• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.629-637
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• 2010

In this study, we analyzed lateral behavior of connected foundation for transmission tower in clay. For this study, we performed model lateral load test, measured load-displacement curve of connected foundation. For the tests, we manufactured connected foundation model that consider a change of rigidity, installed various measuring sensors for understanding of elements and general foundation behavior. From the test results, we measured load capacities using various methods, compared and analyzed these capacities.

• Journal of Power Electronics
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• v.14 no.2
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• pp.383-391
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• 2014

For the digital control of systems such as grid-connected inverters, measuring inverter output currents accurately is essential. However, current measurement offsets are inevitably generated by current measurement paths and cause DC current components in real inverter output currents. Real inverter output currents with DC components cause the DC-link capacitor voltage to oscillate at the frequency of a utility voltage. For these reasons, current measurement offsets deteriorate the overall system performance. A compensation strategy to eliminate the effect of current measurement offsets in grid-connected inverters is proposed in this study. The validity of the proposed compensation strategy is verified through simulations and experiments. Results show that the proposed compensation strategy improves the performance of grid-connected inverters.

• Bulletin of the Korean Mathematical Society
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• v.46 no.5
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• pp.845-856
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• 2009

A block of an orthomodular lattice L is a maximal Boolean subalgebra of L. A site is a subalgebra of an orthomodular lattice L of the form S = A $\cap$ B, where A and B are distinct blocks of L. An orthomodular lattice L is called with finite sites if |A $\cap$ B| < $\infty$ for all distinct blocks A, B of L. We prove that there exists a weakly path-connected orthomodular lattice with finite sites which is not path-connected and if L is an orthomodular lattice such that the height of the join-semilattice [ComL]$\vee$ generated by the commutators of L is finite, then L is pathconnected.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.9
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• pp.863-869
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• 2005

We investigated quench characteristics of superconducting elements connected in series and parallel each other. The serial and parallel connections of superconducting elements causes a difficulty in simultaneous quench due to slight difference between their critical current densities. In other to induce simultaneous quench, we fabricated four type circuits; serially connected circuit before parallel connection, the circuit connected in parallel before serial connection, serially connected circuit before parallel connection with reactors, the circuit connected in Parallel before serial connection with reactors. We confirmed that the simultaneous quenches occurred in serial and parallel connections of superconducting elements using reactors. In addition, the power burden of superconducting elements was smaller than those of serial and parallel connections of superconducting elements without reactors.

• Journal of Families and Better Life
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• v.33 no.1
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• pp.75-85
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• 2015

This study aimed to examine the effects of science activities connected to physical expression on the four-year-old children's creativity. This study conducted an observation of sixty-four children of four years of age attending the kindergartens in the city of Seoul. Thirty-seven were classified in the experimental group and the remaining twenty-seven were in the comparative group. For the statistical analysis of the data collected, the t-test and the analysis of covariance(ANCOVA) were conducted. The findings of this research are as follows. The children of the experimental group who experienced science activities connected to physical expression demonstrated higher score than those of the comparative group in creativity. The result of the research indicates that science activities connected to physical expression, for children, enhances their creativity. Therefore, science activities connected to physical expression can be an effective approach for creativity of young children.

• ETRI Journal
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• v.38 no.2
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• pp.227-234
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• 2016

Herein, we demonstrate clipping distortion suppression of directly modulated multi-IF-over-fiber links using a simple shunt diode predistorter. The dynamic range of a directly modulated analog fiber optic link is limited by nonlinear distortions caused by laser-diode clipping. We investigate the link performance in the context of carrie-to-noise and distortion ratio (CNDR) and error vector magnitude (EVM) requirements when supporting LTE-A services. We also design an analog predistorter with a shunt-diode structure, and demonstrate experimentally that the predistorter has the ability to suppress clipping-induced third-order intermodulation distortions of the link by at most 14 dB. It also improves the CNDR and EVM of the 4-IF-multiplexed LTE-A carriers by 7 dB and 2.9%, respectively.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.258-260
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• 1995

This paper deals with the voltage unbalance of DC link voltage in series connected two 6-step inverters with double chopper preregulator. Each output of the 6-step inverter is connected to each transformer. The secondary windings of one of the transformers is zig-zag connected and the other star connected. The secondary terminals of the two transformers are series connected which makes 12-step output voltage waveform. In this case, the characteristics of the two transformers are rather different each other. The difference results in the voltage unbalance of the two 6-step inverter input capacitor voltages which make the DC link voltage. The degree of the voltage unbalance is analysied with the variations of load power, load power factor and % impedance of the transformer.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.2
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• pp.100-105
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• 2018

In this paper, we determined the driver's stress and fatigue level through physiological signals of a driver in the connected car environment, accordingly designing and implementing the architecture of the connected cars' platforms needed to provide services to make the driving environments comfortable and reduce the driver's fatigue level. It includes a gateway between AVN and ECU for the vehicle control, a framework for native applications and web applications based on AVN, and a sensing device and an emotion estimation engine for application services. This paper will provide the element technologies for the connected car-based convergence services and their implementation methods, and reference models for the service design.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.12 no.4
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• pp.308-318
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• 2012

Captions include information which relates to the images. In order to obtain the information in the captions, text extraction methods from images have been developed. However, most existing methods can be applied to captions with a fixed height or stroke width using fixed pixel-size or block-size operators which are derived from morphological supposition. We propose an edge connected components based method that can extract Korean captions that are composed of various sizes and fonts. We analyze the properties of edge connected components embedding captions and build a decision tree which discriminates edge connected components which include captions from ones which do not. The images for the experiment are collected from broadcast programs such as documentaries and news programs which include captions with various heights and fonts. We evaluate our proposed method by comparing the performance of the latent caption area extraction. The experiment shows that the proposed method can efficiently extract various sizes of Korean captions.

• Speech Sciences
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• v.13 no.2
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• pp.19-33
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• 2006

The purpose of this paper was to examine acoustical characteristics of phonatory offset-onset mechanism in the connected speech of female adults with stuttering and normal nonfluency. The phonatory offset-onset mechanism refers to the laryngeal articulatory gestures. Those gestures are required to mark word boundaries in phonetic contexts of the connected speech. This mechanism included 7 patterns based on the speech spectrogram. This study showed the acoustic features in the connected speech in the production of female adults with stuttering (n=1) and normal nonfluency (n=3). Speech tokens in V_V, V_H, and V_S contexts were selected for the analysis. Speech samples were recorded by Sound Forge, and the spectrographic analysis was conducted using Praat. Results revealed a stuttering (with a type of block) female exhibited more laryngealization gestures in the V_V context. Laryngealization gesture was more characterized by a complete glottal stop or glottal fry both in V_H and in V_S contexts. The results were discussed from theoretical and clinical perspectives.