• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.1-6
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• 2019

As mobile technologies such as Internet of Things (IoT)-based smart homes and financial technologies (FinTech) are developed, authentication by smart devices is used everywhere. As a result, presence-based biometric authentication using smart devices has become a new mainstream in knowledge-based authentication methods like the existing passwords. The electrocardiogram (ECG) is less prone to forgery, and high-level personal identification is its unique feature from among various biometric authentication methods, such as the pulse, fingerprints, the face, and the iris. Biometric authentication using an ECG is receiving a great deal of attention due to its uses in healthcare and FinTech. In this study, we implemented an ECG authentication system that allows users to easily measure and authenticate their ECG waveforms using a miniaturized wearable device, rather than a large and expensive measurement device. The implemented ECG authentication system identifies ECG features through P-Q-R-S-T feature point identification, and was user-certified under the proposed authentication protocols. Finally, assessment of measurements in a majority of adult males showed a relatively low false acceptance rate of 1.73%, and a low false rejection rate of 4.14%, in a stable normal state. In a high-activity state, the false acceptance rate was 13.72%, and the false rejection rate was 21.68%. In a high-heart rate state, the false acceptance rate was 10.48%, and the false rejection rate was 11.21%.

• Journal of Digital Convergence
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• v.17 no.6
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• pp.373-380
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• 2019

In this study, I examined the visual elements for narrative structure and the symbols, scene components and visual styles in the images through analyze the flat staging in Tomm Moore's animated feature film, . As a research method, I figure out the general theories about staging and analyze extracted scenes which revealed flat staging in the , then summarize and clarify the flat staging production elements and features of Tomm Moore. As a result, in , the composition of the screen using the basic shapes, the screen composition containing the spiral which is symbol of the Celtic traditional pattern, the stable and flat frame expression through the balanced screen composition, expression of spatial sensation using perspective, appearance of the period by using the inverted perspective, and composition that can emphasize the flat formability are appeared as a characteristic. Through this, the two-dimensional planarity was maximized to convey the feeling of appreciating the illustrations of fairy tales. Tomm Moore, who produced animation based on folk tales in order to inherit the traditional culture of Ireland, has been attracting worldwide attention because of its flat staging to help narrative, enhancing the original expression and performance of animation. I hope that this study will be used as basic data for industry workers and researchers who make unique and excellent animated feature film.

• The Journal of the Korea Contents Association
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• v.22 no.2
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• pp.10-21
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• 2022

In order to improve formal presentation attitudes such as presentation of job interviews and presentation of project results at the company, there are few automated methods other than observation by colleagues or professors. In previous studies, it was reported that the speaker's stable speech and gaze processing affect the delivery power in the presentation. Also, there are studies that show that proper feedback on one's presentation has the effect of increasing the presenter's ability to present. In this paper, considering the positive aspects of correction, we developed a program that intelligently corrects the wrong presentation habits and attitudes of college students through facial analysis of videos and analyzed the proposed program's performance. The proposed program was developed through web-based verification of the use of redundant words and facial recognition and textualization of the presentation contents. To this end, an artificial intelligence model for classification was developed, and after extracting the video object, facial feature points were recognized based on the coordinates. Then, using 4000 facial data, the performance of the algorithm in this paper was compared and analyzed with the case of facial recognition using a Teachable Machine. Use the program to help presenters by correcting their presentation attitude.

• Journal of Cadastre & Land InformatiX
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• v.53 no.1
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• pp.47-63
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• 2023

The Seoul Metropolitan Government is building and operating digital twin-based urban spatial information to solve various problems in the city and provide public services. Two essential factors to ensure the stable utilization of spatial information for the implementation of such a digital twin city are the latest and quality of the data. However, it is time-consuming and costly to maintain continuous updating of high-quality urban spatial information. To overcome this problem, we studied efficient urban spatial information construction technology and the operation, management, and update procedures of construction data. First, we demonstrated and applied automatic 3D building construction technology centered on point clouds using the latest hybrid sensors, confirmed that it is possible to automatically construct high-quality building models using high-density airborne lidar results, and established an efficient data management plan. By applying differentiated production methods by region, supporting detection of urban change areas through Seoul spatial feature identifiers, and producing international standard data by level, we strengthened the utilization of urban spatial information. We believe that this study can serve as a good precedent for local governments and related organizations that are considering activating urban spatial information based on digital twins, and we expect that discussions on the construction and management of spatial information as infrastructure information for city-level digital twin implementation will continue.

• The Transactions of the Korea Information Processing Society
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• v.13 no.4
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• pp.199-207
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• 2024

Local reservoirs are crucial sources for agricultural water supply, necessitating stable water level management to prepare for extreme climate conditions such as droughts. Water level prediction is significantly influenced by local climate characteristics, such as localized rainfall, as well as seasonal factors including cropping times, making it essential to understand the correlation between input and output data as much as selecting an appropriate prediction model. In this study, extensive multivariate data from over 400 reservoirs in Jeollabuk-do from 1991 to 2022 was utilized to train and validate a water level prediction model that comprehensively reflects the complex hydrological and climatological environmental factors of each reservoir, and to analyze the impact of each input feature on the prediction performance of water levels. Instead of focusing on improvements in water level performance through neural network structures, the study adopts a basic Feedforward Neural Network composed of fully connected layers, batch normalization, dropout, and activation functions, focusing on the correlation between multivariate input data and prediction performance. Additionally, most existing studies only present short-term prediction performance on a daily basis, which is not suitable for practical environments that require medium to long-term predictions, such as 10 days or a month. Therefore, this study measured the water level prediction performance up to one month ahead through a recursive method that uses daily prediction values as the next input. The experiment identified performance changes according to the prediction period and analyzed the impact of each input feature on the overall performance based on an Ablation study.

• Journal of KIISE:Computer Systems and Theory
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• v.31 no.3_4
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• pp.224-238
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• 2004

Multi-modality image registration is a widely used image processing technique to obtain composite information from two different kinds of image sources. This study proposes an image registration method based on moment information and surface distance, which improves the previous surface-based registration method. The proposed method ensures stable registration results with low registration error without being subject to the initial position and direction of the object. In the preprocessing step, the surface points of the object are extracted, and then moment information is computed based on the surface points. Moment information is matched prior to fine registration based on the surface distance, in order to ensure stable registration results even when the initial positions and directions of the objects are very different. Moreover, surface comer sampling algorithm has been used in extracting representative surface points of the image to overcome the limits of the existed random sampling or systematic sampling methods. The proposed method has been applied to brain MRI(Magnetic Resonance Imaging) and PET(Positron Emission Tomography), and its accuracy and stability were verified through registration error ratio and visual inspection of the 2D/3D registration result images.

• Journal of Navigation and Port Research
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• v.44 no.4
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• pp.275-282
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• 2020

Recently, the occurrence of a ship capsizing was analyzed as the main cause of the lack of stability or loss because of the improper management of the center of gravity, the movement of cargo or heavy weight when excessive steering occurs or when navigating during bad weather. Thus, to prevent a ship from capsizing, it is necessary to secure stability to enable the ship's return to its upright position, even if a dangerous heel occurs. The GM is a crucial evaluation factor regarding stability, which the navigation officer uses to preserve stability. In this study, based on the stability data collected from the operating of ships for five years, The GM by ship's type according to the operating status was analyzed specifically such as a ship's length, breadth, and gross tonnage. The feature of the GM distribution according to a ship's length was confirmed, and after performing the correlation analysis between the breadth and the GM, the ratio of the GM to breadth was calculated, and the result was compared with the previous ratio. Additionally, a simple approximation formula and minimum GM for the estimation of the GM by ship type were proposed by the regression analysis of the GM using the gross tonnage (GT)/breadth (B) to reflect the trend of larger ships being built. The results of this study are expected to be used as data for the review of securing a stable GM on ships.

• Korean Journal of Environmental Biology
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• v.25 no.1
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• pp.56-65
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• 2007

The aim of this study is to provide a fundamental data which can be applied to management conservation, and restoration of coastal sand dune vegetation by determining the classification and distribution of community, and ecological characteristics of the habitat. This research was performed by the Braun-Blanquet's method. The coastal sand dune vegetation of Uido (I.) was composed with 9 communities as follows : Vitex rotundifolia community, Zoysia macrostachya community, Carex kobomugi community, Iachaemum anthephoroides community, Imperata cylindrica var. koenigii community, Carex pumila community, Calystegia soldanella community Messerschmidia sibirica community and Pinus thunbergii community, the evergreen needle-leaved forest. The constancy degree showed high in Calystegia soldanella (77%), Vitex rotundifolia (74%), Carex kobomugi (66%), Zoysia macrostachya (50%) and Imperata cylindrica var. koenigii (47%). However the highest constancy degree Calystegia soldanella has, it turned out to have low net contribution degree (NCD) in each community. In terms of the distribution and growth feature of the composition species in the coastal sand dune, Vitex rotundifolia, Carex kobomuri and Zoysia macrostachya were widely distributed from unstable sand dune to stable one but Iachaemum anthephoroides and Imperata cylindrica var. koenigii were mainly found at the stable sand dune. Carex kobomugi was especially dominant at the unstable sand dune where the sand continued to be deposited. On the other hand, Carer pumila and Messerschmidia sibirica showed regional distributions around fresh water.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.12
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• pp.1301-1307
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• 2011

Electrosurgical knee wand (EKW) is a high-frequency thermocautery instrument and is often used for coagulation, ablation, excision, and extirpation of knee ligaments and tissues. In order to maximize the success rate, ease, and safety of knee surgery using EKW and radiofrequency ablation, it is necessary to ensure that the EKW selectively approaches the lesion with utmost accuracy and safety. The key feature of this instrument is its excellent maneuverability. Hence, the authors constructed a tensile spring model based on a shape memory alloy (SMA), which exhibits the shape memory effect. This model can be used in knee surgery as it is considered the most biocompatible femorotibial surgical actuator. The changes in external temperature with current and the thermoelectric characteristics of the SMA were investigated. The relationship between the restoring force and the typical stroke (TS) in response to the conditions in the SMA tensile spring design were evaluated. In conclusion, as the diameter of the SMA tensile spring decreased, the maximum temperature increased. The strain in the actuator caused a stable and proportional increase in the force and induced current for up to 15s, but this increase became very unstable after 30s. Moreover, the relationship between the current and the TS was more stable than that between the current and the restoring force.

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.557-564
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• 1996

Based on stem analysis as well as branch analysis data of each tree from 8 plots of circle clear-cutting and 1 biomass plot in Changbai Mountain area, located in Northeast of China, the effective crown form of Changbai larch(Larix olgensis H.) plantation were studied by using the approach of crown curve. The results indicated that the cross-section forms of effective crown were stable and showed approximate circle for different tree size. Because the effective crown was on upper position of the canopy and its form reflects crown architecture under non-competition condition, the architecture is mainly affected by species hereditary feature. Therefore, for the specified species the effective crown form was thought to be relatively stable. The effective crown form of tree was neither related to the tree size within stand nor to the stand condition for different stand. The total effective crown curve of larch plantation could be characterized by using mean effective crown taper.