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ABSTRACT: The joint linear transceiver design for Multiple-Input Multiple-Output (MIMO) adhoc cognitive radio networks when the channel state information (CSI) is uncertain is discussed in this paper. The uncertainty in CSI is modeled using Stochastic Error (SE) and Norm Bounded Error (NBE) models. The Sum-Mean Square Error (SMSE) performance is used to formulate the design problem. To optimize the network, the transmit power budget for secondary user transmitters and the maximum allowed interference at primary user receivers are constrained. In the design methodology, the network parameters are optimized to best serve the users when the worst possible channel realizations occur. It is shown that for the SE model of uncertainty, this problem can be cast as a Second Order Cone Problem (SOCP), while for the NBE model, the problem becomes a Semi-Definite Program (SDP). These two problems are solved efficiently using the numerical solver packages YALMIP and SDPT3. Finally simulation results are presented to evaluate the performance of the proposed methods.
IEEE Transactions on Wireless Communications 06/2011; · 2.59 Impact Factor
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ABSTRACT: We report, for the first time to our knowledge, an optically powered wavelength-division-multiplexing (WDM) communication system with distributed parametric amplification in the dispersion-shifted fiber. The parametric pump for the amplification of WDM signals also acts as the power supply for the receiver component. The proposed scheme is also a potential candidate for the “last mile” transmission. Successful musical signal transmission has been demonstrated. Additionally, four channels of 10-Gb/s WDM signals are used to get more precise performance evaluation of the system. The power penalties of less than or equal to 1.35 dB at a bit-error rate of $10^{-9}$ are achieved for all WDM channels in the presence of 10-dB parametric gain.
IEEE Photonics Technology Letters 09/2010; · 2.19 Impact Factor
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ABSTRACT: Power system information integration requires for the realization of open access,? data sharing and data combination among all kinds of application systems. As a standard transmission format, XML provides methods for describing structural data, has capability of data self-description and is independent of platform. These characteristics are fit for information exchange in power system. According to the current applications in power system, the isomeric data types in power automation application systems are analyzed and classified by different causes. Taking video monitoring system as example, the paper focuses on principles and methods for information exchange in power system using XML techniques. The characteristics of data modeling are firstly analyzed and the principles of data modeling are illustrated. According to practical power automation system and properties of XML, the potential applications in information exchange of power system are proposed. As a pivot, the principles of data exchange among different types of database are elaborated in detail, and then the implementation methods and examples XML are presented. Based on SQL server database and IIS server, the implement methods and application characteristics are elaborated and analyzed.
Advances in Power System Control, Operation and Management (APSCOM 2009), 8th International Conference on; 12/2009
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ABSTRACT: GaN nanorods with a wurtzite/zinc-blende (WZ/ZB) heterostructure are synthesized by chemical vapor deposition. They have a triangular cross section and grow along the WZ [01 1 0] direction. The WZ and ZB phases appear alternately along the nanorod’s transverse direction, forming a type-II superlattice structure. Two ultraviolet emission peaks dominate the photoluminescence spectra of the GaN nanorods. One originates from excitonic transitions within the WZ regions. The other shows an anomalous “S-shaped” energy shift with increasing temperature, and is attributed to radiative recombinations of carriers localized at potential fluctuations in ZB regions. The carrier localization also results in high luminescent efficiency of the GaN nanorods.
Applied Physics Letters 10/2009; · 3.84 Impact Factor
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ABSTRACT: A low-complexity detection scheme consisting of a sphere decoder and a parallel interference cancellation (PIC) equaliser is proposed for OFDM systems in doubly-selective fading channels. Theoretical analysis and simulation results show that this detection scheme substantially improves the symbol error rate performance of OFDM systems compared with the traditional PIC equaliser while requiring lower complexity at moderate and high signal-to-noise ratios.
Electronics Letters 08/2009; · 0.96 Impact Factor
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ABSTRACT: Nonlinear problem of maneuvering target is a hot and difficult topic in radar target tracking fielding. In this paper, we firstly introduces several mainstream non-linear filtering methods in tracking fielding, then, pay more attention to analyses the uncertainty sampling method, random sampling method and Markov chain Monte Carlo algorithms, and with its improving methods by introducing reversible jump ratio. we present a comprehensive picture to see the performance by comparing among classical tracking methods combining with RJMCMC method, which include the PF, EKF-PF, UKF-PF techniques from other literature that have seen wide application in Radar target tracking field. Simulations on maneuvering target radar tracking are carried out to validate the performance of the proposed scheme.
Information and Automation, 2009. ICIA '09. International Conference on; 07/2009
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B. Greene,
Q. Liang,
K. Amarnath,
Y. Wang,
J. Schaeffer,
M. Cai, Y. Liang,
S. Saroop,
J. Cheng,
A. Rotondaro, [......],
D. Ioannou,
E. Wu,
M. Chudzik,
D.-G. Park,
D. Brown,
S. Luning,
D. Mocuta,
E. Maciejewski,
K. Henson,
E. Leobandung
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ABSTRACT: This work presents a 32 nm SOI CMOS technology featuring high-k/metal gate and an SRAM cell size of 0.149 mum<sup>2</sup>. V<sub>min</sub> operation down to 0.6 V in a 16 Mb SRAM array test vehicle has been demonstrated. Aggressive ground rules are achieved with 193 nm immersion lithography. High performance is enabled by high-k/metal gate plus innovation on strained silicon elements including embedded SiGe and dual stress liner (DSL). Gate lengths down to 25 nm have been demonstrated enabling performance without the power penalty from gate capacitance. AC drive currents of 1.55 mA/um and 1.22 mA/um have been achieved at an off-state of 100 nA/mum and V<sub>DD</sub> of 1 V for NFET and PFET, respectively. For the first time, we have also demonstrated that SOI maintains performance benefit over bulk silicon in high-k/metal gate and 32 nm ground rules.
VLSI Technology, 2009 Symposium on; 07/2009
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K. Henson,
H. Bu,
M.H. Na, Y. Liang,
U. Kwon,
S. Krishnan,
J. Schaeffer,
R. Jha,
N. Moumen,
R. Carter, [......],
R. Knarr,
T. Bailey,
B. Zhang,
K. Wong,
T. Graves-Abe,
E. Luckowski,
D.-G. Park,
V. Narayanan,
M. Chudzik,
M. Khare
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ABSTRACT: CMOS devices with high-k/metal gate stacks have been fabricated using a gate-first process flow and conventional stressors at gate lengths of 25 nm, highlighting the scalability of this approach for high performance SOI CMOS technology. AC drive currents of 1630muA/mum and 1190muA/mum have been demonstrated in 45 nm ground-rules at 1V and 200nA/mum off current for nFETs and pFETs, at a Tinv of 14 and 15 respectively. The drive currents were achieved using a simplified high-k/metal gate integration scheme with embedded SiGe and dual stress liners (DSL) and without utilizing additional stress enhancers. Devices have been fabricated with Tinv's down to 12 and 10.5 demonstrating the scalability of this approach for 32 nm and beyond.
Electron Devices Meeting, 2008. IEDM 2008. IEEE International; 01/2009
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P. De Dobbelaere,
B. Analui,
E. Balmater,
D. Guckenberger,
M. Harrison,
R. Koumans,
D. Kucharski, Y. Liang,
G. Masini,
A. Mekis, [......],
V. Sadagopan,
S. Sahni,
T.J. Sleboda,
Y. Wang,
B. Welch,
J. Witzens,
J. Yao,
S. Abdalla,
S. Gloeckner,
G. Capellini
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ABSTRACT: For the first time we demonstrate a fully self-contained photonic transceiver system on a single die with monolithically integrated Ge photo-detectors. The transceiver allows error-free bidirectional 4times10 Gb/s WDM transmission using a single CMOS die at each end of the link.
Optical Communication, 2008. ECOC 2008. 34th European Conference on; 10/2008
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T. Pinguet,
B. Analui,
E. Balmater,
D. Guckenberger,
M. Harrison,
R. Koumans,
D. Kucharski, Y. Liang,
G. Masini,
A. Mekis, [......],
T.J. Sleboda,
D. Song,
Y. Wang,
B. Welch,
J. Witzens,
J. Yao,
S. Abdalla,
S. Gloeckner,
P. De Dobbelaere,
G. Capellini
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ABSTRACT: We demonstrate monolithically integrated 4times10 Gb/s WDM transceivers built in a production 130 nm SOI CMOS process. Only light sources are external to the chip. 40 Gb/s error-free, bidirectional transmission is demonstrated.
Group IV Photonics, 2008 5th IEEE International Conference on; 10/2008
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ABSTRACT: Constructions of gene and protein dynamic network is a challenging and important problem in genomic research while estimating the temporal correlations and non-stationarity are the keys in this process. In this paper, we develop Bayesian dynamic multivariate models to tackle this challenge for inferring the gene network profiles associated with diseases and treatments. We treat both the stochastic transition matrix and the observation matrix time-variant and include temporal correlation structures in the covariance matrix estimations in the multivariate Bayesian setting. The unevenly spaced short time courses with unseen time points are treated as hidden state variables. Bayesian approaches with various prior and hyper-prior models with MCMC algorithms are used to estimate the model parameters. We apply our models to multiple tissue polygenetic affymetrix data sets. Preliminary results show that the genomic dynamic behavior can be well captured by the proposed model
Engineering in Medicine and Biology Society, 2006. EMBS '06. 28th Annual International Conference of the IEEE; 10/2006
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ABSTRACT: In this study, we propose a method to estimate arterial wall strain using intravascular ultrasound (IVUS) images. The method is based on a nonrigid image registration algorithm, which represents the displacement field by cubic B-splines, and incorporates smoothness and incompressibility constraints. The 2D displacement field is then used to calculate the local strain tensors. With the 2D strain tensors, both radial and circumferential strain distributions can be obtained, and color-coded for display. The algorithm has been evaluated with synthetic motion IVUS images and phantom IVUS images under two luminal pressures
Engineering in Medicine and Biology Society, 2006. EMBS '06. 28th Annual International Conference of the IEEE; 10/2006
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ABSTRACT: Because channel estimation can play a crucial role on coherent detection of the information symbols in each data block, this paper proposes a redundant precoding assisted blind channel estimation approach for orthogonal frequency-division multiplexing (OFDM) systems. A redundant linear frequency-domain precoder is applied on each pair of blocks before they enter the OFDM system. Due to the introduced structure, the frequency-selective channel can be identified at the receiver based on auto-correlation operations, singular value decomposition (SVD) and resolving the scalar ambiguity. The proposed channel estimation method has low computational complexity and requires no prior statistical information of channel or noise. And the proposed blind method has high spectral efficiency owing to exploiting no training sequence. Computer simulations confirm that this proposed blind channel estimation method can identify the frequency-selective channels perfectly and have a good performance
Signal Processing, 2006 8th International Conference on; 02/2006
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Proceedings of the IASTED International Conference on Intelligent Systems and Control; 01/2006
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J. Wang,
C. W. Domier,
Z. G. Xia, Y. Liang,
N. C. Luhmann,
H. Park,
T. Munsat,
E. Mazzucato,
M. J. van de Pol,
I. G. J. Classen,
A. J. H. Donne
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ABSTRACT: A two-dimensional electron cyclotron emission imaging (ECEI) diagnostic has been developed in which broad bandwidth radiation is collected by a vertically aligned mixer array and separated by frequency band. Using a 16 element array, and an 8 band receiver attached to each array element, time-resolved 16×8 images of electron temperature profiles and fluctuations of the TEXTOR plasma are acquired with vertical and horizontal channel spacings of 11 and 8 mm , and spot sizes of 13 and 9 mm , respectively. The system is wideband tunable from 95 to 130 GHz , and the focus location may be shifted horizontally via translation of one of the optical imaging elements. System design and laboratory testing details of the ECE Imaging optics and multichannel wideband electronics are presented, together with TEXTOR plasma data.
Review of Scientific Instruments 11/2004; · 1.37 Impact Factor
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M Nicolaou,
Y Q Song,
C A Sato,
A Orlacchio,
T Kawarai,
H Medeiros, Y Liang,
S Sorbi,
E Richard,
E I Rogaev,
Y Moliaka,
A C Bruni,
R Jorge,
M Percy,
R Duara,
L A Farrer,
P St Georg-Hyslop,
E A Rogaeva
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ABSTRACT: Amyloid beta-peptide (Abeta) plays a central role in the pathogenesis of Alzheimer's disease (AD). The gene encoding the beta-site APP cleaving enzyme (BACE), one of two enzymes that sequentially cleave the beta-amyloid precursor protein to generate Abeta, has recently been cloned. We tested the hypothesis that BACE might be genetically associated with AD by linkage analysis (56 pedigrees), by direct nucleotide sequencing of the entire open reading frame (20 subjects with familial AD, and 10 subjects with sporadic AD) and by allelic association analysis (155 AD cases and 173 non-demented controls). Our results revealed no evidence for either genetic linkage or allelic association between BACE and AD, and no coding sequence mutations were detected in the open reading frame of the BACE gene. These data suggest that while BACE protein plays an important role in the pathogenesis of AD, and may be a robust therapeutic target, it is unlikely to be a major AD susceptibility locus.
Neurogenetics 11/2001; 3(4):203-6. · 3.35 Impact Factor
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E A Rogaeva,
K C Fafel,
Y Q Song,
H Medeiros,
C Sato, Y Liang,
E Richard,
E I Rogaev,
P Frommelt,
A D Sadovnick,
W Meschino,
K Rockwood,
M A Boss,
R Mayeux,
P St George-Hyslop
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ABSTRACT: Mutations in the presenilin-1 gene (PS1) account for a majority of patients with early-onset familial AD. However, the clinical indications and algorithms for genetic testing in dementia are still evolving.
The entire open reading frame of the PS1 gene was sequenced in a series of 414 consecutive patients referred for diagnostic testing, including 372 patients with AD and 42 asymptomatic persons with a strong family history of AD.
Forty-eight independent patients screened had a PS1 mutation including 21 novel mutations. In addition, 3% of subjects (11/413) had a known polymorphism, the Glu318Gly substitution. The majority of the mutations were missense substitutions but there were three insertions and Delta exon 10 mutation. With six exceptions (codons 35, 178, 352, 354, 358, and 365) most of the mutations occurred at residues conserved in the homologous PS2 gene or in PS1 of other species.
Eleven percent of a referral-based series of patients with AD can be explained by coding sequence mutations in the PS1 gene. The high frequency of PS1 mutations in this study indicates that screening for PS1 mutations in AD is likely to be successful, especially when directed at patients with a positive family history with onset before 60 years (90% of those with PS1 mutations were affected by age 60 years). This will also have significance for the secondary identification of at-risk relatives who might be candidates for future prophylactic therapies for AD.
Neurology 09/2001; 57(4):621-5. · 8.31 Impact Factor
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M. Nicolaou,
Y.-Q. Song,
C. Sato,
A. Orlacchio,
T. Kawarai,
H. Medeiros, Y. Liang,
S. Sorbi,
E. Richard,
E. Rogaev,
Y. Moliaka,
A. Bruni,
R. Jorge,
M. Percy,
R. Duara,
L. Farrer,
P. St George-Hyslop,
E. Rogaeva
[show abstract]
[hide abstract]
ABSTRACT: Amyloid β-peptide (Aβ) plays a central role in the pathogenesis of Alzheimer's disease (AD). The gene encoding the β-site
APP cleaving enzyme (BACE), one of two enzymes that sequentially cleave the β-amyloid precursor protein to generate Aβ, has
recently been cloned. We tested the hypothesis that BACE might be genetically associated with AD by linkage analysis (56 pedigrees),
by direct nucleotide sequencing of the entire open reading frame (20 subjects with familial AD, and 10 subjects with sporadic
AD) and by allelic association analysis (155 AD cases and 173 non-demented controls). Our results revealed no evidence for
either genetic linkage or allelic association between BACE and AD, and no coding sequence mutations were detected in the open
reading frame of the BACE gene. These data suggest that while BACE protein plays an important role in the pathogenesis of
AD, and may be a robust therapeutic target, it is unlikely to be a major AD susceptibility locus.
Neurogenetics 01/2001; 3(4):203-206. · 3.35 Impact Factor
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G Devi,
A Fotiou,
D Jyrinji,
B Tycko,
S DeArmand,
E Rogaeva,
Y Q Song,
H Medieros, Y Liang,
A Orlacchio,
J Williamson,
P St George-Hyslop,
R Mayeux
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ABSTRACT: Two children of an adult with early-onset, autopsy-confirmed Alzheimer disease (AD) developed dementia in their late 20s and were subsequently found to have novel mutations in codon 434 of the presenilin 1 (PS1) gene on chromosome 14, a G-to-T substitution at nucleotide 1548 and a C-to-G substitution at nucleotide 1549. The younger of the 2 children had AD confirmed at postmortem examination. The disease course in these 3 individuals was characterized by cognitive and behavioral problems accompanied by myoclonus, seizures, and aphasia within 5 years after onset. Two grandparents had clinically diagnosed AD with stroke beginning at ages 78 and 66 years, but neither had a PS1 mutation. No other living family member was demented, nor did any other family member have the PS1 mutation. We conclude that the affected parent of the proband was a likely recent founder for these novel mutations in PS1. The family demonstrates the clinical and genetic heterogeneity of AD. Arch Neurol. 2000;57:1454-1457
Archives of Neurology 11/2000; 57(10):1454-7. · 7.58 Impact Factor
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G Yu,
M Nishimura,
S Arawaka,
D Levitan,
L Zhang,
A Tandon,
Y Q Song,
E Rogaeva,
F Chen,
T Kawarai, [......],
E Rogaev,
M Smith,
C Janus,
Y Zhang,
R Aebersold,
L S Farrer,
S Sorbi,
A Bruni,
P Fraser,
P St George-Hyslop
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ABSTRACT: Nicastrin, a transmembrane glycoprotein, forms high molecular weight complexes with presenilin 1 and presenilin 2. Suppression of nicastrin expression in Caenorhabditis elegans embryos induces a subset of notch/glp-1 phenotypes similar to those induced by simultaneous null mutations in both presenilin homologues of C. elegans (sel-12 and hop-1). Nicastrin also binds carboxy-terminal derivatives of beta-amyloid precursor protein (betaAPP), and modulates the production of the amyloid beta-peptide (A beta) from these derivatives. Missense mutations in a conserved hydrophilic domain of nicastrin increase A beta42 and A beta40 peptide secretion. Deletions in this domain inhibit A beta production. Nicastrin and presenilins are therefore likely to be functional components of a multimeric complex necessary for the intramembranous proteolysis of proteins such as Notch/GLP-1 and betaAPP.
Nature 10/2000; 407(6800):48-54. · 36.28 Impact Factor
