• The Journal of Korean Academy of Prosthodontics
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• v.23 no.1
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• pp.97-112
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• 1985

The purpose of this study was to evaluate the stress patterns developed in supporting structures by removable partial denture with attachment retainers. The attachments tested were Dalbo(miniature) attachment, resilient Ceka attachment, rigid Ceka attachment, precision and sleeve attachment, and R.P.I. clasp as a contrast. 3-dimensional photoelastic stress analysis was used to record the isochromatic and isoclinic fringe patterns and to calculate principal stress components at measuring points. The results showed that: 1. The maximum compressive stress on residual ridge was produced under the loading point with Dalbo and resilient Ceka attachment, distal to the loading point with rigid Ceka and precision and sleeve attachment, and mesial to the loading point with R.P.I. clasp. 2. The Dalbo attachment produced the most stress on residual ridge, and the least stress on abutment teeth. and resilient Ceka attachment showed favorable stress distribution. 3. Rigid Ceka attachment produced higher compressive stress on buccal. alveolar crest, and precision and sleeve attachment produced higher compressive stress on distal alvelolar crest and mesial surface of the root apex in abutment teeth. 4. R.P.I. clasp produced higher compressive stress on mesial alveolar crest.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1712-1723
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• 2008

In the trackbed design using an elastic multi-layer model, the stress-dependent resilient modulus is the key input parameter, which reflects substructure performance under repeated traffic loading. The prediction models of resilient modulus of crushed stone and weathered granite soil were developed from nonlinear dynamic stiffness, which can be combined by in-situ and laboratory seismic measurements. The models accommodate the variation with the deviatoric and/or bulk stresses. To investigate the performance of the prediction models proposed, the elastic response of the test trackbed near PyeongTaek, Korea was evaluated using a 3-D nonlinear elastic computer program (GEOTRACK) and compared with measured elastic vertical displacement caused by the passages of freight and passenger trains. The material types of the test sub-ballasts are crushed stone and weathered granite soil, respectively. The calculated vertical displacements within the sub-ballasts are within the order of 1mm, 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 Earthquake Engineering Society of Korea
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• v.24 no.4
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• pp.169-178
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• 2020

In a previous paper, ambient vibration tests were conducted on a cable stayed bridge with resilient-friction base isolation systems (R-FBI) to extract the dynamic characteristics of the bridge and compare the results with a seismic analysis model. In this paper, a nonlinear seismic analysis model was established for analysis of the bridge to compare the difference in seismic responses between nonlinear time history analysis and multi-mode spectral analysis methods in the seismic design phase of cable supported bridges. Through these studies, it was confirmed that the seismic design procedures of the "Korean Highway Bridge Design Code (Limit State Design) for Cable Supported Bridges" is not suitable for cable supported bridges installed with R-FBI. Therefore, to reflect the actual dynamic characteristics of the R-FBI installed on cable-supported bridges, an improved seismic design procedure is proposed that applies the seismic analysis method differently depending on the seismic isolation effect of the R-FBI for each seismic performance level.

• Journal of the Korean Institute of Gas
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• v.17 no.4
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• pp.77-82
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• 2013

The construction of LNG storage tanks has been increased due to the expansion of LNG demand. LNG tanks which consist of an inner cylindrical 9%Ni metal tank and reinforced concrete, are insulated with perlite powder and resilient blanket for absorbing the perlite pressure in insulation annulus between two inner and outer tanks. This study tries to find out the design specifications and characteristics for blanket thickness and design pressure. The results show that the design basis for the blanket thickness should be approximately 30% to 40% of annulus width and the design pressure be applied below 2,200~2,700Pa with blanket thickness.

• Journal of the Society of Disaster Information
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• v.7 no.1
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• pp.32-42
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• 2011

Many researches have been conducted to evaluate the performance of modified asphalt concrete mixtures. The research was conducted to estimate the laboratory mechanical characteristics of Elvaloy-modified asphalt concrete mixture. To achieve its intended objective, indirect tensile test and resilient modulus test were performed. The rest results revealed that indirect tensile strengths and resilient moduli of the Elvaloy-modified asphalt concrete mixture were higher than those of the conventional dense-graded. As a result, within the limits of the tests conducted in this research, it is predicted that the performance and stability of the Elvaloy-modified asphalt concrete mixture are better than that of the conventional dense-graded one.

• Food Science and Industry
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• v.54 no.3
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• pp.196-209
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• 2021

The origines of the Western roasting culture and East Asian boiling culture were studied and the importance of primitive pottery culture (8000-5000 BCE) in the Korea Strait coastal region was discussed. The primitive pottery culture probably initiated the Jjigae (stew) culture and the production of salt. It can be also postulated that fish fermentation, kimchi fermentation, and cereal alcohol fermentation originated during this period. Soybean culture emerged ca. 2,000 BCE in South Manchuria and the Korean Peninsula. This paper focuses on the role of Korean foodways in the food science and technology development for the sustainable and resilient food systems. We are facing a global food crisis caused by population growth, climate change, and high animal food consumption. Studies on the meat analog and cultured meat are the new trend in Food Science and Technology. The importance of the wisdom learned through the Northeast Asian traditional foods, for example, soybean curd (tofu) and meaty flavor production by fermentation for the research on the novel sustainable and resilient food systems are discussed.

• Steel and Composite Structures
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• v.47 no.3
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• pp.315-337
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• 2023

The steel structure is an assembly of individual structural members joined together by connections. The connections are the focal point to transfer the forces which is susceptible to damage easily. It is challenging to replace the affected connection parts after an earthquake. Hence, steel plates are utilised as a structural fuse that absorbs connection forces and fails first. The objective of the present research is to develop a beam-column end plate connection with single and dual fuse and study the effect of single fuse, dual fuse and combined action of fuse and damper. In this research, seismic resilient beam-column end plate connection is developed in the form of structural fuse. The novel connection consists of one main fuse was placed horizontally and secondary fuse was placed vertically over main fuse. The specimens are fabricated with the variation in number of fuse (single and dual) and position of fuse (beam flange top and bottom). From the fabricated ten specimens five specimens were loaded monotonically and five cyclically. The experimental results are compared with Finite Element Analysis results of Arunkumar and Umamaheswari (2022). The results are critically assessed in the aspect of moment-rotation behaviour, strain in connection components, connection stiffness, energy dissipation characteristics and ductility. While comparing the performance of total five specimens, the connection with fuse exhibited superior performance than the conventional connection. An equation is proposed for the moment of resistance of end-plate connection without and with structural fuse.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.303-312
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• 2020

Safety culture is a collection of the beliefs, perceptions and values that employees share in relation to risks within an organisation. On the other hand, a resilient safety culture (RSC) means a culture with readiness of the organisation to respond effectively under stress, bounce back from shocks and continuously learn from them. RSC helps organisations to protect their interest which can be attributed to behavioural, psychological and managerial capabilities of the organization. Quantification of the degree of resilience in an organisation's safety culture can provide insights about the strong and weak links of the organisation's overall health and safety situation by identifying potential causes of system or sub-system failure. One of the major challenges of quantification of RSC is that the attributes that determine RSC need to be measured through constructs and indicators which are complex and often interrelated. In this paper, we address this challenge by applying a fault tree analysis (FTA) technique which can help analyse complex and interrelated constructs and indicators. The fault tree model of RSC is used to evaluate resilience levels of two organisations with remote and urban locations in order to demonstrate the failure path of the weak links in the RSC model.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.3 s.309
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• pp.9-16
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• 2006

Many image and video compression algorithms work by splitting the image into blocks and producing variable-length code bits for each block data. If variable-length code data are transmitted consecutively over error-prone channel without any error protection technique, the receiving decoder cannot decode the stream properly. So the standard image and video compression algorithms insert some redundant information into the stream to provide some protection against channel errors. One of redundancies is resynchronization marker, which enables the decoder to restart the decoding process from a known state in the event of transmission errors, but its usage should be restricted not to consume bandwidth too much. The Error Resilient Entropy Code(EREC) is well blown method which can regain synchronization without any redundant information. It can work with the overall prefix codes, which many image compression methods use. This paper proposes EREREC method to improve FEREC(Fast Error-Resilient Entropy Coding). It first calculates initial searching position according to bit lengths of consecutive blocks. Second, initial offset is decided using statistical distribution of long and short blocks, and initial offset can be adjusted to insure all offset sequence values can be used. The proposed EREREC algorithm can speed up the construction of FEREC slots, and can improve the compressed image quality in the event of transmission errors. The simulation result shows that the quality of transmitted image is enhanced about $0.3{\sim}3.5dB$ compared with the existing FEREC when random channel error happens.

• The Journal of Korean Academy of Prosthodontics
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• v.25 no.1
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• pp.137-154
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• 1987

The purpose of this investigation was to determine the surface characteristics and the fittness of the resilienct denture lines. Firstly, 50 samples ($2.0{\times}4.0{\times}0.3cm$) of 4 resilient lining materials (Molloplast B, Coe Super Soft, Mollosil, Coe Soft) and one conventional acrylic resin (K-33) were processed according to manufacture's direction and examined the surface characteristics by use of surface profilometer and scanning electron microscopy. Secondly, 50 identical maxillary casts were made and 50 denture bases were pro cessed of 4 resilient liners and one conventional acrylic resin and they were stored in the room temperature water bath of 1 day, 1 week, 2 weeks, 3 weeks, 4 weeks and 6 weeks after processing. The original casts were cut away 1 cm from the posterior border, the dentures were seated, and the existing space was measured at seven regions according to the storage time by use of the modified thickness guage. The results were as follows. 1. Surface roughness (Rz) were $4.00{\pm}1.60{\mu}m$ in Mollosil, $4.47{\pm}2.21{\mu}m$ in Molloplast B, $7.46{\pm}1.70{\mu}m$ in Coe Super Soft, $12.70{\pm}2.39{\mu}m$ in Coe Soft and $13.03{\pm}2.74{\mu}m$ in K-33. 2. The generation of porosity was far more active in cold-cured resilient liners (Coe Soft and Mollosil) than in heat cured resilient liners (Molloplast B, and Coe Super Soft) and conventional heat cured resin (K-33). 3. Denture bases showed the greatest discrepancy at the central portion of the posterior palatal border and the intimate contact in the buccal flange regardless of denture base materials. 4. When the denture bases were stored in the water for 1 day and 6 weeks after processing, the sum of average discrepancies in the seven regions of the denture base was the greatest in K-33 followed by Molloplast B, Mollosil, Coe Soft and Coe Super Soft but followed by Coe Soft, Molloplast B, Mollosil, Coe Super Soft in that order respectively. 5. There was not a significant difference (p>0.05) in Coe Super Soft, K-33 but there was a significant difference (P<0.01) in Molloplast B, Mollosil, Coe Soft at the amount of dimensional changes according to the storage time.