• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.203-205
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• 2002

This paper presents the fault location estimation algorithm in transmission line using a recursive least square error method (RLSE). To minimize the computational burden of the digital relay a RLSE approach is used. Computer simulation results of the RLSE algorithm seem promising, indicating that it should be considered for further testing and evaluation.

• Communications for Statistical Applications and Methods
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• v.4 no.3
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• pp.929-941
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• 1997

In this paper, we propose the minimum risk estimator (MRE) and the approximate maximum likelihood estimator (AMLE) of the location and the scale parameters of the two-parameter exponential distribution with Type-II censoring. The MRE's can be derived by minimizing the mean squared error among the class of estimators which include some estimators as special cases. We show that the MRE's are more efficient than the other estimators of the scale and the location parameter in the terms of the mean squared error.

• IEIE Transactions on Smart Processing and Computing
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• v.2 no.4
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• pp.208-215
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• 2013

Early iterations of the existing Global Positioning System (GPS)-based or radio lateration technique-based vehicle localization algorithms suffer from flip ambiguities, forged relative location information and location information exchange overhead, which affect the subsequent iterations. This, in turn, results in an erroneous neighbor-vehicle map. This paper proposes an extended information overlap measure (EIOM) algorithm to reduce the flip error rates by exchanging the neighbor-vehicle presence features in binary information. This algorithm shifts and associates three pieces of information in the Moore neighborhood format: 1) feature information of the neighboring vehicles from a vision-based environment sensor system; 2) cardinal locations of the neighboring vehicles in its Moore neighborhood; and 3) identification information (MAC/IP addresses). Simulations were conducted for multi-lane highway scenarios to compare the proposed algorithm with the existing algorithm. The results showed that the flip error rates were reduced by up to 50%.

• The Transactions of the Korea Information Processing Society
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• v.7 no.1
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• pp.306-312
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• 2000

In this paper, the efficient architecture of small Reed-solomon architecture is suggested. Here, 3-stage pipeline is adopted. In decoding, error-location polynomials are obtained by BMA using fast iteration method, and syndrome polynomials, where calculation complexity is required, are obtained by parallel calculation using ROM table, and the roots of error location polynomial are calculated by ROM table using Chein search algorithm. In the suggested decoder, it is confirmed that 3 symbol random errors can be corrected and 124Mbps decoding rate is obtained using 25 Mhz system clock.

• Journal of Digital Convergence
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• v.14 no.5
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• pp.301-307
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• 2016

The location measurement technique of moving worker in dangerous areas, is necessary for safety in the mines, basements, warehouses, etc. There are various measurement techniques about moving node of position in a restricted environment. Trigonometric Method, one of measurement techniques, is commonly used because of its easiness. However, errors occur frequently when measuring distance and position due to radio interference and physical disability with measuring instruments. This paper proposed a method which is more accurate and shows reduced margin of error than existing trigonometric method by recalculating distance between Anchor and moving node with various measuring instruments. By adding Anchor when calculating distance and position of moving node's estimated point, suggested technique obtains at least 41% efficiency compared to existing method.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.3
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• pp.13-18
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• 2015

This paper proposes an optimum vision system analysis and a reliable high-precision positioning system that converges a GNSS and a vision system in order to resolve position error and outdoor shaded areas two disadvantages of GNSS. For location determination of the object, it should receive signal from at least four GNSS. However, in urban areas, exact location determination is difficult due to factors like high buildings, obstacles, and reflected waves. In order to deal with the above problem, a vision system was employed. First, determine an exact position value of a target object in urban areas whose environment is poor for a GNSS. Then, identify such target object by a vision system and its position error is corrected using such target object. A vehicle can identify such target object using a vision system while moving, make location data values, and revise location calculations, thereby resulting in reliable high precision location determination.

• Journal of Oriental Neuropsychiatry
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• v.32 no.4
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• pp.321-328
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• 2021

Objectives: To compare bone proportional cun and finger-breadth cun in the head area to clearly distinguish the anterior hairline. Methods: In this study, the head area was measured for 50 adult males and females in their 20s with normal hair condition. We compared bone proportional cun and finger-breadth cun in the head area and calculated the error by analyzing the difference between the actual location of the anterior hairline and the location measured with the two methods. Results: There was a significant difference between bone proportional cun and finger-breadth cun in the head area. The two methods showed significant difference from the actual location of the anterior hairline. In addition, as a result of calculating the error between the actual location of the anterior hairline and the location measured by the two methods, the finger-breadth cun had fewer errors than the bone proportional cun. Conclusions: The finger-breadth cun is better than the bone proportional cun as an alternative when it is difficult to find the anterior hairline.

• Journal of the Korean Solar Energy Society
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• v.29 no.2
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• pp.39-46
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• 2009

Heliostat, as a mirror system tracking the sun's movement, is the most important subsystem determining the efficiency of solar thermal power plant. Thus the accurate sun tracking performance under the various hazardous operating condition, is required. This study presents a methodology of development of the solar ray tracing technique and the application of it in the analysis of sun tracking error due to the heliostat geometrical errors. The geometrical errors considered here are the azimuth axis tilting error and the elevation axis tilting error. We first analyze the geometry of solar ray reflected from the heliostat. Then the point on the receiver, where the solar ray reflected from the heliostat is landed, is computed and compared with the original intended point, which represents the sun tracking error. The result obtained shows that the effect of geometrical error on the sun tracking performance is varying with time(season) and the heliostat location. It also shows that the heliostat located near the solar tower has larger sun tracking error than that of the heliostat located farther.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.2
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• pp.415-421
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• 2009

TOA(time-of-arrival) and TDOA(time-difference-of-arrival) positioning techniques are commonly used in many radio-navigation systems. From the literature, it is known that the position estimate and error covariance matrix of TDOA obtained by GN(Gauss-Newton) method is exactly the same as that of TOA when the error source of the range measurement is only an IID white Gaussian noise. In case of geo-location and indoor positioning, however, multi-path or NLOS(non-line-of-sight) error is frequently appeared in range measurements. Though its occurrence is random, the multipath acts like a bias for a stationary user if it occurs. This paper presents the comparisons of error characteristics between TOA and TDOA positioning in presence of multi-path or NLOS error. It is analytically shown that the position estimate of TDOA is exactly the same as that of TOA even when bias errors are included in range measurements with different magnitudes. By computer simulation, position estimation error and error distribution are analyzed in presence of range bias errors.

• Journal of Positioning, Navigation, and Timing
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• v.5 no.1
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• pp.1-9
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• 2016

Range-based wireless localization system must measure accurate range between a mobile node (MN) and reference nodes. However, non-line-of-sight (NLOS) error caused by the spatial structures disturbs the localization system obtaining the accurate range measurements. Localization methods using the range measurements including NLOS error yield large localization error. But filter-based localization methods can provide comparatively accurate location solution. Motivated by the accuracy of the filter-based localization method, a filter residual-based NLOS error estimation method is presented in this paper. Range measurement-based residual contains NLOS error. By considering this factor with NLOS error properties, NLOS error is mitigated. Also a process noise covariance matrix tuning method is presented to reduce the time-delay estimation error caused by the single dynamic model-based filter when the speed or moving direction of a MN changes, that is the used dynamic model is not fit the current dynamic of a MN. The presented methods are evaluated by simulation allowing direct comparison between different localization methods. The simulation results show that the presented filter is more accurate than the iterative least squares- and extended Kalman filter-based localization methods.