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Articles 2191 - 2220 of 4833

Full-Text Articles in Computer Sciences

Building Iot Based Applications For Smart Cities: How Can Ontology Catalogs Help?, Amelia Gyrard, Antoine Zimmermann, Amit P. Sheth Oct 2018

Building Iot Based Applications For Smart Cities: How Can Ontology Catalogs Help?, Amelia Gyrard, Antoine Zimmermann, Amit P. Sheth

Kno.e.sis Publications

The Internet of Things (IoT) plays an ever-increasing role in enabling smart city applications. An ontology-based semantic approach can help improve interoperability between a variety of IoT-generated as well as complementary data needed to drive these applications. While multiple ontology catalogs exist, using them for IoT and smart city applications require significant amount of work. In this paper, we demonstrate how can ontology catalogs be more effectively used to design and develop smart city applications? We consider four ontology catalogs that are relevant for IoT and smart cities: 1) READY4SmartCities; 2) linked open vocabulary (LOV); 3) OpenSensingCity (OSC); and 4) …


Preferences (Partial Pre-Orders) On Complex Numbers -- In View Of Possible Use In Quantum Econometrics, Songsak Sriboonchitta, Vladik Kreinovich, Olga Kosheleva Oct 2018

Preferences (Partial Pre-Orders) On Complex Numbers -- In View Of Possible Use In Quantum Econometrics, Songsak Sriboonchitta, Vladik Kreinovich, Olga Kosheleva

Departmental Technical Reports (CS)

In economic application, it is desirable to find an optimal solution -- i.e., a solution which is preferable to any other possible solution. Traditionally, the state of an economic system has been described by real-valued quantities such as profit, unemployment level, etc. For such quantities, preferences correspond to natural order between real numbers: all things being equal, the more profit the better, and the smaller unemployment, the better. Lately, it turned out that to adequately describe economic phenomena, it is often convenient to use complex numbers. From this viewpoint, a natural question is: what are possible orders on complex numbers? …


Using Electronic Health Records To Characterize Prescription Patterns: Focus On Antidepressants In Nonpsychiatric Outpatient Settings, Joseph J. Deferio, Tomer T. Levin, Judith Cukor, Samprit Banerjee, Rozan Abdulrahman, Amit P. Sheth, Neel Mehta, Jyotishman Pathak Oct 2018

Using Electronic Health Records To Characterize Prescription Patterns: Focus On Antidepressants In Nonpsychiatric Outpatient Settings, Joseph J. Deferio, Tomer T. Levin, Judith Cukor, Samprit Banerjee, Rozan Abdulrahman, Amit P. Sheth, Neel Mehta, Jyotishman Pathak

Kno.e.sis Publications

Objective

To characterize nonpsychiatric prescription patterns of antidepressants according to drug labels and evidence assessments (on-label, evidence-based, and off-label) using structured outpatient electronic health record (EHR) data. Methods

A retrospective analysis was conducted using deidentified EHR data from an outpatient practice at a New York City-based academic medical center. Structured “medication–diagnosis” pairs for antidepressants from 35 325 patients between January 2010 and December 2015 were compared to the latest drug product labels and evidence assessments. Results

Of 140 929 antidepressant prescriptions prescribed by primary care providers (PCPs) and nonpsychiatry specialists, 69% were characterized as “on-label/evidence-based uses.” Depression diagnoses were associated …


Review Of: Families At Play: Connecting And Learning Through Video Games, Matthew Murray Oct 2018

Review Of: Families At Play: Connecting And Learning Through Video Games, Matthew Murray

Library Faculty Research

No abstract provided.


Poster: Privacy-Preserving Boosting With Random Linear Classifiers, Sagar Sharma, Keke Chen Oct 2018

Poster: Privacy-Preserving Boosting With Random Linear Classifiers, Sagar Sharma, Keke Chen

Kno.e.sis Publications

We propose SecureBoost, a privacy-preserving predictive modeling framework, that allows service providers (SPs) to build powerful boosting models over encrypted or randomly masked user submit- ted data. SecureBoost uses random linear classifiers (RLCs) as the base classifiers. A Cryptographic Service Provider (CSP) manages keys and assists the SP’s processing to reduce the complexity of the protocol constructions. The SP learns only the base models (i.e., RLCs) and the CSP learns only the weights of the base models and a limited leakage function. This separated parameter holding avoids any party from abusing the final model or conducting model-based attacks. We evaluate …


Orecchio: Extending Body-Language Through Actuated Static And Dynamic Auricular Postures, Da-Yuan Huang, Teddy Seyed, Jun Gong, Zhihao Yao, Yuchen Jiao, Xiang Anthony Chen, Xing-Dong Yang Oct 2018

Orecchio: Extending Body-Language Through Actuated Static And Dynamic Auricular Postures, Da-Yuan Huang, Teddy Seyed, Jun Gong, Zhihao Yao, Yuchen Jiao, Xiang Anthony Chen, Xing-Dong Yang

Dartmouth Scholarship

In this paper, we propose using the auricle – the visible part of the ear – as a means of expressive output to extend body language to convey emotional states. With an initial exploratory study, we provide an initial set of dynamic and static auricular postures. Using these results, we examined the relationship between emotions and auricular postures, noting that dynamic postures involving stretching the top helix in fast (e.g., 2Hz) and slow speeds (1Hz) conveyed intense and mild pleasantness while static postures involving bending the side or top helix towards the center of the ear were associated with intense …


Exploiting The Interdependency Of Land Use And Mobility For Urban Planning, Kasthuri Jayarajah, Andrew Tan, Archan Misra Oct 2018

Exploiting The Interdependency Of Land Use And Mobility For Urban Planning, Kasthuri Jayarajah, Andrew Tan, Archan Misra

Research Collection School Of Computing and Information Systems

Urban planners and economists alike have strong interest in understanding the inter-dependency of land use and people flow. The two-pronged problem entails systematic modeling and understanding of how land use impacts crowd flow to an area and in turn, how the influx of people to an area (or lack thereof) can influence the viability of business entities in that area. With cities becoming increasingly sensor-rich, for example, digitized payments for public transportation and constant trajectory tracking of buses and taxis, understanding and modelling crowd flows at the city scale, as well as, at finer granularity such as at the neighborhood …


Inferring Trip Occupancies In The Rise Of Ride-Hailing Services, Meng-Fen Chiang, Ee-Peng Lim, Wang-Chien Lee, Tuan-Anh Hoang Oct 2018

Inferring Trip Occupancies In The Rise Of Ride-Hailing Services, Meng-Fen Chiang, Ee-Peng Lim, Wang-Chien Lee, Tuan-Anh Hoang

Research Collection School Of Computing and Information Systems

The knowledge of all occupied and unoccupied trips made by self-employed drivers are essential for optimized vehicle dispatch by ride-hailing services (e.g., Didi Dache, Uber, Lyft, Grab, etc.). However, the occupancy status of vehicles is not always known to the service operators due to adoption of multiple ride-hailing apps. In this paper, we propose a novel framework, Learning to INfer Trips (LINT), to infer occupancy of car trips by exploring characteristics of observed occupied trips. Two main research steps, stop point classification and structural segmentation, are included in LINT. In the stop point classification step, we represent a vehicle trajectory …


An Evaluation Of Geotagged Twitter Data During Hurricane Irma Using Sentiment Analysis And Topic Modeling For Disaster Resilience, Ike Robert Vayansky Oct 2018

An Evaluation Of Geotagged Twitter Data During Hurricane Irma Using Sentiment Analysis And Topic Modeling For Disaster Resilience, Ike Robert Vayansky

Electronic Theses and Dissertations

Disasters require quick response times, thought-out preparations, overall community, and government support. These efforts will ensure prevention of loss of life and reduce possible damages. The United States has been battered by multiple major hurricanes in the recent years and multiple avenues of disaster response efforts were being tested. Hurricane Irma can be recognized as the most popular hurricane in terms of social media attention. Irma made landfall in Florida as a Category 4 storm and preparation measures taken were intensive thus providing a good measure to evaluate in terms of efficacy. The effectiveness of the response methods utilized are …


Unearthing The X-Streams: Visualizing Water Contamination, Akangsha Bandalkul, Angad Srivastava, Kishan Bharadwaj Shridhar, Jason Guan Jie Ong, Yanrong Zhang Oct 2018

Unearthing The X-Streams: Visualizing Water Contamination, Akangsha Bandalkul, Angad Srivastava, Kishan Bharadwaj Shridhar, Jason Guan Jie Ong, Yanrong Zhang

Research Collection School Of Computing and Information Systems

The datasets released for VAST 2018 Mini Challenge 2 pertain to sensor readings capturing chemical concentrations and physical properties from water bodies in the Boonsong Lekagul wildlife preserve. This challenge is in continuation to the VAST 2017 Challenge, where the company Kasios was identified as the culprit in dumping the chemical - Methylosmoline. In the absence of actual chemical measurements in the soil, challenge participants need to visualize chemical contamination based on the proximal water bodies to identify trends of interest. A horizon plot developed helps to narrow down the complete list of 106 chemicals provided to only 7, …


Traffic-Cascade: Mining And Visualizing Lifecycles Of Traffic Congestion Events Using Public Bus Trajectories, Agus Trisnajaya Kwee, Meng-Fen Chiang, Philips Kokoh Prasetyo, Ee-Peng Lim Oct 2018

Traffic-Cascade: Mining And Visualizing Lifecycles Of Traffic Congestion Events Using Public Bus Trajectories, Agus Trisnajaya Kwee, Meng-Fen Chiang, Philips Kokoh Prasetyo, Ee-Peng Lim

Research Collection School Of Computing and Information Systems

As road transportation supports both economic and social activities in developed cities, it is important to maintain smooth traffic on all highways and local roads. Whenever possible, traffic congestions should be detected early and resolved quickly. While existing traffic monitoring dashboard systems have been put in place in many cities, these systems require high-cost vehicle speed monitoring instruments and detect traffic congestion as independent events. There is a lack of low-cost dashboards to inspect and analyze the lifecycle of traffic congestion which is critical in assessing the overall impact of congestion, determining the possible the source(s) of congestion and its …


Using Chronicling America’S Images To Explore Digitized Historic Newspapers & Imagine Alternative Futures, Elizabeth Lorang, Leen-Kiat Soh Sep 2018

Using Chronicling America’S Images To Explore Digitized Historic Newspapers & Imagine Alternative Futures, Elizabeth Lorang, Leen-Kiat Soh

University of Nebraska-Lincoln Libraries: Presentations

This presentation situates the work of the Aida team broadly as well as hinges this work on some very specific challenges for digital libraries. In doing so demonstrate the many types of questions and domains to be explored in digitized newspapers.


Building Classifiers With Gmdh For Health Social Networks (Bd Askapatient), John Cardiff, Liliya Akhtyamova, Mikhail Alexandrov Sep 2018

Building Classifiers With Gmdh For Health Social Networks (Bd Askapatient), John Cardiff, Liliya Akhtyamova, Mikhail Alexandrov

Conference Papers

Health social media offer useful data for patients and doctors concerning both various medicines and treatments. Usually, these data are accompanied by their assessments in 5- star scale. But such a detail classification has small usefulness because patients and doctors, first of all, want to know about negative cases and to study in detail the extreme ones. In the paper we build classifiers of texts just for these cases using combined classes as negative, all others and worst, satisfactory, best. For this, we study possibilities of different GMDH-based algorithms and compare them with the results of other methods. The selection …


Implicit Linking Of Food Entities In Social Media, Wen Haw Chong, Ee Peng Lim Sep 2018

Implicit Linking Of Food Entities In Social Media, Wen Haw Chong, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Dining is an important part in people’s lives and this explains why food-related microblogs and reviews are popular in social media. Identifying food entities in food-related posts is important to food lover profiling and food (or restaurant) recommendations. In this work, we conduct Implicit Entity Linking (IEL) to link food-related posts to food entities in a knowledge base. In IEL, we link posts even if they do not contain explicit entity mentions. We first show empirically that food venues are entity-focused and associated with a limited number of food entities each. Hence same-venue posts are likely to share common food …


Accurate And Cost-Effective Traffic Information Acquisition Using Adaptive Sampling: Centralized And V2v Schemes, Shiau Hong Lim, Yeow Khiang Chia, Laura Wynter Sep 2018

Accurate And Cost-Effective Traffic Information Acquisition Using Adaptive Sampling: Centralized And V2v Schemes, Shiau Hong Lim, Yeow Khiang Chia, Laura Wynter

Research Collection School Of Computing and Information Systems

The new generation of GPS-based tolling systems allow for a much higher degree of road sensing than has been available up to now. We propose an adaptive sampling scheme to collect accurate real-time traffic information from large-scale implementations of on-board GPS-based devices over a road network. The goal of the system is to minimize the transmission costs over all vehicles while satisfying requirements in the accuracy and timeliness of the traffic information obtained. The system is designed to make use of cellular communication as well as leveraging additional technologies such as roadside units equipped with WiFi and vehicle-to-vehicle (V2V) dedicated …


Teaching Basic Programming To Pre-University Students Through Blended Learning Pedagogy: A Descriptive Study, Vandana Ramachandra Rao, Ngee Mok Heng Sep 2018

Teaching Basic Programming To Pre-University Students Through Blended Learning Pedagogy: A Descriptive Study, Vandana Ramachandra Rao, Ngee Mok Heng

Research Collection School Of Computing and Information Systems

Students enrolling for undergraduate programmes in Singapore would have either finished their polytechnic diploma or completed Junior College (JC) studies. Most pre-university students coming through the JC pathway are not exposed to programming as computing is offered as a subject in a very few JCs. The authors of this paper conducted four runs of an introductory programing course between 2016 and 2017 for a research project funded by the Ministry of Education, Singapore. The project named “Let’s Code!” was intended to introduce fundamental programming concepts to students and guide them to consider taking a computer-science related degree for their university …


Diversity In Online Advertising: A Case Study Of 69 Brands On Social Media, Jisun An, Ingmar Weber Sep 2018

Diversity In Online Advertising: A Case Study Of 69 Brands On Social Media, Jisun An, Ingmar Weber

Research Collection School Of Computing and Information Systems

Lack of diversity in advertising is a long-standing problem. Despite growing cultural awareness and missed business opportunities, many minorities remain under- or inappropriately represented in advertising. Previous research has studied how people react to culturally embedded ads, but such work focused mostly on print media or television using lab experiments. In this work, we look at diversity in content posted by 69 U.S. brands on two social media platforms, Instagram and Facebook. Using face detection technology, we infer the gender, race, and age of both the faces in the ads and of the users engaging with ads. Using this dataset, …


Transferring Time-Series Discrete Choice To Link-Based Route Choice In Space: Estimating Vehicle Type Preference Using Recursive Logit Model, Fabian Bastin, Yan Liu, Cinzia Cirillo, Tien Mai Sep 2018

Transferring Time-Series Discrete Choice To Link-Based Route Choice In Space: Estimating Vehicle Type Preference Using Recursive Logit Model, Fabian Bastin, Yan Liu, Cinzia Cirillo, Tien Mai

Research Collection School Of Computing and Information Systems

This paper considers a sequential discrete choice problem in a time domain, formulated and solved as a route choice problem in a space domain. Starting from a dynamic specification of time-series discrete choices, we show how it is transferrable to link-based route choices that can be formulated by a finite path choice multinomial logit model. This study establishes that modeling sequential choices over time and in space are equivalent as long as the utility of the choice sequence is additive over the decision steps, the link-specific attributes are deterministic, and the decision process is Markovian. We employ the recursive logit …


Digital Forensics In The Next Five Years, Laoise Luciano, Ibrahim Baggili, Mateusz Topor, Peter Casey, Frank Breitinger Aug 2018

Digital Forensics In The Next Five Years, Laoise Luciano, Ibrahim Baggili, Mateusz Topor, Peter Casey, Frank Breitinger

Electrical & Computer Engineering and Computer Science Faculty Publications

Cyber forensics has encountered major obstacles over the last decade and is at a crossroads. This paper presents data that was obtained during the National Workshop on Redefining Cyber Forensics (NWRCF) on May 23-24, 2017 supported by the National Science Foundation and organized by the University of New Haven. Qualitative and quantitative data were analyzed from twenty-four cyber forensics expert panel members. This work identified important themes that need to be addressed by the community, focusing on (1) where the domain currently is; (2) where it needs to go and; (3) steps needed to improve it. Furthermore, based on the …


I Know What You Did Last Summer: Your Smart Home Internet Of Things And Your Iphone Forensically Ratting You Out, Gokila Dorai, Shiva Houshmand, Ibrahim Baggili Aug 2018

I Know What You Did Last Summer: Your Smart Home Internet Of Things And Your Iphone Forensically Ratting You Out, Gokila Dorai, Shiva Houshmand, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

The adoption of smart home Internet of Things (IoT) devices continues to grow. What if your devices can snitch on you and let us know where you are at any given point in time? In this work we examined the forensic artifacts produced by Nest devices, and in specific, we examined the logical backup structure of an iPhone used to control a Nest thermostat, Nest Indoor Camera and a Nest Outdoor Camera. We also integrated the Google Home Mini as another method of controlling the studied Smart Home devices. Our work is the primary account for the examination of Nest …


Discrete Information Object Analysis Of Primary Flight Display Clutter, Kenneth Ward Aug 2018

Discrete Information Object Analysis Of Primary Flight Display Clutter, Kenneth Ward

National Training Aircraft Symposium (NTAS)

Modern aircraft utilize digital display screens to provide critical flight and system status information to pilots. As computing power has increased, the number of data sources and information presented has also increased, with the goal of increasing situational awareness. However, the display can become cluttered with extraneous or irrelevant information, to the detriment of pilot cognitive workload. Pilot perceptions of clutter vary with flight experience, introducing unique considerations in the flight training environment, given the experience difference between instructors and students. Researchers have studied the problem, identifying both the number of visual objects and information density as predictors of perception …


Forensic Analysis Of Immersive Virtual Reality Social Applications: A Primary Account, Ananya Yarramreddy, Peter Gromkowski, Ibrahim Baggili Aug 2018

Forensic Analysis Of Immersive Virtual Reality Social Applications: A Primary Account, Ananya Yarramreddy, Peter Gromkowski, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

Our work presents the primary account for exploring the forensics of immersive Virtual Reality (VR) systems and their social applications. The Social VR applications studied in this work include Bigscreen, Altspace VR, Rec Room and Facebook Spaces. We explored the two most widely adopted consumer VR systems: the HTC Vive and the Oculus Rift. Our tests examined the efficacy of reconstructing evidence from network traffic as well as the systems themselves. The results showed that a significant amount of forensically relevant data such as user names, user profile pictures, events, and system details may be recovered. We anticipate that this …


Welcoming Remarks From The Ijcic Honorary Editor, Peter Grabosky Aug 2018

Welcoming Remarks From The Ijcic Honorary Editor, Peter Grabosky

International Journal of Cybersecurity Intelligence & Cybercrime

No abstract provided.


The Present And Future Of Cybercrime, Cyberterrorism, And Cybersecurity, Kyung-Shick Choi, Claire Seungeun Lee Aug 2018

The Present And Future Of Cybercrime, Cyberterrorism, And Cybersecurity, Kyung-Shick Choi, Claire Seungeun Lee

International Journal of Cybersecurity Intelligence & Cybercrime

Cybercriminology combines knowledge from criminology, psychology, sociology, computer science, and cybersecurity to provide an in-depth understanding of cybercrime. Cybercrime and cybersecurity are interconnected across many places, platforms, and actors. Cybercrime issues are continuously and expeditiously changing and developing, especially with the advent of new technologies. The International Journal of Cybersecurity Intelligence and Cybercrime (IJCIC) aims to contribute to the growing field of cybercriminology and cybersecurity. The IJCIC is eager to work with scholars, policy analysts, practitioners, and others to enhance theory, methods, and practice within cybercrime and cybersecurity at the regional, national, and international levels.


Juvenile Hackers: An Empirical Test Of Self-Control Theory And Social Bonding Theory, Sinchul Back, Sadhika Soor, Jennifer Laprade Aug 2018

Juvenile Hackers: An Empirical Test Of Self-Control Theory And Social Bonding Theory, Sinchul Back, Sadhika Soor, Jennifer Laprade

International Journal of Cybersecurity Intelligence & Cybercrime

In accordance with a similar growth in information technology, computer hacking has become a pervasive issue as a form of crime worldwide in recent years. Self-control theory and social bonding theory have frequently been employed to explain various types of crimes, but rarely to explore computer hacking. Drawing from Gottfredson and Hirschi’s (1990) self-control theory and Hirschi’s (1969) social bonding theory, the purpose of this study is to empirically examine the suitability of these two theories in explaining juvenile computer hacking offenses. The self-report survey data utilized for the present study was derived from middle school and high school students …


Architecture Of Aggression In Cyberspace. Testing Cyber Aggression In Young Adults In Hungary, Katalin Parti, Tibor Kiss, Gergely Koplányi Aug 2018

Architecture Of Aggression In Cyberspace. Testing Cyber Aggression In Young Adults In Hungary, Katalin Parti, Tibor Kiss, Gergely Koplányi

International Journal of Cybersecurity Intelligence & Cybercrime

In order to test whether and how violence is exacerbated in online social networking sites, we utilized the BryantSmith Aggression Scale (Bryant & Smith, 2001), and included examples in the questionnaire offering solutions for 7 different hypothetical cases occurring online (Kiss, 2017). The questionnaire was sent to social work and law school students in Hungary. Prevalence and levels of aggression and its manifestation as violence online proved to be not more severe than in offline social relations. Law students were more aware than students of social work that online hostile acts are discrediting. Students of social work were significantly more …


An Argument For Interdisciplinary Programs In Cybersecurity, Dennis Giever Aug 2018

An Argument For Interdisciplinary Programs In Cybersecurity, Dennis Giever

International Journal of Cybersecurity Intelligence & Cybercrime

In this commentary Dr. Giever presents a compelling argument for interdisciplinary programs in cybersecurity at the university level. He argues that we no longer have the luxury of allowing barriers to exist between those tasked with IT security and those who provide physical security. He recommends that any security program take an “all possible paths” or “balanced approach” to the protection of assets within an organization. Students in computer science, criminal justice, business, human resources, and others should work collaboratively within education programs learning these necessary skills. A team effort is needed to accomplish the myriad of tasks necessary to …


Theatrical Genre Prediction Using Social Network Metrics, Manisha Shukla Aug 2018

Theatrical Genre Prediction Using Social Network Metrics, Manisha Shukla

Graduate Theses and Dissertations

With the emergence of digitization, large text corpora are now available online that provide humanities scholars an opportunity to perform literary analysis leveraging the use of computational techniques. This work is focused on applying network theory concepts in the field of literature to explore correlations between the mathematical properties of the social networks of plays and the plays’ dramatic genre, specifically how well social network metrics can identify genre without taking vocabulary into consideration. Almost no work has been done to study the ability of mathematical properties of network graphs to predict literary features. We generated character interaction networks of …


Spreading Propaganda In Cyberspace: Comparing Cyber-Resource Usage Of Al Qaeda And Isis, Kyung-Shick Choi, Claire Seungeun Lee, Robert Cadigan Aug 2018

Spreading Propaganda In Cyberspace: Comparing Cyber-Resource Usage Of Al Qaeda And Isis, Kyung-Shick Choi, Claire Seungeun Lee, Robert Cadigan

International Journal of Cybersecurity Intelligence & Cybercrime

Terrorists in cyberspace are increasingly utilizing social media to promote their ideologies, recruit new members, and justify terrorist attacks and actions. This study explores the ways in which types of social media, message contents, and motives for spreading propaganda take shape in cyberspace. In order to empirically test these relations, we created a dataset with annual terrorism reports from 2011 to 2016. In our global cyberterrorism dataset, we used and connected cyber-resources (Facebook, online forum, Twitter mentions, websites, and YouTube videos) and legal documents of individual cases that were mentioned in the reports. The results show that YouTube videos were …


Offline Versus Online: A Meaningful Categorization Of Ties For Retweets, Felicia Natali, Feida Zhu Aug 2018

Offline Versus Online: A Meaningful Categorization Of Ties For Retweets, Felicia Natali, Feida Zhu

Research Collection School Of Computing and Information Systems

With the recent proliferation of news being shared through online social networks, it is crucial to determine how news is spread and what drives people to share certain stories. In this paper, we focus on the social networking site Twitter and analyse user’s retweets. We study retweeting patterns between offline and online friends, particularly, how tweet novelty and tweet topic differ between tweets retweeted by offline friends and those retweeted by online friends.