• Journal of information and communication convergence engineering
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• 제2권3호
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• pp.172-176
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• 2004

In special effects industry there is a high demand to convincingly mimic the appearance and behavior of natural phenomena such as smoke, waterfall, rain, and fire. Particle systems are methods adequate for modeling fuzzy objects of natural phenomena. This paper presents particle system graphics library for generating special effects in video games and virtual reality applications. The library is a set of functions that allow c++ programs to simulate the dynamics of particles for special effects in interactive and non-interactive graphics applications, not for scientific simulation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.191-194
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• 2005

Over the past decade, changes in product development processes and increased consumer demands have dramatically influenced engineering working practices and targets. The information technology revolution has made its appearance concurrent to this relentless escalation in product engineering requirement. It has offered hopes for improved productivity despite these increasing demands. The wide availability of personal computing power, virtually inexhaustible sources of information and an abundance of computerized engineering tools have created great expectations. Knowledge information modeling system and database were developed using ASP and Microsoft SQL 2000 Server to share the DB that can be utilized to process on the web.

• International Journal of Contents
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• 제2권2호
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• pp.1-5
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• 2006

The modeling and animation of natural phenomena have received much attention from the computer graphics community. Synthetic of natural phenomena are required for such diverse applications as flight simulators, special effects, video games and other virtual realty. In special effects industry there is a high demand to convincingly mimic the appearance and behavior of natural phenomena such as smoke, waterfall, rain, and fire. Particle systems are methods adequate for modeling fuzzy objects of natural phenomena. This paper presents particle system API(Application Program Interfaces) for generating special effects in virtual reality applications. The API are a set of functions that allow C++ programs to simulate the dynamics of particles for special effects in interactive and non-interactive graphics applications, not for scientific simulation.

• Journal of International Society for Simulation Surgery
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• 제2권1호
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• pp.7-9
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• 2015

Purpose In the many face-related application such as head pose estimation, 3D face modeling, facial appearance manipulation, the robust and fast facial feature extraction is necessary. We present the facial feature extraction method based on shape regression and feature selection for real-time facial feature extraction. Materials and Methods The facial features are initialized by statistical shape model and then the shape of facial features are deformed iteratively according to the texture pattern which is selected on the feature pool. Results We obtain fast and robust facial feature extraction result with error less than 4% and processing time less than 12 ms. The alignment error is measured by average of ratio of pixel difference to inter-ocular distance. Conclusion The accuracy and processing time of the method is enough to apply facial feature based application and can be used on the face beautification or 3D face modeling.

• Archives of Plastic Surgery
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• 제50권4호
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• pp.335-339
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• 2023

It is undeniable that a significant number of patients who want to improve their facial appearance is increasingly interested in nonsurgical procedures. Without a doubt, the use of autologous fat could not be left out as a magnificent alternative for nasal modeling simply because of four influential factors: ease of collection, compatibility, the temporality of the results, and safety. This work describes an innovative alternative technique for nasal modeling using micrografts enriched with adipose-derived mesenchymal stem cells (ASCs). With this technique, fat was collected and divided into two samples, nanofat and microfat. Nanofat was used to isolate the ASCs; microfat was enriched with ASCs and used for nasal modeling. Lipoinjection was performed in a supraperiosteal plane on the nasal dorsum. Through a retrolabial access, the nasal tip and base of the columella were lipoinjected. We consider that nonsurgical nasal modeling using micrografts enriched with ASCs can be an attractive and innovative alternative. This technique will never be a substitute for surgical rhinoplasty. It can be performed in a minor procedure area with rapid recovery and return to the patient's daily activities the next day. If necessary, the procedure can be repeated.

• 디지털융복합연구
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• 제11권8호
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• pp.205-212
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• 2013

본 논문에서는 한국의 전통 돌담을 생성하는 프랙탈을 이용한 절차적 모델링 알고리즘을 제시한다. 각 단계의 삼각형 메쉬를 세분하여 다음 단계의 메쉬를 얻는 것이 알고리즘의 주요 내용이다. 메쉬의 세분화 과정은 원하는 단계까지 재귀적으로 적용된다. 삼각형의 각 변에서 세 점을 무작위로 선택하여 네 작은 삼각형으로 나눈 후 각 정점이 법벡터 방향으로 조금씩 이동하면서 돌담의 울퉁불퉁한 모양을 만들어낸다. 매 단계마다 세분화한 메쉬에서 모양에 변화를 주지 않는 평평한 정점을 제거한다. 평평한 정도는 이산 곡률로 측정한다. 제거된 정점 주변의 점들로부터 새로운 삼각형들을 만들어 삼각형 메쉬를 완성한다.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제10권2호
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• pp.53-66
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• 2006

최근 몰입도가 높은 가시화 기법 중 하나인 3차원 입체영상에 관심이 높아지고 있다. 그러나 일반적인 2차원 영상과는 달리 3차원 입체 영상은 3차원의 기하정보가 존재해야만 영상 생성이 가능하다. 3차원 기하정보가 존재하지 않는 2차원 영상을 이용한 입체 영상 저작이 매우 어렵다. 따라서 본 논문에서는 영상 기반 모델링 기법을 이용한 한 장의 실사 영상으로부터 3차원 입체 영상 생성하기 위한 3차원 입체 영상 저작 시스템을 제안한다. 제안한 시스템은 Adobe Photoshop(R)의 Plug-in형태로 개발함으로써 범용성과 확장성을 고려하였고 몰입감이 높은 입체 영상의 시점을 결정하기 위한 대화식 3차원 입체 영상 미리 보기 기능을 제공한다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제2권1호
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• pp.53-58
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• 2002

In the construction of successful fuzzy models for nonlinear systems, the identification of an optimal fuzzy model system is an important and difficult problem. Traditionally, sGA(simple genetic algorithm) has been used to identify structures and parameters of fuzzy model because it has the ability to search the optimal solution somewhat globally. But SGA optimization process may be the reason of the premature local convergence when the appearance of the superior individual at the population evolution. Therefore, in this paper we propose a new method that can yield a successful fuzzy model using VmGA(virus messy genetic algorithms). The proposed method not only can be the countermeasure of premature convergence through the local information changed in population, but also has more effective and adaptive structure with respect to using changeable length string. In order to demonstrate the superiority and generality of the fuzzy modeling using VmGA, we finally applied the proposed fuzzy modeling methodof a complex nonlinear system.

• Journal of Preventive Medicine and Public Health
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• 제52권6호
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• pp.384-392
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• 2019

Objectives: This study aimed to explore the health inequality discourse in the Korean press by analyzing newspaper articles using a relatively new content analysis technique. Methods: This study used the search term "health inequality" to collect articles containing that term that were published between 2000 and 2018. The collected articles went through pre-processing and topic modeling, and the contents and temporal trends of the extracted topics were analyzed. Results: A total of 1038 articles were identified, and 5 topics were extracted. As the number of studies on health inequality has increased over the past 2 decades, so too has the number of news articles regarding health inequality. The extracted topics were public health policies, social inequalities in health, inequality as a social problem, healthcare policies, and regional health gaps. The total number of occurrences of each topic increased every year, and the trend observed for each theme was influenced by events related to its contents, such as elections. Finally, the frequency of appearance of each topic differed depending on the type of news source. Conclusions: The results of this study can be used as preliminary data for future attempts to address health inequality in Korea. To make addressing health inequality part of the public agenda, the media's perspective and discourse regarding health inequality should be monitored to facilitate further strategic action.

• 정보관리학회지
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• 제39권4호
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• pp.23-48
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• 2022

본 연구는 키워드 네트워크 분석과 토픽모델링을 활용하여 국내 정보활용교육 연구의 흐름을 살펴보고 향후 정보활용교육의 방향성을 모색하는데 목적이 있다. 이를 위하여 국내 문헌정보학 분야의 학술지에 게재된 정보활용교육과 관련된 논문 306편을 선정하고, 논문의 초록을 대상으로 전처리 과정을 거쳐 전체 키워드 출현 빈도, 시기별 키워드 출현 빈도, 키워드 동시출현 빈도분석을 수행하였다. 이어서 키워드 네트워크 분석을 통해 키워드의 연결중심성과 매개중심성, 위세중심성을 분석하였다. 또한 구조적 토픽모델링 분석을 활용하여 15개의 토픽(교육과정, 정보활용교육 효과, 정보활용교육 내용, 학교도서관 교육, 정보매체활용, 정보활용능력 평가 지표, 도서관 불안, 공공도서관 프로그램, 대학도서관 이용자교육, 건강정보 활용능력, 정보격차, 도서관활 용수업 개선, 연구 동향, 정보활용교육 모델, 교사 역할)을 도출하고, 토픽별로 비중의 변화를 확인하기 위해 연도별 토픽 추이를 분석하였다. 이러한 결과를 바탕으로 정보활용교육의 방향성과 후속 연구에 대한 제언을 제시하였다.