• The KIPS Transactions:PartD
• /
• v.13D no.7 s.110
• /
• pp.901-908
• /
• 2006

With the development of wireless communication techniques and mobile environment we are able to transmit data between mobile systems without restriction of time and space. Recently, researches on the data communication between mobile systems have focused on a small amount of sending out or receiving data and data synchronization at a fixed server and mobile clients in mobile environment. However, two more servers should be able to move mutual independently, information is shared with other systems, and data is synchronized in the special environment like a battlefield situation. Therefore, we propose a data synchronization method between systems moving mutual independently in mobile environment. The proposed method is an optimization solution to data propagation path between servers that considers limited bandwidth and process of data for disconnection communication. In addition, we propose a data reduction method that considers importance and sharing of information in order to reduce data transmission between huge servers. We verified the accuracy of data after accomplishing our data synchronization method by applying it in the real world environment. Additionally, we showed that our method could accomplish data synchronization normally within an allowance tolerance when we considered data propagating delay time by server extension.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.17 no.3
• /
• pp.227-233
• /
• 2011

Korea coastal area is highly potential dangerous zone of marine accident due to frequent ship's encounters. VTS center can't identify ship's information because of beyond VHF range. It is also difficult of us to efficiently manage vessel traffic beyond VTS control area, so that it can't prevent marine accident. Presently, korean government is conducting maritime traffic safety assessment according to enlargement of harbor & development of new port but do not have the system which provide danger of information depending on maritime traffic environment with real time. So it is necessary to develop evaluation index which can assess sea risk through the evaluation of maritime traffic environment. In this paper, on the basis of vessel navigator's risk consciousness, we carried out survey & statistical analysis vessel navigator's subjective risk depending on the LOA, crossing situation($045^{\circ}$, $090^{\circ}$, $135^{\circ}$), overtaking, head-on situation, encountering vessel's side, within or outside harbor, speed with other vessel(ex. same, fast or slow), speed difference with other vessel and distance with other vessel & propose basic expression to develop maritime traffic safety evaluation model. And by using this model, we can confirm that this proposing expression is suitable for domestic maritime traffic environment.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.3
• /
• pp.1337-1345
• /
• 2012

The principle of Effective Based Operation applied to the Korean Theater resulted in measurable effects to win the minimum battle. Based on the finding, this study recommends the effect analysis methodology under the V-C interoperability system to acquire a weapon system. This method is followed as below; to confirm the effect data on the organized weapon system, to set MOE, MOP and effect considering the purpose of the analysis, to apply the appropriate operational concept and scenario on the weapon system, and then the available C Model is after action reviewed, adjusted, and given feedback. The V-C interoperability system enables to perform the real-time combat experiment under the virtual synthesized battlefield circumstances. The defensive battle organization and displacement of the future anti-tank guided weapon system was considered in the modeling process. Scenario was written, which encompasses company-level units and the battalion-level operation. Then the available AWAM was embodied and effect-analyzed, which formed the foundation of SBA.

• Journal of the Korea Society for Simulation
• /
• v.21 no.4
• /
• pp.65-73
• /
• 2012

Due to the development of technology related to a weapon system and the info-communication, the battle system of a warship has to manage many kinds of human intervention tactics according to the complicated battlefield environment. Therefore, many kinds of studies about M&S(Modeling & Simulation) have been carried out recently. The previous M&S system based on an agent, however, has simply used non-flexible(or fixed) tactics. In this paper, we propose an agent modeling methodology which has reinforcement learning function for spontaneous(active) reaction and generation evolution learning Function using Genetic Algorithm for more proper reaction for warship battle. We experiment with virtual 1:1 warship combat simulation on the west sea so as to test validity of our proposed methodology. We consequently show the possibility of both reinforcement and evolution learning in a warship battle.

• Convergence Security Journal
• /
• v.11 no.6
• /
• pp.59-66
• /
• 2011

The representative concept of the future war is NCW. The main point of NCW is that it is connected by networ ks and gathers the battlefield status in real time, managing and controlling it. This is most needed in the navy. Operations of the navy are carried out in wide areas, individually or together. During this process, sharing information between each warship should be essential. Furthermore in the case of the American navy, they see the entire world as the operation area so it is a representative example of NCW. The C4I system of the Korean army is separated a ccording to the difference of each army's tactics and weapon system, being developed and managed differently. The refore there is a problem of interoperability lacking in each system. This paper analyzes the developed C4I system of the American navy to analyze the problems of C4I system of the Korean army, and propose the future direction of its development.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.12B
• /
• pp.719-727
• /
• 2007

The Wireless Mesh Network technology is able to provide an infrastructure for isolated islands, in which it is difficult to install cables or wide area such as battlefield of armed forces. Therefore, Wireless Mesh Network is frequently used to satisfy needs for internet connection and active studies and research on them are in progress However, as a result of increase in number of hops under hop-by-hop communication environment has caused a significant decrease in throughput and an increase in delay. Considering the heavy traffic of real-time data, such as voice or moving pictures to adaptive WMN, in a military environment, it is restricted for remote units to have their Mesh Node to get real-time services. Such phenomenon might cause an issue in fairness. In order to resolve this issue, the Location-based Packet Scheduling Scheme, which can provide an fair QoS to each mesh node that is connected to each echelon's AP and operates based on WRR method that gives a priority to emergency message and control packet. The performance of this scheme is validated.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.41 no.5
• /
• pp.421-426
• /
• 2017

In this study, we propose a method for predicting the mechanical properties of the printed circuit board (PCB) that has transversely isotropic characteristics. Unlike the isotropic material, there is no specific test standard for acquisition of the transversely isotropic properties. In addition, common material test methods are not readily applicable to that type of laminated thin plate. Utilizing the natural frequency obtained by a modal test and the sizing optimization technique provided in $OptiStruct^{(R)}$, the mechanical properties of a PCB were derived to minimize the difference between test and analysis results. In addition, the validity of the predicted mechanical properties was confirmed by the MAC (Modal Assurance Criteria) value of each of the compared mode shapes. This proposed approach is expected to be extended to the structural analysis for the design verification of the top product that includes a PCB.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.12 no.5
• /
• pp.191-196
• /
• 2012

The tactical training system that was applied to wire at open terrain and field is no training accomplishment in conformity with battlefield situation portrayal. Therefore, this paper developed the tactical training and evaluation system for growing fruitfully that is installed as a tactical training monitoring system by USN WMN through controlled sensing interlock for collecting sensing data and guaranteed training equipment status and report training result for serviceability of manager. additionally we implemented controller for managing server of sending and manipulating of being gathered training data by sensor using USN and system as GUI methods. This system is easy for adapting new and improved protocol in order to processing many function of H/W and algorithms which is generated by controlled system is applicable easily.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.10B
• /
• pp.865-875
• /
• 2008

In this paper, we propose a reliable multicast scheme for the tactical wireless ad hoc network where the members share the situation and operation data. Our scheme consists of two phases to guarantee the reliability. During the dissemination phase, we utilizes an epidemic approach similar to gossip-based ad hoc routing. Then the group members interchange the message reception state information periodically so that they are able to recover missing packets from the other members. We evaluate the performance of our scheme through extensive simulations using the network simulator in comparison with other existing reliable multicast schemes in mobile ad hoc network. Our scheme shows higher packet delivery ratio regardless of the mobility and imposes much lower control overhead to the non-group members compared with the existing schemes.

• Bulletin of the Korean Space Science Society
• /
• 2009.10a
• /
• pp.25.5-26
• /
• 2009

인류의 활동 무대가 우주공간으로 확대됨으로써 우주기상에 의한 피해를 최소화 할 수 있는 조치가 요구됨에 따라 우주기상에 대한 감시 및 예 경보 업무가 필요해 졌다. 미국은 이미 우주기상 감시와 예보의 필요성을 인식하고 해양대기청(NOAA), 미 공군(USAF), 항공우주국(NASA), 내무부(DOI), 에너지부(DOE), 과학재단(NSF)이 연합하여 1996년 국가우주기상 프로그램(National Space Weather Program)을 수립.추진하고 있다. 특히 정부연구 기관인 NOAA 산하 우주기상예보센터(Space Weather Prediction Center; SWPC)와 미 공군 기상국(AFWA)은 우주기상 자료 생산, 수집, 자료 센터 운용, 연구 지원 및 예 경보 업무를 공동으로 수행하고 있으며 관련 자료 및 정보의 교환 등 매우 밀접하게 상호협력하고 있다. 최근 정부는 과학기술 7대 중점투자 분야별 중점육성후보기술로서 우주감시체계개발기술을 포함한 국가과학기술기본계획(577전략)을 수립 발표하였으며, 대한민국 공군은 향후 우주군 창설을 목표로 우주전력 기반체계구축을 계획하고 있다. 국방부는 2012년 전시작전통제권 환수에 대비한 독자적인 작전지휘능력 확보가 필요한 상황이며, 미래의 한국군 독자적 네트웍 중심 전장(NCW: Network Central Warfare) 체계 구축을 위해서는 미 공군의 "우주기상작전센터"와 같은 우주기상 예 경보 체계 구축이 요구된다. 이 연구에서는 군의 독자적 우주작전능력 확보를 위한 우주기상 예 경보 체계 구축 방향을 제시하고자 사전기반 연구를 수행하였다. 그 내용으로 우주기상에 대한 개요 및 우주기상의 변화에 따른 국내외 영향을 조사하고 국내외 우주기상 예 경보 시스템을 소개하고자 한다. 또한, 미공군의 우주기상 활용 상태를 점검하여 한국 공군을 위한 우주기상 예 경보 체계 구축 및 인력과 기술 확보에 대한 방안을 제시하고자 한다.