• MALSORI
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• no.43
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• pp.179-188
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• 2002

Improving the recognition performance of connected digit telephone speech still remains a problem to be solved. As a basic study for it, this paper analyzes the variation of feature parameters of Korean digit telephone speech according to channel distortion. As a feature parameter for analysis and recognition MFCC is used. To analyze the effect of telephone channel distortion depending on each call, MFCCs are first obtained from the connected digit telephone speech for each phoneme included in the Korean digit. Then CMN, RTCN, and RASTA are applied to the MFCC as channel compensation techniques. Using the feature parameters of MFCC, MFCC+CMN, MFCC+RTCN, and MFCC+RASTA, variances of phonemes are analyzed and recognition experiments are done for each case. Experimental results are discussed with our findings and discussions

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.764-767
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• 2004

The performance of a speech recognition system is generally degraded in telephone environment because of distortions caused by background noise and various channel characteristics. In this paper, data-driven temporal filters are investigated to improve the performance of a specific recognition task such as telephone speech. Three different temporal filtering methods are presented with recognition results for Korean connected-digit telephone speech. Filter coefficients are derived from the cepstral domain feature vectors using the principal component analysis.

• Korean Management Science Review
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• v.9 no.1
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• pp.93-118
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• 1992

This paper addresses the problem of locating a telephone switching center at new establishing city or town. There have been several studies on the location of telephone switching center at an existing telephone network to cope with the expanding subsciber's demand, in most of which only the economic factors were considered and was determined where the switching center is established in order to minimize the total cost. This paper, However, deals with the social factors as well as the economic ones. We develop a location model considered these two factors simultaneously by using a fuzzy approach. Finally, we apply the model to locate a new telephone switching center at the Haeundae where the Pusan City intends to construct a new town.

• Journal of Korea Technology Innovation Society
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• v.1 no.3
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• pp.374-385
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• 1998

This study is estimates telephone service demand based on empirical studies of telecommunication service demand model. First, the telephone charge(call price index) by each location and subscription fee bring about a negative effect to telephone distribution rate: while the other explanatory variables bring about a positive effect. Second, the flexibility of telephone charge in A location(relevant location) and the flexibility between the distance of A location and B location are negative values, while the flexibility of other explanatory variables is represented in a positive value. This means that the long distance call numbers from A location to B location are in inverse proportion against the phone charge(call price index) of A location and against the distance between A location and the distance of other locations except A location, while they are in direct proportion with an average call number per minute from A location to other locations except A location, and also with subscription numbers of A location, other subscribers in locations other than A location, and the total expenditures of A location.

• MALSORI
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• no.53
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• pp.93-102
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• 2005

The performance of a speech recognition system is generally degraded in telephone environment because of distortions caused by background noise and various channel characteristics. In this paper, data-driven temporal filters are investigated to improve the performance of a specific recognition task such as telephone speech. Three different temporal filtering methods are presented with recognition results for Korean connected-digit telephone speech. Filter coefficients are derived from the cepstral domain feature vectors using the principal component analysis. According to experimental results, the proposed temporal filtering method has shown slightly better performance than the previous ones.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.1
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• pp.13-24
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• 1984

This paper presents the measurements and analyses of transmission qualities of the existing urban and toll public switching telephone network (PSTN) for the purllose of opening it to data transmission. In the tests, random noise and impulsive noise occuring on the telephone network are investigated and bit error rate and block error rate representing the transmission qualities on the existing telephone network are measured. We recommend the fastest practical data transmission speed on the network and investigate a possibility of opening the public switching telephone network (PSIN) to the data transmission based on the above measurements.

• The Korean Journal of Emergency Medical Services
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• v.14 no.2
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• pp.5-12
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• 2010

Purpose : The comparative effectiveness of without dispatcher-assisted telephone instruction CPR but received lectured and training(NDCPR) and without received lectured and training CPR but dispatcher-assisted telephone instruction(DCPR) in CPR. Methods : The CPR instruction to 774 students and faculties in universities and colleges. There selected without dispatcher-assisted telephone instruction CPR but received lectured and training(NDCRP) and without received lectured and training CPR but dispatcher-assisted telephone instruction(DCPR). Compare the effectiveness to sills performance of DCPR and NDCPR students and faculties of according to the CPR. Results : 397(51%) students and faculties was DCPR and 377(49%) students and faculties was NDCPR. There was no difference in the compression depth, hand position, adequacy of recoil, volume of ventilation, self-confidence, and willingness to do CPR between the two instructional methods. Conclusion : Under the guide of dispatcher-assisted CPR instruction integrated into mobil phone, novice could perform more effective CPR. This method could be used as a supplement to CPR practice and skill retention.

• Proceedings of the KSPS conference
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• 2003.05a
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• pp.115-118
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• 2003

Channel distortion and coarticulation effect in the connected digit telephone speech make it difficult to recognize, and degrade recognition performance in the telephone environment. In this paper, as a basic research to improve the recognition performance of Korean connected digit telephone, error patterns are investigated and analyzed. Telephone digit speech database released by SITEC with HTK system is used for recognition experiments. Both DWFBA and MRTCN methods are used for feature extraction and channel compensation, respectively. Experimental results are discussed with our findings.

• Survey Research
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• v.9 no.3
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• pp.55-69
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• 2008

In most telephone surveys in Korea, telephone numbers are selected from the directories. Inevitably, such samples may lack representativeness due to poor coverage rate. To resolve the problem, Kang et al.(2008) implemented RDD(random digit dialing) method for nationwide sampling in Korea. The aim of this study is to compare an RDD sample with a traditional telephone quota sample that were collected independently by two survey institutes commissioned by the KBS-MBC consortium for the 2007 Presidential Election of Korea.

• Research in Community and Public Health Nursing
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• v.22 no.3
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• pp.223-233
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• 2011

Purpose: The purpose of this study was to explore and understand customized home visiting nurses' experiences in telephone visiting. Methods: Qualitative data were collected from several discussions of 4 focus groups consisting of 20 customized home visiting nurses. All interviews were recorded and transcribed according to thematic content analysis processes. Results: The five main themes on customized home visiting nurses' experiences of telephone visiting were 'greeting', 'counseling', 'using strategies', 'maintaining attitude for enhancing relations' and 'enduring difficulties'. The category of 'counseling' was composed of confirming, educating, supporting, adjusting, and indicating. And, the category of 'using strategies' included complimenting, scolding, persuading, compensating, and ignoring. Conclusion: Developing a standardized manual on telephone visiting is needed to guide an effective counseling. In order for a customized home visiting nurse to be a good telephone counselor, training of motivational interviewing is recommended.