• Journal of Broadcast Engineering
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• v.13 no.4
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• pp.479-487
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• 2008

The method to determine allowable interference criteria is required due to new digital FWSs(Fixed Wireless Systems) adding to allowable frequency bands, besides current FWSs and digital FWSs. In this paper, we suggested a method to define allowable interference between digital FWSs. Types of interference for FWS were defined and channel characteristics were analyzed. Allowable interference criteria were analyzed using the suggested method for M-ary QAM modulations, which is typical modulation technique of digital FWS.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.4
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• pp.434-441
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• 2014

Recently, a mutual interference threat has been increasing among the radar systems due to the rapid growth of the military radar operation. In this paper, the radar interference protection criteria is presented for interoperability in terms of the radar coverage and target detection probability in association with the international recommendation on the interference spectrum by ITU-R. The required criteria for the minimum allowable interference is also presented in terms of INR. In order to ensure the maximum detection probability of the radar under the mutual interference situation, only 5 % of detection range loss is allowed for the case of INR of -6 dB, and required SNR is presented at each INR in terms of the detection range and detection probability. This result will be useful for establishing the interference protection criteria in the combined military radar systems.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.841-847
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• 2018

Since global energy consumption and demand for energy have dramatically risen, a focus on environmental problems and sustainability has become more important. Clean and renewable energy sources such as offshore wind power generation have received attention among new renewable energy options as alternative energy resources. Due to maintenance and operational perspectives, offshore wind farms have been planned for installation in many coastal waters. However, development of offshore wind farms faces interference from existing maritime traffic along the planned areas. In order to safely and effectively govern marine traffic in the vicinity of wind farms and inner areas, standard criteria are suggested to allow vessels to sail the internal waters of offshore wind farm areas. Therefore, the purpose of this study is to establish allowable criteria for sailing vessels and safety zones for offshore wind farms by investigating the local regulations of various offshore wind farm cases overseas. The commended inner safety zone of wind farms is proposed to be a distance of 150 % of the rotation diameter of the wind turbine rotor and a distance of 200 m from the outer wind turbine for the outer safety zone. Besides this, the allowable criteria for sailing vessels within a wind farm is proposed to have an air draft of 14.47 m south-west wind farm sea areas for a minimum margin to avoid hull contact through evaluation of the tide and height of a wind turbine. further studies will be needed to establish vessel sailing criteria among adjacent offshore wind farms as well as vessel sailing criteria within a single offshore wind farm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.3A
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• pp.296-301
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• 2011

GPS(Global Positioning System) service is more important than other wireless services. The GPS is necessary protected from any other interference signals. Therefore, GPS protection ratio was calculated on the basis of bit error rate(BER) in this paper. Simulation results show that the allowable maximum interference power is -190 dBm/Hz and the ratio of interference to noise(I/N) is -16 dB. The achieved protection ratio is available to be applied as the protection criteria of GPS in considering the implementation margin of 4 dB. As a result, the proposed protection ratio of GPS is expected to give standard for a stable GPS service.

• Transactions of the Korean Society of Mechanical Engineers
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• v.5 no.4
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• pp.362-367
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• 1981

Two categories in the design of thick cylinders are suggested and their computer programs are developed; the one termed processing design to ensure the precise inner radius of the cylinder and the other, termd stress compensation design to reduce peak stresses in the cylinder wall. The processing design seeks suitable interference by the method of linear iteration to determine either the radius of the mandrel R or the inner radius ofthe chlinder R$\sub$1/. On the other hand, the stress compensation design seeks first the suitable m and which satisfies the design criteria .sigma.$\sub$actual/ < .sigma.$\sub$allowable/ and then tries to find the suitable interference for given m and .zeta. The design program developed here may be used either in the office at the planning stage of thick chlinders as machine elements of on the processing line to get precise final dimension of inner radius.

• Journal of Satellite, Information and Communications
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• v.7 no.3
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• pp.1-7
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• 2012

In this paper, we was performed the interference analysis to determine an optimal coexisting criteria for the european digital video broadcasting service (DVB-T2) and the IMT-advanced LTE based TV Band Device (TVBD). The TVBD was equipped with the spectrum cognition method. To this end, we set the various transmission parameters, that includes the emission and blocking mask, antenna height and gain, transmission power and bandwidth, channel model etc. Based on this parameters, we were calculated the allowable transmit power, the number of TVBD and the change in probability of interference for the TVBD user operating in the adjacent channels of the DVB-T2 user. Also this paper presents how many TVBD users can sharing with DVB-T2 for spectral cognition performance.

• Journal of KSNVE
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• v.10 no.2
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• pp.261-268
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• 2000

The instrumented capsule is subjected to flow-induced vibration(FIV) due to the flow of the primary coolant and then the structural integrity of the capsule during irradiation in the HANARO reactor is an issue of major concern. For this purpose the acceleration was measured by four accelerometers attached to the protection tube of the capsule mainbody and the displacement of test holes was calcultated using commercial finite element program ANSYS to evaluate the structural interference with the neighboring flow tubes under the reactor operating condition. The calculated displacements of test holes in the reactor in-core were found to be lower than the values of allowable design criteria.