• Atmosphere
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• v.33 no.1
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• pp.33-47
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• 2023

In this study, for the application of observation errors to the Korean Integrated Model (KIM) to utilize the Constellation Observing System for Meteorology, Ionosphere & Climate-2 (COSMIC-2) new satellites, the observation errors were diagnosed based on the Desroziers method using the cost function in the process of variational data assimilation. We calculated observation errors for all observational species being utilized for KIM and compared with their relative values. The observation error of the calculated the Global Navigation Satellite System Radio Occultation (GNSS RO) was about six times smaller than that of other satellites. In order to balance with other satellites, we conducted two experiments in which the GNSS RO data expanded by about twice the observation error. The performance of the analysis field was significantly improved in the tropics, where the COSMIC-2 data are more available, and in the Southern Hemisphere, where the influence of GNSS RO data is significantly greater. In particular, the prediction performance of the Southern Hemisphere was improved by doubling the observation error in global region, rather than doubling the COSMIC-2 data only in areas with high density, which seems to have been balanced with other observations.

• Korean Institute of Interior Design Journal
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• v.20 no.3
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• pp.135-142
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• 2011

There occurs subtle shaking in our eyes while in looking at objects and this study sets up the standard of reconciliation from the property of observation and organizes the property of data reconciliation by the observation range to secure the feasibility of reconciliation range and method of the original data obtained from observation experiment and its analysis process. The results from above study can be concluded as in the followings: First, it made clear the process to exclude eye blink and data out of image range from the original data so to set up the range of available data. Second, on the basis of existing theory, it was possible to define the minimum attention time as 0.1 second (3 times of observation) and the visual understanding time of space as 0.3 second (9 times of observation) in the study on the property of observation, and this definition of observation time of sight fixation becomes an important indicator in the analysis of observation data. Third, based on the observation theory of continuity securing and attention, it was able to arrange the standard of reconciliation by carrying out reconciliation works only when fixed data with more than three times of observation showed consecutively before and behind the data with intermittent movements. Fourth, In the sector whether visual understanding occurred (more than 9 times), it increased by 12% for the frequency of observation and by 7.8% for the times of observation compared with the ones before the reconciliation. These results showed to have a constant change by subjects so that it was able to arrange a foundation to secure objective data in the analysis of the observation range and its extent.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.4
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• pp.964-969
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• 2008

This paper proposes a HMM-based recognition method using DMSVQ(Dynamic Multi-Section Vector Quantization) codebook by DMS(Dynamic Multi-Section) model and fuzzy concept, as a study for speaker- independent speech recognition. In this proposed recognition method, training data are divided into several dynamic section and multi-observation sequences which are given proper probabilities by fuzzy rule according to order of short distance from DMSVQ codebook per each section are obtained. Thereafter, the HMM using this multi-observation sequences is generated, and in case of recognition, a word that has the most highest probability is selected as a recognized word. Other experiments to compare with the results of recognition experiments using proposed method are implemented as a data by the various conventional recognition methods under the equivalent environment. Through the experiment results, it is proved that the proposed method in this study is superior to the conventional recognition methods.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.28B no.12
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• pp.68-74
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• 1991

This paper proposes a HMM model based on fuzzy, as a method on the speech recognition of speaker-independent. In this recognition method, multi-observation sequences which give proper probabilities by fuzzy rule according to order of short distance from VQ codebook are obtained. Thereafter, the HMM model using this multi-observation sequences is generated, and in case of recognition, a word that has the most highest probability is selected as a recognized word. The vocabularies for recognition experiment are 146 DDD are names, and the feature parameter is 10S0thT LPC cepstrum coefficients. Besides the speech recognition experiments of proposed model, for comparison with it, we perform the experiments by DP, MSVQ and general HMM under same condition and data. Through the experiment results, it is proved that HMM model using fuzzy proposed in this paper is superior to DP method, MSVQ and general HMM model in recognition rate and computational time.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.580-585
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• 2005

A QRT(Quad-Rotor Type) hovering robot system is developed for quick detection and observation of the circumstances under calamity environment such as indoor fire spots. The UAV(Unmanned Aerial Vehicle) is equipped with four propellers driven by each electric motor, an embedded controller using a DSP, INS(Inertial Navigation System) using 3-axis rate gyros, a CCD camera with wireless communication transmitter for observation, and an ultrasonic range sensor for height control. The developed hovering robot shows stable flying performances under the adoption of RIC(Robust Internal-loop Compensator) based disturbance compensation and the vision based localization method. The UAV can also avoid obstacles using eight IR and four ultrasonic range sensors. The VTOL(Vertical Take-Off and Landing) flying object flies into indoor fire spots and sends the images captured by the CCD camera to the operator. This kind of small-sized UAV can be widely used in various calamity observation fields without danger of human beings under harmful environment.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.11
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• pp.9-21
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• 2009

This paper proposes the alternative observer and controller design scheme based on T-S fuzzy model. Nonlinear systems are represented by fuzzy models since fuzzy logic systems are universal approximators. In order to estimate the unmeasurable states of a given unknown nonlinear system, T-S fuzzy modeling method is applied to get the dynamics of an observation system. T-S fuzzy system uses the linear combination of the input state variables and the modeling applications of them to various kinds of nonlinear systems can be found. The proposed indirect adaptive fuzzy observer based on T-S fuzzy model can cope with not only unknown states but also unknown parameters. The proposed controller is based on a simple output feedback method. Therefore, it solves the singularity problem, without any additional algorithm, which occurs in the inverse dynamics based on the feedback linearization method. The adaptive fuzzy scheme estimates the parameters and the feedback gain comprising the fuzzy model representing the observation system. In the process of deriving adaptive law, the Lyapunov theory and Lipchitz condition are used. To show the performance of the proposed observer and controller, they are applied to an inverted pendulum on a cart.

• Korean Institute of Interior Design Journal
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• v.18 no.5
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• pp.128-136
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• 2009

This study analyzed and defines the property of visual perception throughout the revision of the observation time of the original space and the rotating space. The conclusions of this study are as fellows: First, based on the existing theory and experiment, the study obtained the basis which decides the sector data originating fixation-gaze after staring the specific sector over 300ms time. It will become the turning point hereafter for our research to fix the time in this way. Second, in analyzing the minute data, the study built a revision method of the observation time by analyzing the meanings and the reasons of the revision of the original data. Third, according to the difference of revision quantity, female testee have more increases in the amount of data than male testee from the original screen. On the other hand, the opposite tendency appears from the previous data. This shows there is a difference in the observation properly by sex. Last, we could grasp Information about the property of the observation time throughout eyeball fixations, and the revision and analysis of the 'controlled observation data'. These data can be used in design element arrangement of interior space, hereafter.

• Korean Institute of Interior Design Journal
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• v.20 no.5
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• pp.96-104
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• 2011

Assuming that different spatial types involves the change of observation time to acquire the spatial information, this study intended to analyze the observation time by interior space types and derive the proper time for spatial evaluation. Coming to the study method, in order to analyze the characteristics of observation time in the image evaluation of interior space by types, it looked into the observation time chosen by the testees during evaluation. The findings of this study are as follows: First, the observation time differed by genders and spatial types: men's average time was longest for modern (93.3 sec.) and natural (89.4 sec.) spaces; women's average time was longest for classic space (110.7 sec.), which was the shortest for men. Second, the intensity of observation time zone differed by spatial types: this finding can imply that different design types require different establishment of observation time for evaluation even if the spatial elements are the same. Third, analyzing the distribution of time zones chosen by most testees showed that men's observation time zones were more intensely distributed than those of women. Fourthly, the observation lime for general space could be derived from the gender-based comparison that excluded the difference by types, but considering that different design types lead to different observation time, it could be seen as proper for evaluation of interior space to establish the difference of observation time by spatial types. Finally, Analysis showed the highest preference to the time '(3)'. However, obtaining information presented is the most highly effective time is '(6). Thus, the preferred time zone is different and effective, according to the results of the analysis.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.2
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• pp.16-24
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• 2010

This paper is proposed a novel fuzzy disturbance observer based on backstepping method for nonlinear systems with unknown disturbance. Using fuzzy logic systems, a fuzzy disturbance observer with the disturbance observation input is introduced for unknown disturbance. To guarantee that the proposed disturbance observer estimates the unknown disturbance, the disturbance observation error dynamic system is employed. Under the framework of the backstepping design, the fuzzy disturbance observer is constructed recursively and an adaptive laws and the disturbance observation input are derived. Numerical examples are given to demonstrate the validity of our proposed disturbance observer for nonlinear systems.

• Corrosion Science and Technology
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• v.22 no.4
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• pp.265-272
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• 2023

The aim of this study was to develop a new in-situ observation method and instrument in micro-scale to investigate the mechanism of stress corrosion cracking (SCC) initiation of Ni-base alloys in a high temperature water environment of pressurized water reactors (PWRs). A laser confocal microscope (LCM), an autoclave with diamond window view port, and a slow strain-rate tester with primary water circulation loop system were components of the instrument. Diamond window, one of the core components of the instrument, was selected based on its optical, chemical, and mechanical properties. LCM was used to observe the specimen in micro-scale, considering the experimental condition of a high-temperature primary water environment. Using in-situ method and instrument, it is possible to observe oxidation and deformation of specimen surface in micro-scale through the diamond window in a high-temperature primary water in real-time. The in-situ method and instrument developed in this work can be utilized to investigate effects of various factors on SCC initiation in a high-temperature water environment.