• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.123-128
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• 2008

Generally the window of the building is an objective of mining and having a distant view and also for a circulation it will can open and shut because becomes the structure insulation, the meat detailed drawing it does a very difficult portion, it is. To reduce the loss of the energy which leads, to an air conditioning energy and an expense increase problem the color which the interior furniture and the clothing due to the augmentation and the corpse ultraviolet rays of the unpleasant feeling which is caused by with the transient one solar energy influx which leads the window will burn, it joins in the window and it confronts and the novel solution is demanded.

• Journal of Korea Foundry Society
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• v.30 no.4
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• pp.142-146
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• 2010

To elucidate the characteristics of cavitation erosion of super duplex stainless steel, a cavitation erosion test, an optical microstructure, a hardness test, and a transmission electron microscope (TEM) analysis were conducted. As aging time at $475^{\circ}C$ increased, the hardness of ferrite phase increased whereas that of austenite phase was nearly constant. The reason why the cavitation erosion resistance increased with an increase of aging time was due to the formation of W-rich phases (${\alpha}$') of a nanometer scale with the high hardness that were precipitated within ${\alpha}$-grains and at ${\alpha}$-grain boundaries during aging, compared with that of the solution annealed alloy.

• Journal of the Korea Institute of Building Construction
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• v.3 no.3
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• pp.73-81
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• 2003

In this paper, salt damage resistance of high durable concrete was tested. High durable concrete was made by using low water cement ratio, chemical admixture called super-durable admixture and mineral admixtures such as fly-ash, ground granulated blast-furnace slag, silica fume. Two kinds of salt damage resistance test were carried out. One method is chloride ion penetration test(ASTM C1202), and the other one is depth of chloride penetration test in saline solution. Test results were as followers: 1) The depth of chloride ion penetration increased exponentially as water cement ratio was increased and time passed. 2) Super-durable admixture had little effect on the improvement of salt damage resistance of concrete. 3) Silica fume and ground granulated blast-furnace slag were effective on salt damage resistance because of pozzolanic reaction, but fly-ash had a little effect.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.1
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• pp.1-10
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• 2015

In urban area, since multipath and signal attenuations frequently occur due to street trees, street lights and buildings, it is difficult to obtain accurate navigation solution using GPS. As these problems also impact negatively on the INS/GPS coupled system, implementing advanced transportation systems such as autonomous navigation system and Intelligent Transportation System (ITS) become quite hard. For this reason, to alleviate deterioration of navigation system performance in urban area, direction information extraction algorithm using vision system is proposed in this paper. 2D Finite Rate of Innovation (FRI) technique is applied to extract lane edges. The proposed technique is simulated using road images and feasibility of proposed technique is analyzed through the simulation results.

• Journal of the Korean Society for Heat Treatment
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• v.36 no.5
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• pp.261-269
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• 2023

This study aims to investigate the effects of tungsten additions on the microstructure, corrosion characteristics, and hardness of super duplex stainless steel heat-treated at two different annealing temperatures. Under the annealing temperature of 1100℃, the microstructure of the stainless steels consisted mainly of ferrite, while under the annealing temperature of 1000℃, significant amounts of austenite and secondary phases were also observed. In terms of corrosion characteristics in 3.5 wt%NaCl solution, there was not a significant difference due to W addition at the 1100℃ conditions. However, at the 1000℃, a tendency of decreased corrosion resistance was observed with increasing the tungsten content. On the other hand, the micro-hardness of the stainless steel heat-treated 1000℃ showed an increasing trend with tungsten addition. This increase can be mainly attributed to the higher fraction of secondary phases, primarily sigma, known for their high hardness.

• Journal of the Korean Electrochemical Society
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• v.2 no.2
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• pp.88-92
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• 1999

The apparent density. self-separation of the electrode composite from current collector in the electrolyte solution and specific resistance of electronic conduction of the electrode composite were examined by the variation of content of conductive material such as graphitic and black carbons in $LiCoO_2$ composite electrode for lithium ion battery. Increasing the content of conductive material, the apparent density of Lico02 composite electrode was decreased and that of $LiCoO_2$ in composite electrode was only rapidly decreased compared to that of composite. $LiCoO_2$ composite electrodes containing more than 4.1 weight percent of super s black as a conductive material were seU-separated by the immersion into 1 mol/I $LiPF_6$ in propylene carbonate and diethyl carbonate (1:1 volume ratio). Specific resistances related to the electronic conduction of composite electrode were decreased by the increasing the content i)f conductive material. Specific resistance of the composite electrode including $2\~3\%w/w$ of super s black as conductive material was similar to that of $12\%w/w$ of Lonza KS6. In the range of this study, super s black as conductive material is better than Lonza KS6 on battery capacity because of apparent density of $LiCoO_2$ in electrode composite including super s black is higher than that of Lonza KS6.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.3
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• pp.117-126
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• 1987

The author has analysed profile of flow in rear of motion with single ball with low Reynolds number performed interface layers. For each system whose viscosity of the lower phase is as large as or large that of the upper phase, the profile has based on the thickness of the ball in the lower phase is nearly independent of both the ball single and the physical properties of the upper phase of the solution. The examine of the characteristics between Darwin's total displacement of the fluid and data obtained in this study, the averaged volume of each cases was corrected by the viscosity in the lower phase. When the viscosity in the lower phase is less than that of the upper phase, the volume based on the displacement of the fluid in rear region of ball are influenced by both ball size and the viscosity ratio of the upper phase to the lower phase. In the range of the Reynolds number less than a constant values, the volume ratio is influenced by both Reynolds number and Moltion number but mainly Reynolds. In range of Reynolds number over than the value, the volume ratio is independent of Reynolds number, but influenced by Moltion number.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.35-39
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• 2015

Polyvinylchloride (PVC) thin films having a microporous structure could be prepared by using the solubility difference in solvents. PVC thin film with a water contact angle of $150^{\circ}$ or more was obtained from the PVC solution consisting of the mixture of tetrahydrofuran as a solvent and propanol as a non-solvent. In the drying process of dip-coated PVC film, the increase of drying temperature reduced the tendency of roughened surface, which led the decrease of surface hydrophobicity. As the addition of propanol in the solution with 1 wt% PVC increased, the uniformity of surface roughness was improved. In the case of oxygen plasma treatments, even though the surface structure of PVC thin film was not notably changed, the surface property of the film was changed from the super-hydrophobicity to hydrophilicity as a function of the plasma exposing time.

• Resources Recycling
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• v.24 no.5
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• pp.56-62
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• 2015

Solvent extraction experiments for the separation and recovery of Re from hydrochloric acid leaching solution of spent super alloy by Alamine 304-1 were carried out. The effects of some variables, such as the nature and concentration of the extractants, HCl concentration, and the presence of impurities were investigated. The synthetic solutions of Re were prepared by dissolving ammonium perrhenate (APR), Alamine304-1, Cyanex272 and $D_2EHPA$ were used solvent extractants distilled in kerosene. The extraction percentage of Re by Alamine304-1 was higher than the other extractants as Cyanex272 and $D_2EHPA$ and the percentage is about 99%. Only 99% of Re was extracted in the presence of Al, Co and V in HCl solution.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.6
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• pp.761-769
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• 1999

In this paper the effect of aging heat treatment to the Corrosion behavior for the Nimonic 80A superalloy was studied by AC Impedance methods. Tested solution was 3.5% with tempera-ture $25^{\circ}C$ Electro-chemical corrosion test were carried out for the Nimonic 80A super-alloy which solution heat treated at $1080^{\circ}C$ for 8 hours followed by aging heat treated at $650^{\circ}C,\;700^{\circ}C,\;750^{\circ}C\;800^{\circ}C$ and $850^{\circ}C$ with 16hours under vacuum environment. The obtained results were as follows; 1. Base metal and solution-treated materials were exhibited similar corrosion tendency as Ran-dle equivalent cell. The value of passive film resistance was 579 ohms for the base metal and 124,770 ohms for the solutionized metal such a difference was arose by the ${{\gamma}_^'}$ precipitate on the metal surface during heat treatment. 2. The measure value of $R_p$ for heat-treated at $650^{\circ}C,\;700^{\circ}C,\;800^{\circ}C$and $850^{\circ}C$ were 97,943, 93, 111, 26,961, 15,798 and 11,780ohm respectively. Which indicated that the passive film resistance Rp was reduced as aging temperature increased due to the growth of grain size and sensitization at the grain boundary. 3. The similar tendency was exhibited for corrosion behavior of the electro-chemical corrosion polarization method and AC impedance method and confirmed that AC impedance method was useful tool for corrosion research.