• Title/Summary/Keyword: protected zone

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Seismic Surface Wave Cloaking by Acoustic Wave Refraction (음향파 굴절을 이용한 지진파의 표면파 가림)

  • Lee, Dong-Woo;Kang, Young-Hoon;Kim, Sang-Hoon
    • Journal of the Earthquake Engineering Society of Korea
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    • v.19 no.6
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    • pp.257-263
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    • 2015
  • Recently two seismic cloaking methods of earthquake engineering have been suggested. One is the seismic wave deflection method that makes the seismic wave bend away and the other is the shadow zone method that makes an area that seismic waves cannot pass through. It is called as seismic cloaking. The fundamental principles of the seismic cloaking by variable refractive index were explained. A two-dimensional cylindrical model which was composed of 40 layers of different density and modulus was tested by numerical simulation. The center region of the model to be protected is called 'cloaked area' and the outer region of it to deflect the incoming wave is called 'cloaking area' or 'cloak area.' As the incoming surface wave is approaching to the cloaking area, the refractive index is decreasing and, therefore, the velocity and impedance are increasing. Then, the wave bends away the cloaked area instead of passing it. Three cases are tested depending on the comparison between the seismic wavelength and the diameter of the cloaked region. The advantage and disadvantage of the method were compared with conventional earthquake engineering method. Some practical requirements for realization in fields were discussed.

The Industrial Security along with the International Transfer of Technology (국제기술이전계약에서의 산업보안에 관한 연구)

  • SEO, Jung-Doo
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.76
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    • pp.1-20
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    • 2017
  • The industrial technology (including trade secrets), which is commonly understood as systematic and applied technical knowledge, can be transferred to third parties by contracting for the transfer of technology or by granting of a licence. The activity of industrial espionage, due to the gradual increase of the economic interests of intellectual property, is displaying intensively in order to gain advanced technology information. With our outstanding high technology, but compared to the level of the advanced countries, the technical protection systems, the legal protection measures and the systematic management thereof may still be insufficient. Our industrial technology outflow abroad, due to the vulnerability to the security control system in our country, has been increasing since the 2000. Computer software and SNS, such as smart devices, appear as a rapid change in the technical information environment. In order to minimize the dead zone of a new industrial security, the country's organic activity is being conducted. In 2006, Industrial Technology Outflow Prevention and Protection Law was enacted, which emphasized the responsibilities of the country. In this paper for the economic entity's efforts to prevent technology leakage oversea, I have looked to how the industrial technology can be protected in terms of national security and economic benefits of our enterprises. To solve the above-mentioned problems hereof, Korean government should willingly establish a reliable legal system for supporting to enterprise's operations, and Korean companies should autonomously introduce a synthetic technology protection system and incorporate the confidentiality clauses in an international transfer of technology agreement with third parties.

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Evaluation of seismic criteria of built-up special concentrically braced frames

  • Izadi, Amin;Aghakouchak, Ali A.
    • Steel and Composite Structures
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    • v.29 no.1
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    • pp.23-37
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    • 2018
  • In this paper, seismic provisions related to built-up special concentrically braced frames (BSCBFs) are investigated under cyclic loading using non-linear finite element analysis of a single-bay single-story frame. These braces, which contain double angle and double channel brace sections, are considered in two types of single diagonal and X-braced frames. The results of this study show that current seismic provisions such as observing the 0.4 ratio for slenderness ratio of individual elements between stitch connectors are conservative in BSCBFs, and can be increased according to the type of braces. Furthermore, such increments will lead to decreasing or remaining the current middle protected zone requirements of each BSCBFs. Failure results of BSCBFs, which are related to the plastic equivalent strain growth of members and ductility capacity of the models, show that the behaviors of double channel back-to-back diagonal braces are more desirable than those of similar face-to-face ones. Also, for double angle diagonal braces, results show that the failure of back-to-back BSCBFs occurs faster in comparison with face-to-face similar braces. In X-braced frames, cyclic and failure behaviors of built-up face-to-face models are more desirable than similar back-to-back braces in general.

Application and Determination of Defended Footprint Using a Simulation Model for Ballastic Missile Trajectory (탄도미사일 궤적 시뮬레이션 모델을 이용한 방어영역 산출 및 응용)

  • Hong, Dongwg;Yim, Dongsoon;Choi, Bongwhan
    • Journal of the Korea Institute of Military Science and Technology
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    • v.21 no.4
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    • pp.551-561
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    • 2018
  • Footprint is defined as ground area that is projected from the outer edges of the battle space protected by a defence system. This concept can be effectively used for making decisions on site selection of anti missile systems to defend against enemy's ballistic missiles. In this paper, simulations of ballistic missile trajectories based on various launch conditions are performed first and then the footprint is derived with engagement zone set as a boundary condition. Results of the simulation with various relative positions between the defense system and defended asset are also presented. The proposed method, in which the trajectories are generated based on launch point of the ballistic missile, has an advantage of approximating the defended area close to reality. Two applications are introduced in the present paper to describe how the derivation of defended area could be utilized in deployment decision of defense systems.

Seasonal Community Structure and Vertical Distribution of Medicinal Seaweeds at Kkotji in Taean Peninsula, Korea (태안반도 꽃지 약용해조의 계절적 군집구조 및 수직분포)

  • Lee, Ki-Hun;Yoo, Hyun-Il;Choi, Han-Gil
    • ALGAE
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    • v.22 no.3
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    • pp.209-219
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    • 2007
  • Marine algal flora and community structure of medicinal seaweeds were examined at Kkotji of Taean Peninsula, Korea from May 2005 to January 2006. Seventy-nine seaweeds including 42 medicinal algae and one marine plant were identified. Sargassum thunbergii was the representative alga occurred at all seasons and shore levels. The dominant medicinal seaweeds were perennial S. thunbergii, Neorhodomela aculeata, and Corallina pilulifera, and ephemeral Monostroma grevillei, Porphyra yezoensis, and Ulva pertusa. Their vertical distribution were N. aculeata – P. yezoensis, M. grevillei, and U. pertusa – C. pilulifera from high to low intertidal zone. The average biomass of medicinal seaweeds varied from 34.17 g m–2 in spring to 56.41 g m–2 in summer. At Kkotji shore, the opportunistic species (Enteromorpha, Ulva, and Cladophora) and turf-forming algae (Caulacanthus okamurae and Gelidium divaricatum) were easily observed. Such fast growing ESG II (ecological state group) was 87.50% and slow growing perennial algae, ESG I was only 12.15%. Also, diversity index (H’) and dominance index (DI) indicate that the seaweed community of Kkotji is unstable. Therefore, Kkotji rocky shore should be more protected from human activities such as turbulence and eutrophication in order to maintain species diversity and abundance of medicinal seaweeds.

A Study on the Characteristics of he Space Composition of the Medium Large Size Apartments' Unit Plan in Gyeongnam (경남지역 중대형 아파트의 단위세대 평면구성 특성에 관한 연구)

  • Han, Min-Jeong
    • Journal of the Korean housing association
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    • v.19 no.5
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    • pp.1-10
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    • 2008
  • This study attempts to analyze the characteristics of the space composition of the apartments and the general principles of apartments unit plans in Gyeongnam. Literature review and content analysis method were used in his research. The data of 108 unit plans were collected from e-catalogue and model houses of housing construction firms. The results of this study were as follows; 1) The general principle of Gyeongnam apartment unit plans, the tendency of 4LDk+2BATH type, 4bay, central type living room were showed. 2) In the point LDK and couple's bed room, LDK area become large and open type and couple's bed room were showed bed room+dress+powder+bath type as Maser's zone. 3) The entrance has a intermediate space as a balcony or a former space and the privacy of LDK space was protected from the entrance. 4) In the case of support space, generally support kitchen and laundry space were offered and several balconies were utilized. In fact, he differences of apartment plan composition between central cities and Gyeongnam were no showed. Therefore, these tendencies on plan composition of apartment in Gyeongnam were followed the general principles of Korean unit plans.

A Study on Improvement of Management Framework for Coastal Erosion Protection (연안침식방지를 위한 관리체계 개선방안)

  • Lee, Moon-Suk;Park, Seong-Wook
    • Ocean and Polar Research
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    • v.29 no.2
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    • pp.155-165
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    • 2007
  • Recently, coastal erosion has become an important issue in relation to keeping territorial integrity of a nation as well as protecting the coastal marine ecosystem. This study examines some apprehensions about the effectiveness of the existing legal system concerning prevention of coastal erosion. After examining several case studies in Scotland, the USA, and the Netherlands, this study proposes appropriate revisional legal measures that can be applied in Korea: first, the coastal management act should be revised for stronger, enforceable and practical legal grounds emphasizing minimal coastal erosion; second, the proposed "Comprehensive Coastal Erosion Prevention Plan" should be established and implemented in four steps such as characterization of issues through surveys of stakeholders and demand assessment, plan establishment, execution, and maintenance and management; third, there is a demand to establish and implement a legal framework to support monitoring activities which provide important data and information to prevent coastal erosion; fourth, the chronic region of damage is designated as the "Vulnerable Area" to be protected and managed accordingly; fifth, the "Coastal Coordination council" is established and operated for developing an integrated coastal management policy and visions for sustainable coastal zone, as well as coordinating and intervention of any activities which may cause coastal erosion.

Effect of Ethanol Extract of Belamcandae Rhizoma on Dermal Bioactive Properties (사간(射干) 에탄올추출물이 피부생리활성에 미치는 영향)

  • Sung, Byung-Gon;Lee, Seong-Jin;Kim, Pill-Joo;Seo, Hyun-Chol;Kim, Dae-Sung;Mun, Yeun-Ja;Woo, Won-Hong;Lim, Kyu-Sang
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.21 no.1
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    • pp.104-112
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    • 2008
  • Objective : This experimental study was preformed to investigate the effect of ethanol extract of Belamcandae Rhizoma (EBR) on dermal bioactive properties related to cosmeceuticals such as radical scavenging activity and depigmentation. Methods : The free radical scavenging activity of EBR was assayed in cell free systems using 1,1-diphenyl-2-picrylhydrazyl (DPPH). Antibacterial potency was measured by the size of inhibition zone with change of volume. Cell viability was measured by MTT assay and tyrosinase activity was assessed using L-DOPA. Results : EBR showed slightly radical scavenging activity and protected against UVB-induced cell cytotoxicity. Futhermore, EBR showed antibacterial activities on S. epidermidis and S. aureus. Although the proliferation of B16/F10 cells was decreased by EBR, necrosis was not revealed. EBR augmented tyrosinase activity and dendrite outgrowth in B16/F10 cells. Conclusions : These results suggest that EBR has antioxidative & antibacterial activities, and stimulate melanogenesis.

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An Electrochemical Property Stud on the Corrosion Behavior of Welding Part of RE36 Steel for Marine Structure (해양구조물용 RE36강의 용접부 부식거동에 관한 전기화학적 특성 연구)

  • 김성종;김진경;문경만
    • Journal of Welding and Joining
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    • v.18 no.5
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    • pp.70-76
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    • 2000
  • The effect of Post Weld Heat Treatment(PWHT) of RE36 steel for marine structure was investigated with parameters such as micro-vickers hardness, corrosion potential and corrosion current density of weld metal(WM), base metal(BM) and heat affected zone(HAZ), and both Al alloy anode generating current and Al alloy anode weight loss quantity etc. Hardness of post-weld heat treated BM, WM and HAZ is lower than that of As-welded condition of each region. However, hardness of HAZ was the highest among those three parts regardless of PWHT temperature and corrosion potential of WM was the highest among those three parts without regard to temperature and corrosion potential of WM was the highest among those three parts without regard to PWHT temperature. The amplitude of corrosion potential difference of each other three parts at PWHT temperature $550^{\circ}C$, $650^{\circ}C$ are smaller than that of three parts by As-welded condition and corrosion current density obtained by PWHT was also smaller than that of As-welded condition. Eventually, it was known that corrosion resistance was increased by PWHT. However both Al anode generating current and anode weight loss quantity were also decreased by PWHT compare to As-welded condition when RE36 steel is cathodically protected by Al anode. Therefore, it is suggested that the optimum PWHT temperature with increasing corrosion resistance and cathodic protection effect is $550^{\circ}C$.

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A Storage Method to Enhance Cookie File Security (쿠키파일의 보안성 향상을 위한 저장 방식)

  • Sim, Won-Tae;Choi, Yo-Han;Seo, Hee-Suk;Noh, Bong-Nam
    • Journal of the Korea Society for Simulation
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    • v.20 no.1
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    • pp.29-37
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    • 2011
  • Cookie file can be properly protected by designing security zone to enhance the safety of cookie file vulnerable to cyber attacks. In this paper, the model, in which cookie file is stored in the security area and the current visiting page is closely linked with cookie, is proposed to help users utilize in the same existing way, as well as enhance the security of user cookie files. Even if attacker tries to compromise web browser's cookie folder, the security of other cookies can be preserved. It is possible since the folder has the only cookie for the current web page where user is visiting.