• International Journal of Highway Engineering
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• v.4 no.2 s.12
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• pp.1-8
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• 2002

Latex modified concrete(LMC) became to be applied as a new material for newly constructed bridge deck overlays in Korea due to its excellent bond strength, flexural strength and impermeability against water and chloride. However, it could not be adopted at repair job site because of its long curing time required. Thus, a research on latex modified concrete with rapid-setting cement(RSLMC) is necessary if it could develope the sufficient strength for early opening to traffic. This study focused on the durability of latex modified concrete with rapid-setting cement mainly on water permeable resistance and freeze-thaw resistance. The main experimental variables were latex contents(0, 5, 10, 15 and 20%) and antifoamer contents (0, 1.6, 3.2, 4.8 and 6.4%). Test results show that the permeability of RSLMC is very low indicating below 100 coulombs at 15% of latex contents at all antifoamer contents. The freeze-thaw resistance of RSLMC maintains above 90% of relative dynamic modulus at 3.2% of antifoamer content until 300 freezing-thawing cycles.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.58-62
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• 2008

'Miso', a new variety of oyster mushroom was developed for the bottle culture at the Chungnam Agricultural Research & Extension Services. Its mycelium grew rapidly with $8.4{\sim}8.6\;mm/day $ at $25{\sim}28^{\circ}C$ on PDA medium. The optimum pH of the mycelial growth was pH 5.0. It took 24 days for the primitive primordium formation after inoculation on pine sawdust media mixed with 20% wheat bran. Fruiting body color was white, and the shape of pileus was convex-umbonate. In the bottle culture, the yield was 115.7 g per 850 ml bottle. Stipe length was about 54 mm, the number of stipe per bottle was 18.1, the size of pileus was 28 mm, and gill was crowded. The moisture content of 'Miso' was lower than that of Jangan No.5 and Wonhyeong No.1, and contents of protein, ash and sugar of 'Miso' were higher than those of other varieties, and tannin acid content of 'Miso' was lower than that of others. On the basis of AFLP analysis, the 'Miso' was distinct not only from Wonhyeong No.1, but also from their closest relative, oyster mushrooms.

• Journal of the Korea Convergence Society
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• v.6 no.4
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• pp.99-105
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• 2015

In order to prevent the environmental pollution nowadays, the mobile device for one person of cruiser board not used with the fossil oil has been noticed. This study aims to analyze the property of cruiser board due to the shape by carrying out the structural analysis for the safe design of cruiser board. Two models of the existing cruiser board and the cruiser board with new configuration are designed. As the structural analysis was carried out by using the finite element analysis program, the durability by deformation, stress and fatigue life was investigated. In the study result, the model of cruiser board with new configuration has the maximum deformation of 0.000971mm, the maximum stress of 0.936MPa and the fatigue life from 1827.7Cycle to $1.887{\times}105Cycle$. As all study result values at the new model became better than the existing model, the new model was seen to become more adequate at using than the existing model. This study result can be contributed to the safer and durable design of cruiser board. And it is possible to be grafted onto the convergence technique at design and show the esthetic sense.

• Journal of the Korea Concrete Institute
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• v.20 no.5
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• pp.543-548
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• 2008

Solid hydrated by hydro-thermal synthesis reaction is cured two times, the first curing is the steam curing at atmospheric pressure and the second one is a high-pressure steam curing, that is autoclaving. Steam curing is to acquire the proper strength for the resistance of treatment in the first curing process, it was not evaluated properly so far. Because of ignorance about curing, some engineers even think that the dry curing is better than the steam curing. The relation between compressive strength of solid hydrated by hydrothermal synthesis reaction and curing condition are presented in this paper. In order to investigate the effect of curing on the strength properties of specimen, the hydration behavior of solid hydrated by hydro-thermal synthesis reaction has been studied over curing condition using XRD, DT-TGA and porosimeter, SEM analysis technique. The results show that the specimens which are cured with blended method of dry and steam curing appear to have better strength properties than that of dry curing and steam curing. Also, there are significant difference of hydration behavior among curing condition in the solid hydrated by hydro-thermal synthesis reaction.

• Journal of the Korea Concrete Institute
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• v.20 no.5
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• pp.557-563
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• 2008

Recently, the amount of disposed construction materials like demolished concrete is growing fast and the shortage of natural concrete aggregate is becoming serious. Therefore, recycling of aggregate extracted from the demolished concrete is getting important and use of the recycled aggregate for concrete has been seriously considered. However, the use of the recycled aggregate even for low performance concrete is very limited because recycled aggregate which contains large amount of old mortar has very low quality. Therefore, removing the paste sticked to the recycled aggregate is very important in the manufacturing of high quality recycled aggregate. We have studied a series of research according to complex crushing method, which is removed the ingredient of cement paste from recycled fine aggregate using both the low speed wet abrasion crusher as mechanical process and the acid treatment as chemical processes. This paper is to analyze the quality of the recycled fine aggregate produced by those complex method and investigate optimum manufacturing condition for recycled fine aggregate by the design of experiments. The experimental parameters considered are water ratio, coase aggregate ratio, and abrasion time. As a result, data concerning the properties of recycled sand were obtained. It was found that high quality recycled fine aggregate could be to obtain at the condition of the fifteen minute of abrasion-crusher time and the over 1.0 of recycled coarse aggregate ratio.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2393-2399
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• 2013

In this paper, we proposed a method to screening of Alzheimer's disease (AD) from Raman spectra of platelet with synthesis of basis spectra using singular value decomposition (SVD). Raman spectra of platelet from AD transgenic mice are preprocessed with denoising, removal background and normalization method. The column vectors of each data matrix consist of Raman spectrum of AD and normal (NR). The matrix is factorized using SVD algorithm and then the basis spectra of AD and NR are determined by 12 column vectors of each matrix. The classification process is completed by select the class that minimized the root-mean-square error between the validation spectrum and the linear synthesized spectrum of the basis spectra. According to the experiments involving 278 Raman spectra, the proposed method gave about 97.6% classification rate, which is better performance about 6.1% than multi-layer perceptron (MLP) with extracted features using principle components analysis (PCA). The results show that the basis spectra using SVD is well suited for the diagnosis of AD by Raman spectra from platelet.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.324-334
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• 2019

This study investigates the characteristics of patients hospitalized at a convalescent hospital, by considering patient groups based on their medical record information. It further analyzes and correlates the factors, thus providing basic data required to improve the patient classification system at convalescent hospitals. The data includes total information of 213 medical records of patients discharged from a convalescent hospital in the Jeonbuk region during a period of one year, from January to December 2016. The study examines and correlates the days of hospitalization and the number of diseases, revealing a positive correlation having a correlation coefficient, thereby indicating that infliction with a greater number of diseases results in longer hospitalization. Based on these findings, the study raises the need to revise and supplement items on the patient assessment report to help determine the patient groups and identify medical efforts to be actually provided to patients. In addition, a proper care service system for each patient group based on their respective problems that are intensively managed according to the patient groups will be an essential element in the efficient management of convalescent hospitals. Furthermore, an important task addressed will be in managing the health of the elderly population at the national level.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.619-623
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• 2018

This paper aimed to design a computer course teaching-learning strategy for (m-learning?) to be used in a Problem Based Learning (PBL) environment. The research findings were as follows. Firstly, learning contents were provided as educational tools for mobile device usage. The educational contents provided were designed for effective usage on mobile devices, such as smartphones, thereby making mobile devices suitable for use as learning tools. Secondly, learning contents for PBL were provided. PBL problems (for computer engineering courses) were made with the principles of teaching plans. The learning objectives were achieved through the problem-solving progress of the learners and their self-directed and cooperative learnings. Thirdly, learning resources were provided that were easily accessible through smartphones, laptops and PDAs. This study is about the PBL instructional design of creative engineering design subjects, which aims to foster talent. The PBL model developed in this study consists of Analysis, Design, Development, Implementation, and Evaluation. We made a plan for creative engineering design subjects based on PBL, and focused on the process of PBL. This research was able to establish the basis for PBL usage in Engineering Schools and help achieve its ultimate goal of endowing professional intellectuals with creative problem-solving abilities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.561-569
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• 2020

This study was done to develop indicators for cities that can be used in the long term and in a sustainable manner. Activation indicators were developed to improve the resilience in the downtown area of Seo-gu, Incheon. Preliminary indicators were derived from prior studies on similar indicators of resilience for urban regeneration, and an expert opinion survey was conducted to analyze the suitability and importance of the indicators. Activation indicators were established for improving urban resilience in six areas: population stability, social inclusion, industrial diversity, local productivity, environmental sustainability, and social-based convenience. From 60 preliminary indicators, 42 indicators were selected through the expert opinion surveys for securing an economically active population, establishing a living infrastructure, improving the settlement environment, and upgrading industry to reflect the characteristics of the West, including industrial complexes. It was found that diversification is necessary. Further study is still necessary to improve the objectivity of the indicators and calculate a resilience index. The significance of this study is that it looks at quantitative indicators, complements other studies on regional decline diagnosis, and presents realistic alternatives suitable for domestic situations based on the concept of resilience.

• Journal of Korean Library and Information Science Society
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• v.46 no.3
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• pp.349-379
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• 2015

In the 1980's opening 79 of the end of 2013, the National Public Library that had been It was 885 its opening remains in effect. Especially in the 2000s after 60% of the whole library, a library erected since the advent of the library is enough to be a significant quantitative expansion. The resulting to make a qualitative aspect of public libraries and increase users' needs for efficient space configuration. IIn particular, the user is to serve the needs of digital reading room and the increase of the cultural training changes after 2000 years ago, and appears as due to the implications of space configuration in an age-appropriate library space off the rate plan is a necessary point. The study in the 1980s-1990s, built public library established since the year 2000 centered on public library mutual comparative analysis of space configuration form. Book reading function was the conservation and highlight 1980-1990s and considered by the side of the users culture area extended since the 2000s, public library takes the difference between the ratio of the area of the facility by the area in which you can meet the standards required and the age.