• Journal of Drive and Control
• /
• v.16 no.2
• /
• pp.8-14
• /
• 2019

A typical gantry crane is generally used to lift and transport objects in various workplaces. Most of the supporting structures in a gantry crane are fixed on the ground while the moving hoist is running overhead along the girder. There are some disadvantages to its long installation time and high installation cost. Therefore, a hydraulic based gantry crane was studied to solve the issues of typical gantry cranes. The supporting structure of the proposed gantry crane consisted of a hydraulic cylinder and telescopic boom. The dimension of the proposed gantry crane can be decreased due to its simplified structure. The analytical and theoretical methods were used to verify the structural stability of the proposed crane. The most severe load condition was considered for the analysis, and the stress and deflection of the structure are analyzed. The simulation results were as expected from the theoretical analysis. Finally, the structural and dynamic safety of the proposed hydraulic based gantry crane was validated. The obtained results can be used as guidelines in the design process of the hydraulic based gantry crane.

• The Journal of the Korea Contents Association
• /
• v.9 no.1
• /
• pp.30-44
• /
• 2009

In this paper, we propose the mobile P2P structure supporting content searches for mobile peers efficiently. The proposed mobile P2P structure is a 3-tier structure which consists of a mobile peer, a mobile super peer, and a stationary super peer to reduce the content search cost of mobile P2P service. For content searches, mobile peer searches content in the communication range and performs hierarchical content searches which is using mobile super peer, stationary super peer for expansion of query region. In order to support hierarchial content searches and the continuity of services according to peer mobilities, peer's join/leave processes are explicitly stored by supporting message structures to the upper layer It is shown through experimental evaluation that the proposed structure improves about 32% contents search performance over the existing 2-tier structure. Since it also reduces the messages transferred to the stationary super peers, it reduced about 25% search loads of them.

• Journal of KIISE:Computer Systems and Theory
• /
• v.29 no.4
• /
• pp.232-243
• /
• 2002

There are many methods for improving TLB (translation lookaside buffer) performance, such as increasing the number of entry in TLB, supporting large page or multiple page sizes. The best way is to support multiple page sizes, but any operating system doesn't support multiple page sizes in user mode. So, we propose the new structure of TLB supporting two pages to obtain the effect of multiple page sizes with high performance and at low cost without operating system support. we propose a new TLB structure supporting two page sizes dynamically and selectively for high performance and low cost design without any operating system support. For high performance, a promotion-TLB is designed by supporting two page sizes. Also in order to attain low power consumption, a banked-TLB is constructed by dividing one fully associative TLB space into two sub-fully associative TLBs. These two banked-TLB structures are integrated into a banked-promotion TLB as a low power and high performance TLB structure for embedded processors. According to the results of comparison and analysis, a similar performance can be achieved by using fewer TLB entries and also power consumption can be reduced by around 50% comparing with the fully associative TLB.

• The Journal of Korean Academy of Prosthodontics
• /
• v.35 no.1
• /
• pp.67-77
• /
• 1997

The purpose of this study was to evaluate a cases which was treated with konus telescope on the patients in bilaterally edentulous mandible. Author made konus telescope for two patients and then X-ray and clinical examination were used for evaluation of the function and change in supporting structure of the abutment teeth during the 60months. Patient complained of difficulties in removal of denture at the beginning but they got used to it soon. X-ray showed that there were no changes in supporting structure of the abutment teeth after 60 months. It was effective in promotion of ridge soreness and also reducing the need of relining. This study suggest that konus telescope was effective for the treatment of bilaterally edentulous situations.

• Journal of KIISE:Computing Practices and Letters
• /
• v.7 no.6
• /
• pp.715-723
• /
• 2001

This paper is a proposal of the world-wide messaging system for supporting wireless internet messaging against the existing system which has many limits on functionality and structure. To this work, this paper proposes the hierarchical structure to ensure an extensibility of an existing messaging system, and show the possibility via implementing and operating together wireless units.

• Journal of Industrial and Engineering Chemistry
• /
• v.67
• /
• pp.333-346
• /
• 2018

This study presents a mathematical modeling approach for developing models based on non-ideal conditions related to the membrane structure including porous supporting layer and deformation under pressure. Comparison of the findings with experimental data reveal the importance of considering the resistance in porous supporting layer though the effect of concentration polarization in the permeate stream could be neglected. Investigations on deformation of fibers under pressure ascertain that at larger fiber inner radius to outer radius ratios, increasing driving force may lead to an initial increase in permeability. After that, the effects of deformation dominates and thus permeability may be decreased.

• Journal of Digital Convergence
• /
• v.20 no.4
• /
• pp.247-260
• /
• 2022

In order to advance theoretical and practical understanding of innovative behaviors and affective commitment to change, this study investigated the relationship among innovation supporting organizational culture, decentralized structure, acceptance of organizational change, and affective commitment to change and tested the mediating effect of acceptance of organizational change in the relationship. Data were collected from 261 employees at H corporation and analyzed to test suggested research hypotheses using SPSS 20.0 and AMOS 20.0. The results are as follows: First, it is found that innovation supporting organizational culture influences positively acceptance of organizational change and affective commitment to change. Second, results show that decentralized structure influences positively acceptance of organizational change, but does not influence innovative behavior. Third, it is found that acceptance of organizational change influences positively affective commitment to change and innovative behavior. Fourth, it is also found that acceptance of organizational change mediates partially the relationship between innovation supporting organizational culture and affective commitment to change and acceptance of organizational change mediates completely the relationship between decentralized structure and affective commitment to change. With these findings, it is confirmed that innovation supporting organizational culture and decentralized structure influence positively affective commitment to change and innovative behavior through acceptance of organizational change. Limitations and suggestions were discussed.

• Journal of the Korean Society for Railway
• /
• v.1 no.1 s.1
• /
• pp.20-29
• /
• 1998

State of the art and current issues related with the RC and PSC structure system for the German magnetic levitation train "Transrapid" were investigated. The German magnetic levitation train adopted a new kind of a structure to enable high-speed transportation, which allows the use of the space over a ground. The loading from Transrapid is light-weight compared with a regular train due to load distribution to a supporting structure. Therefore, Transrapid is considered an economical and efficient transportation system, and is also an environmentally-sustainable structure. In this paper, the structural design and construction technology specific to a magnetic levitation train were discussed, and structural considerations related with an actual operation of the train were pointed out. In addition, the future research area of a magnetic levitation train was proposed.

• Journal of Korean Association for Spatial Structures
• /
• v.19 no.4
• /
• pp.27-34
• /
• 2019

Spatial structure does not have columns and walls installed inside, so they have a large space. There are upper structure and substructure supporting them. The response of seismic loads to the upper structure may be increased or decreased due to the effects of the substructure. Therefore, in this study, the seismic response of the upper structure and the floor response spectrum of the substructure were compared and analyzed according to the height of the substructure in the spatial structure where the LRB was installed. As a result, the possibility of amplification of response was confirmed as seismic waves passed though the substructure, which is likely to increase the response of the upper structures.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2007.05a
• /
• pp.859-865
• /
• 2007

This paper presents a method to analyze the unbalance response of a high speed polygon mirror scanner motor supported by sintered bearing and flexible supporting structures by using the finite element method and the mode superposition method. The appropriate finite element equations for polygon mirror are described by rotating annular sector element using Kirchhoff plate theory and von Karman non-linear strain, and its rigid body motion is also considered. The rotating components except for the polygon mirror are modeled by Timoshenko beam element including the gyroscopic effect. The flexible supporting structures are modeled by using a 4-node tetrahedron element and 4-node shell element with rotational degrees of freedom. Finite element equations of each component of the polygon mirror scanner motor and the flexible supporting structures are consistently derived by satisfying the geometric compatibility in the internal boundary between each component. The rigid link constraints are also imposed at the interface area between sleeve and sintered bearing to describe the physical motion at this interface. A global matrix equation obtained by assembling the finite element equations of each substructure is transformed to a state-space matrix-vector equation, and both damped natural frequencies and modal damping ratios are calculated by solving the associated eigenvalue problem by using the restarted Arnoldi iteration method. Unbalance responses in time and frequency domain are performed by superposing the eigenvalues and eigenvectors from the free vibration analysis. The validity of the proposed method is verified by comparing the simulated unbalance response with the experimental results. This research also shows that the flexibility of supporting structures plays an important role in determining the unbalance response of the polygon mirror scanner motor.