• Journal of the Korean Society for Precision Engineering
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• v.15 no.12
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• pp.14-20
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• 1998

Cutting fluid is a factor which has big effects on both machinability and environment in machining process. The loss of cutting fluids may be reduced by the optimization of machining parameters in process planning. In this study, the environmental impact of fluid loss is analyzed. The fluid loss models in milling process are constructed with the machining parameters. The models are utilized to obtain the optimal machining parameters to minimize the fluid loss. The factors with significant effects on the fluid loss are analyzed by ANOVA test. Finally, optimal parameters are suggested considering both machining economics and environmental impact. This study is expected to be used as a part of a framework for the environmental impact assessment of machining process.

• 유체기계공업학회:학술대회논문집
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• 1998.12a
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• pp.57-63
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• 1998

The performance of a centrifugal fan depends on the dimensional parameters of impeller, such as the inlet and exit diameter, area ratio, relative flow angles to the blade, and number of blades. These design parameters, however, are inter-related, so it is very difficult to identify the effect of each parameter to the fan performance. In this experimental study the effect of the design parameters on the performance of a small centrifugal impeller being used for vacuum cleaners are investigated. Total 30 shrouded impellers with 120mm diameter were tested and the results were non-dimensionalized to compare their performance.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.835-840
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• 2002

The purpose of this study is to analyze the reinforcement effect of the RC compressive member confined with carbon fiber sheets and to suggest better transverse confinement coefficient(k$_1$) than one's in the existing analysis equations. Showing amounts of CPS in terms of ratio of transverse reinforcement to cross-section, it comes to be possible to calculate the objective and quantitative reinforcement amounts and to estimate the overlapping length of CFS that can influence on all its confinement effect. The previous parameters were compared using the existing experimental test data, then analyzed for the merits and demerits of existing parameters through the coefficient of correlation(R). The proposed parameters were derived in such a way that established parameters and their combination were obtained from the analytical study and then determined by regression analysis using the previous test data.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.10
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• pp.1144-1150
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• 2009

This paper investigates the feasibility of the Bayesian discrete time approximation method to estimate the parameters of Weibull distributions of failures for two non-identical components connected in series system. A Bayesian model based on the discrete time approximation method is formulated to infer the Weibull parameters of two non-identical components with the failure data of the virtual tests. The study of this paper comes to a conclusion that the method is feasible only for some special cases under the given constraints on the concerned parameters.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.244-246
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• 2006

In this study, we search some parameters well-related to floating-sinking pulse by statistical analysis, because these pulses are frequently used in clinic. Pulse signals were acquired by 3D pulse analyzer and 30 subjects consist of 15 people diagnosed as floating pulse and 15 people diagnosed as sinking pulse by oriental doctors who have over 5 years clinical experience. Then, we made a representative beat template for each subject and, through a peak detection algorithm, we calculated several pulse parameters. To find the parameters related to floating-sinking pulse, we performed statistical testing with 17 parameters through the independence sampling, t-test. As a result, there is the biggest difference between pressure, the maximum pulse pressure, diastolic area(Ad) and float-sink data. (p < .05).

• Proceedings of the KSRS Conference
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• v.2
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• pp.543-546
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• 2006

NDVI has been very frequently used to estimate several biophysical parameters that are required for ecosystem models. Leaf area index (LAI), canopy closure, and biomass are among those biophysical parameters that are estimated by empirical relationship with NDVI. However, the type of remote sensing signals (raw DN value, at-sensor radiance, atmospherically corrected reflectance) used can vary the calculation of NDVI. In this study, we tried to attempt to compare the influence of NDVI linked with forest LAI for the watershed-scale ecosystem models to estimate evapotranspiration. Landsat ETM+ data were used to obtain various NDVI values over the study area in central Korea. The NDVI-based LAI and the resultant evapotranspiration estimation were greatly varied by the remote sensing signal applied.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.911-920
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• 2010

A closed-type erosion control dam were suggested as an effective method to protect from debris flow damages caused by seasonal rainstorm, typhoon, and local heavy rain. However, design method on a closed-type erosion control dam currently practiced in the engineering is not well established with respect to type of the dam, design parameters, maintenance and so forth. In this study, design parameters for closed-type erosion control dam were evaluated and the comparison of design parameters used in Korea and Japan was performed. Based on the results of this study, modification of design method for closed-type erosion control dam are recommended.

• Journal of Korea Game Society
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• v.2 no.2
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• pp.46-51
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• 2002

In this study, a real-time simulation method for the phenomena, which are too complex to be simulated during real-time computer games, was proposed based on the neural network. The procedure of proposed method is to 1) obtain correlation data between input parameters and output parameters by mathematical modeling, code analyses, and so on, 2) train the neural network with the correlation data, 3) and insert the trained neural network in a game program as a simulation module. For the case that the number of the input and output parameters is too high to be analyzed, a method was proposed to omit parameters of little importance. The method was successfully applied to severe accidents of nuclear power plants, reflecting that the method was very effective in real time simulation of complex phenomena.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.584-589
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• 1988

Tuning of digital STC parameters for the system with unknown and time varying parameters as well as delays presents many preconditions and difficulties. In order to eliminate these difficulties and to enhance STC control functions, the present study employs the metbod of expert control for STC and to implement it in nod-minimum phase plants. In this paper, implimedtation of the Expert STC for process control, STC. parameters is carried out by tuning systematically and by applying these parameters to non-minimum phase plant. This controller supervises a status of the plant, and robust control function for time delay or change of the plant is demonstrated by computer simulations.

• Proceedings of the KSPS conference
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• 2005.04a
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• pp.63-66
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• 2005

Sasang Constitution, one branch of oriental medicine, claims that people can be classified into four different 'constitutions:' Taeyang, Taeum, Soyang, and Soeum. This study investigates whether the classification of the 'constitutions' could be accurately made solely based on people's voice by analyzing the data from 46 different voices whose constitutions were already determined. Seven source-related parameters and four filter-related parameters were phonetically analyzed and the GMM(gaussian mixture model) was tried with the data. Both the results from phonetic analyses and GMM showed that all the parameters (except one)failed to distinguish the constitutions of the people successfully. And even the single exception, the bandwidth of F2, did not provide us with sufficient reasons to be the source of distinction. This result seems to suggest one of the two conclusions: either the Sasang Constitutions cannot be substantiated with phonetic characteristics of peoples' voices with reliable accuracy, or we need to find yet some other parameters which haven't been conventionally proposed.