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Dissertations / Theses on the topic 'Eye diagram'
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Zheng, Shijie M. Eng Massachusetts Institute of Technology. "A low cost asynchronous eye diagram reconstruction system for high speed links." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/85233.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2013.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (pages 97-98).<br>As link communication data rate increases, there is an increasing need for a more cost eective way to test and monitor signal integrity in link communication systems. Specifically, eye diagrams are valuable visual aids to analyze and quantify digital signal quality. This thesis presents a novel low cost eye diagram reconstruction system using asynchronous undersampling technique, which solves a key problem in performance monitoring in systems where synchronous sampling is not available, such as video switches. Existing works are studied and compared to this work in performance and cost. The proposed system is designed as a system-on-chip (SOC) and contains an undersampling ADC, aliased frequency estimator and a simple reconstruction algorithm. Major building blocks are implemented and simulated in 65nm CMOS process. Extensive system level analysis and simulations demonstrate functionality and performance of the system working at 10Gb/s maximum data rate.<br>by Shijie Zheng.<br>M. Eng.
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Flesher, Paul Michael. "Proof validation in Euclidean geometry: a comparison of novices and experts using eye tracking." Diss., Kansas State University, 2018. http://hdl.handle.net/2097/38778.
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Doctor of Philosophy<br>Department of Mathematics<br>Andrew G. Bennett<br>This dissertation investigates and compares the methods of proof validation utilized by novice and expert mathematicians within the realm of Euclidean geometry. With the use of eye tracking technology, our study presents empirical evidence supporting claims previously studied only through the use of verbal protocols.
Our investigation settles a series of contentious results surrounding the practical implementation of the generalized validation strategy called zooming out (Inglis and Alcock, 2012; Weber, Mejia-Ramos, Inglis, and Alcock, 2013). This strategy analyzes the overall structure of a proof as an application of methods or logical chunks. Settling the debate through use of longer and more complicated proofs devoid of blatant errors, we found that validators do not initially skim-read proofs to gain structural insight. We did however confirm the practical implementation of zooming out strategies.
The literature identifies within the proof validation process specific differences between novices and experts. We are interested in a holistic understanding of novice and expert validations. We therefore present the direct comparison of entire validation processes that assess the similarity of novice and expert overall validation attempts. We found that the validation processes of novices and experts share a certain degree of similarity. In fact novices tend to be closer to experts than to other novices. And when validations are clustered, the groups are heterogeneous with regard to mathematical maturity.
Our investigation expands the proof validation literature by including diagrams in the proof validation process. We found that experts tend to spend more time proportionally on the diagram than novices and that novices spend more time on the text. Furthermore, experts tend to draw more connections within the diagram than novices as indicated by a higher proportion of attentional changes within the diagrams. Experts seem to draw on the power of visualizations within the mathematics itself, spending more time on conceptual understanding and intended connections.
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Sharif, Bonita. "Empirical Assessment of UML Class Diagram Layouts Based on Architectural Importance." Kent State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=kent1271679781.
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Lee, Jeffrey C. "ARCHITECTURAL CONSIDERATIONS FOR A VARIABLE BIT RATE DATA ACQUISITION TELEMETRY ENCODER." International Foundation for Telemetering, 2007. http://hdl.handle.net/10150/604502.
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ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada<br>Modern telemetry systems require flexible bit rate telemetry encoders in order to optimize mission formats for varying data rate requirements and/or signal to noise conditions given a fixed transmitter power. Implementing a variable bit rate telemetry encoder requires consideration of several possible architectural topologies that place different system requirements on data acquisition modules within the encoder in order to maintain adequate signal fidelity of sensor information. This paper focuses on the requirements, design considerations and tradeoffs associated with differing architectural topologies for implementing a variable bit rate encoder and the resulting implications on the encoder systems data acquisition units.
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Quinteros, Milton I. "Design and Software Validation of Coded Communication Schemes using Multidimensional Signal Sets without Constellation Expansion Penalty in Band-Limited Gaussian and Fading Channels." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1937.
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It has been well reported that the use of multidimensional constellation signals can help to reduce the bit error rate in Additive Gaussian channels by using the hyperspace geometry more efficiently. Similarly, in fading channels, dimensionality provides an inherent signal space diversity (distinct components between two constellations points), so the amplitude degradation of the signal are combated significantly better.
Moreover, the set of n-dimensional signals also provides great compatibility with various Trellis Coded modulation schemes: N-dimensional signaling joined with a convolutional encoder uses fewer redundant bits for each 2D signaling interval, and increases intra-subset minimum squared Euclidean distance (MSED) to approach the ultimate capacity limit predicted by Shannon's theory. The multidimensional signals perform better for the same complexity than two-dimensional schemes. The inherent constellation expansion penalty factor paid for using classical mapping structures can be decreased by enlarging the constellation's dimension.
In this thesis, a multidimensional signal set construction paradigm that completely avoids the constellation expansion penalty is used in Band-limited channels and in fading channels. As such, theoretical work on performance analysis and computer simulations for Quadrature-Quadrature Phase Shift Keying (Q2PSK), Constant Envelope (CE) Q2PSK, and trellis-coded 16D CEQ2PSK in ideal band-limited channels of various bandwidths is presented along with a novel discussion on visualization techniques for 4D Quadrature-Quadrature Phase Shift Keying (Q2PSK), Saha's Constant Envelope (CE) Q2PSK, and Cartwright's CEQ2PSK in ideal band-limited channels. Furthermore, a metric designed to be used in fading channels, with Hamming Distance (HD) as a primary concern and Euclidean distance (ED) as secondary is also introduced. Simulation results show that the 16D TCM CEQ2PSK system performs well in channels with AWGN and fading, even with the simplest convolutional encoder tested; achievable coding gains using 16-D CEQ2PSK Expanded TCM schemes under various conditions are finally reported.
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Dorociak, Petr. "Vliv polarizační disperze na chybovost optického kanálu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217496.
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Master’s thesis engages in the impact of polarization mode dispersion on optical communication system. Polarization mode dispersion is mathematically described by Stoke’s and Jone’s space and ensure the theoretic causes of the rise of polarization mode dispersion that are divided on the external and internal effects. On the basis of these effects grow up a differential group delay (DGD) which makes causes that individual polarization modes have between them a time delay and limitation of maximum bit rate. Then master´s thesis analyses the influence of the polarization mode dispersion on the pulse enlargement and on the modulation signal. In this work, there are described the most applicated optical modulation formats. Polarization mode dispersion has also influence on the bit error rate of optical fibre link and closing of eye diagram too. Eye diagram is used to view the transmission characteristics and diagnoses the channel errors. Eye diagram is connected with the definitions as a bit error rate (BER) and signal-to-noise ratio (SNR) that are explained in this work too. Following the gained experiences it was designed an useful graphic interface to display the effect of the polarization mode dispersion on the transmitted signal. Realization of the graphic interface is created in the program MATLAB. In Matlab-Simulink are created six models according to the kind of modulations with characteristic AWGN (Additive White Gaussian Noise) channel. Program was tested for a typical values. In all calculations it is counted only with the losses that are caused by the polarization mode dispersion. It is not calculated with the losses that are caused by a chromatic dispersion and attenuation. At the end of this work are evaluated all types of modulation formats depending on the polarization mode dispersion, optical fibre length, price and complexity of the realization. Atteined results of my master’s thesis are compared with two foreign articles.
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Fitzhugh, Shannon Leigh. "The Coherence Formation Model of Illustrated Text Comprehension: A Path Model of Attention to Multimedia Text." Diss., Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/210583.
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Psychology<br>Ph.D.<br>The study reported here tests a model that includes several factors thought to contribute to the comprehension of static multimedia learning materials (i.e. background knowledge, working memory, attention to components as measured with eye movement measures). The model examines the effects of working memory capacity, domain specific (biology) and related domain (geoscience) background knowledge on the visual attention to static multimedia text, and their collective influence on reading comprehension. A similar model has been tested with a previous cohort of students, and has been found to have a good fit to the data (Fitzhugh, Cromley, Newcombe, Perez and Wills, 2010). The present study tests the efficacy of visual cues (signaling) on the comprehension of multimedia texts and the effects of signaling on the relationships between cognitive factors and visual attention. Analysis of Covariance indicated that signaling interacts with background knowledge. Signaling also changes the distribution of attention to varying components of the multimedia display. The path model shows that signaling alters the relationship between domain specific background knowledge (biology) and comprehension as well as that of related background knowledge (geoscience) on comprehension. The nature of the relationships indicates that the characteristics of the reading material influence the type of background knowledge that contributes to comprehension. Results are discussed in terms of their application to a classroom setting.<br>Temple University--Theses
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Matušík, Lukáš. "Technologie datových přenosů v optických přístupových sítích FTTx." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218199.
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The objective of diploma thesis is describe problems connected with designed of FTTX networks and bring the reader problems of data transmission in optical acces networks the type of PON. In the introduction are mentinoned individual technologies that already operate, and there are describe advantages disadvantages of the use topology point-to-point and point-to-multipoint. In the following chapters are dealt with problems with data broadcasting in the direction from final participant. In the other part of diploma thesis are described elements, that were used for the proposed transmission route. The own PON acces network was presented on the basis information obtained by comparing the various networks and the elements involved in them. The network presented in conclusion diploma thesis is involved in topology point to multipoint. This transmission route is simulated in the program that allows the involvement of network by the user’s need with real values. The acces network is simulated for different transmission speed and different distances. The assesment of created optical route results from the measured values, theirs source is program OptiSystem, these values are summarized in the final chapter.
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Zhang, Yongjian. "Investigation of electrical and optical characterisation of HBTs for optical detection." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/investigation-of-electrical-and-optical-characterisation-of-hbts-for-optical-detection(3c47e08f-9201-4465-b2b5-268aa0360309).html.
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In this thesis, a detailed study of the electrical and optical characterisations of Heterojuction Bipolar Transistors (HBTs) for optical detection is presented. By comparing both DC and optical characterisations between In0.49Ga0.51P/GaAs Single Heterojuction Bipolar Transistors (SHBTs) and Double Heterojuction Bipolar Transistors (DHBTs), the advantages of using the DHBT as a short wavelength detector are shown. Phenomena related to the base region energy band bending in the DHBT caused by a self-induced effective electric field is discussed and its effects on the performance of the device are elaborated. The use of an eye diagram has been employed to provide requisite information for performance qualification of SHBT/DHBT devices. These give a more detailed understanding compared to conventional S-parameters method. A detailed comparison of In0.49Ga0.51P/GaAs SHBT and DHBT performance using an eye diagram as a functional tool by adopting a modified T-shaped small signal equivalent circuit are given. By adopting this modified T-shaped small signal equivalent circuit, the use of In0.49Ga0.51P/GaAs Double Heterojuction Phototransistors (DHPT) as a short wavelength photodetector is analysed. It is therefore shown that an eye diagram can act as a powerful tool in HBTs/HPTs design optimisations, for the first time in this work. In order to predict the spectral response (SR) and optical characterisations of GaAs-based HPTs, a detailed theoretical absorption model is also presented. The layer dependence of an optical flux absorption profile, along with doping dependent absorption coefficients are taken into account for the optical characterisation prediction. With the aim of eliminating the limitation of current gain as a prerequisite, analytical modelling of SR has been developed by resolving the continuity equation and applying realistic boundary conditions. Then, related physical parameters and a layer structure profile are used to implement simulations. A good agreement with the measured results of the Al0.3Ga0.7As/GaAs HPT is shown validating the proposed theoretical model.
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Horský, Tomáš. "Rozšíření optického vláknového přenosového systému." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442378.
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The diploma thesis describes the elaboration of a program for the simulation of an optical transmission path. The work introduces the basic parameters of optical transmission, such as attenuation, dispersion and bandwidth. Furthermore, the techniques of line code and error detection are described in the work, especially a cyclic redundancy sum. The key parameter of this thesis is dispersion of the optical signal. The work includes the characteristics of the eye diagram and its analysis. The resulting program can also be used to measure the real transmission route and its parameters.
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Kosmák, Václav. "Analýza stávajícího kluzného kontaktu, kvalitativních a funkčních vlastností "kroužkostrojů"." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-318099.
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Thesis deals with the analysis of the sliding contact in the ring mill. It focuses on the assessment of the effect of the current load on the sliding contact, the assessment of the signal transmission quality from the static to the rotara part of the ring contact slide contact.
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Yusuf, Patel Dawoodi Shehnaaz. "Assessing the Comprehension of UML Class Diagrams via Eye Tracking." Kent State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=kent1194997886.
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Nazli, Bilgic, and Sofia Kiriaki Vulgari. "Comparison of Two Eye Trackers for the Visualization of Eye Tracking Data in Node-Link Diagrams." Thesis, Linnéuniversitetet, Institutionen för datavetenskap (DV), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-55733.
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The usage of eye trackers is becoming more and more popular in the field of information visualization. In this project two eye trackers, The Eye Tribe nd Mirametrix S2, are used to obtain eye tracking data for visualizations. It is planned to use the eye trackers with OnGraX, a network visualization system, where they will provide data for the implementation of visualizations, specifically, heatmaps. OnGraX already uses heatmaps to show regions in a network that have been in the viewport of the user. One aim of this thesis will be the comparison between the two eye trackers, and if the use of eye tracking data gives better results thatn the already existing viewport-based approach. At the same time, we provide the foundation for adaptive visualizations with OnGraX. Our research problem is also of interest for visualization in general, because it will help to improve and develop eye tracking technology in this context. To support the outcome of our implementation, we carried out a user study. As a result, we concluded that one of the two eye trackers appears to have more capabilities than the other, and that using the eye tracking data is a more preferred way of depicting the heatmaps on OnGraX.
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Lin, Yu Ying. "Effects of Detailed Diagrams on Science Learning." Kyoto University, 2019. http://hdl.handle.net/2433/242309.
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Venkatesha, Divya. "Small signal characterisation of microwave active and passive devices using eye diagrams." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.625128.
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This thesis presents new results for the use of eye diagrams as a functional tool to study the response of components, which may be a simple transistor, an amplifier or even the entire transreceiver system, particularly in the digital environment. Conventionally, S-parameter methods are used to evaluate the performance of devices at high frequencies but these do not offer complete performance characteristics, especially when the components are used in digital applications. In this project it is shown that the eye diagram can be effectively employed to provide an additional measurement tool to quantify the performance of active and passive components. The eye diagram, which have always been used as a mere visual tool in the past, has been shown in this work to be a very powerful tool, which helps in the optimization of components, especially for use in optical applications. In this work, eye diagrams have been generated, measured and also simulated for different passive components, i.e., transmission lines and active components i.e., InGaP/GaAs HBTs and GaAs pHEMTs. It is shown that various eye parameters relate directly to the physics of the components under test. Sensitivity analysis has also been carried out to study the switching characteristics of components using the eye diagrams. Using both experimental and simulation data, in this work it is shown that the eye diagram parameters can be studied to provide feedback to further optimize the components under test. Various parameters of both active and passive components have been measured and evaluated providing a comprehensive study of their behaviours and the way forward to optimize the structure of components for generating improved eye characteristics for digital applications. The measured results are also validated by simulations using Agilent's Advanced Design System. Small signal parameters of both HBTs and pHEMTs have been extracted using direct extraction method through IC-CAP and these were used in the simulation of eye diagrams. The procedures developed in this study would assist in the implementation of techniques to improve microwave component performance based on the feedback from the eye diagram analyses and to develop methodologies to build systems based on the eye diagram specifications.
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Kilic, Ozkan. "Cognitive Aspects Of Conceptual Modeling Diagrams: An Experimental Study." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608849/index.pdf.
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This thesis is about diagrammatic reasoning and error-finding in conceptual modeling diagrams. Specifically, the differences of the cognitive strategies and behaviors of notation-familiar participants versus domain-familiar participants working on conceptual modeling diagrams are inspected. The domain-familiar participants are experienced in the topic being represented, but they do not have any formal training in software development representations. On the other hand, the notation-familiar participants are educated in software representations, but unfamiliar with the topic represented. The main experiment and the follow-up experiment also aim to study how some properties of diagrams affect the error-finding behaviors. The participant groups&rsquo<br>performances in the main experiment are investigated and compared by the analysis of verbal protocol data and eye movement data. The combination of the two different methods enhances detailed analyses. In the follow-up experiment, only eye movement data is involved to evaluate how some properties of diagrams affect problem-solving. By means of both experiments, it is concluded that diagrammatic complexity has a negative effect on reasoning whereas the degree of causal chaining improves diagrammatic reasoning. In the main experiment, some differences in the diagrammatic reasoning processes between the groups are observed, too. The notation-familiar participants are observed to be more successful in error-finding although they are unfamiliar with the topic. This study underlines the interaction of cognitive science and software engineering by integrating eye movement data, verbal protocol analysis and performance data into the cognitive inspection of software engineering notations.
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Fernandes, Leandro Henrique Oliveira. "Simulação de fenômenos óticos e fisiológicos do sistema de visão humana." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-09052008-161636/.
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O ganho crescen te de desempenho nos computadores modernos tem impulsionado os trabalhos científicos nas áreas de simulação computacional. Muitos autores utilizam em suas pesquisas ferramentas comerciais que limitam seus trabalhos ao esconder os algoritmos internos destas ferramentas e dificultam a adição de dados in-vivo nestes trabalhos. Este trabalho explora esta lacuna deixada por aqueles autores. Elaboramos um arcabouço computacional capaz de reproduzir os fenômenos óticos e fisiológicos do sistema visual. Construímos com superfícies quádricas os modelos esquemáticos do olho humano e propomos um algoritmo de traçado de raio realístico. Então realizamos um estudo nos modelos esquemáticos e a partir deles mais a adição de dados in-vivo obtidos de um topógrafo de córnea extraímos informações óticas destes modelos. Calculamos os coeficientes e Zernike dos modelos para tamanhos diversos de pupila e obtivemos medidas de aberração do olho humano. Os resultados encontrados estão de acordo com os trabalhos relacionados e as simulações com dados in-vivo estão consoantes com as produzidas por um aparelho de frente de onda comerciais. Este trabalho é um esforço em aproveitar as informações adquiridas pelos equipamentos modernos de oftalmologia, além de auxiliar o entendimento de sistemas visuais biológicos acabam também em auxiliar a elaboração de sistemas de visão artificial e os projetistas de sistemas óticos<br>The increase in performance of the modern computers has driven scientific work in the areas of computer simulation. Many authors use in their research commercial tools that use embedding algorithms, which sources are not provided, and it makes harder and sometimes impossible, the development of novel theories or experiments. This work explores this gap left for those authors. We present a computational framework capable to reproduce the optical and physiological phenomena of the human visual system. We construct schematical models of the human eye from quadrics surfaces and consider an algorithm of realistic ray tracing. Afterward, we performed a study on schematics models and in addition we introduce, in these models, in-vivo data obtained from corneal topography machine and extract optical information. We calculate the Zernike coefficients in the models for different sizes of pupil and measures of aberration of the human eye. The results are in agreement with related work and simulations with in-vivo data are according with the produced by a commercial wave-front device. This work is an effort in using to advantage the information acquired for the modern equipment of ophthalmology, besides assisting the understanding of biological visual systems, it also helps the development of artificial vision systems and the designing of optical systems
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Chen, PoYun. "Role of Ionic Liquid in Electroactive Polymer Electrolyte Membrane for Energy Harvesting and Storage." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1590688110146547.
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Milet, Tomáš. "Grafické intro 64kB s použitím OpenGL." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2012. http://www.nusl.cz/ntk/nusl-236545.
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This thesis deals with the creation of the intro with limited size. This work describes methods for reducing the size of the final application. The main part describes methods for generating graphic content and methods for its animation. It deals with creation of textures and geometry. Another part is aimed on the physical simulation of particle and elastic systems.
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Pan, Chia-Shuo, and 潘家碩. "Prediction Technique of Eye-Diagram in High-Speed Interconnections." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/ud8j86.
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碩士<br>大同大學<br>通訊工程研究所<br>102<br>Following the high technology industry increased. We need more quantity of transmission data. And the digital signal data speed transmission are faster and faster. We have to know the high speed and high frequency have the effect for the transmission.
Eye-diagram is more important than before, because the Eye-diagram was made by the Pseudo-random bit sequence (PRBS) which is the random digital signal for testing the signal integrity. But the transmission lines measurement or connectors measurement also face the effect from the transmission line between instrument and the fixture. In this paper we testing the relationship of the impedance and Eye-diagram, we used the Time Domain Reflectometry (TDR) to measure the time domain result. We can get only the part of impedance we need where the device under test (DUT) located. And with the help of the equivalent circuit software in our laboratory. We can get the needed parameter of the device under test (DUT) characteristic without the other transmission lines effect.
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Lin, Jeng-Hau, and 林政豪. "Algorithm for Determining Eye-Diagram Characteristics of Lossy Transmission Lines." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/98957819086681682287.
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碩士<br>國立臺灣大學<br>電信工程學研究所<br>95<br>The major theme of this thesis focuses on the methodology for the eye-diagram prediction of lossy transmission lines. The finite conductivity of the metal conductor and the loss due to displacement current and leakage current is the two primary factors to affect the eye diagram at the receiving end of transmission line. After obtaining the two important parameters that decide the impulse response by researching into the mechanism of loss of transmission line, this thesis applies time domain signal processing to develop the methodology to predict the eye diagram fast and accurately.
The thesis proposes the input signal pattern that generates the worst eye diagram at the receiving end when the mismatch effects at both ends aren’t serious, or the loss of transmission line is obvious. Because the transmission line model incorporate with the values of elements derived by the mechanism of loss in frequency domain is non-causal in time domain, the thesis propose an approximate mathematic solution by applying the Kramers-Kronig relations on the problem of causality. By using the two important parameters in the causal impulse response, the thesis develop the methodology of prediction. Finally, the measurement in frequency domain with vector network analyzer and time domain with digital oscilloscope and pattern generator shows the accuracy of this methodology.
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Cheng, Yung-Shou, and 鄭詠守. "Eye-Diagram Determination and Equalization Techniques for High-Performance Backplane Interconnect System." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/32458697434055216970.
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博士<br>國立臺灣大學<br>電信工程學研究所<br>101<br>This dissertation focuses on the developments of fast eye-diagram analyses and equalization techniques for solving the signal-integrity problems caused by the inter-symbol interference (ISI) in the high-performance backplane interconnect system.
In the beginning, a worst-case eye-diagram analysis which relates to the step response of the transmission-line system is presented to quickly and accurately evaluate the electrical performance for the general interconnect systems. With the help of the prediction approach, the bounded voltage margins for the worst-case logic 1-state and 0-state are derived analytically. In addition to introducing how to obtain the worst-case bit patterns form the given step response, several examples are shown to demonstrate the accuracy of the developed approach.
Secondly based on the finite-impulse response (FIR) filter as the transmitter pre-emphasis, a new design algorithm to directly optimize the eye diagram is proposed to counteract ISI in the high-speed data transmission. It is found that not only the frequency-dependent loss but also the multiple reflections due to impedance mismatch contribute much to ISI. Therefore, a systematic method is proposed to efficiently design FIR filters for the best eye-diagram improvement. The optimal sets of tap coefficients and numbers are thus determined by the direct eye-diagram optimization according to the target eye-masks as the objective function. Subsequently, the equalization results for counteracting the multiple reflections and lossy material problems are given to demonstrate the remarkable mitigation of ISI effects. Experimental results are also presented to validate the efficiency of the proposed method for the elimination of the ISI problems due to the multiple reflections and frequency-dependent loss.
Furthermore, a passive FIR filter design is proposed to realize the de-emphasis function by taking the advantage of reflections under the additional inserting stub. The relations between the synthesized tap coefficients and the corresponding design parameters (RT, RS, Zh) are derived analytically and thus a universal design chart is well established to facilitate the passive FIR filter design. The passive solution has the advantages of reducing the power consumption of the transmitters and achieving the eye-diagram improvement efficiently.
Finally, the systematic integration of signal-integrity aware layouts and the new continuous-time linear equalizer (CTLE) are proposed for enhancing the high-performance backplane interconnects system. First, the SI-aware layouts of patterned ground structure and capsule-shaped anti-pad are presented to enhance the connector performance. In addition, a new differential CTLE by taking the advantage of differential via-stubs is proposed to restore the eye-diagram deterioration in serial I/O links. Their application for a 117.5-cm SATA-II link demonstrates the significant improvement in the eye height and timing jitter. Furthermore, a viable approach is suggested to successfully re-open the eyes while the data rate increases from the current 3 Gb/s to 12 Gb/s. The measurement results are also provided to validate the proposed design concepts.
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Guo, Wei-Da, and 郭維德. "Eye-Diagram Analysis and Compensation Design of PCB-Scale Lossy Transmission Lines." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/88660695044972317012.
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博士<br>國立臺灣大學<br>電信工程學研究所<br>97<br>As the speed of digital signal increases toward multi-gigabit range, many non-ideal effects, such as reflection noise, crosstalk noise, transmission-line losses, and simultaneous switching noise, previously regarded to be negligible in the design of system interconnect have become the critical design challenges for satisfying the requirements of signal integrity (SI), power integrity (PI), and electromagnetic interference (EMI). Among them, the significant one is the frequency-dependent transmission-line losses that mainly come from the finite conductivity of imperfect conductor and the naturally electric polarization of dielectric material. The thus induced dispersion will exhibit a relative long-tail response on the transmitted signal. In other words, the lossy lines may cause serious inter-symbol interference (ISI) problem, resulting in the occurrence of poor eye-diagram performance or even the incorrect functionality of logic circuits, especially for the digital systems with the long-distance data transmission inside.
In this thesis, a fast methodology that employs only two anti-polarity one-bit data patterns as input signal is first proposed to simulate the worst-case eye diagram for the transmission- line system with a monotonic step response. Based on the assumption of a low-loss line, the impulse responses of lossy lines can be divided into three different mechanisms, which relate to the propagation delay, the conductive loss, and the dielectric loss, respectively. To resolve the causality problem in the transient analyses, the Kramers-Kroning (K-K) relations are utilized to refine the deficiency regarding the derived impulse response for the dielectric loss. Two design graphs for the worst-case eye-diagram characteristics vs. An and Bn, the quantification factors of conductive and dielectric losses, respectively, are constructed accordingly. Besides, the parametric analyses for the signal rising edges indicate that the effects of signal contents at the higher frequencies is negligible in the prediction of eye-opening profiles, while the unit interval in the pulse train is critical. As for the specified eye mask, both design graphs can be used to evaluate the maximally usable length of lossy transmission lines and if a designed system is workable. Favorable agreements shown in the eye-diagram comparisons with the HSPICE simulation and measurement results have validated the correctness and practicability of the present methodology.
In order to compensate the eye-diagram performance degraded by the transmission-line losses, this thesis introduces two popular passive compensation schemes: one is the passive equalizer, and the other is the reflection gain induced by the insertion of the high-impedance element, i.e. inductance or high-impedance transmission line, into the load termination. The complete design methodologies for the two methods are well discussed.
For the design of passive equalizer, a DC-level adapting method is proposed to determine the optimum DC level of the equalized response. The high-pass response that requires to be realized by the passive equalizer can then be obtained. RLC equalizer circuit is first adopted to avoid violating the impedance matching condition. A design method has been established to conveniently extract the values of lumped components inside the one-stage RLC equalizer circuit. Multiple stages may be adopted, but the simulation result does not show any further enhancement on the eye quality. RL equalizer circuit is also applicable when the impedance matching situation is not a critical concern. Good agreements between the simulations and measurements have verified the effectiveness of this compensation method.
As for the design of high-impedance reflection gain, a systematic design methodology is proposed to resolve the optimal inductance or length of high-impedance line inserted into the conventional matched termination for the finest compensation efficiency. A simple expression is derived to give the optimal inductance design, while the optimal length of high-impedance line can be estimated using a quasi-static equivalent circuit followed by a correction factor. In addition, two help graphs are constructed to evaluate the enhancement of maximally usable length for the PCB-scale microstrip transmission line with compensation. Some experiments are also performed to validate the proposed concept.
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Lai, Yen-Cheng, and 賴彥成. "Fast Eye Diagram Algorithm and FIR Compensation Design for General Transmission Line Systems." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/26213525579686437610.
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碩士<br>臺灣大學<br>電信工程學研究所<br>98<br>In the modern design of high-speed digital system, eye diagram is a beneficial metric of intuitively and quickly assessing the quality of digital signals through various interconnection structures. The tranditional way of eye-diagram acquisition by simulating the response of a long pseudo-random bit sequence (PRBS) consumes large amounts of time and memory and cannot obtain the worst-case eye diagram. In this thesis, a fast algorithm is first purposed to predict the worst-case eye diagram for the transmission line system with an arbitrary step response. Based on the property that the output waveform of a channel can be generated by time-shifted step responses multiplying corresponding transition polarities, eye-diagram waveform at a certain window time is formed by UI-separated voltage samples on the step response. With a proper manipulation of time-shifting, flipping and superposition, peak and valley values of these voltage samples can carry all ISI effects to the same time, producing a worst-case eye voltage. From the positions and transition polarities of voltage samples that are used, a substitution of PRBS, the input bit pattern is translated for simulating the worst-case eye diagram. Besides, this algorithm can be extended to handle signals with asymmetric rise/fall time if introducing two step responses that describe positive and negative transitions respectively. Furthermore, a probability model of that an n-bit specific pattern appears in an m-bit PRBS is developed to explain why it is not likely for a PRBS to carry the worst-case bit pattern that generates the worst-case eye diagram.
The second part of the thesis focuses on the compensation design for the imperfect effects of transmission line loss and multiple reflections due to mismatch loads by adding a pre-emphasis circuit at the transmitter side. Owing to the benefits of stability, linear phase, less area and low power comsumption, the finite impulse response (FIR) filter is adopted as the pre-emphasis circuit. With the aid of fast eye diagram algorithm, the optimal set of the tap coefficients can be extracted by applying the time domain optimization that is to maximize the reduction of voltage noise of the eye diagram within a range of window time. The simulation and experimental results of transmission line systems with matched, underdriven and overdriven impedance schemes that actually employ the pre-emphasis compensation technique are shown that the eye diagrams are reopened even if the compensated frequency responses do not become flat.
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Huang, Pei-Wei, and 黃培瑋. "Analysis and Mitigation of Plating Stub Effect on Transmission Waveform and Eye Diagram." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/ms7x5v.
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碩士<br>中原大學<br>電子工程研究所<br>102<br>Plating stubs inevitably form in the manufactured processes for Ball Grid Array (BGA) packages. This work investigates how the plating stub affects the time-domain transmission (TDT) waveform and eye diagram. A scheme for mitigating the effect of the plating stub is also proposed. The effects of time-domain reflection noise generated by the plating stub on the TDT waveform are precisely studied by using a lattice diagram. Simple and approximate formulas are developed to determine whether the eye diagram crosses the eye mask. Based on this determination, the maximum length of the plating stub can be estimated. A low-cost scheme, scheme using a narrow stub trace with a slotted ground plane is proposed for mitigating the effect of the plating stub. Two design steps for ensuring that the eye diagram does not cross the eye mask are proposed. They are estimation of the maximum plating stub length and implementation of the scheme for mitigating the effect of the stub. The TDT waveform, insertion loss and eye diagram can be significantly improved by applying the mitigation scheme. Finally, the proposed analyses are validated by favorable comparisons between the simulation and measured results in the time and frequency domains.
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Chao, Yen-Lin, and 趙晏麟. "MEASUREMENT TECHNIQUE OF EYE DIAGRAM FOR CONNECTORS USED IN HIGH-SPEED DIGITAL TRANSMISSION." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/18732644194120086765.
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碩士<br>大同大學<br>通訊工程研究所<br>97<br>In this thesis, we use eye diagram to analyze the high speed signal, and introduce how to analyze the signal quality through the eye diagram. We design two different test fixtures to show the effect for the connector analysis. We also establish the SPICE (Simulation Program with Integrated Circuit Emphasis) model for Z-PACK HM-Zd connectors, and introduce how to extract the equivalent circuit of high speed connector by TDR (Time Domain Reflectometry). Importing the SPICE model to the package software Microwave Oiffice and feeding a pseudo random bits train to the SPICE model to do the eye diagram simulation. We also feeding a pseudo random bits train that generated by Tektronix DG2040 data generator to the test fixture and compare the simulation result to the physical measurement.
After confirming the simulation of the equivalent model with the measurements, we cut off the portion of test fixture from the whole equivalent model; we can obtain the equivalent model of Z-PACK HM-Zd connectors.
Finally, we use two different test fixtures for equivalent models of Z-PACK HM-Zd connectors. The confirmation of the equivalent model using package software Microwave Office show the test fixtures have a very great influence to analyze the high speed connectors, and our proposed method is applicable.
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Chang, Wei-Ju, and 張瑋儒. "Eye Diagram Analysis and Equalization Design of Pulse Amplitude Modulation in High Speed SerDes." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/5vyj63.
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碩士<br>國立臺灣大學<br>電信工程學研究所<br>106<br>The pursuit of larger data volume and higher switching speed in networking has emerges the 4-level pulse-amplitude modulation (PAM4) for the SerDes systems. In this thesis, the worst-case bits pattern method is proposed to derive the worst-case eye diagram for PAM4 without large PRBS simulation. Then, an optimization algorithm is established to search for the best finite impulse response (FIR) filter coefficients based on PAM4 extended peak distortion analysis (PDA) to improve PAM4 eye diagram efficiently. Finally, it is applied to calculate the suitable layout region for NRZ and PAM4 respectively, thereby addressing the preference zone for NRZ and PAM4.
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Lai, Qun-Yu, and 賴群宇. "Applying the Venn Diagram Based Text-Mining and Eye-Tracking Technology to Advertising Recommendation." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/30730996875982814103.
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碩士<br>國立暨南國際大學<br>資訊管理學系<br>104<br>While online advertising usually incorporates eye-catching images or pop-ups to attract user attention, it is less likely to mine data generated by user interaction with the system when browsing. This study attempts to utilize natural human reading behavior and determine which contents user attention is focused on to investigate users’ underlying preferences and recommend targeted advertising for said users. The experiment utilizes eye tracking technology combined with Venn diagram concepts to propose a data mining method. Using Venn diagram concepts, words in different sets are assigned weighted values and are transformed into units that can be used for calculation. This study first verified the effectiveness of the method of categorization, and then analyzed its predictive ability via experimentation. Results show that, in terms of advertising recommendation predictivity, the system exceeds the value of the threshold for non-random probability.
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Chiu, Shih-Heng, and 邱士恆. "Adaptive Decision Point Control and Eye diagram Reconstruction applied to High Speed Wire Communication." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/65478675629889022214.
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碩士<br>國立臺灣大學<br>電信工程學研究所<br>102<br>In common Clock and Data Recovery circuits, we usually put the decision point(sampling phase and voltage threshold) at the center of Eye diagram when we concern about the jitter. But in real world, the shape of signal would be effected by noise、dispersion and ISI…etc, which makes the Eye diagram not ideal and symmetric, and the decision point is not at the center of Eye diagram anymore.
To reduce the BER, we have to adjust the decision point to ideal place. Therefore, we need a mechanism to adjust the decision point automatically, it can adjust the sampling phase and voltage threshold according to different condition of distortion. We called it “Adaptive Decision Point Control”.
In this thesis, we proposed a theorem based architecture of ADPC applied to high speed wire communication. After get the synchronous amplitude histogram, we can find the ideal sampling phase and voltage threshold by using Nearest Gaussian algorithm, and we can also improve the BER.
In this thesis, we also proposed an architecture of Synchronous Eye diagram Reconstruction. By transfer the histogram of every phase to correspond one dimensional density, we can reconstruct the Eye diagram. The resolution of the Eye diagram is 256(phase)X256(voltage level). The sample number of Eye diagram is 256(phase)X512(sample number of a histogram).
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Chen, Mu-Chi, and 陳睦棨. "Level Strength Effect on Eye Diagram and Electromagnetic Interference for High Definition Multimedia Interface Systems." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/30053387838599447759.
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碩士<br>淡江大學<br>電機工程學系碩士在職專班<br>104<br>HDMI (high-definition multimedia interface) is a digital interface to transfer image and sounds. It is a common output device for the development technology in recent years. However, EMI (Electromagnetic Interference) is an important issue in such high speed transmission and a lot of problems need to be resolved. Some techniques without extra cost for reducing EMI issues deteriorate eye diagram and some techniques increase the cost by placing numerous shielding on metal chassis.
In this thesis, we will focus on the research for note book using Intel processer with HDMI output. It provides a few modification parameters to adjust the signal strength in the Basic Input/Output System (BIOS). It is found that, without increasing the cost and changing the layout, the eye diagram and EMI could be compromised by our proposed techniques for adjusting the level output of BIOS as the following:
1. To satisfy the criteria for eye diagram, the level strength can be set as the default value 1000mV0.0dB or reduce to 800mV0.0dB.
2. To satisfy the criteria for EMI, the level strength can be set as 800mV0.0dB or 600mV0.0dB.
3. To satisfy the criteria for both eye diagram and EMI, the level strength must be set as 800mV0.0dB.
Finally, compared to the conventional techniques, our proposed techniques can improve both eye diagram and EMI without increasing the cost and changing the layout.
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Silva, Diogo Miguel Magalhães Góis da. "Estrutura de processos logísticos na gestão de armazém: o caso do WMS Eye Peak." Master's thesis, 2019. http://hdl.handle.net/1822/61798.
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Dissertação de mestrado em Engenharia Industrial<br>Atualmente, os warehouse management systems (WMS), apesar da sua grande complexidade, estão cada vez mais presentes nas organizações. Estes sistemas têm vindo a ser desenvolvidos para serem moldáveis às especificações e necessidades de cada organização e para que, assim, as empresas retirem o máximo proveito das suas funcionalidades.
Além das características técnicas do software é importante ter em consideração o seu contexto e onde é que elas se encontram inseridas, isto porque, os mercados são, atualmente, cada vez mais exigentes, globais e voláteis, derivado da quantidade de informação disponível e do constante desenvolvimento de tecnologias que potenciam a automatização no seio empresarial.
Neste trabalho pretende-se descobrir como é possível alavancar o WMS Eye Peak para o sucesso, utilizando uma metodologia de estudo de caso recorrendo ao uso da aplicação, observação, análise documental e conversas informais. O estudo centra-se nas funcionalidades da versão 5.0 do software desenvolvido pela empresa Primavera BSS, procedendo-se à realização de diagramas SIPOC dos diversos processos logísticos, que serviram para mapear e dar origem a uma análise funcional do sistema em estudo.
Foi, ainda, realizado um benchmarking com os diversos concorrentes para entender o posicionamento do software no mercado global, onde se chegou à conclusão que a escassez de oferta e interligação a nível de tecnologias emergentes do Eye Peak, comparativamente com os seus homónimos do mercado internacional, poderá ser um dos maiores problemas atuais. Contudo, após a elaboração dos diagramas SIPOC dos processos logísticos na gestão de armazém, ficou claro que, além de as equipas da Primavera BSS terem um recurso útil para futuras ações de implementação, o sistema Eye Peak também consegue realizar os processos básicos gerais numa gestão de armazéns.<br>Currently, warehouse management systems (WMS), despite their complexity, have experienced an increasingly presence in organizations. These systems have been developed to be customized to the specifications and needs of each organization, so that companies get the most out of their functionality.
In addition to the technical characteristics of the software, it is important to have in consideration their context and where they are inserted, because the markets are currently becoming more challenging, global and volatile, derived from the amount of information available and the constant development of technologies that boost, among other advantages, automation in the business world.
In this work is intended to find out how it is possible to leverage WMS Eye Peak for success, employing a case study methodology using the application, observation, document analysis and informal conversations. The study focuses in the version 5.0 functionalities of software, developed by the company Primavera BSS. SIPOC diagrams of the varied logistic processes were carried out, which served to map and give rise to a functional analysis of the system under study.
A benchmarking process was also carried out with the various competitors to understand the positioning of software in the global market, where it was concluded that the lack of interconnection of emerging technologies, in comparison with their international market competitors, can be one of the biggest problems to report nowadays. However, after producing the logistic processes in warehouse management, it became clear that in addition to the implementation teams of Primavera BSS have a useful resource for future actions, the Eye Peak system can also perform the basic general processes in what concerns about warehouse management.
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Tseng, Wenyen, and 曾文彥. "An Eye-Tracking Study of Different Metacognitive-Ability Nursing Student’s Recognition Processes While Viewing Diagram and Text Representations." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/852tw2.
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博士<br>國立彰化師範大學<br>科學教育研究所<br>107<br>Nursing students need to view and judge the patient's diagnostic information both in textbook learning and in future clinical work. These information, such as vital sign diagrams, are usally missing in the textbooks. Metacognition is a critical element that correlates to the learning process. Utilizing metacognition, nursing students ought to be able to systematically analyze complex situations in a classroom and to integrate the knowledge into their clinical practice. Nevertheless, there is a lack of research on metacognition in nursing education. There are two study in this research.The first study aimed to develop a Nursing Metacognition Scale of junior college students in Taiwan in order to easily and quickly understand nursing students’ metacognition ability for learning and practicing. The purpose of the second study was to use two different diagram and text representations, “comprehensive diagram and text representations” inluding traditional fever type texts and diagrams in the textbook plus vital sign and “traditional diagram and text representations” with traditional fever type texts and diagrams in the textbook only, to explore recognition processes of different metacognitive-ability nursing students.
In first study, using a survey method, a total of 854 valid samples were collected from four junior colleges. Exploratory and confirmatory factor analyses were performed to determine the best factor structure to represent the Nursing Metacognition Scale. The exploratory factor analysis resulted in 33 items and six factors, namely “Declarative Knowledge,” “Procedural and Conditional Knowledge,” “Planning,” “Information Management Strategies,” “Debugging Strategies,” and “Monitoring and Evaluation.” The Cronbach’s α was .939 for the full scale and .706 ~ .896 for the six subscales. The results of the confirmatory factor analysis verified that the Nursing Metacognition Scale had a good fit. The findings support that the Nursing Metacognition Scale is an appropriate tool for measuring nursing students’ metacognitive ability, and can be used for learning and teaching in nursing education.
In second study, the study recruited 83 nursing students from junior colleges in Taiwan to participate and the study included three phases. Firstly, participants were asked to complete prior knowledge test and Nursing Metacognition Scale for nursing students. Secondly, they viewed the diagram and text representations on the computer screen while eye movement behaviors were collected by an eye tracker. In the last phase, each participant was asked to complete judgment of learning, confidence judgment, a learning performance test and interview(strategies). The results revealed that high metacognitive-ability participants spent longer mean fixation duration and total fixation durations on the text of comprehensive diagram and text representations, and more inter-scanning counts between traditional fever diagrams and vital sign diagrams in comprehensive diagram and text representations. The qualitative data analysis of the interviews also displayed that high metacognitive-ability students were text-directed viewer on the comprehensive diagram and text representations and compared between traditional fever diagrams and vital sign diagrams. They performed better in learning performance because they were more efficient in cognitive processing to pay attention on text and to integrate information between traditional fever diagrams and vital sign diagrams. Metacognition was significantly related to eye movement and learning performance. This study provided evidence that participants with different levels of metacognition had different eye-movement behaviors, strategies and learning performance while viewing comprehensive diagram and text representations. Future studies may explore the students’ visualization patterns in viewing learning materials for students with different levels of metacognitive-ability.
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Yeh, Chi-Lou, and 葉啟樓. "Influence and Mitigation of Longest Differential Via Stubs on Transmission Waveform and Eye Diagram in a Thick Multilayered PCB." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/u6ez2m.
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碩士<br>中原大學<br>通訊工程碩士學位學程<br>102<br>This study investigates how the longest differential via stubs in a thick multilayered printed circuit board (PCB) affect the time-domain transmission (TDT) waveform and eye diagram. A reduction scheme is also proposed to mitigate the influence of the longest differential via stubs. The manner in which the time-domain reflection noise that is generated by the longest differential via stubs affects the TDT waveform is then investigated using a lattice diagram. Formulas for step voltages on the TDT waveform are derived by analyzing the lattice diagram. Next, the effects of parameters related to the longest differential via stubs on the TDT waveform are analyzed. A high-impedance difference scheme with/without additional air-via holes is proposed to mitigate the influence of the longest differential via stubs. This mitigation scheme significantly reduces the influence of the longest differential via stubs in a thick multilayered PCB not only in the time domain (TDT waveform and eye diagram) but also in the frequency domain (differential insertion loss |Sdd21|). Finally, favorable comparisons between the simulations and measurements in the time and frequency domains validate the proposed analyses and mitigation scheme.
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Lin, Jr-Hung, and 林志鴻. "Cognitive load and diagram comprehension in solving geometry problems: An integrative probe with eye tracker and hand writing devices." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/5fg4eq.
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博士<br>國立交通大學<br>教育研究所<br>102<br>Solving geometry problems which accompany with diagrams is considered a difficult task for most of students; even though the diagram is not complex. In this dissertation, the author aims to identify the sources of difficulties which solvers encountered in a geometry problem-solving scenario. To achieve the goal, four studies, which integrate self-report measures, eye movement, hand writing techniques, and statistical programs for analyzing eye movement data, were conducted to probe the cognitive processes during geometry problem-solving. In addition, the author developed programs that could help simultaneously trace eye movement as well as handwriting sequences.
In study one, the author attempted to identify the locus of difficulties in solving geometry problems based on the cognitive load theory. A series of problems of similar triangles were designed, and examined the validity for subsequent experiments. Five problems were selected and used to investigate source of difficulties in a geometry problem solving scenario.
The primary goal of study two was to evaluate whether the differences between the successful and unsuccessful solvers while solving the tasks with various difficulties could be observed with the help of an eye tracker. The eye tracking technique was used to observe the on-line processes of diagram comprehension for the successful versus unsuccessful problem solvers. The results indicated that eye movement is beneficial for observing the cognitive process in problem solving.
Anchoring on the findings derived from study one and study two, study three extensively investigated the usability and validity of applying eye tracker to explore the cognitive processes during the complete geometry problem solving (CPS) that involved simultaneously viewing (i.e., input) and writing (i.e., output) processes and the switching in between. The author examined whether the perceived difficulties and eye movements was correlated. In addition, the author searched for eye movement measures that are sensitive to the perceived difficulty of geometry problems. The results indicated that: (1) The perceived difficulties and eye movements were significantly correlated. (2) Unsuccessful solvers paid more attention on diagram comprehension than that in successful solvers, which was consistent to the finding of previous studies. (3) Three eye movement measures, including dwell time, fixation count, and run count significantly differed within specific areas of interest. The three eye movement measures were sensitive to the perceived difficulty when the problems were difficult.
The evidence from previous studies showed that diagram comprehension was one of the major sources of difficulties in solving geometry problems; therefore, study 4 sought to monitor and analyze the processes of diagram comprehension. The author examined potential explanations of problem solving difficulties by focusing on how the spatial relations of geometry diagram hindered the solvers from successfully solving the geometry problems. The most difficult problem (problem #5) was used as an example to conduct experiment. The author hypothesized that problem #5 was difficult because the two triangles were adjacent, which led to increase difficulties in recognizing diagrams that were required to correctly solve the problem. Another possible source of difficulties might be that the adjacent triangles could hinder solvers from identifying the length of specific sides. Therefore, separately presenting the adjacent triangles might help to solve the problem. This result suggested that separately presenting two triangles was helpful to reduce difficulties in integrating information in the diagram, though it might not be enough to successfully solving problems. The results partially supported the hypothesis that separately presented the pair of triangles was beneficial to diagram comprehension. Implications and suggestions for instructional design in mathematics education were discussed.
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Kemp, Jamie. "The Mind's Eye: Visualizing Encyclopedic Knowledge in the Later Middle Ages." Thesis, 2014. http://hdl.handle.net/1828/5773.
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This dissertation critiques and updates the theoretical frameworks for understanding encyclopedic and diagrammatic images as presented in the scholarship of Lucy Freeman Sandler, Barbara Maria Stafford, John Bender, and Michael Marrinan. It offers a new model for examining the cognitive role of images by studying an important medieval encyclopedia, On the Properties of Things, originally written in Latin by Bartholomaeus Anglicus in the thirteenth century.
Bartholomaeus’ text was the most popular encyclopedia of the later middle ages and four vernacular translations were produced and circulated between the fourteenth and sixteenth centuries. Significantly, the French translation of the compendium, coming out of the vernacularization movement of King Charles V but radiating out to other production centres, involved the design of an elaborate and novel illustrative program. The present project examines two exceptional fifteenth-century French copies of this encyclopedia (BnF fr. 9141 and BnF fr. 135/6), and interprets them in light of the shifting intellectual culture and evolving reading practices of late-medieval lay audiences.
The information-rich and highly aestheticized miniatures found in such encyclopedic manuscripts have traditionally been defined, by Sandler and others, as having an explanatory function and the capacity to elevate the content of the text through displays of material luxury. My model expands the significance of such images by highlighting their capacity to promote thought. I argue that images in didactic compendia can (i) encourage the reader to actively engage with the text through representations of aristocratic readers performing their understanding of the book socially, and (ii) facilitate visual thinking by aesthetically reflecting the structure of the encyclopedic text through the diagrammatic strategies of the collection, compression, and division of fragmented information. Though the images in my two manuscript case studies take distinct approaches to reader engagement and the mediation of knowledge, in both cases the power of these visualizations rests in the cognitive acts and range of mental associations they provoke. This dissertation demonstrates that epistemically-dense images, in addition to merely reflecting a text, could shape knowledge as it was being formed in the minds of active viewers, readers, writers, and artists, in an intellectually rich period in late-medieval France.<br>Graduate
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Sarvari, Siamak. "A 5Gb/s Speculative DFE for 2x Blind ADC-based Receivers in 65-nm CMOS." Thesis, 2010. http://hdl.handle.net/1807/29987.
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This thesis proposes a decision-feedback equalizer (DFE) scheme for blind ADC-based receivers to overcome the challenges introduced by blind sampling. It presents the design, simulation, and implementation of a 5Gb/s speculative DFE for a 2x blind ADC-based receiver. The complete receiver, including the ADC, the DFE, and a 2x blind clock and data recovery (CDR) circuit, is implemented in Fujitsu’s 65-nm CMOS process. Measurements of the fabricated test-chip confirm 5Gb/s data recovery with bit error rate (BER) less than 1e−12 in the presence of a test channel introducing 13.3dB of attenuation at the Nyquist frequency of 2.5GHz. The receiver tolerates 0.24UIpp of high-frequency sinusoidal jitter (SJ) in this case. Without the DFE, the BER exceeds 1e−8 even when no SJ is applied.
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Jian, Yu-Cin, and 簡郁芩. "Constructing and confirming a cognitive model of mechanical kinematic representation by recording eye movement during the reading of texts and diagrams." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/92728018646693341205.
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博士<br>國立臺灣師範大學<br>教育心理與輔導學系<br>101<br>The process of forming kinematic representations contributes to high-order cognitive behavior in humans. The purpose of this study was to construct a cognitive model of kinematic representations within a machine. Two experiments were designed to confirm this model. This model examined the function of text and diagrams for forming internal representations of configurations and kinematic information. Moreover, this model also examined how configuration and kinematic information interact with each other during reading. Readers’ eye movements and comprehension were monitored as they read a piece of text. Experiment 1 consisted of a two-stage procedure: readers first read diagrams and then read a text-and-diagram article about a flushing cistern. We investigated whether readers could construct kinematic representations of diagrams with or without arrows (arrow group versus non-arrow group). Results showed that step-by-step question scores were higher for the arrow group than for the non-arrow group after reading the mechanical diagrams; however, this difference disappeared when both groups read the text-and-diagram article and then revised the step-by-step questions. In addition, scores on troubleshooting questions were higher for the arrow group than for the non-arrow group after reading the text-and-diagram article. In our analysis of eye movements, the arrow group had shorter mean saccade lengths on the diagrams and had longer gaze durations toward the first diagram than the non-arrow group. As for the non-arrow group, the strategy they seemed to use was comparing the status between the two diagrams. Therefore, there were more saccades between the two diagrams for the non-arrow group than for the arrow group. Experiment 1 confirmed that diagrams with arrows conveyed kinematic information, but the kinematic information conveyed was not the same as what could be conveyed by words. In Experiment 2, we investigated whether readers have the ability to form internal representations of mechanical configurations described via written text. The relationship between a mechanical configuration and kinematic information was also of interest. Readers first read the mechanical configurations, which consisted of text or a diagram, and then read text describing kinematic information of the same system. Participants were assigned to one of three groups (configuration group, non-configuration group, or diagram group). Results showed that the configuration group had higher configuration tests scores than the non-configuration group. However, both groups made progress on the revised configuration tests after reading the kinematic text. In addition, the configuration test scores regarding local connective relations were higher for the configuration group than for the diagram group. However, on the global dimension of the same test, the diagram group did better than the configuration group. In our analysis of eye movements, the configuration group displayed shorter total fixation durations and rereading times of the kinematic text than did the non-configuration and diagram groups. Experiment 2 confirmed that readers were able to form a mental representation of the mechanical configuration described by written words. However, both text and diagrams have their advantages for describing configurations; the former’s advantage is on the level of describing local connective relations, while the latter’s advantage is on the level of global analogic relations within the mechanical system. Readers can utilize mechanical configurations to form kinematic information. Conversely, kinematic information could also be used to revise and adjust readers’ mental representations of mechanical configurations. In sum, the model of the current study has been confirmed through the results of two experiments. We discuss relevant empirical research and theoretical underpinnings as they pertain to the current study.
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Cepeda, Porras Gerardo. "Analyse, à l'aide d'oculomètres, de techniques de visualisation UML de patrons de conception pour la compréhension de programmes." Thèse, 2008. http://hdl.handle.net/1866/7232.
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Van, Tonder André. "Difficulties in the comprehension and interpretation of a selection of graph types and subject-specific graphs displayed by senior undergraduate biochemistry students in a South African university." Diss., 2010. http://hdl.handle.net/10500/4913.
Full textAbstract:
A carefully constructed set of 16 graphical tasks related to key biochemistry concepts was designed and administered to a group of 82 students in their final year of B.Sc. study.
The test mean score of 48,3% ( 12,1) was low and characterised by gender and ethnic differences. There was a moderate linear relationship between biochemistry grades obtained by the students over two years of study and their graphical literacy (r = 0,433). The majority of the students exhibited slope/height confusion and only seven students (8,5%) were able to answer the two items corresponding to Kimura‘s Level F, the most complex and difficult level of graphical literacy.
Eye tracking data gave valuable insights into different strategies used by students while interpreting graphs and is a valuable tool for assessing graphical literacy.
These findings confirmed other studies where researchers have found a widespread lack of graph comprehension among biological science students.<br>Institute of Science and Technology Education<br>M. Sc. (Science Education)