3890576
Design and experimental analysis of continuous location tracking techniques for Wizard of Oz testing
Wizard of Oz (WOz) testing has shown promise as an effective way to test location-enhanced applications. However, it is challenging to conduct a location-based WOz test because of the dynamic nature of target settings in the field. In particular, continuous location tracking, a major task in such a test, requires a wizard to frequently update a user's location to simulate a location system. This imposes a heavy task load on a wizard. To ease wizards' tasks for location tracking, we designed two techniques, Directional Crossing and Steering, and conducted a field experiment to investigate the performance of the two techniques. A quantitative analysis shows that Directional Crossing and Steering significantly lowered a wizard's task load for location tracking without sacrificing accuracy.
8622581
BrickRoad: a light-weight tool for spontaneous design of location-enhanced applications
It is difficult to design and test location-enhancedapplications. A large part of this difficulty is due to the added complexity of supporting location. Wizard of Oz (WOz) has become an effective technique for the early stage design of location-enhanced applications because it allows designers to test an application prototype bysimulating nonexistent components such as location sensing. However, existing WOz tools 1) require nontrivial effort from designers to specify how a prototype should behave before it can be tested with end users, and 2)support only limited control over application behavior during a test. BrickRoad is a WOz tool for spontaneousdesign of location-enhanced applications. It lowers the threshold to acquiring user feedback and exploring a design space. With BrickRoad, a designer does not need to specify any interaction logic and can experiment on-the-fly with different designs during testing. BrickRoad is a valuable complement to existing tool support for the early stage design of location-enhanced applications.
44498059
Penbuilder: Platform for the Development of Pen-Based User Interface
Pen-based user interfaces is widely used in mobile computing environment, which provides natural, efficient interaction. It has substantial differences from any previous interface and it is difficult to be implemented. A well-designed platform will improve the development of pen-based user interface. In this paper, the architecture of Pen-Book-Page-Paper is presented, which is extended from the metaphor of Pen-Paper. Penbuilder is a development platform based on this architecture. Pen-based user interface can be constructed from three layers of Penbuilder: modal-primitive layer, task-primitive layer and task layer. Each layer provides different extent supports for flexibility and reusability. The components of the platform are discussed in detail and some properties of the platform are argued. Penbuilder is also compliant for the development of distributed user interface. In the section of discussion, we analyze the platform through task tree. The platform provides full supports for extensibility and new interactive devices can be easily added.
5262698
An integrated algorithm of incremental and robust PCA
Principal component analysis (PCA) is a well-established technique in image processing and pattern recognition. Incremental PCA and robust PCA are two interesting problems with numerous potential applications. However, these two issues have only been separately addressed in the previous studies. In this paper, we present a novel algorithm for incremental and robust PCA by seamlessly integrating the two issues together. The proposed algorithm has the advantages of both incremental PCA and robust PCA. Moreover, unlike most M-estimation based robust algorithms, it is computational efficient. Experimental results on dynamic background modelling are provided to show the performance of the algorithm with a comparison to the conventional batch-mode and nonrobust algorithms.
6131842
Adaptive testing of software components
Software components are popular in nowadays software industries. However, how to test software components is a problem since the source code of the software component under test may not be available for the third-party user. In this paper we show that the software component should be tested in an adaptive manner in the sense that the software defect detection rates are estimated on-line by using testing data collected during testing to improve test case selections. In doing so, we use a recursive least squares estimation method to do on-line parameter estimations. This paper further justifies the advantages of the controlled Markov chain (CMC) approach to software testing in particular, and the practicality of the idea of software cybermetics in general.
15691197
Verifying OWL and ORL Ontologies in PVS
The Semantic Web vision is being realized to reach the full potential of the Web. Semantic data modeling is the foundation of the Semantic Web. The Web Ontology Language (OWL) and OWL Rules Language (ORL) provides basic machinery to the semantic mark-up for data. However, there is limited tool support for OWL and no tool support currently for ORL. In this paper, we propose to model OWL and ORL language semantics in PVS specification language so that OWL and ORL ontologies can be transformed and verified in the Prototype Verification System (PVS). PVS user-defined proof strategies are also developed to automate the proof process.
24660543
A note on the lower bounds of signed domination number of a graph
Abstract Let G = (V, E) be a graph. For a function f : V → {−1, 1}, the weight of f is w(f) = Σv ∈ V f(v). For a vertex v in V, we define f[v] = Σu∈N[v] f(u). A signed dominating function of G is a function f : V → {−1, 1} such that f[v] ⩾ 1 for all v ∈ V. The signed domination number γs(G) of G is the minimum weight of a signed dominating function on G. A signed dominating function of a weight γs(G) we call a γs-function of G. In this paper, we study the signed domination problem of general graph, and obtain some lower bounds of the signed domination number of a graph, and show that these lower bounds are sharp, and extend a result in Dunbar et al. (1995).
2533092
State-preserving vs. non-state-preserving leakage control in caches
This paper compares the effectiveness of state-preserving and non-state-preserving techniques for leakage control in caches by comparing drowsy cache and gated-V/sub ss/ for data caches using 70nm technology parameters. To perform the comparison, we introduce "HotLeakage", a new architectural model for subthreshold and gate leakage that explicitly models the effects of temperature, voltage, and parameter variations, and has the ability to recalculate leakage currents dynamically as temperature and voltage change at runtime due to operating conditions, DVS techniques, etc. By comparing drowsy-cache and gated-V/sub ss/ at different L2 latencies and different gate oxide thickness values, we are able to identify a range of operating parameters at which gated-V/sub ss/ is more energy efficient than drowsy-cache, even though gated-V/sub ss/ does not preserve data in cache lines that have been deactivated. We are also able to show potential further benefits of gated-V/sub ss/ if an effective dynamic adaptation technique can be found. These results debunk a fairly widespread belief that state-preserving techniques are inherently superior to non-state-preserving techniques.