Focus+context map labeling with optimized clutter reduction

In recent years, small screen devices, such as cellular phones or Personal Digital Assistants (PDAs), enjoy phenomenal popularity. PDAs can be used to complement traditional computing systems to access personal multimedia information beyond the usage as digital organizers. However, due to the physical limitations accessing rich multimedia contents and diverse services using a single PDA is more difficult. Hence, the Situated Computing Framework (SCF) research project at Siemens Corporate Research (SCR) aims to develop a ubiquitous computing infrastructure that facilitates nomadic users to access rich multimedia contents using small screen devices. This paper describes a new distributed computing concept, the Small Screen/Composite Device (SS/CD) framework, which offers mobile users new classes of ubiquitous and mobile multimedia services without to limit the diversity and the richness of the provided services.

In this study we focused on the social representations of digital teaching among Higher Education agents, considering their reported experience (more or less diversified) and type of access (mobile devices or not, large-screen devices or small screen-devices). The context of the study was a public Higher Education institution in the North of Portugal in which the Moodle was adopted years-ago to support learning activities. The participants were 36 teachers (39% males, 61% females), aged between 25 and 55 years-old, and 144 freshmen students (20% males, 80% females), aged between 18 and 57 years-old, enrolled in different programs in the area of Health care. They answered to a questionnaire that consisted of: free association tasks around stimuli such as digital teaching and Moodle; a semantic differentiation scale on the attitudes towards Moodle; multiple choice questions about the levels of use and type of access to the platform; and demographic questions, including age and sex. A content-analysis of the qualitative data was conducted, using a macro developed in Excel. Words evoked by the participants were reduced to their most common form and phases rewritten to their common theme. Words and themes were then grouped under overarching categories. A descriptive analysis of the quantitative data was also performed. Results revealed that whereas for the teachers the semantic field of digital teaching consisted of the categories accessibility (47%), evolution (42%), and distance (39%); for the students it consisted of technology (97%), evolution (59%), and easiness (37%). The Moodle was seen as a kind of repository by the majority of the students (89%). Such image is shared by less than one half of teachers (36%) and it was more common among those who declared to use more functionalities of the learning management system (LMS). It is worth mentioning that almost one half of students associated the Moodle with knowledge (49%). Errors and the dependency on the Internet were pointed out as the main constrains of the LMS, while accessibility and easiness of use were the main advantages. With respect to access, the portable computer was the device most used by both teachers and students (90%). Desktops were used by more than 80% of teachers and by less than 20% of students, while the reverse picture was found in the access by mobile phone (around 20% of teachers and around 70% of students). This study provides interesting clues about the relation between the social position of the agents and their representations. The social representations seem to be more homogeneous among students than among teachers, suggesting that there is a relation with practices. The fact that the image of the Moodle as a repository is more present among the teachers who reported having used more functionalities of the Moodle is somewhat counter-intuitive and urges for more studies. It is also very suggestive that the agents use different anchors to represent digital teaching: distance in the case of the teachers and technology in the case of the students, though they converge in seeing it as a sign of evolution. Although mobile access seems to be more frequent among students, big screen devices are more used than small screen devices. These results do not support the idea of a screen-device gap among the participants, but should nevertheless open a discussion about what kind of affordances are being explored in digital teaching.

In recent years, small screen devices have seen widespread increase in their acceptance and use. Combining mobility with their increased technological advances many such devices can now be considered mobile information terminals. However, user interactions with small screen devices remain a challenge due to the inherent limited display capabilities. These challenges are particularly evident for tasks, such as information seeking. In this paper we assess the effectiveness of using hierarchical-query biased summaries as a means of supporting the results of an information search conducted on a small screen device, a PDA. We present the results of an experiment focused on measuring users’ perception of relevance of displayed documents, in the form of automatically generated summaries of increasing length, in response to a simulated submitted query. The aim is to study experimentally how users’ perception of relevance varies depending on the length of summary, in relation to the characteristics of the PDA interface on which the content is presented. Experimental results suggest that hierarchical query-biased summaries are useful and assist users in making relevance judgments.

Today, the average consumer is comfortable browsing a web site using a desktop, laptop or kiosk computer. However, this is changing a rapid rate as more and more consumers access the same web content using a small screen device such as a mobile phone or personal digital assistant (PDA). Regardless of the consumers’ expertise with the mobile device, the experience is becoming frustrating as they try to navigate their way through web content that has been designed for a large screen; a design that results in cumbersome layout, slow-loading images and ‘off-screen’ navigation points when viewed on a small screen device. The result is dissatisfaction on part of the consumer, and possible loss of revenue for an e-business enterprise. The main objective of this paper is to highlight several techniques and technologies that are currently available that can assist in displaying ‘user-friendly’ web pages regardless of the screen size of the device.

In this paper, we illustrate the use of space-time trade-offs for information presentation on small screens. We propose the use of Rapid Serial Visual Presentation (RSVP) to provide a rich set of navigational information for Web browsing. The principle of RSVP browsing is applied to the development of a Web browser for small screen devices, the RSVP browser. The results of an experiment in which Web browsing with the RSVP browser is compared with that of a typical WAP browser suggests that RSVP browsing may indeed offer alternative to other forms of Web browsing on small screen devices.

Small screen appliances, such as cellular phones or Personal Digital Assistants (PDAs), enjoy enormous popularity as is evidenced by the tremendous commercial success. One focus of the ubiquitous research community is the potential utility of this class of devices beyond that of a basic organizer or communication device. The pocket-sized requirement imposes constraints upon the computational power and user interface of these small screen devices. This paper describes the Composite Device Computing Environment (CDCE) that offers a framework for supporting nomadic users with small screen devices for the retrieval of rich contents and the access of diverse services. CDCE provides a communication network infrastructure for seeking, unifying and exploiting any surrounding devices as a means to overcome the small screen client constraints. This paper describes the architecture and reports the current status of the ongoing realization of CDCE.

Design of text entry on small screen devices, e.g. smartwatches, faces two related challenges: trading off a reasonably sized keyboard area against space to display the entered text and the concern over fat fingers. This paper investigates tap accuracy and revisits layered interfaces to explore a novel layered text entry method. A two part user study identifies preferred typing and reading tilt angles and then investigates variants of a tilting layered keyboard against a standard layout. We show good typing speed (29 wpm) and very high accuracy on the standard layout - contradicting fears of fat-fingers limiting watch text-entry. User feedback is positive towards tilting interaction and we identify ∼14° tilt as a comfortable typing angle. However, layering resulted in slightly slower and more erroneous entry. The paper contributes new data on tilt angles and key offsets for smartwatch text entry and supporting evidence for the suitability of QWERTY on smartwatches.

PurposeThe purpose of this paper is to carry out a survey in order to better understand the nature of handheld mobile computing use by academic library users and to determine whether there is a significant demand for using the library services with these small screen devices.Design/methodology/approachA survey is created to measure whether people want to access an OPAC with a small screen. Additionally, through open‐ended questions, the survey attempts to gain a broader understanding of handheld mobile computing's impact on, and implications for, the services provided by academic libraries.FindingsA total of 58.4 percent of respondents who own a web‐enabled handheld device indicate that they would use small screen devices, such as PDAs or web‐enabled cell phones to search a library OPAC.Originality/valueThe increasing prevalence of handheld mobile computing devices such as PDAs and web‐enabled cell phones warrants investigation as to its impact on libraries. This study examines an academic library user population and the potential demand for using the library's catalog with handheld mobile computing devices

Online graphics recognition has become the key problem for pen-based user interface on small screen devices, such as PDA and Tablet PC. In this paper, a novel constraint-based approach to online graphics recognition is proposed. The key idea of our approach is that when the user is drawing a graphic object, the system can extract the constraints between primitives and basic shapes from the object and use these constraints to retrieve similar graphic objects from the database at run time. The user can then choose the standard object from the ranked list of results to replace his sketches before he finishes drawing all strokes of the object. For this purpose, we summarize three types of primitives and several types of basic shapes as the basic components of a graphic object. We also define a set of constraints between primitives and basic shapes to represent their structural relations. The algorithms for online constraint extraction and graphics recognition are also presented. Experimental results show that our approach is efficient for online graphics recognition and effective for improving the user’s productivity.

A great deal of research has been done focusing on font, text size, and background colors for use with PowerPoint and on Web pages; but no research has been done to aid in the development of PowerPoint presentations for use on small screen devices such as the iPod.In this study, the researcher developed a PowerPoint that tested font size and clarity, text color against background, as well as clarity of images and graphs and found that much of what works in a quality PowerPoint presentation for computer screens does not work for small screens. This paper presents the result of this study and suggests some guidelines that can be used to create video podcasts that can be viewed in a variety of settings; thereby making the video podcast a useful extension of the classroom PowerPoint.

Semantic information is necessary for Semantic Web processing and is useful to Web adaptation services such as personalization of users' browsing activities on small screen devices. However, semantic information is always implicitly encoded in most existing HTML documents. This paper describes a page segmentation method to parse Web pages into rectangular segments containing some semantic information, namely blocks. Existing page segmentation techniques are mainly built on HTML DOM structure or purely vision based, not accurate enough either in visual presentation or in semantic sense. Our approach is automatic, and based on a refined typing system which tightly couples type analysis with indispensable visual cues to generate blocks into the tree structure, aiming to achieve high degree of coherence in both semantic and visual views. Experimental results show better accuracy and completeness of our method over existing ones.

This paper proposes a strict constructing approach for a reasonable membership function as objectively as possible. It is important to set a reasonable membership function to parameters for real-world decision making interactively and objectively. The main contribution of our proposed approach is to integrate a general continuous function derived from mathematical programming under a given probability density function based on real-world data into subjective interval estimation by a heuristic method. The interval estimation is to set intervals that a decision maker confidently judges whether an element is completely or never included in the given set. The main steps of our proposed approach are to solve the mathematical programming problem in terms of objectivity. It is hard to solve the problem with nonlinear function directly and efficiently. In this paper, the given nonlinear membership function is approximately transformed into a piecewise linear membership function, and the appropriate membership values are determined based on the strict optimal solution.

This thesis aims at developing efficient mathematical methods for solving hierarchical dynamic optimization problems. The main motivation is to model processes in nature, for which there is evidence to assume that they run optimally. We describe models of such processes by optimal control problems (called optimal control models (OCMs)). However, an OCM typically includes unknown parameters that cannot be derived entirely on a theoretical basis, which is in particular the case for the cost function. Therefore, we develop parameter estimation techniques to estimate the unknowns in an OCM from observation data of the process. Mathematically, this leads to a hierarchical dynamic optimization problem with a parameter estimation problem on the upper level and an optimal control problem on the lower level. We focus on multi-stage equality and inequality constrained optimal control problems based on nonlinear ordinary differential equations. The main goal of this thesis is to derive numerically efficient mathematical methods for solving hierarchical dynamic optimization problems, and to use these methods to estimate parameters in high-dimensional OCMs from real-world measurement data. We develop parameter-dependent OCMs for the gait of cerebral palsy patients and able-bodied subjects. The unknown parameters in the OCMs are then estimated from real-world motion capture data provided by the Heidelberg MotionLab of the Orthopedic University Clinic Heidelberg by using the mathematical methods developed within this work. The main novelties and contributions of this thesis to the field of hierarchical dynamic optimization are summarized herein. - We establish a novel mathematical method, a so-called direct all-at-once approach, for solving hierarchical dynamic optimization problems based on the direct multiple shooting method and first-order optimality conditions. - Furthermore, we propose an efficient numerical algorithm for large-scale hierarchical dynamic optimization problems, which fully exploits the structures inherited from both the hierarchical setting and the discretization. - Pontryagin's maximum principle is used to analyze solution properties of hierarchical dynamic optimization problems like second-order optimality conditions of the lower-level problem. - In addition, we propose and discuss alternative methods for hierarchical dynamic optimization that are based on derivative-free optimization and a bundle approach. These methods keep the hierarchical problem setting and do not reformulate the lower-level problem using first-order optimality conditions. - We establish a novel lifting method for regularizing mathematical programs with complementarity constraints, which is discussed and numerically investigated by means of a well-known collection of benchmark problems. - Proofs of regularity and convergence results for sequential quadratic programming methods applied to lifted mathematical programs with complementarity constraints are provided. - Efficient state-of-the-art implementations of all mathematical methods derived in this thesis, as well as a benchmark collection of hierarchical dynamic optimization problems are presented. - High-dimensional optimal control gait models for cerebral palsy patients and able-bodied subjects are developed. The mathematical methods derived in this thesis are used to estimate the unknown model parameters from real-world motion capture data provided by the Heidelberg MotionLab of the Orthopedic University Clinic Heidelberg. The theoretical and practical results presented in this thesis can be considered an initial motivating step towards answering open questions in current medical research in fields like treatment planning, classification of gaits, or the evaluation of surgeries by means of hierarchical dynamic optimization.

Spatial buffer analysis is one of the important and basic spatial operation functions of geographic information system. Studying 2D spatial buffer generation and analysis was more than the 3D spatial presently, thereby a novel 3D buffer generation algorithm based on vector was presented in this paper. 3D spatial solid is represented by B-Rep model and it's buffer is categorized into solid boundary buffer and solid interior, then construct the whole buffer by union operation on them. The boundary features of 3D spatial solid are classified into point feature, line features and face features. Usually, the statistical analysis is necessary after solid buffer generation. Thus, we proposed a new method which can quick judge whether the buffer affecting the surrounding objects based on collision detection theory. Finally, taking the surface and underground 3D space around University City region of Xianlin as the research area, a 3D buffer with complex geological environment and man-made buildings is created based on the new presented algorithm, and spatial statistical analysis is achieved based on the generated 3D buffer. The results show that the improved algorithm is efficient and practicable, especially the proposed 3D buffer generation algorithm based on vector is applicable for convex body and concave body comparing with current approaches.

ABSTRACTBandwidth is still a limiting factor for the Quality of Service (QoS) of mobile communication applications. In particular, for Voice over IP the QoS is not yet as good as for common, well-engineered, public-switched telephone networks. Multisensory communication has been identified as a possibility to moderate this limitation. One of the strengths of mobile video technology lies in its combination of visual and auditory modalities. However, one of the most salient features of mobile video applications is its small screen size. To test the potential of multimodal synergy for mobile devices, we assessed to what extent small screens affect multimodal synergy. This potential was assessed in an experiment with 54 participants, who conducted a standardised video-listening test for three talking-heads videos with a signal-to-noise ratio of –9 dB. The videos were presented on three different screen sizes, whilst keeping the video and auditory signals equal. Compared to a ground truth based on 359 participants, intelligibility was found to be significantly higher when using a large screen than when using a small screen. This indicates that mobile video technology has the potential for a significant multimodal synergy to which screen size is a substantial constraint. To optimally benefit from their multimodal potential, we offer suggestions on how to increase the effective screen size for small screen (e.g. mobile) devices and applications through elaborating the most relevant (visual) features. We conclude that knowledge about human sensory processing can alleviate the identified constraint and maximise the potential QoS of mobile video technology.