Tesi: "Information storage"

1

Scoffin, Robert A. "New materials for optical information storage". Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365756.

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2

Nguyen, Hieu Duy. "It and Bit| Decoherence and Information Storage". Thesis, University of California, Santa Barbara, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3612010.

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We studied two topics: i) how much physical resources are needed to store information and ii) decoherent histories theory applied to Grover search. Given a system consisting of d degrees of freedom each of mass m to store an amount S of information, we find that its average energy, ⟨H⟩, or size, ⟨r²⟩, can be made arbitrarily small individually, but its product ⟨P⟩ = ⟨H⟩⟨ r²⟩ is bounded below by (exp{S/d} − 1)²d²/m. This result is obtained in a nonrelativistic, quantum mechanical setting, and it is independent of earlier thermodynamical results such as the Bekenstein bound on the entropy of black holes.

The second topic is decoherent histories applied to the Grover search problem. The theory of decoherent histories is an attempt to derive classical physics from positing only quantum laws at the fundamental level without notions of a classical apparatus or collapse of the wave-function. Searching for a marked target in a list of N items requires Ω( N) oracle queries when using a classical computer, while a quantum computer can accomplish the same task in O([special characters omitted]) queries using Grover's quantum algorithm. We study a closed quantum system executing Grover algorithm in the framework of decoherent histories and find it to be an exactly solvable model, thus yielding an alternate derivation of Grover's famous result. We also subject the Grover-executing computer to a generic external influence without needing to know the specifics of the Hamiltonian insofar as the histories decohere. Depending on the amount of decoherence, which is captured in our model by a single parameter related to the amount of information obtained by the environment, the search time can range from quantum to classical. Thus, we identify a key effect induced by the environment that can adversely affect a quantum computer's performance and demonstrate exactly how classical computing can emerge from quantum laws.

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3

Bejjani, Ghassan J. "Information storage and access in decisionmaking organizations". Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15142.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1985.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaves 92-94.
by Ghassan J. Bejjani.
M.S.

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4

Gao, Qiang 1964. "Noise reduction techniques for holographic information storage". Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282620.

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The effects of wavefront conditioning on the performance of holographic optical data storage systems is investigated. The physical origins of various noise mechanisms which degrade the SNR of the holographic storage are studied for the thin phase (DCG) and the photoreflective crystal (LiNbO₃) recording materials. Dependence of the noise on various system parameters such as focal length, pixel size, number of pixels and material parameters are studied. An algorithm is developed to design pseudorandom phase masks which can improve the signal-to-noise ratio for a given system. The noise reduction by using pseudorandom phase mask and a Galilean configuration are investigated theoretically and experimentally. Significant improvement to the signal-to-noise ratio of holographic storage systems is demonstrated experimentally.

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5

Fohlin, Johan. "Home Storage Manager". Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-17494.

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6

Shadrin, Alexey [Verfasser]. "Positional Information Storage in Sequence Patterns / Alexey Shadrin". Berlin : Freie Universität Berlin, 2014. http://d-nb.info/1060368056/34.

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7

Varshney, Lav R. (Lav Raj). "Optimal information storage : nonsequential sources and neural channels". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37851.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
MIT Institute Archives copy: pages 101-163 bound in reverse order.
Includes bibliographical references (p. 141-163).
Information storage and retrieval systems are communication systems from the present to the future and fall naturally into the framework of information theory. The goal of information storage is to preserve as much signal fidelity under resource constraints as possible. The information storage theorem delineates average fidelity and average resource values that are achievable and those that are not. Moreover, observable properties of optimal information storage systems and the robustness of optimal systems to parameter mismatch may be determined. In this thesis, we study the physical properties of a neural information storage channel and also the fundamental bounds on the storage of sources that have nonsequential semantics. Experimental investigations have revealed that synapses in the mammalian brain possess unexpected properties. Adopting the optimization approach to biology, we cast the brain as an optimal information storage system and propose a theoretical framework that accounts for many of these physical properties. Based on previous experimental and theoretical work, we use volume as a limited resource and utilize the empirical relationship between volume anrid synaptic weight.
(cont.) Our scientific hypotheses are based on maximizing information storage capacity per unit cost. We use properties of the capacity-cost function, e-capacity cost approximations, and measure matching to develop optimization principles. We find that capacity-achieving input distributions not only explain existing experimental measurements but also make non-trivial predictions about the physical structure of the brain. Numerous information storage applications have semantics such that the order of source elements is irrelevant, so the source sequence can be treated as a multiset. We formulate fidelity criteria that consider asymptotically large multisets and give conclusive, but trivialized, results in rate distortion theory. For fidelity criteria that consider fixed-size multisets. we give some conclusive results in high-rate quantization theory, low-rate quantization. and rate distortion theory. We also provide bounds on the rate-distortion function for other nonsequential fidelity criteria problems. System resource consumption can be significantly reduced by recognizing the correct invariance properties and semantics of the information storage task at hand.
by Lav R. Varshney.
S.M.

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8

Adar, Eytan 1975. "Hybrid-search and storage of semi-structured information". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/46274.

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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.
Includes bibliographical references (p. 113-118).
Given today's tangle of digital information, one of the hardest tasks for computer users of information systems is finding anything in the mess. For a number of well documented reasons including the amazing growth in the Internet's popularity and the drop in the cost of storage, the amount of information on the net as well as on a user's local computer, has increased dramatically in recent years. Although this readily available information should be extremely beneficial for computer users, paradoxically it is now much harder to find anything. Many different solutions have been proposed to the general information seeking task of users, but few if any have addressed the needs of individuals or have leveraged the benefit of single-user interaction. The Haystack project is an attempt to answer the needs of the individual user. Once the user's information is represented in Haystack, the types of questions users may ask are highly varied. In this thesis we will propose a means of representing information in a robust framework within Haystack. Once the information is represented we describe a mechanism by which the diverse questions of the individual can be answered. This novel method functions by using a combination of existing information systems. We will call this combined system a hybrid-search system.
by Eytan Adar.
M.Eng.

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9

Johnston, Reece G. "Secure storage via information dispersal across network overlays". Thesis, The University of Alabama in Huntsville, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10157562.

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In this paper, we describe a secure distributed storage model to be used especially with untrusted devices, most notably cloud storage devices. The model does so through a peer-to-peer overlay and storage protocol designed to run on existing networked systems. We utilize a structured overlay that is organized in a layered, hierarchical manner based on the underlying network structure. These layers are used as storage sites for pieces of data near the layer at which that data is needed. This data is generated and distributed via a technique called an information dispersal algorithm (IDA) which utilizes an erasure code such as Cauchy Reed-Solomon (RS). Through the use of this IDA, the data pieces are organized across neighboring layers to maximize locality and prevent a compromise within one layer from compromising the data of that layer. Speci?cally, for a single datum to become compromised, a minimum of two layers would have to become compromised. As a result, security, survivability, and availability of the data is improved compared to other distributed storage systems. We present signi?cant background in this area followed by an analysis of similar distributed storage systems. Then, an overview of our proposed model is given along with an in-depth analysis, including both experimental results and theoretical analysis. The recorded overhead (encoding/decoding times and associated data sizes) shows that such a scheme can be utilized with little increase in overall latency. Making the proposed model an ideal choice for any distributed storage needs.

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10

Shrestha, Tej Bahadur. "Heterocycles for life-sciences applications and information storage". Diss., Kansas State University, 2010. http://hdl.handle.net/2097/13540.

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Doctor of Philosophy
Department of Chemistry
Stefan H. Bossmann
The photochromic spirodihydroindolizine/betaine (DHI/B) system has been reinvestigated applying picosecond, microsecond, stationary absorption measurements, and NMR-kinetics. The first surprise was that the electronic structure of the betaines is quite different than commonly assumed. The photochemical ring-opening of DHIs to betaines is a conrotatory 1,5 electrocyclic reaction, as picosecond absorption spectroscopy confirms. The (disrotatory) thermal ring-closing occurs from the cisoid betaine. The lifetime of the transoid betaine is 60 s at 300 K, whereas the lifetime of the cisoid isomer is of the order of 250 microseconds. According to these results, the electrocyclic back reaction of the betaines to the DHI is NOT rate determining, as previously thought, but the cisoid-transoid-isomerization of the betaine. Although the presence of a second nitrogen atom increases the photostability of the spirodihydroindolizine-pyridazine/betaine-system remarkably, the photochemical reaction mechanism appears to be exactly the same for spirodihydroindolizine-pyridazine/betaine-system. A nondestructive photoswitch or an information recording systems has been explored using styryl-quinolyldihydroindolizines. Both isomers DHI and betaine are fluorescent. When the blue betaine is stabilized in a thin polymethyl methacrylate (PMMA) matrix, it is stable for several hours even in room temperature and very stable at 77K. Although irradiation of visible light = 532 nm allows the photo-induced reaction of the Betaine back to the DHI, a nondestructive read-out can be performed at λ = 645 nm upon excitation with λ = 580 nm. Image recording (write) and read-out, as well as information storage (at 77K) have been demonstrated. Charged and maleimide-functionalized DHI/B systems have beed synthesized for use as photochemical gates of the mycobacterial channel porin MspA. Positively charged and maleimide functionalized DHI groups that were attached to the DHI/B-system permit the binding of the photoswitch to selective positions in the channel proteins due to the presence of a cysteine moiety. An inexpensive new method for the large scale synthesis of coelenterazine is developed. A modified Negishi coupling reaction is used to make pyrazine intermediates from aminopyrazine as an economical starting material. This method permits the use of up to 1g coelenterazine per kg body weight and day, which turns the renilla transfected stem cells into powerful light sources.

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11

Leenders, Bram. "Heterogeneous Storage in HopsFS". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202970.

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In the recent years, the Apache Hadoop distributed file system (HDFS) has become increasingly popular for the storage of large data sets. Both the volume of the data and the variety of applications is unprecedented. The variety of tasks, each with its own access pattern and demands, calls for a file system that supports specialized storages for different tasks. This thesis describes the implementation of heterogeneous storage in HopsFS, a highly-available, highly-scalable version of HDFS. This makes the cluster aware of different storage types (e.g. hard disks and solid state drives) and allows users to specify preferred storage types for their data. By introducing new storage types, we build in support for storage technologies like SSDs and RAID. The latter is especially of interest, since it increases both bandwidth and reliability of the storage on individual nodes while continuing commodity hardware. Since network bandwidth is increasing orders of magnitude faster than disk bandwidth, increasing the disk throughput is of vital importance to avoid local storage becoming a bottleneck. The heterogeneous storage Application Programming Interface (API) described in this thesis offers HDFS administrators more control over their data while being compatible with the HDFS framework. Users can choose whether they want files stored on traditional disks, SSDs or more complex constructions using RAID and erasure coding.

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12

Wang, Xing. "Benchmarking Cloud Storage Systems". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for telematikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-26716.

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With the rise of cloud computing, many cloud storage systems like Dropbox, Google Drive and Mega have been built to provide decentralized and reliable file storage. It is thus of prime importance to know their features, performance, and the best way to make use of them. In this context, we introduce BenchCloud, a tool designed as part of this thesis to conveniently and efficiently benchmark any cloud storage system.First, we provide a study of six commonly-used cloud storage systems to identify different types of their features. Then existing benchmarking tools for cloud systems are presented, and the requirements, design goals and internal architecture of BenchCloud are studied. Finally, we show how to use BenchCloud to analysis cloud storage systems and take a series of experiments on Dropbox to show how BenchCloud can be used to benchmark and inspect various kinds of features of cloud storage systems.

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13

Yuanjia, Gong. "Multi-version Storage: Code Design and Repair in Distributed Storage Systems". Thesis, KTH, Teknisk informationsvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209546.

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With the rapid growth of data volume, data storage has attracted more and more researchinterests in recent years. Distributed storage systems play important roles ofmeeting the demand for data storage in large amounts. That is, data are stored bymultiple storage nodes which are connected together with various network topologies.The main merits of such distributed storage are faster response, higher reliability andbetter scalability. However, due to network failure, link outage or bu↵er overflow, theupdated data might not be received by all storage nodes, resulting in the coexistenceof multiple versions of the file in the system. Thus, the major challenge is consistency,which means that the latest version of the file is accessible to any read request. We aimto study multi-version storage and code design in distributed storage systems, where thelatest version of the file or a version close to the latest version is recoverable. Moreover,compared to previous studies, higher availability can be achieved in our system model,namely, at least one version of the file can be obtained.On the other hand, both storage nodes and links are vulnerable to fail in storage systems.For the sake of reliability demand, the lost data is supposed to be reconstructed.In this thesis, additional storage nodes dedicated to repair (DR storage nodes) are introducedin the repair process. The results show that optimal repair bandwidth withminimal additional storage space can be achieved by introducing a certain number ofDR storage nodes. Subsequently, linear combinations are provided to reduce the communicationcost of repair where the link cost is high. Last but not the least, we showthat the cooperation among surviving nodes and DR storage nodes suffices to completethe repair process successfully even with link failure.
Med tanke på den snabbt växande volymen av data, har intresset för forskning på datalagring vuxit under de senaste åren. Distribuerade lagringssystem spelar en viktig rolli att möta behovet av stora volymer av lagring. Distribuerade lagringssystem är alltsånär data är sparad på flera noder som är sammankopplade på olika sätt i ett nätverk.Jämfört med traditionella lokala lagringar, har distribuerad lagring fördelen att den harkortare svarstider, högre tillförlitlighet och bättre skalbarhet. Men om nätverket gårner, det blir ett länkavbrott eller maxkapaciteten i en buffert nås, kan det hända attall uppdatering inte når ut till alla noder, vilket resulterar i att flera olika versioner aven fil finns sparande samtidigt i systemet. Därför är en av utmaningarna är att varakonsekvent, att det alltid är den senaste versionen av en fil finns tillgänglig för allavid varje given tidpunkt. Målet med detta arbete är att studera flerversionslagrade fileroch hur programmeringsdesignen för distribuerade lagringssystem ser ut. Med andraord, finns det flera versioner av en fil, ska alla kunna återskapas. Jämfört med tidigarestudier, har vi med vårt system uppnått högre tillgänglighet, nämligen att en klient harfått tag i alla fall en version av en fil.Ett vanligt förkommande problem i det distribuerade lagringssystemen är fel i nodernaoch då ska en ny nod skapas för att öka behovet av tillit. I detta projekt, extralagringsnoder för reparation (DR lagringsnoder) är introducerade i reparationsprocessen.Resultatet visar att den optimala reparationsbandbredden med minimalt extra lagringsutrymmekan uppnås genom att introducera en specifikt antal DR lagringsnoder.Efter det, linjärkombinationer är framtagna för att reducera kostnaden att reparera därlänkkostnaden är hög. Sist men inte minst har vi kunnat påvisa att samarbete medandra fortfarande uppkopplade noder och med DR lagringsnoderna räcker för att utföraen lyckad reparationsprocess, även med länkavbrott.

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14

湯旭瑜。 e Yuk-yue Tong. "Information organization and storage: the role of implicit theories". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31221737.

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15

Ware, John Mark. "Multi-scale data storage schemes for spatial information systems". Thesis, University of South Wales, 1994. https://pure.southwales.ac.uk/en/studentthesis/multiscale-data-storage-schemes-for-spatial-information-systems(38746248-a8d7-4527-ab7a-e874140eda07).html.

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This thesis documents a research project that has led to the design and prototype implementation of several data storage schemes suited to the efficient multi-scale representation of integrated spatial data. Spatial information systems will benefit from having data models which allow for data to be viewed and analysed at various levels of detail, while the integration of data from different sources will lead to a more accurate representation of reality. The work has addressed two specific problems. The first concerns the design of an integrated multi-scale data model suited for use within Geographical Information Systems. This has led to the development of two data models, each of which allow for the integration of terrain data and topographic data at multiple levels of detail. The models are based on a combination of adapted versions of three previous data structures, namely, the constrained Delaunay pyramid, the line generalisation tree and the fixed grid. The second specific problem addressed in this thesis has been the development of an integrated multi-scale 3-D geological data model, for use within a Geoscientific Information System. This has resulted in a data storage scheme which enables the integration of terrain data, geological outcrop data and borehole data at various levels of detail. The thesis also presents details of prototype database implementations of each of the new data storage schemes. These implementations have served to demonstrate the feasibility and benefits of an integrated multi-scale approach. The research has also brought to light some areas that will need further research before fully functional systems are produced. The final chapter contains, in addition to conclusions made as a result of the research to date, a summary of some of these areas that require future work.

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16

Komaragiri, Vivek Chakravarthy. "Application of decision diagrams for information storage and retrieval". Master's thesis, Mississippi State : Mississippi State University, 2002. http://library.msstate.edu/etd/show.asp?etd=etd-04082002-144345.

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17

Tong, Yuk-yue. "Information organization and storage : the role of implicit theories /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20715572.

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18

Gregory, Michael W. (Michael Walter). "Interrelational Laboratory Information System for Data Storage and Retrieval". Thesis, University of North Texas, 1989. https://digital.library.unt.edu/ark:/67531/metadc935708/.

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The necessity for a functional user friendly laboratory data management program has become evident as the quantity of information required for modern scientific research has increased to to titanic proportions. The required union of strong computer power, ease of operation, and adaptability have until recently been outside the realm of most research laboratories. Previous systems, in addition to their high cost, are necessarily complex and require software experts in order to effect any changes that the end user might deem necessary. This study examines the Apple Macintosh computer program Hypercard as an interactive laboratory information system that is user-friendly, cost effective, and adaptable to the changing demands within a modern molecular or microbiology.

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19

SENIGAGLIESI, LINDA. "Information-theoretic security techniques for data communications and storage". Doctoral thesis, Università Politecnica delle Marche, 2019. http://hdl.handle.net/11566/263165.

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Negli ultimi anni il bisogno di sicurezza e privacy è cresciuto in maniera esponenziale in molti aspetti delle comunicazioni, parallelamente allo sviluppo tecnologico. La maggior parte dei sistemi di sicurezza attualmente implementati sono basati sulla nozione di sicurezza computazionale, e devono essere continuamente tenuti aggiornati per affrontare il miglioramento degli attacchi e l’avanzamento tecnologico. Allo scopo di soddisfare requisiti sempre più stringenti e rigorosi, di recente è cresciuto l’interesse verso soluzioni appartenenti al paradigma della teoria dell’informazione a supporto di schemi di segretezza prettamente crittografici, in particolare grazie alla capacità di queste soluzioni di garantire sicurezza indipendentemente dalla capacità dell’attaccante, altrimenti nota come sicurezza incondizionata. In questo lavoro di tesi il nostro scopo è quello di analizzare come metriche di segretezza relative alla teoria dell’informazione possono essere applicate in sistemi pratici con lo scopo di garantire la sicurezza e la privacy dei dati. Per iniziare, vengono definite delle metriche di tipo information-teoretiche per valutare le prestazioni di segretezza di sistemi realistici di comunicazione wireless sotto vincoli pratici, e con esse un protocollo che combina tecniche di codifica per sicurezza a livello fisico con soluzioni crittografiche. Questo schema è in grado di raggiungere un dato livello di sicurezza semantica in presenza di un attaccante passivo. Allo stesso tempo vengono presi in considerazione molteplici scenari: viene fornita un’analisi di sicurezza per canali paralleli con nodi relay, trovando l’allocazione ottima di risorse che massimizza il secrecy rate. Successivamente, sfruttando un model checker probabilistico, vengono definiti i parametri per sistemi di storage distribuiti ed eterogenei che permettono di raggiungere la segretezza perfetta in condizioni pratiche. Per garantire la privacy, proponiamo inoltre uno schema che garantisce il recupero privato delle informazioni in uno scenario di caching wireless in presenza di nodi malevoli. Definiamo infine il piazzamento ottimale dei contenuti tale minimizzare l’uso del canale di backhaul, riducendo così il costo delle comunicazioni del sistema.
The last years have seen a growing need of security and privacy in many aspects of communications, together with the technological progress. Most of the implemented security solutions are based on the notion of computational security, and must be kept continuously updated to face new attacks and technology advancements. To meet the more and more strict requirements, solutions based on the information-theoretic paradigm are gaining interest to support pure cryptographic techniques, thanks to their capacity to achieve security independently on the attacker’s computing resources, also known as unconditional security. In this work we investigate how information-theoretic security can be applied to practical systems in order to ensure data security and privacy. We first start defining information-theoretic metrics to assess the secrecy performance of realistic wireless communication settings under practical conditions, together with a protocol that mixes coding techniques for physical layer security and cryptographic solutions. This scheme is able to achieve some level of semantic security at the presence of a passive attacker. At the same time, multiple scenarios are considered. We provide a security analysis for parallel relay channels, thus finding an optimal resource allocation that maximizes the secrecy rate. Successively, by exploiting a probabilistic model checker, we define the parameters for heterogeneous distributed storage systems that permit us to achieve perfect secrecy in practical conditions. For privacy purposes, we propose a scheme which guarantees private information retrieval of files for caching at the wireless edge against multiple spy nodes. We find the optimal content placement that minimizes the backhaul usage, thus reducing the communication cost of the system.

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Kim, Hyojun. "Informed storage management for mobile platforms". Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45768.

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Storage devices are rapidly changing, and we need to adapt the OS storage software stack to keep up with the changes. Such a re-evaluation of the storage software stack is especially required for mobile platforms because they are relying on inexpensive flash storage devices having very different performance characteristics from the familiar hard disk.In this thesis work, we first show the importance of storage in mobile platforms; contrary to conventional wisdom, we find evidence that storage is a significant contributor to application performance on mobile devices. Then, we explore the solution space for flash storage; user-level library for selective logging, host-side write buffering layer, and OS buffer replacement scheme for flash storage have been studied. Finally, we build an integrated solution for smartphone storage, named Fjord. In the Fjord study, we re-design logging and RAM buffering solutions for smartphones, and also propose fine-grained reliability control mechanisms. We prove that non-volatile logging can improve storage performance remarkably. Understanding the characteristics of cloud-backed applications and controlling the reliability constraint for chosen cloud-backed applications can achieve additional significant performance gain.We implement and evaluate our solution on a real Android smartphone, and demonstrate significant performance gains for everyday apps on such platforms.

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21

Cheng, Antonio S. "A robust distrubuted storage system for large information retrieval applications". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0005/MQ40934.pdf.

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22

De, Ridder Ryan (Ryan James). "Business strategy of nucleic acid memory for digital information storage". Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/110132.

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Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 62-67).
Nucleic acid memory (NAM) is the storage of digital data by encoding the information into the medium of nucleic acids. This is often called DNA storage, as typically, but not necessarily, the information is stored in the nucleobases that comprise DNA. Baum first introduced this idea in 1995, but it wasn't until 2012 that Church proved the idea on a larger scale. NAM has a number of features that make it very promising as a data storage medium. The three typically highlighted are capacity density, data retention (i.e., durability), and energy usage. NAM should enter the data storage market, as a hardware product, through the ~$4.5B archiving market, by targeting large storage service providers and large data-intensive corporations with on-premise operations. A NAM product has the potential to reduce the capital and operational cost base of these companies, by millions of dollars per year. An architecture strategy should be employed to enter the market, relying on control over underlying ideas and partnerships to barricade the company from competition. NAM is a decade away from commercialization, making this a very risky early stage venture. The costs need to come down at least 100,000-fold before the technology is cost competitive with current solutions. Additionally, there are a number of scientific and engineering issues that need to be carefully resolved. Due to the risks, the only viable funding source is government grants. If early stage funding were secured, IP should be developed in the core NAM technology of storage and access and an interim revenue source established. This would allow the company a strong chance to thrive in the competitive storage industry, if and when NAM becomes cost competitive.
by Ryan de Ridder.
S.M. in Engineering and Management

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23

Farfan, Fernando R. "Efficient Storage and Domain-Specific Information Discovery on Semistructured Documents". FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/126.

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The increasing amount of available semistructured data demands efficient mechanisms to store, process, and search an enormous corpus of data to encourage its global adoption. Current techniques to store semistructured documents either map them to relational databases, or use a combination of flat files and indexes. These two approaches result in a mismatch between the tree-structure of semistructured data and the access characteristics of the underlying storage devices. Furthermore, the inefficiency of XML parsing methods has slowed down the large-scale adoption of XML into actual system implementations. The recent development of lazy parsing techniques is a major step towards improving this situation, but lazy parsers still have significant drawbacks that undermine the massive adoption of XML. Once the processing (storage and parsing) issues for semistructured data have been addressed, another key challenge to leverage semistructured data is to perform effective information discovery on such data. Previous works have addressed this problem in a generic (i.e. domain independent) way, but this process can be improved if knowledge about the specific domain is taken into consideration. This dissertation had two general goals: The first goal was to devise novel techniques to efficiently store and process semistructured documents. This goal had two specific aims: We proposed a method for storing semistructured documents that maps the physical characteristics of the documents to the geometrical layout of hard drives. We developed a Double-Lazy Parser for semistructured documents which introduces lazy behavior in both the pre-parsing and progressive parsing phases of the standard Document Object Model's parsing mechanism. The second goal was to construct a user-friendly and efficient engine for performing Information Discovery over domain-specific semistructured documents. This goal also had two aims: We presented a framework that exploits the domain-specific knowledge to improve the quality of the information discovery process by incorporating domain ontologies. We also proposed meaningful evaluation metrics to compare the results of search systems over semistructured documents.

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24

Gholipour, Behrad. "Novel chalcogenide optoelectronic and nanophotonic information storage and processing devices". Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/341256/.

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This project is focused on the application of new electronic and optical materials. In particular it involves examining the use of chalcogenide thin films as phase change and ion conducting glasses for emerging optoelectronic applications. The ability of this group of materials to easily change their state from glass to crystal has meant that they have been widely used in CD's and DVDs. However, their ability to also conduct electrons and ions, promises novel solutions for next generation logic and memory devices which will take us in the short term beyond the limits of the silicon chip and, into the world of neuromorphic cognitive computing (computers that think and adapt). Additionally, this reversible change in the structure of these thin films allows their utilisation in ultra-high speed optical and optoelectronic switches to power the internet and future computers. Three main goals are pursued within this research. First, next generation phase change (PCRAM) and nano-ionic resistive (ReRAM) memory is pursued for faster, non-volatile high density data storage. Secondly, the design of novel processing elements like next generation logic gates enabling neuromorphic cognitive processing and data storage in one structure based on material properties. Finally, the integration of phase change thin films with metamaterial arrays to produce electro-optic and all optical switches for future photonic computers and communication networks.

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Bae, Sanghoon. "Development of a real-time and geographical information system-based transit management information system". Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-11242009-020226/.

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26

Kerkinos, Ioannis. "Evaluation and benchmarking of Tachyon as a memory-centric distributed storage system for Apache Hadoop". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189571.

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Hadoop was developed as an open-source software framework that leveraged initially the MapReduce programming model and therefore was able to efficiently analyse and process large datasets. At the core of Hadoop is the Hadoop distributed file system or HDFS, which is used as the default storage across the cluster. Hadoop can also be used with other types of storage, with or without HDFS, such as Amazon S3, Windows Azure Storage Blobs, GlusterFS, Tachyon etc. This thesis focuses on Tachyon, a distributed file system that claims to enable reliable data sharing at memory speed across cluster computing frameworks. We benchmark and evaluate HDFS with and without Tachyon in regards to performance. To do so we used TestDFSIO as a benchmark to simulate different MapReduce workloads and an in-production Spark job from Spotify. Tachyon's different writetypes were also put to the test and evaluated. To see how cloud solutions compare, we perform the same evaluations of Tachyon over Google Cloud Storage.

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27

Watkins, Alfred R. "Continuous media object modeling, storage, and retrieval". Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/9184.

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28

ATCHESON, PAUL DONALD. "AN INVESTIGATION OF ANALOG OPTICAL STORAGE THROUGH PHOTOCHEMICAL HOLE-BURNING". Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/188022.

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We have examined the technique of persistent spectral holeburning as a method for analog optical data storage. Two types of materials were examined from a theoretical standpoint, ones which exhibit photochemical holeburning (PHB) and ones which exhibit nonphotochemical holeburning (NPHB). We have presented the conditions under which a PHB material shows a linear relation between hole depth and exposure intensity or exposure time. Also we show that a NPHB material has no such condition. We conclude that a PHB material may be useful for analog optical data storage, while a NPHB material would not. Experiments were conducted with a NPHB material, R' color centers in LiF, to support the NPHB analysis.

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Xu, Deyan. "A knowledge-based information storage and retrieval system for natural languages". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0031/MQ47379.pdf.

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30

Bromwich, Thomas Joseph. "The development and characterisation of magnetic nanodots for information storage applications". Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426380.

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31

Hasselmo, M. E. "The representation and storage of visual information in the temporal lobe". Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379950.

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32

Tan, Thiam Chu. "The development of an intelligent conceptual information storage and retrieval system". Thesis, University of Sunderland, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358839.

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33

Sharma, Munish. "SHARIF: Solid Pod based Secured Healthcare Information Storage and Exchange Solution". Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-105147.

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Health Informatics has enlightened by the recent development in the internet of medical things 4.0. Healthcare services have seen greater acceptance of Information and Communications Technology (ICT) in recent years; in light of the increasing volume of patient data, the traditional way of storing data in physical files has eventually moved to a digital alternative such as Electronic Health Record (EHR). However, the conventional healthcare data systems are plagued with a single point of failure, security issues, mutable logging, and inefficient methods to retrieve healthcare records. Solid (Social Linked Data) has been developed as a decentralized technology to alter digital data sharing and ownership for its users radically. However, Solid alone cannot address all the security issues posed to data exchange and storage. This work combines two decentralized technologies, Solid ecosystem and Blockchain technology, to tackle potential security issues using Solidity-based Smart Contracts, thereby providing a secure patient centric design. This research evaluates a model solution for secure storage, emphasizing secure auditing of accessing the data stored. The architecture will also come with algorithms that will provide developers with logical instructions to implement the artefact.

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Sloof, Joël. "Classification Storage : A practical solution to file classification for information security". Thesis, Karlstads universitet, Institutionen för matematik och datavetenskap (from 2013), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-84553.

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In the information age we currently live in, data has become the most valuable resource in the world. These data resources are high value targets for cyber criminals and digital warfare. To mitigate these threats, information security, laws and legislation is required. It can be challenging for organisations to have control over their data, to comply with laws and legislation that require data classification. Data classification is often required to determine appropriate security measured for storing sensitive data. The goal of this thesis is to create a system that makes it easy for organisations to handle file classifications, and raise information security awareness among users. In this thesis, the Classification Storage system is designed, implemented and evaluated. The Classification Storage system is a Client--Server solution that together create a virtual filesystem. The virtual filesystem is presented as one network drive, while data is stored separately, based on the classifications that are set by users. Evaluating the Classification Storage system is realised through a usability study. The study shows that users find the Classification Storage system to be intuitive, easy to use and users become more information security aware by using the system.
I dagens informationsålder har data blivit den mest värdefulla tillgången i världen. Datatillgångar har blivit högt prioriterade mål för cyberkriminella och digital krigsföring. För att minska dessa hot, finns det ett behov av informationssäkerhet, lagar och lagstiftning. Det kan vara utmanande för organisationer att ha kontroll över sitt data för att följa lagar som kräver data klassificering för att lagra känsligt data. Målet med avhandlingen är att skapa ett system som gör det lättare för organisationer att hantera filklassificering och som ökar informationssäkerhets medvetande bland användare. Classification Storage systemet har designats, implementerats och evaluerats i avhandlingen. Classification Storage systemet är en Klient--Server lösning som tillsammans skapar ett virtuellt filsystem. Det virtuella filsystemet är presenterad som en nätverksenhet, där data lagras separat, beroende på den klassificeringen användare sätter. Classification Storage systemet är evaluerat genom en användbarhetsstudie. Studien visar att användare tycker att Classification Storage systemet är intuitivt, lätt att använda och användare blir mer informationssäkerhets medveten genom att använda systemet.

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Netshiongolwe, Mpho. "Investigating perceptions of reliability, efficiency and feasibility of data storage technology: A case study of cloud storage adoption at UCT Faculty of Science". Master's thesis, Faculty of Humanities, 2019. http://hdl.handle.net/11427/30935.

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Within an increasing number of organisations cloud storage is becoming more common as large amounts of data from people and projects are being produced, exchanged and stored (Chang & Wills, 2016: 56). In fact, “technology has evolved and has allowed increasingly large and efficient data storage, which in turn has allowed increasingly sophisticated ways to use it (Staff, 2016: n.p.). Thus, the aim of this study is to investigate the perceptions of reliability, efficiency and feasibility of data storage technology. The investigation is done by addressing claims and perceptions of data storage technology within the Faculty of Science at UCT. This study intends to determine if cloud storage is the future of storing, managing and preservation of digital data. The study used a qualitative research method grounded by Management Fashion Theory. Data was collected from three case studies from the Faculty of Science, and also from a desktop internet search on the marketing of cloud storage. Data collection from the case studies was facilitated through semi-structured interviews and from three researchers and academics who are working on cloud storage projects. Main themes that guided the dialogue during data collection originated from reviewed literature. The study concludes that cloud storage is the way forward for storing, sharing and managing research data. Academic researchers find storing data on cloud beneficial; however, it comes with challenges such as costs, security, access, privacy, control and ethics.

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Fei, Qi. "Operation models for information systems /". View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?IELM%202009%20FEI.

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Lee, Jaejin. "Robust multitrack modulation codes for the storage channel". Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/15034.

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38

Chanana, Vivek, University of Western Sydney, of Science Technology and Environment College e School of Computing and Information Technology. "Enhancing information retrieval effectiveness through use of context". THESIS_CSTE_CIT_Chanana_V.xml, 2004. http://handle.uws.edu.au:8081/1959.7/719.

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Information available in digital form has grown phenomenally in recent years. Finding the required information has become a difficult and challenging task. This is primarily due to the diversity and enormous volume of information available and the change in the nature of people now seeking information – from experts to ordinary users of desktop computers with varying interest and objectives. The problem of finding relevant information is further impacted by the poor retrieval effectiveness of most current information retrieval (IR) systems that are primarily based on keyword indexing techniques. Though these systems retrieve documents that contain those keywords specified in the query, the documents that are retrieved may not necessarily be in the context in which the user would have wanted them to be. This research works argues that exploiting the user’s context of the information need has the potential to improve the performance of information retrieval systems. Context can reduce the ambiguity by associating meanings to request/query terms, and thus limit the scope of the possible misinterpretations of query terms. A new way of defining context categories based on information type is proposed and this notion of context differs from the conventional way of defining information categories based on subject topics as it is closely linked with the situation in which the user’s needs for information originates. A new context-based information retrieval system where users could specify the context in which they are seeking information is presented. This work also includes a full-scale development, implementation and evaluation of the new context-based information system
Doctor of Philosophy (PhD)

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Wang, Jiying. "Information extraction and integration for Web databases /". View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?COMP%202004%20WANGJ.

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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2004.
Includes bibliographical references (leaves 112-118). Also available in electronic version. Access restricted to campus users.

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40

Chen, QiFan. "An object-oriented database system for efficient information retrieval applications". Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06062008-170433/.

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41

Ho, Lai-ming. "Evaluation of the development and impact of clinical information systems /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19657857.

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42

Lin, Chang-Mei. "CICC Information System /". Online version of thesis, 1992. http://hdl.handle.net/1850/11094.

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43

Coles, Susan. "Personal information systems : the implications of job and individual differences for design". Thesis, Loughborough University, 1990. https://dspace.lboro.ac.uk/2134/33024.

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In an age where information has become a crucial commodity, accessing appropriate information quickly is essential to economic success. Developing ways of improving information retrieval is therefore of central concern to human factors and technologists alike. One aspect of information access relates to the ability of individual office workers to manage and retrieve their own information effectively, and this is what the present research addresses. Previous work in the area has been dominated by designing computer interfaces for the average user. This research investigates how people's needs might differ according to circumstance and examines a wider range of design possibilities. Specifically it sets out to relate retrieval problems (specific information retrieval rather than e.g. browsing or reminding) to job and individual (personality) differences within the general context of personal information management in offices using traditional technologies of paper, filing cabinets and desks. This is achieved by both extensive fieldwork and the use of simulated filing-retrieval systems in a controlled context.

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44

Tedori, Veronica. "Design of a safety management information and tracking system". Master's thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-03302010-020341/.

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45

Jennings, Daniel Blair. "Welding information system : design, operations, methods". Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29988.

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This thesis encompasses a Welding Information System for Design, Operations, and Methods (WISDOM). In essence, the WISDOM project aimed at research and development of an innovative and comprehensive information collection on welding in close cooperation with industry utilizing modern micro-computer techniques of information review, retrieval, storage, updating, and transfer. Emphasis is placed on new and more efficient methods of knowledge communication, pursuing the idea of exploring knowledge (in contrast to rehearsing recipes). The development of this project concentrated on the following three main topics: 1. Background information on steel metallurgy and welding 2. Analysis and Design Methods for Welded Connections 3. Code Requirements of Welds Preliminary research on the WISDOM project involved communications with industry to determine primary objectives. The need for an information system on welding was unquestionably apparent. The knowledge base is supplemented with graphic images and analysis and design programs. It is hoped that the information in this system will be delivered to the engineer in an efficient and useful manner. The priority here is to raise welding awareness while promoting efficient welded design. In addition, we hope that the WISDOM system will close the ever widening gap between the design engineer and the fabricator. In the most general sense, the primary objective of the WISDOM project was to produce an integrated self-paced teaching tool for both engineering professional and student alike. The versatility of the system is maintained by presenting the information in modular form. Screen graphics oriented learning modules encourage the user to become more involved in the learning process than more conventional teaching methods allow. Analysis and design modules promote rapid and efficient connection design in a more consistent and professional manner. A smooth transition from the learning environment to engineering practice is envisioned by providing realistic design tools with a transparent background.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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Rogers, Camille Françoise. "Teaching ethics in the Information Systems curriculum". Click here to access dissertation, 2006. http://www.georgiasouthern.edu/etd/archive/spring2006/cfrogers/Rogers%5FCamille%5FF%5F200601.pdf.

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Thesis (Ed.D.)--Georgia Southern University, 2006.
"A dissertation submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Doctor of Education." ETD. Includes bibliographical references (p. 144-157).

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47

Mukherjea, Sougata. "Visualizing the information space of hypermedia systems". Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/8223.

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48

Yeung, Chung Kei. "Ontological model for information systems development methodology". HKBU Institutional Repository, 2006. http://repository.hkbu.edu.hk/etd_ra/702.

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49

Fraser, Mark E. "Architecture and methodology for storage, retrieval and presentation of geo-spatial information". [Gainesville, Fla.] : University of Florida, 2001. http://purl.fcla.edu/fcla/etd/UFE0000316.

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Thesis (M.S.)--University of Florida, 2001.
Title from title page of source document. Document formatted into pages; contains xi, 77 p.; also contains graphics. Includes vita. Includes bibliographical references.

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50

Lomerson, William L. (William Lough). "Information Technology Needs of Professional Education Faculty with the Implications for the Design of Information Technology Systems". Thesis, University of North Texas, 1992. https://digital.library.unt.edu/ark:/67531/metadc332783/.

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This study identified determinants existing within the academic environment of professional education faculty that influence the development and implementation of an information technology system to support their professional endeavors. Such a system would encourage these faculty to integrate technology into their curriculum and, consequently, produce teacher graduates who could employ information technology effectively in teaching. This study used a field survey research design with a mailed questionnaire. Both institutional and personal demographic factors were examined. The population exhibited a high level of homogeneity. This study indicated that ease of use, reliable operation, and capability to integrate technology into their personal work style were the most important concerns of faculty members. These factors reduce the emotional and intellectual costs of using technology.

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Tesi sul tema "Information storage"

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