Developing speaking assessment tasks to reflect the 'social turn' in language testing

Interactional competence has emerged as a focal point for language testing researchers in recent years. In spoken communication involving two or more interlocutors, the co-construction of discourse is central to successful interaction. The acknowledgement of co-construction has led to concern over the impact of the interlocutor and the separability of performances in speaking tests involving interaction. The purpose of this article is to review recent studies of direct relevance to the construct of interactional competence and its operationalisation by raters in the context of second language speaking tests. The review begins by tracing the emergence of interaction as a criterion in speaking tests from a theoretical perspective, and then focuses on research salient to interactional effectiveness that has been carried out in the context of language testing interviews and group and paired speaking tests.

Optimization of long rural feeders using a genetic algorithm

This paper describes the optimization of conductor size and the voltage regulator location & magnitude of long rural distribution lines. The optimization minimizes the lifetime cost of the lines, including capital costs and losses while observing voltage drop and operational constraints using a Genetic Algorithm (GA). The GA optimization is applied to a real Single Wire Earth Return (SWER) network in regional Queensland and results are presented.

Testing for the non-separability of bi-ambiguous compounds

Separability is a concept that is very difficult to define, and yet much of our scientific method is implicitly based upon the assumption that systems can sensibly be reduced to a set of interacting components. This paper examines the notion of separability in the creation of bi-ambiguous compounds that is based upon the CHSH and CH inequalities. It reports results of an experiment showing that violations of the CHSH and CH inequality can occur in human conceptual combination.

Dynamic coast control of train movement with genetic algorithm

The railway service is now the major transportation means in most of the countries around the world. With the increasing population and expanding commercial and industrial activities, a high quality of railway service is the most desirable. Train service usually varies with the population activities throughout a day and train coordination and service regulation are then expected to meet the daily passengers' demand. Dwell time control at stations and fixed coasting point in an inter-station run are the current practices to regulate train service in most metro railway systems. However, a flexible and efficient train control and operation is not always possible. To minimize energy consumption of train operation and make certain compromises on the train schedule, coast control is an economical approach to balance run-time and energy consumption in railway operation if time is not an important issue, particularly at off-peak hours. The capability to identify the starting point for coasting according to the current traffic conditions provides the necessary flexibility for train operation. This paper presents an application of genetic algorithms (GA) to search for the appropriate coasting point(s) and investigates the possible improvement on fitness of genes. Single and multiple coasting point control with simple GA are developed to attain the solutions and their corresponding train movement is examined. Further, a hierarchical genetic algorithm (HGA) is introduced here to identify the number of coasting points required according to the traffic conditions, and Minimum-Allele-Reserve-Keeper (MARK) is adopted as a genetic operator to achieve fitter solutions.

Railway junction conflict resolution by genetic algorithm

In general, simple and traditional methods are applied to resolve traffic conflicts at railway junctions. They are, however, either inefficient or computationally demanding. A simple genetic algorithm is presented to enable a search for a near optimal resolution to be carried out while meeting the constraints on generation evolution and minimising the search time.

Signalling layout for fixed-block railway lines with real-coded genetic algorithms.

Signalling layout design is one of the keys to railway operations with fixed-block signalling system and it also carries direct effect on overall train efficiency and safety. Based on an analysis to system objectives, this paper presents an optimization model with two objectives in order to devise an efficient signalling layout scheme. Taking into account the present railway line design practices in China, the paper describes steps of the computer-based signalling layout optimisation with real-coded genetic algorithms. A computer-aided system, based on train movement simulator, has also been employed to assist the optimisation process. A case study on a practical railway line has been conducted to make comparisons between the proposed GA-based approach and the current practices. The results illustrate the improved performance of the proposed approach in reducing signal block joints and shortening minimum train service headway.

Power network in loop : a paradigm for real-time simulation and hardware testing

This paper discusses a new paradigm of real-time simulation of power systems in which equipment can be interfaced with a real-time digital simulator. In this scheme, one part of a power system can be simulated by using a real-time simulator; while the other part is implemeneted as a physical system. The only interface of the physical system with the computer-based simulator is through data-acquisition system. The physical system is driven by a voltage-source converter (VSC)that mimics the power system simulated in the real-time simulator. In this papar, the VSC operates in a voltage-control mode to track the point of common coupling voltage signal supplied by the digital simulator. This type of splitting a network in two parts and running a real-time simulation with a physical system in parallel is called a power network in loop here. this opens up the possibility of study of interconnection o f one or several distributed generators to a complex power network. The proposed implementation is verified through simulation studies using PSCAD/EMTDC and through hardware implementation on a TMS320G2812 DSP.

Coast control of train movement with genetic algorithms

Railway service is now the major transportation means in most of the countries around the world. With the increasing population and expanding commercial and industrial activities, a high quality of railway service is the most desirable. We present an application of genetic algorithms (GA) to search for the appropriate coasting point(s) and investigate the possible improvement on fitness of genes. Single and multiple coasting point control with simple GA are developed to attain the solutions and their corresponding train movement is examined. The multiple coasting point control with hierarchical genetic algorithm (HGA) is then proposed to integrate the determination of the number of coasting points.

Coasting control of train operation by genetic algorithm

Balancing between the provision of high quality of service and running within a tight budget is one of the biggest challenges for most metro railway operators around the world. Conventionally, one possible approach for the operator to adjust the time schedule is to alter the stop time at stations, if other system constraints, such as traction equipment characteristic, are not taken into account. Yet it is not an effective, flexible and economical method because the run-time of a train simply cannot be extended without limitation, and a balance between run-time and energy consumption has to be maintained. Modification or installation of a new signalling system not only increases the capital cost, but also affects the normal train service. Therefore, in order to procure a more effective, flexible and economical means to improve the quality of service, optimisation of train performance by coasting point identification has become more attractive and popular. However, identifying the necessary starting points for coasting under the constraints of current service conditions is no simple task because train movement is attributed by a large number of factors, most of which are non-linear and inter-dependent. This paper presents an application of genetic algorithms (GA) to search for the appropriate coasting points and investigates the possible improvement on computation time and fitness of genes.

On-board mass monitoring of heavy vehicles : results of testing program

The Transport Certification Australia on-board mass feasibility project is testing various on-board mass devices in a range of heavy vehicles (HVs). Extensive field tests of on-board mass measurement systems for HVs have been conducted during 2008. These tests were of accuracy, robustness and tamper-evidence of heavy vehicle on-board mass telematics. All the systems tested showed accuracies within approximately +/- 500 kg of gross combination mass or approximately +/- 2% of the attendant weighbridge reading. Analysis of the dynamic data also showed encouraging results and has raised the possibility of use of such dynamic information in tamper evidence in two areas. This analysis was to determine if the use of averaged dynamic data could identify potential tampering or incorrect operating procedures as well as the possibility of dynamic measurements flagging a tamper event by the use of metrics including a tampering index (TIX). Technical and business options to detect tamper events will now be developed during implementation of regulatory OBM system application to Australian heavy vehicles (HVs).

Hierarchical fuzzy logic traffic control at a road junction using genetic algorithms

Traffic control at a road junction by a complex fuzzy logic controller is investigated. The increase in the complexity of junction means more number of input variables must be taken into account, which will increase the number of fuzzy rules in the system. A hierarchical fuzzy logic controller is introduced to reduce the number of rules. Besides, the increase in the complexity of the controller makes formulation of the fuzzy rules difficult. A genetic algorithm based off-line leaning algorithm is employed to generate the fuzzy rules. The learning algorithm uses constant flow-rates as training sets. The system is tested by both constant and time-varying flow-rates. Simulation results show that the proposed controller produces lower average delay than a fixed-time controller does under various traffic conditions.

Optimisation of a class of transportation problems using genetic algorithms

This paper presents a Genetic Algorithms (GA) approach to search the optimized path for a class of transportation problems. The formulation of the problems for suitable application of GA will be discussed. Exchanging genetic information in the sense of neighborhoods will be introduced for generation reproduction. The performance of the GA will be evaluated by computer simulation. The proposed algorithm use simple coding with population size 1 converged in reasonable optimality within several minutes.

Repeat participation in colorectal cancer screening utilizing fecal occult blood testing : a community-based project in a rural setting

Background and Aim: To investigate participation in a second round of colorectal cancer screening using a fecal occult blood test (FOBT) in an Australian rural community, and to assess the demographic characteristics and individual perspectives associated with repeat screening. ---------- Methods: Potential participants from round 1 (50–74 years of age) were sent an intervention package and asked to return a completed FOBT (n = 3406). Doctors of participants testing positive referred to colonoscopy as appropriate. Following screening, 119 participants completed qualitative telephone interviews. Multivariable logistic regression models evaluated the association between round-2 participation and other variables.---------- Results: Round-2 participation was 34.7%; the strongest predictor was participation in round 1. Repeat participants were more likely to be female; inconsistent screeners were more likely to be younger (aged 50–59 years). The proportion of positive FOBT was 12.7%, that of colonoscopy compliance was 98.6%, and the positive predictive value for cancer or adenoma of advanced pathology was 23.9%. Reasons for participation included testing as a precautionary measure or having family history/friends with colorectal cancer; reasons for non-participation included apathy or doctors’ advice against screening.---------- Conclusion: Participation was relatively low and consistent across rounds. Unless suitable strategies are identified to overcome behavioral trends and/or to screen out ineligible participants, little change in overall participation rates can be expected across rounds.

Accountability through high-stakes testing and curriculum change

The motivation for secondary school principals in Queensland, Australia, to investigate curriculum change coincided with the commencement in 2005 of the state government’s publication of school exit test results as a measure of accountability. Aligning the schools’ curriculum with the requirements of high-stakes testing is considered by many academics and teachers as negative outcome of accountability for reasons such as ‘teaching to the test’ and narrowing the curriculum. However, this article outlines empirical evidence that principals are instigating curriculum change to improve published high-stakes test results. Three principals in this study offered several reasons as to why they wished to implement changes to school curricula. One reason articulated by all three was the pressures of accountability, particularly through the publication of high-stakes test data which has now become commonplace in education systems of many Western Nations.