• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.401-406
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• 1992

When a velocity-aided strapdown inertial navigation system is loaded into a torpedo subjected to an extraneous force by the current, odometer measurement errors occur seriously. In order to compensate for navigation errors induced by large odometer biases, the Kalman Filter with separate bias estimator is applied, which separately estimates an unknown bias, and corrects the state estimate produced by the bias-free Kalman Filter to reflect the effect of the bias estimate.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.11
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• pp.1117-1124
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• 2010

This paper presents a foot movement tracking system using ultrasonic sensors and inertial sensors, where the position and velocity of foot are computed using inertial sensors and ultrasonic sensors mounted on a shoe. A foot movement can be estimated using an inertial navigation algorithm only; however, the error tends to increase due to biases of gyroscopes and accelerometers. To reduce the error, a localization system using ultrasonic sensors is additionally used. In the localization system using ultrasonic sensors, the position is continuously calculated in the absolute coordinate. An indirect Kalman filter is used to combine inertial sensors and ultrasonic sensors. Through experiments, it is shown that the proposed system can track a foot movement.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.30.2-30.2
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• 2010

A direct tilted-ring fitting method allows us to investigate kinematic structure of spiral galaxies. By employing the method to high-resolution HI data cubes, we can more easily trace warp characteristics of spiral galaxies than ever. In this contribution, we make use of TiRiFiC to VLA HI data cube of spiral galaxies in Virgo cluster, and present our preliminary yet interesting results. The TiRiFiC (Tilted-Ring-Fitting-Code) is publicly available code that provides 'best-fit' tilted-ring parameters (i.e. position angle and inclination) via chi-square minimization technique. We also discuss possible biases (e.g., resolution dependency) and its effect on our conclusions.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.38.1-38.1
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• 2018

With upcoming high-quality data from surveys such as eBOSS or DESI, improving the theoretical modeling and gaining a deeper understanding of the effects of neutrinos and dark radiation on structure formation at small scales are necessary, to obtain robust constraints free from systematic biases. Using a novel suite of hydrodynamical simulations that incorporate dark matter, baryons, massive neutrinos, and dark radiation, we present a detailed study of their impact on Lyman-Alpha forest observables. In particular, we accurately measure the tomographic evolution of the shape and amplitude of the small-scale matter and flux power spectra and search for unique signatures along with preferred scales where a neutrino mass detection may be feasible. We then investigate the thermal state of the intergalactic medium (IGM) through the temperature-density relation. Our results indicate that the IGM at z ~ 3 provides the best sensitivity to active and sterile neutrinos.

• Korean Journal of Child Studies
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• v.22 no.2
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• pp.329-346
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• 2001

This analysis of the portrayal of characters in 74 picture books used in kindergarten focused on the gender types and roles of girls and boys, adult females, adult males, and feminist perspectives or sexism. Results showed that girls were rewarded according to their abilities and accomplishments, and they were considered to have equal rights; boys were depicted as dominant, positive, logical, courageous and having initiative; adult females, especially mothers at home, were responsible exclusively for housekeeping and child rearing; adult males, including fathers, were depicted as dominant characters in a variety of professional occupations and social activities, nonetheless, in many books, children were depicted as androgynous personalities having human rights. Though these results show changes in gender stereotypes from the 1970s and 1980s, subtle biases of gender still remain in children's books.

• JSTS:Journal of Semiconductor Technology and Science
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• v.4 no.1
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• pp.18-26
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• 2004

Back-gated silicon-on-insulator MOSFET -a threshold-voltage adjustable device-employs a constant back-gate potential to terminate source-drain electric fields and to provide carrier confinement in the channel. This suppresses shortchannel effects of nano-scale and of high drain biases, while allowing a means to threshold voltage control. We report here a theoretical analysis of this geometry to identify its natural length scales, and correlate the theoretical results with experimental device measurements. We also analyze experimental electrical characteristics for misaligned back-gate geometries to evaluate the influence on transport behavior from the device electrostatics due to the structure and position of the back-gate. The backgate structure also operates as a floating-gate nonvolatile memory (NVRAM) when the back-gate is floating. We summarize experimental and theoretical results that show the nano-scale scaling advantages of this structure over the traditional front floating-gate NVRAM.

• Earthquakes and Structures
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• v.4 no.5
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• pp.527-555
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• 2013

This paper proposes probabilistic models for estimating the seismic demands on reinforced concrete (RC) bridges with base isolation. The models consider the shear and deformation demands on the bridge columns and the deformation demand on the isolation devices. An experimental design is used to generate a population of bridges based on the AASHTO LRFD Bridge Design Specifications (AASHTO 2007) and the Caltrans' Seismic Design Criteria (Caltrans 1999). Ground motion records are used for time history analysis of each bridge to develop probabilistic models that are practical and are able to account for the uncertainties and biases in the current, common deterministic model. As application of the developed probabilistic models, a simple method is provided to determine the fragility of bridges. This work facilitates the reliability-based design for this type of bridges and contributes to the transition from limit state design to performance-based design.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.263-267
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• 2001

Beef samples of loin eye area from New Zealand, USA and three quality grades of Hanwoo were analyzed using near infrared spectrophotometer with reference values from laboratory optical Chromameter to determine effective spectrum range and mathematical treatment for determination of color values. $R^2s$ of prediction models were not improved much by calibrating with whole light range (400~2500 nm) compared to using visible range (400~1100 nm). Standard errors of calibration and prediction were influenced by possible bias due to sampling non-homogeneous sample sources. However, partial differentiation in the first order was more stable against sampling biases than second derivatives of the spectra. Lightness value was little different among the five sample sources of beef. Beef samples from USA were brighter and more reddish than beefs of Hanwoo or from New Zealand (p<0.05). Yellowness of USA beef was the highest followed by beef from New Zealand, which was also higher than Hanwoo beefs of three quality grades (p<0.05).

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.4 s.23
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• pp.14-23
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• 2005

In this paper we propose a sensor fusion method for the navigation algorithm which can be used to estimate state vectors such as position and velocity for its motion control using multi-sensor output measurements. The output measurement we will use in estimating the state is a series of known multi-sensor asynchronous outputs with measurement noise. This paper investigates the Extended Kalman Filtering method to merge asynchronous heading, heading rate, velocity of DVL, and SSBL information to produce a single state vector. Different complexity of Kalman Filter, with. biases and measurement noise, are investigated with theoretically data from MOERI's SAUV. All levels of complexity of the Kalman Filters are shown to be much more close and smooth to real trajectories then the basic underwater acoustic navigation system commonly used aboard underwater vehicle.

• The KIPS Transactions:PartB
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• v.10B no.6
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• pp.593-598
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• 2003

Machine learning organizes knowledge for efficient and accurate reuse. This paper is concerned with methods of concept learning from examples, which glean knowledge from a training set of preclassified ‘objects’. Ideally, training facilitates classification of novel, previously unseen objects. However, every learning system relies on processing and representation assumptions that may be detrimental under certain circumstances. We explore the biases of a well-known learning system, ID3, review improvements, and introduce some improvements of our own, each designed to yield accurate and pedagogically sound classification.