• Title/Summary/Keyword: Modular Network

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A Study on the Architecture for Avionics System of Jet Fighters (제트 전투기의 항공전자 시스템 아키텍처에 관한 연구)

  • Gook, Kwon Byeong;Won, Son Il
    • Journal of Aerospace System Engineering
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    • v.16 no.1
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    • pp.86-96
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    • 2022
  • The development trend of jet fighter's avionics system architecture is the digitization of subsystem component functions, increased RF sensor sharing, fiber optic channel networks, and modularized integrated structures. The avionics system architecture of the fifth generation jet fighters (F-22, F-35) has evolved into an integrated modular avionics system based on computing function integration and RF integrated sensor systems. The integrated modular avionics system of jet fighters should provide improved combat power, fault tolerance, and ease of jet fighter control. To this aim, this paper presents the direction and requirements of the next-generation jet fighter's avionics system architecture through analysis of the fifth generation jet fighter's avionics system architecture. The core challenge of the integrated modularized avionic system architecture requirements for next-generation fighters is to build a platform that integrates major components and sensors into aircraft. In other words, the architecture of the next-generation fighters is standardization of systems, sensor integration of each subsystem through open interfaces, integration of functional elements, network integration, and integration of pilots and fighters to improve their ability to respond and control.

A Personal Digital Library on a Distributed Mobile Multiagents Platform (분산 모바일 멀티에이전트 플랫폼을 이용한 사용자 기반 디지털 라이브러리 구축)

  • Cho Young Im
    • Journal of KIISE:Software and Applications
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    • v.31 no.12
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    • pp.1637-1648
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    • 2004
  • When digital libraries are developed by the traditional client/sever system using a single agent on the distributed environment, several problems occur. First, as the search method is one dimensional, the search results have little relationship to each other. Second, the results do not reflect the user's preference. Third, whenever a client connects to the server, users have to receive the certification. Therefore, the retrieval of documents is less efficient causing dissatisfaction with the system. I propose a new platform of mobile multiagents for a personal digital library to overcome these problems. To develop this new platform I combine the existing DECAF multiagents platform with the Voyager mobile ORB and propose a new negotiation algorithm and scheduling algorithm. Although there has been some research for a personal digital library, I believe there have been few studies on their integration and systemization. For searches of related information, the proposed platform could increase the relationship of search results by subdividing the related documents, which are classified by a supervised neural network. For the user's preference, as some modular clients are applied to a neural network, the search results are optimized. By combining a mobile and multiagents platform a new mobile, multiagents platform is developed in order to decrease a network burden. Furthermore, a new negotiation algorithm and a scheduling algorithm are activated for the effectiveness of PDS. The results of the simulation demonstrate that as the number of servers and agents are increased, the search time for PDS decreases while the degree of the user's satisfaction is four times greater than with the C/S model.

Diversity and Interaction of Pollination Network from Agricultural Ecosystems during Summer (경북과 강원지역 농업생태계에서 여름철 화분매개네트워크 다양성과 상호작용)

  • Son, Minwoong;Jung, Seongmin;Jung, Chuleui
    • Journal of Apiculture
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    • v.34 no.3
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    • pp.197-206
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    • 2019
  • Pollination is an important ecosystem service involved in plant breeding and reproduction. This study analyzed the pollination network, which is the interaction between flowering plants and flower-visiting insects in the agricultural landscape. Flower-visiting insects from blossoms of flowering crops and surrounding plants were quantitatively surveyed during summer time. The pollinator species and abundance on each flowering plant were analyzed. A total of 2,381 interactions were indentified with 154 pollinators on 30 species of plants. Species richness of the pollinators was highest in Coleoptera (34%) followed by Hymenoptera (28%), Diptera (28%) and Lepidoptera (10%). Apis mellifera dominated (50%) followed by Calliphora vomitoria (5.3%) and Xylocopa appendiculata among pollinators, and remaining wild pollinators provided complex interaction. Among plants, Platycodon grandiflorum, Perilla frutescen and Fagopyrum esculentum harbored most pollinators and showed highest interaction frequencies. In the modular analysis, Apis mellifera was located as a hub-species which connect the interaction of others, implying most important role in the network. This results provide the basic information on the pollinator species associated with each crop and pollinator habitat in which plant provide the nectar, pollen and habitat resources for wild pollinators.

Design and Implementation of a Reconfigurable Communication Terminal Platform (재구성 가능한 통신 단말 플랫폼의 설계 및 구현)

  • Lee, Kyoung-Hak;Ko, Hyung-Hwa
    • Journal of Korea Multimedia Society
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    • v.10 no.1
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    • pp.66-73
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    • 2007
  • SDR technology is a fundamental wireless access technology that combines and accommodates multiple wireless communication standards in one transceiver system through just modifying software using modular communication platforms without any hardware modifications for RF and IF signal processing on the basis of high performance DSP devices. Various communication systems that are designed under diverse and complex network environments require the communication platforms on the basis of SDR supporting reorganization to guarantee simple and fast communication interfaces among the respective wireless networks. This paper introduces a main idea on the implementation of platform on the basis of SDR and a communication platform is designed for experiments that is composed of a DSP board with TMS320C6713 CPU, a FPGA board processing IF signals, and a module with RF transceiver processing wireless LAN frequency bandwidth. Various modulation schemes(BPSK, QPSK, and 16QAM) used in communication systems are applied and tested on the designed platform and the test results shows that it is possible to design a reconfigurable communication terminal platform.

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A Context-aware Messenger for Sharing User Contextual Information (사용자 컨텍스트 공유를 위한 상황인지 메신저)

  • Hong, Jin-Hyuk;Yang, Sung-Ihk;Cho, Sung-Bae
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.9
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    • pp.906-910
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    • 2008
  • As the mobile environment becomes widely used, there is a growth on the concern about recognizing and sharing user context. Sharing context makes the interaction between human more plentiful as well as helps to keep a good social relationship. Recently, it has been applied to some messengers or mobile applications with sharing simple contexts, but it is still required to recognize and share more complex and diverse contexts. In this paper, we propose a context-aware messenger that collects various sensory information, recognizes representative user contexts such as emotion, stress, and activity by using dynamic Bayesian networks, and visualizes them. It includes a modular model that is effective to recognize various contexts and displays them in the form of icons. We have verified the proposed method with the scenario evaluation and usability test.

Secure and Efficient Access Control Protocol in Digital Broadcasting System (디지털 방송에서 안전하고 효율적인 접근 제어 프로토콜)

  • Lee, Ji-Seon;Kim, Hyo
    • The Journal of the Korea Contents Association
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    • v.10 no.3
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    • pp.32-43
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    • 2010
  • IPTV is an emerging technology that combines both broadcasting and tele-communication technologies, and provides various multi-media contents to the service subscribers. In general, IPTV broadcasters transmit scrambled signals (multi-media contents) to the paying subscribers, and the users within the acknowledged network descramble the signals using the smart-card. That is, users are verified through communication between STB (Set-Top Box) and smart-card. In 2004, Jiang et al. proposed a secure protocol regarding the verification process. The method has been modified and enhanced by several following research works. However, all the methods that have been proposed so far required modular exponentiation operations which may raise the smart-card costs. In this paper, we propose a new efficient mutual authentication and session-key establishment protocol using only hash functions and exclusive-or operations, and show that the proposed protocol is still secure under various security attacks.

Dictionary Attack on Huang-Wei's Key Exchange and Authentication Scheme (Huang-Wei의 키 교환 및 인증 방식에 대한 사전공격)

  • Kim, Mi-Jin;Nam, Jung-Hyun;Won, Dong-Ho
    • Journal of Internet Computing and Services
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    • v.9 no.2
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    • pp.83-88
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    • 2008
  • Session initiation protocol (SIP) is an application-layer prolocol to initiate and control multimedia client session. When client ask to use a SIP service, they need to be authenticated in order to get service from the server. Authentication in a SIP application is the process in which a client agent present credentials to another SIP element to establish a session or be granted access to the network service. In 2005, Yang et al. proposed a key exchange and authentication scheme for use in SIP applications, which is based on the Diffie-Hellman protocol. But, Yang et al.'s scheme is not suitable for the hardware-limited client and severs, since it requires the protocol participant to perform significant amount of computations (i.e., four modular exponentiations). Based on this observation. Huang and Wei have recently proposed a new efficient key exchange and authentication scheme thor improves on Yang et al.'s scheme. As for security, Huang and Wei claimed, among others, that their scheme is resistant to offline dictionary attacks. However, the claim turned out to be untrue. In this paper, we show thor Huang and Wei's key exchange and authentication scheme is vulnerable to on offline dictionary attack and forward secrecy.

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The Study of Web Services Adaptation in IPv6/IPv4 Coexistence Network (IPv6/IPv4 공존 환경에서의 웹서비스 적용에 관한 연구)

  • Lee, Won-Suk;In, Min-Kyo;Lee, Seung-Yun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.747-749
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    • 2005
  • The popularity of web services within the IT industry continues to grow as the next generation web technologies. Web services are self-contained, self-describing, modular applications that can be published, located, and invoked across the Web. Web services will be core technology for e-business in the Web. IPv6 is sometimes also called the Next Generation Internet Protocol and is a new version of IP which is designed to be an evolutionary step from IPv4. In this paper, we define problems for adapting web services to IPv6 Environment. This paper survey and explain consideration issues that include standards, components, coexistence of IPv6 and IPv4, etc.

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Sediment Bacterial Community Structure under the Influence of Different Domestic Sewage Types

  • Zhang, Lei;Xu, Mengli;Li, Xingchen;Lu, Wenxuan;Li, Jing
    • Journal of Microbiology and Biotechnology
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    • v.30 no.9
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    • pp.1355-1366
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    • 2020
  • Sediment bacterial communities are critical to the biogeochemical cycle in river ecosystems, but our understanding of the relationship between sediment bacterial communities and their specific input streams in rivers remains insufficient. In this study, we analyzed the sediment bacterial community structure in a local river receiving discharge of urban domestic sewage by applying Illumina MiSeq high-throughput sequencing. The results showed that the bacterial communities of sediments samples of different pollution types had similar dominant phyla, mainly Proteobacteria, Actinobacteria, Chloroflexi and Firmicutes, but their relative abundances were different. Moreover, there were great differences at the genus level. For example, the genus Bacillus showed statistically significant differences in the hotel site. The clustering of bacterial communities at various sites and the dominant families (i.e., Nocardioidaceae, and Sphingomonadaceae) observed in the residential quarter differed from other sites. This result suggested that environmentally induced species sorting greatly influenced the sediment bacterial community composition. The bacterial co-occurrence patterns showed that the river bacteria had a nonrandom modular structure. Microbial taxonomy from the same module had strong ecological links (such as the nitrogenium cycle and degradation of organic pollutants). Additionally, PICRUSt metabolic inference analysis showed the most important function of river bacterial communities under the influence of different types of domestic sewage was metabolism (e.g., genes related to xenobiotic degradation predominated in residential quarter samples). In general, our results emphasize that the adaptive changes and interactions in the bacterial community structure of river sediment represent responses to different exogenous pollution sources.

A Platform Architecture for the Integration of CORBA Technology within TMN Framework (TMN 프레임워크와 CORBA 기술의 통합을 위한 플랫폼 구조)

  • Jeong, Mun-Sang;Park, Jong-Tae
    • Journal of KIISE:Computing Practices and Letters
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    • v.5 no.6
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    • pp.801-808
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    • 1999
  • 지금까지, 전기통신망과 장비들의 관리에 대해서는 많은 연구들이 진행되었지만, TMN 상위 계층의 서비스 관리와 비즈니스 관리에 대한 연구는 많이 수행되지 못했다. 최근 전세계적으로 TMN 상위 계층의 관리기능 구현을 위해서 CORBA 기술을 적용하고자하는 관심이 증가하고 있다. 본 논문에서는, 정보모델과 상호운용에 관한 TMN과 CORBA의 주요특징들을 비교하고, TMN 프레임웍와 효율적인 CORBA 기술 연동을 위한 플랫폼 구조를 제안한다. 제안된 구조에서, TMN 관리 정보를 CORBA IDL 인터페이스로 변환해주는 GDMO/ASN.1 - CORBA IDL 변환기가 고안, 구현되었고, JIDM의 상호 작용 변환의 구현을 위해서 TMN/CORBA 게이트웨이 또한 고안되었다. 그리고 이러한 기능의 확장을 위해서 모듈 형식으로 라이브러리들과 코드 생성기들이 설계, 구현되었다.Abstract Up to now, a lot of efforts have been made for the management of telecommunication networks and equipment, but less effort has been made for the realization of higher-layer service and business management. There are recently worldwide growing interests for applying CORBA technology for the realization of higher layer Telecommunication Management Network (TMN) management functions. In this paper, we compare the features of TMN and CORBA with respect to information model, and operational behavior. And then, we propose a platform architecture for the efficient integration of CORBA technology within TMN framework. Within platform architecture, GDMO/ASN.1 to IDL translator has been designed and implemented for translating TMN management information into CORBA IDL interface. The TMN/CORBA gateway is also designed for realization of the interaction translation specification of JIDM task force. The libraries and code generators have been designed and implemented in a modular fashion to provide the functional extensibility.