• International Journal of Concrete Structures and Materials
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• v.18 no.2E
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• pp.73-77
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• 2006

This paper shows a study of the efficiency of expansive additive and shrinkage reducing admixture in controlling restrained shrinkage cracking of high performance concrete at early age. Free autogenous shrinkage test of $100{\times}100{\times}400mm$ concrete specimens and simulated completely-restrained test with VRTM(variable restraint testing machine) were performed. Creep and autogenous shrinkage of high-performance concrete with and without expansive additive and shrinkage reducing admixture were investigated by experiments that provided data on free autogenous shrinkage and restrained shrinkage. The results showed that the addition of expansive additive and shrinkage reducing admixture effectively reduced autogenous shrinkage and tensile stress in the restrained conditions. Also, it was found that the shrinkage stress was relaxed by 90% in high-performance concrete with and without expansive additive and shrinkage reducing admixtures at early age.

• Journal of the Korea Institute of Building Construction
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• v.7 no.3
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• pp.123-130
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• 2007

This study investigated the fundamental properties and shrinkage properties of high performance concrete with water/binder ratio of 0, 30 and with combination of expansive additive and shrinkage reducing agent. According to the results, the fluidity of high performance concrete showed lower the using method in combination with expansive additive and shrinkage reducing agent than the separately using method of that, so the amount of superplasticizer increased when the adding ratio of expansive additive and shrinkage reducing agent increased. However the air content of concrete increased when used in combination with expansive additive and shrinkage reducing agent, so the amount of AE agent decreased. The compressive strength showed the highest at 5% of expansive additive, and decreased with an increase of the amount of shrinkage reducing agent. Furthermore, in order to reduce the shrinkage of high performance concrete, it was found that the using method in combination with expansive additive and shrinkage reducing agent was more effective than separately using method of that. Autogenous shrinkage was predicted using JCI model. Because JCI model is unable to consider the effect of EA and SRA, correction factor should be added to enhance the accuracy.

• Bulletin of the Korean Mathematical Society
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• v.46 no.2
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• pp.387-400
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• 2009

We establish a new strategy to study the Hyers-Ulam-Rassias stability of the Cauchy and Jensen equations in non-Archimedean normed spaces. We will also show that under some restrictions, every function which satisfies certain inequalities can be approximated by an additive mapping in non-Archimedean normed spaces. Some applications of our results will be exhibited. In particular, we will see that some results about stability and additive mappings in real normed spaces are not valid in non-Archimedean normed spaces.

• Kyungpook Mathematical Journal
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• v.55 no.1
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• pp.41-50
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• 2015

The purpose of this paper is to prove some results which are of independent interest and related to additive maps on ${\sigma}$-prime rings. Further, examples are given to demonstrate that the restrictions imposed on the hypotheses of these results are not superfluous.

• International Journal of Highway Engineering
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• v.15 no.4
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• pp.117-125
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• 2013

PURPOSES : The purpose of this study is to evaluate of field application and laboratory performance of warm-mix asphalt (WMA) according to the dosage rate of organic-based WMA additive. METHODS: Three asphalt mixtures, i.e., hot mix asphalt (HMA), WMA with the dosage rate of 1.5%, WMA with the dosage rate of 1.0%, were sampled from the asphalt plant when the field trial project were constructed. With these mixtures, the laboratory testings were performed to evaluate the linear viscoelastic characteristics and the resistance to moisture, rutting and fatigue damage. RESULTS : From the laboratory test results, it was found that the WMA with the reduced dosage rate of additive would be comparable to HMA and WMA with the original dosage rate in terms of the dynamic modulus, tensile strength ratio, rutting resistance. However, the fatigue reisistance of WMA with the reduced dosage rate was slightly worse but it should be noted that the fatigue performance is necessarily predicted by combining the material properties and pavement structure. CONCLUSIONS: Through the field construction and laboratory testings, the dosage rate of organic-based WMA additive could be reduced from 1.5% to 1.0% without the significant decrease of compactability and laboratory performance. The long-term performance of the constructed pavement will be periodically monitored to support the findings from this study.

• Journal of Technologic Dentistry
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• v.43 no.4
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• pp.153-159
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• 2021

Purpose: The purpose of this study was to assess the fitness of anterior and posterior interim crowns fabricated by three different additive manufacturing technologies. Methods: The working model was digitized, and single crowns (maxillary right central incisor and maxillary right first molar) were designed using computer-aided design software (DentalCad 2.2; exocad). On each abutment, interim crowns (n=60) were fabricated using three types of additive manufacturing technologies. Then, the abutment appearance and internal scan data of the interim crown was obtained using an intraoral scanner. The fitness of the interim crowns were evaluated by using the superimposition of the three-dimensional scan data (Geomagic Control X; 3D Systems). The one-way analysis of variance and Tukey posterior test were used to compare the results among groups (α=0.05). Results: A significant difference was found in the fitness of the interim crowns according to the type of additive manufacturing technology (p<0.05). The posterior interim crown showed smaller root mean square value than the anterior interim crown. Conclusion: Since the fitness of the posterior interim crown produced by three types of additive manufacturing technology were all within clinically acceptable range (<120 ㎛), it can be sufficiently used for the fabrication of interim crowns.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.9
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• pp.1341-1347
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• 2002

An experiment was conducted to determine effects of oral administration of $Diakur^{TM}$ (an additive of glucose and electrolytes for young calves) on growth performance and some physiological responses in male broilers reared in a high temperature. A 2 by 3 factorial arrangement test of 2 temperatures (24 and $36^{\circ}C$) and 3 levels of oral administration of the glucose and electrolytes additive, $Diakur^{TM}$, (0, 150 and 300 mg/day/100 gBW) were applied in the experiment. Male broiler chicks (2 weeks of age) were assigned to six groups and received dietary and temperature treatments for 7 days. The additive of glucose and electrolytes was suspended with water and intubated into crop twice a day (08:00 and 17:00). Oral administration of the additive prevented decreases in food intake and growth rates in broilers due to exposure of the hot environment. Oral administration of the additive also improved a lowered electrolyte ($Na^+$ + $K^+$ - $Cl^-$) balance in plasma, low mitogenic response of blood mononuclear cell and an increase in glucose concentration due to exposure to the high environmental temperature. Oral administration of the additive increased rectal temperature regardless of environmental temperatures. On the other hand, blood pH, $pCO_2$ and $HCO_3$ - concentration, and plasma creatine kinase activity were not affected by the oral administration. The results suggested that oral administration of the glucose and electrolytes additive, $Diakur^{TM}$ during heat stress did not only prevent decrease in growth performance, but also normalized some physiological and immunological responses in male broilers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1292-1297
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• 2009

This study was performed to investigate solubility, dissolution rate and ash content of solid type fuel additive in gasoline and diesel in order to set up manufacturing standards. From the results, the unfiltered impurities were increased when the fuel additive was added on gasoline and diesel. Also, the unfiltered fuel additive was decreased with respect to increasing the pore size of the filter paper. When one gram of the fuel additive was dissolved in one liter of gasoline at room temperature, the best dissolution rate was about 2 hours. But, almost nothing was dissolved in diesel during 72 hours at $20^{\circ}C$ below zero. At the experiment of ash content, the gasoline which the fuel additive was melted in was showing 28 times more ash content than that was not including the fuel additive. Therefore, it seemed that almost all of ash content was caused by the fuel additive.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.679-682
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• 2005

The effects of substituting cement with fiber addition(poly vinyl alcohol), fly ash and Expansive Additive on the control of microcrack and enhanced durability performance of face slab concrete in concrete-faced rockfill dam was studied experimentally The laboratory test results shown that the mixture of fiber containing concrete and of fly ash replacement of concrete to be more effective than expansive additive concrete in the crack control and mechanical performance.

• Journal of the Chungcheong Mathematical Society
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• v.22 no.1
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• pp.101-116
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• 2009

In 1940 S.M. Ulam proposed the famous Ulam stability problem. In 1941 D.H. Hyers solved the well-known Ulam stability problem for additive mappings subject to the Hyers condition on approximately additive mappings. In this paper we improve results for Jensen type mappings and establish new theorems about the Ulam stability of additive and alternative Jensen type mappings.