• Journal of Advanced Navigation Technology
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• v.13 no.6
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• pp.943-949
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• 2009

In this paper, the 5.9GHz WAVE(Wireless Access in Vehicular Environments) channel modeling is used by the Jakes channel model for the suitability of the fast wireless channel fluctuation. The performance analysed the fading signal constellation and the spectrum in the IEEE 802.11p spectrum mask, the Doppler effect, the modulation scheme. In addition, the vehicular speed, exactly the performance analysis the WAVE communication systems follow the Doppler effect.

• Journal of the Korean Society of Food Culture
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• v.33 no.6
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• pp.501-511
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• 2018

Studies with various approaches are required for the globalization of Korean Food. The objectives of this study were i) how the preferences of foreign students residing in Korea on K-Wave, K-Drama, K-Pop and K-Friend affect their preference, satisfaction level and repurchase intention on Korean food, and ii) which of the factors have the strongest effects on their preference, satisfaction level and repurchase intention on Korean food. The results showed that the higher K-Wave, K-Drama, K-Pop and K-Friend preferences, the stronger effect on the preference, satisfaction level and repurchase intention on Korean food (p=0.0001). Among the factors for Korean food preference, the most critical one was K-Wave preference (p=0.0001), followed by K-Drama preference (p=0.0500). For the satisfaction level of Korean food, the most important factor among the four was K-Wave preference (p=0.0496), followed by K-Drama preference (p=0.0500). For the repurchase intention on Korean food, the most significant factor was the preference for K-Friend (p=0.0004), followed by K-Drama (p=0.0016) and K-Wave (p=0.0030). Based on these results, more efforts to invigorate the preferences for K-Wave and K-Drama, as well as various attempts to improve the preference for K-Friend are required for the globalization of Korean Food.

• Journal of Advanced Navigation Technology
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• v.13 no.6
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• pp.933-942
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• 2009

In this paper, the WAVE technology for IT based on Intelligent Transport System(ITS) which using by IEEE 802.11a PHY, IEEE 802.11p MAC(Medium Access Control) and IEEE P1609.3 was implemented. The WAVE system was designed that has maximum 0.5km communication range for RSU(Road Side Equipment) between vehicle, 12Mbps transfer speed when downlink at maximum 120km/h vehicle speed. To verify suitableness of the WAVE system for ITS, we measured several parameters on the real road: communication range when low and high speed, link establishment time, data transfer speed, PER (Percent Error Rate), and latency. From the experiment results, we demonstrated that WAVE is a suitable technology for IT based on ITS.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.05
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• pp.186-189
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• 1995

This paper performed P wave detection algorithm for diagnosis in according to method of cardiologist's P wave detection. We used correlation pattern matching for prominent P waves and P-P interval estimation for ambiguous P waves. Results of this study indicate that this algorithm has potential for improving P wave detection performance.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.5
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• pp.18-23
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• 2010

In this paper, we propose a computationally efficient method detecting the P300 wave for brain-machine interface. Electrophysiological researches have shown that the P300 wave's potential is decreased when human intention matches visual stimulation. Motivated by this fact, we can infer human intention for brain-machine interface by detecting the P300 wave's potential decrease. The P300 wave is recorded from EEG(electroencephalogram) electrodes attached on human brain skull after giving alphabetical stimulation. To detect the potential decrease in P300, firstly we statistically model the P300 wave's negative potential. Then we infer human intention based on maximum likelihood estimation. The proposed method was evaluated on the data recorded from three healthy human subjects. The method achieved an averaging accuracy of 98% from subject k, 90% from subject j and 79.8% from subject h.

• Journal of the Korean Geophysical Society
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• v.8 no.2
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• pp.67-74
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• 2005

Two-dimensional S-wave velocity sections from SH-wave refraction tomography and surface wave dispersions were obtained by inverting traveltimes of first arrivals and surface wave dispersions, respectively. For the purpose of comparison, a P-wave velocity tomogram was also obtained from a P-wave refraction profiling. P and Rayleigh waves generated by vertical blows on a plate with a sledgehammer were received by 100- and 4.5-Hz geophones, respectively. SH-waves generated by horizontal blows on both sides of a 50 kg timber were received by 8 Hz horizontal geophones. The shear-wave signals were enhanced subtracting data of left-side blows from ones of the right-side blows. Shear-wave velocities from tomography inversion of first-arrival times were compared with ones from inverting dispersion curves of Rayleigh waves. Although the two velocity sections look similar to each other in general, the one from the surface waves tends to have lower velocities. First arrival picking of SH waves is troublesome since P and PS-converted waves arrive earlier than SH waves. Application of the surface wave method, on the other hand, is limited where lateral variation of subsurface tructures is not mild.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.41-47
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• 1989

Using computer simulated irregular waves, variations of ocean wave statistics according to sea state are analyzed, and the reasonable conditions that transform the energy spectrum to individual wave statistics are discussed. Ocean wave statistics varying with sea state are found to respond linearly to the spectral peakedness parameter $Q_p$ and spectrum moments $m_n$ (n = 0, 1, 2${\cdots}{\cdots}\;\infty$ ). It is clarified that the 2nd-order spectrum moment is a reasonable parameter which represents the wave statistics including wave periods, and that the spectrum analysis should be carried out under the conditions of minimum data length of 10 times of peak period $T_p$ with time lag of $7T_p$ to satisfy the stable condition of wave statistics.

• International Journal of Railway
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• v.1 no.2
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• pp.64-71
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• 2008

The quality of track-bed fills of railways has been controlled by field measurements of density $({\gamma}_d)$ and the results of plate-load tests. The control measures are compatible with the design procedures whose design parameter is $k_{30}$ for both ordinary-speed railways and high-speed railways. However, one of fatal flaws of the design procedures that there are no simple laboratory measurement procedures for the design parameters ($k_{30}$ or, $E_{v2}$ and $E_{v2}/E_{v1}$) in design stage. A new quality control procedure, in parallel with the advent of the new design procedure, is being proposed. This procedure is based upon P-wave velocity involving consistently the evaluation of design parameters in design stage and the field measurements during construction. The Key concept of the procedure is that the target value for field compaction control is the P-wave velocity determined at OMC using modified compaction test, and direct-arrival method is used for the field measurements during construction. The procedure was verified at a test site and the p-wave velocity turned out to be an excellent control measure. The specifications for the control also include field compaction water content of OMC${\pm}$2% as well as the p-wave velocity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.2206-2211
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• 2012

To identify the effect of the aroma foot spa on the stress, 12 university students with stress were divided into control group (6 subjects) and aroma foot spa group (6 subjects). Control group was not subjected to any kind of intervention while aroma foot spa group was subjected to 10 minutes of foot bath using 5% Juniper, lavender and lemon essential oil and 10 minutes of foot massage using massage cream during four weeks, two times per week. As for the evaluation method, brain wave was studied to measure the amount of change in stress. After measuring the change in the brain wave before and after the experiment, it was proven that the aroma foot spa group s Alpha wave (Z=-2.364, p<.05) and SMR wave (Z=-1.981, p<.05) were higher than those of the control group. Moreover, when the pre and post experiment results of the aroma foot spa group were measured, it was proven that the Theta wave (Z=-2.366, p<.05) decreased while Alpha wave (Z=-2.371, p<.05) increased. In other words, aroma foot spa that included foot bath using essential oil and foot massage increased Alpha wave which in turn influenced the brain wave due to increased blood circulation resulting from muscle relaxation. Moreover, SMR wave increase was closely related to the change in Alpha wave, which demonstrates that SMR wave increased due to stress alleviation. Accordingly, it may be possible to assume that aroma foot spa is effective in relieving stress.

• Geomechanics and Engineering
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• v.14 no.4
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• pp.399-406
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• 2018

The influences of mineral content and porosity on ultrasonic wave velocity were assessed for ten hornfelsic rocks collected from southern and western parts of the city of Hamedan, western Iran. Selected rock samples were subjected to mineralogical, physical, and index laboratory tests. The tested rocks contain quartz, feldspar, biotite, muscovite, garnet, sillimanite, kyanite, staurolite, graphite and other fine grained cryptocrystalline matrix materials. The values of dry unit weight of the rocks were high, but the values of porosity and water absorption were low. In the rocks, the values of dry unit weight are related to the presence of dense minerals such as garnet so not affected by porosity. The statistical relationships between mineral content, porosity and ultrasonic wave velocity indicated that the porosity is the most important factor influencing ultrasonic wave velocity of the studied rocks. The values of P-wave velocity of the rocks range from moderate to very high. Empirical equations, relevant to different parameters of the rocks, were proposed to determine the rocks' essential characteristics such as primary and secondary wave velocities. Quality indexes (IQ) of the studied samples were determined based on P-wave velocities of them and their composing minerals and the samples were classified as non-fissured to moderately fissured rocks. Also, all tested samples are classified as slightly fissured rocks according to the ratio of S-wave to P-wave velocities.