14076397
The Empirical Studies on Quality Benefits of Reusing Software Components
The benefits of reusing software components have been studied for many years. Several previous studies have concluded that reused components have fewer defects in general than non-reusable components. However, few of these studies have gone a further step, i.e., investigating which type of defects has been reduced because of reuse. Thus, it is suspected that making a software component reusable will automatically improve its quality. This paper presents an on-going industrial empirical study on the quality benefits of reuse. We are going to compare the defects types, which are classified by ODC (orthogonal defect classification), of the reusable component vs. the non-reusable components in several large and medium software systems. The intention is to figure out which defects have been reduced because of reuse and the reasons of the reduction.
6437536
Validation of New Theses on Off-the-Shelf Component Based Development
Using OTS (Off-The-Shelf) components in software development has become increasingly popular in the IT industry. OTS components can be either COTS (Commercial-Off-The-Shelf), or OSS (Open-Source-Software) components. A recent study with seven structured interviews concluded with six theses, which contradicted widely accepted (or simply undisputed) insight. Since the sample size of that study was very small, it is necessary to investigate these theses in a larger and randomized sample. A state-of-the-practice survey in three countries — Norway, Italy, and Germany — has been performed to validate these new theses. Data from 133 OTS component-based projects has been collected. Results of this survey support four and contradict two of the initial theses. The supported theses are: OSS components were mainly used without modification in practice; custom code mainly provided additional functionality; formal OTS selection processes were seldom used; OTS component users managed to get required changes from vendors. The unsupported theses are: standard mismatches were more frequent than architecture mismatches; OTS components were mainly selected based on architecture compliance instead of function completeness.
15181398
An Empirical Study on Off-the-Shelf Component Usage in Industrial Projects
Using OTS (Off-The-Shelf) components in software projects has become increasing popular in the IT industry. After project managers opt for OTS components, they can decide to use COTS (Commercial-Off-The-Shelf) components or OSS (Open Source Software) components instead of building these themselves. This paper describes an empirical study on why project decision-makers use COTS components instead of OSS components, or vice versa. The study was performed in form of an international survey on motivation and risks of using OTS components, conducted in Norway, Italy and Germany. We have currently gathered data on 71 projects using only COTS components and 39 projects using only OSS components, and 5 using both COTS and OSS components. Results show that both COTS and OSS components were used in small, medium and large software houses and IT consulting companies. The overall software system also covers several application domains. Both COTS and OSS were expected to contribute to shorter time-to-market, less development effort and the application of newest technology. However, COTS users believe that COTS component should have good quality, technical support, and will follow the market trend. OSS users care more about the free ownership and openness of the source code. Projects using COTS components had more difficulties in estimating selection effort, following customer requirement changes, and controlling the component's negative effect on system security. On the other hand, OSS user had more difficulties in getting the support reputation of OSS component providers.
15668602
A Survey of Software Development with Open Source Components in Chinese Software Industry
Chinese software companies are increasingly using Open Source Software (OSS) components in system development. Integrating such components into new software systems leads to challenges related to component selection, component integration and testing, licensing compliance, and system maintenance. Although these issues have been investigated industrially in other countries, few state-of-the-practice studies have so far been performed in China and with a representative subset of software companies. It is therefore difficult for Chinese software companies to be aware of special issues, or to plan improvement of OSS-related processes. This paper describes a questionnaire-based survey in Chinese software companies of software development with existing OSS components. Data from 47 finished development projects in 43 companies have been collected. The results show that use of web search engines was the most common method to locate OSS components. Local expertise combined with requirements compliance was the most decisive factors when choosing an identified component. To avoid legal exposure, the common strategy was to use components without licensing constraints. About 84% of the components needed bug fixing or other code changes, rarely relies on support from the OSS community. However, close participation with the OSS community was rare, although most developers meant that this was important.
45728152
An Empirical Study of Variations in COTS-based Software Development Processes in Norwegian IT Industry
38599737
Electronic Homework on the WWW
This paper presents the design of an Intelligent Tutoring System (ITS) MathEH, that is a coached problem solving system, also called "Electronic Homework". In describing the main modules of the system, we emphasize its novel aspects: (1). Using Constraint Logic Programming (CLP) as the domain knowledge representation and automatic reasoning mechanism. (2). A method for probability propagation in Bayesian networks to achieve two adversary requirements: exact probability computation and real-time response. (3). The design decisions about how to deploy MathEH on the WWW.
6271246
Mining Optimal Class Association Rule Set
We define an optimal class association rule set to be the minimum rule set with the same prediction power of the complete class association rule set. Using this rule set instead of the complete class association rule set we can avoid redundant computation that would otherwise be required for mining predictive association rules and hence improve the efficiency of the mining process significantly. We present an efficient algorithm for mining the optimal class association rule set using an upward closure property of pruning weak rules before they are actually generated. We have implemented the algorithm and our experimental results show that our algorithm generates the optimal class association rule set, whose size is smaller than 1/17 of the complete class association rule set on average, in significantly less time than generating the complete class association rule set. Our proposed criterion has been shown very effective for pruning weak rules in dense databases.
27000668
On (g, f, n)-Critical Graphs
3756004
Parameter estimation of multi-dimensional hidden Markov models - a scalable approach
Parameter estimation is a key computational issue in all statistical image modeling techniques. In this paper, we explore a computationally efficient parameter estimation algorithm for multi-dimensional hidden Markov models. 2-D HMM has been applied to supervised aerial image classification and comparisons have been made with the first proposed estimation algorithm. An extensive parametric study has been performed with 3-D HMM and the scalability of the estimation algorithm has been discussed. Results show the great applicability of the explored algorithm to multi-dimensional HMM based image modeling applications.
198665
Enhanced smart-card based license management
In many e-commerce (electronic commerce) situations, the owner of a digital object wants to enforce policies on the object after the object is in the customer's hands. The object can be thought of as being software, because data is often protected by forcing access to it to take place through a particular authorized software (e.g., a "reader" for an encrypted media file, in which case a license to view the movie is, in some sense, a "software license"). One of the ways that were proposed for such policy enforcement is the use of smart cards. We describe an enhanced solution to software license management based on tamper-resistant smart cards. Our public-key protocols for binding software licenses to smart cards improve on previous schemes in that they support flexible and partial transfers of licenses between cards. The license is verified by checking the presence of the associated card. The user can therefore have several software licenses all of which are bound to one card, to avoid juggling several cards in and out of the card reader.
1941921
A grid oriented approach to reusing legacy code in ICENI framework
Legacy systems are valuable assets for organisations. They continuously evolve with new emerged technologies in rapidly changing business environment. ICENI provided an excellent grid middleware framework for developing grid-based systems. It creates an opportunity for legacy systems to evolve in grid environment. In this paper, we propose a component-based reengineering approach which applies software clustering techniques and program slicing techniques to recover components from legacy systems. It supports component encapsulation with JNI and component integration with CXML. The resulting components with core legacy code function in grid environment.