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991.
Y. Lao C. H. Leung Y. S. Hung 《International journal of imaging systems and technology》2005,15(4):211-219
A method for identifying the same running vehicle from images captured at different camera sites is proposed. This is achieved through an image matching process. With cameras installed at the inlets and exits of highways and at crossroads in a road network, the system can be used for tracking the routes of individual vehicles and computing the times of traveling from one site to another. The system has the advantages of being low cost and not requiring sophisticated imaging hardware. Contributions include (i) a novel background removal method that employs the robust RANSAC algorithm for estimation, (ii) an elaborate shadow removal algorithm, and (iii) an effective license plate matching method applicable to poor quality images.© 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 15, 211–219, 2005 相似文献
992.
An Information Service for Grid Virtual Organization: Architecture, Implementation and Evaluation 总被引:1,自引:0,他引:1
Information Service is the heart of the entire Grid software infrastructure. It maintains various information in a Grid environment, and provides this information to users on request. We present an Information Service architecture for information capturing, aggregation, and provisioning in a Grid Virtual Organization (VO). This Information Service is a hierarchical structure which consists of VO layer, site layer and resource layer. The architecture defines downloadable and pluggable information sensors for portability and flexibility of information capturing. The meta-data mechanism is incorporated into our Information Service for information organization and management. Experiments were conducted to evaluate the performance of the Information Service, and the results show that the Information Service presents satisfactory scalability with number of users and number of information amount. Our Information Service has been implemented based on the Globus Toolkit as a Grid service compliant to the Open Grid Services Architecture (OGSA) specifications. 相似文献
993.
Hung Shao-Shin Kuo Ting-Chia Liu Damon Shing-Min 《Journal of Intelligent Manufacturing》2005,16(6):587-597
Mining of sequential patterns in walkthrough systems is an interesting data mining problem. It can be envisioned as a tool
for forecasting and prediction of the future behavior of user’s traversal patterns. In the past, how to display the object
faster in the next time were their concerns. They seldom consider the problem of access times of objects in the storage systems.
In this paper, we will consider this problem and solve this by clustering. Clustering methodology is particularly appropriate
for the exploration of interrelationships among objects to reduce the access times of objects. We record the user’s path as
log-data and store it in database. After a certain period of time, we will process the log-data database for user traversal
paths and find out their characteristics, which will be utilized to determine the optimal physical organization of those VRML
objects on disks. Meanwhile, we also introduce the relationships among transactions, views and objects. According to these
relationships, we suggest the clustering criteria--inter-pattern similarity, which utilize these characteristics to distribute
the objects into the appropriate clusters. As a result, the large-scale VRML models could be accessed more efficiently, allowing
for a real-time walk-through in the scene.
Author for correspondence and also is an instructor of WuFeng Institute of Technology. 相似文献
994.
Min-Hang Weng Cheng-Yuan Hung Yan-Kuin Su 《Microwave and Wireless Components Letters, IEEE》2007,17(7):519-521
A high performance hairpin line diplexer for the direct sequence ultra-wideband communication is designed and implemented. This microstrip diplexer is mainly composed of two hairpin line wideband bandpass filters and a tapped open stub. The design concept is proposed in detail and has been verified by the experimental results of the fabricated diplexer, including the two isolated wideband bandwidths of 3.1-5.0 GHz and 6.02-10 GHz, low insertion loss and high isolation. Experimental results also show a good agreement with the simulated results. 相似文献
995.
Hung-Wei Wu Min-Hang Weng Yan-Kuin Su Ru-Yuan Yang Cheng-Yuan Hung 《Microwave and Wireless Components Letters, IEEE》2007,17(9):673-675
This letter investigates the equivalent lumped elements of the thin film microstrip line (TFML) with different DC-bias voltages for the first time. The wide-band frequency-dependent characteristic impedance Zo(f) and equivalent lumped elements such as R(f), L(f), G(f), and C(f) are accurately characterized for DC-biased TFML on a 20-m thick low dielectric constant (K) polyimide up to 50 GHz. The experimental results shows the DC-biased TFML can be extensively applied to the voltage-controlled passive and active integrated circuits. 相似文献
996.
Yu-Chueh Hung Soeng Ku Kim Fetterman H. Jingdong Luo Jen A.K-Y. 《Photonics Technology Letters, IEEE》2007,19(21):1762-1764
A linearized directional coupler modulator based on electrooptic polymer was fabricated and tested. The linearity was obtained by tailoring the coupling coefficient of the device using the photobleaching technique. A two-tone test of the device was presented and it demonstrated an enhancement in intermodulation distortion compared to a Mach-Zehnder modulator. 相似文献
997.
J. T. Anderson C. L. Munsee C. M. Hung T. M. Phung G. S. Herman D. C. Johnson J. F. Wager D. A. Keszler 《Advanced functional materials》2007,17(13):2117-2124
New thin‐film dielectrics and nanolaminates have been synthesized via aqueous‐solution deposition of Hf and Zr sulfates, where facile gelation and vitrification of the precursor solution have been achieved without organic additives. X‐ray reflectivity, imaging, and metal‐insulator‐metal capacitor performance reveal that smooth, atomically dense films are readily produced by spin coating and modest thermal treatment (T < 325 °C). Dielectric characteristics include permittivities covering the range of 9–12 with breakdown fields up to 6 MV cm–1. Performance as gate dielectrics is demonstrated in field‐effect transistors exhibiting small gate‐leakage currents and qualitatively ideal device performance. The low‐temperature processing, uniformity, and pore‐free nature of the films have also allowed construction of unique, high‐resolution nanolaminates exhibiting individual layers as thin as 3 nm. 相似文献
998.
Yen F. Y. Hung C. L. Hou Y. T. Hsu P. F. Chang V. S. Lim P. S. Yao L. G. Jiang J. C. Lin H. J. Chen C. C. Jin Y. Jang S. M. Tao H. J. Chen S. C. Liang M. S. 《Electron Device Letters, IEEE》2007,28(3):201-203
This letter reports the engineering of effective work function (EWF) for tantalum carbide (TaC) metal gate on high-k gate dielectrics. The dependence of EWF on Si concentration in HfSiO as well as nitridation techniques is revealed. The EWF was extracted by both terraced oxide and terraced high-k techniques with the bulk and interface charges taken into account. The incorporation of Si in Hf-based dielectrics results in an increase of EWF, while the presence of N tends to decrease the EWF. Plasma nitridation is found to be more effective in lowering the EWF than a thermal nitridation. The phenomena can be explained by the modification of TaC/high-k interface dipole moment, which arises from the electronegativity difference for various interface bonds. Based on the above findings, we proposed a novel approach to reduce the EWF of TaC on HfSiON by using a thin HfO2 cap layer after optimizing the nitridation. The MOSFET results show that this technique is able to achieve a lower Vt without degrading the device performance 相似文献
999.
Jiau H.C. Chia Hung Kao Kuo-Feng Ssu 《IEEE transactions on pattern analysis and machine intelligence》2004,30(10):707
When studying [T.C. Oliveira et al. (2004)], we found an error and some ambiguous parts. In this paper, we state those errors. 相似文献
1000.
Integral variable structure control of nonlinear system using a CMAC neural network learning approach. 总被引:2,自引:0,他引:2
Chin-Pao Hung 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2004,34(1):702-709
This work presents a novel integral variable structure control (IVSC) that combines a cerebellar model articulation controller (CMAC) neural network and a soft supervisor controller for use in designing single-input single-output (SISO) nonlinear system. Based on the Lyapunov theorem, the soft supervisor controller is designed to guarantee the global stability of the system. The CMAC neural network is used to perform the equivalent control on IVSC, using a real-time learning algorithm. The proposed IVSC control scheme alleviates the dependency on system parameters and eliminates the chattering of the control signal through an efficient learning scheme. The CMAC-based IVSC (CIVSC) scheme is proven to be globally stable inasmuch all signals involved are bounded and the tracking error converges to zero. A numerical simulation demonstrates the effectiveness and robustness of the proposed controller. 相似文献