• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.7C
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• pp.724-729
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• 2009

Binary offset carrier (BOC) signal synchronization is based on the correlation between the received and locally generated BOC signals. Thus, the multiple side-peaks in BOC autocorrelation are one of the main error sources in synchronizing BOC signals. Recently, new correlation functions with no side-peak were proposed for sine and cosine phased BOC signal synchronization, respectively, by the authors [3]. In this paper, we propose a new correlation function with no side-peak for composite BOC (CBOC) signals by using the similar approach to that in the previous work.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.2
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• pp.211-216
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• 2014

Construction of power plants and T&D facilities is so difficult because of the civil complaints and the additional cost according to the concerning field conditions. Therefore, various researches and methods have been considered to get solutions in the demand side and energy storage systems have been in the spotlight because of the various functions such as peak shaving, load shifting, and power system stabilizing, and so on. Residential small size batteries are considered in this paper and the economic analysis is carried out to evaluate the reasonable subsidy levels for the deployment of energy storage systems. Various economic parties are considered to find reasonable subsidy level comparing each other, which parties consist of utilities, participants and non-participants in general. The evaluation is based on California Standard Practice Test and the results are able to be used as subsidy guidelines.

• Wind and Structures
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• v.17 no.2
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• pp.227-244
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• 2013

Non-stationary extreme winds such as thunderstorm downbursts are responsible for many structural damages. This research presents a time domain approach for estimating along-wind load effects on tall buildings using multiple wind speed time history samples, which are simulated from evolutionary power spectra density (EPSD) functions of non-stationary wind fluctuations using the method developed by the authors' earlier research. The influence of transient wind loads on various responses including time-varying mean, root-mean-square value and peak factor is also studied. Furthermore, a simplified model is proposed to describe the non-stationary wind fluctuation as a uniformly modulated process with a modulation function following the time-varying mean. Finally, the probabilistic extreme response and peak factor are quantified based on the up-crossing theory of non-stationary process. As compared to the time domain response analysis using limited samples of wind record, usually one sample, the analysis using multiple samples presented in this study will provide more statistical information of responses. The time domain simulation also facilitates consideration of nonlinearities of structural and wind load characteristics over previous frequency domain analysis.

• Journal of the Korean Society of Radiology
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• v.8 no.7
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• pp.443-447
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• 2014

$^{134}Cs$ radioactive concentration among soil samples is difficult to classify due to the background impact on crust originated natural radioactive nuclide, and overlapping and interfering between peaks. The ways to identify true peaks in gamma-ray spectroscopy are as follows to reduce statistical fluctuation by smoothing based on the fact that the shapes of peak are mostly Gaussian, to inspect the levels of width and height of peaks, to add functions on low-energy trailing phenomena, or 4) to check the peaks after modifying Gaussian function itself. Therefore, it is considered that information and knowledge for spectrum analysis are necessary.

• Nuclear Engineering and Technology
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• v.41 no.1
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• pp.113-124
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• 2009

The line shape functions for the Doppler-broadened gamma ray spectrum are considered in the $^{10}B(n,{\alpha}{\gamma})^7Li$ reaction occurring in a surrounding medium where the excited $^7Li$ nucleus is slowed down and stopped before decay. The phenomenological form of the stopping power was used for the broadening effect. Convolution with the detailed response of a germanium detector is taken into consideration for the simplest case of solely electronic stopping. A numerical study for the analysis of $^{10}B$ by thermal neutron capture is conducted by performing a parametric search and fitting the measured spectrum in a least-squares approach. In comparison with the previous numerical approach using the same analysis, the computational speed is increased and reliable information concerning the stopping power of the medium is obtained while estimating the uncertainty. Implementation of the routine analysis of $^{10}B$ is facilitated on a recent version of the gamma ray spectrum analysis package HyperGam.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5C
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• pp.437-443
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• 2012

In this paper, we propose a novel unambiguous correlation function for binary offset carrier (BOC) signal acquisition. Specifically, we first find out that the side-peaks arise due to the fact that the BOC autocorrelation is the sum of the irregularly shaped BOC sub-correlations, and then, propose an unambiguous correlation function with no side-peak by combining the sub-correlations. The proposed scheme is shown to remove the side-peaks completely for any type of BOC signal and to provide a better acquisition performance than the conventional correlation functions.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.5
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• pp.1050-1056
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• 2009

Heart Rate Variability(HRV) is a parameter that represents monitoring variability of time intervals between R-peak in electrocardiography. HRV serves to various applications, such as indices of autonomic functions, prediction of cardiac sudden death, assessment of stress and emotional, etc. However, as measuring R-peak in ECG needs at least 3-electrodes, and it is inconvenient for end users. In this paper, we suggested the modified laplacian electrodes for measuring HRV at one-point, which are producted by MEMS fabrication and have the two circular electrodes on the pad. For optimal position and direction, we performed an experiment that compared with pearson correlation coefficient and the amplitude of signals, between standard lead II and proposed electrodes. We analyzed the HRV parameters, such as standard deviation of the NN interval(SDNN), high frequency(HF), low frequency(LF), LF/HF ratio. The result showed that the average correlation coefficient and amplitude are 0.967 and 0.685 mVpp at the position 2. The coeffiecient correlation between the standard HRV and proposed electrode-HRV is 0.999

• Journal of Navigation and Port Research
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• v.30 no.5 s.111
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• pp.397-404
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• 2006

Gamcheon harbor was developed as a multipurpose port to mix processing functions of exclusive piers for bulk cargo such as marine products, domestic cargoes. Since the container terminal was opened in 1997, maximum $40,000\sim50,000$ DWT containership have been incoming and outgoing. However, bemuse the breakwater entrance in Gamcheon harbor is narrow and the crossed vessels are ever-present at breakwater front, marine accident danger is high that grasping traffic characteristics is required in reply. Therefore marine traffic characteristics were analyzed for Gamcheon harbor and Gamcheon approaching waters, included the track and traffic volumes of peak hours period in inbound/outbound and front sea area of the harbor in present.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37A no.12
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• pp.1145-1151
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• 2012

In this paper, we propose an unambiguous binary offset carrier (BOC) correlation function with narrow main-peak width for BOC code tracking. Specifically, we first separate a subcarrier pulse into two rectangular pulses, obtain the associated partial correlations, and re-combine the partial correlations to yield the unambiguous correlation function with narrow main-peak width. From numerical results, it is demonstrated that the proposed correlation function provides a significant performance improvement over the conventional correlation functions.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.682-684
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• 2004

The effect of 1/f noise by the random telegraph signal(RTS) on the phase noise and the jitter of CMOS ring Oscillator is investigated. 10 parallel piece-wise-linear current sources connected to each node model the RTS signals. The In, the power spectral density and the jitter of output of the ring oscillator are simulated as functions of the amplitude and time constant of RTS current source. It is confirmed that the increase of amplitude of RTS is directly related to the increase of the width of phase noise md the value of jitter. The shorter the time constant is, the wider width of FET peak and the larger value of cycle to cycle jitter are.