• Journal of Ocean Engineering and Technology
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• v.23 no.3
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• pp.14-19
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• 2009

The present study developed a model to estimate the light weight of an ultra-large container ship. The weight estimation model utilized container ship data obtained from shipyards and the subdivided this weight data into appropriate weight groups. Parameters potentially affecting the group weight were selected and expanded based on experience for weight estimation, and a correlation analysis was performed by the SPSS program to determine the key parameters characterizing the group weight. A weight estimation model applying the multi-regression analysis was proposed to assess the weight of an ultra-large container ship at the preliminary design stage, and the results obtained by the suggested method showed good agreement with the shipyard data.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.4
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• pp.44-51
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• 2017

An ultra light quad-rotor is utilized in various areas for military and commercial purpose. Especially, the airframe shape is designed with various airframe size, weight and purpose. In this paper, the initial airframe shape of the quad-rotor was designed and manufactured. Flight test was conducted for the quad-rotor. The design modification of airframe shape was conducted to meet design requirement. By changing design, weight of airframe structure was reduced and payloads were placed to the best position. By reinforcing ribs and reducing vehicle's legs, the durability of airframe structure was enhanced.

• Textile Coloration and Finishing
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• v.25 no.4
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• pp.279-286
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• 2013

Application properties of ultra light weight silica aerogel toward polyurethane membranes were investigated. From the results of pre-milling process of the silica aerogel, the solvent for dispersion of the aerogel was determined for methyl ethyl ketone and its content in the solvent was determined by 30%. Using this aerogel dispersion, the polyurethane membranes were prepared according to the mixing amount of silica aerogel and various properties of the membranes were investigated. As results, the optimum mixing amount of silica aerogel inside polyurethane membranes was decided at 11%, because the improvement of light weight property, air permeability, and moisture vapor permeability were improved upto 11% of silica aerogel content, maintaining the water penetration resistance almost unchanged.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.3
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• pp.485-492
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• 2008

Computers used fer light-weight computing environments are considerably limited in resources and performance running in ubiquitous environment. Because of the limited resources, it is difficult to apply existing security technologies to the light-weight computers. In this paper, light-weight security software is implemented using RC-5 encryption and SHA-1 authentication algorithm which is appropriate for light-weight computing environments. The design of components based on security software of a light-weight computer application and the test-bed for security software are presented. The simulation verifies the correctness of the security software. The architecture of the light-weight and reconfigurable security software for light-weight computer applications is proposed. The proposed security software is small size and provides reconfigurable security library based on the light-weight component and the software manager that configures software platform is loaded with the library at the time it is needed.

• Design & Manufacturing
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• v.12 no.2
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• pp.34-39
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• 2018

The biggest topics in the automobile industry are light weightening and fuel efficiency improvement. There's a lot of research going on. It is focused on light weight materials. Light weight material is seen as the best way to reduce fuel consumption and to solve the problem of environmental pollution and resource depletion. For the light weight materials, new materials such as aluminum, magnesium, and carbon-hardening materials can be found. Research on the joining techniques of dual materials, improvement of material properties by improving the method of manufacture of existing materials, and studies on ultra-high strength steel sheets are expected to take up the most weight in lightweight materials. As the strength of the ultra-high strength steel sheets increases during forming, it is difficult to obtain dimensional precision due to the increase in elastic restoring force compared to mild or high strength steel sheets. Spring back is known to be affected by a number of factors due to poor plastic molding, and can be divided into the effects of the material spraying and the process. The study on the plasticitic variables were studied as plasticitic factors that can be controlled by a part company. Tensile testing of ultra-high strength materials was conducted to derive properties for plasticitic analysis and to analyze spring back with two factors controlling the height of the bead and blank holding force by adding tensile force and controlling the flow rate.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.21 no.1
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• pp.62-67
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• 2013

Human Powered Aircraft (HPA) should be light in weight and have high efficiency because power source of propulsion is human muscles. Airframe structure takes up most of empty weight of aircraft, so weight reduction of structure is very important issue for HPA. In this paper, design/analysis/test procedures for ultra light weight structure of the HPA developed by Korea Aerospace Research Institute (KARI) are explained briefly. Structural design is conducted through case studies on HPA in the USA and Japan. Loads analysis is performed to calculate design loads which is needed for structural design and analysis. Structural analysis is conducted for structure sizing. Static strength test of main wing spar which is primary structure of wing is performed to verify structural integrity.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.6
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• pp.130-135
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• 2018

Currently the automobile market is developing eco-friendly vehicles in order to cope with fuel efficiency regulations. Many studies have been conducted to improve travel performance and fuel economy of the environment-friendly vehicles, and vehicle manufacturers study how to manufacture light-weight vehicles for improving fuel economy for both existing vehicles and environment-friendly vehicles. Exemplary light-weight vehicle technologies include optimal design of vehicle body structure which is a light-weight vehicle method by changing component shapes or layout to optimize the vehicle body structure and the new process technology for using new light-weight and very strong materials Various studies.

• Journal of the Korean Society of Safety
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• v.26 no.2
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• pp.1-5
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• 2011

In order to evaluate fatigue endurance for an ultra-light weight inline skate frame, FEM analysis was performed. Tensile properties and a S-N curve were determined through tensile and fatigue tests on a modified Al-7075+$S_c$ alloy. The yield and ultimate tensile strengths were 553.3 MPa and 705.5 MPa, respectively. The fatigue endurance limit of this alloy was 201.2 MPa. For evaluating the fatigue endurance of the inline skate frame, the S-N data were compared with the stress analysis results through FEM analysis of the frame. The maximum Von-Mises stress of the frame was determined 106 MPa through FEM analysis of the frame, assuming that the rider weight is 75 Kg. Conclusively, on the basis of fatigue limit, the inline skate frame has a safety factor of approximately 2.0.

• Bulletin of the Korean Chemical Society
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• v.27 no.3
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• pp.413-418
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• 2006

Sodium hyaluronate (NaHA), water soluble polymer having ultra-high molecular weight, is characterized by using on-line frit inlet asymmetrical flow field-flow fractionation (FI-AFlFFF) and multiangle light scattering (MALS). This study demonstrates the capability of power programming FI-AFlFFF for the separation of NaHA and the applicability of FI-AFlFFF with MALS for the characterization of molecular weight distribution and their structural information. Since sample injection and relaxation in FI-AFlFFF are achieved by using hydrodynamic relaxation, separation of high molecular weight polymers can be achieved smoothly without halting the separation flow. Experiments are carried out with the two different NaHA products (a raw NaHA sample and a thermally degraded NaHA product) and molecular weight distribution and conformations in solution are determined. Influence of sample filtration on the change of molecular weight distribution is also discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.67-68
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• 2006

In this paper, a new revolute cooperating robot arms with 12 d.o.f was developed for autonomous moving robots. The robot ann was designed to have the load capacity of 10 Kg. For this, a new joint actuator based on the fourbar link mechanism was employed. As a control system for the robot arm, a distributed control system was developed composed of the main controller and five motor controller for the ann joints. The main controller and the motor controller were developed using the ARM microprocessor and the TMS320c2407 processor, respectively. To validate the performance of the robot system, an experiment to support 10 Kg payload was performed.