• Advances in concrete construction
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• v.6 no.4
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• pp.323-344
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• 2018

The study herein reports the impact of Steel Fiber (SF) and Ground Granulated Blast Furnaces slag (GGBFS) content on the fresh and hardened properties of fly ash (FA) based Self-Compacting Geopolymer Concrete (SCGC). Two series of self-compacting geopolymer concrete (SCGC) were formulated with a constant binder content of $450kg/m^3$ and at an alkaline-to-binder (a/b) ratio of 0.50. Fly ash (FA) was substituted with GGBFS with the replacement levels being 0%, 25%, 50%, 75%, and 100% by weight in each SCGC series. Steel fiber (SF) wasn't employed in the assembly of the initial concrete series whereas, within the second concrete series, an SF combination was achieved by a constant additional level of 1% by volume. Fresh properties of mixtures were through an experiment investigated in terms of slump flow diameter, T50 slump flow time, V-funnel flow time, and L-box height ratio. Moreover, the mechanical performance of the SCGCs was evaluated in terms of compressive strength, splitting tensile strength, and fracture toughness. Furthermore, a statistical analysis was applied in order to judge the importance of the experimental parameters, like GGBFS and SF contents. The experimental results indicated that the incorporation of SF had no vital impact on the fresh characteristics of the SCGC mixtures whereas GGBFS aggravated them. However, the incorporation of GGBFS was considerably improved the mechanical properties of SCGCs. Moreover, the incorporation of SF with the total different quantity of GGBFS replacement has considerably increased the mechanical properties of SCGCs, by close to (65%) for the splitting strength and (200%) for compressive strength.

• Tuberculosis and Respiratory Diseases
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• v.67 no.4
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• pp.364-368
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• 2009

Bronchiolitis interstitial pneumonitis (BIP), an unclassified and newly described interstitial pneumonia, has a combined feature of prominent bronchiolitis, interstitial inflammation, and fibrosis. It is distinct from bronchiolitis obliterans or bronchiolitis obliterans organizing pneumonia (BOOP). BIP has a better prognosis than common cases of interstitial pneumonia. However, BIP has a poorer prognosis than BOOP. BIP's response to corticosteroids is not as successful as BOOP's response to this treatment. We encountered the case of a 31-year-old woman with BIP with an initial presentation of dyspnea and a cough that had lasted for 3 months. The patient's chest CT scan demonstrated patchy ground glass opacities and multiple ill-defined centrilobular nodules in both lungs, suggesting military tuberculosis or nontuberculous mycobacterial infection. A video-assisted thoracoscopic lung biopsy resulted in the diagnosis of BIP. Clinical symptoms, pulmonary lesions, and pulmonary function tests were improved after oral glucocorticoid therapy.

• Korean Journal of Applied Biomechanics
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• v.25 no.2
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• pp.141-147
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• 2015

Objective : This study aimed to understand how increased heart rates at the time of drop landing during a step test would affect biomechanical variables of the lower extremity limbs. Background : Ballet performers do more than 200 landings in a daily training. This training raises the heart rate and the fatigability of the lower extremity limbs. Ballet performance high heart rate can trigger lower extremity limb injury. Method : We instructed eight female ballet dancers with no instability in their ankle joints(mean ${\pm}$ SD: age, $20.7{\pm}0.7yr$; body mass index, $19.5{\pm}1.2kg/m^2$, career duration, $8.7{\pm}2.0yr$) to perform the drop landing under the following conditions: rest, 60% heart rate reserve (HRR) and 80% HRR. Results : First, the study confirmed that the increased heart rates of the female ballet dancers did not affect the working ranges of the knee joints during drop landing but only increased angular speeds, which was considered a negative shock-absorption strategy. Second, 80% HRR, which was increased through the step tests, led to severe fatigue among the female ballet dancers, which made them unable to perform a lower extremity limb-neutral position. Hence, their drop landing was unstable, with increased introversion and extroversion moments. Third, we observed that the increasing 80% HRR failed to help the dancers effectively control ground reaction forces but improved the muscular activities of the rectus femoris and vastus medialis oblique muscles. Fourth, the increasing heart rates were positively related to the muscular activities of the vastus medialis oblique and rectus femoris muscles, and the extroversion and introversion moments. Conclusion/Application : Our results prove that increased HRR during a step test negatively affects the biomechanical variables of the lower extremity limbs at the time of drop landing.

• Advanced Composite Materials
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• v.18 no.4
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• pp.315-326
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• 2009

PCC (precipitated calcium carbonate) and ground calcium carbonate have been widely used in alkaline papermaking. Unfortunately, although increasing filler level in papers can improve the paper properties such as brightness, opacity, stiffness gloss, smoothness, porosity, and printability, as well as decrease cost, some strength of the paper is negatively affected. In this research, needle-like aragonite was synthesized using $Ca(OH)_2$ and $CO_2$ as reactants in the presence of $MgCl_2$ and characterized with scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The physical and optical properties of the paper handsheets containing these needle-like aragonite fillers were evaluated. Results indicated that tensile strength, Z-direction tensile strength and folding endurance of the paper were improved by the needle-like aragonite crystals compared to the paper using commercial PCC (precipitated calcium carbonate) as filler. The stiffness of the paper handsheet on the machine direction was increased, but no evident difference in the cross direction was found. The improvement of paper strength mainly resulted from the twining effect between the aragonite whiskers and paper fibers. The optical properties of the paper were slightly decreased with the use of the needle-like aragonites compared to commercial PCC. These results suggest that paper cost can be decreased by increasing the content of needle-like aragonite filler while paper strength will not be decreased compared to PCC filler.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.1
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• pp.62-69
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• 2000

The purpose of this study is to evaluate naturalness of botanical garden pre- and post-assessed according to the Hemeroby Index in the case study of Daegok Botanical Garden. The results of the study are as follows. 1) The results of the site analysis according to the Hemeroby Index before development have been appeared that highest of poly/meta-hemeroby is 45.8% and the next of meso-hemeroby is 28.3%. 2) After development, the highest of meso-hemeroby is 53.6% and the next of $\alpha$ -euhemeroby is 28.3%. Generally, it is considered that the naturalness according to Hemeroby Indx was lasted higher after development than that before development. 3) Both a-hemeroby and oligo-hemeroby are not appeared before and after development. $\alpha$ -euhemeroby and meta-hemeroby are not appeared before development, but htey increased as much as 16.8% and 6.8% after development. Most of all, the increase of meta-hemeroby after development results from the increase of the artificial facilities (e.g. pavements, buildings and so on). 4) Specially, through the modification of play ground, park lot, pavement classified to meta-hemeroby, it is considered that the Hemeroby Index would be improved. 5) Compared with existing naturalness grade of green space, it has merits to apply Hemeroby Index, especially as a menas of distinguised naturalness assessment in various land use pattern. But there is no clear evidence that limits the minimum size that could be applied with Hemeroby Index. So, we must discuss whether it was useful to apply this standard to such a small specific space as the site of this study.

• Spatial Information Research
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• v.10 no.3
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• pp.469-480
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• 2002

Nowadays, digital maps of 1:5,000 scale are used to plan and review far road alignment design. However, the updating and modifying period of digital maps is not so harmonious as topographical changes caused by rapid developments can be reflected in digital maps, the different areas between real surface and digital map can be found easily. This research is aimed to suggest that the use of high resolution satellite image is effective way to get latest topographical information for road alignment design about wide region. IKONOS satellite images were geometrically corrected, and the road alignment data previously designed by traditional procedure were overlapped on the satellite images. As a result, the satellite image maps clearly described wrong road alignment, and modification of road alignment could be accomplished adequately By these procedures, road alignment design was Improved in quality, and could be reasonable and economic design to prevent modification that would be happened in the next step of practical plan. For the geometric correction method of IKONOS images, Thin Plate Spline(TPS) transformation with large number of ground control points, as well as ortho rectification, was effective.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.3
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• pp.239-246
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• 2014

High volume slag concrete is attracting new attention and are thought to have promising potential for industrial applications, partly due to the climate debate, but especially due to their very low heat of hydration and their good durability in chemically aggressive environments. However, High volume slag concretes tend to have slower strength development especially. In this study, the effect of anhydrite ($CaSO_4$) on the mechanical and durability performance of high volume slag concrete were investigated. The main variables were anhydrite contents (0, 4, 6, 8, 10%). Test results show that 4~8% anhydrite concrete have improved engineering properties (hydration, compressive strength, shrinkage, creep, carbonation) as control concrete at early ages.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.198-203
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• 1997

The ground persimmon puree was treated with two kinds of commercial polysaccharide hydrolyzing enzymes (Viscozyme and Celluclast) in order to study their effects on the extraction yield, viscosity, color, titratable acidity and sugars. Hydrolysis with Viscozyme which has enzymatic activity of arabinase, cellulase, xylanase, hemicellulase and ${\beta}-glucanase$ significantly increased the extraction yield, L-value and reducing sugar and decreased in viscosity by treatment for 10 min at $50^{\circ}C$. The extraction yield of the juice was increased from 42.7% to 80% by Viscozyme while the Celluclast to 73.3%. On the other hand, the sensory properties of persimmon-like flavor, scarlet and orange color were greatly improved for the juice hydrolyzed with Viscozyme for 60 min.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.1
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• pp.1-10
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• 2011

Generally, the tire curing process is the process in which the sulfur is added and subsequently the tire is heated to give the tire elasticity. In this process, all kinds of the chemicals in the tire are emitted with a lot of heat. The chemical fume and heat aggravate the work environment. To solve this problem, 92 local exhaust ventilators and 8 gravity ventilators were used, but not satisfactory yet. Preliminary survey showed that the temperatures in the process were very high: 30.3, 32.9 and $37.2^{\circ}C$ at 2, 4 and 6m above the ground level, respectively in the winter (outside temperature was $2^{\circ}C$). It can be imagined that the process is severely hot in the summer time. The higher temperature distribution in the higher space tells us that the hot plume could not be removed with the existing ventilation systems. Therefore, in this study, some alternative ventilation systems were designed. The partitions were used to contain the hot plume to increase the capture efficiency. The gravity ventilators were newly designed to improve the extraction efficiency of hot fume. To satisfy the balance of pressure in the curing process, some supply air system was introduced by renewing the existing air conditioning system. Many alternative solutions were evaluated by using computational fluid dynamics modelling. The best and applicable solution was selected and the existing ventilation system was modified. After implementing the new ventilation system, the hot environment was much improved. The temperature reduction in the curing process was about $6.4^{\circ}C$.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.558-564
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• 2010

Cleaning up the landfill soil by phytoremediation in association with biomass production and utilization of biosolid as a soil amendment will be an attractive green technology. In order to examine this integrated green technology, in the current study of pot trial, heavy metal removal rate and biomass production were determined following cultivation of three different plant species in the landfill soil incorporated with biosolid at two different levels (25 ton $ha^{-1}$ and 50 ton $ha^{-1}$). Among the three plant species including Indian mustard (Brassica juncea), giant sunflower (Helianthus giganteus. L), and giant cane (Arundo donax. L), sunflower appeared to produce the largest biomass yield (19.2 ton $ha^{-1}$) and the produced amounts were magnificently increased with biosolid treatment compared to the control (no biosoild treatment). The increased production associated with biosolid treatment was common for other plant species and this was attributed to the biosolid originated nutrients as well as the improved soil physical properties due to the organic matter from biosolid. The elevated heavy metals in soil which was originated from the incorporated biosolid were Cu and Zn. Based on the phytoavailable amount of heavy metals from biosolid, the removed amount by plant shoots were 95% and 165% for Cu and Zn, respectively, when sunflower was grown. This indicated that mitigation of heavy metal accumulation in soils achieved by the removal of metal through sunflower cultivation enables the successive treatment of biosolid to soils. Moreover, sunflower showed heavy metal stabilization ability in the rhizosphere resulting in alleviation of metal release to ground water.