• ETRI Journal
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• 제36권5호
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• pp.865-875
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• 2014

Voice phishing (vishing) uses social engineering, based on people's trust in telephone services, to trick people into divulging financial data or transferring money to a scammer. In a vishing attack, a scammer often modifies the telephone number that appears on the victim's phone to mislead the victim into believing that the phone call is coming from a trusted source, since people typically judge a caller's legitimacy by the displayed phone number. We propose a system named iVisher for detecting a concealed incoming number (that is, caller ID) in Session Initiation Protocol-based Voice-over-Internet Protocol initiated phone calls. Our results demonstrate that iVisher is capable of detecting a concealed caller ID without significantly impacting upon the overall call setup time.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.691-694
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• 2000

This paper is addressed to Internet telephony based service implementation. It describes an implementation method which uses ARS as a gateway which combines Internet and traditional public switched telephone network for Internet information service using telephony and fax, is different to traditional Internet telephony which provide enhanced speech quality and low cost functionality. This method allows telephony and/or fax user to get Internet information without additional Internet bill, Internet infrastructure and low connection quality from low signal bandwidth connected him. Implemented system is useful to a special kind information service such as climate information of Korea etc and simpler than WAP based service as for wireless mobile telephony user. We implement job opportunity information and advertisement service supported by Home page of Choong Book Small & Medium Business Administration and e-mail service supported by Korean Society for Rehabilitation of persons with Disabilities to demonstrate the system ability. As a result of test implementation, this service system works good fur blind persons and graduated persons without job, is expected to apply for special Internet information provider via Voice and Fax.

• 대한간호학회지
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• 제26권3호
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• pp.576-590
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• 1996

Advanced countries such as the USA and Japan are eagerly seeking ways to improve health and welfare of the elderly. One of the services is home health care service using the telephone. Various types of services using the telephone have been developed, improved and are being utilized ranging from the basic consulting to emergency response systems in the area of health care for the elderly. A demonstration project was launched to study the feasibility of a consulting system and telemedicine for the elderly using the public phone system in Korea. For this project, a gathering site for the elderly was selected and those who visited this place were interviewed to find out what kinds of services they wanted and what kind of system they needed to provide the required services. Based on the users' requests and the surrounding environment, a telephone consulting facility was established at the Research Institute of Nursing Science at Seoul National University and consulting personnel was recruited, trained and posted at the center. An Application program for home health care nurses to use when they visited the patients at their homes was developed. This system operates on a notebook Computer and allows nurses to communicate with a doctor at a local hospital through a modem and telecommunication line. These systems were implemented for three months and problems which developed during operation of the systems were identified and progressively modified. Through system evaluation, it was found that a consulting system using phone service will be an invaluable system for the welfare of the elderly in the future. But in order to meet the elderly's need, more services than mere consultation are needed. That is, communication with physicians and hospitals are needed. Thus, when there is any need for physicians' attention, physicians or hospitals should be contacted directly. Similarly for telemedicine, when the home health care nurse visits elderly patients she can assess the patient's problem and provide nursing care, access a physician or hospital to refer her patient to or consult directly using the telecommunication the system. The above mentioned system is a basic form of futuristic telemedicine for the elderly and those who have chronic disease problems. This kind of system will be of great value when it is used on the national information super-highways in the future. In order to get to that stage, of course, this project needs great improvement in the technical, academic, and legal aspects.

• 한국통신학회논문지
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• 제25권10B호
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• pp.1793-1802
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• 2000

In this paper we propose an efficient implementation technique for cyclic extension in VDSL(Very High bit-rate Digital Subscriber Line) systems using Zipper duplexing and analyze its performances under typical telephone channel environments. In Zipper-based VDSL systems each DTM(discrete-multitone) block is appended by both cyclic prefix(CP) and cyclic suffix(CS). The CP is inserte to prevent both intersymbol interference (ISI) and iterchannel interference (ICI) while the CS is appended to ensure orthogonality between the upstream and downstream carriers thus preventing near-end crosstalk (NEXT). However in order to implement the CP in the transmitter side of the VDSL system an additional hardware is required to append the latter part of each DMT symbol to the beginning of the DMT symbol. In this paper we propose a VDSL system with Zipper duplexing using only CS to reduce hardware complexity (memory and processing delay) required for implementation of CP. It is shown by computer simulation that the proposed approach has the same capacity under typical channel environments as the previous Zipper-based VDSL system using both CP and CS. even with a significantly lower hardware complexity.

• 대한의용생체공학회:의공학회지
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• 제10권3호
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• pp.351-360
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• 1989

This paper describes the design of portable arrhythmia monitor and associated algorithm for automated diagnosis based-on microcomputer in the ambulatory ECG recording, analysis, and transmitting to a hospital host computer immediately through the telephone system. The device differs from Molter recorder in that it does not store normal ECG signals but captures and alarms the ECG during suspected abnormal periods and selected temporal epochs to a central hospital site. This porta file arrhythmia monitor makes use of a general purpose computer and software will be changed to meet the custom requirements of individual physicians and patients. At present it is very obvious that each cardiologist has his own method of analyzing ECG recordings and utilizes past experience more than the firm quantitative analysis of data.

• 한국컴퓨터정보학회논문지
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• 제8권1호
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• pp.97-102
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• 2003

본 논문에서는 기반 통신 인프라를 사용하여, 안정적인 시스템 운영과 상호 운용성 확보, 동시 접속자를 고려하는 컴퓨터 통합형 전화 서비스를 위한 Java기반의 호제어 시스템을 설계하였다. 호제어 시스템의 성능평가는. 사용자가 10명일 때보다는 20명 이상일 때 일정한 응답시간과 시스템의 안정화를 가져왔으며, 100명 이상의 사용자 동시접속 요청에 있어서도 1초 이내에 신속한 응답시간이 이루어져, 모든 플랫폼에서 안정적인 시스템 운영과 상호 운용성 확보는 물론 빠른 접속율과 우수한 성능을 나타내었다.

• 대한간호학회지
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• 제25권4호
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• pp.774-789
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• 1995

Due to the rapid socioeconomic development and the introduction of the national health insurance system the general population's need for health care and utilization of health care services have increased dramatically. As a result of this change. Korea is experiencing a shortage of health care facilities and health manpower, and this leads long wailing line at doctor's offices. One of the solutions of this problem could be home health care system for those who have minor health related problems. With this background, this study was conducted to look at the feasibility of a home-based prenatal care system using information superhighway and nursing informatics specialists. With the home-based prenatal care system, the pregnant woman checks her blood pressure, tests her urine for sugar and protein, and measures her body weight at home and sends the information to a hospital computer via the information networks such as public telephone line and information superhighway. Nursing informatics specialist at the hospital will go through each patient record and screen those who have abnormal values and notify them to see a doctor as soon as possible. Besides telemonitoring features, the proposed system will include tole-education capabilities for the patients so that patient can learn whatever they need to know ragarding the prenatal care via information networks. If this system develops and operates, patient can save time in terms of travel to and from the hospital and waiting time in the hospital. And the health care institute can utilize its resource more efficiently.

• 한국정보통신학회논문지
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• 제6권4호
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• pp.595-603
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• 2002

본 연구에서는 VoiceXML을 이용하여 전화를 통한 대화형 음성인식 항공정보시스템을 개발하였으며 ASP(Active Server Page)모듈을 작성하여 VXML 코딩을 최적화하여 효율성을 증대시켰다. 그리고 GSL(Grammar Specific Language)을 사용하여 사람이 말하는 자연어를 어떻게 하면 컴퓨터가 잘 이해할 수 있게 만들 수 있는지에 연구의 중점을 두었으며 이렇게 설계된 시스템을 실험을 통해 그 효과를 검증해 보았다.

• 한국통신학회논문지
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• 제23권9A호
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• pp.2240-2247
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• 1998

본 논문은 이진 사운딩시퀀스를 이용하여 채널 임펄스응답을 측정하는 새로운 방법에 대하여 기술하였다. 이 새로운 방법은 한개의 상관기를 이용하는 대신에 세 개의 상관기를 이용하나 이상적인 채널 임펄스응답을 얻을 수 있다. 본 세안 방법에서 이용되는 사운딩 시퀀스의 부류는, GSM에 기반을 둔 디지틀 셀루리 이동전화 시스템에서 사용하는 채널 임펄스응답측정 이진부호로서 0 지연과 중간 지연을 제외한 모든 지연에서 자기상관함수 값이 영의 값을 갖는 채널응답측정을 위한 트레이닝 시퀀스이다. 또한 본 논문에서는 0 지연과 중간 지연을 제왼한 모든 지연에서 자기상관함수 값이 영이 되는 이진부호를 탐색하는 효과적인 방법을 제시한다.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제2권1호
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• pp.131-139
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• 1998

With the rapid development of communication technology and widespread uses of internet service, utilization of internet-based medical information systems which transmitts moving pictures of medical objects is becoming a common practice. The internet-based medical information service prvovides richer information than conventional services such as touch-tone telephone, personal computers e-mails, or pagers, because "a picture is worth a thousand words". However, the systems passively transmits moving pictures of the medical objects to the users, and thus the system cannot intelligently adjust itself to provide better service. As the tradeoff exists between transmission speed and quality of the image, there is a need that moving pictures be analyzed to adjust the trnasmission speed and image quality. When very little difference between consecutive images are detected, the system can automatically increase the size of the image files, thus enhancing the quality of image. In contrast, the system should increase the number of images to send more pictorial information by sacrificing the quality of each individual image, when a significant difference is detected. In this paper an adaptive filtering technique is introduced which adjusts the quality of image and transmission speed according to a clinical situation in hospital.