Tuner: a tool for designing and optimizing ion optical systems

Designing and optimizing ion optical systems is often a complex and difficult task, which requires the use of computational tools to iterate and converge towards the desired characteristics and performances of the system. Very often these tools are not well adapted for exploring the numerous degrees of freedom, rendering the process long and tedious, as well as somewhat random due to the very large number of local minima typically found when looking for a particular optical solution. This paper presents a novel approach to finding the desired solution of an optical system, by providing the user with an instant feedback of the effects of changing parameters. The process of finding an approximate solution by manually adjusting parameters is greatly facilitated, at which point the final tune can be calculated by minimization according to a number of constraints.Comment: 15 pages, 6 figures, to be published in Nuclear Instruments and Methods

Challenges in Developing Applications for Aging Populations

Elderly individuals can greatly benefit from the use of computer applications, which can assist in monitoring health conditions, staying in contact with friends and family, and even learning new things. However, developing accessible applications for an elderly user can be a daunting task for developers. Since the advent of the personal computer, the benefits and challenges of developing applications for older adults have been a hot topic of discussion. In this chapter, the authors discuss the various challenges developers who wish to create applications for the elderly computer user face, including age-related impairments, generational differences in computer use, and the hardware constraints mobile devices pose for application developers. Although these challenges are concerning, each can be overcome after being properly identified

Visualization of Accessible Multimedia Content in Web Pages

Multimedia content still presented on the web sites. The visualization of multimedia content by the users with disabilities, those that usually use screen readers, is extremely difficult. With the onset of the audio sequence of multimedia presentation it is difficult for users with visual impairs to listen the audio component of presentation and the audio version of the screen readers too, because the two audio streams cannot be controlled using only one volume control. Therefore, because of the difficulties to control the available audio streams and because of the difficulties to access the control buttons by people with disabilities, the multimedia content is often inaccessible for users with visual problems. More than this, the use of dynamic users’ interfaces is a critical problem because the screen-readers cannot detect the dynamics in content changes. The current paper presents some solutions for multimedia content production and distribution in distributed multimedia web presentations.Accessible multimedia content, Synchronized Accessible Media Interchange

DIVERSE: a Software Toolkit to Integrate Distributed Simulations with Heterogeneous Virtual Environments

We present DIVERSE (Device Independent Virtual Environments- Reconfigurable, Scalable, Extensible), which is a modular collection of complimentary software packages that we have developed to facilitate the creation of distributed operator-in-the-loop simulations. In DIVERSE we introduce a novel implementation of remote shared memory (distributed shared memory) that uses Internet Protocol (IP) networks. We also introduce a new method that automatically extends hardware drivers (not in the operating system kernel driver sense) into inter-process and Internet hardware services. Using DIVERSE, a program can display in a CAVE™, ImmersaDesk™, head mounted display (HMD), desktop or laptop without modification. We have developed a method of configuring user programs at run-time by loading dynamic shared objects (DSOs), in contrast to the more common practice of creating interpreted configuration languages. We find that by loading DSOs the development time, complexity and size of DIVERSE and DIVERSE user applications is significantly reduced. Configurations to support different I/O devices, device emulators, visual displays, and any component of a user application including interaction techniques, can be changed at run-time by loading different sets of DIVERSE DSOs. In addition, interpreted run-time configuration parsers have been implemented using DIVERSE DSOs; new ones can be created as needed. DIVERSE is free software, licensed under the terms of the GNU General Public License (GPL) and the GNU Lesser General Public License (LGPL) licenses. We describe the DIVERSE architecture and demonstrate how DIVERSE was used in the development of a specific application, an operator-in-the-loop Navy ship-board crane simulator, which runs unmodified on a desktop computer and/or in a CAVE with motion base motion queuing

Computational medical imaging for total knee arthroplasty using visualitzation toolkit

This project is presented as a Master Thesis in the field of Civil Engineering, Biomedical specialization. As the project of an Erasmus exchange student, this thesis has been under supervision both the Universite Livre de Bruxelles and the Universitat Politecnica de Catalunya. The purpose of this thesis to put in practice all the knowledges acquired during this Master in Industrial Engineering in UPC and to be a support for medical staff in total knee arthoplasty procedures. Prof. Emmanuel Thienpont has been working for years as orthopaedic surgeon at the Hospital Sant Luc, Brussels. His years of work and research have been mainly focused on Total Knee Arthroplasty or TKA. During one of the most important steps of this procedure, the orthopaedic surgeon has to cut the head of the femur following two perpendicular cutting planes. Nevertheless, the orientation of these planes are directly dependant of the femur constitution. This Master Thesis has been conceived in order to offer the surgeon a tool to determine the proper direction planes in a previous step before the surgical procedure. This project pretends to give the surgeon an openfree computational platform to access to patient geometrical and physiological information before involving the subject in any invasive procedure

Semantic multimedia remote display for mobile thin clients

Current remote display technologies for mobile thin clients convert practically all types of graphical content into sequences of images rendered by the client. Consequently, important information concerning the content semantics is lost. The present paper goes beyond this bottleneck by developing a semantic multimedia remote display. The principle consists of representing the graphical content as a real-time interactive multimedia scene graph. The underlying architecture features novel components for scene-graph creation and management, as well as for user interactivity handling. The experimental setup considers the Linux X windows system and BiFS/LASeR multimedia scene technologies on the server and client sides, respectively. The implemented solution was benchmarked against currently deployed solutions (VNC and Microsoft-RDP), by considering text editing and WWW browsing applications. The quantitative assessments demonstrate: (1) visual quality expressed by seven objective metrics, e.g., PSNR values between 30 and 42 dB or SSIM values larger than 0.9999; (2) downlink bandwidth gain factors ranging from 2 to 60; (3) real-time user event management expressed by network round-trip time reduction by factors of 4-6 and by uplink bandwidth gain factors from 3 to 10; (4) feasible CPU activity, larger than in the RDP case but reduced by a factor of 1.5 with respect to the VNC-HEXTILE

The svgl toolkit: enabling fast rendering of rich 2D graphics

As more and more powerful graphical processors be- come available on mainstream computers, it becomes possible to investigate the design of visually rich and fast interactive applications. In this article, we present S VGL , a graphical toolkit that enables programmers and design- ers of interactive applications to benefit from this power. The toolkit is based on a scene graph which is translated into an optimized display graph. After describing the algorithms used to display the scene, we show that the toolkit is two to fifty times faster than similar toolkits

Literature Survey on Interaction Techniques for Large Displays

When designing for large screen displays, designers are forced to deal with cursor tracking issues, interacting over distances, and space management issues. Because of the large visual angle of the user that the screen can cover, it may be hard for users to begin and complete search tasks for basic items such as cursors or icons. In addition, maneuvering over long distances and acquiring small targets understandably takes more time than the same interactions on normally sized screen systems. To deal with these issues, large display researchers have developed more and more unconventional devices, methods and widgets for interaction, and systems for space and task management. For tracking cursors there are techniques that deal with the size and shape of the cursor, as well as the “density” of the cursor. There are other techniques that help direct the attention of the user to the cursor. For target acquisition on large screens, many researchers saw fit to try to augment existing 2D GUI metaphors. They try to optimize Fitts’ law to accomplish this. Some techniques sought to enlarge targets while others sought to enlarge the cursor itself. Even other techniques developed ways of closing the distances on large screen displays. However, many researchers feel that existing 2D metaphors do not and will not work for large screens. They feel that the community should move to more unconventional devices and metaphors. These unconventional means include use of eye-tracking, laser-pointing, hand-tracking, two-handed touchscreen techniques, and other high-DOF devices. In the end, many of these developed techniques do provide effective means for interaction on large displays. However, we need to quantify the benefits of these methods and understand them better. The more we understand the advantages and disadvantages of these techniques, the easier it will be to employ them in working large screen systems. We also need to put into place a kind of interaction standard for these large screen systems. This could mean simply supporting desktop events such as pointing and clicking. It may also mean that we need to identify the needs of each domain that large screens are used for and tailor the interaction techniques for the domain