• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.470-472
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• 1987

This paper deals with the continuous-discrete estimation problem using FIR filters and performs modeling error analyses of the FIR filters, compared to Kalman filter and the limited memory filters, via computer simulations. It is shown that, the less driving noise the system has, the better performance the FIR filter exhibits and that this characteristic appears rare distinctly in nonlinear system than in linear systems.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.265-270
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• 2002

In this paper, structural behaviors of anchor systems subjected to shear loads are analyzed by using fracture analysis and experiments. Two dimensional finite element analyses of concrete anchor systems to predict breakout failure of concrete through progressive fracture are carried out by utilizing the so-called embedded crack model. Three dimensional finite element analyses are also carried out to investigate the fracture behavior of anchor systems having different effective lengths, edge distances, spacings between anchors, and direction of loads. Results of analyses are compared with both experimental results and design values of ACI code on anchor, and then applicability of finite element method for predicting fracture behavior of concrete anchor systems is verified.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.2
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• pp.94-106
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• 2004

Determining those gaps in agricultural and other information to improve agrometeorological analyses for agriculture is a large task. The effective integration of appropriate data systems, including remote sensing systems, with agricultural systems modelling capability is described as a worthy outcome in this endeavour. Data issues, including those associated with data length, quality, maintenance, and archiving remain serious issues to be addressed. The role of remote sensing and geographic information systems in agrometeorology is important and is explored here. The value of simulation models to provide the synthesis for future agrometeorological requirements is further elucidated.

• Journal of Construction Engineering and Project Management
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• v.5 no.3
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• pp.18-28
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• 2015

Bidding and contract systems are used for public construction projects to select contractors following fair competition principles and to execute national budgets effectively. Many challenges have arisen due to a lack of transparency and fairness and because bidding practices have been luck-based. Few comprehensive or comparative analyses have been conducted on the performance and limitations of bidding and contract systems, and empirical analyses designed to improve policies on and the practice of such systems are lacking. This study empirically analyzed current bidding and contract systems to seek ways of improving them. The study proposes several alternatives to resolve the problems with and irrationalities of the current system: 1) improving bidding and selection systems by changing them from a luck-based price competition into a technical merit- and value-based competition; 2) improving the assessment criteria to meet the current market level of bid and winning prices; 3) adjusting contractual responsibilities and sharing structures to meet the current trend; and 4) strengthening the competitiveness and expanding the social responsibility-based procurement systems of construction companies.

• Earthquakes and Structures
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• v.10 no.2
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• pp.409-428
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• 2016

To realise the full benefits of a self-centering seismic resilient system, the designer must ensure that the entire structure does indeed re-center following an earthquake. The idealised flag-shaped hysteresis response that is often used to define the cyclic behaviour of self-centering concrete systems seldom exists and the residual drift of a building subjected to an earthquake is dependent on the realistic cyclic hysteresis response as well as the dynamic loading history. Current methods that are used to ensure that re-centering is achieved during the design of self-centering concrete systems are presented, and a series of cyclic analyses are used to demonstrate the flaws in these current procedures, even when idealised hysteresis models were used. Furthermore, results are presented for 350 time-history analyses that were performed to investigate the expected residual drift of an example self-centering concrete wall system during an earthquake. Based upon the results of these time-history analyses it was concluded that due to dynamic shake-down the residual drifts at the conclusion of the ground motion were significantly less than the maximum possible residual drifts that were observed from the cyclic hysteresis response, and were below acceptable residual drift performance limits established for seismic resilient structures. To estimate the effect of the dynamic shakedown, a residual drift ratio was defined that can be implemented during the design process to ensure that residual drift performance targets are achieved for self-centering concrete wall systems.

• Asia pacific journal of information systems
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• v.10 no.3
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• pp.1-16
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• 2000

The purpose of this research is to validate the determinants of information systems(IS) sourcing strategy focusing on Korean financial institutions. Based on the factor analyses and discriminant analyses using data from 34 major Korean financial institutions, we observed that determinants of IS souring strategy are perceived risks, strategic expectations and organizational IS maturity. If the clients have clear objectives, can control the risks from IS sourcing, and have information systems in the less-matured stage, they frequently outsource their IS. In view of the IS maturity, previous studies suggest that more-matured IS are outsourced. But the results of this study show that more-matured IS are insourced. These phenomena can be explained by classifying IS by their functions. Transaction processing systems, which are mission-critical, are generally insourced, but decision support systems, which are in their mature state, are generally outsourced.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2005.09a
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• pp.15-20
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• 2005

We developed a database system to enable efficient and high-throughput transposon analyses in rice. We grow large-scale mutant series of rice by taking advantage of an active MITE transposon mPing, and apply the transposon display method to them to study correlation between genotypes and phenotypes. But the analytical phase, in which we find mutation spots from waveform data called fragment profiles, involves several problems from a viewpoint of labor amount, data management, and reliability of the result. As a solution, our database system manages all the analytical data throughout the experiments, and provides several functions and well designed web interfaces to perform overall analyses reliably and efficiently.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.105.6-105
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• 2001

Fish schools behave like a single organism and offer a considerable survival advantage. In our simulations, the fish school is well organized and behaves like a single creature depending solely on the interactions among individuals without having any director fish. This kind of system can be said as the typical one of "Complex Systems". We make clear the validity of fractal analyses to evaluate fish school movements through evaluation of both the simulated movements and the real sardine movements taken by video tape. The analyses showed that we need two kinds of fractal dimensions (D$_1$, D$_2$) to fit to the observations; the one(D$_1$) corresponds to smaller coarsening levels and D$_2$ does to larger coarsening levels. The double linear analyses in ...

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.4
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• pp.192-198
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• 2012

Switch losses directly affect the efficiency of power conversion systems and those have big differences according to the power consumed by load systems and the structures of power conversion circuits. In this paper, analyses for switch losses in DC link converter are performed based on the circuit structures of the DC/DC converter in photovoltaic generation system whose output power is varied according to the amount of solar radiation, temperature and partial shade on the solar modules. Boost converter is adopted as a DC link converter topology of the photovoltaic generation system and the loss analyses for the switches used in the boost converters are performed according to the circuit structures. Analyses like the things performed in this paper will be a prerequisite to designing the photovoltaic generation system whose output power is changed according to the environmental variations.

• Structural Engineering and Mechanics
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• v.3 no.2
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• pp.145-162
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• 1995

A damped trapezoidal rule method for numerical time-integration is presented, and its application in analyses of dynamic response of damped structures is discussed. It is shown that the damped trapezoidal rule method has features that make it an attractive approach for applications in dynamic analyses of structures. Accuracy and stability analyses are developed for the damped single-degree-of-freedom systems. Error analyses are also performed for the Newmark beta method and compared with the damped trapezoidal rule method as a basis for discussion of the relative merits of the proposed method. The procedure is fully explicit and easy to implement. However, since the method is an explicit method, it is conditionally stable. The methodology is applied to several example problems to illustrate its strengths, limitations and inherent simplicity.