• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.483-493
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• 2013

The high strength materials have been more widely used in a large reinforced concrete structures. It is known that the use of high strength material in RC structures give the benefits of the mechanical and durable properties, but the ductility decreases with an increase in the strength of the materials. In the design of a reinforced concrete beam, both the flexural strength and ductility need to be considered. So, it is necessary to assess accurately the ductility of the beam with high strength materials in order to ensure the ductility requirement in design. In this study, the effects of the material strength on the flexural behavior and curvature ductility factor of reinforcement concrete beam sections with various reinforcement conditions have been evaluated and a newly prediction formula for curvature ductility factor of RC beam has been developed considering the stress of compression reinforcement at ultimate state. The proposed predictions for the curvature ductility factor which is applicable to both singly and doubly reinforced concrete beam are verified by comparisons with other prediction formulas and the proposed formula offers fairly accurate within 9% error and consistent predictions for curvature ductility factor of reinforced concrete beam.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.1
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• pp.41-48
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• 2016

Edentulous patients with severe alveolar bone resorption have trouble with using traditional complete denture. In order to overcome these problems, implant-retained overdenture was developed. SFI-bar$^{(R)}$ system can save time and cost compared to other existing bar systems which need complicated laboratory procedures because it can be adjusted directly in a patient's mouth. A 55-year-old male, who had experienced a fractured lower old implant-retained overdenture, wanted a durable and painless denture. The fractured Locator$^{(R)}$ attachments were removed and edentulous mandible was restored with SFI-bar$^{(R)}$. A 77-year-old female with a medical history of the Parkinson's disease and severely absorbed alveolar bone of mandible, wanted to wear a retentive mandibular denture without pain. After placing two implants in front of mental foramen, two adaptors were connected to two implants and a tube bar was connected to the adaptors. A female part fitted to the bar was attached to the new denture. These clinical reports describe two-implant-retained overdenture using the SFI-bar$^{(R)}$ system in mandibular edentulous patients. Since the patients were satisfied esthetically and functionally during 2 years' observation, we would like to report cases.

• Journal of the Korea Concrete Institute
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• v.17 no.4 s.88
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• pp.581-586
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• 2005

High-performance concrete (HPC), which is particularly sensitive to self-desiccation, is required to be durable even in severe environmental conditions, i.e. costal area, cold district, etc. However, in recent years, some attention was particularly given to cracking sensitivity of high performance concrete at early age. It has been argued and demonstrated experimentally that such concrete undergoes autogenous shrinkage due to self-desiccation at early age under restrained condition, nd, as a result, internal tensile stress may develop, leading to micro cracking and macro cracking. This shrinkage-introduced crack produces a major serviceability problem for concrete structures. One possible method to reduce cracking due to autogenous shrinkage is the addition of expansive additive. Tests conducted by many researches have shown the beneficial effects of addition of expansive additive for reducing the risk of autogenous shrinkage-introduced cracking. However, the research on hydration model of expansion additive has been hardly researched up to now. This paper presents a study of the hydration model of Ettringite-Gypsum type expansive additive. As a result of comparing forecast values with experiment value, proposed model is shown to expressible of hydration of expansive additive.

• Journal of Environmental Policy
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• v.14 no.3
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• pp.75-94
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• 2015

The purpose of this study is to analyze the major issues discussed among Parties and provide a framework for predicting the agreements on those issues, prior to the final negotiation on a new legally-binding agreement on climate change adaptation in the United Nations Framework Convention on Climate Change (UNFCCC). The analyses of documents, adaptation actions, and work of the Ad Hoc Working Group on the Durban Platform for Enhanced Action (ADP) under the UNFCCC informed that the adaptation issue has primarily been focused on the support of developed country Parties for the adaptation of developing country Parties following the principle of the Convention, Common but Differentiated Responsibilities and Respective Capabilities (CBDR-RC). Three-year work of the ADP acknowledged the major issues on adaptation in the new climate agreement, which would be categorized as long-term and global aspects, commitments/contributions/actions, monitoring and evaluation, institutional arrangements, and loss and damage. A final agreement on each issue could be predicted by setting a zone of possible agreement in-between the two extremes of developing and developed country Parties and considering three major elements affecting the Parties' positions, national priority, adaptation action, and social expectation, which are proposed in this study. The three major elements should be considered in a balanced manner by Parties to draw a durable agreement that will enhance global adaptation actions from a long-term perspective. That is, the agreement needs to reflect adaptation actions occurring outside the Convention as well as social expectations for adaptation. It is expected that the new agreement on climate change adaptation, from a long-term and global perspective, would be an opportunity to reduce vulnerability and build resilience to climate change by incorporating global expectations.

• Journal of the Korea Concrete Institute
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• v.20 no.2
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• pp.185-191
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• 2008

To fundamentally solve the problem of deterioration of concrete structures, it has been researched that the high durable concrete structure reinforced with the FRP rebar can be one of major solution to the newly-developed concrete structure. FRP rebar has lots of advantages such as non-corrosive, high performance and light weight against the conventional steel rebar. Among these kinds of FRP rebars, GFRP rebar has usually been considered as the best reinforcement because of its economic point of view. Even though the material capacity of the GFRP rebar was already investigated, there are some problems such as low modulus of elastic that will be cause for degrade of the serviceability of flexural concrete member reinforced with the GFRP rebar. Thus, the deflection characteristics of the GFRP rebar reinforced concrete structure should be considered then investigated. In this study, ACI 440 guideline (2003), ISIS Canada Design Manual (2001) and Toutanji et al. (2000) was considered for predicting the moment of inertia of the concrete beam reinforced with the GFRP rebar. And it was also evaluated that load-deflection relationship had a good accordance with the test and analysis result. In the result of this study, it could be estimated that the load-deflection relationship using the suggested equation of moment of inertia in this study indicated better accordance with the test result than that of the others until failure.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.2
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• pp.263-268
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• 2016

A rapid increase of data amount, used in ship-to-ship transmission of safety and logistics information, ships in the inland sea have trouble transmitting real-time information transmission due to an increase in traffic load caused by data transmitted by land station and offshore ships. In this study, therefore, communication is carried out by adaptively controlling the detailed beam width based on the distribution of offshore ships in land station durable in marine environment. Then after the adaptive sector system enabling real-time communication support between ships concentrated in an inland sea and land station is applied, the performance verification is conducted based on the respective Call Blocking Rates of an omnidirectional antenna, fisted sector system, and adaptive sector system. The performance verification result shows that adaptive sector system has better performance than the fixed sector system as the density of ship, q value, increases, and that the smaller the beam width is, the better performance of adaptive sector system will be.

• Journal of Conservation Science
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• v.28 no.4
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• pp.329-341
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• 2012

Magai Wareiishi Jizo (Buddhist statue carved on rock surface) is close to shoreline and a part of rock block is periodically immersed by seawater. Rock material of the Wareiishi-jizo statue is composed mainly of medium or coarse-grained biotite granite and very durable. However, physical properties of the rock have been changed according to the complex interactions of the salt solution and surrounding environment. Exfoliation of the rock surface is a serious condition by salt crystallization. Exfoliation (14.6%) is concentrated on the upper part of the rock block with mainly boundary of seawater as the center. On the other hand, lower part of the rock block show black layers by contaminants deposition. In addition, brown discoloration and biological contaminants is overlapped. Rock surface show high discoloration rate of 50.5% (black discoloration, 29.2% > yellow discoloration, 14.1% > brown discoloration, 4.4% > green discoloration, 2.9%). Upper part of the rock block had a lot of change in the physical properties than lower part that is immersed by seawater. In particular, surface properties of the rock block was very weak state at the boundary surface of seawater permeation.

• Archives of design research
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• v.17 no.1
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• pp.383-392
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• 2004

The power tools is the product using working power generated by electric motor. Many companies are manufacturing numerous devices. Main features of tools are included various assembled products, small, light and solid and durable enough to match several standards. Fundamental requirements for the product is excellent performance and convenience for use. The quality of them depends on the equipped motor'(s) capability, accuracy of gear and endurance against worn-out. By adapting the state-of-the-art parts, they could be used in the place from home to heavy industry broadly. They can be classified electronic drills, grinders, saws and sanders families for the household appliances. For industrial tools, bore drill, grinder, polisher, and driver drill are classified as special and high priced group. This study presents the strategy of power tool development of BOSCH, BLACK&DECKER and KEYANG. Their products were analyzed in terms of product line and product mix concept. Then they are examined by design elements, such as color, shape and material for housing. As an analysis method, the image scale parameter and criteria were applied to each company's product.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.616-620
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• 2011

Purpose: Mayer-Rokitansky-Kuster syndrome (MRK) is second common cause of primary amenorrhea. It is a syndrome of vaginal aplasia and Mullerian duct anomaly. Vaginal aplasia varies from agenesis of whole vagina to aplasia of upper 2/3. For reconstructing vagina, various methods are introduced. Gracilis myocutaneous flap was the first attempt in that the flap is used in vaginal reconstruction. Various flap-based vaginal reconstruction methods have been introduced. Modified Singapore flap (pedicled neurovascular pudendal thigh fasciocutaneous flap) is one of those methods that used posterior labial artery as pedicle, and pudendal nerve branch as sensory root. As its donor lies on inguinal crease that is easily hidden and there are benefits on sexual intercourse by early sensory recovery, authors think that modified Singapore flap is effective for young MRK syndrome patients. Methods: Eight patients underwent surgery between 2008 and 2010. The flap was designed on both groin area with external pudendal artery branch as a pedicle. All flaps were fixated in pelvic cavity with absorbable suture, and additional compression on neovaginal wall was supplied by polyvinyl alcohol sponge ($Merocel^{(R)}$). Results: All patients were successfully reconstructed without flap related complications such as congestion or partial flap loss. The average size of the flap (each side) was 69.34 $cm^2$. Polyvinyl alcohol sponge ($Merocel^{(R)}$) was inserted into neovagina for 5 days on every patient. One case of rectal laceration was occurred while making pelvic pocket by OBGY team. Other complications such as lumen narrowing, wound contracture or vaginal prolapsed were not reported during 8 months of follow up. Conclusion: Modified Singapore flap is a sensate fasciocutaneous flap that is thinner than other myocutaneous flap such as VRAM, and more durable over skin graft. Therefore this is a good choice for vaginal reconstruction in MRK syndrome. And known complications of Modified Singapore flap could be reduced with careful procedure and mild compression techniques.

• Parasites, Hosts and Diseases
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• v.53 no.5
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• pp.553-559
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• 2015

Research on micro-level assessment of the changes of socio-economic status following health interventions is very scarce. The use of household asset data to determine wealth indices is a common procedure for estimating socio-economic position in resource poor settings. In such settings information about income is usually lacking, and the collection of individual consumption or expenditure data would require in-depth interviews, posing a considerable risk of bias. In this study, we determined the socio-economic status of 213 households in a community population in an island in the north-western Tanzania before and 3 year after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention to control schistosomiasis and intestinal worm infections. We constructed a household 'wealth index' based housing construction features (e.g., type of roof, walls, and floor) and durable assets ownership (e.g., bicycle, radio, etc.). We employed principal components analysis and classified households into wealth quintiles. The study revealed that asset variables with positive factor scores were associated with higher socio-economic status, whereas asset variables with negative factor scores were associated with lower socio-economic status. Overall, households which were rated as the poorest and very poor were on the decrease, whereas those rated as poor, less poor, and the least poor were on the increase after PHAST intervention. This decrease/increase was significant. The median shifted from -0.4376677 to 0.5001073, and the mean from -0.2605787 (SD; 2.005688) to 0.2605787 (SD; 1.831199). The difference in socio-economic status of the people between the 2 phases was highly statistically significant (P<0.001). We argue that finding of this study should be treated with caution as there were other interventions to control schistosomiasis and intestinal worm infections which were running concurrently on Kome Island apart from PHAST intervention.