• Title/Summary/Keyword: Feature-based Method

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Mobile Robot Localization and Mapping using Scale-Invariant Features (스케일 불변 특징을 이용한 이동 로봇의 위치 추정 및 매핑)

  • Lee, Jong-Shill;Shen, Dong-Fan;Kwon, Oh-Sang;Lee, Eung-Hyuk;Hong, Seung-Hong
    • Journal of IKEEE
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    • v.9 no.1 s.16
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    • pp.7-18
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    • 2005
  • A key component of an autonomous mobile robot is to localize itself accurately and build a map of the environment simultaneously. In this paper, we propose a vision-based mobile robot localization and mapping algorithm using scale-invariant features. A camera with fisheye lens facing toward to ceiling is attached to the robot to acquire high-level features with scale invariance. These features are used in map building and localization process. As pre-processing, input images from fisheye lens are calibrated to remove radial distortion then labeling and convex hull techniques are used to segment ceiling region from wall region. At initial map building process, features are calculated for segmented regions and stored in map database. Features are continuously calculated from sequential input images and matched against existing map until map building process is finished. If features are not matched, they are added to the existing map. Localization is done simultaneously with feature matching at map building process. Localization. is performed when features are matched with existing map and map building database is updated at same time. The proposed method can perform a map building in 2 minutes on $50m^2$ area. The positioning accuracy is ${\pm}13cm$, the average error on robot angle with the positioning is ${\pm}3$ degree.

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A System of Audio Data Analysis and Masking Personal Information Using Audio Partitioning and Artificial Intelligence API (오디오 데이터 내 개인 신상 정보 검출과 마스킹을 위한 인공지능 API의 활용 및 음성 분할 방법의 연구)

  • Kim, TaeYoung;Hong, Ji Won;Kim, Do Hee;Kim, Hyung-Jong
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.5
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    • pp.895-907
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    • 2020
  • With the recent increasing influence of multimedia content other than the text-based content, services that help to process information in content brings us great convenience. These services' representative features are searching and masking the sensitive data. It is not difficult to find the solutions that provide searching and masking function for text information and image. However, even though we recognize the necessity of the technology for searching and masking a part of the audio data, it is not easy to find the solution because of the difficulty of the technology. In this study, we propose web application that provides searching and masking functions for audio data using audio partitioning method. While we are achieving the research goal, we evaluated several speech to text conversion APIs to choose a proper API for our purpose and developed regular expressions for searching sensitive information. Lastly we evaluated the accuracy of the developed searching and masking feature. The contribution of this work is in design and implementation of searching and masking a sensitive information from the audio data by the various functionality proving experiments.

Hierarchical Visualization of the Space of Facial Expressions (얼굴 표정공간의 계층적 가시화)

  • Kim Sung-Ho;Jung Moon-Ryul
    • Journal of KIISE:Computer Systems and Theory
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    • v.31 no.12
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    • pp.726-734
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    • 2004
  • This paper presents a facial animation method that enables the user to select a sequence of facial frames from the facial expression space, whose level of details the user can select hierarchically Our system creates the facial expression space from about 2400 captured facial frames. To represent the state of each expression, we use the distance matrix that represents the distance between pairs of feature points on the face. The shortest trajectories are found by dynamic programming. The space of facial expressions is multidimensional. To navigate this space, we visualize the space of expressions in 2D space by using the multidimensional scaling(MDS). But because there are too many facial expressions to select from, the user faces difficulty in navigating the space. So, we visualize the space hierarchically. To partition the space into a hierarchy of subspaces, we use fuzzy clustering. In the beginning, the system creates about 10 clusters from the space of 2400 facial expressions. Every tine the level increases, the system doubles the number of clusters. The cluster centers are displayed on 2D screen and are used as candidate key frames for key frame animation. The user selects new key frames along the navigation path of the previous level. At the maximum level, the user completes key frame specification. We let animators use the system to create example animations, and evaluate the system based on the results.

Effect of SPR Chip with Nano-structured Surface on Sensitivity in SPR Sensor (나노형상을 가진 표면플라즈몬공명 센서칩의 감도 개선 효과)

  • Cho, Yong-Jin;Kim, Chul-Jin;Kim, Namsoo;Kim, Chong-Tai;Kim, Tae-Eun;Kim, Hyo-Sop;Kim, Jae-Ho
    • Food Engineering Progress
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    • v.14 no.1
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    • pp.49-53
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    • 2010
  • Surface plasmon resonance (SPR) which is utilized in thin film refractometry-based sensors has been concerned on measurement of physical, chemical and biological quantities because of its high sensitivity and label-free feature. In this paper, an application of SPR to detection of alcohol content in wine and liquor was investigated. The result showed that SPR sensor had high potential to evaluate alcohol content. Nevertheless, food industry may need SPR sensor with higher sensitivity. Herein, we introduced a nano-technique into fabrication of SPR chip to enhance SPR sensitivity. Using Langmuir-Blodgett (LB) method, gold film with nano-structured surface was devised. In order to make a new SPR chip, firstly, a single layer of nano-scaled silica particles adhered to plain surface of gold film. Thereafter, gold was deposited on the template by an e-beam evaporator. Finally, the nano-structured surface with basin-like shape was obtained after removing the silica particles by sonication. In this study, two types of silica particles, or 130 nm and 300 nm, were used as template beads and sensitivity of the new SPR chip was tested with ethanol solution, respectively. Applying the new developed SPR sensor to a model food of alcoholic beverage, the sensitivity showed improvement of 95% over the conventional one.

High Voltage β-Ga2O3 Power Metal-Oxide-Semiconductor Field-Effect Transistors (고전압 β-산화갈륨(β-Ga2O3) 전력 MOSFETs)

  • Mun, Jae-Kyoung;Cho, Kyujun;Chang, Woojin;Lee, Hyungseok;Bae, Sungbum;Kim, Jeongjin;Sung, Hokun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.32 no.3
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    • pp.201-206
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    • 2019
  • This report constitutes the first demonstration in Korea of single-crystal lateral gallium oxide ($Ga_2O_3$) as a metal-oxide-semiconductor field-effect-transistor (MOSFET), with a breakdown voltage in excess of 480 V. A Si-doped channel layer was grown on a Fe-doped semi-insulating ${\beta}-Ga_2O_3$ (010) substrate by molecular beam epitaxy. The single-crystal substrate was grown by the edge-defined film-fed growth method and wafered to a size of $10{\times}15mm^2$. Although we fabricated several types of power devices using the same process, we only report the characterization of a finger-type MOSFET with a gate length ($L_g$) of $2{\mu}m$ and a gate-drain spacing ($L_{gd}$) of $5{\mu}m$. The MOSFET showed a favorable drain current modulation according to the gate voltage swing. A complete drain current pinch-off feature was also obtained for $V_{gs}<-6V$, and the three-terminal off-state breakdown voltage was over 482 V in a $L_{gd}=5{\mu}m$ device measured in Fluorinert ambient at $V_{gs}=-10V$. A low drain leakage current of 4.7 nA at the off-state led to a high on/off drain current ratio of approximately $5.3{\times}10^5$. These device characteristics indicate the promising potential of $Ga_2O_3$-based electrical devices for next-generation high-power device applications, such as electrical autonomous vehicles, railroads, photovoltaics, renewable energy, and industry.

A Study on the Visibility Ratio Analysis Technique for Establishing the Cultural Property Protective Zone (문화재 보호구역 설정을 위한 가시율 분석 기법에 관한 연구)

  • Park, Eun-Hee;Kim, Tae-Han;Lee, Jae-Keun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.2
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    • pp.108-117
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    • 2011
  • In drafting the standards on changes in current conditions, the height or the number of stories is applied in a restrictive manner by limiting to securing the distance to vertical surface for cultural properties within the influence investigation area, but this is expected to have a negative impact on the surrounding sceneries as well as results in the dwarfing phenomenon for precious cultural properties. That is, the preparation for supplementing the insufficient objectivity that is likely to take place during the process of drafting the standards on changes in current conditions. Thus the author attempts to suggest the analytic method for the decision making related to objective and reasonable determination and regulation of the changes in current conditions through computer based simulation work that considers the cultural properties and surrounding environments under investigation. In order to achieve such research objectives, the author reviewed the subject sites where the cultural property dwarfing phenomenon was expected to occur in case of the permission for the changes in current conditions or where the impact of natural landscape and natural feature on the earth is less than architectural building or artificial structure or where the new policy program is likely to be adopted due to incomplete establishment of current condition change standard within influence investigation area, among other cultural properties with architectural building or artificial structure nearby located in Cheonan city and then selected Cheonansaji Dangganjiju(flag poles) and Jiksanhyun Gwana(government office). The author then undertook the quantitative visibility analysis in order to determine the comprehensive prospect rights for the cultural properties and surrounding environments concerned.

Study on the Textile Design using Buttons on Western clothing in the 18th·19th Centuries (18·19세기 서양 복식의 단추를 활용한 텍스타일 디자인 연구)

  • Lee, Eui-Jung;Kang, Kyung-Ae
    • Journal of the Korea Fashion and Costume Design Association
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    • v.24 no.2
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    • pp.97-115
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    • 2022
  • The study aims to explore a new direction for research on buttons by understanding the functions and artistic features of buttons on Western clothing in the 18th and 19th centuries, and to use the findings to develop a textile design. In terms of the research method, the period was set in the 18th and 19th centuries, when decorative features and artistic values of buttons on Western clothing reached theirpeak, while theoretical analysis was made based on literature and previous research papers on Western clothing, websites of the Metropolitan Museum and French Museum of Decorative Arts and other website materials, as well as special exhibition materials of the National Museum of Modern and Contemporary Art. Textile designs were developed using computer programs, including Clip Studio Paint and Adobe Photoshop, by integrating the reinterpreted motif of buttons in the 18th and 19th centuries and the styles that prevailed at that time. The results are as follows. First, buttons on Western clothing had the following three functions: a practical function, a symbolic function representing the wearer's status, and a decorative function expressing individuality and beauty. Second, buttons in the 18th century were works of art made with various handicraft techniques and were an important medium that expressed the wearer's fashion sense. In addition, buttons in the 19th century were mass-produced as a result of industrialization and took a major step forward with the development of materials and dyeing. Buttons reflected themes of poetry, drama, biblical stories, music and art, lifestyle,, along with the political and social atmosphere that rapidly changed after the revolution and fashion trends. Third, the artistic features and shapes of buttons were reinterpreted to create a design motif, and the design was developed reflecting the characteristic elements of the rococo style of the 18th century and the art nouveau style of the 19th century that can conform to modern fashion, thereby rediscovering the artistic meaning and value implied in buttons. In the future, the research on creative buttons of 20th century artists is expected to be conducted from various perspectives.

A SVR Based-Pseudo Modified Einstein Procedure Incorporating H-ADCP Model for Real-Time Total Sediment Discharge Monitoring (실시간 총유사량 모니터링을 위한 H-ADCP 연계 수정 아인슈타인 방법의 의사 SVR 모형)

  • Noh, Hyoseob;Son, Geunsoo;Kim, Dongsu;Park, Yong Sung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.3
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    • pp.321-335
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    • 2023
  • Monitoring sediment loads in natural rivers is the key process in river engineering, but it is costly and dangerous. In practice, suspended loads are directly measured, and total loads, which is a summation of suspended loads and bed loads, are estimated. This study proposes a real-time sediment discharge monitoring system using the horizontal acoustic Doppler current profiler (H-ADCP) and support vector regression (SVR). The proposed system is comprised of the SVR model for suspended sediment concentration (SVR-SSC) and for total loads (SVR-QTL), respectively. SVR-SSC estimates SSC and SVR-QTL mimics the modified Einstein procedure. The grid search with K-fold cross validation (Grid-CV) and the recursive feature elimination (RFE) were employed to determine SVR's hyperparameters and input variables. The two SVR models showed reasonable cross-validation scores (R2) with 0.885 (SVR-SSC) and 0.860 (SVR-QTL). During the time-series sediment load monitoring period, we successfully detected various sediment transport phenomena in natural streams, such as hysteresis loops and sensitive sediment fluctuations. The newly proposed sediment monitoring system depends only on the gauged features by H-ADCP without additional assumptions in hydraulic variables (e.g., friction slope and suspended sediment size distribution). This method can be applied to any ADCP-installed discharge monitoring station economically and is expected to enhance temporal resolution in sediment monitoring.

Study on Image Use for Plant Disease Classification (작물의 병충해 분류를 위한 이미지 활용 방법 연구)

  • Jeong, Seong-Ho;Han, Jeong-Eun;Jeong, Seong-Kyun;Bong, Jae-Hwan
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.2
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    • pp.343-350
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    • 2022
  • It is worth verifying the effectiveness of data integration between data with different features. This study investigated whether the data integration affects the accuracy of deep neural network (DNN), and which integration method shows the best improvement. This study used two different public datasets. One public dataset was taken in an actual farm in India. And another was taken in a laboratory environment in Korea. Leaf images were selected from two different public datasets to have five classes which includes normal and four different types of plant diseases. DNN used pre-trained VGG16 as a feature extractor and multi-layer perceptron as a classifier. Data were integrated into three different ways to be used for the training process. DNN was trained in a supervised manner via the integrated data. The trained DNN was evaluated by using a test dataset taken in an actual farm. DNN shows the best accuracy for the test dataset when DNN was first trained by images taken in the laboratory environment and then trained by images taken in the actual farm. The results show that data integration between plant images taken in a different environment helps improve the performance of deep neural networks. And the results also confirmed that independent use of plant images taken in different environments during the training process is more effective in improving the performance of DNN.

Consumerism Interpretation of Character Tragedies in the Movie Lolita (영화 <로리타> 인물 비극의 소비주의 연구)

  • Guan, Meng-Ting
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.5
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    • pp.91-97
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    • 2019
  • The movie Lolita is directed by the famous director Stanley Kubrick in the United Kingdom in 1962. Due to the movie theme, it produced a great social dispute at that year. Lolita was Stanley Kubrick's first independently produced film. It tells the story of the abnormal love between Professor Humbert from Europe and his stepdaughter Lolita. Throughout the film, it shocked people by feeling honourable and aesthetic although the theme is about commit incest. The director also completely shown the social reality of the United States in a black humor irony method. By the meantime, the lush tragic feature of the film also strongly infects the audience. Current studies on the movie Lolita mainly focus on the following aspects: firstly, the black humor techniques of director Kubrick's movies, secondly, the parody techniques of the movie, and thirdly, the differences between the original novel Lolita and the adapted movie. In the American society where consumerism constitutes the mainstream, instead of sticking to traditional moral concepts, people pursue material enjoyment. Based on the consumerism theory, this paper analyzes the social reality revealed by the movie Lolita, presents such typical characteristics of the consumerist society as hedonism and broken family relations, and explains how the consumerist society leads to Lolita's tragic life.