• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.06a
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• pp.230-231
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• 2014

Compressive sensing is a new sampling technique, which allows to sample a signal under the Nyquist-Shannon sampling rate. For block-based compressive sensing, a hybrid sensing matrix which contains low-frequency patterns in addition to the random Gaussian numbers is good for exploiting typical property of natural images. By noting that MH-BCS-SPL is well known for its good recovery performance, this paper investigates effect of the hybrid sensing matrix on MH-BCS-SPL in the sense of how large portion of low-frequency patterns can provide performance improvement.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.136-141
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• 1998

While a little research has been peformed on flexural behavior of reinforced polymer concrete (RPC)beams with the compressive strength lower than 900kg/$\textrm{cm}^2$ vary little exists in conjunction with the behavior of RPC 1,000kg/$\textrm{cm}^2$ or higher in compressive strength. In this paper the flexural performance of high strength polymer concrete beams with 1,450kg/$\textrm{cm}^2$ in compressive strength was evaluated. The unsaturated polyester resin was used to make polymer concrete as binder. The beams with stirrup singly/doubly were tested to examine the effect of tensile reinforcement ratio. As test results, reinforcement ratio increased with the increase moment strength, decreased with ultimate deflection, ductility index.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.528-531
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• 2004

Nowadays, many of PSC bridges has constructed because high performance and long span bridge is required. Therefore, it is required that the evaluation of PSC bridges which retain various structure performance. In this study, nonlinear FEM analysis was performed with two parameter, concrete compressive strength and effective prestress force which is dominant factor for evaluating structural behavior of PSC bridge. Concrete compressive strength was adapted between 30Mpa and 100Mpa and effective prestress force was used the value which is considered effective rate for time-dependant effect. In the result of this study, it was showed that concrete compressive strength and effective prestress force is important factor for evaluating structural behavior of PSC bridge.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.289-292
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• 2006

The purpose of this study was to evaluate a performance of latex-modified repair material applied to the substrate concrete. The experimental variables were latex-cement ratios (5, 10, 15%), polymer(0.5%, 1%) and admixtures. The flow, air content, compressive strength, flexural strength were tested. Test results showed that compressive and flexural strength decreased by adding hydroxyethyl cellulose and increasing water-binder ratio. The compressive and flexural strength were increased when addition of defoamer.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.11
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• pp.67-72
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• 2011

In this paper, we investigate the energy detector to detect a primary user. And employ the compressed sensing method to get the lower sampling rate than Nyquist sampling rate. In more wide bandwidth we using the small samples than Nyquist sampling rate samples to recover original signal. we investigate the performance of energy detector with compressive sensing method under suzuki channel. The performance is investigated by simulation and compared to that of conventional energy detector.

• Journal of Korean Association for Spatial Structures
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• v.17 no.1
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• pp.59-67
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• 2017

In this study, load transfer tests based on KCI-PS101 were conducted to verify the performance of spiral anchorage zone reinforcement for banded post-tensioning (PT) monostrands. With results, the compressive strength of spiral reinforcement was increased by about 20% than that of specimens with two horizontal steel bars and 8% than that of U-shaped bars. Advanced spiral reinforcement for corner increases compressive strength and can resist the spalling forces or fall-out effect at the corner by shear. The ratio of maximum load to amount of steel of the spiral reinforcement is about twice than that of U-shaped reinforcement. With increase of compressive strength capacity and improvement of constructability, the spiral reinforcement is considered to have advantages of promoting the performance of PT anchorage zone compared to conventional methods.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.229-232
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• 2006

The HPFRCCs show that the multiple crack propagation, high tensile strength and ductility due to the interfacial bonding of the fibers to the cement matrix. Moreover, performance of cement composites varies according to type and weight contents of reinforcing fiber. and HPFRCCs with hybrid fiber have better performance than HPFRCCs with single fiber in damage tolerance. Total four cylindrical specimens were tested, and the main variables were the type and weight contents of fiber, which was polyvinylalchol (PVA), polyethylene (PE). In order to clarify effect of hybrid types on the characteristics of fracture and damage process in cement composites, AE method was performed to detect micro-cracking in HPFRCCs under cyclic compression. Loading conditions of the uniaxial compression test were monotonic and cyclic loading. And from AE parameter value, it is found that the second and third compressive load cycles resulted in successive decrease of the amplitude as compared with the first compressive load cvcle.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.57-64
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• 2013

PURPOSES : It is to evaluate lightweight soil as a subgrade material based on mechanical tests and calculation of pavement performance. METHODS : In this research, various contents of cement and air foam are used to make lightweight soil using wasted dredged soil. Uniaxial compressive strength test is conducted to evaluate strength of 7 and 28 day cured specimens. Secant modulus was calculated based on the stress and strain relationship of uniaxial compressive strength test. Resilient modulus test was measured using by repeated triaxial compression test. The measured resilient modulus was used in layered elastic program to predict fatigue and rutting life at a given pavement structure. RESULTS : Uniaxial compressive strength increases as cement content increases but decrease as air foam content increases. Resilient modulus also increases as cement content increases and decrease as air foam content decrease. CONCLUSIONS : It is concluded that dredge clay soil can be used as subgrade layer material using by lightweight treated soil method.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.321-322
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• 2023

This study compared the compressive strength and healing strength to confirm the self-healing performance of mortar incorporating Bioinspired Self-healing Capsule (BSC) into cement composites as part of a study to mitigate the problem of durability deterioration due to cracks in concrete structures. As a result of the evaluation, it was found that the healing performance decreased as the mixing ratio of the BSC capsule increased.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.299-300
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• 2023

In this study, the performance evaluation and structural safety of rainwater permeation detention block were analyzed. As a result, the compressive strength (19.3 MPa), flexural strength (5.2 MPa), and permeability coefficient (2.0 mm/s) of the eco-friendly prefabricated rainwater permeable detention block satisfied the KS F 4419 and SPS-KCIC0001-0703 and it was confirmed sufficient safety even under maximum load.