• The Journal of the Convergence on Culture Technology
• /
• v.10 no.5
• /
• pp.189-193
• /
• 2024

As cyber threats increase in the defense sector, the security of weapon system software is becoming increasingly important. Currently, most of the embedded software installed in domestic weapon systems operates based on foreign real-time operating systems(RTOS) that have no security. As a result, the localization and security enhancement of embedded software for weapon systems have emerged as urgent tasks. This study aims to propose the application and development strategies of secure RTOS for weapon systems. To this end, we examined the technological trends of domestic and foreign RTOS and secure RTOS, and analyzed the problems of current embedded software in weapon systems. The results revealed major issues such as low localization, vulnerability to cyber attacks, difficulty in maintenance, increased costs, and loss of opportunities for accumulating technological capabilities. An investigation of the current status of embedded software applied to existing weapon systems found that embedded SW are in operation across all fields, including maneuver, firepower, protection, command and control, communication, naval vessels, and aircraft. Among them, 99% rely on foreign RTOS such as VxWorks. A review of the core functions and applicability of secure RTOS to weapon systems suggests that it can be applied to key areas requiring real-time performance and security, such as fire control, navigation devices, and flight control in existing and future weapon systems. However, ensuring performance and reliability, securing verification and compatibility, and systematic government support were raised as prerequisites.

• Journal of Power Electronics
• /
• v.5 no.2
• /
• pp.151-159
• /
• 2005

The errors generated from current measurement paths are inevitable, and they can be divided into two categories: offset error and scaling error. The current data including these errors cause periodic speed ripples which are one and two times the stator electrical frequency respectively. Since these undesirable ripples bring about harmful influences to motor driving systems, a compensation algorithm must be introduced to the control algorithm of the motor drive. In this paper, a new compensation algorithm is proposed. The signal of the integrator output of the d-axis current regulator is chosen and processed to compensate for the current measurement errors. Usually the d-axis current command is zero or constant to acquire the maximum torque or unity power factor in the ac drive system, and the output of the d-axis current regulator is nearly zero or constant as well. If the stator currents include the offset and scaling errors, the respective motor speed produces a ripple related to one and two times the stator electrical frequency, and the signal of the integrator output of the d-axis current regulator also produces the ripple as the motor speed does. The compensation of the current measurement errors is easily implemented to smooth the signal of the integrator output of the d-axis current regulator by subtracting the DC offset value or rescaling the gain of the hall sensor. Therefore, the proposed algorithm has several features: the robustness in the variation of the mechanical parameters, the application of the steady and transient state, the ease of implementation, and less computation time. The MATLAB simulation and experimental results are shown in order to verify the validity of the proposed current compensating algorithm.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.16 no.2
• /
• pp.160-168
• /
• 2013

In tactical environment, tactical wireless networks are generally comprised of Tactical MANETs(T-MANETs) or Tactical WMNs(T-WMNs). The most important services in tactical network are voice and low rate data such as command control and situation awareness. These data should be forwarded via multi-hop in tactical wireless networks. Urgent and mission-critical data should be protected in this environment, so QoS(Quality of Service) must be guaranteed for specific type of traffic for satisfying the requirement of a user. In IEEE 802.11s, TDMA-based MAC protocol, MCCA(MCF Controlled Channel Access), has a function of resource reservation. But 802.11s protocol can not guarantee the end-to-end QoS, because it only supports reservation with neighbors. In this paper, we propose the routing protocol, R-HWMP(Reservation-based HWMP) which has the resource reservation to support the end-to-end QoS. The proposed protocol can reserve the channel slots and find optimal path in T-WMNs. We analyzed the performance of the proposed protocol and showed that end-to-end QoS is guaranteed using NS-2 simulation.

• Aerospace Engineering and Technology
• /
• v.13 no.1
• /
• pp.37-43
• /
• 2014

The ground station which operates the LEO satellite performs monitoring state of health of the satellite, sending the commands for the imaging mission of receiving the images during about 10 minutes of contact time. To finish the planned procedure in limited contact time, specific level of autonomy is applied in the satellite and the ground system. For example, the attitude and orbit control logic has high level of autonomy because it must be operated alone for long period without operator intervention. On the other hand, the fault management logic has relatively low level of autonomy because of that failure detection and safing operation are performed on-board, whereas failure identification and recovery are on-ground operation. The level of autonomy of the satellite affects also the ground operation. The command set for mission operation is generated by ground system. If the satellite has higher level of autonomy, some of operation currently done on-ground can be performed on-board, so the ground operation can be simplified. In this paper, we discuss the level of autonomy and propose a concept for improving the level of autonomy of an LEO satellite.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.11 no.2
• /
• pp.55-66
• /
• 2015

In this paper, we design and implement a two-way search algorithm that can provide a customized service through the user with real-time two-way communication using a mobile instant messaging service. Therefore, we design and implement the automative search system which enables delivering message to each user mobile terminal from a plurality of relay mobile terminals by utilizing the mobile instant messenger, not to deliver a message from the main server to the mobile instant messenger user directly. Two-way search system using the mobile instant messenger can be immediately collect the user's response is easy to identify the orientation of each user, and thus can be provided to establish a differentiated service plan. Also, It provides a number of services(text, photos, videos, etc) in real-time information to the user by utilizing the mobile instant messenger service without the need to install a separate application. Experiment results, data processing speed of the category processing way to search for the data of the DB server from a user mobile terminal is about 7.06sec, data processing number per minute is about 13 times. The data processing speed of the instruction processing way is about 3.10sec, data processing number per minute is about 10 times. The data processing speed of the natural language processing way is about 5.13sec, per data processing number per minute is about 7 times. Therefore in category processing way, command processing way and natural language processing way, instruction processing way is the most excellent in aspect of data processing speed, otherwise in aspect of per data processing number per minute, the category processing way is the best method.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.6
• /
• pp.640-645
• /
• 2020

To produce an input device stably using the transparent electromagnetic pattern of an electromagnetic induction method, pattern inspection is required in advance in the production process. Various methods of inspecting the capacitive pattern for hand-touch have been proposed, but it is difficult to find the related technical data for the pattern inspection method of the transparent electromagnetic induction method. In this study, to develop an inspection system for a fused electromagnetic resonance pen sensor with a copper-etched metal mesh pattern, an inspection algorithm and method for measuring the antenna impedance inside the sensor was proposed by measuring only the exposed FPCB connector. The proposed method was configured as a control board consisting of a microprocessor that forms a loop between specific channels according to the command of a computer, a computer-controlled by the Windows program, an LCR meter measuring the impedance between specific channels, and transmitting the measurement results back to the computer. An evaluation of the proposed system and measurements of nine specimens showed that it could detect the defects of the sensor used in the actual product.

• Journal of Drive and Control
• /
• v.17 no.2
• /
• pp.1-8
• /
• 2020

Recently, industrial systems are becoming quicker and lighter to enable the reduction of energy consumption and increase productivity. So the latest systems are more flexible and rapid than the previous systems. But, with this improvement, another problem has emerged, such as the increase in residual vibration when a system is started or stopped. The input shaper is a command generation method that can remove residual vibration. It can provide a solution to the problem of residual vibration in industrial systems. However, it is difficult to generate the input shaper in high order systems, such as a typical industrial system because the input shaper is induced from the system's vibration characteristics. This study focused on the extra insensitivity shaper that can compensate for the system's modeling error such as input dynamics, and the high order's system affection. A genetic algorithm was deployed to adjust a vibration limitation for the extra insensitivity of the input shaper. A plant is a low damping system that includes one zero and a pole. The fitness functions are an error signal of the system's response with normalized frequency variations. Verification of the suggested system is satisfied by comparison between the zero vibration derivative input shaper's response and the suggested one.

• Journal of IKEEE
• /
• v.15 no.1
• /
• pp.15-22
• /
• 2011

In order to performing the joint operation of Korean army efficiently, informations about surveillance, reconnaissance, and situation awareness need to be possessed jointly. In the first development phase (basis type) of the Korean joint tactical data link system (JTDLS-K), essential tactical information and recognized situation are owned among platforms in common by using existing wireless terminals. In the second development phase (completion type) of the JTDLS-K, a JTDLS which can perform network centric warfare (NCW) will be developed in due consideration of technology development of the basis type and common technology maturity degree. This is a joint battlefield system that can show fighting power simultaneous and polysynthetically through providing command and control messages effectively to each platform, which is participating in the joint and combined operations. In this paper, the development of JTDLS-K with a common data processor based on common link integration processing (CLIP) is described. From the test results of the system presented in this paper, it is demonstrated that quadrature phase shift keying (QPSK) signals can be applied to the system.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.4
• /
• pp.97-108
• /
• 2016

In this paper, we consider a cooperative monitoring network, which consists of a large number of UAVs, in order to promptly detect event in a disaster area. A command center may not be able to control each UAV individually due to resource constraints. Therefore, UAVs need to autonomously construct a mobile monitoring network in order to maximize monitoring coverage and to adapt the network formation according to environment changes in the disaster area. To that end, we propose multiple UAVs-based cooperative monitoring schemes that uses virtual forces. In this monitoring scheme, an effective monitoring is enabled by extending monitoring coverage using each UAV's circle movements. The UAVs-based monitoring network can also be splitted or merged in order to increase the monitoring effectiveness. Through simulations, we show that the proposed scheme can effectively monitor a large area and achieve a high event detection ratio.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.39 no.3
• /
• pp.1-9
• /
• 2016

NSS (Navigation satellite system) provides the information for determining the position, velocity and time of users in real time using satellite-networking, and is classified into GNSS (Global NSS) and RNSS (Regional NSS). Although GNSS services for global users, the exactitude of provided information is dissatisfied with the degree required in modern systems such as unmanned system, autonomous navigation system for aircraft, ship and others, air-traffic control system. Especially, due to concern about the monopoly status of the countries operating it, some other countries have already considered establishing RNSS. The RNSS services for users within a specific area, however, it not only gives more precise information than those from GNSS, but also can be operated independently from the NSS of other countries. Thus, for Korean RNSS, this paper suggests the methodology to design the satellite constellation considering the regional features of Korean Peninsula. It intends to determine the orbits and the arrangement of navigation satellites for minimizing PDOP (Position dilution of precision). PGA (Parallel Genetic Algorithm) geared to solve this nonlinear optimization problem is proposed and STK (System tool kit) software is used for simulating their space flight. The PGA is composed of several GAs and iterates the process that they search the solution for a problem during the pre-specified generations, and then mutually exchange the superior solutions investigated by each GA. Numerical experiments were performed with increasing from four to seven satellites for Korean RNSS. When the RNSS was established by seven satellites, the time ratio that PDOP was measured to less than 5 (i.e. better than 'Good' level on the meaning of the PDOP value) was found to 94.3% and PDOP was always kept at 10 or less (i.e. better than 'Moderate' level).