• Journal of the Society of Naval Architects of Korea
• /
• v.38 no.4
• /
• pp.48-55
• /
• 2001

In this paper, sensitivity analysis for the coupled axial and torsional undamped free vibration of ship propulsion shafting is proposed. The purpose of this study is to effectively and optimally design the resonance frequencies of propulsion shafting affecting barred speed range of main engine by modifying the diameters of intermediate and propeller shafts. The presented method is validated by the sensitivity analysis for the natural frequencies of propulsion shafting of two real large merchant ships. In addition, the changes of natural frequency and resonance main engine speed are discussed in case that the diameter is varied within the range regulated by the rule of shipping register.

• Annual Conference on Human and Language Technology
• /
• 2001.10d
• /
• pp.422-427
• /
• 2001

질의어 변환 방법은 다국어 정보검색을 위한 방법중에 효율적인 방법이다. 양질의 질의어 변환을 위해서, 사전, 온톨로지, 병렬 코퍼스 통과 같은 자연언어 자원이 필요하다. 이러한 자연언어 자원은 양질로 대량으로 구축하려면 많은 비용이 튼다는 단점이 있다. 본 논문에서는 한영 질의어 변환에 적용할 수 있는 공통 중간개념 구축방법을 제안한다. 공통 중간개념은 동사들의 축으로 이루어지며, 통사들은 기본동사들의 조합으로 표현한수 있다고 가정한다. 공통 중간개념은 적은 자연언어 자원을 효율적으로 이용할 수 있도록 한다. 본 논문에서는 기본 동사 축을 특이값 분해(singular value decomposition) 방법으로 구하고, 그 기본 동사 축을 이용해서 질의어 변환하는 방법을 보여준다.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.10 no.3
• /
• pp.185-191
• /
• 2002

A window-based multibody dynamics program CADyna(Computer Aided Dynamics) is developed and applied for kinematic and dynamic analysis ova steering system. The program is composed oft pre-processor, a main processor, and a post-processor. The pre-processor is developed with Visual C7+ and the post-processor is developed with OpenGL and TeeChart. The main processor generates the equations of motion employing velocity transformation technique. The developed program is customized for the design of an intermediate shaft in a steering system.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.9 no.4
• /
• pp.147-153
• /
• 2000

This paper presents a design method using CAE(Computer Aided Engineering ) with the consideration of reliability for optimal gear driving system. This method considered a configuration of the intermediate shaft. There are four mounting types, such as double straddle, double overhung, output gear overhung, and input ger overhung in the intermediate shaft. The reliability and life analysis are based on the two-parameter Weigbull distribution lives of the gears and bearing . The validity and feasibility of the proposed method are verified by the application to transmission of a industry machine.

• Journal of the Korean Institute of Gas
• /
• v.20 no.3
• /
• pp.73-77
• /
• 2016

This paper presents the displacement behavior safety of hollow shafts with an equivalent volume for various cross sectional area using a finite element method. The FEM results indicate that the hollow shafts with X-type or Y-type columns between outer tube, middle tube and inner tube may reduce a maximum displacement at the middle length of hollow shafts. Especially, the load-bearing column of X-type or Y-type hollow shaft is directly connected between outer tube and inner tube without a shift for reducing the vertical displacement. And increased thickness of a load-bearing column is recommended for reducing the vertical displacement and increasing the displacement behavior safety for an equivalent volume of a hollow shaft.

• Journal of Korea Water Resources Association
• /
• v.52 no.7
• /
• pp.493-503
• /
• 2019

This study presents a new method of estimating the size distribution of river bed gravel through image processing. The analysis was done in two steps; first the individual grain images were analyzed and then the grain particle segmentation of river-bed images were processed. In the first part of the analysis, the relationships (long axes, intermediate axes and projective areas) between grain features from images and those measured were compared. For this analysis, 240 gravel particles were collected at three river stations. All particles were measured with vernier calipers and weighed with scales. The measured data showed that river gravel had shape factors of 0.514~0.585. It was found that the weight of gravel had a stronger correlation with the projective areas than the long or intermediate axes. Using these results, we were able to establish an area-weight formula. In the second step, we calculated the projective areas of the river-bed gravels by detecting their edge lines using the ImageJ program. The projective areas of the gravels were converted to the grain-size distribution using the formula previously established. The proposed method was applied to 3 small- and medium- sized rivers in Korea. Comparisons of the analyzed size distributions with those measured showed that the proposed method could estimate the median diameter within a fair error range. However, the estimated distributions showed a slight deviation from the observed value, which is something that needs improvement in the future.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.34 no.4
• /
• pp.325-330
• /
• 1989

This study was undertaken to assess the effects of seed treatment and soil moisture content on mesocotyl elongation in rice seedlings. The effect of the high temperature pre-treatment on the mesocotyl elongation was 7 times as great as the control (non treatment). The mesocotyl lengths were of maximum value at the 8％ soil moisture, but of minimum value at the 16％ soil moisture plot, showing decreasing trend of mesocotyl length as soil moisture increases. The mesocotyl elongations were much greater at the ABA treated plot than at the GA$^3$, IAA and Kinetin plots. The relationship between the mesocotyl and excised root elongations was not evident, but the weight of excised roots became heavier with longer mesocotyl length.

• Journal of the Korea Society of Computer and Information
• /
• v.13 no.2
• /
• pp.153-158
• /
• 2008

Blocking artefact noise is necessarily happened in compressed images using block-coded algorithms such as JPEC compressing algorithm. This noise is more recognizable especially in highly compressed images. In this paper, an algorithm is presented for reduction of blocking artefact noise using wavelet. Furthermore, we also mention about the median filter which is often used in image processing. Moreover, we compared the algorithm in this paper with the median filter, and its result was much better than the median filter both visually and numerically.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.5 no.1
• /
• pp.45-49
• /
• 2006

목적: 자가 골-슬개건-골과 슬괵건을 이용한 전방 십자 인대 재건술의 5년 중기 추시 결과를 비교 분석하고자 한다. 대상 및 방법: 전방 십자 인대 재건술을 시행한 후 5년 이상 추시 관찰이 가능한 65예를 대상으로 하였고, 골-슬개건-골이 38예, 슬괵건이 27예였다. 술 후 평가는 Lysholm 점수, 관절 운동 범위, 대퇴부 중간 부위 둘레 길이, Lachman 검사, 축 이동 검사, KT 2000 관절 계측기를 시행하였고, 술 후 합병증을 평가하였다. 결과: Lysholm 점수는 골-슬개건-골군과 슬괵건국에서 각각 평균 91점, 94.2점으로 슬괵건군이 우수하였고, 대퇴부 중간 부위 둘레 길이는 건측에 비해 각각 평균 1.7cm, 1.3cm의 차이를 보였다. 양 군간에 관절 운동 범위, Lachman 검사, 축 이동 검사 및 KT 2000 관절 계측 결과는 통계적으로 유의한 차이가 없었으나, 술 후 합병증은 과도한 보행이나 운동 후 슬관절 동통이 골-슬개건-골군에서 7예, 슬괵건 군에서 4예 관찰되었고, 전방 슬관절 동통이 골-슬개건-골군에서 4예 관찰되어, 골-슬개건-골군에서 더 많이 발생하였다. 결론: 5년 중기 추시에서 자가 슬괵건군이 우수한 슬관절 기능, 적은 합병증 등 임상적으로 우수하였으나 장기 추시가 요할 것으로 사료된다.

• Journal of Korean Society of Steel Construction
• /
• v.17 no.5 s.78
• /
• pp.627-636
• /
• 2005

The analysis and design procedure of intermediate support strut for the innovative prestressed scaffolding (IPS) system was presented in this paper. The stability check of intermediate support strut is required as the behavior of the strut system is similar to that of the built-up column. The computer analysis model of the support strut was constructed for in-plane and out-of-plane buckling analysis, and the design of the support strut was performed. Using the eigenvalue for the buckling load and the member forces of support strut under design earth pressure, the effective buckling length was estimated. The allowable axial and bending stresses were calculated considering the effective buckling length. The combined stresses due to these axial forces and bending moment were estimated to be satisfied the safety condition of the intermediate support strut.