This document discusses using support vector machines (SVM) for nonlinear equalization. It introduces SVM techniques, describing how SVMs find optimal separating hyperplanes to perform classification. The document presents a system model using an SVM equalizer for a nonlinear channel. Simulation results show decision boundaries and bit error rate performance for the SVM equalizer under different configurations and noise scenarios. It is found that a bank of SVMs, each trained for a different signal-to-noise ratio, better handles unknown channel and SNR conditions compared to a single SVM.
Event classification & prediction using support vector machineRuta Kambli
This document provides an overview of event classification and prediction using support vector machines (SVM). It begins with an introduction to classification, machine learning, and SVM. It then discusses binary classification with SVM, including hard-margin and soft-margin SVM, kernels, and multiclass classification. The document presents case studies on classifying hand movements from electromyography data and predicting power grid blackouts using SVM. It concludes that SVM is effective for these classification tasks and can initiate prevention mechanisms for predicted events.
- The document discusses support vector machines (SVMs), a machine learning classification method that finds the decision boundary with the maximum margin between classes.
- It provides an example of a linearly separable classification problem and explains how SVMs aim to find the boundary that maximizes the margin, or minimum distance, between the boundary and the closest data points of each class. These closest points are called the support vectors.
- Formulating SVMs as a quadratic programming problem allows the maximum margin boundary to be found by minimizing a weighted sum of distances subject to constraints ensuring the correct classification of training examples.
Anomaly detection using deep one class classifier홍배 김
The document discusses anomaly detection techniques using deep one-class classifiers and generative adversarial networks (GANs). It proposes using an autoencoder to extract features from normal images, training a GAN on those features to model the distribution, and using a one-class support vector machine (SVM) to determine if new images are within the normal distribution. The method detects and localizes anomalies by generating a binary mask for abnormal regions. It also discusses Gaussian mixture models and the expectation-maximization algorithm for modeling multiple distributions in data.
We consider the problem of finding anomalies in high-dimensional data using popular PCA based anomaly scores. The naive algorithms for computing these scores explicitly compute the PCA of the covariance matrix which uses space quadratic in the dimensionality of the data. We give the first streaming algorithms
that use space that is linear or sublinear in the dimension. We prove general results showing that any sketch of a matrix that satisfies a certain operator norm guarantee can be used to approximate these scores. We instantiate these results with powerful matrix sketching techniques such as Frequent Directions and random projections to derive efficient and practical algorithms for these problems, which we validate over real-world data sets. Our main technical contribution is to prove matrix perturbation
inequalities for operators arising in the computation of these measures.
-Proceedings: https://arxiv.org/abs/1804.03065
-Origin: https://arxiv.org/abs/1804.03065
This document presents the Improved Cepstra Minimum-Mean-Square-Error (ICMMSE) noise reduction algorithm for robust speech recognition. ICMMSE improves on the previous CMMSE algorithm in several ways: it uses an improved minimum controlled recursive averaging algorithm to estimate speech probability more accurately, refines prior signal-to-noise ratio estimation, applies gain smoothing or optimally-modified log-spectral amplitude processing to modify the gain function, and performs two-stage noise reduction processing. Experiments on the Aurora 2, CHiME-3, and Cortana tasks show ICMMSE consistently outperforms CMMSE and baseline systems, achieving relative word error rate reductions of up to 25%.
This document provides an outline for a course on neural networks and fuzzy systems. The course is divided into two parts, with the first 11 weeks covering neural networks topics like multi-layer feedforward networks, backpropagation, and gradient descent. The document explains that multi-layer networks are needed to solve nonlinear problems by dividing the problem space into smaller linear regions. It also provides notation for multi-layer networks and shows how backpropagation works to calculate weight updates for each layer.
This document discusses channel equalization techniques for digital communication systems. It describes four main threats in digital communication channels: inter-symbol interference, multipath propagation, co-channel interference, and noise. It then explains various linear equalization techniques like LMS and NLMS adaptive filters that can be used to mitigate inter-symbol interference. Finally, it discusses the need for non-linear equalizers and how multilayer perceptron neural networks can be used for non-linear channel equalization.
Event classification & prediction using support vector machineRuta Kambli
This document provides an overview of event classification and prediction using support vector machines (SVM). It begins with an introduction to classification, machine learning, and SVM. It then discusses binary classification with SVM, including hard-margin and soft-margin SVM, kernels, and multiclass classification. The document presents case studies on classifying hand movements from electromyography data and predicting power grid blackouts using SVM. It concludes that SVM is effective for these classification tasks and can initiate prevention mechanisms for predicted events.
- The document discusses support vector machines (SVMs), a machine learning classification method that finds the decision boundary with the maximum margin between classes.
- It provides an example of a linearly separable classification problem and explains how SVMs aim to find the boundary that maximizes the margin, or minimum distance, between the boundary and the closest data points of each class. These closest points are called the support vectors.
- Formulating SVMs as a quadratic programming problem allows the maximum margin boundary to be found by minimizing a weighted sum of distances subject to constraints ensuring the correct classification of training examples.
Anomaly detection using deep one class classifier홍배 김
The document discusses anomaly detection techniques using deep one-class classifiers and generative adversarial networks (GANs). It proposes using an autoencoder to extract features from normal images, training a GAN on those features to model the distribution, and using a one-class support vector machine (SVM) to determine if new images are within the normal distribution. The method detects and localizes anomalies by generating a binary mask for abnormal regions. It also discusses Gaussian mixture models and the expectation-maximization algorithm for modeling multiple distributions in data.
We consider the problem of finding anomalies in high-dimensional data using popular PCA based anomaly scores. The naive algorithms for computing these scores explicitly compute the PCA of the covariance matrix which uses space quadratic in the dimensionality of the data. We give the first streaming algorithms
that use space that is linear or sublinear in the dimension. We prove general results showing that any sketch of a matrix that satisfies a certain operator norm guarantee can be used to approximate these scores. We instantiate these results with powerful matrix sketching techniques such as Frequent Directions and random projections to derive efficient and practical algorithms for these problems, which we validate over real-world data sets. Our main technical contribution is to prove matrix perturbation
inequalities for operators arising in the computation of these measures.
-Proceedings: https://arxiv.org/abs/1804.03065
-Origin: https://arxiv.org/abs/1804.03065
This document presents the Improved Cepstra Minimum-Mean-Square-Error (ICMMSE) noise reduction algorithm for robust speech recognition. ICMMSE improves on the previous CMMSE algorithm in several ways: it uses an improved minimum controlled recursive averaging algorithm to estimate speech probability more accurately, refines prior signal-to-noise ratio estimation, applies gain smoothing or optimally-modified log-spectral amplitude processing to modify the gain function, and performs two-stage noise reduction processing. Experiments on the Aurora 2, CHiME-3, and Cortana tasks show ICMMSE consistently outperforms CMMSE and baseline systems, achieving relative word error rate reductions of up to 25%.
This document provides an outline for a course on neural networks and fuzzy systems. The course is divided into two parts, with the first 11 weeks covering neural networks topics like multi-layer feedforward networks, backpropagation, and gradient descent. The document explains that multi-layer networks are needed to solve nonlinear problems by dividing the problem space into smaller linear regions. It also provides notation for multi-layer networks and shows how backpropagation works to calculate weight updates for each layer.
This document discusses channel equalization techniques for digital communication systems. It describes four main threats in digital communication channels: inter-symbol interference, multipath propagation, co-channel interference, and noise. It then explains various linear equalization techniques like LMS and NLMS adaptive filters that can be used to mitigate inter-symbol interference. Finally, it discusses the need for non-linear equalizers and how multilayer perceptron neural networks can be used for non-linear channel equalization.
1. The document discusses various machine learning classification algorithms including neural networks, support vector machines, logistic regression, and radial basis function networks.
2. It provides examples of using straight lines and complex boundaries to classify data with neural networks. Maximum margin hyperplanes are used for support vector machine classification.
3. Logistic regression is described as useful for binary classification problems by using a sigmoid function and cross entropy loss. Radial basis function networks can perform nonlinear classification with a kernel trick.
The document describes a Wiener filtering algorithm for noise suppression in speech signals. It involves estimating the noise and speech power spectral densities (PSDs) using a noise model and all-pole modeling of speech respectively. An iterative Wiener filter is then constructed using the PSD estimates. The algorithm is improved by adding a voice activity detector to estimate noise PSD only from non-speech frames. Evaluation shows the denoised speech has higher intelligibility and a posteriori SNR compared to noisy speech.
Support vector machines (SVM) are a type of supervised machine learning model that constructs hyperplanes to classify data. Least squares support vector machines (LS-SVM) are a variation of SVM that uses equality constraints instead of inequality constraints, solving a system of linear equations instead of a quadratic programming problem. LS-SVM tends to be more suitable than standard SVM for inseparable data and produces solutions that lack the sparseness of SVM.
1) The document discusses various techniques for single-input single-output (SISO) and multiple-input multiple-output (MIMO) wireless communication systems. It begins with an overview of SISO detection using Bayesian approaches like maximum likelihood detection.
2) It then introduces MIMO techniques like diversity and spatial multiplexing. Diversity techniques like space-time coding use multiple transmission paths to improve reliability, while spatial multiplexing uses multiple antennas to increase throughput.
3) Specific diversity techniques discussed include repetition coding, time/frequency diversity, and Alamouti space-time coding. For spatial multiplexing, the document describes the MIMO channel model and mentions maximum likelihood detection for MIMO receivers.
This document provides an overview of support vector machines (SVMs) for machine learning. It explains that SVMs find the optimal separating hyperplane that maximizes the margin between examples of separate classes. This is achieved by formulating SVM training as a convex optimization problem that can be solved efficiently. The document discusses how SVMs can handle non-linear decision boundaries using the "kernel trick" to implicitly map examples to higher-dimensional feature spaces without explicitly performing the mapping.
Super resolution in deep learning era - Jaejun YooJaeJun Yoo
1) The document discusses super-resolution techniques in deep learning, including inverse problems, image restoration problems, and different deep learning models.
2) Early models like SRCNN used convolutional networks for super-resolution but were shallow, while later models incorporated residual learning (VDSR), recursive learning (DRCN), and became very deep and dense (SRResNet).
3) Key developments included EDSR which provided a strong backbone model and GAN-based approaches like SRGAN which aimed to generate more realistic textures but require new evaluation metrics.
This document provides an overview of support vector machines (SVM). It explains that SVM is a supervised machine learning algorithm used for classification and regression. It works by finding the optimal separating hyperplane that maximizes the margin between different classes of data points. The document discusses key SVM concepts like slack variables, kernels, hyperparameters like C and gamma, and how the kernel trick allows SVMs to fit non-linear decision boundaries.
- Support Vector Machine (SVM) is a supervised machine learning algorithm used for both classification and regression problems, but primarily for classification.
- The goal of SVM is to find the optimal separating hyperplane that maximizes the margin between two classes of data points.
- Support vectors are the data points that are closest to the hyperplane and influence its position. SVM aims to position the hyperplane to best separate the support vectors of different classes.
This document provides an introduction to equalization and summarizes several equalization techniques:
1) Zero forcing equalizers aim to completely eliminate intersymbol interference by inverting the channel response but can amplify noise.
2) The mean square error criterion aims to minimize the error between the received and desired signals when filtered by the equalizer. This can be solved using least squares or adaptive algorithms like LMS.
3) The least mean square algorithm approximates the steepest descent method to iteratively and adaptively update the equalizer filter taps to minimize the mean square error based only on instantaneous measurements. This makes it suitable for time-varying channels.
- The document provides an introduction to linear algebra and MATLAB. It discusses various linear algebra concepts like vectors, matrices, tensors, and operations on them.
- It then covers key MATLAB topics - basic data types, vector and matrix operations, control flow, plotting, and writing efficient code.
- The document emphasizes how linear algebra and MATLAB are closely related and commonly used together in applications like image and signal processing.
The slide covers a few state of the art models of word embedding and deep explanation on algorithms for approximation of softmax function in language models.
classification algorithms in machine learning.pptxjasontseng19
The document discusses support vector machines (SVMs), a type of supervised machine learning algorithm. SVMs are used for both classification and regression tasks. They work by finding a hyperplane that maximizes the margin between classes of data in a training set. The goal is to choose the hyperplane that best separates the classes, enabling generalization to new data. The document outlines the theory behind SVMs and how they find the optimal separating hyperplane. It also discusses parameters like the regularization parameter C and gamma value that can be tuned to improve SVM performance.
This document summarizes several distributed algorithms for array signal processing tasks. It begins by describing centralized beamforming and direction-of-arrival estimation techniques that require collecting all sensor data at a central location. It then introduces a distributed system model where an array is partitioned into subarrays that can perform local processing and consensus. The document outlines finite time average consensus, distributed implementations of the power method for computing the sensor covariance matrix eigenvectors, MUSIC algorithm, Capon beamformer, and conjugate gradients. It provides communication complexity analyses and examples of simulations performed using the distributed algorithms.
This document provides an overview of support vector machines (SVMs), a supervised machine learning algorithm used for both classification and regression problems. It explains that SVMs work by finding the optimal hyperplane that separates classes of data by the maximum margin. For non-linear classification, the data is first mapped to a higher dimensional space using kernel functions like polynomial or Gaussian kernels. The document discusses issues like overfitting and soft margins, and notes applications of SVMs in areas like face detection, text categorization, and bioinformatics.
This document discusses training deep neural network (DNN) models. It explains that DNNs have an input layer, multiple hidden layers, and an output layer connected by weights and biases. Training a DNN involves initializing the weights and biases randomly, passing inputs through the network to get outputs, calculating the loss between actual and predicted outputs, and updating the weights to minimize loss using gradient descent and backpropagation. Gradient descent with backpropagation calculates the gradient of the loss with respect to each weight and bias by applying the chain rule to propagate loss backwards through the network.
1. The document describes techniques for implementing complex enumeration for multi-user MIMO vector precoding, including the Schnorr-Euchner enumeration algorithm, circular set enumeration, and neighbour expansion methods.
2. A "puzzle enumerator" technique is proposed that divides the complex plane into regions and locally enumerates nodes within each region to identify the most favorable nodes, without requiring distance computations.
3. The puzzle enumerator, circular set enumeration, and neighbour expansion techniques were implemented on an FPGA. The puzzle enumerator achieved the lowest latency and area occupation compared to other techniques since it does not require distance computations or sorting.
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
1. The document discusses various machine learning classification algorithms including neural networks, support vector machines, logistic regression, and radial basis function networks.
2. It provides examples of using straight lines and complex boundaries to classify data with neural networks. Maximum margin hyperplanes are used for support vector machine classification.
3. Logistic regression is described as useful for binary classification problems by using a sigmoid function and cross entropy loss. Radial basis function networks can perform nonlinear classification with a kernel trick.
The document describes a Wiener filtering algorithm for noise suppression in speech signals. It involves estimating the noise and speech power spectral densities (PSDs) using a noise model and all-pole modeling of speech respectively. An iterative Wiener filter is then constructed using the PSD estimates. The algorithm is improved by adding a voice activity detector to estimate noise PSD only from non-speech frames. Evaluation shows the denoised speech has higher intelligibility and a posteriori SNR compared to noisy speech.
Support vector machines (SVM) are a type of supervised machine learning model that constructs hyperplanes to classify data. Least squares support vector machines (LS-SVM) are a variation of SVM that uses equality constraints instead of inequality constraints, solving a system of linear equations instead of a quadratic programming problem. LS-SVM tends to be more suitable than standard SVM for inseparable data and produces solutions that lack the sparseness of SVM.
1) The document discusses various techniques for single-input single-output (SISO) and multiple-input multiple-output (MIMO) wireless communication systems. It begins with an overview of SISO detection using Bayesian approaches like maximum likelihood detection.
2) It then introduces MIMO techniques like diversity and spatial multiplexing. Diversity techniques like space-time coding use multiple transmission paths to improve reliability, while spatial multiplexing uses multiple antennas to increase throughput.
3) Specific diversity techniques discussed include repetition coding, time/frequency diversity, and Alamouti space-time coding. For spatial multiplexing, the document describes the MIMO channel model and mentions maximum likelihood detection for MIMO receivers.
This document provides an overview of support vector machines (SVMs) for machine learning. It explains that SVMs find the optimal separating hyperplane that maximizes the margin between examples of separate classes. This is achieved by formulating SVM training as a convex optimization problem that can be solved efficiently. The document discusses how SVMs can handle non-linear decision boundaries using the "kernel trick" to implicitly map examples to higher-dimensional feature spaces without explicitly performing the mapping.
Super resolution in deep learning era - Jaejun YooJaeJun Yoo
1) The document discusses super-resolution techniques in deep learning, including inverse problems, image restoration problems, and different deep learning models.
2) Early models like SRCNN used convolutional networks for super-resolution but were shallow, while later models incorporated residual learning (VDSR), recursive learning (DRCN), and became very deep and dense (SRResNet).
3) Key developments included EDSR which provided a strong backbone model and GAN-based approaches like SRGAN which aimed to generate more realistic textures but require new evaluation metrics.
This document provides an overview of support vector machines (SVM). It explains that SVM is a supervised machine learning algorithm used for classification and regression. It works by finding the optimal separating hyperplane that maximizes the margin between different classes of data points. The document discusses key SVM concepts like slack variables, kernels, hyperparameters like C and gamma, and how the kernel trick allows SVMs to fit non-linear decision boundaries.
- Support Vector Machine (SVM) is a supervised machine learning algorithm used for both classification and regression problems, but primarily for classification.
- The goal of SVM is to find the optimal separating hyperplane that maximizes the margin between two classes of data points.
- Support vectors are the data points that are closest to the hyperplane and influence its position. SVM aims to position the hyperplane to best separate the support vectors of different classes.
This document provides an introduction to equalization and summarizes several equalization techniques:
1) Zero forcing equalizers aim to completely eliminate intersymbol interference by inverting the channel response but can amplify noise.
2) The mean square error criterion aims to minimize the error between the received and desired signals when filtered by the equalizer. This can be solved using least squares or adaptive algorithms like LMS.
3) The least mean square algorithm approximates the steepest descent method to iteratively and adaptively update the equalizer filter taps to minimize the mean square error based only on instantaneous measurements. This makes it suitable for time-varying channels.
- The document provides an introduction to linear algebra and MATLAB. It discusses various linear algebra concepts like vectors, matrices, tensors, and operations on them.
- It then covers key MATLAB topics - basic data types, vector and matrix operations, control flow, plotting, and writing efficient code.
- The document emphasizes how linear algebra and MATLAB are closely related and commonly used together in applications like image and signal processing.
The slide covers a few state of the art models of word embedding and deep explanation on algorithms for approximation of softmax function in language models.
classification algorithms in machine learning.pptxjasontseng19
The document discusses support vector machines (SVMs), a type of supervised machine learning algorithm. SVMs are used for both classification and regression tasks. They work by finding a hyperplane that maximizes the margin between classes of data in a training set. The goal is to choose the hyperplane that best separates the classes, enabling generalization to new data. The document outlines the theory behind SVMs and how they find the optimal separating hyperplane. It also discusses parameters like the regularization parameter C and gamma value that can be tuned to improve SVM performance.
This document summarizes several distributed algorithms for array signal processing tasks. It begins by describing centralized beamforming and direction-of-arrival estimation techniques that require collecting all sensor data at a central location. It then introduces a distributed system model where an array is partitioned into subarrays that can perform local processing and consensus. The document outlines finite time average consensus, distributed implementations of the power method for computing the sensor covariance matrix eigenvectors, MUSIC algorithm, Capon beamformer, and conjugate gradients. It provides communication complexity analyses and examples of simulations performed using the distributed algorithms.
This document provides an overview of support vector machines (SVMs), a supervised machine learning algorithm used for both classification and regression problems. It explains that SVMs work by finding the optimal hyperplane that separates classes of data by the maximum margin. For non-linear classification, the data is first mapped to a higher dimensional space using kernel functions like polynomial or Gaussian kernels. The document discusses issues like overfitting and soft margins, and notes applications of SVMs in areas like face detection, text categorization, and bioinformatics.
This document discusses training deep neural network (DNN) models. It explains that DNNs have an input layer, multiple hidden layers, and an output layer connected by weights and biases. Training a DNN involves initializing the weights and biases randomly, passing inputs through the network to get outputs, calculating the loss between actual and predicted outputs, and updating the weights to minimize loss using gradient descent and backpropagation. Gradient descent with backpropagation calculates the gradient of the loss with respect to each weight and bias by applying the chain rule to propagate loss backwards through the network.
1. The document describes techniques for implementing complex enumeration for multi-user MIMO vector precoding, including the Schnorr-Euchner enumeration algorithm, circular set enumeration, and neighbour expansion methods.
2. A "puzzle enumerator" technique is proposed that divides the complex plane into regions and locally enumerates nodes within each region to identify the most favorable nodes, without requiring distance computations.
3. The puzzle enumerator, circular set enumeration, and neighbour expansion techniques were implemented on an FPGA. The puzzle enumerator achieved the lowest latency and area occupation compared to other techniques since it does not require distance computations or sorting.
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
Null Bangalore | Pentesters Approach to AWS IAMDivyanshu
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
Discover the latest insights on Data Driven Maintenance with our comprehensive webinar presentation. Learn about traditional maintenance challenges, the right approach to utilizing data, and the benefits of adopting a Data Driven Maintenance strategy. Explore real-world examples, industry best practices, and innovative solutions like FMECA and the D3M model. This presentation, led by expert Jules Oudmans, is essential for asset owners looking to optimize their maintenance processes and leverage digital technologies for improved efficiency and performance. Download now to stay ahead in the evolving maintenance landscape.
Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
Fuel Cells: Introduction- importance and classification of fuel cells - description, principle, components, applications of fuel cells: H2-O2 fuel cell, alkaline fuel cell, molten carbonate fuel cell and direct methanol fuel cells.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
2. Contents
I. Detection and Equalization
II. Support Vector Machine (SVM) technique
III. System Model
IV. Simulation Results – Decision Boundaries
V. BER Analysis
VI. Summary
3. Equalization – Non Linear
Equalization
Equalization
• Remove ISI and noise effects of the channel
• Located at the receiver
Severe channel effects, linear equalization
methods suffer – Noise enhancement
• Premise for Non-linear equalization
Non-linear equalization challenges
• Architectures maybe unmanageably complex
• Loss of information – nonlinear system maybe non-
invertible
• Computationally intensive
Why not think of it as a classification problem?
4. Why SVM
Train with small amounts of data
Training is straightforward
• Less ad hoc input from designer
Detection stage is efficient
Results Comparable to Volterra filters and
neural Networks
• Volterra filters – dimension grows quickly
• Neural networks – parameters of networks
determined in an ad-hoc fashion
5. Intro to SVM
Separate clouds of data using an optimal
hyperplane
Maximum margin classifiers don’t work well
with outliers
Outlier
Margin
Low Bias
High Variance
6. Intro to SVM
Soft Margins and Outliers
Separate clouds of data using an optimal
hyperplane
Maximum margin classifiers don’t work well
with outliers – Support vector classifiers do
Higher Bias
Low Variance
Allow for misclassifications
Soft Margin
7. Intro to SVM
Linear Classifier Limited
Separate clouds of data using an optimal hyperplane
In 2-Dimensions, the support vector classifier is a line
Support vector machines – Deal with data with high amounts of
overlaps
No matter where you place
the margin, you will obtain a
lot of errors
2 categories, but no obvious
linear classifier to separate
them.
8. Intro to SVM
Non Linear Classifier
Separate clouds of data using an optimal hyperplane
In 2-Dimensions, the support vector classifier is a line
Support vector machines – Deal with data with high amounts of
overlaps – non linear mapping from the pattern space to higher
dimensional feature space to create linearly separable clouds of
data
Move data to
higher dimension
Kernel Functions – Find
support vector classifiers in
higher dimensions
9. Support Vector Machines
Hyperplanes and decision criteria
Objective – Find the weights (w) and bias (b) to define a hyperplane:
𝐰𝑇𝐱 + 𝑏 = 0
Optimal Hyperplane – A
hyperplane for which the
margin of separation is
maximized
Margin of separation is
maximum when norm of
the weight is minimized.
𝑑+
𝑑−
10. Support Vector Machines
Lagrangian Optimization Problem
Primal Problem
min 𝐿𝑝 =
1
2
𝐰 2 −
𝑖=1
𝑙
𝑎𝑖𝑦𝑖 𝐱𝑖 ∙ 𝐰 + 𝑏 +
𝑖=1
𝑙
𝑎𝑖
Dual Optimization problem
max 𝐿𝑑(𝑎𝑖) = 𝑎𝑖 −
1
2
𝑎𝑖𝑎𝑗𝑦𝑖𝑦𝑗𝐾(𝑥𝑖, 𝑥𝑗)
Under Constraints
𝑖=1
𝑙
𝑎𝑖𝑦𝑖 = 0 and 0 ≤ 𝑎𝑖 ≤ 𝐶
Why the dual?
Let’s us solve the problem by computing just the inner
products
𝐾(∙,∙) : Kernel
Polynomial
𝐾 𝑥, 𝑦 = 𝑥 ∙ 𝑦 + 1 𝑝
Radial Basis Function
𝐾 𝑥, 𝑦 = exp
− 𝑥 − 𝑦 2
2𝜎2
Sigmoid Function
𝐾 𝑥, 𝑦 = tanh 𝜅𝑥 ⋅ 𝑦 − 𝛿
11. SVM Classification
Equalization
𝑦 = 𝑠𝑖𝑔𝑛 𝑓 𝐱
𝑦 : Estimate to the classification
𝑓 𝐱 = i∈S αi yiΦ xi ∙ Φ x + b = i∈S αi yi𝐾 xi, x + b
• {𝛼i} – Lagrange Multipliers
• 𝑆 – Set of indices for which 𝑥𝑖 is a support vector
• 𝐾 ∙,∙ - Kernel satisfying conditions of Mercer’s theorem
• 𝑏 – Affine offset
Training set consists of
𝐱𝐢 ∈ 𝐑𝐌
𝐲i ∈ {−1,1}, i = 1, … , L
12. System Model
NN {∙} SVMM
𝑧−𝐷
𝑢 𝑛 ∈ {±1}
𝒚𝒏
𝑓(𝐱)
𝑥(𝑛)
NN {∙} – Nonlinear system
𝑥(𝑛) – Nonlinear system output
𝑢(𝑛) – Training sequence
𝑦𝑛 – Desired output (delayed version of training sequence)
19. Decision Boundaries and SNR
Polynomial Kernel
K 𝐱, 𝐳 = 𝐱T
𝐳 + 1
d
d = polynomial order
All polynomials up to degree d
For our simulation, d = 3
𝐱T
𝐳 + 1
d
= O n computation
Feature space might be non −
unique
20. Decision Boundaries and SNR
RBF Kernel
K 𝐱, 𝐳 = exp −γ 𝐱 − 𝐳 2
2
Infinite dimensional space
Parameter = γ
As γ increases, the model
overfits
As 𝛾 decreases, the model
underfits
For our simulation, 𝛾 = 1
21. Decision Boundaries and SNR
Sigmoid Kernel
K 𝐱, 𝐳 = tanh k𝐱T
𝐳 − δ
k = slope
δ = intercept
For our simulation,
• k = 10, δ = 10
Sigmoidal kernels can be
thought of multi-layer
perceptron
24. Offline Training
Generalization over different SNRs
Training SNRs = 1: 20 dB
Testing SNRs = 1: 20 dB
Does not generalize well
over different SNR values
and multiple channels
25. SVM-Bank for Different SNR signals
SVM (SNR1)
SVM (SNR2)
SVM (SNR𝑁)
Noise
Variance
Estimator
NN {∙}
𝑢 𝑛 ∈ {±1} 𝑥(𝑛)
𝑢(𝑛)
27. Summary
We looked at SVM as a Dual Lagrangian Optimization Problem
and how it fits in non-linear equalization problem.
We developed a non-linear channel communication system and
applied SVM equalizer.
For different values of Detector Delay (D) and SVM kernels, we
found different BER performance of the SVM equalizer.
For Unknown SNR, the SVM equalizer does not generalize well
to unknown channel and unknown SNR.
To solve the issue of SNR, we proposed a bank of SVM with SVM
models trained with different SNR values. After receiving the
signal, noise variance estimator block will select the desired
SVM model for equalization.
We look at the received signals. In the most simplest form, using a two tap channel filter, the symbols will appear in two dimensional space. And using ground values that we know, which are the transmitted symbols, we come up with a decision boundary, so that we can predict future symbols based on that boundary.
Voltera filters – a multiplicative structure creates cross-products of all filter states. These cross-products are then weighted linearly and the proble is to find the optimum weighting that minimizes some cost. The dimension of the model grows quickly, and it becomes necessary to apply some sort of heuristic to limit that model.
Neural networks – iterative, gradient-descent like algorithm that is not guaranteed to find a global optimum but may tend to a local optimum. Neural networks are susceptible to overtraining and that the number of layers, the number of neurons per layer, and when to stop adapting must be determined in an ad hoc fashion.
Support vectors – data points near the optimal hyperplane
Soft margin – the margin when we allow for misclassifications
How do we choose the soft margin? Why should a margin be between those particular blue and green circles? For that we look at the relationship between all data points. We use cross validation to determine how many misclassifications and observations to allow inside of the soft margin to get the best classification. If for validation data, the performance is best when working with the green and blue data points as shown in the lower figure, then we would allow one misclassification. Using a soft margin classifier means using a support vector classifier.
The data points (observations) on the edge and within the soft margin are called support vectors.
Soft margin – the margin when we allow for misclassifications
How do we choose the soft margin? Why should a margin be between those particular blue and green circles? For that we look at the relationship between all data points. We use cross validation to determine how many misclassifications and observations to allow inside of the soft margin to get the best classification. If for validation data, the performance is best when working with the green and blue data points as shown in the lower figure, then we would allow one misclassification. Using a soft margin classifier means using a support vector classifier.
The data points (observations) on the edge and within the soft margin are called support vectors.
There are different types of kernels that can be used. This paper uses a polynomial kernel. A polynomial kernel systematically increases dimensions by setting d, the degree of the polynomial and the relationship between each pair of points is used to find a support vector classifier in that dimension. A good value of the degree is obtained by cross validation.
By differentiating the primal problem and equating to zeros, we get solutions for weight vector w and the bias b, which when we substitute to the original problem gives us the dual form below, where there is no dependence on w and b anymore.
What is a kernel and what are the different options for it
M – Equalizer dimension, D – Lag, d – Polynomial Kernel Order
The Decision boundary similar to the optimum and is logical in terms of the training data. The optimum for this example includes a disconnected region, but the SVM cannot match the polygon nature of the optimum.