• Title/Summary/Keyword: technical specifications

Search Result 261, Processing Time 0.046 seconds

Tendency and Technical Standard of Radio Frequency for High Performance Radio Local Area Network (고속 무선 LAN의 동향 및 RF에 관한 기술기준)

  • 허보진;박진아;정찬형;박덕규
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2000.05a
    • /
    • pp.348-351
    • /
    • 2000
  • In order to enact the technical standard of RF(Radio Frequency) in domestic, this paper analyzes the trends and the technical specifications of high performance radio local area network, for example HIPERLAN(Europe), U-Nll(U.S.A), broadband mobile access system(Japan). The contents of this paper are helpful to make a rule for the desirable national technical standard of high performance radio local area network.

  • PDF

Analysis of Payload Technical Specifications for Efficient Agriculture and Forestry Satellite Observation (효율적인 농림업 위성관측을 위한 탑재체 기술사양 분석)

  • Kim, Bum-Seung;Lee, Kyung-Do;Hong, Suk-Young;Lee, Woo-Kyung
    • Korean Journal of Remote Sensing
    • /
    • v.32 no.3
    • /
    • pp.287-305
    • /
    • 2016
  • Over the past half century, satellites have continuously expanded their roles in remote sensing applications. As the number of satellites to be launched are expected to continuously increase in coming years, the research on satellite payloads will be in high demands. Earth Observation (EO) satellites are nowadays widely utilized for various purposes. Especially, Agriculture and forestry applications are considered as their major application areas. Since about 85% of domestic land cover is classified as forest or cropland areas, it would be reasonable to suggest that the demand for these satellites should be of high priority. In this paper, a comprehensive analysis is performed on the technical specifications of satellite payloads that may be applicable to agricultural applications. We attempted to build a solid database on payload specifications by collecting relevant information available from various related institutes and academic research works. A number of experts involved in national agricultural research and satellite development programs have been invited to investigate required payload design. Based on the current technology development status and future plan, multiple options for future satellite payload designs have been suggested bearing in mind that the results may be applicable to the future agriculture and forestry satellite payload design. The proposed payload specifications are analyzed in depth through satellite operation simulations under the mission of observing the national agriculture areas. The proposed design scheme and simulation results may be used as technical references to satellite payload design for future space missions.

On Improving the Reverse Engineering Process by Effectively Utilizing the Functional Models (기능 모델의 효과적인 활용을 통한 역공학 프로세스의 개선에 관한 연구)

  • Lee, Byoung-Gil;Lee, Jae-Chon
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.13 no.2
    • /
    • pp.258-267
    • /
    • 2010
  • The necessity of the new system development arises in both defence and commercial systems industry either when a breakthrough in technology needs to be realized in the form of a brand-new system or when the existing product already in operation needs to be upgraded to satisfy the increasing stakeholder's requirements. In the latter case, it is not rare that specific system technical specifications on the existing products are not available. The purpose of this study is to investigate how to handle the difficulty when an upgraded system is required to be developed based on the existing product whose detailed technical specifications cannot be obtained. A step-by-step process is described based on the reverse engineering of the existing product. As a result, a logical system model is obtained for the product. The process developed is further enhanced and evaluated by the computer-aided system engineering tool. The resulting logical system model should be helpful in the next phase of the new product development.

Anti-Jamming and Time Delay Performance Analysis of Future SATURN Upgraded Military Aerial Communication Tactical Systems

  • Yang, Taeho;Lee, Kwangyull;Han, Chulhee;An, Kyeongsoo;Jang, Indong;Ahn, Seungbeom
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.16 no.9
    • /
    • pp.3029-3042
    • /
    • 2022
  • For over half a century, the United States (US) and its coalition military aircrafts have been using Ultra High Frequency (UHF) band analog modulation (AM) radios in ground-to-air communication and short-range air-to-air communications. Evolving from this, since 2007, the US military and the North Atlantic Treaty Organization (NATO) adopted HAVE QUICK to be used by almost all aircrafts, because it had been revealed that intercepting and jamming of former aircraft communication signals was possible, which placed a serious threat to defense systems. The second-generation Anti-jam Tactical UHF Radio for NATO (SATURN) was developed to replace HAVE QUICK systems by 2023. The NATO Standardization Agreement (STANAG) 4372 is a classified document that defines the SATURN technical and operational specifications. In preparation of this future upgrade to SATURN systems, in this paper, the SATURN technical and operational specifications are reviewed, and the network synchronization, frequency hopping, and communication setup parameters that are controlled by the Network (NET) Time, Time Of Day (TOD), Word Of Day (WOD), and Multiple Word of Day (MWOD) are described in addition to SATURN Edition 3 (ED3) and future Edition 4 (ED4) basic features. In addition, an anti-jamming performance analysis (in reference to partial band jamming and pulse jamming) and the time delay queueing model analysis are conducted based on a SATURN transmitter and receiver assumed model.

Retrieval methodology for similar NPP LCO cases based on domain specific NLP

  • No Kyu Seong ;Jae Hee Lee ;Jong Beom Lee;Poong Hyun Seong
    • Nuclear Engineering and Technology
    • /
    • v.55 no.2
    • /
    • pp.421-431
    • /
    • 2023
  • Nuclear power plants (NPPs) have technical specifications (Tech Specs) to ensure that the equipment and key operating parameters necessary for the safe operation of the power plant are maintained within limiting conditions for operation (LCO) determined by a safety analysis. The LCO of Tech Specs that identify the lowest functional capability of equipment required for safe operation for a facility must be complied for the safe operation of NPP. There have been previous studies to aid in compliance with LCO relevant to rule-based expert systems; however, there is an obvious limit to expert systems for implementing the rules for many situations related to LCO. Therefore, in this study, we present a retrieval methodology for similar LCO cases in determining whether LCO is met or not met. To reflect the natural language processing of NPP features, a domain dictionary was built, and the optimal term frequency-inverse document frequency variant was selected. The retrieval performance was improved by adding a Boolean retrieval model based on terms related to the LCO in addition to the vector space model. The developed domain dictionary and retrieval methodology are expected to be exceedingly useful in determining whether LCO is met.

Optimal Design of Transformer Cores Using DEAS (DEAS를 이용한 변압기 코아의 최적설계)

  • Kim, Jong-Wook;Cha, Sang-Yun;Kim, Jae-Kwan
    • Proceedings of the KIEE Conference
    • /
    • 2005.07b
    • /
    • pp.917-920
    • /
    • 2005
  • This paper introduces an optimal design technique for a 250-watt isolation transformer using a recently developed optimization method, dynamic encoding algorithm for searches(DRAS). Although the optimal design technique for transformers dates back to 1970s and local optimization is often undertaken using FEM nowadays, literature concerning global optimization of transformer cores is rarely found against its importance. In this paper, a small isolation transformer is used as a model to be optimized with application of DEAS to corresponding mathematical description. The optimization result confirms that DEAS can be successfully employed to design transformer cores for various design specifications only by changing cost functions.

  • PDF

MANAGEMENT OF DIGITAL DESIGN DATA IN BUILDING DESIGN AND CONSTRUCTION UNITS

  • Linas Gabrielaitis ;Romualdas Bausys
    • International conference on construction engineering and project management
    • /
    • 2005.10a
    • /
    • pp.725-730
    • /
    • 2005
  • The problem of managing digital design data including drawings, specifications and other technical data in building design and construction units is a real challenge, especially when there is a need to structure the design information across building design companies. The main difficulty in this information management is the shortage of unified rules (or standards) on how the digital design data should be gathered, archived, and preserved in the most efficient way for building design and construction units. The most important issue, which addressed in this work, is the standardized reference of all design data definitions.

  • PDF

Knowledge Transfer between Users and Producers in the Accumulation of Technological Capability

  • Lim, Chai-Sung
    • Journal of Technology Innovation
    • /
    • v.13 no.2
    • /
    • pp.179-205
    • /
    • 2005
  • This study reveals that the user industry has a limited role in being a source of technological capability in the case of the machine tool industry in Korea where the user industry is relatively more advanced than other capital goods industries. This study examines the sources of technological capability in terms of migration of workforces and flow of product development knowledge. Although the capital goods sector is generally regarded as being the sector where user-producer interaction is important, the user industry is not the seed-bed of technological capability for machine development. Users and producers interact in terms of expressing 'needs', mainly in the form of specifications. As a result of receiving unique specifications from users, the producer learns to react by making specific customised special purpose machines. The user's specification could include information o the imported machine originally used. When confronted with technical problems in developing a new machine, the producer accesses foreign sources of knowledge. This study's finding reveals that users of special purpose machines have a significantly clearer role in providing specifications than do users of general purpose machine tools. Most intensive interactive learning between users and producers in the production process is found in special purpose machine tools. From the empirical findings, policy implications are discussed.

  • PDF

An Energy-Efficient MAC Protocol for Wireless Wearable Computer Systems

  • Beh, Jounghoon;Hur, Kyeong;Kim, Wooil;Joo, Yang-Ick
    • Journal of information and communication convergence engineering
    • /
    • v.11 no.1
    • /
    • pp.7-11
    • /
    • 2013
  • Wearable computer systems use the wireless universal serial bus (WUSB), which refers to USB technology that is merged with WiMedia physical layer and medium access control layer (PHY/MAC) technical specifications. WUSB can be applied to wireless personal area network (WPAN) applications as well as wired USB applications such as PAN. WUSB specifications have defined high-speed connections between a WUSB host and WUSB devices for compatibility with USB 2.0 specifications. In this paper, we focus on an integrated system with a WUSB over an IEEE 802.15.6 wireless body area network (WBAN) for wireless wearable computer systems. Due to the portable and wearable nature of wearable computer systems, the WUSB over IEEE 802.15.6 hierarchical medium access control (MAC) protocol has to support power saving operations and integrate WUSB transactions with WBAN traffic efficiently. In this paper, we propose a low-power hibernation technique (LHT) for WUSB over IEEE 802.15.6 hierarchical MAC to improve its energy efficiency. Simulation results show that the LHT also integrates WUSB transactions and WBAN traffic efficiently while it achieves high energy efficiency.

Priority-Based Dynamic Intent Assignment Method in Wi-Fi Direct Environments (Wi-Fi Direct 환경에서 우선순위 기반의 동적 Intent 할당 방안)

  • Lee, Jae-ho
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.41 no.5
    • /
    • pp.565-573
    • /
    • 2016
  • Wi-Fi Direct standard technology(Wi-Fi Peer to Peer Technical Specifications v1.2, 2010) was designed for allowing peer to peer communication between two or more devices and various products which have been currently manufactured such as smart phone and smart TV have already provided this technical function. In this technology the role of Coordinator in Wi-Fi infrastructure would be matched to GO(Group Owner) which needs relatively high energy resource and computation power due to the high probability for allowing 3rd-party connection, however, the current standard specification would be limited in terms of energy distribution because it has not included a process to determine the role of GO. To address above problem, this paper classified considerable parameters into the general parameters for the physicality of devices and the specific parameters for considering the role position depending on use-case scenario, and proposed a new method called DIVA to help efficiently determining GO role from the member devices of Wi-Fi Direct network. Furthermore the effect of this mechanism was proved via simulation-based experiments.