• International Journal of Fluid Machinery and Systems
• /
• 제2권3호
• /
• pp.254-259
• /
• 2009

In this paper it was attempted to treat the hydrodynamic journal bearing as a time-based nonlinear reaction source in each step of rotor rotation in order to observe the bearing effect more realistically and accurately in stead of the conventional method of simple linearized stiffness and damping. Lubrication analysis based on finite element method is employed to calculate the hydrodynamic reaction of bearing and Newmark's method was used to calculate the rotor dynamics in the time domain. Simulation for an industrial electrical motor showed remarkable results with differences compared to those by the conventional method in the dynamic behavior of the rotor.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2000년도 Proceeding of CIN-KIN Joint Symposium 2000 on M.E.T. Under STCW 78/95 and SINO-KOREA MARITIME CONTACT IN MID-CENTURIES
• /
• pp.83-91
• /
• 2000

This paper illustrates a new idea methods and results of WPD oil applied to marine diesel engines. in recent years, we must make an effort to develop an advanced technique for recycling of waste plastics in order to utilize scrapped plastics as fuel source for diesel engine. It is very important and necessary for us to cope with the increasing calorific value and the growing need of environment protection. The experiment fuel oil was obtained by mixing of diesel oil, WPD and water.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2005년도 춘계학술대회 논문집
• /
• pp.333-340
• /
• 2005

본 연구는 부산의 해안야간경관계획을 효과적으로 수립하기 위한 기초연구로서 영도의 해안을 대상으로 야간경관을 평가하는데 그 목적이 있다. 먼저 영도의 해안지역을 8개 야간경관구역으로 나누었으며 각 구역의 야간경관 이미지를 SD분석법(의미분별척도법)을 사용하여 평가하였다. 또한 경관구역별로 경관포인트와 보기좋은 경관요소, 보기싫은 경관요소, 야간경관 문제점 등을 분석하였다.

• 해양환경안전학회:학술대회논문집
• /
• 해양환경안전학회 2007년도 추계학술발표회
• /
• pp.197-205
• /
• 2007

국내에서 가축분뇨를 폐기물의 해양배출에 관한 현황 및 정부와 업계의 입장을 살펴보고, 정부(해양수산 및 농림부)와 업계(대한양돈협회 및 해양배출협회) 간의 갈등을 해결하는 대책을 검토하였다.

• 제어로봇시스템학회논문지
• /
• 제8권1호
• /
• pp.67-73
• /
• 2002

This paper presents the development of development of stabilization and tracking algorithms for a shipboard satellite antenna system. In order to stabilize the satellite antenna system designed in the previous work, a model for each control axis is derived and its parameters are estimated using a genetic algorithm, and the state feedback controller is designed based on the linearized model. Then a tracking algorithm is derived to overcome some drawbacks of the step tracking. The proposed algorithm searches for the best position using gradient-based formulae and signal intensities measured according to a search pattern. The effectiveness of both the stabilization and tracking algorithms is demonstrated through experiment using real-world data.

• Journal of Advanced Marine Engineering and Technology
• /
• 제40권2호
• /
• pp.112-119
• /
• 2016

Many studies have been conducted on the performance of a passive autocatalytic recombiner (PAR), but not many have focused on the locations where the PAR is installed. During a severe accident in a nuclear reactor containment, a large amount of hydrogen gas can be produced and released into the containment, leading to hydrogen deflagration or a detonation. A PAR is a hydrogen mitigation method that is widely implemented in current and advanced light water reactors. Therefore, for this study, a PAR was installed at different locations in order to investigate the difference in hydrogen reduction rate. The results indicate that the hydrogen reduction rate of a PAR is proportional to the distance between the hydrogen induction location and the bottom wall.

• Journal of electromagnetic engineering and science
• /
• 제6권3호
• /
• pp.171-175
• /
• 2006

In this paper, a new semi-lumped low-pass filter with three finite attenuation poles at stopband is presented. The new structure is composed of a pair of symmetrical parallel coupled-line and a shunted capacitor. With this configuration, three finite attenuation poles can be available for 2nd, 3rd, and 4th harmonics suppression. The research method is based on transmission-line model for tuning the attenuation poles. In order to examine the feasibility of the proposed structure, a low-pass filter based on microstrip structure with harmonics suppression is designed, fabricated, and measured. The experimental results of the fabricated circuit agree well with the simulation and analytical ones.

• 해양환경안전학회지
• /
• 제13권3호
• /
• pp.199-206
• /
• 2007

연안여객선 보안위협과 관리제도 현황을 분석하고 관련 종사자들에 대한 보안의식을 설문조사하여 분석함으로서 연안여객선의 보안취약성과 보안위협의 특성을 도출하였다. 이러한 여객선의 보안위협에 효율적으로 식별, 대응하여 보안 취약성 제고를 위하여 보안문화 구축방안을 제안하였다. 또한 국내 연안여객선 현장에서 다양한 보안위협에 대응하기 위한 시스템을 제안하였다.

• Journal of Ship and Ocean Technology
• /
• 제9권1호
• /
• pp.38-46
• /
• 2005

Survivability improvement method for naval ship design has been continually developed. In order to design naval ships considering survivability, it is demanded that designers should establish reasonable damage conditions by air explosion. Explosion may induce local damage as well as global collapse to the ship. Therefore possible damage conditions should be realistically estimated in the design stage. In this study the authors used ALE technique, one of the structure-fluid interaction techniques, to simulate air explosion and investigated survival capability of damaged naval ships. Lagrangian-Eulerian coupling algorithm, equation of the state for explosive and air, and simple calculation method for explosive loading were also reviewed. It is shown that air explosion analysis using ALE technique can evaluate structural damage after being attacked. This procedure can be applied to the real structural design quantitatively by calculating surviving time and probability.

• Journal of electromagnetic engineering and science
• /
• 제1권1호
• /
• pp.100-104
• /
• 2001

Since the most of malfunctions in the industrial equipment controlled by processors is consist of the electrical fast transient (EFT)$^{[1],[2]}$TEX>, the International Electrotechnical Commission (IEC) prepared the dummy signal to test the immunity level of the equipments. To work out a countermeasure for the malfunction, We designed a new electromagnetic compatibility (EMC) filter for high power supply, which is consisted of a feed-through capacitor and ferrite materials with high permeability. The ferrite material is surrounded with a power cable or is inserted on the cable’s second layer in order to increase common-mode inductance. We have obtained a excellent insertion loss characteristics over the frequency band from 150 kHz to 30 MHz. The developed new EMC filter satisfy IEC 61000-4-4 and is suitable for industrial, militaly, and medical equipments with reduced malfuntions.