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International Conference on Photonics (ICP)

作者： A. S. M. Noor M. S. Z. Abidin Y. Kawata Department of Mechanical Engineering Shizuoka University Hamamatsu Japan Department of Computer and Communication System Engineering Faculty of Engineering Universiti Putra Malaysia Selangor Darul Ehsan Malaysia

Two-photon excitation techniques used in fabricating lines defects were done on a light emitting diode chip. Simultaneous detection of a quenched wide-gap semiconductor crystal has been observed using single- and two-photon photoluminescence. It was found at the quenched area, single-photon excitation gives photoluminescence read-out compared to two-photon excitation which no photoluminescence detected at the bandgap wavelength. This is due to the excitation states which the transition of electron for two-photon excitation to occur have been demolished by the annealing of the sample which involved two-photon quenching process. The dependency of excitation power with respective photoluminescence is elaborated to confirmed the single- and two-photon excitation photoluminescence methods.

关键词： Photoluminescence Light emitting diodes Photonic band gap Crystals Lenses Fabrication

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3D Scientific Data Mining in Ion Trajectories

3D Scientific Data Mining in Ion Trajectories

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International Workshop on Knowledge Discovery and Data Mining (WKDD)

作者： J.M. Sharif M. Mahadi Abdul Jamil Md. Asri Ngadi M. Shafie Latiff Department of Computer System & Communication Universiti Teknologi Malaysia Malaysia Department of Electronic Engineering Universiti Tun Hussein Onn Malaysia Malaysia

In physics, structure of glass and ion trajectories are essentially based on statistical analysis of data acquired through experimental measurement and computer simulation. Invariably, the details of the structure-transport relationships in the data have been mistreated in favour of ensemble average. In this study, we demonstrate a visual approach of such relationship using surface-based visualisation schemes. In particular, we demonstrate a scientific datasets of simulated 3D time-varying model and examine the temporal correlation among ion trajectories. We propose a scheme that uses a three dimensional visual representation with colour scale for depicting the timeline events in ion trajectories and this scheme could be divided into two major part such as global and local time scale. With a collection of visual examples from this study, we demonstrate that this scheme may offer an effective tool for visually mining 3D timeline events of the ion trajectories. This work will potentially form a basis of a novel analysis tool for measuring the effectiveness of visual representation to assist physicist in identifying possible temporal association among complex and chaotic atom movements in ion trajectories.

关键词： Data mining Atomic measurements Data visualization Biomedical imaging Shape Solid modeling Deformable models Physics computing Glass Statistical analysis

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Automatic identification of trabecular bone fracture

Automatic identification of trabecular bone fracture

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12th Mediterranean Conference on Medical and Biological engineering and Computing, MEDICON 2010

作者： Tassani, S. Asvestas, P.A. Matsopoulos, G.K. Baruffaldi, F. Institute of Communication and Computer System School of Electrical and Computer Engineering National Technical University of Athens Athens Greece Laboratorio di Tecnologia Medica Istituti Ortopedici Rizzoli via di Barbiano 1/10 Bologna Italy Department of Medical Instruments Technology Faculty of Technological Applications Technological Educational Institute of Athens Athens Greece

ISBN: (纸本)9783642130380

The correct assessment of bone fracture risk is a mandatory issue for the application of efficient therapeutic scheme. However, it is still not clear which parameter can better predict the probability of a broken event. The correct identification of the fracture zone is a prerequisite in order to recognize the best parameter describing the bone failure. The in-vitro analysis of trabecular bone by means of micro tomographic devices (micro-CT) is a common technique for the study of bone structure. In this scenario image guide failure analysis is becoming a powerful tool for the characterization of trabecular bone mechanical behavior. In the present study the application of image registration techniques is proposed for the rapid and precise identification of the broken fracture. Five trabecular bone specimens were acquired by means of a micro-CT before and after the mechanical compression. The two datasets of every specimen were registered using a surface based automatic method and the broken region was identified as the only region not registered. The automatic procedure was finally validated comparing its results to the visual identification of three operators independently. The procedure resulted in complete agreement in 7 cases out of 10. For the three remaining cases, the operators had to compare their findings against the ones suggested by the automatic registration procedure. In all three cases, the operators had to correct their findings suggesting that the proposed automatic registration procedure was successfully performed and the identification of the fracture zone was correct. In conclusion, a novel procedure for the identification of trabecular bone fracture zone was presented and validated throughout this study. © 2010 International Federation for Medical and Biological engineering.

关键词： Bone

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Reflective type liquid refractometer based on multiple total internal reflections and attenuated total reflections in heterodyne interferometry

Reflective type liquid refractometer based on multiple total...

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IEEE Instrumentation and Measurement Technology Conference

作者： Shinn-Fwu Wang Chun-Wei Huang Che-Yu Liu Wesley Lai Meng-Feng Hsieh Hung-Chen Chung Jyh-Shyan Chiu Yun Hsiang Liao Rih-Huei Yeh Department of Electronic Engineering Ching Yun University of Technology Taoyuan Taiwan Institute of Computer Communication and System Engineering Ching Yun University of Technology Taoyuan Taiwan

In this paper, a reflective type liquid refractometer based on multiple attenuated total reflections and total internal reflections in heterodyne interferometry is proposed. The liquid refractometer is designed as a reflective elongated prism that is made of BK7 glass. The shorter-side surface of the reflective elongated prism was coated with 2 nm Ti-film and 45.5 nm Au-film, but the longer-side surface of that was not coated with metal films. With the new type liquid refractometer, the refractive index for the tested medium can be obtained only by measuring the phase difference between the p-and s-polarization lights due to the multiple attenuated total reflections and total internal reflections effects. Its resolution can reach 1' 10 -6 refractive index unit (RIU). The reflective type liquid refractometer has some merits, e.g., high resolution, high sensitivity, stability, and in real-time test, etc.

关键词： Interferometry Optical reflection Optical refraction Refractive index Testing Glass Optical films Attenuation measurement Phase measurement Stability

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Exploiting proximal F/T measurements for the iCub active compliance

Exploiting proximal F/T measurements for the iCub active com...

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2010 IEEE/RSJ International Conference on Intelligent Robots and systems

作者： Matteo Fumagalli Marco Randazzo Francesco Nori Lorenzo Natale Giorgio Metta Giulio Sandini Robotics Brain and Cognitive Sciences Department Italian Institute of Technology Genoa Italy Department of Communication Computer and System Sciences Faculty of Engineering University of Genova Italy

During the last decades, interaction (with humans and with the environment) has become an increasingly interesting topic of research within the field of robotics. At the basis of interaction, a fundamental role is played by the ability to actively regulate the interaction forces. In this paper we propose a technique for controlling the interaction forces exploiting a proximal six axes force/torque sensor. The major assumption is the knowledge of the point where external forces are applied. The proposed approach is tested and validated on the four limbs of the iCub, a humanoid robot designed for research in embodied cognition. Remarkably, the proposed approach can be used to implement active compliance in other non passively back-drivable manipulators by simply inserting one or more force/torque sensor anywhere along the kinematic chain.

关键词： Joints Robot sensing systems Torque Transfer functions Iron Force

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Approximate optimal control for reaching and trajectory planning in a humanoid robot

Approximate optimal control for reaching and trajectory plan...

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2010 IEEE/RSJ International Conference on Intelligent Robots and systems

作者： S. Ivaldi M. Fumagalli F. Nori M. Baglietto G. Metta G. Sandini Robotics Brain and Cognitive Sciences Department Italian Institute of Technology Genoa Italy Department of Communication Computer and System Sciences Faculty of Engineering University of Genova Italy

Online optimal planning of robotic arm movement is addressed. Optimality is inspired by computational models, where a “cost function” is used to describe limb motions according to different criteria. A method is proposed to implement optimal planning in Cartesian space, minimizing some cost function, by means of numerical approximation to a generalized nonlinear model predictive control problem. The Extended RItz Method is applied as a functional approximation technique. Differently from other approaches, the proposed technique can be applied on platforms with strict control temporal constraints and limited processing capability, since the computational burden is completely concentrated in an off-line phase. The trajectory generation on-line is therefore computationally efficient. Task to joint space conversion is implemented on-line by a closed loop inverse kinematics algorithm, taking into account the robot's physical limits. Experimental results, where a 4DOF arm moves according to a particular nonlinear cost, show the effectiveness of the proposed approach, and suggest interesting future developments.

关键词： Robots Trajectory Joints Kinematics Approximation methods Optimization Planning

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Road pavement density analysis using a new non-destructive ground penetrating radar system

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Progress In Electromagnetics Research B 2010年第21期 399-417页

作者： Mardeni, R. Raja Abdullah, R.S.A. Shafri, H.Z.M. Faculty of Engineering Multimedia University Cyberjaya Selangor 63100 Malaysia Faculty of Engineering Department of Computer and Communication System Universiti Putra Malaysia Serdang Selangor 43400 Malaysia Faculty of Engineering Department of Civil Engineering Universiti Putra Malaysia Serdang Selangor 43400 Malaysia

Density is an important parameter to determine the strength of road, and it will ensure the safety of the use as well as maintaining the quality of road pavement. In this paper, the validation of GPR mixture model based on the microwave nondestructive free space method to determine the density of road pavement typed Hot Mix Asphalt (HMA) will be presented. The frequency range of operation used is 1.7-2.6GHz. The attenuation is a major factor for gathering the density of road pavement predictably. The existing mixture model has been used to produce simulation data for determining the predicted complex permittivity and attenuation due to various densities of road pavement. The GPR laboratory measurement is performed where the measured attenuation due to various densities was obtained. The comparison results between measurement and simulation were investigated, and the relative errors in between were calculated to see the performance of the model. The best performance of mixture model was selected due to the smallest mean error using the optimization technique. An improved attenuation formula or optimized mixture model was obtained from the optimization technique to produce the better model. The finding from the optimization process suggested that three additional constant parameters which are volume factor, permittivity factor and attenuation factor need to be included to improve the existing mixture model. The optimized mixture model is introduced as GPR mixture model in this work. The validation process at field test had been conducted to evaluate the performance of optimized GPR model and produce the error range from 3.3% and 4.7%. At the end of this project, the GPR mixture model can be used as a calibration curve where the values of predicted density of a given real road pavement can be read directly once the attenuation values are known.

关键词： Ground penetrating radar systems

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Performance analysis of random access in IEEE 802.16m system

Performance analysis of random access in IEEE 802.16m system

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International Conference on Information and communication Technology Convergence (ICTC)

作者： Hyun Lee Eunkyung Kim Sungkyung Kim Sungcheol Chang Chulsik Yoon Kyoung-Rok Cho Department of Computer and Communication Engineering ChungBuk National University Chungju South Korea Department of Wireless System Research Electronics and Telecommunications Research Institute Daejeon South Korea

IEEE 802.16m, also known as the WirelessMAN-Advanced air interface, system adopts a random access using CDMA (Code Division Multiple Access)-based random access and message-based random access. The message-based random access is intended to reduce access delay when random access load is low. However, CDMA-based random access is used as random access load increases due to failure of message-based random access. In this paper, we analyze the performance of the enhanced random access in the IEEE 802.16m system which supports message-based random access in addition to CDMA-based random access. The analysis and numerical results help understand the performance of random access in IEEE 802.16m with low delay and low collision probability.

关键词： Distance measurement Bandwidth Multiaccess communication Delay Resource management IEEE 802.16 Standards Binary codes

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A fuzzy inference system applied to defect detection in flat steel production

A fuzzy inference system applied to defect detection in flat...

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IEEE International Conference on Fuzzy systems (FUZZ-IEEE)

作者： Alice Borselli Valentina Colla Marco Vannucci Marco Veroli Communication and Perception Engineering PERCRO Laboratory Centre of Excellence of Information Pontedera Italy Department of Computer Science and System Engineering Antonio Ruberti University of Roma La Sapienza Rome Italy

Recently in many industrial fields the exploitation of vision systems for quality control had a considerable increase, which is mainly due to the technological progress experienced by such systems, that, with respect to the past, made their performance more appealing and more reliable while the associated costs are decreased. The advantages of these kind of systems in terms of savings in human resources and improved quality monitoring have become far more evident, by encouraging their adoption in a wide variety of production cycles. The present paper deals with the elaboration and information extraction from images, that represent portions of the surface of flat steel products, and describes an algorithm for defect detection and classification. The overall classification procedure is composed of a preliminary part that is mostly related to image processing and analysis, which aims at pointing out the defect (independently on the class it belongs to), as well as to the extraction of relevant features of the detected defect; the second part exploits a fuzzy inference system in order to analyze the type of defect and solves a classification problem that presently can be addressed only with the support of a human operator. Fuzzy inference systems are suitable to this application because they are able to mimic and reproduce the human reasoning.

关键词： Steel Surface treatment Feature extraction Shape Surface morphology Brightness

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TCP SYN flood detection based on payload analysis

TCP SYN flood detection based on payload analysis

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2010 8th IEEE Student Conference on Research and Development - engineering: Innovation and Beyond, SCOReD 2010

作者： Haris, S.H.C. Ahmad, R.B. Ghani, M.A.H.A. Waleed, Ghossoon M. School of Computer and Communication Engineering Universiti Malaysia Perlis P.O Box 77 d/a Pejabat Pos Besar 01000 Kangar Perlis Malaysia Department of Management Information System Applied Science University College of Administrative Science Villa 351 Road 141Block 340 Juffaie. Manama Bahrain

ISBN: (纸本)9781424486489

Transmission Control Protocol (TCP) Synchronized (SYN) Flood has become a problem to the network management to defend the network server from being attacked by the malicious attackers. The malicious attackers can easily exploit the TCP three-way handshake by making the server exhausted and unavailable with spoofed Internet Protocol (IP) address. The main problem in this paper is how to detect TCP SYN flood through network. This paper used anomaly detection to detect TCP SYN flood attack based on payload and unusable area in Hypertext Transfer Protocol (HTTP). The results show that the proposed detection method can detect TCP SYN Flood in the network through the payload. ©2010 IEEE.

关键词： Transmission control protocol

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