• Korean Journal of Remote Sensing
• /
• v.1 no.1
• /
• pp.63-87
• /
• 1985

Considerable experience has been reported on the use of spectral data to measure the canopy biomass of dryland grain crops and the use of these estimates to forecast subsequent grain yield. These basic procedures were retested to assess the use of the general process to forecasting grain yield for paddy rice. The use of the ratio of a multiband radiometer simulation of Thematic Mapper band 4(.76 to .90 .mu.m) divided by band 3 (.63 to .69 .mu.m) was tested to estimate the canopy biomass of paddy rice as a function of the stage of development of the rice. The correlation was found to be greatest (R = .94) at panicle differentiation about midway through the development cycle of the rice canopy. The use of this ratio of two spectral bands as a surrogate for canopy biomass was then tested for its correlation against final grain yield. These spectral estimates of canopy biomass produced the highest correlations with final grain yield (R = .87) when measured at the canopy development stages of panicle differentiation and heading. The impact of varying the amounts of supplemental nitrogen on the use of spectral measuremants of canopy biomass to estimate grain yield was also determined. The effect of the development of a significant amount of weed biomass in the rice canopy was also clearly detected.

• Journal of information and communication convergence engineering
• /
• v.1 no.1
• /
• pp.1-5
• /
• 2003

This paper discusses the spectral efficiency and performance of asynchronous direct sequency spread spectrum multiple access systems strict bandwidth limitation by Nyquist filtering. The signal to noise plus interference ratio(SNIR) at the output from the correlation receiver is derived analytically taking the cross correlation characteristics of spreading sequences into account, and also an approximated SNIR of a simple form is presented for the systems employing Gold sequences. Based on the analyzed result of SNIR, bit error rate performance and spectral efficiency are also estimated. and at last, we analyzed improvement rate using RS, convolution as a method for improving functions.

• The Korean Journal of Physiology and Pharmacology
• /
• v.3 no.5
• /
• pp.491-499
• /
• 1999

This study was designed to evaluate the efficacy of dynamic parameters, such as correlation dimension $D_2,$ by comparing spectral electroencephalographic (EEG) parameters. These parameters are used to estimate the depth of halothane anesthesia as defined by the presence of body movement in response to a tail clamp. Six rats were used and each of them was exposed to halothane sequentially at the concentrations of 0%, 0.5%, 1.0% and 1.5% for 30 min. A tail clamp was applied every five min and the movements were recorded at each concentration level. The spectral parameters and the dynamic parameters were derived from 20-sec and 10-sec segments, respectively, from the last 5-mins of EEG recording at each concentration level. Correlation coefficients between the parameters and the movements were calculated. Standardized values of three parameters, betaL power, median power frequency (MPF), and $D_2$ were derived by calculation based on the number of animals showing the movement in response to a tail clamp. The betaL power had the largest correlation coefficient to spontaneous movement and to the response to a tail clamp than any other band parameter. MPF had a better correlation with the movement than 90% spectral edge frequency. Among the dynamic parameters, $D_2$ on the parietal cortex had a better correlation with the movement. The level of deviation and variation of standardized $D_2,$ MPF, and betaL were significant (p<0.01). The order of deviation and variation was; betaL power > MPF > $D_2.$ The correlation dimension serves as a better index for the depth of halothane anesthesia defined in forms of a response to external stimulation.

• Journal of Advanced Navigation Technology
• /
• v.17 no.3
• /
• pp.298-305
• /
• 2013

In this paper, we propose simple combining schemes for sensing ATSC digital television signals with spectral correlation density (SCD). The detection algorithms exploiting the cyclostationarity exhibited by the pilot of ATSC digital television signals usually use the SCD value at a given particular frequency. However, we found that non-zero SCDs are found to be distributed over a certain range of frequencies in multipath fading environment. To utilize a set of non-zero SCD values computed in the vicinity of the pilot location, we formulate a class of combining methods in analogy with the maximal ratio combining, the square law combining and the equal gain combining. We show that the proposed simple combining schemes improve the detection performance by 0.5~1.0dB under multipath fading environments.

• Journal of Institute of Control, Robotics and Systems
• /
• v.19 no.9
• /
• pp.853-859
• /
• 2013

The purpose of this study was to identify the correlation between electroencephalography (EEG) and strength, using grip strength. 64-channel EEG data were recorded from five healthy subjects in tasks requiring handgrip contractions of nine levels of MVC (Maximal Voluntary Contraction). We found the ERS (Event-Related Synchronization)/ERD (Event-Related Desynchronization) at the measured EEG data using STFT (Short-Time Furier Transform) and spectral power in the EEG of each frequency range displayed in the graph. In this paper, we identified that the stronger we contracted, the greater the spectral power was increased in the ${\beta}$, ${\gamma}$ wave.

• Proceedings of the KSRS Conference
• /
• 2008.10a
• /
• pp.111-114
• /
• 2008

The existence of noise bands may deform the typical shape of the spectrum, making the accuracy of clustering degraded. This paper proposes a statistical approach to remove noise bands in hyperspectral data using the correlation coefficient of bands as an indicator. Considering each band as a random variable, two adjacent signal bands in hyperspectral data are highly correlative. On the contrary, existence of a noise band will produce a low correlation. For clustering, the unsupervised ${\kappa}$-nearest neighbor clustering method is implemented in accordance with three well-accepted spectral matching measures, namely ED, SAM and SID. Furthermore, this paper proposes a hierarchical scheme of combining those measures. Finally, a separability assessment based on the between-class and the within-class scatter matrices is followed to evaluate the applicability of the proposed noise band removal method. Also, the paper brings out a comparison for spectral matching measures.

• Publications of The Korean Astronomical Society
• /
• v.30 no.2
• /
• pp.531-533
• /
• 2015

We have investigated the long term variability of the intensities of the broad-line region emission lines in the UV spectra of Seyfert I galaxy NGC 5548 from 1973-1996. We have obtained the following results: 1) a high level correlation between the intensities of emission lines as well as between intensities of emission lines and continuum fluxes was discovered. With increasing wavelength the correlation in both cases becomes weaker, 2) the relationship between the intensity of emission lines and the flux radiation in the continuum can be expressed by a power law function with coefficients of ${\alpha}{\approx}0.8-1.1$ for different lines. When the difference between the wavelengths of spectral lines and the continuum is increased, the value of the power function decreases, and 3) it was found that the magnitude of the variability of the line intensities are weaker than the range of variability of the continuum fluxes. The magnitude of the variability of the line intensities and the continuum fluxes increase at longer wavelengths.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.20 no.10
• /
• pp.940-945
• /
• 2010

Noise reduction of vacuum cleaner is important, according as get into standard that estimate quality of product. To reduce noise of vacuum cleaner, we need analysis of correct noise source and contribution grasping about Identified noise sources' output noise. Because noise sources' correlation exists in vacuum cleaner that is small and complicated system, analysis is not easy. In this case, we need to apply Multi-dimensional spectral analysis(MDSA) method that can remove correlation between noise sources and grasp pure contribution degree of noise sources. In this study, we take transfer path analysis between output noise and noise that measured in inside/outside of vacuum cleaner.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1993.10a
• /
• pp.334-343
• /
• 1993

In order to evaluate the quality of peaches non-destructively, the surface color and spectral reflectance of KURAKATAWASE, MIBAEKTO and OKUBO cultivar were measured. Also an attempt was made to correlate reflectance characteristics with quality evaluation parameters such as chlorophyll, anthocyanin , soluble solid , and firmness.

• Journal of Biosystems Engineering
• /
• v.19 no.1
• /
• pp.33-41
• /
• 1994

In order to evaluate the quality of peaches non-destructively, the surface color and spectral reflectances of KURAKATAWASE, MIBAEKTO, and OKUBO cultivar were measured. Also an attempt was made to correlate reflectance characteristics and tristimulus values with quality evaluation parameters such as chlorophyll content, soluble solids, anthocyanin content, and firmness. Further analysis of the correlation coefficients showed that spectral reflectance would be effective for the quality evaluation of peaches.