An Ant Colony Optimization Approach to Test Sequence Generation for State-Based Software Testing

Properly generated test suites may not only locate the defects in software systems, but also help in reducing the high cost associated with software testing, ft is often desired that test sequences in a test suite can be automatically generated to achieve required test coverage. However, automatic test sequence generation remains a major problem in software testing. This paper proposes an ant colony optimization approach to automatic test sequence generation for state-based software testing. The proposed approach can directly use UML artifacts to automatically generate test sequences to achieve required test coverage

AD2US: An Automated Approach to Generating Usage Scenarios from UML Activity Diagrams

Although attention has been given to the use of UML (Unified Modelling Language) activity diagrams in the generation of scenarios, thin-threads and test-cases, the processes described in the literature rely heavily on manual intervention either in the information extraction process or in the process of transforming them to an alternate structure. This paper introduces an approach that capture, store and output usage scenarios derived automatically from UML activity diagrams

Towards Automated Test Sequence Generation

The article presents a novel control-flow based test sequence generation technique using UML 2.0 activity diagram, which is a behavioral type of UML diagram. Like other model-based techniques, this technique can be used in the earlier phases of the development process owing to the availability of the design models of the system. The activity diagram model is seamlessly converted into a colored Petri net. We proposed a technique that enables the automatic generation of test sequences according to a given coverage criteria from the execution of the colored Petri nets model. Two types of structural coverage criteria for AD based models, namely sequential and concurrent coverage are described. The proposed technique was applied to an example to demonstrate its feasibility and the generated test sequences were evaluated against selected coverage criteria. This technique can potentially be adapted to service oriented applications, workflows, and concurrent applications

Using Adaptive Agents to Automatically Generate Test Scenarios from the UML Activity Diagrams

Test case generation is one of the most important issues in software testing research and industrial practice. Test scenarios are frequently used to derive test cases for scenario-based software testing. However, the generation of the test scenarios is usually a manual and labor-intensive task. It is desired that test scenarios can be automatically generated. In this paper, we propose an automated approach using adaptive agents to directly generate test scenarios from the UML activity diagrams

Modelling the cutting forces in micro-end-milling using a hybrid approach

This paper presents the development of a cutting force model for the micro-end-milling processes under various cutting conditions using a hybrid approach. Firstly, a finite element (FE) model of orthogonal micro-cutting with a round cutting edge is developed for medium-carbon steel. A number of finite element analyses (FEA) are performed at different uncut chip thicknesses and velocities. Based on the FEA results, the cutting force coefficients are extracted through a nonlinear algorithm to establish a relationship with the uncut chip thickness and cutting speed. Then, the cutting force coefficients are integrated into a mechanistic cutting force model, which can predict cutting forces under different cutting conditions. In order to account for the cutting edge effect, an effective rake angle is employed for the determination of the cutting force. A comparison of the prediction and experimental measured cutting forces has shown that the developed method provides accurate results

Highly-doped SiC resonator with ultra-large tuning frequency range by Joule heating effect

Tuning the natural frequency of a resonator is an innovative approach for the implementation of mechanical resonators in a broad range of fields such as timing applications, filters or sensors. The conventional electrothermal technique is not favorable towards large tuning range because of its reliance on metallic heating elements. The use of metallic heaters could limit the tuning capability due to the mismatch in thermal expansion coefficients of materials forming the resonator. To solve this drawback, herein, the design, fabrication, and testing of a highly-doped SiC bridge resonator that excludes the use of metallic material as a heating element has been proposed. Instead, free-standing SiC structure functions as the mechanical resonant component as well as the heating element. Through the use of the Joule heating effect, a frequency tuning capability of almost ∆f/fo ≈ 80% has been demonstrated. The proposed device also exhibited a wide operating frequency range from 72.3 kHz to 14.5 kHz. Our SiC device enables the development of highly sensitive resonant-based sensors, especially in harsh environments

Investigation into the microstructure and dynamic compressive properties of selective laser melted Ti–6Al–4V alloy with different heating treatments

As a commonly used engineering material, the mechanical properties of titanium alloy under dynamic loads are closely related to their microstructure. In this work, the effects of solution treatment (ST) and solution and aging treatment (SAT) on the microstructure and dynamic compressive properties of Ti–6Al–4V alloy manufactured by selective laser melting were studied. The results showed that the microstructure of selective laser melted Ti–6Al–4V consisted of nearly full acicular α′ martensite, then the acicular α′ martensite was decomposed into α+β phase with basket-weave morphology with solution treatment. Clusters of α2 particles with size of several hundred nanometers were precipitated in the α plates further with solution and aging treatment. The ultimate compressive strength (UCS) of selective laser melted TC4 alloy was increased with the increasing strain rate, showing strong strain rate hardening effect. Stress collapse happened once the strain exceeded 1500/s, which is the dominant failure model of selective laser melted TC4 under impacting load. As expected, the UCS of the ST sample decreased, but the ductility increased compared with the as-built sample; however, both the UCS and ductility of the SAT samples were enhanced synergistically due to the widely distributed α2 precipitates. Besides, the SAT samples had the highest energy absorption compared with the as-built and ST counterparts under the same conditions, indicating that the SAT samples had better load-bearing capacities

Robust 2 − ∞ Filtering for Takagi-Sugeno Fuzzy Systems with Norm-Bounded Uncertainties

We study the filter design problem for Takagi-Sugeno fuzzy systems which are subject to norm-bounded uncertainties in each subsystem. As we know that the Takagi-Sugeno fuzzy linear systems can be used to represent smooth nonlinear systems, the studied plants can also be uncertain complex systems. We suppose to design a filter with the order of the original system which is also dependent on the normalized fuzzy-weighting function; that is, the filter is also a Takagi-Sugeno fuzzy filter. With the augmentation technique, an uncertain filtering error system can be obtained and the system matrices in the filtering error system are reorganized into two categories (without uncertainties and with uncertainties). For the filtering error system, we have two objectives. (1) The first one is that the filtering error system should be robust stable; that is, the filtering error system is stable though there are uncertainties in the original system. (2) The second one is that the robust energy-to-peak performance should be guaranteed. With the well-known Finsler's lemma, we provide the conditions for the robust energy-to-peak performance of the filtering error system in which three slack matrices are introduced. Finally, a numerical example is used to show the effectiveness of the proposed design methodology