• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.697-704
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• 2008

This paper presents an analytical prediction of Nonlinear characteristics of prestressed concrete bridges by strengthened of externally tendon considering construction sequence, using unbonded tendon element and beam-column element based on flexibility method. Unbonded tendon model can represent unbounded tendon behavior in concrete of PSC structures and it can deal with the prestressing transfer of posttensioned structures and calculate prestressed concrete structures more efficiently. This tendon model made up the several nodes and segment, therefore a real tendon of same geometry in the prestressed concrete structure can be simulated the one element. The beam-column element was developed with reinforced concrete material nonlinearities which are based on the smeared crack concept. The fiber hysteresis rule of beam-column element is derived from the uniaxial constitutive relations of concrete and reinforcing steel fibers. The formulation of beam-column element is based on flexibility. Beam-column element and unbonded tendon element were be involved in A computer program, named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), that were used the analysis of RC and PSC structures. The proposed numerical method for prestressed concrete structures by strengthened of externally tendon is verified by comparison with reliable experimental results.

• Journal of the Korea Concrete Institute
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• v.25 no.6
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• pp.601-612
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• 2013

In the construction of nuclear power plants using massive walls, the use of high-strength re-bars for shear design is necessary to enhance the constructability and economy. In this study, low-rise walls (aspect ratio of 1.0) with grade 550 MPa bars were tested under cyclic loading to investigate the shear capacity and deformation capacity. The test parameters were the grade of horizontal re-bars (550 MPa, 420 MPa), strength of concrete compressive strength (46 MPa, 70 MPa), horizontal/vertical reinforcement ratio, use of lateral confinement hoops, shape of cross section, and failure modes (shear failure before or after flexural yielding). The test results were compared with those of walls with grade 420 MPa bars and predicted strength by current design codes. The results showed that the shear strength of the walls with 550 MPa bars was comparable to that of the walls with 420 MPa bars though the safe margin slightly decreased. ACI 349 provides underestimated shear strength for the walls with 550 MPa bars. In case of the wall with flexural yielding, a large deformation capacity was achieved. This result indicates that the ACI 349 provisions can be safely applied to seismic design of the low-rise walls (aspect ratio of 1.0) with grade 550 MPa bars.

• Journal of Environmental Policy
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• v.12 no.3
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• pp.3-20
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• 2013

Recently, impacts and damages of extreme climate change have already affected on worldwide. Thus adaptation and action plan are essential concepts in minimizing the impacts of climate change. In order to introduce climate change adaptation decision-making measure, the need for high-quality and integrated information system within adaptation policy has increased enormously. However, most of adaptation information is based on different sources and various backgrounds. Currently, domestic climate change information is disseminated from about 132 internet sites and most of them are limited to general information of climate change, rather than information that are based on scientific evidence. Also, there are some difficulties in updating new resources. Reliable climate change information is provided from different agencies, which makes users difficult to locate right information they need. As a progress to overcome the limitations of these problems, we carried out a feasibility research on integrated information system for climate change adaptation. For the objectives, our solutions are as follows. First, we analyzed definition of climate change adaptation and climate change adaptation information. Second, we suggested integrating the information system for adaptation and phased implementation plan for establishing integrated information system for climate change. Finally, we verified the establishment of integrated support system based on policy applications of integrated information system. This system will provide an integrated climate change information and be a very useful tool to support the decision making process of effective climate change adaptation policies.

• Journal of the Korean Geotechnical Society
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• v.19 no.4
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• pp.145-153
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• 2003

The resonant column testing determines the shear modulus and material damping factor dependent on the shear strain magnitude, based on the wave-propagation theory. The determination of the dynamic soil properties requires the theoretical formulation of the dynamic behavior of the resonant column testing system. One of the theoretical formulations is the use of the wave equation for the soil specimen in the resonant column testing device. Wood, Richart and Hall derived the wave equation by assuming the linear elastic soil, and didn't take the material damping into consideration. Hardin incorporated the viscoelastic damping of soil in the wave equation, but he had to assume the material damping factor for the determination of the shear modulus. For the better theoretical formulation of the resonant column testing, this study derived a new wave equation to include the viscosity of soil, and proposed an approach for the solution. Also, in this study, the equation of motion for the testing system, which is another approach of the theoretical formulation of the resonant column testing, was also derived. The equation of motion leads to the better understanding of the resonant column testing, which includes the dynamic magnification factor and the phase angle of the response. For the verification of the proposed equation of motion for the resonant column testing, the finite element analysis was performed for the resonant column testing. The comparison of the dynamic magnification factors and the phase angles far the system response were performed.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.512-518
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• 2015

Pine wilt disease (PWD) caused by pine wood nematode, Bursaphelenchus xylophilus, has become the most serious threat to pine trees in Korea. This study was subjected to investigate effective biological control agent against PWD. To select nematocidal bacteria against PWD, Bacillus licheniformis MH48 was selected among five bacteria due to its high nematocidal potential. B. licheniformis MH48 was tested for cell growth and protease activity to evaluate its nematicidal potential. In the B. licheniformis MH48, cell numbers were highest three days after incubation, while protease activity was highest after seven days. In the effect of different concentrations of B. licheniformis MH48 culture broth against B. xylophilus, 20% concentration of culture broth showed approximately 80% of pine wood nematode mortality compared to the control. Especially, pine wood nematode's cuticle layers were degraded two days after treatment of B. licheniformis MH48 culture broth. The present study suggests that B. licheniformis MH48 can be one of the potential biocontrol candidates against pine wood nematode due to its ability to produce protease.

• Journal of the Korean GEO-environmental Society
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• v.17 no.7
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• pp.35-42
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• 2016

There are many reclamation projects domestically and internationally which requires large quantity of reclaimable materials. To provide enough reclaimable soils which are limited in land, there have been various research focusing on the dredged soils in the marine environments. As a part of this research, a GIS based 3D dredging reclamation visualization program was developed for the volume estimation of dredged soils in 2015. The developed program is based on the digitized spatial information of the site investigation data with a consideration of the reliability of the data. Prior to the validation with the comparisons with the actual dredged volume measurement data, the developed program was compared with the commercial 3D visualization program with 3D visualized results from the test site near the Gunjang harbor. The validation of the developed program was performed in terms of the degree of visualized precision, the sectional and profiling of soil layers and the dredged volume estimation results. Based on the comparisons, both commercial and developed program show similar dredged volume with minor discrepancies in soil layers.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.3
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• pp.29-38
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• 1990

A totally, new approach of Lagrangian formulation named 'Pseudo Lagrangian Formulation(PLF)' for large deformation analysis of continue and structures by the finite of element method has been presented, and the efficiency and accuracy of nonlinear analysis beam element formulated by PLF has been discussed by solving several numerical examples. In PLF, the deformation of a body is maeasured by assigning a nonphysical 'Pseudo' configuration as reference. The Lagrangian deformation and the finite element mapping of the traditonal Lagrangian approaches are then carried out directly at the same time, The result of numerical tests shows superior performance of PLF to the traditional Lagrangian methods, Applications of PLF to small and finite deformation problems indicate that PLF not only serves as an alternative but has certain implementational advantages over total or updated Lagrangian formulations.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.2
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• pp.43-54
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• 1992

For shallow arches with large dynamic loading, linear analysis is no longer considered as practical and accurate. In this study, a method is presented for the dynamic analysis of shallow arches in which geometric nonlinearity must be considered. A program is developed for the analysis of the nonlinear dynamic behavior and for evaluation of critical buckling loads of shallow arches. Geometric nonlinearity is modeled using Lagrangian description of the motion. The finite element analysis procedure is used to solve the dynamic equation of motion and Newmark method is adopted in the approximation of time integration. A shallow arch subject to radial step loads is analyzed. The results are compared with those from other researches to verify the developed program. The behavior of arches is analyzed using the non-dimensional time, load, and shape parameters. It is shown that geometric nonlinearity should be considered in the analysis of shallow arches and probability of buckling failure is getting higher as arches are getting shallower. It is confirmed that arches with the same shape parameter have the same deflection ratio at the same time parameter when arches are loaded with the same parametric load. In addition, it is proved that buckling of arches with the same shape parameter occurs at the same load parameter. Circular arches, which are under a single or uniform normal load, are analyzed for comparison. A parabolic arch with radial step load is also analyzed. It is verified that the developed program is applicable for those problems.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.210-218
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• 2016

Recently, as service design was introduced to improve the quality of public service, there have been many attempts to improve various public service. In the process, various stakeholders including general citizens are participating in the design improvement activity through a method of design service but the parties are facing a difficulty in the progress because of a limitation of time and budget and a lack of professionalism among the member while the parties are planning the process and activities based on the professional service design method. Persona method that is usually used in the process of service design is encountering a limitation as well. Also, there are continuous attempts to understand the limitation of persona and apply an alternative research method among service and UX designers. For this reason, this thesis is to recognize the limitation in deduction method of traditional persona and suggests a fast and economical production method of Rapid Persona speaking for the goal of users and overcoming the limitation. Furthermore, by applying the suggested method of making Rapid Persona to an actual public service design project of National Statistical Office, the test through an empirical study was conducted. This was conducted with the purpose of progressing a discussion in the respect of actual application beyond a banal discussion. Through the research method suggested in this study, it is expected to overcome the limitation of time and a lack of professionalism and, based on these, can be used in the process of various service design and UX design as establishing persona in a fast and easy way.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.722-731
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• 2016

Previous findings on Organizational Citizenship Behaviors is a useful index for effectiveness of the organization. Also, it is a factor that explains the relation between its member's attitude and behavior as organizational commitment had been stabilized. Since autonomy and rapidity has become more important in increasing the efficiency of the organization, this means Organizational Citizenship Behaviors has become important in it. Organizational Citizenship Behaviors of the members occurs only when discretion and autonomy are given to its members. Therefore, this study aimed at measuring the effects of police officer's personal dispositions on organizational citizenship behaviors, exploring the moderation effect of organization culture, and providing the basis with implications to promote the Organizational Citizenship Behaviors in the police Organization. By reviewing previous finding, Police Officer's Personal Dispositions were selected as independent variables, Organizational Citizenship Behaviors was selected as dependent variable. and Organizational Culture was selected as moderation variable. The result of analysis showed that The belief & The Norm influenced in Organizational Citizenship Behaviors(positive), and The Value in Organizational Citizenship Behaviors(negative). And The moderation effect was tested: The Value${\rightarrow}$Hierarchical Culture${\rightarrow}$Organizational Citizenship Behaviors(negative), The belief${\rightarrow}$Rational Culture${\rightarrow}$Organizational Citizenship Behaviors(negative)