• Fashion & Textile Research Journal
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• v.19 no.1
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• pp.90-100
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• 2017

In this research, consumer awareness investigation and wearing test were carried out for obtaining useful data on the development of thermo-sensitive functional clothing material. A survey involved 216 people in Seoul and Kyeonggi-do, and 200 questionnaires data were analyzed by descriptive statistics and frequency using SPSS 17.0. Four healthy men in twenties were participated for wearing test. Subjects in normal loungewear were exposed to temperature change from the initial temperature $30^{\circ}C$ down to $5^{\circ}C$ for an hour in a climate chamber. The environmental temperature, surface temperature of garment and skin were measured. As a result, most of respondents have all season clothing products such as underwear, hosiery, and jogging suit for loungewear. Also, thermo regulator y functional clothes are frequently used as underwear and sweat shirt. The consumer awareness investigation on thermo regulatory functional clothing showed that the most important key buying factor is quick climate temperature response, easy maintenance, design and cost, in that order. Surface temperature of garment went down with the cooling down of environmental temperature. The lower environmental temperature, the greater temperature difference by body part showed. Skin temperature change by environmental temperature showed similar tendency of garment surface temperature. In comparison between garment surface and body skin, temperature difference became larger under the lower environmental temperature.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4C
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• pp.117-125
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• 2011

The practical use of the electrical resistivity, which can makes the acquirement of the high resolution data in specific area, is increased in order to obtain a reasonable data for a ground investigation. The objective of this study is development of TRPF(Temperature-compensated Resistivity Probe for Field test), and an application in the field test for obtaining a reliable electrical resistivity value about considering the temperature effects. Temperature sensor is attached at 15mm, 30mm, 90mm below from the cone tip in consideration with the results of temperature transient process of cone probe and safety, and the angle of cone tip is $60^{\circ}$ for geometrical reason and minimizing the disturbance during the penetration test. Diameter of the cone probe is equally 35.7mm and penetration rate is 2 cm/sec for a comparison with standard cones such as CPT and SPT, and others. The temperature change is instantly observed around $4^{\circ}C$ when touching the ground, and the comparing results among the other cones indicates that the temperature compensation should be conducted in the ground survey using the electrical resistivity. This study shows that the necessity of temperature effects compensation during penetration test through the development and field verification of TRPF (Temperature-compensated Resistivity Probe for Field test).

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3874-3897
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• 2023

A high-fidelity computational fluid dynamics (CFD) analysis was performed using the Large Eddy Simulation (LES) model for the lower plenum of the High-Temperature Test Facility (HTTF), a ¼ scale test facility of the modular high temperature gas-cooled reactor (MHTGR) managed by Oregon State University. In most next-generation nuclear reactors, thermal stress due to thermal striping is one of the risks to be curiously considered. This is also true for HTGRs, especially since the exhaust helium gas temperature is high. In order to evaluate these risks and performance, organizations in the United States led by the OECD NEA are conducting a thermal hydraulic code benchmark for HTGR, and the test facility used for this benchmark is HTTF. HTTF can perform experiments in both normal and accident situations and provide high-quality experimental data. However, it is difficult to provide sufficient data for benchmarking through experiments, and there is a problem with the reliability of CFD analysis results based on Reynolds-averaged Navier-Stokes to analyze thermal hydraulic behavior without verification. To solve this problem, high-fidelity 3-D CFD analysis was performed using the LES model for HTTF. It was also verified that the LES model can properly simulate this jet mixing phenomenon via a unit cell test that provides experimental information. As a result of CFD analysis, the lower the dependency of the sub-grid scale model, the closer to the actual analysis result. In the case of unit cell test CFD analysis and HTTF CFD analysis, the volume-averaged sub-grid scale model dependency was calculated to be 13.0% and 9.16%, respectively. As a result of HTTF analysis, quantitative data of the fluid inside the HTTF lower plenum was provided in this paper. As a result of qualitative analysis, the temperature was highest at the center of the lower plenum, while the temperature fluctuation was highest near the edge of the lower plenum wall. The power spectral density of temperature was analyzed via fast Fourier transform (FFT) for specific points on the center and side of the lower plenum. FFT results did not reveal specific frequency-dominant temperature fluctuations in the center part. It was confirmed that the temperature power spectral density (PSD) at the top increased from the center to the wake. The vortex was visualized using the well-known scalar Q-criterion, and as a result, the closer to the outlet duct, the greater the influence of the mainstream, so that the inflow jet vortex was dissipated and mixed at the top of the lower plenum. Additionally, FFT analysis was performed on the support structure near the corner of the lower plenum with large temperature fluctuations, and as a result, it was confirmed that the temperature fluctuation of the flow did not have a significant effect near the corner wall. In addition, the vortices generated from the lower plenum to the outlet duct were identified in this paper. It is considered that the quantitative and qualitative results presented in this paper will serve as reference data for the benchmark.

• Journal of Power System Engineering
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• v.12 no.5
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• pp.34-39
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• 2008

The combustion purpose of diesel engine is to reduce the emission of green gas and to produce high output. Generally, the regulation matter of emission gas is largely diveded by 'THC', 'NOx', 'CO' and 'PM'. Among those matters, the most problem is to disgorge into 'PM', the character of diesel combustion. Diesel PM can be controlled using Diesel Particulate Filter, which can effectively reduce the level of soot emissions to ambient background levels. $NO_2$ generated by the DOC is used to combust the carbon collected in the DPF at low temperature. To certificate DPF device that is suitable to domestic circumstances, it is necessary to exactly evaluate the DPF devices according to the regulation of DPF certificate test procedure fur retrofit. To do carry out the above-mentioned description the understanding of that regulation like the standard of PM reduction is needed. In this study the test procedure including test cycle and BPT test condition was examined, and also the test result for specific DPF was analyzed. In every test like field test, PM reduction efficiency test and Seoul-10 mode test, no defect was showed.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.199-205
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• 2000

The stud female threads for stud bolts tend to degrade faster by high temperature over 450 C. Therefore, inspection for replacement cycle of stud bolts is used to carry out many kinds of method such as ultrasonic test(UT), magnetic test(MT), wobble test, visual test and hardness test. The visual inspection among those has been only applied for stud female threads generally and wobble test is often used to apply stud bolts. In this paper, wobble test is applied for evaluation of stud female threads on the contrary stud bolts especially. It is also applied three types of inspection method included wobble test on the two sites which is used for each other different operation cycle and three kinds of acquisition data are compared with evaluation methods. From the results, we have studied the characteristic exchanging of integrity evaluation data distribution according to using time and proposed managing method for female thread of stud on the power plants.

• Journal of the Korean Geographical Society
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• v.46 no.1
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• pp.20-35
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• 2011

This study suggested the systematic steps for quality control, construction of the climatological reference series and homogeneity test and adjustment of temperature series in the Republic of Korea. It also attempted to evaluate more accurate magnitude of change using adjusted temperature data. All erroneous values produced by quality control were detected by internal inconsistency check. The method selected for homogeneity test in this study well defined fairly correct signals of station relocations. Therefore, this method might be regarded as the appropriate one to test homogeneity of temperature series of the Republic of Korea. The increase of temperature of the Republic of Korea after the adjustment were bigger than before the adjustment of annual and seasonal mean temperature. Adjusted temperature data produced by these steps will enable to evaluate more accurate characteristics and magnitude of climate change.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.48.1-48.1
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• 2011

In this presentation, We monitored weather data, such as global irradiance, ambient temperature, temperature of PV module, relative humidity and windspeed for 2 years, for determining accelerated test condition. then, we determined the temperature limit of accelerated test through weather data and FEM analysis. Detailed procedures will be summarized in this work. After analysing outdoor stress such as thermal stress, we decided main failure modes and mechanisms of PV module, especially solder joint of ribbon wire. we carried out the measurement of material properties such as thermal expansion coefficient for planning of accelerated test. we designed accelerated test based on FEM analysis results. we carried out thermal cycling test with 1 cell mini module for 3 months. We monitored the change of electrical performance every 1 week such as Voc, Isc, Pmax, etc. and then, we analized the ribbon wire/electrode intefaces. Detailed results will be summarized in this work.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.163-166
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• 2003

This paper presents the results of a series of performance tests for the Stilting cryocooler. Infrared sensor systems incorporating cryocoolers are required to be qualified to the appropriate environmental specification. Linear drive Stilting cryocooler have matured to the stage of undergoing formal qualification test program The thermal environmental test of the Stilting cryocooler is presented in this paper. We performed that low and high temperature keeping test from －4$0^{\circ}C$ to ＋6$0^{\circ}C$ and operating test at high and low temperature cyclic range with acceptance tests performed at scheduled intervals. Cooling capacity was determined as a function of cooler components temperatures at the compressor, hot end and cold tip. Tests performed on this cooler have been successful with a measured cooling performance of more than 0.8W＠80K for 23$^{\circ}C$ ambient temperature with 40 $W_{ac}$ input power.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.6
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• pp.561-569
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• 2000

Single phase and condensation heat transfer characteristics of ammonia in a horizontal tube have been investigated experimentally The horizontal test section is composed of smooth SUS316 tube for refrigerant flow, surrounding annulus for water flow, and temperature and Pressure measuring sensors. For single phase test, subcooled ammonia mass flux was varied from 320 to 501 kg/mrs and temperature was varied from 18 to $47^{\circ}C$. For condensation test, mass flux and saturation temperature were varied from 86 to 128 kg/$m^2$s and 34 to $47^{\circ}C$, respectively. The equations of Gnielinski Soliman et al., Traviss et at., Cavallini and Zecchin, Shah, Chen et al., Tandon et al., and Chilli and Anand were compared with the experimental data. New correlations are proposed based on the experimental results and the absolute mean deviation of the experimental data becomes 1.0% for single phase test and 4.9% for condensation test.

• Journal of the Korean institute of surface engineering
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• v.39 no.1
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• pp.18-24
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• 2006

Although stainless steels have the excellent corrosion resistance by passive film, they are susceptible to pitting corrosion in the environment containing halogen elements such as chloride ions. The resistance to pitting corrosion can be evaluated by measuring the critical pitting temperature (CPT). CPT values can be obtained using immersion, potentiodynamic and potentiostatic polarization test methods. Results on duplex 2205 stainless steels showed that CPT values were measured as $50^{\circ}C,\;55^{\circ}C\;and\;61^{\circ}C$, respectively for immersion, potentiodynamic and potentiostatic polarization test methods, depending upon the different test methods, even though the difference between CPT values are not much.