• Journal of Convergence for Information Technology
• /
• v.10 no.3
• /
• pp.200-207
• /
• 2020

The purpose of this study was to investigate the effect of mechanical massage on abdominal region on the reduction of abdominal fat in obese middle aged women. 10 middle aged obese women were participated in as subjects and executed 20~30min's mechanical abdominal massage for 4 weeks. At the beginning and end of 4 week's treatment, measured body composition, waist circumference and abdominal fat area and analyzed using SPSS. As a result, there were significant decrease in body weight(p= .003), % bodyfat(p= .018), waist circumference(p= .029), VFA(p= .007), SFA(p= .045) and TFA(p= .007) according to 4 weeks' treatment. Considering these results, it can be suggested that mechanical massage treatment on abdominal region in middle aged obese women be a effective method to reduce abdominal fat and furthermore to prevent and cure cardiovascular disease and metabolic syndrome caused by obesity.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.2
• /
• pp.1216-1221
• /
• 2014

Poly(ethylene-co-isosorbide terephthalate) (PEIT) is interest in polymer which has isosorbide monomer that is renewable resources such as corn. However, there is important drawback which is low mechnical properties as increasing isosorbide contents. In this study, polycarbonate used to make up for drawback of mechanical properties of PEIT. In addition, PEIT used to improve the tensile elongation of polycarbonate because PEIT has good sheet proccessability. The effect of polycarbonate on morphology, thermal and mechanical properties were investigated using FE-SEM, DMA, TGA, UTM, and notched izod impact strength tester. As a result of this study, PEIT/PC blends were in compatible system and polycarbonate can act as an improvement of thermal stability and mechanical properties in the blends.

• Polymer(Korea)
• /
• v.29 no.5
• /
• pp.481-485
• /
• 2005

In this work, the thermal and mechanical properties of vapor grown carbon nanofibers (VGCNFs)-reinforced difunctional epoxy (EP) composites were investigated in the presence of the 0, 0.1, 0.5, 1.0, and $2wt\%$ VGCNFs. The thermal properties of the VGCNFs/EP composites were studied by thermo-mechanical analysis (TMA) and dynamic mechanical analysis (DMA). The mechanical properties of the VGCNFs/EP composites were also examined by universal testing machine (UTM), falling impact test, and the friction and wear tests. From experimental results, the thermal and mechanical properties of the VGCNFs/EP composites were improved with increasing the VGCNFs contents. This was due to the increase of crosslinking structure of the composites, resulting in improving the mechanical interlockings between VGCNFs and epoxy resins in the present composite system.

• Korean journal of food and cookery science
• /
• v.4 no.2
• /
• pp.51-56
• /
• 1988

The sensory and instrumental characteristics of warm and cool cooked rices with pressure and electric cookers were examined. The types of rice varieties tested were Choucheong (traditional rice variety) Samgang and Seogwang (high-yielding rice varietis) The result of sensor evaluation revealed more significant differences in most of appearance, texture characteristics than flavour. The difference of sensory characteristics according to the types of cookers and the warm or cool cooked rices was greatest in Seogwang among three varieties. The instrumental measurement of cooked rices using instron showed that the difference between types of varieties and cookers was more clearly in cool cooked rices than warm ones. Especially hardness in instrumental characteristics revealed highly signficant difference. With regard to the correlation between instrumental and sensory characteristics, hardness had a significantly high correlation with texture while others had low ones.

• The Journal of Korean Academy of Prosthodontics
• /
• v.59 no.2
• /
• pp.248-260
• /
• 2021

Cobalt-chromium alloys are used to fabricate various dental prostheses, and have advantages of low cost and excellent mechanical properties compared to other alloys. Recently, selective laser melting, which is an additive manufacturing method, has been used to overcome the disadvantages of the conventional fabrication method. A local rapid heating and cooling process of selective laser melting induces fine microstructures, grain refinement, and reduction of porosities of the alloys. Therefore, it can improve mechanical properties compared to the alloys fabricated by the conventional method. On the other hand, layering process and rapid heating and cooling cause accumulation of a large amount of residual stresses that can adversely affect the mechanical properties. A heat treatment for removing residual stresses through recovery and recrystallization process caused complicated changes in mechanical properties induced by phase transformation, precipitate and homogenization of the microstructures. The purpose of this review was to compare the manufacturing methods of Co-Cr alloys and to investigate the characteristics of Co-Cr alloys fabricated by selective laser melting.

• Journal of Adhesion and Interface
• /
• v.22 no.4
• /
• pp.128-135
• /
• 2021

In this study, the acid polyols containing acid groups were synthesized, the novel polyurethane adhesive was developed by introducing the acid polyol by content. The acid polyols were introduced, the mechanical properties showed the maximum value when the acid content was 0.1 to 0.3 wt%, and it was confirmed that the mechanical properties and adhesive strength decreased at the content higher than 0.5 wt%. As the acid group, carboxylic acid and sulfuric acid were introduced to compare properties, and carboxylic acid showed stronger hydrogen bonding potential than sulfuric acid and improved mechanical properties. In addition, the correlation between particle size and mechanical properties was confirmed by introducing ZnO and CaCO₃. When ZnO and CaCO₃ were introduced, an ionic bond was formed with an acid group, and it was confirmed that mechanical properties were increased.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.10a
• /
• pp.819-820
• /
• 2016

Electrical power distribution is consists of high voltage, low voltage and motor control center(MCC). Motor control centers involves turning the motor on and off, it is configured electronic over current relay to detect a motor overcurrent flows. Existing electronic over current relay detects electrical fault such as overcurrent, undercurrent, phase sequence, negative sequence current, current unbalance and earth fault. However, it is difficult to detect mechanical fault such as locked rotor, motor stator and rotor and bearing fault. In this paper, we propose a condition monitoring and fault diagnosis system for electrical and mechanical fault detection of rotating machinery. The proposed system is designed with signal input and control part, system interface part and data acquisition board for condition monitoring and fault diagnosis, it was possible to detect electrical fault and mechanical fault through measurement and control of insulation resistance, locked rotor, MC counter and bearing temperature.

• Composites Research
• /
• v.31 no.6
• /
• pp.398-403
• /
• 2018

Recently, environmental pollution caused by plastic waste, ecosystem disturbance of micro-plastics and human body accumulation are becoming big problems. In order to replace the traditional plastic, eco-friendly resin and natural fiber-based composite materials have been developed, but they have a disadvantage that their mechanical properties are significantly lower than those of synthetic fiber-based composites. In this study, eco - friendly nanofiber was extracted from seaweed and used as an additive in order to improve the mechanical properties of jute fiber-reinforced composites. Through the hand lay-up process, the composites were fabricated, and it was confirmed that the nanofiber was effective in improving the mechanical properties of natural fiber composites through tensile, bending and drop weight impact tests.

• Composites Research
• /
• v.35 no.2
• /
• pp.69-74
• /
• 2022

In this study, the conductive paste used in a wide range such as wiring in the electronic packaging field, the automobile industry, and electronic products is manufactured under various process conditions due to the simplicity of the process, and then the thermal, mechanical, and electrical characteristics are analyzed and simulation studies are conducted to optimize the process. to establish the conditions of the conductive paste manufacturing process. First, a conductive paste was prepared by setting various types of binder resin, an essential component of the conductive paste, and characteristics such as thermal conductivity, tensile strength, and elongation were analyzed. Among the binder resins, the conductive paste applied with a flexible epoxy material had the best physical properties, and a simulation study was conducted based on the physical property data base of the conductive face. As a result of the simulation, the best physical properties were exhibited when the Ag flake volume fraction was 60%.

• Journal of Aerospace System Engineering
• /
• v.17 no.1
• /
• pp.10-15
• /
• 2023

Wet multi-disk clutch, a power switching device of the ducted fan, was optimized and results were analyzed. The clutch was divided into two types depending on whether a mechanical lock-up was applied or not. It was optimized under each design condition. Transfer torque capacity, friction material surface pressure, friction surface temperature, and drag torque were calculated as factors to optimize the clutch. The volume of separator plate and drag torque were used as the objective function for optimization. In the case of Type 1, which did not include a mechanical lock-up, the clutch could be operated regardless of the pitch angle of the ducted fan. However, the outer diameter of the friction surface was doubled, the volume was increased by 5~7 times, and the drag torque was increased by 7~12 times compared to those of Type 2, which included a mechanical lock-up.