• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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• pp.98-105
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• 2015

Demands of thermal recording paper have been increased significantly by increase in usage of invoice, fax, and label. Thermal recording paper was mainly made based on virgin fiber. It is necessary to find a suitable alternative to virgin fiber in terms of environment protectional resources conservation. In this paper, deinking properties of different recovered papers were analyzed in order to use the recovered paper as raw material of thermal recording paper. Recovered paper were ONP, OMG and white ledger. Flotation reject of OMG was high because inorganic pigments in coating layer could be removed by upstream of froth. Brightness of white ledger and OMG were much higher than that of ONP. Therefore, properties of pulp made from the recovered paper could be enhanced with increase in blending ratio of white ledger and OMG. However, blending ratio of OMG caused the increase of flotation reject. Consequently, the optimum blending ratio of ONP, OMG, and white ledger was 3:3:3 for eco-friendly thermal recording paper. Under the condition, brightness was about 70% and ERIC was below 300 ppm.

• Journal of Korea Multimedia Society
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• v.23 no.6
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• pp.738-746
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• 2020

In this paper, we propose an indirect PIN entry method that provides enhanced security against smudge, recording, and thermal attacks. Conventional mobile PIN entry methods use on-screen numeric keypad for both use of display and entry. Thus These methods are vulnerable to aforementioned attacks. In our method, passcode is same as that of the conventional PIN entry methods, and that is user-friendly way for mobile device users. Therefore, our method does not reduce user convenience which is one of the advantages of the conventional methods. In addition, our method is not a method of directly touching the on-screen numeric keypad for entering passcode like the conventional PIN methods. Unlike the conventional methods, our method uses an indirect passcode entry method that applied a passcode indicating key. According to the performance comparison result, proposed method provides user convenience similar to the conventional methods, and also provides a higher level of security and safety against recording, smudge, and thermal attacks than the conventional methods.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.2
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• pp.202-208
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• 2008

Condition monitoring technologies allow achieving this goal by minimizing downtime through the integrated planning and scheduling of repairs indicated by condition monitoring techniques. Thermal runaways induced by conduction problems deteriorate insulating material and cause disruptive dielectric discharges resulting in arcing faults. Therefore, having the ability to directly measure the temperature of the contacts while in service will provide more information to determine the true condition of the equipment. It allows connective measures to be taken to prevent upcoming failure. Continuous temperature monitoring and event recording provides information on the energized equipment's response to normal and emergency conditions. On-line temperature monitoring helps to coordinate equipment specifications and ratings, determine the real limits of the monitored equipment and optimize facility operations. Using wireless technique eliminates any need for special cables and wires with lower installation costs if compared to other types of online condition monitoring equipment. In addition, wireless temperature monitoring works well under difficult conditions in strategically important locations. Wireless technology for on -line condition monitoring of energized equipment is applicable both as stand alone system and with an interface for power quality monitoring system. The paper presents the results of wireless temperature monitoring: of electrical equipment at a power plant.

• Transactions of the Society of Information Storage Systems
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• v.6 no.1
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• pp.12-17
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• 2010

Thermally-assisted magnetic recording (TAMR) is a potentially promising approach to increase the storage density of hard disk drive (HDD). However, TAMR has some issues such as temperature effects, media problems, thermal deformation and light delivery. In this research, we focused on light delivery. One of the powerful methods to deliver the light from laser diode to recording medium is the use of an optical fiber and a specially designed prism. However, the TAMR with optical fiber may have some flyability problems induced by the mounted optical fiber and prism. Also, the TAMR suspension using an optical fiber has high vertical and pitch stiffness. Therefore, p-torque is greatly increased by the optical fiber. Also, flying height (FH) of the slider with TAMR suspension can be largely changed by p-torque. Therefore, in this paper, we focus on the pitch static attitude (PSA) tolerance and the FH by PSA of the TAMR suspension. The FH is investigated using various errors and the PSA tolerance for TAMR suspension is proposed.

• Proceedings of the KWS Conference
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• 2006.05a
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• pp.148-150
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• 2006

In this paper, the applicability of an UET(ultrasound excited thermography) for a defect detection of the welded receptacle is described. An UET(ultrasound excited thermography) is a defect-selective and fast imaging tool for damage detection. A high power ultrasound-excited vibration energy with pulse durations of 280ms is injected into the outer surface of the welded receptacle made of Al material. An ultrasound vibration energy sent into the welded receptacle propagate inside the sample until they are converted into the heat in the vicinity of the defect. The injection of the ultrasound excited vibration energy results in heat generation so that the defect is turned into a local thermal wave transmitter. Its local heat emission is monitored by the thermal infrared camera. And they are processed by the image recording system. Measurement was performed on aluminum receptacle welded by using Nd:YAG laser. The observed thermal image revealed two area of defects along the welded seam.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2003.11a
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• pp.47-51
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• 2003

In this paper, we compared the thermal environment in the livingroom with panel heating system of Korea and Japan. The houses are two apartments and two single houses in Korea, and two apartments in Japan. The outdoor temperatures, indoor air temperatures, surface temperatures on floor and humidities were measured. The survey to the residents and recording of operation were also collected. The results were as follows.1. The Korean houses are warmer and drier(approximately 23$^{\circ}$C, 38%) than those of Japan.(approximately 20$^{\circ}$C, 57%). And indoor temperaures of Korean apartment are stabie. 2.The residents in Japan put on and off the switches of the heating system frequently.

• Journal of Magnetics
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• v.2 no.2
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• pp.58-66
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• 1997

Recently, artificially modulated magnetic multilayer materials, for examples giant magnetoresistant magnetic head materials and magneto-optic recording materials in the wavelength of a blue laser beam, attract great attention in the electronics industry due to their unique properties derived from the modulated multilayer structure. Since the multilayer structure as well as amorphous structure, is non-equilibrium state in terms of free energy, an assessment of the thermal staibility in the multilayer structure is crucially importnat both for basic research and applications. In this review paper, effective microscopic interdiffusion process in the two dimensional multilayer structure will be described in terms of steep concentration gradient effect, strain effect and magnetic transition effect.

• Korean Journal of Optics and Photonics
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• v.16 no.2
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• pp.121-127
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• 2005

This paper presents the thermal characteristics of a Bragg grating recorded in photopolymer. We record hologram gratings using a 532 nm Nd : YAG laser in DuPont HRF 150-38 photopolymer films and analyze the diffraction efficiency versus thermal exposure conditions. For the case of recording after heating, the diffraction efficiency of the hologram is more than $70\%$ at $100^{\circ}C$ but is decreased exponentially at temperatures over $100^{\circ}C$. It is observed in the recording before heating that the diffraction efficiency of the hologram fixed by a UV light is increased to approximately $10\%$ at $100^{\circ}C$, but the holograms are erased at temperatures over $120^{\circ}C$.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.379-381
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• 1994

Volume holograms recorded in photorefractive materials can find important applications in optical memories and optical computing systems. One problem with a photorefractive hologram is that it gets erased by the readout light. Nondestructive readout can be achieved by hologram fixing, and several fixing methods have been reported. Fixing is accomplished by thermally activated motion of an unknown ionic defect, which neutralizes the electronic space-charge patterns. At room temperature the ionic patterns are stabilized. When the electrons are partially redistributed by light, a net space-charge pattern appears, and tile fixed hologram can be read out. In this paper, theoretical modeling and some experimental results are presented for thermal fixing of volume phase holograms in photorefractive $LiNbO_3$:Fe. Thermal fixing can be done during or after recording and depends on fixing temperature ($100{\sim}200^{\circ}C$ range) and grating length. Fixed Slating can be erased completely at the temperature over $300^{\circ}C$. Theoretical modeling shows weil the compensation of electronic Slating by ionic grating and is in good agreement with experimental results. In experiments the dependence of thermal fixing on temperatures and grating lengths is investigated.

• Journal of the Korean Magnetics Society
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• v.10 no.5
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• pp.232-236
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• 2000

CoSm thin films with a Cr underlayer have received continuous attention as a potential material for a high density longitudinal magnetic recording media. In this study the Ax gas sputtering pressure effects on the magnetic properties of CoSm thin films, which were fabricated by using a dc magnetron sputtering machine, were investigated. The magnetic switching volume is especially important parameter to understand the thermal stability of the written information, magnetization reversal process and media noise. Therefore, in this paper the effects of sputtering pressure on the magnetic switching volume of CoSm thin films grown on Cr underlayer with the same sputtering conditions was studied. As the Ar sputtering pressure during sputtering of the CoSm magnetic layer increases from 5 to 30 mTorr, the measured switching volumes decreased from 9.0 to 5.2$\times$10$^{-18}$ cm$^3$. The calculated diameter of switching unit from V＊ was less than 22 nm, which satisfies the Sharrock's requirement on the thermal stability of the high density longitudinal magnetic recording media.