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2009

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Articles 7051 - 7080 of 7616

Full-Text Articles in Physical Sciences and Mathematics

Unusual Anatomy Of The Ectoparasitic Muricid Vitularia Salebrosa (King And Broderip, 1832) (Neogastropoda: Muricidae) From The Pacific Coast Of Panama, Luiz R. L. Simone, Gregory S. Herbert, Didier Merle Jan 2009

Unusual Anatomy Of The Ectoparasitic Muricid Vitularia Salebrosa (King And Broderip, 1832) (Neogastropoda: Muricidae) From The Pacific Coast Of Panama, Luiz R. L. Simone, Gregory S. Herbert, Didier Merle

School of Geosciences Faculty and Staff Publications

The morphology and anatomy of Vitularia salebrosa, a muricid ectoparasitic on other mollusks, are investigated based on study of specimens from western Panama. Distinctive characters of this species include the small size of the buccal mass and radular apparatus, simplification of the odontophore muscles and diminished lateral teeth of the radula; an elongated, narrow proboscis; narrow digestive tract and a differentiable glandular region at the beginning of the posterior esophagus. These traits are consistent with adaptive specialization for an ectoparasitic life history

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Extremely Slow Feeding In A Tropical Drilling Ectoparasite, Vitularia Salebrosa (King And Broderip, 1832) (Gastropoda: Muricidae), On Molluscan Hosts From Pacific Panama, Gregory S. Herbert, Gregory P. Dietl, Helena Fortunato, Luiz R. L. Simone, Jennifer Leigh Sliko Jan 2009

Extremely Slow Feeding In A Tropical Drilling Ectoparasite, Vitularia Salebrosa (King And Broderip, 1832) (Gastropoda: Muricidae), On Molluscan Hosts From Pacific Panama, Gregory S. Herbert, Gregory P. Dietl, Helena Fortunato, Luiz R. L. Simone, Jennifer Leigh Sliko

School of Geosciences Faculty and Staff Publications

This study documents one of the slowest feeding behaviors ever recorded for a muricid gastropod in one of the most biotically rigorous regions on the planet. In Pacific Panama, Vitularia salebrosa attacks mollusks by drilling through their shells. The duration of attacks estimated by isotope sclerochronology of oyster shells collected during attacks in progress ranges from 90 to 230 days, while experimental observation of interactions documented one attack greater than 103 days. The prolonged nature of attacks suggests that V. salebrosa is best characterized as an ectoparasite than as a predator, which is the ancestral condition in the Muricidae. An …

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Enabling Context-Aware Applications In Smart Environments‏, Roman Arora Jan 2009

Enabling Context-Aware Applications In Smart Environments‏, Roman Arora

Computer Science and Engineering Theses

Recognizing human activities is an important feature for the development of contextaware applications that are so fundamental to enabling assistive environments. Only once these applications are able to determine the activities that their inhabitants are performing can they assist the individuals and their special needs. In order to do this, it is necessary to build models that can accurately capture and recognize the observed patterns. Equally important is the need to manage and distribute the information that has been inferred, and to provide Quality of Service (QoS) guarantees so that context-aware applications can react effectively to emergent situations. In this …

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Query Auditing Against Partial Disclosure, Mayur Motgi Jan 2009

Query Auditing Against Partial Disclosure, Mayur Motgi

Computer Science and Engineering Theses

Many government agencies, businesses, and nonprofit organizations need to collect, analyze, and report data about individuals in order to support their short-term and long-term planning activities. Statistical Databases therefore contain confidential information such as income, credit ratings, type of disease, or test scores of individuals. Such data are typically stored online and analyzed using sophisticated database management systems (DBMS) and software packages. On one hand, such database systems are expected to satisfy user requests of aggregate statistics related to non-confidential and confidential attributes. On the other hand, the system should be secure enough to guard against a user's ability to …

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Peon: Privacy-Enhanced Opportunistic Networks With Applications In Assistive Environments, Gauri Vakde Jan 2009

Peon: Privacy-Enhanced Opportunistic Networks With Applications In Assistive Environments, Gauri Vakde

Computer Science and Engineering Theses

Opportunistic Networking holds a great deal of potential for making communications easier and more flexible in pervasive assistive environments. However, security and privacy must be addressed to make these communications acceptable with respect to protecting patient privacy. We propose Privacy-Enhanced Opportunistic Networking (PEON), a system for using opportunistic networking in privacy-preserving way. PEON uses concepts from anonymous communications, re-routing messages through groups of peer nodes to hide the relation between the sources and destinations. We describe a set of protocols that explore a practical range of trade-offs between privacy and communication costs by modifying how closely the protocol adheres to …

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Web Application Integration Using Mashups, Ronda Hilton Jan 2009

Web Application Integration Using Mashups, Ronda Hilton

Computer Science and Engineering Theses

The HTML DOM is the W3C standard data model for HTML documents. A web page may be viewed as a tree structure with data nodes at each level, according to the HTML DOM, to enable web applications to access it dynamically. If a web page mashes up more than one web application, the data from one web application may flow as input into another. The user may manually transfer such data piecemeal by using the mouse to cut and paste the displayed text. Instead of this tedious and error-prone repetitious method of data transfer, the mashup may contain a software …

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Design And Analysis Of Application Architecture For Opportunistic Networks Using Ad Hoc Wi-Fi, Sankalp Vinod Shere Jan 2009

Design And Analysis Of Application Architecture For Opportunistic Networks Using Ad Hoc Wi-Fi, Sankalp Vinod Shere

Computer Science and Engineering Theses

In recent years, the number of smartphone users has increased by many folds. In fact, it is estimated to reach 100 million by 2013. Current generation of smartphones has better storage, battery, computing capabilities and they come equipped with short range communication technologies like Bluetooth and Wi-Fi. These improved capabilities coupled with staggering rise in number of users, has prompted growing interest in smartphone applications that help users to communicate with each other directly and over the internet. In particular as a result, when a large number of mobile users can communicate directly with each other during opportunistic contacts when …

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Pseudo-Hierarchical Ant-Based Clustering Using A Heterogeneous Agent Hierarchy And Automatic Boundary Formation, Jeremy Bernard Brown Jan 2009

Pseudo-Hierarchical Ant-Based Clustering Using A Heterogeneous Agent Hierarchy And Automatic Boundary Formation, Jeremy Bernard Brown

Computer Science and Engineering Theses

The behavior and self-organization of ant colonies has been widely studied and served as the inspiration and source of many swarm intelligence models and related clustering algorithms. Unfortunately, most models that directly mimic ants produce too many clusters and converge too slowly. A wide range of research has attempted to address this issue through various means, but a number of problems remain: 1) Ants must still physically move from one cluster to another through intermediate locations, 2) current methods for remote relocation of an item only consider one movement at time to a particular location and do not consider patterns …

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Reactive Control Composition For Mobile Manipulators, Binu George Mathew Jan 2009

Reactive Control Composition For Mobile Manipulators, Binu George Mathew

Computer Science and Engineering Theses

A mobile manipulator is a manipulator mounted on a mobile platform. Due to this combination it has increased mobility compared to a fixed manipulator and increased dexterity compared to a mobile platform. At the same time it has a significantly higher number of degrees of freedom than fixed manipulators or mobile platforms and an increased task and workspace. In particular, the size of the workspace of the manipulator is restricted only by the workspace limitations of the mobile platform and the obstacles around the goal location. In addition, the extra degrees of freedom increase the number of ways in which …

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Design And Analysis Of A Mobile File Sharing System For Opportunistic Networks, Gautam Ravendra Chavan Jan 2009

Design And Analysis Of A Mobile File Sharing System For Opportunistic Networks, Gautam Ravendra Chavan

Computer Science and Engineering Theses

In the past several years, wireless mobile devices with advanced computing, sensing, and storing capabilities have been increasingly developed by handset manufacturers, deployed by wireless carriers, and accepted by consumers. A prominent example is the vast success of Apple's iPhone, which witnessed a sale of 1 million units during the first 3 days of sales for its new version iPhone 3GS. As a result of the increasing popularity of these mobile devices, users can carry, utilize, and exchange information embedded therein, ideally wherever they go and whenever they want. A prominent scenario is where information is exchanged among users when …

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The Reputation System For Robust, Structured P2p Systems, Apurv Ashok Dhadphale Jan 2009

The Reputation System For Robust, Structured P2p Systems, Apurv Ashok Dhadphale

Computer Science and Engineering Theses

Structured peer-to-peer systems are distributed communication systems that typically use Distributed Hash Table (DHT) indexing to efficiently locate the resources. These networks are highly scalable and can route the messages correctly even for the extremely dynamic environment. But these networks are vulnerable; even a small fraction of malicious nodes can bias the lookup results when they are present on a lookup path. In our thesis, we address this problem of reliably searching the insecure p2p networks. We propose a reputation system to reduce the number of failed lookups and make the networks more robust. For our study, the concept is …

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Liquid: A Detection Resistant Covert Timing Channel Based On Ipd Shaping, Robert J. Walls Jan 2009

Liquid: A Detection Resistant Covert Timing Channel Based On Ipd Shaping, Robert J. Walls

Computer Science and Engineering Theses

Covert timing channels provide a way to surreptitiously leak information from an entity in a higher-security level to an entity in a lower level. The difficulty of detecting or eliminating such channels makes them a desirable choice for adversaries that value stealth over throughput. When one considers the possibility of such channels transmitting information across network boundaries, the threat becomes even more acute. A promising technique for detecting covert timing channels focuses on using entropy-based tests. This method is able to reliably detect known covert timing channels by using a combination of entropy and conditional entropy to detect anomalies in …

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Simulations Of High-Latitude Ionosphere-Magnetosphere Region Plasma Density Structures And The AlfvéN Waves Effects, Fajer Bitar Jaafari Jan 2009

Simulations Of High-Latitude Ionosphere-Magnetosphere Region Plasma Density Structures And The AlfvéN Waves Effects, Fajer Bitar Jaafari

Physics Dissertations

O+ density structures in the polar cap ionosphere-magnetosphere region near 6000 km altitude have been observed with numerous spacecraft, with O+ densities ranging from above 10 cm-3 to lower than 0.01 cm-3. Regions with densities in the low range have been referred to as O+ density troughs [Zeng et al., 2004], or ion depletion zones [Horita et al., 1993]. Regions with high O+ densities are likely caused by processes such as soft auroral electron precipitation and transverse wave heating. In this simulation work, we use the UT Arlington Dynamic Fluid-Kinetic (DyFK) ionospheric plasma transport model to model O+ density profiles …

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Propagation And Generation Of Waves In Solar Atmosphere, Swati Routh Jan 2009

Propagation And Generation Of Waves In Solar Atmosphere, Swati Routh

Physics Dissertations

The fact that the temperature increases with height in the solar atmosphere has been known for many years. To maintain this temperature increase, sources of heating must be present in the atmosphere. One of the most important, and still unsolved, problems in solar physics is to identify the basic physical processes that are responsible for this heating, and explain solar activities caused by the heating. It is also observationally well-established that the solar atmosphere shows a broad range of oscillations that are different in magnetic and non-magnetic regions of the atmosphere.The oscillations are driven by propagating waves, which cause the …

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Design And Analysis Of Effective Routing And Channel Scheduling For Wavelength Division Multiplexing Optical Networks, Xingbo Gao Jan 2009

Design And Analysis Of Effective Routing And Channel Scheduling For Wavelength Division Multiplexing Optical Networks, Xingbo Gao

Electronic Theses and Dissertations

Optical networking, employing wavelength division multiplexing (WDM), is seen as the technology of the future for the Internet. This dissertation investigates several important problems affecting optical circuit switching (OCS) and optical burst switching (OBS) networks. Novel algorithms and new approaches to improve the performance of these networks through effective routing and channel scheduling are presented. Extensive simulations and analytical modeling have both been used to evaluate the effectiveness of the proposed algorithms in achieving lower blocking probability, better fairness as well as faster switching. The simulation tests were performed over a variety of optical network topologies including the ring and …

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Learning Techniques For Information Retrieval And Mining In High-Dimensional Databases, Hao Cheng Jan 2009

Learning Techniques For Information Retrieval And Mining In High-Dimensional Databases, Hao Cheng

Electronic Theses and Dissertations

The main focus of my research is to design effective learning techniques for information retrieval and mining in high-dimensional databases. There are two main aspects in the retrieval and mining research: accuracy and efficiency. The accuracy problem is how to return results which can better match the ground truth, and the efficiency problem is how to evaluate users' requests and execute learning algorithms as fast as possible. However, these problems are non-trivial because of the complexity of the high-level semantic concepts, the heterogeneous natures of the feature space, the high dimensionality of data representations and the size of the databases. …

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Geometric Invariance In The Analysis Of Human Motion In Video Data, Yuping Shen Jan 2009

Geometric Invariance In The Analysis Of Human Motion In Video Data, Yuping Shen

Electronic Theses and Dissertations

Human motion analysis is one of the major problems in computer vision research. It deals with the study of the motion of human body in video data from different aspects, ranging from the tracking of body parts and reconstruction of 3D human body configuration, to higher level of interpretation of human action and activities in image sequences. When human motion is observed through video camera, it is perspectively distorted and may appear totally different from different viewpoints. Therefore it is highly challenging to establish correct relationships between human motions across video sequences with different camera settings. In this work, we …

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Water And The Mountains: Maya Water Mangement At Caracol, Belize, James Crandall Jan 2009

Water And The Mountains: Maya Water Mangement At Caracol, Belize, James Crandall

Electronic Theses and Dissertations

Water management techniques in the Southern Maya Lowlands are both regionally diverse and site specific. This thesis examines the water management strategies of the Classic Period Maya at the site of Caracol, Belize. While it is likely that elites at Caracol controlled the redistribution of resources, i.e. craft and agricultural products, it is probable that the production of agricultural resources and the maintenance of water resource acquisition took place on a more local level. In order to test this hypothesis, a sample of five reservoirs were examined through original research -- and situated in conjunction with past settlement studies -- …

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New Computational Approaches For Multiple Rna Alignment And Rna Search, Daniel Deblasio Jan 2009

New Computational Approaches For Multiple Rna Alignment And Rna Search, Daniel Deblasio

Electronic Theses and Dissertations

In this thesis we explore the the theory and history behind RNA alignment. Normal sequence alignments as studied by computer scientists can be completed in O(n2) time in the naive case. The process involves taking two input sequences and finding the list of edits that can transform one sequence into the other. This process is applied to biology in many forms, such as the creation of multiple alignments and the search of genomic sequences. When you take into account the RNA sequence structure the problem becomes even harder. Multiple RNA structure alignment is particularly challenging because covarying mutations make sequence …

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A Generic Framework For Arabic To English Machine Translation Of Simplex Sentences Using The Role And Reference Grammar Linguistic Model, Yasser Salem Jan 2009

A Generic Framework For Arabic To English Machine Translation Of Simplex Sentences Using The Role And Reference Grammar Linguistic Model, Yasser Salem

Other Resources

No abstract provided.

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Sea Level Rise In Miami-Dade County Florida Implications For Management Of Coastal Wetlands And The Everglades [Presentation], Peter Harlem, John F. Meeder Jan 2009

Sea Level Rise In Miami-Dade County Florida Implications For Management Of Coastal Wetlands And The Everglades [Presentation], Peter Harlem, John F. Meeder

Sea Level Rise Collection

No abstract provided.

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Visual Inspection Of Railroad Tracks, Pavel Babenko Jan 2009

Visual Inspection Of Railroad Tracks, Pavel Babenko

Electronic Theses and Dissertations

In this dissertation, we have developed computer vision methods for measurement of rail gauge, and reliable identification and localization of structural defects in railroad tracks. The rail gauge is the distance between the innermost sides of the two parallel steel rails. We have developed two methods for evaluation of rail gauge. These methods were designed for different hardware setups: the first method works with two pairs of unaligned video cameras while the second method works with depth maps generated by paired laser range scanners. We have also developed a method for detection of rail defects such as damaged or missed …

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Chemical Bath Deposition Of Group Ii-Vi Semiconductor Thin Films For Solar Cells Applications, Hani Khallaf Jan 2009

Chemical Bath Deposition Of Group Ii-Vi Semiconductor Thin Films For Solar Cells Applications, Hani Khallaf

Electronic Theses and Dissertations

Chemical bath deposition (CBD) is the analog in liquid phase of the well-known chemical vapor deposition technique in the vapor phase. In CBD, deposition of thin films takes place from aqueous solutions at low temperatures by a chemical reaction between dissolved precursors, with the help of a complexing agent. Among all techniques used to grow Group II-VI semiconductors, CBD has the advantage of being a simple, low temperature, and inexpensive large-area deposition technique. So far, its contribution in thin film solar cells industry has been mainly limited to growing n-type CdS and/or ZnS window layers for CdTe-based and CIGS-based solar …

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The Role Of Stochastic Resonance And Physical Constraints In The Evolution Of Foraging Strategy, Nathan Daniel Dees Jan 2009

The Role Of Stochastic Resonance And Physical Constraints In The Evolution Of Foraging Strategy, Nathan Daniel Dees

Doctoral Dissertations

"This work represents a detailed study of the optimization of this process: foraging within a single, finite food patch for a limited amount of time. The work is an example of the computational algorithms of statistical physics being applied to the ecological field of foraging behavior. The analysis begins with an examination of the probability distributions observed in the movement parameters of the zooplankton, Daphnia. While foraging, these small aquatic organisms stochastically choose movement parameters with particular levels of variation, or noise, which are similar across several species. Here, related simulations consistently show that these noise levels may be adjusted …

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F₂-Isoprostanes Study After Exposure To Selected Nanoparticles By Liquid Chromatography/Tandem Mass Spectrometry And Investigation Of Nanoparticles On The Cytotoxicity Effect Of Arsenic In Vitro, Xiaoqian Liu Jan 2009

F₂-Isoprostanes Study After Exposure To Selected Nanoparticles By Liquid Chromatography/Tandem Mass Spectrometry And Investigation Of Nanoparticles On The Cytotoxicity Effect Of Arsenic In Vitro, Xiaoqian Liu

Doctoral Dissertations

"Nanopartices as a new class of materials found their applications in industry, aerospace, clinical diagnosis and cancer therapy. Recently, the health effects of nanoparticles have caused people great concerns. This dissertation studies the mechanisms of nanoparticle cytotoxicity in human lung epithelial cells (A549). F₂-isoprostanes are novel reliable biomarkers for lipid peroxidation. In the first part of this work, total free F₂-isoprostanes were quantified by high performance liquid chromatography/mass spectrometry followed by the exposure of SiO₂ (15 nm), CeO₂ (20 nm), Fe₂O₃ (30 nm), and ZnO (70 nm) nanoparticles for 24 hours. For the first time, the results showed that F₂-isoprostanes …

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Design, Synthesis, And Characterization Of Novel Hydrophilic Fluorene-Based Derivatives For Bioimaging Applications, Dao Nguyen Jan 2009

Design, Synthesis, And Characterization Of Novel Hydrophilic Fluorene-Based Derivatives For Bioimaging Applications, Dao Nguyen

Electronic Theses and Dissertations

In this work, hydrophilic fluorene-based derivatives that contain ethylene oxide substituents, have been synthesized and characterized for potential use as new fluorophores for bioimaging applications and for fluorescence sensing of heavy metals. Symmetrical and unsymmetrical fluorene derivatives based on structural types of acceptor-pi-acceptor, acceptor-pi-donor, and donor-pi-donor were characterized by TGA, UV-vis absorption, fluorescence emission, lifetime, anisotropy, and two-photon absorption (2PA) cross section. They were found to possess high thermal stability, high photostability, high fluorescence quantum yields, and generally large two-photon absorption cross sections, making them quite suitable for new probes in single-photon absorption and two-photon absorption fluorescence microscopy imaging. Novel …

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Application Of Alkylsilane Self-Assembled Monolayers For Cell Patterning And Development Of Biolocial Microelectromechanical Systems, Kerry Wilson Jan 2009

Application Of Alkylsilane Self-Assembled Monolayers For Cell Patterning And Development Of Biolocial Microelectromechanical Systems, Kerry Wilson

Electronic Theses and Dissertations

Advances in microfabrication and surface chemistry techniques have provided a new paradigm for the creation of in vitro systems for studying problems in biology and medicine in ways that were previously not practical. The ability to create devices with micro- to nano-scale dimensions provides the opportunity to non-invasively interrogate and monitor biological cells and tissue in large arrays and in a high-throughput manner. These systems hold the potential to, in time, revolutionize the way problems in biology and medicine are studied in the form of point-of-care devices, lab-on-chip devices, and biological microelectromechanical systems (BioMEMS). With new in vitro models, it …

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Synthesis Of Novel Fluorene-Based Two-Photon Absorbing Molecules And Their Applications In Optical Data Storage, Microfabricatio, Ciceron Yanez Jan 2009

Synthesis Of Novel Fluorene-Based Two-Photon Absorbing Molecules And Their Applications In Optical Data Storage, Microfabricatio, Ciceron Yanez

Electronic Theses and Dissertations

Two-photon absorption (2PA) has been used for a number of scientific and technological applications, exploiting the fact that the 2PA probability is directly proportional to the square of the incident light intensity (while one-photon absorption bears a linear relation to the incident light intensity). This intrinsic property of 2PA leads to 3D spatial localization, important in fields such as optical data storage, fluorescence microscopy, and 3D microfabrication. The spatial confinement that 2PA enables has been used to induce photochemical and photophysical events in increasingly smaller volumes and allowed nonlinear, 2PA-based, technologies to reach sub-diffraction limit resolutions. The primary focus of …

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Wilson Inlet Catchment Appraisal 2007, Ron Master Jan 2009

Wilson Inlet Catchment Appraisal 2007, Ron Master

Resource management technical reports

No abstract provided.

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The Initial Hydrological Effect Of Deep Drains At Wallatin Creek : (2006-2008), Richard J. George Dr, Grant Stainer Jan 2009

The Initial Hydrological Effect Of Deep Drains At Wallatin Creek : (2006-2008), Richard J. George Dr, Grant Stainer

Resource management technical reports

No abstract provided.

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