• Journal of the Korean Society of Manufacturing Process Engineers
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• v.8 no.2
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• pp.18-24
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• 2009

The most dominate aspect in machine works using CNC devices in industrial production processes is the precision of the product and the Cycle Time. To this day, many studies on the external factors of the technology to reduce the Cycle Time have advanced amid to the advancements in cam soft development for manual programs and the numerous studies on high speed and precision machining. This study experimented various functions of the sequence pattern flow and arranged system development technologies of past few years to develop and applicate various usage of adjustment factors within the CNC, so it would be more understandable to the user and would enable them to make high speed and precision products more faster develop and. In order to reduce the Cycle Time, the mechanism of machine tools has to be analysed and applied, in addition to program reduction and improvement of the manufacture process.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.4
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• pp.293-300
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• 2006

Utilizing a building model design of the investigation factors and structured questionnaire, the results of an investigation concerning the improvement factors in the construction phase, as perceived by academic staffs including graduate students, designers, contractors and property management teams, are presented. Findings reveal that management commitment dominate improvement factors for building projects, although construction firms frequently mentioned the team work in design firms. Significant improvements in building projects are obtained when college programs include courses that treat the administrative aspects involved in the building project and that continuing education programs cover quality training. Eighteen predominant selection factors are identified, ranked and correlated.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.51-60
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• 2002

An analysis method to predict performance of a vehicle cooling system which is composed of radiator, A/C condenser, cooling fan, and etc. is suggested. Air flow through the heat exchanger system and heat rejection rate which dominate the cooling performance are analyzed. Heat transfer with A/C refrigerant phase change is also considered in the analysis. Some predicted results are compared with experimental data for various operating conditions. This evaluation procedure will be useful for the design of optimal vehicle cooling system.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2008.10a
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• pp.3-16
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• 2008

The underground construction and mining are facing many geomechanics challenges stemming from, geological complexities and stress-driven rock mass degradation processes. Brittle failing rock at depth poses unique problems as stress-driven failure processes often dominate the tunnel behaviour. Such failure processes can lead to shallow unravelling or strainbursting modes of instability that cause difficult conditions for tunnel contractors. This keynote address focuses on the challenge of anticipating the actual behaviour of brittle rocks in laboratory testing, for empirical rock mass strength estimation, and by back-analysis of field observations. This paper summarizes lessons learned during the construction of deep Alpine tunnels and highlights implications that are of practical importance with respect to constructability. It builds on a recent presentation made at the $1^{st}$ Southern Hemisphere International Rock Mechanics Symposium held in Perth, Australia, in September this year, and includes results from recent developments.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1652-1653
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• 2011

This paper builds a printed circuit board to calculate the radiated emissions due to the common-mode and differential-mode currents. The calculated results agree with the measured values. Based on the calculated values, it is shown clearly that the common-mode radiations are the dominator of the radiated emissions from the device. The radiated emissions due to the common-mode currents can easily dominate the radiated emissions from the printed circuit board.

• Korean Journal of Mathematics
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• v.15 no.2
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• pp.101-114
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• 2007

For an $m$ by $n$ nonnegative real matrix A, the maximal column rank of A is the maximal number of the columns of A which are linearly independent. In this paper, we analyze relationships between ranks and maximal column ranks of matrices over nonnegative reals. We also characterize the linear operators which preserve the maximal column rank of matrices over nonnegative reals.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 1999.03a
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• pp.403-413
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• 1999

Today's businesses are experiencing intensive global competition and the most accelerating pace of change ever. Competitors have sprung up that were not even on the business's radar. This environment impacts all decisions and strategies as business try to dominate their market or their marker or their industry merely to survive. So recently most of organizations are considering on building the data warehouse system to pursuit the business intelligence. We need the proper model to guide the approach to plan building data warehouse system when we want to plan it in considering the organizational status. Therefore we suggest a model to decide the approach to build data warehouse considering the project's environmental factors. First we review Ronald S. Swift(1998)'s five environmental factors that we have to consider when planing to build data warehouse. Then we propose a model to decide DW approach by the degree of those factors to be measured. DW approaches in this model are classified in conservative approach, increasing approach, enterprise wide approach, and ideal approach.

• Journal of computational fluids engineering
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• v.6 no.4
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• pp.1-7
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• 2001

Wind flow perturbations, recirculations and turbulence generated by buildings often dominate air pollutant distributions around buildings. This paper describes dispersion of contaminants in the vicinity of a building by solving the concentration equation based on previously simulated wind flow field. Turbulence closure is achieved by using the standard k-ε two-equation model. The paper shows application of the CIP method for solving a species concentration equation of contaminant gas around a rectangular building for two different sources under conditions of neutral atmospheric stratification. Results have been compared to the experimental data and the previous numerical results by hybrid scheme. The computational results of concentration profiles by the CIP method agree well with experimental data.

• Journal of the Korean Society of Safety
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• v.25 no.5
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• pp.1-6
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• 2010

When the ceramic material is being machined, micro crack and brittle fracture dominate the process of material removal. Generally, ceramics are very difficult-to-cut materials and machined using conventional method such as grinding and polishing. However, such processes are generally cost-expensive and have low material removal rate. Machinable ceramics used in this study contain BN powder to overcome these problem and for productivity elevation. This paper focuses on machinability evaluation during end mill process with CNC machining center in this study. Experiment for this purpose is performed for tool wear patterns and mechanism.

• Journal of Intelligence and Information Systems
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• v.3 no.1
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• pp.47-68
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• 1997

This paper discusses a method of modified Elman network(1990) for nonlinear predictions and its a, pp.ication to forecasting daily exchange rate returns. The method consists of two stages that take advantages of both time domain filter and modified feedback networks. The first stage straightforwardly employs the filtering technique to remove extreme noise. In the second stage neural networks are designed to take the feedback from both hidden-layer units and the deviation of outputs from target values during learning. This combined feedback can be exploited to transfer unconsidered information on errors into the network system and, consequently, would improve predictions. The method a, pp.ars to dominate linear ARMA models and standard dynamic neural networks in one-step-ahead forecasting exchange rate returns.