• Journal of Korean Society of Steel Construction
• /
• v.19 no.2
• /
• pp.211-221
• /
• 2007

A structural reliability analysis of fatigue truck model for fatigue failure of highway steel bridges was performed by applying the Miner's fatigue damage rule expressed as a function of various random variables affecting fatigue damage. Among the variables, the statistical parameters for equivalent moment, impact factor, and loadometer were obtained by analyzing recently measured domestic traffic data, whereas the parameters on fatigue strength, girder distribution factor, and headway factor of the measured data available in the literature were used. The effects of various fatigue truck models, fatigue life, ADTT, fatigue detail category, loadometer, and gross vehicle weight of fatigue truck on the reliability index of fatigue damage were analyzed. It is expected that the analytical results presented herein can be used as a basic background material in the calibration of both fatigue design truck and fatigue load factor of LRFD specification.

• Tunnel and Underground Space
• /
• v.26 no.3
• /
• pp.192-200
• /
• 2016

We analyzed the behavior of the lining segments considering the middle slab and lateral pressure coefficients when planning the construction of a duplex tunnel for the underground network. Reviewed segment lining analysis for research, the analytical model was determined for duplex tunnel. Also reviewed the vertical load, and a load of middle slab is considered the static load and the live load by vehicles. Section force by middle slabs a load applied was mainly generated in the lower tunnel had the greatest effect on the bending moment. In addition, the bending moment acting direction changes appeared with a large variable, and the section force according to the load applied to the middle slab is relatively constant and the effect on the segment lining from the smallest section force of the lateral pressure coefficient of 1.00 was found to occur appears most significantly. As a result of this research to identify the behavior of the slab and the segment lining by the effect of the lateral pressure coefficient (K) of the duplex tunnel will be able to present a method of the duplex tunnel structure is reasonable and economical design.

• Journal of Korean Society of Transportation
• /
• v.30 no.2
• /
• pp.127-136
• /
• 2012

Multi-car rear-end collision accidents have three categories: sequential collision from the rear which is commonly referred to as chain reaction collision, sequential collision from the front, and mixed-order collision. This paper suggests several effective methods of reconstruction analysis for multi-car rear-end collision accidents. First, by incorporating the traditional empirical method which uses vehicle damage caused by brake dive and passenger injuries, with results of theoretical analysis made within mechanics of rigid body, it is made possible for the method to be put to immediate practical use. A methodology to precisely analyze multi-car rear-end collision accidents was suggested using a simulation program simultaneously with a video event data recorder which is starting to be widely used in domestic vehicles. To go beyond the simple intuitive analysis of the video event data recorder, the simulation analysis based on the results of video analysis was executed to acquire various information, so that the causes and responsibility could be clearly stated.

• Journal of the military operations research society of Korea
• /
• v.33 no.1
• /
• pp.105-115
• /
• 2007

It is essential to give a fatal damage to the enemy force by using prompt and accurate fire in order to overcome the lack of artillery force. During the artillery fire operations, minimizing the firing time will secure the adapt ability in tactical operation. In this paper, we developed a mathematical model to schedule the artillery fire on the multiple targets to decrease total fire operation time. To design a program to describe a real firing situation, we consider many possible circumstances of changes such as commander's intention, firing constraints, target priority, and contingency plan to make a fire plan in an artillery unit. In order to work out the target sequencing problem, MIP is developed and the optimum solution is obtained by using ILOG OPL. If this analytical model is applied to a field artillery unit, it will improve the efficiency of the artillery fire force operations.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.12 no.5
• /
• pp.1197-1205
• /
• 1988

An analytical method to predict qualitative performance characteristics of the Stirling Engines in the preliminary design stages is investigated. Both the expansion and the compression cylinder are treated as adiabatic and piston motions are approximated as saw-toothed waves. Basic equations which were originally proposed by Finkelstein consist of mass conservation and energy balances for each adiabatic cylinder. The approximation on piston motions and physical conditions make it possible to divide an engine cycle into four fundamental processes. In each process, first, pressure can be expressed as a function of the crank angle by solving a nonlinear first order ordinary differential equation and other thermodynamic variables are determined in turn. Application of the cyclic steady condition to the whole processes can complete a cycle. Also, further analysis results in analytic expressions for cyclic work and heat transfer in terms of the engine parameters and thermodynamic variables at boundary points. The results are expected useful as a quick reference for the engine performances. Finally, the present method can be applied to the other adiabatic analyses on the Stirling Engines with piece wise linear piston motions, if mass variations are predictable.

• Journal of the Korean Society for Library and Information Science
• /
• v.37 no.2
• /
• pp.253-268
• /
• 2003

A bibliographical analysis on folktale studies in Korea by Soyoung Yoo This study is aimed primarily at taking a view of the scope and depth of folktale studies in Korea and analysing their subjects study and directions. By doing so, the researcher hopes that this can be of help to users of those studies. The researcher collected all the studies in this field since 1945 and analysed them through SAS program. Thus, the researcher found the studies on Korean folktales started in late 1960's and flourished and diversified in the middle of the 1990s. The researcher divided the collected materials into two categories, i.e., the study materials which focused on folktales themselves and studies for the exploration of applications of folktales for other purposes. Former analytical study on folktales study themselves is shown to be composed of events, characters, themes and psychological as well as value analysis. there are some comparative studies with folktales of other countries. Latter studies show that the studies are mostly for language educational purpose. Furthermore, they are for illustration, animation, traditional design, costumes studies and theme parks. There are some other studies.

• Journal of the Korean Society for Library and Information Science
• /
• v.8
• /
• pp.157-182
• /
• 1981

The purpose of present study is to investigate children's attitude toward reading, reading method, reading environment, reading volume, and then to compare the results obtained by sex, area and grade. The tool used in this survey was a questionaire designed specially by the investigator. The questionaire was distributed to 1339 children selected at the descretion of the investigator with due consideration of sex, area(large city, medium city and rural community) and grade (from 2nd grade of primary school to 2nd year of middle school). The results of this study are summerized as follows : 1) Regional difference was observed in respect of the followiug : Awareness on reading, motivation for reading, reading method, activity after reading, number of books collected, reading guidance, how to obtain books to read, monthly reading volume, and reading tendency. 2) Also difference by grade was observed in respcet of the following ; Activity after reading, reading guidance, monthly reading volume and reading tendency. The following conclusions have been made based on the results of the survey: 1) The children's attitude toward reading and reading method may be considered favorable while reading environment is not satisfactory yet. Especially, reading environment of school children in medium cities and rural communities is worse than that of large cities. 2) No difference by sex was observed in respect of attitudes toward reading, reading method, reading environment and reading volume while difference by sex was observed in respect of reading tendency. The followings are recommended based on the results of survey: 1) To establish and carry out a comprehensive program for the improvement of reading environment of the school children in medium cities and rural communities. 2) To improve and substantiate school library facilities and design a proper guidance program to have children utilize school library to the maximum extent. 3) To contemplate on the consolidated measures for reading behavior survey.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.23 no.3
• /
• pp.1-1
• /
• 1987

The accurate prediction of the ship wave resistance is very important to design ships which operate satisfactorily in a wave environment. Thus, work should continue on development and validation of methods to compute ship wave patterns and wave resistance. Research efforts to improve the prediction of ship waves and wavemaking resistance are categorized in two major areas. First is the development of higher-order theories to take account of the nonlinear effect of the free surface condition and improved analytical treatment of the body boundary condition. Second is the development of direct numerical methods aimed at solving body and free-surface boundary conditions as accurately as possible. A new formulation of the slender body theory for a ship with constant speed is developed by Maruo. It is quite different from the existing slender ship theory by Vossers, Maruo and Tuck. It may be regarded as a substitute for the Neumann-Kelvin approximation. In present work, the method of asymptotic expansion of the Kelvin source is applied to obtain a new wave resistance formulation in fluid of finite depth. It takes a simple form than existing theory.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.7 no.4
• /
• pp.109-120
• /
• 2003

The state-of-art of curved box girder bridge with cross section design has advanced in various area. In these days, several analytical techniques for behaviors of curved box girder bridges cross section are available to engineers. The transfer matrix method is extensively used for the structural analysis because its merit in the theoretical background and applicability. The technique is attractive for implementation on a numerical solution by means of a computer program coded in Fortran language with a few elements. To demonstrate this fact, it gives good results which compare well with finite element method. Therefore, this paper proposed the static analysis method of curved box bridge with cross section by transfer matrix method based on pure-torsional theory and the optimal span ratio/variable cross section ratio of 3 span continuous curved box girder bridge.

• The Journal of Industrial Distribution & Business
• /
• v.5 no.4
• /
• pp.31-42
• /
• 2014

Purpose - According to the applied studies knowledge, management implementation can improve organizational performance. The main objective of this study is to develop an understanding of critical success factors that enhance the successful implementation of knowledge management. Research design, data, and methodology - This study used Analytical Hierarchy Procedure (AHP), which is a multi-criteria decision making model that works on fuzzy logic. Using this method, researchers can find the proportion of success due to the contribution of the critical success factors (CSFs). Results - The results show that more than 70% of respondents indicate the possibility of success in knowledge management implementation. Further, the results show that top management support has the greatest relationship with the success of knowledge management implementation. This was followed by information technology, performance measurement, and culture, which had a high relation with knowledge management success. Process and activities have a moderate positive relation, while education and training has a low relation with success. Because of an inappropriate p-value, knowledge management strategies show no relation to the success of knowledge management in the Iranian health Industry. Conclusions - This study was conducted because of a critical issue in the Iranian health industry that indicated that a significant portion of the workforce would retire in 5 to 10 years. Most highly experienced and knowledge oriented employees would become eligible for retirement. Therefore, knowledge management is presented as a complete solution in the Iranian health sector.