• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.286-288
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• 2003

In this paper, we present our implementation of the direct camera model (image to ground) for SPOT5 and use it to assess the geometric accuracy of SPOT5 imagery. Our assessment confirms the location accuracy of SPOT5 imagery (without use of GCPs) is less than 50m. We further introduce a few attitude parameters to refine the camera model with GCPs. The model is applied to two SPOT5 supermode images, one near vertical, incidence angle of 3 degrees, and one far oblique, incidence angle of 27 degrees. The results show that accuracy (rms of check points) of about one pixel (2.5m) can be achieved with about 4 GCPs by using only 3 parameters to correct the yaw, pitch and roll of the satellite.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.591-595
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• 1990

This paper describes a method of aisle following of a mobile robot using machine vision. As a navigation guide, Black strip painted on the lower part of wall of aisle is used. The offset of the vehicle position from the center of aisle and the heading angle are determined from the binary image of guide strip captured by a CCD camera. To remove the effect of noise. i.e. break of guide strip for the door or reflection of light, pixel sampling method together with consistency check of the incline for the sampled pixels is used.

• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.44-50
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• 1997

As jumpers for overhead transmission lines increase In size, it Is necessary to take into the characteristics of jumper swaying space in order to determine jumper reinforcements adequately. From the theory of a structure made of beams, formulas for the sideway swaying of overhead transmission lines due to wind are modeled. And also natural frequency of the vibrated jumper is estimated to check the system resonance. The theoretical results can be led good suggestions to improve the economy and reliability of jumper structure.

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.177-178
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• 2005

The load/unload behavior of the hard disk drive slider is studied in terms of the air bearing static characteristics. The numerical continuation methods are applied to calculate suspension force - equilibrium position curve. The critical preloads of the femto size slider are analyzed. The hi-stability conditions are depicted on the skew angle - preload diagram. The perturbation method is used to check the stability of the solution branches.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1418-1419
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• 2007

In order to check the electric field distribution of polymer line post insulator, we performed electric field simulation according to state of water drops. Sea water is used to the contaminant. Electric field analysis is performed with change of contact angle, number and distance of water drops.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.3
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• pp.43-48
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• 2018

Offset parabolic antenna have been widely used for satellite communication system. To locate feedhorn on antenna system, it requires arbitrary structure which forces to fix on system. However, arbitrary scatterer increases sidelobe level of elevation axis. To solve this problem, we need to predict which angle level is increased by arbitrary scatterer simply. Because conventional simulation method takes a long time to simulate parabolic antenna system and needs exclusive software. In this paper we can calculate sidelobe angle simply by using raytracing method, check coincidence between calculated and simulated result and show how arbitrary scatterer affects sidelobe lavel of elevation axis of offset parabolic antenna depending on angle and location of arbitrary structure.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.4
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• pp.269-274
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• 1993

This is the case report of huge complex odontoma treated with sagittal splitting of buccal bone plate and iliac bone graft in left mandible angle. The 22 years old patient was admitted to the department of Oral and Maxillofacial Surgery of Kyungpook National University Hospital with the chief complaint of swelling on the left mandible angle area. We used extra oral Risdon incision and splitted the buccal cortical bone after making the horizontal bone cut buccally. The tumor mass was removed with cutting into the pieces with surgical bur to prevent mandibular fracture. The dead space was grafted with autogenous iliac bone graft and the splitted buccal cortical bone was fixed with two L-type miniplate. After 12months follow up check, we noticed good process of bone healing and satisfactory aesthetic result. In this case, my operative approach provided the excellent surgical access to the hard tissue mass and minimized post operative complication comparing with the conventional surgical approaches.

• Korean Journal of Materials Research
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• v.28 no.4
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• pp.221-226
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• 2018

The property changes of 18, 14, and 8K green gold alloys for jewelry are observed by adding 0.0, 3.0, and 5.0 wt% of indium (In), respectively. To check the composition of the alloys, an energy dispersive spectroscopy (EDS) analysis is conducted. Color and microstructure analysis is executed through bare-eye, macro camera, UV-VIS-NIR-colormeter, and optical microscope. The melting point, wetting angle, and hardness are measured using TGA-DTA, a wetting angle tester, and a Vickers hardness tester. The EDS analysis result demonstrates that each of the green gold alloys was manufactured with purposed contents. The color analysis result shows that the color of the alloys is similar to the color of the conventional 4 wt%-Cd 18K green gold, and the green color improves as the In content increases. The micro structure analysis result demonstrates that grain refinement improves as the amount of In increases. Enhancements in the melting point, wettability, and Vickers hardness changes appear as the In content increases and Au content decreases. The hardness is up to 260, which implies good durability. Therefore, the results suggest that the proposed 18, 14, and 8K In-added green gold alloys enhance the properties of jewelry products with regard to the green color, castability, and durability.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.1
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• pp.220-224
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• 2010

In this study, we designed a device for consecutively observing position, utilizing 3-axises acceleration sensor. This method offer to check his or her wrong position and developed could to help derived a position appliance. And, we developed a Cobb's angle value in three dimensional using 3-axises acceleration sensor. A proposed device with integrated accelerometers, which can detect postural changes in terms of curvature variation of the spine in the sagittal and coronal planes, has been developed with intention to facilitate posture training. The proposed device was evaluated with 3 normal subjects daily activities. We evaluated the performance of our designed device as calculating the correlation coefficients and mean errors between the angle measured by an electro-goniometer and that estimated by a gravity accelerometer and verified the accuracy and sensitivity. The results showed that the angle obtained from the proposed device revealed a linear characteristic at the range of $\pm60^{\circ}$(correlation coefficient 0.99, error range $\pm2^{\circ}$). We demonstrated that our device could detect the changes of the motion in upper trunk accurately. Also, our device showed good potential for treatment of the patients with scoliosis and prevention of the unbalance position during a daily life.

• Korean Journal of Optics and Photonics
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• v.13 no.2
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• pp.166-170
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• 2002

Reflectors for reflective LCDs must be designed to be able to control the direction of the image and the viewing angle range for optimal display. In this paper, we tried to optimize the reflector for reflective LCDs. The conventional surface structures showed many defects and problems. Therefore we made efforts to improve the surface structures of the conventional reflectors through both a theoretical approach and analytic work. As a result, we proposed surface structures which showed almost uniform reflectance within the viewing angle range specified by a user even at any oblique incidence. By using Beckmann's equations, we could check the reflective property of the proposed surface structures.