• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.11
• /
• pp.1653-1659
• /
• 2022

Virtual reality content provides users with a high sense of immersion by using HMD devices. However, while wearing the HMD device, it is difficult to determine the user's location or distance from obstacles, resulting in injuries due to physical collisions. In this paper, we propose a reminder module to prevent accidents by notifying the risk of collision with obstacles while wearing the HMD device. The proposed module receives the user's state from the acceleration and gyro sensor and determines the motion that is likely to cause a collision. If there is an obstacle in the expected collision range, a buzzer sounds to the wearer. As a result of the experiment, the accuracy of obstacle detection in the state of wearing the HMD was 86.6% in the 1st stage and 83.3% in the 2nd stage, confirming the performance of the accident prevention reminder.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.11 no.4
• /
• pp.411-420
• /
• 2016

Efforts have continued in recent years to research and develop new alternative energy sources to replace coal and oil. These days interest is exploding in new pollution-free renewable energy due to the rising prices of finite energy sources. In the field of solar energy, one of new renewable energy that has been actively researched and commercialized, research efforts have been focused on solar light energy, whose efficiency has, however, reached a saturation point already. Thus, this paper proposed a solar tracking-type parabolic heat collection device to utilize solar thermal energy rather than solar light energy. The proposed device was designed in a parabolic form to collect solar heat effectively. The investigator made its prototype by incorporating a five-axis censor-based solar tracking technology in it to sense changes to the location of the sun according to the seasons and periods. In addition, an administrator interface was designed and implemented for the efficient management of heat collection device.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.12
• /
• pp.2312-2317
• /
• 2017

Museums are converging with digital technology to convey information to viewers in various ways. Augmented reality technology enhances virtual objects seamlessly in the real world, and provides a high sense of immersion and realism because it can use various senses of users in combination with information providing role of exhibits. However, the location-based augmented reality may cause the inaccurate registration of the virtual object with the real world due to the error of the GPS information, and the vision-based augmented reality can be enhanced at the position where the marker is placed. To solve this problem, we implemented the exhibition contents that interact with the real world by using the developed project tango. The exhibited contents were based on Lenovo Phab 2 Pro and Project Tango SDK in Unity 3D. Visitors were able to improve immersion and realism in exhibition contents, and it would be able to combine with various exhibition fields such as shopping malls as well as museums.

• Korean Journal of Childcare and Education
• /
• v.8 no.2
• /
• pp.101-120
• /
• 2012

The purpose of this study was to investigate relationships between teachers' sense of self-efficacy and their job satisfaction to improve the quality of child care centers. It is crucial for teachers to have self-efficacy to reveal their potential for change and have opportunities to work better. In addition to teachers' self-efficacy, teachers' job satisfaction should be added to offer better child care service for parents as well as children. In this study, teachers' personalities and self-efficacy were compared between public and private child care centers to have further discussion making a progress of their job satisfaction. The results of this study are as follows : (a)The location of child care centers have meaningful effects on teachers' job satisfaction both in public and private child care centers equally. (b)Teachers in public child care centers have stronger influences on self-efficacy in home-related education and positive learning environment than teachers in private child care centers. (c)Teachers' participation in decision making is a significant factor that has affects on teachers' job satisfaction both in public and private child care centers.

• Journal of Astronomy and Space Sciences
• /
• v.34 no.4
• /
• pp.315-330
• /
• 2017

Halo coronal mass ejections (CMEs) originating from solar activities give rise to geomagnetic storms when they reach the Earth. Variations in the geomagnetic field during a geomagnetic storm can damage satellites, communication systems, electrical power grids, and power systems, and induce currents. Therefore, automated techniques for detecting and analyzing halo CMEs have been eliciting increasing attention for the monitoring and prediction of the space weather environment. In this study, we developed an algorithm to sense and detect halo CMEs using large angle and spectrometric coronagraph (LASCO) C3 coronagraph images from the solar and heliospheric observatory (SOHO) satellite. In addition, we developed an image processing technique to derive the morphological and dynamical characteristics of halo CMEs, namely, the source location, width, actual CME speed, and arrival time at a 21.5 solar radius. The proposed halo CME automatic analysis model was validated using a model of the past three halo CME events. As a result, a solar event that occurred at 03:38 UT on Mar. 23, 2014 was predicted to arrive at Earth at 23:00 UT on Mar. 25, whereas the actual arrival time was at 04:30 UT on Mar. 26, which is a difference of 5 hr and 30 min. In addition, a solar event that occurred at 12:55 UT on Apr. 18, 2014 was estimated to arrive at Earth at 16:00 UT on Apr. 20, which is 4 hr ahead of the actual arrival time of 20:00 UT on the same day. However, the estimation error was reduced significantly compared to the ENLIL model. As a further study, the model will be applied to many more events for validation and testing, and after such tests are completed, on-line service will be provided at the Korean Space Weather Center to detect halo CMEs and derive the model parameters.

• Fire Science and Engineering
• /
• v.24 no.4
• /
• pp.109-115
• /
• 2010

Maximum pressure difference in central core type 80th super_tall buildings was estimated as 75 Pa during no outside wind due to the winter stack effect. Maximum pressure difference of 225 Pa can be obtained depending on the location of air injection fan during the stairway pressurization at fire. Bottom_only air injection system provided the best results in the sense of required air flow rates and pressure distributions. Top_only air supply system was estimated as the worst for this country. It revealed that the decrease of the temperature in the stairway due to the cold outside air injection reduced the required flow rates of the fan and significantly changed the distribution of pressure differences.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.3
• /
• pp.1489-1494
• /
• 2013

Tsunami happens rarely enough to allow a false sense of security, but when they do occur, there may be just minutes or hours for people to reach a safe location. Natural disasters like tsunami are inevitable and it is almost impossible to fully recoup damages caused by the disasters. However, it is possible to minimize the potential risk by developing early warning strategies. GIS modelling with its geoprocessing and analysis capability can play a crucial role in efficient mitigation and management of disaster. This study aims at developing integrated spatial information system processing model supporting tsunami evacuation action planning using geo-information technology such as GIS. The integration process classified into four phases. And in each phase, required input data and GIS processes are decided. The main effort in minimizing casualties in tsunami disaster is to evacuate people from the hazard area before tsunami strikes by means of either horizontal or vertical evacuation. The study provides essential spatial information for local decision making related with people's evacuation in tsunami-prone areas based on a modeling approach transferable to other coastal areas.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.2 no.3
• /
• pp.33-41
• /
• 1982

Development is given for an analytical approach that can investigate parameters characterizing road network geometry. A grid transportation network having a hierarchy structure is considered on a homogeneous and isotropic urban plane in which trip origins and destinations are uniformly dispersed and the trip length distribution is independent of the location of the origin. The object is to find the optimal spacings between urban arterials so as to minimize the sum of travel and construction costs, subject to the hypothesis that a trip assignment follows the Wardrop's first principle. The proposed approach is not the genera method for determining an efficient network layout, but can be used as basic concept for generating and evaluating urban road network alternatives. Given an O-D table and cost estimates the approach is able to outline at least in a qualitative sense the optimal spacings of urban arterial roads.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.28 no.2
• /
• pp.23-36
• /
• 2010

The purpose of this study is to infer the aspects and significance of Musa basjoo of latter part of Chosun Dynasty by analyzing the planting tendency and planting location of Musa basjoos drawn in total 77 old paintings and the characteristics of the paintings where Musa basjoos appeared, while trying to understand symbolic meanings of floral languages as well as the images and significance of Musa basjoos which appeared in the prose and poetry of Chosun Dynasty, and the results are as follows; With its floral languages of 'waiting', 'parting' and 'beauty', Musa basjoo represented the wealth and resuscitation and it aroused the elegance of hermits in its Taoistic sense. And it also represented 'the unworldliness to get out of transient human affairs' in its Buddhistic sense. Musa basjoos which appeared in 'Garden Custom Painting(庭園雅集圖)', 'Gosa Figure Painting(故事人物圖)' and 'Gyehoe Painting(契會圖)' is considered a device to increase the unworldly atmosphere of gardens and to dignify the elegant meetings of scholars, reflected by the high appearance frequencies of cranes and deer. And it seems that the meaning of Musa basjoo in certain paintings like 'Life-time Paintings(平生圖)', 'Castle City Painting(盛市圖), and 'Cultivating and Weaving Painting(耕織圖)' is an aspiration for wealth and prosperity, and the Musa basjoos planted in temples are considered to have symbolic meanings of aspiration for 'Salvation through Belief' as well as a unworldly meaning which reminds the transiency of human affairs. In addition, the expected effect of experiencing 'the sound of rain falling on the leaves of Musa basjoo' has been pursued, which can be confirmed by the fact that Firmiana simlex with wide leaves similar to Musa basjoo can be frequently spotted near the houses. Meanwhile, Musa basjoos seem to have been planted mainly in front garden or side garden around detached house and Musa basjoos inside the houses seem to have been planted mainly in right side when viewed from the entrance, in relation with the location of bedrooms where it is easier to hear the sounds from the right side of the environment. And the paintings where Musa basjoos appear with strange rocks and bizarre stones among other things have greater part of all the paintings, which is considered a kind of intentional landscaping and a product of mixed materials for elegant appreciation. And the major characters of the painting were involved in the activities of scholars such as arts, and the activities of minor characters were greatly related to their everyday lives. Musa basjoo of Chosun Dynasty in $17^{th}$ and $18^{th}$ century was one of the symbols necessary for description of gardens. And it provided the images of rainy scenes together with scholar culture which had a meaning of self-discipline, and it is assumed that the planting of Musa basjoo with the spirit of cease lessen deavor of a new leaf pushing up the tree and the spirit of resuscitation had the same trace of wheels in the city space of our country as the decline of scholar culture of Chosun Dynasty.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.34 no.4
• /
• pp.37-50
• /
• 2016

Recognizing the problem of fallacy in geographical name of Changokbyeong(蒼玉屛), assumption has been made on the location of Changokbyeong through literature research on antique maps, ancient paintings, and old prose, through field survey on rock inscriptions and landscape characteristics, and through interviews with local people. Furthermore, Baegyeonwa, the Cuckoo Hut, and Iyangjung(二養亭), an annex to the cottage, both of which were managed by Saahm Park Soon(思菴 朴淳), the Subject of Jouissance, were studied in depth with emphasis on the spatial structure as well as special features of the area as a garden. The major findings are as follows: Changokbyeong is a spatial threshold that imparts a sense of unity with Okbyeng seowon(玉屛書院) and indeed Changokbyeong is presumed to have been the frontal river terrace of Okbyeng seowon according to the analysis of antique maps and rock inscriptions. This ancient location and the Ogari Stone Wall, the present day Changokbyeong, are only 460m away so that both areas are considered as falling under the influence of Changokbyeong landscape. The expression "Changokbyeong Geupsangeum(蒼玉屛及散襟)" written in an old prose tells us that the high rock wall with Sangeumdae inscribed on the rock might be the rock wall of Changokbyeong. In addition, while not a single rock inscription has been found on the Ogari Stone Wall, 11 rock inscriptions designed and ordered by Saahm Park Soon, the Subject of Jouissance, are found on every corner of the high rock wall standing in front of Okbyeng seowon, 8 of those 11 being place names and recitative poems(known as Jeyeongsi: 題詠詩) in close formation resembling the handwritings in a little notebook. This provides a strong evidence for assuming the location of Changokbyeong to be the frontal river terrace of Okbyeng seowon. The "Songgyun Jeoljo Suwol Jeongshin(松筠節調 水月精神)" rock inscription on Changokbyeong should be considered as the stamping ground and as the symbolic language of Changokbyeong that bears the high character and nobility of the Subject of Jouissance, Saahm Park Soon. The inscription should also be recognized as the handwritings of Wooahm Song Si-Yeol(尤庵 宋時烈) correcting the misconceptions that persisted until today. Meanwhile, the garden remains of Saahm's Changokbyeong are composed of four sites: Sangeumdae-Sugyeongdae-Cheonghakdae-Baekhakdae from the left. At the back of Sangeumdae, there is the original house, the Baegyeonwa(拜鵑窩), and on the fantastically shaped stone wall at the left of Baekhakdae, there is the annex, the Iyangjung, together creating a landscape composition that overlooks the splendor of the Ogari Stone Wall. The Iyangjung is located on the highest spot to the left of the four sites, and it is believed to have been a little outhouse and library for Saahm which remains to the present day as a place where Saahm's character can be felt. The drinking plates[窪樽] made of rock that are affectionately arranged on the broad flat rock in front of Iyangjung is part of the garden remains that reflects the artistic taste of Saahm regarding the drinking culture at the time.