• Proceedings of the KSRS Conference
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• v.1
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• pp.504-507
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• 2006

Airborn Lidar technology has been applied to diverse applications with the advantages of accurate 3D information. Further, Lidar intensity, backscattered signal power, can provid us additional information regarding target's characteristics. Lidar intensity varies by the target reflectance, moisture condition, range, and viewing geometry. This study purposes to generate normalized airborne LiDAR intensity image considering those influential factors such as reflectance, range and geometric/topographic factors (scan angle, ground height, aspect, slope, local incidence angle: LIA). Laser points from one flight line were extracted to simplify the geometric conditions. Laser intensities of sample plots, selected by using a set of reference data and ground survey, werethen statistically analyzed with independent variables. Target reflectance, range between sensor and target, and surface slope were main factors to influence the laser intensity. Intensity of laser points was initially normalized by removing range effect only. However, microsite topographic factor, such as slope angle, was not normalized due to difficulty of automatic calculation.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1986.10a
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• pp.194-197
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• 1986

In this paper, for the curvature correction on the scanning plane in laser scanning system, aberration correction method using holographic optical element is suggested. Holoens is selected as a type of holographic zone plate which has aberration correction property. And hologram recording condition is analyzed to find fo property. This hololens is implemented by computer-generated hologram technique. Laser scanning system is organized using desinged hololens and scanning properties of this system are investigated. Using this method optical system structure in laser scanning system can be simplified satisfying both scan linearity and field flatness.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.3
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• pp.235-241
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• 2007

This paper proposes a self-calibration method of robots those are used in industrial assembly lines. The proposed method is a position compensation using laser sensor and vision camera. Because the laser sensor is cross type laser sensor which can scan a horizontal and vertical line, it is efficient way to detect a feature of vehicle and winding shape of vehicle's body. For position compensation of 3-Dimensional axis, we applied block interpolation method. For selecting feature point, pattern matching method is used and 3-D position is selected by Euclidean distance mapping between 462 feature values and evaluated feature point. In order to evaluate the proposed algorithm, experiments are performed in real industrial vehicle assembly line. In results, robot's working point can be displayed 3-D points. These points are used to diagnosis error of position and reselecting working point.

• Journal of ILASS-Korea
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• v.7 no.2
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• pp.1-6
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• 2002

It is necessary to develope a high frequency diode laser sensor system based on the absorption spectroscopy for the measurement of temperature of the spray flame. DFB diode laser operating near $2.0{\mu}m$ was used to scan over selected $H_2O$ transitions near $1.9{\mu}m\;and\;2.2{\mu}m$, respectively. The measurement sensitivity at wide range of sweep frequency was evaluated using multi-pass cell containing $CO_2$ gas. This diode laser absorption sensor with high temporal resolution up to 10kHz was applied to measure the gas temperature in the spray flame region of liquid-gas 2-phase counter flow flame. The successful demonstration of time series temperature measurement in the spray flame gives us motivation of trying to establish non-intrusive temperature measurement method in the practical spray flame.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.967-968
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• 2007

This report is the study for laser scanning. Scanning control of $CO_2$ laser, He-Ne laser, used for the treatment of body skin, has relatively low band about hundered Hz. It could be used as a substitiute for expensive galvanometer that is the established scan method, which operates the number of KHz movement by using step motor when it operates low speed. To increase the accuracy of step motor's the angle of rotation, We could materialize 100Hz low band by using open loop, closed loop method with microprocessor. This causes it to be stable even direction by attaching electric capacity sensor. Therefore, We could expect to reduce the cost by manufacturing low band scanner rather than costly feedback galvanometer.

• Korean Journal of Veterinary Research
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• v.44 no.3
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• pp.475-482
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• 2004

For the induction of arthropathy, 4% hydrogen peroxide ($H_2O_2$) was injected for 4 weeks into the intra-articular space of the 25 New Zealand white rabbits to damage articular cartilage. The verification of arthropathy induction and the effect of scan-bio laser treatment were determined by measuring superoxide dismutase (SOD) activity, by observing gross and histopathologic findings. The SOD activity increased by about 40% in arthropathy group, as compared to controls. Although SOD activity in arthropathy group was not significantly different from the 2-week group, it was significantly different from the 4-week control and treatment groups. There was also a significant difference between the 4-week control and treatment groups. Grossly, erosions formed on the articular cartilage surface, and the lateral femoral condyle was damaged in arthropathy group. In comparison, there was slight, but not significant, progression of the lesion in the 2-week control group, and no difference between the 2-week treatment and control groups. Conversely, severe erosions damaged the articular cartilage in the 4-week control group. Cartilage proliferation was seen in gross observations in the 4-week treatment group, suggesting a treatment effect. Histopathologically, there was slight articular surface damage and apoptosis in arthropathy group, and serious cartilage damage, despite slight chondrocyte proliferation, in the 4-week control group. By contrast, the 4-week treatment group showed chondrocyte replacement, with close to normal articular cartilage on the articular surface. There was significant cartilage proliferation with regeneration of the articular cartilage on the articular surface in the group treated with low-level laser, as compared to control group, when arthropathy was induced by $H_2O_2$ injections. Therefore, low-level laser was effective in the treatment of chemically induced arthropathy.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.5
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• pp.468-472
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• 2013

This paper deals with the indoor localization problem for a SSMR (Skid Steering Mobile Robot) subjected to wheel-ground friction and with one LRF (Laser Range Finder). In order to compensate for some friction effect, a friction related coefficient is estimated by the recursive least square algorithm and appended to the maneuvering command. Also to reduce odometric information based localization errors, the lines are extracted with scan points of LRF and matched with the ones of the corresponding map built in advance. The present friction compensation and scan map matching schemes have been applied to a laboratory SSMR, and experimental results are given to validate the localization performance along an indoor corridor.

• Journal of Biosystems Engineering
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• v.42 no.3
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• pp.170-189
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• 2017

Purpose: This paper presents Raman chemical imaging technology for inspecting food and agricultural products. Methods The paper puts emphasis on introducing and demonstrating Raman imaging techniques for practical uses in food analysis. Results & Conclusions: The main topics include Raman scattering principles, Raman spectroscopy measurement techniques (e.g., backscattering Raman spectroscopy, transmission Raman spectroscopy, and spatially offset Raman spectroscopy), Raman image acquisition methods (i.e., point-scan, line-scan, and area-scan methods), Raman imaging instruments (e.g., excitation sources, wavelength separation devices, detectors, imaging systems, and calibration methods), and Raman image processing and analysis techniques (e.g., fluorescence correction, mixture analysis, target identification, spatial mapping, and quantitative analysis). Raman chemical imaging applications for food safety and quality evaluation are also reviewed.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.9
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• pp.70-76
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• 1996

In the Stereolithography process, three-dimensional objects are built by sequentially curing, generated by horizontal slicing of a three-dimensional CAD model. The dimensional accuracy of a menufactured part depends on the accuracy of curing performed by laser beam radius and the half of curing width. When offsetting, some slices have collinear segments, coincident vertices, line jerks and open loops. After remove above issues we have correct offsets data. And in last step, these data are used to scan paths.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1849-1851
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• 1999

The PDP(Plasma Display Panel) barrier rib was fabricated by focused $Ar^+$ laser ($\lambda$=514nm) and Nd:YAG($\lambda$=532, 266 nm) laser irradiation. The depth of the etched groove increases with increasing a laser fluence. and decreasing a scan speed. Using the second harmonic of the Nd:YAG laser, the threshold laser fluence was $6.5mJ/cm^2$ for the sample of PDP barrier rib dried at $120^{\circ}C$. The thickness of $150{\mu}m$ of the sample on the glass was etched without any damage on the glass substrate by fluence of $19.5J/cm^2$. The barrier rib sample on hot plate was etched by Nd:YAG laser(532 nm) as increasing a temperature of the sample. In this case, the etch rate was $95{\mu}m/s$, $190{\mu}m/s$ at room temperature, $175^{\circ}C$ respectively.