1) Extending DCF Header for supporting an selective encryption, 2) Content encryption key management, 3) Rendering API for an active content. Experimental results show that the proposed framework is able to render an active content fast enough to satisfy Quality of Experience. %is framework has been proposed for a mobile device environment, but it is also applicable to other devices, such as portable media players, set-top boxes, or personal computer.

A Study on the Copyright Protection Liability of Online Service Provider and Filtering Measure (온라인서비스제공자(OSP)의 저작권보호 책임과 필터링)

  • Oh, Yeong-Woo;Jang, Gye-Hyun;Kwon, Hun-Yeong;Lim, Jong-In
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.20 no.6
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    • pp.97-109
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    • 2010
  • Although the primary liability for online copyright infringement may fall on the individual who illegally copies, transfers, and/or distributes the copyrighted content, the issue of indirect liability for Online Service Providers (OSPS) that provide a channel for the distribution of illegal content has recently come under the spotlight. Currently, in an effort to avoid liability for indirect copyright infringement and improve their reputation, most OSPs have voluntarily applied filtering technology. Under the Copyright Act of Korea, special types of OSPS including P2P and Web-based Hard Drive (WebHard) are required to incorporate filtering technology, and may be charged with penalties if found without one. However, despite the clear need for filtering mechanisms, several arguments have been set forth that question the efficacy and appropriateness of the system. As such, this paper discusses the liability theory adopted in the US. -a leader in internet technology development-and analyzes the scope of liability and filtering related regulations in our copyright law. In addition, this paper considers the current applications of filtering as well as limits of the applied filtering technology in OSPS today. Finally, we make four suggestions to improve filtering in Korea, addressing issues such as clarifying the limits and responsibilities of OSPS, searching for cooperative solutions between copyright holders and OSPS, standardizing the filtering technology to enable compatibility among different filtering techniques, and others.

Research on illegal copyright distributor tracking and profiling technology (불법저작물 유포자 행위분석 프로파일링 기술 연구)

  • Kim, Jin-gang;Hwang, Chan-woong;Lee, Tae-jin
    • Journal of Internet Computing and Services
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    • v.22 no.3
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    • pp.75-83
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    • 2021
  • With the development of the IT industry and the increase of cultural activities, the demand for works increases, and they can be used easily and conveniently in an online environment. Accordingly, copyright infringement is seriously occurring due to the ease of copying and distribution of works. Some special types of Online Service Providers (OSP) use filtering-based technology to protect copyrights, but they can easily bypass them, and there are limits to blocking all illegal works, making it increasingly difficult to protect copyrights. Recently, most of the distributors of illegal works are a certain minority, and profits are obtained by distributing illegal works through many OSP and majority ID. In this paper, we propose a profiling technique for heavy uploader, which is a major analysis target based on illegal works. Creates a feature containing information on overall illegal works and identifies major heavy uploader. Among these, clustering technology is used to identify heavy uploader that are presumed to be the same person. In addition, heavy uploaders with high priority can be analyzed through illegal work Distributor tracking and behavior analysis. In the future, it is expected that copyright damage will be minimized by identifying and blocking heavy uploader that distribute a large amount of illegal works.

Designation, Preservation, Management, and Utilization of National Prehistoric Sites (선사시대 사적의 지정·보존·관리 현황과 활용 방안)

  • HWANG, Jaehoon
    • Korean Journal of Heritage: History & Science
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    • v.55 no.2
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    • pp.232-249
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    • 2022
  • The purpose of this article is to review the status of designation and preservation, management of national prehistoric sites and to suggest future applications. Prior to the discussion, the overall status of national prehistoric sites was reviewed. Specifically, the current status of designation, designated area, and distribution by region of national prehistoric sites according to the period and nature of the sites were examined in detail. Next, in order to understand the preservation and management of national prehistoric sites, I report the results of field trips to several sites, such as Geomdan-ri in Ulju, Songguk-ri in Buyeo, and Seoktaek-ri in Hongseong, and propose some measures for preservation, maintenance, and management of the remains. Finally, by referring to cases of US national historic sites such as protection, conservation, operation and management system and academic research project of cultural heritage, it is necessary to consider the need for a direction of the utilization that considers both socio-economic aspects as well as education and research on cultural heritage. The active use of cultural heritage can be a measure that leads to the continuous preservation and management of the sites, and ultimately will be a shortcut to increasing the value of national prehistoric sites.