• Journal of Ubiquitous Convergence Technology
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• v.1 no.1
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• pp.23-27
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• 2007

Fruition for a diverse uIT(Ubiquitous Information Technology) service is currently required through the convergence of what is known as ubiquitous computing technology. In recent years, with the rapid growth of the need for information services, heavier demands have been made upon the supply of high-quality multimedia services that require a high bandwidth. Today, various home network solutions have been proposed to manage these service smoothly and a system able to deal with various types of network traffic without delays. In addition, in established home network environments that mix wired and wireless networks, along with the steady evolution of wireless network technology and the earnest development of ubiquitous computing technology, sensor-based wireless networks have emerged as a core solution for home networks. In this paper, a sensor network-based home control system supporting the next generation home gateway system for ubiquitous home environments is designed and implemented.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.1
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• pp.115-121
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• 2009

Web 2.0 has become the face next generation Web among the business world and research community. Web 2.0 is instant superficial gratification of people. On the other hand, Semantic Web is deep, meaningful and lasting relationship with data. So, it is difficult to apply the Semantic Web to the real world. In this paper, a platform for educational services using the Semantic Web and Web 2.0 is proposed. The proposed platform is based mix of the Semantic Web and Web 2.0, so it is useful to apply in the real world applications. Two services are presented, one is a semantic email system and the other is a cyber study space. The cyber study space adjusted each student is presented. The study environment is called iStudySpace that has personal scheduler, study status plan table, personalized search engine and several gadgets. Finally characteristics and limitations of the Semantic Web and Web 2.0, the organization and components of the platform, evaluation of iStudySpace are shown.

• Computers and Concrete
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• v.11 no.6
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• pp.587-602
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• 2013

In the current study, a method for concrete compressive strength prediction (based on cement strength class), incorporated in a software package developed by the authors for the estimation of concrete service life under harmful environments, is presented and validated. Prediction of concrete compressive strength, prior to real experimentation, can be a very useful tool for a first mix screening. Given the fact that lower limitations in strength have been set in standards, to attain a minimum of service life, a strength approach is a necessity. Furthermore, considering the number of theoretical attempts on strength predictions so far, it can be seen that although they lack widespread accepted validity, certain empirical expressions are still widely used. The method elaborated in this study, it offers a simple and accurate, compressive strength estimation, in very good agreement with experimental results. A modified version of the Feret's formula is used, since it contains only one adjustable parameter, predicted by knowing the cement strength class. The approach presented in this study can be applied on any cement type, including active additions (fly ash, silica fume) and age.

• International Journal of Highway Engineering
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• v.15 no.1
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• pp.11-21
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• 2013

PURPOSES: As pavement generally provides service shorter than an expected life cycle, maintenance cost increases gradually. In order to help extending the service life and reduce maintenance cost, a new multi-functional composite pavement system is being developed in Korea. METHODS: This study is a part to develop the multi-functional composite pavement and is to investigate the mechanical performances of fiber-reinforced lean concrete for pavement subbase. The inherent problem of fiber reinforced concrete is dispersion of fibers in concrete mix. This study additionally evaluated fiber dispersion characteristics with respect to different fiber types. RESULTS: From the test results, the compressive strengths of the concretes satisfied the required limit of 5MPa at 7days. The standard deviation of the measured number of fibers were lower in the order of nylon, steel fiber and polypropylene. CONCLUSIONS: Reject ash was shown to be satisfactory as a replacement material to Portland cement in lean concrete base. The fiber volume fraction is suggested to be 0.4% even though the fracture toughness did not vary significantly with respect to fiber types. However, fracture energy absorbed up to complete failure increased with the increased fiber volume fraction increment.

• Journal of Industrial Convergence
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• v.15 no.2
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• pp.1-6
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• 2017

This paper illustrates key features of an enterprise employment simulation which integrates a system dynamic feedback model with a cost-effectiveness optimisation capability utilising genetic algorithms. Its core is a 3-dimensional array structure tracking staff numbers by rank, by time-in-rank, by years-of-service. The resultant model, which could readily be adapted to non-Defence use, can identify, given user specification of any mix of employment rules, the likely patterns of employment behaviour including: resultant time-in-rank and years-of-service profiles; ability of a Unit to fill all positions to target strength; ability to fill promotional positions within normal rules for substantive promotion; need to fill promotional positions using rules for temporary promotion or transfer from outside; necessary recruitment pattern to sustain target strength.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.6
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• pp.1135-1142
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• 2017

In this paper, we propose an algorithm that can automatically mix the screen and sound by tracking the change of the sound data according to the screen change so that the real sound can be implemented in the personal broadcasting service. Since the personal broadcasting service is often broadcasted lively, it should be convenient to have a real-time mixing. Through experiments, it was confirmed that the sound pressure changes in a wide range in the high frequency band related to the clarity for understanding according to the rotation angle change of the screen. Regression analysis of the sound pressure changes at 2kHz, 4kHz, and 8kHz, The attenuation change of sound pressure was observed at the slope of -1.17, the slope of -2.0, and the slope of -2.44 for each frequency. Therefore, these experiment results can be applied to the VR service. This study is expected to be useful data in the implementation of personal broadcasting service.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.236-245
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• 2021

It is very important for structure designer to understand the service life variation since a wide range of service life is evaluated with changing exposure conditions and design parameters. Recently, for zero-carbon, waste plastic has been used for fuel for clinker production and this yields increase in chloride content in cement. This study is for evaluation of changing service life in the concrete with increasing initial chloride content due to usage of plastic-SRF(Solid Refuse Fuel) considering various exposure conditions and design parameters. For this, 4 levels of initial chloride content were assumed, and the service life was assessed using LIFE 365 program considering various environmental conditions including 3 levels of surface chloride content. As for analysis parameters, critical/initial chloride content, blast furnace slag powder replacement ratio, W/B(Water to Binder) ratio, cover depth, and unit mass for binder are adopted. Service life decreases with increasing initial chloride content and a significant reduction of service life is not evaluated permitting up to 1,000ppm of initial chloride content. With increasing slag replacement ratio, a longer service life can be secured since blast furnace slag powder has the effect of reducing the diffusion of external chloride ions and fixing the free chloride. It is thought that increasing initial chloride content up to European standard is helpful for enhancing sustainability and reducing carbon emission. Though the reduction in service life due to an increase in the initial chloride content is not significant in slag-concrete with low surface chloride content, careful consideration for mixing design should be paid for the exposure environment with high surface chloride content.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.3237-3243
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• 2012

The purpose of this study is to analyze city's built environment that have influence on residents' health in the 40 small and medium-sized cities. In the study, landuse, urban form and facility accessibility of cities and other socio-demographic variables were used as explanatory variables, and a statistical analysis was carried out by applying multi-level analysis. Analysis shows that a high level of population density lower the obesity, and a high level of landuse-mix have a positive effect on EQ-5D & hypertension. In terms of urban form and facility accessibility, residents show a high level of obesity in an environment where roads are closely connected and access to bus service is bad. Finally, as more access to open space have a positive effect on EQ-5D. Therefore, landuse-mix, access to public transportation and open space should be used for planning factors to make a health improvement plan in cities.

• The Journal of the Korea Contents Association
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• v.15 no.9
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• pp.509-526
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• 2015

The study investigated the N-Screen strategies of paid digital contents of foreign newspapers belonging to advanced companies: USA, United Kingdom, and Japan. This research employed the time to launch paid digital content business, whether or not to segment market, and 4p marketing mix strategies for analyzing the strategies. The results show that the strategies, starting around the year 2000, had experience chasm, and then revived since the year 2010, when the penetration rate of mobile devices proliferated. Most newspapers still supply contents under the assumption that they paly in a mass market. The items of paid digital contents are mainly composed of e-paper and digital contents. Regarding the price strategy, soft paywall and combination paywall are largely used. Distribution strategy is subject to whether or not to discriminate the path of digital contents. As for promotion strategy, bundling strategy with newspaper is mostly utilized. The difference between western countries and Japan was found in term of the free trial service.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3939-3943
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• 2016

Background: According to recent statistics, the breast cancer rate is growing fast in developing countries. In North West of Iran, the incidence of breast cancer after esophageal and gastric cancers has the highest rate. Previous studies have also indicated that women in this region show reluctance to do breast cancer screening. There is a great need for change to promote breast cancer screening among women. Social marketing is a discipline that uses the systematic application of commercial marketing techniques to promote the adoption of behavior by the target audience. Materials and Methods: In the present qualitative study, thirty-two women with breast cancer were interviewed about their experiences of breast cancer screening. A semi-structured interview guide was designed to elicit information specific to the 4 P's in social marketing. Results: Three main categories emerged from the analysis: price, service and promotion. Subcategories related to these main categories included factors effective in increasing and decreasing cost of screening, current and desirable features of screening services, and weakness of promotion. Conclusions: Screening programs should be designed to be of low cost, to meet patients' needs and should be provided in suitable places. Furthermore, it is essential that the cultural beliefs of society be improved through education. It seems necessary to design an executive protocol for breast cancer screening at different levels of primary health care to increase the women's willingness to undergo screening.