• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.4
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• pp.106-112
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• 2001

Recent advance in material technology has accelerated the development of high strength concrete using lightweight artificial aggregates. The lightweight concrete has many advantages that the reduction of dead loads and the increase in load capacity can offer. In this study the lightweight polymer concrete using unsaturated polyester resin and lightweight aggregate were prepared and tested for testing the physical and the mechanical properties. The compressive strengths of lightweight polymer concretes with apparent specific gravity for 1.32 to 1.78 were 250 to 470 kfg/cm$^2$ and flexural strengths were measured to be in the range of 1/3-1/4 of compressive strength.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.49.1-52
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• 2003

The objective of this study the mechanical characteristics of preformed lightweight foamed concrete using the mineral foam agent which has high lightness, and strength. The compressive strength of lightweight foamed concrete using mineral foam agent are about 2 times degree high those the of lightweight foamed concrete using vegetable foam agent. Lightweight foamed concrete was able to obtain the result of 50kg/$\textrm{m}^3$ or more compressive strength, when was unit weight 0.8t/$\textrm{m}^3$. In the can of the same unit weight of concrete, it is influenced by w/c of loan agent ratio. The paper present extensive data on characteristics of compressive strength of the concrete manufactured with the different factors in mix design and also present optimum mix proportion.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1139-1144
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• 2000

Recent advance in material technology has accelerated the development of high strength concrete using lightweight artificial aggregates. The lightweight concrete has many advantages that the reduction of dead lads and the increase in load capacity can ofter. In this study, lightweight polymer concrete using unsaturated polyester resin and lightweight aggregate were prepared and tested for testing the physical and the mechanical properties. The compressive strengths of lightweight polymer concretes with specific gravities from 1.32 to 1.78 were compressive strength of 250 to 470 $kgf/cm^2$ and flexural strengths were measured to be in the range of a third to a quarter of compressive strength

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.241-244
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• 2005

The existing structural lightweight concrete is almost manufactured by using lightweight aggregate. But most of a lightweight aggregate depends on income, it is wholly lacking domestic utilizer. So in this study we investigate the developmental possibility of structural lightweight concrete using only the aggregate of the general concrete and foam agent. As the result of experiments this paper confirmed the possibility of development of structural lightweight concrete which shows compressive strength 210kgf/$cm^{2}$ and specific gravity 1.8 t/$m^{3}$ using only foam agent

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.105-106
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• 2015

As the Long-life certification system is recently introduced in the Housing Law in Korea, it is expected that an application of the lightweight wall panel will be increased in apartment construction as the main wall system. However, the performance criteria for lightweight wall is in the early phase of its action. Therefore, it is necessary to establish the performance criteria properly by investigating performance requirement in the user's perspective. The purpose of this study is to identify of the weight of the required performance items for the lightweight wall in apartment house. To analyze the priority in the performance, an interview survey is performed; after monitering the test-bed of the lightweight walls, user and experts evaluate the performance requirements. The weight of the performance requirement is developed by AHP method.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.118-119
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• 2018

The purpose of this study is to investigate the compressive strength and mixing properties of the lightweight block, which has been manufactured without the pre-wetting process, in the lightweight block using domestic artificial lightweight aggregate. The test results of the specimens produced within 30 minutes after the preparation showed high compressive strength but poor permeability. Therefore, the elapsed time after the manufacture, which is expected to have required compressive strength and permeability, was about 60 minutes in this study.

• Steel and Composite Structures
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• v.3 no.3
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• pp.199-212
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• 2003

An experimental investigation of lightweight aggregate and foamed concrete contribution to the ultimate strength capacity of square and rectangular steel tube sections is presented in this study. Thirty-four simply supported beam specimens, 1000-mm long, filled with lightweight aggregate and foamed concretes were tested in pure flexural bending to calculate the ultimate moment capacity. Normal concrete-filled steel tubular and bare steel sections of identical dimensions were also tested and compared to the filled steel sections. Theoretical values of ultimate moment capacity of the beam specimens were also calculated in this study for comparison purposes. The test results showed that lightweight aggregate and foamed concrete significantly enhance the load carrying capacity of steel tubular sections. Furthermore, it can be concluded from this study that lightweight aggregate and foamed concretes can be used in composite construction to increase the flexural capacity of the steel tubular sections.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.533-536
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• 2004

This study aims to manufacture and to evaluate lightweight cement composite using lightweight aggregate and expanded perlite. The expanded perlite and lightweight aggregates were mixed with cement, water, SP(superplasticizer), forming-agent and poly-propylene fiber. The specimens were cured at $20^{\circ}C$ for 24h and then at steam curing of $60^{\circ}C$, RH $100\%$ for 12h. As a result, We could make lightweight cement composite of satisfaction about ALC properties. However it is need to improve the properties of density and water absorption.

• Journal of Information Processing Systems
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• v.18 no.1
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• pp.12-25
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• 2022

In recent years, deep convolutional neural networks have made significant progress in the research of single image super-resolution. However, it is difficult to be applied in practical computing terminals or embedded devices due to a large number of parameters and computational effort. To balance these problems, we propose CSRNet, a lightweight neural network based on channel split residual learning structure, to reconstruct highresolution images from low-resolution images. Lightweight refers to designing a neural network with fewer parameters and a simplified structure for lower memory consumption and faster inference speed. At the same time, it is ensured that the performance of recovering high-resolution images is not degraded. In CSRNet, we reduce the parameters and computation by channel split residual learning. Simultaneously, we propose a double-upsampling network structure to improve the performance of the lightweight super-resolution network and make it easy to train. Finally, we propose a new evaluation metric for the lightweight approaches named 100_FPS. Experiments show that our proposed CSRNet not only speeds up the inference of the neural network and reduces memory consumption, but also performs well on single image super-resolution.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.61-62
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• 2021

Because of the problem of increasing self-weight due to the enlargement and high-rise of buildings using normal aggregate concrete, the need for structural lightweight aggregate concrete increases. However, early strength prediction is required when placing structural lightweight aggregate concrete, but research is insufficient. In this study, the ultrasonic pulse velocity of normal aggregate concrete and lightweight aggregate concrete was measured at early age. As a result, the ultrasonic pulse velocity of lightweight aggregate concrete was lower than normal aggregate concrete according to elapsed time at early age.