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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Design and Validation of Configurable Filter for JAS 39 Gripen Mission Planning Data

Flodin, Per January 2009 (has links)
<p>Saab Aerosystems, a part of Saab AB, has the overall responsibility for the development of the fourth generation fighter aircraft JAS 39 Gripen. When planning a mission for one or more aircrafts, a computer program called Mission Support System is used. Some of the data from the planning is then transferred to the actual aircraft. Today there are some unwanted restrictions in the planning software. One of these restrictions is about the fact that a number of parameters that controls the output from a planned mission are not configurable runtime, i.e. a reinstallation at customers location is needed to change this. The main purpose of this thesis was to propose a new design and a new framework that solves the inflexibility described above. The design should also be validated by a test implementation. A number of different designs were proposed and four of these were selected to be candidates for being implemented. An important tool used when developing the designs was the theory of design patterns. To choose one of the four a ranking system, based on both measurable metrics and non-measurable experience, was used. One design was selected to be the best and after implementing of the design it was considered to be valid. Future work can consist of rewriting all modules in the software to use the new framework.</p>
32

Design And Implementation Of A Hybrid And Configurable Access Control Model

Turan, Ugur 01 October 2009 (has links) (PDF)
A hybrid and configurable access control model is designed to satisfy the requirements of using different access control models in the same schema. The idea is arised to completely combine and configure the two main access control models, discretionary and mandatory which have been widely used in many systems so far with their advantages and disadvantages. The motivation originates from the fact that / in real life usage, discretionary based systems needs some strict policies and mandatory based systems needs some flexibility. The model is designed to combine these two appoaches in a single and configurable model, with some required real life extensions, in a conflictfree fashion and configurable degree of combination. Implementation of the model has been done and main important cases which shows the power and expressiveness of the model are designed and implemented. The authorization process is in the responsibility of the model which can be combined with secured authentication and auditing schemas. The new approaches as Role-Based, Context-Based and Temporal access control can easily be embedded in the model due to its generic and modular design.
33

Long-Range, Passive Wireless Monitoring Using Energy-Efficient, Electrically-Small Sensor Nodes and Harmonic Radar Interrogator

Nassar, Ibrahim 01 January 2013 (has links)
This dissertation investigates the use of the harmonic radar technique for passive wireless sensing applications. Issues of DC power consumption, high RF activation power, large node size, and short communication range associated with the existing passive wireless sensing technologies are addressed by the development of novel, completely passive, high efficiency, compact 3-D harmonic sensor nodes. The node transceiver employs a passive frequency doubler to return the second harmonic of the interrogation signal, and electrically-small 3-D antennas to achieve the compactness and high efficiency. The developed nodes fit inside a sphere with a diameter < 3 cm and achieve communication range > 60 m using a 43 dBm EIRP interrogator. Effective modulation is demonstrated experimentally using low cost commercial vibration sensors. To address major challenges associated with long-range, embedded, passive wireless sensing including sensor node identification and remote channel calibration, a 3-D dual-channel transceiver is developed. To the best of the author's knowledge, the presented dual-channel transceiver is the first completely passive design with built-in passive remote channel calibration and identification capabilities, and the presented nodes have the best overall performance among previously published designs, in terms of conversion efficiency, communication range, and occupied volume. To reduce the cost and weight and improve the manufacturing process of the proposed nodes, the 3-D digital additive manufacturing and conformal direct printing technologies are employed. The harmonic interrogator antenna design is also an underlying focus of this work. Different interrogator antenna candidates are developed based on different design approaches. The first approach is based on the use of dual-channel antenna array, where one channel is used for transmission and the second channel is used for reception. Two dual-channel harmonic interrogator antennas that consist of 4-element circular patch antenna arrays and 2-element quasi-Yagi dipole antenna arrays are implemented. The second approach employs mechanically reconfigurable antennas to reduce the size and maintain persistent radiation properties over wide frequency bandwidth. Two mechanical reconfiguration methods are developed; the first method is based on the use of Hoberman's planar foldable linkage to vary the operating frequency of planar circular patch antennas and the second mechanical reconfiguration method is based on the use of a rack and pinion mechanism to reconfigure dual-band slot antennas. The third approach employs a single channel multi-octave Vivaldi antenna to provide the capability to interrogate a large number of harmonic tags that are widely spaced in frequency. To improve the antenna radiation performance over a broad frequency range, a new method based on the introduction of a parasitic elliptical patch in the flare aperture is proposed. This method enables gain and bandwidth improvement compared to what has been reported for Vivaldi antennas with a compact size. To provide the interrogator the capability to steer the radiation beam for locating and tracking sensor nodes, a topology to develop a miniature, non-dispersive switchable 4-bit phase shifter is proposed on the basis of composite right/left handed transmission line unit cells.
34

Pickup and delivery problems with side constraints

Qu, Yuan, Ph. D. 22 February 2013 (has links)
Pickup and delivery problems (PDPs) have been studied extensively in past decades. A wide variety of research exits on both exact algorithms and heuristics for generic variations of the problem as well as real-life applications, which continue to spark new challenges and open up new opportunities for researchers. In this dissertation, we study two variations of pickup and delivery problem that arise in industry and develop new computational methods that are shown to be effective with respect to existing algorithms and scheduling procedures found in practice. The first problem is the pickup and delivery problem with transshipment (PDPT). The work presented here was inspired by a daily route planning problem at a regional air carrier. In structuring the analysis, we describe a unique way to model the transshipment option on a directed graph. With the graph as the foundation, we implemented a branch and price algorithm. Preliminary results showed that it has difficulty in solving large instances. As an alternative, we developed a greedy randomized adaptive search procedure (GRASP) with several novel features. In the construction phase, shipment requests are inserted into routes until all demand is satisfied or no feasible insertion exists. In the improvement phase, an adaptive large neighborhood search algorithm is used to reconstruct portions of the feasible routes. Specialized removal and insertion heuristics were designed for this purpose. We also developed a procedure for generating problem instances in the absence of any in the literature. Testing was done on existing PDP data sets and generated PDPT data set. For the former, the performance and solution quality of the GRASP were comparable to the best known heuristics. For the latter, GRASP found the near optimal solution in most test cases. In the second part of the dissertation, we focus on a new version of the heterogeneous PDP in which the capacity of each vehicle can be modified by reconfiguring its interior to satisfy different types of customer demands. The work was motivated by a daily route planning problem arising at a senior activity center. A fleet of configurable vans is available each day to transport participants to and from the center as well as to secondary facilities for rehabilitative and medical treatment. To find solutions, we developed a two-phase heuristic that makes use of ideas from greedy randomized adaptive search procedures with multiple starts. In phase I, a set of good feasible solutions is constructed using a series of randomized procedures. A representative subset of those solutions is selected as candidates for improvement by solving a max diversity problem. In phase II, an adaptive large neighborhood search (ALNS) heuristic is used to find local optima by reconstructing portions of the feasible routes. Also, a specialized route feasibility check with vehicle type reassignment is introduced to take full advantage of the heterogeneous nature of vehicles. The effectiveness of the proposed methodology is demonstrated by comparing the solutions it provided for the equivalent of several weeks with those that were used in practice and derived manually. The analysis indicates that anywhere from 30% to 40% savings can be achieved with the multi-start ALNS heuristic. An exact method is introduced based on branch and price and cut for settings with more restricted time windows. In the procedure, the master problem at each node in the search tree is solved by column generation to find a lower bound. To improve the bound, subset-row inequalities are applied to the variables of the master problem. Columns are generated by solving the pricing subproblems with a labeling algorithm enhanced by new dominance conditions. Local search on the columns is used to quickly find promising alternatives. Implementation details and ways to improve the performance of the overall procedure are discussed. Testing was done on a set of real instances as well as a set of randomly generated instances with up to 50 customer requests. The results show that optimal solutions are obtained in majority of cases. / text
35

Design and Validation of Configurable Filter for JAS 39 Gripen Mission Planning Data

Flodin, Per January 2009 (has links)
Saab Aerosystems, a part of Saab AB, has the overall responsibility for the development of the fourth generation fighter aircraft JAS 39 Gripen. When planning a mission for one or more aircrafts, a computer program called Mission Support System is used. Some of the data from the planning is then transferred to the actual aircraft. Today there are some unwanted restrictions in the planning software. One of these restrictions is about the fact that a number of parameters that controls the output from a planned mission are not configurable runtime, i.e. a reinstallation at customers location is needed to change this. The main purpose of this thesis was to propose a new design and a new framework that solves the inflexibility described above. The design should also be validated by a test implementation. A number of different designs were proposed and four of these were selected to be candidates for being implemented. An important tool used when developing the designs was the theory of design patterns. To choose one of the four a ranking system, based on both measurable metrics and non-measurable experience, was used. One design was selected to be the best and after implementing of the design it was considered to be valid. Future work can consist of rewriting all modules in the software to use the new framework.
36

Modeling the internet of things in configurable process models / Modélisation de l'internet des objets dans des modèles de processus configurables

Suri, Kunal 11 February 2019 (has links)
Un nombre croissant d’entreprises internationales ont adopté les systèmes d'information centrés-processus pour profiter des avantages de l'utilisation de processus rationalisés basés sur des modèles prédéfinis, également appelés modèles de processus métier. Cependant, l'environnement commercial dynamique actuel exige de la flexibilité et la réutilisation systématique des processus métier, qui se manifeste par l'utilisation de modèles de processus configurables (CPM). Ceci évite le développement de processus à partir de zéro, qui est à la fois une démarche fastidieuse et sujette à de nombreuses erreurs, et facilite le partage d'une famille de variantes de processus métier pouvant être personnalisées en fonction d'exigences métier concrètes. Par ailleurs, l'adoption des ressources de l'Internet des objets (IoT) dans les processus d'entreprise inter-organisationnels est également en croissante constante. Cependant, ces ressources IoT doivent être utilisées efficacement. Ces dispositifs IoT sont hétérogènes en raison de leurs propriétés et de leurs fabricants (normes propriétaires), ce qui pose des problèmes d’interopérabilité. De plus, étant limitées, elles doivent être allouées (et consommées) en gardant à l'esprit des contraintes, tels que le coût énergétique, le coût de calcul, etc. pour éviter les pannes pendant leurs consommations par les processus. Il est donc essentiel de modéliser explicitement la perspective des ressources IoT dans les modèles de processus métiers lors de la phase de conception. Dans la littérature, divers travaux de recherche dans le domaine de gestion des processus métier (BPM) sont généralement axés sur la perspective du flux de contrôle. Bien qu'il existe certaines approches axées sur la perspective des ressources, elles sont généralement dédiées à la perspective des ressources humaines. Ainsi, les travaux sur l'intégration de la perspective des ressources IoT dans les processus métier sont limités pour résoudre des problèmes liés à l'hétérogénéité. De même, dans le contexte des CPM, il n’existe aucune prise en charge de la configuration permettant de modéliser la variabilité des ressources IoT au niveau des CPM. Cette variabilité résulte des fonctionnalités spécifiques aux ressources IoT, telles que la possibilité de partage, et réplication, qui sont pertinentes dans le contexte des processus métier. Dans cette thèse, nous abordons les limitations susmentionnées en proposant une approche pour intégrer la perspective IoT dans le domaine du BPM et soutenir le développement de CPM. Ce travail propose les contributions suivantes: (1) il fournit une description formelle de la perspective des ressources IoT, et de ses relations avec le domaine BPM à l'aide de la technologie sémantique, et (2) il fournit de nouveaux concepts pour permettre l'allocation de ressources IoT configurables dans les CPM. Pour valider notre approche et démontrer sa faisabilité, nous procédons comme suit: (1) implémenter des outils preuve de concept qui soutiennent le développement de processus métier et de modèles de processus configurables conscient des IoT, et (2) réaliser des expérimentations sur des jeux de données de modèles de processus qui démontrent l’efficacité de notre approche et affirment sa faisabilité / On the one hand, a growing number of multi-national organizations have embraced the Process-Aware Information Systems (PAIS) to reap the benefits of using streamlined processes that are based on predefined models, also called as Business Process (BP) models. However, today's dynamic business environment demands flexibility and systematic reuse of BPs, which is provided by the use of Configurable Process Models (CPMs). It avoids the development of processes from scratch, which is both time-consuming and error-prone, and facilitates the sharing of a family of BP variants that can be customized based on concrete business requirements. On the other hand, the adoption of the Internet of Things (IoT) resources in various cross-organizational BPs is also on a rise. However, to attain the desired business value, these IoT resources must be used efficiently. These IoT devices are heterogeneous due to their diverse properties and manufactures (proprietary standards), which leads to issues related to interoperability. Further, being resource-constrained, they need to be allocated (and consumed) keeping in the mind relevant constraints such as energy cost, computation cost, to avoid failures during the time of their consumption in the processes. Thus, it is essential to explicitly model the IoT resource perspective in the BP models during the process design phase. In the literature, various research works in Business Process Management (BPM) domain are usually focused on the control-flow perspective. While there do exist some approaches that focus on the resource perspective, they are typically dedicated to the human resource perspective. Thus, there is limited work on integrating the IoT resource perspective into BPs, without any focus on solving issues related to heterogeneity in IoT domain. Likewise, in the context of CPMs, there is no configuration support to model IoT resource variability at the CPM level. This variability is a result of specific IoT resource features such as Shareability and Replication that is relevant in the context of BPs. In this thesis, we address the aforementioned limitations by proposing an approach to integrate IoT perspective in the BPM domain and to support the development of IoT-Aware CPMs. This work contributes in the following manner: (1) it provides a formal description of the IoT resource perspective and its relationships with the BPM domain using semantic technology and (2) it provides novel concepts to enable configurable IoT resource allocation in CPMs. To validate our approach and to show its feasibility, we do the following: (1) implement proof of concept tools that assist in the development of IoT-aware BPs and IoT-aware CPMs and (2) perform experiments on the process model datasets. The experimentation results show the effectiveness of our approach and affirm its feasibility
37

CONFPROFITT: A CONFIGURATION-AWARE PERFORMANCE PROFILING, TESTING, AND TUNING FRAMEWORK

Han, Xue 01 January 2019 (has links)
Modern computer software systems are complicated. Developers can change the behavior of the software system through software configurations. The large number of configuration option and their interactions make the task of software tuning, testing, and debugging very challenging. Performance is one of the key aspects of non-functional qualities, where performance bugs can cause significant performance degradation and lead to poor user experience. However, performance bugs are difficult to expose, primarily because detecting them requires specific inputs, as well as specific configurations. While researchers have developed techniques to analyze, quantify, detect, and fix performance bugs, many of these techniques are not effective in highly-configurable systems. To improve the non-functional qualities of configurable software systems, testing engineers need to be able to understand the performance influence of configuration options, adjust the performance of a system under different configurations, and detect configuration-related performance bugs. This research will provide an automated framework that allows engineers to effectively analyze performance-influence configuration options, detect performance bugs in highly-configurable software systems, and adjust configuration options to achieve higher long-term performance gains. To understand real-world performance bugs in highly-configurable software systems, we first perform a performance bug characteristics study from three large-scale opensource projects. Many researchers have studied the characteristics of performance bugs from the bug report but few have reported what the experience is when trying to replicate confirmed performance bugs from the perspective of non-domain experts such as researchers. This study is meant to report the challenges and potential workaround to replicate confirmed performance bugs. We also want to share a performance benchmark to provide real-world performance bugs to evaluate future performance testing techniques. Inspired by our performance bug study, we propose a performance profiling approach that can help developers to understand how configuration options and their interactions can influence the performance of a system. The approach uses a combination of dynamic analysis and machine learning techniques, together with configuration sampling techniques, to profile the program execution, analyze configuration options relevant to performance. Next, the framework leverages natural language processing and information retrieval techniques to automatically generate test inputs and configurations to expose performance bugs. Finally, the framework combines reinforcement learning and dynamic state reduction techniques to guide subject application towards achieving higher long-term performance gains.
38

Design and Verification of SOPC FDP2009 and Research of Reconfigurable Applications

Zhang, Fanjiong January 2011 (has links)
In recent years, reconfigurable devices are developing fast because of its flexibility and less development cost. But intrinsic shortcomings of reconfigurable devices, for example, high power, low speed, etc. induce difficulties in complex designs realizations. So people began to consider combination of ASIC (Application-Specific Integrated Circuit) and reconfigurable device on a single chip, which is SOPC (System on Programmable Chip). SOPC can not only decrease development risk and timing to market, but also be used in different applications, especially of products that keep varying, for example, communication and network products. Dynamically reconfiguration means reconfigurable device of the chip can be reconfigured repeatable, and performs different functions at different times. Compared with static reconfiguration, dynamic reconfiguration can use the reconfigurable device more thoroughly. It‟s a hot spot of research in the world, especially in reconfigurable computing. This paper mainly concludes my research work in reconfigurable SOPC in 3 major parts: hardware, software and application. The following works and innovations are completed: 1. SOPC hardware system architecture design and discussion. Helps to define the system architecture and design goals. The design of EBI controller which is used in the SOPC. The integration of the blocks in the system. 2. The building-up of the SOPC system-level verification and block-level verification environment. The set-up of the hardware-software co-simulation environment. The post-layout simulation and formal verification tasks. We propose an innovative automated regression system. The system helps to achieve the same simulation coverage (95%) and the total simulation time is reduced by approximately 30%. 3. SOPC software design, including the OS kernel porting, drivers design and application design. The design of the PowerPC initialization program and UART (Universal Asynchronous Receiver/Transmitter), reconfiguring communication driver programs. Writing the test-cases which are specialized for the system verification and hardware testing. 4. Being the co-designer of the novel bus macro based on the FDP reconfigurable logic core. And we realize the whole reconfigurable system based on this bus macro. 5. The reconfigurable application research based on Reconfigurable Logic Core. The reconfigurable image filter designed implemented on FDP300K Reconfigurable Logic Core device. Using self-design Reconfigurable Logic Core internal bus macro to implement the partial reconfigurable system. The test results showed that the reconfigurable filter has the feature of fast configuration speed and good output image quality.
39

Developing an Automated Explosives Detection Prototype Based on the AS&amp;E 101ZZ System

Arvanitis, Panagiotis Jason 07 October 1997 (has links)
This thesis describes the development of a multi-sensor, multi-energy x-ray prototype for automated explosives detection. The system is based on the American Science and Engineering model 101ZZ x-ray system. The 101ZZ unit received was an early model and lacked documentation of the many specialized electronic components. X-ray image quality was poor. The system was significantly modified and almost all AS&E system electronics bypassed: the x-ray source controller and conveyor belt motor were made computer controllable; the x-ray detectors were re-positioned to provide forward scatter detection capabilities; new hardware was developed to interface to the AS&E pre-amplifier boards, to collect image data from all three x-ray detectors, and to transfer the data to a personal computer. This hardware, the Differential Pair Interface Board (DPIB), is based on a Field Programmable Gate Array (FPGA) and can be dynamically re-configured to serve as a general purpose data collection device in a variety of applications. Software was also developed for the prototype system. A Windows NT device driver was written for the DPIB and a custom bus master DMA collection device. These drivers are portable and can be used as a basis for the development of other Windows NT drivers. A graphical user interface (GUI) was also developed. The GUI automates the data collection tasks and controls all the prototype system components. It interfaces with the image processing software for explosives detection and displays the results. Suspicious areas are color coded and presented to the operator for further examination. / Master of Science
40

Design, Implementation, and Test of Novel Quantum-dot Cellular Automata FPGAs for the beyond CMOS Era

Balijepalli, Heman 09 July 2012 (has links)
No description available.

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