• Title/Summary/Keyword: Alignment Model

Search Result 461, Processing Time 0.028 seconds

A Study of the Multiheading INS Alignment (Multiheading 방법을 이용한 INS의 초기정렬에 관한 연구)

  • 윤희광;송택렬
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.98-98
    • /
    • 2000
  • In this paper, we present a Multiheading Method for INS initial. The system is not observable for initial alignment however using pseudo tilt angles and pseudo sensor errors become observable. We suggest a new Multiple Method to find the real sensor errors by using the converted system dynamics. The results show that we can find the sensor errors very accurately by the proposed method.

  • PDF

Face Tracking System using Active Appearance Model (Active Appearance Model을 이용한 얼굴 추적 시스템)

  • Cho, Kyoung-Sic;Kim, Yong-Guk
    • 한국HCI학회:학술대회논문집
    • /
    • 2006.02a
    • /
    • pp.1044-1049
    • /
    • 2006
  • 얼굴 추적은 Vision base HCI의 핵심인 얼굴인식, 표정인식 그리고 Gesture recognition등의 다른 여러 기술을 지원하는 중요한 기술이다. 이런 얼굴 추적기술에는 영상(Image)의 Color또는 Contour등의 불변하는 특징들을 사용 하거나 템플릿(template)또는 형태(appearance)를 사용하는 방법 등이 있는데 이런 방법들은 조명환경이나 주위 배경등의 외부 환경에 민감하게 반응함으로 해서 다양한 환경에 사용할 수 없을 뿐더러 얼굴영상만을 정확하게 추출하기도 쉽지 않은 실정이다. 이에 본 논문에서는 deformable한 model을 사용하여 model과 유사한 shape과 appearance를 찾아 내는 AAM(Active Appearance Model)을 사용하는 얼굴 추적 시스템을 제안하고자 한다. 제안된 시스템에는 기존의 Combined AAM이 아닌 Independent AAM을 사용하였고 또한 Fitting Algorithm에 Inverse Compositional Image Alignment를 사용하여 Fitting 속도를 향상 시켰다. AAM Model을 만들기 위한 Train set은 150장의 4가지 형태에 얼굴을 담고 있는 Gray-scale 영상을 사용 하였다. Shape Model은 각 영상마다 직접 표기한 47개의 Vertex를 Trianglize함으로서 생성되는 71개의 Triangles을 하나의 Mesh로 구성하여 생성 하였고, Appearance Model은 Shape 안쪽의 모든 픽셀을 사용해서 생성하였다. 시스템의 성능 평가는 Fitting후 Shape 좌표의 정확도를 측정 함으로서 평가 하였다.

  • PDF

Precision Evaluation of Scanning the Digital Dental Abutment Impression and Dental Gypsum Model according to 3-dimensional Superimposing Different Skills (3차원 중첩 기술 차이에 따른 디지털 치과용 지대치 인상체 및 경석고 모형의 스캐닝 정밀도 평가)

  • Jeon, Jin-Hun
    • The Journal of the Korea Contents Association
    • /
    • v.18 no.12
    • /
    • pp.639-645
    • /
    • 2018
  • The objective of this research was to compare the precision of scanning the digital abutment impression and gypsum model according to 3-dimensional superimposing different skills. There were made with the abutment impression and gypsum model of a maxillary 1st premolar, blue light scanner scanned to obtain the stereolithography (STL) file. After the same process was performed 10 more times without moving them on the scanner table about the abutment impression and gypsum model, respectively (n=11, per types). By superimposing the date of scanning the abutment impression and gypsum model used with no control and best-fit-alignment skills, 10 color-difference maps and root mean square (RMS) data were obtained. The independent t-test was performed to compare RMS data between the each other groups (${\alpha}=0.05$). In the scanning abutment impressions, $RMS{\pm}SD$ of no control, best-fit-alignment showed $6.86{\pm}0.94$, $5.04{\pm}0.24$. in the scanning gypsum model, $4.98{\pm}1.16$, $3.39{\pm}0.07$, all groups showed a significant difference (P<0.001). Trough the this study's result, not only best-fit-alignment but no control is used with digital dental computer-aided design/computer-aided manufacturing (CAD/CAM) research and clinical part.

Information Modeling of Railway Track using Information Iinkage of Railway Alignment and Alignment-based Objects (철도 선형중심의 객체 정보연계를 통한 철도 궤도부 정보모델 생성 방안)

  • Kwon, Tae Ho;Park, Sang I.;Shin, Min Ho;Lee, Sang-Ho
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.30 no.6
    • /
    • pp.507-514
    • /
    • 2017
  • As BIM has been widely used in the field of architecture, efforts to apply BIM to civil engineering structures are increasing rapidly. Since commercial BIM softwares are focused on building structure, it is difficult to apply to alignment-based civil infrastructures. In this study, we proposed a method to generate an information model that reflects cant by sharing information between alignment-centered modeling tools and BIM authoring tools to manage information of railway track. The railway track modeling process consists of classifying structures into continuous and non-continuous structures, creating continuous structures by alignment-centered modeling tools, and using the shared alignment information to generate information model of the non-continuous structures. Non-continuous structures were generated by an algorithm that calculates the position and rotation information of each structure based on discretized railway alignment and cant information transmitted to the BIM authoring tools. The availabilities of proposed method were studied by applying to the osong test-line. Using the test model, it was shown that the objects were identified, the properties were extracted, and the quantities of each structure were calculated.

In silico Analysis on hERG Channel Blocking Effect of a Series of T-type Calcium Channel Blockers

  • Jang, Jae-Wan;Song, Chi-Man;Choi, Kee-Hyun;Cho, Yong-Seo;Baek, Du-Jong;Shin, Kye-Jung;Pae, Ae-Nim
    • Bulletin of the Korean Chemical Society
    • /
    • v.32 no.1
    • /
    • pp.251-262
    • /
    • 2011
  • Human ether-a-go-go related gene (hERG) potassium channel blockade, an undesirable side effect which might cause sudden cardiac death, is one of the major concerns facing the pharmaceutical industry. The purpose of this study is to develop an in silico QSAR model which uncovers the structural parameters of T-type calcium channel blockers to reduce hERG blockade. Comparative molecular similarity indices analysis (CoMSIA) was conducted on a series of piperazine and benzimidazole derivatives bearing methyl 5-(ethyl(methyl)amino)-2-isopropyl-2-phenylpentanoate moieties, which was synthesized by our group. Three different alignment methods were applied to obtain a reliable model: ligand based alignment, pharmacophore based alignment, and receptor guided alignment. The CoMSIA model with receptor guided alignment yielded the best results : $r^2$ = 0.955, $q^2$ = 0.781, $r^2_{pred}$ = 0.758. The generated CoMSIA contour maps using electrostatic, hydrophobic, H-bond donor, and acceptor fields explain well the structural requirements for hERG nonblockers and also correlate with the lipophilic potential map of the hERG channel pore.

A Novel Two-Stage Training Method for Unbiased Scene Graph Generation via Distribution Alignment

  • Dongdong Jia;Meili Zhou;Wei WEI;Dong Wang;Zongwen Bai
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.17 no.12
    • /
    • pp.3383-3397
    • /
    • 2023
  • Scene graphs serve as semantic abstractions of images and play a crucial role in enhancing visual comprehension and reasoning. However, the performance of Scene Graph Generation is often compromised when working with biased data in real-world situations. While many existing systems focus on a single stage of learning for both feature extraction and classification, some employ Class-Balancing strategies, such as Re-weighting, Data Resampling, and Transfer Learning from head to tail. In this paper, we propose a novel approach that decouples the feature extraction and classification phases of the scene graph generation process. For feature extraction, we leverage a transformer-based architecture and design an adaptive calibration function specifically for predicate classification. This function enables us to dynamically adjust the classification scores for each predicate category. Additionally, we introduce a Distribution Alignment technique that effectively balances the class distribution after the feature extraction phase reaches a stable state, thereby facilitating the retraining of the classification head. Importantly, our Distribution Alignment strategy is model-independent and does not require additional supervision, making it applicable to a wide range of SGG models. Using the scene graph diagnostic toolkit on Visual Genome and several popular models, we achieved significant improvements over the previous state-of-the-art methods with our model. Compared to the TDE model, our model improved mR@100 by 70.5% for PredCls, by 84.0% for SGCls, and by 97.6% for SGDet tasks.

The uniform observability and the error characteristics for stationary strapdown inertial navigation system (스트랩다운 관성항법시스템의 정지시 균일 관측 가능성 및 오차 특성 분석)

  • 정도형;박찬국;이장규
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1996.10b
    • /
    • pp.676-679
    • /
    • 1996
  • In this paper, the uniform observability and the error characteristics for stationary SDINS error are analyzed. The use of the Lyapunov transformation is proposed for transforming te conventional SDINS error model and the sufficient conditions for the uniform observability of SDINS error model are analytically derived. A complete characterization for the SDINS error characteristics during two position alignment is presented which allows us to predict the performance of two position alignment in SDINS.

  • PDF

Velocity Matching Algorithm Using Robust H₂Filter (강인 H₂필터를 이용한 속도정합 알고리즘)

  • Yang, Cheol Gwan;Sim, Deok Seon;Park, Chan Guk
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.7 no.4
    • /
    • pp.363-363
    • /
    • 2001
  • We study on the velocity matching algorithm for transfer alignment of inertial navigation system(INS) using a robust H₂ filter. We suggest an uncertainty model and a discrete robust H₂filter for INS and apply the suggested robust H₂ filter to the uncertainty model. The discrete robust H₂filter is shown by simulation to have better performance time and accuracy than Kalman filter.

Robust Face Alignment using Progressive AAM (점진적 AAM을 이용한 강인한 얼굴 윤곽 검출)

  • Kim, Dae-Hwan;Kim, Jae-Min;Cho, Seong-Won;Jang, Yong-Suk;Kim, Boo-Gyoun;Chung, Sun-Tae
    • The Journal of the Korea Contents Association
    • /
    • v.7 no.2
    • /
    • pp.11-20
    • /
    • 2007
  • AAM has been successfully applied to face alignment, but its performance is very sensitive to initial values. In this paper, we propose a face alignment method using progressive AAM. The proposed method consists of two stages; modelling and relation derivation stage and fitting stage. Modelling and relation derivation stage first builds two AAM models; the inner face AAM model and the whole face AAM model and then derive the relation matrix between the inner face AAM model parameter vector and the whole face AAM model parameter vector. The fitting stage is processed progressively in two phases. In the first phase, the proposed method finds the feature parameters for the inner facial feature points of a new face, and then in the second phase it localizes the whole facial feature points of the new face using the initial values estimated utilizing the inner feature parameters obtained in the first phase and the relation matrix obtained in the first stage. Through experiments, it is verified that the proposed progressive AAM-based face alignment method is more robust with respect to pose, and face background than the conventional basic AAM-based face alignment.

Statistical Modeling of Pretilt Angle Control using Ion-beam Alignment on Nitrogen Doped Diamond-like Carbon Thin Film

  • Kang, Hee-Jin;Lee, Jung-Hwan;Han, Jung-Min;Yun, Il-Gu;Seo, Dae-Shik
    • Transactions on Electrical and Electronic Materials
    • /
    • v.7 no.6
    • /
    • pp.297-300
    • /
    • 2006
  • The response surface modeling of the pretilt angle control using ion-beam (IB) alignment on nitrogen doped diamond-like carbon (NDLC) thin film layer is investigated. This modeling is used to analyze the variation of the pretilt angle under various process conditions. IB exposure angle and IB exposure time are considered as input factors. The analysis of variance technique is settled to analyze the statistical significance, and effect plots are also investigated to examine the relationships between the process parameters and the response. The model can allow us to reliably predict the pretilt angle with respect to the varying process conditions.