• Journal of Korea Multimedia Society
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• v.7 no.5
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• pp.689-697
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• 2004

Rapid advances in mobile computing and the availability of wireless communications will soon provide mobile users with the ability to access data regardless of the location of the user or of the data. SRA(Static Replica Allocation) that is traditional scheme has been used for the replication method on the server. This replicates the data on the replica server after a moving host has been transferred to the cell. This strategy is simple and can easily relocate data. However, if a mobile user does not exist in the cell, the replicated data can be deleted in order to maintain data consistency. In addition to, if the mobile host leaves from replicated cell, it is difficult to access data in terms of replication route. Therefore, this paper proposes a new method of relocation based on data consistency strategy called USRAC(User Selection Replica Allocation based on Consistency) and also analyzes access cost according to the moving rate of mobile users, according to the access rate of mobile hosts, and according to the number of cells of mobile users and mobile hosts.

• Journal of Science and Technology Studies
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• v.15 no.2
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• pp.163-189
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• 2015

While Science tries to be far from Society, it actually does yearn for the trust from Society, on the other side. Its efforts getting back the trust has been witnessed with its fast evolution, consistent distrust from Society and Scientists' accountability with investment of public fund. Furthermore, many scholars have argued that there is the need to integrate science and society. In this regards, this paper explores how to integrate both spheres by participatory evaluation. To identify how the participatory evaluation works and should be, three main issues are mentioned. One is about evaluation methods; Objective-oriented and Behaviour aspects. Second is about prerequisite factors; sharing scientific language and changed recognition between civil society and scientists. Third is about challenge to be tackled; epistemological gap among evaluators and complex index. Under these issues, this paper sets out that the participatory evaluation should adopt the appropriate evaluation methodology. Last but not least, self-recognition and motivation by evaluators themselves are important factors, along with societal system which can take participatory evaluation.

• The Journal of Bigdata
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• v.6 no.1
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• pp.1-12
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• 2021

The rapid growth of mobile-based online shopping and the appearance of untact business initiated by COVID-19 has led to an explosive increase in demand for logistics services such as delivery services. In order to respond to the rapidly growing demand, most logistics and distribution companies are working to improve customer service levels through the establishment of a full-filament center in the city center. However, due to social factors such as high land prices and traffic congestion, it becomes more difficult to establish the logistics facilities in the city center. In this study, it has been proposed the way to choose the candidate locations for the shared distribution centers among the space nearby the tall-gate which can be idle after the smart tolling service is widely extended. In order to evaluate the candidate locations, it has been evaluated the centralities of all candidates using social network analysis (SNA). To understand the result considering the characteristics of centrality, the network structure was regenerated based on the distance and the traveling time, respectively. It is possible to refer the result of evaluation based on the cumulative relative importance to choose the best set of candidates.

• International Area Studies Review
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• v.14 no.3
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• pp.502-523
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• 2010

A federal system speaks for a political system that the principle of the common sovereignty among the local governments is applied. The basic purpose of the system is to make institutional devices capable of striving for the mutual cooperation in a greater political unit, reflecting a minority race's right and demand by decentralizing a state authority into the individual region. The basic purpose for formation of a federal system is realized when a form for the supplement of political elite personnels has a autonomous nature by the subject of a federal structure. During from B.Yeltsin to V.Putin, a form for the supplement of political elite personnels into the local governments has changed by a political purpose of a central government, In company with this change, the character of federalism in Russia has been also changed. Accordingly, this study has treated a subject about how the political elite personnels of local assembly men, governors of a state, assemblymen of both Houses, and the president of Russia are suppled, and also how such a form for the supplement of political elite personnels has changed the character of federalism in Russia.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.1
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• pp.55-70
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• 2018

Recently, as shared transportation services has expanded, integrated mobility services that link personal transportation and public transportation are paid attention. To do this, it is necessary to analyze trip mode chaining behavior. This study analyzed the characteristics of the trip mode chaining behavior using the 2010 travel diary survey in Seoul, and analyzed factors to affect mode choice of trip chaining through the multinomial logit model. The transportation means were classified into passenger cars, city buses, intercity buses, railways, taxis, and others, and 25 trip mode chaining types were identified. Among them, the trip share connected between city bus and railways was the highest. It was also found that the trip mode chaining occurred mainly at commuting and in the morning and afternoon peak. According to the model results, the mode choice of trip chaining is significantly influenced by individual attributes (sex and age), household attributes (car ownership and income), trip attributes (trip purpose, trip time and trip length), and arrival area attributes (number of subway lines and bus lines, ratio of commercial area, land use mix and central region).

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.8
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• pp.9-18
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• 2004

The IEEE 802.11 Distributed Coordination Function(DCF) protocol provides a contention-based distribution channel access mechanism for stations to share the wireless medium. However, the performance of the DCF drops dramatically in terms of throughput, delay and delay jitter as the number of active stations becomes large. In this paper, we propose a simple and effective scheme, called DCF/VG(Distributed Coordination Function with Virtual Group), for improving the performance of the IEEE 802.11 DCF mechanism. In this scheme, each station independently decides the virtual group cycle using the information provided by the carrier sensing mechanism. The virtual group cycle consists of one or more virtual groups and a virtual group includes an idle period and a busy period. Each station operates in only one out of several virtual groups of the virtual group cycle and does not operate in the others. In other words, each station decreases its backoff counter and tries to transmit a packet only in its virtual group like the IEEE 802.11 DCF. Performance of the proposed scheme is investigated by numerical analysis and simulation. Numerical and simulation results show that the proposed scheme is very effective and has high throughput and low delay and jitter under a wide range of contention level.

• The Journal of Bigdata
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• v.5 no.1
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• pp.11-27
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• 2020

In this paper, we developed a big data platform to store, process, and analyze effectively on such education longitudinal study data. And it was applied to the Seoul Education Longitudinal Study(SELS) to confirm its usefulness. The developed platform consists of data preprocessing unit and data analysis unit. The data preprocessing unit 1) masking, 2) converts each item into a factor 3) normalizes / creates dummy variables 4) data derivation, and 5) data warehousing. The data analysis unit consists of OLAP and data mining(DM). In the multidimensional analysis, OLAP is performed after selecting a measure and designing a schema. The DM process involves variable selection, research model selection, data modification, parameter tuning, model training, model evaluation, and interpretation of the results. The data warehouse created through the preprocessing process on this platform can be shared by various researchers, and the continuous accumulation of data sets makes further analysis easier for subsequent researchers. In addition, policy-makers can access the SELS data warehouse directly and analyze it online through multi-dimensional analysis, enabling scientific decision making. To prove the usefulness of the developed platform, SELS data was built on the platform and OLAP and DM were performed by selecting the mathematics academic achievement as a measure, and various factors affecting the measurements were analyzed using DM techniques. This enabled us to quickly and effectively derive implications for data-based education policies.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.3
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• pp.69-76
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• 2008

This work proposes a 12b 1kS/s 65uA 0.35um CMOS algorithmic ADC for sensor interface applications such as accelerometers and gyro sensors requiring high resolution, ultra-low power, and small size simultaneously. The proposed ADC is based on an algorithmic architecture with recycling techniques to optimize sampling rate, resolution, chip area, and power consumption. Two versions of ADCs are fabricated with a conventional open-loop sampling scheme and a closed-loop sampling scheme to investigate the effects of offset and 1/f noise during dynamic operation. Switched bias power-reduction techniques and bias circuit sharing reduce the power consumption of amplifiers in the SHA and MDAC. The current and voltage references are implemented on chip with optional of-chip voltage references for low-power SoC applications. The prototype ADC in a 0.35um 2P4M CMOS technology demonstrates a measured DNL and INL within 0.78LSB and 2.24LSB, and shows a maximum SNDR and SFDR of 60dB and 70dB in versionl, and 63dB and 75dB in version2 at 1kS/s. The versionl and version2 ADCs with an active die area of $0.78mm^2$ and $0.81mm^2$ consume 0.163mW and 0.176mW at 1kS/s and 2.5V, respectively.

• Journal of Korean Home Economics Education Association
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• v.33 no.2
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• pp.1-25
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• 2021

The purpose of this paper is to explore ways to prepare for the high school credit system in the home economics educational community through the case of high school credit system research school operation. To this end, the operation process of H high school in Gangwon-do, which operated a high school credit system in 2019, was monitored for 5 months, and surveys and interviews were conducted with students, parents, and teachers to determine the operation of the curriculum. Suggestions based on the case of H high school's operation of the high school credit system for home economics educational community are as follows. Home economics teachers should make active efforts to provide attractive and meaningful home economics lessons to their students by improving instruction and assessment, and implementing a variety of elective courses within the subject of home economics, including collaborative online curricula. Home economics teacher communities and related associations should build a solid network that connects local home economics subject research groups, share information related to curriculum operation, and use it as a channel for disseminating class research results. Home economics teacher training institutions should innovate the curriculum to help prospective teachers develop the ability to guide multiple classes in line with the changing teacher training policy, and develop and provide high-quality online and offline programs for field teacher re-education.

• Cross-Cultural Studies
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• v.41
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• pp.113-140
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• 2015

This paper explains how the basic and instinctive emotion "joy" is verbally expressed in Russian and Korean. In particular, the main concern of this pater is on the cultural context with which the emotion "joy" is related and the ways in which the emotion "joy" has a wide range of uses. The semantic and pragmatic characteristics of the uses of the expression "joy" can be explained through the cultural and historical backgrounds in both languages. In Russian, joy has two variants, radost' and udovol'stvie. It is very difficult to distinguish a significant difference between them; however, the former is mainly connected with more mental, spiritual, cultural, and religious contexts, whereas the latter is mainly related with more concrete, instantaneous contexts and daily life. The former produces an impression that has a more wide, spiritual, and macroscopic attitude toward a situation, whereas the latter produces an impression that has a microscopic and instantaneous attitude toward a situation. Compared with the Russian expressions, the Korean equivalents, 기쁨 and 즐거움, have a very similar opposition like that of the Russian. The former is based on a more logical and causal relation between an anticipation or desire and the current situations, whereas the latter is based on the participation of speakers in a situation and has a very instantaneous characteristic, like a udovol'stvie in Russian. Thus, it can be reasonable argued that the Russian udovol'stvie and the Korean 즐거움 share many similar semantic properties. In brief summary, in both languages there exists two distinctive variants that show a privative opposition to express the emotional concept of joy.