• Journal of Electrical Engineering and Technology
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• 제13권3호
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• pp.1392-1397
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• 2018

The potentiometric measurement result for a high resistance up to $100P{\Omega}$ using a low resistance, a low voltage source and a commercial digital multimeter(DMM) is presented. With the method, a resistance can be easily, fast and economically measured. Using the method, resistance ranges over the $10G{\Omega}$ range which is difficult to measure using a commercial DMM and resistance ranges between $100T{\Omega}$ and $100P{\Omega}$ which cannot measure using an insulation tester were measured within accuracy of a few percent. It is expected that it can be useful to determine the temperature and voltage effect of a high resistance and an insulation material because it uses a reference resistance with a low resistance, very low temperature and voltage effect. Besides, it is expected that it can be useful to calibrate a dc high voltage divider with a large resistance ratio and a very low resistance because arbitrary resistance ratio measurements are possible with it.

• 콘크리트학회논문집
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• 제12권2호
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• pp.43-51
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• 2000

This study is to investigate for the frost resistance of high-flowing concrete using finely ground granulated blast-furnace slag with experimental parameters, such as type of binder, type of superplasticizer and method of curing. The resistance to freezing and thawing of high-flowing concrete by type of binder and superplasticizer is presented differently. Though the frost resistance of high-flowing concrete is satisfactory under standard condition, it is required that high-flowing concrete has entrained air like plain concrete. Because the critical spacing factor, being capacity of frost resistance, of high-flowing concrete is longer that of plain concrete, the frost resistance of high-flowing concrete, using finely ground granulated furnace blast slag, is superior to that of plain concrete.

• 한국세라믹학회지
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• 제53권5호
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• pp.548-556
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• 2016

Recently, porous alumina-based ceramics have been extensively applied in the semi-conductor and display industries, because of their high mechanical strength, high chemical resistance, and high thermal resistance. However, the high electrical resistance of alumina-based ceramics has a negative effect in many applications due to the generation of static electricity. The low electrical resistance and high air permeability are key aspects in using porous alumina-based ceramics as vacuum chucks in the semi-conductor industry. In this study, we tailored the pore structure of porous alumina-based ceramics by adjusting the mixing ratio of the starting alumina, which has different particle sizes. And the electrical resistance was controlled by using chemical additives. The characteristics of the specimens were studied using scanning electron microscopy, mercury porosimetry, capillary flow porosimetry, a universal testing machine, X-ray diffraction, and a high-resistance meter.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권4호
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• pp.867-875
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• 2014

Planing crafts were specifically designed to achieve relatively high speeds on the water. When a planing craft is running at high speed, dynamic pressure on the bottom makes the boat rise on the surface of the water. This reduces the area of the sinking surface of the boat to increase air resistance. Air resistance means the resistance that occurs when the hull and deck house over the surface of the water come in contact with the air current. In this paper, we carried out a CFD numerical analysis to find optimal deck houses that decreased air-resistance on the water when planing crafts are running at high speed. We finally developed the deck house shape of high-speed planing crafts that optimally decreased air resistance.

• Corrosion Science and Technology
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• 제23권4호
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• pp.289-295
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• 2024

Zn-Mg-Al alloy hot-dip galvanized steel sheet has high corrosion resistance. Compared to conventional Zn coating with the same coating thickness, the high corrosion resistance Zn-Mg-Al coating is more corrosion-resistant. Various coating compositions are commercially produced and applied in diverse fields. However, these steel sheets typically contain up to 3 wt% magnesium. In recent years, there has been a growing demand for higher corrosion resistance in harsh corrosive environments. Therefore, variations in Mg and Al contents were investigated while evaluating primary properties and performance. As a result, we developed new alloy-coated steel with ultra-high corrosion resistance. A Zn-5 wt%Mg-Al coated steel sheet was evaluated for its corrosion resistance and various properties. As the amount of Mg added increased, the corrosion loss tended to decrease. The corrosion resistance of the coated steel sheet in a particular composition, the Zn-5 wt%Mg-Al coating sheet, was about 1.5 to 2 times higher than that of the conventional Zn-3 wt%Mg-Al coating sheet. Ultimately, this ultra-high corrosion-resistance coated steel sheet will provide a robust solution to conserve Zn resources and contribute to a low-carbon society.

• Corrosion Science and Technology
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• 제4권2호
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• pp.60-63
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• 2005

A high temperature resistant coating has been developed, which is mainly for heavy oil production pipes deserved the serious corrosion. The coating has excellent physical and mechanical performance and corrosion resistance at room and high temperature. In order to simulate the underground working condition of heavy oil pipes, the heat resistance of the high temperature resistant coating has been studied. The development and a study on the heat resistance of the DHT high temperature resistance coating have been introduced in this paper.

• 운동영양학회지
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• 제25권2호
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• pp.8-14
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• 2021

[Purpose] The purpose of this study was to investigate the effects of a high-fat high-sucrose (HFHS) diet on previously reported adaptations of cardiac morphological and contractile properties to resistance training. [Methods] Twelve-week-old rats participated in 12-weeks of resistance exercise training and consumed an HFHS diet. Echocardiography and skinned cardiac muscle fiber bundle testing were performed to determine the structural and mechanical adaptations. [Results] Compared to chow-fed sedentary animals, both HFHS- and chow-fed resistance-trained animals had thicker left ventricular walls. Isolated trabecular fiber bundles from chow-fed resistance-trained animals had greater force output, shortening velocities, and calcium sensitivities than those of chow-fed sedentary controls. However, trabeculae from the HFHS resistance-trained animals had greater force output but no change in unloaded shortening velocity or calcium sensitivity than those of the chow-fed sedentary group animals. [Conclusion] Resistance exercise training led to positive structural and mechanical adaptations of the heart, which were partly offset by the HFHS diet.

• 국제초고층학회논문집
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• 제7권4호
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• pp.287-298
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• 2018

High strength steels have been widely applied in recent years due to high strength and good working performance. When subjected to fire conditions, the strength and elastic modulus of high strength steels deteriorate significantly and hence the load bearing capacity of structures reduces at elevated temperatures. The reduction factors of mechanical properties of high strength steels are quite different from mild steels. Therefore, the fire design methods deduced from mild steel structures are not applicable to high strength steel structures. In recent ten years, the first author of this paper has carried out a lot of fundamental research on fire behavior of high strength steels and structures. Summary of these research is presented in this paper, including mechanical properties of high strength steels at elevated temperature and after fire exposure, creep response of high strength steels at elevated temperature, residual stresses of welded high strength steel member after fire exposure, fire resistance of high strength steel columns, fire resistance of high strength steel beams, local buckling of high strength steel members, and residual strength of high strength steel columns after fire exposure. The results show that the mechanical properties of high strength steel in fire condition and the corresponding fire resistance of high strength steel structures are different from those of mild steel and structures, and the fire design methods recommended in current design codes are not applicable to high strength steel structures.

• 운동영양학회지
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• 제14권2호
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• pp.75-80
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• 2010

We evaluated the effect of the ginsenoside Re on insulin resistance of glucose transport in muscles of rats made insulin resistant with a high fat diet. After a week of adaptation period to the laboratory environment, 40 male wistar rats were randomly assigned into 2 groups (Chow diet group; CD, n = 20, High fat diet group; HFD, n = 20). After 5-week of high fat diet, Food was removed after 6:00 PM the day before the experiment. The following morning, rats were anesthetized by an intraperitoneal injection of pentobarbital sodium (50 mg/kg body wt), and the soleus muscles were removed. Before incubation, the soleus muscle was split longitudinally into strips with an average weight of 15~20 mg. After the muscle dissection was completed, the abdominal cavity was opened, and the epididymal, mesenteric, and retroperitoneal fat pads were removed and weighed. Treatment of muscles with ginsenoside Re alone had no effect on glucose transport. The high fat diet resulted in ~50% decreases glucose transport rate in soleus muscles. Treatment of muscles with ginsenoside Re in vitro for 90 min completely reversed the high fat diet-induced insulin resistance of glucose transport in soleus muscles. This effect of ginsenoside Re is specific for insulin stimulated glucose transport, as Re treatment did not reverse the high fat diet-induced resistance of skeletal muscle glucose transport to stimulation by contraction. Our results show that the ginsenoside Re induces a remarkably rapid reversal of high fat diet-induced insulin resistance of muscle glucose transport.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 추계 학술논문 발표대회
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• pp.33-38
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• 2005

It is applied in the high quality equipment construction by introduction of this high duality treating technology (ozone treating, activated carbon treating, high quality oxidation treating, UV treating etc.)waterproofing or corrosion proof method caused secondary economy damage of operation discontinuance and high quality treating equipment for applying existent waterproofing method that corrosion proof ability (ozone resistance performance, chemical resistance etc.) and abrasion resistance performance by comprehension insufficiency of user and designer. Therefor, In this study, we will analyze problem of waterproofing and corrosion material of existing construction application by high quality treating, and measure physical performance change by various condition. It is required to waterproofing and corrosion system and application of the field valuation.