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Energy-Economical Heuristically Based Control Of Compass Gait Walking On Stochastically Varying Terrain, Christian Hubicki Jan 2011

Energy-Economical Heuristically Based Control Of Compass Gait Walking On Stochastically Varying Terrain, Christian Hubicki

Master’s Theses

Investigation uses simulation to explore the inherent tradeoffs ofcontrolling high-speed and highly robust walking robots while minimizing energy consumption. Using a novel controller which optimizes robustness, energy economy, and speed of a simulated robot on rough terrain, the user can adjust their priorities between these three outcome measures and systematically generate a performance curveassessing the tradeoffs associated with these metrics.


Combining Natural Language Processing And Statistical Text Mining: A Study Of Specialized Versus Common Languages, Jay Jarman Jan 2011

Combining Natural Language Processing And Statistical Text Mining: A Study Of Specialized Versus Common Languages, Jay Jarman

USF Tampa Graduate Theses and Dissertations

This dissertation focuses on developing and evaluating hybrid approaches for analyzing free-form text in the medical domain. This research draws on natural language processing (NLP) techniques that are used to parse and extract concepts based on a controlled vocabulary. Once important concepts are extracted, additional machine learning algorithms, such as association rule mining and decision tree induction, are used to discover classification rules for specific targets. This multi-stage pipeline approach is contrasted with traditional statistical text mining (STM) methods based on term counts and term-by-document frequencies. The aim is to create effective text analytic processes by adapting and combining individual …


Assessing Data Quality In A Sensor Network For Environmental Monitoring, Gesuri Ramirez Jan 2011

Assessing Data Quality In A Sensor Network For Environmental Monitoring, Gesuri Ramirez

Open Access Theses & Dissertations

Assessing the quality of sensor data in environmental monitoring applications is important, as erroneous readings produced by malfunctioning sensors, calibration drift, and problematic climatic conditions, such as icing or dust, are common.Traditional data quality checking and correction is a painstaking manual process, so the development of automatic systems for this task is highly desirable.

This study investigates machine learning methods to identify and clean incorrect data from a real-world environmental sensor network, the Jornada Experimental Range, located in Southern New Mexico. We evaluated several learning algorithms and data replacement schemes, and developed a method to identify the problematic sensor. The …


Algorithms For Training Large-Scale Linear Programming Support Vector Regression And Classification, Pablo Rivas Perea Jan 2011

Algorithms For Training Large-Scale Linear Programming Support Vector Regression And Classification, Pablo Rivas Perea

Open Access Theses & Dissertations

The main contribution of this dissertation is the development of a method to train a Support Vector Regression (SVR) model for the large-scale case where the number of training samples supersedes the computational resources. The proposed scheme consists of posing the SVR problem entirely as a Linear Programming (LP) problem and on the development of a sequential optimization method based on variables decomposition, constraints decomposition, and the use of primal-dual interior point methods. Experimental results demonstrate that the proposed approach has comparable performance with other SV-based classifiers. Particularly, experiments demonstrate that as the problem size increases, the sparser the solution …


Automated Semantic Understanding Of Human Emotions In Writing And Speech, Ricardo A. Calix Jan 2011

Automated Semantic Understanding Of Human Emotions In Writing And Speech, Ricardo A. Calix

LSU Doctoral Dissertations

Affective Human Computer Interaction (A-HCI) will be critical for the success of new technologies that will prevalent in the 21st century. If cell phones and the internet are any indication, there will be continued rapid development of automated assistive systems that help humans to live better, more productive lives. These will not be just passive systems such as cell phones, but active assistive systems like robot aides in use in hospitals, homes, entertainment room, office, and other work environments. Such systems will need to be able to properly deduce human emotional state before they determine how to best interact with …


Prestructuring Multilayer Perceptrons Based On Information-Theoretic Modeling Of A Partido-Alto-Based Grammar For Afro-Brazilian Music: Enhanced Generalization And Principles Of Parsimony, Including An Investigation Of Statistical Paradigms, Mehmet Vurkaç Jan 2011

Prestructuring Multilayer Perceptrons Based On Information-Theoretic Modeling Of A Partido-Alto-Based Grammar For Afro-Brazilian Music: Enhanced Generalization And Principles Of Parsimony, Including An Investigation Of Statistical Paradigms, Mehmet Vurkaç

Dissertations and Theses

The present study shows that prestructuring based on domain knowledge leads to statistically significant generalization-performance improvement in artificial neural networks (NNs) of the multilayer perceptron (MLP) type, specifically in the case of a noisy real-world problem with numerous interacting variables.

The prestructuring of MLPs based on knowledge of the structure of a problem domain has previously been shown to improve generalization performance. However, the problem domains for those demonstrations suffered from significant shortcomings: 1) They were purely logical problems, and 2) they contained small numbers of variables in comparison to most data-mining applications today. Two implications of the former were …


Optimal Control For Autonomous Motor Behavior, Tom Erez Jan 2011

Optimal Control For Autonomous Motor Behavior, Tom Erez

All Theses and Dissertations (ETDs)

This dissertation presents algorithms that allow robots to generate optimal behavior from first principles. Instead of hard-coding every desired behavior, we encode the task as a cost function, and use numerical optimization to find action sequences that can accomplish the task. Using the theoretical framework of optimal control, we develop methods for generating autonomous motor behavior in high-dimensional domains of legged locomotion. We identify three foundational problems that limit the application of existing optimal control algorithms, and present guiding principles that address these issues. First, some traditional algorithms use global optimization, where every possible state is considered. This approach cannot …


Prediction Of Brain Tumor Progression Using Multiple Histogram Matched Mri Scans, Debrup Banerjee, Loc Tran, Jiang Li, Yuzhong Shen, Frederic Mckenzie, Jihong Wang, Ronald M. Summers (Ed.), Bram Van Ginneken (Ed.) Jan 2011

Prediction Of Brain Tumor Progression Using Multiple Histogram Matched Mri Scans, Debrup Banerjee, Loc Tran, Jiang Li, Yuzhong Shen, Frederic Mckenzie, Jihong Wang, Ronald M. Summers (Ed.), Bram Van Ginneken (Ed.)

Electrical & Computer Engineering Faculty Publications

In a recent study [1], we investigated the feasibility of predicting brain tumor progression based on multiple MRI series and we tested our methods on seven patients' MRI images scanned at three consecutive visits A, B and C. Experimental results showed that it is feasible to predict tumor progression from visit A to visit C using a model trained by the information from visit A to visit B. However, the trained model failed when we tried to predict tumor progression from visit B to visit C, though it is clinically more important. Upon a closer look at the MRI scans …


Features Extraction Using Random Matrix Theory., Viktoria Borisovna Rojkova Dec 2010

Features Extraction Using Random Matrix Theory., Viktoria Borisovna Rojkova

Electronic Theses and Dissertations

Representing the complex data in a concise and accurate way is a special stage in data mining methodology. Redundant and noisy data affects generalization power of any classification algorithm, undermines the results of any clustering algorithm and finally encumbers the monitoring of large dynamic systems. This work provides several efficient approaches to all aforementioned sides of the analysis. We established, that notable difference can be made, if the results from the theory of ensembles of random matrices are employed. Particularly important result of our study is a discovered family of methods based on projecting the data set on different subsets …


Three Algorithms For Causal Learning, Roshan Ram Rammohan Dec 2010

Three Algorithms For Causal Learning, Roshan Ram Rammohan

Computer Science ETDs

The field of causal learning has grown in the past decade, establishing itself as a major focus in artificial intelligence research. Traditionally, approaches to causal learning are split into two areas. One area involves the learning of structures from observational data alone and the second, involves the methodologies of conducting and learning from experiments. In this dissertation, I investigate three different aspects of causal learning, all of which are based on the causal Bayesian network framework. Constraint based structure search algorithms that learn partially directed acyclic graphs as causal models from observational data rely on the faithfulness assumption, which is …


Identification And Optimization Of Classifier Genes From Multi-Class Earthworm Microarray Dataset, Ying Li, Nan Wang, Chaoyang Zhang, Ping Gong Oct 2010

Identification And Optimization Of Classifier Genes From Multi-Class Earthworm Microarray Dataset, Ying Li, Nan Wang, Chaoyang Zhang, Ping Gong

Faculty Publications

Monitoring, assessment and prediction of environmental risks that chemicals pose demand rapid and accurate diagnostic assays. A variety of toxicological effects have been associated with explosive compounds TNT and RDX. One important goal of microarray experiments is to discover novel biomarkers for toxicity evaluation. We have developed an earthworm microarray containing 15,208 unique oligo probes and have used it to profile gene expression in 248 earthworms exposed to TNT, RDX or neither. We assembled a new machine learning pipeline consisting of several well-established feature filtering/selection and classification techniques to analyze the 248-array dataset in order to construct classifier models that …


Event-Driven Similarity And Classification Of Scanpaths, Thomas Grindinger Aug 2010

Event-Driven Similarity And Classification Of Scanpaths, Thomas Grindinger

All Dissertations

Eye tracking experiments often involve recording the pattern of deployment of visual attention over the stimulus as viewers perform a given task (e.g., visual search). It is useful in training applications, for example, to make available an expert's sequence of eye movements, or scanpath, to novices for their inspection and subsequent learning. It may also be potentially useful to be able to assess the conformance of the novice's scanpath to that of the expert. A computational tool is proposed that provides a framework for performing such classification, based on the use of a probabilistic machine learning algorithm. The approach was …


Malware Type Recognition And Cyber Situational Awareness, Thomas E. Dube, Richard A. Raines, Gilbert L. Peterson, Kenneth W. Bauer, Michael R. Grimaila, Steven K. Rogers Aug 2010

Malware Type Recognition And Cyber Situational Awareness, Thomas E. Dube, Richard A. Raines, Gilbert L. Peterson, Kenneth W. Bauer, Michael R. Grimaila, Steven K. Rogers

Faculty Publications

Current technologies for computer network and host defense do not provide suitable information to support strategic and tactical decision making processes. Although pattern-based malware detection is an active research area, the additional context of the type of malware can improve cyber situational awareness. This additional context is an indicator of threat capability thus allowing organizations to assess information losses and focus response actions appropriately. Malware Type Recognition (MaTR) is a research initiative extending detection technologies to provide the additional context of malware types using only static heuristics. Test results with MaTR demonstrate over a 99% accurate detection rate and 59% …


Vowel Recognition From Continuous Articulatory Movements For Speaker-Dependent Applications, Jun Wang, Jordan R. Green, Ashok Samal, Tom D. Carrell Aug 2010

Vowel Recognition From Continuous Articulatory Movements For Speaker-Dependent Applications, Jun Wang, Jordan R. Green, Ashok Samal, Tom D. Carrell

Department of Special Education and Communication Disorders: Faculty Publications

A novel approach was developed to recognize vowels from continuous tongue and lip movements. Vowels were classified based on movement patterns (rather than on derived articulatory features, e.g., lip opening) using a machine learning approach. Recognition accuracy on a single-speaker dataset was 94.02% with a very short latency. Recognition accuracy was better for high vowels than for low vowels. This finding parallels previous empirical findings on tongue movements during vowels. The recognition algorithm was then used to drive an articulation-to-acoustics synthesizer. The synthesizer recognizes vowels from continuous input stream of tongue and lip movements and plays the corresponding sound samples …


Analysis Of The Economic Sustainability Of Companies In The Water Sector, Lyubomir Halachev, A. Guergachi, Yashodhan Athavale, Sri Krishnan Jul 2010

Analysis Of The Economic Sustainability Of Companies In The Water Sector, Lyubomir Halachev, A. Guergachi, Yashodhan Athavale, Sri Krishnan

International Congress on Environmental Modelling and Software

Many recent studies look at the issue of sustainability from the environmental and the social points of view. This paper takes a different approach and proposes to look at the economic stability of organizations in the water sector. It analyzes a set of 140 companies from around the world involved in this sector, and attempts to develop a methodology to find out, based on stock market data only, which ones will likely remain active in the foreseeable future, and which ones will likely "die" out. This methodology uses machine learning techniques to handle the stock price time series of companies …


Analysis Of The Economic Sustainability Of Companies In The Water Sector, Lyubomir Halachev, A. Guergachi, Yashodhan Athavale, Sri Krishnan Jul 2010

Analysis Of The Economic Sustainability Of Companies In The Water Sector, Lyubomir Halachev, A. Guergachi, Yashodhan Athavale, Sri Krishnan

International Congress on Environmental Modelling and Software

Many recent studies look at the issue of sustainability from the environmental and the social points of view. This paper takes a different approach and proposes to look at the economic stability of organizations in the water sector. It analyzes a set of 140 companies from around the world involved in this sector, and attempts to develop a methodology to find out, based on stock market data only, which ones will likely remain active in the foreseeable future, and which ones will likely "die" out. This methodology uses machine learning techniques to handle the stock price time series of companies …


Autocalibration Of Integrated Lake Water Quality Models For The Lake Winnipeg Basin Initiative, Markiyan Sloboda, David Swayne, William Booty, Craig Mccrimmon, Isaac Wong Jul 2010

Autocalibration Of Integrated Lake Water Quality Models For The Lake Winnipeg Basin Initiative, Markiyan Sloboda, David Swayne, William Booty, Craig Mccrimmon, Isaac Wong

International Congress on Environmental Modelling and Software

Machine learning (ML) and genetic algorithm (GA) are well known techniques which can be used to calibrate environmental models. This paper investigates the calibration of the 2-D horizontal, vertically mixed lake models OneLay and PolTra using ML and GA routines. A GA was used jointly with the Open Modelling Interface (OpenMI) wrapper approach on a single powerful server. Explicit and implicit gridded approaches with the Probably Approximately Correct (PAC) learning were used as ML techniques. Monte Carlo simulations were used to generate the model input parameters for explicit and implicit gridding. Parallel computing using Shared Hierarchical Academic Computing Network (SHARCNET) …


Integration Of Statistical And Machine Learning Models For Short-Term Forecasting Of The Atmospheric Clearness Index, L. Mora-López, M. Piliougine, J. E. Carretero, M. Sidrach-De-Cardona Jul 2010

Integration Of Statistical And Machine Learning Models For Short-Term Forecasting Of The Atmospheric Clearness Index, L. Mora-López, M. Piliougine, J. E. Carretero, M. Sidrach-De-Cardona

International Congress on Environmental Modelling and Software

We have developed a framework that integrates statistical and machine learning models for the short-term forecasting of a climatic parameter know as the atmospheric clearness index. We have used a multivariate regression to establish the most significant variable amongst all the previous values for the clearness index series. The value of this variable was used to divide all the available data in several intervals. Three different models were used to select the model that best fits the observations for each of these intervals. With this set of models, one for each interval, we have built a framework that enables the …


Autocalibration Of Integrated Lake Water Quality Models For The Lake Winnipeg Basin Initiative, Markiyan Sloboda, David Swayne, William Booty, Craig Mccrimmon, Isaac Wong Jul 2010

Autocalibration Of Integrated Lake Water Quality Models For The Lake Winnipeg Basin Initiative, Markiyan Sloboda, David Swayne, William Booty, Craig Mccrimmon, Isaac Wong

International Congress on Environmental Modelling and Software

Machine learning (ML) and genetic algorithm (GA) are well known techniques which can be used to calibrate environmental models. This paper investigates the calibration of the 2-D horizontal, vertically mixed lake models OneLay and PolTra using ML and GA routines. A GA was used jointly with the Open Modelling Interface (OpenMI) wrapper approach on a single powerful server. Explicit and implicit gridded approaches with the Probably Approximately Correct (PAC) learning were used as ML techniques. Monte Carlo simulations were used to generate the model input parameters for explicit and implicit gridding. Parallel computing using Shared Hierarchical Academic Computing Network (SHARCNET) …


Integration Of Statistical And Machine Learning Models For Short-Term Forecasting Of The Atmospheric Clearness Index, L. Mora-López, M. Piliougine, J. E. Carretero, M. Sidrach-De-Cardona Jul 2010

Integration Of Statistical And Machine Learning Models For Short-Term Forecasting Of The Atmospheric Clearness Index, L. Mora-López, M. Piliougine, J. E. Carretero, M. Sidrach-De-Cardona

International Congress on Environmental Modelling and Software

We have developed a framework that integrates statistical and machine learning models for the short-term forecasting of a climatic parameter know as the atmospheric clearness index. We have used a multivariate regression to establish the most significant variable amongst all the previous values for the clearness index series. The value of this variable was used to divide all the available data in several intervals. Three different models were used to select the model that best fits the observations for each of these intervals. With this set of models, one for each interval, we have built a framework that enables the …


Application Of Pattern Recognition And Adaptive Dsp Methods For Spatio-Temporal Analysis Of Satellite Based Hydrological Datasets, Anish Chand Turlapaty May 2010

Application Of Pattern Recognition And Adaptive Dsp Methods For Spatio-Temporal Analysis Of Satellite Based Hydrological Datasets, Anish Chand Turlapaty

Theses and Dissertations

Data assimilation of satellite-based observations of hydrological variables with full numerical physics models can be used to downscale these observations from coarse to high resolution to improve microwave sensor-based soil moisture observations. Moreover, assimilation can also be used to predict related hydrological variables, e.g., precipitation products can be assimilated in a land information system to estimate soil moisture. High quality spatio-temporal observations of these processes are vital for a successful assimilation which in turn needs a detailed analysis and improvement. In this research, pattern recognition and adaptive signal processing methods are developed for the spatio-temporal analysis and enhancement of soil …


Dealing With Activities With Diffuse Boundaries, Juan Ye, Lorcan Coyle, Susan Mckeever, Simon Dobson May 2010

Dealing With Activities With Diffuse Boundaries, Juan Ye, Lorcan Coyle, Susan Mckeever, Simon Dobson

Conference papers

Activity recognition has mainly focused to date on identifying repetitious and/or clearly delineated events. Our experience, drawing on many years’ research in smart and sensorised systems, leads us to observe that many (if not most) interesting activities fall into a different category: sporadically occurring and poorly differentiated from other concurrent activities. This implies that decision-making remains uncertain across the entire system, and suggests that progress would be greatly supported by standard evaluation methodologies and data sets.


A Comparative Study On Text Categorization, Aditya Chainulu Karamcheti May 2010

A Comparative Study On Text Categorization, Aditya Chainulu Karamcheti

UNLV Theses, Dissertations, Professional Papers, and Capstones

Automated text categorization is a supervised learning task, defined as assigning category labels to new documents based on likelihood suggested by a training set of labeled documents. Two examples of methodology for text categorizations are Naive Bayes and K-Nearest Neighbor.

In this thesis, we implement two categorization engines based on Naive Bayes and K-Nearest Neighbor methodology. We then compare the effectiveness of these two engines by calculating standard precision and recall for a collection of documents. We will further report on time efficiency of these two engines.


Segmentation And Fracture Detection In X-Ray Images For Traumatic Pelvic Injury, Rebecca Smith Apr 2010

Segmentation And Fracture Detection In X-Ray Images For Traumatic Pelvic Injury, Rebecca Smith

Theses and Dissertations

Due to the risk of complications such as hemorrhage, severe pelvic trauma is associated with a high mortality rate. Prompt medical treatment is therefore vital. However, the complexity of the injuries can make successful diagnosis and treatment challenging. By generating predictions and recommendations based on patient data, computer-aided decision support systems have the potential to assist physicians in improving outcomes. However, no current system considers features automatically extracted from medical images. This dissertation describes a system to extract diagnostic features from pelvic X-ray images that can be used as input to the prediction process; specifically, the presence of fracture and …


Semi-Supervised Self-Learning On Imbalanced Data Sets, John Nicholas Korecki Apr 2010

Semi-Supervised Self-Learning On Imbalanced Data Sets, John Nicholas Korecki

USF Tampa Graduate Theses and Dissertations

Semi-supervised self-learning algorithms have been shown to improve classifier accuracy under a variety of conditions. In this thesis, semi-supervised self-learning using ensembles of random forests and fuzzy c-means clustering similarity was applied to three data sets to show where improvement is possible over random forests alone. Two of the data sets are emulations of large simulations in which the data may be distributed. Additionally, the ratio of majority to minority class examples in the training set was altered to examine the effect of training set bias on performance when applying the semi-supervised algorithm.


Developing Cyberspace Data Understanding Using Crisp-Dm For Host-Based Ids Feature Mining, Joseph R. Erskine, Gilbert L. Peterson, Barry E. Mullins, Michael R. Grimaila Apr 2010

Developing Cyberspace Data Understanding Using Crisp-Dm For Host-Based Ids Feature Mining, Joseph R. Erskine, Gilbert L. Peterson, Barry E. Mullins, Michael R. Grimaila

Faculty Publications

Current intrusion detection systems (IDS) generate a large number of specific alerts, but typically do not provide actionable information. Compounding this problem is the fact that many alerts are false positive alerts. This paper applies the Cross Industry Standard Process for Data Mining (CRISP-DM) to develop an understanding of a host environment under attack. Data is generated by launching scans and exploits at a machine outfitted with a set of host-based forensic data collectors. Through knowledge discovery, features are selected to project human understanding of the attack process into the IDS model. By discovering relationships between the data collected and …


Inference Of Cancer-Specific Gene Regulatory Networks Using Soft Computing Rules., Xiaosheng Wang, Osamu Gotoh Mar 2010

Inference Of Cancer-Specific Gene Regulatory Networks Using Soft Computing Rules., Xiaosheng Wang, Osamu Gotoh

Journal Articles: Genetics, Cell Biology & Anatomy

Perturbations of gene regulatory networks are essentially responsible for oncogenesis. Therefore, inferring the gene regulatory networks is a key step to overcoming cancer. In this work, we propose a method for inferring directed gene regulatory networks based on soft computing rules, which can identify important cause-effect regulatory relations of gene expression. First, we identify important genes associated with a specific cancer (colon cancer) using a supervised learning approach. Next, we reconstruct the gene regulatory networks by inferring the regulatory relations among the identified genes, and their regulated relations by other genes within the genome. We obtain two meaningful findings. One …


A Study Of Recent Classification Algorithms And A Novel Approach For Biosignal Data Classification, Eyup Cinar Jan 2010

A Study Of Recent Classification Algorithms And A Novel Approach For Biosignal Data Classification, Eyup Cinar

Theses

Analyzing and understanding human biosignals have been important research areas that have many practical applications in everyday life. For example, Brain Computer Interface is a research area that studies the connection between the human brain and external systems by processing and learning the brain signals called Electroencephalography (EEG) signals. Similarly, various assistive robotics applications are being developed to interpret eye or muscle signals in humans in order to provide control inputs for external devices. The efficiency for all of these applications depends heavily on being able to process and classify human biosignals. Therefore many techniques from Signal Processing and Machine …


Prediction Of Brain Tumor Progression Using A Machine Learning Technique, Yuzhong Shen, Debrup Banerjee, Jiang Li, Adam Chandler, Yufei Shen, Frederic D. Mckenzie, Jihong Wang, Nico Karssemeijer (Ed.), Ronald M. Summers (Ed.) Jan 2010

Prediction Of Brain Tumor Progression Using A Machine Learning Technique, Yuzhong Shen, Debrup Banerjee, Jiang Li, Adam Chandler, Yufei Shen, Frederic D. Mckenzie, Jihong Wang, Nico Karssemeijer (Ed.), Ronald M. Summers (Ed.)

Electrical & Computer Engineering Faculty Publications

A machine learning technique is presented for assessing brain tumor progression by exploring six patients' complete MRI records scanned during their visits in the past two years. There are ten MRI series, including diffusion tensor image (DTI), for each visit. After registering all series to the corresponding DTI scan at the first visit, annotated normal and tumor regions were overlaid. Intensity value of each pixel inside the annotated regions were then extracted across all of the ten MRI series to compose a 10 dimensional vector. Each feature vector falls into one of three categories:normal, tumor, and normal but progressed to …


A Boosting Framework For Visuality-Preserving Distance Metric Learning And Its Application To Medical Image Retrieval, Yang Liu, Rong Jin, Lily Mummert, Rahul Sukthankar, Adam Goode, Bin Zheng, Steven C. H. Hoi, Mahadev Satyanarayanan Jan 2010

A Boosting Framework For Visuality-Preserving Distance Metric Learning And Its Application To Medical Image Retrieval, Yang Liu, Rong Jin, Lily Mummert, Rahul Sukthankar, Adam Goode, Bin Zheng, Steven C. H. Hoi, Mahadev Satyanarayanan

Research Collection School Of Computing and Information Systems

Similarity measurement is a critical component in content-based image retrieval systems, and learning a good distance metric can significantly improve retrieval performance. However, despite extensive study, there are several major shortcomings with the existing approaches for distance metric learning that can significantly affect their application to medical image retrieval. In particular, "similarity" can mean very different things in image retrieval: resemblance in visual appearance (e.g., two images that look like one another) or similarity in semantic annotation (e.g., two images of tumors that look quite different yet are both malignant). Current approaches for distance metric learning typically address only one …