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Towards a Framework for Static Analysis Based on Points-to InformationEdvinsson, Marcus January 2007 (has links)
<p>Static analysis on source code or binary code retrieves information about a software program. In object-oriented languages, static points-to analysis retrieves information about objects and how they refer to each other. The result of the points-to analysis is traditionally used to perform optimizations in compilers, such as static resolution of polymorphic calls, and dead-code elimination. More advanced optimizations have been suggested specifically for Java, such as synchronization removal and stack-allocation of objects. Recently, software engineering tools using points-to analysis have appeared aiming to help the developer to understand and to debug software. Altogether, there is a great variety of tools that use or could use points-to analysis, both from academia and from industry.</p><p>We aim to construct a framework that supports the development of new and the improvement of existing clients to points-to analysis result. We present two client analyses and investigate the similarities and differences they have. The client analyses are the escape analysis and the side-effects analysis. The similarities refer to data structures and basic algorithms that both depend on. The differences are found in the way the two analyses use the data structures and the basic algorithms. In order to reuse these in a framework, a specification language is needed to reflect the differences. The client analyses are implemented, with shared data-structures and basic algorithms, but do not use a separate specification language.</p><p>The framework is evaluated against three goal criteria, development speed, analysis precision, and analysis speed. The development speed is ranked as most important, and the two latter are considered equally important. Thereafter we present related work and discuss it with respect to the goal criteria.</p><p>The evaluation of the framework is done in two separate experiments. The first experiment evaluates development speed and shows that the framework enables higher development speed compared to not using the framework. The second experiment evaluates the precision and the speed of the analyses and it shows that the different precisions in the points-to analysis are reflected in the precisions of the client analyses. It also shows that there is a trade-off between analysis precision and analysis speed to consider when choosing analysis precision.</p><p>Finally, we discuss four alternative ways to continue the research towards a doctoral thesis.</p>
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A Framework for Software Security Testing and EvaluationDutta, Rahul Kumar January 2015 (has links)
Security in automotive industry is a thought of concern these days. As more smart electronic devices are getting connected to each other, the dependency on these devices are urging us to connect them with moving objects such as cars, buses, trucks etc. As such, safety and security issues related to automotive objects are becoming more relevant in the realm of internet connected devices and objects. In this thesis, we emphasize on certain factors that introduces security vulnerabilities in the implementation phase of Software Development Life Cycle (SDLC). Input invalidation is one of them that we address in our work. We implement a security evaluation framework that allows us to improve security in automotive software by identifying and removing software security vulnerabilities that arise due to input invalidation reasons during SDLC. We propose to use this framework in the implementation and testing phase so that the critical deficiencies of software in security by design issues could be easily addressed and mitigated.
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Static and dynamic performance during precision fine motor trackingGottlich, Samantha 20 November 2013 (has links)
Studies of static and dynamic motor control have a long research history. In most cases, studies have focused on one condition or the other. However, it is important to determine whether differences exist between the two types of task, especially when used in conjunction with task performance. Video game controllers, motorized wheel chairs, steering wheels, and robotic surgical equipment are all examples of how modern equipment uses static and dynamic motor control to achieve task performance goals. To this end, this study aimed to examine possible differences in accuracy or consistency of performance between static and dynamic variations of a precision fine motor tracking task. Nineteen healthy, right-handed volunteer participants were asked to manipulate a cursor to track a moving target with both index fingers, using a static control method in one task and a dynamic control method in another task. The cursor was to follow as closely as possible a target traveling along a diagonal line and back. The control methods were tested during two different testing sessions to reduce confounding of the task conditions. After 50 practice trials in a condition, 5 test trials were recorded. Two dependent variables, RMSE and CVE, were used to represent task performance as indicators of accuracy and consistency, respectively. Analyses of variance with a Latin Square design were used to compare overall performance of each dependent variable between the two conditions. Results showed a significant difference in both variables with p-values less than .001; tracking accuracy was better on the static task and cursor motion consistency was better on the dynamic task. These findings suggest that performance aspects of a fine motor control task does vary with control method and can be used to aid equipment design and task performance in the future. / text
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Advanced Applications of Miniemulsion TechnologyEl-Jaby, Ula 19 April 2010 (has links)
Miniemulsion technology is attracting increasing interest for the preparation of nano-size particles. However, the barrier to industrialising miniemulsion-based products is the lack of an energy efficient and scalable homogenisation device. Current laboratory techniques consist of batch units, however trends are leaning towards developing continuous processes. The objective of the work presented here is to investigate the use of the rotor-stator (RS) and static mixers (SM) as homogenisation devices and ultimately develop a continuous emulsification/polymerisation process for the preparation of miniemulsions.
Initially we investigated the RS as a homogenisation device and found that we were able to generate droplets ranging from 300 nm to 2 μm, at industrially pertinent solids content. Subsequently, we investigated the use of SM and compared their performance in terms of mean droplet size evolutions with the rotor-stator. We were able to generate droplets < 200 nm in size and polymerise them in a stable fashion.
All the available emulsification devices were then compared in terms of power/energy consumption, droplet size distributions and shear rates. It was observed that with energy costs being of similar orders of magnitude, SM imposed less shear, produced relatively narrow distributions and were better adapted to scale-up, making them the optimal choice for miniemulsification.
Energy savings were increased by reducing coalescence during the emulsification step by using in situ generated surfactants, ultimately reducing emulsification time. Neutralising a water-soluble base with an oil-soluble acid almost instantaneously generates in situ surfactants at the oil-water interface. The reduction in emulsification time was partially attributed to the elimination of the relatively slow adsorption step
typical of preformed surfactants.
These results were used to show that emulsifying in situ formulations at moderate flow rates in line with SMX mixers can substantially reduce emulsification time from 30 minutes, with preformed surfactants, to ~30 seconds. With such a rapid emulsification step, it was possible to test the feasibility of the continuous emulsification process followed by polymerisation in a tubular reactor. Comparing this process with a batch operation, similar results for the ratio of NP/ND and conversion were obtained, but the continuous process was accomplished in a single step. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2010-04-19 03:32:08.766
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Static and dynamic response of sandstone masonry units bound with fibre reinforced mortarsIslam, Md Toihidul Unknown Date
No description available.
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Design methodologies for robust low-power digital systems under static and dynamic variationsChae, Kwanyeob 27 August 2014 (has links)
Variability affects the performance and power of a circuit. Along with static variations, dynamic variations, which occur during chip operation, necessitate a safety margin. The safety margin makes it difficult to meet the target performance within a limited power budget. This research explores methodologies to minimize the safety margin, thereby improving the energy efficiency of a system. The safety margin can be reduced by either minimizing the variation or adapting to the variation. This research explores three different methods to compensate for variations efficiently. First, post-silicon tuning methods for minimizing variations in 3D ICs are presented. Design methodologies to apply adaptive voltage scaling and adaptive body biasing to 3D ICs and the associated circuit techniques are explored. Second, non-design-intrusive circuit techniques are proposed for adaptation to dynamic variations. This work includes adaptive clock modulation and bias-voltage generation techniques. Third, design-intrusive methods to eliminate the safety margin are proposed. The proposed methodologies can prevent timing-errors in advance with a minimized performance penalty. As a result, the methods presented in this thesis minimize static variations and adapt to dynamic variations, thereby, enabling robust low-power operation of digital systems.
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Online Child Pornography Offenders and Risk Assessment: How Online Offenders Compare to Contact Offenders Using Common Risk Assessment VariablesMcWhaw, Andrew 06 September 2011 (has links)
The aim of this study was to compare online child pornography offenders and contact offenders along the predictive items of the Static-2002 actuarial risk assessment tool, as well as, several other items and scales predictive of recidivism. In addition, the study wished to determine if the Static-2002 was a well-equipped to assess online offenders. 120 subjects were assessed in this study, 53 online child pornography offenders, 53 child molesters, and 7 offenders who committed both a contact and online offense. The research identified a number of similarities between the two groups of offenders, including a finding that the two groups did not significantly differ in age. The most pronounced differences were found on the several measures of criminality used in the study where contact offenders scored significantly higher. The Static-2002 was found to not be well suited for use with online offenders as the tool had difficulty assessing their sexual deviancy.
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Collection Disjointness Analysis in JavaChu, Hang January 2011 (has links)
This thesis presents a collection disjointness analysis to find disjointness relations between collections in Java. We define the three types of disjointness relations between collections: must-shared, may-shared and not-may-shared. The collection- disjointness analysis is implemented following the way of a forward data-flow analysis using Soot Java bytecode analysis framework. For method calls, which are usually difficult to analyze in static analysis, our analysis provide a way of generating and reading annotations of a method to best approximate the behavior of the calling methods. Finally, this thesis presents the experimental results of the collection-disjointness analysis on several tests.
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Static and dynamic response of sandstone masonry units bound with fibre reinforced mortarsIslam, Md Toihidul 11 1900 (has links)
This research project describes the impact resistance of masonry units bound with fibre-reinforced Type S mortars and hydraulic lime mortar. The dynamic impact factor and stress rate sensitivity were evaluated for the flexural strength of the mortar and the bond strength, and further, the pattern of failure was noted for each mix and loading rate. Results show that the impact resistance of the masonry units increased in the presence of fibres. However, the stress rate sensitivity of the bond strength decreased with an increase in fibre content. Also, whereas the mode of failure in those masonry units bound with plain Type S mortars was through fracture at the mortar-block interface, the addition of fibres transferred the failure plane to within the masonry block. For hydraulic lime mortar, fibre reinforcement retained the sacrificial nature of mortar and also increased the flexural toughness factor of the joint even under dynamic loading. / Structural Engineering
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Fundamental and Third Harmonic Operation of SIT Inverter and its Application to RF Thermal Plasma GenerationUesugi, Y., Imai, T., Kawada, K., Takamura, S. 04 1900 (has links)
No description available.
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