• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.52-59
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• 2016

For almost of concrete structures by placing in cold weather, it is very important that the selection of curing method at early aged construction stage. The Exothermic curing method with hot wire and rapid hardening cement is used mostly to prevent the initial cracks and the strength decrease. Most of the construction sites, however, have not been applied to the optimal curing method caused by the simple approaches and the empirical judgements. Therefore, this paper has proposed a evaluation algorithm of the exothermic curing method for representing heating temperature, period, position of hot wire by analyzing the transient heat transfer solution. This has been implemented, moreover, using an object oriented programming language to develop structural analysis system taking account risk parameters. This system is composed of input module, database module, database store module, analysis module, and result generation module. Linkage interface between the central database and each of the related module is implemented by the visual c# concept. Graphic user interface and the relational database table are supported for user's convenience.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.12
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• pp.975-986
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• 2013

This paper dealt with the fabrication and performance evaluation of the electronics housing made of lightweight composite materials, aiming at the enhancement of satellite mass savings by replacing conventional aluminum alloy widely used for satellite avionics with lightweight composite material. For this purpose, a fabrication process was designed to overcome low machinability of CFRP and to minimize the post-treatment. The composite housing with grid-stiffened and monolithic frame was made using co-curing method. Its performance was also evaluated regarding endurance, stiffness, thermal conductivity, electrical grounding, EMI protection and radiation shielding. The composite housing can provide the considerable mass savings over the aluminum housing with same dimension.

• Korean Journal of Microbiology
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• v.39 no.3
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• pp.197-200
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• 2003

In order to establish effective in situ PCR on the glass slide using the conventional DNA thermal cycler, several parameters should be considered. These include full accessibility of PCR reagents into the cells, prevention of diffusing PCR products out of the cells, loss of PCR reagents by nonspecific adherence onto the glass slide, dryness of PCR reagents by heat, and heat conductivity from the heat block to the glass slide. Especially, to guarantee the full accessibility of PCR reagents to sample, relatively higher concentration of PCR reagents (particularly 4.5 mM of $Mg^{++}$) was required while 5 to 10 units/50 ${\mu}l$ reaction of Taq enzyme was enough as long as the step of pre-PCR incubation was included. Dryness of sample was prevented by addition of distilled water into the empty slots in the heat block, thereby providing the reproducible temperature-time profile of PCR. Observed temperature was lower than the programmed temperature by 3 to $4^{\circ}C$.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.4
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• pp.57-63
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• 2008

The characteristics of the bio-oil produced by the pyrolysis process with pig feces was investigated in this paper. The continuous auger-type reactor produced bio-oil was maintained at the temperature range of 400 to $600^{\circ}C$, which was higher than a typical that in a conventional pyrolysis system. The pig feces was used as the feedstock. The bio-oil and its compositions were characterized by water analysis, heating values, elemental analysis, bio-oil compounds, by Gas Chromatography/Mass Spectrometry (GC/MS), and functional group by $^1H$ NMR spectroscopy. It was found that the maximum bio-oil yields of 21% w.t. was achieved at $550^{\circ}C$. This result suggested that this auger reactor might be a potential technology for livestock waste treatment to produce bio-oil because it is able to be improved to reach higher efficiency of bio-oil production in further study. The pyrolysis system reported herein had low heat transfer into the feedstock in the auger reactor so that it needs improve the heat conduction rate of the system in further study.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.1
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• pp.49-56
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• 2010

In the pyroprocessing of spent nuclear fuels, LiCl-KCl waste salt containing radioactive rare earth chlorides are generated. The radioactive rare earth oxides are recovered by co-oxidative precipitation of rare earth elements. The powder phase of rare eath oxide waste must be immobilized to produce a monolithic wasteform suitable for storage and ultimate disposal. The immobilization of these waste developed in this study involves a solid state sintering of the waste with host borosilicate glass and zinc titanate based ceramic matrix(ZIT). And the rare-earth monazite which synthesised by reaction of ammonium di-hydrogen phosphate with the rare earth oxides waste, were immobilzed with the borosilicate glass. It is shown that the developed ZIT ceramic wasteform is highly resistant the leaching process, high density and thermal conductivity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.1 no.1
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• pp.23-26
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• 2000

In spot welded joint. Electronic Speckle Pattern Interferometry(ESPI) method using the Model 95 Ar laser a video system and an image processor was applied to measure the stress Unlike traditional strain gauges or Moire method, ESPI method has no special surface preparation or attachments and can be measured in-plane displacement with non-contact and real time. In this experiment, specimens are loaded in parallel with a load cell. The specimens are made of the cold rolled steel sheet with 1mm thickness, are attached strain. gauges. This study Provides an example of how ESPI has been used to measure stress and strain inspecimen. The results measured by ESPI are compared with the data which was measured by strain gauge method under tensile testing.

• Resources Recycling
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• v.25 no.6
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• pp.92-97
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• 2016

Spray dried $Cr_2O_3$ powder having an agglomerated structure of particles was twice treated into a plasma flame to increase its apparent density. The powder subjected to the first densification treatment did not show the entirely melted state keeping inner particle hollows, and it was fully melted after the second processing only. The powder size as a result of the second treatment decreased, and the apparent density as well as flowability were increased due to melting and surface smoothing effects. But a part of particles after the second densified treatment showed the hollow structure, especially those which were above $30{\mu}m$ in size. This densification behavior of the powder has been qualitatively discussed in terms of the thermal conductivity and inner gas pressure within aggregates exposed to the plasma flame.

• The Research Journal of the Costume Culture
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• v.30 no.1
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• pp.88-101
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• 2022

Molybdenum is used in electrical contacts, industrial motors, and transportation materials due to its remarkable ability to resist heat and corrosion. It is also used to flame coat other metals. This study investigated, the thermal characteristics of the molybdenum sputtered material, such as electrical conductivity, and stealth effects on infrared thermal imaging cameras. To this end, molybdenum sputtered samples were prepared by varying the density of the base sample and the type of base materials used. Thereafter, the produced samples were evaluated for their surface state, electrical conductivity, electromagnetic field characteristics, thermal characteristics, stealth effect on infrared thermal imaging cameras, and moisture characteristics. As a result of infrared thermal imaging, the molybdenum layer was directed towards the outside air, and when the sample was a film, it demonstrated a greater stealth effect than the fabric. When the molybdenum layer was directed to the outside air, all of the molybdenum sputtering-treated samples exhibited a lower surface temperature than the "untreated sample." In addition, as a result of confirming electrical properties following the molybdenum sputtering treatment, it was determined that the film exhibited better electrical conductivity than the fabric. All samples that were subjected to molybdenum sputtering exhibited significantly reduced electromagnetic and IR transmission. As a result, the stealth effect on infrared thermal imaging cameras is considered to be a better way of interpreting heat transfer than infrared transmission. These results are expected to have future applications in high-performance smartwear, military uniforms, and medical wear.

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.765-771
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• 2003

The aim of this study was to standardize the various methods and recipes of Hwajeun (glutinous rice pancake with flower) appeared in the literature. For this purpose, the effects on the sensory and rheological characteristics of Hwajeun in terms of the various levels of oil and frying times were investigated. This experiment consisted of a sensory evaluation in terms of the acceptance (color, flavor, oily feeling, softness, chewiness, adhesiveness, taste and overall preference) and objective evaluation performed by a texture analyzer, a color difference meter and measurements of the water content and oil absorption. The moisture content of the treatments as a function of the frying time, S7, showed a significantly(p＜0.01) low value, and the oil absorption of the Hwajeun made with different frying times increased in proportion to the increment of the frying time(p＜0.001). In terms of color, the b value of the Hwajeun made with 16g oil for frying showed a higher value than the others. In the two bite compression test, the hardness of the Hwajeun made with 4g oil for frying showed a significantly (p＜0.001) high value among the S2 and S3 samples. As a result of the sensory evaluation for the Hwajeun made with various amounts of oil and frying times, the Hwajeun made with 16g oil for frying and a 2 min frying time for each side (S6) was the most preferred in terms of the softness, chewiness, taste and overall preference of the sensory evaluation

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.306-312
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• 1984

In the present study, in succession to the previous reports, the sterilizing values ($F_0$) of the thermal processes for the canned minced hen-clams in brine and the canned smoked baby-clams in oil were determined ana discussed. The heat penetration tests were carried out three times with three cans at a time for each canned product. The thermocouple was setted on the can so as the tip of the applicaotor fixed on the position a little below the geometrical center of the can. The test cans were placed in the middle layer of the crate in which the same canned products were loaded with, and test cans were arranged to the front, the middle and the rear in the retort. The heat penetration curve obtained for the canned minced hen-clams in brine showed a broken logarithmic heating curve, while that of the canned smoked baby-clams in oil showed a simple logarithmic heating curve. The calculated $F_0$ values for the canned minced hen-clams in brine were 47.79 for No. 2 can, 52.99 for Ne. 7 can. and 45.21 for No. 2 tuna can, respectively. And the $F_0$ value for th canned baby-clams in oil packed into No. 3B square can was 14.12. Additionally, the nomographs represent the relationship between $F_0$ vlaues and B values (process time including $42\%$ of come-up time) for the each canned product were constructed.