• Defense and Technology
• /
• no.10 s.272
• /
• pp.72-83
• /
• 2001

현재와 같이 남북이 대치되어 있는 상황하에서는 국가 방위력이 무엇보다도 중요하다. 이러한 측면에서 방산업체는 국가 방위력에 지대한 공헌을 한다고 할 수 있다. 그러나 방산업체는 정부를 상대로, 제한된 시장에서 생산업무를 수행하고 있기 때문에 완전경쟁 시장과는 다른 특수한 상황에 직면하고 있어 그 동안 정부와 방산업체 간에는 상반된 이해관계로 인해 많은 문제점이 있어 왔다. 이 글은 이러한 맥락에서 방산업체가 불신하고 있는 정부의 조달계약제도와 정부가 불신하고 있는 업체의 원가산정 및 관리 측면을 분석하여 제값을 주고 양질의 제품을 정부가 확보할 수 있는 개선방안을 찾고자 했다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2015.10a
• /
• pp.47-48
• /
• 2015

VTSO make a decision which one will be danger and what to expect ship's actions due to each encountering situation with CPA(Closest Point of Approach) and TCPA(Time to Closest Point of Approach) by monitoring ship's vectors(Course & Speeds) in real-time through the VTS system. This study is the fundamental research for developing algorithm and system that does not decide the collision risk in one's own ship's viewpoints, but it identifies the related ships into danger through the third party(VTS ) in real time.

• Journal of Advanced Marine Engineering and Technology
• /
• v.37 no.1
• /
• pp.114-120
• /
• 2013

Recently, navigation systems based on wireless communication have been applied to the internal structures such as building or ship. If a stable azimuth information is obtained, these systems can effectively guide the direction of the user's progress through the information and then can improve the performance of guidance. Since conventional method which has acquired an azimuth information using geomagnetic and acceleration sensor(azimuth sensor hereafter) is sensitive to the effects of the magnetic field, it has unstable error range according to the surrounding environment. In order to improve these problems, this paper presents a new relative azimuth estimation algorithm using the displacement of a mobile node and its rotation angle based on Wireless communication. For the performance assessment of the proposed algorithm, experiments using rotating arm are performed and the results are confirmed that the proposed system can estimate the relative azimuth without using additional sensors.

• The Journal of Engineering Geology
• /
• v.6 no.3
• /
• pp.131-136
• /
• 1996

Attenuation characteristics of AF/MA motions which involve high frequencies were investigated through pencil-lead fracture tests on a fine-grained granite specimen. For the study, calibrated six transducers were employed to detect the signals and the pencil-lead was fractured as a step unloading force to generate AE/MA signals. The arnplitude AE/MA waves is affected by the relative orientation of source and transducer as well as the source distance. The attenuation constant for Charcoal granite is obtained as 1.058 which could be applied for a given ray-path regardless of the relative orientation of source and transducer.

• Defense and Technology
• /
• no.8 s.234
• /
• pp.76-85
• /
• 1998

잠수함은 언제, 어디에서, 어떻게 나타날지 모르는 바다의 게릴라이기 때문에 상대국가에게 해상전력의 상당부분뿐만 아니라 지상전력의 일부까지도 대 잠수함 정찰/감시 임무에 투입하도록 하는 매우 중요한 전략적 가치를 갖는다.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.23 no.5
• /
• pp.447-454
• /
• 2017

Using two large coast guard ships at sea, we created four encounter situations ($000^{\circ}$, $045^{\circ}$, $090^{\circ}$, $135^{\circ}$) with high possibility of collision, from 3 NM up to 0.25 NM. As relative distance was gradually decreased, the subjects were measured at 0.25 NM intervals and perceived ship collision risk (PSCR) was determined by looking at the opponent ship. Characteristics were statistically analyzed using the obtained data. The purpose of this study was to analyze the characteristics of collision risk values obtained from twelve intervals, from 3 NM to 0.25 NM relative to encounter situations by curve fitting with appropriate polynomials, to determine the distance from which the change in perceived collision risk is greatest. As a result, an optimal regression equation for each distance interval was derived from each analysis direction. The greatest variation in average collision risk value was over the range 1.25 ~ 1 NM, and the collision risk value was largest at 1 NM. The maximum change in perceived collision risk was at 1 NM. These results can contribute to preventive guidelines to minimize human error in close proximity situations with a high probability of ship collision.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.3 no.2
• /
• pp.3-12
• /
• 2001

This paper presents the proposed methods of DE (distinct element) modelling to estimate the stability of tunnels in jointed rock masses. First, the criterion to select the joint set(s) contributed to the discontinuous behaviour in a tunnel section is proposed. Selected joint set(s) is(are) considered to form the edges of distinct elements (rock blocks) and the others to modify the elastic properties of rock blocks. The complex DE model with the average and the deviation of joint orientation and joint length for each joint set was compared to the simple model with only the average of joint orientation and the assumption that joint length is infinite. As a result, the latter is suitable to the purpose of tunnel design because it can show the consistent behaviour of a jointed rock mass such as the locally discontinuous failure and the global anisotropic behaviour.

• Convergence Security Journal
• /
• v.23 no.2
• /
• pp.95-102
• /
• 2023

The purpose of this paper was to confirm the operational level of the military department of universities, which plays a key role in the officer training process, through empirical research and confirm meaningful results for improvement. There are 11 university military departments operated through the Army, agreements, and semi-agreement, and the Data Envelopment Analysis (DEA) was applied from the perspective of resource input and performance for each university's military department operation to analyze relative efficiency and confirm specific directions for improvement. As a result of operational efficiency analysis, 6 DMUs (Decsision Making Unit) were found to be efficient in the BCC model out of 11 DMUs, and the evaluation results could be confirmed through classification of efficient and inefficient groups through data capture analysis. This paper may be of practical value in that it checks the efficiency of the comparative university military departments and confirms specific information for development through the DEA-Additive model that reflects several evaluation factors at once. Through this, the operators of each university's military department are admitted.

• Defense and Technology
• /
• no.7 s.257
• /
• pp.38-43
• /
• 2000

전문가들은 예측하기를 미래의 전장은 적을 육안으로 거의 보지 못하고 싸우게 될 것이라 한다. 그리고 군사적으로 주요 요충지마다 로봇 병사가 지키게 될 것이다. 미래전쟁체계는 컴퓨터를 기반으로 하는 체계들로 구성되어 있기 때문에 컴퓨터 체계자체를 지키는 보안 및 안정성이 중요한 무기로 등장할 것이다. 적군의 컴퓨터 해커가 상대의 컴퓨터를 마비시키는 바이러스, 칩변조, 소프트웨어 변조, 시한폭탄 소프트웨어 바이러스, 허위정보 등을 투입할 수도 있다

• Defense and Technology
• /
• no.9 s.271
• /
• pp.62-75
• /
• 2001

방산업체는 정부를 상대로 제한된 시장에서 생산업무를 수행하고 있기 때문에 완전경쟁시장과는 다른 특수한 상황에 직면해 있다고 할 수 있으며 그 동안 정부와 방산업체간에는 상반된 이해관계로 인해 많은 문제점이 있는 것으로 드러났다. 따라서 이 글의 목적은 계약제도의 효율성과 합리성을 구현하기 위해 기존의 계약제도를 미국과 일본의 선진계약시스템과 함께 분석하고, 더욱 발전시켜야 하는 제도는 장려할 수 있도록 방안을 찾고자 한다.