• Journal of the Korean Society of Combustion
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• v.6 no.2
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• pp.29-35
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• 2001

Unsteady numerical study has been conducted on combustion dynamics of a lean-premixed swirl-stabilized gas turbine swirl injector. A three-dimensional computation method utilizing the message passing interface (MPI) parallel architecture, large eddy simulation(LES), and proper orthogonal decomposition (POD) technique was applied. The unsteady turbulent flame dynamics are simulated so that the turbulent flame structure can be characterized in detail. It was observed that some fuel lumps escape from the primary combustion zone, and move downstream and consequently produce hot spots. Those flame dynamics coincides with experimental data. In addition, basis modes of the unsteady turbulent flame are characterized using proper orthogonal decomposition (POD) analysis. The flame structure based on odd basis modes is apparently larger than that of even ones. The flame structure can be extracted from the summation of the basis modes and eigenvectors at any moment.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1992.04a
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• pp.51-57
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• 1992

The primary objective of this study is the development of second moment methods for the efficient reliability evaluations of structural systems. Two methods are presented. One is the improved first order reliability method (IFORM), and the other is the modified probabilistic network evaluation technique (MPNET). For the purpose of verifying the proposed methods, example analyses are carried out on several cases with two failure modes, a plane frame structure involving three failure modes and simplified parallel member models for fatigue reliability evaluations of offshore structures. Numerical results indicate that the effectiveness of the proposed methods over the conventional ones (i.e., the FORM and the PNET) increases very significantly as the number of failure modes of the system increases.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1989.10a
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• pp.34-39
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• 1989

Recent trends in design standards development have encouraged the use of probabilistic limit sate design concepts. Reliability analysis adopted in those advanced countries have the potentials that they afford for symplifying the design Process arid placing it on a consistent reliability based for various construction materials. This study is proposed in the reliability analysis of plane frame structures using second-order moment method(Level-II they). Lind-Hasofer's minimum distance method is use in the derivation of an mathematical algorithm as well as an determination of Correlation cofficients, reliability index and total reliability index depending on the multiple failure modes. In addition. This study is employed as a practical tool for the approximate reliability analysis. Results of the numerincal analysis showed that the difference between the reliability index of the failure probability of the multiple failure modes and the total reliability index of the failure probability with the simultaneous failure modes deviated nearly 3∼10% depending on tile performance functions.

• Korean Journal of Child Studies
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• v.15 no.2
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• pp.69-96
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• 1994

The purpose of this study was to develop an inventory for measuring verbal control modes of korean parent. The subjects of this study were 332 children of fifth and sixth grade in elementary schools located in Seoul. Forty seven questions were developed, of which 24 were collected from other previous studies and 23 were newly developed by the researcher and each question was composed of 3 items. The 141 items (47 questions x 3 items) were analyzed by the statistical methods of item analysis, principal factor analysis. The resulting inventories composed of 28 (84 items) and 29 (87 items) questions assess the three types of verbal control modes of both mothers and fathers: imperative control, position-oriented control and person-oriented control. Internal consistency of the scale was high (Cronbach's= .91-.95). Factor validity was also satisfactory (.66-.87).

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.6
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• pp.117-124
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• 2002

For the correct estimation of air pollutant emission from automobiles which is the largest contributor of metropolitan area air pollution, the total pollutant emission from automobiles should be estimated accurately. Nationwide emissions from automobiles, such as CO, HC and NOx, are calculated by using emission factor and total VMT(vehicle miles traveled). The emission factors were derived from the emissions data on chassis dynamometer with test modes which represent the real driving patterns. In the present study, test modes to derive the emission factors for light duty vehicles are developed by using the real driving pattern data for the urban, suburban and express way.

• Proceedings of the KSR Conference
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• 2002.05a
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• pp.437-445
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• 2002

The development of railway vehicle and bogie involves the proper selection of design parameters not only to achieve high speed of the train but also to reduce the vibration. In this study, an analytical model of a high speed freight car is developed to find the critical speed. The high speed freight car can generate the snake motion of the lateral, rolling and yawing motion of the car body and the bogie. The numerical analysis for the equation motions with 17 degrees of freedom showed the running stability and the critical speed due to the snake motion. Also the vibration modes of the high speed freight car was calculated using ADAMS RAIL software, which showed that the critical speed have the yawing modes of the car body and the bogie.

• Korea Multimedia Society
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• v.1 no.1
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• pp.19-32
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• 1997

There are many kinds of predominant modes to transfer Multimedia information on internet in the world. Various methods are applied to get real time multimedia data as possible as we need. At the moment it is very difficult to use acceptable technologies for performe those methods effectively on the Networks. This paper gives the alternative directions and trends for research and development of multimedia transmission on the internet. ATM is one of the best mode to transfer mass-multimedia data at the high speed on the Broad-Band ISDN until now. And xDSL (xDigital Subscriber Line) is an excellent typical method on the PSTN (Public Switched Telephone Network) using old type telephone line. But they are not yet applied into the phase of practical use together this time. So this paper analyzes what we need and how to develop the multimedia transmission modes which we can send on the internet without a problem or any difficulty for our various multimedia information all the time under low cost and high speed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.11
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• pp.955-962
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• 2016

In recent years, there have been emerging needs for standardized software-based motion application development for better scalability and support for multiple operation modes for small quantity batch production. Although a software-based motion system provides a basis for constructing multiple operation modes on a machine, it is not easy to construct such systems without tools for defining multiple motion operation modes and standardized mode-change protocols. This paper proposes a motion recipe concept to overcome this problem; the concept includes the authoring of multiple motion operation modes using the PLCopen-compliant motion function blocks and communication protocols to trigger operation mode changes from an external interface. The motion recipe was implemented by extending an IEC 61131-3 compliant IDE called Beremiz, and the correctness of the motion recipe-based application behavior was verified on a real testbed.

• Journal of Industrial Technology
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• v.24 no.A
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• pp.119-126
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• 2004

BLDC Motor is one of the widely utilizable motors in servo system. The accurate calculation of the power loss for the IGBT and Inverse diode with Bipolar and Unipolar switching modes the driving modes is important for the design of drives for their heat treatment. If it were not for temperature-sensors in devices, it is difficult to get direct power loss, so. Power losses may be modeled by computer modeling to obtain the Calculation of the Power loss for Inverter in BLDC Motor with switching modes which is presented in this paper. The computer modeling is carried out by Matlab simulation. The power loss consists of conduction losses Conduction losses are the source of occurrence due to The IGBT and Inverse diode currents. Switching losses are the source of occurrence due to switching on/off in the devices, and gives the dominant influence to the loss. As a result, the unipolar I mode is best in reducing the heat losses.

• STI Policy Review
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• v.5 no.2
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• pp.20-42
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• 2014

The Brazil, Russia, India China and South Africa (BRICS) group has emerged as a collection of large economies which are outside the traditional groups of industrialised "first world" economies and which have altered the global distribution of economic power. The basis of their emergence is a combination of their size and growth rates, and the fact that they lie outside the established centres of global economic power. As such, they have "diversified" the power base of the global economic order. The question which is asked in this paper is whether the phenomenon of the BRICS goes beyond this to mark the start of a possible challenge to the neoliberal orthodoxy which emerged as the globally dominant policy paradigm since the collapse of the Soviet Union. This paper develops and uses a "modes of innovation" approach to explore the potential of the BRICS to constitute a structural rupture in the current globally dominant neoliberal mode of innovation. This question is important since, in the absence of this rupture, the remarkable development trajectory of the BRICS will serve to reinforce the legitimacy of the global orthodoxy. The paper first articulates the modes of innovation concept and then proceeds to locate the BRICS systems of innovation within the current globally dominant mode. On this basis it then provides an appraisal of the possible impact of the BRICS on the evolutionary path of the global system of innovation.