Browsing by Subject "Computer graphics"
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Item Adaptability of a graphic system processor to the graphical kernel system(Texas Tech University, 1988-08) Rajendiran, Kalar SNot availableItem An experimental investigation of a graphical interactive problem structuring aid for decision support systems(Texas Tech University, 1982-08) Pracht, William EverettThe ecology of field-feeding dabbling ducks wintering on the Southern High Plains of Texas was studied on a 50 km2 study area in Castro County, from September-March 1979-82. Ducks relied primarily on waste corn that averaged 364 j^ 12 kg/ha/field. Fields harvested at 14-21^ moisture lost more than twice the corn as fields harvested at 22-36^ moisture. Therefore, moisture content of corn at harvest provided a useful measure to predict initial waste. Waste cornfields underwent a variety of agricultural treatments that affected the abundance and availability of waste corn to waterfowl. Burning stubble maximized abundance and availability, whereas deep plowing reduced abundance by 975o. Disking and grazing reduced abundance by 77^ and 84-%, respectively. However, landowners tended to graze cattle on fields where initial waste was high and thus substantial amounts of waste corn remained when grazing was terminated. Manual salvage by migrant workers removed 58% of initial corn waste. Field-feeding waterfowl conducted 2 flights daily to cornfields near playa lakes where the birds concentrated. The average morning flight was initiated 52 j^ 1.5 min before sunrise and terminated in 23 _+ 1 .4 min. The average evening flight began 25 j^ 2.0 min after sunset and terminated in 37 j^ 4.2 min with duration increasing as the season progressed. Dabbling ducks fed longer and participated more in evening as compared to concurrent daily morning flights. Minimum temperatures were correlated negatively with duration of evening flights, but not morning flights. There was no correlation between the amount of waste corn in, or the condition of, a field selected by feeding ducks with duration or initiation of feeding flights. However, the amount of corn present was correlated negatively with duration of the evening flight. Snowfall was positively correlated with duration of evening flights, but not morning flights. Feeding flocks selected fields based on an abundance/availability hierarchy, apparently attempting to minimize foraging time. Eurned fields were preferred most when available, followed by disked fields, especially those containing >60 kg waste corn/ha. Field-feeding is an adaption to widespread agriculture, but also is a learned response to changes in wetland habitats.Item An experimental investigation of a graphical problem-structuring aid and nominal group technique for group decision support systems(Texas Tech University, 1986-05) Loy, Stephen LNot availableItem Animation in user interface design for decision making: a research framework and empirical analysis(Texas Tech University, 1995-12) Gonzalez, CleotildeAnimation is becoming an increasingly popular feature in user interfaces. Animation in infoiTnation displays is expected to influence decision making by facilitating and improving the human and computer interaction (HCI). Unfortunately, the use and effect of animated user interfaces for decision making are unknown. How should animated interfaces be designed to improve decision making performance? Answers to this question are crucial to design effective infoi-mation systems that support decision making. This research provides a new conceptual Animation User Interface Design (AUID) research framework for answering this question. In addition, this research empirically evaluates some of the AUID's propositions. The AUID research framework suggests a definition of animation in HCI, defines animation design goals, and presents an ai'chitecture to illustrate decision making with animated interfaces. This framework proposes that animation may support decision making if its design accounts for the task domain and structure; individual difference factors such as visual imaging abilities and experience; and characteristics of the animated interface such as images, alterations, transitions, timing, and interactivity. To explain possible decision making effects, the AUID framework focuses on theories of visual perception and cognition of successive displays. Several research hypotheses are derived from the propositions of the AUID framework. Primary hypotheses test the relative effects of images (realistic and abstract), transitions (gradual and abrupt), and interactivity (parallel and sequential) in two different decision making domains. Secondary hypotheses test the interaction between the animation interface design elements, the task domain, and the individual difference factors. A laboratory experiment was conducted to investigate these hypotheses. The results show that decision making performance in animated interfaces is highly contingent on the properties of the animation user interface such as image type, transition smoothness, and interactivity style as well as sensitive to the task domain. In sum, this reseai-ch suggests that a human information processing approach to design animated interfaces is a powerful one for supporting decision making. To be an effective decision support tool, animation must be smooth, simple, interactive, and explicitly account for the appropriateness of the user's mental model of the task.Item Automated Registration of Point Clouds with High Resolution Photographs and Rendering Under Novel Illumination Conditions(2010-12) Srisinroongruang, Rattasak; Sinzinger, Eric D.; Hoo, Karlene A.; Youn, Eunseog; Lakhani, GopalWith the increased computing power of modern technology, it has become feasible to digitally capture real world scenes and objects, preserving the scenes and objects indefinitely. Additionally, digitally capturing a scene provides the flexibility to re- visualize it under novel illumination conditions that may never occur at the scene’s real location. These two tools, scene capture and redisplay, are at the focal point of this proposal. Scene capture requires recording the spatial and intensity data of a real world scene. This is accomplished using LIDAR (a method of laser positioning) and pho- tographic cameras respectively. Once acquired, the data sets need to be registered together. This is the computation of a mathematical transform to that maps the photographic images onto the spatial data. Typically, this has been done using a significant amount of user interventation or requires the placement of distinguishing markers in the real scene. To remove these requirements and handle large data sets, the performed research submits methods to automatically compute the mathematical transforms between data sets with minimal manual intervention typically required in the current state of the art. This will be accomplished by posing the problem as an optimization problem with an objective function based upon a novel error metric. The redisplay portion of the research submits a novel rendering equation that is able to take cues from a photograph and realistically insert a synthetic object into the novel environment depicted in the photograph. This rendering equation allows the object to react realistically to the illumination conditions in the environment which may be substantially different from the environment conditions when the object or scene was captured.Item Computer-aided design use in interior design firms(Texas Tech University, 2004-05) Key, DeloresRapid changes in computer technology and the introduction of computer-aided design have contributed to the evolution of the interior design profession. Small firms are being challenged to compete with larger firms in order to survive in today's complex and diverse interior design profession. Understanding how interior design firms are using computer-aided design to meet the needs and expectations of their clients is important to the success of smaller firms. The sample for this study consisted of 322 professional members of the American Society of Interior Designers (ASID) and 179 professional members of the Intemational Interior Design Association (EDA) selected from the current membership directories provided by the national offices of ASID and BOA. The questionnaires were mailed to each subject and were designed to determine the statistical characteristics related to firm size, type of practice, education and CAD education background, computer usage, and expectations for entry-level employment. One hundred twenty-eight (39.8 %) of ASID and 78 (43.6 %) of EDA sample members returned questionnaires. The data indicated that interior design professionals graduated with a baccalaureate degree from FIDER accredited design programs, and are employed full time. A large number of ASID members graduated prior to the introduction of CAD to interior design programs. More than 52 % of the ASID sample have practiced interior design for more than 20 years, and 61.6 % of the EDA sample have practiced less than 20 years. Interior designers in both ASID and EDA expect entry-level employees to have a maximum level of CAD training and prefer to hire graduates with CAD training even if they do not use CAD. AutoCAD software is used by most designers in this study, and CAD software programs are used primarily for design preliminaries and construction drawings. Study results indicate that firm size affects gross income, but primarily for ASID study participants whose firms have 5 or less employees. Most firms in this study reported grossing more than $1,000,000; however, this is not true of firms with 1 to 5 employees. Firm size also appears to affect scope of work. Most interior design professionals, whose firms consist of from 1 to 5 employees, are residential designers. In addition study results indicate that as staff size decreases the percentage of employees who use CAD decreases and the scope of work also decreases. Most interior design professionals who participated in this study practice in firms with 1 to 5 employees. Data compiled from this study adds to the body of knowledge regarding computer aided design use in interior design firms and affirms the importance of CAD in the interior design profession. Additionally study results illustrate the importance of continuing to incorporate advanced computer-aided design into all phases of university interior design programs in order to prepare graduates to successfully enter the interior design profession. The information from this study may provide small firms with 1-5 employees to with information necessary to compete with larger firms. The information resulting from this study may also encourage the Foundation for Interior Design Research (FIDER) to consider including advanced CAD processes, such as 3D modeling and animations, as a additions to the existing levels of computer competencies required for accreditation. Study results may also affect university administrators' willingness to provide additional funding that may result in the development and implementation of university interior design programs that include advanced level CAD instruction in all upper-level interior design studio courses.Item Design and implementation of an extended relational database model(Texas Tech University, 1983-12) Mohamed, ZiauddinAn experimental implementation of an extended relational database model is described. Observations about the performance of the model are made, and some possible modifications are suggested. The extended model has been designed to make the conventional Relational model more suitable for engineering applications. Its principal feature is that it allows the static properties of graphical entities to be modeled more easily and directly.Item Developing strategies to evaluate the effective use of electronic presentation software in communication education(2003) Earnest, William James; Knapp, Mark L.Item Efficient drawing of partially oriented planar graphs with application to the circuit layout problem(Texas Tech University, 1985-05) Hanna, James ArthurNot availableItem Item Graphical simulation software for the tool path within an integrated CAD/CAM/CNC environment(Texas Tech University, 1995-12) Chen, ShanshanNot availableItem Haptic rendering of volumetric soft-bodied objects(Texas Tech University, 1998-08) Burgin, Jonathan RonaldThe interfacing of force-feedback devices to computers adds touchability in computer interactions, called computer haptics. Computer haptics has two components (1) collision detection of virtual objects with the haptic interface device and (2) determining and displaying appropriate force feedback to the user via the haptic interface device. This is a new field, with most of the original work done in the fields of mechanical engineering and the biophysical sciences. As such, the computing model that incorporates haptics was, until recently, a secondary concern. Most of the data structures and algorithms applied to haptic rendering have been adopted from non-pliable surface-based graphic systems, which is not always appropriate because of the different characteristics required to render haptic systems. Two new algorithms are currently available that can be applied to haptics to improve the collision detection and force-feedback generation of computer haptics. Currently, there are two basic methods available: (1) The occupancy-map algorithm (OMA), which is used for fast collision detection with solid non-deformable convex virtual objects, (2) The chainmail algorithm (CMA) used for calculating the behavior of 2D (surface) convex objects. The work we have done uses advanced computer modeling and coding techniques or implementing 1) haptic rendering of 3D volumetric objects using OMA for collision detection and 2) CMA for the generation of the real-time force feedback. Comparative analysis of this technique for haptic rendering versus more traditional methods has been provided. This work has enhanced the previous versions of this technique and has shown the viability and advantages of this new haptic rendering paradigm. These algorithms were implemented using the PHANToM haptic device from Sensible Technologies. This is a six-degree of freedom force feedback device used with many haptic displays. Graphics were implemented using the version of OpenGL provided with the Windows NT operating system.Item High capacity data hiding system using BPCS steganography(Texas Tech University, 2003-12) Srinivasan, YeshwanthNot availableItem High quality, high performance rendering using shadow ray acceleration and aggressive micropolygon tessellation rates(2011-05) Djeu, Peter; Fussell, Donald S., 1951-; Mark, William R.; Pingali, Keshav; Shirley, PeterRendering in computer graphics is the process of converting a three dimensional scene description into a two dimensional image. In this work we focus on high quality rendering, which has numerous applications in entertainment and visualization. Many films today are created either entirely or in concert with computationally generated imagery and serve as a vivid example of the benefits of high quality rendering. This dissertation consists of two parts, each presenting novel work in the field of high quality, high performance rendering. The first part proposes the use of volumetric occluders, or a collection of axis-aligned boxes placed within a polygonal model, to accelerate the rendering of shadows cast by the model while producing images identical to the unaccelerated baseline. We show that our approach performs well on single object scenes and extend our approach for use with scenes from a professional open source movie. Although the technique has not yet proven itself on these multi-object scenes, we identify the scene characteristics which are hampering the approach and show that in some cases it is still possible to achieve an improvement in performance. The second part of the dissertation presents a new way to determine micropolygon tessellation rate within a Reyes style renderer. Our new scheme, called final approach tessellation, evaluates the tessellation rate close to a Reyes surface rather than upon entry into its bounding box. Our determination of the tessellation rate is more aggressive than previous approaches, producing a more compact tessellation which in turn is faster to compute and requires less memory. Our evaluation shows that although final approach tessellation is promising in theory, it ultimately fails to improve performance on actual test scenes.Item Implementation of a data manager for computer graphics(Texas Tech University, 1985-05) Lahiri, SubhenduThe Generalization/Aggregation data model is an enhancement of the relational data model. It shows considerable promise for engineering applications because it allows abstract items to be stored in relational databases. However, the G/A model is only a data model. It cannot be used in database applications unless a data language exists to manipulate data items with that model. A database algebra for the G/A model is being developed at Texas Tech. This thesis describes the implementation of a data management system containing this algebra.Item Interpreter for the SPC-12 General Automation Computer(Texas Tech University, 1971-08) Armstrong, Walter PatrickNot availableItem A memory profiler for 3D graphics application using ninary instrumentation(2011-05) Deo, Mrinal; Fussell, Donald S., 1951-; Erez, MattanThis report describes the architecture and implementation of a memory profiler for 3D graphics applications. The memory profiling is done for parts of the program which runs on the graphics processor and is responsible for rendering the image. The shaders are parsed and every memory instruction is instrumented with additional instruction for profiling. The results are then transferred from the video memory to CPU memory. Profiling is done for a frame and completes in less than three minutes. The report also describes various analyses that can be done using the results obtained from this profiler. The report discusses the design of an analytical cache model that can be used to identify candidate memory buffers suitable for caching among all the buffers used by an application. The profiler can segregate results for reads and writes separately, can handle all formats of texture access instructions and predicated instructions.Item Multiresolution techniques on a parallel multidisplay multiresolution image compositing system(2001-12) Blanke, William John, 1972-; Bajaj, ChandrajitItem Post-demolition preservation: reclaiming lost architecture(Texas Tech University, 1998-12) Elwood, Kenneth LarryUntil now, the method used for historical documentation of lost architecture has primarily been achieved through the use of static two-dimensional media (photographs and drawings), which encompass separate images that can be tangentiaUy grouped. Thus, we rely upon the viewer's ability to effectively cognate the relationships of three-dimensional form and space imagery when trying to understand the bmlding as one complete whole. However, this methodology discounts the visual experience endemic in three-dimensional form and space because one cannot move through and around it, as we do in real life. Computer representations can be utilized to assist viewers in better understanding the visual experience of lost architectural form and space elements when taking advantage of threedimensional modeling and animation tools. Computer representation, as a post-demolition historical documentation methodology, will allow us to reclaim a greater visual understanding of lost architectural form and space elements not previously archived in such a process and form. The methodology utilizes the computer to create an animated, photorealistic, three-dimensional model, which is recorded onto a video medium. It wkl also allow us to cater to multiple viewers through the medium's accessibility, transportability, and cost.Item Post-demolition preservation: reclaiming lost architecture(Texas Tech University, 1998-12) Elwood, Kenneth LarryUntil now, the method used for historical documentation of lost architecture has primarily been achieved through the use of static two-dimensional media (photographs and drawings), which encompass separate images that can be tangentially grouped. Thus, we rely upon the viewer's ability to effectively cognate the relationships of three-dimensional form and space imagery when trying to understand the building as one complete whole. However, this methodology discounts the visual experience endemic in three-dimensional form and space because one cannot move through and around it, as we do in real life. Computer representations can be utilized to assist viewers in better understanding the visual experience of lost architectural form and space elements when taking advantage of three dimensional modeling and animation tools. Computer representation, as a post-demolition historical documentation methodology, will allow us to reclaim a greater visual understanding of lost architectural form and space elements not previously archived in such a process and form. The methodology utilizes the computer to create an animated, photorealistic, three-dimensional model, which is recorded onto a video medium. It will also allow us to cater to multiple viewers through the medium's accessibility, transportability, and cost.