• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.399-402
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• 2005

In ultra-high strength SFRCC(Steel Fiber Reinforced Cementious Composites), much silica fume are used to improve strength, flowability and durability. Silica fume have merits of filling the voids, enhancement of reheological chracteristics, production of secondary hydrates by pozzolanic reaction in reactive powder concretes. However silica fume has been imported in high-cost in domestic industry, we need to investigate replaceable material in stead of silica fume in a view of economy Therefore, in this paper, in order to investigate replacement of silica fume in ultra-high strength SFRCC we used the granulate blast-furnce slag with finess 4000, 6000, 8000. As a results, we have evaluated that the bigger the finess the more increase compressive strength of ultra-high strength SFRCC using the blast-furnce slag and there was no problem from the viewpoint of flowability and compressive strength when we use blast-furnce $50\%$ with replacement ratio of silica fume

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.10-11
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• 2021

As concrete is used in many construction works, the use of aggregates is increasing. However, supply and demand of high-quality aggregates has become difficult recently, and although circular aggregates that recycle construction waste are used, the performance of concrete, such as liquidity and strength, are being reduced due to defective aggregates. As a result, quality tests such as sieve analysis test are conducted, but a lot of waste occurs such as time and manpower. To solve this problem, this study was conducted to measure the assembly rate of fine aggregate, which accounts for about 35% of the concrete volume, using Deep Learning.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.721-725
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• 2001

The main reason for applying pulverizer classifier-rotary type in fossil power plant is boiler high efficiency and energy saving movement in the government. This study intends to analyze the boiler efficiency through the pulverizer classifier-rotary type improvement in thermal power plant and makes its comparison to that of the used fixed type.

• Textile Coloration and Finishing
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• v.23 no.4
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• pp.233-240
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• 2011

A fineness range of 150 Nm-170 Nm has recently been applied to produce much finer wool products, so that processing techniques for the wool fabrics have been developed very rapidly. However, the worsted wool-like technique using polyester fiber has not been still implemented in general processing technique. Therefore, this research is to develop materials of side-by-side type with high finess, high shrinkage and stretchability. The mechanical properties of the produced fabrics were analyzed and the fundamental information were obtained for the new worsted wool-like products. The physical properties of a latent crimped yarns of side-by-side type with stretch function are analyzed. Also the mechanical properties of five kinds of fabrics are analyzed, which are produced with non-circular shape(+type) warp yarns of a twist of 1000(T/M) and with two kinds of latent weft yarns of a twist of 1000 T/M and DTY respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.303-308
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• 2001

Recently, concrete structures have become larger and higher and are demanding high performance concrete with lower heat to prevent thermal cracking, far greater workability, high strength and durability, Application of low heat portland(Type IV) cement for the high performance concrete is the best solution to satisfied those requirements. Here are explained the effect on the properties of high flowing concrete using low heat portland cement by material and mixing variations. Variables for sensitivity test were selected items like finess modulus of aggregates, particle size of limestone powder, unit water, superplasticizer, viscosity agent and concrete temperature. The results of this study were be applied to slurry wall of #215 and #216 of underground LNG tank in Inchon.

• Journal of the Korean Home Economics Association
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• v.33 no.1
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• pp.203-210
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• 1995

The purpose of this study was to investigate the weights of clothing that middle school girl students are wearing and ghow athe students evaluate their comfort sensations for the state-of-clothing and classroom conditions. The results obtained were as follows. 1. Average total weights of clothing of each month were 795.5g/m2 for May(23.4$^{\circ}C$), 539-590.6g/m2(26.0-31.2$^{\circ}C$) from June to August, 723.6g/m2 for September(25.6$^{\circ}C$) and 980.2g/m2 for October(24.$0^{\circ}C$). 2. Total weight was changed markedly from May to June and from september to October. The change was mainly by tops. Not much change was observed for the bottoms due to the fact that students were blue jeans irrespect of the environmental conditions. 3. Not significant relationship was observed between clothing weights adn comfort sensations. When the classroom temperature was 23.4$^{\circ}C$, more than 50% of the students answered comfortable. 4. Negative correlation was observed between amount of bottoms weight and Rohrer Index; in other words, fat students were less bottoms such as pants of skirts. 5. Negative correlation was observed between physical finess and amount of under shirts at the month of May, June and October; students with igher physical fitness scores wear less under wear when the environmental temperature changes.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.18 no.1
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• pp.35-38
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• 1982

Ship hull Vibration is caused by troubling measure instruments installed in the ship, fatigue of the hull girder. Vibration has been studied by the View point of anti-Vibration. However, the theoretical calculation values of the Vibration analysis were not obtained accurately. Therfore, in this paper, Vibration analysis were made on the two (cylinder form, ship form) of ship hull girder by the transfer matrix method. The super-structure length was determined to be 0, 20, 40, 60, 80, 100, percentage of the ship's length from the stern. The results of analysis by the transfer matrix method are as follow. 1. Natural frequency may be determined by the order of node numbers and superstructure length. 2. Natural frequency inereased when the ship form is a finess and increasing ratio followed by high order of node numbers.

• Korean journal of food and cookery science
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• v.8 no.2
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• pp.83-93
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• 1992

This dissertation was aimed to study the stability of egg foams and the quality of rice yackwa added with egg foams. Because of the difference of protein composion between rice flour and wheat flour, yackwa made from rice powder turned out to be harder and less raised. Egg foams were added to the rice flour to help raise the dough to a great extent and make it softer when frying. The smaples were prepared differently: in the finess of rice flour (100, 140 mesh), the kinds of egg foams (whole egg, egg white), and the content of egg foams (40 g, 60 g), respectively. The stability of egg foams was determined by an Optical microscope, the hardness of rice yackwa was examined by Instron, the structure by Scanning Electron Microscope, the color by Hunter's Colorimeter, and the sensory evaluation was also made. The resluts are as knows: The most stable egg white foam and whole egg foam were the 2 and 3 min. whipped ones, respectively. In the case of rice yackwa, which was made from 140 mesh rice flour and 60 g of whole egg, the hardness and the structure were similar to those of wheat yackm. It was very tasty and most preferred. As a whole, the color of rice yackwa was lighter man mat of wheat yackwa.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.4
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• pp.247-254
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• 1994

This study was conducted to characterize the chemical and mineralogical properties of representative phosphate rocks from North Carolina and Florida, and to find out the method for increasing the citric acid (two percent) solublility of phosphate rock. The the results are summerized as follows : 1. Major composition of phosphate rock was carbonate apatite containing small amounts of calcite and quartz. The differential thermal analysis(DTA) did not show endothermic or exothermic peak till $1,000^{\circ}C$. 2. Two percent citric acid solublility of phosphate rock was increased with the finess of particle size, but the water solublility was not affected by the particle size. Long time calcinated under high temperature had negative effect, while the incubation with 2% citric acid under low temperature had positive effect on solubility. 3. To increase the solubility of phosphate rock it was mixed with farmyard and barnyard manure and acidulated. Citrate solubility by treatment with sulfuric acid was more effective than nitric acid. Acidulation with thirty percent sulfuric acid increased both citric acid solubility and water solublility. Treatment with glutamic acid had little effect on the solubility of phosphate rock.