• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.5
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• pp.148-160
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• 2012

This study proposed more reasonable prediction models on compressive strength and carbonation of concrete structure and developed a more effective tunnel safety diagnosis and maintenance method through field application of the proposed prediction models. For this study, the Seoul Metro's Line 1 through Line 4 were selected as target structures because they were built more than 30 years ago and have accumulated numerous diagnosis and maintenance data for about 15 years. As a result of the analysis of compressive strength and carbonation, we were able to draw prediction models with accuracy of more than 80% and confirmed the prediction model's reliability by comparing it with the existing models. We've also confirmed field suitability of the prediction models by applying field, the average error of an estimate on compressive strength and carbonation depth was about 20%, which showed an accuracy of more than 80%. We developed a more effective maintenance method using durability prediction Map before field inspection. With the durability prediction Map, diagnostic engineers and structure managers can easily detect the vulnerable points, which might have failed to reach the standard of designed strength or have a high probability of corrosion due to carbonation, therefore, it is expected to make it possible for them to diagnose and maintain tunnels more effectively and efficiently.

• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.83-92
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• 2017

This paper deals with numerical analysis of behavior of curved mechanically stabilized earth(MSE) walls with geosynthetics reinforcement. Unlike typical concrete retaining walls, MSE wall enables securing stability of higher walls without being constrained by backfill height and is currently and widely used to create spaces for industrial and residential complexes. The design of MSE walls is carried out by checking external stability, similarly to the external checks of conventional retaining wall. In addition, internal stability check is mandatory. Typical stability check based on numerical analysis is done assuming 2-dimensional condition (plane strain condition). However, according to the former studies of 3-dimensional MSE wall, the most weakest part of a curved geosynthetic MSE wall is reported as the convex location, which is also identified from the studies of the laboratory model tests and field monitoring. In order to understand the behaviour of the convex location of the MSE wall, 2-dimensional analysis clearly reveals its limitation. Furthermore, laboratory model tests and field monitoring also have restriction in recognizing their behaviour and failure mechanism. In this study, 3-dimensional numerical analysis was performed to figure out the behaviour of the curved part of the geosynthetic reinforced wall, and the results of the straight-line and curved part in the numerical analysis were compared and analysed. In addition, the behaviour characteristics at each condition were compared by considering the overburden load and relative density of backfill.

• The Journal of the Korea Contents Association
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• v.8 no.9
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• pp.101-114
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• 2008

This study has been carried out in an effort to bring light on the job scope which is required among the fashion models in Korea, then to sort out the concrete items of job pursuant to the job scope for the systemization of them. For this study, ten models who majored a fields of industry and the college in Korea, have gathered to analyze the job of the fashion models using the DACUM. As a result of it, the jobs of the fashion models have been classified into 7 duties and subsequent 86 tasks, while the fashion models entry jobs have been divided into 32 tasks(37.21%) that are necessary in the college before appointment. The result of analysis which investigates the relation between the significancy, the degree of difficulty and the frequency of the business, has it that the number of high-significancy business rises to 46 tasks(53.49%), high degree of difficulty business reaches to 21 tasks(24.41%), high frequency business is 18 tasks(20.93%), high degree of significancy and difficulty business stands at 13(15.12%), high significancy and frequency business amounts to 16 tasks(18.60%), and high degree of significancy, difficulty and frequency business reaches to 7 tasks(8.14%) respectively. These results should be actively reflected on the college curriculum before appointment, and on the job retraining courses for the incumbent fashion models, so as to enhance their job competency.

• The Journal of the Korea Contents Association
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• v.15 no.2
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• pp.151-162
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• 2015

A theme park is a complex space, in which held is a performance & exhibition event created to make visitors feel fun and a deep impression through a certain theme. Recently, local governments are increasingly planning for theme parks with the aim of local economy revitalization. Accordingly, this paper set up a development model for a Korean culture theme park after deducting success factors for creating a successful theme park through the case of Korean culture theme park. To be concrete, this paper deducted the success factors through literature research and case research as follows: Setting of themes having identity and consistency; programs that can give fun and a deep impression; convenient support facilities reflecting customers' needs; differentiated marketing for progress in customer attraction power; location linked with cultural resources around a theme park and a space for communicating a message; privately-initiated project promotion and the main body of operation; target setting consequent on market segmentation, and demand forecast, etc. A theme park cannot be successfully operated to contribute to local economy revitalization until such success factors should be closely linked and harmonized with each other. In addition, in order for a theme park to make a continued growth, it's required that problems occurring at the operational stage should be endlessly improved, and contents strengthening should be continuously done in line with circumstances of the times and viewers' eye level.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.1
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• pp.64-71
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• 2016

In this paper, when the composite beam is made with UHPC deck and steel girder, the steel girder takes the form of the inverted-T shape without top flange because of high strength and stiffness of UHPC deck. There is no evaluation by experiment and analysis about the shear connector behavior on the web of steel girder and flexural behavior of inverted-T shape composite beam. By this reason, this study compares between experiment and analysis by using tension softening model of UHPC on the basis of flexural test results of 16 members considering compressive strength of UHPC, spacing of stud and thickness of deck as variables. The results of tensile strength of UHPC by inverse analysis were 6.57 MPa(in case of 120 MPa) and 9.57 MPa(in case of 150 MPa). In case of the test members with small stud spacing, the results of analysis and test were close clearly, and the test members with thick deck and low UHPC compressive strength also similar, but effects were small. As it compared between analysis and experiment totally, the results of analysis and experiment agree well. So the tension softening model of UHPC is reasonably reflected on the real behavior of composite beam of UHPC.

• Journal of Korean Academy of Nursing
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• v.23 no.3
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• pp.369-376
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• 1993

Since nursing has come of age both as a profession and as a scholarly discipline, there has been increasing concern with delineating its theory base. In 1978 Chinn and Jacobs asserted that “the development of theory is the most crucial task facing nursing today.” The basic building blocks of theories are concepts. Concept formation begins in infancy, for concepts help us to categorize and organize our environmental stimuli. Concepts help us to identify how our experiences are similar or equivalent by categorizing all the things that are alike about them. concepts can be primitive, concrete, or abstract. Concept Analysis is a strategy that examines the attributes or characteristics of a concept. It is a formal, linguistic exercise to determine those defining attributes. It encourages communication. Its basic purpose is to distinguish between the defining and irrelevant attributes of a concept similarities. It is a process of determining the differences between concepts and it is useful for several reasons. It is an excellent way to begin examining information in preparation for research or theory construction and results in an operational definition and a list of defining attributes and antecedents. It provides the scientist with an excellent beginning for a new tool, is an excellent way of evaluating an old one and is useful in evaluating existing instruments. The steps of concept analysis are : 1. Select a concept, 2. Determine the aims or purposes of the analysis, 3. Identify all uses of the concept that you can discover, 4. Determine the defining attributes, 5. Construct a model case, 6. Construct borderline, re-lated, contrary, invented, and illegitimate cases, 7. Identify antecedents and consequences, 8. Define empirical referents. In this paper, the concept selected for analysis was Love. The concept of love is of great interest to nursing because loving care is considered vital to the nursing care of patients. The aims of the concept analysis of love were to clarify the meaning of love, to develop an operational definition for it and to contribute to existing nursing theory. Love influences the quality of life which is the goal of nursing according to Parse in her Human Becoming Theory. Lived experiences are the entities for study in Parse's Research Methodology. Human caring, human understanding, and human becoming are the most important issues in lived experiences. In this research, dictionaries and literature from nursing philosophy and other human disciplines were used to identify the concept of love. As many different instances of the concept as could be found were examinned. The model case was a real life example of the use of the concept. Next borderline, related, invented, and contrary cases were constructed for the purpose of providing examples of “not the concept” and for promoting further understanding of the concept being discussed. The defining attributes of the concept of love were concern, responsibility, respect, understanding and dedication. Love was defined as showing concern and understanding. relating with mutual respect and dedicating oneself responsibly to others. Concept analysis is a highly creative activity and may add significant new information to a given area of interest. It is a strategy for developing a concept based on observation or other forms of empirical evidence. The purpose of concept analysis is to generate new ideas. It provides a method of examining data for new insights that contribute to theoretical development. This concept analysis suggests that a nurse’s love for patients is shown in the process of giving oneself in mutual relationships of responsibility and respect and in continuously providing understanding and quality human care for them.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.5
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• pp.215-226
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• 2018

In this paper, to estimate the dynamic behavior of a submerged floating tunnel(SFT) by underwater explosion(UE), the SFT is modeled and analyzed by the explicit structural analysis package LS-DYNA. The section of SFT near to explosion point is modeled to shell and solid elements using elasto-plasticity material model for concrete tubular section and steel lining. And the other parts of the SFT are modeled to elastic beam elements. Also, mooring lines are modeled as tension-only cable elements. Total mass of SFT is including an added mass by hydrodynamic effect. The buoyancy on the SFT is considered in its initial condition using a dynamic relaxation method. The accuracy and the feasibility of the analysis model aree verified by the results of series of free field analysis for UE. And buoyancy ratio(B/W) of SFT, the distance between SFT and an explosion point and the arrangement of mooring line aree considered as main parameters of the explosion analysis. As results of the explosion analysis, the dynamic responses such as the dent deformation by the shock pressure are responded less as more distance between SFT and an explosion point. However, the mooring angle of the diagonal mooring system can not affect the responses such as the horizontal displacement of SFT by the shock pressure.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.791-800
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• 2013

Needs for developing a better way of cost estimating process for public construction projects have been widely recognized. Those needs are mainly from the early phases of the project through the construction life cycle due to the its importance to the control process. In contrast to the traditional estimating method based on unit-price references, this research utilized this following process. The first step is analyzing the real cost data from actual cost activities (2000~2010) about the statement of P.S.C(Prestressed Concrete) Box Girder Bridge. The collected data was broken into four categories based on technical construction methods such as I.L.M(Incremental Launching Method), M.S.S(Movable Scaffolding System), F.S.M(Full Staging Method), and F.C.M(Free Cantilever Method). The second, actual design documents including the actual cost estimating documents, drawings and specifications were carefully reviewed to cluster the cost itemized statement from four categories. It was also attempted to seek the proper breakdown of standard works that are responsible for more than 95 percentage in each categories in terms of its cost. The third, this research comes up the index for standard unit materials and unit price of standard work and develops the approximate estimating model applying for the specification(length and breadth of bridges) per square area that the user takes as well as suggests the practical application plan within the original time alloted.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.1
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• pp.81-94
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• 2010

This paper deals with the fracture simulation of UHPFRC girder with the interface type model. Based on the existing numerical simulation of quasi-brittle fracture in normal strength concrete, constitutive modeling for UHPFRC I-girder has been improved by including a tensile hardening at the failure surface. The finite element formulation is based on a triangular unit, constructed from constant strain triangles, with nodes along its sides and neither at the vertex nor the center of the unit. Fracture is simulated through a hardening/softening fracture constitutive law in tension, a softening fracture constitutive law in shear as well as in compression at the boundary nodes, with the material within the triangular unit remaining linear elastic. LCP is used to formulate the path-dependent hardening-softening behavior in non-holonomic rate form and a mathematical programming algorithm is employed to solve the LCP. The piece-wise linear inelastic yielding-failure/failure surface is modeled with two compressive caps, two Mohr-Coulomb failure surfaces, a tensile yielding surface and a tensile failure surface. The comparison between test results and numerical results indicates this method effectively simulates the deformation and failure of specimen.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.4
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• pp.289-296
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• 2014

The rebar detailing is an important work influencing the final performance and quality of RC structures. But it is one of the most irrational and illogical activity in construction site. Many groups of workers, including main contractors, structural engineers, shop drawers, rebar fabricators, and etc., participate in this activity. A loosely-organized process for this activity is apt to produce a big amount of rebar loss or even degraded structures. A 3-dimensional rebar auto-placing system, called as Rebar Hub, has been designed and implemented in this research. Rebar Hub provides a totally integrated service from 3D structural modeling of buildings to rebar auto-placing considering anchorage, splice, and the length of ordered rebar. In addition, Rebar Hub can recognize the 2D drawing CAD files and then build 3D structural models which are used for the start point of 3D rebar auto-placing. After rebar auto-placing, each members of the 3D structural model have rebar information belonging to them. It means that the rebar information can be used for the afterward works such as quantity-survey, manufacturing and fabrication of rebars. Rebar Hub is showing outstanding performance while applying to practical projects. It has almost five times productivity and reduces the rebar loss up to 3~8% of the initially-surveyed amount of rebar.