• Title/Summary/Keyword: C language

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A new authentication and message encryption algorithm for roaming user in GSM network

  • Kim, Bum-Sik;Shin, In-Chul
    • Proceedings of the IEEK Conference
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    • 2000.07b
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    • pp.961-964
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    • 2000
  • With the advance of wireless communications technology, mobile communications has become more convenient than ever. However because of the openness of wireless communications, how to protect the privacy between communicating parties is becoming a very important issue. In this paper an authentication and encryption algorithm of the GSM network for roaming user is proposed. In the proposed algorithms, we use a new hash function for user authentication and LFSR (Linear Feedback Shift Register) based stream cipher for message encryption and decryption. Each algorithm is programmed with C language and simulated on IBM-PC system and we analyze the randomness properties of the developed algorithm using statistical analysis.

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Design of a Position Controller for Two Axis Servo System (2축 서보시스템을 위한 위치제어장치 설계)

  • Chang, Seok-Ho;Kim, Gi-Taek;Kim, Hyoung-Joong
    • Journal of Industrial Technology
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    • v.11
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    • pp.115-124
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    • 1991
  • In this study, we design a position controller for two axis servo system. The position controller performs numerical control(NC)to DC or AC servo motor or step motor, and also has a digital input/output sequence capability. The control program composed of position and sequence command, which is called channel, is programmed easily and user-interactively. And it is interpreted and the straight line and arc position command is interpolated. We develop the Z80 microprocessor based system and the software with assembly and C language, and also PC based graphic simulator for the debugging and educational purposes.

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An Experimental Study on the Lengths of English Diphthongs

  • Park, Hee-Suk
    • Speech Sciences
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    • v.8 no.3
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    • pp.7-14
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    • 2001
  • This study was done to find out the difference in vowel length between the English language produced by American soldiers and KATUSA soldiers. Though English pronunciation by Koreans shows different features in many ways, I focused on English vowel length of KATUSA soldiers. I wanted to know if KATUSA soldiers, when compared with American soldiers, showed a foreign accent when they produced English diphthongs. The reason I wanted to deal with English diphthongs is that most Koreans have difficulty in pronouncing them since they do not understand the concept of diphthongs. Therefore I selected five English diphthongs, /aI/, cI/, /au/, /eI/, /ou,/as/ the experimental object, and I tried to find out the foreign accent of them. In this study I also tried to find out the vowel lengths in relation to their utterance positions. I investigated the difference of the English diphthong length between American and KATUSA soldiers using information gathered from experimental results.

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In-service Education Needs Analysis of secondary school Teachers in Busan City (부산지역 중등교사의 현직교육 요구 분석)

  • Chang, Han-Kee
    • Journal of Fisheries and Marine Sciences Education
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    • v.17 no.3
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    • pp.305-323
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    • 2005
  • To reveal secondary teachers' in-service education needs, in-depth interviews were conducted with 15 individual teachers based on semi-structured questions and qualitative data analysis procedures were adopted. They wanted to have; a. more knowledge of one's subject, subject related information, culture and common sense, counseling psychology, foreign language, and the 7th curriculum, b. better skills of student-centered teaching-learning methods, guidance and class management, good use of computers, and educational evaluation, c. improved attitudes regarding democratic problem solution processes, conversation with and service to students from their viewpoints, commitment to preparations for teaching, educational innovation and improvement, elimination of improperness, and pride of teaching job.

Armed Vehicle BAttle Group Simulation : BAGSim (기갑 전투그룹 교전 시뮬레이션 모델)

  • 최상영
    • Journal of the Korea Society for Simulation
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    • v.12 no.1
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    • pp.73-83
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    • 2003
  • This paper presents armed vehicle BAttle Group Simulation model(called BAGSim) which is an object-oriented simulation system for representing battle group engagement consisting of tanks and helicopters. BAGSim is designed in the evolutionary software life cycle approach with the Unified Software Development Process, and implemented with C++ language. BAGSim consists of a preprocessor for engagement scenario definition and simulation data set up, a main processor for triggering engagement event and advancing simulation clock, and a post processor to record simulation histories. Application scenario covers several type of engagement among command tanks, fight tanks, scout helicopters, attack helicopters, anti-tank guided missiles, and decoys. Thus, BAGSim can be effectively used as an analytic tool to examine some operational concepts and tactics, further experimentally fine tune tank design options.

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Infrared Image Enhancement Using A Histogram Partition Stretching and Shrinking Method (히스토그램 분할 펼침과 축소 방법을 이용한 적외선 영상 개선)

  • Jung, Min Chul
    • Journal of the Semiconductor & Display Technology
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    • v.14 no.4
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    • pp.50-55
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    • 2015
  • This paper proposes a new histogram partition stretching and shrinking method for infrared image enhancement. The proposed method divides the histogram of an input image into three partitions according to its mean value and standard deviation. The method stretches both the dark partition and the bright partition of the histogram, while it shrinks the medium partition. As the result, both the dark part and the bright part of the image have more brightness levels. The proposed method is implemented using C language in an embedded Linux system for a high-speed real-time image processing. Experiments were conducted by using various infrared images. The results show that the proposed algorithm is successful for the infrared image enhancement.

Development of Look Ahead Interpolation Algorithm For PC Based CNC System (PC기반CNC시스템을 위한 Look Ahead 보간 알고리즘 개발)

  • Ryu, Sun-Joong
    • Journal of the Semiconductor & Display Technology
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    • v.14 no.4
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    • pp.30-37
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    • 2015
  • This research aims to develop Look Ahead position interpolation algorithm for small size CNC machine controlled by PC based controller. Look Ahead scheme can process a bundle of CNC's linear interpolation commands simultaneously, which reduces acceleration and deceleration time within single linear interpolation command. The algorithm is derived as simple analytical form which can be adapted to PC based CNC system by C language programming. The performance of the algorithm was verified by tail stock machining G codes experimentally. The average traverse speed of the CNC machine was increased by 27.5% and the total traverse time also reduced by 27.2% with the Look Ahead scheme.

Color Segmentation of Vehicle License Plates in the RGB Color Space Using Color Component Binarization (RGB 색상 공간에서 색상 성분 이진화를 이용한차량 번호판 색상 분할)

  • Jung, Min Chul
    • Journal of the Semiconductor & Display Technology
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    • v.13 no.4
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    • pp.49-54
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    • 2014
  • This paper proposes a new color segmentation method of vehicle license plates in the RGB color space. Firstly, the proposed method shifts the histogram of an input image rightwards and then stretches the image of the histogram slide. Secondly, the method separates each of the three RGB color components and performs the adaptive threshold processing with the three components, respectively. Finally, it combines the three components under the condition of making up a segment color and removes noises with the morphological processing. The proposed method is implemented using C language in an embedded Linux system for a high-speed real-time image processing. Experiments were conducted by using real vehicle images. The results show that the proposed algorithm is successful for most vehicle images. However, the method fails in some vehicles when the body and the license plate have the same color.

Development of Control Algorithm and Real Time Numerical Simulation Program for Adaptive Cruise Control Vehicles (적응순향 제어(ACC) 차량의 제어 알고리즘 및 실시간 수치실험 프로그램 개발)

  • 원문철;강연준;강병배
    • Transactions of the Korean Society of Automotive Engineers
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    • v.7 no.7
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    • pp.202-213
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    • 1999
  • Adaptive Cruise Control (ACC) is one of key features on intelligent Transportation System(ITS). In ACC, the steering is done by a driver, but the engine throttle valve and the brake are controlled electronically. The relative velocity and distance from the preceeding vehicle are measured by radars or image processing units and relevant vehicular spacing is maintained in ACC control systems. In this study, vehicle longitudinal dynamics are modeled to simulate vehicle longitudinal maneuver and to design longtitudinal controllers for ACC vehicles. The control algorithm is designed based on the modeled vehicle longitudinal dynamics using a non-linear sliding mode control method. To verity the performance of the control algorithm, a real time numerical simulation program is developed on a Silicon Graphics workstation using C-language . A real time graphic program is alos develpe and integrated with the numerical simulation program.

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Application Scheme of PostgreSQL-PostGIS Server Engine based on Open Source for GIS Portal Building (GIS 포털 구축을 위한 공개 소스 기반 PostgreSQL-PostGIS 서버 엔진의 응용 설계)

  • Han, Sun-Mook;Lee, Ki-Won
    • Proceedings of the KSRS Conference
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    • 2009.03a
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    • pp.134-138
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    • 2009
  • 최근 GIS 포털에 대한 수요자 요구 사항이 증가하고 있고 기존의 웹 GIS 응용 프로그램 개발 기법과의 연계와 통합이 중요한 연구 주제로 부각되고 있다. 본 연구에서는 공개 소스인 PostgreSQL - PostGIS를 이용하여 GIS 포털 구축을 위한 응용 설계 연구를 수행하였다. PostgreSQL를 데이터베이스 시스템으로 하여 공간 질의 및 분석 기능 등 GIS 기능을 연동시키는 PostGIS는 서버 GIS 엔진으로 점점 활용 가치가 증가하고 있으나 GIS 포털에서 이를 적용한 사례는 현재까지 보고된 바가 거의 없다. 본 응용 설계는 전체 시스템 설계 보다는 주로 포털에서의 인터페이스 부분을 주로 다루고자 하며 시험 구현 프로그램의 라이브러리는 PostGIS의 C Language Interface(LIBPQ)와 OGC library를 이용하여 공간 데이터에 대한 기본 기능을 구현하였다. 본 연구를 통하여 구글, 다음, 네이버 등과 같은 일반 검색 엔진에서 경쟁적으로 제공하는 웹 맵핑 수준에서 위성영상정보와 지도정보 서비스가 보다 체계적으로 웹 GIS 기술과 연계될 수 있는 기반을 마련하고자 한다.

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