• Journal of Photoscience
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• v.3 no.3
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• pp.147-151
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• 1996

Dynamics of contact ion-pair between 1, 2, 4, 5-tetracyanobenzene anion and cation of biphenyl derivatives was investigated on the picosecond time scale. Solvent effect on the electron transfer was observed and electron transfer rates were examined using Marcus equation which contains distance dependence of the electron transfer rate in the frequency factor, along with the consideration of molecular shape. From the discussion based on disk model for molecular shape, contribution of interring torsional motion of biphenyl to the inner-sphere reorganization energy is strongly suggested, which leads to the physical explanation for the observed solvent effect on the rate of electron transfer.

• Journal of Information Technology Services
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• v.22 no.2
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• pp.93-127
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• 2023

This study analyzed the CEO New Year's addresses of major Korean companies, extracting key topics for employees via text mining techniques. An intended contribution of this study is to assist reporters, analysts, and researchers in gaining a better understanding of the New Year's addresses by elucidating the implicit and implicative features of messages within. To this end, this study collected and analyzed 545 New Year's addresses published between 2012 and 2021 by the top 66 Korean companies in terms of market capitalization. Research methodologies applied include text clustering, word embedding of keywords, frequency analysis, and topic modeling. Our main findings suggest that the messages in the New Year's addresses were categorized into nine topics-organizational culture, global advancement, substantial management, business reorganization, capacity building, market leadership, management innovation, sustainable management, and technology development. Next, this study further analyzed the managerial significance of each topic and discussed their characteristics from the perspectives of time, industry, and corporate groups. Companies were typically found to emphasize sound management, market leadership, and business reorganization during economic downturns while stressing capacity building and organizational culture during market transition periods. Also, companies belonging to corporate groups tended to emphasize founding philosophy and corporate culture.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.8
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• pp.861-877
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• 2012

Recently, the Ministry of Internal Affairs and Communications(MIC) of Japan announced the policies for effective use of spectrum in the 2010s based on the developments of spectrum usage technology, at the same time resolving the social issues in Japan. In Aug. 2010, the establishment of "special white space areas" was suggested to promote the systematization of white space, and a prior model for actualizing the suggestion was published. Also, Action Plan for the frequency reorganization toward building wireless broadband. This paper investigates the future image of the services and systems in the 2010s and surveys the background of the implementing radio wave policy, the major strategy and the policy directions published by MIC of Japan. The contents suggested by this paper contribute to formulating domestic spectrum policies and to promoting the usage and application of spectrum.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1064-1066
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• 2003

In this paper, ground penetrating radar (GPR), which has the capability to detect non metal and plastic mines, is proposed to detect and discriminate antipersonnel (AP) landmines. The time domain GPR - Impulse radar and frequency domain GPR - SFCW (Stepped Frequency Continuous Wave) radar is utilized for metal and non-metal landmine detection and its performance is investigated. Since signal processing is vital for target reorganization and clutter rejection, we implemented the MUSIC (Multiple Signal Classification) algorithm for the signal processing of SFCW radar data and SAR (Synthetic Aperture Radar) processing method for the signal processing of Impulse radar data.

• Journal of Korean Neurosurgical Society
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• v.47 no.1
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• pp.17-25
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• 2010

Objective: The focus of this study is brain plasticity associated with semantic aspects of language function in patients with medial temporal lobe epilepsy (mTLE) Methods: Using longitudinal functional magnetic resonance imaging (fMRI), patterns of brain activation were observed in twelve left and seven right unilateral mTLE patients during a word-generation task relative to a pseudo-word reading task before and after anterior temporal section surgery. Results: No differences were observed in precentral activations in patients relative to normal controls (n = 12), and surgery did not alter the phonological-associated activations. The two mTLE patient groups showed left inferior prefrontal activations associated with semantic processing (word-generation>pseudo-word reading), as did control subjects. The amount of semantic-associated activation in the left inferior prefrontal region was negatively correlated with epilepsy duration in both patient groups. Following temporal resection, semantic-specific activations in inferior prefrontal region became more bilateral in left mTLE patients, but more left-lateralized in right mTLE patients. The longer the duration of epilepsy in the patients, the larger the increase in the left inferior prefrontal semantic-associated activation after surgery in both patient groups. Semantic activation of the intact hippocampus, which had been negatively correlated with seizure frequency, normalized after the epileptic side was removed. Conclusion: These results indicate alternation of semantic language network related to recruitment of left inferior prefrontal cortex and functional recovery of the hippocampus contralateral to the epileptogenic side, suggesting an intra- and inter-hemispheric reorganization following surgery.

• The Journal of Information Technology
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• v.3 no.2
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• pp.63-72
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• 2000

The peformance and quality of Web sites are often being estimated by the frequency that the users approach its site. This paper suggest how a link-editing method can automatically fix a poor organization by calculating each page's relative popularity, and how improve fix poor pages. Page's relative popularity depended on only cases where the objective Is to make it easier for a user to find the requested data; the faster the access, the better the organization of the Web sites according to tree depth.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.2971-2982
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• 2012

This study aimed at analyzing teachers' perception of democratic civic education. A total of 200 childcare teachers participated in the survey, and frequency analysis and cross-tabulation analysis were performed to analyze the survey data. According to the results of the study, first, the childcare teachers were significantly different in the teachers' factors on necessity and difficulty of democratic civic education. The childcare teachers perceived the necessity of democratic civic education, and attributed the cause of the difficulties in democratic civic education to parents' attitudes. Second, there weren't significant differences in the teacher's factors on the content and methods of democratic civic education. Therefore, in this study, it is emphasized that democratic civic education is related to young children's homes and communities, and reorganization of democratic civic education programs based on development of young children is suggested.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.933-940
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• 2012

Recently, it has been shown that quantum coherence appears in energy transfers of various photosynthetic lightharvesting complexes at from cryogenic to even room temperatures. Because the photosynthetic systems are inherently complex, these findings have subsequently interested many researchers in the field of both experiment and theory. From the theoretical part, simplified dynamics or semiclassical approaches have been widely used. In these approaches, the quantum-classical Liouville equation (QCLE) is the fundamental starting point. Toward the semiclassical scheme, approximations are needed to simplify the equations of motion of various degrees of freedom. Here, we have adopted the Poisson bracket mapping equation (PBME) as an approximate form of QCLE and applied it to find the time evolution of the excitation in a photosynthetic complex from marine algae. The benefit of using PBME is its similarity to conventional Hamiltonian dynamics. Through this, we confirmed the coherent population transfer behaviors in short time domain as previously reported with a more accurate but more time-consuming iterative linearized density matrix approach. However, we find that the site populations do not behave according to the Boltzmann law in the long time limit. We also test the effect of adding spurious high frequency vibrations to the spectral density of the bath, and find that their existence does not alter the dynamics to any significant extent as long as the associated reorganization energy is changed not too drastically. This suggests that adopting classical trajectory based ensembles in semiclassical simulations should not influence the coherence dynamics in any practical manner, even though the classical trajectories often yield spurious high frequency vibrational features in the spectral density.

• Journal of Korea Multimedia Society
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• v.10 no.1
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• pp.66-73
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• 2007

SDR technology is a fundamental wireless access technology that combines and accommodates multiple wireless communication standards in one transceiver system through just modifying software using modular communication platforms without any hardware modifications for RF and IF signal processing on the basis of high performance DSP devices. Various communication systems that are designed under diverse and complex network environments require the communication platforms on the basis of SDR supporting reorganization to guarantee simple and fast communication interfaces among the respective wireless networks. This paper introduces a main idea on the implementation of platform on the basis of SDR and a communication platform is designed for experiments that is composed of a DSP board with TMS320C6713 CPU, a FPGA board processing IF signals, and a module with RF transceiver processing wireless LAN frequency bandwidth. Various modulation schemes(BPSK, QPSK, and 16QAM) used in communication systems are applied and tested on the designed platform and the test results shows that it is possible to design a reconfigurable communication terminal platform.

• The Journal of the Korea Contents Association
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• v.17 no.4
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• pp.331-341
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• 2017

This paper aims to analyze English vocabulary of the North Korean textbooks diachronically using the constructed English textbook corpus. The North Korea English textbooks attained from Information Center on North Korea of the Ministry of Unification are divided into before and after Kim Jong-Il era for the year of 1996 in which the curriculum revision has been conducted. They are stored as text files to analyse vocabularies using WordSmith Tools 7.0. The vocabulary size of the revised textbooks increased after the curriculum reorganization, but the number of vocabulary types and vocabulary diversity decreased. After the curriculum revision, it was found that lots of vocabulary related to the establishment of the Kim Jong-Il system appeared as the keyword. It was also found that some vocabularies reflected the economic and social life of North Korea. In addition, through comparison of the 100 high-frequency word list and keywords, it can be concluded that the vocabulary of the English textbooks of North Korea is gradually changing into communicative contents from contents related with written language.