• Title/Summary/Keyword: Link Protection

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Module-Type Switching Rectifier for Cathodic Protection of Underground and Maritime Metallic Constructions (지하매설 및 해양 금속구조물 음극방식용 모듈 타입 스위칭 정류기)

  • Moon Sang-Ho;Kim Bo-Kyoung;Kim In-Dong;Nho Eui-Cheol;Kwon Young-Won;Jeong Seong-Woo;Lim Heon-Ho
    • Proceedings of the KIPE Conference
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    • 2002.07a
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    • pp.529-532
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    • 2002
  • 본 과제를 통해 금속 구조물 음극 방식용 고성능 스위칭 정류기를 개발하였다. 개발된 정류기 회로는 크게 두 부분, 즉 1대로 구성된 AC/DC 컨버터부와 4대로 구성된 Module Type DC/DC 컨버터부로 되어 있다. AC/DC 컨버터는 IGBT PWM Rectifier로서 입력전압의 역률을 거의 1로 제어하고 있으며 또한 DC Link 전압을 일정하게 제어하고 있다. Module Type DC/DC 컨버터는 ZCS/ZVS 스위칭 동작을 통하여 스위칭 손실 감소와 함께 고주파 동작을 가능하게 하여, 입력측과 출력측의 전기적 절연을 위한 변압기로 고주파 변압기를 사용할 수 있게 하였다. 이로 인해 시스템의 부피와 무게를 현저히 감소시켰다. 본 과제에서 개발한 방식용 정류기 기술은 다른 유사 분야에의 적용도 가능한 것으로 사료된다.

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A Study on the Development of System for Dispatcher (상황실 화재 접수자 중심의 화재상황별 시스템 개발 연구)

  • Choi, Doo-Chan;Ko, Min-Hyeok;Min, Se-Hong
    • Journal of the Society of Disaster Information
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    • v.16 no.1
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    • pp.203-209
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    • 2020
  • Purpose: This study aims to support the dispatcher to analysis the architecture type of fire. Method: Analysis the dispatch protocol guideline (released by gyunggi fire brigade) and make the dispatch scenario by site, combustibles, evacuation, fire extinguish systems. Result: After making scenario, develop the system (for dispatcher), is based on the tablet PC. Conclusion: Dispatch systems apply not only fire but rescue and disaster. This study focus on the fire, but It is need to expend the rescue and disaster. in korea, Fire Safety Evaluation and Multishop DB are possible to link to this system.

The Dynamic Modeling of Conflicting Issues in Public Organization : The System Simulation of Dynamic Interaction Between Environmental System and Regional Development System. (조직의 상충적 이슈에 관한 동태적 모델링 : 환경 시스템과 경제 시스템 간의 동태적 상호작용 분석과 시스템 시뮬레이션)

  • 홍민기
    • Korean System Dynamics Review
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    • v.1 no.1
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    • pp.159-183
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    • 2000
  • How to protect the environment without sacrificing the human environment and economy at the level of region is on of the most difficult issues of recent times. The dynamic Interactions between economic activities and environmental pollution control activities determine whether social welfare is increased of decreased by such activities and provides a basis for saying whether they help or hurt the economy. Bureaucratic Approach of Local government has failed, and an Impetus has arisen to develop new tools of analysis, useful for finding policy leverages focused on sustainability. This paper focus on understanding dynamic relationships between regional economic system and environmental system, and presenting possible framework for finding policy leverages in dynamic interaction behaviors. The case, selected in this study, is Nacdong river regions case, which is related many meaningful issues about sustainable development: two big metropolitan government and dwellers have different opinion with regard to construction of large scale Industrial pack, drinking water supply, and environment model consisting of three sectors: regional economy sector, river pollution and drinking water sector, environmental protection and investment policy sector Finally, this paper deal with how to link policy leverage to causal loop structure for the sustainable development of two regions.

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A Study on Information Security Governance Framework (정보보안 거버넌스 프레임워크에 관한 연구)

  • Kim, Min-Jun;Kim, Kui-Nam J.
    • Convergence Security Journal
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    • v.10 no.4
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    • pp.13-19
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    • 2010
  • The flow of time, depending on the company's ongoing business link to guarantee the proportion of much greater importance, it in the organization as part of an enterprise-wide level, rather than acting on the information society has been considered as the topic of race. Information Security Governance, the integrity of the information, service continuity, the three kinds of information asset protection purpose begins. It is essential for corporate governance, transparency should be part, must be aligned with the IT framework. Existing information security governance framework that small businesses a wide range of governance issues and interests have never had. Therefore, we simplified the information security governance framework is proposed, and solve problems, and propose a framework for analysis of the safety and efficiency through the analysis of the effectiveness of the proposed method were discussed.

Considering the scrambling code of the line Study on the New Korea joint protection Standard Hangul character (회선부호의 스크램블링을 고려한 새로운 한국표준 한글글자마디부호에 관한 연구)

  • Park, Yo-Seph;Hong, Wan-Pyo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.12
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    • pp.1345-1354
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    • 2015
  • This paper, information communication code standard($KS{\times}1001$, confirmation in 2004), as definded in Hangul Character Code Hangul AMI/HDB-3 the code set for the new system Hangul consonant and vowel tables presented. The result of the existing system and the code set ($4{\times}4$) bit source coding rules for comparing the frequency of use Hangul consonant and vowel tables(The National Institute of The Korea Language) and statistices showed that 44% of the data processing efficiency is improved.

TCP Congestion Control Algorithm using TimeStamp (TimeStamp를 이용한 TCP 혼잡제어 알고리즘)

  • 김노환
    • Journal of the Korea Society of Computer and Information
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    • v.5 no.3
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    • pp.126-131
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    • 2000
  • Through many users employ TCP of which the performance has been proved in Internet, but many papers Proposed to improve TCP performance according to varying network architecture. In Particular, BWDP(bandwidth-delay Product) grew larger because of the increasing delay in satellite link and the network's speed-up. To consider these increased bandwidth-delay product, it is suggested that TCP options include Window Scale option. TimeStamp option, and PAWS. Because TCP window size should be commonly high in the network with these increased bandwidth-delay product, the multiple decrease and linear increase scheme of current TCP would cause underflow and instability within network. Then TCP performance is reduced as a result. Thus, to improve TCP congestion control algorithm in the network which has large sized window, this paper proposes the congestion control scheme that controls window size by using TimeStamp option.

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Data-Linking Infrastructure for the Health Technology Assessment (의료기술평가 기반으로서의 데이터 연계)

  • Park, Chong Yon
    • The Journal of Health Technology Assessment
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    • v.6 no.2
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    • pp.81-87
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    • 2018
  • With the recent change of healthcare environment including rapid technological development, evidences are more and more important and necessary to support relevant policies in health technology assessment to provide safe and effective health services, utilizing medical resources efficiently. Despite of the emphasis on the importance of real world data and real world evidence in health care research, current infrastructure supporting clinical research is considerably weak due to absence of legal and institutional basis. However, in accordance with the Article 26 of the Health and Medical Technology Promotion Act, there is a limited legal apparatus that can be used only in public data with other dataset for the purpose of healthcare technology assessment at the National Evidence-based Collaborating Agency. Although the use of linked data from various sources was often required in the field of clinical research, it was not yet working well due to insufficient environmental conditions. In order to support the decision-making of medical practice and health care policies, data-linking platform for clinical research is needed. If the legal system that can link up to the data of the private institutions without violating the significant value such as the protection of private informations is established, it will be a decisive foundation reinforcing the researches and policy making processes for the improvement of the national health care system.

Security Threats and Attacks in Internet of Things (IOTs)

  • Almtrafi, Sara Mutlaq;Alkhudadi, Bdour Abduallatif;Sami, Gofran;Alhakami, Wajdi
    • International Journal of Computer Science & Network Security
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    • v.21 no.1
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    • pp.107-118
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    • 2021
  • The term Internet of Things (IoTs) refers to the future where things are known daily through the Internet, whether in one way or another, as it is done by the method of collecting various information from various sensors to form a huge network through which people, things and machines are helped to make a link between them at all time and anywhere. The IoTs is everywhere around us such as connected appliances, smart homes security systems and wearable health monitors. However, the question is what if there is a malfunction or outside interference that affects the work of these IoTs based devises? This is the reason of the spread of security causes great concern with the widespread availability of the Internet and Internet devices that are subject to many attacks. Since there aren't many studies that combines requirements, mechanisms, and the attacks of the IoTs, this paper which explores recent published studies between 2017 and 2020 considering different security approaches of protection related to the authentication, integrity, availability and confidentiality Additionally, the paper addresses the different types of attacks in IoTs. We have also addressed the different approaches aim to prevention mechanisms according to several researchers' conclusions and recommendations.

Characteristics of Environmental Solar Ultraviolet Irradiance

  • Sasaki, Masako;Oyanagi, Takehiko;Takeshita, Shu
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.154-157
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    • 2002
  • Direct, continuous, and accurate measurements of solar ultraviolet irradiance (290-400 nm: UVR) have been carried out since 1990, by using both band-spectral ultraviolet-B (290-320 nm: UV-B) and ultraviolet-A (320-400 nm: UV-A) radiometers at Tokai University in Hiratsuka, Japan (35$^{\circ}$N, 139$^{\circ}$E). From our observations, the following findings are provided: 1) an increasing trend in solar UV -B from Oct. 1990 to Sept. 2000; 2) a regional comparison of solar UVR in Japan; 3) the distinct characteristics of UV-B and UV-A irradiance, such as diffuse property, daily and seasonal variation; and 4) human body protection against solar UVR. An increasing 10-year trend in global solar UV - B in Hiratsuka corresponded to a decrease in the total ozone amount measured at Tsukuba (36$^{\circ}$N, 140$^{\circ}$E), giving supportive evidence for a direct link between these two parameters. Furthermore, a strong correlation was found between solar UV-B and total ozone amount from results of UVR measurements at four Tokai University monitoring stations dispersed throughout Japan. Additional results revealed different diffuse properties in global solar UV and in global solar total (300-3000 nm: Total) irradiances. For example, in the global UVR, the diffuse component was dominant: about 80 % independent of weather, with more than 60 % of global UV-B, and more than 50% of global UV-A with even a cloudless clear sky. On the other hand, the portion of the diffuse in the global total irradiance was very low, less than 10 % on a cloudless clear day. Daily and seasonal variations of UV -B and UV -A irradiances were found to be quite different, because of the marked dependence of UV -B irradiance on the atmospheric ozone amount. Moreover, UV -B irradiance showed large daily and seasonal variations: the ratio between maximum and minimum irradiances was more than 5. In contrast, the variation in UV-A was small: the ratio between maximum and minimum was less than 2. Three important facts are proposed concerning solar UVR protection of the human body: 1) the personal minimal erythema dose (MED); 2) gender based difference in MED values; and 3) proper colors for UVR protective clothing.

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Adaptation of p-Cycle considering QoS Constraints in WDM Networks (WDM 망에서 QoS 제약 조건을 고려한 p-Cycle 적용 방안)

  • Shin, Sang-Heon;Shin, Hae-Joon;Kim, Young-Tak
    • Journal of KIISE:Information Networking
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    • v.30 no.5
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    • pp.668-675
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    • 2003
  • In this paper, we propose an enhanced p-cycle (preconfigured protection cycle) scheme for WDM mesh networks with QoS constraints. In the previous researches on p-cycle, it is assumed that user's connection has a hi-directional connectivity and the same bandwidth on both direction. Therefore it is difficult to apply p-cycle based link protection to uni-directional connections for multicasting or asymmetric broadband multimedia communications with hi-directional connectivity. And it didn't consider QoS of backup path. We enhanced the p-cycles to accomodate uni-directional connections for multicasting or asymmetric bandwidth communications with hi-directional connectivity. And we propose a selection procedure of p-cycle to assure QoS of backup path. We were able to reduce a required backup bandwidth by applying a uni-directional p-cycle concept to asymmetric broadband multimedia communication environment. The proposed p-cycle selection procedure is applied to the U.S. sample network to evaluate whether the configured p-cycles can support QoS constraint of working path and backup path.