• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2016.05a
• /
• pp.194-195
• /
• 2016

IMO에서 규정하는 모든 교육 및 훈련을 이수한 전문 해기인력이 매년 배출되고 있지만, 해양사고의 발생은 끊이지 않고 있다. 이는 해양사고를 대처하는 해기사의 위험상황 대처 능력이 크게 개선되지 않았다는 점을 의미한다. 공통적으로 해기사에게 제공되는 교육 및 훈련뿐만 아니라 해기사 개개인의 위험요소를 파악하여 해당 위험 요소에 대한 매뉴얼을 제공할 수 있는 모델이 개발되면 해양사고를 대처할 수 있다. 이러한 모델을 개발하기 위하여 모델 구축에 필요한 데이터베이스(Data Base, D/B)가 필요하다. 이러한 D/B는 모델에 활용할 수 있도록 숫자로 표기된 것이어야 한다. 본 연구에서는 해양안전심판원에서 제공하는 해양사고 데이터를 수집, 분석하여 해양사고 예방을 위한 모델에 활용할 수 있는 해양사고 수량화 D/B를 구축하는 방법에 대하여 고찰하였다. 1차적으로 해양사고 수량화 D/B를 구축하였으나, 이의 유용성이나 목적에 적합한 D/B의 규모 등에 관한 연구는 추후에 계속 되어야 한다.

• Journal of Satellite, Information and Communications
• /
• v.12 no.4
• /
• pp.110-114
• /
• 2017

Using a small mobile wireless network as a supplement to the disaster safety network can be useful for eliminating small radio shadowing areas, reducing traffic overloads in disaster areas, and quickly building a disaster communication network in difficult access areas. Potable base station is needed to build a small mobile wireless network, and the portable base station using TVWS(TV White Space) is effective in terms of utilization of radio frequency resources and construction cost of wireless networks. In this paper, we design and implement a power amplifier for portable base station operating in TVWS. The implemented power amplifier operates at 470 ~ 698MHz. The gain of the implemented amplifier is more than 20.1dB, the input/output return loss is more than 11.4dB, and the isolation is more than 39.9dB when the output is off. The IMD characteristic of the power amplifier has characteristics of 61.0dBc with 18.8dBm output at 470MHz, 59.3dBc wih 18.6dBm output at 550MHz and 56.5dBc with 19.0dBm output at 690MHz. The power amplifier implemented in this paper can be used as a power amplifier for portable base station.

• The Journal of the Acoustical Society of Korea
• /
• v.20 no.5
• /
• pp.76-82
• /
• 2001

Because the biological tissue with inhomogeneous acoustic properties does not keep a particular shape, the measurement of propagation characteristics of ultrasonic fields by the conventional scanning method with a miniature hydrophone is difficult. In this study, a two-dimensional may hydrophone was fabricated using the PVDF (Polyvinylidene fluoride) piezo-electric film and a ultrasonic field measurement system with it was established. For the acoustic field produced by a circular plan transducer with center frequency of 2.25㎒ and 13㎜ in diameter, it was possible to make a fairly accurate field measurement using the hydrophone system. The attenuation coefficients at 2.25 ㎒ for biological tissues were 0.7∼1.3 dB/cm(average; 1.0 dB/cm) in bovine liver, 1.0∼1.8 dB/cm (average; 1.6 dB/cm) in pig liver, 0.9∼2,9 dB/cm(average: 2.1 dB/cm) in bovine muscles, 1.7∼3.3 dB/cm (average; 2.5 dB/cm) in pig muscles.

• Journal of the Korean Society for Railway
• /
• v.9 no.3 s.32
• /
• pp.10-16
• /
• 2006

• Journal of IKEEE
• /
• v.24 no.1
• /
• pp.238-242
• /
• 2020

This paper presents a technique using a multilayered dielectric coating to reduce the radar cross section (RCS) value of an integrated mast mounted in a destroyer. The proposed multilayer structure has the advantage of being easy to fabricate because the dielectric constant is defined so that a general dielectric that does not contain a magnetic component that requires high dielectric constant or is frequently used for blocking electromagnetic wave absorption can be used. After applying the proposed multi-layer dielectric structure to the integrated mast shape, the simulation results show that the RCS reduction performance is 10.9dB at 6GHz, 11.95dB at 12GHz, and 11.63dB at 18GHz compared to the structure without the multilayer structure.

• Journal of Korean Society for Geospatial Information Science
• /
• v.10 no.1 s.19
• /
• pp.77-82
• /
• 2002

This study try to attempt to manage on-line system of land cadastral by computing land registration information, for application to computerized cadastral work through Geo-Spatial Information System. And also, in order to consult D/B of cadastral information, cadastral non-coincidence area uncapable to D/B when land-survey, taking advantage of GSIS drawing made by the present condition drawing and the aerial photograph survey by general survey, makes actual cadastral control point by some selected investigators. And so, it can be compared and analysed by the result of the present survey and, through the interpretation of the relatives, it aims to improve the precision of survey technique in consulting cadastral information D/B in the future.

• The KIPS Transactions:PartD
• /
• v.10D no.1
• /
• pp.167-174
• /
• 2003

Today in Korea, various types of B2B or B2C businesses are carried out on the Internet and the catalog information is the molt important factor to make customers purchase the product. However, no case can be found where information is shared between the business partners, more specifically, each catalog supplier possesses data that are incompatible with others. Though the e-business market has rapidly expanded, it is still difficult for businesses to attract buyers unless an integrated system is provided for more fast and convenient B2B businesses. Such a systematic and integrated catalog system is highly demanded along with current database management system Therefore, this study suggests the E-Catalog system consists of a fixed and standardized catalog system offering product information and a network-based architecture offering products to customers through a search system. The proposed system also supports CRM (Customer Relation Management).

• Journal of Navigation and Port Research
• /
• v.28 no.1
• /
• pp.1-8
• /
• 2004

The final goal of this research is to establish the relative dangerousness D/B for factors on seakeeping performance. This D/B is, essential to develope the seakeeping performance evaluation system built-on-ship. The system is composed of the apparatus for measuring a vertical acceleration to be generated by the ship's motions, computer for calculating the synthetic seakeeping performance index and monitor for displaying the evaluating diagram of navigational safety of ship. In this paper, a methodology on the establishment of the relative dangerousness D/B for factors on seakeeping performance is presented by a numerical simulations, playing an important role on the algorithm of the program for calculating the synthetic seakeeping performance index. Finally, It is investigated whether the relative dangerousness D/B can be realized an accurate values according to the loading conditions, weather conditions, wave directions and present ship's speed of a model ship.

• The KIPS Transactions:PartB
• /
• v.14B no.6
• /
• pp.423-430
• /
• 2007

Optical coherence tomography(OCT) is a high resolution imaging system which can image the cross section of microscopic organs in a living tissue with about $1{\mu}m$ resolution. In this paper, we implement OCT system and acquire 2-D images of rat eye and human molar samples especially in the field of opthalmology and dentistry. In terms of 2-D images, we reconstruct 3-D OCT images which give us another inner structural information of target objects. OPEN-GL reduces the 3-D processing time 10 times less than MATLAB.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2003.05a
• /
• pp.51-59
• /
• 2003

Marine Casualty Forecasting System (MCFS) is to broadcast the prediction number and risk level of marine casualties as like daily weather forecasting. The MCFS consists of marine casualty numerical D/B, prediction model and, three-dimensional statistics visualization system. The implementation procedure for the numerical D/B is described in the paper. The data relating to a total of 724 ship casualties in the west-southern sea area (latitude 33$^{\circ}$N∼35$^{\circ}$ and longitude 124$^{\circ}$E∼127$^{\circ}$E) of Korean peninsula for 11 years (1999∼2000) have been compiled. The analysis method of numerical D/B is proposed and discussed its usability.