Testing timed systems modeled by stream X-machines

Stream X-machines have been used to specify real systems where complex data structures. They are a variety of extended finite state machine where a shared memory is used to represent communications between the components of systems. In this paper we introduce an extension of the Stream X-machines formalism in order to specify systems that present temporal requirements. We add time in two different ways. First, we consider that (output) actions take time to be performed. Second, our formalism allows to specify timeouts. Timeouts represent the time a system can wait for the environment to react without changing its internal state. Since timeous affect the set of available actions of the system, a relation focusing on the functional behavior of systems, that is, the actions that they can perform, must explicitly take into account the possible timeouts. In this paper we also propose a formal testing methodology allowing to systematically test a system with respect to a specification. Finally, we introduce a test derivation algorithm. Given a specification, the derived test suite is sound and complete, that is, a system under test successfully passes the test suite if and only if this system conforms to the specification

Using genetic algorithms to generate test sequences for complex timed systems

The generation of test data for state based specifications is a computationally expensive process. This problem is magnified if we consider that time con- straints have to be taken into account to govern the transitions of the studied system. The main goal of this paper is to introduce a complete methodology, sup- ported by tools, that addresses this issue by represent- ing the test data generation problem as an optimisa- tion problem. We use heuristics to generate test cases. In order to assess the suitability of our approach we consider two different case studies: a communication protocol and the scientific application BIPS3D. We give details concerning how the test case generation problem can be presented as a search problem and automated. Genetic algorithms (GAs) and random search are used to generate test data and evaluate the approach. GAs outperform random search and seem to scale well as the problem size increases. It is worth to mention that we use a very simple fitness function that can be eas- ily adapted to be used with other evolutionary search techniques

Military Facility Cost Estimation System Using Case-Based Reasoning in Korea

This manuscript was submitted on January 22, 2010; approved on July 30, 2010; published online on August 3, 2010. Discussion period open until October 1, 2011; separate discussions must be submitted for individual papers.Numerous cost estimations are made repetitively in the initial stages of construction projects in response to ongoing scope changes and often need to be recalculated frequently. In practice, the square foot method, considered an effective method for time-saving, is widely used. However, this method requires a great amount of effort to calculate a unit price and does not consider the uniqueness of each case. Thus, the use of the square foot method could bring about unwanted consequences. For example, in the case of military projects in Korea, significant differences have been reported between estimations made using this method and the actual costs. In an effort to deal with this challenging issue, this research develops a military facility cost estimation (MilFaCE) system, based on case-based reasoning (CBR), using case data from 422 construction projects at 16 military facilities. Based on system validation experiments involving 10 military officers (engineers), the effectiveness of the system in terms of estimation accuracy and user-friendliness is confirmed. Consequently, this research can be a CBR application example of construction cost estimation and a basis for further research into the development of cost estimate systems. DOI: 10.1061/(ASCE)CP.1943-5487.0000082. (C) 2011 American Society of Civil Engineers.This research was supported by grants (R&D06CIT-A03 and 05CIT-01) from the Korea Ministry of Land, Transport, and Marine Affairs and the Ministry of Defense.

Effects of schedule pressure on construction performance

Accelerating a project can be rewarding. The consequences, however, can be troublesome if productivity and quality are sacrificed for the sake of remaining ahead of schedule, such that the actual schedule benefits are often barely worth the effort. The tradeoffs and paths of schedule pressure and its causes and effects are often overlooked when schedule decisions are being made. This paper analyses the effects that schedule pressure has on construction performance, and focuses on tradeoffs in scheduling. A research framework has been developed using a causal diagram to illustrate the cause-and-effect analysis of schedule pressure. An empirical investigation has been performed by using survey data collected from 102 construction practitioners working in 38 construction sites in Singapore. The results of this survey data analysis indicate that advantages of increasing the pace of work—by working under schedule pressure—can be offset by losses in productivity and quality. The negative effects of schedule pressure arise mainly by working out of sequence, generating work defects, cutting corners, and losing the motivation to work. The adverse effects of schedule pressure can be minimized by scheduling construction activities realistically and planning them proactively, motivating workers, and by establishing an effective project coordination and communication mechanism

Milton And Radical Female Prophets: Millenarianism, Readership, And Poetics

This dissertation investigates the ways in which John Milton and three radical female prophets, Mary Cary, Anna Trapnel, and Dorothy White, utilize literary genres and prophetic forms to build readerships that are favorable to their millennial visions in the 1640s and 1660s. By analyzing their literary strategies to appropriate the idea of the millennium to call for a national renewal through a combination of historicist and formalist approaches, this dissertation seeks to redress critical neglect over how their poetics serves to build pro-republican readerships that advocate their revolutionary causes. More specifically, it examines their development of a plain poetics which informs and defends their political and religious ideals, offering a useful context and perspective for investigating their different literary capitals in formulating literary strategies that intend to form sympathetic readerships. Although Milton and the female prophets pursue the shared goal of linking simplicity and sincerity in worship, social manners, and aesthetics through literary forms, this critical comparison demonstrates that their plain aesthetics differs greatly due to the difference in the literary capital available to them, such as their social status, gender, or political positions. By providing a detailed analysis of their formal choices, poetic experimentations, and stylistic innovations within similar historical, socio-political contexts, this dissertation argues that focusing on differences in literary capital and strategies enables us to properly understand the role of non-conformist aesthetics and the literary achievements of Milton and the female prophets from a more integrated perspective of seventeenth-century prophetic literature. Through a blend of historicist and formalist approaches to their literary characteristics and achievements across gender boundaries, this dissertation provides a case study that helps resolve the critical disjunction in the study of early modern British women’s literature and of early modern British literature

Musical Murals - Augmented Reality Audio Experiences

The appearance of Pow! Wow! Worcester murals of Worcester Massachusetts have become an annual tradition in recent years. The goal of this project is for users to experience complementary audio for the murals in a walking tour around the city. The results of this project showed evidence of a psychological connection between emotions experienced while looking at certain colors and listening to certain sounds, to determine accurate pairings of audios and visuals

Psychometric Properties of the Teacher Version of the Strengths and Difficulties Questionnaire in a Diverse U.S. Sample

This study assesses the utility of the U.S. version of the Strengths and Difficulties Questionnaire (SDQ) teacher form as a screener for mental health and behavior concerns. The SDQ was administered to a community sample of 391 culturally and linguistically diverse students in grades K-6. Internal reliability was assessed using Cronbach’s alpha. Difference by sex and grade were explored through t-tests and one-way analysis of variance (ANOVA), respectively. A confirmatory factor analysis (CFA) was conducted to evaluate factor structure. Results revealed strong internal reliability for the measure as a whole (alpha = .77). Scale alphas were minimally acceptable to satisfactory (alpha range = .69 to .91). Analysis showed significant differences across sex and grade. Males experienced significantly more total difficulties than females, and females demonstrated significantly more prosocial behaviors. Students in lower grades displayed less prosocial behavior than those in grades above them, whereas students in higher grades exhibited more emotional symptoms than those in grades below them. CFA found a five-factor model to be the best fit among those tested, however it was barely acceptable even with modifications. Overall, the U.S. version of the SDQ teacher form was determined to be adequate for identifying students experiencing general difficulties but lacking in the psychometric soundness to help evaluators differentiate among the types of problems with which students may struggle