• Journal of Advanced Navigation Technology
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• v.24 no.5
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• pp.438-443
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• 2020

To transfer files between nodes on network based on Ethernet, file transfer protocol (FTP) on TCP/IP and trivial file transfer protocol (TFTP) on UDP/IP are mostly used. Due to the lack of resources (processor, memory and so on) in the embedded system where we generally use for simple works with small firmware like ones; many of the systems implement only UDP/IP for their network stacks. Thus, TFTP is greatly to be preferred. For examples, environmental sensor devices for sensor networks, Boot Loader for general embedded device and preboot execution environment (PXE) boot for PC provide the TFTP. The logic of TFTP is simple for file transmission but, there is Stop-And-Wait problem during the process which occurs long blocking time. In this paper, we propose an algorithm which called QuTFTP(Quick UDP Trivial File Transfer Protocol) to reduce the length of the blocking time and to be compatible with the legacy TFTP.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.653-656
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• 2013

TFTP(Trivial File Transfer Protocol)는 UDP(User Datagram Protocol) 기반의 파일 전송 프로토콜이다. TFTP는 프로토콜 구조가 단순하여 작은 크기의 데이터를 빠른 속도로 전송할 때 사용된다. 하지만 TFTP는 보안 기능을 지원하지 않기 때문에 데이터 노출의 위험이 있다. 본 논문에서는 Diffie-Hellman 키 교환 방식과 AES-CBC(Advanced Encryption Standard-Cipher Block Chaining) 암호화 방식을 이용하여 TFTP 프로토콜에 보안 기능을 추가하였다. Diffie-Hellman 키 교환 방식을 이용하여 두 사용자 간에 비밀 키를 공유하도록 하였고, AES-CBC 암호화를 지원하여 기밀성을 제공하도록 하였다. 수신된 데이터는 암호화 과정의 역으로 복호화를 수행하였다. WireShark 프로그램을 통하여 암호화된 데이터가 전송 되는 것을 확인하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.87-87
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• 2010

We report a new patterning technique of inorganic materials by using thin-film transfer printing (TFTP) with atomic layer deposition. This method consists of the atomic layer deposition (ALD) of inorganic thin film and a nanotransfer printing (nTP) that is based on a water-mediated transfer process. In the TFTP method, the Al2O3 ALD growth occurs on FTS-coated PDMS stamp without specific chemical species, such as hydroxyl group. The CF3-terminated alkylsiloxane monolayer, which is coated on PDMS stamp, provides a weak adhesion between the deposited Al2O3 and stamp, and promotes the easy and complete release of Al2O3 film from the stamp. And also, the water layer serves as an adhesion layer to provide good conformal contact and form strong covalent bonding between the Al2O3 layer and Si substrate. Thus, the TFTP technique is potentially useful for making nanochannels of various inorganic materials.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04a
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• pp.403-405
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• 2000

본 논문에서는 대표적인 실시간 운영체제인 VxWorks를 대상으로 인터넷 접속 지원 모듈을 개발하고 기능을 시험하였다. 개발된 인터넷 접속 지원 모듈은 네트워크 라이브러리와 DHCP 클라이언트, TFTP 클라이언트/서버, 텔넷 클라이언트 프로그램으로 구성되어 있으며, VxWorks에서 인터넷 접속을 위한 네트워크 환경 설정과 파일 송/수신, 원격 시스템 접속 기능 등을 제공하고 있다.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10c
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• pp.325-327
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• 2000

본 논문에서는 Embedding OS를 대상으로 한 인터넷 접속 지원 모듈을 개발하고 기능을 시험하였다. 개발된 인터넷 접속 지원 모듈은 PPP 전화접속네트워크와 네트워크 라이브러리, DHCP 클라이언트, TFTP 클라이언트/서버, 텔넷 클라이언트 프로그램으로 구성되어 있으며, Embedded OS에서 인터넷 접속을 위한 네트워크 환경 설정과 파일 송/수신, 원격 시스템 접속 기능 등을 제공하고 있다.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.868-870
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• 2003

In this paper, I have implemented the security system using shell script that periodically checking the security elements of unix system for security it transmit to a monitoring server and monitoring many clients. Agent of client executing by crontab scheduler, Environment of server to receive data use restricted TFTP in SunOS. And then, Because of using shell script, apply shell to system with flexible, control performance, and can meet on a sudden situation.

• Atmosphere
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• v.27 no.2
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• pp.119-131
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• 2017

We present and discuss the Tropopause Folding Turbulence Detection (TFTD) algorithm for the Korean Communication, Ocean, Meteorological Satellite (COMS) which is originally developed for the Tropopause Folding Turbulence Product (TFTP) from the Geostationary Operational Environmental Satellite (GOES)-R. The TFTD algorithm assumes that the tropopause folding is linked to the Clear Air Turbulence (CAT), and thereby the tropopause folding areas are detected from the rapid spatial gradients of the upper tropospheric specific humidity. The Layer Averaged Specific Humidity (LASH) is used to represent the upper tropospheric specific humidity calculated using COMS $6.7{\mu}m$ water vapor channel and ERA-interim reanalysis temperature at 300, 400, and 500 hPa. The comparison of LASH with the numerical model specific humidity shows a strong negative correlation of 80% or more. We apply the single threshold, which is determined from sensitivity analysis, for cloud-clearing to overcome strong gradient of LASH at the edge of clouds. The tropopause break lines are detected from the location of strong LASH-gradient using the Canny edge detection based on the image processing technique. The tropopause folding area is defined by expanding the break lines by 2-degree positive gradient direction. The validations of COMS TFTD is performed with Pilot Reports (PIREPs) filtered out Convective Induced Turbulence (CIT) from Dec 2013 to Nov 2014 over the South Korea. The score test shows 0.49 PODy (Probability of Detection 'Yes') and 0.64 PODn (Probability of Detection 'No'). Low POD results from various kinds of CAT reported from PIREPs and the characteristics of high sensitivity in edge detection algorithm.