• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.5
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• pp.2047-2066
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• 2016

In this paper, we investigate joint power allocation and relay selection (PARS) schemes in non-orthogonal cooperative protocol (NOCP) based cognitive relay networks. Generally, NOCP outperforms the orthogonal cooperative protocol (OCP), since it can provide more transmit diversity. However, most existing PARS schemes in cognitive relay networks focus on OCP, which are not suitable for NOCP. In the context of NOCP, we first derive the joint constraints of transmit power limit for secondary user (SU) and interference constraint for primary user (PU). Then we formulate optimization problems under the aforementioned constraints to maximize the capacity of SU in amplify-and-forward (AF) and decode-and-forward (DF) modes, respectively. Correspondingly, we derive the closed form solutions with respect to different parameters. Numerical results are provided to verify the performance improvement of the proposed PARS schemes.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2177-2182
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• 2016

Using the existing exact but quite complicated symbol error rate (SER) expressions for M-ary phase shift keying (M-PSK) and M-ary differential phase shift keying (M-DPSK), we derive effective and concise closed-form asymptotic SER formulas especially in Rician-Nakagami fading channels. The derived formulas can be utilized to efficiently verify the achievable error rate performances of M-PSK and M-DPSK systems for the Rician-Nakagami fading environments. In addition, by exploiting the modulation gains directly obtained from the asymptotic SER formulas, we also theoretically demonstrate that M-DPSK suffers an asymptotic SER performance loss of 3.01dB with respect to M-PSK for a given M in Rician-Nakagami fading channels at high signal-to-noise ratio (SNR).

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.5
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• pp.295-304
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• 2003

In this paper, we proposed a hardware-oriented Genetic Algorithm Processor(GAP) based on subpopulation architecture for high-performance convergence and reducing computation time. The proposed architecture was applied to enhancing population diversity for correspondence to premature convergence. In addition, the crossover operator selection and linear ranking subpop selection were newly employed for efficient exploration. As stochastic search space selection through linear ranking and suitable genetic operator selection with respect to the convergence state of each subpopulation was used, the elapsed time of searching optimal solution was shortened. In the experiments, the computation speed was increased by over $10\%$ compared to survival-based GA and Modified-tournament GA. Especially, increased by over $20\%$ in the multi-modal function. The proposed Subpop GA processor was implemented on FPGA device APEX EP20K600EBC652-3 of AGENT 2000 design kit.

• Journal of the Korean Operations Research and Management Science Society
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• v.37 no.2
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• pp.113-125
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• 2012

The logistic model and the Bass model have diverse names and formulae in diffusion theory. This diversity makes users or readers confused while it also contributes to the flexibility of modeling. The method of handling the integration constant, which is generated in process of deriving the closed form solution of the differential equation for a diffusion model, results in two different 'actual' models. We rename the actual four models and propose the usage of the models with respect to the purpose of model applications. The application purpose would be the explanation of historical diffusion pattern or the forecasting of future demand. Empirical validation with 86 historical diffusion data shows that misuse of the models can draw improper conclusions for the explanation of historical diffusion pattern.

• Journal of Environmental Science International
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• v.29 no.9
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• pp.935-938
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• 2020

This study investigated the oviposition characteristics of Protaetia brevitarsis seulensis after emergence as adults from the larva collected from three regions in Gangwon-do, Chungcheongnam-do, and Jeju-do. The laying egg method was identified with zone breeding, and the average and cumulative number of eggs laid were measured once a week for seven weeks. The average number of eggs laid peaked until 4 weeks, and subsequently decreased. The source areas with respect to average number and cumulative number of eggs laid were in the order of Jeju > Chungnam > Gangwon. In conclusion, this result suggests a method for continuously improving management and economic feasibility of insect farming by securing genetic diversity, and raising the most productive breeds to select individuals form regions associated with high numbers of laid eggs.

• Journal of the Korean housing association
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• v.15 no.2
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• pp.35-42
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• 2004

This study is to investigate the various concepts of ecology for developing the perspectives and approaching guidelines to the ecological building design. The concepts of ecology may be some background to the environmental issues within architecture. While there are many words which mean environmentally-friendly architecture, ecological building design to which I refer here is the ecocentric and holistic design rather than the anthropocentric and mechanical one. Ecological and social systems are open, interacting, and unpredictable. So we should leave room within our planning of architectural project and in construction of new housing development for nature's unpredictable events. The approach to ecological building design might be the holistic perspectives, the respect of place and participation of people, to admit the complexity and diversity. The world in which we are living is highly unstable.

• Journal of Information Science Theory and Practice
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• v.9 no.3
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• pp.1-13
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• 2021

In the current smart device-based information environment, information utilization is closely related to social capital. Additionally, the smart divide that occurs owing to the differences in use of smart devices has a significant influence on social capital. In this respect, this research empirically analyzed how the smart divide affects social capital construction. The study found that the level of and proficiency in using smart devices and diversity of the information formats used through smart devices affect social capital construction. Further, people who fully utilize smart devices can enhance their participation in social activities, social networks, and reciprocal activities, leading people to construct social capital in a wider range. Contrarily, those who are unable to use smart devices adequately may be disadvantaged in terms of the opportunity to construct social capital and share public interests. Thus, to maximize the intrinsic value of social capital, it is necessary to consider the factors of the smart divide as a complicated and multi-faceted digital divide and the ways to utilize social capital as a driving force for integrating society, and not as a mechanism for dividing members of society.

• Journal of the Daesoon Academy of Sciences
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• v.25_2
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• pp.137-176
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• 2015

This study intends to focus on feasible measures to take advantage of pilgrimage to inspire adherents of The Fellowship of Daesoonjinri with the ideology of Daesoon and to overhaul existing missionary work. This study addresses preceding researches with regard to pilgrimage as theoretical grounds to review what pilgrimage has been meant to be. Also, this study conducts the survey on the motif and preference of pilgrimage that are expected to affect pilgrim behaviors, and it includes the satisfaction with the pilgrimage as a parametric effect. The survey and analysis results say that the motif and preference of the pilgrimage are the leading variables that significantly correlate to the pilgrimage satisfaction. In addition, the pilgrimage satisfaction is not only a key factor that affects pilgrim behaviors but a parametric effect that strongly relates to the motif and preference of the pilgrimage. Conducted based on empirical analysis, this study offers a diversity of approaches to tourism program development with respect to pilgrimage: customized pilgrimage programs, unique storytelling about the holy places, content development with a range of topics and difficult levels, and evaluation and feedback systems for pilgrimage programs

• Journal of the Korean Institute of Intelligent Systems
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• v.12 no.4
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• pp.317-322
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• 2002

The major operations of Evolutionary Computation include crossover, mutation, competition and selection. Although selection does not create new individuals like crossover or mutation, a poor selection mechanism may lead to problems such as taking a long time to reach an optimal solution or even not finding it at all. In view of this, this paper proposes a hybrid Evolutionary Programming (EP) algorithm that exhibits a strong capability to move toward the global optimum even when stuck at a local minimum using a synergistic combination of the following three basic ideas. First, a "local selection" technique is used in conjunction with the normal tournament selection to help escape from a local minimum. Second, the mutation step has been improved with respect to the Fast Evolutionary Programming technique previously developed in our research group. Finally, the crossover and mutation operations of the Genetic Algorithm have been added as a parallel independent branch of the search operation of an EP to enhance search diversity.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.4
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• pp.24-31
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• 1995

In this paper, the dual-mode burst-error-correcting decoding algorithm is adapted to the multiple trellis-coded .pi./4 shift QPSK in order to achieve the improvement of bit error rate (BER) performance over fading channels. The dual-mode adaptive decoder which combines maximum likelihood decoding with a burst detection scheme usually operates as a Viterbi decoder and switches to time diversity error recovery whenever an uncorrectable error pattern is identified. Rayleigh fading channels and Rician fading channels having the Rician parameter K=5dB are used in computer simulation, and the simulation results are compared with those of interleaving techniques. It is shown that under the constraint of the fixed overall memory quantity, the dual-mode adaptive decoding scheme gains an advantage in the BER performance with respect to interleaving strategies.