3,543 research outputs found
Finding information again using an individual’s web history
In a lifetime, an “average” person will visit approximately a million webpages. Sometimes a person finds they want to return to a given page at some future date but, having no recollection of where it was (URL, host, etc.) and so has to look for it again from scratch. This paper assesses how a person’s memory could be assisted by the presentation of a “map” of their web browsing activity. Three map organisation approaches were investigated: (i) time-based, (ii) place-based, and (iii) topic-based. Time-based organisation is the least suitable, because the temporal specificity of human memory is generally poor. Place-based approaches lack scalability, and are not helped by the fact that there is little repetition in the paths a person follows between places. Topic-based organisation is more promising, with topics derived from both the web content that is accessed and the search queries that are executed, which provide snapshots into a person’s cognitive processes by explicitly capturing the terminology of “what” they were looking for at that moment in time. In terms of presentation, a map that combines aspects of network connectivity with a space filling approach is likely to be most effective
Social Principles Underlying Traditional Inshore Fishery Management Systems in the Pacific Basin
Among fisheries management schemes, those based on sole ownership concepts have been relatively little studied. This concept has been most widely applied in the traditional fisheries management or sea tenure systems of the Pacific Basin, where, unlike the West, sole ownership resides in the community or other small social group. Information on Pacific Basin sea tenure systems remains largely anecdotal and unsynthesized. In a partial attempt to overcome that, this article defines and exemplifies six social principles common to many traditional systems of sea tenure in inshore fisheries management in the Pacific Basin, with reference to Oceanian islands, and based on an examination of the literature and supplementary field research. These principles are that: (1) sea rights depend on social status, (2) resource exploitation is governed by use rights, (3) resource territories are defined. (4) marine resources are controlled by traditional authorities, (5) conservation was traditionally widely practiced, and (6) sanctions and punishments are meted out for infringement of regulations. Most remaining systems are hybrids of traditional and modem components, with the latter becoming dominant. Interpretation of the literature without supplementary field verification is severely constrained by the use of the ''anthropological present'' tense.Environmental Economics and Policy, International Development, International Relations/Trade, Resource /Energy Economics and Policy,
Movement around real and virtual cluttered environments
Two experiments investigated participants’ ability to search for targets in a cluttered small-scale space. The first experiment was conducted in the real world with two field of view conditions (full vs. restricted), and participants found the task trivial to perform in both. The second experiment used the same search task but was conducted in a desktop virtual environment (VE), and investigated two movement interfaces and two visual scene conditions. Participants restricted to forward only movement performed the search task quicker and more efficiently (visiting fewer targets) than those who used an interface that allowed more flexible movement (forward, backward, left, right, and diagonal). Also, participants using a high fidelity visual scene performed the task significantly quicker and more efficiently than those who used a low fidelity scene. The performance differences between all the conditions decreased with practice, but the performance of the best VE group approached that of the real-world participants. These results indicate the importance of using high fidelity scenes in VEs, and suggest that the use of a simple control system is sufficient for maintaining ones spatial orientation during searching
Navigation: am I really lost or virtually there?
Data is presented from virtual environment (VE) navigation studies that used building- and chessboard-type layouts. Participants learned by repeated navigation, spending several hours in each environment. While some participants quickly learned to navigate efficiently, others remained almost totally disoriented. In the virtual buildings this disorientation was illustrated by mean direction estimate errors of approximately 90°, and in the chessboard VEs disorientation was highlighted by the large number of rooms that some participants visited. Part of the cause of disorientation, and generally slow spatial learning, lies in the difficulty participants had learning the paths they had followed through the VEs
Using string-matching to analyze hypertext navigation
A method of using string-matching to analyze hypertext navigation was developed, and evaluated using two weeks of website logfile data. The method is divided into phases that use: (i) exact string-matching to calculate subsequences of links that were repeated in different navigation sessions (common trails through the website), and then (ii) inexact matching to find other similar sessions (a community of users with a similar interest). The evaluation showed how subsequences could be used to understand the information pathways users chose to follow within a website, and that exact and inexact matching provided complementary ways of identifying information that may have been of interest to a whole community of users, but which was only found by a minority. This illustrates how string-matching could be used to improve the structure of hypertext collections
Using teleporting, awareness and multiple views to improve teamwork in collaborative virtual environments
Mobile Group Dynamics (MGDs) are a suite of techniques that help people work together in large-scale collaborative virtual environments (CVEs). The present paper describes the implementation and evaluation of three additional MGDs techniques (teleporting, awareness and multiple views) which, when combined, produced a 4 times increase in the amount that participants communicated in a CVE and also significantly increased the extent to which participants communicated over extended distances in the CVE. The MGDs were evaluated using an urban planning scenario using groups of either seven (teleporting + awareness) or eight (teleporting + awareness + multiple views) participants. The study has implications for CVE designers, because it provides quantitative and qualitative data about how teleporting, awareness and multiple views improve groupwork in CVEs. Categories and Subject Descriptors (according to ACM CCS): C.2.4 [Computer-Communication Networks]: Distributed Systems – Distributed applications; H.1.2 [Models and Principles]: User/Machine Systems – Human
factors; Software psychology; H.5.1 [Information Interfaces and Presentation]: Multimedia Information Systems
– Artificial, augmented and virtual realities; H.5.3 [Information Interfaces and Presentation]: Group and Organization Interfaces – Collaborative computing; Computer-supported cooperative work; Synchronous interaction; I.3.7[Computer Graphics]: Three Dimensional Graphics and Realism – Virtual Realit
Levels of control during a collaborative carrying task
Three experiments investigated the effect of implementing low-level aspects of motor control for a collaborative carrying task within a VE interface, leaving participants free to devote their cognitive resources to the higher-level components of the task. In the task, participants collaborated with an autonomous virtual human in an immersive virtual environment (VE) to carry an object along a predefined path. In experiment 1, participants took up to three times longer to perform the task with a conventional VE interface, in which they had to explicitly coordinate their hand and body movements, than with an interface that controlled the low-level tasks of grasping and holding onto the virtual object.
Experiments 2 and 3 extended the study to include the task of carrying an object along a path that contained obstacles to movement. By allowing participants' virtual arms to stretch slightly, the interface software was able to take over some aspects of obstacle avoidance (another low-level task), and this led to further significant reductions in the time that participants took to perform the carrying task. Improvements in performance also occurred when participants used a tethered viewpoint to control their movements because they could see their immediate surroundings in the VEs. This latter finding demonstrates the superiority of a tethered view perspective to a conventional, human'seye perspective for this type of task
Evaluating rules of interaction for object manipulation in cluttered virtual environments
A set of rules is presented for the design of interfaces that allow virtual objects to be manipulated in 3D virtual environments (VEs). The rules differ from other interaction techniques because they focus on the problems of manipulating objects in cluttered spaces rather than open spaces. Two experiments are described that were used to evaluate the effect of different interaction rules on participants' performance when they performed a task known as "the piano mover's problem." This task involved participants in moving a virtual human through parts of a virtual building while simultaneously manipulating a large virtual object that was held in the virtual human's hands, resembling the simulation of manual materials handling in a VE for ergonomic design. Throughout, participants viewed the VE on a large monitor, using an "over-the-shoulder" perspective. In the most cluttered VEs, the time that participants took to complete the task varied by up to 76% with different combinations of rules, thus indicating the need for flexible forms of interaction in such environments
Generating trails automatically, to aid navigation when you revisit an environment
A new method for generating trails from a person’s movement through a virtual environment (VE) is described. The method is entirely automatic (no user input is needed), and uses string-matching to identify similar sequences of movement and derive the person’s primary trail. The method was evaluated in a virtual building, and generated trails that substantially reduced the distance participants traveled when they searched for target objects in the building 5-8 weeks after a set of familiarization sessions. Only a modest amount of data (typically five traversals of the building) was required to generate trails that were both effective and stable, and the method was not affected by the order in which objects were visited. The trail generation method models an environment as a graph and, therefore, may be applied to aiding navigation in the real world and information spaces, as well as VEs
Using the Java Media Framework to build Adaptive Groupware Applications
Realtime audio and video conferencing has not yet been satisfactorily integrated into web-based groupware environments. Conferencing tools are at best only loosely linked to other parts of a shared working environment, and this is in part due to their implications for resource allocation and management. The Java Media Framework offers a promising means of redressing this situation. This paper describes an architecture for integrating the management of video and audio conferences into the resource allocation mechanism of an existing web-based groupware framework. The issue of adaptation is discussed and a means of initialising multimedia session parameters based on predicted QoS is described
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