• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.790-794
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• 2012

A output strength is limited according to the frequency used in order to protect other wireless stations from interference caused by radio waves emitted from the low power wireless installations. For receivers, unwanted spurious emission is regulated, and regulations in Korea define that additional spurious emission for receivers in the low power wireless installations under 1GHz should be -54dBm, but no regulations have been established yet for low power wireless installations over 1GHz. It is presently required to set domestic standards for devices over 1GHz on account of the expansion of the communication market and its service.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.2 s.105
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• pp.198-206
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• 2006

The GFSK Transceiver of 400 MHz ISM band for data communication is designed and fabricated. To reduce the occupied bandwidth of transmitted signal, the GFSK modulation is selected. The measured results of fabricated transceiver show the data rate of 2,400 bps at 8.5 kHz bandwidth, frequency deviation of less than ${\pm}3\;kHz$, sensitivity of -107 dBm at SINAD of 20 dB, BER of less than $1.8{\times}10^{-3}$ at -110 dBm input power. The fabricated transceiver is satisfied with the regulation of radio wave and has the good performance.

• Journal of Advanced Navigation Technology
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• v.6 no.1
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• pp.62-68
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• 2002

Mother ship must be able to know accident occurrence information rapidly to rescue crew who fall in sea. In this paper, designed and manufactured transceiver of prescribed 447 MHz is operating as low power radio station specified in Radio Regulation. So, it is available without special permission proceedings getting form probation so that the use of this system may be easy. the system has been started for operation when the sensor get in touch with water. The system transmits with modulation by 500Hz square wave, and the receiver alarms when the transmitted signal is received. Therefore, the system can be used for not only saving a life, but also for low speed of data transmission below 2,400 bps, and other purposes.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2063-2066
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• 2005

This paper presents an approach to detect the dielectric condition of FRP Hot Stick in EHV high voltage cable whereas shutting down the power system is not necessary. The radio frequency generating method is adopted by transmitting radio wave into the Electrodes. This instrument is small, easy to use and also inexpensive. Furthermore, the impurity level of dirt on high voltage insulator (non-ceramic type) will be analyzed by using the methods based on IEEE Std.978-1984 at 105 kV.DC. /305 mm. and OSHA Regulation 1910.269 Part J - live line tools. The frequency at 10-20 MHz is applied to FRP Hot Stick via Electrode1 and from FRP Hot Stick surface to Electrode 2. After that the results will be evaluated by testing in each condition of FRP Hot Stick, such as dry surface, hot surface, foil winding and conductor inserting. Finally, the watt loss will be examined and compared with the loss from humidity and Carbon tracking. The important components of this system are radio frequency generating unit, frequency stabilizing unit, frequency amplifier, FRP Hot Stick frequency counter, processing unit, and display unit.

• TTA Journal
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• s.42
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• pp.101-113
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• 1995

지난 10월 23일부터 11월 17일까지 스위스 제네바의 ITU 회의장에서 146개 국가와 25개 국제기구에서 약 1300명이 참가한 가운데 세계전파통신 회의(World Radio communication Conference, WRC-95)가 개최되었다. WRC는 1993년 국제전기통신연합(ITU)이 조직을 바꾸면서 종래 WARC(세계 무선 주관청회의, World Administrative Radio Conference)를 계승하며, 한편 기술의 발달에 따른 통신 사업자, 제조업체 등의 민간 부문의 참여를 활성화하는 전파분야의 국제회의이다. 이 회의에서 결정된 사항은 각국이 따르도록 되어있으므로 국제화 시대를 살아가는 지금에 있어서 뿐만 아니라 전파의 국제적 사용이라는 특성을 고려할 때 그 중요성은 굳이 강조하지 않더라도 관계자 모두가 충분히 알고 있을 것이다. 우리나라에서는 박영일 전파방송관리국장을 비롯하여 모두 28명의 대표단이 참가하였으며, 이와 관련하여 1994년부터 2차례 진행되었던 WRC 준비반 회의(Conference Preparatory Meeting, 이하 CPM)에 참가하여 회의 준비를 하였고, 1995년 5월에는 대표단을 구성하여 각국의 제안 내용 검토와 우리의 제안 내용 관철을 위한 대책 등 착실한 준비를 하였고, 이번 회의에 RR 개정에 대한 우리의 의견과 주파수 분배표 수정에 대한 의견 등 모두 43건의 의견을 제안하여 회의에 임하였다. 이번 WRC-95의 주요 내용은 크게 2가지로 구별할 수 있다. 첫 번째는 그동안 전파규칙(Radio Regulation, 이하 RR)의 개정을 위하여 구성되었던 자발적 전문가 그룹(Voluntary Group of Experts)의 보고서를 토대로 기존의 RR을 수정 및 재구성하므로서 RR을 간소화 하기 위한 작업이 진행되었으며, 둘째로 기술의 발달에 따른 이동위성 서비스 등의 새로운 서비스를 도입하기 위한 주파수 분배표의 수정 작업이 진행되었다. 본 고에서는 이동위성 서비스 도입을 위한 이번 WRC-95의 회의 분위기를 전달함으로서 무선통신 관계자들이 WRC의 의미를 다시 한번 생각해 볼 수 있는 기회를 갖고자 한다.

• ETRI Journal
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• v.37 no.6
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• pp.1077-1086
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• 2015

This paper presents a general-purpose design scheme of a filter bank (FB)-based radio frequency (RF) transceiver that operates across the entire ultra-high frequency (UHF) TV band from 470 MHz to 698 MHz and complies with the TV white space (TVWS) regulatory requirements. To this end, an intermediate frequency (IF) band-pass filter (BPF) with a sharp skirt characteristic is considered as a solution for handling the incoming signals from a baseband modem. Specifically, an FB-based BPF structure with four ceramic resonator filters that effectively rejects unwanted signals is proposed to extract a desired signal in the TV band. Achievable data rates of a cognitive radio system (CRS) employing the proposed FB-based RF transceiver at the application layer are investigated in both wired and wireless environments. The service coverage of the CRS network is measured according to several modulation and coding schemes (MCSs) of the CRS. The results show that the coverage of a wireless network in a nearly open area can be extended by more than 9.3 km in the TVWS. Experimental results also confirm that the proposed FB-based RF transceiver is adequate for utilization in TVWS applications.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.3810-3830
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• 2015

In this paper, we investigate the differential game theoretic approach for distributed dynamic cooperative power control in cognitive radio ad hoc networks (CRANETs). First, a payoff function is defined by taking into consideration the tradeoff between the stock of accumulated power interference to the primary networks and the dynamic regulation of the transmit power of secondary users (SUs). Specifically, the payoff function not only reflects the tradeoff between the requirement for quickly finding the stable available spectrum opportunities and the need for better channel conditions, but also reveals the impact of the differentiated types of data traffic on the demand of transmission quality. Then the dynamic power control problem is modeled as a differential game model. Moreover, we convert the differential game model into a dynamic programming problem to obtain a set of optimal strategies of SUs under the condition of the grand coalition. A distributed dynamic cooperative power control algorithm is developed to dynamically adjust the transmit power of SUs under grand coalition. Finally, numerical results are presented to demonstrate the effectiveness of the proposed algorithm for efficient power control in CRANETs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.4 no.1
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• pp.32-37
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• 1979

The corona noise level at the place 10m and the frequency 1MHz from the new 345KV transmission line is 72dB in the maximum rain-fall and 63dB due to the wet conductors. The synthesized corona noise level of all 3 phases dominantly depends on the phase which has maximum corona level among them. The measured characteristic of the variation with distance from the line coincided well with the theoretically calculated value in this paper. The corona noise level was the highest level in rainy weather or snow-fall. It takes a few hours, for the corona noise to be stable after a rain-fall or snow-fall. The measured value of the corona noise level corresponds quite well with the formula for the corona noise level revision. It was necessary to quantize S/N ratio into radio reception quality for the radio interference due to the transmission line. Some regulations for radio reception quality were defined through long term experiments and ratings by ITU, IEEE comittee, NHK in Japan and others. Fixing our own regulation about radio reception quality should be required.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6021-6024
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• 2014

Background: The STK15 gene located on chromosome 20q13.2 encodes a centrosome-associated kinase critical for regulated chromosome segregation and cytokinesis. Recent studies have demonstrated STK15 to be significantly associated with many tumors, with aberrant expression obseved in many human malignancies. The purpose of this study was to investigate expression of STK15 in esophageal squamous cell carcinomas (ESCCs) in a Mongolian population. Methods: Two non-synonymous single nucleotide polymorphisms in the coding region of STK15, rs2273535 (Phe31Ile) and rs1047972 (Val57Ile) were assessed in 380 ESCC patients and 380 healthy controls. We also detected STK15 mRNA expression in 39 esophageal squamous cell carcinomas and corresponding adjacent tissues by real time PCR. Results: rs2273535 showed a significant association with ESCC in our Mongolian population (rs227353, P allele = 0.0447, OR (95%CI) = 1.259 (1.005~1.578)). Real time PCR analysis of ESCC tissues showed that expression of STK15 mRNA in cancer tissues was higher than in normal tissues (p = 0.013). Conclusions: Our study showed that functional SNPs in the STK15 gene are associated with ESCC in a Mongolian population and up-regulation of STK15 mRNAoccurs in ESCC tumors compared adjacent normal tissues. STK15 may thus have an important role in the prognosis of ESCC and be a potential therapeutic target.

• Electronics and Telecommunications Trends
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• v.15 no.2 s.62
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• pp.66-72
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• 2000

기술기준은 전파 이용질서를 확립하여 공공의 이익을 추구하는 데 목적이 있다. 본 고에서는 국가간의 상호인정(MRA) 추진으로 각국의 기술기준을 상호조화 시키는 세계적인 추세에 대응하기 위하여 국내 정보통신 기술기준에 대한 전반적인 재검토를 통하여 기술기준을 이용자 편익 및 권익을 보호할 수 있는 무선설비규칙의 개선 방향에 대하여 논의하고자 한다. 이러한 체계 개선을 통하여 국가의 경쟁력을 강화하고 향후 국제 통신시장에 국제적인 신뢰도를 높이는 데 기여할 수 있을 것이다.