• Industrial Engineering and Management Systems
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• v.8 no.1
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• pp.66-71
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• 2009

This study proposes a new framework for designing disassembly methods. In recent years, environmental problems have become global issues. Recycling of used products or resources is recognized as a matter of significance since it may help reduce the risk of exhausting natural resources. Considering possible exhaustion of limited natural resources in the near future, reuse of products would gain more environmental significance. As yet, it relies hugely on manual disassembly, which labor cost places burden on the total recycling cost. The purpose of this study is to propose a methodology designing for manual disassembly works, and a creation method of a jig. By focusing on parts' connection and attachment relationship, parts are categorized in 5 categories (parent part, joint key part, attaching key part, child part, and independent part) according to the features that parts possess, and 3 kinds of connection relationships (parent part-joint key part connection, parent part-independent part connection and child part-child part connection) are clarified. Connection relationship and attachment relationship charts have also been created, and utilizing them, disassembly orders are settled, and a disassembly jig is devised. The proposed methodology is also applied to a real product and its work time is improved 42% form 31 to 13 seconds.

• Steel and Composite Structures
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• v.31 no.6
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• pp.617-628
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• 2019

As an extremely destructive accident, progressive collapse is defined as the spread of an initial local failure from element to element, resulting eventually in the collapse of an entire structure or disproportionately large of it. To prevent the occurrence of it and evaluate the ability of structure resisting progressive collapse, the nonlinear static procedure is usually adopted in the whole structure design process, which considered dynamic effect by utilizing Dynamic Increase Factor (DIF). In current researches, the determining of DIF is performed in full-rigid frame, however, the performance of beam-column connection in the majority of existing frame structures is not full-rigid. In this study, based on the component method proposed by EC3 guideline, the expression of extended endplate connection performance is further derived, and the connection performance is taken into consideration when evaluated the performance of structure resisting progressive collapse by applying the revised plastic P-M hinge. The DIF for structures with extended endplate beam-column connection have been determined and compared with the DIF permitted in current GSA guideline, the necessity of considering connection stiffness in determining the DIF have been proved.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.4
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• pp.29-36
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• 2009

This is a basic experimental study to apply FRP modular box member to a variety of construction structures exposed to flexural strength, such as a slab and a girder. Applying FRP modular box member to a real structure requires a large section. FRP box member was made into modular systems. Tests were conducted under various conditions in order to analyze jointing performance of the developed FRP modular box member as a large section. For the methods of jointing FRP modular box member, synthetic resins connection, mechanical connection, and a combination of both were used to test both length and breadth connection. As a result of the test, using urethane + two bolts + sheets was the most efficient method of connecting FRP modular box member. It is expected that the proposed joint system in this study will contribute to the increase of failure load and synthesis behavior of FRP modular box member.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.11
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• pp.2531-2542
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• 1997

This paper describes a method for region segmentation and string extractionin documents which are mixed with text, graphic and picture images by the use of the structural characteristic of connceted components. In segmentation of non-text regionas, with connection-characteristic functions which are made by structural characteristic of connected components, segmentation process is progressed. In the string extraction, first we organize basic-unit-region of which vertical and horizontal length are 1/4 of average length of connection components. Second, by merging the basic-unit-regions one other that have smaller values than a given connection intensity threshold. Third, by linking the word blocks with similar block anagles, initial strings are cresed. Finally the whold strings are generated by merging remaining word blocks whose angles are not decided, if their height and prosition are similar to the initial strings. This method can extract strings that are neither horizontal nor of various character sizes. Through computer exteriments with different style documents, we have shown that the feasibility of our method successes.

• Proceedings of the KSR Conference
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• 2000.11a
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• pp.295-302
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• 2000

Slab guideway, surface treatment, heat line installation, and joint connection for Automated Guideway Transit with rubber tire are researched. While the AGT with rubber tire is constructed in city, the precast slab guideway must be considered a reduction of the construction period and the noise under construction. which related with environment. To do that, a basic design and the structural analysis for the precast slab guideway with rubber tire are studied. The surface treatment and the heat line installation of that are also compared with currently used methods. Tining method is applied to the surface treatment adopted from the concrete pavement application currently in use. The connection method between the slab of bridge and precast guideway are suggested with a bolt type and a bond type. To minimize noise and vibration of the connection while the AGT is in driving, the slop connection method can be enhanced the serviceability.

• Journal of the Korean Society of Safety
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• v.30 no.2
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• pp.9-13
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• 2015

This paper describes the analysis of deterioration characteristics for connection factor used in grounding system. The connection method of grounding system is specified in IEC standard. In order to analyze the deterioration characteristics for connection factor, deterioration test was carried out when the connection factor was buried in salt water and underground. The test connection factors were C-type sleeve, clamp, and exothermic welding. As a consequence, most of the connection factor was corroded, and the electrical resistance decreased after deterioration. The analytical results can be used to establish the safety of grounding system.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.336-343
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• 2005

In the braced excavations, careful consideration must be given to the risks of progressive collapse of the entire support system due to failure of a single member. The existing connection methods of the excavation support system results in many problems during construction. To overcome these, simple joint method is proposed in this study. The full scale test and the numerical analysis using finite element method were performed to verify the safety of them. As results, simple joint method was good effective to increase strength. And it was good effective to decrease in numbers of bolt. Also, new method is cheaper than existing connection methods and a good construction as well.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.5
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• pp.455-463
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• 2010

This is a basic experimental study to apply FRP modular box member to a variety of construction structures exposed to flexural strength, such as a slab and a girder. Tests were conducted under various conditions in order to analyze jointing performance features of the developed FRP modular box member as a large section. For the methods of jointing FRP modular box member, chemical connection, mechanical connection, and a combination of both were used to test both vertical and horizontal jointing. As a result of the test, using urethane+two bolts+sheets was the most efficient method of connecting FRP modular box member, and confirmed the efficient behavior by a finite element analysis.

• Journal of Electrical Engineering and Technology
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• v.9 no.6
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• pp.2201-2208
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• 2014

In this research, the characteristics of Brush-less DC (BLDC) motor in accordance with winding connection method, both Y-connection and D -connection, has been identified with design methodology simply. BLDC motor has been designed for both winding connections, and their torque analysis has been performed considering ideal current source analysis and voltage source analysis with 6-step control. In addition, to reduce torque ripple of BLDC motor, caused by coil inductance, on voltage source analysis with 6-step control, we have proposed suitable control method which is Phase Advance Control. It is verified that the torque ripple has been decreased by virtue of phase advance control, advancing and widening conduction angle of switching, via performance analysis by Finite Element Analysis.

• Steel and Composite Structures
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• v.39 no.1
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• pp.109-123
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• 2021

This research endeavor intends to use the implicit finite element method to investigate the structural response of steel shear walls with partial plate-column connection. To this end, comprehensive verification studies are initially performed by comparing the numerical predictions with several reported experimental results in order to demonstrate the reliability and accuracy of the implicit analysis method. Comparison is made between the hysteresis curves, failure modes, and base shear capacities predicted numerically using ABAQUS software and obtained/observed experimentally. Following the validation of the finite element analysis approach, the effects of partial plate-column connection on the strength and stiffness performances of steel shear wall systems with different web-plate slenderness and aspect ratios under monotonic loading are investigated through a parametric study. While removal of the connection between the web-plate and columns can be beneficial by decreasing the overall system demand on the vertical boundary members, based on the results and findings of this study such detachment can lower the stiffness and strength capacities of steel shear walls by about 25%, on average.