• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.2
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• pp.145-152
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• 2017

Mixing of molecular grains having different characteristics is very important in many industries such as the food and pharmaceutical industries. With the development of computer simulations, it is common practice to find the optimal mixing conditions through a simulation before the actual mixing task to estimate the proper level of mixing. Accordingly, there has been an increasing need for a mixing index to measure the mix of particles in the simulation process. Mixing indices, which have been widely used so far, can largely be classified into two types: first is the statistical-based mixing index, which is prepared using the sampling method, and the second is the mixing index that is prepared using all the particles. In this paper, we calculated mixing indices in different ways for the data in the course of mixing the particles using the DEM simulation. Additionally, we compared the performance, advantages, and disadvantages of each mixing index. Therefore, I propose a standard that can be used to select an appropriate mixing index.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.3
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• pp.10-31
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• 2021

The mixed-use concept definition, this study reveals, is that the mixing three or more major types of urban uses implements for economical, social and environmental values in our urban space. With this definition the study explores Seoul's mixed-use phenomenon. The quantification method, the study uses, is the relative entropy which calculate the balance of each urban use in a certain area. The relative entropy method, also known as the LUM(land-use mix score), uses three urban-use categories which is derived from the mixed-use concept definition. Hundreds of building-use types in the building regulations are categorized and calculate the LUM of Seoul's legal-status neighborhoods. The result interpreted as the criteria of Seoul's mixed-use phenomenon and categorize mixed land-use status in a certain value: 'non mixed-use' category has a value 0.631 and below, 'unbalanced mixed-use' category has a value between 0.631 and 0.884, 'balanced mixed-use' category has a value between 0.884 and 0.991 and 'complete mixed-use' category has a value 0.991 and over.

• Korean Journal of Breeding Science
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• v.43 no.5
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• pp.442-447
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• 2011

This study was carried out to assess the potential of hypocotyl explants for multiple-propagation by intensive sweetener variety with high yielding in stevia of self-fertilization. Agronomical character of self-fertilization shown a height range 72.0~120.7 cm, branch's 4.9~56.6 in stevia. Selection of high content of Rebaudioside A (RA) from segregating population in mixing variety have a variety, 'DA1' (55.2%) from HPLC analysis. On a developing of multiple-propagation in stevia, hypocotyl explants used to select for reasonable medium under the influence of each plant growth regulators concentrations. In a Mix treatment of plant growth regulators, as Murashige and Skoog medium with 1.5 mg/L BA and 0.5 mg/L Kinetin showed the most favorable. We got the multiple-propagation of 30 shoots from one inoculated hypocotyl explants as the result of these bases. Rooting induced superbly on MS medium with 0.1 mg/L IBA with inoculated shoots. All of the rooting plants were adapted to a normal seedling. This method of multi-propagation is used effectively in Rebaudioside A productivity elevation.

• Journal of the Korea Institute of Building Construction
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• v.19 no.4
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• pp.307-312
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• 2019

Sludge generated in the production of ready-mixed concrete is classified as waste and processed at a high cost. In particular, small and medium-sized ready-mix manufacturer are burdened with such costs, and some companies are illegally processing them. Therefore, the purpose of this study is to suggest a method for recycled remicon sludge as a concrete block composition. When the remicon sludge is simply dried, the residual chemical admixture and ettringitee contained in the sludge are present, so that the compressive strength of the concrete block and the compressive strength after freezing and thawing are largely deteriorated to meet the quality standards of the concrete shore and retaining wall block It was not possible to do. As a method for satisfying the physical performance, it was found that the remicon sludge was calcined at a high temperature of about $900^{\circ}C$. to decompose ettringite and residual chemical admixture and then used it.

• Korean Journal of Pharmacognosy
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• v.52 no.3
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• pp.192-201
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• 2021

Dangguisu-san (DGSS) is widely known traditional herbal medicinal formula in Korea for treatment of traumatic injury by traffic accident, ecchymosis, abdominal distension and anti-thrombosis of blood. This study was conducted to develop the simultaneous analyze method using high performance liquid chromatography (HPLC) and examine the effect of anti-inflammatory activity of DGSS-dry extract (DGSS-DE) and DGSS-mix extract powder (DGSS-MEP). Physicochemical characteristics of DGSS-DE and DGSS-MEP showed that there is no significant difference in pH, titratable acidity, total soluble solid content and browning degree except for color value (L, a, b). 15 functional constituents of DGSS were identified and the correlation coefficient values of DGSS-DE and DGSS-MEP were conformed 0.950. Also, DGSS-DE and DGSS-MEP significantly decreased the secretion of nitric oxide (NO), prostaglandin E₂ (PGE₂), interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) through inhibited expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), IL-1β, IL-6, and TNF-α. From these result, DGSS-MEP showed similar chemical composition and anti-inflammatory effect to DGSS-DE. Therefore, DGSS-DE and DGSS-MEP may be useful as potential source of drug to prevent inflammation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.3
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• pp.237-246
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• 2021

With climate change, debris flow has been increasing due to the collapse and erosion of shallow slopes caused by extreme rainfall. It is preferred to an economical and eco-friendly method rather than reinforcement of soil slopes with the earth anchor or nailing method. In this study, a soil improvement agent was developed by utilizing insitu soil, leaf mold, and used harbal medicine to help sufficient vegetation. In addition, to prevent surface erosion, shear strength of the soil was increased by using micro cement and hemihydrate gypsum as additives. The optimum mix ratio of the mixture is determined by increasing the shear strength by checking the erosion progress of the ground surface layer due to rainfall through an laboratory test. The safety factor of soil slope has been improved on the slope surface reinforced by the improvement agent, and the strength of erosion has been increased, making it efficient to cope with heavy rain during wet season.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.1
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• pp.58-65
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• 2021

In this study, as a method to increase the recycling of circulating fluidized bed combustion ash(CFBCA), CFBCA was utilized to produce autoclave aerated concrete product since CFBCA contains quicklime and calcium sulfate components that are required for the manufacture of autoclave aerated concrete. Successful achievement of such objective will bring cost reduction with high value addition, saving of natural resources, and the reduction of environmental load. Various mixing designs were designed to evaluate the properties of autoclave aerated concrete made of CFBCA. Based on series of experimental program, prototypes mix design for factory manufacturing was obtained. According to the experimental results, it was confirmed that gypsum can be replaced with CFBCA through the method of pre-treating the CFBCA as a slurry. It was possible to produce competitive autoclave aerated concrete products using CFBCA.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.5
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• pp.69-73
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• 2022

In this paper, we propose a new method for measuring fine dust through a LoG(Laplacian of Gaussian)-based edge detection technique. CCTV-based images in a video are collected for fine dust measurement, and image ranges are designated through RoI(Region of Interest). After clustering by applying the GMM(Gaussian Mix Model) to the specified area, we detect edge through the LoG algorithm and measure the detected edge strength. The concentration of fine dust is determined based on the measured intensity data of the edge. In this paper, we propose algorithm as the effectiveness of experiment. As a result of collecting and applying CCTV image in the video installed around the laboratory of this school for a month from June to July, the measured result value was proved through this experiment to be sufficient to calculate the concentration and range of fine dust.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4A
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• pp.795-808
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• 2006

In this paper, an analytical method which can predict the occurrence of plastic shrinkage cracking on concrete slabs with sequential placement is proposed on the basis of the numerical model introduced in the previous study. The influence of many design variables on plastic shrinkage cracking such as the number of layers and the time interval between layers is quantitatively analyzed through parametric studies using the analytical method. In advance, two equations are introduced to take into account the effect of sequential placement on the plastic shrinkage cracking of concrete slab; The first one is to calculate the time at which the surface of concrete slab begins to dry, and the second one is to determine the critical time interval to prevent the surface drying of previously placed concrete layers. The timing of curing and the sequence of concrete placement, which are important for the prevention of plastic shrinkage cracking, can be effectively planned using the introduced both equations without any rigorous analysis.

• Structural Engineering and Mechanics
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• v.87 no.3
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• pp.221-229
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• 2023

Urbanization and industrialization have significantly increased the amount of solid waste produced in recent decades, posing considerable disposal problems and environmental burdens. The practice of waste utilization in concrete has gained popularity among construction practitioners and researchers for the efficient use of resources and the transition to the circular economy in construction. This study employed Lytag aggregate, an environmentally friendly pulverized fuel ash-based lightweight aggregate, as a substitute for natural coarse aggregate. At the same time, fly ash, an industrial by-product, was used as a partial substitute for cement. Concrete mix M20 was experimented with using fly ash and Lytag lightweight aggregate. The percentages of fly ash that make up the replacements were 5%, 10%, 15%, 20%, and 25%. The Compressive Strength (CS), Split Tensile Strength (STS), and deflection were discovered at these percentages after 56 days of testing. The concrete cube, cylinder, and beam specimens were examined in the explorations, as mentioned earlier. The results indicate that a 10% substitution of cement with fly ash and a replacement of coarse aggregate with Lytag lightweight aggregate produced concrete that performed well in terms of mechanical properties and deflection. The cementitious composites have varying characteristics as the environment changes. Therefore, understanding their mechanical properties are crucial for safety reasons. CS, STS, and deflection are the essential property of concrete. Machine learning (ML) approaches have been necessary to predict the CS of concrete. The Artificial Fish Swarm Optimization (AFSO), Particle Swarm Optimization (PSO), and Harmony Search (HS) algorithms were investigated for the prediction of outcomes. This work deftly explains the tremendous AFSO technique, which achieves the precise ideal values of the weights in the model to crown the mathematical modeling technique. This has been proved by the minimum, maximum, and sample median, and the first and third quartiles were used as the basis for a boxplot through the standardized method of showing the dataset. It graphically displays the quantitative value distribution of a field. The correlation matrix and confidence interval were represented graphically using the corrupt method.