• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.7 s.98
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• pp.709-719
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• 2005

The forward link of the 3 G CDMA system may become limited under the increasing of the number of users. The conventional channelization code, Walsh code, has not enough sizes for much possible non, therefore, the quasi orthogonal function(QOF), which process optimal cross-correlation with Walsh code, is considered. In this paper, we investigate quasi orthogonal function on Jacket matrices, which can lead lower correlations values and better performance in 3 G CDMA system. Moreover, to simple the detector and improve the BER performance, a novel detection for QOF CDMA system is proposed. Finally, the simple recursive generation of the bent sequences for QOF mask function is discussed.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.121-129
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• 2010

We evaluated microbial populations and aflatoxin production in unhulled and white rice from rice processing complexes of the National Agricultural Cooperative Federation in five regions in Korea and identified three predominant Aspergillus species. Fungal and bacterial populations in rice samples were significantly different between regions in 2007. Aflatoxins were also detected and varied at the levels of 2.45 - 3.43 ng per g unhulled rice grain and 1.29 - 2.09 ng per g white rice grain. Unhulled rice generally detected higher level of aflatoxins than white rice regardless of sampling regions; however, no significant differences were found in Anseong and Cheonan in 2005 and Cheonan and Gimpo in 2007. Aflatoxin production between sampling regions was not different regardless of rice type and sampling year. Although the fungal diversity was highly distinct from region to region, three Aspergillus isolates were predominant in the rice samples; thus, representative isolates AC317, AF57, and AF8 were selected and identified based on their morphological and molecular characteristics. Consequently, isolates AC317, AF57, and AF8 were identified as A. candidus, A. flavus, and A. fumigatus, respectively. These fungi can produce mycotoxins that are harmful for consumers and thus it is important to detect and reduce the population of storage fungi in rice.

• Journal of Korean Library and Information Science Society
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• v.42 no.4
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• pp.203-221
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• 2011

This study attempts to investigate the current stage of collection development process in small libraries through case study to eleven small libraries in Yeongnam region. Library collection is the primary element of a library and collection development is the starting point of librarians' duty. The researcher recognized the problems observed in collection development process in the case small libraries and discovered the widespread obstacles restraining the future development. Through the visits and observations, aging book collections, lack of diversity in the form of materials acquired, imbalance in subject distribution, and the imbalance in circulation are identified. Suggestions are to be added: collection development duty can not be fulfilled without proper support by local governments. While small libraries penetrate into peoples' territory, Public libraries should seek to enhance and improve their service orientation as well as a cooperative network with these small libraries.

• Korean journal of communication and information
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• v.34
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• pp.275-305
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• 2006

The main research question of this paper is as follows: How can broadcasting both cause the crisis in democratic participation and yet also offer the solution? The contradiction in broadcast localism has never been adequately resolved in spite of regulation at all in practice, in that localism simply cannot account for the diversity of modern life and for the external forces that incorporate local communities into much larger economic and communications network. The concept of locality in local television, however, has been multiplied and enlarged in order to adjust to "time-space compression". Recently the local television have been "interface" combining and negotiating the globalization of media market and the decentralization of political power, the economies of scale and the activation of local democracy, consequently aiming at the horizontal-cooperative network instead of old vertical-dependent one.

• Spatial Information Research
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• v.23 no.4
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• pp.33-46
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• 2015

The fact that the limits of information recency, diversity, and usability are mainly caused by the supply oriented geospatial data and service development is commonly recognized. It is recently tried to overcome the limits by facilitating user experience and VGI(Volunteered Geographic Information) in several geospatial web services. This study suggests conceptual architecture and service scenario for geospatial collaborative platform prototype through review and examination of previous researches. The prototype, composed of 4 unit modules: 3D POI Creation Module, 3D POI Application Module, 3D POI/Event Management Module, 3D POI/Event Monitoring Module, provides the capability of collaboratively dealing with geospatial work. The suggested service scenario is demonstrated by developing prototype for the service modules.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.11
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• pp.5343-5364
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• 2016

Considering the tradeoff between energy consumption and outage behavior in buffer-aided relay selection, a novel energy-efficient buffer-aided optimal relay selection scheme with power adaptation and Inter-Relay Interference (IRI) cancellation is proposed. In the proposed scheme, energy consumption minimization is the objective with the consideration of relay buffer state, outage probability and relay power control, in order to eliminate IRI. The proposed scheme selects a pair of optimal relays from multiple candidate relays, denoted as optimal receive relay and optimal transmit relay respectively. Source-relay and relay-destination communications can be performed within a time-slot, which performs as Full-Duplex (FD) relaying. Markov chain model is applied to analyze the evolution of relay buffer states. System steady state outage probability and achievable diversity order are derived respectively. In addition, packet transmission delay and power reduction performance are investigated with a specific analysis. Numerical results show that the proposed scheme outperforms other relay selection schemes in terms of outage behavior with power adaptation and IRI cancellation in the same relay number and buffer size scenario. Compared with Buffer State relay selection method, the proposed scheme reduces transmission delay significantly with the same amount of relays. Average transmit power reduction can be implemented to relays with the increasing of relay number and buffer size, which realizes the tradeoff between energy-efficiency, outage behavior and delay performance in green cooperative communications.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.6
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• pp.648-653
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• 2011

In this paper, coordinated space division multiple access(SDMA) technology is proposed to mitigate inter-cell interference by using partial channel state information in cooperative wireless communications system with limited feedback. Each AT selects an optimal cluster transmission mode and sends it back to a cluster scheduler, and at the cluster scheduler, ATs are scheduled within a AT group with the identical cluster transmission mode, and the optimal transmission mode and the corresponding scheduled ATs are determined to maximize scheduling priority. Also, in order to enhance multiuser diversity gain, an extended transmission feedback method is proposed to feed back multiple preferred cluster transmission modes at each AT. It is shown that the proposed coordinated SDMA scheme outperforms existing non-coordinated SDMA schemes in terms of the average system throughput.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.1
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• pp.110-122
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• 2020

Many companies make considerable efforts in implementing supply chain management systems to increase their competitiveness. In particular, there are significant investments in their ICT (Information and Communication Technology) and supply chain. However, considerable diversity exists in how well firms have been able to assimilate ICT and leverage the business value of it. In addition, studies on supply chains, particularly Real Time Enterprise (RTE) competence, which is cited for rapid information sharing and dynamic capabilities for each role in the supply chain, are insufficient. The purpose of this paper is to explore and evaluate effect of ICT utilization capabilities, including 'ICT internal cooperative capabilities' and 'ICT operational flexibility capabilities', on RTE capabilities (flexibility, visibility and prediction) and supply chain performance. To validate the research model proposed in the study, survey was conducted on companies using ICT along the supply chain of manufacturing industries. 216 data were used, SPSS and AMOS were used for the analysis methods. Study results showed that ICT internal collaboration capabilities affect agility, one of RTE capabilities, but not visibility and prediction, and ICT operational flexibility capabilities have affected all three RTE capacities. And, RTE capabilities had a huge impact on supply chain performance as expected. In this paper, it has been found that the ICT capabilities in manufacturing are an important factor in improving RTE capabilities that are important in the supply chain and improving the performance of the supply chain.

• The Korean Journal of Community Living Science
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• v.16 no.2
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• pp.61-73
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• 2005

This study aims to examine the socio-demographic heterogeneity of community participation in rural Korea. Data was collected through interviews with 1,870 rural householders and housewives who have lived in Up or Myen as an administrative unit of rural communities, and analyzed by the SPSS/PC Win V.10 program. The statistical techniques used for this study were frequency and percentile. The major findings of this study were as follows. Firstly, the extent to which rural people have participated in community organizations were: cooperative groups, $80.8\%$; religious groups, $20.6\%$; learning groups, $12.7\%$; political groups, $9.8\%;$ civil groups $6.7\%$; and voluntary groups, $5.3\%$. Whereas the numbers were high for community participation in groups related to agricultural production, participation in civil and voluntary groups were lower. Secondly, it showed that people who lived in urbanized and high population density areas were more likely to participate in community groups. The diversity of community organizations was different according to the level of rurality. Thirdly, farm householders were more likely to participate in religious, civil and voluntary groups than non-farm householders. Fourthly, people with higher education, females, those in the 40 to 50 age groups were more likely to participate in community organizations. Fifthly, even though men are more likely to participate in political parties, women were more likely then men to agree that women should participate in political parties. This empirical study could support the results of Sundeen (1988) and Wilson and Musick (1997) in that education was related positively to community participation. In addition, we concluded that community participation in a rural development process has two main considerations: philosophical and pragmatic. This implies that there is room for government to enable and facilitate 'true' community participation. That can be done through policy reform which creates a permissive environment for community decision-making and input, in addition to simply supporting community development through financial assistance.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.6
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• pp.70-80
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• 2012

In this paper, we consider the amplify-and-forward relaying systems with the relay selection (AF-RS) using full channel information (FCI) and using partial channel information (PCI), respectively, in which the direct communication link between a source and a destination is available. And, the outage probabilities for the AF-RS using FCI and using PCI are investigated in Rayleigh fading channels, respectively. We provide exact outage probabilities, tight outage probability lower bounds, and asymptotic outage probabilities, respectively. And also, we present coding gains achievable by the AF-RS using FCI and using PCI. Through numerical investigation, all the analytic expressions are verified, and the coding gains are respectively evaluated with different average channel powers for the first and the second hop as well as different numbers of relays.