• Journal of The Institute of Information and Telecommunication Facilities Engineering
• /
• v.9 no.1
• /
• pp.24-28
• /
• 2010

The Quality of Experience (QoE) of next Generation wired/wireless network services based upon IP networking is becoming a popular issue in recent years. The user experience of Internet services such as IPTV, online game, web surfing and etc, are becoming the most desirable factors to service providers to improve service performance and customer's satisfaction. However, collecting user experience from customers and obtaining the QoE parameters from the Quality of Service (QoS) parameters such as bandwidth, delay, jitter or admission control algorithm, are difficult subjects because of the various service types and user characteristics. In this paper, we propose a framework which contains service classification, QoE analysis and service enhancement steps for a suitable QoE measurement and management protocol. We define the user satisfaction indicators of the Internet services, classify the categories of each type of services, and analyse the Key Performance Indicator (KPI) in each type of services to perform the QoS parameters and improving the service qualities.

• Proceedings of the KIEE Conference
• /
• 2000.11b
• /
• pp.348-351
• /
• 2000

There have been significant advances in thyratron performance in recent years. these advanced waveforms have increased the complexity and cost of drive circuits. Thyratrons can reliably switch anode voltages up to 40kV and conduct peak currents up to 10kA or more. So stable thyratron drivers are essential for reliable high voltage pulse modulators. In order to operate thyratron well, thyratron driver need high repetition rate, fast rising time and low jitter. In this paper, used power MOSFET/transformer combinations. Designed thyratron driver is satisfied requirements and experimental results are presented to confirm.

• Annual Conference of KIPS
• /
• 2020.05a
• /
• pp.180-183
• /
• 2020

물리적 정보를 이용해 암호 알고리즘의 비밀정보를 분석하는 부채널분석 분야에서도 딥러닝을 접목한 분석방법들이 활발히 제안되고 있다. 본 논문에서는 소비전력이 시간축상으로 흐트러지는 현상인 지터가 있는 파형을 신경망의 특성을 기반으로 효과적으로 분석하는 방법을 제안한다. 제안한 방법을 실험적으로 검증하기 위해 지터가 있는 AES-128 파형을 Convolutional Neural Network와 Multi-Layer Perceptron을 기반으로 분석한 결과 제안한 방법을 적용한 신경망은 모든 바이트 키 분석에 성공했으나, 이외의 신경망은 일부 혹은 모든 바이트 키 분석에 실패했다.

• The KIPS Transactions:PartB
• /
• v.18B no.6
• /
• pp.397-404
• /
• 2011

In this paper, we were carried out experiments to apply parameter of voice analysis to measure changing characteristic articulator according to inhale the helium gas. The helium gas was used to overcome air embolism nitrogen gas to deal a fatal blow in body nitrogen gas by diver. However, the helium gas has been much trouble interpretation about abnormal voice of diver to cause squeaky voice of low articulation. Therefor, we was carried out experiments about pitch and spectrogram measurement, analysis based on to influence in acoustic organs before and after of inhaled helium gas.

• Phonetics and Speech Sciences
• /
• v.5 no.4
• /
• pp.71-78
• /
• 2013

The purpose of this study was to compare the acoustic voice outcomes of children with cochlear implant to those of children with normal hearing. Participants were 41 children using unilateral cochlear implant (18 males and 23 females), and children with normal hearing from the same age and sex. Mean age of implantation was approximately 3 years old, mean duration of implant use was 4 years in CI group. Acoustic analyses were performed using MDVP of CSL. Speech samples were 3 sustained vowels, /a, i, u/. 9 parameters (F0, Fhi, Flo, Jitter, Shimmer, vF0, vAm, NHR, and SPI) were analyzed. Children with CI did not show the significant differences in those parameters after the vowel /a/ phonation. Meanwhile, there were significantly different results in F0, Fhi, vF0, and SPI after /i, u/ phonation. These results revealed that differences of voice characteristics in children with CI compare to children with NH persist regarding vowel context. It suggests that high vowels would recommend as speech samples for acoustic evaluation. Futhermore perceptual analysis and speech therapy for phonation control would be necessary for children with CI.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.10 no.1
• /
• pp.17-23
• /
• 1999

Vocal hyperfunction is considered to be the most significant characteristic in larynx disorders which is found among many patients presenting hoarseness Primarily as chief complaint. In Pusan National University Hospital, we executed the voice therapy to 28 patients being 17 female and 11 male patients who visited the Voice ＆ Speech Therapy Clinic, due to the voice disorder, and then compared and analysed the voice before and after its therapy using acoustic and aerodynamic test. The obtained results were as follows. In the analysis by the local findings, it was improved to 88% in the patients of vocal nodule, 75% in mutational falsetto, 75% in the functional dysphonia, 75% in the vocal cord palsy, 50% in the vocal polyp and 50% in dysphonia plica ventricularis. For the acoustic analysis, Fo, litter, Shimmer and NHR were measured. In the patients of mutational falsetto, Fo, Jitter and NHR were shown to be improved significantly and in the patients of vocal nodule, Shimmer was shown to be improved significantly. In the patients of vocal polyp, Fo was significantly improved. In the patients of vocal cord palsy in litter and NHH were significantly improved. In the patients of dysphonia plica ventricularis, Shimmer and NHR were significantly improved and the patients of functional dysphonia were more improved in Fo, litter and Shimmer. For the aerodynamic analysis, MPT was measured. In particular, it was shown to be improved significantly in the patients of vocal nodule, improved in the vocal polyp, vocal cord palsy, functional dysphonia patients.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.22 no.2
• /
• pp.143-150
• /
• 2011

Background and Objectives : Clinically, as a tool for voice assessment before and after the operation or the voice treatment, acoustic analysis is widely used. However, in clinical situations, acoustic parameters vary according to how the assessment is made. Thus, with voice disease patients as subjects, we are to investigate what influence intensity increase exerts on acoustic parameters and how to reduce variation according to the way of assessing. Material and Method : At the voice clinic of the department of otorhinolaryngology in Gangnam Severance Hospital, with 30 female voice-disease patients (40.6 years old on the average) and 23 male voice-disease patients (40.1 years old on the average) as subjects, using the Dr Speech vocal-assessment program, we statistically tested the significance of the difference in each of acoustic parameters between when the "Ah" vowel is produced with a normal voice and when the "Ah" vowel is produced with a loud voice. Results : Acoustic parameters that showed a statistically significant difference according to intensity increase were Jitter, SD F0, and NNE for females, and Jitter, SD F0, HNR, SNR, and NNE for males. Voice quality estimates showed a statistically significant difference according to intensity increase in female hoarse voice, female breathy voice, and male breathy voice. Conclusion : In this research, acoustic analysis, which is generally used for voice assessment before and after the operation or the voice treatment, showed a tendency that acoustic parameters became better under the influence of intensity increase except for the cases where a voice disease was severe. Thus, to raise the reliability of voice assessment, the range of intensity needs to be set up. This should be the topic for the future research.

• Phonetics and Speech Sciences
• /
• v.7 no.1
• /
• pp.79-86
• /
• 2015

This study explored the vowel effect on acoustic perturbation measures in voice quality analysis. For this study, the perturbation parameters (%jitter, %shimmer) and noise parameter (SNR) were measured with 7 Korean vowels (/a/, /ɛ/, /i/, /o/, /u/, /ɯ/, /ʌ/) using CSpeech with 50 Korean normal young adults (24 males and 26 females). A significant vowel effect was found only in %shimmer and in particular, low-back /a/vowel was significantly different from other vowels in %shimmer. The least perturbation and noise were exhibited on high-back /ɯ/ and /o/ vowel, respectively. Based on tongue height, a significant higher %shimmer was demonstrated on low vowels than high vowels. In addition, back vowels in tongue advancement and rounded vowels in lip rounding showed significantly less perturbation and noise. The least variability of perturbation and noise within individuals was demonstrated on the vowel /i/ in three repeated measures. However, there was no significant difference among 3 token measures in single session among vowels tested except the vowel /o/. Consequently, the vowel /a/ commonly used in acoustic perturbation measures exhibited higher perturbation and noise whereas higher stability and less variability were demonstrated on the high-back vowel /u/. These results suggested that the Korean high-back vowel /u/ can be more appropriate and reliable for perturbation acoustic measures.

• Phonetics and Speech Sciences
• /
• v.5 no.4
• /
• pp.25-32
• /
• 2013

This research is aimed at finding the acoustic characteristics of different voice rehabilitation techniques, the electrolaryx (EL), standard esophageal (SE), and tracheoesophageal (TE), used on 17 patients with laryngectomees. The analysis of the voice qualities was achieved using MDVP. In order to compare the acoustic characteristics, patients were asked to produce the vowel /a/ sound. The acoustic analysis included fundamental frequency (f0), jitter, shimmer, and noise-to-harmonic ratio (NHR). The main acoustic results showed no significant statistical differences between the average measurements of SE and TE speakers. It was found that the current study showed the same tendency found in previous studies. There was also a significant difference between SE and EL speakers. On the other hand, there were no significant statistical differences between the average measurements of TE and EL speakers on all acoustic measurements. This research will contribute to establishing a baseline related to speech characteristics in voice rehabilitation for patients with laryngectomees. In future, the present findings and issues should be considered in the context of gender. Specifically, the number of women who are diagnosed with laryngeal cancer continues to rise and their acoustic characteristics may indeed differ from those of men.

• Speech Sciences
• /
• v.15 no.4
• /
• pp.159-170
• /
• 2008

The purpose of this study was to find out the ability of coordination of the articulatory motor and the ability of control of the respiration and laryngeal for spastic dysarthria by acoustic analysis. The sustained of vowel /a/ and repetition of syllable /pa/ in 15 normal and 10 spastic dysarthria were measured. Multi-Speech, MDVP, and MSP were used for data recording and analysis. As a result, the mean DDK rate in the spastic group was significantly slower than in the normal. The maximum phonation time in the spastic group ($4.80{\pm}1.94$) was shorter than in the normal ($11.20{\pm}3.72$). The DDKjit in the spastic group was significantly higher than in the normal. The DDKsla was reduced in the spastic group. The mean syllable duration in the spastic group (146.2ms) was significantly longer than in the normal (75.8ms). The mean energy was reduced in the spastic group. The range of Fo was greater than in the normal. The frequency perturbation (jitter, vFo) and amplitude perturbation (shimmer, vAm) were higher than in the normal group. The NHR was higher than in the normal group. The parameters of this were significantly difference between the spastic dysarthria and the normal (p<0.05). Finally, the spastic dysarthria has short respiration, slow speech rate, and voice quality problem. The these results will help to establish a plan and the intervention of treatment.