Effect of pedestrian movement on MIMO-OFDM channel capacity in an indoor environment

The rapid growth of mobile telephone use, satellite services, and now the wireless Internet and WLANs are generating tremendous changes in telecommunication and networking. As indoor wireless communications become more prevalent, modeling indoor radio wave propagation in populated environments is a topic of significant interest. Wireless MIMO communication exploits phenomena such as multipath propagation to increase data throughput and range, or reduce bit error rates, rather than attempting to eliminate effects of multipath propagation as traditional SISO communication systems seek to do. The MIMO approach can yield significant gains for both link and network capacities, with no additional transmitting power or bandwidth consumption when compared to conventional single-array diversity methods. When MIMO and OFDM systems are combined and deployed in a suitable rich scattering environment such as indoors, a significant capacity gain can be observed due to the assurance of multipath propagation. Channel variations can occur as a result of movement of personnel, industrial machinery, vehicles and other equipment moving within the indoor environment. The time-varying effects on the propagation channel in populated indoor environments depend on the different pedestrian traffic conditions and the particular type of environment considered. A systematic measurement campaign to study pedestrian movement effects in indoor MIMO-OFDM channels has not yet been fully undertaken. Measuring channel variations caused by the relative positioning of pedestrians is essential in the study of indoor MIMO-OFDM broadband wireless networks. Theoretically, due to high multipath scattering, an increase in MIMO-OFDM channel capacity is expected when pedestrians are present. However, measurements indicate that some reductions in channel capacity could be observed as the number of pedestrians approaches 10 due to a reduction in multipath conditions as more human bodies absorb the wireless signals. This dissertation presents a systematic characterization of the effects of pedestrians in indoor MIMO-OFDM channels. Measurement results, using the MIMO-OFDM channel sounder developed at the CSIRO ICT Centre, have been validated by a customized Geometric Optics-based ray tracing simulation. Based on measured and simulated MIMO-OFDM channel capacity and MIMO-OFDM capacity dynamic range, an improved deterministic model for MIMO-OFDM channels in indoor populated environments is presented. The model can be used for the design and analysis of future WLAN to be deployed in indoor environments. The results obtained show that, in both Fixed SNR and Fixed Tx for deterministic condition, the channel capacity dynamic range rose with the number of pedestrians as well as with the number of antenna combinations. In random scenarios with 10 pedestrians, an increment in channel capacity of up to 0.89 bits/sec/Hz in Fixed SNR and up to 1.52 bits/sec/Hz in Fixed Tx has been recorded compared to the one pedestrian scenario. In addition, from the results a maximum increase in average channel capacity of 49% has been measured while 4 antenna elements are used, compared with 2 antenna elements. The highest measured average capacity, 11.75 bits/sec/Hz, corresponds to the 4x4 array with 10 pedestrians moving randomly. Moreover, Additionally, the spread between the highest and lowest value of the the dynamic range is larger for Fixed Tx, predicted 5.5 bits/sec/Hz and measured 1.5 bits/sec/Hz, in comparison with Fixed SNR criteria, predicted 1.5 bits/sec/Hz and measured 0.7 bits/sec/Hz. This has been confirmed by both measurements and simulations ranging from 1 to 5, 7 and 10 pedestrians.

Adverse health effects to air pollution and guidelines to prevent them

This is the first in a series of four articles which will explore different aspects of air pollution, its impact on health and challenges in defining the boundaries between impact and nonimpact on health. Hardly a new topic one might say. Indeed, it’s been an issue for centuries, millennia even! For example, Pliny the Elder (AD 23-79), a Roman officer and author of the ‘Natural History’ recommended that: “…quarry slaves from asbestos mines not be purchased because they die young”, and suggested: “…the use of a respirator, made of transparent bladder skin, to protect workers from asbestos dust.” Closer to modern times, a Danish Proverb states: "Fresh air impoverishes the doctor". While none of these statements are an air quality guideline in a modern sense, they do illustrate that, for a very long time, we have known that there is a link between air quality and health, and that some measures were taken to reduce the impact of the exposure to the pollutants. Obviously, we are much more sophisticated now!

Teaching parallel computing concepts with a desktop computer

Parallel computing is currently used in many engineering problems. However, because of limitations in curriculum design, it is not always possible to offer students specific formal teaching in this topic. Furthermore, parallel machines are still too expensive for many institutions. The latest microprocessors, such as Intel’s Pentium III and IV, embody single instruction multiple-data (SIMD) type parallel features, which makes them a viable solution for introducing parallel computing concepts to students. Final year projects have been initiated utilizing SSE (streaming SIMD extensions) features and it has been observed that students can easily learn parallel programming concepts after going through some programming exercises. They can now experiment with parallel algorithms on their own PCs at home. Keywords

Attractiveness of venture idea amongst expert entrepreneurs : a conjoint analysis

Principal Topic Venture ideas are at the heart of entrepreneurship (Davidsson, 2004). However, we are yet to learn what factors drive entrepreneurs’ perceptions of the attractiveness of venture ideas, and what the relative importance of these factors are for their decision to pursue an idea. The expected financial gain is one factor that will obviously influence the perceived attractiveness of a venture idea (Shepherd & DeTienne, 2005). In addition, the degree of novelty of venture ideas along one or more dimensions such as new products/services, new method of production, enter into new markets/customer and new method of promotion may affect their attractiveness (Schumpeter, 1934). Further, according to the notion of an individual-opportunity nexus venture ideas are closely associated with certain individual characteristics (relatedness). Shane (2000) empirically identified that individual’s prior knowledge is closely associated with the recognition of venture ideas. Sarasvathy’s (2001; 2008) Effectuation theory proposes a high degree of relatedness between venture ideas and the resource position of the individual. This study examines how entrepreneurs weigh considerations of different forms of novelty and relatedness as well as potential financial gain in assessing the attractiveness of venture ideas. Method I use conjoint analysis to determine how expert entrepreneurs develop preferences for venture ideas which involved with different degrees of novelty, relatedness and potential gain. The conjoint analysis estimates respondents’ preferences in terms of utilities (or part-worth) for each level of novelty, relatedness and potential gain of venture ideas. A sample of 32 expert entrepreneurs who were awarded young entrepreneurship awards were selected for the study. Each respondent was interviewed providing with 32 scenarios which explicate different combinations of possible profiles open them into consideration. Results and Implications Results indicate that while the respondents do not prefer mere imitation they receive higher utility for low to medium degree of newness suggesting that high degrees of newness are fraught with greater risk and/or greater resource needs. Respondents pay considerable weight on alignment with the knowledge and skills they already posses in choosing particular venture idea. The initial resource position of entrepreneurs is not equally important. Even though expected potential financial gain gives substantial utility, result indicate that it is not a dominant factor for the attractiveness of venture idea.

Knowledge transfer in project-based organisations : the need for a unique approach

Effective knowledge transfer between infrastructure projects plays a significant role in organisational success and discovery of new technologies, helping to achieve and maintain competitive advantage and, in effect, sustainable infrastructure development. Knowledge is recognised as an important organisational asset that adds value while being shared. To date, research on knowledge transfer has focused on traditional (functional) types of organisations. However, existing knowledge transfer approaches fail to address the issue of unique characteristics of project-based organisations, and the fact that functional and project-based organisations significantly differ in terms of structure, processes, and characteristics. Therefore, there is a need for a different, separate approach for managing knowledge in the project environment. The aim of this chapter is to highlight this need. An extensive literature review is provided on the areas of project management, knowledge management, and organisational structure; this is further supported by empirical evidence from interviews with project management practitioners. Conducting a ‘cross-field’ literature review provides a better understanding of the knowledge transfer mechanisms and its application to projects, and of the importance of knowledge transfer across projects. This research is crucial to gaining a better understanding of knowledge transfer in the project environment. It stresses that there are dissimilarities between project-based organisations and functional organisations in terms of organisational structure, duration of processes, viewpoint of time, response to change, and mobility of people, and that there is a need for a unique strategic approach in order to achieve effective transfer of knowledge. Furthermore, findings presented in this chapter reveal key elements that play an important role in across project knowledge transfer. These elements include: social communication, lessons learned databases, and project management offices.

Probiotics and diarrhoea management in enterally tube fed critically ill patients : what is the evidence?

Objective: The aim of this literature review is to identify the role of probiotics in the management of enteral tube feeding (ETF) diarrhoea in critically ill patients.---------- Background: Diarrhoea is a common gastrointestinal problem seen in ETF patients. The incidence of diarrhoea in tube fed patients varies from 2% to 68% across all patients. Despite extensive investigation, the pathogenesis surrounding ETF diarrhoea remains unclear. Evidence to support probiotics to manage ETF diarrhoea in critically ill patients remains sparse.---------- Method: Literature on ETF diarrhoea and probiotics in critically ill, adult patients was reviewed from 1980 to 2010. The Cochrane Library, Pubmed, Science Direct, Medline and the Cumulative Index of Nursing and Allied Health Literature (CINAHL) electronic databases were searched using specific inclusion/exclusion criteria. Key search terms used were: enteral nutrition, diarrhoea, critical illness, probiotics, probiotic species and randomised clinical control trial (RCT).---------- Results: Four RCT papers were identified with two reporting full studies, one reporting a pilot RCT and one conference abstract reporting an RCT pilot study. A trend towards a reduction in diarrhoea incidence was observed in the probiotic groups. However, mortality associated with probiotic use in some severely and critically ill patients must caution the clinician against its use.---------- Conclusion: Evidence to support probiotic use in the management of ETF diarrhoea in critically ill patients remains unclear. This paper argues that probiotics should not be administered to critically ill patients until further research has been conducted to examine the causal relationship between probiotics and mortality, irrespective of the patient's disease state or projected prophylactic benefit of probiotic administration.

Transforming people, place, and technology : towards re-creative city

This session is titled TRANSFORM! Opportunities and Challenges of Digital Content for Creative Economy. Some of the key concepts for this session include: 1. City / Economy 2. Creativity 3. Digital content 4. Transformation All of us would agree that these terms describe pertinent characteristics of contemporary world, the epithet of which is the ‘network era.’ I was thinking about what I would like to discuss here and what you, leading experts in divergent fields, would be interested to hear about. As the keynote for this session and as one of the first speakers for the entire conference, I see my role as an initiator for imagination, the wilder the better, posing questions rather than answers. Also given the session title Transform!, I wish to change this slightly to Transforming People, Place, and Technology: Towards Re-­creative City in an attempt to take us away a little from the usual image depicted by the given topic. Instead, I intend to sketch a more holistic picture by reflecting on and extrapolating the four key concepts from the urban informatics point of view. To do so, I use ‘city’ as the primary guiding concept for my talk rather than probably more expected ‘digital media’ or ‘creative economy.’ You may wonder what I mean by re-­creative city. I will explain this in time by looking at the key concepts from these four respective angles: 1. Living city 2. Creative city 3. Re-­‐creative city 4. Opportunities and Challenges to arrive at a speculative yet probable image of the city that we may aspire to transform our current cities into. First let us start by considering the ‘living city.’

The Australian Palliative Care Outcomes Collaboration (PCOC) : measuring the quality and outcomes of palliative care on a routine basis

Australia is leading the way in establishing a national system (the Palliative Care Outcomes Collaboration – PCOC) to measure the outcomes and quality of specialist palliative care services and to benchmark services across the country. This article reports on analysis of data collected routinely at point-of-care on 5939 patients treated by the first fifty one services that voluntarily joined PCOC. By March 2009, 111 services have agreed to join PCOC, representing more than 70% of services and more than 80% of specialist palliative care patients nationally. All states and territories are involved in this unique process that has involved extensive consultation and infrastructure and close collaboration between health services and researchers. The challenges of dealing with wide variation in outcomes and practice and the progress achieved to date are described. PCOC is aiming to improve understanding of the reasons for variations in clinical outcomes between specialist palliative care patients and differences in service outcomes as a critical step in an ongoing process to improve both service quality and patient outcomes. What is known about the topic? Governments internationally are grappling with how best to provide care for people with life limiting illnesses and how best to measure the outcomes and quality of that care. There is little international evidence on how to measure the quality and outcomes of palliative care on a routine basis. What does this paper add? The Palliative Care Outcomes Collaboration (PCOC) is the first effort internationally to measure the outcomes and quality of specialist palliative care services and to benchmark services on a national basis through an independent third party. What are the implications for practitioners? If outcomes and quality are to be measured on a consistent national basis, standard clinical assessment tools that are used as part of everyday clinical practice are necessary.

Grade A Taipei junior high school principals’ self-reported leadership practices

The principal’s leadership and curriculum development are considered the core elements for creating a high performing junior high school. In Taiwan, mathematics curriculum reform has been an ongoing topic since 1994. The pedagogy, classroom interactions, and the underlying philosophy of mathematics education have varied with different versions of guidelines. These changes inevitably increase the requirement for principals’ leadership in order to effectively implement the curriculum reform. Principals’ leadership is essential to the success of the implementation in their school. This study aimed to explore and identify the leadership of junior high school principals whose schools had been judged by the Taipei City Government as Grade A junior high schools. Principals’ implementations of the reformed mathematics curriculum were used as examples to generate insights of their leadership. This study drew upon a multiple-case study approach. Data were collected from interviews, observations, and documentations. Bass and Avolio’s (1997) full range leadership theory provided a structure for gaining insight into these principals’ leadership practices. Five Grade A Taipei junior high school principals participated and shared their leadership concepts and experiences. Findings revealed that the leadership preferences of the five principles varied considerably. Management by exception-active, contingent reward, individualised consideration, and idealised influence were Grade A Taipei junior high school principals’ preferred leadership practices. In addition, principals’ leadership strategies associated with these practices were identified. These principals had adopted a range of leadership strategies according to the staff and school needs. Results of this study have implications for both Taiwanese principals and education departments. Principals can enhance their leadership by gaining more understanding about the Grade A principals’ leadership practices and strategies. Taiwanese education departments can improve school leadership training programs by focusing on these practices and strategies, which may also lead to more effective strategies for implementing national curriculum reform.

User-web interactions : how wholistic/analytic web users search the web?

User-Web interactions have emerged as an important research in the field of information science. In this study, we examine extensively the Web searching performed by general users. Our goal is to investigate the effects of users’ cognitive styles on their Web search behavior in relation to two broad components: Information Searching and Information Processing Approaches. We use questionnaires, a measure of cognitive style, Web session logs and think-aloud as the data collection instruments. Our study findings show wholistic Web users tend to adopt a top-down approach to Web searching, where the users searched for a generic topic, and then reformulate their queries to search for specific information. They tend to prefer reading to process information. Analytic users tend to prefer a bottom-up approach to information searching and they process information by scanning search result pages.

Legal responses to climate change

The challenges of climate change pose problems requiring new and innovative legal responses by legal practitioners, government officials and corporate officers. This book addresses a broad range of topic areas where climate change has impact and systematically analyses the key legal responses to climate change, both at the international level and within Australia at federal, State and local levels. In particular, it critically examines: •the rights, duties and market mechanisms established under the international climate change regime •the effect of climate change policies on the implementation of environmental and planning laws •new regimes for the implementation of renewable energy and energy efficiency initiatives •legal frameworks for the implementation of biological and geological sequestration projects (including forest projects and carbon rights); and •legal principles for the design of an effective carbon trading scheme for Australia It also considers the role of the common law including: •the likely response of the law of torts to emerging forms of climate change harm; and •potential liabilities for professionals who must take climate change into account in their decision-making and advice

Interventions for preventing and managing aggressive patients admitted to an acute hospital setting: A systematic review

Background: Violence in health care has been widely reported and health care workers, particularly nurses in acute care settings, are ill-equipped to manage patients who exhibit aggressive traits. Aim: The aim of this systematic review was to establish best practice in the prevention and management of aggressive behaviours in patients admitted to acute hospital settings. Data Sources: An extensive search of the major databases was conducted from 1990 to 2007. The search included published and unpublished studies and papers in English. Review Methods: This review considered any quantitative research study design that evaluated the effectiveness of interventions in the prevention and management of patients who exhibit aggressive behaviours in an acute hospital setting. Each included study was quality assessed by two independent reviewers and data were extracted using the relevant tools developed by the Joanna Briggs Institute. Results: Ten studies met the inclusion criteria and were included in the review. The evidence identified from the studies includes: the benefit of education and training of acute care nurses in aggression management techniques; use of “as required” medications is effective in minimising harm to patients and staff; and that specific interventions such as physical restraint may play a role in managing aggressive behaviours from patients in the acute care setting. Conclusions: This review makes several recommendations for the prevention and management of aggressive behaviours in acute hospital patients. However, due to the lack of high-quality studies conducted in the acute care setting there is huge scope for future research in this area.

The formation of, and change in, the psychological contracts of graduates entering the Queensland public sector

The workplace is evolving and the predicted impact of demographic changes (Salt, 2009; Taylor, 2005) has seen organisations focus on strategic workforce planning. As part of this, many organisations have established or expanded formalised graduate programs to attract graduates and transition them effectively into organisations (McDermott, Mangan, & O'Connor, 2005; Terjesen, Freeman, & Vinnicombe, 2007). The workplace context is also argued to be changing because of the divergence in preferences and priorities across the different generations in the workplace - a topic which is prolific in the popular culture media but is yet to be fully developed in the academic literature (Jorgenson, 2003). The public sector recruits large numbers of graduates and maintains well established graduate programs. Like the workplace context, the public sector is seen to be undergoing a transition to more closely align its practices and processes with that of the private sector (Haynes & Melville Jones, 1999; N. Preston, 1995). Consequently, questions have been raised as to how new workforce entrants see the public sector and its associated attractiveness as an employment option. This research draws together these issues and reviews the formation of, and change in, the psychological contracts of graduates across ten Queensland public sector graduate programs. To understand the employment relationship, the theories of psychological contract and public service motivation are utilised. Specifically, this research focuses on graduates' and managers' expectations over time, the organisational perspective of the employment relationship and how ideology influences graduates' psychological contract. A longitudinal mixed method design, involving individual interviews and surveys, is employed along with significant researcher-practitioner collaboration throughout the research process. A number of important qualitative and quantitative findings arose from this study and there was strong triangulation between results from the two methods. Prior to starting with the organisation, graduates found it difficult to articulate their expectations; however, organisational experience rapidly brought these to the fore. Of the expectations that became salient, most centred on their relationship with their supervisor. Without experience and quality information on which to base their expectations, graduates tended to over-rely on sectoral stereotypes which negatively impacted their psychological contracts. Socialisation only limited affected graduates' psychological contracts and public service motivation. The graduate survey, measured thrice throughout the first 12 months of the graduate program, revealed that the psychological contract and public service motivation results followed a similar trajectory of beginning at mediocre levels, declining between times one and two and increasing between times two and three (although this is not back to original levels). Graduates attributed these to a number of sectoral, organisational, team, supervisory and individual factors. On a theoretical level, this research provides support for the notion of ideology within the psychological contract although it raises some important questions about how it is conceptualised. Additionally, support is given for the manager to be seen as the primary organisational counterpart to the employee in future theoretical and practical work. The research also argues to extend current notions of time within the psychological contract as this seems to be the most divergent and combustible issue across the generations in terms of how the workplace is perceived. A number of practical implications also transpire from the study and the collaborative foundation was highly successful. It is anticipated that this research will make a meaningful contribution to both the theory and practice of the employment relationship with particular regard to graduates entering the public sector.

Which components of heart failure programs are effective? A meta-analysis of the outcomes of structured telephone support or telemonitoring as the primary component of heart failure management in 9,560 patients (Abridged Cochrane Review)

Aims--Telemonitoring (TM) and structured telephone support (STS) have the potential to deliver specialised management to more patients with chronic heart failure (CHF), but their efficacy is still to be proven. Objectives To review randomised controlled trials (RCTs) of TM or STS on all- cause mortality and all-cause and CHF-related hospitalisations in patients with CHF, as a non-invasive remote model of specialised disease-management intervention.--Methods and Results--Data sources:We searched 15 electronic databases and hand-searched bibliographies of relevant studies, systematic reviews, and meeting abstracts. Two reviewers independently extracted all data. Study eligibility and participants: We included any randomised controlled trials (RCT) comparing TM or STS to usual care of patients with CHF. Studies that included intensified management with additional home or clinic visits were excluded. Synthesis: Primary outcomes (mortality and hospitalisations) were analysed; secondary outcomes (cost, length of stay, quality of life) were tabulated.--Results: Thirty RCTs of STS and TM were identified (25 peer-reviewed publications (n=8,323) and five abstracts (n=1,482)). Of the 25 peer-reviewed studies, 11 evaluated TM (2,710 participants), 16 evaluated STS (5,613 participants) and two tested both interventions. TM reduced all-cause mortality (risk ratio (RR 0•66 [95% CI 0•54-0•81], p<0•0001) and STS showed similar trends (RR 0•88 [95% CI 0•76-1•01], p=0•08). Both TM (RR 0•79 [95% CI 0•67-0•94], p=0•008) and STS (RR 0•77 [95% CI 0•68-0•87], p<0•0001) reduced CHF-related hospitalisations. Both interventions improved quality of life, reduced costs, and were acceptable to patients. Improvements in prescribing, patient-knowledge and self-care, and functional class were observed.--Conclusion: TM and STS both appear effective interventions to improve outcomes in patients with CHF.

Social network markets and 'public thought'

This paper approaches its topic in a somewhat crabwise manner, but hopefully by that means it may succeed in reaching its objective without being eaten alive. It comprises a critique of a recent internet post called ‘The Shock of Inclusion’ by Clay Shirky (his contribution to The Edge World Question of 2010), in which he claims (among other things) that ‘the average quality of public thought has collapsed.’