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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Attribution principles for data integration : technology and policy perspectives / Principles of attribution for data integration : technology and policy perspectives

Lee, Thomas Y. (Thomas Yupoo) January 2002 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2002. / Includes bibliographical references (p. [229]-250). / This thesis addresses problems of attribution that arise from the data integration that is exemplified by data re-use and re-distribution on the Web. We present two different perspectives. We begin with a simple definition of attribution, asking what data are we interested in and where does it come from? A formal model and its properties are defined, implementation in an extended relational algebra is described, and application to semistructured data on the Web is discussed. However, because the problem is more than simply what and where, we then expand the scope of our analysis. From the perspective of intellectual property policies, we adopt a broader view of the attribution problem space. A policy analysis that surveys the status quo policy landscape and stakeholder interests is followed by specific policy recommendations. Informed by our technology perspective, we offer two new arguments to support misappropriation as a policy approach to the attribution problem space. Our formal model of attribution is developed in the established foundation of the Domain Relational Calculus (DRC). Three distinct types of attribution are identified: comprehensive, source, and relevant. For each type, we consider the attribution of equivalent DRC expressions, attribution for composed queries, and granularity. An algebra is presented to implement the model. The extended algebra is closed, reduces to the standard relational algebra, and is a consistent extension of the standard algebra. / (cont.) The policy perspective encompasses not only what and where but also integration architectures and the relationships between data providers and users. Information technologies separate the processes and products of data gathering from data selection and presentation. Where the latter is addressed by copyright, the former is not addressed at all. Based upon two traditional, legal-economic frameworks, the asymmetric Prisoner's Dilemma and Entitlement Theory, we argue for a policy of misappropriation to support integration and attribution for data. / by Thomas Y. Lee. / Ph.D.

Product development process design : improving development response to market, technical, and regulatory risks

Unger, Darian W. (Darian William), 1973- January 2003 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2003. / Includes bibliographical references (leaves 181-191). / Engineering companies frequently face product development challenges. Competitive pressures, industrial or societal innovations, and government regulations are some of the many factors that drive the need for new or better products. Companies respond to these drivers and changing needs by developing new products and employing product development processes (PDPs) to coherently manage the risks inherent in their development. Well-designed PDPs reduce development time, create better products, generate profit, and increase market share. In contrast, poorly-designed PDPs can severely harm both product lines and the companies that manufacture them. Many companies seek guidance in making important PDP design decisions. This thesis introduces PDPs as risk management frameworks. The research investigates the relationship between PDPs and risk management and seeks to help companies improve PDP design. It begins by discussing the drivers and risks of product development and then describes different PDPs. The traditional stage gate process is compared with the modified waterfall process, evolutionary prototyping, evolutionary delivery, design to schedule/budget process, the spiral process, and several other PDP variations. The research then proposes several iteration- and review-based metrics by which PDPs can be more effectively identified and compared. Ten company case studies exemplify a wide variety of actual PDPs, demonstrate the utility of iteration and review metrics in distinguishing PDPs, and illustrate how different processes manage different risks. Case study findings indicate that software development companies face rapidly-changing markets, generally perform quick integrations and tests, and are likely to employ flexible PDPs. / (cont.) In contrast, manufacturing companies that face greater integration difficulties and technical risks are likely to employ more rigid PDPs. Integration and risk are both instrumental in determining the applicability of different PDPs. The research employs case study lessons to propose a method for improved PDP design based on risk and integration. To demonstrate the method, it is applied to one company. The thesis concludes that PDPs vary more than previously documented; that the proposed metrics are useful in distinguishing PDPs, their different integrations, and their different risk management methods; and that companies facing different risks can more thoughtfully tailor their PDP designs to suit their own unique circumstances. / by Darian W. Unger. / Ph.D.

Affecting U.S. education through assessment : new tools to discover student understanding / Affecting United States education through assessment : new tools to discover student understanding

Vendlinski, Terry P. (Terry Paul), 1957- January 2001 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Technology, Management, and Policy Program, 2001. / Includes bibliographical references (p. 173-183). / We may have a serious problem with education in the United States. However, the literature suggests one can arrive at differing conclusions about the efficacy of the American educational system depending on what we measure, how we measure it, when we decide to measure, and why we measure. As will be shown, many testing methods currently in vogue in the United States generate data that can lead policy makers, parents, educators, and even students to arrive at invalid conclusions about schools; teachers, and student ability, especially when evaluating the ability of a student to apply (versus just know) concepts. It was hypothesized that, if applied in a manner aligned with accepted validity standards, modern computer technology could both dramatically improve the accuracy of our inferences, and provide significant new insights into student learning and understanding given present national and California state standards. As a "proof of concept", a quasi-experimental, interrupted time series study was conducted using a computerized learning and assessment tool to observe second semester high school chemistry students solving qualitative chemistry problems. The results presented here suggest that: -- Without intervention, once a student chooses a strategy to solve a problem, the student will continue to use the same type of strategy (in both the near- and long-term), whether or not that strategy has proven effective. These findings imply we now have the opportunity to both diagnose ineffective strategies as they are developing, and tailor interventions to individual student needs. -- Because technology allows us to look both at a student's answer and how s)he arrived at that answer, we conclude that we can accurately infer whether a student really understands the concepts of a particular knowledge domain. Our findings suggest that, if properly employed, technology can offer new, real-time insights into student understanding. The paper concludes by discussing the applicability of this research to other knowledge domains, some avenues of future research, and particular pedagogical interventions which the results suggest might be most promising. / by Terry P. Vendlinski. / Ph.D.

Engineering and policy analysis of strategic and tactical options for future aerospace traffic management

Falker, John M January 2002 (has links)
Thesis (Ph. D. in Aerospace Engineering and Policy Analysis)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2002. / Includes bibliographical references (p. 125-128). / Current space launch/landing events are conducted only within Special Use Airspace (SUA), separate from air traffic. This is a strategic traffic management policy because SUA size and duration are set well in advance. It forces space operations to disrupt aviation, which could become costly with growth in air or space transportation. This was investigated through integrated engineering/policy analysis of strategic and tactical options. Total annual disruption cost was calculated using the number of conflicts per SUA event, the annual SUA events, the average disruption per conflict, and the cost per unit disruption. The conflict count was identified as most important, and an analytical airspace conflict model was developed to predict the number of conflicts associated with restricting an arbitrary region of airspace for a given duration. This approach was used to investigate the sensitivity of disruption cost to SUA radius, SUA active duration, air traffic density, relative velocity, annual SUA events, and conflict resolution distance. The current annual cost is under $1 million, but the expected ranges of all factors comprise a plausible range of $100 to $8 million. This cost was most sensitive to SUA radius: on average, doubling the radius multiplies the cost by 49, while doubling the traffic density simply doubles the cost, and doubling the SUA active duration multiplies the cost by only 1.8. / (cont.) The cost was also two orders of magnitude more sensitive to "control" factors (SUA size and duration) than to "market" factors (air and space traffic levels). Four scenarios investigated changes in multiple factors: 2% or 6% annual growth in space operations, managed by reducing only SUA radius or by reducing active duration and scheduling events to affect less air traffic. The results confirmed that radius alone is more powerful than other factors combined, and suggested that tactical alternatives could control costs over time, even with high aerospace transportation growth. However, a preliminary risk analysis indicated a safety need for large SUA, which also offers security benefits. The final recommendations were continued use of SUA for the short-medium term, with detailed safety analysis required for future consideration of several tactical options. / by John M. Falker, III. / Ph.D.in Aerospace Engineering and Policy Analysis

Identifying expression fingerprints using linguistic information

Uzuner, Ozlem, 1975- January 2005 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2005. / Includes bibliographical references (leaves 181-192). / This thesis presents a technology to complement taxation-based policy proposals aimed at addressing the digital copyright problem. The approach presented facilitates identification of intellectual property using expression fingerprints. Copyright law protects expression of content. Recognizing literary works for copyright protection requires identification of the expression of their content. The expression fingerprints described in this thesis use a novel set of linguistic features that capture both the content presented in documents and the manner of expression used in conveying this content. These fingerprints consist of both syntactic and semantic elements of language. Examples of the syntactic elements of expression include structures of embedding and embedded verb phrases. The semantic elements of expression consist of high-level, broad semantic categories. Syntactic and semantic elements of expression enable generation of models that correctly identify books and their paraphrases 82% of the time, providing a significant (approximately 18%) improvement over models that use tfidf-weighted keywords. The performance of models built with these features is also better than models created with standard features used in stylometry (e.g., function words), which yield an accuracy of 62%. In the non-digital world, copyright holders collect revenues by controlling distribution of their works. Current approaches to the digital copyright problem attempt to provide copyright holders with the same kind of control over distribution by employing Digital Rights Management (DRM) systems. / (cont.) However, DRM systems also enable copyright holders to control and limit fair use, to inhibit others' speech, and to collect private information about individual users of digital works. Digital tracking technologies enable alternate solutions to the digital copyright problem; some of these solutions can protect creative incentives of copyright holders in the absence of control over distribution of works. Expression fingerprints facilitate digital tracking even when literary works are DRM- and watermark-free, and even when they are paraphrased. As such, they enable metering popularity of works and make practicable solutions that encourage large-scale dissemination and unrestricted use of digital works and that protect the revenues of copyright holders, for example through taxation-based revenue collection and distribution systems, without imposing limits on distribution. / by Özlem Uzuner. / Ph.D.

Formation and Characterization of Electrospun Nonwoven Webs

Mohan, Abhay 06 February 2003 (has links)
It is known that not all polymers can be melted and extruded to form polymer fibers. Electrospinning process involves a direct method to produce fibers in nanometer range by dissolving the polymer in solvent(s) to form the spinning solution. In this work, the spinning solution was prepared by dissolving Poly (ethylene terephthalate) polymer in triflouroacetic acid and methylene chloride. Charging the solution to a very high potential initiated the process to produce electrospun fibers. With increasing voltage, a critical point is reached and a charged jet of the solution is ejected. As this charged jet moves in the air, the solvent evaporates, leaving behind a charged polymer fiber that collects on a targeted source (rotating drum). Equipment to form electrospun fiberwebs on a rotating drum was designed and successfully built. The equipment for this process is relatively simple and small since this process lend itself to the production of fibers/fiberwebs from small quantity of polymer solution. An experiment was designed to investigate the influence of polymer concentration in the spinning solution and the electric field level on fiber and fiberweb response of interest.<br>Electrospun fibers and fiberwebs were characterized for fiber diameter and its distribution, orientation distribution function, and pore size and its distribution. The results showed that an increase in the electric field resulted in a decrease of the average diameter of the electrospun fibers. It has also been observed that there was concentration/electric field interaction effect on fiber diameter. As the electric field increased keeping polymeric concentration constant, the fibers orientation in machine direction increased. It was observed that as the electric field was increased, the average pore diameter decreased. The decrease in average pore size with increase in electric field was explained in terms of fiber diameter as well as fiberweb structural parameters (orientation and basis weight).

Brand Congruity and Purchase Intentions of Runners

Leksrisompong, Chanatip 29 April 2010 (has links)
Running continues to be one of the more popular sports enjoyed by all ages. Regardless of the popularity of the sport, limited research currently exists to quantify the apparel purchase behavior of runners. This research studied variables that influenced purchase intentions of runners at different levels of involvement. The runners were categorized by the dualistic theory of passion, and their purchase intentions toward apparel brands for running were investigated from the self-congruity perspective. Runners completed an online survey that provided comprehensive information on their running behavior and their past and future apparel purchases. Exploratory factor analysis was used to investigate the dualistic theory of passion and self-congruity theory on the running population. Four variables were found to be important predictors of purchase intentions for all runners: Self-Image Congruence, Function, Aesthetic, and Technology Appeal. Further, logistic regression was used to determine which variables significantly influenced purchase intentions of runners in each category. Based on the findings, a theoretical framework was proposed. This study concluded that functional attributes of running apparel influence runnersâ purchase intentions.

Modeling the Establishment of an Electronic Journal in Textiles & Apparel

Jagannathan, Balachandar 07 June 2002 (has links)
This study identifies how an electronic journal can be established and implemented in the textile and apparel field. The study considers, <a href="http://www.tx.ncsu.edu/jtatm"> Journal of Textile & Apparel Technology & Management </a>as an innovation in the textile and apparel field, and analyzes electronic media as a way of disseminating information to scholarly and industrial communities in a better way. This study documented the process of establishing the electronic journal, and also provides the importance of a feedback loop to provide inputs for future journals. The readership behavior of the journal, including unique visits, repetitive visits, hits (page impressions), geographic location of the readers/visitors, entry page, was examined with the help of log files collected from College of Textiles and Sitestats, a UK based company. Issue analysis (volume 1, issues 1-4, volume 2, issue 1) was compared with previous issues and the results were related to Rogers? Model of the Innovation-Decision process (1995) and proved that JTATM is an innovation in the textile and apparel field.

Weave-Room Performance Decision-Making Process in Textiles: Mapping An Information Engineering Methodology

Karpe, Yatin Surendra 07 September 2006 (has links)
The purpose of this research is to understand, define and map the weave-room performance decision-making process, and to develop an Information Engineering methodology for studying and analyzing decision-making processes in textile manufacturing departments. A preliminary Decision Cycle Model was developed using knowledge management principles, resulting in a definition of Information Engineering, which was ?a technique for extracting the meaning contained in the information so as to allow the understanding needed by the user to make an informed decision?. A case study approach, in conjunction with a process-modeling tool called IDEF0, belonging to the IDEF (Integrated Definition language) family of modeling techniques, has been used. Case studies were conducted at three weaving plants, resulting in the development of the three AS-IS models. These case studies provided the framework to compare with, and become the underlying basis for, the proposed Best Practices TO-BE model of the weave-room performance decision-making process. Additionally, both the AS-IS and TO-BE models lead to the development of ten key performance-improving tasks that could potentially assist in enhancing the decision process as well as providing the background for analyzing the usability of IDEF0 as an effective process-mapping tool, by means of a SWOT analysis. Finally, a generic Information Engineering methodology was developed that could be used for mapping manufacturing-related decisions. The research deliverables resulting from the Information Engineering methodology would eventually lead to the development and creation of a kind of Digital Decision Dashboard (D3), which could potentially prove to be a valuable tool for decision-making in textiles, thus addressing a critical need presently facing the textile industry.

Industry Technology Roadmap for the Flushable Pre-moistened Nonwoven Wipes Industry

Kim, Mun Jung 13 November 2009 (has links)
The body of this research seeks to create an Industry Technology Roadmap for one segment of the U.S. textile and apparel industry, specifically, the flushable pre-moistened wipes industry. Industry Technology Roadmapping is a new type of strategic planning method. Previous technology forecasting methods allowed planners to identify several alternate future states or scenarios and provided uncertainty in either product needs or technological developments. In contrast, Industry Technology Roadmapping allows a company or an industry to proactively plan and prepare for its future by offering future goals, critical requirements and, finally, solutions to achieve the future goals. In addition, Roadmapping works as an effective organizational learning and knowledge creation tool and induces collaboration and new partnerships among companies as well. Currently, flushable pre-moistened nonwoven wipes emerge as new textile products and attempt to expand their future markets. During this research, industry expert interviews and surveys, consumer surveys, heavy user surveys, creation of an Internet blog, and literature review including a patent analysis were conducted for data gathering. The resulting Roadmap provides the nonwoven wipes industry valuable information about the potential future markets, required properties, the current environment of flushable wipes, including challenges, strength, and opportunities, and the solutions. These can help the U.S. nonwoven wipes industry to do informed investment into research, development and manufacturing facilities.

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