• Title/Summary/Keyword: absolute localization

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Development of parked vehicles searching system

  • Lim, Do-Hyung;Seo, Chang-Jun
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1464-1467
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    • 2005
  • In this research, we developed a system, which can find the location of vehicle when people park their cars in a big parking lot or large area. People can find their cars readily through this simple device and they can save their time and effort. This is the purpose of this research. Performing this, detection of electromagnetic wave's direction is needed and we used shielding effectiveness of electromagnetic waves for the method of it. An absolute coordinate indicates four directions (E, W, S, N) by using an electronic compass module, and it is needed for the localization. The device can check the received count of the electromagnetic waves coming from all other directions through the system, which is installed in the vehicle. The direction recorded the least received count would be the location of the parked vehicles. We can add on the function of this research by using the same frequency of cars alarm goods. Also, it is useful in the huge indoor parking lot.

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Characteristics of solutions in softening plasticity and path criterion

  • Chen, G.;Baker, G.
    • Structural Engineering and Mechanics
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    • v.16 no.2
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    • pp.141-152
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    • 2003
  • Characteristics of solutions of softening plasticity are discussed in this article. The localized and non-localized solutions are obtained for a three-bar truss and their stability is evaluated with the aid of the second-order work. Beyond the bifurcation point, the single stable loading path splits into several post-bifurcation paths and the second-order work exhibits several competing minima. Among the multiple post-bifurcation equilibrium states, the localized solutions correspond to the minimum points of the second-order work, while the non-localized solutions correspond to the saddles and local maximum points. To determine the real post-bifurcation path, it is proposed that the structure should follow the path corresponding to the absolute minimum point of the second-order work. The proposal is further proved equivalent to Bazant's path criterion derived on a thermodynamics basis.

Registration of Multiple CT Images Using Principal Axis-based Rigid Body Transformation (주축기반 강체변환을 이용한 다중 CT 영상의 정합)

  • 유선국;김용욱;이혜연;김희중;김기덕;김남현
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.8
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    • pp.500-505
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    • 2003
  • In this paper, the method to register multiple sets of skull CT images to absolute coordinate system is proposed. Contrary to correspondence paired mapping of previous techniques, four anatomical landmark points, three coplanar points and one non-coplanar point, compose three principal axes simple and unique for efficient registration by means of rigid body transformation. Throughout the numerical simulation with added random noises, the error performances in terms of different rotation and rounding-off of landmark points, and incorrect localization of anatomical landmark and target points are quantitatively analyzed to generalize the proposed technique. Experiments using real skull CT images demonstrate the feasibility for an efficient use in clinical practice.

Research to improve the performance of self localization of mobile robot utilizing video information of CCTV (CCTV 영상 정보를 활용한 이동 로봇의 자기 위치 추정 성능 향상을 위한 연구)

  • Park, Jong-Ho;Jeon, Young-Pil;Ryu, Ji-Hyoung;Yu, Dong-Hyun;Chong, Kil-To
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.12
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    • pp.6420-6426
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    • 2013
  • The indoor areas for the commercial use of automatic monitoring systems of mobile robot localization improves the cognitive abilities and the needs of the environment with this emerging and existing mobile robot localization, and object recognition methods commonly around its great sensor are leveraged. On the other hand, there is a difficulty with a problem-solving self-location estimation in indoor mobile robots using only the sensors of the robot. Therefore, in this paper, a self-position estimation method for an enhanced and effective mobile robot is proposed using a marker and CCTV video that is already installed in the building. In particular, after recognizing a square mobile robot and the object from the input image, and the vertices were confirmed, the feature points of the marker were found, and marker recognition was then performed. First, a self-position estimation of the mobile robot was performed according to the relationship of the image marker and a coordinate transformation was performed. In particular, the estimation was converted to an absolute coordinate value based on CCTV information, such as robots and obstacles. The study results can be used to make a convenient self-position estimation of the robot in the indoor areas to verify the self-position estimation method of the mobile robot. In addition, experimental operation was performed based on the actual robot system.

Target Localization and Dose Delivery Verification used a Water Phantom in Stereotactic Radiosurgery (정위적 방사선 수술에서 물팬텀을 이용한 목표점 및 전달 선량확인)

  • Kang, Young-Nam;Lee, Dong-Jun;Kwon, Soo-Il;Kwon, Yang
    • Progress in Medical Physics
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    • v.7 no.2
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    • pp.19-28
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    • 1996
  • It is important that the precise decision of the region and the accurate delivery of radiation dose required for treatment in the stereotactic radiosurgery. In this research, radiosurgery was carried with Leksell streotactic frame(LSF) which is especially developed water phantom to verify in experiment. Leksell Gamma Knife and LSF are used in radiosurgery is the spherical water phantom has the thickness of 2 mm, the radius of 160mm. The film for target localization and ionchamber for dose delivery was used in measurement instruments We compare the coordinate of target which is initialized by biplannar film with simple X-ray to the coordinate of film measured directly. The calculated dose by computer simulation and the measured dose by ionization chamber are compared. In this research, the target localization has the range ${\pm}$0.3mm for the acceptable error range and the absolute dose is :${\pm}$0.3mm for the acceptable error range. This research shows that the values measured by using the especially manufactured phantom are included the acceptable error range. Thus, this water phantom will be used continuously in the periodic quality assurance of Gamma Knife Unit and Leksell Stereotactic Frame.

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Performance Improvement Algorithm for Wireless Localization Based on RSSI at Indoor Environment (RSSI의 거리 추정 방식에 바탕을 둔 실내 무선 측위 성능 향상 알고리즘)

  • Park, Joo-Hyun;Lee, Jung-Kyu;Kim, Seong-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.4C
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    • pp.254-264
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    • 2011
  • In this paper, we propose two algorithm for improving the performance of wireless localization(Trilateration and Least Square) based on the range based approach method in indoor environment using RSSI for ranging distance. we propose a method to discriminate the case that has relatively large estimation errors in trilateration using Heron''s formula for the volume of a tetrahedron. And we propose the algorithm to process the discriminated types of distance using the absolute value calculated by Heron''s formula. In addition, we propose another algorithm for the case of which the number of anchor nodes larger than three. In this case, Residual Weighting Factor(RWGH) improves the performance of Least Square. However, RWGH requires many number of calculations. In this paper, we propose Iterative Weighted Centroid Algorithm(IWCA) that has better performance and less calculation than RWGH. We show the improvement of performance for two algorithms and the combination of these algorithm by using simulation results.

Quantitative Proteomics Towards Understanding Life and Environment

  • Choi, Jong-Soon;Chung, Keun-Yook;Woo, Sun-Hee
    • Korean Journal of Environmental Agriculture
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    • v.25 no.4
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    • pp.371-381
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    • 2006
  • New proteomic techniques have been pioneered extensively in recent years, enabling the high-throughput and systematic analyses of cellular proteins in combination with bioinformatic tools. Furthermore, the development of such novel proteomic techniques facilitates the elucidation of the functions of proteins under stress or disease conditions, resulting in the discovery of biomarkers for responses to environmental stimuli. The ultimate objective of proteomics is targeted toward the entire proteome of life, subcellular localization biochemical activities, and the regulation thereof. Comprehensive analysis strategies of proteomics can be classified into three categories: (i) protein separation via 2-dimensional gel electrophoresis (2-DE) or liquid chromatography (LC), (ii) protein identification via either Edman sequencing or mass spectrometry (MS), and (iii) proteome quantitation. Currently, MS-based proteomics techniques have shifted from qualitative proteome analysis via 2-DE or 2D-LC coupled with off-line matrix assisted laser desorption ionization (MALDI) and on-line electrospray ionization (ESI) MS, respectively, toward quantitative proteome analysis. In vitro quantitative proteomic techniques include differential gel electrophoresis with fluorescence dyes. protein-labeling tagging with isotope-coded affinity tags, and peptide-labeling tagging with isobaric tags for relative and absolute quantitation. In addition, stable isotope-labeled amino acids can be in vivo labeled into live culture cells via metabolic incorporation. MS-based proteomics techniques extend to the detection of the phosphopeptide mapping of biologically crucial proteins, which ale associated with post-translational modification. These complementary proteomic techniques contribute to our current understanding of the manner in which life responds to differing environment.

Controversies in Usefulness of EEG for Clinical Decision in Epilepsy: Cons. (간질 치료에서 뇌파의 임상적 유용성에 관한 논란: 부정적 관점에서)

  • Lee, Seo-Young;Lee, Sang-Kun;Kim, Nam Hee
    • Annals of Clinical Neurophysiology
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    • v.9 no.2
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    • pp.69-74
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    • 2007
  • Electroencephalogram (EEG) is a representative diagnostic tool in epilepsy. However, there are several points of debate on the role of EEG in diagnosis and management of epilepsy. We suggest that EEG has some limitations for differential diagnosis from nonepileptic episodic diseases, classification of epilepsy, prediction of recurrence, and evaluation of treatment response. Interictal EEG cannot diagnose or exclude epilepsy because interictal epileptic discharge (IED) is frequently absent in epilepsy and can appear in nonepileptic conditions. Although EEG is helpful in classification of epilepsy, focal spikes in generalized epilepsy and secondary bilateral synchrony in localization related epilepsy cause interrater disagreement. It is controversial whether EEG predicts recurrence after the first seizure in adults. The predictive value of EEG in antiepileptic drug (AED) withdrawal is not absolute. The prognosis after AED withdrawal depends on epilepsy syndrome. Many studies could not confirm the value of EEG in assessing the treatment response. After all, epilepsy is clinically diagnosed and assessed. Interictal EEG alone does not provide decisive information and routine follow-up of EEG is not recommended.

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4WS Unmanned Vehicle Lateral Control Using PUS and Gyro Coupled by Kalman Filtering

  • Lee, Kil-Soo;Park, Hyung-Gyu;Lee, Man-Hyung
    • Journal of Navigation and Port Research
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    • v.35 no.2
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    • pp.121-130
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    • 2011
  • The localization of vehicle is an important part of an unmanned vehicle control problem. Pseudolite ultrasonic system(PUS) is the method to find an absolute position with a high accuracy by using ultrasonic sensor. And Gyro is the inertial sensor to measure yaw angle of vehicle. PUS can be able to estimate the position of mobile robot precisely, in which errors are not accumulated. And Gyro is a more faster measure method than PUS. In this paper, we suggest a more accuracy method of calculating PUS which is numerical analysis approach named Newtonian method. And also propose the fusion method to increase the accuracy of estimated angle on moving vehicle by using PUS and Gyro integrated system by Kalman filtering. To control the 4WS unmanned vehicle, the trajectory following algorithm is suggested. And the new concept arbitration of goal controller is suggested. This method considers the desirability function of vehicle state. Finally, the performances of Newtonian method and designed controller were verified from the experimental results with the 4WS vehicle scaled 1/10.

Region of Interest Localization for Bone Age Estimation Using Whole-Body Bone Scintigraphy

  • Do, Thanh-Cong;Yang, Hyung Jeong;Kim, Soo Hyung;Lee, Guee Sang;Kang, Sae Ryung;Min, Jung Joon
    • Smart Media Journal
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    • v.10 no.2
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    • pp.22-29
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    • 2021
  • In the past decade, deep learning has been applied to various medical image analysis tasks. Skeletal bone age estimation is clinically important as it can help prevent age-related illness and pave the way for new anti-aging therapies. Recent research has applied deep learning techniques to the task of bone age assessment and achieved positive results. In this paper, we propose a bone age prediction method using a deep convolutional neural network. Specifically, we first train a classification model that automatically localizes the most discriminative region of an image and crops it from the original image. The regions of interest are then used as input for a regression model to estimate the age of the patient. The experiments are conducted on a whole-body scintigraphy dataset that was collected by Chonnam National University Hwasun Hospital. The experimental results illustrate the potential of our proposed method, which has a mean absolute error of 3.35 years. Our proposed framework can be used as a robust supporting tool for clinicians to prevent age-related diseases.