• International Journal of Control, Automation, and Systems
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• v.3 no.3
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• pp.430-443
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• 2005

A general construction algorithm of the Grassmann space parameters in linear systems - so-called, the Plucker matrix, 'L' in m-input, p-output, n-th order static output feedback systems and the Plucker matrix, $'L^{aug}'$ in augmented (m+d)-input, (p+d)-output, (n+d)-th order static output feedback systems - is presented for numerical checking of necessary conditions of complete static and complete minimum d-th order dynamic output feedback pole-assignments, respectively, and also for discernment of deterministic computation condition of their pole-assignable real solutions. Through the construction of L, it is shown that certain generically pole-assignable strictly proper mp > n system is actually none pole-assignable over any (real and complex) output feedbacks, by intrinsic rank deficiency of some submatrix of L. And it is also concretely illustrated that this none pole-assignable mp > n system by static output feedback can be arbitrary pole-assignable system via minimum d-th order dynamic output feedback, which is constructed by deterministic computation under full­rank of some submatrix of $L^{aug}$.

• The Journal of the Convergence on Culture Technology
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• v.4 no.4
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• pp.309-316
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• 2018

In this study, we propose a 3D virtual reality based presentation training system to help implement the virtual presentation environment, such as the real world, to present it confidently in the real world. The proposed system provided a realistic and highly engaging presentation and interview environment by analyzing the speakers' voice and behavior in real time to be reflected in the audience of the virtual space. Using HMD and VR Controller that become 6DOF Tracking, the presenter can change the timing and interaction of the virtual space using Kinect, and the virtual space can be changed to various settings set by the user. The presenter will look at presentation files and scripts displayed in separate views within the virtual space to understand the content and master the presentation.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.4
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• pp.543-552
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• 1996

The goal of this paper is to developed a DSP based power analyzing and control system by 3-Dimensional (3-D) space current co-ordinates. A developed system is made up of 486-PC and DSP (Digital Signal Processor) board, Active Power Filter, Non-linear thyristor load, and Power analyzing and control program for Windows. Power is analyzed using signal processing techniques based on the correlation between voltage and current waveforms. Since power analysis algorithm is performed by DSP, power analysis is achieved in real-time even under highly dynamic nonlinear loading conditions. Combining control algorithm with power analysis algorithm is performed by DSP, power analysis is achieved in real-time even under highly dynamic nonlinear loading conditions. Combining control algorithm with power analysis algorithm, flexibility of the proposed system which has both power analysis mode and control mode, is greatly enhanced. Non-active power generated while speed of induction motor is controlled by modulating firing angle of thyristor converter, is compensated by Active Power Filter for verifying a developed system. Power analysis results, before/after compensation, are numerically obtained and evaluated. From these results, various graphic screens for time/frequency/3-D current co-ordinate system are displayed on PC. By real-time analysis of power using a developed system, power quality is evaluated, and compared with that of conventional current co-ordinate system. (author). refs., figs. tabs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.1
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• pp.80-86
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• 2013

The 3-Dimensional(3D) localization system based on beacon expansion and coordinate-space disassembly for the design of the 3D localization system in indoor environment is proposed and the performance of the proposed system is analyzed in this paper. The localization ratio of the 3D localization system adapts the proposed algorithm is analyzed by the calculation of errors occurred in the coordinates that the mobile node locates. It is indicated that the average error distance of the 3D localization system adapts the proposed algorithm is less than that of the 3D localization system not adapts the proposed algorithm as 0.47m. The localization average distance error in 12 coordinates is indicated that the 1.5m case is less than 2.5m case as 0.38m by some experimentations under the condition that the distances between the ceiling and the mobile node are 1.5m and 2.5m measured from the ceiling respectively. It is seen that the 3D localization system based on beacon expansion and coordinate-space disassembly can improved the degradation of the quality of service that is caused by some conditions and performance differences in sensors.

• Journal of Astronomy and Space Sciences
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• v.29 no.4
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• pp.329-336
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• 2012

Korea Astronomy and Space Science Institute researchers have installed and operated magnetometers at Bohyunsan Observatory to measure the Earth's magnetic field variations in South Korea. In 2007, we installed a fluxgate magnetometer (RFP-523C) to measure H, D, and Z components of the geomagnetic field. In addition, in 2009, we installed a Overhauser proton sensor to measure the absolute total magnetic field F and a three-axis magneto-impedance sensor for spectrum analysis. Currently three types of magnetometer data have been accumulated. In this paper, we use the H, D, Z components of fluxgate magnetometer data to investigate the characteristics of mid-latitude geomagnetic field variation. To remove the temporary changes in Earth's geomagnetic filed by space weather, we use the international quiet days' data only. In other words, we performed a superposed epoch analysis using five days per each month during 2008-2011. We find that daily variations of H, D, and Z shows similar tendency compared to previous results using all days. That is, H, D, Z all three components' quiet intervals terminate near the sunrise and shows maximum 2-3 hours after the culmination and the quiet interval start from near the sunset. Seasonal variations show similar dependences to the Sun. As it becomes hot season, the geomagnetic field variation's amplitude becomes large and the quiet interval becomes shortened. It is well-known that these variations are effects of Sq current system in the Earth's atmosphere. We confirm that the typical mid-latitude geomagnetic field variations due to the Sq current system by excluding all possible association with the space weather.

• The Journal of the Korea Contents Association
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• v.12 no.8
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• pp.264-273
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• 2012

The purpose of this study was to determine the test-retest reliability and the concurrent validity between tinetti mobility test (TMT), berg balance scale (BBS) and space balance 3D which is one of the computerized measurement and visual feedback balance assessment system in subacute stroke patients. Twenty three ambulatory acute stroke subjects were measured the TMT, BBS and space balance 3D. The test-retest reliability(intra-class correlation coefficient: ICC) indicated that the static and dynamic balance in space balance 3D considered moderate reliability and TMT, BBS were good reliability. In case of concurrent validity, there were moderate validity (p<.01) between static balance test with space balance 3D and each TMT, BBS. But there were only poor validity (p<.05) between center to forward-left, center to backward-left phase in dynamic balance test with space balance 3D and each TMT, BBS. These findings suggest that in subacute stroke patients the test-retest reliability and concurrent validity using the space balance 3D and TMT were valuable in balance test but there was limitation to evaluate dynamic balance test.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.9
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• pp.609-616
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• 2022

The performance of antenna reflectors crucially depends on the faceting error of the surface. The force density method (FDM) has been widely used for the form-finding analysis of the cable nets of reflectors. However, after performing form-finding of some cable nets, the effective reflective area will decrease. In addition, nonlinear deformations of the cable can not be achieved by using the FDM. Thus, an effective form-find methodology is proposed in this research. The whole parts of the cable networks are described by the absolute nodal coordinate formulation. The form-finding analysis of the reflector with standard configuration is performed to validate the proposed methodology. The influence of boundary condition changes on the configuration accuracy of the cable net is investigated.

• 한국디지털정책학회:학술대회논문집
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• 2006.12a
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• pp.409-418
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• 2006

The purpose of this paper is to present a low cost u-City portal development idea and to propose an exclusive system architecture using 3-D interface layers. 3-D interface layers consist of reused ideas of data from existed public data produced from GIS in order to reduce Produce Processes. 3-D interface layers implement a u-City portal systems that tags from physical spaces 1 ink to mobiles from ubiquitous networks between electronic spaces and physical spaces. Primary produce of this study exhibits an exclusive architecture of a u-City portal for speedy and low cost web 3-D interface layers and GIS data, and for implementation interface of 3-D types on USN of physical spaces. Secondary produce of this study represents that a 3-D u-City portal system has visualized speedy implementation characteristics for implementation of the application systems to execute an ubiquitous concept by returning electronic space to physical space, and to present the low cost 3-D u-City portal than an existed 3-D u-city development strategy. Therefore continuous expansion and study of the 3-D interface physical space under a 상황인지(Context Awareness)ubiquitous will appear the innovated u-City portal systems.

• Bulletin of the Korean Space Science Society
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• 2011.04a
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• pp.30.1-30.1
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• 2011

We present construction of 3D Earth optical Model for in-orbit performance prediction of L1 halo orbiting earth remote sensing instrument; the Albedo Monitor and Radiometer (Amon-Ra) using Integrated Ray Tracing (IRT) computational technique. The 3 components are defined in IRT; 1) Sun model, 2) Earth system model (Atmosphere, Land and Ocean), 3)Amon-Ra Instrument model. In this report, constructed sun model has Lambertian scattering hemisphere structure. The atmosphere is composed of 16 distributed structures and each optical model includes scatter model with both reflecting and transmitting direction respond to 5 deg. intervals of azimuth and zenith angles. Land structure model uses coastline and 5 kinds of vegetation distribution data structure, and its non-Lambertian scattering is defined with the semi-empirical "parametric kernel method" used for MODIS (NASA) missions. The ocean model includes sea ice cap with the sea ice area data from NOAA, and sea water optical model which is considering non-Lambertian sun-glint scattering. The IRT computation demonstrate that the designed Amon-Ra optical system satisfies the imaging and radiometric performance requirement. The technical details of the 3D Earth Model, IRT model construction and its computation results are presented together with future-works.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.437-439
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• 2002

Tangible user interfaces have attracted strong attention in the HCI(Human and Computer Interface) community for their ability to take advantage of skills humans develop in the real world. We are developing "tangible media aided design system" which employs physical objects i.e., brick as interfacing media for 3D graphic modeling. This system is targeting for persons who are afraid of experiencing 3D graphic modeling and virtual space, or have a sense of reluctance in approaching to them. Our approach suggests the easiest way for people to experience computer system and virtual space carefree while developing and improving their space sense. This work is one of initial explorations of media aided design system using tangible user interfaces.