• Title/Summary/Keyword: 2 order system

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Dynamic Modeling Scheme for Control of the Ramjet Propulsion Systems(I) (램제트 추진 시스템의 동적 제어 모델링 기법(I))

  • Kim, Sun-Kyeong;Yeom, Hyo-Won;Jeon, Chang-Soo;Sung, Hong-Gye;Park, Ik-Soo;Lee, Kyu-Joon
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.05a
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    • pp.295-298
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    • 2008
  • In this paper, prototype dynamic modeling scheme to control ramjet propulsion systems were proposed. From the physical understandings of engine system, a typical 2nd-order system model was applied to simulate the dynamic characteristics of fuel supply system. The shock location varience in diffuser to chamber pressure fluctuation is calculated so that the out of phase between two signals was observed.

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Deep Learning-based Tourism Recommendation System using Social Network Analysis

  • Jeong, Chi-Seo;Ryu, Ki-Hwan;Lee, Jong-Yong;Jung, Kye-Dong
    • International Journal of Internet, Broadcasting and Communication
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    • v.12 no.2
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    • pp.113-119
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    • 2020
  • Numerous tourist-related data produced on the Internet contain not only simple tourist information but also diverse ideas and opinions from users. In order to derive meaningful information about tourist sites from such big data, the social network analysis of tourist keywords can identify the frequency of keywords and the relationship between keywords. Thus, it is possible to make recommendations more suitable for users by utilizing the clear recommendation criteria of tourist attractions and the relationship between tourist attractions. In this paper, a recommendation system was designed based on tourist site information through big data social network analysis. Based on user personality information, the types of tourism suitable for users are classified through deep learning and the network analysis among tourist keywords is conducted to identify the relationship between tourist attractions belonging to the type of tourism. Tour information for related tourist attractions shown on SNS and blogs will be recommended through tagging.

A Robust Image Watermarking Algorithm and System Architecture for Semi-fingerprinting (Semi-fingerprinting을 위한 강인한 이미지 워터마킹 알고리즘 및 시스템 구조)

  • Joung, Gil-Ho;Lee, Han-Ho;Eom, Young-Ik
    • The KIPS Transactions:PartD
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    • v.10D no.2
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    • pp.309-316
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    • 2003
  • In this paper, we propose a new watermarking method based on spread spectrum and a semi-fingerprinting system architecture that can be built using our robust watermarking method. Especially, we describe a method that extends the application area of watermarking technology to more practical application domains by applying the watermarking technology that has been focused mainly on copyright protection to fingerprinting area. Our proposed watermarking scheme uses the method that inserts more data by using random number shifting method. We improved the reliability of acquired data with 20-bits CRC code and 60-bits inserted information. In addition, we designed the system architecture based on the recommendation of cIDf (content ID forum) in order to apply the system on the semi-fingerprinting area.

Development of Integrated Design System for High Temperature, High Pressure Parts for Chemical Plants (화학플랜트 고온고압부 설계 효율화를 위한 일관시스템 구축)

  • Jeong Dong Gwan
    • Journal of the Korean Institute of Gas
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    • v.2 no.4
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    • pp.1-6
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    • 1998
  • In order to increase design efficiency, it is required to design steam boiler pressure parts systematically considering daily start-stop operation and load variation. The objective of this research is to develope an integrated system for increasing design efficiency of boiler pressure parts. The developed system consists of three program modules: (1) flexibility design module for the header stub considering fatigue life, (2) fatigue limit calculation and life evaluation module for the thick-walled boiler pressure part under cyclic operation using TRD301 code, (3) drawing automation module for the header and drum producing design drawings, welding data and bill of materials.

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Speed Sensorless Control of Switched Reluctance Motor (스위치드 리럭턴스 전동기의 센서리스 속도제어)

  • Shin, Kyoo-Jae;Kwon, Young-Ahn
    • Journal of IKEEE
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    • v.2 no.2 s.3
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    • pp.166-172
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    • 1998
  • Switched reluctance motor(SRM) has the advantages of simple structure, low rotor inertia and high efficiency. However, position sensor is essential in SRM in order to synchronize the phase excitation to the rotor Position. The Position sensors increase the cost of drive system and tend to reduce system reliability. This paper investigates the speed control of sensorless SRM in which the Phase current and change rate are utilized in position decision, and the period of dwell angle is variable for speed control. The proposed system consists of Position decision circuit, speed controller, digital logic commutator, switching angle controller and inverter The performances in the proposed system are verified through the experiment.

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Development of Dual-Arm Anticancer Drug Compounding Robot and Preparation System with Adaptability and High-Speed

  • Nam, Giyoon;Kim, Young Joo;Kim, Yun Jung;Kim, Yeoun Jae;Seo, Jung Ae;Kim, Kyunghwan;Kim, Kwang Gi
    • Journal of International Society for Simulation Surgery
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    • v.3 no.2
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    • pp.64-68
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    • 2016
  • Aim Robots are able to increase safety for pharmacy staff as separating from toxicity of anti-cancer drugs. For patient safety, it would provide right dose of the drugs. Additionally, it can reduce price of the drugs. Therefore, in this study, a novel compounding anticancer drugs robot system (Dupalro) was developed. Methods We used the robot system, Motoman dual-arm robot from YASKAWA, Japan and medications which are adapted for the robot were constructed. In order to develop a process of compounding anticancer drugs, information about five medications that are required to make anticancer drugs in hospitals was used. Results System for the five types of medications was constructed, and relating procedures for anticancer drugs compounding robot were developed. Conclusion Dupalro successfully was able to not only provide incremental safety and efficiency for both patients and pharmacy staff, but also decrease price of anticancer drugs.

A Comparative Analysis of Legal Deposit System for Electronic Publications (국내외 전자출판물 납본제도의 분석)

  • Yoon, Hee-Yoon
    • Journal of the Korean Society for Library and Information Science
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    • v.36 no.2
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    • pp.185-207
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    • 2002
  • Legal deposit system is an important legal instrument for national libraries. But the law or act based on print materials in many countries predates the current information age and requires a new legal framework in order to encompass electronic publications. Many national libraries, therefore, are seeking to encourage their governments to establish legal deposit for publications in the whole range of formats. The purpose of this paper is to analyse a world-wide trends of the legal deposit system for on-line publications as well as off-line materials. The result of this analysis will be used to develop a new model of legal deposit system in Korea.

Design Capacity Evaluation of 2-stage Hot Water Heat Exchanger in Apartment Mechanical Rooms with District Heating System (지역난방 공동주택에 설치하는 급탕 2단 열교환기의 용량 적정성 평가에 관한 연구)

  • Chung, Kwang-Seop;Sa, Ki-Yong;Kim, Lae-Hyun;Lee, Hoon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.21 no.8
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    • pp.456-461
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    • 2009
  • Recently, an increasing interest in district heating system has emerged rapidly, In this paper, the physical measurements and data to be monitoring through the internet were carried out with regard to hot water heating energy consumption at the three apartment housings with district heating system in Sang-am district of Seoul, Korea, Measurements were made of the thermal factors such as the pressure of heating pipe, flow rates, hot water temperature and etc, The objective of this study is to compare the design capacity of reheat exchanger with that of preheat exchanger in order to evaluate for the number of plates of two exchangers to be distributed properly.

Using Field Programmable Gate Array Hardware for the Performance Improvement of Ultrasonic Wave Propagation Imaging System

  • Shan, Jaffry Syed;Abbas, Syed Haider;Kang, Donghoon;Lee, Jungryul
    • Journal of the Korean Society for Nondestructive Testing
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    • v.35 no.6
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    • pp.389-397
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    • 2015
  • Recently, wave propagation imaging based on laser scanning-generated elastic waves has been intensively used for nondestructive inspection. However, the proficiency of the conventional software based system reduces when the scan area is large since the processing time increases significantly due to unavoidable processor multitasking, where computing resources are shared with multiple processes. Hence, the field programmable gate array (FPGA) was introduced for a wave propagation imaging method in order to obtain extreme processing time reduction. An FPGA board was used for the design, implementing post-processing ultrasonic wave propagation imaging (UWPI). The results were compared with the conventional system and considerable improvement was observed, with at least 78% (scanning of $100{\times}100mm^2$ with 0.5 mm interval) to 87.5% (scanning of $200{\times}200mm^2$ with 0.5 mm interval) less processing time, strengthening the claim for the research. This new concept to implement FPGA technology into the UPI system will act as a break-through technology for full-scale automatic inspection.

Construction of a 40-channel SQUID System and Its Application to Neuromagnetic Measurements

  • Lee, Y.H.;Kim, J.M.;Kwon, H.C.;Park, Y.K.;Park, J.C.;Lee, D.H.;Ahn, C.B.
    • Progress in Superconductivity
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    • v.2 no.1
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    • pp.20-26
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    • 2000
  • A 40-channel superconducting quantum interference device (SQUID) system was constructed for measuring neuromagnetic fields. Main features of the system are the use of double relaxation oscillation SQUIDs (DROSs), and planar gradiometers measuring magnetic field components tangential to the head surface. The DROSs with high flux-to-voltage transfers enabled direct readout of the SQUID output by room-temperature dc preamplifiers and simple flux-locked loop circuits could be used for SQUID operation. The pickup coil is an integrated first-order planar gradiometer with a baseline of 40 mm. Average noise level of the 40 channels is around 1.2 $fT/cm/{\surd}Hz$ at 100 Hz, corresponding to a field noise of 5 $fT/{\surd}Hz$, operated inside a magnetically shielded room. The SQUID insert was designed to have low thermal load, minimizing the loss of liquid helium. The constructed system was applied to measure auditory-evoked neuromagnetic fields.

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