Photovoltaic DC-DC module integrated converter for novel cascaded and bypass grid connection topologies - design and optimisation

Grid connected photovoltaic (PV) inverters fall into three broad categories - central, string and module integrated converters (MICs). MICs offer many advantages in performance and flexibility, but are at a cost disadvantage. Two alternative novel approaches proposed by the author - cascaded dc-dc MICs and bypass dc-dc MICs - integrate a simple non-isolated intelligent dc-dc converter with each PV module to provide the advantages of dc-ac MICs at a lower cost. A suitable universal 150 W 5 A dc-dc converter design is presented based on two interleaved MOSFET half bridges. Testing shows zero voltage switching (ZVS) keeps losses under 1 W for bi-directional power flows up to 15 W between two adjacent 12 V PV modules for the bypass application, and efficiencies over 94% for most of the operational power range for the cascaded converter application. Based on the experimental results, potential optimizations to further reduce losses are discussed.

Design optimisation of ironless motors based on magnet selection

This paper considers the design of a radial flux permanent magnet iron less core brushless DC motor for use in an electric wheel drive with an integrated epicyclic gear reduction. The motor has been designed for a continuous output torque of 30 Nm and peak rating of 60 Nm with a maximum operating speed of 7000 RPM. In the design of brushless DC motors with a toothed iron stator the peak air-gap magnetic flux density is typically chosen to be close to that of the remanence value of the magnets used. This paper demonstrates that for an ironless motor the optimal peak air-gap flux density is closer to the maximum energy product of the magnets used. The use of a radial flux topology allows for high frequency operation and can be shown to give high specific power output while maintaining a relatively low magnet mass. Two-dimensional finite element analysis is used to predict the air-gap flux density. The motor design is based around commonly available NdFeB bar magnet size

Design optimisation of ironless motors based on magnet selection

This paper considers the design of a radial flux permanent magnet ironless core brushless DC motor for use in an electric wheel drive with an integrated epicyclic gear reduction. The motor has been designed for a continuous output torque of 30 Nm and peak rating of 60 Nm with a maximum operating speed of 7000 RPM. In the design of brushless DC motors with a toothed iron stator the peak air-gap magnetic flux density is typically chosen to be close to that of the remanence value of the magnets used. This paper demonstrates that for an ironless motor the optimal peak air-gap flux density is closer to the maximum energy product of the magnets used. The use of a radial flux topology allows for high frequency operation and can be shown to give high specific power output while maintaining a relatively low magnet mass. Two-dimensional finite element analysis is used to predict the airgap flux density. The motor design is based around commonly available NdFeB bar magnet size

Gene expression profiling in human breast cancer – toward personalised therapeutics?

The most integrated approach toward understanding the multiple molecular events and mechanisms by which cancer may develop is the application of gene expression profiling using microarray technologies. As molecular alterations in breast cancer are complex and involve cross-talk between multiple cellular signalling pathways, microarray technology provides a means of capturing and comparing the expression patterns of the entire genome across multiple samples in a high throughput manner. Since the development of microarray technologies, together with the advances in RNA extraction methodologies, gene expression studies have revolutionised the means by which genes suitable as targets for drug development and individualised cancer treatment can be identified. As of the mid-1990s, expression microarrays have been extensively applied to the study of cancer and no cancer type has seen as much genomic attention as breast cancer. The most abundant area of breast cancer genomics has been the clarification and interpretation of gene expression patterns that unite both biological and clinical aspects of tumours. It is hoped that one day molecular profiling will transform diagnosis and therapeutic selection in human breast cancer toward more individualised regimes. Here, we review a number of prominent microarray profiling studies focussed on human breast cancer and examine their strengths, their limitations, clinical implications including prognostic relevance and gene signature significance along with potential improvements for the next generation of microarray studies.

Environmental sustainability of urban road transport : an integrated analysis for life cycle emission impact

Despite of significant contributions of urban road transport to global economy and society, it is one of the largest sources of local and global emission impact. In order to address the environmental concerns of urban road transport it is imperative to achieve a holistic understanding of contributory factors causing emissions which requires a complete look onto its whole life cycle. Previous studies were mainly based on segmental views which mostly studied environmental impacts of individual transport modes and very few considered impacts other than operational phase. This study develops an integrated life cycle inventory model for urban road transport emissions from a holistic modal perspective. Singapore case was used to demonstrate the model. Results show that total life cycle greenhouse gas emission from Singapore’s road transport sector is 7.8 million tons per year. The total amount of criteria air pollutants are also estimated in this study.

Geographic remoteness, area-level socioeconomic disadvantage and inequalities in colorectal cancer survival in Queensland : a multilevel analysis

Background To explore the impact of geographical remoteness and area-level socioeconomic disadvantage on colorectal cancer (CRC) survival. Methods Multilevel logistic regression and Markov chain Monte Carlo simulations were used to analyze geographical variations in five-year all-cause and CRC-specific survival across 478 regions in Queensland Australia for 22,727 CRC cases aged 20–84 years diagnosed from 1997–2007. Results Area-level disadvantage and geographic remoteness were independently associated with CRC survival. After full multivariate adjustment (both levels), patients from remote (odds Ratio [OR]: 1.24, 95%CrI: 1.07-1.42) and more disadvantaged quintiles (OR = 1.12, 1.15, 1.20, 1.23 for Quintiles 4, 3, 2 and 1 respectively) had lower CRC-specific survival than major cities and least disadvantaged areas. Similar associations were found for all-cause survival. Area disadvantage accounted for a substantial amount of the all-cause variation between areas. Conclusions We have demonstrated that the area-level inequalities in survival of colorectal cancer patients cannot be explained by the measured individual-level characteristics of the patients or their cancer and remain after adjusting for cancer stage. Further research is urgently needed to clarify the factors that underlie the survival differences, including the importance of geographical differences in clinical management of CRC.

Rapid aminoacidemia enhances myofibrillar protein synthesis and anabolic intramuscular signaling responses after resistance exercise

Background: Ingestion of whey or casein yields divergent patterns of aminoacidemia that influence whole-body and skeletal muscle myofibrillar protein synthesis (MPS) after exercise. Direct comparisons of the effects of contrasting absorption rates exhibited by these proteins are confounded by their differing amino acid contents. Objective: Our objective was to determine the effect of divergent aminoacidemia by manipulating ingestion patterns of whey protein alone on MPS and anabolic signaling after resistance exercise. Design: In separate trials, 8 healthy men consumed whey protein either as a single bolus (BOLUS; 25-g dose) or as repeated, small, "pulsed" drinks (PULSE; ten 2.5-g drinks every 20 min) to mimic a more slowly digested protein. MPS and phosphorylation of signaling proteins involved in protein synthesis were measured at rest and after resistance exercise. Results: BOLUS increased blood essential amino acid (EAA) concentrations above those of PULSE (162% compared with 53%, P < 0.001) 60 min after exercise, whereas PULSE resulted in a smaller but sustained increase in aminoacidemia that remained elevated above BOLUS amounts later (180-220 min after exercise, P < 0.05). Despite an identical net area under the EAA curve, MPS was elevated to a greater extent after BOLUS than after PULSE early (1-3 h: 95% compared with 42%) and later (3-5 h: 193% compared with 121%) (both P < 0.05). There were greater changes in the phosphorylation of the Akt-mammalian target of rapamycin pathway after BOLUS than after PULSE. Conclusions: Rapid aminoacidemia in the postexercise period enhances MPS and anabolic signaling to a greater extent than an identical amount of protein fed in small pulses that mimic a more slowly digested protein. A pronounced peak aminoacidemia after exercise enhances protein synthesis.

Utilizing Wide-Area Signals for off-center SVCs to damp interarea oscillations

Wide-Area Measurement Systems (WAMS) provide the opportunity of utilizing remote signals from different locations for the enhancement of power system stability. This paper focuses on the implementation of remote measurements as supplementary signals for off-center Static Var Compensators (SVCs) to damp inter-area oscillations. Combination of participation factor and residue method is used for the selection of most effective stabilizing signal. Speed difference of two generators from separate areas is identified as the best stabilizing signal and used as a supplementary signal for lead-lag controller of SVCs. Time delays of remote measurements and control signals is considered. Wide-Area Damping Controller (WADC) is deployed in Matlab Simulink framework and is tested under different operating conditions. Simulation results reveal that the proposed WADC improve the dynamic characteristic of the system significantly.

Smart grid-demand side response model to mitigate prices and peak impact on the electrical system

The aims of this project is to develop demand side response model which assists electricity consumers who are exposed to the market price through aggregator to manage the air-conditioning peak electricity demand. The main contribution of this research is to show how consumers can optimise the energy cost caused by the air-conditioning load considering the electricity market price and network overload. The model is tested with selected characteristics of the room, Queensland electricity market data from Australian Energy Market Operator and data from the Bureau of Statistics on temperatures in Brisbane, during weekdays on hot days from 2011 - 2012.

The interface of acute and aged care : the role of the nurse in a provincial area

Objective This study was to investigate issues that arose from pre-admission to post-discharge, for people in Toowoomba, Queensland over the age of 65 admitted to an acute facility. This paper concentrates on a significant concern that emerged from the large amount of data collected during this project, that is,the role of the nurse in the continuum of health care involving elderly people. Method The study involved a multi-site, multi-agency and multi-method (qualitative and quantitative) approach. Data was collected from regional service providers, the Department of Health and Aged Care (DHAC), the Australian Bureau of Statistics (ABS), Home and Community Care (HACC), the Aged Care Assessment Team (ACAT), elderly people who had been discharged from regional hospitals and their carers, residents of regional aged care facilities, area health professionals and elderly regional hospital inpatients. Results The data indicated that nurses in this provincial area currently play a limited role in preadmission planning, being mostly concerned with elective surgery, especially joint replacements. While nurses deliver the majority of care during hospitalisation, they do not appear to be cognizant of the needs of the elderly regarding post-acute discharge. Conclusion The recent introduction of the model of nurse case management in the acute sector appears to be a positive development that will streamline and optimise the health care of the elderly across the continuum in the Toowoomba area. The paper recommends some strategies, such as discharge liaison nurses based in Emergency Departments and the expansion of the nurse case management role, which would optimise care for the elderly person at the interface of care.

Characteristics of chemotherapy practice in rural and remote area health facilities in Queensland

Objective The overall objective of this study was to document the nature of the chemotherapy nursing practice of rural and remote area nurses in Queensland. Design A questionnaire survey that elicited descriptive quantitative and qualitative data. Setting Forty-seven rural and remote area health facilities in Queensland involved in the administration of chemotherapy. Subjects Sixty-seven Queensland rural and remote area nurses involved in the administration of cytotoxic drugs. Main outcome measures: Characteristics of chemotherapy practice including context of practice, amount and type of chemotherapy administered, logistical problems, level of support from referral centres, policies and procedures, safety issues. Results The results indicate that the risks to nursing staff and the potential for poor patient outcomes are higher than in specialist chemotherapy facilities. This is largely due to the human and material resource constraints characteristic of rural practice. These include a lack of understanding on the part of metropolitan-based health departments and the specialist cancer centres that refer patients to rural areas of the constraints that may adversely influence patient outcomes. Conclusions It is essential that steps are taken to ensure that rural and remote area cancer patients have equitable access to safe and competent chemotherapy care delivered in their choice of context, and the results of this study provide guidance on ways that this can be achieved.

Retaining rural and remote area nurses : The Queensland, Australia experience

Because higher-than-average turnover rates for nurses who work in remote and rural areas are the norm, the authors conducted a study to identify professional and personal factors that influenced rural nurses’ decisions to resign. Using a mail survey, the authors gathered qualitative and quantitative data from nurses who had resigned from rural and remote areas in Queensland, Australia. Their findings, categorized into professional and rural influences, highlight the importance of work force planning strategies that capitalize on the positive aspects of rural and remote area practice, to retain nurses in nonmetropolitan areas.

Integrated Lean Six Sigma approach for patient flow improvement in hospital emergency department

Because of increased competition between healthcare providers, higher customer expectations, stringent checks on insurance payments and new government regulations, it has become vital for healthcare organisations to enhance the quality of the care they provide, to increase efficiency, and to improve the cost effectiveness of their services. Consequently, a number of quality management concepts and tools are employed in the healthcare domain to achieve the most efficient ways of using time, manpower, space and other resources. Emergency departments are designed to provide a high-quality medical service with immediate availability of resources to those in need of emergency care. The challenge of maintaining a smooth flow of patients in emergency departments is a global problem. This study attempts to improve the patient flow in emergency departments by considering Lean techniques and Six Sigma methodology in a comprehensive conceptual framework. The proposed research will develop a systematic approach through integration of Lean techniques with Six Sigma methodology to improve patient flow in emergency departments. The results reported in this paper are based on a standard questionnaire survey of 350 patients in the Emergency Department of Aseer Central Hospital in Saudi Arabia. The results of the study led us to determine the most significant variables affecting patient satisfaction with patient flow, including waiting time during patient treatment in the emergency department; effectiveness of the system when dealing with the patient’s complaints; and the layout of the emergency department. The proposed model will be developed within a performance evaluation metric based on these critical variables, to be evaluated in future work within fuzzy logic for continuous quality improvement.

Beyond compliance : project on an integrated systems approach for pest risk management in South East Asia

The Beyond Compliance project, which began in July 2011 with funding from the Standards and Trade Development Facility for 2 years, aims to enhance competency and confidence in the South East Asian sub-region by applying a Systems Approach for pest risk management. The Systems Approach involves the use of integrated measures, at least two of which are independent, that cumulatively reduce the risk of introducing exotic pests through trade. Although useful in circumstances where single measures are inappropriate or unavailable, the Systems Approach is inherently more complicated than single-measure approaches, which may inhibit its uptake. The project methodology is to take prototype decision-support tools, such as Control Point-Bayesian Networks (CP-BN), developed in recent plant health initiatives in other regions, including the European PRATIQUE project, and to refine them within this sub-regional context. Case studies of high-priority potential agricultural trade will be conducted by National Plant Protection Organizations of participating South East Asian countries in trials of the tools, before further modifications. Longer term outcomes may include: more robust pest risk management in the region (for exports and imports); greater inclusion of stakeholders in development of pest risk management plans; increased confidence in trade negotiations; and new opportunities for trade.

Stakeholder engagement and asset management : a case study of the Gold Coast airport, Queensland

One of the fastest growing industries – aviation – faces serious and compounding challenges in maintaining healthy relationships with community stakeholders. One area in aviation creating community conflict is noise pollution. However, current understandings of the factors that affect noise annoyance of the community are poorly conceptualized. More importantly, the way community needs and expectations could be incorporated in airport governance has been inadequately framed to address the issue of aircraft noise. This paper proposes the util-ity of adopting an integrated strategic asset management (ISAM) framework [1] to explore the dynamic nature of relationships between and airport and its surrounding area. The case of the Gold Coast Airport (OOL) operator and community stakeholders is used. This paper begins with an overview of the ISAM framework in the context of airport governance and sustainable development – as a way to find a balance between economic opportunities and societal concerns through stakeholder engagement. Next, an exploratory case study is adopted as a method to explore the noise-related complaints, complainants, and possible causes. Fol-lowing this, the paper reviews three approaches to community stakeholder engagement in Australia, Japan, and UK and discusses their implications in the con-text of OOL. The paper concludes with a contention that airport governance is likely to be much more effective with the adoption of ISAM framework than without it.