• The Journal of Korean Academy of Prosthodontics
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• v.44 no.2
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• pp.207-216
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• 2006

Statement of Problem: To conduct a successful function of implant prosthesis in oral cavity for a long time, it is important that not only structure materials must have the biocompatibility, but also the prosthesis must be designed for the stress, which is occurred in occlusion, to scatter adequately within the limitation of alveolar bone around implant and bio-capacity of load support. Now implant which is used in clinical part has a very various shapes, recently the fixture that has tapered form of internal connection is often selected. However the stress analysis of fixtures still requires more studies. Purpose: The purpose of this study is to stress analysis of the implant prosthesis according to the different implant systems using finite element method. Material and methods: This study we make the finite element models that three type implant fixture ; $Br{\aa}nemark$, Camlog, Frialit-2 were placed in the area of mandibular first premolar and prosthesis fabricated, which we compared with stress distribution using the finite element analysis under two loading condition. Conclusion: The conclusions were as follows: 1. In all implant system, oblique loading of maximum Von mises stress of implant, alveolar bone and crown is higher than vertical loading of those. 2. Regardless of loading conditions and the type of system. cortical bone which contacts with implant fixture top area has high stress, and cancellous bone has a little stress. 3. Under the vertical loading, maximum Von mises stress of $Br{\aa}nemark$ system with external connection type and tapered form is lower than Camlog and Frialit-2 system with internal connection type and tapered form, but under oblique loading Camlog and Frialit-2 system is lower than $Br{\aa}nemark$ system.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.1
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• pp.146-154
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• 2009

In recent tissue engineering field, it is being reported that the fabrication of 3D scaffolds having high porous and controlled internal/external architectures can give potential contributions in cell adhesion, proliferation and differentiation. To fabricate these scaffolds, various solid free-form fabrication technologies are being applied. The solid free-form fabrication technology has made it possible to fabricate solid free-form 3D microstructures in layer-by-layer manner. In this research, we developed a multi-head deposition system (MHDS) and used design of experiment (DOE) to fabricate 3D scaffold having an optimized internal/external shape, Through the organization of experimental approach using DOE, the fabrication process of scaffold, which is composed of blended poly-caprolactone (PCL), poly-lactic-co-glycolic acid (PLGA) and tricalcium phosphate (TCP), is established to get uniform line width, line height and porosity efficiently Moreover, the feasibility of application to the tissue engineering of MHDS is demonstrated by human bone marrow stromal cells (hBMSCs) proliferation test.

• Advances in Computational Design
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• v.2 no.3
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• pp.123-141
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• 2017

Solving a system of linear or non-linear equations is required to analyze any kind of structures. There are many ways to solve a system of equations, and they can be classified as implicit and explicit techniques. The explicit methods eliminate round-off errors and use less memory. The dynamic relaxation method (DR) is one of the powerful and simple explicit processes. The important point is that the DR does not require to store the global stiffness matrix, for which it just uses the residual loads vector. In this paper, a new approach to the DR method is expressed. In this approach, the damping, mass and time steps are similar to those of the traditional method of dynamic relaxation. The difference of this proposed method is focused on the method of calculating the damping. The proposed method is expressed such that the time step is constant, damping is equal to zero except in steps with maximum energy and the concentrated damping can be applied to minimize the energy of system in this step. In this condition, the calculation of damping in all steps is not required. Then the volume of computation is reduced. The DR method for form-finding of membrane structures is employed in this paper. The form-finding of the three plans related to the membrane structures with different loading is considered to investigate the efficiency of the proposed method. The numerical results show that the convergence rate based on the proposed method increases in all cases than other methods.

• Korean Journal of Construction Engineering and Management
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• v.13 no.1
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• pp.53-66
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• 2012

Gangform compared with conventional wood and steel form is systemized form which has a capability to install and dismantle form at a time without repeating to assembly and disassembly small members. Gangform compared with ACS has some problems such as 1) Tower Crane load increase, 2) increase in safety incidence during climbing Gangform, 3) decrease in detachment operation productivity, 4) stop work due to climate impacts, and 5) decrease in labor cost, productivity, quality. A conceptual design model of automated Gangform climbing system is suggested for apartment housing construction to show its technical/economic feasibility and workers' safety while increasing operation productivity and concrete quality.

• Journal of Ocean Engineering and Technology
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• v.15 no.4
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• pp.28-37
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• 2001

The water quality in Yongil Bay is getting worse due to the sewage and the waste water from the surrounding industrial complex. The study aims to simulate the current system that is necessary to build ecosystem model for the optium water quality control and clarify the correlation of current system characteristics with water quality in Yongil Bay. To clarify the characteristics of coastal water movement system and verify the applicability of the 3-D model, the current system was simulated using 3-D model baroclinic model which considers tidal current and density effects. As the results of numerical experiments, it is proved the 3-D model is the most applicable on appearing the current system of the stratificated Yongil Bay difference of density. Form the results of simulation considered tidal current only, it can be clarified that the water body flows in the inner bay through the bottom layer and flows out the outer bay through the surface layer in Yongil Bay. And the fresh water from the Hyongsan river and the thermal discharge form POSCO have a little effect on the current system in Yongil Bay, but the diffusion of heat and salt has an important effect upon the formation of the density stratification of the water quality distribution is closely related with the current structure characteristics as well as the tidal residual current system in Yongil Bay.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.4146-4151
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• 2012

In this paper, we have simulated the transient stability of power system with dynamic loads. Dynamic load characteristics have an important influence on power system stability. In study of power system stability, motors form a major portion of the system loads. Induction motors and synchronous motors in particular form the workhorse of the electric power industry. Therefore modelling of motors is important in system stability. We investigate the effect of motors loads of Kwang Yang network with three phase fault.

• Journal of Distribution Science
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• v.17 no.7
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• pp.87-98
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• 2019

Purpose - The goal of this research is to examine the influence of Quick Response on the supply chain performance. Furthermore, this study investigates the potential of Quick Response to be a more advanced form of supply chain collaboration program with extensive information sharing activities. Research design, data, and methodology - The mathematical model is developed to represent the two stage supply chain system with a single manufacturer and one retailer. In the numerical study with the proposed mathematical models, three supply chain systems including the traditional system, Quick Response, and the fully shared information system are compared in terms of their profits. Results - The numerical analysis shows both manufacturer and retailer obtain greater profits under Quick Response than in the traditional system. While the fully shared information outperforms Quick Response as well as the traditional system, it results in lower manufacturer's profit compared with Quick Response. Conclusions - According to the numerical examples, Quick Response is the effective supply chain collaboration program that is beneficial to every supply chain member. The fully shared information system, as a more advanced form of collaboration than Quick Response can bring more benefits to the whole supply chain system, but it is necessary to prepare the proper incentive program that enables every member to share its benefits equally.

• Journal of The Korean Digital Architecture Interior Association
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• v.10 no.3
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• pp.79-86
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• 2010

From the research which sees the building which uses a natural control method with ecological architecture, continuity tried to divide the building which uses a physical control method with sustainable architecture. Ecological architecture analyzes the microclimate of the area and applies mining and natural ventilation leads and that the interior environment controls, the condition of the site actively and there is a possibility of seeing. Also sustainable architecture which is possible to lead and recycling and reuse of the resources and energy cyclic process of the construction resources to lead and the interior environment to control. Therefore the case where the facility system and structural system become integrated design organically in natural circulating method is many. Specially the sunshade system and double skin system are combined and structural system of the building and there is a possibility of having the envelope which form is feature. Today the buildings lead and the system integration process where the integral parts are systematic is demanded the interior environment which and an external form and that, they make they are there is a possibility of seeing. the environmental building which hits joins in with natural control method and the structure and facility system are integrated and has the tendency which is developed and there is a possibility of saying that a meaning with the alternative construction will be able to reduce the resources and an energy.

• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.135-140
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• 1998

The concept of dissipativity and passivity are of interest to us from a theoretical as well as a practical point of view. It is well known that the Riccati equation is derived from the dissipation inequality which expresses the fact that the system is dissipative; the energy stored inside the system doesn't exceed the amount of supply which flows into the system. The pencil model is regarded as a representation based on behavioral approach introduced by J.C. Willems. It has first order in the internal variable and zeroth order in the external variable. In general, any matrix pencil is transformed into a canonical form which is consist of several kind of sub-pencils, One of them has row full rank for $^\forall S\;\in\;\mathds{C}\;\bigcup{\infty}$, we call it under-determined mode of the model. In our opinion, most important properties of dynamical system lay in the mode. According to the properties of canonical form for pencil, it is shown that the storage function which characterizes the dissipativity of the system can be written as a LMI for the under-determined mode, if the system doesn't include impulse mode.

• Journal of the Korea Computer Industry Society
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• v.7 no.3
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• pp.135-144
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• 2006

According th expansion of computer technology and fast spread of network today, change is accelerated to electronic filing document in information carrier that use existent paper. Accord ingly, it became very important issue that create electronic filing document, and manage information that is included to electronic filing document. XML is expected to act important role in electronic commerce, electronic library, construction of point application system of imagination college and so on furthermore as well as can be complicated in Internet and ease storage of structured document data, administration, search. It is not easy work that peon makes out this XML document. This dissertation is research about edit method to make out XML document as more easy and convenient. Introduced concept that input XML document using document form for this, and separated input process by process and process that make out actuality XML document using made XML document form that make XML document form. Such detached input method can improve efficiency of XML input because can input easily XML document if use XML document form that offer input person who do not know well about XML specialist or system.