• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.43 no.6
• /
• pp.540-547
• /
• 2015

This paper describes development contents and flight tests of an ACMI simulator based on LVC integrating architecture. ACMI is the system that provides air combat training and ground bombing training for improving fighting efficiency, that is the live simulation involving real people to operate real systems. ACMI simulator was developed for technic acquisition of LVC interoperability by using data link communication. ACMI simulator simulated maneuvering of a fighter by operating an UAV, a fighter can be distinguished from an UAV by maneuvering characteristics. This study proposes maneuvering simulation method by using flight data of the UAV, and performed its flight test for verifying similarity of fighter maneuvering.

• Journal of radiological science and technology
• /
• v.39 no.3
• /
• pp.323-328
• /
• 2016

The spatial dose distribution was measured with ionization chamber as preliminary study to evaluate operator dose and to study dose reduction during neuro-interventional procedures. The zone of operators was divided into four area (45, 135, 225, and 315 degree).We supposed that operator exist on the four area and indicated location of critical organs(eyes, breast, gonad). The spatial doses were measured depending on distance( 80, 100, 120, and 140 cm) and location of critical organs. The spatial doses of area of 225 degree were 114.5 mR/h (eyes location), 143.1 mR/h (breast location) and 147 mR/h (gonad location) in 80 cm. When changed location of x-ray generator, spatial dose increased in $18.1{\pm}10.5%$, averagely. We certified spatial dose in the operator locations, Using the results of this study, It is feasible to protect operator from radiation in neuro-interventional procedures.

• Journal of Korean Society for Geospatial Information Science
• /
• v.19 no.3
• /
• pp.41-47
• /
• 2011

Processing of the raw LiDAR data requires the high-end processor, because data form is a vector. In contrast, if LiDAR data is converted into a regular grid pattern by filltering, that has advantage of being in a low-cost equipment, because of the simple structure and faster processing speed. Especially, by using grid data classification, such as Quadtree, some of trees and cars are removed, so it has advantage of modeling. Therefore, this study presents the algorithm for automatic extraction of ground points using Quadtree and refion growing method from LiDAR data. In addition, Error analysis was performed based on the 1:5000 digital map of sample area to analyze the classification of ground points. In a result, the ground classification accuracy is over 98%. So it has the advantage of extracting the ground points. In addition, non-ground points, such as cars and tree, are effectively removed as using Quadtree and region growing method.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.43 no.3
• /
• pp.204-212
• /
• 2015

The infrared lock-on range of target aircraft plays a critical role in determining the aircraft survivability. In this investigation, the effects of various UAV engine nozzle configurations on the aircraft lock-on range were theoretically analyzed. A virtual subsonic aircraft was proposed first, based on the mission requirement and the engine performance analysis, and convergent-type nozzles were then designed. After determining thermal flow field and nozzle surface temperature distribution with the CFD code, an additional analysis was conducted to predict the IR signature. Also, atmospheric transmissivity for various latitude and seasons was calculated, using the LOWTRAN code. Finally, the lock-on and lethal envelopes were calculated for different nozzle configurations, assuming the sensor threshold of the given IR guided missile. It was shown that the maximum 55.3% reduction in lock-on range is possible for deformed nozzles with the high aspect ratio.

• Journal of Sensor Science and Technology
• /
• v.12 no.2
• /
• pp.88-94
• /
• 2003

Electromyogram (EMG) is the bioelectric signal induced by motor nerves. Analyzing EMG with the movement produced by muscle contraction, we can provide input commands to a computer as a man-machine interface as well as can evaluate the patient's motional abnormality. In this paper, we developed an integrated miniaturized device which acquires and transmits the surface EMG of an interested muscle. Developed system measures $60{\times}40{\times}25mm$, weighs 100g. Using an amplifier circuitry on the electrodes and the radio frequency transmission, the developed system dispenses with the use of cables among the electrodes, amplifier, and the post processing system (personal computer). The wiring used in conventional systems can be obstacle for natural motion and source of motion artifacts. In results, the developed system improves not only the signal-to-noise ration in dynamic EMG measurement, but also the user convenience. We propose a new human-computer interface as well as a dynamic EMG measurement system as a possible application of the developed system.

• Journal of the Institute of Convergence Signal Processing
• /
• v.8 no.1
• /
• pp.51-57
• /
• 2007

In this paper we introduce the concept of MPLS-based VPN and propose a scheme for providing VPN services in MPLS networks. Furthermore, we design the control components and the operational procedures and evaluated the performance of traditional VPN implementation methods and MPLS-based VPN. In this scheme it is possible to solve several problems that IP-based VPN pertains via the allocation of VPN ID and virtual space without tunneling, thereby providing effective VPN services. In other words, the MPLS-based VPN scheme uses MPLS networking technology together with the PSTN which can achieve a perfect segregation of user traffic on per-customer basis in a physical link and can guarantee high reliability and security levels. Specially, in the perspective of customers, it can save networking facilities installation and maintenance costs considerably. On the contrary, it possesses some shortcomings in that its deployment tends to be restricted within an ISP's network boundary and it is vulnerable to external security break-ins when going through public networks such as the Internet due to its lack of data encryption capability.

• Journal of the Korea Society of Computer and Information
• /
• v.12 no.3
• /
• pp.27-35
• /
• 2007

The majority of farm managers growing the garden products in greenhouse concern massively about the diagnosis and prevention of the breeding and extermination for pests. especially, the managing problem for pests turns up as main issue. In the paper, we first build a wireless sensor network with soil and environment sensors such as illumination, temperature and humidity. And then we design and implement multimedia pest predication and management system which is able to predict and manage various pest of garden products in greenhouse. The proposed system can support the database with information about the pests by building up wireless sensor network in greenhouse compared with existing high-priced PLC device as well as collect various environment information from soil, the interior of greenhouse, and the exterior of greenhouse. To verify the good capability of our system, we implemented several GUI interface corresponding desktop. web, and PDA mobile platform based on real greenhouse model. Finally, we can confirm that our system work well prediction and management of pest of garden products in greenhouse based on several platforms.

• Journal of Navigation and Port Research
• /
• v.34 no.3
• /
• pp.153-160
• /
• 2010

Simulation visualization technology is an important constituent through which users directly interact with simulators. Simulator users have a needs for more fast, realistic and intuitive visualization. Though hardware-related performances such as computing power and visual equipment have been grown, the limits have existed in graphics rendering engines generally used in marine simulator up to now. This paper has focused on the review of graphic rendering engines available for simulation visualization. We had deduced system requirements for visualization of ship handling simulation, had surveyed graphic rendering engines as commercial and open source, and analyzed strengths and weakness of them. The feasibility study for simulation visualization of tug-barge transportation with an open source graphics rendering engine(OGRE3D) has been demonstrated.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.10
• /
• pp.1860-1866
• /
• 2016

Helicopter-related collision accidents with structures mostly occur at landing, especially in a limited visibility environment, which necessitates some secondary equipment like a radar that can generate stationary clutter image. In this paper, we propose an algorithm that makes an image of stationary ground clutter in two dimensional range and azimuth angle domain. We present a mathematical model for the received signals from each clutter patch in the iso range ring and analyze their clutter and Doppler characteristics, assuming that a helicopter-borne radar has a rotational antenna. We propose a filter structure, which suppresses side lobe signal components while extracting a main lobe signal component, and suggest a solution for a problem stemmed from the filtering process. Finally, by conducting a simulation we show the performance of the suggested imaging algorithm on a two dimensional virtual scenario of the topographic clutter.

• The KIPS Transactions:PartC
• /
• v.19C no.2
• /
• pp.149-152
• /
• 2012

In the roaming case, the cost of using the visited network is larger than that of home network. So, if a mobile terminal is connected to the visited network, even though it actually came back to the home network, the user may unduly pay for communication. Such a problem frequently occurs when many networks are overlapped in the same region, as shown in the case of Poland. In this paper, we propose a network search algorithm to support the fast comeback to home network in the roaming environment. In the proposed scheme, which is based on the 3GPP specification, the mobile terminal tries to search the home network by using a database of network information, as fast as possible. For performance evaluation, we construct a virtual testbed with real terminal and network equipment to emulate the service providers in Poland. From the experimental results, we can see that the proposed scheme can reduce the time of comeback to the home network by 3~60 minutes, compared the existing 3GPP scheme.