• Bulletin of the Society of Naval Architects of Korea
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• v.52 no.2
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• pp.19-24
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• 2015

A reliable assessment and analysis of the condition of high pressure and temperature steam pipelines requires defining stress state, which will take into consideration not just the impact of internal pressure and temperature but all applied loads. For that, usage of modeling and numerical methods for calculation and analysis of stress state is essential. The main aim of piping stress analysis is to check the design of piping layout, which will allow simple, efficient and economical piping supports and provide flexibility to the piping system for loads and stresses. The piping stress analysis is carried out using CAESER II software. By using this software we can evaluate stresses, stress ratios, flange condition, support loads, element forces and displacements at each node and points. In this paper, only the maximum and minimum displacement results are tabulated, which is also shown in detail by an example of main steam pipelines of UST Main Engine System [1].

• Journal of Korean Society of Steel Construction
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• v.25 no.3
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• pp.307-320
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• 2013

This paper proposes a new hybrid support structure by the driven piles which removes disadvantages of the existing type of support structure for offshore wind turbines. The hybrid type of support structure is combined with concrete cone and steel shaft, and is supported not only by gravity type foundations but also by driven piles. For three dimensional analysis of the huge and thick concrete structure, a solid-shell element that is capable of exact modeling and node interpolations of stresses is developed. By applying wave theory of stream function and solid-shell element in XSEA simulation software for fixed offshore wind turbines, a quasi-static analysis and natural frequency analysis of proposed support structure are performed with the environmental condition on Southwest Coast in Korea. In the result, lateral displacement is not exceed allowable displacement and a superiority of dynamic behavior of new hybrid support structure is validated by natural frequency analysis. Consequently, the hybrid support structure presented in this study has a structural stability enough to be applied on real-site condition in Korea. The optimized structures based on the preliminary design concept resulted in an efficient structure, which reasonably reduces fabrication costs.

• Journal of the Korea Computer Graphics Society
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• v.1 no.2
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• pp.201-212
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• 1995

This paper presents a new method of dynamics-based synthesis of bipedal, especially human, walking. The motion of the body at a time point is determined by ground reaction force and torque under the support foot and joint torques of the body at that time point. Motion synthesis involves specifying conditions that constrain ground reaction force and torque, and joint torques so that a given desired motion may be achieved. There are conditions on a desired motion which end-users can think of easily, e.g. the goal position and orientation of the swing foot for a single step and the time period of a single step. In this paper, we specify constraints on the motion of the support foot, which end-users would find difficult to specify. They are constraints which enforce non-sliding, non-falling, and non-spinning the support foot. They are specified in terms of joint torques and ground reaction force and torque. To satisfy them, both joint torques and ground reaction force and torque should be determined appropriately. The constraints on the support foot themselves do not give any good clues as to how to determine ground reaction force and torque. For that purpose, we specify desired trajectories of the application point of vertical ground reaction force (ground pressure) and the application point of horizontal ground reaction (friction) force. The application points of vertical pressure and friction force are good control variables, because they are indicators to kinds of walking motions to synthesize. The synthesis of a bipedal walking motion, then, consists of finding a trajectory of joint torques to achieve a given desired motion, so that the constraints are satisfied under the condition of the prescribed center of pressure and center of friction. Our approach is distinguished from many other approaches, e.g. the inverted-pendulum approach, in that it captures and formulates dynamics of the support foot and reasonable constraints on it.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.2
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• pp.15-21
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• 2010

Structural analysis used to evaluate the load carrying capacity of a bridge should implement behavioral characteristics similar to the actual behaviors of the structure through loading tests, but it is not feasible in many cases due to the behavioral characteristics of points, inadequate modeling method in structural analysis, errors in loading tests, changes in strength and rigidity resulting from cross-sectional damage, etc. This problem can be more serious if bridge bearings have been damaged or were not installed and, consequently, the bearings do not function properly. This study produced results similar to actual behaviors using a structural analysis model built with support moment derived from the difference $\Delta{\delta}$ between measured deflection obtained by confining the cantilever segment of a solid beam and calculated deflection under a unrestrained condition. When the load carrying capacity of a bridge in operation was evaluated in consideration of the confinement condition of supports, the result was 15~19% lower than load carrying capacity calculated by the existing method.

• Korean Journal of Social Welfare Studies
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• v.48 no.4
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• pp.91-120
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• 2017

This study aimed (a) to examine the association between chronic illness and multidimensional disability(i.e., psychological/emotional functions, activity capacity, and participation frequency) among older adults with disabilities, (b) to investigate the effect of formal and informal supports on multidimensional disability, and (c) to analyze the moderating effects of formal and informal supports on the association between chronic illness and multidimensional disability. This study used 2014 Korea Welfare Panel Study(the 9th wave) data and 450 older adults with disabilities aged 50 and over were selected as the study target. The research model was analyzed by structural equation modeling using IBM AMOS 22.0. Based on the ICF framework developed by WHO, health condition was measured by the level of chronic illness; psychological/emotional functions were measured by health satisfaction, self-esteem, and depression; activity capacity was measured by ADLs and IADLs; participation frequency was measured by the total number of social activities joined; formal support was measured by the total number of formal welfare services for people with disabilities utilized; informal support was measured by perceived social support. The findings showed that the level of chronic illness was negatively associated with psychological/emotional functions among the older adults with disabilities. The informal support positively affected psychological/emotional functions and activity capacity, whereas the formal support showed the opposite result. That is, the formal support negatively influenced activity capacity and showed a moderating effect on the association between the level of chronic illness and the psychological/emotional functions in a reverse way. Based on the results, practice and policy implications for alleviating disability level among the older adults with disabilities were discussed.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.1
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• pp.21-30
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• 1998

Design parameters which used to analyze the stress distribution on the tank wall were defined to develop the propellant tank and obtain optimal values. 1/4 modeling of total tank was selected to calculate the stress distribution with respect to the variation of the support lug location and the tank wall thickness and 1/2 modeling was selected for the stress distributions with respect to the variation of fuel outlet location. Actually, 350psi was applied as static load and 12 gravity as a dynamic load during launching on the internal tank wall. The structural analysis was done with respect to attaching condition of the tank in the satellite. Also the effect of the variation of the propellant outlet location from $0^{\cire}$ to $25^{\cire}$ on the stress distribution was investigated. The equivalent stress distribution and optimal parameters induced from analysis results of the each condition will be used as the fundamental data to design the propellant tank.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.7
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• pp.981-986
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• 2009

The application of a cryogenic storage system is growing fast in different kinds of fields including to keep umbilical cord blood. Umbilical cord blood stem plays an important role in the treatment of a blood and immune system related genetic diseases, cancers and blood disorders. This study gives the optimal cryogenic system for cord blood banking. Three-dimensional models are employed and finite element method is used to do structure analyses of all designed models. The results shows model 3 have a good structure properties, and model 4 shows the best structure property as its maximum is 92.9 MPa. The other is too dangerous or infeasible to support load condition that allowed by STS 304. The results can be used in the design of these kinds of systems to obtain good predictions of trends over a wide range of design alternatives and operating conditions.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.280-283
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• 2015

Many construction projects have used the building information modeling (BIM) extensively considering data interoperability throughout the projects' lifecycles. However, the current approach, which is to collect the data required to support facility maintenance system (FMS) has a significant shortcoming in that there are various individual pieces of information to represent the performance of the facility and the condition of each of the elements of the facility. Since a heterogeneous external database could be used to manage a construction project, all of the conditions related to the building cannot be included in an integrated BIM-based building model for data exchange. In this paper, we proposed an ontology-based facility maintenance information model to integrate multiple, related pieces of information on the construction project using industry foundation classesbased (IFC-based) BIM data. The proposed process will enable the engineers who are responsible for facility management to use a BIM-based model directly in the FMS-based work process without having to do additional data input. The proposed process can help ensure that the management of FMS information is more accurate and reliable.

• Journal of Internet Computing and Services
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• v.21 no.1
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• pp.237-246
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• 2020

this paper, a data modeling method based on decision-making conditions is proposed for making combat and battlefield management systems to be intelligent, which are also a decision-making support system. A picture of a robot seeing and perceiving like humans and arriving a point it wanted can be understood and be felt in body. However, we can't find an example of implementing a decision-making which is the most important element in human cognitive action. Although the agent arrives at a designated office instead of human, it doesn't support a decision of whether raising the market price is appropriate or doing a counter-attack is smart. After we reviewed a current situation and problem in control & command of military, in order to collect a big data for making a machine staff's advice to be possible, we propose a data modeling prototype based on decision-making conditions as a method to change a current control & command system. In addition, a decision-making tree method is applied as an example of the decision making that the reformed control & command system equipped with the proposed data modeling will do. This paper can contribute in giving us an insight of how a future AI decision-making staff approaches to us.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6A
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• pp.955-963
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• 2006

As the geometrical characteristic of the curved bridge, the seismic response of curved bridges are different from straight bridges. This study analyzed the seismic response of the curved bridges considering diverse factors such as radius of curvature, direction of seismic load and support condition. The improved simple modeling of the curved bridge for seismic analysis is proposed, and it is compared with the detail modeling in order to verify the simple modeling. Three simply supported curved bridges and six 3-span continuous bridges are selected for seismic analysis. The behavior of curved bridges are evaluated in terms of the displacement and the force at supports and piers under seismic load applied in various directions. The results of this study show that upward reaction force may appear in simply supported curved bridge under seismic load. And continuous curved bridges are affected by the direction of the seismic load.