• 대한인간공학회지
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• 제31권4호
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• pp.601-607
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• 2012

Objective: The aim of this study is to classify between intentional and natural blinks in vision based eye tracking system. Through implementing the classification method, we expect that the great eye tracking method will be designed which will perform well both navigation and selection interactions. Background: Currently, eye tracking is widely used in order to increase immersion and interest of user by supporting natural user interface. Even though conventional eye tracking system is well focused on navigation interaction by tracking pupil movement, there is no breakthrough selection interaction method. Method: To determine classification threshold between intentional and natural blinks, we performed experiment by capturing eye images including intentional and natural blinks from 12 subjects. By analyzing successive eye images, two features such as eye closed duration and pupil size variation after eye open were collected. Then, the classification threshold was determined by performing SVM(Support Vector Machine) training. Results: Experimental results showed that the average detection accuracy of intentional blinks was 97.4% in wearable eye tracking system environments. Also, the detecting accuracy in non-wearable camera environment was 92.9% on the basis of the above used SVM classifier. Conclusion: By combining two features using SVM, we could implement the accurate selection interaction method in vision based eye tracking system. Application: The results of this research might help to improve efficiency and usability of vision based eye tracking method by supporting reliable selection interaction scheme.

• 한국CDE학회논문집
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• 제16권4호
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• pp.277-284
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• 2011

In tangible augmented reality (AR) environments for virtual prototyping, the user interacts with virtual products by manipulating tangible objects with his or her hands, but the user often encounter awkward situations in which his or her hands are occluded by augmented virtual objects, which reduces both immersion and ease of interaction. In this paper, we present how to resolve such hand region occlusion in order to enhance natural interaction and immersive visualization. In the AR environment considered, we use two types (product-type and pointer-type) of tangible objects for tangible user interaction with a virtual product of interest. Holding the tangible objects with his or her hands, the user can create input events by touching specified regions of the product-type tangible object with the pointer-type tangible object. We developed a method for resolving hand region occlusion frequently arising during such user interaction, It first detect hand region in a real image and refines the rendered image of the virtual object by subtracting the hand region from the rendered image, Then, it superimposes the refined image onto the real image to obtain an image in which the occlusion is resolved. Incorporated into tangible AR interaction for virtual prototyping of handheld products such as cellular phones and MP3 players, the method has been found by a preliminary user study that it is not only useful to improve natural interaction and immersive visualization of virtual products, but also helpful for making the users experience the products' shapes and functions better.

• Bulletin of the Korean Chemical Society
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• 제6권1호
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• pp.23-29
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• 1985

The charge-transfer complexing properties of 1-methyl nicotinamide (MNA), an acceptor, and adenine, a donor, were investigated in water and SDS micellar solutions in relation to the intramolecular interaction in nicotinamide adenine dinucleotide ($NAD^+$). The spectral and thermodynamic parameters of MNA-indole and methyl viologen-adenine complex formations were determined, and the data were utilized to evaluate the charge-transfer abilities of MNA and adenine. The electron affinity of nicotinamide was estimated to be 0.28 eV from charge-transfer energy $of{\sim}300$ nm for MNA-indole. The large enhancement of MNA-indole complexation in SDS solutions by entropy effect was attributed to hydrophobic nature of indole. The complex between adenine and methyl viologen showed an absorption band peaked near 360 nm. The ionization potential of adenine was evaluated to be 8.28 eV from this. The much smaller enhancement of charge-transfer interaction involving adenine than that of indole in SDS solutions was attributed to weaker hydrophobic nature of the donor. The charge-transfer energy of 4.41 eV (280 nm) was estimated for nicotinamide-adenine complex. The spectral behaviors of $NAD^+$ were accounted to the presence of intramolecular interaction in $NAD^+$, which is only slightly enhanced in SDS solutions. The replacement of nicotinamide-adenine interaction in $NAD^+$ by intermolecular nicotinamide-indole interaction in enzyme bound $NAD^+$, and guiding role of adenine moiety in $NAD^+$ were discussed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권11호
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• pp.2966-2986
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• 2023

Climate change is a constant threat to human life, and it is important to understand the public perception of this issue. Previous studies examining climate change have been based on limited survey data. In this study, the authors used big data such as news articles and social media data, within which the authors selected specific keywords related to climate change. Using these natural language data, topic modeling was performed for discourse analysis regarding climate change based on various topics. In addition, before applying topic modeling, sentiment analysis was adjusted to discover the differences between discourses on climate change. Through this approach, discourses of positive and negative tendencies were classified. As a result, it was possible to identify the tendency of each document by extracting key words for the classified discourse. This study aims to prove that topic modeling is a useful methodology for exploring discourse on platforms with big data. Moreover, the reliability of the study was increased by performing topic modeling in consideration of objective indicators (i.e., coherence score, perplexity). Theoretically, based on the social amplification of risk framework (SARF), this study demonstrates that the diffusion of the agenda of climate change in public news media leads to personal anxiety and fear on social media.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2004년도 학술대회지
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• pp.139-142
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• 2004

The object of the present work is the acoustic emission energy analysis of subambient pressure tri-pad slider. Head/disk interaction during start/stop and constant speed were detected by using acoustic emission (AE) test system The frequency spectrum analysis is performed using the AE signal obtained during the head/disk interaction Natural frequency analysis was performed using Ansys program. Acoustic emission energy was calculated for the slider modes.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.117.3-117
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• 2001

This paper deals with a method for creating animation by interaction with animation operators. Operators are able to edit/transform any given motion data to more natural animations by the motion editing method proposed in this paper. The proposed technique is especially useful when some paris of character structure are changed. The system to be proposed is designed to fully utilize the experience of animation operators as well as to accomodate semi-automation process with spline interpolation. An example for retargeting a given motion data to a new character of dramatically changed kinematic structure.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1229-1232
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• 2014

• 한국전산구조공학회논문집
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• 제33권4호
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• pp.245-253
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• 2020

본 논문은 모노파일 풍력 지지구조물에 대한 공진 안전성 평가에서 여러 말뚝-구조물 상호작용(PSI) 모델을 사용하여 고유진동수를 비교하였다. PSI 재현을 위한 유한요소모델은 기저 스프링 모델, 분산 스프링 모델, 3차원 고체-쉘 모델을 사용하였다. PSI 모델이 고유주파수에 미치는 영향을 분석하기 위해 기저 스프링과 분산 스프링 모델 적용을 위한 강성행렬 산정법과 Winkler 보 모델을 각각 논문에 나타내고 이들 모델로부터 도출된 서로 다른 기하 및 지반조건을 갖는 모노파일의 고유진동수를 조사하였다. 해석결과는 또한 3차원 고체-쉘 모델의 고유진동수와도 비교되었다. 해석결과는 소구경 모노파일이 견고한 지반 및 암반에 관입된 경우 각 해석모델로부터 얻어진 고유진동수의 차이가 거의 없음을 보여준다. 반면 연약 지반에 설치된 대구경 모노파일에 대해 분산스프링 모델은 고유진동수를 과대평가할 수 있다. 따라서 고유진동수 평가 시 구조물 규모와 지반 조건을 고려해 적합한 PSI모델이 적용되어야 한다.

• Journal of Information Processing Systems
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• 제7권3호
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• pp.459-472
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• 2011

The vast number of biomedical literature is an important source of biomedical interaction information discovery. However, it is complicated to obtain interaction information from them because most of them are not easily readable by machine. In this paper, we present a method for extracting biomedical interaction information assuming that the biomedical Named Entities (NEs) are already identified. The proposed method labels all possible pairs of given biomedical NEs as INTERACTION or NO-INTERACTION by using a Maximum Entropy (ME) classifier. The features used for the classifier are obtained by applying various NLP techniques such as POS tagging, base phrase recognition, parsing and predicate-argument recognition. Especially, specific verb predicates (activate, inhibit, diminish and etc.) and their biomedical NE arguments are very useful features for identifying interactive NE pairs. Based on this, we devised a twostep method: 1) an interaction verb extraction step to find biomedically salient verbs, and 2) an argument relation identification step to generate partial predicate-argument structures between extracted interaction verbs and their NE arguments. In the experiments, we analyzed how much each applied NLP technique improves the performance. The proposed method can be completely improved by more than 2% compared to the baseline method. The use of external contextual features, which are obtained from outside of NEs, is crucial for the performance improvement. We also compare the performance of the proposed method against the co-occurrence-based and the rule-based methods. The result demonstrates that the proposed method considerably improves the performance.

• 소음진동
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• 제5권3호
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• pp.373-383
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• 1995

From the viewpoint of the structural design, the principal problem of the heat exchanger is the potentiality of structural instabilities due to the fluid loading effect during operations. Excessive fluid loading may give rise to permanent deformation of tube and would enentually result in collapse of heat exchanger, which would cause an obstruction of the fluid flow in the narrow channels. In this study, a fluid-structural interaction model was developed to investigate analtically the vibration characteristics of thin rectangular tube used in the heat exchanger. The model consists of two flat plates separated by fluid. The effects of the fluid in the tube was stuided. For analyses, the natural frequency coefficients of the model were investigated for the plate aspect ratios, channel heights, and boundary conditions. As conclusions, the natural frequency coefficients of the tube is found to be affected largely by the fluid loading and the channel heights.