• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.229-236
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• 2015

In this study, the resilient modulus test and Light Weight Deflectormeter (LWD) test were conducted to simulate the moving vehicle load for the evaluation of the internal failure of epoxy asphalt pavement. The Measured displacement in the resilient modulus test of epoxy asphalt concrete showed very little residual deformation under repeated loads unlike the conventional asphalt. Therefore, the test results were evaluated as a normal state due to its similarity with elastic deformation. The deflection results from the resilient modulus tests were converted to the surface deflection modulus and the normal range of surface deflection modulus was estimated applying LWD measurement of 1 SIGMA level. Internal failure of pavements were estimated using the suspicious failure range at $60^{\circ}C$ and hysteresis. Internal moisture penetration and a decrease in bonding were observed in partial areas at $140{\mu}m$ of surface deflection. However, the areas showed inflection points in the hysteresis. Field investigation by suggested criterion indicated a high degree of accuracy.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.39 no.6
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• pp.585-590
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• 2002

In the typical data partitioning for error-resilient video coding, motion and macroblock header information is separated from the texture information. It can be an effective tool for the transmission of video over the error prone environment. For Intra-coded frames, however, the loss of DCT (discrete cosine transform) coefficients is fatal because there is no ther information to reconstruct the corrupted macroblocks by errors. For Inter-coded frames, when error occurs in DCT coefficients, the picture quality is degraded because all DCT coefficients are discarded in those packets. In this paper, we propose an efficient data partitioning and coding method for DCT-based error-resilient video. The quantized DCT coefficients are partitioned into the even-value approximation and the remainder parts. It is shown that the proposed algorithm provides a better quality of the high priority part than the conventional methods.

• The Journal of Korean Academy of Prosthodontics
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• v.31 no.1
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• pp.19-27
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• 1993

For the purpose of this study was to determine the growth of Candide albicans on the surface of the resilient denture liners. The discs$(40\times40mm)$ of 2 resilient lining materals (Molloplast B, Mollosil) and one conventional acrylic resin (K-33) and one metal plate were processed and disinfected. Firstly, the test discs were placed into petri dish, and Candide albicans suspensions was overlayed on the test discs. And the test discs were incubated with intermitant shaking for 1 hour, 2 hours, 6 hours, 12 hours, 24 hours. After incubation, imprint culture method was achived and counted the colony on the agar plate. Secondly, the effect of denture cleansing agents on the growth of Candide alibicans on the resilient dentureliners was evaluated. The results were as follows : 1. The growth of Candida albicans on discs of Molloplast B and Mollosil was increased than that on discs of acrylic resin and metal plate (p<0.05). 2. As Candide albicans suspensions were incubated for 2 hours, the growth of Candida albicans on discs of Mollosil was increased than that on discs of Molloplast B (p<0.05), and the growth of Candide albicans on discs of metal plate was increased than that on discs of acrylic resin (p<0.05). 3. As Candide albicans suspensions were incubated for 6 hours, the growth of Candide albicans on discs of Mollosil was increased than that on discs of Molloplast B (p<0.05). 4. The growth of Candide albicans on discs of Mollosil and Molloplast B in treating denture cleansing agent was inhibited than control discs (p<0.05).

• International Journal of Highway Engineering
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• v.14 no.3
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• pp.49-58
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• 2012

In many countries including Korea, the design concept of pavement structure has been converted from empirical method to mechanisticempirical method since the advent of compaction control based on resilient modulus proposed by AASHTO in 1986. Studies of last decades indicates that the classical compaction control method based on relative compaction and plate bearing test(PBT) will necessarily move to the methods taking advantage of light falling weight deflectometer(LFWD) and dynamic cone penetrometer(DCP) in addition to PBT. In this study, the validity of resilient modulus prediction equation proposed by Korean Pavement Design Guide is verified by comparison with physical properties of subgrade soil and the results of structural analysis. In addition, correlational equations between elastic modulus measured by various field tests and resilient modulus estimated by empirical model are proposed. Finally, a field test-based compaction control procedure for subgrade is suggested by using proposed correlational equations.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.11
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• pp.141-149
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• 2013

IETF 6LoWPAN standard technique has been studied in IoT environment to support the IPv6 packet communication. 6LoWPAN protocol for transmission of packets mainly in the AODV routing protocol and a variety of extended techniques have been investigated. In particular, consisting of nodes with limited resources in a network error occurs when the 6LoWPAN reliable data transfer and fast routing method is needed. To this end, in this paper, we propose resilient routing protocol and extension of IETF LOAD algorithm, for optimal recovery path, More specifically, the optimal recovery path setup algorithm, signal flow, and detailed protocols for the verification of the reliability of packet transmission mathematical model is presented. The proposed protocol techniques to analyze the performance of the NS-3 performance through the simulation results that is end-to-end delay, throughput, packet delivery fraction and control packet overhead demonstrated excellence in comparison with existing LOAD.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1404-1414
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• 2008

In the mechanistic-empirical trackbed design of railways, the resilient modulus is the key input parameter. This study focused on the resilient modulus prediction model, which is the functions of mean effective principal stress and axial strain, for three types of railroad trackbed materials such as crushed stone, weathered soil, and crushed-rock soil mixture. The model is composed with the maximum Young's modulus and nonlinear values for higher strain in parallel with dynamic shear modulus. The maximum values is modeled by model parameters, $A_E$ and the power of mean effective principal stress, $n_E$. The nonlinear portion is represented by modified hyperbolic model, with the model parameters of reference strain, ${\varepsilon}_r$ and curvature coefficient, a. To assess the performance of the prediction models proposed herein, the elastic response of a test trackbed near PyeongTaek, Korea was evaluated using a 3-D nonlinear elastic computer program (GEOTRACK) and compared with measured elastic vertical displacement during the passages of freight and passenger trains. The material types of sub-ballasts are crushed stone and weathered granite soil, respectively. The calculated vertical displacements within the sub-ballasts are within the order of 0.6mm, and agree well with measured values with the reasonable margin. The prediction models are thus concluded to work properly in the preliminary investigation.

• Journal of the Society of Disaster Information
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• v.14 no.3
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• pp.352-359
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• 2018

Purpose: This study aims to suggest new strategy of planning water management and land use in response to abnormal weather which allow waterfront to be the cities through the experience of Netherlands resilient project. Method: A planning direction is developed based on Dutch national resilient policy and strategy as well as resilient theory of technical and social aspects, focusing on a new waterfront development that responds to abnormal weather. Results: The water control strategy, for flexibly responding to the sea level rise and flooding caused by the climate change through the experience of Dutch resilience, is as follows: 1)Customized prevention plan according to the local property 2)Creating spatial planning by considering disaster risk level and fragility 3)Establishing urban planning by considering the flood risk level. Conclusion: A new urban development method, particularly a resilience strategy based on the waterfront space where is most vulnerable to climate change, is required to cope with the abnormal climate beyond the conventional planning.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.2
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• pp.206-212
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• 2006

Many image and video compression algorithms work by splitting the input image into blocks and producing variable-length coded bits for each block data. If variable-length coded data are transmitted consecutively, then the resulting coder is highly sensitive to channel errors. Therefore, most image and video techniques for providing some protection to the stream against channel errors usually involve adding a controlled amount of redundancy back into the stream. Such redundancy might take the form of resynchronization markers, which enable the decoder to restart the decoding process from the known state, in the event of transmission errors. The Error Resilient Entropy Code (EREC) is a well known method which can regain synchronization without any redundant information to convert from variable-length code to fixed-length code. This paper proposes an enhancement to EREC, which greatly improves its transmission ability for the compressed image quality without any redundant bits in the event of errors. The simulation result shows that the both objective and subjective quality of transmitted image is enhanced compared with the existing EREC at the same BER(Bit Error Rate).

• Journal of the Society of Disaster Information
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• v.19 no.3
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• pp.562-571
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• 2023

Purpose: This study aims to provide a direction for restructuring resilient waterfront spaces, emphasizing the severity of water-related disasters and the significance of developing responsive urban strategies. Method: To achieve this objective, the study analyzes overseas planning and design cases based on the theoretical framework of urban resilience. The goal is to identify physical and social systemic design elements that can be applied to waterfront space planning and design of Korea. Result: The proposals from the Resilient by Design Callenge included strategies for enhancing social systems and promoting sustainability in a more systematic manner. Additionally, various physical design strategies and technologies were identified in the Sponge City projects, which aim to create a flexible urban waterfront space. Conclusion: When planning and designing Korean waterfront spaces to effectively respond to disasters, several elements should be considered, such as enhancing educational functions, expanding local resident participation, establishing a governance system, developing systematic sustainable plans, adopting ecological approaches, and implementing various low-impact development techniques.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1115-1122
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• 2011

Reinforced-Roadbed materials are usually composed of crushed stones. Repeated load application can induce deformation in the reinforced-roadbed layer so that it causes irregularity of track. Thus it is important to develop a prediction model of elastic modulus based on stress-strain relation under repeatitive load in order to investigate behavior of reinforced roadbed. The prediction model of elastic modulus of the material can be obtained from repeated triaxial test. However, a proper size of the sample for the test must be used. In this study, a large repeatitive triaxial test apparatus with the sample size of diameter of 30 cm and height of 60cm was adapted for performing test of the crushed stone reinforced-roadbed considering large particle size to get resilient modulus Mr. The obtained resilient modulus was compared to shear modulus obtained from mid size resonant column test. The sample size effect is somewhat large enough so that it is required to design a scale factor based on similarity law in order to use smaller samples for getting elastic modulus of the crushed stone reinforced-roadbed material. A scale factor could be obtained from this study.