Browsing by Author "Huang, HC"

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A new pseudo-bipolar-junction-transistor (PBJT) and its application in the design of retinal smoothing network
(2002)
Wu, CY
;
Huang, HC
;
Lin, LJ
;
Huang, KH
;
電機學院
A new MOSFET circuit structure called the pseudo-BJT (PBJT) is proposed and analyzed in this work. This new structure mimics the function of the BJT, and it has advantages of smaller area and better process compatibility over the real BJT. The function of PBJT is verified to be similar to the real BJT via HSPICE simulation. Moreover, applications of the retinal smoothing network and the edge-extracting circuit using the PBJT structure are also demonstrated. The PBJT plays the role of the real BJT in both applications, and they are verified to be functionally correct via HSPICE simulations.
A queue manager chip for shared buffer ATM switches
(1996-11-01)
Lin, YS
;
Huang, HC
;
Shung, CB
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This paper presents an efficient queue manager chip for controlling a 16 x 16 shared buffer ATM switch with a 256-cell buffer. Compared to conventional implementations of queue managers for shared buffer ATM switches, our design eliminates the idle address FIFO and the pre-allocated bubbles at the tails of output queues. The former reduces the storage size required for queue management, while the latter improves the effective buffer capacity. Such modular implementation also provides flexibilities in queue management implementation. Backpressure with soft-full and hard-full flow control for multi-stage expansion and two priority classes with push-out cell discarding are supported without extra hardware overhead. This chip was designed and fabricated using 0.8 mu m CMOS technology. It has 35,700 transistors in a chip area of 28.3 mm(2), with a core of 10.4 mm(2) and 31,960 transistors. Two test sequences were developed during the design phase to fully verify the queue management functions of the prototype chip. The queue manager chip was tested up to 36 MHz, and is able to control a 16 x 16 shared buffer switch with a 155 MHz link rate.
A queue manager chip for shared buffer ATM switches
(1996-11-01)
Lin, YS
;
Huang, HC
;
Shung, CB
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This paper presents an efficient queue manager chip for controlling a 16 x 16 shared buffer ATM switch with a 256-cell buffer. Compared to conventional implementations of queue managers for shared buffer ATM switches, our design eliminates the idle address FIFO and the pre-allocated bubbles at the tails of output queues. The former reduces the storage size required for queue management, while the latter improves the effective buffer capacity. Such modular implementation also provides flexibilities in queue management implementation. Backpressure with soft-full and hard-full flow control for multi-stage expansion and two priority classes with push-out cell discarding are supported without extra hardware overhead. This chip was designed and fabricated using 0.8 mu m CMOS technology. It has 35,700 transistors in a chip area of 28.3 mm(2), with a core of 10.4 mm(2) and 31,960 transistors. Two test sequences were developed during the design phase to fully verify the queue management functions of the prototype chip. The queue manager chip was tested up to 36 MHz, and is able to control a 16 x 16 shared buffer switch with a 155 MHz link rate.
A robust fine granularity scalability using trellis-based predictive leak
(2002-06-01)
Huang, HC
;
Wang, CN
;
Chiang, TH
;
資訊科學與工程研究所
;
電子工程學系及電子研究所
Recently, the MPEG-4 committee has approved the MPEG-4 fine granularity scalability (FGS) profile as a streaming video tool. In this paper, we propose novel techniques to further improve the temporal prediction at the enhancement layer so that coding efficiency is superior to the existing FGS. Our approach utilizes two parameters, the number of bitplanes beta (0 less than or equal to beta less than or equal to maximal number of bitplanes) and the amount of predictive leak alpha (0 less than or equal to alpha less than or equal to 1), to control the construction of the reference frame at the enhancement layer. These parameters alpha and beta can be selected for each frame to provide tradeoffs between coding efficiency and error drift. Our approach offers a general and flexible framework that allows further optimization. It also includes several well-known motion-compensated FGS techniques as special cases with particular sets of alpha and beta. We analyze the theoretical advantages when parameters alpha and beta are used, and provide an adaptive technique to select alpha and beta, which yields an improved performance as compared to that of fixed parameters. An identical technique is applied to the base layer for further improvement. Our experimental results show over 4 dB improvements in coding efficiency using the MPEG-4 testing conditions. The removal of error propagation is demonstrated with several typical channel transmission scenarios.
A tabu search based maximum descent algorithm for VQ codebook design
(2001-09-01)
Huang, HC
;
Chu, SC
;
Pan, JS
;
Lu, ZM
;
電子工程學系及電子研究所
A maximum descent (MD) method has been proposed for vector quantization (VQ) codebook design. Compared with the traditional generalized Lloyd algorithm (GLA), the MD algorithm achieves better codebook performance with far less computation time. However, searching for the optimal partitioning hyperplane of a multidimensional cluster is a difficult problem in the MD algorithm. Three partition techniques have been proposed for the MD method in the literature. In this paper, a new partition technique based on the tabu search (TS) approach is presented for the MD algorithm. Experimental results show that the tabu search based MD algorithm can produce a better codebook than can the conventional MD algorithms.
A VQ-based robust multi-watermarking algorithm
(2002-07-01)
Huang, HC
;
Wang, FH
;
Pan, JS
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
New methods for digital image watermarking based on the characteristics of vector quantization (VQ) are proposed. In contrast with conventional watermark embedding algorithms to embed only one watermark at a time into the original source; we present one algorithm to embed multiple watermarks for copyright protection. The embedding and extraction processes are efficient for implementing with conventional VQ techniques; and they can be accomplished in parallel to shorten the processing time. After embedding, embedder would output one watermarked reconstruction image and several secret keys associated with the embedded watermarks. These secret keys are then registered to the third party to preserve the ownership of the original source in order to prevent the attackers from inserting counterfeit watermarks. Simulation results show that under no attacks, the embedded watermarks could be perfectly extracted. If there are some intentional attacks in our simulation, all the watermarks could survive to protect the copyrights. Therefore, we are able to claim the robustness, usefulness, and ease of implementation of our algorithm.
Adaptive symmetric mean filter: A new noise-reduction approach based on the slope facet model
(2001-10-10)
Huang, HC
;
Chen, CM
;
Wang, SD
;
Lu, HHS
;
統計學研究所
Two new noise-reduction algorithms, namely, the adaptive symmetric mean filter (ASMF) and the hybrid filter, are presented in this paper. The idea of the ASMF is to find the largest symmetric region on a slope facet by incorporation of the gradient similarity criterion and the symmetry constraint into region growing. The gradient similarity criterion allows more pixels to be included for a statistically better estimation, whereas the symmetry constraint promises an unbiased estimate if the noise is completely removed. The hybrid filter combines the advantages of the ASMF, the double-window modified-trimmed mean filter, and the adaptive mean filter to optimize noise reduction on the step and the ramp edges. The experimental results have shown the ASMF and the hybrid filter are superior to three conventional filters for the synthetic and the natural images in terms of the root-mean-squared error, the root-mean-squared difference of gradient, and the visual presentation. (C) 2001 Optical Society of America.
Adaptive watermarking using relationships between wavelet coefficients
(2005)
Chen, YH
;
Su, JM
;
Fu, HC
;
Huang, HC
;
Pao, HT
In this paper, we propose an approach that hides watermarks in relationships between wavelet coefficients. This approach would minimize the perceptual distortion of watermarked images, measured with PSNR or just noticeable distortion (JND). Therefore, the strength of watermarks can be enlarged to increase the robustness of the watermarks, while keeping the quality of watermarked images visually accepted. Experimental results show that the watermark is still detectable after common image processing operations such as JPEG compression, Gaussian filtering and sharpening.
An adaptive and robust watermarking method based on VQ
(2002-04-01)
Huang, HC
;
Wang, FS
;
Pan, JS
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
An adaptive and robust watermarking algorithm based on vector quantization (VQ) is presented in this paper. A binary watermark is adaptively embedded with the characteristics of the original source in the VQ domain, then the watermarked image along with a secret key are transmitted to the receiver for protecting the ownership. In extracting the watermark, we make use of the pre-registered secret key in addition to the watermarked image to examine whether the watermark could survive the intentional attacks or not. We performed a variety of attacks on the watermarked image, including the destruction attacks and the synchronization attacks, to show the robustness and effectiveness of the proposed algorithm. After watermark extraction, we acquired the extracted watermark that is highly similar to the embedded one; in addition, the information conveyed therein is easily recognizable. Hence, the proposed algorithm is not only robust bust also useful for protecting the ownership of digital media.
An agent-based system to discover protein-protein interactions, identify protein complexes and proteins with multiple peptide mass fingerprints
(2006-07-15)
Lee, TY
;
Horng, JT
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Juan, HF
;
Huang, HD
;
Wu, LC
Proteins "work together" by actually binding to form multicomponent complexes that carry out specific functions. Proteomic analyses based on the mass spectrum are now key methods to determine the components in protein complexes. The protein-protein interaction or functional association may be known to exist among the extracted protein spots while analyzing the proteins on the 2D gel. In this study, we develop an agent-based system, namely AgentMultiProtIdent, which integrated two protein identification tools and a variety of databases storing relations among proteins and used to discover protein-protein interactions and protein functional associations, and identify protein complexes and proteins with multiple peptide mass fingerprints as input. The system takes Multiple Peptide Mass Fingerprints (PMFs) as a whole in the protein complex or protein identification. With the relations among proteins, it may greatly improve the accuracy of identification of protein complexes. Also, possible relationship of the multiple peptide mass fingerprints, such as ontology relation, can be discovered by our system, especially in the identification of protein complexes.
An embedding algorithm for multiple watermarks
(2003-03-01)
Shieh, CS
;
Huang, HC
;
Wang, FH
;
Pan, JS
;
電子工程學系及電子研究所
A new algorithm for embedding several watermarks into the same original source is proposed in this paper. Instead of conventional watermark embedding algorithms that embed one watermark in one specific domain, we propose algorithms for embedding multiple watermarks into different compression domains to protect the ownership of the original images. The proposed schemes for embedding and extraction in different domains vary from the existing methods reported in the literature. Simulation results show their robustness for surviving intentional attacks and, hence, their effectiveness in protecting copyrights. They are also easy to implement.
Appropriate sizes of porous and solid blocks for heat transfer under an impinging jet
(1997-03-01)
Fu, WS
;
Huang, HC
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交大名義發表
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機械工程學系
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National Chiao Tung University
A study of appropriate sizes of both porous and solid blocks mounted on a heated region impinged by a laminar slot jet was investigated numerically. A numerical method of SIMPLEC is adopted to solve governing equations, and a one-equation thermal model with Van Driest's wall function is considered for solving the energy equation of the porous block. The results indicated that enhancement of heat transfer is obtained for both shorter porous and solid block cases and decreasement of heat transfer occurs for longer block cases. Compared with the without block case, there exists an appropriate length of the porous block to gain the maximum thermal enhancement efficiency. As for the solid block case, as the length becomes shorter, the thermal enhancement efficiency becomes better.
Automated information. mining on multimedia TV news archives
(2005)
Lai, PS
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Cheng, SS
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Sun, SY
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Huang, TY
;
Su, JM
This paper addresses an integrated information mining techniques for multimedia TV-news archive. The utilizes techniques from the fields of acoustic, image, and video analysis, for information retrieval on news story title, newsman and scene identification. The goal is to construct a compact yet meaningful abstraction of broadcast news video, allowing users to browse through large amounts of data in a non-linear fashion with flexibility and efficiency. By using acoustic analysis, the system can classify video into news versus commercials, with 90% accuracy on a data set of 400 hours TV-news recorded off the air from July 2003 to August of 2004. By applying speaker identification and/or image detection techniques, each news stories can be segmented with an accuracy of 96%. On screen captions or subtitles are recognized by OCR techniques to produce the text title of each news stories. The extracted title words can be used to link or to navigate more related News contents on the WWW. In cooperation with facial and scene analysis and recognition techniques, OCR results can provide users with multimodality query for specific news stories. Some experimental results are presented and discussed for the system reliability and performance evaluation and comparison.
Combined encryption and watermarking approaches for scalable multimedia coding
(2004)
Chang, FC
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Huang, HC
;
Hang, HM
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Intellectual Property (IP) protection is a critical element in a multimedia transmission system. Conventional IP protection schemes can be categorized into two major branches: encryption and watermarking. In this paper, a structure to perform layered access protection by combining encryption and robust watermarking is proposed and implemented. By taking advantage of the nature of cryptographic schemes and digital watermarking, the copyright of multimedia contents can be well protected. We adopt the scalable transmission method over the broadcasting environment. The embedded watermark can be thus extracted with high confidence. Then, the next-layer secrets can be perfectly decrypted and reconstructed. Finally, the media contents are recovered.
Effects of a random porosity model on heat transfer performance of porous media
(1999-01-01)
Fu, WS
;
Huang, HC
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機械工程學系
;
Department of Mechanical Engineering
Due to the non-uniform distribution and fractural structure of the beads inside a porous medium, the porosity distributed in the porous medium is random for most realistic situations. Therefore, the effects of the porosity distributed casually inside a porous block mounted on a heated region with a laminar slot impinging jet on flow and thermal fields are investigated numerically. A numerical method of SIMPLEC is adopted to solve governing equations, as for the energy equation, a one-equation thermal model with Van Driest's wall function is adopted. AU the non-Darcian effects including the solid boundary and inertial effects are considered and three different porosity models of constant, variable and random are examined. The results indicate that the relationship between the local Nusselt number Nu(x) and the near wall local porosity epsilon(x) is a negative correlation. Consequently, in order to enhance the thermal performance of the porous medium, the porosity near the solid plate should be smaller to make the conductive heat transfer to be dominant. (C) 1998 Elsevier Science Ltd. All rights reserved.
Efficient and robust watermarking algorithm with vector quantisation
(2001-06-21)
Huang, HC
;
Wang, FH
;
Pan, JS
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
A new method for watermarking based on Vector quantisation is proposed. It is efficient for implementation with conventional techniques, and simulation results show its robustness under a variety of attacks. Tt also represents superiority over eng algorithms.
Electron energy state spin-orbit splitting in nanoscopic quantum rings
(2001)
Voskoboynikov, O
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Huang, HC
;
Shi, C
;
Lee, CP
;
電子工程學系及電子研究所
The impact of spin-orbit interaction on the electron energy states in nanoscopic semiconductor quantum dots and rings is studied theoretically. The effective one-band Hamiltonian approximation with the spin-orbit coupling potential is used. It is shown that the spin-orbit interaction can produce a considerable spin splitting of excited electronic states at zero magnetic fields. We investigated changes in the spin splitting when the geometrical structure is gradually changed from a dot-like shape to a ring-like one. It has been found that the completion of the quantum ring geometry leads to the reversing of the splitting sign. (C) 2001 Elsevier Science Ltd. All rights reserved.
Electron spin filtering in all-semiconductor tunneling structures
(2003-09-01)
Yu, L
;
Huang, HC
;
Voskoboynikov, O
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
In this work we briefly review the present day perspectives for exploiting conventional nonmagnetic semiconductor nano-technology to design high speed spin-filter devices. In recent theoretical investigations a high spin polarization has been predicted for the ballistic tunneling current in semiconductor single- and double-barrier asymmetric tunnel structures of III-V semiconductors with strong Rashba spin-orbit coupling. We show in this paper that the polarization in the tunneling can probability be sufficiently increased for producing realistic single-barrier structures by including of the Dresselhaus term into consideration. (C) 2004 Published by Elsevier Ltd.
Enhanced motion estimation for interframe wavelet video coding
(2004)
Tsai, CY
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Hsu, HK
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Huang, HC
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Hang, HM
;
Wu, GZ
An enhanced motion estimation scheme is incorporated into the interframe wavelet coding architecture in this paper. Interframe wavelet coding has the advantage of SNR, temporal, and spatial scalability, and is a potential candidate for the on-going MPEG-21 scalable video coding standard. Motion-compensated temporal Filtering (MCTF) is one of its essential components. Therefore, motion estimation plays an important role in deciding the coding performance. In this paper, we modified the motion estimation syntax/scheme originally specified in the MPEG Advanced Video Coding (AVC) and use it in the interframe wavelet structure. Besides, the techniques of I-block, bi-directional motion estimation, lambda-value adjustment and motion information partitioning are employed. Simulation results show very promising performance particularly on subjective quality.
Error control for low bit rate coding transmission
(1997)
Huang, HC
;
Hang, HM
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Video compression is an indispensable element in multimedia communications systems. We simulate the H.263 video coder and pass the compressed data through a simulated mobile communication channel. Preliminary results indicate that the error control codes, such as BCH codes, are very useful for protecting the compressed data. In addition! the error correcting capability of the lapped orthogonal transform (LOT) are also investigated.