15449420
Procurement of enterprise resource planning systems: experiences with some Hong Kong companies
Many cases of adoption of Enterprise Resource Planning (ERP) systems have been reported in the literature. Some of the adopted ERP systems fail to satisfy the customer's requirements, despite the high spending and substantial efforts that have been put into the adoption exercise. This is undoubtedly unsatisfactory. A way to avoid this problem is to adopt a well planned, managed, and controlled ERP procurement process. This paper describes our studies of three Chinese companies in Hong Kong which have adopted ERP systems. We report the experience of these companies, and discuss how the Chinese culture might have shaped the procurement practices in their ERP adoption exercises.
3035412
On the Expected Number of Failures Detected by Subdomain Testing and Random Testing
We investigate the efficacy of subdomain testing and random testing using the expected number of failures detected (the E-measure) as a measure of effectiveness. Simple as it is, the E-measure does provide a great deal of useful information about the fault detecting capability of testing strategies. With the E-measure, we obtain new characterizations of subdomain testing, including several new conditions that determine whether subdomain testing is more or less effective than random testing. Previously, the efficacy of subdomain testing strategies has been analyzed using the probability of detecting at least one failure (the P-measure) for the special case of disjoint subdomains only. On the contrary, our analysis makes use of the E-measure and considers also the general case in which subdomains may or may not overlap. Furthermore, we discover important relations between the two different measures. From these relations, we also derive corresponding characterizations of subdomain testing in terms of the P-measure.
26872843
Promoting the use of information technology in education via lightweight authoring tools
The potential benefits of using information technology in classrooms for enhancing students' learning have been well known, but the realisation of these benefits is often hindered by a number of factors, notably the lack of knowledge/skills of teachers, the lack of appropriate software, insufficient teacher time, and the limitation of hardware and network infrastructure. In this paper, we introduce the approach of using lightweight authoring tools to address the difficulties faced by teachers. This approach has been adopted on many occasions for the continuing development of primary school teachers in Hong Kong, including many workshops and a formal in-service teacher education course. This paper describes how the approach works, and reports our experiences and the very encouraging feedback we received with the use of lightweight authoring tools.
28280708
Prioritization of Test Cases in MUMCUT Test Sets: An Empirical Study
Software developers often have to test a program with a large number of test cases to reveal faults in the program. Some of these test cases may detect faults, and some may not. This leads to an important question on how to arrange the test cases to be executed so that more faults can be detected earlier. With a higher rate of fault detection at the early stage of testing, software developers can then spend more time on fixing the faults. This paper studies several ways of prioritizing test cases in a MUMCUT test set, which guarantees to detect certain types of faults in a Boolean specification written in irredundant disjunctive normal form. Our results suggest a certain ordering that reveals more faults earlier in the testing phases.
17708725
An extended fault class hierarchy for specification-based testing
Kuhn, followed by Tsuchiya and Kikuno, have developed a hierarchy of relationships among several common types of faults (such as variable and expression faults) for specification-based testing by studying the corresponding fault detection conditions. Their analytical results can help explain the relative effectiveness of various fault-based testing techniques previously proposed in the literature. This article extends and complements their studies by analyzing the relationships between variable and literal faults, and among literal, operator, term, and expression faults. Our analysis is more comprehensive and produces a richer set of findings that interpret previous empirical results, can be applied to the design and evaluation of test methods, and inform the way that test cases should be prioritized for earlier detection of faults. Although this work originated from the detection of faults related to specifications, our results are equally applicable to program-based predicate testing that involves logic expressions.
45848865
Optimal improvement of the lower bound performance of partition testing strategies
Although partition testing strategies are intuitively more appealing than random testing, previous empirical and analytical studies show that under unfavourable circumstances partition testing can be very ineffective. The problem of maximally improving the lower bound performance of partition testing by the choice of appropriate test distributions is investigated. An algorithm that generates optimal test distributions for this purpose is proposed and analysed. Moreover, the algorithm can also serve to systematically approximate the proportional sampling strategy, which has previously been proved to be at least as good as random testing.
495865
Achieving Wireline Random Access Throughput in Wireless Networking Via User Cooperation
Well appreciated at the physical layer, user cooperation is introduced here as a diversity enabler for wireless random access (RA) at the medium access control sublayer. This is accomplished through a two-phase protocol in which active users start with a low power transmission attempting to reach nearby users and follow up with a high power transmission in cooperation with the users recruited in the first phase. We show that such a cooperative protocol yields a significant increase in throughput. Specifically, we prove that for networks with a large number of users, the throughput of a cooperative wireless RA network operating over Rayleigh-fading links approaches the throughput of an RA network operating over additive white Gaussian noise links-thus justifying the title of the paper. The message borne out of this result is that user cooperation offers a viable choice for migrating diversity benefits to the wireless RA regime, thus bridging the gap to wireline RA networks, without incurring a bandwidth or energy penalty
13911639
A Cost-Efficient Scheduling Algorithm of On-Demand Broadcasts
In mobile wireless systems data on air can be accessed by a large number of mobile users. Many of these applications including wireless internets and traffic information systems are pull-based, that is, they respond to on-demand user requests. In this paper, we study the scheduling problems of on-demand broadcast environments. Traditionally, the response time of the requests has been used as a performance measure. In this paper we consider the performance as the average cost of request composed of three kinds of costs – access time cost, tuning time cost, and cost of handling failure request. Our main contribution is a self-adaptive scheduling algorithm named LDFC, which computes the delay cost of data item as the priority of broadcast. It costs less compared with some previous algorithms in this context, and shows good adaptability as well even in pure push-based broadcasts.
207155902
Controllable smoke animation with guiding objects
This article addresses the problem of controlling the density and dynamics of smoke (a gas phenomenon) so that the synthetic appearance of the smoke (gas) resembles a still or moving object. Both the smoke region and the target object are represented as implicit functions. As a part of the target implicit function, a shape transformation is generated between an initial smoke region and the target object. In order to match the smoke surface with the target surface, we impose carefully designed velocity constraints on the smoke boundary during a dynamic fluid simulation. The velocity constraints are derived from an iterative functional minimization procedure for shape matching. The dynamics of the smoke is formulated using a novel compressible fluid model which can effectively absorb the discontinuities in the velocity field caused by imposed velocity constraints while reproducing realistic smoke appearances. As a result, a smoke region can evolve into a regular object and follow the motion of the object, while maintaining its smoke appearance.
5687277
A self-adaptive scheduling algorithm of on-demand broadcasts
In mobile wireless systems data on air can be accessed by a large number of mobile users. Many of these applications such as wireless internets and traffic information systems are pull-based, that is, they respond to on-demand user requests. In this paper, we study the scheduling problems of on-demand broadcast environments. Traditionally, the response time of the requests has been used as a performance measure. In this paper we consider the performance as the average cost of request composed of three kinds of costs—access time cost, tuning time cost, and cost of handling failure request. Our main contribution is a self-adaptive scheduling algorithm named LDFC, which computes the delay cost of data item as the priority for broadcast. It performs well compared with some previous algorithms in this context.
2248247
Inviscid and incompressible fluid simulation on triangle meshes
Simulating fluid motion on manifold surfaces is an interesting but rarely explored area because of the difficulty of establishing plausible physical models. In this paper, we introduce a novel method for inviscid fluid simulation over meshes. It can enforce incompressibility on closed surfaces by utilizing a discrete vector field decomposition algorithm. It also includes effective implementations of semi-Lagrangian tracing and velocity interpolation schemes. Different from previous work, our method performs simulations directly on triangle meshes and thus eliminates parametrization distortions. Our implementation can produce convincing fluid motion on surfaces and has interactive performance for meshes with tens of thousands of faces. Copyright © 2004 John Wiley & Sons, Ltd.