Dissertations / Theses: 'All-data'

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Lipe, Bruce, and Tom Cronauer. "MOBILE ALL TERRAIN TELEMETRY AND DATA DISPLAY VANS." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/606811.

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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada
The 412th Test Wing, Range Division has developed an all-terrain van system to receive real-time telemetry and also to display the processed data for remote location flight-testing. The vans are refurbished Ground Launch Cruise Missile (GLCM), Launch Control Centers (LCC). The vans were a joint development effort between the Range and the Advanced Fighter Technology Integration (AFTI) program office. The van systems were specifically designed to support Ground Collision Avoidance System (GCAS) testing. However, the van systems have been successfully used to support other customers, with remote telemetry needs, due to the systems Commercial Off the Shelf (COTS) design. This document will describe the design, layout and rationale for the systems design. This paper will also provide the systems capabilities with top-level block diagrams.

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2

Fletcher, T. R. "A MIL-STD-1553 Multiplex Data Bus Record-All Small Data Acquisition System." International Foundation for Telemetering, 1992. http://hdl.handle.net/10150/611964.

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International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California
MIL-STD-1553 multiplex data buses are commonly used to link complex software-controlled systems in modern aircraft. The software in these aircraft is routinely updated; each update requires flight testing. Also, sophisticated weapons and electronic warfare systems which are integrated into operationally-ready aircraft must be routinely evaluated. The simplest way to perform the required evaluation is to record all the data from the multiplex data buses during an operational flight; these data can then be replayed and examined after the flight. Traditionally, some operational systems had to be disabled or removed from an aircraft to allow installation of a data acquisition system. This paper discusses a MILSTD- 1553 multiplex bus Record-All Small Data Acquisition System (RASDAS) installed in a McDonnell Douglas CF-188 fighter aircraft to record all data from two 1553 multiplex data buses without displacing any operational equipment. The specific requirements and constraints associated with evaluating the integrated systems of a CF-188 aircraft are examined; further, RASDAS implementation in this aircraft type is discussed from planning to flight evaluation.

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3

Sims, Ruth. "'Design for all' : methods and data to support designers." Thesis, Loughborough University, 2003. https://dspace.lboro.ac.uk/2134/6914.

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If designers are to meet the needs of the growing population of older and disabled people then data on size, shape, posture and capabilities will be increasingly important. This thesis details a methodology for the collection of anthropometry, joint constraints, reach range, postural capability and task specific information, to create a unique database of `individuals'. These data were then used in the development of a computer-based design tool (HADRIAN), to allow design professionals to estimate the percentage of people who could be accommodated by a design. Having complete data sets for individuals is vital to enable multivariate analysis, as opposed to traditional univariate percentile data. Following a review of the literature two interview surveys were conducted with 32 design professionals and 50 older and disabled people. The majority of designers were aware of the philosophy of `design for all', but rarely considered the approach due to perceived time and financial costs. With respect to older and disabled people it was found that nearly all experienced problems completing basic activities of daily life, and that improvements to existing designs could improve quality of life. Activities such as being able to cook a meal, and use the bath were reported as being particularly important. Firstly, a pilot study was conducted with 8 participants to assess the different data collection options. Data were then collected on 100 people, with the majority being older and/or disabled, and encompassing a wide range of capabilities. From these data it was possible to see that the anthropometric data showed a range beyond 15` and 99`h percentile for each dimension when compared to existing anthropometry data, and a breadth of variation in task specific behaviours. Validation trials were then conducted to compare the actual task performance of 10 of the 100 `individuals' with that predicted by HADRIAN, with postures and task capabilities being correctly predicted for open-access reach-and-lift tasks. This gives some confidence that it is possible to predict postures and capabilities from the data collected.

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4

Saridis, Georgios. "Space division multiplexing towards all-optical data centre networks." Thesis, University of Bristol, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.720834.

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Savage, Shelby Jay 1978. "All-optical interferometric switches for data regeneration in fiber optic networks." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40509.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.
Includes bibliographical references.
In the thirty years since the installation of the first fiber optic data link, data rates in installed fiber links have risen from a few Mb/s to tens of Gb/s. In the laboratory, data rates in a single optical fiber have already reached tens of Tb/s. These data rates greatly exceed electronic processing rates, so researchers have turned to all-optical signal processing to achieve many basic network tasks, like wavelength conversion, packet switching, and data regeneration. As data rates increase, the impairments caused by propagation through the glass of optical fiber become worse. Chromatic dispersion causes the temporal broadening of optical bits during propagation, leading to interference between neighboring bits. Nonlinear effects, like the nonlinear index of refraction and four-wave mixing, can cause interference between neighboring wavelength channels. The interaction of dispersion and nonlinearities can lead to variations in the timing of bits and the appearance of optical energy where there had been none. All these effects make 1-bits and 0-bits difficult to distinguish. Today, these distortions are overcome by electronic regenerators. Optical data streams are converted to electrical signals, processed electronically, converted back to an optical signal, and returned to the optical network. In this way, regenerators prevent the accumulation of noise and prevent noise from contributing to the production of more noise. The electronic solution is costly because of the extra hardware required for optical to electrical to optical conversions and performs poorly because of the losses incurred by those conversions. In this thesis, we investigate two regenerators that restore the data quality of ON/OFF keyed data without a conversion of the data to the electrical domain.
(cont..) Both regenerators are based on all-optical switches that take two inputs: the data pulses from the network, and a locally generated clock-pulse train. The all-optical switches then modulate the data pattern onto the clock-pulse train, which becomes the new data stream. The first switch we consider, the WMFUNI, uses the nonlinear properties of fiber to produce the switching action. Using the WMFUNI regenerator, we demonstrate the propagation of 10 Gb/s data over 20,000 km of commercial optical fiber. We also demonstrate the WMFUNI's ability to operate on 40-Gb/s data. Unfortunately, fiber has only a weak nonlinearity, so the WMFUNI is large (~40 cmx40 cm). The second switch uses the much stronger nonlinearity of a semiconductor optical amplifier (SOA). SOA-based switches can be integrated onto chip-scale optics. The switch we test, the SOA-MZI, fits on a ~0.5 cmxl cm chip. Using the SOA-MZI regenerator, we demonstrate the propagation of 10 Gb/s data over 10,000 km of commercial optical fiber. We also show in simulation that the SOA-MZI's operation may be extended to 40 Gb/s.
by Shelby Jay Savage.
Ph.D.

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Hashim, Mashitoh. "New Algorithm and Data Structures for the All Pairs Shortest Path Problem." Thesis, University of Canterbury. Computer Science, 2013. http://hdl.handle.net/10092/8196.

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In 1985, Moffat-Takaoka (MT) algorithm was developed to solve the all pairs shortest path (APSP) problem. This algorithm manages to get time complexity of O(n² log n) expected time when the end-point independent model of probabilistic assumption is used. However, the use of a critical point introduced in this algorithm has made the implementation of this algorithm quite complicated and the running time of this algorithm is difficult to analyze. Therefore, this study introduces a new deterministic algorithm for the APSP that provides an alternative to the existing MT algorithm. The major advantages of this approach compared to the MT algorithm are its simplicity, intuitive appeal and ease of analysis. Moreover, the algorithm was shown to be efficient as the expected running time is the same O(n² log n). Performance of a good algorithm depends on the data structure used to speed up the operations needed by the algorithm such as insert, delete-min and decrease-key operations. In this study, two new data structures have been implemented, namely quaternary and dimensional heaps. In the experiment carried out, the quaternary heap that employed similar concept with the trinomial heap with a special insertion cache function performed better than the trinomial heap when the number of n vertices was small. Likewise, the dimensional heap data structure executed the decrease-key operation efficiently by maintaining the thinnest structure possible through the use of thin and thick edges, far surpassing the existing binary, Fibonacci and 2-3 heaps data structures when a special acyclic graph was used. Taken together all these promising findings, a new improved algorithm running on a good data structure can be implemented to enhance the computing accuracy and speed of todays computing machines.

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Westmore, Matthew Joseph. "Dynamic flat-fielding of BATSE data and the BATSE all-sky survey." Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269934.

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Bozek, Matthew Peter. "Express lanes modification to the data vortex photonic all-optical path interconnection network." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24680.

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Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Wills, D. Scott; Committee Member: Keezer, David; Committee Member: Yalamanchili, Sudhakar

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9

Wang, Jade P. (Jade Peilynn) 1979. "Demonstrating effective all-optical processing in ultrafast data networks using semiconductor optical amplifiers." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44907.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references.
The demand for bandwidth in worldwide data networks continues to increase due to growing Internet use and high-bandwidth applications such as video. All-optical signal processing is one promising technique for providing the necessary capacity and offers payload transparency, power consumption which scales efficiently with increasing bit rates, reduced processing latency, and ultrafast performance. In this thesis, we focus on using semiconductor optical amplifier-based logic gates to address both routing and regeneration needs in ultrafast data networks. To address routing needs, we demonstrate a scalable, multi-packet all-optical header processing unit operating at a line rate of 40 Gb/s. For this experiment, we used the ultrafast nonlinear interferometer (UNI) gate, a discrete optical logic gate which has been demonstrated at speeds of 100 Gb/s for bit-wise switching. However, for all-optical switching to become a reality, integration is necessary to significantly reduce the cost of manufacturing, installation, and operation. One promising integrated all-optical logic gate is the semiconductor optical amplifier Mach-Zehnder interferometer (SOA-MZI). This gate has previously been demonstrated capable of up to 80 Gb/s bit-wise switching operation. To enable simple installation and operation of this gate, we developed a performance optimization method which can quickly and accurately pinpoint the optimal operating point of the switch. This eliminates the need for a time-intensive search over a large parameter space and significantly simplifies the operation of the switch. With this method, we demonstrate the ability of a single SOA-MZI logic gate to regenerate ultrafast pulses over 100 passes and 10,000 km in a regenerative loop. Ultimately, all-optical logic gates must be integrated on a single low-cost platform and demonstrated in cascaded, multi-gate operation for increased functionality.
(cont.) This requires low-loss monolithic integration. Our approach to this involves an asymmetric twin waveguide (ATG) design. This design also has the potential for high-yields as a result of a high tolerance for fabrication errors. We present our characterization results of ATG waveguides and proposals for future improvements.
by Jade P. Wang.
Ph.D.

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10

Zhu, Zhe. "Continuous change detection and classification of land cover using all available Landsat data." Thesis, Boston University, 2013. https://hdl.handle.net/2144/12901.

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Thesis (Ph.D.)--Boston University
Land cover mapping and monitoring has been widely recognized as important for understanding global change and in particular, human contributions. This research emphasizes the use ofthe time domain for mapping land cover and changes in land cover using satellite images. Unlike most prior methods that compare pairs or sets of images for identifying change, this research compares observations with model predictions. Moreover, instead of classifying satellite images directly, it uses coefficients from time series models as inputs for land cover mapping. The methods developed are capable of detecting many kinds of land cover change as they occur and providing land cover maps for any given time at high temporal frequency. One key processing step of the satellite images is the elimination of "noisy" observations due to clouds, cloud shadows, and snow. I developed a new algorithm called Fmask that processes each Landsat scene individually using an object-based method. For a globally distributed set ofreference data, the overall cloud detection accuracy is 96%. A second step further improves cloud detection by using temporal information. The first application ofthe new methods based on time series analysis found change in forests in an area in Georgia and South Carolina. After the difference between observed and predicted reflectance exceeds a threshold three consecutive times a site is identified as forest disturbance. Accuracy assessment reveals that both the producers and users accuracies are higher than 95% in the spatial domain and approximately 94% in the temporal domain. The second application ofthis new approach extends the algorithm to include identification of a wide variety of land cover changes as well as land cover mapping. In this approach, the entire archive of Landsat imagery is analyzed to produce a comprehensive land cover history ofthe Boston region. The results are accurate for detecting change, with producers accuracy of 98% and users accuracies of 86% in the spatial domain and temporal accuracy of 80%. Overall, this research demonstrates the great potential for use of time series analysis of satellite images to monitor land cover change.

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Willems, Fabian. "GhostBuy: An All-Steps Anonymous Purchase Platform (ASAPP) Based on Separation of Data." Thesis, Université d'Ottawa / University of Ottawa, 2005. http://hdl.handle.net/10393/42161.

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In recent years – and especially since the beginning of the COVID-19 pandemic – online shopping has become a part of everyday life for many people. Yet, in contrast to buying at a traditional retail store, staying anonymous is at least difficult if not impossible when shopping online – in particular, when physical goods are to be delivered. From the customer perspective, reasons for seeking anonymity when shopping online can be manifold, for example some do not want anyone to know about their purchases, others do not want their data to be used by Big Data-enabled online retailers. From the point of view of online retailers, the prospect of anonymous online shopping should therefore not only be seen as a threat to their data-driven business models, but also as an opportunity to attract new customers. In this thesis we search and find support in the literature regarding the question whether there is indeed a demand for anonymous online shopping, and we discuss system architecture designs that were proposed by other authors for potentially realizing what we call All-Steps Anonymous Purchase Platforms (ASAPP). We propose a new architecture design that improves earlier work by realizing the concept of Separation of Data within a single platform: GhostBuy. We implement a working prototype of this platform that demonstrates not only the fundamental feasibility of the architecture but also that such a platform can be realized with a look-and-feel similar to that of common online shops. We also propose solutions for certain related aspects that are particularly important in the context of such a platform, as for example a guaranteed use of secure user passwords or application-level database encryption. We evaluate to what extent the proposed architecture and prototype preserve the customers’ anonymity/privacy, showing that the prototype provides it to the maximum possible extent that can be achieved based on the proposed architecture. We also show that the system provides 256-bit security against all but one considered cryptographic and mis-authentication attack vectors and discuss how this can also be achieved for the remaining attack vector. Closing our evaluation, we show how well the platform could presumably be deployed in the real world. Finally, limitations, possible improvements, and potential further future work are discussed and proposed.

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Willems, Fabian. "GhostBuy: An All-Steps Anonymous Purchase Platform (ASAPP) based on Separation of Data." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42161.

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In recent years – and especially since the beginning of the COVID-19 pandemic – online shopping has become a part of everyday life for many people. Yet, in contrast to buying at a traditional retail store, staying anonymous is at least difficult if not impossible when shopping online – in particular, when physical goods are to be delivered. From the customer perspective, reasons for seeking anonymity when shopping online can be manifold, for example some do not want anyone to know about their purchases, others do not want their data to be used by Big Data-enabled online retailers. From the point of view of online retailers, the prospect of anonymous online shopping should therefore not only be seen as a threat to their data-driven business models, but also as an opportunity to attract new customers. In this thesis we search and find support in the literature regarding the question whether there is indeed a demand for anonymous online shopping, and we discuss system architecture designs that were proposed by other authors for potentially realizing what we call All-Steps Anonymous Purchase Platforms (ASAPP). We propose a new architecture design that improves earlier work by realizing the concept of Separation of Data within a single platform: GhostBuy. We implement a working prototype of this platform that demonstrates not only the fundamental feasibility of the architecture but also that such a platform can be realized with a look-and-feel similar to that of common online shops. We also propose solutions for certain related aspects that are particularly important in the context of such a platform, as for example a guaranteed use of secure user passwords or application-level database encryption. We evaluate to what extent the proposed architecture and prototype preserve the customers’ anonymity/privacy, showing that the prototype provides it to the maximum possible extent that can be achieved based on the proposed architecture. We also show that the system provides 256-bit security against all but one considered cryptographic and mis-authentication attack vectors and discuss how this can also be achieved for the remaining attack vector. Closing our evaluation, we show how well the platform could presumably be deployed in the real world. Finally, limitations, possible improvements, and potential further future work are discussed and proposed.

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13

Hockensmith, R. "A Data Handling and Linking System for all of NASA's Near Earth Space Missions." International Foundation for Telemetering, 1987. http://hdl.handle.net/10150/615289.

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International Telemetering Conference Proceedings / October 26-29, 1987 / Town and Country Hotel, San Diego, California
A modularized data handling and linking system is evolving that will meet all of NASA's low earth orbiting space needs. The system is comprised of three major subsystems: (1) Data management (three networks; 300 Mbps to 20 Mbps, 20 Mbps to 3 Mbps, and 3 Mbps to 125 bps); (2) RF (antennas and microwave components); and (3) antenna control. Representative system components, approximately 70% of a total system, have been tested operating through the NASA Tracking and Data Relay Satellite System in May 1987. The modularized concept and data bandwidth transitions of the data management subsystem utilizes recently developed flight components along with developmental models that results in a system that is cost effective with a high level of performance and reliability. The system concept with performance data of key components will be presented.

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14

Hawkins, William Cory. "Evaluation of the Data Vortex Photonic All-Optical Path Interconnection Network for Next-Generation Supercomputers." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14519.

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Todays supercomputers employ the fastest processors incorporating the latest VLSI technology. Unfortunately, usable system performance is often limited by excessive interprocessor latency. To overcome this bottleneck, this thesis explores the use of all-optical path interconnection networks using a new topology defined by Coke Reed [31]. This work overcomes limitations of previous optical networks through a novel use of defection routing to minimize latency and allow more processors to collaborate on the same application and dataset. In this thesis research, the data vortex is formally characterized and tested for performance. Extra angles serve as virtual buffers to provide required system performance, even under asymmetric mode operation. The data vortex is compared to two well-known interconnection networks (omega and butterfly) using metrics of average latency and message acceptance rate. The data vortex is shown to outperform the comparison networks, with a 20-50% higher acceptance rate and comparable average latency. The impact of angle size is also studied, and a new, synchronous mode of operation is proposed where additional angles are added to increase the virtual buffering of the network. The tradeoff between virtual buffering and angle resolution backpressure is explored, and an optimal point is found at the 1:6 I/O to non-I/O (virtual buffering) angle ratio. The new mode and optimal angle count are used to form data vortex networks that perform as well as larger networks with fewer total nodes. Finally, hierarchical layering with data vortex clusters is proposed and compared to a single-level data vortex. In todays technology, similar performance is attained at high network communication locality loads (> 2/3), and a 19% latency reduction is obtained at the highest locality loads (> 95%) for current optical switching technology. For projected future technology, the clustered system is shown to yield up to a 55% reduction in latency for applications with 2/3 or better locality.

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15

Neumann, Bradley C. "Is All Open Space Created Equal? A Hedonic Application within a Data-Rich GIS Environment." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/NeumannBC2005.pdf.

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16

Hawkins, William Cory. "Evaluation of the data vortex photonic all-optical path interconnection network for next-generation supercomputers." Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-12182006-155304/.

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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2007.
Dr. Henry L. Owen III, Committee Member ; Dr. David Keezer, Committee Member ; Dr. D. Scott Wills, Committee Chair.

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Gallagher, Eamon. "All Recessions Are Not Equal: The Effect of Sectoral Shifts on Unemployment Using Regional Data." Scholarship @ Claremont, 2019. https://scholarship.claremont.edu/cmc_theses/2261.

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This thesis investigates the effect that variation in employment between industries has had on the depth of recession faced by Metropolitan Statistical Areas (MSAs) in the United States. This analysis is limited to the previous two national recessions. I use regression analysis to find that increases in variation in employment has a significant effect on the maximum increase in unemployment rate in MSAs after controlling for relevant MSA characteristics. In this framework I also find that increases in education could mitigate the negative effects of this variation. I include several other measures of depth of recession including the fall in economic conditions and length for real GDP to recover to its pre-recession levels. I find that the measure of variation is significant in explaining falls in the economic conditions, but not so in explaining the length it takes for each MSA to recover its real GDP.

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Cook, David B. "Making All The Data Available Some Of The Time In Very Large Telemetry Volume Space Applications." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/607508.

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International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California
What do you do when your downlink telemetry needs outstrip your downlink bandwidth capability? The telemetry needed to support construction and operation of the largest, most complex engineering project ever undertaken, the International Space Station (ISS), already requires utilization of the full capacity of the downlink S-band capacity, yet there are additional systems and capabilities still to be added by NASA and the International Partners. The ISS Command and Telemetry Team has developed a method of swapping packets of telemetry that are intended for special operations, while simultaneously sending essential systems telemetry and less critical telemetry that is needed on a continuous basis. To support this attempt to “make available all of the data at least some of the time” the team developed concepts for grouping telemetry into families that would always be selected as a group and then created a set of metadata associated with these groups. This metadata is pre-defined to support automated selection and scrubbing of telemetry to correspond to major upgrades in the command and control software for the ISS. The new process will at least double the effective S-band downlink bandwidth. It will also provide automated selection, scrubbing, reporting and verification of telemetry selections.

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Wolf, David Peter, and dpwolf@mac com. "Vidgets: The Development and Use of Interactive, Network Based Video Works." RMIT University. Applied Communication, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080617.144959.

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This exegesis looks at interactive, network based video through the development and use of experimental works. The works are described in terms of the concepts, techniques and theories explored and their implications for future works and theory. It documents the formal and technical experiments which were used to investigate the affordances of network based video for real time interaction, and tracks the development of vidgets as audio-visual tools and instruments as they increased in complexity and function, finally being specifically designed for use in live audiovisual (VJ) performances. It explains how ideas originating from the histories of sound art and systems based art as were used as frameworks for conceptualising and developing interactive screen based works. The term 'all-data' is devised as a means to describe both the network based digital environment which these new works inhabit and the expanded palette of digital signals which may be used and inco rporated into the works themselves. Through processes of action research and critical reflection, it identifies and explores a number of techniques and attributes which are common to interactive, network based video production as a practice and which may be used in a range of future projects.

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Li, Alan. "Design of a broadband PLL solution for burst-mode Clock and Data Recovery in all-optical networks." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82612.

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All-Optical networks have been proposed as a solution to meet growing demand for broadband access. An essential component in these networks will be new Clock and Data Recovery devices which can recover burst-mode traffic. This a significantly different challenge from conventional, continuous-mode CDR. Burst-mode data originates at various sources and arrives at the receiver with different phases, potentially changing by +/-pi Rads. Therefore, new CDR designs are required to adapt to large steps in phase upon each new burst to maintain BER integrity. This must be accomplished on the order of ns if All-Optical networks are to be viable. While several such designs have been proposed, a clear solution has yet to emerge. This thesis proposes broadband PLLs as a new solution for burst-mode Clock and Data Recovery. The design of a completed broadband Phase-locked CDR ASIC is presented, from original device modeling to implementation and testing.

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von, Bloh Johannes [Verfasser]. "No size fits all - Exploring Entrepreneurship Measurement using Big Data, rare Events and Ecosystems / Johannes von Bloh." Hannover : Gottfried Wilhelm Leibniz Universität, 2021. http://d-nb.info/123342677X/34.

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Ekanayake, Gemunu. "Determination of Stellar Parameters through the Use of All Available Flux Data and Model Spectral Energy Distributions." UKnowledge, 2017. http://uknowledge.uky.edu/physastron_etds/44.

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Basic stellar atmospheric parameters, such as effective temperature, surface gravity, and metallicity plays a vital role in the characterization of various stellar populations in the Milky Way. The Stellar parameters can be measured by adopting one or more observational techniques, such as spectroscopy, photometry, interferometry, etc. Finding new and innovative ways to combine these observational data to derive reliable stellar parameters and to use them to characterize some of the stellar populations in our galaxy is the main goal of this thesis. Our initial work, based on the spectroscopic and photometric data available in literature, had the objective of calibrating the stellar parameters from a range of available flux observations from far-UV to far-IR. Much effort has been made to estimate probability distributions of the stellar parameters using Bayesian inference, rather than point estimates. We applied these techniques to blue straggler stars (BSSs) in the galactic field, which are thought to be a product of mass transfer mechanism associated with binary stars. Using photometry available in SDSS and GALEX surveys we identified 85 stars with UV excess in their spectral energy distribution (SED) : indication of a hot white dwarf companion to BSS. To determine the parameter distributions (mass, temperature and age) of the WD companions, we developed algorithms that could fit binary model atmospheres to the observed SED. The WD mass distribution peaks at 0.4M , suggests the primary formation channel of field BSSs is Case-B mass transfer, i.e. when the donor star is in red giant phase of its evolution. Based on stellar evolutionary models, we estimate the lower limit of binary mass transfer efficiency β ~ 0.5. Next, we have focused on the Canis Major overdensity (CMO), a substructure located at low galactic latitude in the Milky Way, where the interstellar reddening (E(B-V )) due to dust is significantly high. In this study we estimated the reddening, metallicity distribution and kinematics of the CMO using a sample of red clump (RC) stars. The averageE(B-V)(~0.19)is consistent with that measured from Schlegel maps (Schlegal et.al. 1998). The overall metallicity and kinematic distribution is in agreement with the previous estimates of the disk stars. But the measured mean alpha element abundance is relatively larger with respect to the expected value for disk stars.

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Hui, Yang, Li Shanzhong, and Zhang Qishan. "A PERSONAL TELEMETRY STATION." International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/608571.

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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California
In this paper, a PCM telemetry system based on Personal computer is presented and some important methods that are used to realize the system will be introduced, such as a new kind of all digital PLL bit synchronizer and a way to solve the problem of high-rate data storage. The main idea of ours is to make the basic parts of PCM telemetry system (except receiver) in the form of PC cards compatible with EISA Bus, which forms a telemetry station with resource of PC computer. Finally, a laboratory prototype with rate up to 3.2Mbps is built.

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Arsenovic, Jasenko. "Big Data: A Toll for all Strategic Decisions : A Study of Three Large Food and Beverage Processing Organizations." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Informatik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-28645.

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I will look at what impact big data have had on the managerial strategic decisions in the food and beverage industry. This in order to understand the complexity and theory of organizational strategic management, an effort to define the contemporary strategic theory into a holistic conceptual model is done through a literature review on organizational strategy. This literature explicitly proposes four distinctly different types of strategies that management need to consider in the organizational context. Namely, long-term strategy, internal business strategy, external corporate strategy, and competitive strategy. The study analyzed the food and beverage industry over a decade (2005-2014), where the three of the largest actors in the industry were selected, Nestlé S.A, PepsiCo Inc, and Unilever. The choice of method was content analysis, where three structured categorization matrixes were developed which each analyzed parts of the annual reports. The study propose the role of big data as a strategic tool for managerial decision from a theoretical standpoint. The content analysis show that hypothesis 1, could be confirmed, big data have an impact on all the proposed four managerial strategic decisions. Second hypothesis could not be confirmed, since decentralization does only occur for one of the organizations, but increased external environment turbulence could be concluded for the industry in general. The third hypothesis could be confirmed, which show that there is an increase in individualization due to increased customer involvement and demand. The analysis discovered three distinct time periods during the last decade, namely pre- economic instability period (2005-2007), economic instability period (2008-2011) and finally the post-paradigm period (2012-2014). Where the year 2011 was the most turbulent in terms of economy and technology for the industry. The study clearly show that customers are now involved in the production process, customers are co-creators of the products. There is now a two-way communication and increased social responsibility awareness. This study shows that the old traditional approach of looking at markets in order to position yourself to stay competitive are obsolete as this study predicted. customers demand to be a part of the organizational culture. This conclude that big data is an important tool for all strategic managerial decisions.

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Bullard, González Alfredo, Jara Alejandro Falla, and Barraza Nicole Roldán. "In god we trust, all other bring data. ¿Debe haber un control de fusiones empresariales en el Perú?" THĒMIS-Revista de Derecho, 2012. http://repositorio.pucp.edu.pe/index/handle/123456789/109294.

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En el presente artículo, los autores critican este carácter basado en la incertidumbre del control de fusiones. Exigen que estas agencias se basen más en los hechos y no pretendan corregir errores antes de que sucedan. Además, analizan los resultados del control de fusiones en el Derecho comparado. De este modo, llegan a la conclusión de que dicho control suele ser ineficiente, pues genera costos a las empresas y puede evitar fusiones que, a la larga, serían beneficiosas. En el Perú, la existencia de un Proyecto de Ley para regular las fusiones motiva la crítica de los autores, que ven en esta medida un control innecesario y negativo que traería más problemas que beneficios.

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Bastidas, Oscar H. "Computational All Atom Energy Density Landscape Mappings of Intra-protein Interactions from Static and Dynamic Ensemble Structure Data." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4955.

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Understanding the energetic and dynamic behavior of natural protein fluctuations is critical to elucidating important information associated with a multitude of protein functions including signaling processes, enzyme behavior, aggregation pathways etc... This information is also critically important in the development of novel and effective strategies aimed at target proteins associated with pathologies and disease. In order to obtain such useful information, tools and techniques are lacking that: 1) permit the efficient quantitative analysis of fluctuation behavior of existing protein structure ensembles and 2) permit computationally generated natural fluctuation states of proteins at relatively large timescales demanded by the need for biologically relevant results. This thesis presents such methods as well as the results of their application to a case study of Aβ40 and pathogenic Aβ42 where we identify key differences in energy interactions between those two isoforms. Additionally, our detailed atom-level analysis, was able to identify very minute differences in Ramachandran angles between the two strains as the cause for these interaction energy differences. We also demonstrate the efficacy of our implicit solvent algorithm in recovering independently, experimentally identified domain motion over a variety of protein systems. Such a system that is medically significant is the HIV-1 protease for which we identified significant motion of a flap domain known to be pharmaceutically important to the protease’s active site in drug targeting strategies. Lastly, we employ the insights thus acquired from the Aβ40/42 case study to see if Aβ42 aggregation inhibitors can be rationally developed and then tested in vitro for their efficacy. Results were very promising with Aβ42 aggregate sizes being significantly reduced by statistically significant margins by the inhibitor compounds. Due to these encouraging results, we have consequently obtained a provisional patent application for our inhibitors.

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Parvathareddy, Bhavana. "STATISTICAL ANALYSIS OF INJURY DATA AND THE CONCEPTUAL DESIGN OF A ROLLOVER PROTECTIVE STRUCTURE FOR AN ALL-TERRAIN VEHICLE." UKnowledge, 2005. http://uknowledge.uky.edu/gradschool_theses/347.

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The rising statistics of fatal and non-fatal injuries involving an all-terrain vehicle has called for an analysis of the accumulated data from the past years. The analysis has led to the conclusion that in the past years, the fatal and non-fatal injuries have been rising rapidly in spite of the consent decrees which were brought into effect from 1988-1998 by the consumer product safety commission. A necessity to provide increased safety while riding an all-terrain vehicle is recognized. Rollover protective structures which were used with successful results in curbing the injuries on agricultural tractors have been identified as having a potential to serve the purpose. A conceptual design of an automatically deployable rollover protective structure has been dealt with, in the thesis.

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Humphreys, Betsy P. "The Role of Developmental Screening Practices in Early Diagnosis of Autism Spectrum Disorders| An Analysis of All-Payer Claims Data in New Hampshire." Thesis, The University of North Carolina at Chapel Hill, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3562747.

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Universal developmental screening during pediatric well child care detects early delays in development and is a critical gateway to early intervention for young children at risk for Autism Spectrum Disorders (ASD). Developmental screening practices are highly variable, and few studies have examined screening utilization for children at risk for ASD. Currently, a two to four year gap exists between first recognition of concern and referral for diagnostic evaluation of ASD. The purpose of the current study was to examine the influence of developmental screening practices on timing of ASD diagnoses in the state of New Hampshire through health care administrative claims data from the New Hampshire Comprehensive Health Care Information System. The study examined differences in mean age of ASD diagnosis for a sample of 144 children who were born between January 2007 and December 2010 who received or did not receive universal screening during well child care, as well as those who received screening at multiple time points and those who received screening at one time point. Further, the study examined the association between gender, geographic region and provider type on age at diagnosis of ASD. The data suggested no significant differences in mean age of ASD diagnosis for children who received a standardized developmental screening during well-child care and those who did not. Statistically significant differences in mean age of diagnosis were found between children who were screened at one time point and children who were screened at more than one time point. Children screened at more than one time point were diagnosed later than those screened at one time point. Geographic region was a significant predictor on age of ASD diagnosis accounting for approximately 31% of the variance. Continued efforts to measure screening practices through use of administrative claims data may increase utilization and improve access to intervention for young children at risk for ASD.

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Hall, Kathryn Elizabeth. "All the live-long day : developing time-space maps to structure archaeological and palaeo-environmental data relating to the mesolithic-neolithic transition in southern England." Thesis, University of Cambridge, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709216.

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Shell, Michael David. "Cascaded All-Optical Shared-Memory Architecture Packet Switches Using Channel Grouping Under Bursty Traffic." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4892.

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This work develops an exact logical operation model to predict the performance of the all-optical shared-memory architecture (OSMA) class of packet switches and provides a means to obtain a reasonable approximation of OSMA switch performance within certain types of networks, including the Banyan family. All-optical packet switches have the potential to far exceed the bandwidth capability of their current electronic counterparts. However, all-optical switching technology is currently not mature. Consequently, all-optical switch fabrics and buffers are more constrained in size and can cost several orders of magnitude more than those of electronic switches. The use of shared-memory buffers and/or links with multiple parallel channels (channel grouping) have been suggested as ways to maximize switch performance with buffers of limited size. However, analysis of shared-memory switches is far more difficult than for other commonly used buffering strategies. Obtaining packet loss performance by simulation is often not a viable alternative to modeling if low loss rates or large networks are encountered. Published models of electronic shared-memory packet switches (ESMP) have primarily involved approximate models to allow analysis of switches with a large number of ports and/or buffer cells. Because most ESMP models become inaccurate for small switches, and OSMA switches, unlike ESMP switches, do not buffer packets unless contention occurs, existing ESMP models cannot be applied to OSMA switches. Previous models of OSMA switches were confined to isolated (non-networked), symmetric OSMA switches using channel grouping under random traffic. This work is far more general in that it also encompasses OSMA switches that (1) are subjected to bursty traffic and/or with input links that have arbitrary occupancy probability distributions, (2) are interconnected to form a network and (3) are asymmetric.

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Bröder, Jens [Verfasser], Stefan [Akademischer Betreuer] Blügel, Riccardo [Akademischer Betreuer] Mazzarello, and Christian [Akademischer Betreuer] Linsmeier. "High-throughput all-electron density functional theory simulations for a data-driven chemical interpretation of X-ray photoelectron spectra / Jens Bröder ; Stefan Blügel, Riccardo Mazzarello, Christian Linsmeier." Aachen : Universitätsbibliothek der RWTH Aachen, 2021. http://d-nb.info/1235280756/34.

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32

Cerasale, Mark. "The Effects of Computer-Assisted Repeated Readings on the Reading Performance of Middle School Students with Mild Intellectual Disabilities." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3689.

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The No Child Left Behind Act of 2001 has mandated that all public school students will be reading at grade level by the 2013-2014 school year. Florida has embarked on an agenda to ensure that the kindergarten through high school student population is reading at or above grade level by 2014. Many of Florida's low-performing student population, including middle school students with high incidence disabilities, are reading below grade level. Using a multiple baseline across subjects design, this study examined the impact of computer-assisted repeated readings on the reading performance of three middle school students with mild intellectual disabilities over the course of 67 days. Results showed an improvement in reading fluency rate using instructional level text. The study was evaluated using quality indicators of single-subject research in special education. Future research is advocated to replicate this study across different grades and exceptionalities.
Ed.D.
Department of Child, Family and Community Sciences
Education
Curriculum and Instruction EdD

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33

Shirmohammadi, Bamshad. "All for one one for All." Thesis, Högskolan Dalarna, Mikrodataanalys, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:du-35944.

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Imagine a school where everyone tries to help the weakest student, and there is no competition among them except for being nice and supportive! Or companies who, instead of competing with their customers, try to make the world a better place! Yes, it is too big of a goal, but every big move starts from a small step. The small step in my thesis is working on the question "how to make groups work together in a better way" applied to the world of artificial intelligence. To train virtual agents to successfully work together, one must overcome the same problems humans face, such as selfishness. While agents might not be selfish, we typically optimize or preferentially select them on their individual performance. Thus, the selfish agents would also win again. To study and remedy this problem, I made a game for multiple artificial agents competing with each other. I also devised different objective functions so that selfishness might not be the optimal strategy. Specifically, Darwin's theory of Evolution and the group selection mechanism provides a different mechanism to incentivize groups to cooperate. The idea is that when evolving agents under these conditions, the last generation will include only cooperating agents. I used a framework that includes an evolvable neural network for implementing the agents and a genetic algorithm working based on specific rewarding schemes. I found that different rewarding schemes result in different agent behavior. Specifically, when agents evolve in groups whose performance is measured by their weakest member, they not only evolve to become an effective group, but they receive rewards more equally.

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34

Subramaniam, Suresh. "All-optical networks with sparse wavelength conversion /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/6032.

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35

Khan, Akmal. "Pregnancy related maternal deaths at Salt River Forensic Pathology Laboratory: a 5 year retrospective study of the epidemiological data and spectrum of pathology and disease in all pregnancy related deaths at Salt River Pathology Laboratory irrespect." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/6662.

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Includes abstract.
Includes bibliographical references.
Death of women whilst pregnant and in the post-partum period is a huge burden of disease in South Africa. All confidential enquiries and research into pregnancy related deaths in South Africa have focused on examining the cases based on the WHO definition of maternal death and have excluded deaths from incidental or accidental causes. Pregnancy related deaths due to suicide, homicide and accidental causes have predominantly only been studied in first world countries. There is minimal data available for developing countries like South Africa.

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36

Mokhtar, Ahmed. "Routing, switching, and multiaccess in all-optical networks /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/5942.

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Zhou, Neng-Fa. "What I have learned from all these solver competitions." Universität Potsdam, 2010. http://opus.kobv.de/ubp/volltexte/2010/4143/.

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In this talk, I would like to share my experiences gained from participating in four CSP solver competitions and the second ASP solver competition. In particular, I’ll talk about how various programming techniques can make huge differences in solving some of the benchmark problems used in the competitions. These techniques include global constraints, table constraints, and problem-specific propagators and labeling strategies for selecting variables and values. I’ll present these techniques with experimental results from B-Prolog and other CLP(FD) systems.

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38

Yuan, Xiaochun, and 袁小春. "Routing protocols in all-optical packet switched networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31243885.

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Yuan, Xiaochun. "Routing protocols in all-optical packet switched networks /." Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25100725.

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40

Autry, Chris Brian. "Minimization of jitter in SDH/SONET networks via an all-digital desynchronizer." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/15412.

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41

Berdugo, Albert, and William G. Ricker. "A NEW 1553 ALL-BUS INSTRUMENTATION MONITOR." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613782.

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International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada
Increased data throughput demands in military and avionics systems has led to the development of an advanced, All-Bus MIL-STD-1553 Instrumentation Monitor. This paper discusses an airborne unit which acquires the information from up to 8 dual-redundant buses, and formats the data for telemetry, recording or real-time analysis according to the requirements of IRIG-106-86, Chapter 8. The ALBUS-1553 acquires all or selected 1553 messages which are formatted into IRIG-compatible serial data stream outputs. Data is time tagged to microsecond resolution. The unit selectively transmits entire or partial 1553 messages under program control. This results in reduced transmission bandwidth if prior knowledge of 1553 traffic is known. The ALBUS also encodes analog voice inputs, discrete userword inputs and multiplexed analog (overhead) inputs. The unit is provided in a ruggedized airborne housing utilizing standard ATR packaging,

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42

Yamamoto, Takahiro S. "New method of all-sky searches for continuous gravitational waves." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/264642.

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京都大学
新制・課程博士
博士(理学)
甲第23361号
理博第4732号
新制||理||1679(附属図書館)
京都大学大学院理学研究科物理学・宇宙物理学専攻
(主査)教授田中貴浩, 准教授久徳浩太郎, 教授萩野浩一
学位規則第4条第1項該当
Doctor of Science
Kyoto University
DFAM

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43

Soodla, Johan. "A System for Cross-matching All-sky Surveys." Thesis, Uppsala universitet, Avdelningen för systemteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385772.

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This thesis describes the cross-matching software solution lying at thecore of the computational infrastructure for the VASCO project. The VASCO project has a goal to mine historical all-sky surveys to find astronomical anomalies. It aims to give new clues to either SETI research or in theoretical astrophysics, and serves as a starting point for observational followup and/or new theoretical developments. Cross-matching throughout the thesis refers to comparing billions of astronomical objects recorded in the historical USNO and PanSTARRS allskysurveys. This thesis describes how to approach this huge computational challenge using methods of big data and cloud computing. The techniques described in this thesis resulted in a list of about 400 thousand objects which are usable in further analysis in the machine learning tool called ML-Blink.

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Bergstrom, Peter D. Jr. "Markov chain models for all-optical shared memory packet switches." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/15361.

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45

Bilbeisi, Hana. "Time-slotted scheduling for agile all-photonics networks : performance and complexity." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112558.

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Schedulers in optical switches are still electronic, the performance of these units has a significant impact on the performance of the network and could form a bottleneck in high speed networks, such as AAPN. Four time-slotted scheduling algorithms are investigated in this study, PIM, iSlip, PHM and Adapted-SRA. The study addresses the performance of AAPN for each of the algorithms, and evaluates the hardware complexity, estimating the running time of the algorithms. Performance measures were collected from an OPNET model, designed to emulate AAPN. Furthermore, hardware complexity and timing constraints were evaluated through hardware simulations, for iSlip, and through analysis for the rest of the algorithms. iSlip confirmed its feasibility by meeting the 10us timing constraint set by AAPN. The study revealed the superiority of iSlip and PHM over PIM and Adapted-SRA.

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46

Zhang, Chi. "System Level Modeling and Verification of All-digital Phase-locked Loop." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-175151.

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In wirelesscommunication systems, a local oscillator (LO) aims at demodulating radio-frequency signals into baseband signals. The performance of these signals determines the quality of communications which is highly affected by the phase accuracy of local oscillators. Therefore, evaluating jitter/phase noise should be an essential part when designing wireless communication systems. Typically, LO is achieved by traditional analog PLL. These prototypes have several drawbacks including low integration, narrow bandwidth and high phase noise. With the development of digital techniques, approaches towards an All-digital Phase-Locked Loop have been forwarded against the traditional analogy type. The thesis mainly deals with the modeling and verification of an All-digital Phase-Locked Loop concerning its architecture, functionality and phase noise modeling and analysis. It starts with a comparison of current frequency synthesizers including direct analog/digital synthesis and indirect synthesis using PLL/ADPLL. The advantage and analogy of ADPLL versus traditional PLL in radio-frequency applications has been discussed. In order to gain overall understanding of ADPLL, a behavioral theory in both time and phase domain has been conducted in detail. Analysis shows that the restrictive factors of proposed ADPLL lie in TDC and DCO phase noise. It is also proved that the bandwidth and settling time of ADPLL is determined by proportional and integrating parameter of loop filter. Upon the completion of ADPLL theory analysis, a model based on simulink has been put forward. The phase noise level of TDC is specified and mode switch is implemented in order to improve the speed of ADPLL. The reason for choosing 2nd-order MASH-1-1 type ß¢ modulator is briefly discussed. The phase noise of DCO is generated in time-domain using filtered Gaussian distribution and the free-running DCO achieves -20dB/dec spectrumfrom 10Hz to 500kHz. The results verified the feasibility of proposed ADPLL by achieving -50dBc/Hz in-band noise. Other results including howfractional precision, SDMclock and precision contributed to ADPLL phase noise has been presented. A tradeoff between phase noise shaping quality and settling time was evaluated. Ultimately, global parameters setup for the fulfillment of best performance is demonstrated.

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Gest, Johann. "Discrete fiber Raman amplifiers for agile all-photonic networks." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103199.

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This thesis is dedicated to the study of gain transients of discrete fiber Raman amplifiers and to the all-optical gain-clamping technique which is used to mitigate those transients.
First, we study the standing-wave and the traveling-wave gain-clamping techniques when applied to a single discrete fiber Raman amplifier in the context of WDM channel add and drop. We take into account the operational regime of the amplifier and the location of the surviving channel in the amplification band. We demonstrate that the gain-clamped amplifier has to be operated in a regime below the critical regime to ensure that gain-clamping will be in effect. The efficiency of gain-clamping also depends on the feedback level of the lasing signal and on the implementation.
Next, we investigate the dynamic behaviour of a single discrete fiber Raman amplifier fed by multi-channel packet traffic. Our study shows that the efficiency of the gain-clamping technique to reduce the gain transients is dependent upon the operational regime of the amplifier and the packet duration. However, we also demonstrate that gain-clamping is not required to control the gain transients as the gain variations of the unclamped amplifier are small enough to be neglected.
We then theoretically analyse the dynamic response of cascades of discrete fiber Raman amplifiers subject to WDM channel add and drop. We consider cascades of mixed unclamped and gain-clamped amplifiers, varying the number and the position of the gain-clamped amplifiers in the cascade and taking into account the location of the surviving channel and the operational regime of the amplifiers. Our results show that the location of the gain-clamped amplifiers in a mixed cascade affects the transient characteristics and that it is possible to control the transients within tolerable limits.
Finally, we investigate the gain transients that occur in hybrid amplifiers in the presence of channel add and drop. We demonstrate that the gain-clamping technique can be used to mitigate the gain transients in hybrid amplifiers and that the surviving channel location does not influence the transient characteristics, contrary to the case of single and cascaded fiber Raman amplifiers.

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Wang, Rui. "Gossiping in meshes in all-port mode and with short packets." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37046494.

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Wang, Rui, and 王銳. "Gossiping in meshes in all-port mode and with short packets." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37046494.

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De, Vega Rodrigo Miguel. "Modeling future all-optical networks without buffering capabilities." Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210455.

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In this thesis we provide a model for a bufferless optical burst switching (OBS) and an optical packet switching (OPS) network. The thesis is divided in three parts.

In the first part we introduce the basic functionality and structure of OBS and OPS networks. We identify the blocking probability as the main performance parameter of interest.

In the second part we study the statistical properties of the traffic that will likely run through these networks. We use for this purpose a set of traffic traces obtained from the Universidad Politécnica de Catalunya. Our conclusion is that traffic entering the optical domain in future OBS/OPS networks will be long-range dependent (LRD).

In the third part we present the model for bufferless OBS/OPS networks. This model takes into account the results from the second part of the thesis concerning the LRD nature of traffic. It also takes into account specific issues concerning the functionality of a typical bufferless packet-switching network. The resulting model presents scalability problems, so we propose an approximative method to compute the blocking probability from it. We empirically evaluate the accuracy of this method, as well as its scalability.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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Dissertations / Theses on the topic 'All-data'

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