• Journal of the Korea Concrete Institute
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• v.27 no.4
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• pp.451-458
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• 2015

The infill-wall strengthening method has been widely used for the seismic performance enhancement of the conventional reinforced concrete (RC) frame structures with non-seismic detail, which is one of the promising techniques to secure the high resisting capacity against lateral forces induced by earthquake. During the application of the infill-wall strengthening method, however, it often restricts the use of the structure. In addition, it is difficult to cast the connection part between the wall and the frame, and also difficult to ensure the shear resistance performances along the connection. In this study, an advanced strengthening method using the externally-anchored precast wall-panel (EPCW) was proposed to overcome the disadvantages of the conventional infill-wall strengthening method. The one-third scaled four RC frame specimens were fabricated, and the cyclic loading tests were conducted to verify the EPCW strengthening method. The test results showed that the strength, lateral stiffness, energy dissipation capacity of the RC frame structures strengthened by the proposed EPCW method were significantly improved compared to the control test specimen.

• Journal of the Korean GEO-environmental Society
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• v.16 no.11
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• pp.13-19
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• 2015

Construction materials using soil which is the most common material around us have many advantages, but their long-term durability and sensation of walking as pavements have problems. Therefore, they are used after compaction or mixed with various hardening agents such as lime and cement for strength enhancement. However, studies on the behavior of pavement materials mixed with environment-friendly hardening agents or admixtures to improve walking property are still insufficient. In this study, therefore, in order to evaluate the appropriate mixing ratio and field application characteristics of pavement materials using mixed soils with environment-friendly hardening agents and natural materials such as wood chips, mechanical tests were performed to evaluate the rational mixing ratios and the ball test was performed as an elasticity test to evaluate the field applicability. The results suggest that the content of wood chips should be selected at 1.5% or lower according to the purpose of the structure, and the hardening agent at 10~15%. The evaluation results for GB/SB coefficient ratio which indicates the walking property show that the appropriate mixing ratio of the hardening agent in terms of the sensation of walking is 15% of lower, but different mixing ratios should be chosen according to the proportion of wood chips.

• Polymer(Korea)
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• v.29 no.2
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• pp.127-134
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• 2005

The relationships among mechanical properties, rheological properties, and morphology by reactive extrusion based on commingled pckaging film wastes contains polypropylene (PP) pckaging film system [PP/polyethylene (PE)/aluminum (Al)/poly(ethylene terephthalate) (PET)] and Nylon packaging film system[Nylon/PE/linear-low density polyethylene (LLDPE)] were investigated to improve the compatibility and toughness of these wastes using various compatibilizers such as ethylene vinylacetate (EVA), styrene-ethylene/butylene-styrene triblock copolymer (SEBS), styrene-ethylene/butylene-styrene-graft-maleic anhydride copolymer (SEBS-g-MA), polyethylene-graft-maleic anhydride (PE-g-MA), polypropylene-graft-maleic anhydride (PP-g-MA) , polyethylene-graft-acrylic acid (PE-g-AA) and polypropylene-graft-acrylic acid (PP-g-AA). Compared with simple melt blend system, the blends showed improvement of about $50\%$ increase in physical properties when SEBS and EVA were added. However, SEBS-g-MA thermoplastic elastomer which is highly reactive with amine terminal group of nylon, resulted in about $200\%$ increase in impact strength. This compatibilization effect resulted from the increase of interfacial adhesion and the reduction of domain size of dispersed phase in PP/Nylon blend system.

• Korean Journal of Oriental Medicine
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• v.16 no.3
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• pp.167-173
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• 2010

Objects : Glycine max Merr. (black bean), Triticum aestivum L. (wheat) and Oryza sativa L. (rice bran) have been widely used for treatment of relaxion of smooth muscle, gastrointestinal hemorrhage and alopecia in Korean Traditional Medicine. In this research, we examined the effect of the extracts, obtained from EtOH extracts of 3 kinds of traditional plants, on hair growing activity of the DP6 and C3H10T1 cell and physical properties. Materials and Methods : On the basis of previous studies, three traditional plants were selected and we extracted them with ethanol. We evaluated their hairy dermal papillar cell proliferation activity and mouse mesenchymal stem cell in vitro model. Also, 3 herbal extracts were added to the normal shampoo formulation in ranges of 0.1% and we validated tensile properties and physical changes using aged hair. In this research, we compared the tensile strength, shine and color appearance between the hair (general formulation) and the hair after applying shampoo with natural extracts. To analyze the luster and color image, we use the SAMBA hardware and software made by Bossa Nova Technologies. Results : In the comparative test for tensile characteristic between the hair treated general formulation(control) and the hair applying special formulation including 3 kinds of extracts, tensile distance and energy of the latter are larger than control on average. The shine and color appearance were also increased after using shampoo including natural extracts(shine : 10.9%, color appearance: 24.12%). We observed the enhancement of hair growth activity in the DP6 and C3H10T1 cell. Especially black bean extracts had the most powerful effect in the dermal papillar cell proliferation. Conclusion : These experiments suggest that extracts of Glycine max Merr. (black bean), Triticum aestivum L. (wheat) and Oryza sativa L. (rice bran) stimulate the hair growth activity and can improve physical activities of aged hair. Shampoo product, which contains 3 kinds of natural extracts, would be used for the treatment for aged hair.

• Journal of the Korean Vacuum Society
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• v.7 no.3
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• pp.221-228
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• 1998

Enhancement of adhesion between polymer films and metal films are obtained by forming the hydrophilic functional groups on the polymer surfaces by ion assisted reaction which uses ion beam in reactive gas environments. In ion assisted reaction, ion dose, blown gas flow rate and ion energy were changed from $5\times 10^{14}$ to $1\times 10^{17}\textrm{ions/cm}^2$, from 0 to 8 sccm, and 0.3 to 1.2 kV, respectively. Wetting angle of water on polymer films modified by $ Ar^+$ ion without blowing oxygen decreases to ~$40^{\circ}$. Contact angle of water on polymer films modified by $ Ar^+$ ion with blowing oxygen decreases to ~$20^{\circ}$, and the surface free energy increases to ~70 dyne/$\textrm{cm}^2$. However, contact angle of water on polytetraflouroethylene (PTFE) modified by ion assisted reaction increases with ion dose. The adhesion strength of metal film deposited on the polymer surface was investigated. In the case of the metal film deposited on the untreated polymers, the metal films are detached from the polymer surface. While, In the case of the metal film deposited on the polymers treated by ion assisted reaction, the metal films are strongly adhere to the polymer surfaces.

• Journal of Korea Technology Innovation Society
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• v.16 no.1
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• pp.252-278
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• 2013

Many countries implement an offset program as a method of the acquisition of modern military technology for enhancement of the domestic military strength. Offset agreements are made based on the value, not a monetary unit. The value should be above minimum threshold fixed by the related regulation. Hence, technology valuation model which is objective and reasonable is required vitally. At present, some defense related organizations such as DTaQ, ADD valuate the proposed technology by using their own method. However, due to the lack of differentiation of valuation analysis indicators for various technologies, existing offset valuation models are inadequate to consider whole characteristics of such technologies. In this paper, we developed four sets of offset valuation analysis indicators considering the characteristics of each technology, parts production, depot maintenance, military equipment performance upgrade, and R&D related technology, by using the Delphi method. Also, we structurized those indicators in each technology by using the factor analysis. Through applying developed indicators, it is expected that technology valuation in the offset program would be more credible and accurate. Ultimately, it gives greater bargaining power to negotiators in the procedure of the offset negotiation.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7229-7235
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• 2013

Background: To determine whether the Health Partner Program is effective in training long-term cancer survivors to be health coaches. Materials and Methods: We randomly assigned cancer survivors who were selected through a rigorous screening process to either the Health Partner Program or the waiting-list control group. The program consisted of 8 weeks of training in health management, leadership, and coaching. At baseline, 8, and 16 weeks, we measured primary outcomes using the Seven Habit Profile (SHP), the Korean Leadership Coaching Competency Inventory (KCCI), Ed Diner's Satisfaction with Life Scale (SWLS), and the Posttraumatic Growth inventory (PTGI) and secondary outcomes using the Hospital Anxiety and Depression Scale (HADS), the Impact of Event Scale-Revised (IES-R), and the Medical Outcomes Study (MOS) short form 36-item questionnaire (SF-36). Results: We recruited 70 subjects and randomly assigned 34 to the intervention group. The Sharpen the Saw habit of the SHP increased significantly more in intervention group than in the control group (p=0.049), as did most PTGI factors. The intervention group also showed a significantly greater enhancement of vitality (p=0.015) and mental health (p=0.049) SF-36 scores but no improvement in KCCI, SWLS, HADS, or IES-R scores. The intervention group also showed a greater clinically meaningful improvement in the "Think Win-Win" of SHP (p=0.043) and in the personal strength score (p=0.025) and total score (p=0.015) of the PTGI. Conclusions: Long-term cancer survivors can benefit from the Health Partner Program to become health coaches.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.3B
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• pp.235-246
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• 2009

The number of industry wireless networks based on IEEE 802.11 WLAN technology deployed in large outdoor work sites, such as freight container terminal, is increasing these days. Wider service coverage, frequent movements of stations and high requirement on service reliability are main characteristics of these networks compared to the conventional IEEE 802.11 networks used in home, office and school. While the importance of these networks Bets higher, we can hardly find previous studies including concrete analysis on these networks based on actual experiments. We carried out several field experiments at a freight container terminal to analyze its IEEE 802.11 network and found out some problematic situations, such as over 50% retransmission rates and frequent disruption of communication link while a station is moving. We explain why these problematic situations happen and suggest some solutions, such as application of mesh technology, smart handoff based on location and movement pattern and adjustment of signal strength and channel allocation. Methods and tools used in the experiments are also detailed in the paper which may be helpful for similar future studies.

• Journal of the Korea Concrete Institute
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• v.15 no.6
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• pp.785-793
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• 2003

This study is intended to analyze the effectiveness of expansive additive, shrinkage reducing agent and combination of the two to reduce the autogenous and drying shrinkage of high performance concrete using mineral admixture such as fly ash, blast furnace slag powder and silica fume. According to results, when expansive additive and shrinkage reducing agent are mixed within an appropriate mixing ratio, fluidity and air content are not influenced, and the enhancement of compressive strength is favorable at the age of 91 and 180days. At the mixing ratio of expansive additive of 5% and 10%, the autogenous and drying shrinkage is reduced by 32∼68% and 25∼49% respectively in comparison with plain concrete. And they are reduced by 18∼34% and 16∼26% respectively at the mixing ratio of shrinkage reducing agent of 0.5% and 1.0%, compared with plain concrete. The mixture of EA-SR combined with expansive additive and shrinkage reducing agent is most effective for reduction of shrinkage. Therefore, it is considered that the using method in combination with expansive additive and shrinkage reducing agent is effective to reduce the shrinkage of high performance concrete using mineral admixture such as fly ash, blast slag powder and silica fume.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.10
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• pp.96-106
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• 2014

Previous academic research on FPGA tools has relied on simple imaginary models for the targeting architecture. As the first step to overcome such restriction, the issues on analytic placement and legalization which are applied to commercial FPGAs have been brought up, and several techniques to remedy them are presented, and evaluated. First of all, the center of gravity of the placed cells may be far displaced from the center of the chip during analytic placement. A function is proposed to be added to the objective function for minimizing this displacement. And then, the density map is expanded into multiple layers to accurately calculate the density distribution for each of the cell types. Early fixation is also proposed for the memory blocks which can be placed at limited sites in small numbers. Since two flip-flops share control pins in a slice, a compatibility constraint is introduced during legalization. Pre-packing compatible flip-flops is proposed as a proactive step. The proposed techniques are implemented on the K-FPGA fabric evaluation framework in which commercial architectures can be precisely modeled, and modified for enhancement, and validated on twelve industrial strength examples. The placement results show that the proposed techniques have reduced the wire length by 22%, and the slice usage by 5% on average. This research is expected to be a development basis of the optimization CAD tools for new as well as the state-of-the-art FPGA architectures.