• Journal of Magnetics
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• v.16 no.2
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• pp.83-87
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• 2011

The vortex-driven magnetization process of micron-sized, exchange-coupled square elements with composition of $Ni_{80}Fe_{20}$ (12 nm)/$Ir_{20}Mn_{80}$ (5 nm) is investigated. The exchange-bias is introduced by field-cooling through the blocking temperature (TB) of the system, whereby Landau-shaped vortex states of the $Ni_{80}Fe_{20}$ layer are imprinted into the $Ir_{20}Mn_{80}$. In the case of zero-field cooling, the exchange-coupling at the ferromagnetic/antiferromagnetic interface significantly enhances the vortex stability by increasing the nucleation and annihilation fields, while reducing coercivity and remanence. For the field-cooled elements, the hysteresis loops are shifted along the cooling field axis. The loop shift is attributed to the imprinting of displaced vortex state of $Ni_{80}Fe_{20}$ into $Ir_{20}Mn_{80}$, which leads to asymmetric effective local pinning fields at the interface. The asymmetry of the hysteresis loop and the strength of the exchange-bias field can be tuned by varying the strength of cooling field. Micromagnetic modeling reproduces the experimentally observed vortex-driven magnetization process if the local pinning fields induced by exchange-coupling of the ferromagnetic and antiferromagnetic layers are taken into account.

• Corrosion Science and Technology
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• v.2 no.2
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• pp.88-92
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• 2003

The technique for in situ simultaneous measurements of IR-RAS and QCM, which has been developed for investigation of corrosion in gaseous environments, was employed to study the effects of an extremely thin water layer on the corrosion rate. An evaporated copper film on a QCM element was exposed to air containing water vapor and $SO_2$, and time-resolved IR-RAS spectra were measured and mass gains were simultaneously followed with QCM. The tested ranges of relative humidity (RH) and concentration of $SO_2$ were 60% - 90% and 1 - 20 ppm, respectively. On the basis of 2D-IR analysis, the corrosion products were determined to be Chevreul's salt ($CuSO_3Cu_2SO_3{\cdot}2H_2O$) and $CuSO_4{\cdot}5H_2O$. By constructing curves of the relations between band intensities of IR spectra and mass gains of QCM for the corrosion products, the time variations in each product were determined from spectral experiments on copper plates. The thicknesses of physically adsorbed water layers in course of the corrosion process were also determined from water band intensities. The results showed that the thickness of the physically adsorbed water layer increased with increase in RH, and it also increased with increase in accumulation of corrosion products. The latter is probably due to the capillary effect of the corrosion products.

• Journal of Adhesion and Interface
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• v.15 no.1
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• pp.1-8
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• 2014

Ion exchange membrane is widely used in various fields such as electro dialysis, diffusion dialysis, redox flow battery, fuel cell. PVC cation exchange membrane using ultrasonic modification was prepared by sulfonation reaction in various sulfonation times. Sulfuric acid was used as a sulfonating agent with ultrasonic condition. We've characterized basic structure of sulfonated PVC cation exchange membrane by FT-IR, EDX, water uptake, ion exchange capacity (IEC), electrical resistance (ER), conductivity, ion transport number and surface morphology (SEM). The presence of sulfonic groups in the sulfonated PVC cation exchange membrane was confirmed by FT-IR. The maximum values of water uptake, IEC, electrical resistance and ion transport number were 40.2%, 0.87 meq/g, $35.2{\Omega}{\cdot}cm^2$ and 0.88, respectively.

• Korean Journal of Veterinary Research
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• v.32 no.3
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• pp.333-339
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• 1992

The regional distribution and relative frequency of occurrence of endocrine cells in nine segments of the gastrointestinal(GI) tract of snakehead(Ophicephalus argus) were investigated by immunohistochemical methods using specific antisera against 5- hydroxyptrytamine(5-HT), somatostatin, gastrin/cholecystokinin(GAS/CCK), glucagon, bovine chromogranin, porcine chromogranin and insulin. Four types of immunoreactive cells for 5-HT, somatostatin, GAS/CCK and glucagon were observed in the GI tract. These cells were generally appeared in the mucosal epithelia or located at the interface of the mucosal epithelial layer and intestinal glandular region. 5-HT-immunoreactive(IR) cells were found in segment II, III, IV, V and VI, and the most numerous in segment IV. Somatostatin-IR cells were found in segment II, III, IV and V, and the most numerous in segment III. GAS/CCK-IR cells in segment VI, VII and glucagon-IR cells in segment III, IV, V were detected but a few in these segments. No bovine chromogranin-, porcine chromogranin- and insulin-IR cells were detected throughout the GI tract of the snakehead.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11S
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• pp.3410-3419
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• 1999

Autonomous Intrusion Analysis Agent(AIAA) is Incident Response Team staff's tool that scans, analyses, reports and alerts the traces of intrusion based on system logs and intruder's backdoors inside compromised system by IR staff after security incident is reported to the IR team. AIAA is intelligent to recognize to check out who is intruder from all the user accounts and to report the suspected candidates to the master control system in IR team. IR staff who controls AIAA with master system can pick up an intruder from the candidates reported by AIAA agent and review all related summary reports and details including source host's mane, finger information, all illegal behavior and so on. AIAA is moved to compromised system by the staff to investigate the signature of intrusion along the trace of victim hosts and it is also operated in secret mode to detect the further intrusion. AIAA is alive in all victim systems until the incident is closed and IR staff can control AIAA operation and dialogue with AIAA agent in Web interface.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1305-1307
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• 2007

We show that the electrical properties of organic thinfilm transistors(OTFTs) can be enhanced by controlling the morphology of interface between screen printed electrodes and gate dielectrics. Modified surface of the insulator layer($SiO_2$) affect on the interface energy of electrode on $SiO_2$ layer. Contact angle measurement and FT-IR spectrum shows that the interface is properly modified. OTFTs device with high efficiency has been realized through modification of interface layer.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.3 s.96
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• pp.78-83
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• 1999

The bonding interface is dependent on the properties of surfaces prior to SDB(silicon wafer direct bonding). In this paper, we prepared silicon surfaces in several chemical solutions, and annealed bonding wafers which were combined with thermally oxidized wafers and bare silicon wafers in the temperature range of $600{\times}1000^{\circ}C$. After bonding, the bonding interface is investigated by an infrared(IR) topography system which uses the penetrability of infrared through silicon wafer. Using this procedure, we observed intrinsic bubbles at elevated temperatures. So, we verified that these bubbles are related to cleaning and drying conditions, and the interface oxides on silicon wafer reduce the formation of intrinsic bubbles.

• Journal of the HCI Society of Korea
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• v.6 no.1
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• pp.1-8
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• 2011

As virtual realty has become an issue of providing immersive services, in the area of virtual realty, it has been actively investigated to develop user interfaces for immersive interaction. In this paper, we propose a gesture recognition based immersive user interface by using an IR LED embedded helmet and data gloves in order to reflect the user's movements to the virtual reality environments effectively. The system recognizes the user's head movements by using the IR LED embedded helmet and IR signal transmitter, and the hand gestures with the data gathered from data gloves. In case of hand gestures recognition, it is difficult to recognize accurately with the general recognition model because there are various hand gestures since human hands consist of many articulations and users have different hand sizes and hand movements. In this paper, we applied the Mixture-of-Experts based gesture recognition for various hand gestures of multiple users accurately. The movement of the user's head is used to change the perspection in the virtual environment matching to the movement in the real world, and the gesture of the user's hand can be used as inputs in the virtual environment. A head mounted display (HMD) can be used with the proposed system to make the user absorbed in the virtual environment. In order to evaluate the usefulness of the proposed interface, we developed an interface for the virtual orchestra environment. The experiment verified that the user can use the system easily and intuituvely with being entertained.

• Journal of the Semiconductor & Display Technology
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• v.19 no.3
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• pp.106-111
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• 2020

In this paper, we propose the non-contact gesture recognition system and algorithm using proximity-based sensors. The system uses four IR receiving photodiode embedded on a single chip and an IR LED for small area. The goal of this paper is to use the proposed algorithm to solve the problem associated with bringing the four IR receivers close to each other and to implement a gesture sensor capable of recognizing eight directional gestures from a distance of 10cm and above. The proposed system was implemented on a FPGA board using Verilog HDL with Android host board. As a result of the implementation, a 2-D swipe gesture of fingers and palms of 3cm and 15cm width was recognized, and a recognition rate of more than 97% was achieved under various conditions. The proposed system is a low-power and non-contact HMI system that recognizes a simple but accurate motion. It can be used as an auxiliary interface to use simple functions such as calls, music, and games for portable devices using batteries.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.7
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• pp.549-555
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• 2015

A measurement technique of interfacial velocity in air-water separated flow by particle tracking velocimetry using an infrared camera (IR-PTV) was developed. As infrared light with wavelength in the range of 3-5 um could hardly penetrate water, IR-PTV can selectively visualize only the tracer particles existing in depths less than 20 um underneath the air-water interface. To validate the measurement accuracy of the IR-PTV technique, a measurement of the interfacial velocity of the air-water separated flow using Styrofoam particles floating in water was conducted. The interfacial velocity values obtained with the two different measurement techniques showed good agreement with errors less than 5%. It was found from the experimental results obtained using the developed technique that with increasing air velocity, the interfacial velocity proportionally increases, likely because of the increased interfacial stress.