Sentralt i hovedfagsoppgaven står det klassiske problemet; der innføring av ny teknologi krever utvikling av nye metoder og arbeidsrutiner, samtidig som de gamle rutinene får bestå tilnærmet uendret. Dette gjør at kompleksiteten i organisasjonenes systemer øker, da både gamle og nye metoder samt arbeidsrutiner må vedlikeholdes. Dette har skjedd hos Adresseavisen. Ved innføring av ny teknologi, og nye arbeidsmetoder, har man ikke hatt en helhetlig tenkning på arbeidsflyten og organisasjonsstrukturen. Dette ser man ved valg av løsning på analoge vs. digitale bilder, og på papiravis vs. nettutgaven av avisen.Konkret tar denne hovedoppgaven for seg gjenfinningen av dokumenter i dagsaviser, der hvordan NewsML-formatet kan brukes til dette formålet står sentralt. NewsML ble lansert av International Press and Telecommunications Council (IPTC), i samarbeid med nyhetsbyråene Reuters og AFP, i 2000. Målet med NewsML er å få et helhetlig format som dekker alle ledd i nyhetsobjektets livssyklus, der samme artikkel kan lagres med ulikt språk og med støtte for alle formater og visningsmedier.Informasjonsgjenfinning er viktig både for journalistene som skal lage en god avis, og for leserne som ønsker å søke etter artikler, for eksempel på internett. Gode søkesystemer kan være avgjørende om en avis skal greie å holde på en leser. I hovedoppgaven er søkeprosessen i seg selv beskrevet, i tillegg til ulike kriterier som et søkesystem kan vurderes etter. Som eksempel på hvordan systemet er i en dagsavis, beskrives Adresseavisens sitt system for lagring og gjenfinning av data. Adresseavisen skiller klart mellom ulike nyhetsobjekt som for eksempel tekst, lyd, bilder eller film. Disse ulike nyhetsobjektene til papiravisen lagres i ulike databaser, mens nyhetsobjekter til internettavisen lagres i en annen database. Disse ulike nyhetsobjektene beskrives med ulikt metadataformat. Dette gjør at når man ønsker å finne igjen alle delene av en nyhetsartikkel i Adresseavisen må man søke i ulike databaser som har ulike metadataformat. Formatet Adresseavisen bruker gjør at søkeprosessen kan bli noe tungvint. Med mindre personen som utfører søket har god kjennskap til oppbyggingen av databasene og metadataformata, risikerer man å gå glipp av verdifull informasjon.Det er laget mange ulike standarder og formater som skal støtte både gjenfinning, utveksling og lagring av nyheter. Noen av de mest brukte blir kort beskrevet, før NewsML beskrives i detalj. NewsML gir en elegant løsning på problemet Adresseavisen har, med ulike databasser og ulike metadataformater, ved å definere alle nyhetsobjektene som et element uansett hva slags medietype det er av og hva det skal brukes til. Et NewsML-dokument inneholder en kompleks XML struktur. I denne strukturen blir en hele artikkel representert ved hjelp av et element som innholder metadata som er felles for hele nyhetsartikkelen. Inne i dette elementet kan man ha ulike nyhetskomponenter, som igjen kan innholde nye nyhetskomponenter, eller innholdselementer. De ulike nyhetskomponentene kan for eksempel skille mellom samme artikkel på ulike språk. NewsML-standarden har enkelte obligatoriske metadatafelt, men er likevel åpen nok til at ulike mediekonsern med ulike interesser og fokus kan tilpasse et NewsML-system slik at det passer til deres behov. For å illustrere praktisk hvordan NewsML kan bli brukt i Adresseavisen er det laget konverteringstabeller mellom ulike metadataposter i Adresseavisen, opp i mot et NewsML-dokument. Videre er det implementert en prototyp som benytter NewsML, for å vise fordeler og utfordringer ved bruk av NewsML som format. Prototypen implementerer alle NewsML-elementene. Grensesnittet i prototypen viser utfordringene med den komplekse XML-strukturen som NewsML inneholder. Adresseavisen sitt system har en stadig økende kompleksitet, og bør på sikt endres. Ved en slik endring har Adresseavisen flere valg. Et alternativ er å ta i bruk prinsippet NewsML har med å lagre ulike nyhetselementer som like objekter. Disse objektene kan lagres ved hjelp av relasjonsdatabase, slik Adresseavisen har det i dag. Dette vil gjøre at avisen får et enhetlig og oversiktlig system der alle nyhetsobjekter har felles metadataformat, men systemet mister NewsML sin fordel ved at man kan lagre ulike versjoner av en artikkel med samme metadata. En annen løsning er å innføre NewsML med sin komplekse struktur. Man trenger ikke nødvendigvis implementere alle NewsML-elementene med engang, men forenkle strukturen noe og heller utvide ved behov.

I denne oppgaven skal du implementere et statistisk metode for å forbedre et søkeresultat. Du skal bruke Expetcation-Maximization (EM) metode til formålet. Oppgaven går ut på å finne ut hvor nyttig EM til å resortere et initielt søkeresultat slik at de mest relevante treffene kommer først. Du skal da sammenlikne metoden din med andre metoder som allerede er brukt til samme formål.Rent konkret skal du:Implementere EM i Java.Implementere et søkesystem basert på Open Source søkebibliotek som feks. LuceneIntegrere EM i søkesystemet.Evaluere systemet basert på kvaliteten på søkeresultatene. Her skal du bruke standard testkolleksjon med fasit til evalueringen.Du skal sammenlikne resulatet ditt med eksistrene metode(r)Teste ytelsen til EM-algoritmen avhengig av størrelsen på indexen.

The use of social media has increased considerably the recent years, andusers share a lot of their daily life in social media. Many of the users uploadimages to photo-sharing applications, and categorize their images withtextual tags. Users do not always use the best tags to describe the images,but add tags to get "likes" or use tags as a status update. For this reason,searching on tags are unpredictable, and does not necessary return the resultthe user expected.This thesis studies the impact of expanding queries in image searches withterms from knowledge bases, such as DBpedia. We study the methodsTF-IDF, Mutual Information and Chi-square to nd related candidates forquery expansion. The thesis reports on how we implemented and appliedthese methods in a query expansion setting. Our experiments show thatChi-square is the method that yields the best result with the best averageprecision, and was slightly better than a search without query expansion.TF-IDF gave the second best result with query expansion, and Mutual informationwas the method that gave the worst average precision. Queryexpansion with related terms is an exiting eld, and the information fromthis thesis gives a good indication that this is a eld that should be moreexplored in the future.

Latin American experiences are analyzed in order to identify adverse factors, describing the complexity of the implementation of a Fabrication Laboratory in the region. As a starting point we take the implementation done by groups of academics coming back to their origin countries, and others that after the implementation they were born or adapted to an academic supervision (Fab Lab MIT) or a technical and commercial one (Rhino FabLab). In the whole, the results allow to identify opportunities for the future.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Humanities, Program in Writing and Humanistic Studies, 2012. / Cataloged from PDF version of thesis. / A young boy grows up in a future world buried under snow, a great factory and research lab with his father at the head. As he grows he is torn between the desire to be like his beloved father and the equally strong desire to get out from under his shadow in the eyes of those around him, in a world where there is nowhere else to go. Between chapters of this story, a trio of smaller stories set in the present day tells the tale of how the world reached the state shown in the future. Each is the same basic story of the invention of the titular shield that brought about mankind's collapse, told from the perspective of a different observer: once from the shield's inventor, once from a government agent who helped make it a weapon, and once from a former spy recalling parallels to historical events. In viewing parallel events from each of these smaller pieces the reader is able to see how all of the individual actions are rational despite the wholly catastrophic result, and the works also fill in the blanks in each other's stories of what happened as a whole. / by Brian Iglesias. / S.B.

Thesis (S.M.)--Harvard-MIT Division of Health Sciences and Technology, September 2006. / "August 2006." / Includes bibliographical references (leaves 37-38). / This work is an attempt to explain wide variations in drug licensing deal value by using regression modeling to describe and predict the relationship between oncology drug deal characteristics and their licensing deal values. Although the reasons for large variances in value between deals may not be immediately apparent, it was hypothesized that objective independent variables, such as a molecule's phase, its target market size and the size of the acquiring/licensor company could explain a significant portion of variation in cancer drug values. This model, although not predictive when used independently, could be used to supplement other discounted cash flow and market based techniques to help assess the worth of incipient oncology therapies. Using regression analysis to study drug licensing deals is not novel: a study was published by Loeffler et al in 2002 that attempted to assess the impact of multiple variables on deal value in a wide range of pharmaceutical indications. The independent variables in Loeffler's work could explain less than 50% of differences in deal values. It was expected that refining the model could lead to improved regression R squared coefficient and, potentially, be a useful tool for managers. This current work is based on the 2002 Loeffler paper, but differs significantly by: * Focusing on just oncology licensing deals instead of deals covering many indications, * Incorporating a measure of the assets of the larger licensee company, * Accounting for the licensing experience of the smaller licensor company, * Factoring in inflation and the years the deals were signed; and * Assessing the impact of primary indication market size. The goal of the thesis was to advance the art of estimating the value of drug licensing deals by assessing the impact of the aforementioned factors. / by Paul Allen Hawkins. / S.M.

Thesis (Ph. D.)--Harvard-MIT Division of Health Sciences and Technology, June 2007. / Includes bibliographical references (leaves 94-100). / Synaptic plasticity is the substrate of a vast variety of learning mechanisms. However, the molecular pathways and physiological patterns that regulate it are poorly understood. In the first part of this thesis, we focus on the physiological determinants of pre-synaptic plasticity. We find that a complete blockade of activity succeeds in inducing only a transient enhancement of plasticity. A permanent enhancement of synaptic plasticity is achieved by selectively reducing the NMDA-R mediated Ca2+ flux associated with uncorrelated activity, via adjustment of the voltage-dependent Mg2+ block of NMDA receptors. NR2B-containing NMDARs are up-regulated by this treatment, and this is found to be an important contributor to plasticity enhancement. Thus, the quality, but not the quantity, of activity is the important parameter to manipulate to obtain a permanent enhancement of intrinsic plasticity. In the second part, we study the relationship between activity patterns and postsynaptic NMDA-R regulation by using high-precision iontophoresis. We identified a new homeostatic mechanism of NMDA-R regulation which we have thus termed "NMDA Normalization" to differentiate it from prior uses of "NMDA homeostasis." Through this novel Ca++ dependent mechanism, we show that the neuron, by opposing NMDA-R functional expression counter to activity changes, causes the average charge transfer through NMDA-Rs to remain constant. We elucidate the activity-dependent, temporal, and spatial characteristics of this process. We propose an explanatory hypothesis. The reduction of uncorrelated activity used in the first part reduced the NMDA-R mediated average charge transfer. Through normalization, the cell increased functional NMDA-R expression to normalize NMDA-R mediated average charge transfer. However, when a burst of activity arrives in this new condition, in which an identical burst of glutamate release and depolarization now meets a larger number of very weakly activated NMDA-Rs, it is able to induce a disproportionately larger peak Ca++ flux. This increase in the maximal Ca++ flux, due to the combination of reduction of uncorrelated activity and NMDA-R normalization, is responsible in great part for the enhancement of synaptic plasticity. Our findings propose a clear strategy for the development of compounds to restore, and potentially enhance, synaptic plasticity, and thus with likelihood learning and memory. / Ph.D.

Thesis: Ph. D. in Medical Engineering, Harvard-MIT Program in Health Sciences and Technology, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 217-226). / The objective of this work was to develop materials for continuous low-dose delivery of cisplatin directly into the abdomen, also known as intraperitoneal (IP) chemotherapy. IP chemotherapy can help treat peritoneal metastasis in many advanced gynecologic and gastrointestinal cancers and has shown particular promise in treating advanced ovarian cancer. It is however tremendously underutilized because it requires a lot of resources and the current technology and maximum tolerated dose regimen cause complications and severe toxicity to patients. We previously showed that continuous low-dose IP cisplatin delivery via an implanted diffusion-based reservoir device can be as effective as and less toxic than intermittent maximum tolerated dose IP injections. To translate this work to a clinically relevant implantable system, we developed composite materials that can deliver cisplatin at a continuous low dose that is tunable. The materials were mechanically well suited for placement in the abdomen and were evaluated for in vitro bioactivity, in vivo tolerability and in vivo ability to deliver platinum to key abdominal organs with promising results. Dosing studies with different material dimensions helped identify a dose to pilot treatment of ovarian cancer in human xenograft-bearing mice. The implications of more accessible and affordable IP chemotherapy are especially important in countries with limited resources. Design reviews and a clinician survey in India reveal eagerness for early adoption of new technologies and dosing regimens to treat peritoneal metastasis and show promise for utilization of our implant in the developing world. The work described in this thesis carries implications for the treatment of advanced ovarian cancer and peritoneal metastasis of other tumors affecting millions of patients worldwide and may help with the management of nonmalignant conditions with abdominal involvement. / by Aikaterini Mantzavinou. / Ph. D. in Medical Engineering

Thesis (Ph.D.)--Harvard--Massachusetts Institute of Technology Division of Health Sciences and Technology, 1998. / Includes bibliographical references. / by James L. McGrath. / Ph.D.

Thesis (Ph. D.)--Harvard-MIT Division of Health Sciences and Technology, 2003. / Includes bibliographical references (leaves 126-136). / Hair cells are the exquisitely-sensitive mechanosensory transducers of the inner ear. While the electrophysiology of hair cells has been extensively studied, little is known about the vital background processes that maintain the steady-state intracellular ionic environment. This study explored Na-coupled ion transport processes in isolated goldfish hair cells both in the steady state and in response to perturbations. Intracellular Na⁺ concentration ([Na⁺]i) and pH (pHi) were measured using the fluorescent probes SBFI and BCECF, respectively. The total steady-state Na⁺ entry, determined by measuring the initial rate of increase in [Na⁺]i during inhibition of Na⁺,K⁺-ATPase, was 9 mM/min, a rate higher than in many other epithelial cells involved in rapid ion transport. To uncover the entry pathways for such a high Na⁺ influx, pharmacological agents and manipulations of extracellular composition were used to dissect apart the contributions of various transporters or channels. A combination of Na⁺ entry via transduction channels, the Na⁺/H⁺ exchanger, and the Na⁺/Ca²⁺ exchanger accounted for 3/4 of the total steady-state Na⁺ entry. Consistent with a significant component via the Na⁺/Ca²⁺ exchanger, nifedipine, a blocker of L-type calcium channels, also reduced the Na⁺ entry rate. Since the Na⁺/H⁺ exchanger in goldfish hair cells, in contrast to many other cell types, displayed significant activity in the steady state, interactions between regulation of [Na⁺]i and pHi were examined during recovery from intracellular acid loads. The rate of Na+ entry or acid extrusion via the Na⁺/H⁺ exchanger increased by a factor of 6 during recovery from an acid load. In most cells, [Na⁺]i doubled after the acid load and subsequently recovered, even though the / (cont.) was not exogenously inhibited. These results indicate that intracellular acidification inhibits the Na⁺, K⁺-ATPase, and therefore poses a potential conflict for maintenance of intracellular Na⁺ homeostasis. Although hair cells were traditionally described as passive resistors, this thesis demonstrates that goldfish hair cells have a significant metabolic load, even in the steady state, arising from the activities of specific Na⁺-coupled transporters and channels. Under certain pathophysiological circumstances, such as ischemia or acoustic trauma, increased Na⁺ influx via these pathways may overwhelm the ion-homeostatic capabilities of hair cells. / by Diane Elizabeth Ronan. / Ph.D.