• The Journal of the Convergence on Culture Technology
• /
• v.8 no.6
• /
• pp.953-958
• /
• 2022

Holographic Stereogram can provide the depth perception without the visual fatigue and dizziness because it use multiple images acquired from the multiple viewpoints. In order to produce a holographic stereogram, it is necessary to obtain perspective images of a live object and record it on film using a digital hologram printer. when acquiring perspective images, the hologram without distortion can be produced only when the perspective images with a constant distance between the camera and the target is obtained. If the target is small, it is possible to keep the constant distance from the camera to object. but if it is large, this is difficult to keep the constant distance. In this study, we photograph the large object using the POI (Point of Interest) function which is one of the smart flight modes of drone to produce perspective images required for the hologram production. after that, problems such as the unexpected shakings and distance change between camera and object is corrected in post production. as a result, we produce the perspective images.

• Journal of Convergence for Information Technology
• /
• v.12 no.3
• /
• pp.11-16
• /
• 2022

Although the number of foreign students is increasing with the development of internationalization, international students are often unfamiliar to the campus environment in the early stages of their school visits. This research aims to solve the problems of foreign students' unfamiliarity with the campus and the inconvenience of study and life after enrollment and to design and produce an AR campus guide application based on gamification. The application built are designed according to the targets, missions, and rewards of different places. Through the 'A Survey on the Awareness of Kongju University's Buildings' questionnaire survey of international students at National Kongju University, six place were selected as POI (Point of Interest). Missions and questions suitable for users were designed. Through this application, it is hoped that users can learn about important places of the school interestingly and learn about the use of related convenience facilities.

• The Journal of Korean Society for Radiation Therapy
• /
• v.21 no.1
• /
• pp.17-23
• /
• 2009

Purpose: In treating head and neck cancer, it is very important to irradiate uniform dose on the junction of the bilateral irradiation field of the upper head and neck and the anterior irradiation field of the lower neck. In order to improve dose distribution on the junction, this study attempted to correct non uniform dose resulting from under dose and over dose using the field-in-field technique in treating the anterior irradiation field of the lower neck and to apply the technique to the treatment of head and neck cancer through comparison with conventional treatment. Materials and Methods: In order to examine dose difference between the entry point and the exit point where beam diffusion happens in bilateral irradiation on the upper head and neck, we used an anthropomorphic phantom. Computer Tomography was applied to the anthropomorphic phantom, the dose of interest points was compared in radiation treatment planning, and it was corrected by calculating the dose ratio at the junction of the lower neck. Dose distribution on the junction of the irradiated field was determined by placing low-sensitivity film on the junction of the lower neck and measuring dose distribution on the conventional bilateral irradiation of the upper head and neck and on the anterior irradiation of the lower neck. In addition, using the field-in-field technique, which takes into account beam diffusion resulting from the bilateral irradiation of the upper head and neck, we measured difference in dose distribution on the junction in the anterior irradiation of the lower neck. In order to examine the dose at interest points on the junction, we compared and analyzed the change of dose at the interest points on the anthropomorphic phantom using a thermoluminescence dosimeter. Results: In case of dose sum with the bilateral irradiation of the upper head and neck when the field-in-field technique is applied to the junction of the lower neck in radiation treatment planning, The dose of under dose areas increased by 4.7~8.65%. The dose of over dose areas also decreased by 2.75~10.45%. Moreover, in the measurement using low-sensitivity film, the dose of under dose areas increased by 11.3%, and that of over dose areas decreased by 5.3%. In the measurement of interest point dose using a thermoluminescence dosimeter, the application of the field-in-field technique corrected under dose by minimum 7.5% and maximum 17.6%. Thus, with the technique, we could improve non.uniform dose distribution. Conclusion: By applying the field-in-field technique, which takes into account beam divergence in radiation treatment planning, we could reduce cold spots and hot spots through the correction of dose on the junction and, in particular, we could correct under dose at the entry point resulting from beam divergence. This study suggests that the clinical application of the field-in-field technique may reduce the risk of lymph node metastasis caused by under dose on the cervical lymph node.

• Journal of Korea Multimedia Society
• /
• v.14 no.10
• /
• pp.1229-1237
• /
• 2011

The volume ray-casting method is one of the direct volume rendering methods that produces high-quality images as well as manipulates semi-transparent object. Although the volume ray-casting method produces high-quality image by sampling in the region of interest, its rendering speed is slow since the color acquisition process is complicated for repetitive memory reference and accumulation of sample values. Recently, the GPU-based acceleration techniques are introduced. However, they require pre-processing or additional memory. In this paper, we propose efficient point-primitive based method to overcome complicated computation of GPU ray-casting. It presents semi-transparent objects, however it does not require preprocessing and additional memory. Our method is fast since it generates point-primitives from volume dataset during sampling process and it projects the primitives onto the image plane. Also, our method can easily cope with OTF change because we can add or delete point-primitive in real-time.

• Journal of the Korean Society for Precision Engineering
• /
• v.23 no.5 s.182
• /
• pp.143-148
• /
• 2006

It is still very difficult to generate a geometry model and finite element model, which has complex and many free surface, even though 3D CAD solutions are applied. Furthermore, in the medical field, which is a big growth area of recent years, there is no drawing. For these reasons, making a geometry model, which is used in finite element analysis, is very difficult. To resolve these problems and satisfy the requests of the need to create a 3D digital file for an object where none had existed before, new technologies are appeared recently. Among the recent technologies, there is a growing interest in the availability of fast, affordable optical range laser scanning. The development of 3D laser scan technology to obtain 3D point cloud data, made it possible to generate 3D model of complex object. To generate CAD and finite element model using point cloud data from 3D scanning, surface reconstruction applications have widely used. In the early stage, these applications have many difficulties, such as data handling, model creation time and so on. Recently developed point-based surface generation applications partly resolve these difficulties. However there are still many problems. In case of large and complex object scanning, generation of CAD and finite element model has a significant amount of working time and effort. Hence, we concerned developing a good direct finite element model generation method using point cloud's location coordinate value to save working time and obtain accurate finite element model.

• The Journal of Korean Academy of Prosthodontics
• /
• v.24 no.1
• /
• pp.45-54
• /
• 1986

The establishment and/or registration of an optimal or physiologic relationship between the maxillae and mandible has long been a subject of considerable interest and controversy in dentistry. Centric relation has been generally accepted as a repeatable starting point for restoring the mouth. Recently, it has been claimed that an electronic device (Myo-Monitor) will produce an accurate, reproducible occlusal registration at the vertical and horizontal occlusal position most compatible with the muscular of each patient. The objectives of this study was to compare Myo-Monitor centric to centric relation at the points of reproducibility and anteroposterior, superoinferior position. A Vericheck instrument was employed for examining difference in the position and reproducibility of mandible reproduced by the various check bite records. For this study, 8 dental students and dentists who had no missing teeth and no difficulties of mandibular movement were selected. The following three different positions of the mandible were registered (a) centric relation manipulated by means of chin-point technique with Lucia-jig, (b) centric relation manipulated by means of bilateral technique, (c) Myocentric manipulated by Myo-Monitor. From this experiment, the following results were obtained. 1. Bilateral manipulated centric relation was more reproducible than Myocentric in anteroposterior and superoinferior position , but more reproducible than centric relation manipulated by means of chin point technique with Lucia-jig in anteroposoterior position. Centric relation manipulated by means of chin Point technique with Lucia-jig was more reproducible than Myocentric in right anteroposterior and superoinferior position. 2. Centric relation by means of chin point technique with Lucia-jig was posterior($2.16{\pm}0.78mm$) and superior($0.41{\pm}0.16mm$) to centric occlusion. Bilateral manipulated centric relation was posterior($1.68{\pm}0.10mm$) and superior($1.02{\pm}0.45mm$) to centric occlusion. Myocentric was anterior($0.75{\pm}0.70mm$), inferior($0.59{\pm}0.44mm$) to centric occlusion.

• Journal of Advanced Navigation Technology
• /
• v.27 no.4
• /
• pp.481-487
• /
• 2023

Recently, interest in UAM (Urban Air Mobility) has surged as a critical solution to urban traffic congestion and air pollution issues. However, efficient UAM operation requires accurate 3D Point Cloud data processing, particularly in separating the ground and objects. This paper proposes and validates a method for effectively separating ground and objects in a UAM environment, taking into account its dynamic and complex characteristics. Our approach combines attitude information from MEMS sensors with ground plane estimation using RANSAC, allowing for ground/object separation that isless affected by GPS errors. Simulation results demonstrate that this method effectively operates in UAM settings, marking a significant step toward enhancing safety and efficiency in urban air mobility. Future research will focus on improving the accuracy of this algorithm, evaluating its performance in various UAM scenarios, and proceeding with actual drone tests.

• Journal of Venture Innovation
• /
• v.5 no.3
• /
• pp.71-80
• /
• 2022

The real estate market is an important part of a country's economy and plays a major role in economic growth through the growth of many related industries. Changes in interest rates affect asset prices and have a significant impact on housing prices. This study analyzed housing prices by dividing them into nationwide, local, and Seoul housing prices in order to analyze whether the effect of changes in interest rates on housing prices shows regional differences. The analysis was conducted from the first quarter of 2011 to the fourth quarter of 2021, and was analyzed using the DOLS model. The main analysis results are as follows. First, interest rates were found to have a significant negative effect on national housing prices, and a drop in interest rates significantly increased national housing prices and an increase in interest rates significantly lowered national housing prices. The consumer price index and loan growth rate also had a positive effect on housing prices nationwide, but statistical significance was not high. Second, interest rates had a negative effect on local housing prices, unlike national housing prices, but were not statistically significant. On the other hand, it was found that the consumer price index and loan growth rate had a larger and significant positive effect on local housing prices compared to national housing prices. Finally, it was found that the interest rate had the only significant negative effect on housing prices in Seoul. And this effect was greater and more significant than the effect on national and local housing prices. In the end, it was found that the effect of interest rates on Korean housing prices differs locally. Interest rates have a significant negative effect on national housing prices, and local housing prices, but they are not statistically significant. In addition, the interest rate was found to have the largest and most significant negative effect on housing prices in Seoul. In addition, it was found that there was a difference in the effect of macroeconomic variables on housing prices. This means that there are differences between regions with different factors influencing local and Seoul housing prices, and this point should be considered when drafting and implementing real estate policies.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.3
• /
• pp.1009-1014
• /
• 2012

The influence of magnetic fields on chemical processes has long been the subject of interest to researchers. For this time numerous investigations show that commonly the effect of a magnetic field on chemical reactions is insignificant with impact less than 10 percent. However, there are some papers that point to the observation of external magnetic field effect on chemical and biochemical systems actually having a significant impact on the reactions. Thus, of great interest is an active search for rather simple but realistic models, that are based on physically explicit assumptions and able to account for a strong effect of low magnetic fields. The present work theoretically deals with two models explaining how an applied weak magnetic field might influence the steady state of a non-equilibrium chemical system. It is assumed that external magnetic field can have effect on the rates of radical reactions occurring in a system. This, in turn, leads to bifurcation of the nonequilibrium stationary state and, thus, to a drastic change in the properties of chemical systems (temperature and reagent concentration).

• International Commerce and Information Review
• /
• v.12 no.2
• /
• pp.409-438
• /
• 2010

According to Sun Tzu's Art of War, "if you know yourself and your enemy you win hundred battles out of a hundred." This is also apply for international business field. International business negotiation will not be failed if you know counter party's behavior and understand their culture and customs. The cooperative approach is known as interest-based negotiation. Interest-based negotiation is particularly effective in a global business characterized by diversity. We often need to reach agreement with people who are different from us - culturally, ethnically, or economically. If we cannot get beyond the differences, they can create obstacles to agreement. To do this, we need to focus on the interests of the parties instead of on the parties' differences. Every culture has their own distinctive feature that the people from outside seems not understand but they must have the optimistic attitude which complies with. The purpose of this paper, from the point of view above, is to examine cultural differences that could make sure comparative advantage in business negotiation of the enterprises who eager to expand their market or to invest internationally. This paper especially shows cultural deferences among Korea, China and Japan in terms of business we must consider.