Thèses : « Office of Space Science and Applications »

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葉慶輝 et Hing-fai Devil Yip. « Applications of neural networks for industrial and office automation ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31243873.

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Yip, Hing-fai Devil. « Applications of neural networks for industrial and office automation / ». Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23555981.

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Behr, Michael K. « State-space multitaper spectrogram algorithms : theory and applications ». Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/107033.

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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 63-67).
I present the state-space multitaper approach for analyzing non-stationary time series. Nonstationary time series are commonly divided into small time windows for analysis, but existing methods lose predictive power by analyzing each window independently, even though nearby windows have similar spectral properties. The state-space multitaper algorithm combines two approaches for spectral analysis: the state-space approach models the relations between nearby windows, and the multitaper approach balances a bias-variance tradeoff inherent in Fourier analysis of finite interval data. I illustrate an application of the algorithm to real-time anesthesia monitoring, which could prevent traumatic cases of intraoperative awareness. I discuss issues including a real-time implementation and modeling the system's noise parameters. I identify the new problem of phase censorship, by which spectral leakage hides some information necessary to relate signal phases across windows in time.
by Michael K. Behr.
M. Eng.

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Ko, Stephen C. « Development of Radiation Shielding Materials for Space Applications ». W&M ScholarWorks, 1997. https://scholarworks.wm.edu/etd/1539626106.

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Yasami, Saeid. « Ultra-Low Power RFIC for Space/Medical/Mobile Applications ». Thesis, University of Louisiana at Lafayette, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10003754.

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State-of-the-arts design, implementation, and optimization of Ultra-Low Power Radio Frequency Integrated Circuits (ULP RFIC) for medical, space, and mobile applications have been proposed. New approximated formulas in modeling of the circuits and systems for CAD development have been suggested which make the computer simulations more accurate. Algorithm optimizations for faster design time and possible automations compared to traditional and manual implementations are also offered that reduce the final release time of the products in a more systematic way. These design methodologies are based on advancements of IC fabrication in scaling to Nano-meter regimes, improvement of powerful software simulation tools especially at high frequencies, and manipulating novel ideas in development phases. Note that these design proposals are not only limited to space, biomedical, and mobile application; as a matter of fact, they can be used in any chip design and development ranging from smart watch to glasses and etc.

To have a comprehensive understanding of wireless system design and circuit implementation requires years of experiences and research on multi-disciplinary areas ranging from semiconductor at physic level, circuit analysis, software programming for simulation, test and automation purposes, architecture level, high frequency and RF behavior of components and many more. That is why it has been said the RF design is challenging and takes more years to become an expert on these areas. There are still huge shortages for RF and Analog engineers due to the challenges throughout the world both in industry and academia.

For the circuits presented in this dissertation, frequencies range from ISM band 2.4GHz for mobile application to 10GHz and 24 GHz in microwave applications. The detail analyses for implementations and simulations have been shown to verify the implementations. Optimizations are presented by extensive analysis and iterative simulations. Solutions and tips to simplify design flows are mentioned throughout the dissertation.

Chapters begin with introductions and motivations; next, detail discussion and investigation are presented in subsequent sections; finally summaries giving at the end of each chapter. At the end of dissertation, the possible future works and research orientation have been proposed.

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Garroway, Diana. « A haptic interface for editing space curves with applications to animation authoring / ». Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82487.

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Animators working with 3D models and data typically are still bound to 2D interaction simply because input devices, such as mice, and display devices, such as graphic screens, are 2D. We present a new multi-modal interface for editing 3D motion data. We explore the use of a haptic device for intuitive input and feedback in 3D. Animators are allowed to create 3D animations in a uniform environment that permits interactive editing of the space curves. In the basic mode, the haptic device guides the hand of the user along a trajectory that was previously specified as an animation. Editing can be accomplished by assigning an elasto-plastic behaviour to the object. This interface provides a simple, intuitive method for one user or several participants to actually experience movement, other than visually, for purposes of creation.

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Gunnarsson, Linnea. « Design Space Exploration for Value Prediction in Security Applications ». Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-409971.

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With the introduction of Spectre and Meltdown, two new attacks thattarget the speculative instructions due to Out-of-Order execution intoday's processors, a new way to handle speculative loads has beenproposed. Instead of performing the speculative load, the approach isto predict them. This is a new way to use value predictors. In thiswork, the Last Value Predictor, which predicts based on the previouslyseen value, Value TAgged GEometric history length Predictor (VTAGE),which predicts based on the global branch history, and a stridepredictor, which predicts with help of strides, has been compared tosee which one has the best fit for this new use. They have been runwith the SPEC CPU 2017 benchmark suite in three different tests,different sizes, different threshold confidence and for VTAGE,different associativity. The VTAGE predictor performed best in terms ofvalues predicted and values correctly predicted. The thresholdconfidence level plays an important role in how many incorrectpredictions were made. The associativity in the VTAGE did not do muchdifference to the results.

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Gassend, Blaise L. P. (Blaise Laurent Patrick) 1978. « A fully microfabricated two-dimensional electrospray array with applications to space propulsion ». Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40313.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 257-269).
This thesis presents the design, fabrication and testing of a fully-integrated planar electrospray thruster array, which could lead to more efficient and precise thrusters for space propulsion applications. The same techniques could be used for making arrays to increase throughput in many other electrospray applications. Electrospray thrusters work by electrostatically extracting and accelerating ions or charged droplets from a liquid surface to produce thrust. Emission occurs from sharp emitter tips, which enhance the electric field and constrain the emission location. The electrospray process limits the thrust from a single tip, so that achieving millinewton thrust levels requires an array with tens of thousands of emitters. Silicon batch microfabrication has been used, as it is well suited for making large arrays of emitters. The thruster is made using Deep Reactive Ion Etching (DRIE) and wafer bonding techniques, in a six mask process, and comprises two components. The emitter die with up to 502 emitters in a 113 mm2 area, is formed using DRIE and SF6 etching, and is plasma treated to transport liquid to the tips in a porous black-silicon surface layer. The extractor die incorporates the extractor electrode, a Pyrex layer for insulation, and springs which are used to reversibly assemble the emitter die. This versatile assembly method, with 10 µm RMS alignment accuracy and 1.3 µm RMSD repeatability, allows the extractor die to be reused with multiple emitter dies, and potentially with different emitter concepts than the one presented. The thruster, weighing 5 g, was tested with the ionic liquids EMI-BF4 and EMIIm. Time of flight measurements show that the thruster operates in the ion emission regime most efficient for propulsion, with a specific impulse around 3000 s at a 1 kV extractor voltage. Emission starts as low as 500 V. Currents of 370 nA per emitter have been recorded at 1500 V, for an estimated thrust of 26 nN per emitter or 13 µN total, and a 275 mW power consumption. The thrust efficiency is estimated around 85%. In good operating conditions, the current intercepted on the extractor electrode is well below 1%, increasing to a few percent at the highest current levels. The beam divergence half width half maximum is between 10 and 15°.
by Blaise Laurent Patrick Gassend.
Ph.D.

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Yuan, Ke. « Inference and learning in state-space point process models : algorithms and applications ». Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/352932/.

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Physiological signals such as neural spikes and heart beats are discrete events in time, driven by a continuous underlying system. A recently introduced data driven model to analyse such systems is the state-space model with point process observations (SSPP), parameters of which and the underlying state sequence are simultaneously identified in a maximum likelihood setting using an approximate expectation-maximization (EM) algorithm. This thesis provides a detailed study on the property of SSPP under the EM setting. The results strongly suggest that the Bayesian treatment is more appropriate to avoid biased estimation. For this we develop the variational methods, and a range of efficient Markov chain Monte Carlo methods. The performance of these inference mechanisms is thoroughly tested on both synthetic and real world datasets.

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Hua, Nan. « Space-efficient data sketching algorithms for network applications ». Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44899.

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Sketching techniques are widely adopted in network applications. Sketching algorithms “encode” data into succinct data structures that can later be accessed and “decoded” for various purposes, such as network measurement, accounting, anomaly detection and etc. Bloom filters and counter braids are two well-known representatives in this category. Those sketching algorithms usually need to strike a tradeoff between performance (how much information can be revealed and how fast) and cost (storage, transmission and computation). This dissertation is dedicated to the research and development of several sketching techniques including improved forms of stateful Bloom Filters, Statistical Counter Arrays and Error Estimating Codes. Bloom filter is a space-efficient randomized data structure for approximately representing a set in order to support membership queries. Bloom filter and its variants have found widespread use in many networking applications, where it is important to minimize the cost of storing and communicating network data. In this thesis, we propose a family of Bloom Filter variants augmented by rank-indexing method. We will show such augmentation can bring a significant reduction of space and also the number of memory accesses, especially when deletions of set elements from the Bloom Filter need to be supported. Exact active counter array is another important building block in many sketching algorithms, where storage cost of the array is of paramount concern. Previous approaches reduce the storage costs while either losing accuracy or supporting only passive measurements. In this thesis, we propose an exact statistics counter array architecture that can support active measurements (real-time read and write). It also leverages the aforementioned rank-indexing method and exploits statistical multiplexing to minimize the storage costs of the counter array. Error estimating coding (EEC) has recently been established as an important tool to estimate bit error rates in the transmission of packets over wireless links. In essence, the EEC problem is also a sketching problem, since the EEC codes can be viewed as a sketch of the packet sent, which is decoded by the receiver to estimate bit error rate. In this thesis, we will first investigate the asymptotic bound of error estimating coding by viewing the problem from two-party computation perspective and then investigate its coding/decoding efficiency using Fisher information analysis. Further, we develop several sketching techniques including Enhanced tug-of-war(EToW) sketch and the generalized EEC (gEEC)sketch family which can achieve around 70% reduction of sketch size with similar estimation accuracies. For all solutions proposed above, we will use theoretical tools such as information theory and communication complexity to investigate how far our proposed solutions are away from the theoretical optimal. We will show that the proposed techniques are asymptotically or empirically very close to the theoretical bounds.

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Yeh, Pen-Shu, et Warner H. Miller. « A REAL-TIME HIGH PERFORMANCE DATA COMPRESSION TECHNIQUE FOR SPACE APPLICATIONS ». International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/608305.

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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada
A high performance lossy data compression technique is currently being developed for space science applications under the requirement of high-speed push-broom scanning. The technique is also error-resilient in that error propagation is contained within a few scan lines. The algorithm is based on block-transform combined with bit-plane encoding; this combination results in an embedded bit string with exactly the desirable compression rate. The lossy coder is described. The compression scheme performs well on a suite of test images typical of images from spacecraft instruments. Hardware implementations are in development; a functional chip set is expected by the end of 2000.

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Viggh, Herbert E. M. « Artificial intelligence applications in teleoperated robotic assembly of the EASE space structure ». Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/39358.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, and Dept. of Electrical Engineering and Computer Science, 1988.
Bibliography: leaf 197.
by Herbert E. M. Viggh.
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, and Dept. of Electrical Engineering and Computer Science, 1988.

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Muggli, Martin D. « Enhancing Space and Time Efficiency of Genomics in Practice through Sophisticated Applications of the FM-Index ». Thesis, Colorado State University, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10977737.

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Genomic sequence data has become so easy to get that the computation to process it has become a bottleneck in the advancement of biological science. A data structure known as the FM-Index both compresses data and allows efficient querying, thus can be used to implement more efficient processing methods. In this work we apply advanced formulations of the FM-Index to existing problems and show our methods exceed the performance of competing tools.

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Tirukkovalur, Sravya. « A Global Address Space Approach to Automated Data Management for Parallel Quantum Monte Carlo Applications ». The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1307464186.

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Vazquez, Ramos Gabriel. « Wireless Power Transfer for Space Applications : System Design and Electromagnetic Compatibility Compliance of Radiated Emissions ». Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5546.

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This dissertation evaluates the possibility of wireless power transfer (WPT) systems for space applications, with an emphasis in launch vehicles (rockets). After performing literature review for WPT systems, it was identified that magnetic resonance provides the more suited set of characteristics for this application. Advanced analysis, simulation and testing were performed to magnetic resonance WPT systems to acquire system performance insight. This was accomplished by evaluating/varying coupling configuration, load effects and magnetic element physical characteristics (i.e. wire material, loop radius, etc.). It was identified by analysis, circuit simulation and testing that the best coupling configuration for this application was series-series and series-shunt with Litz wire loop inductors. The main concern identified for the implementation of these systems for space applications was radiated emissions that could potentially generate electromagnetic interference (EMI). To address this EMI concern, we developed the Electromagnetic Compatibility Radiated Emissions Compliance Design Evaluation Approach for WPT Space Systems. This approach systematically allocates key analyses, simulations and tests procedures to predict WPT EMC compliance to NASA’s EMC standard Mil-Std-461E/F. Three prototype/magnetic elements were successfully assessed by implementing the WPT EMC design approach. The electric fields intensity generated by the WPT prototypes/magnetic elements tested were: 30.02 dB[micro]V/m, 28.90 dB[micro]V/m and 82.13 dB[micro]V/m (requirement limit: 140 dB[micro]V/m). All three prototypes successfully transferred power wirelessly and successfully met the NASA EMC requirements.
ID: 031001541; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Jiann S. Yuan.; Title from PDF title page (viewed August 21, 2013).; Thesis (Ph.D.)--University of Central Florida, 2012.; Includes bibliographical references (p. 140-145).
Ph.D.
Doctorate
Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering

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Gonzalez, Maria. « Electronic Defects of III-V Compound Semiconductor Materials Grown on Metamorphic SiGe Substrates for Photovoltaic Applications ». The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250703650.

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Zhang, Qianyun. « Antenna design with characteristic mode analysis for Internet of Things applications ». Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/44699.

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The TV white space (TVWS) is one of the promising technologies to provide wide coverage, energy effcient and cost effective Internet of Things (IoT) services. However, its low operating frequency and wide bandwidth poses significant challenges to antenna designs. In this thesis, three antennas are developed using the characteristic mode analysis (CMA) for IoT devices operating over the TVWS. First, a very-low profile circular small antenna is transformed from a vertical monopole antenna. The CMA is used to determine the mode to be excited and to design a specific feeding structure. After being printed on Rogers 5880 substrate, the final antenna structure operates at 474 MHz with a V SWR < 2 bandwidth of 2.2 MHz. Its lateral radius is just 5.2% of the wavelength of its resonant frequency. Second, a compact U-shaped printed UWB monopole antenna is proposed to operate over the entire UHF TV spectrum. This antenna measures 0:36 0 0:06 0 0:01 0 where 0 is the wavelength of its lowest operating frequency. Its V SWR < 2 bandwidth is 87.5%, and the UWB behaviour is discussed by the CMA. Third, a novel antenna design method is established on annular ring-shaped structures with modal characteristics revealed by the CMA. Following the proposed method, another UWB antenna is achieved by creating and exciting multiple modes with resonant frequencies distributed across the UHF TV spectrum. All antenna designs are verified thorough simulations and measurements. Furthermore, antennas are also integrated into IoT devices and their system performance is measured under different communication scenarios. The system measurements also verify the good propagation property and the abundant spectrum resource of the TVWS.

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Petit, Antoine. « Robust visual detection and tracking of complex objects : applications to space autonomous rendez-vous and proximity operations ». Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-00931604.

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In this thesis, we address the issue of fully localizing a known object through computer vision, using a monocular camera, what is a central problem in robotics. A particular attention is here paid on space robotics applications, with the aims of providing a unified visual localization system for autonomous navigation purposes for space rendezvous and proximity operations. Two main challenges of the problem are tackled: initially detecting the targeted object and then tracking it frame-by-frame, providing the complete pose between the camera and the object, knowing the 3D CAD model of the object. For detection, the pose estimation process is based on the segmentation of the moving object and on an efficient probabilistic edge-based matching and alignment procedure of a set of synthetic views of the object with a sequence of initial images. For the tracking phase, pose estimation is handled through a 3D model-based tracking algorithm, for which we propose three different types of visual features, pertinently representing the object with its edges, its silhouette and with a set of interest points. The reliability of the localization process is evaluated by propagating the uncertainty from the errors of the visual features. This uncertainty besides feeds a linear Kalman filter on the camera velocity parameters. Qualitative and quantitative experiments have been performed on various synthetic and real data, with challenging imaging conditions, showing the efficiency and the benefits of the different contributions, and their compliance with space rendezvous applications.

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Chaibva, Faith Anesu. « The use of response surface methodology and artificial neural networks for the establishment of a design space for a sustained release salbutamol sulphate formulation ». Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1010432.

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Quality by Design (QbD) is a systematic approach that has been recommended as suitable for the development of quality pharmaceutical products. The QbD approach commences with the definition of a quality target drug profile and predetermined objectives that are then used to direct the formulation development process with an emphasis on understanding the pharmaceutical science and manufacturing principles that apply to a product. The design space is directly linked to the use of QbD for formulation development and is a multidimensional combination and interaction of input variables and process parameters that have been demonstrated to provide an assurance of quality. The objective of these studies was to apply the principles of QbD as a framework for the optimisation of a sustained release (SR) formulation of salbutamol sulphate (SBS), and for the establishment of a design space using Response Surface Methodology (RSM) and Artificial Neural Networks (ANN). SBS is a short-acting ♭₂ agonist that is used for the management of asthma and chronic obstructive pulmonary disease (COPD). The use of a SR formulation of SBS may provide clinical benefits in the management of these respiratory disorders. Ashtalin®8 ER (Cipla Ltd., Mumbai, Maharashtra, India) was selected as a reference formulation for use in these studies. An Ishikawa or Cause and Effect diagram was used to determine the impact of formulation and process factors that have the potential to affect product quality. Key areas of concern that must be monitored include the raw materials, the manufacturing equipment and processes, and the analytical and assessment methods employed. The conditions in the laboratory and manufacturing processes were carefully monitored and recorded for any deviation from protocol, and equipment for assessment of dosage form performance, including dissolution equipment, balances and hardness testers, underwent regular maintenance. Preliminary studies to assess the potential utility of Methocel® Kl OOM, alone and in combination with other matrix forming polymers, revealed that the combination of this polymer with xanthan gum and Carbopol® has the potential to modulate the release of SBS at a specific rate, for a period of 12 hr. A central composite design using Methocel® KlOOM, xanthan gum, Carbopol® 974P and Surelease® as the granulating fluid was constructed to fully evaluate the impact of these formulation variables on the rate and extent of SBS release from manufactured formulations. The results revealed that although Methocel® KlOOM and xanthan gum had the greatest retardant effect on drug release, interactions between the polymers used in the study were also important determinants of the measureable responses. An ANN model was trained for optimisation using the data generated from a central composite study. The efficiency of the network was optimised by assessing the impact of the number of nodes in the hidden layer using a three layer Multi Layer Perceptron (MLP). The results revealed that a network with nine nodes in the hidden layer had the best predictive ability, suitable for application to formulation optimisation studies. Pharmaceutical optimisation was conducted using both the RSM and the trained ANN models. The results from the two optimisation procedures yielded two different formulation compositions that were subjected to in vitro dissolution testing using USP Apparatus 3. The results revealed that, although the formulation compositions that were derived from the optimisation procedures were different, both solutions gave reproducible results for which the dissolution profiles were indeed similar to that of the reference formulation. RSM and ANN were further investigated as possible means of establishing a design space for formulation compositions that would result in dosage forms that have similar in vitro release test profiles comparable to the reference product. Constraint plots were used to determine the bounds of the formulation variables that would result in the manufacture of dosage forms with the desired release profile. ANN simulations with hypothetical formulations that were generated within a small region of the experimental domain were investigated as a means of understanding the impact of varying the composition of the formulation on resultant dissolution profiles. Although both methods were suitable for the establishment of a design space, the use of ANN may be better suited for this purpose because of the manner in which ANN handles data. As more information about the behaviour of a formulation and its processes is generated during the product Iifecycle, ANN may be used to evaluate the impact of formulation and process variables on measureable responses. It is recommended that ANN may be suitable for the optimisation of pharmaceutical formulations and establishment of a design space in line with ICH Pharmaceutical Development [1], Quality Risk Management [2] and Pharmaceutical Quality Systems [3]

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Lu, Qifeng. « Bivariate Best First Searches to Process Category Based Queries in a Graph for Trip Planning Applications in Transportation ». Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/26444.

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With the technological advancement in computer science, Geographic Information Science (GIScience), and transportation, more and more complex path finding queries including category based queries are proposed and studied across diverse disciplines. A category based query, such as Optimal Sequenced Routing (OSR) queries and Trip Planning Queries (TPQ), asks for a minimum-cost path that traverses a set of categories with or without a predefined order in a graph. Due to the extensive computing time required to process these complex queries in a large scale environment, efficient algorithms are highly desirable whenever processing time is a consideration. In Artificial Intelligence (AI), a best first search is an informed heuristic path finding algorithm that uses domain knowledge as heuristics to expedite the search process. Traditional best first searches are single-variate in terms of the number of variables to describe a state, and thus not appropriate to process these queries in a graph. In this dissertation, 1) two new types of category based queries, Category Sequence Traversal Query (CSTQ) and Optimal Sequence Traversal Query (OSTQ), are proposed; 2) the existing single-variate best first searches are extended to multivariate best first searches in terms of the state specified, and a class of new concepts--state graph, sub state graph, sub state graph space, local heuristic, local admissibility, local consistency, global heuristic, global admissibility, and global consistency--is introduced into best first searches; 3) two bivariate best first search algorithms, C* and O*, are developed to process CSTQ and OSTQ in a graph, respectively; 4) for each of C* and O*, theorems on optimality and optimal efficiency in a sub state graph space are developed and identified; 5) a family of algorithms including C*-P, C-Dijkstra, O*-MST, O*-SCDMST, O*- Dijkstra, and O*-Greedy is identified, and case studies are performed on path finding in transportation networks, and/or fully connected graphs, either directed or undirected; and 6) O*- SCDMST is adopted to efficiently retrieve optimal solutions for OSTQ using network distance metric in a large transportation network.
Ph. D.

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Ramraj, Varun. « Exploiting whole-PDB analysis in novel bioinformatics applications ». Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:6c59c813-2a4c-440c-940b-d334c02dd075.

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The Protein Data Bank (PDB) is the definitive electronic repository for experimentally-derived protein structures, composed mainly of those determined by X-ray crystallography. Approximately 200 new structures are added weekly to the PDB, and at the time of writing, it contains approximately 97,000 structures. This represents an expanding wealth of high-quality information but there seem to be few bioinformatics tools that consider and analyse these data as an ensemble. This thesis explores the development of three efficient, fast algorithms and software implementations to study protein structure using the entire PDB. The first project is a crystal-form matching tool that takes a unit cell and quickly (< 1 second) retrieves the most related matches from the PDB. The unit cell matches are combined with sequence alignments using a novel Family Clustering Algorithm to display the results in a user-friendly way. The software tool, Nearest-cell, has been incorporated into the X-ray data collection pipeline at the Diamond Light Source, and is also available as a public web service. The bulk of the thesis is devoted to the study and prediction of protein disorder. Initially, trying to update and extend an existing predictor, RONN, the limitations of the method were exposed and a novel predictor (called MoreRONN) was developed that incorporates a novel sequence-based clustering approach to disorder data inferred from the PDB and DisProt. MoreRONN is now clearly the best-in-class disorder predictor and will soon be offered as a public web service. The third project explores the development of a clustering algorithm for protein structural fragments that can work on the scale of the whole PDB. While protein structures have long been clustered into loose families, there has to date been no comprehensive analytical clustering of short (~6 residue) fragments. A novel fragment clustering tool was built that is now leading to a public database of fragment families and representative structural fragments that should prove extremely helpful for both basic understanding and experimentation. Together, these three projects exemplify how cutting-edge computational approaches applied to extensive protein structure libraries can provide user-friendly tools that address critical everyday issues for structural biologists.

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TU, YI-LUNG, et 杜奕龍. « A Case Study and Measurement of Ice Storage Air Conditioning for Factory/Office Space Applications ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/a7jdgs.

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碩士
國立臺北科技大學
能源與冷凍空調工程系碩士班
105
Ice storage air condition system is more complex as compared with traditional air condition systems and long term operation data are insufficient, this study conducted thorough investigation of ice storage air conditioning system of a factory building with office, including thermal loading simulation in the design phase and real-time monitoring on hourly basis for a full year. Based on test data of full-year real operation, the power consumption cost, initial cost and payback period are compared with traditional air condition system. By using central monitoring system of this building, heat load of every hour in 2015 were recorded. The power consumption and cost of the ice storage system are estimated accurately based on the measured data and the equipment efficiency at various loading, and compared with traditional air condition system. The result indicates that the error between simulation and real test is within 3%. The cost evaluation finds that although the cost of ice storage facilities is NTD 23 million higher than the traditional system, it needs only 3 years to payback. Hence, the ice storage is the right choice.

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Thomson, Leslie Elizabeth Anne. « Information in the Home Office : An Ethnographic Study of Space, Content, Management, and Use ». Thesis, 2010. http://hdl.handle.net/1807/24642.

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Many Library and Information Science (LIS) scholars have long articulated the importance of physical and social settings—the environment—when examining how individuals acquire, store, organize, maintain, dispose of, and use information in one of their home or work lives. Yet, few have raised the question of how these information practices are altered and affected in home office spaces, fused living and working environments that lie at the intersection of the personal and the professional. This thesis resulted from an exploratory, ethnographic research study centred upon describing and analyzing the habits of information management and information use that characterize home office settings—specifically, professional home offices that each serve as their user’s only workplace. It argues that the professional home office differs from both traditional professional offices in corporate or institutional settings and from personal home offices used for non-professional tasks and pursuits. The professional home offices of four printing company account managers provided the field from which data was gathered, collected by way of guided tours, diagramming, photography, interviews, and observation. Findings suggest that information practices in professional home offices are a continual negotiation between the two spheres of household and organization, but that this will not necessarily imply a compromise of one for the other.

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Rieger, Christian. « Sampling Inequalities and Applications ». Doctoral thesis, 2008. http://hdl.handle.net/11858/00-1735-0000-0006-B3B9-0.

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Mergner, Sascha. « Applications of Advanced Time Series Models to Analyze the Time-varying Relationship between Macroeconomics, Fundamentals and Pan-European Industry Portfolios ». Doctoral thesis, 2008. http://hdl.handle.net/11858/00-1735-0000-000D-F159-E.

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Thèses sur le sujet « Office of Space Science and Applications »

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