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Volume 12 No. 6
20 June 2007

2007, 12(6): 629-637.   doi:10.1016/S1007-0214(07)70167-0
Abstract ( 125 )  ( 22 )   Save
This paper presents an algorithm for identifying desirable multiple targets in an intracellular regulation network. The algorithm is based on constrained state feedback and Monte-Carlo simulations. The computational complexity of the algorithm increases linearly with increasing the number of species in a gene regulation system. An estimate is derived for the confidence level of the predicted minimum required perturbation strength when targets are prescribed a priori. The algorithm has b...

2007, 12(6): 638-646.   doi:10.1016/S1007-0214(07)70168-2
Abstract ( 109 )  ( 53 )   Save
This paper describes a semi-supervised regularized method for additive logistic regression. The graph regularization term of the combined functions is added to the original cost functional used in AdaBoost. This term constrains the learned function to be smooth on a graph. Then the gradient solution is computed with the advantage that the regularization parameter can be adaptively selected. Finally, the function step-size of each iteration can be computed using Newton-Raphson iteration. Experime...

2007, 12(6): 647-651.   doi:10.1016/S1007-0214(07)70169-4
Abstract ( 117 )  ( 30 )   Save
Dynamic airspace management plans and assigns airspace resources to airspace users on demand to increase airspace capacity. Although many studies of air traffic flow management (ATFM) have sought to optimally allocate air traffic to get the best use of given airspace resources, few studies have focused on how to build an efficient air traffic network or how to adjust the current network in real time. This paper presents an integer program model named the dynamic air route open-close problem (DRO...

2007, 12(6): 652-657.   doi:10.1016/S1007-0214(07)70170-0
Abstract ( 143 )  ( 40 )   Save
The paper analyzes the problem of blind source separation (BSS) based on the nonlinear principal component analysis (NPCA) criterion. An adaptive strong tracking filter (STF) based algorithm was developed, which is immune to system model mismatches. Simulations demonstrate that the algorithm converges quickly and has satisfactory steady-state accuracy. The Kalman filtering algorithm and the recursive least-squares type algorithm are shown to be special cases of the STF algorithm. Since the forge...

2007, 12(6): 658-662.   doi:10.1016/S1007-0214(07)70171-2
Abstract ( 164 )  ( 55 )   Save
This paper describes a channel estimation and equalization algorithm using three-layer artificial neural networks (ANNs) with feedback for multiple input multiple output wireless communication systems. An ANN structure with feedback was designed to use different learning algorithms in the different ANN layers. This actually forms a Turbo iteration process between the different algorithms which effectively improves the estimation performance of the channel equalizer. Simulation results show that ...

2007, 12(6): 663-668.   doi:10.1016/S1007-0214(07)70172-4
Abstract ( 121 )  ( 53 )   Save
A multiuser detector was developed for fast fading code-division multiple-access systems by representing the channels as a system with the multiplicative noise (SMN) model and then using the known optimal filtering algorithm for the SMN for multiuser detection (MUD). This multiuser detector allows the channel response to be stochastic in one symbol duration, which can be regarded as an effective method of MUD for fast fading CDMA systems. Performance analyses show that the multiuser detector is ...

2007, 12(6): 669-673.   doi:10.1016/S1007-0214(07)70173-6
Abstract ( 191 )  ( 26 )   Save
The problem of approximate joint diagonalization of a set of matrices is instrumental in numerous statistical signal processing applications. This paper describes a relative gradient non-orthogonal approximate joint diagonalization (AJD) algorithm based on a non-least squares AJD criterion and a special AJD using a non-square diagonalizing matrix and an AJD method for ill-conditioned matrices. Simulation results demonstrate the better performance of the relative gradient AJD algorithm compared w...

2007, 12(6): 674-677.   doi:10.1016/S1007-0214(07)70174-8
Abstract ( 254 )  ( 32 )   Save
In orthogonal frequency-division multiplexing (OFDM) systems, the carrier frequency offset (CFO) destroys the orthogonality among subcarriers which degrades system performance. Various CFO estimation methods have been developed to compensate for the CFO at the receiver. This paper describes a novel minimum output variance method for OFDM systems with CFO in additive white Gaussian noise channels. This method utilizes the phase and the amplitude of the received signal and reduces the mean square ...

2007, 12(6): 678-683.   doi:10.1016/S1007-0214(07)70175-X
Abstract ( 200 )  ( 57 )   Save
Orthogonal frequency-division multiplexing (OFDM) systems are sensitive to carrier frequency offset (CFO) which introduces intercarrier interference and significantly degrades system performance. This paper describes an iterative blind receiver consisting of a sequential Monte Carlo detector, a CFO estimator, and a compensator to reduce intercarrier interference. The framework is of low complexity due to the separation of tasks in a joint detection problem. In addition, the CFO estimator utilize...

2007, 12(6): 684-690.   doi:10.1016/S1007-0214(07)70176-1
Abstract ( 143 )  ( 20 )   Save
Concurrent programs written in a machine level language are being used in many areas but verification of such programs brings new challenges to the programming language community. Most of the studies in the literature on verifying the safety properties of concurrent programs are for high-level languages, specifications, or calculi. Therefore, more studies are needed on concurrency verification for machine level language programs. This paper describes a framework of a Petri net based safety polic...

2007, 12(6): 691-699.   doi:10.1016/S1007-0214(07)70177-3
Abstract ( 142 )  ( 49 )   Save
Token protocol provides a new coherence framework for shared-memory multiprocessor systems. It avoids indirections of directory protocols for common cache-to-cache transfer misses, and achieves higher interconnect bandwidth and lower interconnect latency compared with snooping protocols. However, the broadcasting increases network traffic, limiting the scalability of token protocol. This paper describes an efficient technique to reduce the token protocol network traffic, called sharing relation ...

Software Support for LIRAC Architecture

2007, 12(6): 700-706.   doi:10.1016/S1007-0214(07)70178-5
Abstract ( 122 )  ( 26 )   Save
Software Support for LIRAC Architecture

2007, 12(6): 707-713.   doi:10.1016/S1007-0214(07)70179-7
Abstract ( 149 )  ( 26 )   Save
Context-awareness enhances human-centric, intelligent behavior in a smart environment; however, context-awareness is not widely used due to the lack of effective infrastructure to support context-aware applications. This paper presents an agent-based middleware for providing context-aware services for smart spaces to afford effective support for context acquisition, representation, interpretation, and utilization to applications. The middleware uses a formal context model, which combines first o...

2007, 12(6): 714-718.   doi:10.1016/S1007-0214(07)70180-3
Abstract ( 132 )  ( 35 )   Save
Video structure analysis is a basic requirement for most content-based video editing and processing systems. This paper presents a fast video structure analysis method based on image segmentation in each frame, with region matching between frames. The structure analysis decomposes the video into several moving objects, including information about their colors, positions, shapes, movements, and lifetimes. The method also supports user interactions to improve the results. The result shows that thi...

2007, 12(6): 719-728.   doi:10.1016/S1007-0214(07)70181-5
Abstract ( 194 )  ( 56 )   Save
Parallel frequent pattern discovery algorithms exploit parallel and distributed computing resources to relieve the sequential bottlenecks of current frequent pattern mining (FPM) algorithms. Thus, parallel FPM algorithms achieve better scalability and performance, so they are attracting much attention in the data mining research community. This paper presents a comprehensive survey of the state-of-the-art parallel and distributed frequent pattern mining algorithms with more emphasis on pattern d...

2007, 12(6): 729-740.   doi:10.1016/S1007-0214(07)70182-7
Abstract ( 199 )  ( 22 )   Save
One of the difficulties that goal-oriented requirements analyses encounters is that the efficiency of the goal refinement is based on the analysts’ subjective knowledge and experience. To improve the efficiency of the requirements elicitation process, engineers need approaches with more systemized analysis techniques. This paper integrates the goal-oriented requirements language i* with concepts from a structured problem analysis notation, problem frames (PF). The PF approach anal...

2007, 12(6): 741-746.   doi:10.1016/S1007-0214(07)70183-9
Abstract ( 163 )  ( 18 )   Save
A 4 Mb embedded silicon-oxide-nitride-oxide-silicon (SONOS) memory was developed with a 0.18 μm CMOS logic compatible technology. A reverse programming array architecture was proposed to reduce the chip area, enhance the operating window, and increase the read speed. The charge distribution was analyzed to optimize the programming and erase conditions considering both the operating speed and the endurance performance. The final test chip has a good endurance of 105 cycles and a data r...

2007, 12(6): 747-751.   doi:10.1016/S1007-0214(07)70184-0
Abstract ( 149 )  ( 24 )   Save
The paper describes the growth of a germanium (Ge) film on a thin relaxed Ge-rich SiGe buffer. The thin Ge-rich SiGe buffer layer was achieved through a combination of ultrahigh vacuum chemical vapor deposition (UHVCVD) SiGe epitaxial growth and SiGe oxidation. A lower Ge content strained SiGe layer was first grown on the Si (001) substrate and then the Ge mole fraction was increased by oxidation. After removal of the surface oxide, a higher Ge content SiGe layer was grown and oxidized again. Th...

2007, 12(6): 752-756.   doi:10.1016/S1007-0214(07)70185-2
Abstract ( 189 )  ( 32 )   Save
Transmission lines (T-Lines) are widely used in millimeter wave applications on silicon-based complementary metal-oxide semiconductor (CMOS) technology. Accurate modeling of T-lines to capture the related electrical effects has, therefore, become increasingly important. This paper describes a method to model the capacitance and conductance of T-Lines on CMOS multilayer, lossy substrates based on conformal mapping, and region subdivision. Tests show that the line parameters (per unit length) obta...

2007, 12(6): 757-760.   doi:10.1016/S1007-0214(07)70186-4
Abstract ( 238 )  ( 24 )   Save
An ultrashort 10-GHz pulse generation scheme was successfully demonstrated using a bulk material InGaAsP electroabsorption modulator to generate the seed pulse. A self-phase modulation-based reshaper was used after the adiabatic soliton compression in a comb-like dispersion profiled fiber. Experiments and simulations confirm that the reshaper effectively removes the pulse pedestal and improves the pulse extinction ratio. As a result, the 10-GHz pulse had no pedestal, a high extinction ratio, and...