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91.
We present a graph theoretical methodology that reduces the implementation complexity of the multiplication of a constant vector and a scalar. The complexity of implementation is defined as the required amount of computations like additions. The proposed approach is called minimally redundant parallel (MRP) optimization and is mainly presented in a finite impulse response (FIR) filtering framework to obtain a low-complexity multiplierless implementation. The key idea is to expand the design space using shift inclusive differential coefficients (SIDCs) together with computation reordering using a graph theoretic approach to obtain maximal computation sharing. The problem is formulated using a graph in which vertices and edges represent coefficients and computational cost (number of resources). The multiplierless solution is obtained by solving a set cover problem on the vertices in the graph. A simple polynomial run time algorithm based on a greedy approach is presented. The proposed approach is compared with common-subexpression elimination to show slightly better results and is combined with it for further reduction of complexity. Simulation results show that 50-60% complexity reduction is achieved by only applying the MRP algorithm, and 70% complexity reduction is obtainable by combining it with common-subexpression elimination under a delay constraint of two or three.  相似文献   
92.
Affective Learning — A Manifesto   总被引:3,自引:0,他引:3  
The use of the computer as a model, metaphor, and modelling tool has tended to privilege the 'cognitive' over the 'affective' by engendering theories in which thinking and learning are viewed as information processing and affect is ignored or marginalised. In the last decade there has been an accelerated flow of findings in multiple disciplines supporting a view of affect as complexly intertwined with cognition in guiding rational behaviour, memory retrieval, decision-making, creativity, and more. It is time to redress the imbalance by developing theories and technologies in which affect and cognition are appropriately integrated with one another. This paper describes work in that direction at the MIT Media Lab and projects a large perspective of new research in which computer technology is used to redress the imbalance that was caused (or, at least, accentuated) by the computer itself.  相似文献   
93.
Plasma nitridation of thermally grown oxide films has proven to be an excellent gate dielectric in meeting the electrical requirements of the 65 nm node. As the 65 nm device performance is very sensitive to both physical thickness and nitrogen dose of these dielectric films, it is highly desirable to predict the electrical properties of such films. We present a simple physical model to forecast the capacitance-equivalent thickness (CET) of nMOS devices for 65 nm technology. The model is based on the total nitrogen dose and the dielectric physical thickness, both given by in-line X-ray photoelectron spectroscopy (XPS) measurement of the plasma nitrided gate dielectric. This model uses an estimated gate oxide dielectric constant, the gate depletion capacitance and the inversion layer capacitance. A good correlation is obtained between calculated and measured CET for plasma nitrided oxides from 19 to 30 Å CET and for a large range of incorporated nitrogen doses.  相似文献   
94.
An unmanned aerial vehicle (UAV)-assisted communication is a promising technique for enabling ground users in a non-functional area (NFA) or disaster area to communicate. All the base stations in the disaster area may be partially or fully damaged due to the natural calamity. Device-to-device (D2D) communication can be a viable solution for immediate connection between users in an NFA. We propose a UAV-assisted multi-hop D2D communication following a hybrid power-time switching (PTS) in this paper. Moreover, a D2D user of a cluster can communicate with another D2D user in a different cluster through UAVs. However, D2D users can harvest energy from their respective ad hoc energy stations and forward the information to the nearby D2D user following a hybrid PTS-based strategy. We propose a time frame for the same and show a node-based energy harvesting strategy. The expressions of outage probability, throughput, end-to-end energy consumption, and energy efficiency are developed for the Rician and Nakagami-m faded channel. The impact of several network parameters such as energy harvesting factor, energy harvesting efficiency, and fading parameter on the network performance is also indicated.  相似文献   
95.
EEG complexity as a measure of depth of anesthesia for patients   总被引:22,自引:0,他引:22  
A new approach for quantifying the relationship between brain activity patterns and depth of anesthesia (DOA) is presented by analyzing the spatio-temporal patterns in the electroencephalogram (EEG) using Lempel-Ziv complexity analysis. Twenty-seven patients undergoing vascular surgery were studied under general anesthesia with sevoflurane, isoflurane, propofol, or desflurane. The EEG was recorded continuously during the procedure and patients' anesthesia states were assessed according to the responsiveness component of the observer's assessment of alertness/sedation (OAA/S) score. An OAA/S score of zero or one was considered asleep and two or greater was considered awake. Complexity of the EEG was quantitatively estimated by the measure C(n), whose performance in discriminating awake and asleep states was analyzed by statistics for different anesthetic techniques and different patient populations. Compared with other measures, such as approximate entropy, spectral entropy, and median frequency, C(n) not only demonstrates better performance (93% accuracy) across all of the patients, but also is an easier algorithm to implement for real-time use. The study shows that C(n) is a very useful and promising EEG-derived parameter for characterizing the (DOA) under clinical situations.  相似文献   
96.
The evolution from analog to integrated services digital network (ISDN) telecommunication services at Tenneco Gas and the features of its telephone system are described. The results of implementing ISDN in data operations are examined. The benefits of ISDN for Tenneco are briefly summarized  相似文献   
97.
This paper presents a programmable digital finite-impulse response (FIR) filter for high-performance and low-power applications. The architecture is based on a computation sharing multiplier (CSHM) which specifically targets computation re-use in vector-scalar products and can be effectively used in the low-complexity programmable FIR filter design. Efficient circuit-level techniques, namely a new carry-select adder and conditional capture flip-flop (CCFF), are also used to further improve power and performance. A 10-tap programmable FIR filter was implemented and fabricated in CMOS 0.25-/spl mu/m technology based on the proposed architectural and circuit-level techniques. The chip's core contains approximately 130 K transistors and occupies 9.93 mm/sup 2/ area.  相似文献   
98.
Capacitances in a double-barrier tunneling structure are calculated for the specific sequential electron tunneling regime. Starting from Luryi's (1988) definition of quantum capacitance, the authors model the charge accumulation in the well during the tunneling process using the Fermi-Dirac distribution. Analytical formulas for the total capacitance and conductance are derived. A complete small-signal model is proposed that demonstrates the external capacitance and conductance of the structure and its frequency behavior. The authors show both theoretically and experimentally that the capacitance in a tunneling structure is both bias- and frequency-dependent  相似文献   
99.
Introducing Machine-to-Machine (M2M) communications over traditional 4G cellular networks make the cellular random access channel more congested and collision-prone. In order to resolve this random access congestion, we propose RoBiN - Random access using Border router in M2M cellular Networks. RoBiN proposes an architectural modification of introducing small cells, called Border Routers (BR), in cellular networks, with complete frequency reuse capability. We formulate the aforementioned challenge in terms of collision probability and system capacity. Subsequently, we propose an efficient solution for M2M communications in cellular networks. Exhaustive mathematical analysis shows that RoBiN significantly improves the random access success probability, by 50 % over existing 4G cellular systems. Simulation results on typical 4G networks corroborate our mathematical analysis and demonstrate almost 15 dB increase in Signal-to-Interference-plus-Noise Ratio (SINR) and 3 times throughput improvements over legacy 4G cellular systems. Furthermore, RoBiN also achieves 50 %?80 % improvement in collision probability over existing time alignment matching work.  相似文献   
100.
A novel image reconstruction algorithm has been developed and demonstrated for fluorescence-enhanced frequency-domain photon migration (FDPM) tomography from measurements of area illumination with modulated excitation light and area collection of emitted fluorescence light using a gain modulated image-intensified charge-coupled device (ICCD) camera. The image reconstruction problem was formulated as a nonlinear least-squares-type simple bounds constrained optimization problem based upon the penalty/modified barrier function (PMBF) method and the coupled diffusion equations. The simple bounds constraints are included in the objective function of the PMBF method and the gradient-based truncated Newton method with trust region is used to minimize the function for the large-scale problem (39919 unknowns, 2973 measurements). Three-dimensional (3-D) images of fluorescence absorption coefficients were reconstructed using the algorithm from experimental reflectance measurements under conditions of perfect and imperfect distribution of fluorophore within a single target. To our knowledge, this is the first time that targets have been reconstructed in three-dimensions from reflectance measurements with a clinically relevant phantom.  相似文献   
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