• Mycobiology
• /
• v.38 no.3
• /
• pp.215-218
• /
• 2010

Azoles are currently the most widely used class of antifungal drugs clinically, and are effective for treating fungal infections. Target site of azoles is ergosterol biosynthesis in fungal cell membrane, which is absent in the mammalian host. However, the development of resistance to azole treatments in the fungal pathogen has become a significant challenge. Here, we report the identification and functional characterization of a UPC2 homolog in the human pathogen Cryptococcus neoformans. UPC2 plays roles in ergosterol biosynthesis, which is also affected by the availability of iron in Saccharomyces cerevisiae and Candida albicans. C. neoformans mutants lacking UPC2 were constructed, and a number of phenotypic characteristics, including antifungal susceptibility and iron utilization, were analyzed. No differences were found between the mutant phenotypes and wild type, suggesting that the role of C. neoformans UPC2 homolog may be different from those in S. cerevisiae and C. albicans, and that the gene may have a yet unknown function.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.5
• /
• pp.966-971
• /
• 2010

An adaptive state observer is presented for a class of LTI systems that have a sinusoidal disturbance in the measurement output. Adaptation rules are developed for identifying the unknown sinusoidal disturbance signal from the system output. For the application of the identification result to the state estimation problem, the sinusoidal signal with arbitrary initial phase has been considered in this paper. In order to test the performance of proposed algorithm, comparative computer simulations have been carried out with an existing robust observer. The simulation results show the effectiveness of the proposed method.

• Proceedings of the IEEK Conference
• /
• 2002.07c
• /
• pp.1674-1677
• /
• 2002

In this paper, the new method to extract the features of iris signals is proposed; Multiresolution ICA (M-ICA) provides good properties to represent signals with time-frequency. The conventional methods were to use the technique of filter bank analysis, while ICA is unsupervised learning algorithm using high-order statistics. M-ICA could make use of strengths of learn- ing method and multiresolution. Also, we performed comparative studies of different feature extraction techniques applied to personal identification using iris pat- tern. To measure goodness of methods, we use Fisher’s discriminant ratio to quantify the class-separability of features generated by various techniques.

• The Journal of the Acoustical Society of Korea
• /
• v.21 no.4
• /
• pp.415-420
• /
• 2002

To identify linear parameters of loudspeaker, two methods are presented. Linear parameter identification methods by box method and added mass method are developed. These methods are compared with conventional software to show advantages and disadvantages of developed methods. Results identified by conventional method of Laud software are significantly different from developed methods. But two methods developed show 4% error in Thiele-Small (TS) parameters identified. In box method, it shows that TS parameters are dependent on the amount of porous material.

• Wind and Structures
• /
• v.15 no.4
• /
• pp.285-299
• /
• 2012

This paper describes the development and calibration of a structural monitoring system installed in a 80 meters high steel wind tower supporting a 2.1 MW turbine Wind Class III IEC2a erected in the central part of Portugal. The several signals are measured at four different levels and include accelerations, strains on the tower wall and inside the connection bolts, inclinations and temperature. In order to correlate measurements with the wind velocity and direction and with the turbine operational parameters the corresponding signals are obtained directly from the turbine own monitoring system and are incorporated in the developed system. Results from the system calibration, the structural identification and the initial period of data acquisition are presented in this paper.

• Journal of the Korean Society of Safety
• /
• v.11 no.2
• /
• pp.143-149
• /
• 1996

We propose an Opto-Digital hybrid fingerprint Identification system based on the binary phase extraction joint transform correlator(BPEJTC) for validation and security yerification. It is shown that since the BPEJTC provides higher peak-to-sidelobe ratio than that of the conventional JTC and does not cause correlation peaks due to intra-class association, this system is well-adaptive to the multiple object environments. Experimental results show that this system has a good performance in the presence of multiple images and the variations of the same person.

• Journal of Information Processing Systems
• /
• v.9 no.2
• /
• pp.333-348
• /
• 2013

Mobile authentication/identification has grown into a priority issue nowadays because of its existing outdated mechanisms, such as PINs or passwords. In this paper, we introduce gait recognition by using a mobile accelerometer as not only effective but also as an implicit identification model. Unlike previous works, the gait recognition only performs well with a particular mobile specification (e.g., a fixed sampling rate). Our work focuses on constructing a unique adaptive mechanism that could be independently deployed with the specification of mobile devices. To do this, the impact of the sampling rate on the preprocessing steps, such as noise elimination, data segmentation, and feature extraction, is examined in depth. Moreover, the degrees of agreement between the gait features that were extracted from two different mobiles, including both the Average Error Rate (AER) and Intra-class Correlation Coefficients (ICC), are assessed to evaluate the possibility of constructing a device-independent mechanism. We achieved the classification accuracy approximately $91.33{\pm}0.67%$ for both devices, which showed that it is feasible and reliable to construct adaptive cross-device gait recognition on a mobile phone.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.6
• /
• pp.142-155
• /
• 2000

A MIMO model reference control scheme incorporating the variable structure theory for a vehicle four wheel steering system(4WS) is proposed and evaluated for a class of continuous-time nonlinear dynamics with known or unknown uncertainties. The scheme employs an neural network to identify the plant systems, where the neural network estimates the nonlinear dynamics of the plant. By the Lyapunov direct method, the algorithm is proven to be globally stable, with tracking errors converging to the neighborhood of zero. The merits of this scheme is that the global system stability is guaranteed and it is not necessary to know the exact structure of the system. With the resulting identification model which contains the neural networks, it does not need higher degrees of freedom vehicle model than 3 degree of freedom model. Th proposed scheme is applied to the active four wheel system and shows the validity is used to investigate vehicle handing performances. In simulation of the J-turn maneuver, the reduction of yaw rate overshoot of a typical mid-size car improved by 30% compared to a two wheel steering system(2WS) case, resulting that the proposed scheme gives faster yaw rate response and smaller side angle than the 2WS case.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2004.10a
• /
• pp.211-216
• /
• 2004

In this thesis, we present the Takagi-Sugeno-Kang (TSK) fuzzy model based adaptive controller and adaptive identification for a general class of uncertain nonlinear dynamic systems. We use an estimated model for the unknown plant model and use this model for designing the controller. The hybrid adaptive control combined direct and indirect adaptive control based on TSK fuzzy model is constructed. The direct adaptive law can be showed by ignoring the identification errors and fails to achieve parameter convergence. Thus, we propose an TSK fuzzy model based hybrid adaptive (HA) law combined of the tracking error and the model ins error to adjust the parameters. Using a Lyapunov synthesis approach, the proposed hybrid adaptive control is proved. The hybrid adaptive law (HA) is better than the direct adaptive (DA) method without identifying the model ins error in terms of faster and improved tracking and parameter convergence. In order to show the applicability of the proposed method, it is applied to the inverted pendulum system and the performance is verified by some simulation results.

• International conference on construction engineering and project management
• /
• 2013.01a
• /
• pp.60-65
• /
• 2013

Introducing the concept of construction safety in the design/engineering phase can improve the efficiency and effectiveness of safety management on construction sites. In this sense, further improvements for safety can be made in the design/engineering phase through the development of (1) an automated hazard identification process that is little dependent on user knowledge, (2) an automated construction schedule generation to accommodate varying hazard information over time, and (3) a visual representation of the results that is easy to understand. In this paper, we formulate an automated hazard identification framework for construction safety by extracting hazard information from related regulations to eliminate human interventions, and by utilizing a visualization technique in order to enhance users' understanding on hazard information. First, the hazard information is automatically extracted from textual safety and health regulations (i.e., Occupational Safety Health Administration (OSHA) Standards) by using natural language processing (NLP) techniques without users' interpretations. Next, scheduling and sequencing of the construction activities are automatically generated with regard to the 3D building model. Then, the extracted hazard information is integrated into the geometry data of construction elements in the industry foundation class (IFC) building model using a conformity-checking algorithm within the open source 3D computer graphics software. Preliminary results demonstrate that this approach is advantageous in that it can be used in the design/engineering phases of construction without the manual interpretation of safety experts, facilitating the designers' and engineers' proactive consideration for improving safety management.