• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2380-2382
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• 2004

In this paper, Web server is built up using PXA255, 32bit RISC processor with porting Embedded Linux and GoAhead, HTTP(Hyper Text Transfer Protocol) web server, and the system with can monitor and control the environment and condition for AICC(Automatic Intelligent Cruise Control) is realized. For sending the operation condition and change of vehicle the desired data is derived by interacting ECU(Electric Control Unit) and Embedded system and the rpm of engine is controlled by step motor connected to throttle value.

• IEMEK Journal of Embedded Systems and Applications
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• v.5 no.4
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• pp.243-253
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• 2010

Multihop data delivery in vehicular ad hoc networks (VANETs) suffers from the fact that vehicles are highly mobile and inter-vehicle links are frequently disconnected. In such networks, for efficient multihop routing of road safety information (e.g. road accident and emergency message) to the area of interest, reliable communication and fast delivery with minimum delay are mandatory. In this paper, we propose a multihop vehicle-to-infrastructure routing protocol named Vertex-Based Predictive Greedy Routing (VPGR), which predicts a sequence of valid vertices (or junctions) from a source vehicle to fixed infrastructure (or a roadside unit) in the area of interest and, then, forwards data to the fixed infrastructure through the sequence of vertices in urban environments. The well known predictive directional greedy routing mechanism is used for data forwarding phase in VPGR. The proposed VPGR leverages the geographic position, velocity, direction and acceleration of vehicles for both the calculation of a sequence of valid vertices and the predictive directional greedy routing. Simulation results show significant performance improvement compared to conventional routing protocols in terms of packet delivery ratio, end-to-end delay and routing overhead.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.1
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• pp.37-45
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• 2015

These days many systems use the gps signal to get their own position. Because it's cheap and accurate and convenient. But, the strength of gps signal is very weak and can be easily interrupted by GPS jamming and GPS spoofing. Normally, fighter can use DME, TACAN, etc to correct their position error when GPS is not working. But, many aircraft which does not have those kinds of hardware need to pay additional cost to get it. In this paper, we propose how to overcome GPS jamming and GPS spoofing by only using data link system. The main purpose of this paper is to make the data link protocol to get an exact position information of own unit at gps error environment.

• The Journal of the Korea institute of electronic communication sciences
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• v.4 no.3
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• pp.230-235
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• 2009

The TMO may contain two types of methods, time-triggered methods(also called the spontaneous methods of SpMs) which are clearly separated from the conventional service methods (SvMs). The SpM executions are triggered upon design time whereas the SvM executions are triggered by service request message from clients. In this paper, we describes the application environment as the patient monitor telemedicine system with TMO structure. Vital sign information web viewer systems is also the standard protocol for medical image and transfer. We have to design to obtain useful vital sign information, which is generated at parsing data receiver modulor of HIS with TMO structure, that is offered by the central monitor of ICU. In order to embrace new technologies as telemedicine service, it is important to develope the standard protocol between different systems in the hospital, as well as the communication with external hospital systems.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.5
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• pp.649-657
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• 2018

It is essential that weapons which are mounted on aircraft need to prove its reliability and safety during its developments. A guided missile should have high reliability and safety throughout various tests which are including ground tests, captive flight tests, detailed technical tests and operational tests. In these various tests, it is vital that software of each component in the guided missile should be easily updated in order to correct algorithms or errors. In this paper, we propose a software update technique based on MDTP(mass data transfer protocol) which are defined in MIL-STD-1760. The proposed techniques have the following advantages: First, software of each unit in a weapon can be updated through a test equipment without disassemble a guided missile. Second, development periods for a software update can be reduced by reusing MDTP. Third, we can easily maintenance of the software because it is based on standard. We proved its efficiency and validity through experiments. Therefore, the proposed technique should be effectively utilized for software update of a weapon mounted on an aircraft during development processes.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.10
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• pp.1990-1998
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• 2017

The success of naval operation prioritizes the implementation of a robust communication network that delivers accurate and prompt communications to one another. The satellite, which is the main communication network of the military, is required to construct a preliminary communication network because of the enemy radio disturbance and weak point of fixed antenna. The military operational communication network has been in transition from voice-centered wireless communication network to text message-based communication network. In this paper we suggest an enhanced communication method built on Roll Call, the main communication method of ROK Navy operating tactical data link called Link-11. Simulation results display that the proposed method reduces the transmission time per unit frame by 4.3 times compared to the Roll Call and 6.3 times compared with the Round Robin & Broadcasting; it is also proved that the higher the direct reception rate, the shorter the transmission time required by 1.6 times maximum.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.8
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• pp.1613-1621
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• 2015

This paper analyzes the rate adaptation scheme and suggests applicable strategy of the MCS(Modulation and Coding Scheme) for improving DCF throughput in the IEEE 802.11ad and 802.11ad wireless LAN. IEEE 802.11ac and 802.11ad wireless LAN provide MCS technique that dynamically adjusts modulation level and code rate to the time-varying channel conditions in order to obtain considerably high data rates. But these standards did not provide rate adaptation algorithm, so this paper surveyes rate adaptation algorithm and suggests MCS scheme applied to IEEE 802.11ac and 802.11ad wireless LAN. Specially A MAC(Medium Access Control) layer throughput is evaluated over error-prone channel in the IEEE 802.11ac-based wireless LAN. In this evaluation, DCF (Distributed Coordination Function) protocol and A-MPDU (MAC Protocol Data Unit Aggregation) scheme are used. Using theoretical analysis method, the MAC saturation throughput is evaluated with the PER (Packet Error Rate) on the condition that the number of station, transmission probability, the number of parallel beams and the number of frames in each A-MPDU are variables.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.989-995
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• 2017

Distributed Control System (DCS) communication networks, which use Fast Ethernet with redundant networks for the transmission of information, have been installed in digitalized nuclear power plants. Normally, failover tests are performed to verify the reliability of redundant networks during design and manufacturing phases; however, systematic integrity tests of DCS networks cannot be fully performed during these phases because all relevant equipment is not installed completely during these two phases. In additions, practical verification tests are insufficient, and there is a need to test the actual failover function of DCS redundant networks in the target environment. The purpose of this study is to verify that the failover functions works correctly in certain abnormal conditions during installation and commissioning phase and identify the influence of network failover on the entire DCS. To quantify the effects of network failover in the DCS, the packets (Protocol Data Units) must be collected and resource usage of the system has to be monitored and analyzed. This study introduces the use of a new methodology for verification of DCS network failover during the installation and commissioning phases. This study is expected to provide insight into verification methodology and the failover effects from DCS redundant networks. It also provides test results of network performance from DCS network failover in digitalized domestic nuclear power plants (NPPs).

• The Journal of Korean Medicine
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• v.38 no.1
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• pp.56-71
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• 2017

Objectives: The purpose of this study was to review the article using an IMU(Inertial Measurement Unit) for measuring the cervical range of motion and to evaluate the feasibility of using an IMU for measuring the cervical range of motion. Method: Scopus was used to search for the articles relating to the inclusion criteria. Which is measuring the cervical range of motion using an IMU. A total of 15 articles were selected through discussion. Degree and the reliability of the cervical range of motion and the validity of the data within the articles were extracted. Results: The measurement of the cervical range of motion using an IMU were $92.25^{\circ}$ to $138.2^{\circ}$, $122.4^{\circ}$ to $154.9^{\circ}$, $73.75^{\circ}$ to $93.1^{\circ}$ on the sagittal plane, transverse plane, and coronal plane respectively. 38 of the 43 values showed good reliability. They were larger than 0.75. 5 of the 43 values showed reliability less than 0.75. They were measured by smart phone. 16 of the 21 values showed good validity. The remaining 5 were measured by smart phone. The lower reliability and validity of smart phone were related to the protocol. The IMU can measure the coupling motion and may be used in various situations. Conclusion: The IMU may become a gold standard for measuring the cervical range of motion. The IMU measured not only the cervical range of motion but also the coupling motion. Furthermore, IMU may be used in various situations. Therefore, IMU must be considered a valuable measurement device.

• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.1
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• pp.53-59
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• 2007

Wimedia UWB(Ultra-Wideband) platform provides data rates up to 480Mbps in WPAN (Wireless Personal Area Network). Wimedia conformant devices access to the channels through superframe concept for communications. As the channel resource is limited, the optimal channel time required for each device needs to be estimated to share the resource efficiently among the devices. In this paper, we propose a scheme to estimate the required channel time in a super frame to satisfy the QoS of the application on a device. The channel time is estimated from the service rate which is computed from the TSPEC of the application. In the process of the estimation, we take the frame overhead for data transmission as well as the overhead due to the acknowledgement scheme, preamble, and MDSU size into consideration. We also analyze and compare the throughputs for different acknowledgement scheme, preamble, and MDSU size situations. The estimated channel time required for a given service rate is allocated in the unit of MAS(Medium Access Slot).