• Title/Summary/Keyword: communication devices

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A Study on Image Acquisition and Usage Trace Analysis of Stick-PC (Stick-PC의 이미지 수집 및 사용흔적 분석에 대한 연구)

  • Lee, Han Hyoung;Bang, Seung Gyu;Baek, Hyun Woo;Jeong, Doo Won;Lee, Sang Jin
    • KIPS Transactions on Computer and Communication Systems
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    • v.6 no.7
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    • pp.307-314
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    • 2017
  • Stick-PC is small and portable, So it can be used like a desktop if you connect it to a display device such as a monitor or TV anytime and anywhere. Accordingly, Stick-PC can related to various crimes, and various evidence may remain. Stick-PC uses the same Windows version of the operating system as the regular Desktop, the artifacts to be analyzed are the same. However, unlike the Desktop, it can be used as a meaningful information for forensic investigation if it is possible to identify the actual user and trace the usage by finding the traces of peripheral devices before analyzing the system due to the mobility. In this paper, We presents a method of collecting images using Bootable OS, which is one of the image collection methods of Stick-PC. In addition, we show how to analyze the trace of peripheral connection and network connection trace such as Display, Bluetooth through the registry and event log, and suggest the application method from the forensic point of view through experimental scenario.

Hybrid (refrctive/diffractive) lens design for the ultra-compact camera module (초소형 영상 전송 모듈용 DOE(Diffractive optical element)렌즈의 설계 및 평가)

  • Lee, Hwan-Seon;Rim, Cheon-Seog;Jo, jae-Heung;Chang, Soo;Lim, Hyun-Kyu
    • Korean Journal of Optics and Photonics
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    • v.12 no.3
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    • pp.240-249
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    • 2001
  • A high speed ultra-compact lens with a diffractive optical element (DOE) is designed, which can be applied to mobile communication devices such as IMT2000, PDA, notebook computer, etc. The designed hybrid lens has sufficiently high performance of less than f/2.2, compact size of 3.3 mm (1st surf. to image), and wide field angle of more than 30 deg. compared with the specifications of a single lens. By proper choice of the aspheric and DOE surface which has very large negative dispersion, we can correct chromatic and high order aberrations through the optimization technique. From Seidel third order aberration theory and Sweatt modeling, the initial data and surface configurations, that is, the combination condition of the DOE and the aspherical surface are obtained. However, due to the consideration of diffraction efficiency of a DOE, we can choose only four cases as the optimization input, and present the best solution after evaluating and comparing those four cases. On the other hand, we also report dramatic improvement in optical performance by inserting another refractive lens (so-called, field flattener), that keeps the refractive power of an original DOE lens and makes the petzval sum zero in the original DOE lens system. ystem.

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Enhancement of PLED lifetime using thin film passivation with amorphous Mg-Zn-F

  • Kang, Byoung-Ho;Kim, Do-Eok;Kim, Jae-Hyun;Seo, Jun-Seon;Kim, Hak-Rin;Lee, Hyeong-Rag;Kwon, Dae-Hyuk;Kang, Shin-Won
    • Journal of Information Display
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    • v.11 no.1
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    • pp.8-11
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    • 2010
  • In this study, a new thin films passivation technique using Zn with high electronegativity and $MgF_2$, a fluorine material with better optical transmittance than the sealing film materials that have thus far been reported was proposed. Targets with various ratios of $MgF_2$ to Zn (5:5, 4:6 and 3:7) were fabricated to control the amount of Zn in the passivation films. The Mg-Zn-F films were deposited onto the substrates and Zn was located in the gap between the lattices of $MgF_2$ without chemical metathesis in the Mg-Zn-F films. The thickness and optical transmittance of the deposited passivation films were approximately 200 nm and 80%, respectively. It was confirmed via electron dispersive spectroscopy (EDS) analysis that the Zn content of the film that was sputtered using a 4:6 ratio target was 9.84 wt%. The Zn contents of the films made from the 5:5 and 3:7 ratio targets were 2.07 and 5.01 wt%, respectively. The water vapor transmission rate (WVTR) was determined to be $38^{\circ}C$, RH 90-100%. The WVTR of the Mg-Zn-F film that was deposited with a 4:6 ratio target nearly reached the limit of the equipment, $1\times10^{-3}\;gm^2{\cdot}day$. As the Zn portion increased, the packing density also increased, and it was found that the passivation films effectively prevented the permeation by either oxygen or water vapor. To measure the characteristics of gas barrier, the film was applied to the emitting device to evaluate their lifetime. The lifetime of the applied device with passivation was increased to 25 times that of the PLED device, which was non-passivated.

NetFPGA based capsulator Implementation and its performance evaluation for Future Internet OpenFlow Testbed (미래인터넷 OpenFlow 테스트베드 구축을 위한 NetFPGA기반 캡슐레이터 구현 및 성능평가)

  • Choi, Yun-Chul;Min, Seok-Hong;Kim, Byung-Chul;Lee, Jae-Yong;Kim, Dae-Young
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.7
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    • pp.118-127
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    • 2010
  • Current TCP/IP-based Internet architecture has been used for over 30 years, however it will confront with fundamental problems due to new protocol extension limitation since communication environments will change drastically and various user requirements will be emerging in near future. To solve these problems, major countries have started Future Internet researches based on clean slate approach and they will deploy large-scale testbed to experiment and verify new functions. OpenFlow switch technology has been proposed as a new experimental technology for independent protocol that can utilized the legacy network devices and does not interfere with the production Internet traffic. Korea also started Future Internet testbed project called FIRST and OpenFlow switch with NetFPGA card will be used to deploy this testbed. To interconnect distributed testbed using OpenFlow switches, logical tunnel should be established by encapsulating MAC frame inside a unicast IP packet between OpenFlow switches because OpenFlow switches are not directly connected. In this paper, we have implemented a NetFPGA-based that performs MAC in IP tunneling between various OpenFlow switch sites implemented in domestic research network KOREN. The performance evaluation shows that the NetFPGA-based capsulator reveals better performance than the software-based tunneling and it can be utilized as a testbed for experimentation of Future Internet technologies.

2003 Asia Pacific Microwave Conference (2003아시아 태평양 마이크로파 학술회의)

  • 김동일;이혁재;박동철;명로훈;윤상원;조영기;남상욱;윤영중;이해영
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2004.01a
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    • pp.1-226
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    • 2004
  • I. Title APMC'03(2003 Asia Pacific Microwave Conference) II. Objecuve $\bigcirc$Investigation of new trend in the field of microwave engineering $\bigcirc$Establishment of R&D track for wireless and high speed communication III. Scope of investigation $\bigcirc$R&D trend in various microwave engineering areas-Solid state Devices and circuits-Electromagnetic Field Theory-EMI&EMC-Phased & Active Array Antennas-Scattering & Propagation $\bigcirc$Discussions with various technical topics-New research & development topics-Establishment of wireless & high speed communications IV. Results During the conference, very active academic exchange were possible between Korean and foreign microwave engineering scholars. It was also possible to introduce the level and activities of Korean microwave engineering researches to foreign countries. Also, it was good opportunity to contact foreign scholars and researchers for valuable academic discussion using technical paper presentations and inquiries.

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Countinuous k-Nearest Neighbor Query Processing Algorithm for Distributed Grid Scheme (분산 그리드 기법을 위한 연속 k-최근접 질의처리 알고리즘)

  • Kim, Young-Chang;Chang, Jae-Woo
    • Journal of Korea Spatial Information System Society
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    • v.11 no.3
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    • pp.9-18
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    • 2009
  • Recently, due to the advanced technologies of mobile devices and wireless communication, there are many studies on telematics and LBS(location-based service) applications. because moving objects usually move on spatial networks, their locations are updated frequently, leading to the degradation of retrieval performance. To manage the frequent updates of moving objects' locations in an efficient way, a new distributed grid scheme, called DS-GRID (distributed S-GRID), and k-NN(k-nearest neighbor) query processing algorithm was proposed[1]. However, the result of k-NN query processing technique may be invalidated as the location of query and moving objects are changed. Therefore, it is necessary to study on continuous k-NN query processing algorithm. In this paper, we propose both MCE-CKNN and MBP(Monitoring in Border Point)-CKNN algorithmss are S-GRID. The MCE-CKNN algorithm splits a query route into sub-routes based on cell and seproves retrieval performance by processing query in parallel way by. In addition, the MBP-CKNN algorithm stores POIs from the border points of each grid cells and seproves retrieval performance by decreasing the number of accesses to the adjacent cells. Finally, it is shown from the performance analysis that our CKNN algorithms achieves 15-53% better retrieval performance than the Kolahdouzan's algorithm.

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A Study on Development of Voice and SMS Alarm System Based on MODBUS Protocol (MODBUS 프로토콜에서 작동되는 음성 및 SMS 경보 시스템 개발에 관한 연구)

  • Seol, Jun-Soo;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.19 no.3
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    • pp.311-318
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    • 2015
  • This dissertation proposes method for development technology of voice and SMS(Short Message Service) alarming system based on modbus protocol. The proposed technology is composed of the following 3 stages; hardware development based on microprocessor, development of input and output driver for modem, mp3 decoder, making modbus protocol stack. In the stage of hardware development based on microprocessor, we develop hardware which receives alarm from modbus master and transmit sms message, play mp3. In the stage of development of input / ouput device driver such as modem, mp3 decoder, we develop program which control each devices. In the stage of making modbus protocol stack, voice and sms alarm system is made for receiving alarm via modbus protocol. To evaluate performance of proposed technology, we issued alarm to voice and sms alarming system on purpose. As a result, response speed of detecting alarm was 10.7ms, communication distance was 1.2Km, operating temperature was from $-25^{\circ}C$ to $70^{\circ}C$, we confirmed supporting modbus protocol. And we verified that proposed voice and sms alarming system in the thesis has a performance to be used as an industrial building alarming system.

Low-Gate-Count 32-Bit 2/3-Stage Pipelined Processor Design (소면적 32-bit 2/3단 파이프라인 프로세서 설계)

  • Lee, Kwang-Min;Park, Sungkyung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.4
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    • pp.59-67
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    • 2016
  • With the enhancement of built-in communication capabilities in various meters and wearable devices, which implies Internet of things (IoT), the demand of small-area embedded processors has increased. In this paper, we introduce a small-area 32-bit pipelined processor, Juno, which is available in the field of IoT. Juno is an EISC (Extendable Instruction Set Computer) machine and has a 2/3-stage pipeline structure to reduce the data dependency of the pipeline. It has a simple pipeline controller which only controls the program counter (PC) and two pipeline registers. It offers $32{\times}32=64$ multiplication, 64/32=32 division, $32{\times}32+64=64$ MAC (multiply and accumulate) operations together with 32*32=64 Galois field multiplication operation for encryption processing in wireless communications. It provides selective inclusion of these algebraic logic blocks if necessary in order to reduce the area of the overall processor. In this case, the gate count of our integer core amounts to 12k~22k and has a performance of 0.57 DMIPS/MHz and 1.024 Coremark/MHz.

Research on the Emergence of Dominant Design from Technological Competition in the Flat-panel Display Industry (평판 디스플레이 기술경쟁에서 지배적 디자인의 출현에 관한 연구)

  • Yoon, Inhwan;Lee, Heesang
    • Management & Information Systems Review
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    • v.37 no.2
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    • pp.63-85
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    • 2018
  • Electronic displays have developed as instruments that function as windows of information to satisfy the bidirectional needs of electronic device manufacturers and users. The cathode-ray tube (CRT) display once dominated the display industry. Now, the liquid crystal display (LCD) is dominant, and promising displays are competing to become the next-generation display. Displays reflect the characteristics of the information and communication technology (ICT) industries, such as technological changes, innovative features, and competitive dynamics, and have technologically evolved to dominate the industry and market through various ICT devices. This research utilizes a dominant design concept and examines the case of the flat-panel display industry to propose a comprehensive framework, which considers technological, organizational, and environmental characteristics, of the determinants influencing dominance in the technology-intensive ICT industry. The results show that a dominant design in the flat-panel display industry emerges from technological competition among several designs, based on technological characteristics and market acceptance, and dominates the industry and market by various environmental factors. Our results emphasize the difference between generic technologies and the speed of technological innovation and expand the understanding of the emergence of a dominant design. Furthermore, this paper suggests practical implications for establishing a competition strategy and strategic guidance for other ICT industries as well as the display industry.

The Devices for Improvement against the Precedents about unfair Transactions in the Security Industries (경비업계에 있어서의 불공정거래의 사례 개선방안)

  • Kim, Tae-Wan
    • Korean Security Journal
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    • no.11
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    • pp.37-60
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    • 2006
  • The area of security service has been maintaining the high growth curve annually by improving security consciousness from increase of the income and the progress of public services's level by the accomplishment in the info-communication field, recently the demand for unmanned security system is extended form commercial purposes into public offices and individual's houses. In addition to, the possible distance of offering services is scheduled to magnify. At the period when security company's influence has been becoming significant, the injustice transaction is the serious factor which obstructs the development of security companies. Therefore, it is urgent thing to devise counterplans to extirpate injustice transactions. There are the legalistic approaches of the breakthroughs against injustice transactions. One thing is settling the standard of the judgment and the other is renovating the provision of injustice transactions. Utilizing the principles of the fair competitions and importing self-obedience programs within the range of trade actions which is permitted by law, acted as the system approach. Moreover, there are such three things which can achieve mutual balances as establishing the range of the permitted action toward business corporations, applying spontaneously the fair competition principles and introducing the system of standard agreements. Gong further, this can establish order of security service areas and control them. Besides, it is possible for every organizations to make and operate the system appropriately by importing the self-observance system.

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