• International journal of advanced smart convergence
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• v.6 no.2
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• pp.1-8
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• 2017

Recently, the development of the information communication industry has made many changes in the industrial acoustic industry. Especially, it has a great influence on the change of system and equipment of acoustic system. Analog equipment is changing to digital equipment, and integrated control equipment makes it easier to operate and manage the sound system. However, the integrated control system currently on the market is only controllable for some devices. In this paper, we propose a new AoIP - based system configuration method, which enables the operation status monitoring, unmanned operation and self - diagnosis of equipment. As a result of the study, it is confirmed that the proposed system can be operated, monitored, and self - diagnosed at remote sites. It is expected that an AoIP- based sound system will be the industry standard in the future.

• Korean Journal of Construction Engineering and Management
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• v.1 no.4 s.4
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• pp.98-105
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• 2000

The drawing information takes the most essential part of construction information. The management of construction information through drawing information facilitates input, output and search process, thus helping maximize the usage of construction information by effectively sharing construction experience and drawing information. This paper shows how construction information can effectively used to increase the productivity of the construction process as a whole. Construction information was extracted and classified by the elements of building which are the basic and very end components of building, to accumulate information of each construction phase. Based on the result, the Element Breakdown Structure(EBS) was developed for the practical usage of construction information integration.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.11
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• pp.2245-2252
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• 2002

Design sensitivity analysis scheme is proposed in an elasto -plastic finite element method with explicit time integration using a direct differentiation method. The direct differentiation is concerned with large deformation, the elasto-plastic constitutive relation, shell elements with reduced integration and the contact scheme. The design sensitivities with respect to the process parameter are calculated with the direct analytical differentiation of the governing equation. The sensitivity results obtained from the present theory are compared with that obtained by the finite difference method in a class of sheet metal forming problems such as hemi-spherical stretching and cylindrical cup deep-drawing. The result shows good agreement with the finite difference method and demonstrates that the preposed sensitivity calculation scheme is a pplicable in the complicated sheet metal forming analysis and design.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.195-199
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• 1993

In the analysis of metal forming processes by the finite element method, there are many numerical instabilities such as element locking, hourglass mode, shear locking. These instabilities may have a bad effect upon accuracy and convergence. The present work is concerned with improvement of stability and efficiency in two dimensional rigid-plastic finite element method using various type of elements and numerical integration schemes. AS metal forming examples, upsetting and backward extrusion are taken for comparison among the methods : various element types and numerical integration schemes. comparison is made in terms of stability and efficiency. As a result, it has been shown that the finite element computation is stabilized from the viewpoint of computational time, convergency, and numerical instability.

• International Journal of Aeronautical and Space Sciences
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• v.11 no.3
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• pp.240-245
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• 2010

The controller of a model reference adaptive control monitors the plant's inputs and outputs to acknowledge its characteristics. It then adapts itself to the characteristics it encounters instead of behaving in a fixed manner. An important part of every adaptive scheme is the adaptive law for estimating the unknown parameters on line. A more precise model is required to improve performance and to stabilize a given dynamic system, such as a satellite in which performance varies over time and the coefficients change due to disturbances, etc. After model identification, the robust controller ($H{\infty}$) is designed to stabilize the rigid body and flexible body of a satellite, which can be perturbed due to disturbance. The result obtained by the $H{\infty}$ controller is compared with that of the proportional and integration controller which is commonly used for stabilizing a satellite.

• Computational Structural Engineering
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• v.9 no.4
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• pp.107-115
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• 1996

Displacement response is one of the important parameter to determine vibration characteristics of bridge structure. Reliable estimate of displacement response is obtained economically from integration of measured acceleration data in frequency domain. Proper sampling rate of frequency in discretization process of measured acceleration is proposed. Comparison of integrated and directly measured displacement response from laboratory experiment for a cantilever beam shows good agreement each other. Mode shape obtained from estimated displacement response also closely match with analytical result, thus the developed method is proved to be effective in practical use.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.6
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• pp.831-837
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• 2013

MEMS accelerometer provides a low cost alternative in retrieving the acceleration signal for motion sensing. Theoretically, displacement can be calculated by double integrate the acceleration signal. However, in practical, it could not be done in straight forward manner due to several factors that exist in the real world. This experiment focuses on the processes from practical accelerometer signal acquisition till the result of double integration for low frequency vertical motion.

• Journal of the Korean Society of Safety
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• v.21 no.3 s.75
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• pp.87-93
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• 2006

When a structure is constructed at the site composed of soil, the behavior of a structure is much affected by the characteristics of soil. Therefore, the effect of soil-structure interaction is an important consideration in the design of a structure at the site composed of soil. Precise analysis of soil-structure interaction requires a proper description of soil profile. However, most of approaches are nearly unpractical for soil exhibiting material discontinuity and complex geometry since those cannot consider precisely complicated soil profiles. To overcome these difficulties, an improved integration method is adopted and enables to integrate easily over an element with material discontinuity. As a result the mesh can be generated rapidly and highly structured, leading to regular and precise stiffness matrix. The influence of soil profile on the response is examined by the presented method. It is seen that the presented method can be easily used on soil-structure interaction problems with complicated soil profile and produce reliable results regardless of material discontinuities.

• Coupled systems mechanics
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• v.5 no.1
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• pp.59-86
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• 2016

This paper deals with the free vibration analysis of a dynamical coupled system: flexible gravity dam- compressible rectangular reservoir. The finite element method is used to compute the natural frequencies and modal shapes of the system. Firstly, the reservoir and subsequently the dam is modeled by classical 8-node elements and the natural frequencies plus modal shapes are calculated. Afterwards, a new 21-node element is introduced and the same procedure is conducted in which an efficient method is employed to carry out the integration operations. Finally, the coupled dam-reservoir system is modeled by solely one 21-node element and the free vibration of dam-reservoir interaction system is investigated. As an important result, it is clearly concluded that the one high-order element treats more precisely than the eight-node elements, since the first one utilizes fifth-degree polynomials to construct the shape functions and the second implements polynomials of degree two.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.256-263
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• 1993

The integration of deburring robots into product quality and productivity impact the industrial. In this paper the intelligent system of robotic deburring is proposed integrated with robot system, image processing system, force sensor system and host PC. The size, position, recognition of burr is determined by the information that the image processing system processed. The feed velocity of cutting tool is controlled by the information that the force sensor system processed. The integration of these information can remove the uncertainty of the information of deburring on the cutting path. The result of these technologies is useful for the development of the factory automation and automatic inspection equipments.