• ETRI Journal
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• v.43 no.2
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• pp.232-245
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• 2021

As wireless communication continues to develop in limited frequency resource environments, it is becoming important to identify the state of spectrum utilization and predict the amount needed in future. It is essential to collect reliable information for data analysis. This paper introduces a platform that enables the gathering of the scheduling information of a long-term evolution (LTE) cellular system without connecting to the network. A typical LTE terminal can confirm its assigned resource information using the configuration parameters delivered from a network. However, our platform receives and captures only the LTE signal over the air and then enables the estimation of the data relevant to scheduling for all terminals within an LTE cell. After extracting the control channel signal without loss from all LTE subframes, it detects valid downlink control information using the proposed algorithm, which is based on the error vector magnitude of depatterned symbols. We verify the reliability of the developed platform by comparing it with real data from mobile phones and service operators. The average difference in resource block utilization is only 0.28%.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.12
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• pp.4356-4371
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• 2014

When the load in a multi-cell orthogonal frequency division multiple access (OFDMA) system is allowed to excessively increase in face of frequent handover, the cell area becomes smaller than the designed size, and thus continuity of quality of service (QoS) for handover requests cannot be guaranteed. To efficiently support the mobility of a mobile terminal (MT), we should adaptively cope with the resource demand of handover calls. This paper proposes a twofold resource-reservation scheme for OFDMA systems to guarantee continuity of QoS for various mobile multimedia services during MT handover from lightly to heavily loaded cells. Our twofold scheme attempts to guarantee service continuity for handover and to maximize resource allocation efficiency. We performed a simulation to evaluate our scheme in terms of outage probability, handover failure rate, total throughput, and blocking rate.

• ETRI Journal
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• v.34 no.2
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• pp.159-167
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• 2012

In this paper, a new distributed resource allocation algorithm is proposed to alleviate the cross-tier interference for orthogonal frequency division multiplexing access macrocell and femtocell overlay. Specifically, the resource allocation problem is modeled as a non-cooperative game. Based on game theory, we propose an iterative algorithm between subchannel and power allocation called distributed resource allocation which requires no coordination among the two-hierarchy networks. Finally, a macrocell link quality protection process is proposed to guarantee the macrocell UE's quality of service to avoid severe cross-tier interference from femtocells. Simulation results show that the proposed algorithm can achieve remarkable performance gains as compared to the pure waterfilling algorithm.

• Current Industrial and Technological Trends in Aerospace
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• v.7 no.1
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• pp.23-31
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• 2009

Insufficient problem about resource of satellite network frequency and orbit was seriously issued, because commercialization of a satellite has been successfully achieved since 1980s. Therefore, each countries execute an advantageous policy to them for guarantying and protecting satellite network resource and perform study for preoccupying new satellite network resource. Understanding and insight of policy about occupying satellite network resource of world each countries are landmark of satellite network task. In this paper, policies of Japan, Russia and China located around Korea are especially described. Also, in this paper, the administration organization of Japan, Russia and China which are to manage satellite network is described. The KARI(Korea Aerospace Research Institute) secured satellite network frequency and orbit of the KOMPSAT(KOrea Multi Purpose SATellite)-1 and the KOMPSAT-2 and is also going to register satellite network of the KOMPSAT-3 and the KOMPSAT-5. When satellite network coordination with nearby three countries will be needed, understanding of political policy and organization let the Korea acquire coordination agreement of the other administration.

• Journal of Families and Better Life
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• v.9 no.1 s.17
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• pp.81-94
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• 1991

The Purpose of this study is to determine how Korean and United Sates families manage resourcese. Further, socioeconomic and social psychological determinants of frequency of family resoures management will be investigated for each country. Comparision of results well be made to find similarities and differences between Korea and the U.S. Most studies of family resource management have used urban samples, so this study adds to understanding of another segment of the populations. Family resource management variables, as dependent variables, were measured by asking respondents how often they used a variety of wasys to handle finances and time. Independent variables were : (a) total household income, (b) respondents education, (c) respondents ages, (d) householder size, (e) family adaptability, (f) family cohesion, and (g) interpersonal communications. Data for the Korean sample were collected in rural areas of South Korea during summer 1989, U.S. data were collected in two counties of Illinois. The data used in this study include 473 Korean samples and 301 U.S. families. In both samples, the respondent was the financial manager, the person who usually handled the finances and paid the bills. The data were analyzed by frequencys, t-test, and multiple regression analysis methods. As a results, U.S. respondents tended to engage in family resource management more frequently than Korean respondents. This could be attributed to a longer history of consumer education and financial management education taught in the public schools and through the Cooperative Extension Service in the U.S. Social-psycological variables were significant predictors of frequency of family financial management in both samples. the differences in both samples are that, in Korea, frequency of family financial management increased as household size and educational years increased, however, in the United States, the relationships of these variables were not significant. Some similarities and differences were found in Korea and the U.S. families, and this results represents that interpersonal communications are important determinants, even in different cultures. One hadn, the difference of socio-cultural factors result as the difference of some statisical differences. Findings from this study have important implications for research and education, and can be applicated to study of family resource management in other rural areas.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.2
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• pp.298-306
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• 2015

In this paper, we propose an efficient resource allocation scheme for the integrated satellite/terrestrial networks. The proposed scheme is a frequency sharing technique to mitigate the inter-component interferences which can be generated between a satellite beam and terrestrial cells that are operated in the same frequency. The proposed dynamic resource allocation scheme can mitigate the total inter-component interference by optimizing the total transmission power and it can expect a result of which can lead to an increase in capacity. In such a system, the interference situation can be affected by the distributed traffic demands or up/down link communications environments. In this point of view, we evaluate the performance of the total consumed power, the amount of inter-component interference with respect to different traffic distributions and interference environments between the satellite beam and terrestrial systems.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.8A
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• pp.829-837
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• 2008

A cellular system with fixed relays is considered to be a technology that can support high data transmission service to wide areas. However, either inter-cell interference or inter-sector interference that can be produced by adding relays to the cellular system with fixed relays does not guarantee high link performance to deteriorate function, so that resource allocation for avoidance of interference is very much important. In the paper, the cellular system performance with repeater relay has been compared with the cellular system performance with relay, and cell coverage expansion at the use of relay repeater has been compared. To compare, this paper has suggested resource allocation method to avoid inter-cell interference and inter-sector interference at installation of fixed relay on the cellular system. The proposed method can allocate different frequency resources on adjacent base stations and relays to reduce interference and to expand high data transmission area, and all of frequency bands are used at each sector to elevate efficiency of the frequency when base stations and relays operate simultaneously.

• Journal of Family Resource Management and Policy Review
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• v.13 no.3
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• pp.207-226
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• 2009

The purposes of this study are to evaluate the research trends of articles published in the Journal of the Korean Family Resource Management Association from 1997 to 2008, and to identify the contributions as well as the inherent limitations of these articles in the field of family resource management. For these purposes, this study analyzed 3 types of research trends: research topic, research method including data analysis, and research subject. The findings of this study are as follows. First of all, the study shows that most number of researches are conducted on management subjects, followed by management practice and management theory. Secondly, regarding the frequency of the research method, the empirical researches are the most prevalent method employed by the researches, over literature or practice researches. Thirdly, it is noted there are more quantitative researches than qualitative ones. Finally, there are a lot more researches carried out on the traditional household than those of vulnerable households.

• Journal of Information Technology Services
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• v.15 no.2
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• pp.125-155
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• 2016

By reclassifying and reinterpreting the factor variables that were used in precedent studies on company informatization by research theme and perspective on them success factor, the present study tried to examine how different the factor variables are in frequency of use and by period, and how importantly they were considered by research theme and perspective on its success factor, combining them with the studies done on mechanism point of view. The key findings of this study are as follows. First, it was found that the frequency of using mechanism variables, which are reclassified based on SER-M perspective, has gradually increased since 1990s. While the frequency of using resource factors sharply increased in 1990s, it decreased from 2000s. It indicates that more studies were conducted of mechanism factors other than resource factors from the early 2000s. Second, when looking at those variables reclassified by research them, it was found that such theme as decision maker, environment, and resource factors were more used than other research themes in the studies on the measuring factors of informatization. Mechanism factors turned out most used among overall research themes. In particular, they were more frequently used in studies related to the performance of informatization. This result evidences that mechanism-related variables are more importantly considered in the studies than other factors. This study produces a practical implication: what factors companies have to manage and secure intensively to attain successful informatization. In addition, this study helps companies seeking informatization understand and take advantage of SER-M factors on the basis of knowledge in the transitional process of the factor variables used in studies by period. It is expected that CIO can use the key findings of this study in monitoring the factors by the stage of informatization.

• Journal of the Korean Dietetic Association
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• v.16 no.2
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• pp.160-177
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• 2010

The purpose of this study was to identify job frequency and the training needs of dieticians in elderly health care facilities. This study consisted of dieticians working in elderly health care facilities with a capacity of over 50 elderly. Survey questionnaires were distributed to 190 dieticians through the mail and 106 dieticians (55.8%) participated in this study. The results of the survey showed that dieticians in elderly health care facilities frequently performed the following job: work management, safety and sanitation management, purchase management, human resource management, finance management, nutrition management, and marketing management. The job frequency in safety and sanitation management (p<0.05) and nutrition management (p<0.01) areas were significantly different by the number of dieticians. Safety and sanitation management and menu management were considered job areas that needed further training and education. Dieticians in elderly health care facilities responded that the following jobs should require not only training but are also frequently performed: safety and sanitation management, menu management, work management, and human resource management. Thus, based on the results of this study, continuous training programs in these fields should be offered to satisfy the needs of dieticians.