• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.4
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• pp.302-307
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• 2001

The underwater background noise measured in Geoje and Tongyoung diving fishing ground from May to December, 2000 and analyzed to get optimum carrier frequency and transmitter power level for underwater wireless telephone design. The results obtained are summarized as follows: 1. At the Geoje and Tongyoung diving fishing ground, the lowest ambient noise band was 25~30kHz with 57dB and 52dB re 1$\mu$Pa, respectively. 2. At the Geoje and Tongyoung diving fishing ground, the lowest noise band during fishing activity was 67dB and 62dB re 1$\mu$Pa, respectively. 3. At the Geoje diving fishing ground, the noise of water jetter which is a digging machine for subbottom shells was 102dB re 1$\mu$Pa. 4. Considering the design parameters of underwater wireless telephone, it is found that the optimum carrier frequency band is around 30kHz and the transmitter source level should be at least 131dB re 1$\mu$Pa for 500m range telephone.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.439-443
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• 2008

Painting process or coating with acrylic film may improve the surface defects of injection molded parts deteriorated by weldlines. flow marks. and etc. However such processes increase the production costs and increase environmental problems. Recently various types of rapid mold heating & cooling technology have been developed in order to improve surface quality of products. In this study. the heating & cooling performance of a telephone case mold is investigated by heat transfer analysis, in which the rapid mold heating & reeling technology is applied. The surface temperature of the mold was measured using thermal image camera and compared with analysis results. The influence of the rapid mold heating & cooling technology on weldline appearance and cycle time increase was also examined.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.2
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• pp.18-26
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• 1985

최근에 들어 환경보전에 대한 시민의식이 고조되고 깨끗한 자연 및 생활환경을 유지하려는 노력 이 각계에서 일고 있다. 이와 관련된 문제점의 하나가 대기오염이며 이 오염원 중의 하나가 자 동차 배기물로서 특히 탄화수소(hydrocarbon:HC), 일산화탄소(CO), 질소산화물(NO$_{x}$)에 의 한 대기오염의 심각히 대두되어 왔으며 현재 환경청 등에 의해 국가적 차원에서 자동차 배기물에 대한 규젤ㄹ 강화하려는 움직임을 보이고 있다. 미국의 경우 연도별 배기규제기준을 살펴 보면 표.1 과 같으며, 국내에서도 88년까지 미국, 일본수준으로 신규제작차의 배출혀용기준을 강화할 계획으로 있다. 표1의 규제치르 보면 60년대의 비규제기간중의 배출량에 비해 탄화수소의 경우 96%, CO는 96%, NO$_{x}$는 76%의 감소를 보여주고 있으며 이 규제치는 5만mile을 규정된 방법으로 주행한 후 복잡한 사이클과정의 연방정부 시험절차 (Federal Test Procedure, FTP 또는 Constant Volume Sampling-Cold and Hot, CVS-CH)를 거쳐 만족하여야 한다. 상기의 규제치들을 만족시키기 위한 실용적 방법으로서 촉매전환기(catalytic converter)가 채택되고 있 으며 따라 본 해설에서는 자동차용 촉매전화기에 대한 자료들을 정리하여 특성, 문제점 등을 살펴 보고자 한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.7B
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• pp.464-468
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• 2005

The DVR industry has been grown with their own, proprietary systems without the need of standards because the security products are independently installed in small scale and the communication needs are very limited. The industry might have tighter security than having standardized products, but the appearance of IP surveillance and the need of communications with IP products such as IP Phones and IP-PBX made the standardization unavoidable. In this paper, we built an IP surveillance system with SIP based session control and investigated the applications of it other than the security itself.

• Broadcasting and Media Magazine
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• v.13 no.4
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• pp.65-79
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• 2008

최근 TV 디지털 방송에 대한 많은 관심이 집중되면서 국내의 디지털 텔레비전 방송(Digital Multimedia Broadcasting: DMB)과 유럽의 디지털 텔레비전 방송((Digital Video Broadcasting: DVB)에 대한 기술 개발이 지속적으로 이루어지고 있다. 국내의 DMB는 지상파 DMB와 위성 DMB가 있고, 유럽의 DVB는 일반 방송국으로부터 가정용 또는 사무실용의 고정된 장치에서 수신을 하는 DVB-T와, 휴대 전화기나 휴대용 영상기기 등의 저전력, 이동성, 휴대성을 고려한 DVB-H가 있다. 또한 휴대폰이나 PDA와 같은 휴대 통신단말기의 기능복합화 요구에 따라, 국내에서는 휴대폰에 TV 방송기능과 인터넷을 이용할 수 있는 네트워크 서비스가 내장된 단말기가 속속 출시되어 치열한 경쟁구도에 접어들고 있다. 이러한 시장요구에 부응하기 위해 다양한 분야에서 기능 복합화를 실현하고자 하는 " Ubiquitous Convergence화"가 급속도로 진행되고 있다. 그러나 단일 시스템에서 2가지 이상의 기능(GSM/GPRS & DVB-H)이 Convergence화 되어있을 경우, 시스템 상호간 간섭영향으로 각 장치의 기능 저하가 발생하고 있다. 특히, 동일 주파수대역 사용에 의해 방생하는 간섭영향에 대한 적절한 대응이 요구되는 시점이다. 본 고에서는 무선 통신 분야 기술개발의 한 부분으로 부품의 초소형화 및 동일 주파수대역 사용에 의해 발생하는 간섭영향을 제거하는 내용에 대해서 기술한다.

• Journal of Korean Society for Quality Management
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• v.33 no.4
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• pp.103-110
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• 2005

Advanced function has been considered to be the most important aspect of the cellular phone. However, leading companies are now implementing the fashion branding strategy which stresses both high technology and appealing design. By means of the conjoint analysis, this research focuses on identifying the preferred design profile related to style of the key cover, color and texture of the case, and presence or absence of the noctilucent material coated on the part of surface. We also evaluate the relative importance of factors to determine the design concept of new cellular phone. Results indicate that consumers most prefer the silver-colored, sliding key cover phone with soft and noctilucent surface.

• The Korean Journal of Mycology
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• v.9 no.3
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• pp.147-151
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• 1981

During the period of June 15, 1978 to February 28, 1979 fungi were isolated from 101 public and home telephones in 6 different cities and classified. Total 203 isolates were obtained and classified into 8 genera and 6 species, however 44 of the isolates were unidentified. Penicillium spp. were frequently found. Forty isolates were derivated from coffee shops, 51 from street public telephones, 35 from stores, 26 from offices and 19 from homes. Also 27 were from Seoul, 30 from Daegu, 46 from Gunsan, 82 from Chunju and 18 from Jaeju. Twenty-seven were isolated in summer and 174 in winter. From the above observations, it is concluded that the transimitters are heavily colonized with various species of fungi and some of them are pathogens. The rates of colonization appeared to be various by locations and seasons.

• Proceedings of the KIEE Conference
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• 2006.10d
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• pp.107-109
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• 2006

This paper presents the design and fabrication results of a voice coil type actuator for auto focusing(AF) functional module of mobile phone cameras. Axisymmetric FEM and 3-dimensional FEM is used to analyze and design the actuator, and the performance is verified by fabrication and evaluation of it. The size of the fabricated 2M pixel AF module is $10.5{\times}10.5{\times}7.9mm$, and the operating performance was satisfactory.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.89-92
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• 2004

전화 음성용 화자인증 시스템 전화기에서 의뢰인의 ID와 음성을 입력받은 후 인증관련 처리론 PC에서 수행하여 그 인증 결과를 의뢰인의 전화로 알려주는 시스템으로 본 논문에서는 CTI(Computer Telephony Integration) 기술이 적용된 Dialog/4 보드를 이용하여 시스템을 구현하였다. Dialog/4 보드를 통하여 시스템에 입력된 ID와 음성에 대하여 신호처리와 특징 추출을 거친후 ID에 해당하는 화자모델과 배경화자 정보를 이용하여 유사도를 계산하여 의뢰인에 대한 인증 또는 거절의 결과를 알려준다. 실제의 전화음성을 이용한 화자인증 시스템이 성능평가에서 전화음성으로 실험을 할 경우 $99.6\%$의 인증률을 보여주었다.

• Journal of the Korea Computer Industry Society
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• v.5 no.4
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• pp.443-452
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• 2004

In this paper, suggests voice newspaper retrieval system in which newspaper companies classify the news fields into politics, society, economy, IT, international issue, culture, life, information and etc title by title and summarize them to provide wire or wireless newsretrieval service on the phone through design and realization of voice interface by using VoiceXML associated technology useful to design an application that makes it possible to communicate with computer like communicate with person without mouse or keyboard used, so that busy or blind people can receive news service more easily.