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Full-Text Articles in Physical Sciences and Mathematics

Impacts Of U.S. Biofuels Mandates On Environmental And Energy Security, Mohammad Alshawaf Dec 2013

Impacts Of U.S. Biofuels Mandates On Environmental And Energy Security, Mohammad Alshawaf

Graduate Doctoral Dissertations

Congress passed the Energy Policy Act of 2005 and the Energy Independence and Security Act (EISA) of 2007 to reduce dependency on foreign oil by increasing the use of biofuels. EISA mandates 36 billion gallons of biofuel production in 2022, representing an increase of 118% in eight years. Existing and new farmland are expected to be employed to produce corn and other feedstock necessary to fulfill the biofuel mandate. There is little research on the potential environmental impact on water resources of meeting the ESIA biofuel mandates.

The objectives of this EISA study were twofold. First, the study measured the …


An Access Control Model For Nosql Databases, Motahera Shermin Dec 2013

An Access Control Model For Nosql Databases, Motahera Shermin

Electronic Thesis and Dissertation Repository

Current development platforms are web scale, unlike recent platforms which were just network scale. There has been a rapid evolution in computing paradigm that has created the need for data storage as agile and scalable as the applications they support. Relational databases with their joins and locks influence performance in web scale systems negatively. Thus, various types of non-relational databases have emerged in recent years, commonly referred to as NoSQL databases. To fulfill the gaps created by their relational counter-part, they trade consistency and security for performance and scalability. With NoSQL databases being adopted by an increasing number of organizations, …


Improved Kernel Security Through Code Validation, Diversification, And Minimization, Dannie Michael Stanley Oct 2013

Improved Kernel Security Through Code Validation, Diversification, And Minimization, Dannie Michael Stanley

Open Access Dissertations

The vast majority of hosts on the Internet, including mobile clients, are running one of three commodity, general-purpose operating system families. In such operating systems the kernel software executes at the highest processor privilege level. If an adversary is able to hijack the kernel software then by extension he has full control of the system. This control includes the ability to disable protection mechanisms and hide evidence of compromise.

The lack of diversity in commodity, general-purpose operating systems enables attackers to craft a single kernel exploit that has the potential to infect millions of hosts. If enough variants of the …


The Security And Privacy Implications Of Energy-Proportional Computing, Shane S. Clark Sep 2013

The Security And Privacy Implications Of Energy-Proportional Computing, Shane S. Clark

Open Access Dissertations

The parallel trends of greater energy-efficiency and more aggressive power management are yielding computers that inch closer to energy-proportional computing with every generation. Energy-proportional computing, in which power consumption scales closely with workload, has unintended side effects for security and privacy. Saving energy is an unqualified boon for computer operators, but it is becoming easier to identify computing activities by observing power consumption because an energy-proportional computer reveals more about its workload.

This thesis demonstrates the potential for system-level power analysis---the inference of a computers internal states based on power observation at the "plug." It also examines which hardware components …


Forensic Analysis Of Whatsapp On Android Smartphones, Neha S. Thakur Aug 2013

Forensic Analysis Of Whatsapp On Android Smartphones, Neha S. Thakur

University of New Orleans Theses and Dissertations

Android forensics has evolved over time offering significant opportunities and exciting challenges. On one hand, being an open source platform Android is giving developers the freedom to contribute to the rapid growth of the Android market whereas on the other hand Android users may not be aware of the security and privacy implications of installing these applications on their phones. Users may assume that a password-locked device protects their personal information, but applications may retain private information on devices, in ways that users might not anticipate. In this thesis we will be concentrating on one such application called 'WhatsApp', a …


Dynamic Near Field Communication Pairing For Wireless Sensor Networks, Steven Charles Cook Jul 2013

Dynamic Near Field Communication Pairing For Wireless Sensor Networks, Steven Charles Cook

Theses and Dissertations

Wireless sensor network (WSN) nodes communicate securely using pre-installed cryptographic keys. Although key pre-installation makes nodes less expensive, the technical process of installing keys prevents average users from deploying and controlling their own WSNs. Wireless pairing enables users to set up WSNs without pre-installing keys, but current pairing techniques introduce numerous concerns regarding security, hardware expense, and usability. This thesis introduces dynamic Near Field Communication (NFC) pairing, a new pairing technique designed for WSNs. This pairing overcomes the limitations of both key pre-installation and current pairing techniques. Dynamic NFC pairing is as secure as using pre-installed keys, requires only inexpensive …


Transiently Powered Computers, Benjamin Ransford May 2013

Transiently Powered Computers, Benjamin Ransford

Open Access Dissertations

Demand for compact, easily deployable, energy-efficient computers has driven the development of general-purpose transiently powered computers (TPCs) that lack both batteries and wired power, operating exclusively on energy harvested from their surroundings.

TPCs' dependence solely on transient, harvested power offers several important design-time benefits. For example, omitting batteries saves board space and weight while obviating the need to make devices physically accessible for maintenance. However, transient power may provide an unpredictable supply of energy that makes operation difficult. A predictable energy supply is a key abstraction underlying most electronic designs. TPCs discard this abstraction in favor of opportunistic computation that …


A Secure And Fair Resource Sharing Model For Community Clouds, Santhosh S. Anand May 2013

A Secure And Fair Resource Sharing Model For Community Clouds, Santhosh S. Anand

Graduate Theses and Dissertations

Cloud computing has gained a lot of importance and has been one of the most discussed segment of today's IT industry. As enterprises explore the idea of using clouds, concerns have emerged related to cloud security and standardization. This thesis explores whether the Community Cloud Deployment Model can provide solutions to some of the concerns associated with cloud computing. A secure framework based on trust negotiations for resource sharing within the community is developed as a means to provide standardization and security while building trust during resource sharing within the community. Additionally, a model for fair sharing of resources is …


Software Techniques To Reduce The Energy Consumption Of Low-Power Devices At The Limits Of Digital Abstractions, Mastooreh Salajegheh Feb 2013

Software Techniques To Reduce The Energy Consumption Of Low-Power Devices At The Limits Of Digital Abstractions, Mastooreh Salajegheh

Open Access Dissertations

My thesis explores the effectiveness of software techniques that bend digital abstractions in order to allow embedded systems to do more with less energy. Recent years have witnessed a proliferation of low-power embedded devices with power ranges of few milliwatts to microwatts. The capabilities and size of the embedded systems continue to improve dramatically; however, improvements in battery density and energy harvesting have failed to mimic a Moore's law. Thus, energy remains a formidable bottleneck for low-power embedded systems.

Instead of trying to create hardware with ideal energy proportionality, my dissertation evaluates how to use unconventional and probabilistic computing that …


Utilizing Cyber Espionage To Combat Terrorism, Gary Adkins Jan 2013

Utilizing Cyber Espionage To Combat Terrorism, Gary Adkins

Open Access Theses & Dissertations

The world has effectively exited the Industrial Age and is firmly planted in the Information Age. Global communication at the speed of light has been a great asset to both businesses and private citizens. However, there is a dark side to the age we live in, where terrorist groups are able to communicate, plan, fund, recruit, and spread their message to the world. The relative anonymity the internet provides hinders law enforcement and security agencies in not only locating would-be terrorists but also in disrupting their operations. The internet is a loosely knit group of computers and routers and is …


Defining And Preventing Code-Injection Attacks, Donald Ray Jan 2013

Defining And Preventing Code-Injection Attacks, Donald Ray

USF Tampa Graduate Theses and Dissertations

This thesis shows that existing definitions of code-injection attacks (e.g., SQL-injection attacks) are flawed. The flaws make it possible for attackers to circumvent existing mechanisms, by supplying code-injecting inputs that are not recognized as such. The flaws also make it possible for benign inputs to be treated as attacks. After describing these flaws in conventional definitions of code-injection attacks, this thesis proposes a new definition, which is based on whether the symbols input to an application get used as (normal-form) values in the application's output. Because values are already fully evaluated, they cannot be considered ``code'' when injected. This simple …


Assessing The Role Of User Computer Self-Efficacy, Cybersecurity Countermeasures Awareness, And Cybersecurity Skills Toward Computer Misuse Intention At Government Agencies, Min Suk Choi Jan 2013

Assessing The Role Of User Computer Self-Efficacy, Cybersecurity Countermeasures Awareness, And Cybersecurity Skills Toward Computer Misuse Intention At Government Agencies, Min Suk Choi

CCE Theses and Dissertations

Cybersecurity threats and vulnerabilities are causing substantial financial losses for governments and organizations all over the world. Cybersecurity criminals are stealing more than one billion dollars from banks every year by exploiting vulnerabilities caused by bank users' computer misuse. Cybersecurity breaches are threatening the common welfare of citizens since more and more terrorists are using cyberterrorism to target critical infrastructures (e.g., transportation, telecommunications, power, nuclear plants, water supply, banking) to coerce the targeted government and its people to accomplish their political objectives. Cyberwar is another major concern that nations around the world are struggling to get ready to fight. It …


Application Of A Layered Hidden Markov Model In The Detection Of Network Attacks, Lawrence Taub Jan 2013

Application Of A Layered Hidden Markov Model In The Detection Of Network Attacks, Lawrence Taub

CCE Theses and Dissertations

Network-based attacks against computer systems are a common and increasing problem. Attackers continue to increase the sophistication and complexity of their attacks with the goal of removing sensitive data or disrupting operations. Attack detection technology works very well for the detection of known attacks using a signature-based intrusion detection system. However, attackers can utilize attacks that are undetectable to those signature-based systems whether they are truly new attacks or modified versions of known attacks. Anomaly-based intrusion detection systems approach the problem of attack detection by detecting when traffic differs from a learned baseline. In the case of this research, the …


Physical Unclonable Function Techniques Applied For Digital Hardware Protection, Anthony Barrera Jan 2013

Physical Unclonable Function Techniques Applied For Digital Hardware Protection, Anthony Barrera

Dissertations and Theses

"Privacy is an important property that is growing harder to keep as people develop new ways to steal information from users on their computers. Software alone cannot ensure privacy since an infected system is untrustworthy. This paper presents several challenges malware brings that can be solved by using an external processor. Techniques such as keystroke encryption and message authentication can be used to protect users from having their passwords and other private data stolen. To take advantage of the external hardware, a physical unclonable function can be used to generate private keys without the need for storing them in memory. …


Exploiting Human Factors In User Authentication, Payas Gupta Jan 2013

Exploiting Human Factors In User Authentication, Payas Gupta

Dissertations and Theses Collection (Open Access)

Our overarching issue in security is the human factor – and dealing with it is perhaps one of the biggest challenges we face today. Human factor is often described as the weakest part of a security system and users are often described as the weakest link in the security chain. In this thesis, we focus on two problems which are caused by human factors in user authentication and propose respective solutions. a) Secrecy information inference attack – publicly available information can be used to infer some secrecy information about the user. b) Coercion attack – where an attacker forces a …


Opacity Of Discrete Event Systems: Analysis And Control, Majed Mohamed Ben Kalefa Jan 2013

Opacity Of Discrete Event Systems: Analysis And Control, Majed Mohamed Ben Kalefa

Wayne State University Dissertations

The exchange of sensitive information in many systems over a network can be manipulated

by unauthorized access. Opacity is a property to investigate security and

privacy problems in such systems. Opacity characterizes whether a secret information

of a system can be inferred by an unauthorized user. One approach to verify security

and privacy properties using opacity problem is to model the system that may leak confidential

information as a discrete event system. The problem that has not investigated

intensively is the enforcement of opacity properties by supervisory control. In other

words, constructing a minimally restrictive supervisor to limit the system's …


Ensuring Application Specific Security, Privacy And Performance Goals In Rfid Systems, Farzana Rahman Jan 2013

Ensuring Application Specific Security, Privacy And Performance Goals In Rfid Systems, Farzana Rahman

Dissertations (1934 -)

Radio Frequency IDentification (RFID) is an automatic identification technology that uses radio frequency to identify objects. Securing RFID systems and providing privacy in RFID applications has been the focus of much academic work lately. To ensure universal acceptance of RFID technology, security and privacy issued must be addressed into the design of any RFID application. Due to the constraints on memory, power, storage capacity, and amount of logic on RFID devices, traditional public key based strong security mechanisms are unsuitable for them. Usually, low cost general authentication protocols are used to secure RFID systems. However, the generic authentication protocols provide …