• Journal of Ocean Engineering and Technology
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• v.13 no.4 s.35
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• pp.169-173
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• 1999

In this paper some modifications for Lu's inverse method of fairing process are presented. The object function is changed and additional constraints for hull curve foiling is proposed. The newly introduced minimizing object function is the sum of the distances between the two curve's positions at the same parameter values instead of the sum of the distances between two vertices. The new one is better to represent the physical meaning of the object function, the smaller differences between two curves. In ship hull fairing the end tangent of curve has to be fined in some cases, so the additional constraint is considered to preserve the direction of end tangent. The sample results are shown.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.1
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• pp.23-28
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• 2004

This paper proposes a sensor-fusion technique where the data sets for the previous moments are properly transformed and fused into the current data sets to enable accurate measurement, such as, distance to an obstacle and location of the service robot itself. In the conventional fusion schemes, the measurement is dependent on the current data sets. As the results, more of sensors are required to measure a certain physical parameter or to improve the accuracy of the measurement. However, in this approach, instead of adding more sensors to the system, the temporal sequence of the data sets are stored and utilized for the measurement improvement. Theoretical basis is illustrated by examples and the effectiveness is proved through the simulations. Finally, the new space and time sensor fusion(STSF) scheme is applied to the control of a mobile robot in an unstructured environment as well as structured environment.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.79.2-79.2
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• 2013

The distributions of Horizontal Branch (HB) star color, temperature, and mass encode a great deal of information on the stellar evolutionary and (possibly) dynamical processes taking place in Globular Clusters (GCs). An accurate physical modeling of the Red Giant Branch (RGB) mass-loss process is key to solving the so-called second parameter problem. In my poster I will present the most recent advancements of an analytical model for mass-loss along the RGB. The model predicts the HB mass distribution with remarkable accuracy over a sample of 4 GCs. These results were submitted as a paper to ApJ (Pasquato et al. 2013, ApJ submitted), but here I expand on them presenting refinements to the model and a comparison with HB masses obtained from Galex ultraviolet observations.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.420-425
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• 2001

The information content is determined by establishing the system range for each of the FRs and by determing the overlap between system range and the design range (i.e the designer-specified range). However, conventional information content doesn't include designer's intention sufficiently. In this paper, the satisfaction function is presented to embody designer's intention by calculating information contents. The satisfaction function is created in order to deal with the uncertanties involved in determining the design range and the system range in terms of a given physical parameter. So, the satisfaction function help designer to choose the optimal design among many proposed design.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.3
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• pp.55-67
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• 2009

This paper addresses the dynamic consideration of the athletic constraints on skating motion. In order to generate a human-like skating motion, the athletic constraints are distinctively analyzed into dynamic constraints and physical constraints. A close investigation of the athletic constraints evolved valid extent of dominant parameter for a leg muscle. During the human-like skating motion, the state of actuation was shifted from region of maximum force to region of maximum power. Simulation results were intuitively comprehensible, and the effectiveness of analytic algorithm was demonstrated for skating motion.

• Journal of Power System Engineering
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• v.3 no.4
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• pp.79-85
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• 1999

The magnetic levitation system is utilized in the magnetic bearing of high-speed rotor system because of little friction, no lubrication, no noise and so on. The magnetic levitation system needs the feedback controller for the stabilization of system, and gap sensors are generally used to measure the gap. The use of sensor easily goes into troublesome caused by sensor failure discord between the measurement point and the control point etc. This paper gives a controller design method of magnetic levitation system which satisfies the given $H_{\infty}$ control performance and the robust stability of the presence of physical parameter perturbations. To the end, we investigated the validity of the designed controller through results of simulation.

• Journal of Power System Engineering
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• v.21 no.3
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• pp.66-73
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• 2017

In order to identify the design parameters of a hydraulic engine mount with a nonlinear characteristics, an experimental method has been used generally. The method takes a considerable time and expense because of preparing an experimental apparatus, conducting a test, and analyzing results. Therefore, this paper presents a simple method to identify the design parameters of a cylindrical hydraulic engine mount, and optimize the design parameters. The physical model and mathematical equations of the mount were derived, and values of the design parameters of the mount were identified by optimization method with minimizing difference between the analytical results with the equations and the experimental results. This method is more simpler than the conventional experiment method and identify successfully the design parameters. In addition, the technique can optimize the design parameters of the mount to improves the isolation performance of the mount.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.553-558
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• 2002

Physical sensor model in pushbroom satellite images can be made from sensor modeling by rotation parameters and attitude parameters on the satellite track. These parameters are determined by the information obtained from GPS, INS, or star tracker. Provided from satellite image, an auxiliary data error is connected directly with an error of rotation parameters and attitude parameters. This paper analyzed how obtaining satellite images influenced errors of rotation parameters and attitude parameters. furthermore, for detailed analysis, this paper generated simulated satellite image, which was changed variously by rotation parameters and attitude parameters of satellite sensor model. Simulated satellite image is generated by using high-resolution digital aerial image and DEM (Digital Elevation Model) data. Moreover, this paper determined correlation of rotation parameter and attitude parameters through error analysis of simulated satellite image that was generated by various rotation parameters and attitude parameters.

• Journal of environmental and Sanitary engineering
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• v.10 no.3
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• pp.56-66
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• 1995

To investigate environmental impacts of inland fish- farms on the water quality of a stream, environmental parameters including physical, chemical and biological factorswere estimated at trount- farm in 1994. Influences( F-1) were polluted as passing through fish tank( F-2) and settle pond( F-3), so organic and inorganic nutrient concentrations became very high in effluents( F-4). BOD$_{5}$, Chl. a, Nitrite and heterotrophic bacterial numbers in the junction site(5-2) of F-4 and S-1( upstream) were highest among the stream sites. BOD$_{5}$ was proved to a good parameter of organic pollution, and nitrite of Inorganic nutrients in the fishery and it's affected stream, The high concentration of BOD$_{5}$ and Chl. a in S-2 were decreased in downstream(5-3, 5-4). It seems that this results are due to dilution or sedimentation effect. This supposition requires further testing about the sediment of stream. The results of this paper demonstrate that fish farming can deteriorate water quality of a stream by changing environmental factors.

• Journal of Korean Society of Water and Wastewater
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• v.9 no.4
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• pp.63-72
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• 1995

The mean velocity gradient, G, has been used as a principal design and operation parameter for flocculation unit. This paper questions that significance. The physical and qualitative meaning of collision efficiency factors of each transport mechanism (Brownian motion, fluid shear, and differential sedimentation) are reviewed. The overall collision frequency function is calculated by summing up the collision frequency function of each mechanism. In the collision of two particles of different size, a diagram showing the dominant region in which each mechanism is important is developed and the meaning of the diagram is discussed. The primary ramification of this curvilinear, heterodisperse approach is that G is found to be not nearly so important. Previous experimental work in which the role of G has been examined is reviewed in light of this finding.