• 제목/요약/키워드: science and technology system

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인터넷 웹 기반 환경에서의 원격 제어 시스템 (Internet Web-Based Remote Control System Using SNMP)

  • 최주엽;오영은;전호석;송중호;최익
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 G
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    • pp.3159-3161
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    • 1999
  • This paper aims at developing remote control system to control and monitor distributed various devices through internet or information communication network. SNMP (Simple Network Management Protocol) and UPS (Uninterruptible Power Supply) are adopted for network management protocol and applied device, respectively. For controlling and monitoring distributed devices in real-time, Java-environment software is constructed. Also, general-use interface controller between network device and applied device is proposed. Finally, serial communication such as RS-232 and RS-485 is used between controller and applied device.

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Genetic Characterization of Two Putative Toxin-Antitoxin Systems on Cryptic Plasm ids from Bacillus thuringiensis Strain YBT-1520

  • Liu, Xiaojin;Zhu, Shufang;Ye, Weixing;Ruan, Lifang;Yu, Ziniu;Zhao, Changming;Sun, Ming
    • Journal of Microbiology and Biotechnology
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    • 제18권10호
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    • pp.1630-1633
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    • 2008
  • A novel putative toxin-antitoxin segregational stability system named KyAB system was identified in a novel native plasmid pBMB8240 from Bacillus thuringiensis strain YBT-1520, based on sequences homology with other toxin-antitoxin systems, the lethal activity of the KyB putative toxin in Escherichia coli and the stabilizing effect of the kyAB system in Bacillus thuringiensis. Secondarily, the native plasmid pBMB9741 from the same strain was resequenced and the corrected plasmid was named as pBMB7635. Based on sequence homology with the tasAB system and the lethal activity of toxin protein in Escherichia coli, a tasAB-like putative toxin-antitoxin system was identified on pBMB7635.

Design and Validation of Quantum Key Management System for Construction of KREONET Quantum Cryptography Communication

  • Kyu-Seok Shim;Yong-hwan Kim;Ilkwon Sohn;Eunjoo Lee;Kwang-il Bae;Wonhyuk Lee
    • Journal of Web Engineering
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    • 제21권5호
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    • pp.1377-1418
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    • 2022
  • As it has been recently proven that the public key-based RSA algorithms that are currently used in encryption can be unlocked by Shor's algorithm of quantum computers in a short time, conventional security systems are facing new threats, and accordingly, studies have been actively conducted on new security systems. They are classified into two typical methods: Post Quantum Cryptography (PQC) and Quantum Key Distribution (QKD). PQC aims to design conventional cryptography systems in a more robust way so that they will not be decrypted by a quantum computer in a short time whereas QKD aims to make data tapping and interception physically impossible by using quantum mechanical characteristics. In this paper, we design a quantum key management system, which is most crucial for constructing a QKD network and analyze the design requirements to apply them to Korea Research Environment Open NETwork (KREONET). The quantum key management system not only manages the lifecycle, such as storage, management, derivation, allocation, and deletion of the symmetric key generated in QKD but also enables many-to-many communication in QKD communication based on the key relay function and P2P communication to overcome the limitation of distance, which is a disadvantage of QKD. We have validated the designed quantum key management system through simulations to supplement the parts that were not considered during the initial design.

Balancing a seesaw with reinforcement learning

  • Tengis, Ts.;Uurtsaikh, L.;Batminkh, A.
    • International Journal of Advanced Culture Technology
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    • 제8권4호
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    • pp.51-57
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    • 2020
  • A propeller-based seesaw system is a system that can represent one of axis of four propeller drones and its stabilization has been replaced by intelligent control system instead of often used control methods such as PID and state space. Today, robots are increasingly use machine learning methods to adapt to their environment and learn to perform the right actions. In this article, we propose a Q-learning-based approach to control the stability of a seesaw system with a propeller. From the experimental results that it is possible to fully learn the balance control of a seesaw system by correctly defining the state of the system, the actions to be performed, and the reward functions. Our proposed method solves the seesaw stabilization.

A Noise Re-radiation Calibration Technique in Interferometric Synthetic Aperture Radiometer for Sub-Y-type Array at Ka-Band

  • Seo Seungwon;Kim Sunghyun;Choi Junho;Park Hyuk;Lee Hojin;Kim Yonghoon;Kang Gumsil
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.577-580
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    • 2004
  • To overcome with large size noise source distribution network design difficulty in interferometric radiometer system, especially for sub-Y-type array, a new on-board calibration technique using noise re-radiation is proposed in this paper. The suggested calibration technique is using noise re-radiation effect of center antenna after noise source injection from matched load. This approach is especially proper to sub-Y-type array interferometric synthetic aperture radiometer in mm-wave frequency band. Compared with noise injection network of a conventional synthetic aperture radiometer, the system mass, volume, and hardware complexity is reduced and cost-effective. Only one internal noise source, matched load, is used for injection using noise re-radiation technique a small set of sub-Y receiver channels is calibrated. Detailed calibration scenario is discussed and simulation results about noise re­radiation effect are presented.

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Development of the Pulsed Plasma Thruster (PPT) for Science and Technology Satellite-2 (STSAT-2)

  • Shin, G.H.;Nam, M.R.;Cha, W.H.;Lim, J.T.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.352-355
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    • 2005
  • This paper describes an engineering model development of a pulsed plasma thruster, which is capable of an impulse bit of 20uNs and a specific impulse of 800s. The solid fuel which is Teflon allows for a self-contained, inert and stable propellant system. And, the PPT technology makes it possible to consider a revolutionary attitude control system (ACS) concept providing stabilization and pointing accuracies previously obtainable only with reaction wheels, with reduced mass and power requirements.

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SYN Flood DoS Detection System Using Time Dependent Finite Automata

  • Noura AlDossary;Sarah AlQahtani;Reem Alzaher;Atta-ur-Rahman
    • International Journal of Computer Science & Network Security
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    • 제23권6호
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    • pp.147-154
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    • 2023
  • Network intrusion refers to any unauthorized penetration or activity on a computer network. This upsets the confidentiality, integrity, and availability of the network system. One of the major threats to any system's availability is a Denial-of-Service (DoS) attack, which is intended to deny a legitimate user access to resources. Therefore, due to the complexity of DoS attacks, it is increasingly important to abstract and describe these attacks in a way that will be effectively detected. The automaton theory is used in this paper to implement a SYN Flood detection system based on Time-Dependent Finite Automata (TDFA).

Forecasting Korean National Innovation System and Science & Technology Policy after the COVID-19

  • Park, Sung-Uk;Kwon, Ki-Seok
    • Asian Journal of Innovation and Policy
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    • 제9권2호
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    • pp.145-163
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    • 2020
  • The COVID-19 is a pandemic that affects all facets of our life and will change many patterns in science technology and innovation. A qualitative study was conducted using Focus Group Interview involving ten industry-academia-research experts with the objective of identifying changes in Korea's national innovation system and science & technology policy after the COVID-19. Eight questions were designed, based on the major components of the national innovation system, such as companies, universities, and research institutes, to discuss the changes in the national innovation system and science & technology policy. Also, keyword analysis and cluster analysis were performed using the network analysis program VOSviewer. It is predicted that, in the wake of the COVID-19, Korea's national innovation system will shift to a new paradigm that is more decentralized, responsive, and autonomous. Furthermore, several policy agendas that can turn these changes into positive momentum of change in science & technology policy are presented.

반도체 광 증폭기를 이용한 전광 데이터 추출 (All-optical Data Extraction Based on Optical Logic Gates)

  • 이지석;정미;이혁재;이택진;전영민;이석;우덕하;이주한;김재헌
    • 한국광학회지
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    • 제23권4호
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    • pp.143-146
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    • 2012
  • 본 논문에서는 반도체 광 증폭기(Semiconductor Optical Amplifier)의 교차 진폭 변조 현상을 이용하여 광 컴퓨팅이나 광통신에서 데이터의 패킷 교환, 데이터 리셋 혹은 추가나 제거에 필수적인 전광 데이터 추출을 시뮬레이션하고 실험적으로 구현하였다. 전광 데이터 추출의 실험적 시뮬레이션에는 상용 프로그램인 VPI Tool을 사용하였으며 기본적으로 두 개의 반도체 광 증폭기(SOA)를 사용하여 AND 논리를 구성한 후 이를 이용하여 데이터를 추출하였다. 또한 높은 집적성과 효율로 고속으로 연산할 수 있는 가능성을 확인하였다.

Design of Wireless Power Transfer System for Railway Application

  • Hwang, Kiwon;Kim, Seonghwan;Kim, Seongkyu;Chun, Yangbae;Ahn, Seungyoung
    • International Journal of Railway
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    • 제5권4호
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    • pp.167-174
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    • 2012
  • As wireless power transfer (WPT) technologies emerge in a wide range of applications including public transportation, many expect that applying the technology to the current railway systems will bring positive effects to current railway systems. In this paper, we introduce design methodology of a WPT system for railway application. Fundamental principles of magnetic fields and a WPT circuit are first analyzed, and advantages and efficiency of a possible train system are discussed. It then examines other significant factors such as performance requirements and EMC criteria to design a wireless train system.