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A study on improvements of disaster management with public-private partnerships (재난관리 민관협력 개선방안 연구)

  • Yoo, Soonduck
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.2
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    • pp.171-180
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    • 2016
  • The purpose of this research is to study how efficiently corporate public-private partnerships in disaster management is. The research method involved interviewing fifteen experts in disaster management, who were questioned about assisting disaster-stricken areas in accordance with public-private partnerships. These experts offered the following suggestions for improving disaster management methodology. First, to overcome the lack systematic management in the public-private partnerships for disaster relief to expand and strengthen the role of civil organizations. Second, disaster managers and private organizations should have active communication along secure channels so that private organizations can take advantage of the talents that public and private entities own. Third, for civilian experts to share their information, which should be actively utilized to support disaster management in local government. Fourth, education and training for public-private partnerships should be made on an ongoing basis. Fifth, effective disaster management and recognition of public-private cooperation should be strengthened. Finally, private sector support should be made. This study was applied to the Delphi method and that improvements can be made to a variety of populations, such as questionnaires. The results of this study will contribute to the policy options for establishing public-private partnerships in disaster management.

Symbol Timing Alignment and Combining Technique in Rake Receiver for cdma2000 Systems (cdma2000 시스템용 레이크 수신기에서의 심볼 정렬 및 컴바이닝 기법)

  • Lee, Seong-Ju;Kim, Jae-Seok;Eo, Ik-Su;Kim, Gyeong-Su
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.1
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    • pp.34-41
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    • 2002
  • In the conventional rake receiver structure for the IS-95 CDMA system, each finger has its own time-deskew buffer or FIFO that aligns the multipath signals to the same timing reference in order to combine symbols. This architecture is not a burden to the rake receiver design mainly because of the small number and size of the buffers. However, the number and size of the buffers are significantly increased in the cdma2000 system which adopts multiple carriers and the small spreading gain for a higher rate in data services. In order to decrease the number of buffers, we propose a new model of the time-deskew buffers, which combines the symbols as well as realigns them at the same time. Our architecture reduces the hardware complexity of the buffers by about more than 60% and 70% compared with the conventional one when we consider each rake receiver has three and four independent fingers, respectively. Moreover, the proposed algorithm is very useful not only to the cdma2000 rake receiver but also to the receiver with many fingers in order to increase the BER performance.

Space-Time Concatenated Convolutional and Differential Codes with Interference Suppression for DS-CDMA Systems (간섭 억제된 DS-CDMA 시스템에서의 시공간 직렬 연쇄 컨볼루션 차등 부호 기법)

  • Yang, Ha-Yeong;Sin, Min-Ho;Song, Hong-Yeop;Hong, Dae-Sik;Gang, Chang-Eon
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.1
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    • pp.1-10
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    • 2002
  • A space-time concatenated convolutional and differential coding scheme is employed in a multiuser direct-sequence code-division multiple-access(DS-CDMA) system. The system consists of single-user detectors (SUD), which are used to suppress multiple-access interference(MAI) with no requirement of other users' spreading codes, timing, or phase information. The space-time differential code, treated as a convolutional code of code rate 1 and memory 1, does not sacrifice the coding efficiency and has the least number of states. In addition, it brings a diversity gain through the space-time processing with a simple decoding process. The iterative process exchanges information between the differential decoder and the convolutional decoder. Numerical results show that this space-time concatenated coding scheme provides better performance and more flexibility than conventional convolutional codes in DS-CDMA systems, even in the sense of similar complexity Further study shows that the performance of this coding scheme applying to DS-CDMA systems with SUDs improves by increasing the processing gain or the number of taps of the interference suppression filter, and degrades for higher near-far interfering power or additional near-far interfering users.

국내 인터넷전문은행 설립시 예상되는 전자금융리스크에 대한 대응방안 연구

  • Kim, Tae-Ho;Park, Tae-Hyoung;Lim, Jong-In
    • Review of KIISC
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    • v.18 no.5
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    • pp.33-48
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    • 2008
  • 최근 은행의 소유지분한도와 설립자본금 등에 대한 정부의 금융규제 완화로 인터넷전문은행의 설립 가능성이 높아지고 있다. 그러나 우리나라의 전자금융환경은 전자금융거래법 제정에 따라 금융기관의 입증책임을 강화함으로써 금융기관의 전자금융리스크가 상대적으로 크게 증가하였다. 또한, 정보 공격기술 및 수법의 발달로 전자금융보안에 대한 위협이 지속적으로 증가하고 있다. 이외 에도 신BIS 리스크 평가에 IT운영리스크가 포함되는 등 금융환경 변화 및 정보통신 기술의 발전으로 인한 전자금융리스크가 계속 확대되고 있는 추세에 있다. 이러한 금융환경 변화와 함께 서비스채널이 인터넷에 집중되는 인터넷전문은행은 기존의 전통적인 은행과 차별되는 리스크에 추가적으로 노출될 위험성이 높다. 이러한 리스크에 대한 인식 및 대비 부재는 금융소비자가 금융권 전자금융거래에 대한 불신으로 확산되거나, 금융시장의 불안정성을 야기하는 금융사고로 이어져 자칫 국내 전자금융의 발전을 저해하는 심각한 요소가 될 수 있다. 본 논문에서는 국내 금융환경과는 차이가 있지만, 인터넷전문은행이 가져올 전자금융의 기술적 변화는 유사하다는 점에서 해외 주요국가의 인터넷전문은행 현황과 전자금융부문을 중심으로 인터넷전문은행 설립인가 사례를 살펴보고, 국내에서 인터넷전문은행 설립시 우리가 취해야 할 입장에 대해 시사점을 얻고자 하였다. 그리고 국내 전자금융 환경에서 전통적인 일반은행과 차별되거나 인터넷전문은행 고유의 특성으로 발생되는 주요 전자금융리스크를 다섯 가지로 분석하였고, 이러한 전자금융리스크를 줄이기 위한 대응방안을 모색해 보았다. 정부의 금융규제 완화는 금융자유화를 진전시켜 금융거래가 자유경쟁원리에 입각해 이루어짐에 따라 국민경제의 발전에 있어서 바람직한 결과를 얻고자 하는 것이다. 그러나 다른 한편으로 과도한 리스크에 노출 될 경우에는 금융시장의 불안정성을 야기하고 이로 인해 역 선택과 도덕적 해이를 야기 시키는 등 여러 가지의 폐해를 줄 수도 있다 이러한 폐해를 줄이기 위해서는 인터넷전문은행의 고유한 특성으로 수반되는 리스크와 상대적으로 그 중요성이 부각되는 전자금융리스크에 대한 관리 감독을 강화해야 한다. 또한 이러한 리스크 관리강화를 위한 제도적 장치는 인터넷전문은행의 자율성과 책임성을 부여하는 방향으로 이루어지는 것이 바람직하다. 인터넷전문은행이 실질적으로 다수의 금융이용자에게 다양한 혜택과 효율적인 금융서비스를 제공하기 위해서는 초기 사업계획 심사 단계에서부터 위험성이 크게 증가하는 전자금융리스크에 대해서, 적절한 관리방안 수립을 통해 예상되는 리스크를 줄이기 위한 노력이 필요하다고 생각한다. 그리고 인터넷전문은행에 대한 구체적인 인가요건이 마련되지 못한 현 상황에서, 국내 인터넷전문은행 설립이 우리나라 전자금융거래에 발전적 역할을 할 수 있도록 앞으로 더 많은 논의와 연구가 진행될 필요가 있다.

An Efficient Group Key Distribution Mechanism for the Secure Multicast Communication in Mobile Ad Hoc Networks (이동 애드혹 네트워크에서 안전한 멀티캐스트 통신을 위한 효율적인 그룹 키 분배 방식)

  • Lim Yu-Jin;Ahn Sang-Hyun
    • The KIPS Transactions:PartC
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    • v.13C no.3 s.106
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    • pp.339-344
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    • 2006
  • Secure delivery of multicast data can be achieved with the use of a group key for data encryption in mobile ad hoc network (MANET) applications based on the group communication. However, for the support of dynamic group membership, the group key has to be updated for each member joining/leaving and, consequently, a mechanism distributing an updated group key to members is required. The two major categories of the group key distribution mechanisms proposed for wired networks are the naive and the tree-based approaches. The naive approach is based on unicast, so it is not appropriate for large group communication environment. On the other hand, the tree-based approach is scalable in terms of the group size, but requires the reliable multicast mechanism for the group key distribution. In the sense that the reliable multicast mechanism requires a large amount of computing resources from mobile nodes, the tree-based approach is not desirable for the small-sized MANET environment. Therefore, in this paper, we propose a new key distribution protocol, called the proxy-based key management protocol (PROMPT), which is based on the naive approach in the small-sized MANET environment. PROMPT reduces the message overhead of the naive through the first-hop grouping from a source node and the last-hop grouping from proxy nodes using the characteristics of a wireless channel.

Implementation of 500BASE-T with 2 Pairs UTP (2조 UTP를 이용한 500BASE-T의 구현)

  • Chung, Hae;Jeon, Seong-Bae;Kim, Jin-Hee;Park, Hyung-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.10B
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    • pp.1150-1158
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    • 2011
  • More than 100 Mbps rate is needed in the UBcN for a subscriber to receive broadband traffics with multi-channel like UDTV or 3DTV. Although the optical fiber is recently deployed for the FTTH, the UTP is the most widely used medium and will be used in UBcN age. Network providers may consider the 1000BASE-T or the vectorized VDSL if they adopts the UTP in the place where does not have optical fibers. But UTP should be expanded because 1000BASE-T and vectorized UTP needs 4 and 3 pairs cable, respectively while residential region has not exceeding 2 pair UTP cable. To solve the problem, we propose a 500BASE-T technology using 2 pairs UTP in this paper. The technology introduces a rate adaptation sublayer and a SERDES sublayer above and under the PCS, respectively. The rate adaptation sublayer is compatible for the GMII. Also, if we modify the SERDES sublayer, the technology can easily obtain 250BASE-T with 2 pairs UTP. We implement such functions with FPGA and analog board and verify the function of rate adaptation and symbol vector synchronization, and effective transmission rate by experiments. In particular, we show that link efficiency is increased by enable control in the rate adaptation sublayer.

An Enhanced DESYNC Scheme for Simple TDMA Systems in Single-Hop Wireless Ad-Hoc Networks (단일홉 무선 애드혹 네트워크에서 단순 TDMA 시스템을 위한 DESYNC 알고리즘 개선 방안)

  • Hyun, Sanghyun;Lee, Jeyul;Yang, Dongmin
    • KIPS Transactions on Computer and Communication Systems
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    • v.3 no.9
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    • pp.293-300
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    • 2014
  • TDMA(Time Division Multiple Access) is a channel access scheme for shared medium networks. The shared frequency is divided into multiple time slots, some of which are assigned to a user for communication. Techniques for TDMA can be categorized into two classes: synchronous and asynchronous. Synchronization is not suitable for small scale networks because it is complicated and requires additional equipments. In contrast, in DESYNC, a biologically-inspired algorithm, the synchronization can be easily achieved without a global clock or other infrastructure overhead. However, DESYNC spends a great deal of time to complete synchronization and does not guarantee the maximum time to synch completion. In this paper, we propose a lightweight synchronization scheme, C-DESYNC, which counts the number of participating nodes with GP (Global Packet) signal including the information about the starting time of a period. The proposed algorithm is mush simpler than the existing synchronization TDMA techniques in terms of cost-effective method and guarantees the maximum time to synch completion. Our simulation results show that C-DESYNC guarantees the completion of the synchronization process within only 3 periods regardless of the number of nodes.

An Artificial Visual Attention Model based on Opponent Process Theory for Salient Region Segmentation (돌출영역 분할을 위한 대립과정이론 기반의 인공시각집중모델)

  • Jeong, Kiseon;Hong, Changpyo;Park, Dong Sun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.7
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    • pp.157-168
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    • 2014
  • We propose an novel artificial visual attention model that is capable of automatic detection and segmentation of saliency region on natural images in this paper. The proposed model is based on human visual perceptions in biological vision and contains there are main contributions. Firstly, we propose a novel framework of artificial visual attention model based on the opponent process theory using intensity and color features, and an entropy filter is designed to perceive salient regions considering the amount of information from intensity and color feature channels. The entropy filter is able to detect and segment salient regions in high segmentation accuracy and precision. Lastly, we also propose an adaptive combination method to generate a final saliency map. This method estimates scores about intensity and color conspicuous maps from each perception model and combines the conspicuous maps with weight derived from scores. In evaluation of saliency map by ROC analysis, the AUC of proposed model as 0.9256 approximately improved 15% whereas the AUC of previous state-of-the-art models as 0.7824. And in evaluation of salient region segmentation, the F-beta of proposed model as 0.7325 approximately improved 22% whereas the F-beta of previous state-of-the-art models.

A Case Study on Implementation of the Shipping Market Information Service System (해운시황정보서비스시스템 구현 사례연구)

  • Lee, Seokyong;Jeong, Myounghwan
    • Journal of Korea Port Economic Association
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    • v.29 no.3
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    • pp.73-94
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    • 2013
  • The necessity of shipping market information services has been on the rise which emphasizes the relevance of transaction information and market information to parties both in and outside the shipping industry. However, previous related researches have been restricted to explorations limited by the offerings of existing shipping market information providers. Users today require effective information, an efficient contents management system, interfacing to help the information provider, graphing and spread sheets to facilitate and present the analyzed information through diverse formats, and reliable web and mobile services to provide information effectively with limited human resources. As a first step, service information has to be defined, so that it takes into account user utility, information retrieval and data development. Second, benchmark information and services must be provided from leading shipbrokers and research institutes. Third, a review of the latest technical trends is required to identify the most suitable technologies for servicing shipping market information. Finally, analysis is required on the implementation of a system with selected technologies, as well as the development of channels to post information which have been analyzed by users. Such a process would enable the continual redefinition of the shipping market information users actively need. The application of an X-Internet based WCMS, with a single-window dashboard providing user-customized information, and used to obtain and manage processes, add spread sheets to sustain calculations using the latest information, graph results, and to input additional information following predefined rules. Access to data and use of the system would require agreement that the system will incorporate user data and user-analyzed information into the market report, web portal, and hybrid app to provide current shipping market information appropriately and accurately to service users.

Analysis on Spectral Regrowth of Bandwidth Expansion Module by Quadrature Modulation Error in Digital Chirp Generator (디지털 첩 발생기에서의 직교 변조 오차에 의한 대역 확장 모듈에서의 스펙트럴 재성장 분석)

  • Kim, Se-Young;Sung, Jin-Bong;Lee, Jong-Hwan;Yi, Dong-Woo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.7
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    • pp.761-768
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    • 2010
  • This paper presents an effective method to achieve the wideband waveform for high resolution SAR(Synthetic Aperture Radar) using the frequency multiplication technique. And also this paper analyzes the root causes for the spectral regrowth due to 3rd-order intermodulation in chirp bandwidth expansion scheme using quadrature modulator and frequency multipliers. The amplitude and phase imbalance requirement are defined based on the simulation results in terms of quadrature channel imbalance. This minimizes the degradation of range resolution, peak sidelobe ratio and integrated sidelobe ratio. The wideband chirp generator using the frequency multiplier and memory map scheme was manufactured and the compensation technique was presented to reduce the spectral regrowth of SAR waveform by minimizing the amplitude and phase imbalance. After I and Q channel imbalance adjustment, the carrier level reduces -28.7 dBm to -53.4 dBm. Chirp signal with 150 MHz bandwidth at S-band expands to 600 MHz bandwidth at X-band. The sidelobe levels are reduced by about 8 to 9 dB by compensating the amplitude balance between I and Q channels.