• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.4
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• pp.24-30
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• 1984

Group delay distortion (phase distortion) is a characteristic which is of no account from a standpoint of voice transmission. But this distortion becomes the major source of distortion in wave form transmission such as data, FAX and others over the public switching telephone network (voice band transmission) so that it must be drastically studied. This paper makes analysis of group deray distortion of the telephone network, describs experimental and measuring results and refers also to the improvement of distortion for the purpose of opening the public switching telephone network to data transmission.

• ETRI Journal
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• v.10 no.4
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• pp.146-160
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• 1988

The purpose of the present study is to build a model to determine the structure of long-term quasi-optimal rates of local and toll telephone services. The outline of this study is as follows : Telephone business, providing social goods, is capital-intensive industry which needs huge fixed cost to operate exchanges and telephone networks nationwide. The nature of above industry justifies the market structure of telephone business to be natural monopoly and makes a good reason for government's direct regulation, that is, price regulation. Three is a gap between the present rates and the quasi-optimal ones because some administrative processes intervene in rate making process before execution. On the above diagnostic basis, the present study made an empirical test for the optimality of present rates structure in connection with Ramsey-Boiteux model to maximize the sum of producer's and consumer's surplus and also the current study proposed a qusasi-optimal rates structure for better market performance. From the empirical analysis, we can deduce a policy recommendation the local price should be increased to 47% whereas toll price decreased to 24% in order to improve the net welfare worth of 32.6 billion won.

• Asian Journal for Public Opinion Research
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• v.3 no.3
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• pp.111-130
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• 2016

Researchers have been perplexed by the issue of unit nonresponse since the beginning of practicing survey research and have been attentive to the causes that lead to the occurrence of unit nonresponse as well as the impact of unit nonresponse. However, because researchers have little to no information regarding unit nonrespondents, it is unlikely that they are able to examine the differences between participants and nonrespondents to estimate the loss of representativeness in the final sample compared with the target population. Therefore, the lack of information regarding the absentees complicates addressing the unit nonresponse bias in a satisfactory manner. Therefore, the purpose of this study was to determine the demographic characteristics and political attitudes of nonrespondents by relying on information provided by their spouses, which was obtained through a telephone survey conducted in Taiwan. It is found that demographic variables as well as political attitudes are related to the likelihood of an individual becoming a unit nonrespondent in telephone surveys.

• Annals of Clinical Neurophysiology
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• v.7 no.2
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• pp.141-142
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• 2005

Two cases of bilateral ulnar neuropathies caused by telephone overuse are described in people engaged in the job of longtime telephone use. They had worked using telephone all through the working hours. Although they were right handed, they usually used the telephone in their left hand so as to leave their right hand free for writing, and would lean his elbow on the desk. Telesales or teleconsultation is a rapidly expanding field of business. These cases highlights the need of proper training and supplies appropriate to do their job.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.47-47
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• 2000

Most measuring devices are equipped with RS-232 or GPIB interface for communicating data with computers. If the measuring devices can be accessed by a server computer, the valuable information from the devices can be effectively shared with other computers via internet. But, if the measuring devices and the server computer are too far away, it is difficulty to directly connect them by RS232 interface. PSTN(Public Switched Telephone Network) refers to the world's collection of interconnected voice-oriented public telephone networks. Measuring computer system which is equipped with RS232 interface and modem for PSTN can be introduced to overcome the aforementioned distance problem, In this work, an internet based remote monitoring system which utilizes PSTN and VRML for 3-dimensional GUI is proposed.

• Speech Sciences
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• v.2
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• pp.57-66
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• 1997

This paper studies the effects of the method, CMS(Cepstral Mean Subtraction), (which compensates for some of the speech distortion. caused by telephone channels), on the performance of the text-dependent speaker identification system. This system is based on the VQ(Vector Quantization) and HMM(Hidden Markov Model) method and chooses the LPC-Cepstrum and Mel-Cepstrum as the feature vectors extracted from the speech data transmitted through telephone channels. Accordingly, we can compare the correct recognition rates of the speaker identification system between the use of LPC-Cepstrum and Mel-Cepstrum. Finally, from the experiment results table, it is found that the Mel-Cepstrum parameter is proven to be superior to the LPC-Cepstrum and that recognition performance improves by about 10% when compensating for telephone channel using the CMS.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.5 no.7
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• pp.43-48
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• 1982

As the result of processing improvement of Telephone Dial by substituting. Synthetic Resin for metalic materials, improved characteristics of quality can be gained as follow. 1. By the improvement of structure and assembling of the Telephone Dial, the complex process of manufacture can be a simplified one, and at the same time the working process can be done in the form of assembly. 2. In the efficiency test of the Telephone Dial, the noise decreases by 5% compared with the first test. In the test of life and environment, it accords with the standard of the Ministry of Communications and its function betters. 3. By using synthetic resins instead of metalic materials the cost can be reduced by \340 than the first improvement and it also brings the heightend value.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06a
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• pp.1064-1069
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• 1994

In order to realize the function of human interface of telecommunications whose objective is to interchange useful information among persons, we developed a bone conduction telephone with which hearing impaired persons with conductive or noise-induced hearing loss and presbycusis can communicate with each other without any other additional devices such as hearing aids. The bone conduction telephone we developed has chatacteristics as follows : (i) a hearing impaired person and a normal hearing person can communicate by bone and air conduction hearings, respectively, using only this telephone set because, as its receiver, it uses a bone conduction vibrator with which we can realize such function with the voice coil and damper of a small speaker unit, the vibrating plate, etc., (ii) it has tone control function compensating hearing losses of hearing impaired persons according to their hearing loss/frequency chatacteristics. Using the tone control function together with a received volume control, it has the received volume range of 20dB in loudness rating; and (iii) it has the function of three emergency calls and a bell lamp as the visual display of a received call.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.13 no.1
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• pp.50-59
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• 2006

Purpose: This study was conducted from January to March, 2004 to examine the effect of telephone follow-up on the performance of self-care in cancer patients undergoing chemotherapy and on role stress of family caregivers. Method: Research design was a nonequivalent control group non-synchronized design. Seventy-two participants were assigned to either the experimental group (18 cancer patients, 18 family caregivers) or the control group (18 cancer patients, 18 family caregivers). Data were collected before and after the intervention and were analyzed with paired t-test, t-test, Mann-Whitney U Test & Wilcoxon Signed Ranks Test. Results: Performance of self-care in the experimental group undergoing telephone follow-up was significantly higher than that of the control group (t=8.016, p=0.000). Role stress of family members in the experimental group was also significantly higher than that of the control group (t=2.133, p=0.042). Conclusion: This results suggest that the telephone follow-up is effective for cancer patients undergoing chemotherapy and their family caregivers. Telephone follow-up can be recommended as an effective nursing intervention for self-care performance in cancer patients undergoing chemotherapy and to reduce role stress of family caregivers.

• Journal of Preventive Medicine and Public Health
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• v.33 no.1
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• pp.109-116
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• 2000

Objectives : Routine vaccination against influenza is recommended for all people aged 65 years or more. Without active encouragement to receive the vaccine, the rate of compliance is generally low. A study was undertaken to assess and compare the effectiveness of two reminder systems in improving the influenza vaccination rate. Methods : A total of 2,017 patients aged 65 or over in a tertiary care hospital family practice center were randomly assigned to a control, a telephone reminder, or a postcard reminder group before the influenza season in 1998. The outcome measure, receipt of vaccination, was determined by telephone interview. Demographic and clinical characteristics were checked through the medical chart review. Results : Among the 1,312 patients who actually received reminders and interviewed, the vaccination rate was 46.7% in the control group, 56.3% in the postcard reminder group, and 63.3% in the telephone reminder group. Vaccination compliance was significantly higher in people reminded by telephone (Odds ratio [OR], 2.00; 95% confidence interval [CI], 1.52-2.64) and postcard (OR, 1.55; 95% CI, 1.18-2.02) compared to that in the control group. Of the characteristics investigated, number of high risk co-morbidity was positively associated with vaccination compliance while current smoking was negatively associated. Conclusions : This result suggests that telephone and postcard reminders can significantly improve compliance with influenza vaccination in this group of Korean elderly. However, additional strategies need to be developed to encourage vaccination among noncompliant.