• Title/Summary/Keyword: Line of Defence

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Seismic performance of gravity-load designed concrete frames infilled with low-strength masonry

  • Siddiqui, Umair A.;Sucuoglu, Haluk;Yakut, Ahmet
    • Earthquakes and Structures
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    • v.8 no.1
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    • pp.19-35
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    • 2015
  • This study compares the seismic performances of two reinforced concrete frame specimens tested by the pseudo-dynamic procedure. The pair of 3-storey, 3-bay frames specimens are constructed with typical characteristics of older construction which is lacking seismic design. One of the specimens is a bare frame while the other is infilled with low-strength autoclave aerated concrete (AAC) block masonry. The focus of this study is to investigate the influence of low strength masonry infill walls on the seismic response of older RC frames designed for gravity loads. It is found that the presence of weak infill walls considerably reduce deformations and damage in the upper stories while their influence at the critical ground story is not all that positive. Infill walls tend to localize damage at the critical story due to a peculiar frame-infill interaction, and impose larger internal force and deformation demands on the columns and beams bounding the infills. Therefore the general belief in earthquake engineering that infills develop a second line of defence against lateral forces in seismically deficient frames is nullified in case of low-strength infill walls in the presented experimental research.

Anti-Oxidant Efficiency and Memchanisms of Phytochemicals from Traditional Herbal Medicine (한약재-식물성천연화학물질의 항산화 효능 및 기전)

  • Kim, Jong-Bong
    • Journal of Society of Preventive Korean Medicine
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    • v.12 no.1
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    • pp.103-118
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    • 2008
  • Antioxidants are compounds that protect cells against the damaging effects of reactive oxygen species (ROS). Some ROS, such as superoxide and hydrogen peroxide, are normally produced in cells as by-products of biochemical reactions or as signaling molecules. When ROS-generating reactions are activated excessively, pathological quantities of ROS are released to create an imbalance between antioxidants and ROS, called as oxidative stress. Oxidative stress, which may result in cellular damage, has been linked to cardiovascular disease, diabetes, cancer, and other degenerative conditions. In humans the first line of antioxidant defence are the antioxidant enzymes, especially SOD, glutathione peroxidase (GPX), and to a lesser extent catalase, as well as the tripeptide glutathione(GSH). These enzymes will help destroy ROS(reactive oxygen species) such as hydroxyl radical, $H_2O_2$ and lipid peroxides, while GSH protects against oxidized protein. Many herbal medicines possess antioxidant properties. Herbal antioxidants may protect against these diseases by contributing to the total antioxidant defense system of the human body. Here, many herbal medicines including Ginseng, Licorice, Ligusticum Chuanxiong, Ginkgo biloba and many others was reviewed in terms of anti-oxidant efficiency related to their components.

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Unlimited Liability

  • Mckay, John S.
    • The Korean Journal of Air & Space Law and Policy
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    • v.6
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    • pp.137-147
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    • 1994
  • Clearly there are many legal arguments and criticisms surrounding the proposals for change in the Warsaw Convention and the need for a radical review. The question remains is unlimited liability the answer or should there be some other form of supplemental compensation and if so, what limits should be applicable. It does seem that the adopted limits of the Convention are seen by many as the first line of defence, which, dependent on political and cultural differences, the legal interpretation of contractual wording and the legal system globally have resulted in enormous differences in compensation paid whether or not the Convention limits were imposed. An example of this is in the United States, which highlights the significance of the problem in that domestic travellers without Convention Limits can, through the American legal system, obtain compensation in the multi-million dollar area for a death claim, whereas a passenger t1ying internationally would in the first instance be subject to Convention Limits. expensive legal action through litigation. To date, we can advise that insurers have not charged additional premium for unlimited liability coverage. Insurance rates as we have stated are hardening considerably. To date, average rate increases have been plus 56% for aircraft hull and plus 45% for liabilities. Insurers last year suffered global losses of around US $ 1.1 Billion against a premium income of US $ 800,000. The target premium income for 1993 is believed to be in the region of US $1.4 Billion.

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A Report on Utilizing Local Food as Tourism Resource of Northern Gyong-gi Province (경기 북부지역의 관광자원으로서 향토음식에 대한 고찰)

  • 남정혜;최태호
    • The Korean Journal of Food And Nutrition
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    • v.14 no.5
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    • pp.479-484
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    • 2001
  • Gyong-gi province has been the political, social, economical center of Korea since the three Kingdom period, Koryo, Chosun dynasty. As a result, the area enjoys abundant local food culture. However, due to the truce line going through the province, it was divided into northern and southern region. Development of the northern Gyong-gi province has been restricted because of security and defence reasons. So, even though it has kept abundant local food heritage compared to other regions. local food products have not been fully developed. Furthermore, as bed towns of Seoul and new towns are constructed in this region, traditional and local culture has been vanished gradually and the regional uniqueness is disappearing. This report focuses on identifying unique local foods of northern Gyong-gj province where tourist site development is limited and finding out how to utilize these as international tourism resource in the 21$\^$th/ century, the era of reunified Korea. Now, we need to seek ways to overcome the current difficulties and utilize the heritage of food culture and develop It in a form that suits the taste of modern consumers.

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On Designing a Robust Control System Using Immune Algorithm (면역 알고리즘을 이용한 강건한 제어 시스템 설계)

  • Seo, Jae-Yong;Won, Kyoung-Jae;Kim, Seong-Hyun;Cho, Hyun-Chan;Jeon, Hong-Tae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.8 no.6
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    • pp.12-20
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    • 1998
  • As an approach to develope a control system with high robustness in changing control environment conditions, this paper will propose a robust control system, using multilayer neural network and biological immune system. The proposed control system adjusts weights of the multilayer neural network(MNN) with the immune algorithm. This algorithm is made up of two major divisions, the innate immune algorithm as a first line of defence and the adaptive immune algorithm as a barrier of self-adjustment. Using the proposed control system based on immune algorithm, we will work out a design for the controller of a robot manipulator. And we will demonstrate the effectiveness of the control system of robot manipulator with computer simulations.

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MONITORING OF BAR TRANSFORMATION IN THE HAN RIVER ESTUARY USING RADARSAT/SAR IMAGES

  • Yang, Chan-Su;Han, Hee-Jeong;Park, Jin-Kyu;Ouchi, Kazuo
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.856-859
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    • 2006
  • In river with bar, the characteristics of its physical conditions have a close relationship with bar morphology. In this paper, a monitoring approach of bar transformation in the Han River Estuary is presented using RADARSAT/SAR Images. The estuary is divided into North and South Korea and its area is blocked by CCL(Civil Control Line). Satellite remote sensing, therefore, is uniquely suited to monitoring bar transformation. Based on SAR signatures for bars, bar transformation is investigated from 2000 to 2005, and monitoring of suspended-silt transportations from terrestrial runoff is tried to understand the morphology during the events of severe rain storm. SAR data did not reveal clearly the bar locations because of most of data acquisitions during high tides from 6.8 m to 9.0 m. Even though the problem, it could be said that in the estuary vegetated area and natural levees are developed well, but bars and shifted after an event like a flood. It is also showed that suspended solids such as silt transported through the estuary could contribute highly to a sedimentation environment around Incheon.

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A comparison of individual and combined $_L$-phenylalanine ammonia lyase and cationic peroxidase transgenes for engineering resistance in tobacco to necrotrophic pathogens

  • Way, Heather M.;Birch, Robert G.;Manners, John M.
    • Plant Biotechnology Reports
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    • v.5 no.4
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    • pp.301-308
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    • 2011
  • This study tested the relative and combined efficacy of ShPx2 and ShPAL transgenes by comparing Nicotiana tabacum hybrids with enhanced levels of $_L$-phenylalanine ammonia lyase (PAL) activity and cationic peroxidase (Prx) activity with transgenic parental lines that overexpress either transgene. The PAL/Prx hybrids expressed both transgenes driven by the 35S CaMV promoter, and leaf PAL and Prx enzyme activities were similar to those of the relevant transgenic parent and seven- to tenfold higher than nontransgenic controls. Lignin levels in the PAL/Prx hybrids were higher than the PAL parent and nontransgenic controls, but not significantly higher than the Prx parent. All transgenic plants showed increased resistance to the necrotrophs Phytophthora parasitica pv. nicotianae and Cercospora nicotianae compared to nontransgenic controls, with a preponderance of smaller lesion categories produced in Prx-expressing lines. However, the PAL/Prx hybrids showed no significant increase in resistance to either pathogen relative to the Prx parental line. These data indicate that, in tobacco, the PAL and Prx transgenes do not act additively in disease resistance. Stacking with Prx did not prevent a visible growth inhibition from PAL overexpression. Practical use of ShPAL will likely require more sophisticated developmental control, and we conclude that ShPx2 is a preferred candidate for development as a resistance transgene.

Design and Manufacture of Modified Ring antenna with Stub and Ground Slot for WLAN Applications (WLAN 시스템에 적용 가능한 그라운드 슬롯과 stub를 갖는 변형된 링 안테나 설계와 제작)

  • Koo, Yung-Seo;Im, Dae-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.10
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    • pp.2265-2272
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    • 2013
  • In this paper, a dual-band circular ring monopole antenna with stub and ground slot for is proposed WLAN(Wireless Local Area Networks) applications. The proposed antenna is based on a planar monopole design, and composed of one circular ring of radiating patches, and modified feed line, and rectangular slot in the ground plane for dual-band operation. To obtain the optimized parameters, we used the simulator, Ansoft's High Frequency Structure Simulator(HFSS) and found the parameters that effect antenna characteristics. Using the obtained parameters, the antenna is fabricated, and the return loss coefficient, gain, and radiation patterns are determined for WLAN application.

A Study on the Electromagnetic Modeling and Network Analysis for GTEM Cell Design (GTEM 셀 설계를 위한 전자파 모델링 및 회로망 해석 기법 연구)

  • Lee, Woo-Sang
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.19 no.7
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    • pp.791-799
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    • 2008
  • In this paper, the electromagnetic modeling and network analysis are proposed for design of GTEM cell operating from DC to 18 GHz. 3D electromagnetic numerical analysis models composed of the coaxial mode-converter for the feeder of GTEM cell, 5 m expanded rectangular coaxial transmission line, and the resistive termination load for current and field transmitted from the feeder are developed. Equivalent network model of feeder, transmission line, and termination load in the GTEM cell is also proposed, so the return loss of GTEM cell is calculated using S-parameters using the electromagnetic numerical analysis. To verify the proposed design method, the GTEM cell is designed, constructed and tested, with its size of $5{\times}2.5{\times}1.7\;m$ and operating frequency of $DC{\sim}18\;GHz$.

Analysis of the range estimation error of a target in the asynchronous bistatic sonar (비동기 양상태 소나의 표적 거리 추정 오차 분석)

  • Jeong, Euicheol;Kim, Tae-Hwan
    • The Journal of the Acoustical Society of Korea
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    • v.39 no.3
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    • pp.163-169
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    • 2020
  • The asynchronous bistatic sonar needs to estimate direct blast arrival time at a receiver to localize targets, and therefore the direct blast arrival time estimation error could be added to target localization error in comparison with synchronous system. Direct blast especially appears as several peaks at the matched filter output by multipath, thus we compared the first peak detection technique and the maximum peak detection technique of those peaks for direct blast arrival time estimation through sea trial data. The test was performed in a shallow sea with bistatic sonar made up of spatially separated source and line array sensors. Line array sensors obtained the target signal which is generated from the echo repeater. As a result, the first peak detection technique is superior to maximum peak detection technique in direct blast arrival time estimation error. The result of this analysis will be used for further research of target tracking in the asynchronous bistatic sonar.