• Phonetics and Speech Sciences
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• v.2 no.4
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• pp.11-18
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• 2010

This study compared classical operatic singing and applied music singing using the vocal assessment software, Dr. Speech and SPEAD from Lx Speech Studio. Participants in this study included: eight female operatic singers (mean 22.6 yrs, average career 7.5 yrs); eight male operatic singers (mean 25.6 yrs, average career 7.3 yrs); eight female applied music singers (mean 25.1 yrs, average career 6.1 yrs); and eight male applied music singers (mean 27.6 yrs, average career 6.8 yrs). The results demonstrated significantly higher closed quotient values in female applied music singers during singing (p<.05). In addition, higher closed quotient values in speaking were presented in male classical singers and longer MPT was obtained in female operatic singers (p<.05). Furthermore, singer's formants were identified in all male operatic singers and in three female operatic singers. In contrast, only one applied music male and one female singer showed singer's formants while singing.

• Journal of Environmental Science International
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• v.7 no.2
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• pp.157-164
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• 1998

preliminary study on the chemical compositions of forty seven precipitations from March 1994 to May 1995 In Yeoncheon-gun, which Is adjacent to the southern boundary of demilitarized zone (DMZ) in the northernmost tip of Kyunggi Province has been Performed. The metal cation and anion concentrations were measured by atomic absorption spectrometer and ion chromatography, respectively. pH/lon meter and direct nesslerization method were used for the concentration measurements of $H^+$ ion and $NH_46+$ ions, respectively Based on the data, the quantitative orders of the cation and anion average concentrations were $Ca^{2+}>NH_4^+>Na^+>K^+>Mg^{2+}>H^+ and SO_4^{2+}>Cl^-> NO_3^-$, respectively..The ratio of average total anion concentration to average total cation concentration was 0.97. The average pH value of the precipitations was 5.60. These results, correlation coefficients between the ion concentrations, and monthly variations of pH value and precipitation amount are used for chemical analysis on the environmental Pollution and Pollutant sources In Yeoncheon-gun of Kyunggi province near DMZ.

• Journal of Communications and Networks
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• v.18 no.3
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• pp.311-319
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• 2016

In this paper, we analyze the spectrum-sensing performance of a cooperative cognitive radio (CR) network consisting of a number of CR nodes and a fusion center (FC). We introduce the "log-average-SNR ratio" that relates the average SNR of the CR-node-FC link and that of the primary-user-CR-node link. Assuming that the FC utilizes the K-out-of-N rule as its decision rule, we derive exact expressions for the sensing gain and the coding gain - parameters used to characterize the CR network performance at the high SNR region. Based on these results, we determine ways to optimize the performance of the CR network.

• Journal of the Korean Data and Information Science Society
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• v.23 no.4
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• pp.807-814
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• 2012

We know that the exponentially weighted moving average (EWMA) control charts are sensitive to detecting relatively small shifts. Multivariate EWMA control charts are considered for monitoring of variance-covariance matrix when the distribution of process variables is multivariate normal. The performances of the proposed EWMA control charts are evaluated in term of average run length (ARL). The performance is investigated in three types of shifts in the variance-covariance matrix, that is, the variances, covariances, and variances and covariances are changed respectively. Numerical results show that all multivariate EWMA control charts considered in this paper are effective in detecting several kinds of shifts in the variance-covariance matrix.

• Journal of the Korean Data and Information Science Society
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• v.23 no.4
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• pp.859-866
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• 2012

Some switching properties of multivariate control charts are investigated when the interval between two consecutive sample selections is not fixed but changes according to the result of the previous sample observation. Many articles showed that the performances of variable sampling interval control charts are more efficient than those of fixed sampling interval control charts in terms of average run length (ARL) and average time to signal (ATS). Unfortunately, the ARL and the ATS do not provide any information on how frequent a switch is being made. We evaluate several switching properties of two sampling interval Shewhart and CUSUM procedures for controlling mean vector of correlated quality variables.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.12
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• pp.1055-1059
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• 1998

The correlation between the propagation of electrical tree and distributions of partial discharge(PD) pulses accompanying with electrical tree of bush type in low density polyethylene were discussed. We measured the growth of electrical tree by using optical microscope and PD data simultaneously. The PD data detected and analyzed were PD magnitude, repetition rate, average discharge power, average phase angle, and $\psi$-q-n distribution pattern. The average discharge power and repetition rate of PD had good linear relation with area of tree. Repetition rate and peak discharge magnitude and width of discharge phase angle increased with the tree.

• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1562-1568
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• 2014

Based on the average method and the geometrical technique to calculate the average value, the average model of the open-loop step-up converter in CCM operation is established. The DC equilibrium point and corresponding small signal model is derived. The control-to-output transfer function is presented and analyzed. The theoretical analysis and PSIM simulations shows that the control-to-output transfer function includes not only the DC input voltage and the DC duty cycle, but also the two inductors, the two energy-transferring capacitors, the switching frequency and the load. Finally, the hardware circuit is designed, and the circuit experimental results are given to confirm the effectiveness of theoretical derivations and analysis.

• Journal of Information Processing Systems
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• v.13 no.4
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• pp.941-950
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• 2017

The round robin algorithm is regarded as one of the most efficient and effective CPU scheduling techniques in computing. It centres on the processing time required for a CPU to execute available jobs. Although there are other CPU scheduling algorithms based on processing time which use different criteria, the round robin algorithm has gained much popularity due to its optimal time-shared environment. The effectiveness of this algorithm depends strongly on the choice of time quantum. This paper presents a new effective round robin CPU scheduling algorithm. The effectiveness here lies in the fact that the proposed algorithm depends on a dynamically allocated time quantum in each round. Its performance is compared with both traditional and enhanced round robin algorithms, and the findings demonstrate an improved performance in terms of average waiting time, average turnaround time and context switching.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.3
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• pp.231-239
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• 2017

A novel current control technique with fast response and application in an unbalanced system is proposed in this paper. Contrary to the conventional PI and dead-beat current control techniques, the proposed method is adopted to the valley current mode control (VCMC) and average current mode control (ACMC) methods to overcome the phase delay caused by conventional methods. The advantages of the proposed system are simplicity of structure and ease of implementation. The VCMC and ACMC methods are established and applied to the buck converter, boost converter, three-phase PWM converter, and three-phase inverter. The control performances of the proposed systems are shown by computer simulations and verified by experimental results.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.886-888
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• 1993

Recently current mode control is widely adopted in switching power converter because of inherent stablity and ability of parallel operating. There are several ways in current mode control. One of them, peak current control is chiefly employed. Peak current mode control converter usually senses and controls peak inductor current. But there is peak-to-average current errors. Therefore peak current control needs compensation ramp correcting the errors. Average current mode control eliminates these problems, and is constructed by simple structures. This paper will describe the behavior of a simple average current mode boost converter and introduce the design techniques.