Sculpting

In desktop applications 3D input devices are mostly operated by the non-dominant hand to control 3D viewpoint navigation, while selection and geometry manipulations are handled by the dominant hand using the regular 2D mouse. This asymmetric bi-manual interface is an alternative to commonly used keyboard and mouse input, where the non-dominant hand assists the dominant hand with keystroke input to toggle modes. Our first study compared the keyboard and mouse interface to bi-manual interfaces using the 3D input devices SpaceTraveller and Globefish in a coarse spatial orientation task requiring egocentric and exocentric viewpoint navigation. The different interface configurations performed similarly with respect to task completion times, but the bi-manual techniques resulted in significantly less errors. This result is likely to be due to better workload balancing between the two hands allowing the user to focus on a single task for each hand. Our second study focused on a bi-manual 3D point selection task, which required the selection of small targets and good depth perception. The Globefish interface employing position control for rotations performed significantly better than the SpaceTraveller interface for this task.

This paper examines a new technique for the visualization of and the interaction with trees, objects frequently used to convey hierarchical relationships in biological data. Motivated by the quality of 2D tree interaction, we adapt the planar tree-of-life metaphor to a virtual, semi-immersive 3D environment. A 3D environment extends the utility of this metaphor by allowing the user to view an entire data set in a single screen. Interrogation of the tree is implemented using 3D input devices. This real-time interrogation of the tree itself provides a quick means by which to qualitatively analyse the hierarchical data. In this paper, we describe the techniques underlying the implementation of such an environment. We conclude by considering the utility of tree metaphors as a basis for the representation of highly dimensional data sets. Arbor3D (source code, a binary executable for SGI IRIX 6.4, Perl parsers, and sample Newick data files) are available via the Internet (http://xian.tamu.edu/Arbor3D/). Arbor3D can be displayed in "CAVE simulator" mode on an SGI workstation screen, or as an interactive virtual environment on a projection workbench. druths@rice.edu; echen@cs.rice.edu; leland@xian.tamu.edu

The most time-consuming part of character animation is 3D character posing. Posing using a mouse is a slow and tedious task that involves sequences of selecting on-screen control handles and manipulating the handles to adjust character parameters, such as joint rotations and end effector positions. Thus, various 3D user interfaces have been proposed to make animating easier, but they typically provide less accuracy. The proposed interface combines a mouse with the Leap Motion device to provide 3D input. A usability study showed that users preferred the Leap Motion over a mouse as a 3D gestural input device. The Leap Motion drastically decreased the number of required operations and the task completion time, especially for novice users.

Computer graphics hardware supporting real-time interactive 3D animation has the potential to support effective user interfaces by enabling virtual 3D workspaces. However, this potential requires development of viewpoint movement techniques that support rapid and controlled movement through workspaces. Rapid movement through large distances avoids wasted work time; controlled movement near target objects allows the user to examine and interact with objects in the workspace. Current techniques for viewpoint movement typically use high velocities to cover distances rapidly, but high velocities are hard to control near objects. This paper describes a new technique for targeted viewpoint movement that solves this problem. The key idea is to have the user indicate a point of interest (target) on a 3D object and use the distance to this target to move the viewpoint logarithmically, by moving the same relative percentage of distance to the target on every animation cycle. the result is rapid motion over distances that slows as the viewpoint approaches the target object. The technique can be used with 2D and multidimensional input devices. We also extend the technique to move objects in the workspace.

Converting from implicit surfaces into polygons and further optimization are a preprocessing step in rendering implicit surfaces for visualization and other uses. This paper describes a simple method for accurate polygonization of implicit surfaces with sharp features. First, an initial coarse mesh is generated by traditional Marching Cubes (MC) method, Then the mesh is used to approximate the implicit surface with simultaneous control of mesh vertex positions, regularity and normals. The refined mesh finally converges to a limit mesh which represents a high quality approximation of the implicit surface. To reconstruct small surface features, the optimization process combines with a curvature dependent mesh adaptive subdivision. For analyzing how close the refined mesh approximates the implicit surface, two error metrics are applied. One measures the deviations of the mesh vertices from the implicit surface, while the other measures the deviations of the mesh normals from the implicit surface.

Traditional lossless compression algorithms have some limitations to compress the data with special data structure. For fixed-length data compression of special industries, an algorithm was proposed based on Huffman coding and dictionary coding. The proposed algorithm uses an iterative approach to explore the repeated signature of the character strings. The compression dictionary was obtained and the data were compressed and transferred safely. Experiments prove that the proposed algorithm is more practical than the traditional LZW compression algorithm for the data compression with special structure. It has an improved compression ratio and a strong sense of confidentiality.

This paper outlines a system design and implementation of a 3D input device for graphical applications which uses real time hand tracking and gesture recognition to provide the user with an intuitive interface for tomorrow’s applications. Point Distribution Models (PDMs) have been shown to be successful at tracking deformable objects . This system demonstrates how these ‘smart snakes’ can be used in real time with a real world problem. The system is based upon Open Inventor1 and designed for use with Silicon Graphics Indy Workstations, but provisions have been make for the move to other platforms and applications. We demonstrate how PDMs provide the ideal feature vector for model classification. It is shown how computer vision can provide a low cost, intuitive interface that has few hardware constraints. We also give the reader an insight into the next generation of HCI and Multimedia, providing a 3D scene viewer and VRML browser based upon the handtracker. Further allowances have been made to facilitate the inclusion of the handtracker within third party Inventor applications. All source code, libraries and applications can be downloaded for free from the above web addresses. This paper demonstrates how computer vision and computer graphics can work together providing an interdisciplinary approach to problem solving.

For any knowledge-intensive undertaking (such as a stream or branch), it is critical to frame its birth and growth to understand where the discipline stands and what innovative endeavors lead to the creative accomplishments currently witnessed in its knowledge products. In this research paper, we describe the research and development of a knowledge platform called Interactive Knowledge and Modeling Techniques for Engineering Education Research. This research paper mainly describes with the explicit goal to provide a mechanism to better understand the emerging field of engineering education research and, more importantly, provide members of the engineering education research community with tools and infrastructure which allow them to understand the structure and networks of knowledge within the community at any given time. Using a theoretical model that combines ultra-large-scale data mining techniques, network mapping algorithms, and time-series analysis of knowledge product evolution, we attempt to characterize and provide insights into the topology of the networks and collaborations within engineering education research.

This article investigates the scheduling framework of the federated multitask learning (FMTL) problem with a hard-cooperation structure over wireless networks, in which the scheduling becomes more challenging due to the different convergence behaviors of different tasks. Based on the special model structure, we propose a dynamic user and task scheduling scheme with a block-wise incremental gradient aggregation algorithm, in which the neural network model is decomposed into a common feature-extraction module and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$M$ </tex-math></inline-formula> task-specific modules. Different block gradients with respect to different modules can be scheduled separately. We further propose a Lyapunov-drift-based scheduling scheme that minimizes the overall communication latency by utilizing both the instantaneous data importance and the channel state information. We prove that the proposed scheme can converge almost surely to a KKT solution of the training problem such that the data-distortion issue is resolved. Simulation results illustrate that the proposed scheme significantly reduces the communication latency compared to the state-of-the-art baseline schemes.

Chapter 64 - Exploiting Versions for On-line Data Warehouse Maintenance in MOLAP Servers

In this paper we propose the novel technique, On-line Contin-uous Ontological Evolution (OCOE) approach, which applies text mining to automate TCM (Traditional Chinese Medicine) telemedicine ontology evolution. The first step of the automation process is opening up a closed skeletal TCM ontology core (TCM onto-core) for continuous evolution and absorption of new scientific knowledge. The test-bed for the OCOE verification was the production TCM telemedicine system of the Nong's Company Limited; Nong's is a subsidiary of the PuraPharm Group in the Hong Kong SAR, which is dedicated to TCM telemedicine system development. At Nong's the skeletal TCM onto-core for clinical practice is closed (does not automatically evolve). When the OCOE is combined with the Nong's enterprise TCM onto-core it: i) invokes its text miner by default to search for new scientific findings over the open web incessantly; and ii) selectively prunes and stores useful new findings in special OCOE data structures. These data structures can be appended to the skeletal TCM onto-core logically to catalyze the evolution of the overall system TCM ontology, which is the logical combination: 'original skeletal TCM onto-core plus contents of the special OCOE data structures' The evolutionary process works on the contents of the OCOE data structures only and does not alter any skeletal TCM onto-core knowledge. This onto-core evolution approach is called the 'logical-knowledge-add-on' technique. OCOE deactivation will nullify the pointers and cut the association between the OCOE data structures and skeletal TCM onto-core, thus immediately reverting the clinical practice back to the original skeletal TCM onto-core basis.

Simulation of Robot Factories Using Robsim

To address the need for high-complexity low-cost interaction methods for mobile VR, we present a Cardboard Controller, supporting 6-degree-of-freedom target selection while being made of low-cost, highly accessible materials. We present two studies, one evaluating selection activation methods, and the other comparing performance and user experience of the Cardboard Controller using ray-casting and the virtual hand. Our Cardboard Controller has comparable throughput and task completion time to similar 3D input devices and can effectively support pointing and grabbing interactions, particularly when objects are within reach. We propose guidelines for designing low-cost interaction methods and input devices for mobile VR to encourage future research towards the democratization of VR.

Differentiated Instruction is an approach to teaching that considers the diverse learning needs, interests, and abilities of students. In contrast, the genre approach is a pedagogical method focused on teaching writing through the exploration and production of various genres. The objectives of this study are to investigate the implementation of a genre-based approach in teaching recount texts within a differentiated instruction framework, and to assess the impact of this approach on students’ learning outcomes and engagement. This research employs a qualitative method, which is a process of inquiry aimed at understanding human behaviors by creating complex, holistic pictures of the social and cultural contexts in which such behaviors occur. The data instruments include document analysis, observations, and interviews. Participants in this research consist of a teacher and students from SMP Al Azhar Pagelaran Malang. Data analysis follows an interactive model technique, which involves several stages: data reduction, data display, conclusion drawing, and triangulation. The result, teacher conducted an assessment to identify the students' needs. Subsequently, they implemented genre-based approach to make learning recount texts more engaging, allowing students to circulate and exchange information with different groups. From the interview data, it was evident that students enjoyed learning through differentiated instruction. With various learning styles accommodated, students felt confident in their understanding of the material presented in each lesson.

Tracking of multiple objects belongs to one of the fundamental tasks of computer vision. In this paper an improvement to the continuously adaptive mean shift tracking method is proposed. It consists in substitution of the probabilistic density function for the especially formed membership function. This makes possible design of tracking systems in terms of fuzzy logic. Additionally, a special data structure was developed to allow tracking of multiple objects at a time. It stores information on image regions which are active for tracking. By this it provides initial conditions for tracking in subsequent frames which also speeds up computations. The method was used and verified in an application of the road signs tracking in real time of 30 frames/s.