• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.354.1-354.1
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• 2016

Nanoporous gold (NPG) is a very promising material in various fields such as sensor, actuator, and catalysis because of its high surface to volume ratio and conducting nature. In this study, we fabricated a NPG based amperometric sensor on a glass substrate by means of co-sputtering of Au and Si. During the sputtering process, we found the optimum conditions for heat treatment to reduce the residual stress and to improve adhesion between NPG films and the glass substrate. Subsequently, Si was selectively etched from Au-Si alloy by KOH solution, which forms nanoporous structures. Scanning electron microscopy (SEM) and auger electron spectroscopy (AES) were used to estimate the structure of NPG films and their composition. By employing appropriate heat treatments, we could make very stable NPG films. We tested the performance of NPG sensor with aniline molecules, which shows high sensitivity for sensing low concentration of aniline.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.4
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• pp.291-300
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• 2015

In the steel manufacturing process heat-endurance deterioration of a ladle used to cause a big accident. In this paper, an infrared imaging system and image analyzing procedure are proposed for inspecting refractory bricks of a ladle. The proposed algorithm contains following three parts: two-stage image selection procedure, reference point detection, and analysis of heat-endurance deterioration. Experiments were conducted with real data from a steel plant and detailed configuration of infrared imaging system was presented.

• Fire Science and Engineering
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• v.9 no.1
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• pp.20-29
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• 1995

The sprinkler head is a component of the sprinkler system intended to discharge water for automatic detection and extinguishment of fires. On this study, thermal characteristic values affecting the sensitivity of the fusible alloy type sprinkler head were obtained and analyzed under heated air stream condition which had constant temperature and velocity. The experiment was carried out under the forced convection condition with both the conductive heat loss considered and neglected. The thermal characteristic values of the sprinkler head were obtained in accordance with the material and shape of the heat responsive element and the conditions of the main body.

• Korean Journal of Materials Research
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• v.13 no.9
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• pp.561-566
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• 2003

Mechanical alloying(MA) process using elemental powders followed by hot pressing has been applied to some intermetallic alloy system containing ferromagnetic elements, such as NiAl and $FeSi_2$. A modified thermogravimetric analysis (TGA) technique was used to investigate the degree of alloying in milled powders and hot consolidated specimens as well as heat-treated bulk specimens. It is shown that the measurement of Curie temperatures in MA intermetallic powders and consolidated specimens containing ferromagnetic components, when determined as a function of milling and heat treatment parameters, can give some insight into the progress and mechanism of alloying.

• Fire Protection Technology
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• s.29
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• pp.39-45
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• 2000

All objects emit thermal radiation and this radiation is the basis of the techniques used to detect flames. The usual phenomena occurring in the initial stage of a fire are generally invisible products of a combustion and visible smoke. Liquid or gaseous materials do not undergo a smoldering stage such fires develop very rapidly. Also, the heat generated by the initial flames is usually not sufficient to active a heat detector. In this case the most effective criterion for automatic fire detection is the flame. In fire regulation of korea, the compulsory standard provided that a flame detector shall be installed a place of the attachment hight of detector is higher than 20 m, chemical plants, hangar, refinery, etc.. The result of the research and development are discriminated between a flame and other radiant emitters, developed PZT pyroelectric element is based on the use of photo-voltanic cell, developed IR band-pass filter that only allow a 4.3 radiation wavelength to reach the sensors and developed IR flame detector.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.4
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• pp.258-262
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• 2017

Recently energy consumption has been increasing because of advances in the industry, and electrical fires have accounted for 31.9% of all fire accidents. An electrical fire is caused by a short circuit, power surge, or poor contact. Safety devices for short circuits or power surges are currently mandatory and can actually detect problems, but arcing caused by contact failure is difficult to detect in advance. This study used an IR sensor to detect the heat concentration caused by the arc. The data from the low-resolution sensor was amplified as much as four times by interpolation to find the exact location of the heat source and were then investigated.

• Journal of Oral Medicine and Pain
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• v.7 no.1
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• pp.77-85
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• 1982

Identification of blood group from dental hard tissue for the purpose of individual identification of a highly burned corpse would play a significant role in a practical legal medicine. The author conducted a study of blood group with teeth left stading at a high temperature by the method of elution test. The following results were obtained. 1. The blood identifcation from heated dental hard tissue proved to be possible. 2. In cases of heat-treated theeth at $100^{\circ}C$ for 120 minutes, at $150^{\circ}C$ for 120 minutes and at $200^{\circ}C$ for 45 minutes for A.B.O(H) blood group, the identification of blood group was possible. 3. In case of heat-treated teeth, thermostability of blood group was found to be $150^{\circ}C$. 4. The adequate surface area for the detection of blood group was 40-80 meshes.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.3
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• pp.200-206
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• 2010

In ultrasound-excited thermography, the injected ultrasound to an object is transformed to heat and the appearance of defects can be visualized by thermography camera. The advantage of this technology is selectively sensitive to thermally active defects. Despite the apparent simplicity of the scheme, there are a number of experimental considerations that can complicate the implementation of ultrasound excitation thermography inspection. Factors including acoustic horn location, horn-crack proximity, horn-sample coupling, and effective detection range all significantly affect the detect ability of this technology. As conclusions, the influence of coupling pressures between ultrasound exciter and specimen was analyzed, which was dominant factor in frictional heating model.

• Advances in nano research
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• v.16 no.2
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• pp.201-215
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• 2024

The present research study emphasizes the utilization of mathematical simulation on a nanoelectromechanical systems (NEMS) sensor to facilitate the detection of injuries in players and equipment. Specifically, an investigation is conducted on the thermal buckling behavior of a small-scale truncated conical, cylindrical beam, which is fabricated using porous functionally graded (FG) material. The beam exhibits non-uniform characteristics in terms of porosity, thickness, and material distribution along both radial and axial directions. To assess the thermal buckling performance under various environmental heat conditions, classical and first-order nonlocal beam theories are employed. The governing equations for thermal stability are derived through the application of the energy technique and subsequently numerically solved using the extended differential quadratic technique (GDQM). The obtained results are comprehensively analyzed, taking into account the diverse range of effective parameters employed in this meticulous study.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.548-553
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• 2011

The lock-in thermography was employed to evaluate the defects in railway bogies. Prior to the actual application on railway bogies, in order to assess the detectability of known flaws, the calibration reference panel was prepared with various dimensions of artificial flaws. The panel was composed of polymer matrix composites, which were the same material with actual bogies. Through lock-in thermography evaluation, the optimal frequency of heat source was determined for the best flaw detection. Based on the defects information, the actual defect assessments on railway bogie were conducted with different types of railway bogies, which were used for the current operation. In summary, it was found that the novel infrared thermography technique could be an effective way for the inspection and the detection of surface defects on bogies since the infrared thermography method provided rapid and non-contact investigation of railway bogies.