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Applying 9-Windows to Problem Solving (9-Windows를 이용한 문제 해결 방안)

  • Jeong, Hai Sung
    • Journal of Applied Reliability
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    • v.15 no.3
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    • pp.149-153
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    • 2015
  • One common roadblock to innovation is the inability to define the problem that needs to be solved. Main contributors to this situation are the complexity of real field and the psychological inertia. 9-Windows can help break the complexity and the psychological inertia. In this article, we attempt to propose how to link resources to space and time framework through 9-Windows. Also, we propose how to use the 9-Windows to find multiple perspectives and explore solutions to a problem. This research is expected to be a vehicle to make an effective use of 9-Windows along with TRIZ, SIT, CT, FMEA and QFD.

An AODV-Based Two Hops Dynamic Route Maintenance in MANET (MANET에서의 AODV 기반 2홉 동적 경로유지 기법 연구)

  • Moon, Dae-Keun;Kim, Hag-Bae
    • The KIPS Transactions:PartC
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    • v.14C no.2
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    • pp.191-198
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    • 2007
  • A mobile ad-hoc network (MANET) is an autonomous, infrastructure-less system that consists of mobile nodes. In MANET, on demand routing protocols are usually used because network topology changes frequently. AODV, which is a representative on demand routing protocol, operates using the routing table of each node that includes next hop of a route for forwarding packets. It maintains the established route if there is not an expiration of route or any link break. In the paper, we propose a partially adaptive route maintenance scheme (AODV-PA) based on AODV, which provides dynamic route modification of initial route for selecting the effective route using not only next hop but also next-hop of next-hop (i.e. 2-hop next node) acquired through route discovery process. In addition, the proposed scheme additionally manages the routing table for preventing exceptional link breaks by route modification using HELLO messages. We use NS 2 for the computer simulation and validate that the proposed scheme is better than general AODV in terms of packet delivery ratio, latency, routing overhead.

A routing protocol based on Context-Awareness for Energy Conserving in MANET

  • Chen, Yun;Lee, Kang-Whan
    • Journal of information and communication convergence engineering
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    • v.5 no.2
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    • pp.104-108
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    • 2007
  • Ad hoc networks are a type of mobile network that function without any fixed infrastructure. One of the weaknesses of ad hoc network is that a route used between a source and a destination is to break during communication. To solve this problem, one approach consists of selecting routes whose nodes have the most stable link cost. This paper proposes a method for improving the low power distributed MAC. This method is based on the context awareness of the each nodes energy in clustering. We propose to select a new scheme to optimize energy conserving between the clustering nodes in MANET. And this architecture scheme would use context-aware considering the energy related information such as energy, RF strength, relative distances between each node in mobile ad hoc networks. The proposed networks scheme could get better improve the awareness for data to achieve and performance on their clustering establishment and messages transmission. Also, by using the context aware computing, according to the condition and the rules defined, the sensor nodes could adjust their behaviors correspondingly to improve the network routing.

Durability Assessment of Geogrids by Reduction Factors (감소인자에 의한 지오그리드의 내구성 평가)

  • Jeon, Han Yong;Heo, Dai Young
    • Journal of the Korean Geosynthetics Society
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    • v.3 no.2
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    • pp.31-38
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    • 2004
  • Long-term stability of two type geogrids were evaluated. Membrane drawn type geogrid showed the exponential type tensile property and textile type geogrid showed the rapid increase of tensile property closer toward the break point. Accelerated creep test was done for textile type geogrid but not done for membrane drawn type geogrid because of its thermal property. Creep strain for membrane drawn type geogrid was larger than the ultimate tensile strain by tensile test and reduction factor by creep deformation of textile type geogrid was smaller than that of membrane type geogrid.

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A Study on the Context-Awareness Rule-Based Clustering technique for MANET (MANET에서 상황인식 규칙기반에 따른 에너지 보존 클러스터링 기법에 관한 연구)

  • Chi, Sam-Hyun;Lee, Kang-Whan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.4
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    • pp.1041-1047
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    • 2010
  • One of the weaknesses of ad hoc network is that a route used between a source and a destination is to break during communication. To solve this problem, one approach consists of selecting routes whose nodes have the most stable link cost. In this paper proposes a new method for improving the low power distributed MAC. The method is rule-based on the context awareness of the each nodes energy in clustering. The proposed networks scheme could get better improve the awareness for data to achieve and performance on their clustering establishment and messages transmission.

Non-Fibrillar $\beta$-Amyloid Exerts Toxic Effect on Neuronal Cells

  • Kim, Hyeon-Jin;Hong, Seong-Tshool
    • Animal cells and systems
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    • v.5 no.2
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    • pp.139-143
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    • 2001
  • Alzheimer's disease is the most common form of dementia and no cure is known so far. Extensive genetic works and in vitro experiments combined with clinical observations link amyloid $\beta$--protein (A$\beta$-) to the pathogenesis of Alzheimer's disease (AD). It was hypothesized that $A\beta$- becomes toxic when it adopts a fibrillar conformation. Recently, non-fibrillar form of $A\beta$- was observed and the potential role in the pathogenesis of AD became an interesting subject. In this study, the cytotoxicity of non-fibrillar $A\beta$- and fibrillar $A\beta$- was compared on oxidative stress, membrane damage, or nucleosome break down. Non-fibrillar $A\beta$- was not toxic in peripheral nervous system-derived cells but significantly toxic in central nervous system-derived cells while fibrillar $A\beta$- was non-selectively toxic in both cell culture. The neurotoxicity of non-fibrillar $A\beta$- was reproduced in semi-in vivo culture of mouse brain slice. In conclusion, non-fibrillar $A\beta$- could be more relevant to the selective neurodegeneration in Alzheimer's brains than fibrillar $A\beta$- and further research needs to be done for identification of the cause of AD.

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The Impact of ICT Goods Imports on Economic Growth: Evidence from Asia-Pacific Countries

  • Yoon, Sang-Chul
    • Journal of Korea Trade
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    • v.23 no.7
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    • pp.1-12
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    • 2019
  • Purpose - This paper empirically investigates the relationship between Information and Communication Technology (ICT) goods imports and economic growth with a focus on the 13 Asia-Pacific economies during 2005-2016. In particular, this paper extends the study by breaking down the data of Asia-Pacific countries into High Income Countries (HICs) and Low Income Countries (LICs) according to the difference of income levels. Design/methodology - Our empirical model employs the standard growth model based on the Barro (1998)-type growth framework. Using static panel-data technique, we estimate the effect of ICT goods imports on economic growth in the 13 Asia-Pacific economies. In addition, we also estimate a difference of the ICT goods imports-economic growth link between HICs and LICs. Findings -The estimation results indicate that ICT goods import has a significant positive effect on economic growth, while ICT goods export has a positive but statistically insignificant effect on it. When we break down the panel data into HICs and LICs in order to gain further insight, ICT goods imports has been effective in spurring growth in only LICs but not in HICs. The other supplementary results show that both domestic investment (GCF) and life expectancy (LE) have a significantly positive impact on economic growth in both HICs and LICs. Originality/value - The main findings of the paper suggest that ICT goods imports has a positive effect on economic growth in only LICs but not in HICs. This result supports the so-called 'leapfrogging' hypothesis through ICT goods imports in the Asia-Pacific countries, in which LICs are gaining more from ICT goods imports than HICs.

AFLRS: An AODV-based Fast Local Repair Scheme in Ad Hoc Networks (AFLRS: 애드 혹 네트워크에서 AODV에 기반한 빠른 경로 복구 기법)

  • 서현곤;김기형;서재홍
    • Journal of KIISE:Information Networking
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    • v.31 no.1
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    • pp.81-90
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    • 2004
  • A Mobile Ad Hoc Network (MANET) is a collection of wireless mobile nodes dynamically self-organizing in arbitrary and temporary network topologies without the use of any existing network infrastructure. The AODV (Ad Hoc On-Demand Distance Vector) Protocol is one of the typical reactive routing protocols, in that mobile nodes initiate routing activities only in the presence of data packets in need of a route. In this paper, we focus upon the local repair mechanism of AODV. When a link is broken, the upstream node of the broken link repairs the route to the destination by initiating a local route discovery process. The process involves the flooding of AODV control messages in every node within a radius of the length from the initiating node to the destination. In this paper, we propose an efficient local repair scheme for AODV called AFLRS (AODV-based Fast Local Repair Scheme). AFLRS utilizes the existing routing information in the intermediate nodes which have been on the active route to the destination before a link break occurs. AFLRS can reduce the flooding range of AODV control messages and the route recovery time because it can repair route through the intermediate nodes. For the performance evaluation of the proposed AFLRS, we have simulated the local repair mechanisms by using NS2 and AODV-UU. The performance results show that AFLRS can achieve faster route recovery than the local repair mechanism of AODV.

Implementation of Image Transmission System in Ad-Hoc Network Using AODV Routing Protocol (Ad hoc 네트워크에서 AODV 라우팅 프로토콜을 이용한 영상 전송 시스템 구현)

  • Lee, Sung-Hun;Lee, Hyung-Keun
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.7 no.6
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    • pp.92-100
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    • 2008
  • Ad-hoc network is a collection of wireless mobile hosts forming a temporary network without the aid of any centralized administration or reliable support services such as wired network and base stations. Recently, Ad-hoc networks are evolving to support multimedia contents according to expansion of ad hoc multi-hop communication system. Wireless ad-hoc network is different from the conventional wired network by frequent changes in network topology, number of routers and resources, there are a number of problems in applying conventional routing protocol to ad-hoc network. The AODV routing protocol is proposed for mobile node in ad-hoc networks. AODV protocol that provides to guarantee QoS for data transmission in ad hoc networks that link break frequently occurs. In this paper, AODV routing protocol based NDIS(Network Driver Interface Specification) is implemented. We design high performance image transmission that can operate with software(AODV) for ad-hoc networks without degradation. and verify operation of AODV routing protocol on the test bed.

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PANORAMIC MID-INFRARED VIEWS OF DISTANT CLUSTERS OF GALAXIES WITH AKARI

  • Koyama, Yusei
    • Publications of The Korean Astronomical Society
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    • v.32 no.1
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    • pp.287-291
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    • 2017
  • We present the results of our mid-infrared (MIR) observations of distant clusters of galaxies with AKARI. The wide-field of view of IRC/AKARI ($10^{\prime}{\times}10^{\prime}$) is ideally suited for studying dust-obscured star-formation (SF) activity of galaxies along the cosmic web in the distant universe. We performed a deep and wide-field $15{\mu}m$ (rest-frame ${\approx}8{\mu}m$) imaging observation of the RXJ1716+6708 cluster (z = 0.81) with IRC. We find that $15{\mu}m$-detected cluster member galaxies (with total infrared luminosities of $L_{IR}{\geq}10^{11}L_{\odot}$) are most preferentially located in the cluster outskirt regions, whilst such IR-luminous galaxies avoid the cluster centre. Our $H{\alpha}$ follow-up study of this field confirmed that a significant fraction of $15{\mu}m$-detected cluster galaxies are heavily obscured by dust (with $AH{\alpha}$>3 mag in extreme cases). The environment of such dusty star-burst galaxies coincides with the place where we see a sharp "break" of the colour-density relation, suggesting an important link between dust-obscured SF activity and environmental quenching. We also report the discovery of a new cluster candidate around a radio galaxy at z = 1.52 (4C 65.22), where we obtained one of the deepest IRC imaging datasets with all the nine filters at $2-24{\mu}m$. This field will provide us with the final, excellent laboratory for studying the dust-enshrouded SF activity in galaxies along the cosmic web at the critical epoch of cluster galaxy evolution with AKARI.