• Journal of Communications and Networks
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• v.5 no.2
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• pp.167-173
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• 2003

We treat the problem of channel estimation and interference cancellation in multiuser ultra-wide-band (UWB) communication systems over multipath fading channels. The UWB system under consideration employs a random time-hopping impulse radio format. We develop a channel estimation method based on linear weighted algorithm. An iterative channel estimation and interference cancellation scheme is proposed to successively improve the receiver performance. We also consider systems employing multiple transmit and/or receive antennas. For systems with multiple receive antennas, we develop a diversity receiver for the wellseparated antennas. For systems with multiple transmit antennas, we propose to make use of Alamouti’s space-time transmission scheme, and develop the corresponding channel estimation and interference cancellation receiver techniques. Simulation results are provided to demonstrate the performance of various UWB receiver techniques developed in this paper.

• International Journal of Aeronautical and Space Sciences
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• v.12 no.4
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• pp.371-378
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• 2011

In this paper, the wavelet denoising techniques using thresholding method are applied to the low cost micro electromechanical system (MEMS)-global positioning system(GPS) integrated system. This was done to improve the navigation performance. The low cost MEMS signals can be distorted with conventional pre-filtering method such as low-pass filtering method. However, wavelet denoising techniques using thresholding method do not distort the rapidly-changing signals. They can reduce the signal noise. This paper verified the improvement of the navigation performance compared to the conventional pre-filtering by simulation and experiment.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.7
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• pp.352-360
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• 2003

This paper deals with a simple method in order to analyze and compare the harmonic characteristics in the multi-level inverter. Generally, the magnitude of harmonic components becomes different according to the multi-carrier Pulse Width Modulation(PWM) techniques, the modulation index($M_i$) and the switching frequency The previous papers analyzed the harmonic characteristics from the viewpoint of the space voltage vector. Hence, the calculation of the harmonic vector becomes more difficult and complex in 4-level or over 5-level. However, the proposed method has reduced an amount of calculation and simplified the process of it, using the relationship between the reference voltage and the output phase voltage to the load neutral point. It is applied to the 5-level cascade inverter and the harmonic characteristics for each multi-carrier PWM technique are compared through the simulation.

• Nuclear Engineering and Technology
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• v.37 no.2
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• pp.127-138
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• 2005

Approaches to several recent issues in the operation of nuclear power plants using computational intelligence are discussed. These issues include 1) noise analysis techniques, 2) on-line monitoring and sensor validation, 3) regularization of ill-posed surveillance and diagnostic measurements, 4) transient identification, 5) artificial intelligence-based core monitoring and diagnostic system, 6) continuous efficiency improvement of nuclear power plants, and 7) autonomous anticipatory control and intelligent-agents. Several changes to the focus of Computational Intelligence in Nuclear Engineering have occurred in the past few years. With earlier activities focusing on the development of condition monitoring and diagnostic techniques for current nuclear power plants, recent activities have focused on the implementation of those methods and the development of methods for next generation plants and space reactors. These advanced techniques are expected to become increasingly important as current generation nuclear power plants have their licenses extended to 60 years and next generation reactors are being designed to operate for extended fuel cycles (up to 25 years), with less operator oversight, and especially for nuclear plants operating in severe environments such as space or ice-bound locations.

• Journal of Power Electronics
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• v.17 no.5
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• pp.1244-1255
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• 2017

The space vector pulse width modulation (SVPWM) technique is a popular PWM method for medium voltage drive applications. Conventional SVPWM (CSVPWM) and bus clamped SVPWM (BCSVPWM) are the most common SVPWM techniques. This paper evaluates the performance of various advanced BCSVPWM strategies in terms of their harmonic distortion and switching loss based on a uniform frame work. A uniform frame work, pulse number captures the performance parameter variations of different SVPWM strategies for various number of samples with heterogeneous pulse numbers. This work compares different advanced BCSVPWM techniques based on the modulation index and location of the clamping position (zero vector changing angle ) of a phase in a line cycle. The frame work provides a fixed fundamental frequency of 50Hz. The different BCSVPWM switching strategies are implemented and compared experimentally on a 415V, 2.2kW, 50Hz, 3-phase induction motor drive which is fed from an IGBT based 2 KVA voltage source inverter (VSI) with a DC bus voltage of 400 V. A low cost PIC microcontroller (PIC18F452) is used as the controller platform.

• Journal of Electrical Engineering and Technology
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• v.12 no.2
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• pp.911-917
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• 2017

There are generally three folds when developing neural network classifiers. They are as follows: 1) discriminant function; 2) lots of parameters in the design of classifier; and 3) high dimensional training data. Along with this viewpoint, we propose space search optimized polynomial neural network classifier (PNNC) with the aid of data preprocessing technique and simultaneous tuning strategy, which is a balance optimization strategy used in the design of PNNC when running space search optimization. Unlike the conventional probabilistic neural network classifier, the proposed neural network classifier adopts two type of polynomials for developing discriminant functions. The overall optimization of PNNC is realized with the aid of so-called structure optimization and parameter optimization with the use of simultaneous tuning strategy. Space search optimization algorithm is considered as a optimize vehicle to help the implement both structure and parameter optimization in the construction of PNNC. Furthermore, principal component analysis and linear discriminate analysis are selected as the data preprocessing techniques for PNNC. Experimental results show that the proposed neural network classifier obtains better performance in comparison with some other well-known classifiers in terms of accuracy classification rate.

• Korean Institute of Interior Design Journal
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• v.20 no.1
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• pp.80-88
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• 2011

Designs of Takashi Sugimoto suggested new concepts on the space after broking out fixed ideas, and attempted spatial expressions differently from existing interior decorations through independent thoughts and new interpretations. It is showing orientalism's influences strongly based on Japanese traditional beauty unlike western country's design trends. Takashi Sugimoto is implementing unique own design viewpoints by using materials in nature rather than artificial ones, and stressing extra ordinary view of the world having been edited with daily life through traditions and local cultures along with recycling old daily goods and wastes rather than pursuing modem and futuristic spatiality. Sugimoto thought that beautiful designs and uncommon ideas could be gotten from simple daily experiences, and thus materialized it with a technique of extraordinary daily life's implementation through such design viewpoints. Also, He pursues designs in which dense communications are made variously between spaces, space and user, and this becomes design techniques having been used mostly in his projects. It creates soft boundaries through using certain objet as an intermediate of doing communication or erasing physical boundaries, and then induces close communication within the space. This design viewpoints and techniques of Takashi Sugimoto have directed own discriminated designs nowadays.

• Korean Institute of Interior Design Journal
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• v.20 no.5
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• pp.68-77
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• 2011

In this research it is concentrated first of all on the attempts to reconstruct the historical context of the idea for the space design based on the natural construction and to re-appropriate il critically to the present context. Sequentially in the areas of philosophy, biology, neuroscience, and architecture it has been variously discussed on the problems about the synthesis of biology and techniques. In the context of the consilience of biology and technique Werner Nachtigall, who has intended to shed light on the morphological principles in the natural construction, founded the 'Bionik', which is different from the bionics or the biomechanics that are oriented to the imitation of natural forms. The space design that is on the basis of the Bionik treats organisms as a functional whole. Therefore the Bionik space design follows two kinds of principle such as the principle of analogy and the principle of optimization. After all the understanding of the consilience of nature and technique for Nachtigall and Bionik designers tends toward the explication of the complex process in which the human perceptions, the environment, and the phenomenal techniques are united together, and this complex process is associated with the space design based on the Bionik.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.4
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• pp.113-121
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• 2020

The Chinese Architect Wangshu, who won the Pritzker Architecture Prize at 2012, is the first and only winner in China. This study focused on the expression of his unique architectural ideas. Especially with a high interest in Chinese traditional calligraphy and landscape painting, Wangshu tried to use its traditional features to form his own architectural way. First this study looked at the features of calligraphy and landscape painting. Second this research studied the expression of Wangshu's architectural practice in calligraphy's way. Lastly this study furthered study of Wangshu's architecture combined with landscape paintings' features. The results state these following. 1) For calligraphy, he used the "modular composition" of Chinese characters to architectural composition, which included architectural form and materials. The "similarities" and "space creation" of calligraphy are respectively applied to architectural spatial details and site planning. 2) For landscape painting, Wangshu borrows its elements to compose his architecture with "gardening consciousness". The "view method" of paintings was used to his architectural pedestrian flows, and Wangshu also based on the "space creation" of landscape painting to do architectural space design with creating the similar atmosphere.

• Journal of the Korean housing association
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• v.20 no.1
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• pp.45-58
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• 2009

This research starts from the questioning of current housing development on the hilly site in Korea. It aims to investigate various design techniques of low-rise housing as an alternative housing plan on hilly sites. Several generic solutions of the combination of building type and road pattern are tested for a simulation process, and evaluated in terms of crucial design issues; development density, parking space and open space. As a result, four reasonable models are selected for making full use of geographical features of hilly site, two models each land slope of $18^{\circ}$ and $26^{\circ}$. Several design techniques for each model are also suggested, in ensuring the development feasibility by considering land slope, vehicular access and parking, common open space, and community facilities.