检索结果-内蒙古大学图书馆

Pressure dependence of Brillouin frequency shift in bare silica optical fibers

Chinese Optics Letters 2012年第10期10卷 20-22页

作者：顾海栋董惠娟张广玉何俊徐宁 Douglas.J.Brown School of Mechatronics Engineering Harbin Institute of Technology State Key Laboratory of Robotics and System Harbin Institute of Technology Department of Electrical and Computer Engineering University of New BrunswickFrederictonNB E3B 5A3Canada

The effect of hydrostatic pressure （up to 28 MPa） on Brillouin frequency shift （BFS） within two types of bare, single-mode fibers is studied via Brillouin optical time domain analysis technique. Experimental results show a negative linear relation between pressure and BFS, with almost the same sensitivity in both types of fibers. The average value of experimental slopes is –0.742 MHz/MPa. This value is found to be well suited to theoretical analysis on the basis of data on bulk silica glass in previous reports. This preliminary evaluation may result in a new method for distributed pressure sensing along silica optical fiber.

关键词： Frequency shift keying Hydrostatic pressure Silica Time domain analysis

来源：评论

学校读者我要写书评

暂无评论

Stochastic search strategies in 2D using agents with limited perception

引用

IFAC Proceedings Volumes 2012年第22期45卷 650-654页

作者： David Puljiz Maja Varga Stjepan Bogdan University of Zagreb Faculty of Electrical Engineering and Computing Department of Control and Computer Engineering LARICS–Laboratory for Robotics and Intelligent Control Systems Zagreb Croatia Laboratory of Intelligent Systems Ecole Polytechnique Federale de Lausanne 1015 Lausanne Switzerland

Animals use stochastic search strategies to find a potential nest or to localize the food source. Animals do not rely much on the environmental cues or their sensory inputs. Since their cognitive capabilities are rather limited, search strategies are usually simplistic and stochastic. And yet such simple search strategies result in high efficiency in finding potential targets in limited time intervals. Similar problems with perception of the environment and limited computational power and sensory inputs are observed on the mobile robots used in search scenarios. In spite of their limitations, such robotic systems usually perform deterministic search strategies which heavily depend on environmental cues and sensory input. The research question we are addressing in this paper is which stochastic search strategy has the best performance in terms of area coverage and can stochastic search strategies outperform deterministic search strategies.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Automatic segmentation of brain tumors in magnetic resonance images

Automatic segmentation of brain tumors in magnetic resonance...

引用

IEEE-EMBS International Conference on Biomedical and Health Informatics, BHI 2012. In Conj. with the 8th Int. Symp.on Medical Devices and Biosensors and the 7th Int. Symp. on Biomedical and Health engineering

作者： Behzadfar, Neda Soltanian-Zadeh, Hamid Control and Intelligent Processing Center of Excellence School of Electrical and Computer Engineering University of Tehran Tehran 14395-515 Iran Pooyandegan Rah Saadat Company Tehran 16756-965 Iran Image Analysis Laboratory Radiology Department HenryFord Healh System Detroit MI 48202 United States

ISBN: (纸本)9781457721779

Segmentation of tumors in magnetic resonance images (MRI) is an important task but is quite time consuming when performed manually by experts. Automating this process is challenging due to the high diversity in appearance of tumor tissue in different patients, and in many cases, similarity between tumor and normal tissues. This paper presents an automatic method for segmentation of brain tumors in MRI. We use images of patients with glioblastoma multiform tumors. After pre-processing and removal of the regions that do not have useful information (e.g., eyes and scalp), we create a projection image for determining the primary location of the tumor. This image provides an overall view of the tumor. Then, we grow the primary region to segment the entire tumor. This method is automatic and independent of the operator. It segments low contrast tumors without requiring their exacta tissue boundaries. The segmentation results obtained by the proposed approach are compared with those of an expert radiologist showing excellent correlations among them (R2=0.97). © 2012 IEEE.

关键词： Tumors

来源：评论

学校读者我要写书评

暂无评论

Voxel-based treatment prediction of glioblastoma multiform tumor using diffusion tensor imaging

Voxel-based treatment prediction of glioblastoma multiform t...

引用

作者： Sabahi, Hadi Soltanian-Zadeh, Hamid Scarpace, Lisa Mikkelsen, Tom Control and Intelligent Processing Center of Excellence School of Electrical and Computer Engineering University of Tehran Tehran 14395-515 Iran Image Analysis Laboratory Radiology Department Henry Ford Hospital Detroit MI 48202 United States Hermelin Brain Tumor Research Center Neurosurgery Department Henry Ford Health System Detroit MI 48202 United States

ISBN: (纸本)9781457721779

This paper proposes a method to predict the effect of Bevacizumab therapy on Glioblastoma Multiform (GBM) tumors. The prediction is critical for effective treatment planning. The proposed method is developed and evaluated using Diffusion Tensor Imaging (DTI) and post-contrast T1-weighted Magnetic Resonance Images (pc-T1-MRI) of 14 patients with GBM tumors gathered before and after the treatment. First, the proposed method calculates diffusion anisotropy indices (DAI) of all voxels in the brain. These diffusion anisotropy indices are Fractional Anisotropy (FA), Mean Diffusivity (MD), Relative Anisotropy (RA), and Volume Ratio (VR). Then, it registers post-treatment pc-T1-MRI and pre-treatment DAI maps to pre-treatment pc-T1-MRI. Next, it uses a thresholding method to segment the tumor from pc-T1-MRI studies. Comparing Gd-enhanced voxels of the pre- and post-treatment pc-T1-MRI, the DAIs of the tumor are labeled based on their response to the treatment. The voxels of 7 patients are randomly selected to train 4 classifiers (ANN, SVM, KNN, and ANFIS) and then all voxels of the other 7 patients are used to test them. For each classifier, four performance measures (sensitivity, specificity, positive predictive value, and accuracy) are calculated. Experimental results show that the ANFIS is more accurate than the other classifiers in predicting the treatment response. © 2012 IEEE.

关键词： Tumors

来源：评论

学校读者我要写书评

暂无评论

Age-Group Classification of Facial Images

Age-Group Classification of Facial Images

引用

International Conference on Machine Learning and Applications (ICMLA)

作者： Li Liu Jianming Liu Jun Cheng Shenzhen Institutes of Advanced Technolozv Chinese Academv of Science Computer Science and Engineering Department School of Guilin University of Electronic Technology Guilin China Guangdong Provincial Key Laboratory of Robotics and Intelligent System

This paper presents the age-group classification based on facial images. We perform age-group classification by dividing ages into five age groups according to the incremental regulation of age. Features are extracted from face images through Active Appearance Model (AAM), which describe the shape and gray value variation of face images. Principle Component Analysis (PCA) is adopted to reduce the dimensions and Support Vector Machine (SVM) classifier with Gaussian Radian Basis Function (RBF) kernel is trained. Experimental results demonstrate that AAM can improve the performance of age estimation.

关键词： Machine learning

来源：评论

学校读者我要写书评

暂无评论

Model-based real-time volume control for interactive network traffic replay

Model-based real-time volume control for interactive network...

引用

IEEE Symposium on Network Operations and Management

作者： Weibo Chu Xiaohong Guan Lixin Gao Zhongmin Cai MOE KLINNS Laboratory Xi'an Jiaotong University Xi'an China Center for Intelligent and Networked System and NLIST Laboratory Tsinghua University Beijing China Department of Electrical and Computer Engineering University of Massachusetts Amherst USA

Traffic volume control is one of the fundamental requirements in traffic generation and transformation. However, due to the complex interactions between the generated traffic and replay environment (delay, packet loss, connection blocking, etc), controlling traffic volume in interactive network traffic replay becomes a challenging problem. In this paper, we present a novel model-based analytical method to address this problem where the generated traffic volume is regulated through adjustment of input traffic volume. By analyzing the replay mechanism in terms of how packets are processed, and properly choosing buffered packets amount and to-be-received packets amount as system states, we present a novel model-based analytical method to obtain the desired input volume. The traffic volume control problem is then converted to a state prediction problem where we employ Recursive Least Square (RLS) filter to predict system states. As compared to other adaptive control techniques, our method does not involve any learning scheme and hence completely requires no convergence time. Experimental studies further indicate that our method is efficient in tracking target traffic volume (both static and time-varying) and works under a wide range of network conditions.

关键词： Solid modeling Analytical models Vectors Telecommunication traffic Testing Delay Target tracking

来源：评论

学校读者我要写书评

暂无评论

Recent advances on the energy management of a Hybrid Electric Vehicle

Recent advances on the energy management of a Hybrid Electri...

引用

Mediterranean Conference on Control & Automation

作者： D. S. Efstathiou A. K. Petrou P. Spanoudakis N. C. Tsourveloudis K. P. Valavanis Intelligent Systems and Robotics Lab Technical University of Crete Chania Greece Machine Tools Laboratory Technical University of Crete Chania Greece Department of Electrical and Computer Engineering University of Denver Denver CO 80208 USA

ISBN: (纸本)9781467325301

This paper presents new innovative subsystems of the ER11 prototype urban vehicle which is powered by hydrogen fuel cells and ultra-capacitors. The subsystems described here are: 1) the energy management system, which is responsible for the optimization of the fuel efficiency and the increased mileage of the vehicle, 2) the driver's monitoring and control panel and 3) the power transmission system, which offers the possibility of continuous change of gear. The powertrain of the test-bed vehicle consists of an electric motor, a fuel (Η2) cell system, an ultra-capacitor bank and a DC/DC converter. Testing verified that the proposed energy management system is benefitted by the variable transmission of power leading to less fuel consumption.

关键词： Recent advances energy management Hybrid Electric Vehicle

来源：评论

学校读者我要写书评

暂无评论

Optimal density estimation for exposure-path prevention in wireless sensor networks using percolation theory

Optimal density estimation for exposure-path prevention in w...

引用

IEEE Annual Joint Conference: INFOCOM, IEEE computer and Communications Societies

作者： Liang Liu Xi Zhang Huadong Ma Beijing Key Laboratory of Intelligent Telecommunication Software and Multimedia Beijing University-áof Posts and-áTelecommunications Beijing China Networking and Information System Laboratory Department of Electrical and Computer Engineering Texas A and M University College Station TX USA

ISBN: (纸本)9781467307734;9781467307758

Most existing works on sensor coverage mainly concentrate on the full coverage models which ensure that all points in the deployment region are covered at the expense of high complexity and cost. In contrast, the exposure-path prevention does not require full coverage sensor deployment, and instead it only needs the partial coverage, because the exposure paths are prevented as long as no moving objects or phenomena can go through a deployment region without being detected. Towards this end, we focus on the partial coverage by applying the percolation theory to solve the exposure path problem for wireless sensor networks. Specifically, we propose a bond-percolation based scheme by mapping the exposure path problem into a bond percolation model. Using this model, we derive the analytical expressions of critical densities for wireless sensor networks under random sensor deployment.

关键词： Lattices Wireless sensor networks Simulation Upper bound Educational institutions Approximation methods Wireless networks

来源：评论

学校读者我要写书评

暂无评论

A binary-classification-tree based framework for distributed target classification in multimedia sensor networks

A binary-classification-tree based framework for distributed...

引用

IEEE Annual Joint Conference: INFOCOM, IEEE computer and Communications Societies

作者： Liang Liu Anlong Ming Huadong Ma Xi Zhang Beijing Key Laboratory of Intelligent Telecommunication Software and Multimedia Beijing University슠of Posts and슠Telecommunications Beijing China Networking and Information System Laboratory Department of Electrical and Computer Engineering Texas A and M University College Station TX USA

ISBN: (纸本)9781467307734;9781467307758

With rapid improvements and miniaturization in hardware, sensor nodes equipped with acoustic and visual information collection modules promise an unprecedented opportunity for target surveillance applications. This paper investigates a critical task of target surveillance, multi-class classification, in distributed multimedia sensor networks. We first analyze the procedure of target classification utilizing the acoustic and visual information. Then, we propose a binary classification tree based framework for distributed target classification in multimedia sensor networks. The proposed framework includes three main components: Generation of binary classification tree, Division of binary classification tree, and Selection of multimedia sensor nodes. Finally, we conduct an experimental application of target classification and extensive simulations to validate and evaluate our proposed framework and related schemes.

关键词： Multimedia communication Feature extraction Acoustics Visualization Support vector machines Training Wireless sensor networks

来源：评论

学校读者我要写书评

暂无评论

Physarum optimization: A biology-inspired algorithm for minimal exposure path problem in wireless sensor networks

Physarum optimization: A biology-inspired algorithm for mini...

引用

IEEE Annual Joint Conference: INFOCOM, IEEE computer and Communications Societies

作者： Liang Liu Yuning Song Huadong Ma Xi Zhang Beijing Key Laboratory of Intelligent Telecommunication Software and Multimedia Beijing University슠of Posts and슠Telecommunications Beijing China Networking and Information System Laboratory Department of Electrical and Computer Engineering Texas A and M University College Station TX USA

ISBN: (纸本)9781467307734;9781467307758

Using insights from biological processes could help to design new optimization techniques for long-standing computational problems. This paper exploits a cellular computing model in the slime mold physarum polycephalum to solve the minimal exposure path problem which is a fundamental problem corresponding to the worst-case coverage in wireless sensor networks. We first formulate the minimal exposure path problem, and then convert it into the shortest path problem by discretizing the monitoring field to a large-scale weighted grid. Inspired by the path-finding capability of physarum, we develop a new optimization algorithm, named as the physarum optimization, for solving the shortest path problem. Our proposed algorithm is with low-complexity and high-parallelism. Moreover, the core mechanism of our physarum optimization is also helpful for designing new graph algorithms and improving routing protocols and topology control in self-organized networks.

关键词： Mathematical model Electron tubes Optimization Computational modeling Equations Organisms

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：