The document proposes a GreenMST solution that uses the minimum spanning tree (MST) algorithm to calculate a loop-free topology for OpenFlow networks using the learning switch module. This prevents broadcast storms while enabling failover capabilities. The MST is recomputed dynamically in response to topology changes to open and close ports. An implementation was created using Open vSwitch and the Beacon controller that demonstrated the ability of GreenMST to efficiently compute the MST and update port statuses with changes to links or switches. Future work is proposed to integrate dynamic link costs and alternative path memorization.
Grant Reaber “Wavenet and Wavenet 2: Generating high-quality audio with neura...Lviv Startup Club
WaveNet and WaveNet 2 are neural network models that can directly generate audio waveforms from text. WaveNet produces the highest quality text-to-speech but is slow, taking minutes to generate seconds of audio. WaveNet 2 speeds this up by 3000x through a "distillation" technique that trains a faster model using the original WaveNet. Both models are autoregressive, generating each audio sample conditioned on previous samples, and can be conditioned on text to enable text-to-speech synthesis.
DUNE on current and next generation HPC PlatformsMarkus Blatt
In this talk we present the Distributed and Unified Numerics
Environment (DUNE). It is a software framework for the parallel
numerical solution of partial differential equations with grid-based
methods. Using generic programming techniques it strives for both:
high flexibility (efficiency of the programmer) and high performance
(efficiency of the program).
We present parallel applications realized with DUNE and
show their scalability on current HPC platforms such as the Blue
Gene/P system in Jülich.
Finally we will take a closer look on hardware attributes that
influence the scalability of DUNE and software solving partial
differential equations in general. We investigate how DUNE will
perform on future hardware like Blue Gene/Q.
Special emphasis will be put on the performance of parallel
iterative solvers both in general and in DUNE.
This document describes the implementation of a pipelined double precision floating point multiplier on an FPGA. It begins with background on floating point representation and implementations on FPGAs. It then describes the algorithm for floating point multiplication, which involves adding the exponents and multiplying the mantissas. The design presented in the paper divides the floating point multiplier into three pipeline stages - the first checks for zero operands, the second adds the exponents, and the third multiplies the mantissas, checks the sign, and normalizes the result. Simulation results on a Xilinx Virtex-II FPGA show that the pipelined design can produce one result per clock cycle after an initial delay.
This document summarizes a research paper that proposes an efficient VLSI implementation of a pipelined fast Fourier transform (FFT). The key aspects are:
1) A single-path delay feedback (SDF) pipeline architecture is adopted to implement the FFT processor. This architecture requires less memory space and has lower power consumption than existing designs.
2) A reconfigurable complex multiplier and bit-parallel multipliers are used instead of read-only memories to store twiddle factors. This eliminates the need for ROMs and reduces power consumption.
3) The proposed FFT architecture contains three types of processing elements - a complex constant multiplier, delay buffers, and extra units for IFFT computation. It achieves a
FIR Filter Implementation by Systolization using DA-based DecompositionIDES Editor
In this paper we present 1D and 2D systolic
Distributed Arithmetic (DA) based structures that are designed
for the implementation of Finite Impulse Response (FIR) filters.
The paper compares the 1D DA based systolic structure with
1D systolic DA based decomposition method. The filters are
implemented on a Xilinx Virtex II Pro (XC2VP30) FPGA using
HDL and system metrics like Area, Gate Count, Maximum
Usable Frequency and Power consumption are estimated for
different filter orders and address lengths. The 1D systolic
decomposition structure is also compared with the existing
system generator implementation of DA FIR.. Results for an
exemplary implementation are presented.
Cancellation of Zigbee interference in OFDM based WLAN for multipath channelIDES Editor
Zigbee is one of the major sources of interference
in 2.4GHz band for WLANs. It is seen whenever any Zigbee
system is operating near to the WLAN system and
transmitting signal at same frequency, time as of WLAN’s, the
later ones performance detoriate severely. So in this paper an
algorithm is proposed to estimate Zigbee interference
component present in all OFDM based WLANs sub-carriers
and cancel out the Zigbee interference from the received
signal of WLANs receiver for multipath fading channels in
frequency domain. Simulation results shows for high SNR
values full cancellation of Zigbee interference or zero BER is
possible.
This document summarizes a research paper presented at the 2011 American Control Conference about developing a new bilaterally teleoperated robotic vehicle platform with passivity control. The platform allows a human operator to control a remote vehicle via a steering wheel interface while receiving feedback on road surface forces. To ensure stability with time-varying communication delays, the researchers apply Power-based Time Domain Passivity Control at each side of the communication channel, which improves tracking performance and reduces operator effort. Experimental results demonstrate the effectiveness of the approach and functionality of the platform.
Grant Reaber “Wavenet and Wavenet 2: Generating high-quality audio with neura...Lviv Startup Club
WaveNet and WaveNet 2 are neural network models that can directly generate audio waveforms from text. WaveNet produces the highest quality text-to-speech but is slow, taking minutes to generate seconds of audio. WaveNet 2 speeds this up by 3000x through a "distillation" technique that trains a faster model using the original WaveNet. Both models are autoregressive, generating each audio sample conditioned on previous samples, and can be conditioned on text to enable text-to-speech synthesis.
DUNE on current and next generation HPC PlatformsMarkus Blatt
In this talk we present the Distributed and Unified Numerics
Environment (DUNE). It is a software framework for the parallel
numerical solution of partial differential equations with grid-based
methods. Using generic programming techniques it strives for both:
high flexibility (efficiency of the programmer) and high performance
(efficiency of the program).
We present parallel applications realized with DUNE and
show their scalability on current HPC platforms such as the Blue
Gene/P system in Jülich.
Finally we will take a closer look on hardware attributes that
influence the scalability of DUNE and software solving partial
differential equations in general. We investigate how DUNE will
perform on future hardware like Blue Gene/Q.
Special emphasis will be put on the performance of parallel
iterative solvers both in general and in DUNE.
This document describes the implementation of a pipelined double precision floating point multiplier on an FPGA. It begins with background on floating point representation and implementations on FPGAs. It then describes the algorithm for floating point multiplication, which involves adding the exponents and multiplying the mantissas. The design presented in the paper divides the floating point multiplier into three pipeline stages - the first checks for zero operands, the second adds the exponents, and the third multiplies the mantissas, checks the sign, and normalizes the result. Simulation results on a Xilinx Virtex-II FPGA show that the pipelined design can produce one result per clock cycle after an initial delay.
This document summarizes a research paper that proposes an efficient VLSI implementation of a pipelined fast Fourier transform (FFT). The key aspects are:
1) A single-path delay feedback (SDF) pipeline architecture is adopted to implement the FFT processor. This architecture requires less memory space and has lower power consumption than existing designs.
2) A reconfigurable complex multiplier and bit-parallel multipliers are used instead of read-only memories to store twiddle factors. This eliminates the need for ROMs and reduces power consumption.
3) The proposed FFT architecture contains three types of processing elements - a complex constant multiplier, delay buffers, and extra units for IFFT computation. It achieves a
FIR Filter Implementation by Systolization using DA-based DecompositionIDES Editor
In this paper we present 1D and 2D systolic
Distributed Arithmetic (DA) based structures that are designed
for the implementation of Finite Impulse Response (FIR) filters.
The paper compares the 1D DA based systolic structure with
1D systolic DA based decomposition method. The filters are
implemented on a Xilinx Virtex II Pro (XC2VP30) FPGA using
HDL and system metrics like Area, Gate Count, Maximum
Usable Frequency and Power consumption are estimated for
different filter orders and address lengths. The 1D systolic
decomposition structure is also compared with the existing
system generator implementation of DA FIR.. Results for an
exemplary implementation are presented.
Cancellation of Zigbee interference in OFDM based WLAN for multipath channelIDES Editor
Zigbee is one of the major sources of interference
in 2.4GHz band for WLANs. It is seen whenever any Zigbee
system is operating near to the WLAN system and
transmitting signal at same frequency, time as of WLAN’s, the
later ones performance detoriate severely. So in this paper an
algorithm is proposed to estimate Zigbee interference
component present in all OFDM based WLANs sub-carriers
and cancel out the Zigbee interference from the received
signal of WLANs receiver for multipath fading channels in
frequency domain. Simulation results shows for high SNR
values full cancellation of Zigbee interference or zero BER is
possible.
This document summarizes a research paper presented at the 2011 American Control Conference about developing a new bilaterally teleoperated robotic vehicle platform with passivity control. The platform allows a human operator to control a remote vehicle via a steering wheel interface while receiving feedback on road surface forces. To ensure stability with time-varying communication delays, the researchers apply Power-based Time Domain Passivity Control at each side of the communication channel, which improves tracking performance and reduces operator effort. Experimental results demonstrate the effectiveness of the approach and functionality of the platform.
On the Performance Analysis of Multi-antenna Relaying System over Rayleigh Fa...IDES Editor
In this work, the end-to-end performance of an
amplify-and-forward multi-antenna infrastructure-based relay
(fixed relay) system over flat Rayleigh fading channel is
investigated. New closed form expressions for the statistics of
the received signal-to-noise ratio (SNR) are presented and
applied for studying the outage probability and the average
bit error rate of the digital receivers. The results reveal that
the system performance improves significantly (roughly 3 dB)
for M=2 over that for M=1 in both low and high signal-tonoise
ratio. However, little additional performance
improvement can be achieved for M>2 relative to M=2 at high
SNR.
Image Compression using Combined Approach of EZW and LZWIJERA Editor
Image Processing is most popular and widely used technique. In this paper we had proposed a technique for image compression. Here the user can return the processed image to the original image without any loss. In this proposed technique the test images are processed through the image compression algorithm. Here we apply combined approach of EZW and LZW. This technique is implemented on different types of images like .bmp, .tiff,.dcm (medical images),binary images. Performance of the proposed technique can be evaluated compared to LBG techniques by the parameters like PSNR, Compression ratio and MSE
This document discusses a modified coding technique to reduce peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) systems. It begins by introducing the PAPR problem in OFDM and existing solutions using Golay complementary sequences (GCS). It then presents definitions and theorems regarding recursive Golay complementary codes (RGCC) that can provide codewords with low PAPR. The paper proposes generating a 16-QAM OFDM signal from QPSK Golay complementary pairs using RGCC to achieve both higher coding rate and lower PAPR compared to existing techniques.
Research Inventy : International Journal of Engineering and Scienceresearchinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
JUS 2011 - Thermalhydraulic coupling using ICoCo : an Interface for Code Coup...OpenCascade
The document discusses ICoCo, an interface for coupling codes and the SALOME platform. ICoCo was developed to address the need for a flexible interface to couple thermalhydraulic codes with different time step and data exchange algorithms. It uses a supervisor architecture, with codes accessed through C++ classes that implement a common interface. This allows codes to be coupled and exchanged more easily, and coupling algorithms to be specified outside of the codes themselves. ICoCo has been implemented in several thermalhydraulic codes and its API approach is proving useful, though continued improvements are still needed.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Using Many-Core Processors to Improve the Performance of Space Computing Plat...Fisnik Kraja
This document summarizes a presentation on introducing many-core and commercial off-the-shelf (COTS) technologies into satellite computing architectures. It discusses constraints of onboard computers like power, size, heat, and high reliability requirements. It proposes a new architecture using many-core processors and COTS products to improve processing abilities while maintaining reliability through hardware and software fault tolerance techniques. It evaluates the architecture on synthetic aperture radar benchmarking and finds performance scales linearly with cores. Combining COTS with radiation-hardened components could provide over 100x speedup and improved reliability, flexibility, and portability.
This document discusses polyphase filters and their applications. It begins with an introduction to polyphase filters and how they are used for decimation and interpolation in digital signal processing applications. Next, it describes active and passive polyphase filter implementations and their advantages. Finally, it discusses some example applications of polyphase filters, including predistortion for linearization of nonlinear systems and nonlinear echo cancellation using Volterra filters.
This document summarizes issues related to medium access control (MAC) protocols for wireless ad hoc networks. It discusses common MAC protocols like ALOHA, Slotted ALOHA, CSMA, and their variants. It also covers protocols specific to wireless networks like MACA, MACAW, and CSMA/CA. Additional topics covered include Bluetooth, wireless mesh networks, mobile ad hoc networks, and wireless sensor networks. Simulation tools for modeling wireless ad hoc networks are also mentioned.
The document summarizes research on using Run Length Encoding (RLE) to reduce Peak-to-Average Power Ratio (PAPR) in Orthogonal Frequency Division Multiplexing (OFDM) systems. Simulation results showed that RLE reduced PAPR by about 3 dB at a probability of 10-2 while maintaining a compression ratio of 1.7. The symbol error rate performance in additive white Gaussian noise and Rayleigh fading channels was unchanged with RLE. Thus, RLE is an effective PAPR reduction technique that does not degrade system performance.
This paper proposes an algorithm to optimize the trade-off between space and time for a class of electronic structure calculations involving tensor contractions. The algorithm starts with an operation-based representation and applies transformations to minimize the total memory requirement by reducing the size of intermediate arrays through loop fusion techniques. This approach addresses the challenge of large temporary memory requirements for coupled cluster and other electronic structure models.
Utp pds_l4_procesamiento de señales del habla con mat_labjcbenitezp
This lab explores speech signal processing using MATLAB sound functions. Students will work in teams of two and submit a lab report and audio files. The lab involves using MATLAB functions to read and write .wav files and manipulate speech signals by speeding up or slowing down playback time without changing pitch through butt splicing segments. Experiments include loading a recorded .wav file into MATLAB, verifying playback at different sample rates, playing matrices, and butt splicing to halve or double playback time while maintaining pitch. Results will be analyzed using spectrograms and a demo for the instructor.
Diametrical Mesh of Tree (D2D-MoT) Architecture: A Novel Routing Solution for...IDES Editor
Network-on-chip (NoC) is a new aspect for designing
of future System-On-Chips (SoC) where a vast number of IP
cores are connected through interconnection network. The
communication between the nodes occurred by routing packets
rather than wires. It supports high degree of scalability,
reusability and parallelism in communication. In this paper,
we present a Mesh routing architecture, which is called
Diametrical 2D Mesh of Tree, based on Mesh-of-Tree (MoT)
routing and Diametrical 2D Mesh. It has the advantage of
having small diameter as well as large bisection width and
small node degree clubbed with being the fastest network in
terms of speed. The routing algorithm ensures that the packets
will always reach from source to sink through shortest path
and is deadlock free.
This document summarizes Laurent Leyssenne's thesis on the design of reconfigurable radiofrequency power amplifiers for wireless applications. The thesis aims to develop novel adaptive power amplifier architectures using silicon to improve battery life. It explores two families of adaptive mechanisms: discretized power amplifiers and adaptive bias power amplifiers. For discretized power amplifiers, it investigates architectures based on power stage bypass and parallel switched power cells to allow fast reconfiguration over a wide power range with low distortion. The switched power cell approach digitizes the envelope signal and uses control bits to dynamically modulate Volterra kernels, with quantization noise requiring oversampling and resolution techniques.
Ber performance analysis of mimo systems using equalizationAlexander Decker
The document discusses equalization techniques for analyzing bit error rate (BER) performance in multiple-input multiple-output (MIMO) systems. It analyzes different equalization techniques like zero forcing (ZF), minimum mean squared error (MMSE), ZF with successive interference cancellation (ZF-SIC), MMSE with SIC (MMSE-SIC), maximum likelihood (ML) and sphere decoding. Simulation results show that successive interference methods outperform ZF and MMSE, but have higher complexity. ML provides better performance than others, while sphere decoding gives the best performance but highest complexity compared to ML.
This document discusses back propagation networks and soft computing. It provides an overview of back propagation networks, including what they are, their basic structure with an input, hidden and output layer, and how they learn through examples using backpropagation. It also discusses topics that will be covered in lectures on back propagation networks, including background information, the backpropagation learning algorithm, and a numerical example. The document provides details on computation in the input, hidden and output layers of a multi-layer feedforward backpropagation network.
This chapter describes how to configure spanning tree on Catalyst enterprise LAN switches. It discusses understanding how spanning tree works, including electing the root switch, creating the spanning tree topology, and default and example configurations. Spanning tree provides path redundancy while preventing undesirable loops in the network.
This document summarizes a research paper that presents an area efficient 128-point Fast Fourier Transform (FFT) processor using a mixed radix 4-2 computation for OFDM applications. The processor uses a cached-memory architecture with two single-port SRAMs to increase FFT execution time. It was designed using a 0.35um CMOS process and integrates 552,000 transistors within an area of 2.8x2.8mm2. The processor can perform a 128-point, 36-bit FFT in 23.2us for 1D and 23.8ms for 2D FFT at 133MHz clock speed.
The document proposes a modified 5-stage pipelined MIPS processor architecture to reduce dynamic power consumption. Unnecessary transitions during unused pipeline stages consume extra power. The proposed architecture reduces these transitions by bypassing unused stages, such as bypassing the memory access stage for arithmetic instructions. It includes instruction and data memory, register file with dual write ports, datapath, control unit, forwarding unit, and hazard detection. Verilog modeling and synthesis shows the proposed design operates at 193.98MHz with 26.5% lower power compared to a single write-port pipeline.
This document provides an overview of the H.264 video compression standard. It describes the standard's basic concepts and important features/algorithms in detail. Compared to previous standards, H.264 achieves coding improvements of at least 2 dB in PSNR and 40% bit rate savings. The standard supports various block sizes, motion compensation, transform coding, quantization, entropy coding, and flexible slice ordering to improve compression performance.
This document summarizes an energy efficient home that utilizes solar, wind, and rainwater collection systems. The home was designed with energy star construction including optimal orientation, insulation, windows, and appliances. It generates electricity through a hybrid solar/wind system and heats water solarly. These green features reduced the home's electricity usage by 60% and gas by 40% compared to a typical home. The renewable systems were estimated to increase the home's building costs by $8.18 per square foot.
On the Performance Analysis of Multi-antenna Relaying System over Rayleigh Fa...IDES Editor
In this work, the end-to-end performance of an
amplify-and-forward multi-antenna infrastructure-based relay
(fixed relay) system over flat Rayleigh fading channel is
investigated. New closed form expressions for the statistics of
the received signal-to-noise ratio (SNR) are presented and
applied for studying the outage probability and the average
bit error rate of the digital receivers. The results reveal that
the system performance improves significantly (roughly 3 dB)
for M=2 over that for M=1 in both low and high signal-tonoise
ratio. However, little additional performance
improvement can be achieved for M>2 relative to M=2 at high
SNR.
Image Compression using Combined Approach of EZW and LZWIJERA Editor
Image Processing is most popular and widely used technique. In this paper we had proposed a technique for image compression. Here the user can return the processed image to the original image without any loss. In this proposed technique the test images are processed through the image compression algorithm. Here we apply combined approach of EZW and LZW. This technique is implemented on different types of images like .bmp, .tiff,.dcm (medical images),binary images. Performance of the proposed technique can be evaluated compared to LBG techniques by the parameters like PSNR, Compression ratio and MSE
This document discusses a modified coding technique to reduce peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) systems. It begins by introducing the PAPR problem in OFDM and existing solutions using Golay complementary sequences (GCS). It then presents definitions and theorems regarding recursive Golay complementary codes (RGCC) that can provide codewords with low PAPR. The paper proposes generating a 16-QAM OFDM signal from QPSK Golay complementary pairs using RGCC to achieve both higher coding rate and lower PAPR compared to existing techniques.
Research Inventy : International Journal of Engineering and Scienceresearchinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
JUS 2011 - Thermalhydraulic coupling using ICoCo : an Interface for Code Coup...OpenCascade
The document discusses ICoCo, an interface for coupling codes and the SALOME platform. ICoCo was developed to address the need for a flexible interface to couple thermalhydraulic codes with different time step and data exchange algorithms. It uses a supervisor architecture, with codes accessed through C++ classes that implement a common interface. This allows codes to be coupled and exchanged more easily, and coupling algorithms to be specified outside of the codes themselves. ICoCo has been implemented in several thermalhydraulic codes and its API approach is proving useful, though continued improvements are still needed.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Using Many-Core Processors to Improve the Performance of Space Computing Plat...Fisnik Kraja
This document summarizes a presentation on introducing many-core and commercial off-the-shelf (COTS) technologies into satellite computing architectures. It discusses constraints of onboard computers like power, size, heat, and high reliability requirements. It proposes a new architecture using many-core processors and COTS products to improve processing abilities while maintaining reliability through hardware and software fault tolerance techniques. It evaluates the architecture on synthetic aperture radar benchmarking and finds performance scales linearly with cores. Combining COTS with radiation-hardened components could provide over 100x speedup and improved reliability, flexibility, and portability.
This document discusses polyphase filters and their applications. It begins with an introduction to polyphase filters and how they are used for decimation and interpolation in digital signal processing applications. Next, it describes active and passive polyphase filter implementations and their advantages. Finally, it discusses some example applications of polyphase filters, including predistortion for linearization of nonlinear systems and nonlinear echo cancellation using Volterra filters.
This document summarizes issues related to medium access control (MAC) protocols for wireless ad hoc networks. It discusses common MAC protocols like ALOHA, Slotted ALOHA, CSMA, and their variants. It also covers protocols specific to wireless networks like MACA, MACAW, and CSMA/CA. Additional topics covered include Bluetooth, wireless mesh networks, mobile ad hoc networks, and wireless sensor networks. Simulation tools for modeling wireless ad hoc networks are also mentioned.
The document summarizes research on using Run Length Encoding (RLE) to reduce Peak-to-Average Power Ratio (PAPR) in Orthogonal Frequency Division Multiplexing (OFDM) systems. Simulation results showed that RLE reduced PAPR by about 3 dB at a probability of 10-2 while maintaining a compression ratio of 1.7. The symbol error rate performance in additive white Gaussian noise and Rayleigh fading channels was unchanged with RLE. Thus, RLE is an effective PAPR reduction technique that does not degrade system performance.
This paper proposes an algorithm to optimize the trade-off between space and time for a class of electronic structure calculations involving tensor contractions. The algorithm starts with an operation-based representation and applies transformations to minimize the total memory requirement by reducing the size of intermediate arrays through loop fusion techniques. This approach addresses the challenge of large temporary memory requirements for coupled cluster and other electronic structure models.
Utp pds_l4_procesamiento de señales del habla con mat_labjcbenitezp
This lab explores speech signal processing using MATLAB sound functions. Students will work in teams of two and submit a lab report and audio files. The lab involves using MATLAB functions to read and write .wav files and manipulate speech signals by speeding up or slowing down playback time without changing pitch through butt splicing segments. Experiments include loading a recorded .wav file into MATLAB, verifying playback at different sample rates, playing matrices, and butt splicing to halve or double playback time while maintaining pitch. Results will be analyzed using spectrograms and a demo for the instructor.
Diametrical Mesh of Tree (D2D-MoT) Architecture: A Novel Routing Solution for...IDES Editor
Network-on-chip (NoC) is a new aspect for designing
of future System-On-Chips (SoC) where a vast number of IP
cores are connected through interconnection network. The
communication between the nodes occurred by routing packets
rather than wires. It supports high degree of scalability,
reusability and parallelism in communication. In this paper,
we present a Mesh routing architecture, which is called
Diametrical 2D Mesh of Tree, based on Mesh-of-Tree (MoT)
routing and Diametrical 2D Mesh. It has the advantage of
having small diameter as well as large bisection width and
small node degree clubbed with being the fastest network in
terms of speed. The routing algorithm ensures that the packets
will always reach from source to sink through shortest path
and is deadlock free.
This document summarizes Laurent Leyssenne's thesis on the design of reconfigurable radiofrequency power amplifiers for wireless applications. The thesis aims to develop novel adaptive power amplifier architectures using silicon to improve battery life. It explores two families of adaptive mechanisms: discretized power amplifiers and adaptive bias power amplifiers. For discretized power amplifiers, it investigates architectures based on power stage bypass and parallel switched power cells to allow fast reconfiguration over a wide power range with low distortion. The switched power cell approach digitizes the envelope signal and uses control bits to dynamically modulate Volterra kernels, with quantization noise requiring oversampling and resolution techniques.
Ber performance analysis of mimo systems using equalizationAlexander Decker
The document discusses equalization techniques for analyzing bit error rate (BER) performance in multiple-input multiple-output (MIMO) systems. It analyzes different equalization techniques like zero forcing (ZF), minimum mean squared error (MMSE), ZF with successive interference cancellation (ZF-SIC), MMSE with SIC (MMSE-SIC), maximum likelihood (ML) and sphere decoding. Simulation results show that successive interference methods outperform ZF and MMSE, but have higher complexity. ML provides better performance than others, while sphere decoding gives the best performance but highest complexity compared to ML.
This document discusses back propagation networks and soft computing. It provides an overview of back propagation networks, including what they are, their basic structure with an input, hidden and output layer, and how they learn through examples using backpropagation. It also discusses topics that will be covered in lectures on back propagation networks, including background information, the backpropagation learning algorithm, and a numerical example. The document provides details on computation in the input, hidden and output layers of a multi-layer feedforward backpropagation network.
This chapter describes how to configure spanning tree on Catalyst enterprise LAN switches. It discusses understanding how spanning tree works, including electing the root switch, creating the spanning tree topology, and default and example configurations. Spanning tree provides path redundancy while preventing undesirable loops in the network.
This document summarizes a research paper that presents an area efficient 128-point Fast Fourier Transform (FFT) processor using a mixed radix 4-2 computation for OFDM applications. The processor uses a cached-memory architecture with two single-port SRAMs to increase FFT execution time. It was designed using a 0.35um CMOS process and integrates 552,000 transistors within an area of 2.8x2.8mm2. The processor can perform a 128-point, 36-bit FFT in 23.2us for 1D and 23.8ms for 2D FFT at 133MHz clock speed.
The document proposes a modified 5-stage pipelined MIPS processor architecture to reduce dynamic power consumption. Unnecessary transitions during unused pipeline stages consume extra power. The proposed architecture reduces these transitions by bypassing unused stages, such as bypassing the memory access stage for arithmetic instructions. It includes instruction and data memory, register file with dual write ports, datapath, control unit, forwarding unit, and hazard detection. Verilog modeling and synthesis shows the proposed design operates at 193.98MHz with 26.5% lower power compared to a single write-port pipeline.
This document provides an overview of the H.264 video compression standard. It describes the standard's basic concepts and important features/algorithms in detail. Compared to previous standards, H.264 achieves coding improvements of at least 2 dB in PSNR and 40% bit rate savings. The standard supports various block sizes, motion compensation, transform coding, quantization, entropy coding, and flexible slice ordering to improve compression performance.
This document summarizes an energy efficient home that utilizes solar, wind, and rainwater collection systems. The home was designed with energy star construction including optimal orientation, insulation, windows, and appliances. It generates electricity through a hybrid solar/wind system and heats water solarly. These green features reduced the home's electricity usage by 60% and gas by 40% compared to a typical home. The renewable systems were estimated to increase the home's building costs by $8.18 per square foot.
The document provides tips for environmental responsibility, including reducing waste and energy and water consumption. It recommends choosing recycled products, using recycling bins properly, and fixing leaky taps or toilets to save water. It also suggests turning off lights and electronics when not in use, using public transport or cycling instead of cars, and lowering the thermostat to reduce heating bills and save energy. Failing to adopt these practices could lead to depletion of resources and increased pollution over the long run.
The document describes the Punjab Mandi Bhawan in Mohali, designed by architect Sarbjit Singh Bahga. The building serves as the new headquarters for the Punjab State Agricultural Marketing Board. Bahga employed several energy-efficient design strategies, including orienting the building along a north-south axis to maximize natural light, minimizing solar heat gain through vertical louvers and overhangs, and using high-performance glass and building materials. The six-floor building emphasizes natural lighting and includes skylights over a central atrium. Bahga's design achieved the client's goals of a modern, efficient office building that demonstrates innovative energy-efficient architecture.
This energy efficient home utilizes various appliances and design features to minimize energy usage. It has 10 rooms, venetian blinds for air flow control, and energy efficient LED lights, appliances, and electronics that operate at far less wattage than regular items. A daily schedule and power limitations help ensure overages do not exceed allotments.
Landscape architecture energy efficient landscape lecture 8Bineet Chhajer
Tree consumes lesser water, cleans air pollution, provide shade and require low maintenance. Start Plant and Design with Native Tree to save our future.
The French school in Damascus, Syria follows a sustainable design approach using passive strategies to minimize energy costs. The campus houses 900 students through small classroom buildings arranged around courtyards. Natural ventilation is prioritized using solar chimneys, earth ducts, and nighttime cooling to maintain thermal comfort without air conditioning. Thick, insulated walls provide thermal mass to moderate indoor temperatures. Shaded courtyards and vegetation create microclimates connecting outdoor and indoor learning spaces.
The document provides tips for making a home more energy efficient and environmentally friendly. It recommends using renewable energy sources like solar power and rain water harvesting. It also suggests starting with simple steps like switching to energy efficient light bulbs, pressure cookers, and other eco-friendly appliances. Some conscious decisions and changes in habits can make a difference, such as turning down the thermostat, switching appliances off standby mode, and turning off lights when leaving a room. Maintaining radiators and washing full loads can help. Mending dripping taps and cutting down on shower time are also crucial. The overall message is to start making these changes today to help save the earth.
The document discusses various energy efficiency and renewable energy sources. It covers improving energy efficiency, types of solar, water, wind, and biomass energy. Geothermal energy and hydrogen fuel are also examined. Decentralized micropower systems are presented as an emerging trend that utilizes various renewable energy sources at a local level. The importance of a sustainable energy strategy and transitioning to renewable sources is emphasized.
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Energy Efficiency Methods And Techniques V.2patmcmmc
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I came to know regarding this competition from rediff.com
The idea of Energy Efficient design is
to modulate the conditions such that they
are always within or as close as possible to
comfort zone.Modulations introduced by the
landscape,built form,envelope,materials and
other control measures bring the conditions
within the range throughout twenty four hours
cycle.
This is goal of Energy Efficient Architecture
Buildings, as they are designed and used today, contribute to serious environmental and economical problems because of excessive consumption of energy and other natural resources. The close connection between energy use in buildings and environmental damage arises because energy-intensive and monetarily expensive solutions sought to construct a building and meet its demands for heating, cooling, ventilation, and lighting cause severe depletion of invaluable environmental resources
Energy resource efficiency in new constructions
can be effected by adopting an
Integrated Approach To Building Design.
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[JPDC,JCC@LMN22] Ad hoc systems Management and specification with distributed...
Power point
1. Energy efficent MST in
OpenFlow networks
European Workshop on Software Defined Network
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
2. OUTLINE
Motivation: OF, LearningSwitch module and loops
The proposed solution
Implementation and the virtual test-bed
Measurements and validation
Future works and conclusions
2
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
3. Fact 1: OpenFlow and modules
OpenFlow is growing protocol with great potentials
Powerful but still too complex
Users experience difficulties in the use of modules
The routing module is difficult and tricky
Powerful...
...but it requires in-depth knowledge of topology, devices,
cluster, ...
The learning Switch is easier than Routing module. Useful to:
Experiment the power of the protocol (rules, actions, ...)
Build and integrate new modules
3
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
4. Fact 2:
OpenFlow and loop free technologies
Fail-over mechanisms require topologies with physical loops
Without loop-free technologies broadcast storms
ARP requests, any broadcast or multicast based protocol, ...
“Common” L2 switches use the Spanning Tree Protocol
Software OF switches should export the STP_bit, but most of
them DON’T!
Problem:
Lack of a loop free technology using OF learning switch module
4
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
5. From a need to the idea
Need
LearningSwitch + looped topologies + non-STP switches
Simple Plug&Play solution for beginners
Idea
Build the Minimum Spanning Tree of the network
Turn off ports outside MST
Goal
Prevent broadcast storm
Offer failover mechanisms
Save energy 5
L. Prete, F . Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
6. GreenMST: how it works
Link between switches changes: linkUpdate event
After each topology change recalculate Minimum Spanning Tree
MST is computed using the Kruskal algorithm
Ports status is modified
Open ports not included in the MST are closed
Closed ports included in the MST are opened
6
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
7. GreenMST: the proposed solution
Modular approach
Topology keeps the switch map updated and it sends updates to the Green
MST module when a link changes
Green MST computes the new MST using current topology information and it
sends ModPort actions to the switches
LearningSwitch module continues to work normally, sending packets only
through the opened ports
7
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
8. MST computation and Change Set
Saved 3-2 closed
Ports status saved in a data structure
Minimization of ModPort commands to the switches
8
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
9. Implementation: the virtual testbed
OF out-of-band
network
Users’ network
Goal: experiment OpenFlow features and potentialities 9
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
10. Implementation: Software used
OpenvSwitch Beacon controller
Enterprise Java
functionalities Multi-platform
Used by different Thread-oriented
+
hypervisors, es.
Xen
Used in large testbed
(>150 switch)
Modular
10
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
11. Experiment 1 – ARP request
MST module
is loaded (t = 37,4s)
Redundant ARP requests
disappear (t = 37,76s)
From the point of view of OVS01 (one of the switches) after a PING
[t0 - t(37,3)] => observation window without MST module
t(37,4) => MST module is loaded
t(37,76) => redundant ARP requests disappear
Final MST + ModPort actions end after 0,36 sec
11
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
12. Experiment 2 – switch activation
A B C D
From the point of view of the controller
t0 => GreenMST module is loaded and MST is calculated
=> No switches are active
tA,B,C,D => Switches are activated
=> MST is re-calculated and ports status is modified (except for
OVS01)
12
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
13. Experiment 3 – Link status change
A B
From the point of view of the controller
t0 => Network is stable and MST is already calculated
tA => Link between OVS03 and OVS04 is deactivated
New MST calculated in 7 ms
tB => Link between OVS03 and OVS04 is re-activated
New MST calculated in 9 ms 13
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
14. Conclusions and future works
Now
Enable loop free technologies and failover mechanisms for
Learning Switch OF modules
As well if the devices do not support the STP technology!
Save energy turning dynamically off the unused ports of the
switches
In the future
Assign dynamically a cost to the links between the switches
using link parameters (bandwidth, delay, jitter)
...but also SNMP or passive flow monitoring protocols (Netflow, sFlow, ...)
Memorize the alternative paths between two nodes before a fail
After a fail the alternative path is chosen
Integration with the Routing module
14
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
15. THANK YOU
Question
Get the code
https://github.com/LucaPrete/GreenMST
15
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
16. Reference
Project page: https://github.com/LucaPrete/GreenMST
OpenFlow official site: http://www.openflow.org
Open vSwitch: http://www.openvswitch.org
Controller
Beacon: https://openflow.stanford.edu/display/Beacon/Home
16
L. Prete, F. Farina, M. Campanella, A. Biancini
Darmstadt, 26th Oct 2012
Editor's Notes
Let’s talk about facts FIRST FACT: OpenFlow is a hype and growing protocol with great potentials its powerful consists of the infinite possibilities that it gives, but this also makes it so complex for users, that have to mix competences of programming and network engineering The so called routing is one of the two basic modules that allow the forwarding of packets Powerful but tricky because it requires an in-depth knowledge of other modules (topology, devices, ....) Learning switch, the second module use to forward packet is easier than routing Beginners start from here experimenting the protocol (so rule, actions....) It is also useful to create and debug new modules without having a complex forwarding logic
Fact 2: Fail-over mechanisms require physical loops without the usage of loop-free-technologies -> broadcast storm (ARP, broadcast or multicast protocol....) Common switches use the spanning tree protocol to prevent these kind of situation OF specific says that OF switches show support STP and export the STP_bit to the controller, but most of the virtual switches don’t moreover ususaly controllers can’t intercept and manage these kind of messages coming from the switches PROBLEM: ...leggi slide
We neeed a Plug&Play solution, easy to integrate for beginners as well that makes possible the usage of learning switch with looped topologies, as well if the switches don’t support STP So WE thought to build the MST of the network then deactivating ports outside the minimum spanning tree just computed With these algorithm the goal would be preventing broadcast storm adopting lopped topologies, offering failover mechanisms and saving energy turning electrically off the ports of the switches
- Let’s see how the GreenMST works This is the flow diagram that represents the algorithm CLICK -> each time the controller listen for a new topology change between switches, it generates a linkUpdate event link update event messege contains informations reguarding the change (link added, link removed, .... Which link..) CLICK -> As soon as the linkupdate event arrives, the Minimum Spanning Tree of the updated topology is calculated using the Kruskal algorithm When the computation ends CLICK ports outside the calculated MST are turned off at the same time ports that before were closed, now useful for the new MST are re-opened Once acted on ports their current status (CLICK) is saved for optimization reasons and (CLICK) the system return to the initial state, listening for new linkupdate event
This is a modular view of the solution proposed CLICK -> The already existent topology module keeps the status of the topology updated receiving LLDP notifications Each time a change occurs a new LinkUpdate event is promulgated to the other modules listening for it CLICK -> The GreentMST module intercept the linkUpdate messeges Computes the MST on the new topology informations and turn off/on the ports using the modport command CLICK -> Upper, Learning switch continues to work normaly receiving the PacketIn events from the switches and sending out PacketOuts and flowMods
Spiega come funziona tutto As I was telling you before we build an additional structure has been added to save the last status of the port Port status is saved after each MST computation to do not send a message when it is unusefull