• Journal of Fashion Business
• /
• v.15 no.1
• /
• pp.92-102
• /
• 2011

The purpose of this research is to study the types of name spectrum and their characteristics of domestic men's wear brands focusing on formal and casual wear and also examine the differences based on the type of brands' product and brand style. Total 184 of men's wear brands, which were consisted of 66 formal wear brands and 84 casual wear brands, were selected from '2009 Korea Fashion Yearbook'. For data analysis, quantitatively evaluated the frequency and qualitatively evaluated the image of brand product and the meaning of brand name. The result as follows; 1. The domestic fashion brands for men's wear appeared to have four types of name spectrum. The descriptive name was the most frequently showed, and followed by arbitrary, suggestive, and coined name. For formal wear brands, four types of name spectrum were appeared in the order of descriptive, suggestive, coined, and arbitrary name. In casual wear brands, three types of name spectrum were appeared in the order of descriptive, arbitrary, and suggestive name. 2. The characteristics of men's brand name according to their name spectrum was as follows.; In the descriptive brand names, person's name was used the most and some ascribed the characteristics, feature or geographic location of the product. The suggestive brand names contained images and symbols of the product and also implied the relevant benefit information in a particular product context. In the arbitrary brand name, they imply the various meanings according to the product and are made up of either coined or natural. For the coined name, some bear the ideology or symbolized the characteristics of product itself. 3. The descriptive name spectrum showed the most in domestic menswear brands, regardless of the brand type. Except this, there were differences in the type and the frequency of name spectrum depending on the brand type.

• Applied Chemistry for Engineering
• /
• v.19 no.2
• /
• pp.151-156
• /
• 2008

The annals of Joseon Dynasty is the most valuable resource containing the record of Korean history and has been known as one of the UNESCO's Memory of the World Register. There was a period that the annals of Joseon Dynasty was used with beeswax to control pests. It is considered as the prior reason of damage on the annals of Joseon Dynasty. Therefore, in this study we analysed the spectrum of traditional paper inside and outside of Korea, beeswax and accelerated artificial aging paper to restore the waxed volume in the annals of Joseon Dynasty by using FT-IR. As a result of FT-IR analysis, spectrum did not showed its big difference in all paper used in this study. However, there was a different spectrum in paper which was made with not Broussonetia kazinoki, but Echinochloa crus-galli var. frumentacea and Dioscorea batatas. Among traditional papers in various countries, spectrum of Korean paper showed the most similarity from the annals of Joseon Dynasty. In comparison between accelerated artificial aging paper and waxed volume, we could identify the change of spectrum affected by the damage.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.20 no.3
• /
• pp.257-263
• /
• 2009

Recently, as the 3G services of Korea have stepped into the developing stage and the traffic has been rapidly increasing, the spectrum requirements have been getting very large. Therefore spectrum reforming is considered actively and firstly exact methodology of spectrum requirement estimation is needed. But existing methodology depends on the future's service forecast than the present substantial data. This paper proposed the exact methodology of spectrum requirement estimation is based on the real data. So this paper analyzed the characteristics of Korean mobile communication traffic based on the real data and the algorithm suitable for estimation of spectrum requirements for 3G mobile communications, and calculated the parameters needed to estimate the spectrum requirements. Based on the traffic parameters of December 2007, simulations to Bet the estimation of annual spectrum requirements were implemented for the two different cases: one of which is 44 % annual increase in the data traffic and the other is 21 % annual increase. The simulation results show 90 MHz for the first case and 60 MHz for the second case in December 2011.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.7 no.8
• /
• pp.1629-1637
• /
• 2003

In this paper, we analyzed the performance of a hybird DS/SFH(Direct­Sequency­Slow Frequency­Hopping) Spread Spectrum system with BFSK modulation over Nakagami­m fading channel with multitone jamming. The performance of the system was improved when a frequency bowing rate increased. In case that process gain of hybrid DS/SFH Spread Spectrum system to be fixed, the hybrid DS/SFH Spread Spectrum takes the low bit error probability than a DS Spread Spectrum system. Also, when the fading index m increases, the fading effect decrease, when the JSR(jamming to signal power ratio) increases ,the performance of a hybrid DS/SFH Spread Spectrum system improved than DS Spread Spectrum system. The result, we have been proved that performance of a hybrid DS/SFH Spread Spectrum was superior to DS Spend Spectrum system over Nakagami­m fading with tome jamming.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.4
• /
• pp.1392-1413
• /
• 2022

In order to meet the rapid development of the unmanned aerial vehicle (UAV) communication needs, cooperative spectrum sensing (CSS) helps to identify unused spectrum for the primary users (PU). However, multi-UAV mode (MUM) requires the large communication resource in a cognitive UAV network, resulting in a severe decline of spectrum efficiency (SE) and energy efficiency (EE) and increase of energy consumption (EC). On this account, we extend the traditional 2D spectrum space to 3D spectrum space for the UAV network scenario and enable UAVs to proceed with spectrum sensing behaviors in this paper, and propose a novel multi-slot mode (MSM), in which the sensing slot is divided into multiple mini-slots within a UAV. Then, the CSS process is developed into a composite hypothesis testing problem. Furthermore, to improve SE and EE and reduce EC, we use the sequential detection to make a global decision about the PU channel status. Based on this, we also consider a truncation scenario of the sequential detection under the sensing delay constraint, and further derive a closed-form performance expression, in terms of the CSS performance and cooperative efficiency. At last, the simulation results verify that the performance and cooperative efficiency of MSM outperforms that of the traditional MUM in a low EC.

• Journal of Biomedical Engineering Research
• /
• v.18 no.3
• /
• pp.273-283
• /
• 1997

Electrogastrography(EGG), the cutaneous recording of the myoelectrical activity of the stomach using surface electrodes, is attactive due to its non-invasiveness. Despite many attempts made over the decades, analysis of surface EGG has not led to identification of contraction-related electrical response activity of the stomach that would help the clinician to diagnose motility disorders of the stomach. We propose feasible methods to detect the gastric contraction by spectrum analysis and vector analysis of the surface EGG signal. A running spectral analysis(RSA) based on the fast Fourier transform (FFT) was applied to the filtered EGG signal. The powers of dominant frequency and its harmonics were compared with gastric contraction signals such as the strain gauge signal from the gastric serosa in dog or the antropyloric pressure in human. And we also carried out vector analysis of the filtered EGG signals obtained from three paired electrodes. The amplitude and direction of the calculated EGG vector were analyzed and compared with the gastric contraction signals. From the spectrum analysis, we found that the increase of the power of the first harmonic of the dominant frequency was highly correlated with the gastric contraction. And from the vector analysis of the EGG signal, we found a typical change of the amplitude and direction of the EGG vector, which can indicate occurrences of the gastric contraction.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.47 no.4
• /
• pp.112-118
• /
• 2010

This paper describes a noise suppression system based on a normalization method using a time-delay neural network and line spectrum pair having a parameter of frequency domain. First, a time-delay neural network is trained using line spectrum pair values of noisy speech signals obtained by linear prediction analysis. After trained the time-delay neural network, the proposed system enhances speech signals that are degraded by a background noise. Accordingly, the proposed time-delay neural network restores from the line spectrum pair values of noisy speech signals to the line spectrum pair values of clean speech signals. It is confirmed that this system is effective for speech signals degraded by a background noise, judging from spectral distortion measurement.

• Journal of Advanced Navigation Technology
• /
• v.7 no.2
• /
• pp.118-127
• /
• 2003

ITU-R recommends general methodology to provide current and future mobile communication services and 12 parameters to calculate terrestrial spectrum requirements. In this paper we analyzed 12 parameters suggested by ITU-R Recommendation and provided a method to determine a specific parameter value in a specific region. We calculated spectrum requirements and network resources for year 2010 in Korean mobile environment by applying parameter values acquired in parameter analysis method of this paper. And we analyzed the variation of spectrum requirements by calculating spectrum requirements depending on variation of parameters for future mobile communication services.

• Journal of information and communication convergence engineering
• /
• v.13 no.4
• /
• pp.241-247
• /
• 2015

Cognitive radio has been attracting increased attention as an effective approach to improving spectrum efficiency. One component of cognitive radio, spectrum sensing, has an important relationship with the performance of cognitive radio. In this paper, after a summary and analysis of the existing spectrum-sensing algorithms, we report that the existing eigenvalue-based semi-blind detection algorithm and blind detection algorithm have not made full use of the eigenvalues of the received signals. Applying multi-antenna systems to cognitive users, we design a variety of spectrum-sensing algorithms based on the joint distribution of the eigenvalues of the received signal. Simulation results validate that the proposed algorithms in this paper are able to detect whether the signal of the primary user exists or not with high probability of detection in an environment with a low signal-to-noise ratio. Compared with traditional algorithms, the new algorithms have the advantages of high detection performance and strong robustness

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.05a
• /
• pp.474-477
• /
• 2013

As the market-based spectrum policy is introduced, an interest in the economic value of the frequency is increasing. Research and practical applications concerning the methodology for the estimation of the economic value of the frequency and its determinants are actively engaged, which are used for setting a reserve price and bid price of spectrum auction and a spectrum clearance cost. In this study, by the analysis of the spectrum valuation methodology, we derive the changes in the factors affecting the valuation and propose to apply improved. In the model frequency value is consist of technical value, commercial value and strategic value, we find the dynamics of fluctuation factors and suggest how to apply them to spectrum policy.