• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.2
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• pp.89-96
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• 2011

In this study, increasing the range of replacement rate of FA with concrete properties were analyzed to provide basic data of FA replacement 0-40 % and curing temperature $5-35^{\circ}C$ range. As a result of the increased fluidity in proportion to the increase in FA, but decreased air. Setting time delayed at replacement rate increases and low temperature, simple insulation temperature history of the FA up to 40 % replacement rate increases the maximum temperature was low $8^{\circ}C$, the highest temperature reaching time delay of 13 hours. FA replacement up stream of the curing temperature, compressive strength compared to the higher plane, it was found that improved strength development. In carbonation tests with increasing the replacement ratio of FA carbonation depth was increased. Therefore, continued research on carbonation measures was to be necessary.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.5
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• pp.37-42
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• 2004

Shallow $p^{＋}$-n junctions were formed by preamorphization, low-energy ion implantation and dual-step annealing processes. Germanium ions were implanted into silicon substrates for preamorphization. The dopant implantation was performed into the preamorphized and non-preamorphized substrates using B $F_2$2 ions. Rapid thermal anneal (RTA) and furnace anneal (FA) were employed for dopant activation and damage removal. Samples were annealed by one of the following four methods; RTA(75$0^{\circ}C$/10s)＋Ft FA＋RTA(75$0^{\circ}C$/10s), RTA(100$0^{\circ}C$/10s)＋FA, FA＋The Ge Preamorphized sample exhibited a shallower junction depth than the non-preamorphized sample. When the employed RTA temperature was 100$0^{\circ}C$, FA＋RTA annealing sequence exhibited better junction characteristics than RTA＋FA thermal cycle from the viewpoint of junction depth, sheet resistance, $R_{s}$$.$ $x_{j}$, and leakage current.t.

• Geosystem Engineering
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• v.21 no.5
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• pp.243-250
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• 2018

This study investigated nitrite ($NO_2{^-}$) accumulation due to FA (Free Ammonia: $NH_3$) inhibition in an anaerobic-aerobic-anoxic (AOA) process reactor to mainly treat wastewater containing 302-610 mg/L of $NH_3/NH_4{^+}-N$. Based on an experimental operation focusing on the nitrification, it was observed that $NO_2{^-}$ was accumulated in the aerobic nitrification zone as pH increased, due to inhibition of $NO_2{^-}$ conversion to $NO_3{^-}$ by FA. This result implied FA inhibition to NOB ($NO_2{^-}$-Oxidizing Bacteria) for converting $NO_2{^-}$ to $NO_3{^-}$. The objective of this study is to develop a feasible monitoring procedure for early detection of the FA inhibition toward $NO_2{^-}$ accumulation and poor nitrification. Thus, in order to rapidly assess FA concentrations, an $NH_3$ probe was utilized to measure $NH_3$ concentrations together with applying a simple model prediction using the measured $NH_4{^+}$ concentrations, the Henry's law constant of $NH_3$ and measured pH. The predictive model $NH_3$ levels were verified by a good correlation (89%) with the corresponding measured data, but the model prediction underestimated FA concentrations at less than 7.4 and a little overestimated at pH above 7.5. Interestingly, accumulated $NO_2{^-}$ levels were roughly correlated with FA levels that were observed at delayed time points. This reflects the detected FA levels can be good indicators of $NO_2{^-}$ levels with some delayed time. $NO_2{^-}$ accumulation started at measured FA concentrations of higher than approximately 3 mg/L and ceased below that FA level.

• Journal of Microbiology and Biotechnology
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• v.32 no.3
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• pp.387-395
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• 2022

Deciphering the metabolites of human diseases is an important objective of biomedical research. Here, we aimed to capture the core metabolites of Fanconi anemia (FA) using the bioinformatics method of a multi-omics composite network. Based on the assumption that metabolite levels can directly mirror the physiological state of the human body, we used a multi-omics composite network that integrates six types of interactions in humans (gene-gene, disease phenotype-phenotype, disease-related metabolite-metabolite, gene-phenotype, gene-metabolite, and metabolite-phenotype) to procure the core metabolites of FA. This method is applicable in predicting and prioritizing disease candidate metabolites and is effective in a network without known disease metabolites. In this report, we first singled out the differentially expressed genes upon different groups that were related with FA and then constructed the multi-omics composite network of FA by integrating the aforementioned six networks. Ultimately, we utilized random walk with restart (RWR) to screen the prioritized candidate metabolites of FA, and meanwhile the co-expression gene network of FA was also obtained. As a result, the top 5 metabolites of FA were tenormin (TN), guanosine 5'-triphosphate, guanosine 5'-diphosphate, triphosadenine (DCF) and adenosine 5'-diphosphate, all of which were reported to have a direct or indirect relationship with FA. Furthermore, the top 5 co-expressed genes were CASP3, BCL2, HSPD1, RAF1 and MMP9. By prioritizing the metabolites, the multi-omics composite network may provide us with additional indicators closely linked to FA.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.5
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• pp.95-102
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• 2022

Recently, there has been a growing interest in reducing greenhouse gases in all industrial fields. In the construction industry, studies have been conducted for the use of high-volume fly ash concrete to replace cement with fly ash. Quantitative measurements of cement hydration and fly ash reactivity enable a clear understanding of the strength development mechanism of high-volume fly ash concrete. It is very difficult to describe the reactivity in a simple way because the hydration and pozzolanic reactions of cement paste containing fly ash are very complex and the composition of the hydration product cannot be accurately determined. This study investigated the hydration and mechanical properties of high volume fly ash (HVFA) cement according to the substitution rate of fly ash (FA). The hydration degree of cement and the reactivity of FA were evaluated through the selective dissolution method and the non-evaporable water content of the paste according to age. In addition, compressive strength was measured using HVFA mortar specimens according to age. As a result of the experiment, as the substitution rate of fly ash increased, the hydration degree of cement increased, but the reactivity of FA decreased.

• Advances in concrete construction
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• v.12 no.5
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• pp.429-437
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• 2021

In the era of building engineering the intensification of Self Compacting Concrete (SCC) is world-shattering magnetism. It has lot of rewards over ordinary concrete i.e., enrichment in production, cutback in manpower, brilliant retort to load and vibration along with improved durability. In the present study, the mechanical strength of CM-2 (SCC containing 10% of rice husk ash (RHA) as cement replacement and 600 grams of glass fibers per cubic meter) was investigated at various dosages of cement replacement by fly ash (FA) and GGBS. A total of 17 SCC mixtures including two control SCC mixtures (CM-1 and CM-2) were developed for investigating fresh and hardened properties in which, ten ternary cementitious blends of SCC by blending OPC+RHA+FA, OPC+RHA+GGBS and five quaternary cementitious blends (OPC+RHA+FA+GGBS) at different replacement dosages of FA and GGBS were developed with reference to CM-2. For constant water-cement ratio (0.42) and dosage of SP (2.5%), the addition of glass fibers (600 grams/m³) in CM-1 i.e., CM-2 shows lower workability but higher mechanical strength. While fly ash based ternary blends (OPC+RHA+FA) show better workability but lower mechanical strength as FA content increases in comparison to GGBS based ternary blends (OPC+RHA+GGBS) on increasing GGBS content. The pattern for mixtures appeared to exhibit higher workablity as that of the concentration of FA+GGBS rises in quaternary blends (OPC+RHA+FA+GGBS). A decrease in compressive strength at 7-days was noticed with an increase in the percentage of FA and GGBS as cement replacement in ternary and quaternary blended mixtures with respect to CM-2. The highest 28-days compressive strength (41.92 MPa) was observed for mix QM-3 and the lowest (33.18 MPa) for mix QM-5.

• Korean Journal of Acupuncture
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• v.40 no.2
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• pp.33-43
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• 2023

Objectives : Floating acupuncture (FA) is a kind of newly developed acupuncture technique that contains its own apparatus. The technique has unique points that the body of the acupuncture needle stays intradermal space and manipulation is performed by shaking the needle horizontally; after manipulation, part of the needle remained in the intradermal space for 2~3 days. FA is not a common acupuncture methodology while various clinical study claims its efficacy on musculoskeletal disorders. In this study, the authors aimed to enhance the use of FA by comparing related theories. Methods : The authors reviewed classics, books, and articles related to FA, Meridian Muscle (MM), Myofascial Pain Syndrome (MPS), and Wrist-Ankle Acupuncture (WAA), and compared its characteristics by related theory, related symptoms, apparatus, and performing procedures. Results : FA was related and had various common parts with MM, MPS, and WAA, however, there were unique parts in the manipulation, apparatus, and stimulation location. FA is based on MM and MPS which pointing 'ashi points' or 'trigger points' as a treating target while FA does not stimulate the points directly. FA also targets subcutaneous space by inserting the needle horizontally as WAA does, while FA remains the needle handle part in the subcutaneous area for 2~3 days for more stimulation. Conclusions : FA has a unique manipulation procedure and potential benefit for musculoskeletal disorders despite the crude theological base written by Fu himself. Thus, developing a new explanation and patient-friendly methodology/apparatus is required for further down-to-earth studies.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4B
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• pp.427-432
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• 2006

The effects of free ammonia (FA) concentration and temperature on nitrite accumulation were studied. To estimate the most effective ammonium oxidation and nitrite build-up condition, nitrification tests were conducted in batch conditions at various FA concentrations, and at different ammonium concentration and temperature. The activation energies of ammonium oxidizer were 81.7 KJ/mol below $20^{\circ}C$, and 32.5 KJ/mol over $20^{\circ}C$, while that of nitrite oxidizer was 35.5 KJ/mol irrespective of temperature variations. The results of nitrification tests conducted at different FA concentrations and temperatures showed that temperature strongly affects nitrite accumulation, while effects due to FA concentrations were found negligible.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.690-700
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• 2012

The experiment was conducted by in vitro fermentation and bacterial community analysis to investigate the reduction of odorous compounds in response to the use of feed additives (FA) during carbohydrate overload in growing pigs. Soluble starch at 1% (control) and various FA at 0.1% Ginseng meal (FA1); Persimmon leaf (FA2); Gingko nut (FA3) and Oregano lippia (FA4) were added to fecal slurry and incubated anaerobically for 12 and 24 h. In vitro parameters and microbial diversity of the dominant bacteria following fermentation were analyzed using Denaturing Gradient Gel Electrophoresis (DGGE), band cloning and sequencing of the V3 region. Results showed that total gas production increased with the advancement of incubation (p<0.05). pH values of FAs and control groups were decreased except the FA4 group which increased somewhat from 12 to 24 h (p<0.05). Ammonia nitrogen ($NH_3$-N) and $H_2S$ gas concentrations were comparatively lower in both stages in FA4 treatment than in the other groups (p<0.05). Hence, $NH_3$-N concentrations in liquid phases were increased (p<0.05) from 12 to 24 h, but the trend was lowest in FA4 than in the other groups at both stages. The total VFA production was comparatively lower and butyrate levels were moderate in FA4 group than in the the other groups during both stages (p<0.05). Indirect odor-reducing compounds such as $NO_2$, $NO_3$ and $SO_4$ concentrations were higher in the FA4 and FA3 than in the other groups at 24 h (p<0.05). After fermentation, ten dominant bands appeared, six of which appeared in all samples and four in only the FA4 treated group. The total number of DGGE bands and diversity was higher in the FA4-group compared to other groups. Additionally, similarity indices were lowest (71%) in the FA4, which represented a different bacterial community compared with the other groups. These findings indicate that $NH_3$-N, $H_2S$ and VFA production was minimal, and pH was also better in the FA4 group than in the other groups. Furthermore, the conversion of odor-reducing indirect compounds or their intermediates was higher in the FA4 group in compared to the other groups. FA4 group generated less odorous products and more indirect products by in vitro fermentation at 24 h, and their microbial pattern appeared to differ from that of the other groups. These findings suggest that this particular FA could change the microbial population, which may have a beneficial effect on odor reduction. It is recommended that the oregano lippia may be supplied to growing pigs as FA along with excess carbohydrate sources to reduce the production of odorous compounds.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.1
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• pp.131-138
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• 2010

This research intends to analyze the basic characteristics of cements(hereinafter "CC") with affordable price and particle distribution effective as hydration heat face which are discharged at the outlet of smashing process of ordinary portland cement(hereinafter "OPC") manufacturing process such as fluidity, rigidity, temporary insulation temperature increase amount etc to review the potential of developing "CC" to 3 ingredients low heat cement that substitutes fly ash and blast furnace slag(hereinafter "BS"). As a result of experiment, fluidity tended to decrease with increase in CC substitution rate, and increase with increase in FA+BS substitution rate. Air amount tended to slightly decrease with increase in CC substitution rate, and decrease with increase in FA+BS substitution rate. Condensation characteristics were such that condensation time was delayed with increase in CC and FA+BS substitution rate. As for the temperature rising amount by temporary insulation, peak temperature decreased with increase in CC substitution rate and increase in FA+BS substitution rate in general, and thereafter, temperature tended to decrease slowly. Compressive strength decreased with increase in CC and FA+BS substitution rate, and as aging goes on, long term strength was equivalent to plain or higher. By and large, when FA+BS was substituted to CC, fluidity and air amount tended to decrease, but hydration heat face showed good reduction effects, suggesting possibility of development to 3 ingredients low heat cement.