• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.2
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• pp.122-129
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• 2017

The aim of this study is a large amount use of recycled aggregates. The considering recycled aggregates replacement ratio is 50% that of natural aggregates. In order to increase the shear capacity of beams, that may be weaken by use of recycled aggregates, steel fibers are reinforced. The main variables are steel fiber volume fractions such as 0%, 0.5%, 0.75% and 1.0%. After the test, it could confirm that the strength and deformation capacity of beams with the steel fiber content values of 0.5% and 0.75% are comprehensively enhanced compared to non reinforcement. After evaluating the shear strength by using shear strength equations of previous researches, it concluded that the strength equation of Oh et al. (2008) is able to predict the shear strength of SFRC beams on the safety side.

• Korean Journal of Adult Nursing
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• v.14 no.1
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• pp.83-92
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• 2002

Purpose: This study was performed to identify the process of change, decisional balance and self-efficacy corresponding to the stage of exercise behavior using Transtheoretical Model in patients with type 2 diabetes mellitus. Method: The study method was a survey in 100 type 2 DM patients at out-patients clinic of Y medical center from March 19, 2000 to October 30, 2000. Result: The results were as follows: The subjects were divided into five stages of exercise behavior ; 15.0% in pre-contemplation stage, 33.0% in contemplation stage, 17.0% in preparation stage, 16.0% in action stage and 19.0% in maintenance stage. The subjects in pre-contemplation stage used all processes of change in the least. "Dramatic relief(DR)", "Environmental reevaluation(ER)" and "Self reevaluation(SR)" were identified as main processes of change in contemplation stage. "Consciousness raising(CR)", "DR" were used higher than average in preparation stage. Helping relationships(HR)", "CR", "ER", "SR", "Social liberation(SL)", "Counter conditioning (CC)", "Reinforcement management(RM)", "Self iberation(SEL)" and "Stimulus control(SC)" were used higher than average in action stage. The subjects in maintenance stage used all process of change the highest except "DR"and "HR". "Cons" score of decisional balance was the highest in pre-contemplation stage, "Pros" score was the highest in action stage and "Self-efficacy" score was the highest in maintenance stage. Conclusion: This study can provide the basis of staged matching exercise program using TTM for more effective and useful intervention.

• Journal of the Korea Concrete Institute
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• v.15 no.5
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• pp.697-704
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• 2003

The purpose of this experimental study is to investigate the relationship of the shear behavior and the variety of width, depth and location of an opening in reinforced concrete deep beams with rectangular web openings, and to present an improved shear strength equation of those members. The main parameters considered were concrete strength(fck), shear span-to-overall depth ratio(a/h), and the size and vortical position of the web openings. Twenty five deep beams were tested under two symmetric loading-points. Test results showed that the shear behavior of deep beams with web openings was influenced by a/h and the size of opening. In addition, the KCI shear design provision is a tendency to be more unconservative according to the increase in a/h and the area-ratio of opening to shear span(Ao/Ash). Based on the concrete strut action of top and bottom member of an opening and the tie action of longitudinal reinforcement, a proper design equation which closely predicts the capacity of deep beams with rectangular openings is developed.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.2
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• pp.12-27
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• 2003

The purpose of this study is to look for an environmental design method based on open narrative structure, and to promote various experiences and interpretations of space through user's engagements. That is to say, the designer does not lead specific events through separate Boning but using the continuous open composition users are provided with margins for their imaginations. Spatial formulation through open narrative structure gives us various thoughts and it plays an important role in making a sequential space. Like an abstract painting, it is a complex story making or arranging a montage of images containing stories that elicit the reader's engagement through diverse interpretations. Like this, open composition exists in an ambiguous state and it is possible to interpret unfinished‘evolving work’within it. Utilizing open narrative structure, this study attempts to apply the idea of sequencing and open composition in the case of designing Arirang Culture Park. Open composition should induce various engagements by users and could be a medium which organically connects nature, culture and people. The spatial strategies of‘ambiguity’ and‘transparency’are like a bundle of complex and heterogeneous factors. Finally, the study focuses on the ‘integration’of the main ideas that compose multilayered space. ‘Voidness’and‘thickening’are also used for spatial strategies in open narrative structure. As alternative plans for undecided programs of the space, the voidness can be a strategic design program with flexibility about changes of futures. Also, thickening can be a strategic design program for functional reinforcement of the space, for the dramatic effects and for the generation of incidental events. Although both voidness and thickening seem paradoxical, we can see they are similar in the way that both focus on various spatial uses and by how they do not function as one-to-one correspondence, but as multiple correspondences. Therefore, open narrative structure is possible to apply in designing space and it can be an alternative design strategy for inducing multiple interpretations of space.

• Journal of Engineering Education Research
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• v.21 no.1
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• pp.27-36
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• 2018

This study aims to deduce operational implication of R-WeSET program through women students in science & engineering and companies's perception and assessment on the basis of NCS key competency. The significant results are as follows. Firstly, companies and women students in science & engineering share a similar perception on importance of NCS key competencies. The programs should be reviewed and improved for women students who are truly aware of companies' needs. Secondly, the main areas of NCS key competency that are poor in companies' perception are 'positive thinking & drive', 'creativity & challenge spirit', 'communication skills' and 'problem-solving skills'. To enhance these weak skills, activating the actual programs such as "Convergence Design Camp", "Field Adaptability Improvement" and developing the new communication program are required. Lastly, most of women students have attained the satisfying result from "Field Competency Reinforcement Program". Especially, "Industry Field Training" shared the great progresses on all skills of key competency, hence why the progressive model should be developed in the future. This study figures out who's the right person for the 4th Industrial Revolution era, producing a meaningful result in order to change in the higher education system of women students and to grow human resources who will contribute to the community and company.

• Tribology and Lubricants
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• v.36 no.4
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• pp.215-231
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• 2020

The paper presents extensive survey and review of experimental and analytical researches on fluid film bearings and squeeze film dampers (SFDs) for turbomachinery available in open literature (major archival international journals) published recently (2018 and 2019 only). Over 60 published research works are reviewed based on the research topics and objectives, the types of bearings, size of bearings, and main design parameters with a brief summary of experiments and/or predictions in each work. Some important findings and general observations about the experimental and/or predictive data are also presented. There are several major trends observed throughout the survey. A large portion of the papers focuses on bearing surface textures and effect of operating and assembly conditions on static and/or dynamic forced performances, as well as bearing surface roughness and wear patterns. Researches on geometry of orifices and recesses in hydrostatic (or hybrid) bearings, as well as bearing system stability predictions using thermohydrodynamic analysis and computational fluid dynamics (CFD), are considered as significant topics. Studies on SFDs mainly focus on experimental identification of force coefficients for various SFD geometries and sealing conditions. Reliable experiments of fluid film bearings and SFDs along with the development of experimentally benchmarked predictive tools enable reinforcement of the path for reliable implementations of the bearing components into high performance rotating machinery operating at extreme and harsh conditions. The extensive list of sources of recent experiments in the available open literature is a welcome addition to the analytical community to gauge the accuracy of predictive tools.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.519-526
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• 2010

The construction site for $\bigcirc\bigcirc$ transformer substation was located at a mountain valley. In order to prepare the site, the valley was first filled with crushed rock debris up to 63m. Since the main concern of this project is to minimize differential settlement of the foundation of transformer facilities, dynamic compaction was performed every 7m followed by reinforcement with EMP(Ez-Mud Piling). The EMP is one of bored piling methods, in which a hole is bored by means of air percussion and maintain by injecting Ez-Mud. Then a PHC pile (Pretensioned spun High strength Concrete pile) is embedded and finalized with a hammer. In this study, bearing capacities and long term behavior of a pile installed by EMP were investigated. To achieve these objectives, a series of tests such as static and dynamic load tests were conducted. In addition, a construction quality control standard was proposed based on the test results.

• Journal of the Korea Concrete Institute
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• v.13 no.5
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• pp.499-506
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• 2001

Eight direct tension tests were conducted to study the bond characteristics and crack behavior in high-strength concrete axial members. The main variable was the concrete strength up to 61-63 MPa. The specimens consisted of two different types of the short specimens modeled the part between transverse cracks and the long specimens having numerous transverse cracks. The results obtained show that the bond strength increases in proportion to compressive strength. Thereby, in high-strength concrete the length of stress-disturbed region is shortened and the space of adjacent transverse cracks become smaller. Although the concrete strength varies from 25 MPa to 61 MPa, the split cracking loads remain constant, while transverse cracking loads vary as variation of concrete tensile strength. Accordingly, the current code provisions for development length may need reconsideration in high-strength concrete members, and it is recommended that either thicker cover or transverse reinforcement should be additionally provided for high-strength concrete members.

• Journal of Ocean Engineering and Technology
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• v.28 no.1
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• pp.20-27
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• 2014

In view of the importance of material reduction and rational structural design due to the rapid increase in oil and steel prices, an optimized structural hybrid design system for the doubler plate of a ship's hull structure was developed. A direct design process by a structural designer was added to this developed optimized system to increase the design efficiency and provide a way of directly inserting a designer's decisions into the design system process. As the first step of the doubler design system development, the design formulas used in doubler design system were introduced. Based on the introduction of influence coefficients $K_{t_c}$ $K_{t_d}$, $K_{b_d}$ and $K_{a_d}$ according to the variations in the doubler length, breadth, doubler thickness, and average corrosion thickness of the main plate, the design formulas for an equivalent plate thickness were developed, and a hybrid design system using these formulas was suggested for the slender doubler plate of a ship structure subjected to a longitudinal in-plane compression load. By using this developed design system, a more rational doubler plate design can be expected considering the efficient reinforcement of the plate members of ship structures. Additionally, a more detailed structural analysis through local strength evaluations will be performed to verify the efficiency of the optimum structural design for the doubler plate.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.1 s.108
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• pp.71-80
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• 2005

In order to search for ecologically indicative characteristics on the street tree plots in Daegu area, plant communities and their floras were investigated. A total of 105 plots were collected and numerically analyzed by PCoA(Principal Coordinates Analysis). These plots were classified into 4 types containing 139 species, 97 genera, 42 families(including 37 exotic species): urban-dry type, urban-wet type, rural-dry type, rural-wet type. Habitat connectivity to the surrounding vegetation cover, extent and frequency of human impacts, and soil moisture recognizably were the main factors to allow the plots differentiation. Indicative species composition to these four types was generated as Eleusine indica-Eragrostis multicaulis-Oxalis corniculata to the urban-wet, Digitaria ciliaris-Eleusine indica-Eragrostis multicaulis to the urban-dry, Setaria viri-dis-Artemisia-Lactuca indica var. laciniata to the rural-wet, and Setaria viridis-Digitaria ciliaris-Erigeron canadensis to the rural-dry, respectively. Mean species number per plot for rural type was 2.5 times higher than for urban types. Street tree species representative to the rural-wet type is Zelkova serrata, which is a key species of potential natural vegetation in the alluvial land of Daegu area. Street tree plots were characterized by Eleusine indica showing the highest r-NCD value and also C4-assimilation grass plants. Views on the efficacy of the rural-wet type and the reinforcement of vegetation connectivity and soil moisture in rehabilitating street tree plots, are discussed.