• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.10
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• pp.8-12
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• 2007

In this paper, we proposed an frequency offset estimation scheme which can be used for packet based OFDM communication systems such as IEEE802.11a and IEEE802.11p physical layer. Proposed estimation scheme can adjust the gain allocation ratio between long training symbol and short training symbol while maintaining average power of overall training sequence so that we can obtain the reference parameters for MSE performance improvement. The preamble structure considered in this paper is based on the preamble specified in IEEE802.11a and IEEE802.11p standardization group. From the simulation results, it is shown that power ratio between long training symbol and short training symbol must vanes for achieving lower frequency offset estimation error as channel SNR condition is changed. Also it is known oat proposed scheme can achieve better performance than conventional one.

• The Research Journal of the Costume Culture
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• v.7 no.4
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• pp.155-167
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• 1999

The present study investigated various sales training programs used by apparel companies and compared each other in order to provide an important information for developing effective training programs for professional salesperson. Sixty eight companies were used and grouped into four categories based on brand characteristics : domestic national brand(DNB), casual brand(CB), foreign brand(FB) and domestic designer brand(DDB). Data were collected from the managers in charge or training salesperson by both questionnaires and personal and telephone interviews. Data were collected during July in 1998, and analyzed by using ANOVA, Duncan\`s multiple range test, and Chi-square test. Since the sample size was small, Yates\` correction formula was used to maximize statistical validity in non-parametric procedure of Chi-square test. The main purpose of sales training indicated by the companies were to satisfy customers and to maximize the profit. Significant differences were found among the groups in the importance level of training contents such as knowledge, and customer relation, training methods, place, and duration/frequency of training at training center.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.971-972
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• 2010

• Annals of Rehabilitation Medicine
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• v.42 no.6
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• pp.777-787
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• 2018

Objective To examine the long-term effects of the low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) combined with task-specific training on paretic hand function following subacute stroke. Methods Sixteen participants were randomly selected and grouped into two: the experimental group (real LF-rTMS) and the control group (sham LF-rTMS). All the 16 participants were then taken through a 1-hour task-specific training of the paretic hand. The corticospinal excitability (motor evoke potential [MEP] amplitude) of the non-lesioned hemisphere, and the paretic hand performance (Wolf Motor Function Test total movement time [WMFT-TMT]) were evaluated at baseline, after the LF-rTMS, immediately after task-specific training, 1 and 2 weeks after the training. Results Groups comparisons showed a significant difference in the MEP after LF-rTMS and after the training. Compared to the baseline, the MEP of the experimental group significantly decreased after LF-rTMS and after the training and that effect was maintained for 2 weeks. Group comparisons showed significant difference in WMFT-TMT after the training. Only in the experimental group, the WMFT-TMT of the can lifting item significantly reduced compared to the baseline and the effect was sustained for 2 weeks. Conclusion The results of this study established that the improvement in paretic hand after task-specific training was enhanced by LF-rTMS and it persisted for at least 2 weeks.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.6
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• pp.290-297
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• 2014

The synchronization of OFDM receiver is consisted of symbol timing offset(STO) estimation in time domain and carrier frequency offset(CFO) estimation in frequency domain. This paper proposes new algorithm for correcting the integer CFO after we have done correcting the STO and partial CFO. ICFO must be corrected, since the ICFO lead to degrade bit error rate(BER) of demodulation performance. The PN sequence has information which is subcarrier order since the modified PN sequence, length is same subcarrier, is used in this paper and is modulated each subcarrier by each chip. Thus the receiver track phase of PN sequence after FFTin order to find the subcarrier frequency offset. The proposed algorithm is faster and more simple than convenient methode as measuring carrier energy.

• Speech Sciences
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• v.9 no.1
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• pp.7-16
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• 2002

This study tested normal hearing adults' auditory perception of rhythm and intonation patterns, with low-frequency speech energy. The results showed that the narrow-band low-frequency zones of 125, 250, or 500 Hz provided the same important rhythm and intonation cues as did the wide-band condition. This suggested that an auditory training strategy that uses low-frequency filters would be effective for structuring or re-structuring the perception of rhythm and intonation patterns. These filters force the client to focus on these patterns, because the speech intelligibility is drastically reduced. This strategy can be used with both normal-hearing and hearing impaired children and adults with poor listening skills, and possibly poor speech intelligibility.

• The Journal of Korean Physical Therapy
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• v.28 no.4
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• pp.243-248
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• 2016

Purpose: This study was conducted to identify the effects of neuromuscular training performed on badminton club members' to improve muscle activity of the lower extremities and static and dynamic balance tests. Methods: The subjects were 20 badminton club members with chronic ankle instability who were randomly divided into a neuromuscular training group and a balance training group, each with 10 patients. Both exercises ware performed three days per week for 30 minutes a day over six weeks. Results: The neuromuscular training group showed increased muscle activity of the lower extremities compared to the balance training group. Neuromuscular training increased balance ability better than the balance training group, showing a significant difference and better efficiency of neuromuscular training when compared to balance training. Conclusion: This research evaluated neuromuscular training as an intervention for badminton club members with chronic ankle instability and compared the differences in muscle activity of the lower extremities and balance ability; as a result of the effective frequency for improving performance, there was a significant difference in muscle activity of lower extremities and balance ability of the neuromuscular training group and the control group.

• Physical Therapy Korea
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• v.10 no.3
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• pp.17-27
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• 2003

Repetitive transcranial magnetic stimulation (rTMS) modulates cortical excitability beyond the duration of the rTMS trains themselves. Depending on rTMS parameters, a lasting inhibition or facilitation of cortical excitability can be induced. Therefore, rTMS of high or low frequency over motor cortex may change certain aspects of motor learning performance and cortical activation. This study investigated the effect of high and low frequency subthreshold rTMS applied to the motor cortex on motor learning of sequential finger movements and brain activation using functional MRI (fMRI). Three healthy right-handed subjects (mean age 23.3) were enrolled. All subjects were trained with sequences of seven-digit rapid sequential finger movements, 30 minutes per day for 5 consecutive days using their left hand. 10 Hz (high frequency) and 1 Hz (low frequency) trains of rTMS with 80% of resting motor threshold and sham stimulation were applied for each subject during the period of motor learning. rTMS was delivered on the scalp over the right primary motor cortex using a figure-eight shaped coil and a Rapid(R) stimulator with two Booster Modules (Magstim Co. Ltd, UK). Functional MRI (fMRI) was performed on a 3T ISOL Forte scanner before and after training in all subjects (35 slices per one brain volume TR/TE = 3000/30 ms, Flip angle $60^{\circ}$, FOV 220 mm, $64{\times}64$ matrix, slice thickness 4 mm). Response time (RT) and target scores (TS) of sequential finger movements were monitored during the training period and fMRl scanning. All subjects showed decreased RT and increased TS which reflecting learning effects over the training session. The subject who received high frequency rTMS showed better performance in TS and RT than those of the subjects with low frequency or sham stimulation of rTMS. In fMRI, the subject who received high frequency rTMS showed increased activation of primary motor cortex, premotor, and medial cerebellar areas after the motor sequence learning after the training, but the subject with low frequency rTMS showed decreased activation in above areas. High frequency subthreshold rTMS on the motor cortex may facilitate the excitability of motor cortex and improve the performance of motor sequence learning in normal subject.

• Korean Journal of Human Ecology
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• v.14 no.6
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• pp.1017-1025
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• 2005

The purpose of this paper was to investigate the relationship between customer orientation and sales training. Data were obtained from 297 apparel salespeople working at six department stores in Daegu. Statistics used for data analysis were frequency, factor analysis, correlation, and t-test. The respondents were classified into 3 groups; high, medium, and low customer-oriented groups based on the mean score of customer orientation, and the high and the low were compared in training contents and educational methods. Based on factor analysis, four factors were extracted from 27 items of training content. Two of four factors were significantly correlated with customer orientation. The regression analysis showed that customer service and duration of work had significant effects on customer orientation. Also, the results were found that there were significant differences between the high and the low customer-oriented group in training contents which salespeople want to have in the future. However, there were not significant differences between the two groups in educational methods.

• Korean Journal of Human Ecology
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• v.24 no.1
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• pp.137-148
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• 2015

The purpose of this study was to investigate the kindergarten teachers operation and demand of dietary education in Jeonbuk province. The study was carried out using a self administered questionnaire and the subjects were 148 kindergarten teachers. The questions were general characteristics of the subjects, operating status as frequency, place, education time, and training demand on dietary education. The results are as follows. All subjects were female(100.0%), more than half were 20's(62.8%) in their age, teaching career was 31.8% in less than 3 years, and 68.2% in more than 3 years. Frequency of the dietary education operation was 3 times per week(53.4%), place of education were classroom(81.9%), and education time was lunch time(87.5%). Twenty three point eight percent of the subjects recognized the facilities for education was lack, 32.6% of them did the education materials was lack. The desirable frequency of dietary education was 1~2 times per week(40.4%). About two third of the subjects(73.6%) recognized the objects of the dietary education was not only preschool children but also their parents. Most of the subjects(83.8%) had willing to get training, the proper training program was 10 hours(87.8%), and they prefer semester weekday(64.9%) than semester weekend(30.5%). Proper ratio in the core value of dietary education as environment : health : thanks was 31.8% : 40.9% : 27.2%. It is concluded that the demand on dietary education of kindergarten teachers is necessary for their education program in kindergarten.