• Geomechanics and Engineering
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• v.24 no.5
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• pp.419-430
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• 2021

Investigation on the compressibility and shear strength of compacted loess is of great importance for the design and operation of engineering infrastructures in filling area. In this study, the mechanical behaviors of Yan'an compacted loess are investigated at various dry densities and water contents by conducting one dimensional compression and direct shear tests. And the elastic compressibility, plastic compressibility, yield stress and strength are obtained from the experiments. Results show that when water content increases, plastic compressibility parameter increases, but yield stress decreases. However, the increase of dry density leads to a decrease in plastic compressibility parameter but an increase in yield stress. In addition, elastic compressibility parameter is found to be a constant which is irrelevant to water content and dry density. As for strength, cohesion and internal friction angle is directly proportional to dry density, but inversely proportional to water content. Moreover, the mercury intrusion porosimetry (MIP) and scanning electron microscope (SEM) tests were also performed to observe the pore size distribution and microstructure of the specimens. Finally, by using results of MIP and SEM tests, the compressibility and strength behaviours of Yan'an compacted loess are explained from the perspective of pore-size distribution and microstructure.

• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.4
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• pp.44-52
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• 2024

This study attempts to derive measures to improve content claims of free antibiotic livestock products(FLP) through analyzing situations for the FLP market and results of survey for its providers. Recently the number of certified farms has been decreasing, but shipments per farm has been increasing. Furthermore as the COVID-19 has increased health and environmental concern, shipments of FLP have showed a steady increase. The distribution channel of FLP, regardless of varieties, is similar to that of general livestock products(GLP). The major results from survey for providers of FLP are little difference in between content claims of GLP and FLP and low utilization of FLP in production of livestock processed products compared with its shipments. The policies for content claims of FLP suggested by this study are permission of FLP authentication labelling for livestock processed products and permission of those which contain FLP over 70% in the first step.

• Journal of environmental and Sanitary engineering
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• v.7 no.1
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• pp.87-94
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• 1992

In order to investigate the content of heavy metals in soil according to vertical profiles, 72 soil samples were collected from 4 sampling sites : Ulchiro-2 ga, Dugdo, Sungnaedong, and Amsa- dong. The content of mercury was measured by a mercury analyzer and those of lead, copper and zinc were measured by an atomic absorption spectrophotometer. From the results of this study, it was shown that the content of heavy metals decreased gradually from the surface soil to the 2 m- depth soil. But, there was no difference in the contents of the heavy metals in the 3m, the 4m and the 5m-depth soil.

• Electronics and Telecommunications Trends
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• v.35 no.5
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• pp.123-133
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• 2020

With the development of artificial intelligence (AI) and 5G technology, an ecosystem of digital content is gradually becoming intelligent, immersive, and convergent. However, there is not enough ultra-realistic content for the ecosystem. For ultra-realistic content services, creative content technologies using AI are being developed. This paper introduces the trends in and prospects of creative content technologies such as 3D content creation, digital holography, image-based motion recognition, content analysis/understanding/searching, sport AI, and content distribution.

• Geomechanics and Engineering
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• v.31 no.5
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• pp.519-527
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• 2022

Shear failure in soil is the primary cause of most geotechnical structure failures or instability. Soil water content is a significant factor affecting soil shear strength. In this study, the shear strength of samples with different water contents was tested. The shear strength, cohesion, and internal friction angle decreased with increasing water content. Based on the variation of cohesion and internal friction angle, the water content zone was divided into a high-water content zone and low-water content zone with a threshold water content of 15.05%. Cohesion and internal friction angle have a good linear relationship with water content in both zones. Environmental Scanning Electron Microscopy (ESEM) test presented that the aggregates size of the compacted loess gradually increases with increasing water content. Meanwhile, the clay in the compacted loess forms a matric that envelops around the surface of the aggregates and fills the inter-aggregates pores. A quantitative analysis of bound water and free water under different water contents using a nuclear magnetic resonance (NMR) test was carried out. The threshold water content between bound water and free water was slightly below the plastic limit, which is consistent with the results of shear strength parameters. Combined with the T2 distributions obtained by NMR, one can define a T2 relaxation time of 1.58 ms as the boundary point for bound water distribution without free water. Finally, the effects of bound water and free water on shear strength parameters were analyzed using linear regression analysis.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.932-941
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• 1993

High moisture content of barley seeds, which were carried to the laboratory within 10 minutes after harvest, were stored in air tight bottle at constant temperature, and the individual moisture contents the grains were measured at predecided tim intervals. The theory of predicting the moisture movement between two kinds of different moisture content grains was tried to apply to the prediction of the moisture distribution and tried to apply to the prediction of the moisture distribution and the comparison of the predicted values with the observed dta showed the good suitability of the theory. The shape of the moisture distribution predicted form the theory were similar to the observed ones for the temperature range of 10 to $50^{\circ}C$. This study will be useful in designing the mix-storage facility or dryer.

• Journal of Distribution Science
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• v.15 no.8
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• pp.65-73
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• 2017

Purpose - Although e-learning has this advantage, currently many organizations have failed to recognize the necessity for basic e-learning educational training. It follows that practitioners working in the above organizations face the difficulty of having to find educational training processes of boosting their capabilities by themselves, rather than being able to utilize the educational training processes offered by e-learning. So of their own accord, learners have considered the necessity of information relating to being able to choose between high quality educational training processes. The purpose of this study is to propose opening e-learning content information for enabling an efficient choice of learning processes related to e-learning. Research design, data, and methodology - To pinpoint the items of e-learning content information, the study was initiated according to the following process. First, information relating to e-learning content (offered on e-learning websites) was researched. Second, based on the items of information which emerged from the research, selection and validity verification took place with 5 e-learning specialists as the subjects. Third, the opinions of adult learners at K University were collated relating to the items of information which emerged from the research. Results - The e-learning content information was comprised of 16 items in order to improve the choosing process for learner's e-learning contents. The analysis results showed that when learners were choosing e-learning processes, the most highly considered item was 'mobile support' (4.35). Following this (in order) were 'tuition fees' (4.30), 'certificate issuing' (4.23), and 'awareness of educational institution' (4.18). The least considered items were 'recruiting learners' (3.01) and 'tutor support' (3.18). Conclusions - The 16 items of e-learning content information in this study, were deemed to be helpful to learners in providing them with a choice of desirable e-learning process when this process was offered to them. Following this, there is a need for service institutions offering e-learning processes to make public the information suggested by this study. Research into educational methods additionally points to a necessity for not only e-learning forms, but also offline educational methods and a combination of blended learning to be offered and run parallel to e-learning.

• Journal of the Korean GEO-environmental Society
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• v.21 no.11
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• pp.21-26
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• 2020

Natural soil is composed of particles of various sizes, and the shear behavior which is a kind of mechanical behavior of the soil is affected by the particle size distribution. In addition, since the natural soil contains a large mixture of coarse and fine grained soil, it is difficult to clearly understand the shear behavior of the soil. Therefore, a ring shear test was conducted on sandy soils that has various particle size distribution in order to identify the effect of the distribution on shear characteristics of soils. At this time, sand and silt were used for coarse and fine grained soils, respectively, to make sandy soils by changing the silt content. Also the water was supplied during the test to confirm shear characteristics of sandy soils with various particle size distributions. The result shows that the shear strength increases as the silt content increases, and the strength decreases as the silt content increases over the sand. Besides, residual shear strength gradually decreases because of the silt content when the water is supplied.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.290-293
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• 1995

This study was designed to investigate the effect of potato lipoxygenase on the change of dough chemical composition including lipid distribution, fatty acid composition, carotenoids content and color value in wheat flour dough. For the study, the potato lipoxygenase was added to wheat flour at a level of $6.5{\times}10\;unit/g$ flour. The addition of potato lipoxygenase to wheat flour dough was found to cause an increase in free lipid content, an effect apparently related to the decrease in linoleic acid content and increase in peroxide value. This phenomena might be due to the enzymatic oxidation of polyunsaturated fatty acid. Also, the bleaching effect of lipoxygenase was observed as the decrease in carotenoids content of wheat flour dough. In comparison of color value, it was shown that redness, yellowness and total color difference$({\delta}E)$ were lower by addition of lipoxygenase.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.1
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• pp.22-37
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• 2013

Content distribution to a large number of concurrent clients stresses both server and network. While the server limitation can be circumvented by deploying server clusters, the network limitation is far less easy to cope with, due to the difficulty in measuring and balancing network load. In this paper, we use two useful network load metrics, the worst link stress (WLS) and the degree of interference (DOI), and formulate the problem as partitioning the clients into disjoint subsets subject to the server capacity constraint so that the WLS and the DOI are reduced for each session and also well balanced across the sessions. We present a network load-aware partition algorithm, which is practicable and effective in achieving the design goals. Through experiments on PlanetLab, we show that the proposed scheme has the remarkable advantages over existing schemes in reducing and balancing the network load. We expect the algorithm and performance metrics can be easily applied to various Internet applications, such as media streaming, multicast group member selection.