434 research outputs found
Capturing an Evader in a Polygonal Environment With Obstacles
No full textWe study a pursuit-evasion game in which one or more cops try to capture a robber by moving onto a robber's current location. All players have equal maximum velocities. We show that three cops can capture the robber in any polygonal environment which can contain any finite number of holes.Bhadauria, Deepak; Gosse, Shaun; Pipp, Joseph. (2010). Capturing an Evader in a Polygonal Environment With Obstacles. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/215845
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Relational Care - with Mary Larkin and Manik Deepak-Gopinath [Podcast]
No full textWhat is 'relational care' and how can it improve the day-to-day experience of carers and those they care for? What are its implications for relationships between staff and service users in care settings? And how does the concept of relational care enable us to re-imagine the role of place and space in the experience of care? These are some of the questions we explore in this episode with Mary Larkin and Manik Deepak-Gopinath who recently completed a research project on the value and practice of relational care with older people.
Mary is Professor of Care, Carers and Caring at The Open University in the UK, where her research has focused on carers and caring and adult social care. She is the co-author, most recently of Family Carers and Caring, published in 2023 by Emerald. Manik is a Lecturer in Ageing, also at The Open University, and is a critical gerontologist with interests in the intersection of ageing, place and wellbeing, and in the intimate and family ties of older adults
My Name Is Deepak
No full textThis chapter looks at the author's responses to being given a nickname by his co-workers: Tupac. They do it in a friendly manner, but the author doesn’t understand the connection with the American rapper. It makes him think about who he is, his identity, and how people see him in his adopted country.</p
Efficient Data Collection from Wireless Nodes under Two-Ring Communication Model
No full textWe introduce a new geometric routing problem which arises in data muling applications where a mobile robot is charged with collecting data from stationary sensors. The objective is to compute the robot's trajectory and download sequence so as to minimize the time to collect the data from all sensors. The total data collection time has two components: the robot's travel time and the download time. The time to download data from a sensor is a function of the locations of the robot and : If the robot is a distance away from , it can download the sensor's data in units of time. If the distance is greater than but less than , the download time is T_{out} > T_{in}. Otherwise, the robot can not download the data from . Here, , , and are input parameters. We refer to this model, which is based on recently developed experimental models for sensor network deployments, as the two ring model, and the problem of downloading data from a given set of sensors in minimum amount of time under this model as the Two-Ring Tour (TRT) problem.
We present approximation algorithms for the general case which uses solutions to the Traveling Salesperson with Neighborhoods (TSPN) Problem as subroutines. We also present efficient solutions to special but practically important versions of the problem such as uniform and sparse deploymentsBhadauria, Deepak; Tekdas, Onur. (2011). Efficient Data Collection from Wireless Nodes under Two-Ring Communication Model. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/215862
Sideffective - system to mine patient reviews: sentiment analysis
No full textSideffective is the system to crawl, rank and analyze patient testimonials about side ffeects from common medications. Since the wealth of any mining model is the Data corpus, the data collection phase involved extensive crawling of massive medical websites comprised of user forums from the internet. Subsequently, the raw files were subjected to certain site-specific parsing routines, yielding outputs conforming to a well-defined data model. Currently, the system holds close to 400,000 user testimonials pertaining to more than 2500 drugs/medicines. Sideffective aims at gathering and aggregating this wealth of information, build useful associations and present interesting observations and numeric validations, all in a user-friendly interface. The important issues that we have tried to tackle are: Extracting side effects without relying on pre-built lists, aggregating distribution of different side effect for a give drug, site-specific search, ranking and determining the negativity of reviews. The system has been jointly built by Deepak Yalamanchi and Sangeetha Rajagopalan under the guidance of Prof. Tomasz Imielinski. This thesis focuses mainly on Sentiment Analysis of patient reviews. While most existing sentiment analysis systems are predicated by POS (parts of speech) tagging or Bayesian sentiment analysis methods, the same cannot be applied to medical reviews as they generally carry a negative flavor in them. We thereby approached the problem by identifying the features in the sentence and calibrating the sentiment on a Negativity Meter based on their relation to sentiment words. A feature, as defined for the purpose of this thesis, can be a medicine, a side effect or a symptom. The sentiment of each feature is determined by the aggregate of all its polarities with respect to each sentiment word, where the polarity is determined by an inverse relation to the distance of the feature from the sentiment word. Each sentence is then evaluated by the cumulative polarity of all the features contained in it. Sentiment of a review is determined by individually determining the sentiment of each sentence and then getting a weighted sum score of all the sentences in the review. The accuracy of a sentiment analysis system is, in principle, how well it agrees with human judgments. Experimental results, involving human reviewers (extracted from site: www.askapatient.com) and correlating them back to the negativity rating of each review yield conclusive results, demonstrating the effectiveness of the technique. We have also implemented a customized Lucene search on the data using a multi-review summarization approach and a ranking scheme based on the feature-list. Ranking priority is given to the review that has the largest feature list size.M.S.Includes bibliographical referencesby Deepak Yalamanch
Path planning algorithms for robots in a data muling system
No full textUniversity of Minnesota M.S. thesis. December 2010. Major: Computer Science and Engineering. Advisor: Prof. Volkan Isler. 1 computer file (PDF); viii, 66 pages.We study two path planning problems that arise in data muling systems where robots
are charged to collect data from wireless devices dispersed across a large environment.
In such applications, deploying a network of stationary wireless sensors may be infeasible
when many relay nodes are deployed to ensure connectivity. Instead, a few robots can
be used as data mules to collect data from these devices.
The first problem studied in this thesis is to find tours for multiple robots so as
to collect data from all sensors in the least amount of time. We refer to this problem
as the Data Gathering Problem (DGP). We assume that sensors have a uniform disk
communication model. In this model, data can be downloaded from a sensor with
fixed rate inside its communication disk. We present an optimal algorithm for the one
dimensional version of DGP. For the two dimensional version we present a constant
factor approximation algorithm. Afterwards, we present field experiments in which an
autonomous robotic data mule collects data from sensor nodes deployed over a large
area.
Next, we study data collection problem with a more realistic communication model
for sensors. In experiments we found that the time taken to download data from a
sensor s is a function of the locations of the robot and s: If the robot is a distance
rin away from s, it can download the sensor’s data reliably in Tin units of time. If the
distance is greater than rin but less than rout , robot can still download data but due to
higher packet loss probability the average download time Tout is higher (Tout > Tin). We
refer to this model as the Two-Ring communication model and the corresponding path
planning problem as the Two-Ring Tour (TRT) problem. We present a constant factor
approximation algorithm for the general case. The algorithm uses a polynomial time
approximation scheme as a subroutine. Though the scheme has polynomial running
time, its running time is impractically large. It is also very complex to implement.
Therefore we study special cases of the TRT problem and present efficient algorithms
for them.
For robotic data mules to be useful, the robots must be capable of operating in the
field for extended periods of time. Therefore, in the last part of the thesis we initiate
ii
the study of solar energy harvesting for robotic navigation. Our primary contribution
is an experimental model of energy consumption and harvesting as a function of environmental
parameters. We demonstrate the utility of this model in a simple navigation
task.Bhadauria, Deepak. (2010). Path planning algorithms for robots in a data muling system. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/104135
Building Thermal Performance Varies During Extreme Heat within Cities
No full textabstract: This document has been superseded by our peer-reviewed publication:
Building Thermal Performance, Climate Change, and Urban Heat Vulnerability, Matthew Nahlik, Mikhail Chester, Stephanie Pincetl, David Eisenman, Deepak Sivaraman, and Paul English, 2017, ASCE Journal of Infrastructure Systems, 23(3), doi:10.1061/(ASCE)IS.1943-555X.0000349
The publication is available at: http://dx.doi.org/10.1061/(ASCE)IS.1943-555X.0000349
The leading source of weather-related deaths in the United States is heat, and future projections show that the frequency, duration, and intensity of heat events will increase in the Southwest. Presently, there is a dearth of knowledge about how infrastructure may perform during heat waves or could contribute to social vulnerability. To understand how buildings perform in heat and potentially stress people, indoor air temperature changes when air conditioning is inaccessible are modeled for building archetypes in Los Angeles, California, and Phoenix, Arizona, when air conditioning is inaccessible is estimated. An energy simulation model is used to estimate how quickly indoor air temperature changes when building archetypes are exposed to extreme heat. Building age and geometry (which together determine the building envelope material composition) are found to be the strongest indicators of thermal envelope performance. Older neighborhoods in Los Angeles and Phoenix (often more centrally located in the metropolitan areas) are found to contain the buildings whose interiors warm the fastest, raising particular concern because these regions are also forecast to experience temperature increases. To combat infrastructure vulnerability and provide heat refuge for residents, incentives should be adopted to strategically retrofit buildings where both socially vulnerable populations reside and increasing temperatures are forecast
Building and processing a dataset containing articles related to food adulteration
No full textThesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (page 69).In this thesis, I explored the problem of building a dataset containing news articles related to adulteration, and curating this dataset in an automated fashion. In particular, we looked at food-adulterant co-existence detection, query reforumulation, and entity extraction and text deduplication. All proposed algorithms were implemented in Python, and performance was evaluated on multiple datasets. Methods described in this thesis can be generalized to other applications as well.by Deepak Narayanan.M. Eng
Digital front end for base-station RF
No full textThe digital front-end (DFE) is the most critical stage in a wireless base-station. The DFE along with the analog to digital converter (ADC) is responsible for bridging the analog RF and IF processing on one side and the digital baseband processing on the other side. The most important reason for replacing analog with digital signal processing is the ability to softly reconfigure the channels in the base station RF in real time, thus allowing for the implementation of various signal conditioning, compensation and mitigation channel non-linear responses. Once tested, these algorithms can be implemented on a proprietary CMOS vector processor and commercial FPGA hardware platforms. In this thesis, we attempt to minimize the design efforts and lower the cost involved in the usage of analog electronics by using sophisticated digital signal processing (DSP) for restoring and enhancing the quality of the wireless channels. This thesis presents a versatile Digital Front-End architecture, which has been simulated using MATLAB/Simulink. The architecture includes the design of robust Digital Up-Conversion (DUC) blocks in the transmit downlink and Digital Down-Conversion (DDC) blocks present in the receiver uplink paths in a wireless base station RF. Crest factor reduction (CFR) schemes help reduce the Peak to Average Power Ratio (PAPR)of the signal entering the base-station and have been implemented widely for code division multiple access (CDMA) and Long Term Evolution (LTE) systems, this is important because if the signal with the high PAPR is allowed to pass through the power amplifier(PA) it will result in the amplifier operating in its nonlinear region creating non-linear distortions in amplitude and phase, and the only other way to avoid this is to back off the signal to the linear region of the amplifier thus reducing its efficiency. The selection and design of the DUC and DDC filters has been compared and optimized to match to the spectral mask requirements mentioned in the 3GPP standards. Crest factor reduction has also been studied in detail and a computationally efficient algorithm for meeting the desired PAPR in accordance with the 3GPP standards will be presented. By using the CFR algorithm, the PAPR of the LTE signal was reduced from 10.8 dB to 7 dB and from 10.5 dB to 8 dB for a WCDMA signal. Finally, we implement Digital Predistortion (DPD) which is a method by which one first stimulates a non-linear power amplifier (PA) with baseband samples and then observes the result of that stimulus at its output. Without this process we will need to use a power amplifier with a higher input power rating which needs to be backed off to operate in its linear region thus reducing the efficiency of the PA used and increasing its cost. The process involves the use of a digital predistorter which creates an expanding nonlinearity which when used in cascade with the PA nullifies the compressing nonlinear characteristics of the PA thus enabling its use in its linear region up to its saturating point. A Look-Up Table (LUT) type Adaptive Digital Pre-Distortion (ADPD) is presented; here we developed an algorithm where the output signal of the PA is used as a reference signal. This reference signal is then used to update the coefficients of the LUT, so that the non-linear responses of the PA will not the affect the amplified signals. In addition, we investigated methods such as the nonlinear auto-regressive moving average (NARMA) and the memory polynomial models. In the latter, the predistorter parameters are calculated from the output signal obtained from the PA through the adaptive functions obtained using the memory polynomial. From these parameters, the predistorted signal is reconstructed and fed to the input of the PA. By using the DPD algorithm the nonlinear distortions of the PA came down by 60 dB when a WCDMA signal was used and by around 40 dB when LTE signal was used. As the PA is the heart of the base-station RF, we show that the main function of the DFE is to ensure a PA linearized output with a high efficiency.M.S.Includes bibliographical referencesby Deepak Gop
Problemas do discurso de Deepak Chopra: uma análise metalinguística de “A cura quântica”
No full textIn this article, our objective is to make some contributions to the debate around the “quantum mysticism” phenomenon, exploring discursive aspects that permeate an utterance with this kind of theme. To this end, we bring forth an analysis of the book Quantum healing by Deepak Chopra, based on the philosophy of the Bakhtin Circle. We investigate not only the author's argumentative strategies, but we also connect the constituent elements of this utterance (theme, structure and style) with its context of publication, production and reception. We end our arguments recognizing the incoherence that Chopra demonstrates with his intertwining of mystical and alternative conceptions with a scientific worldview, while uttering inconsistent metaphors and serious contradictions, but we also highlight that the author was able to influence the way in which concepts related to Quantum Physics circulate outside the academia.Neste artigo, nosso objetivo é contribuir para o debate sobre o misticismo quântico, explorando aspectos discursivos que permeiam um enunciado com tal tema. Para tanto, realizamos uma análise metalinguística do livro A cura quântica de Deepak Chopra, com base na filosofia da linguagem do Círculo de Bakhtin. Investigamos não apenas as estratégias argumentativas do autor, mas também conectamos os elementos constitutivos desse enunciado (tema, estrutura e estilo) com seu contexto de produção e publicação. A partir da análise reconhecemos a incoerência de Chopra ao sintetizar visões de mundo místicas e alternativas e uma visão de mundo científica repleta de metáforas inconsistentes e graves contradições, mas destacando como o autor conseguiu influenciar o modo como conceitos relacionados à Física Quântica são mobilizados fora do contexto acadêmico
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