• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.13 no.1
• /
• pp.49-54
• /
• 2013

WPM(Wavelet Packet Modulation) is multicarrier system which is suitable for high speed transmission. The main advantage of using the WPM system is the fact that the flexible system effectively can be realized by the combination of filter coefficient. On the other hand, the major problem of multicarrier system is known to be the high PAPR. In this paper we propose WPM system that has a minimum PAPR by using filter coefficient adjustment method. We first derive the filter coefficient equation and then select the coefficient that has a minimum PAPR. we conduct WPM system by using a selected coefficient and we demonstrate the system performance by using computer simulation.

• 한국어정보학회:학술대회논문집
• /
• 2016.10a
• /
• pp.291-295
• /
• 2016

본 논문에서는 한국어 기본 유니트 단위로 WPM을 활용한 구글 플레이 스토어 앱의 댓글 감정분석을 수행하였다. 먼저 자동 띄어쓰기 시스템을 적용한 후, 어절단위, 형태소 분석기, WPM을 각각 적용하여 모델을 생성하고, 로지스틱 회귀(Logistic Regression), 소프트맥스 회귀(Softmax Regression), 서포트 벡터머신(Support Vector Machine, SVM)등의 알고리즘을 이용하여 댓글 감정(긍정과 부정)을 비교 분석하였다. 그 결과 어절단위, 형태소 분석기보다 WPM이 최대 25%의 향상된 결과를 얻었다. 또한 분류 과정에서 로지스틱회귀, 소프트맥스 회귀보다는 SVM 성능이 우수했으며, SVM의 기본 파라미터({'kernel':('linear'), 'c':[4]})보다 최적의 파라미터를 적용({'kernel': ('linear','rbf', 'sigmoid', 'poly'), 'C':[0.01, 0.1, 1.4.5]} 하였을 때, 최대 91%의 성능이 나타났다.

• Annual Conference on Human and Language Technology
• /
• 2016.10a
• /
• pp.291-295
• /
• 2016

본 논문에서는 한국어 기본 유니트 단위로 WPM을 활용한 구글 플레이 스토어 앱의 댓글 감정분석을 수행하였다. 먼저 자동 띄어쓰기 시스템을 적용한 후, 어절단위, 형태소 분석기, WPM을 각각 적용하여 모델을 생성하고, 로지스틱 회귀(Logistic Regression), 소프트맥스 회귀(Softmax Regression), 서포트 벡터머신(Support Vector Machine, SVM)등의 알고리즘을 이용하여 댓글 감정(긍정과 부정)을 비교 분석하였다. 그 결과 어절단위, 형태소 분석기보다 WPM이 최대 25%의 향상된 결과를 얻었다. 또한 분류 과정에서 로지스틱회귀, 소프트맥스 회귀보다는 SVM 성능이 우수했으며, SVM의 기본 파라미터({'kernel':('linear'), 'c':[4]})보다 최적의 파라미터를 적용({'kernel': ('linear','rbf', 'sigmoid', 'poly'), 'C':[0.01, 0.1, 1.4.5]} 하였을 때, 최대 91%의 성능이 나타났다.

• ETRI Journal
• /
• v.41 no.2
• /
• pp.184-196
• /
• 2019

Wavelet packet modulation (WPM) is a multicarrier modulation (MCM) technique that has emerged as a potential alternative to the widely used orthogonal frequency-division multiplexing (OFDM) method. Because WPM has overlapped symbols, equalization cannot rely on the use of the cyclic prefix (CP), which is used in OFDM. This study applies linear minimum mean-square error (MMSE) equalization in the time domain instead of in the frequency domain to achieve low computational complexity. With a modest equalizer filter length, the imperfection of MMSE equalization results in subcarrier attenuation and noise amplification, which are considered in the development of a bit-loading algorithm. Analytical expressions for the bit error rate (BER) performance are derived and validated using simulation results. A performance evaluation is carried out in different test scenarios as per Recommendation ITU-R M.1225. Numerical results show that WPM with equalization-aware bit loading outperforms OFDM with bit loading. Because previous comparisons between WPM and OFDM did not include bit loading, the results obtained provide additional evidence of the benefits of WPM over OFDM.

• Speech Sciences
• /
• v.9 no.4
• /
• pp.93-103
• /
• 2002

The purpose of this study was to establish preliminary data on the speech rates in groups of normal speaking adults and children. The results of the present study are intended to serve as clinical measurement guidelines for diagnosis, assessment, treatment planning, and therapy progresses of stuttering. Thirty-one adults (16 females, 15 males), aged 18-30 years and thirty normally developing children (15 females, 15 males), aged 8-10, participated in the study. The subjects' reading of the Stroll (Jeong, 1994) passage and l-minute portion of talking about the daily routine were sampled. The adult speakers had rates of $308.29\pm22.57$ syllables per minute (SPM) or $108.06\pm6.17$ words per minute (WPM) during reading, and $252.87\pm40.86$ SPM and $92.26\pm17.12$ WPM during talking. The children had rates of $176.67\pm33.65$ SPM or $64.07\pm12.62$ WPM during reading, and $149.30\pm33.14$ SPM and $56.60\pm11.36$ WPM during talking. The results of t-tests for reading and talking tasks in adults showed that SPM in reading (t=2.211, p< .05) and WPM in talking (t=-2.284, p< .05) differed significantly by the gender. To answer the questions whether the rate is different across children' s gender and age, a two-way ANOVA was performed. Both SPM and WPM in reading tasks were significantly different between groups of children aged 8 and 10 (p< 01), In speaking tasks, both SPM and WPM were significantly different between groups of children aged 8 and 10, and between 9 and 10.

• Proceedings of the KIEE Conference
• /
• 2008.10c
• /
• pp.29-31
• /
• 2008

단상 유도형 동기전동기(Line-Start Permanent Magnet Motor: LSPM)는 기존의 단상유도기에 비해 높은 효율을 갖고 있어 가정에서의 주요 동력원으로 사용되고 있다. 그러나 기동 시 영구자석에 의한 Braking toruqe의 발생으로 인해 높은 기동토크를 필요로 하는 단점을 갖고 있다. 본 논문에서는 이러한 LSPM의 장점과 기동 시의 문제점 극복에 유리한 Written-Pole Motor (WPM)에 대해 소개하였다 또한 WPM의 보다 정화한 해석을 위해 WPM의 특징인 운전시 진행되는 영구자석 착자의 유한요소해석을 통해 영구자석의 잔류자속밀도를 계산하였으며 이를 바탕으로 WPM의 동기속도에서의 정특성 해석을 수행하였다.

• Journal of Korean Society of Forest Science
• /
• v.97 no.1
• /
• pp.127-133
• /
• 2008

This study was conducted to establish the optimal condition for plant regeneration and acclimatization from somatic embryos of Panax ginseng. Cotyledon segments of Panax ginseng produced primary and secondary somatic embryos when cultured on MS and WPM media supplemented with 7% sucrose. To induce plantlet conversion, cotyledonary somatic embryos were cultured on WPM solid medium with $GA_3$ at various concentrations (1~30 mg/L) for 4 weeks. Plantlets were transferred to 1/2 WPM solid medium with $GA_3$ at various concentrations (0~5 mg/L) and 0.5% activated charcoal for shoot and root elongations. Elongated plantlets further developed into well-developed leaf and root system on 1/3 SH medium with 0.5% activated charcoal under ventilation condition for 5 months. The highest survival rate to soil was 75% when plantlets were regenerated on 1/3 SH medium without sucrose under ventilation condition.

• Journal of Korean Society of Forest Science
• /
• v.99 no.4
• /
• pp.568-572
• /
• 2010

In order to develop an efficient micropropagation system for a rare tree species, Empetrum nigrum var. japonicum K. Koch, the effect of medium salt, cytokinins and auxin at different concentration were evaluated. Shoot induction from axillary bud was better on WPM medium than on MS medium. Although there was no significant differences observed in shoot induction among the salt strengths of WPM medium, whereas healthy shoots were developed on basal WPM medium. In comparison of the cytokinins affecting shoot proliferation, zeatin was better than BA, whereas BA exhibited more effectiveness on shoot elongation. In vitro root formation was better on WPM medium than on 1/2MS medium and achieved the highest rooting rate when 5.0 mg/L IBA treatment. 93% of rooted plantlets were survived on artificial soil mixture after 4 weeks of acclimatization. Above results suggest that a rare tree species, E. nigrum var. japonicum can be micropropagated via axillary bud cultures.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.916-917
• /
• 2011

본 논문에서는 WPM의 기동시 감자된 영구자석을 착자시키는 exciter pole의 최적설계에 대해 다룬다. 영구자석형 동기전동기의 성능을 결정짓는 자석의 잔류자속밀도를 최대로 만들기 위하여 반응표면법을 이용하여 exciter를 설계하였다. 목적함수는 영구자석 중심에서 의 자계의 세기이며 정밀도를 위하여 유한요소법을 통해 결과를 확인하였다.

• 한국어정보학회:학술대회논문집
• /
• 2016.10a
• /
• pp.67-71
• /
• 2016

본 논문에서는 word2vec과 doc2vec을 함께 CNN에 적용한 문서 분류 방안을 제안한다. 먼저 어절, 형태소, WPM(Word Piece Model)을 각각 사용하여 생성한 토큰(token)으로 doc2vec을 활용하여 문서를 vector로 표현한 후, 초보적인 문서 분류에 적용한 결과 WPM이 분류율 79.5%가 되어 3가지 방법 중 최고 성능을 보였다. 다음으로 CNN의 입력자질로써 WPM을 이용하여 생성한 토큰을 활용한 word2vec을 범주 10개의 문서 분류에 사용한 실험과 doc2vec을 함께 사용한 실험을 수행하였다. 실험 결과 word2vec만을 활용하였을 때 86.89%의 분류율을 얻었고, doc2vec을 함께 적용한 결과 89.51%의 분류율을 얻었다. 따라서 제안한 모델을 통해서 분류율이 2.62% 향상됨을 확인하였다.