• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.1
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• pp.122-128
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• 2016

The purpose of this study was to develop improved strength of an arm and a boom on over-load environment, which causes damage in the initial design statement. To develop improved strength of an excavator front group, we calculated load conditions using the MATLAB program, and using these conditions, we performed a structural analysis of an excavator front group for the maximum digging force condition. Finally we performed a topology optimization to reduce weights of an arm and a boom, and we re-modeled an arm and a boom based on the topology design results and re-performed the structural analysis. The strength of the re-design is higher than the initial design but its weight is almost the same as the initial design.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.2
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• pp.137-144
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• 2018

This study describes the 3D design and analysis of a composite insulation boom of an aerial work platform for electric work. Structural analysis of the composite insulation boom was performed using ANSYS and the total deformation, equivalent stress, and normal elasticity were investigated at 150 mm, 500 mm, 1,000 mm, and 1,500 mm using a mounted strain gauge. The results of the analysis and test were similar in a linearly increasing slope and the difference in the strain value was about 10%. This difference depends on the compressive force in the manufacturing process.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.464-465
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• 2008

This paper proposed a robust controller in order to handle the boom vibration of inspection robot. While a inspection robot moves on boom with vibration by weight occurs. Therefore, Boom as structure like cantilever beam appears vibration by weight of inspection robot. The Z axis of inspection robot operates with Sliding structure. inspection robot is used "Fuzzy Controller" for position control with Z axis. The developed robot system is composed of the specially designed car for inspection robot. The proposed Fuzzy Controllers are used to track position reference signal of Z axis. A Experiment verify that the proposed Fuzzy Controller design method can achieve favorable control performance with regard to external disturbance.

• Journal of Biosystems Engineering
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• v.31 no.4 s.117
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• pp.334-341
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• 2006

This study designed to develop a mower which can reach to side of a tractor or inclined road side and operate weeding. The prototype consists of 4 parts; the base and turning equipment, the boom, the arm, the weeder. The hydraulic actuators were divided into two operations, weeding and operation of boom and they were controlled by electrical equipment. Weeding was very effective when pressure set up at $15{\ell}/min$ using weeding, as $2.27kg{\cdot}m$, 2,210rpm. Weeding range of flail mower was 1.1 to 2.6m from the center of turning equipment at a flat. In case of disk mower, it was 1.5 to 2m. As a result of operation test, flail mower was appropriate for weeding at fence and short weeds, disk mower was appropriate for long weeds.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.2
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• pp.61-67
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• 2001

Development of a barrier system for floating debris at river is introduced. The system is to prevent pollution of coastal water caused by marine debris which originates from land. The system consists of harrier boom, mooring system and boom winder. The harrier boom, which is self-inflatable with circular band spring, guides floating debris to a collecting conveyer system. Design parameters of the harrier system were reviewed and its design criteria were established. Based on the established design criteria, a pilot harrier system was built and tested at Tanchon branch of the Han river. It is proved that the suggested system is very efficient to collect floating debris at river.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.61-63
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• 2004

The procurement of a mobile microwave scatterometer platform involved the consideration to ensure a mobile platform and equipment selected full-filled technical requirement and safety standard in Malaysia. Designing, and modification works involved engineering methodology in determining and selecting a suitable hydraulic telescopic boom that suit a selected mobile platform available locally. The mobile platform is a delivery system for microwave remote sensing microwave scatterometer and other accessories to any locations in Malaysia. Total loading to be carried by the mobile platform is 4500 kg and its overall weight must be 16,000 kg as recommended by hydraulic telescopic boom manufacturers. The telescopic boom will elevate microwave scatterometer system including the antenna to a maximum height of 27 m, and can also be rotated through $3600^{\circ}$. A mechanism is incorporated in the system to enable tracking or monitoring angular movement of the hydraulic telescopic boom when positioned towards predetermined target.

• Research in Community and Public Health Nursing
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• v.27 no.1
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• pp.21-30
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• 2016

Purpose: This research was conducted to identify long-term care service needs in the baby boom generation. Methods: Data were collected from September 3 to October 9, 2012 targeting 196 baby boomers residing in Seoul and Gyeonggi-do with the measurement of long-term care service needs having five domains. Collected data were analyzed using the SPSS 20.0 program. Results: Demand for long term care service in those who preferred nursing homes was highest as $4.40{\pm}0.69$ in the safe environment domain. In case of those preferring home care services, demand was highest as $4.37{\pm}0.56$ in the social interaction domain. People who preferred nursing homes had higher needs in personal health care and improvement of the service quality domains. Those who preferred home care services showed diverse needs according to their characteristics. Conclusion: The baby boom generation had high needs in all the domains of long-term care services and such needs were diverse according to their characteristics. However, long-term care services had limitations that they provided standardized and uniformed services only. Therefore, health care services and improved quality services should be provided in a way of meeting the users' needs, and tailored services should be provided in consideration of the users' characteristics.

• Computational Structural Engineering
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• v.6 no.1
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• pp.91-98
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• 1993

Minimum weight design of the boom of an excavator with stress and displacement constraints was performed. The procedure of analysis consists of the following steps. The finite element model of the boom was built up by using 227 triangular plate elements each of which has three nodes. And then the finite element program was implemented and its accuracy was verified by comparing its results with those of the commercial structural analysis package-ANSYS 4.4A. For the constraints of stresses and displacements, the design sensitivities of those were computed using direct differentiation method. To verify the reliability of them the results were compared with those of the finite difference method. The optimum design value was obtained by using PLBA(Pshenichny-Lim-Belegundu-Arora)non-linear optimization program which adopts the active set strategy. Using the above results, minimum weight design of an excavator boom showed an effect of 27% reduction in weight.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.1
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• pp.47-57
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• 2010

This study analyzes the dynamic response of a floating crane with a cargo considering an elastic boom to evaluate(or for evaluation of) its flexibility effect on their dynamic response. Flexible multibody system dynamics is applied in order to establish a dynamic equation of motion of the multibody system, which consists of flexible and rigid bodies. In addition, a floating reference frame and nodal coordinates are used to model the boom as a flexible body. The study also simulates the coupled surge, pitch, and heave motions of the floating crane carrying the cargo with three degrees of freedom by numerically solving the equation. Finally, the simulation results of the elastic and rigid booms are comparatively analyzed and the effects of the flexible boom are discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.377-378
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• 2006

The knuckle crane mainly consists of six parts such as swing, main boom, outer boom, extension boom, hydraulic rotor and knuckle. And the hydraulic rotor is connected at the end of extension boom has rotor block, rotor body, rotor vane. In this study, we carried out kinematics analysis of the hydraulic rotor block curvature for a knuckle crane. Then, we showed the formula to establish the radius of a circumscribed circle to form the rotor block curvature. Third, we analyzed the stress at each point of the rotor block curvature according to the contact angle. From the result of this study, we designed the rotor block curvature with a proper contact angle for a knuckle crane to guarantee the stability of hydraulic rotor.