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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.
171

Bridging The Gap Between Telemetry and the PC

Nelson, Wade, Shurtleff, Diana 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1988 / Riviera Hotel, Las Vegas, Nevada / The explosive use and extensive development of software and hardware for the IBM PC and PC Clones over the past few years has positioned the PC as one of many viable alternatives to system designers configuring systems for both data acquisition and data analysis. Hardware abounds for capturing signals to be digitized and analyzed by software developed for the PC. Communication software has improved to where system developers can easily link instrumentation devices together to form integrated test environments for analyzing and displaying data. Telemetry systems, notable those developed for lab calibration and ground station environments, are one of many applications which can profit from the rapid development of data acquisition techniques for the PC. Recently developed for the ADS100A telemetry processor is a data acquisition module which allows the system to be linked into the PC world. The MUX-I/O module was designed to allow the PC access to telemetry data acquired through the ADS 100A, as well as provide a method by which data can be input into the telemetry environment from a host PC or equivalent RS-232 or GPIB interface. Signals captured and digitized by the ADS100A can be passed on to the PC for further processing and/or report generation. Providing interfaces of this form to the PC greatly enhances the functionality and scope of the abilities already provided by the ADS100A as one of the major front-end processors used in telemetry processing today. The MUX-I/O module helps "bridge the gap" between telemetry and the PC in an ever increasing demand for improving the quantity and quality of processing power required by today's telemetry environment. This paper focuses on two distinct topics, how to transfer data to and from the PC and what off-the-shelf software is available to provide communication links and analysis of incoming data. Major areas of discussion will include software protocols, pre vs post processing, static vs dynamic processing environments, and discussion of the major data analysis and acquisition packages available for the PC today, such as DaDisp and Lotus Measure, which aid the system designer in analyzing and displaying telemetry data. Novel applications of the telemetry to PC link will be discussed.
172

Skrivsamarbete i högre utbildning : Tre studenters skribentprofiler i kollaborativa skrivargrupper / Collaborative Writing in Higher Education : Profiles of Three Student Writers in Collaborative Writing Groups

Berends, Gerrit January 2013 (has links)
The overarching aim of this thesis is to probe more deeply into how col­laborative writing can help to socialise students in a writing practice. More specifically, the thesis deals with lab report writing and the relationship of three students with different backgrounds to the educational practices of a university department. The three students differ in language background, previous higher education and vocational experience. The material comprises recordings of student discussions while writing lab reports in a group. The students and their lab report writing in different group con­stellations has been followed longitudi­nally for between two to four semesters. In addition the development of the lab reports over time has been studied, as well as teachers’ comments on them. Student acquisition of the genre is linked to internal textual criteria (textual aspects) and to extratextual criteria in the educational context. In view of the study’s focus on group collaboration a socio-cultural per­spective has been adopted as a frame. A model developed by Storch (2002) based on Vygotsky’s role relationships between expert and novice is used to shed light on how the students resolve problems related to the writing task through group discussions. The results show that the students’ backgrounds play a role in the creation of their profiles in the collaborative writing groups. The student with a second-language background often seeks support, not least where linguistic correctness is concerned, and cites what teachers say as arguments. The student with prior experience of academic writing appears to be a seasoned writer, for instance by daring to deviate from instructions and teachers’ directives. The third student uses his professional experience of writing lab reports in discussions to gain acceptance for his ideas.
173

Authoritarian collaboration : Unexpected effects of open government initiatives in China

Wallin, Pontus January 2014 (has links)
There is a recent emergence of open government initiatives for citizen participation in policy making in China. Open government initiatives seek to increase the level of participation, deliberation and transparency in government affairs, sometimes by use of Internet fora. In contemporary political science the introduction of these initiatives in authoritarian contexts has been described as a paradox of authoritarian deliberation. This thesis uses cybernetic theory, perspectives of information steering in all systems, to resolve the paradox and present a new view on authoritarianism and autocracy. A cybernetic definition of autocracy allows for an analysis of different types of autocracy in different models of governance. The theoretical tools developed are used to define and assess the potential for democratic autocracy, representative autocracy, deliberative autocracy and collaborative autocracy in online open government initiatives in China.   The argument of the thesis is that these initiatives must be understood within the environment in which they are introduced. In the case of the Chinese online environment, individuals often have limited possibilities of acting anonymously. To explore how online identity registration affects citizens, a lab-in-the-field experiment was set up. Chinese university students were invited to engage with a government sponsored online forum under conditions of both anonymity and identity registration. Previous research suggests that anonymity would lead users of online fora to be more active and produce more content. This hypothesis was partly proven false by the experiment. This study shows that users who have their identities registered, sometimes even produce more content. The study also shows that registered users tend to act against their own preferences and participate more in nationalistic debates. The concluding discussion is focused on the wider implications of these effects. If citizens are incentivized to channel their dissatisfaction as loyalty, rather than voice or exit, they might become complicit in sustaining authoritarianism. Interviews with experiment participants show that open government initiatives primarily enable deliberative and collaborative autocracy when introduced in the Chinese online environment. This has the potential of increasing the amount of dissatisfaction that citizens channel as loyalty via mechanisms of authoritarian collaboration.
174

Next generation transduction pathways for nano-bio-chip array platforms

Jokerst, Jesse Vincent 24 October 2014 (has links)
In the following work, nanoparticle quantum dot (QD) fluorophores have been exploited to measure biologically relevant analytes via a miniaturized sensor ensemble to provide key diagnostic and prognostic information in a rapid, yet sensitive manner—data essential for effective treatment of many diseases including HIV/AIDS and cancer. At the heart of this “nano-bio-chip” (NBC) sensor is a modular chemical/cellular processing unit consisting of either a polycarbonate membrane filter for cell-based assays, or an agarose bead array for detection of biomarkers in serum or saliva. Two applications of the NBC sensor system are described herein, both exhibiting excellent correlation to reference methods ((R² above 0.94), with analysis times under 30 minutes and sample volumes below 50 [mu]L. First, the NBC sensor was employed for the sequestration and enumeration of T lymphocytes, cells specifically targeted by HIV, from whole blood samples. Several different conjugation methods linking QDs to recognition biomolecules were extensively characterized by biological and optical methods, with a thiol-linked secondary antibody labeling scheme yielding intense, specific signal. Using this technique, the photostability of QDs was exploited, as was the ability to simultaneously visualize different color QDs via a single light pathway, effectively reducing optical requirements by half. Further, T-cell counts were observed well below the 200/[mu]L discriminator between HIV and AIDS and across the common testing region, demonstrating the first reported example of cell counting via QDs in an enclosed, disposable device. Next, multiplexed bead-based detection of cancer protein biomarkers CEA, Her-2/Neu, and CA125 in serum and saliva was examined using a sandwich immunoassay with detecting antibodies covalently bound to QDs. This nano-based signal was amplified 30 times versus molecular fluorophores and cross talk in multiplexed experiments was less than 5%. In addition, molecular-level tuning of recognition elements (size, concentration) and agarose porosity resulted in NBC limits of detection two orders of magnitude lower than ELISA, values competitive with the most sensitive methods yet reported (0.021 ng/mL CEA). Taken together, these efforts serve to establish the valuable role of QDs in miniaturized diagnostic devices with potential for delivering biomedical information rapidly, reliably, and robustly. / text
175

Effects of ozonation/filtration on the raw water from Lake Mälaren / Effekter av ozonering/filtrering på råvattnet från sjön Mälaren

Larsson, Nina January 2004 (has links)
<p>Syftet med examensarbetet var att undersöka effekterna av ozonering och filtrering på råvattnet från sjön Mälaren. Studien är utförd i en pilotanläggning på Lovö vattenverk, Stockholm Vatten AB, under våren 2004.</p><p>En negativ effekt med den konventionella reningen är den stora konsumtionen av kemiska koagulanter. Kemikalieanvändningen leder till många transporter och processen producerar också ett slam som för närvarande transporteras till Mälaren. År 2001 byggdes en pilotanläggning på Lovö vattenverk för utveckling av nya processer, en av processerna är ozonering följt av olika filter.</p><p>Ozonering har använts i Europa i många år som desinfektion i slutet av dricksvattenreningsprocessen. Intresset för ozonering har ökat markant sista åren och idag används ozonet också i andra steg i processen. Förutom desinfektion har ozonet andra fördelar, som oxidation av järn och magnesium, mikroflockning, reduktion av lukt och smak samt är bra på att reducera färgen på vattnet. Mikroflockningen leder till att kemikalieanvändningen kan minska och i vissa fall tas bort helt.</p><p>Den här studien startade med en litteraturundersökning följd av försök med ozonering och filtrering i pilotanläggningen. De första undersökningarna sammanfattades med att ozonering följt av filtrering inte gav tillräckligt bra resultat och processen behöver ett komplement för att producera ett högklassigt vatten.</p><p>Undersökningen fortsatte med laboratorieanalyser för att undersöka effekterna av olika kemiska koagulanter. Resultatet visade att järnsulfat tillsammans med kalcium var ett bra alternativ och en lägre kemikaliedos kunde användas.</p><p>Efter implementering av kalcium och järnsulfat till pilotanläggningen testades olika ozondoser och olika järnsulfatdoser. Det bästa resultatet erhölls då man använde sig av en ozondos på 6 mg O3/l och en järnsulfatdos på 50-60 μmol/l. Denna mängd av järnsulfat är ca 60 % lägre än den dos som används vid den konventionella reningen på Lovö vattenverk.</p><p>Olika filter används i pilotanläggningen och för att förbättra resultatet provades även ett Filtralite-filter som biofilter istället för GAC-filtret. Jämförelsen mellan Filtralite-filter och GAC-filter visade på stora skillnader i parametervärden i början av studietiden. När bakteriepopulationen ökade i Filtralite-filtret blev skillnaderna mindre och i slutet av undersökningstiden var parametervärdena likartade. Det slutliga resultatet indikerar att Filtralite-filter kan vara ett bra alternativ som biofilter.</p> / <p>This Master thesis was made to investigate the effects of ozonation and filtration on raw water from Lake Mälaren. The study was performed in lab-scale as well as in a pilot plant at Lovö waterworks, Stockholm Water Company during spring 2004.</p><p>The conventional treatment at Lovö waterworks comes with a few disadvantages, such as large consumption of chemical coagulants. The chemical consumption leads to many transports and the treatment also produces a sludge which is, in present, returned to Lake Mälaren. In 2001 a pilot plant were built at Lovö waterworks for research on new treatment processes, and ozonation followed by filtration is one of them.</p><p>Ozonation has been used in Europe for several years as disinfection at the end of the drinking water treatment process. The interests of ozonation has increased significantly in recent years and today the ozonation is used in other steps in the drinking water treatment process. Except for the disinfection, ozone has other benefits such as oxidation of iron and manganese, microflocculation, reduction of taste and odour and it is also effective to reduce the water colour. The microflocculation leads to the fact that less or no coagulants need to be used in the process.</p><p>This study started with a literature overview followed by experiments on ozonation and filtration in the pilot plant. After the first experiments the conclusions were that the ozonation and filtration did not reach the same results as Lovö waterworks. To continue, jar tests were made to see the effects of different coagulants. The result indicated that ferric sulphate together with calcium addition (pH-adjustment) was a good alternative. Thereby a lower coagulant dose could be used.</p><p>When ferric sulphate and calcium were implemented into the pilot plant, different ozone doses and ferric sulphate doses were tested. The best results occurred when an ozone dose of 6 mg O3/l and a ferric sulphate dose of 50-60 μmol/l were used. This amount of ferric sulphate is approximately 60 % lower than that for the conventional treatment at Lovö waterworks. To produce ozone electrons are needed and energy consumption increases with approximately 66 % compared to the conventional treatment. The decrease in chemical dose and increase in energy demand gives a decrease of the total cost with 10 % compared to the conventional treatment. The results indicate that the treatment with ozonation, calcium addition and ferric sulphate as a coagulant is an alternative to the conventional treatment.</p><p>Different filters were used in the pilot plant and to improve the results a Filtralite-filter was tested instead of the GAC-filter as a bio filter. When comparing Filtralite-filter with the GAC-filter there were large differences between the filters at the beginning of the study. When the bacteria population in the Filtralite-filter had started to increase the differences became less. In the end of the experimental period the filters had similar conditions and Filtralite-filter may be a good alternative as a biofilter.</p>
176

Selective Isolation of Circulating Tumor Cells in Antibody-Functionalized Microsystems

Zheng, Xiangjun January 2011 (has links)
Attachment of circulating tumor cells in microfluidic devices functionalized with proper antibodies was studied. Under static experimental conditions, microchambers were utilized to study the parameters such as cell suspension concentration, incubation time or ambient temperature that may affect the binding of cell to the functionalized surfaces. Specific capture of cells from suspensions increases exponentially with incubation time and linearly with concentration within the tested range. Functionalizing a surface with counter-receptors enables capture of almost 100% of cells within 15 minutes incubation time at ambient temperature higher than 25°C. Suspending cells with different receptors, changing the counter receptors immobilized on the surface, or incubation the cell suspension at low ambient temperature result in a poor capture ratio. To illustrate the specific binding of target cells, various binary mixtures of target cancer and blood cells were incubated in the microchambers. The microsystem sensitivity, specificity and accuracy were determined as a function of the incubated cell concentrations. In general, the system specificity increases while the sensitivity decreases with increasing cell concentration; the accuracy of the system depends weakly on cell concentration within the tested range. The cell attachment dynamics in shear flow was studied by driving the MDA-MB- 231 or BT-20 cells through microchannels functionalized with EpCAM antibodies. The cell attachment ratio was experimentally determined at different flow rates. A modeling system based on Stokesian as well as cell-adhesive dynamics is adopted to analyze the cell motion. The cell motion is modeled as a rigid sphere, with receptors on its surface, moving under shear flow above a surface immobilized with ligands. The system is described mathematically by the Langevin equation, in which the receptor-ligand bonds are modeled as linear springs. Primarily depending on the applied flow rate, three distinct dynamic states of cell motion have been observed: free motion, rolling adhesion, and firm adhesion. The fraction of cells captured due to firm adhesion, defined as attachment ratio, depends on the applied flow rate with a characteristic value that increases with either cellreceptor or surface-ligand density. Utilizing this characteristic flow rate as a scaling parameter, all measured and calculated attachment ratios for different receptor and ligand densities collapse onto a single exponential curve. Binary mixtures of target MDA-MB-231 cells and non-target BT-20 cells were driven through anti-cadherin-11 functionalized microchannels to study the selective isoaltion of target cells from binary mixtures. The system sensitivity is very high, above 0.95, while the specificity is only moderately high, about 0.85, essentially independent of the relative concentration of the target and non-target cells in the binary mixture. An attachment/detachment flow field pattern is proposed to enhance the system specificity. Utilizing this flow pattern with a 1:1,000 MDA-MB-231:BT-20 binary cell mixture, the microfluidic system specificity increased to about 0.95 while the sensitivity remained above 0.95. In order to obtain high experimental throughput allowing lower relative concentration of target cells, a microchannel array which enables processing samples containing about 510⁵ cells with a minimum target cell concentration ratio of 1/100,000 was designed and fabricated. To demonstrate selective isolation of target cells, binary mixtures of BT-20 cells and MIA PaCa-2 cells were driven through microchannel arrays functionalized with EpCAM antibodies; the EpCAM positive BT-20 cells served as target cells and the EpCAM negative MIA PaCa-2 cells as non-target cells. The relative concentration ratio of target/non-target cells varied from 1:1 to 1:100,000. The sensitivity was close to 1.0 while the specificity was also high, about 0.95. The additional detachment step, with a faster flow rate, enhanced the specificity to about 0.985. Initial results of two sets of experiments are reported as preliminary studies for future work. In the first set of experiments, whole blood samples from healthy donors were spiked with a known number of BT-20 cells at a concentration of 500 CTCs per milliliter blood or 50 CTCs per milliliter blood. After a pretreatment to enrich the CTCs, the samples were driven through microchannel arrays functionalized with anti-EpCAM. For both samples, around 55% of the target CTCs were captured in the microchannel arrays. The second set of experiments was dedicated to characterization of target cells exposed to applied shear stress. BT-20 or MDA-MB-231 cells were driven through microchannels functionalized with EpCAM antibodies to allow target cell attachment; then, a high flow rate was applied to detach the captured cells. The detached cells were collected and cultured in an incubator to test their viability. For both cell lines, the majority of the captured CTCs collected from the microchannels were viable. The images taken after three and seven days of culture demonstrate continuous cell growth and division.
177

Detection and Monitoring of Pathogens in Animal and Human Environment by a Handheld Immunosensor and CFD Simulation

KWON, HYUCK JIN January 2011 (has links)
This research demonstrates technology for detection of pathogens and environmental monitoring using a handheld optofluidic immunosensor and CFD simulation. The current methods such as ELISA and PCR require few hours for identification which means it is unavailable for early-monitoring. The use of a near-real-time, handheld biosensor device in a real animal/human environment is the key to monitoring the spread of dangerous pathogens. A 3-D computational fluid dynamics (CFD) simulation is needed to track the pathogens within an environment.This dissertation has four papers that demonstrate technologies for the detection and monitoring of pathogens and the miniaturization of these detection systems for in field applications with a handheld immunosensor and CFD simulation.In the first paper, an environmental prediction model was developed for optimal ventilation in a mushroom house by using sensible heat balance and 3-D CFD method. It is shown that the models can be used for farmers to predict the environmental conditions over different locations in a mushroom house.In the second paper, a field lab-on-a-chip system was constructed to detect mouse immunoglobulin G and Escherichia coli by using light scattering detection of particle immunoagglutination. Antibody-conjugated particles were able to be stored in a 4°C refrigerator for at least 4 weeks and to be lyophilized as a powder form for the storage in room temperature.In the third paper, rapid monitoring of the spreads of porcine reproductive and respiratory syndrome virus (PRRSV) was attempted using samples collected from nasal swabs of pigs and air samplers within an experimental swine building. An optofluidic device containing liquid-core waveguides was used to detect. It is shown that the developed optofluidic device and 3-D CFD model can serve as a good model for monitoring the spread of airborne viruses within animal and human environments.In the fourth paper, a handheld optofluidic immunosensor was developed for rapid detection of H1N1/2009 virus inside a 1:10 scale mock classroom. Both miniature spectrometer and cell phone camera were used as detector. A 3-D computational fluid dynamics (CFD) model was developed to track the transport/distribution of H1N1/2009 viruses, and corresponded very well with immunosensor readings.
178

Chemically Programmed  Memory Card and PC Connected Memory Card Reader

Vadakke Kunninmel, Gokuldev January 2013 (has links)
Inkjet-printed memory cards have been developed previously by re-searchers at Mid Sweden University but, these did possess some limita-tions, as each resistive memory cell required one physical contact and the resistances were designed to be electrically programmed.This work overcomes the above limitations by developing chemically programmed printed memory cards and a PC connected memory card reader. Printed memory cards are inexpensive and are developed by inkjet printing the nano-silver ink onto the photo paper substrate. A matrix readout method is used to increase the num-ber of memory cells and, by using a chemical solvent, the resistances were programmed to the desired resistance values and, for which, each resistance value represents data on the cards, called, write once read many (WORM) memories. The memory card reader was developed to access the data (resistance value) of the memory card and also to trans-mit the data to a LabVIEW graphical user interface for displaying the resistance values. By using multiple resistance steps, in which each step represents a different state, it is possible to create a number of possible selectable combinations which can be programmed at a later stage for developing applications.
179

Development of a Microfluidic Platform for Trace Lipid Analysis

Davic, Andrew Paul 04 May 2017 (has links)
The field of lipidomics encompasses the study of pathways, networks, and functionality of cellular lipids in biological systems. The lipid subclass, primary fatty acid amides, are crucial to nervous system signaling, receptor function, and numerous other physiological roles. Chapter 1 details these bioactive properties of several well-studied primary fatty acid amides as well as their biosynthesis, degradation, and most common analysis techniques. As these bioactive lipids are endogenously present in trace and ultra-trace abundancies, the field of microfluidics presents an attractive alternative analysis system to incorporate minimization of sample and reagent usage, analysis cost reduction, highly sensitive detection pairing, and decreased analysis time, all while limiting sample handling. Chapter 2 provides a microfluidics-based review of common device fabrication techniques, droplet microfluidics, and detection systems. Current primary fatty acid amide analysis techniques have detection limits on the periphery of endogenous concentrations, presenting the need for a more sensitive detection system, such as fluorescence. Chapter 3 serves as the foundation in developing methodology to analyze these amides and their conjugate fluorescently-tagged primary amines. Chapter 4 focuses on the development of a microfluidic platform capable of efficient on-chip fluorescent tagging reactions and the coupling of a highly sensitive laser induced fluorescence detection system capable of detection limits several orders of magnitude lower than currently employed mass spectrometry techniques. In addition, the appendix details the method development for the quantitative analysis of the anti-inflammatory and anti-cancer drug, celecoxib, uptake into novel drug delivery vehicles. / Bayer School of Natural and Environmental Sciences; / Chemistry and Biochemistry / PhD / Dissertation;
180

Visualizing personal data in context: an on-calendar design strategy for behaviour feedback

Huang, Dandan 31 August 2016 (has links)
Visualization tools are frequently used to help people understand everyday data in their lives. One such example is visualization in behaviour feedback tools. Behaviour feedback tools are used to try to help people improve their health or personal well-being or to carry out sound environmental sustainability practices. However, understanding and reasoning about personal data (e.g., pedometer counts, blood pressure readings or home electricity consumption) or gaining a deeper understanding of one's current practices and learning how to make a change can be challenging when using data alone. My literature review of this field showed that two of the main challenges in actual practice are providing a context in which to reason about the data and reducing the cost of maintenance to fit those tools into everyday life routines. Thus, I propose to integrate time-varying feedback data within a personal digital calendar. This combination of calendar and feedback data can provide contextual information to interpret data and make the data accessible in an attentionally ambient way that is suitable for maintaining awareness. I propose that the familiarity and common practice of using digital calendars can minimize the cost of learning and maintenance for people and easily fit into one's daily life routines. The viability of this approach was confirmed in my quantitative lab experiments. The results showed that visualization of feedback data integrated on a digital calendar is comprehensible, and it does not interfere with regular calendar use with proper visual encodings. After confirming the viability of my proposal, I implemented the on-calendar visualization as a web application that was synchronized with Google Calendar API and a real-time feedback data stream. To further investigate this approach in a real life situation, I deployed the application in the field for longitudinal field studies: two case studies as pilot deployment and an eight-week field study. Results showed that people liked the idea of integrating feedback data into their personal digital calendars. It required a low cost in learning and maintenance. The calendar events provided rich context for people to visualize and reason about their feedback data. The design enabled people to quickly identify and explain repeated patterns and anomalies. Meanwhile, I found that people's existing information use habits (in this case, how they use digital calendars) can highly influence the effectiveness of the feedback design. Moreover, I derived a feedback model that identifies basic components in feedback design and illustrates the role of feedback tools. With that I articulated possible design barriers that could prevent ongoing use of feedback tools. Reflecting on the effects of the on-calendar design approach, I discussed design implications inspired by this work. This work introduces a reflective approach in feedback design that can easily fit into people's existing information ecosystem (specifically, a personal digital calendar in this work). The main contributions of this thesis are: the first systematic literature review of personal visualization design used in everyday life; the design and implementation of an on-calendar design that integrates feedback data on people's personal digital calendars to provide context for reasoning and support easy access for ongoing use; the extended definition of ambience from spatial location to attentional demand; a viability study to confirm the on-calendar design approach; longitudinal studies to investigate the effects of the on-calendar design approach and the feedback model of design mechanism to inspect ongoing factors in feedback designs. / Graduate / 0984, 0384 / dhuangca@gmail.com

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