• Defense and Technology
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• no.3 s.169
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• pp.36-45
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• 1993

유도탄에 의존하는 전투 경향은 향후 계속적으로 증대될 것이며 더구나 유도탄은 지금까지 설명한 것 같이 장거리화, 고속화, 스텔스화, 고고도 또는 저고도 탄도선택, 명중 직전까지 탐지 곤란 및 최종유도 단계에서 고가속도 운동 등 성능은 향상 일로에 있습니다. 함정의 생존성을 제고시키기 위한 각국의 대함유도탄 방어체계 개발 노력은 함정 탑재 무기체계인 근접방어 무기체계, 함대공유도탄, ESM 및 유도탄 기만 장치의 지속적인 성능개량과 함께 지속될 것입니다

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.739-742
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• 1997

A remote drum grappling device coupled to the anti-swing crane has been developed by KAERI to cope with problems involved in manually treating low level waste drums. In order for this grappling device to be operated effectively, multi-sensors including CCD camera were employed. As an activity representation scheme of the device, Extended State Machine (ESM) was used to descibe its operation sequences. The performance testing of the device was conducted successfully, and consequently its application could be extendable to industrial operation environment.

• Defense and Technology
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• no.2 s.156
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• pp.14-19
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• 1992

유럽 무기체계의 공통사항은 주요 방산업체를 국가가 주도적으로 운영하고 있고, 개발위험부담을 줄이기 위해 국가간 공동개발 및 합작생산을 추구하고 있다는점이다. 유럽은 공동개발 체제하에 항공기를 생산함으로써 각국이 개발한 무기간의 호환성을 증대시켜 왔으며, 개발비 부담을 감소시켜 왔다. 또한 단일기종으로 ESM, ECM, 정찰임무 등의 복합임무가 가능하므로 제한된 전장지역에 적합하며, 침단기술 이전 면에서도 적극적인 자세를 보이고 있다. 한국 공군에서도 무기체계도입 및 기술협력 다변화를 위해, 앞으로 유럽 무기체계에 대한 적극적인 관심이 필요하리라 생각된다

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.4
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• pp.36-45
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• 2008

LYNX ESM system operates digital receiver for analyzing radar of intrapulse modulation signal. This paper contains DC offset compensation method of IQ channels, imbalancing comensation method of amplitude and phase, precisional PW measurement using adaptive threshold set, analyzing algorithm of intrapulse modulation signals. Its effectiveness was proven by technical and operational test.

• Convergence Security Journal
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• v.6 no.1
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• pp.1-11
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• 2006

The exponential increase of malicious and criminal activities in cyber space is posing serious threat which could destabilize the foundation of modem information society. In particular, unexpected network paralysis or break-down created by the spread of malicious traffic could cause confusion and disorder in a nationwide scale, and unless effective countermeasures against such unexpected attacks are formulated in time, this could develop into a catastrophic condition. As a result, there has been vigorous effort and search to develop a functional state-level cyber-threat early-warning system however, the efforts have not yielded satisfying results or created plausible alternatives to date, due to the insufficiency of the existing system and technical difficulties. The existing cyber-threat forecasting and early-warning depend on the individual experience and ability of security manager whose decision is based on the limited security data collected from ESM (Enterprise Security Management) and TMS (Threat Management System). Consequently, this could result in a disastrous warning failure against a variety of unknown and unpredictable attacks. It is, therefore, the aim of this research to offer a conceptual design for "Knowledge-based Real-Time Cyber-Threat Early-Warning System" in order to counter increasinf threat of malicious and criminal activities in cyber suace, and promote further academic researches into developing a comprehensive real-time cyber-threat early-warning system to counter a variety of potential present and future cyber-attacks.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.6
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• pp.625-630
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• 2010

With regard to the examples of establishing various sorts of information security, it can be seen that there are gradual, developmental procedures including Firewall and VPN (Virtual Private Network), IDS (Intrusion Detection System), or ESM(Enterprise Security Management). Each of the security solutions and equipments analyzes both defense and attack for information security with the criteria of classifying the problems of security policies by TCP/IP layers or resulted from attack patterns, attack types, or invasion through specialized security technology. The direction of this study is to examine latency time vulnerable to invasion which occurs when L2-stratum or lower grade equipments or policies are applied to the existing network through TCP/IP layer's L3-stratum or higher grade security policies or equipments and analyze security holes which may generate due to the IP preoccupation in the process of establishing policies to limit particular IP area regarding the policies for security equipments to figure out technological problems lying in it.

• Applied Chemistry for Engineering
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• v.25 no.6
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• pp.592-597
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• 2014

The graphite/$SiO_2$ composites as anode materials for lithium-ion batteries were prepared by sol-gel method to improve the graphite's electrochemical characteristics. The prepared graphite/$SiO_2$ composites were analysed by XRD, FE-SEM and EDX. The graphite surface modified by silicon dioxide showed several advantages to stabilize SEI layer. The electrochemical characteristics were investigated for lithium ion battery using graphite/$SiO_2$ as the working electrode and Li metal as the counter electrode. Electrochemical behaviors using organic electrolytes ($LiPF_6$, EC/DMC) were characterized by charge/discharge, cycle, cyclic voltammetry and impedance tests. The lithium ion battery using graphite/$SiO_2$ electrodes had better capacity than that of using graphite electrodes and was able to deliver a discharge capacity with 475 mAh/g at a rate of 0.1 C. Also, the capacity retention ratio of the modified graphite reaches 99% at a rate of 0.8 C.

• Journal of Digital Convergence
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• v.13 no.2
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• pp.227-235
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• 2015

The aim of this study was to identify the type of occupational balance of college students and analyze the differences between positive or negative emotions according to degree of flow. The Experience Sampling Methods (ESM) were conducted for 12 college students using smart phones. As a result, in activities of daily living group, apathy showed the highest percentage (34%) and in over work group, flow showed the highest percentage (41%). In occupational balance group, frequency of labor and leisure activities was high but boredom was experience a lot in leisure activities. When the students experienced flow in main activities, mean score of positive emotions showed the highest value. Through this study, we identified the differences of flow experience in occupational performance based on type of occupational balance and confirmed improvement of positive emotions in activities experienced flow.

• Structural Engineering and Mechanics
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• v.21 no.6
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• pp.713-735
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• 2005

Due to the complexity of mathematical expressions, the literature concerning the free vibration analysis of plates carrying multiple three-degree-of-freedom (dof) spring-mass systems is rare. In this paper, the three degrees of freedom (dof's) for a spring-mass system refer to the translational motion of its lumped mass in the vertical ($\bar{z}$) direction and the two pitching motions of its lumped mass about the two horizontal ($\bar{x}$ and $\bar{y}$) axes. The basic concept of this paper is to replace each three-dof spring-mass system by a set of equivalent springs, so that the free vibration characteristics of a rectangular plate carrying any number of three-dof spring-mass systems can be obtained from those of the same plate supported by the same number of sets of equivalent springs. Since the three dof's of the lumped mass for each three-dof spring-mass system are eliminated to yield a set of equivalent springs, the total dof of the entire vibrating system is not affected by the total number of the spring-mass systems attached to the rectangular plate. However, this is not true in the conventional finite element method (FEM), where the total dof of the entire vibrating system increases three if one more three-dof spring-mass system is attached to the rectangular plate. Hence, the computer storage memory required by using the presented equivalent spring method (ESM) is less than that required by the conventional FEM, and the more the total number of the three-dof spring-mass systems attached to the plate, the more the advantage of the ESM. In addition, since manufacturing a spring with the specified stiffness is much easier than making a three-dof spring-mass system with the specified spring constants and mass magnitude, the presented theory of replacing a three-dof spring-mass system by a set of equivalent springs will be also significant from this viewpoint.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.6
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• pp.611-619
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• 2016

Success in modern war depends on electronic warfare. Therefore, It is very important to identify the kind of Radar PRI modulations in a lot of Radar electromagnetic waves. In this paper, I propose an algorithm to identify Linear up Sliding PRI, Non-Linear up Sliding PRI and Linear Down Sliding PRI, Non-Linear Down Sliding PRI among many Radar pulses. We applied not only the TDOA(Time Difference Of Arrival) concept of Radar pulse signals incoming to antennas but also a rising and falling curve characteristics of those PRI's. After making a program by such algorithm, we input each 40 data to those PRI's identification programs and as a result, those programs fully processed the data in according to expectations. In the future, those programs can be applied to the ESM, ELINT system.