Engineering Commons^™

A Decentralized Latency-Aware Task Allocation And Group Formation Approach With Fault Tolerance For Iot Applications, Muhammad Mudassar, Yanlong Zhai, Lejian Liao, Jun Shen

Faculty of Engineering and Information Sciences - Papers: Part B

Development of internet of things (IoT) and smart devices eased life by offering numerous applications targeting to provide real-time low latency services, but they also brought challenges in handling huge data generated from the powerful computations, to get a job done. Decentralized edge computing could help to achieve latency requirements of the applications by executing them closer to the user at edge of network, but most of the current studies actually deployed centralized approaches for cluster computing at edge, which put extra overhead of cluster formation and management. In this article, we propose to group heterogeneous edge nodes on task …

Facilitating Application-Aware Bandwidth Allocation In The Cloud With One-Step-Ahead Traffic Information, Dian Shen, Junzhou Luo, Fang Dong, Jiahui Jin, Junxue Zhang, Jun Shen

Faculty of Engineering and Information Sciences - Papers: Part B

Bandwidth allocation to virtual machines (VMs) has a significant impact on the performance of communication-intensive big data applications hosted in VMs. It is crucial to accurately determine how much bandwidth to be reserved for VMs and when to adjust it. Past approaches typically resort to predicting the long-term network demands of applications for bandwidth allocation. However, lacking of prediction accuracy, these methods lead to the unpredictable application performance. Recently, it is conceded that the network demands of applications can only be accurately derived right before each of their execution phases. Hence, it is challenging to timely allocate the bandwidth to …

Fast Multi-Resource Allocation With Patterns In Large Scale Cloud Data Center, Jiyuan Shi, Junzhou Luo, Fang Dong, Jiahui Jin, Jun Shen

Faculty of Engineering and Information Sciences - Papers: Part B

How to achieve fast and efficient resource allocation is an important optimization problem of resource management in cloud data center. On one hand, in order to ensure the user experience of resource requesting, the system has to achieve fast resource allocation to timely process resource requests; on the other hand, in order to ensure the efficiency of resource allocation, how to allocate multi-dimensional resource requests to servers needs to be optimized, such that server's resource utilization can be improved. However, most of existing approaches focus on finding out the mapping of each specific resource request to each specific server. This …

Proposed Amendment To Iec/Tr 61000.3.6:2008 For Harmonic Allocation To Loads In Transmission Systems, Tuan Vu, Duane A. Robinson, Victor J. Gosbell, Sarath Perera, Rizah Memisevic

Faculty of Engineering and Information Sciences - Papers: Part B

Ensuring harmonic voltage distortion levels in transmission systems remain below acceptable levels relies on appropriate allocations of emissions to customer loads and bulk supply points. A number of practical issues have been identified with the existing harmonic allocation method for transmission systems in the technical report IEC/TR 61000-3-6:2008, Ed.2: the method to assess the total available power of a busbar, a key component to harmonic allocations, is not intuitive and there is a lack of clarity in the report; the method for sharing planning levels also does not allow unused spare capacity at a busbar to be shared with other …

Household Allocation, Johan Barthelemy

Faculty of Engineering and Information Sciences - Papers: Part A

This chapter explains how to take spatial microdata, of the type we have generated in the previous chapters, and allocate the resulting individuals into household units.

Community Energy Storage For Neutral Voltage Rise Mitigation In Four-Wire Multigrounded Lv Feeders With Unbalanced Solar Pv Allocation, Md Jan E Alam, Kashem M. Muttaqi, Danny Sutanto

Faculty of Engineering and Information Sciences - Papers: Part A

The traditional neutral voltage problem in low-voltage (LV) four-wire multigrounded distribution networks can be aggravated due to an unbalanced allocation of one-phase photovoltaic (PV) units. Inherent limitations restrict the performance of the traditional strategies to mitigate the combined effect of load and PV unbalance. To overcome the shortcoming of traditional approaches, a new dynamic mitigation approach using community energy storage (CES) is proposed in this paper. A power balancing algorithm is developed to perform the balancing operation while minimizing power drawn from the CES. A charge/discharge control strategy is developed that will continuously balance and dynamically adjust the power exchange …

Alleviation Of Neutral-To-Ground Potential Rise Under Unbalanced Allocation Of Rooftop Pv Using Distributed Energy Storage, Md Jan E Alam, Kashem M. Muttaqi, Danny Sutanto

Faculty of Engineering and Information Sciences - Papers: Part A

A high penetration of one-phase rooftop solar photovoltaic (PV) units with unbalanced allocation can create considerable neutral current and neutral potential rise in low voltage (LV) four-wire multigrounded distribution networks, even with balanced loads. Because of the limitations of traditional strategies to mitigate the combined effect of load and PV unbalance, this paper proposes the use of distributed energy storage to reduce the neutral current and neutral potential under a high penetration of unbalanced rooftop solar PV allocation. A power-balancing algorithm based on charge/discharge control is developed to continuously adjust the power exchange with the grid to mitigate the neutral …

Development Of A Public Education Website: Building Bridges Over Water, Angelina Mckee

Agricultural Education and Communication

Website created by Angelina McKee to educate the public about water resource issues. Water is the basic unit of life, water resources are the basis for what societies and ecosystems are founded upon. Water shortages and droughts are more prevalent in our ever-changing world. It is no shock that there are discrepancies between various stockholders on either sides of the dry riverbed. This senior project resulted in the development of a website that addresses global water resources, water use in California, water conservation, and water allocation. The website informs the public on water resources and related issues and will hopefully …

Optimum Allocation Of Sample To Strata And Stages With Simple Additional Constraints, Robert Clark, David Steel

Robert Clark

The optimum allocation of a sample to strata and stages in a stratified two-stage design for a simple cost function is well known. In practice there may be reasons to impose simple additional constraints. It is shown how the theory for optimum allocation can be generalized to account for such constraints. A simple way of assessing the effect that each constraint has on the efficiency of the sample design is developed. This general approach allows several additional constraints that are used in practice to be applied. Data from the 1996 redesign of the Australian Monthly Labour Force Survey are used …

Power Allocation Algorithm In Ofdm-Based Cognitive Radio Systems, Van Vinh Nguyen, Yang Shouyi, Le Chung Tran

Faculty of Engineering and Information Sciences - Papers: Part A

In orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) systems, the optimized algorithms for sub-carrier power allocation face the problems of complex iterative calculation and difficult realization. In this paper, we propose an exponential power distribution function and derive a sub-optimal power allocation algorithm. This algorithm aims to allocate power of in-band subcarriers of cognitive users according to the numerical characteristics of the power distribution function by using a convex optimization numerical method under linear constraints. This algorithm has the advantages of fast calculation speed and easy realization, and reduces the interference to the authorized users, which is caused by …

Voltage Unbalance Emission Allocation Using Constrained Bus Voltage Method In Radial Distribution Networks, Devinda Perera, Philip Ciufo, Sarath Perera, Lasantha Meegahapola

Faculty of Engineering and Information Sciences - Papers: Part A

The International Electrotechnical Committee Technical Report IEC 61000-3-13 is focused on the coordination of voltage unbalance (VU) in power systems by prescribing a methodology to determine individual VU emission allocation limits to installations. This paper provides an alternative VU emission allocation process to that of the IEC Technical Report, which is based on the concept of constrained bus voltage (CBV) method. The proposed methodology can be used in relation to radial distribution networks with symmetrical distribution lines. Several application examples of the proposed methodology are presented. It is shown that the proposed methodology is superior in comparison to the VU …

Optimal Allocation Of Reactive Power Resources To Minimise Losses And Maintain System Security, Eknath Vittal, Lasantha Meegahapola, Damian Flynn, Andrew Keane

Dr Lasantha G Meegahapola

Modern doubly-fed induction generator (DFIG) wind turbines have significant reactive power control capability, even during low wind speed conditions. This can improve system security by providing terminal voltage control at buses in the system. Generally, such control employs the full range of reactive power production from the turbine which can lead to increased system losses. By utilizing optimal power flow analysis, and limiting the range of reactive power production at certain wind farms, system losses can be minimized. If the reactive power of the wind farms are optimized to achieve the minimum system losses this may adversely affect the voltage …

Dynamic Channel Allocation For Mobile Cellular Systems Using A Control Theoretical Approach, Yaya Wei, Chuang Lin, Raad Raad, Fengyuan Ren

Dr Raad Raad

The guard channel scheme in wireless mobile networks has attracted and is still drawing research interest owing to easy implementation and flexible control. Dynamic guard channel schemes have already been proposed in the literature to adapt to varying traffic load. This paper presents a novel control-theoretic approach to dynamically reserve guard channels called PI-Guard Channel (PI-GC) controller that maintains the handoff blocking probability (HBP) to a predefined value; while it still improves the channel resource utilization.

Optimum Allocation Of Sample To Strata And Stages With Simple Additional Constraints, Robert Clark, David Steel

Professor David Steel

The optimum allocation of a sample to strata and stages in a stratified two-stage design for a simple cost function is well known. In practice there may be reasons to impose simple additional constraints. It is shown how the theory for optimum allocation can be generalized to account for such constraints. A simple way of assessing the effect that each constraint has on the efficiency of the sample design is developed. This general approach allows several additional constraints that are used in practice to be applied. Data from the 1996 redesign of the Australian Monthly Labour Force Survey are used …

A New Approach To Harmonic Allocation For Medium-Voltage Installations, Victor J. Gosbell, R A. Barr

Faculty of Engineering and Information Sciences - Papers: Part A

Distributors need to allocate a maximum allowed level of harmonic current to medium-voltage customers to keep voltage distortion acceptable. Tlie paper describes a new approach, based on the concept of voltage droop, requiring much less calculation and data than required by the present approach based on an IEC technical report. The discrepancy between the new method and the present is studied by comparing some carefully selected scenarios. It is shown that the proposed method gives results within 20% of the standards-based approach which makes it a very attractive alternative for harmonic allocation. © Institution of Engineers Australia, 2013.

Evaluations Of Heuristic Algorithms For Teamwork-Enhanced Task Allocation In Mobile Cloud-Based Learning, Geng Sun, Jun Shen, Junzhou Luo, Jianming Yong

Faculty of Engineering and Information Sciences - Papers: Part A

Enhancing teamwork performance is a significant issue in mobile cloud-based learning. We introduce a service oriented system, Teamwork as a Service (TaaS), to realize a new approach for enhancing teamwork performance in the mobile cloud environment. To coordinate most learners' talents and give them more motivation, an appropriate task allocation is necessary. Utilizing the Kolb's learning style (KLS) to refine learner's capabilities, and combining their preferences and tasks' difficulties, we formally describe this problem as a constraint optimization model. Two heuristic algorithms, namely genetic algorithm (GA) and simulated annealing (SA), are employed to tackle the teamwork-enhanced task allocation, and their …

Decentralised Task Allocation Under Space, Time And Communication Constraints For Disaster Domain, Xing Su, Minjie Zhang, Quan Bai

Faculty of Engineering and Information Sciences - Papers: Part A

The coordination of dynamic task allocation based on available resources is very challenging in disaster domains under time, space and communication constraints. In addition, it is also very hard or even impossible to achieve tasks allocation by using a centralised manner with the global knowledge of the working environment. This paper presents a novel decentralised coordination approach for dynamic task allocation by considering space, time and communication constraints in a disaster domain, and workloads and priorities of different tasks. In this approach, a group formation mechanism is proposed to help agents with limited communication range to achieve effective task allocation …

Experience In The Application Of Iec/Tr 61000-3-6 To Harmonic Allocation In Transmission Systems, T J. Browne, V J. Gosbell, S Perera, D A. Robinson, L M. Falla, P J. Windle, A C. D Perera

Faculty of Engineering and Information Sciences - Papers: Part A

Technical report IEC/TR 61000-3-6 is widely used as a guide to harmonic management in HV and MV networks, assisting in coordination of harmonic levels between utility and customer. In 2001, Australia and New Zealand adopted the harmonic standard AS/NZS 61000.3.6, which closely follows the above IEC technical report. As a result, transmission utilities and connected loads are required by government regulations to abide by the harmonic allocations set by the standard. The technical report contains some useful general principles which can be applied to the harmonic management of power systems. However, unexpected difficulties can be found when attempts are made …

Dynamic Channel Allocation For Mobile Cellular Systems Using A Control Theoretical Approach, Yaya Wei, Chuang Lin, Raad Raad, Fengyuan Ren

Faculty of Engineering and Information Sciences - Papers: Part A

The guard channel scheme in wireless mobile networks has attracted and is still drawing research interest owing to easy implementation and flexible control. Dynamic guard channel schemes have already been proposed in the literature to adapt to varying traffic load. This paper presents a novel control-theoretic approach to dynamically reserve guard channels called PI-Guard Channel (PI-GC) controller that maintains the handoff blocking probability (HBP) to a predefined value; while it still improves the channel resource utilization.

Federal/State Relations In Theory And Practice: A Sovereignty Mismatch, Charles T. Dumars

Western Water Law in Transition (Summer Conference, June 3-5)

12 pages.

Contains footnotes.

Western Ground Water Law: Overview And Recent Developments, J. David Aiken

Western Water Law in Transition (Summer Conference, June 3-5)

27 pages.