ANGEL: agent-based scheduling for real-time tasks in virtualized clouds

The success of cloud computing makes an increasing number of real-time applications such as signal processing and weather forecasting run in the cloud. Meanwhile, scheduling for real-time tasks is playing an essential role for a cloud provider to maintain its quality of service and enhance the system's performance. In this paper, we devise a novel agent-based scheduling mechanism in cloud computing environment to allocate real-time tasks and dynamically provision resources. In contrast to traditional contract net protocols, we employ a bidirectional announcement-bidding mechanism and the collaborative process consists of three phases, i.e., basic matching phase, forward announcement-bidding phase and backward announcement-bidding phase. Moreover, the elasticity is sufficiently considered while scheduling by dynamically adding virtual machines to improve schedulability. Furthermore, we design calculation rules of the bidding values in both forward and backward announcement-bidding phases and two heuristics for selecting contractors. On the basis of the bidirectional announcement-bidding mechanism, we propose an agent-based dynamic scheduling algorithm named ANGEL for real-time, independent and aperiodic tasks in clouds. Extensive experiments are conducted on CloudSim platform by injecting random synthetic workloads and the workloads from the last version of the Google cloud tracelogs to evaluate the performance of our ANGEL. The experimental results indicate that ANGEL can efficiently solve the real-time task scheduling problem in virtualized clouds.

Evaluation of an evaporation suppressing monolayer system in a controlled wave tank environment: a pilot investigation

Due to long-term drought conditions coupled with the apparent influence of global warming, compounding water loss has been a very serious issue across the vast majority of the Australian continent. During these drought conditions, the evaporative effect outweighs the amount of precipitation being received on a year to year basis. Several methods have been introduced in recent history to inhibit the amount of evaporative loss from various types of water bodies such as the application of thin layer chemical films (monolayers). A series of solvent, solid and suspension derived prototype monolayers, based on ethylene glycol monooctadecyl ether (C18E1), are examined in this current study as an approach to eliminate the problems seen to occur with the previous types of monolayers. This research evaluates the fundamental effect of wind and wave based activity upon these prototype monolayers in an atmospherically controlled enclosure positioned over a large extended water tank using real-time environmental measurements. Selected performance results for the prototype monolayers as measured within the enclosed water tank were compared to results measured from a control monolayer film based on a commonly used octadecanol suspension film. The results show that under varying wind and wave conditions the prototype monolayers inhibit evaporation at a level similar to or better than the octadecanol standard, even when delivered at lower raw dosages.

Beyond construction…..A cross-disciplinary approach to improved learning and teaching in built environment degrees

More than 3.4 million people die each year from water, sanitation and hygiene-related causes. Lack of access to clean water and sanitation kills those most vulnerable in the third world. Leadership in managing cross-disciplinary teams is required to present economical, viable community-based solutions. This project utilised the skills of undergraduates across different disciplines of construction, project management, engineering, design, and communication, to work alongside industry mentors in a team to design, build and present an innovative, sustainable water sanitation solution for a Bangladesh community. The semester-long project enabled undergraduate students to develop skills in client relationships, teamwork, and communication as well as discipline skills of project management and construction. The real-world problem necessitated a paradigm shift away from discipline-based knowledge transference towards skills for the future. The project utilised approaches such as negotiated curriculum and assessment; self-directed, flexible participation in learning; use of social media as a learning tool and cross-disciplinary teamwork. Results from student surveys and interviews indicate that this project directly enhanced students’ work-readiness skills and recognition of the importance of problem solving using cross-disciplinary understandings. Students reported greater self-confidence for tackling future workplace challenges. The results also illustrate strong levels of student satisfaction with the cross-disciplinary approach and the importance of skills in client relationships. The project and its outcomes have implications for how learning and teaching occurs in built environment disciplines and has the potential to create significant impact on the calibre of future built environment graduates.

A domain-specific visual modeling language for testing environment emulation

Software integration testing plays an increasingly important role as the software industry has experienced a major change from isolated applications to highly distributed computing environments. Conducting integration testing is a challenging task because it is often very difficult to replicate a real enterprise environment. Emulating testing environment is one of the key solutions to this problem. However, existing specification-based emulation techniques require manual coding of their message processing engines, therefore incurring high development cost. In this paper, we present a suite of domain-specific visual modelinglanguages to describe emulated testing environments at a highabstraction level. Our solution allows domain experts to model atesting environment from abstract interface layers. These layermodels are then transformed to runtime environment for application testing. Our user study shows that our visual languages are easy to use, yet with sufficient expressive power to model complex testing applications.

Interference-aware coordinated power allocation in autonomous Wi-Fi environment

Self-managed access points (APs) with growing intelligence can optimize their own performances but pose potential negative impacts on others without energy ef ciency. In this paper, we focus on modeling the coordinated interaction among interest-independent and self-con gured APs, and conduct the power allocation case study in the autonomous Wi-Fi scenario. Speci cally, we build a `coordination Wi-Fi platform (CWP), a public platform for APs interacting with each other. OpenWrt-based APs in the physical world are mapped to virtual agents (VAs) in CWP, which communicate with each other through a standard request-reply process de ned as AP talk protocol (ATP).With ATP, an active interference measurement methodology is proposed re ecting both in-range interference and hidden terminal interference, and the Nash bargaining-based power control is further formulated for interference reductions. CWP is deployed in a real of ce environment, where coordination interactions between VAs can bring a maximum 40-Mb/s throughput improvement with the Nash bargaining-based power control in the multi-AP experiments.