• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.1-8
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• 2020

Air ducts installed for ventilation inside buildings accumulate contaminants during their service life. Robots are installed to clean the air duct at low cost, but they are still not fully automated and depend on manpower. In this study, an intersection detection algorithm for autonomous driving was applied to an air duct cleaning robot. Autonomous driving of the robot was achieved by calculating the distance and angle between the extracted point and the center point through the intersection detection algorithm from the camera image mounted on the robot. The training data consisted of CAD images of the duct interior as well as the cross-point coordinates and angles between the two boundary lines. The deep learning-based CNN model was applied as a detection algorithm. For training, the cross-point coordinates were obtained from CAD images. The accuracy was determined based on the differences in the actual and predicted areas and distances. A cleaning robot prototype was designed, consisting of a frame, a Raspberry Pi computer, a control unit and a drive unit. The algorithm was validated by video imagery of the robot in operation. The algorithm can be applied to vehicles operating in similar environments.

• Tunnel and Underground Space
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• v.22 no.1
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• pp.69-76
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• 2012

Theoretical backgrounds on the experimental methods of explosive welding, explosive forming and shock consolidation of powders are introduced. Explosive welding experiments of titanium (Ti) and stainless steel (SUS 304) plate were carried out. It was revealed that a series of waves of metal jet are generated in the contact surface between both materials; and that the optimal collision velocity and collision angle is about 2,100~2,800 m/s and $15{\sim}20^{\circ}$, respectively. Also, explosive forming experiments of Al plate were performed and compared to a conventional press forming method. The results confirmed that the shock-loaded Al plate has a larger curvature deformation than those made using conventional press forming. For shock consolidation of powders, the propagation behaviors of a detonation wave and underwater shock wave generated by explosion of an explosive are investigated by means of numerical calculation. The results revealed that the generation and convergence of reflected waves occur at the wall and center position of water column, and also the peak pressure of the converged reflected waves was 20 GPa which exceeds the detonation pressure. As results from the consolidation experiments of metal/ceramic powders ($Fe_{11.2}La_2O_3Co_{0.7}Si_{1.1}$), shock-consolidated $Fe_{11.2}La_2O_3Co_{0.7}Si_{1.1}$ bulk without cracks was successfully obtained by adapting the suggested water container and strong bonding between powder particles was confirmed through microscopic observations.

• Journal of Digital Convergence
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• v.11 no.4
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• pp.403-408
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• 2013

The configuration analysis for the image appeared in the storyboard as the 1st stage to change the scenario to the image expressed the visual phenomenon image starting from the literalism. The simultaneity of description on the interpretative level of the narrative description may describe various information multiple simultaneously, the relationship has been presented as a lot of these information has been weaved as one episode. The incident time of narrative description as the scene described mainly objectively and illustratively has been used usefully to present the accurate information for characters or incidents. The time series of narrative description appeared as one episode by expressing various spaces or images under the continuity of flow according to the time. The collision image seen from the angle of internal ignition played a role to create the meaning colliding into each other or interconnecting symbolic effects appeared as respectively fragmented image, the continuity of space played a role of expressing the different symbol when the image of completely different space is connected to one context, the continuity of time as well makes a different symbolism by interpreting symbols appeared as each images under the flow of time. These results show that the narrative description may be expressed in accordance with the narrative structure from the viewpoints of narrative description, but the internal ignition may be interpreted through the cultural and periodical background widely known in those years based on the experience and information capability the audiences are keeping not by any descriptive structure. Images appeared in the internal ignition appeared by colliding into each other or amplifying mutually no related scenes and revealing the overall symbolism by reinterpreting again.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.1
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• pp.44-57
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• 2020

A dedicated short-range communications (DSRC) traffic information system is a detection system for a section of road using communication between roadside equipment and on-board High-Pass units to collect road traffic information and provide reliable traffic information to drivers. The Ministry of Land, Infrastructure, and Transport announced that a DSRC system must be supported to pass the performance evaluation of an intelligent transportation system (ITS), and the performance evaluation for DSRC systems installed in expressways and national highways is started. Currently, DSRC traffic information systems are only managed for maintenance and functional-monitoring purposes, which means that detailed criteria for the operation of a DSRC traffic information system, such as communication range, the direction of the antenna, and the power of the radio wave, etc., need to be established. In this paper, the criteria of the performance evaluation of a DSRC traffic information system are presented for different road types and road environments. The proposed performance evaluation criteria included the communication range and communication power of roadside equipment. In addition, installation criteria, such as the direction of the antenna, and the height and angle of the installed system, are presented for different road types and road environments. The criteria presented were evaluated for DSRC roadside equipment and documented to improve system maintenance and quality control of the communication system.

• Progress in Medical Physics
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• v.27 no.4
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• pp.250-257
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• 2016

The purpose of this study was to compare the patient setup errors of two different immobilization devices (Feet Fix: FF and Leg Fix: LF) for pelvic region radiotherapy in Tomotherapy. Thirty six-patients previously treated with IMRT technique were selected, and divided into two groups based on applied immobilization devices (FF versus LF). We performed a retrospective clinical analysis including the mean, systematic, random variation, 3D-error, and calculated the planning target volume (PTV) margin. In addition, a rotational error (angles, $^{\circ}$) for each patient was analyzed using the automatic image registration. The 3D-errors for the FF and the LF groups were 3.70 mm and 4.26 mm, respectively; the LF group value was 15.1% higher than in the FF group. The treatment margin in the ML, SI, and AP directions were 5.23 mm (6.08 mm), 4.64 mm (6.29 mm), 5.83 mm (8.69 mm) in the FF group (and the LF group), respectively, that the FF group was lower than in the LF group. The percentage in treatment fractions for the FF group (ant the LF group) in greater than 5 mm at ML, SI, and AP direction was 1.7% (3.6%), 3.3% (10.7%), and 5.0% (16.1%), respectively. Two different immobilization devices were affected the patient setup errors due to different fixed location in low extremity. The radiotherapy for the pelvic region by Tomotherapy should be considering variation for the rotational angles including Yaw and Pitch direction that incorrect setup error during the treatment. In addition the choice of an appropriate immobilization device is important because an unalterable rotation angle affects the setup error.

• The Journal of the Korea Contents Association
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• v.10 no.5
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• pp.115-123
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• 2010

Because of development of information technology, moving picture can run various platforms. We should consider and apply users' attitude as well as production technique because convergence between mobile and media technology may be increased full-browsing service using mobile device. Previous research related to production technique in various platforms only focus on video quality and adjustment of screen size. However, besides of technical side, production techniques should be changed such as image production as well as image editing by point of view aesthetic. Mise-en-scene such as camera angle, composition, and lighting is changed due to HD image. Also image production should be changed to a suitable full-browsing service using mobile device. Therefore, we would explore a new suitable production techniques and image editing for smart phone. To propose production techniques for smart phone, we used E-learning production system, which are transition, editing technique for suitable converting system. Such as new attempts are leading to new paradigm and establishing their position by applying characteries such as openness, timeliness to mobile. Also it can be extended individual area and established as expression and play tool.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.183-190
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• 2014

Since Scenic Sites, heritages to protect the value of landscapes, include valleys and mountains, the cultural heritage protection zones and historical and cultural environments preservation districts are designated extensively. So the landscape protection effects of the designation of scenic sites should be examined. Accordingly, the purpose of this research is to present the methods of efficient institution of district for landscape protection of scenic sites. As the research subject, Cheongamjeong Pavilion and Seokcheongyegok Valley in Bonghwa (Scenic Site No. 60), which has the highest designation rate, was selected. The results of this research using the cumulative visibility technique of GIS are as follows. First, the method of selecting the viewpoint by preparing the reverse cumulative visibility from important landscape resources of the valley was presented. The reverse cumulative visibility can be utilized for rational selection of the viewpoint with regard to scenic sites. Second, the landscape analysis method in consideration of human viewing angle and the visibility of the background of landscape resources was developed. Third, the hierarchical landscape protection method of scenic sites utilizing cumulative visibility was presented. Fourth, it was established through on-site inspections that the method of institution of district is the practical method.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.1
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• pp.65-74
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• 2018

The aim of this study was to obtain the traceability of the software used to analyze lateral cephalometry and to calculate the uncertainty of the measurements. Furthermore, this study aimed to provide a basis for obtaining standard references for measurement values for orthodontic treatment in children. Cephalometric data were collected from 100 children diagnosed with class I malocclusion between the ages 6 to 13 years who visited the pediatric dentist at Seoul National University Dental Hospital. To ensure traceability, a phantom device was created. Correction values were calculated by measuring the length and angle of the phantom device using the software. Type A uncertainty was calculated by obtaining the standard deviation of cephalometric measurements of 100 persons and the standard error of repeated measurements. Determination of the type B uncertainty was induced by minimum resolution and the position of the head. Using these, the combined standard uncertainty was obtained and the expanded uncertainty was calculated. The results of this study confirm that the currently used software has high accuracy and reliability. Furthermore, the uncertainty of orthodontic measurements in Korean children aged 6 to 13 years was calculated, and distribution range for class I malocclusion with 95% confidence interval was suggested.

• Journal of Digital Convergence
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• v.16 no.1
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• pp.287-292
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• 2018

The digital multimedia environment, centered on Information and Communications Technologies (ICT) technology, has transformed our imagination into a diverse experience. The flexible display, which was born as a means of human-machine communication required in a highly information-oriented society, It is creating a new market by linking with Internet of things. ecause the interface of a flexible display can provide a physical form as a result of input or output, user-centered interface design is paramount. Therefore, the researchers of this paper have studied the physical deformation and characteristics of flexible display by user manipulation through literature and case studies. Therefore, the authors of this paper studied the physical deformations and characteristics of flexible displays by user manipulation through literature and case studies. This research suggests the following guidelines for a flexible display interface design for the user experience. First, it must be designed to provide the functionality that users need in a variety of display environments. Second, in using the interface, external factors should be removed from the viewing angle of multi-users. Third, all possible user actions should be considered on flexible displays other than touch and contact. Fourth, flexible design of flexible display requires changing interface design for user experience.

• Journal of Digital Convergence
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• v.15 no.4
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• pp.275-284
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• 2017

TACAN(TACtical Air Navigation) was created to support military aircraft's short range navigation (200~300 mile). TACAN must fulfill a condition of MIL-STD-291C, the U.S. Military Standards, which addresses the sum of 15Hz and 135Hz should be within 55%, following the factor of modulations for both to be $21{\pm}9%$ each. Within the existing TACAN antenna, modulation factor for 15Hz and 135Hz are created differently depending on its diameter, wavelength, angle of gradient, internal modulation method or using frequency code. It brings up a problem where applications needed to be stopped and repaired when modulating signal exceeds the standard of MIL-STD-291C since the existing TACAN antenna does not have coordination function. Hence, plan and produce a modulating signal generator using FPGA, and check the changes in the modulation factor for 15HZ and 135Hz, depending on the values that have been set in each criteria. Moreover, allow the modulating signal generator to be automatically adjusted based on the monitoring signal emitted by antenna, and place alarm sound just in case if it exceeds the standard.