• 천문학회보
• /
• 제37권1호
• /
• pp.78.1-78.1
• /
• 2012

We present near-IR imaging polarimetry of the 5${\times}$9 fields (-39'${\times}$69') centered at 30 Doradus in the Large Magellanic Cloud (LMC), using the InfraRed Survey Facility (IRSF). We obtained polarimetry data in J, H, and Ks bands using the JHKs-simultaneous imaging polarimeter SIRPOL in 2008 December and 2011 December. We measured Stokes parameters of point-like sources to derive the degree of polarization and the polarization position angle. Since our results are suffered from non-photometric weather, we compare the polarization results from 2008 and those from 2011, and examine the photometric reliabilities between the two runs. Our survey data will be compared with molecular and dust maps to reveal the large-scale magnetic field properties in the star-forming clouds.

• 천문학회보
• /
• 제42권2호
• /
• pp.83.2-83.2
• /
• 2017

We report observations of light bridge (LB) jets taken with the New Solar Telescope. Jets as dark, fine threads occurred lined along both edges of a LB of a sunspot, which is a bright and elongated structure that divides a sunspot's umbra into two or more parts. This LB jets are observed for about three hours with $H{\alpha}$ filtergraph at ${\pm}0.4{\AA}$, ${\pm}0.8{\AA}$ from the line center, TiO filtergraph, and near infra-red imaging spectropolarimeter (NIRIS). High resolution $H{\alpha}$ data revealed that subsequent ejection of LB jets were associated with subsequent brightening along the edge of the LB. Also, this subsequent brightening was spatially correlated with both photospheric flow and magnetic field change detected from the TiO and NIRIS data, respectively. Preliminary results of LB jet observation and discussions on its formation mechanism will be presented.

• 센서학회지
• /
• 제20권6호
• /
• pp.388-392
• /
• 2011

In this paper, a face detection method for interactive TV control system using a new feature, edge histogram feature, with a support vector machine(SVM) in the near-infrared(NIR) images is proposed. The edge histogram feature is extracted using 16-directional edge intensity and a histogram. Compared to the previous method using local binary pattern(LBP) feature, the proposed method using edge histogram feature has better performance in both smaller feature size and lower equal error rate(EER) for face detection experiments in NIR databases.

• Journal of the Korean Wood Science and Technology
• /
• 제26권2호
• /
• pp.51-58
• /
• 1998

Structural changes of cellulosic fibres during the papermaking process were studied by analysis of FTIR spectra collected by the transmission method. The spectra were obtained from a carefully prepared handsheet, using a special infra-red (IR) cell suitable for evacuating the sample. The deconvolution technique was also applied for sharpening the FTIR spectra in the frequency range of the OH and CH stretching bands, which gave detailed information on the structural changes of cellulose. The intensity of some bands was decreased by predrying the sample as a result of the removal of adsorbed moisture. An increase in intensity of some bands in the frequency range of 3700 to $3200cm^{-1}$ was shown at a higher beating level. This increase in intensity was caused by changes in the crystal domain of cellulose resulting from the exposure of the crystalline area on the fibre surface.

• 천문학회지
• /
• 제40권4호
• /
• pp.113-118
• /
• 2007

Recently far infra-red (FIR) polarization of the $850{\mu}m$ continuum emission from T Tauri disks has been detected. The observed degree of polarization is around 3 %. Since thermal emission from dust grains dominates the spectral energy distribution at the FIR regime, dust grains might be the cause of the polarization. We explore alignment of dust grains by radiative torque in T Tauri disks and provide predictions for polarized emission for disks viewed at different wavelengths and viewing angles. In the presence of magnetic field, these aligned grains produce polarized emission in infrared wavelengths. When we take a Mathis-Rumpl-Nordsieck-type distribution with maximum grain size of $500-1000{\mu}m$, the degree of polarization is around 2-3 % level at wavelengths larger than ${\sim}100{\mu}m$. Our study indicates that multifrequency infrared polarimetric studies of protostellar disks can provide good insights into the details of their magnetic structure.

• 천문학회보
• /
• 제35권1호
• /
• pp.59.1-59.1
• /
• 2010

We present wide-field near-IR imaging polarimetry of 30 Doradus, using the InfraRed Survey Facility(IRSF) 1.4 m telescope at the South African Astronomical Observatory. We obtained polarimetry data in J, H, and Ks bands using the JHKs-simultaneous imaging polarimeter SIRPOL. 30 Doradus is located in the Large Magellanic Cloud(LMC) and it is the most active starburst region known in the Local group of galaxies. 30 Doradus is one of the best field to examine the behavior of the interstellar medium and star-formation mechanism under different conditions. We will investigate the structure of magnetic field in 30 Doradus region.

• 한국마이크로전자및패키징학회:학술대회논문집
• /
• 한국마이크로전자및패키징학회 2003년도 기술심포지움 논문집
• /
• pp.270-277
• /
• 2003

Thermal performance of flip chip bonding with Sn-3.5Ag solder ball was studied. The temperature distribution was measured with IR(InfraRed) camera of 25 urn resolution. The measurement shows that most of the samples had much higher maximum temperature than average temperature. With central heater and 2.5 (W), the difference between maximum and average temperature is over $80^{\circ}C$. The distribution was influenced by the location of heater, the distance from heater to flip chip bonding, and the passivation opening of solder bumps. To reduce the maximum temperature, the bigger passivation opening, the smaller chip size, and the closer location of heater to flip chip bumps are preferrable.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
• /
• pp.329-334
• /
• 1987

The purpose of this study is to monitor and control the back bead width in arc welding with consumable electrode for reduction of the occurrence of weld defect. The temperature of a point on the weldment surface is selected, as a monitoring parameter, and measured by an optical infra-red sensor. The correlation between the back bead width and the surface temperature is experimentally obtained for various thicknesses of the weldment. The welding travel speed and the surface temperature are taken, respectively, as an input and an output of the welding process under the stable condition of arc. A PI control scheme to maintain the surface temperature at the desired level is proposed by the experimental study.

• 대한의용생체공학회:의공학회지
• /
• 제13권2호
• /
• pp.141-146
• /
• 1992

The propagation, reflection and scattering characteristics of the near Infra-red lights were experimented in order to check the feasibility of non-restrained biotelemetry using indirect transmitted light. The results of the experiments show that 3 kinds of walls examined are not specular reflectors but almost perfect diffuse surfaces with slight directivity and that light in a local point is spread out and fills the room uniformly by repeating the reflection and scattering at walls, ceiling, floor. These results also explain the fact that the diffusely reflected light can be utilized as the carrier of biotelemetry even after several scattering and reflections.

• Applied Science and Convergence Technology
• /
• 제23권4호
• /
• pp.161-168
• /
• 2014

A real-time monitoring of immersed antenna type inductively coupled plasma (ICP) was done with a homemade 2 dimensional voltage probe array to check the uniformity of the plasma. Measured voltage values with a high impedance voltmeter are close to the floating potential of the plasma. As the substrate carrier was moving into a magnetron sputtering plasma diffusive from a $125mm{\times}625mm$ size cathode, measured results showed reliably separation of plasma into the upper and lower empty space over the carrier. Infra red thermal imaging camera was used to observe the cross corner effect in situ without eroding a target to the end of the usage. 3 dimensional particle trace model was used to analyze the magnetron discharge's behavior.