Geometry‐specified troposphere decorrelation for subcentimeter real‐time kinematic solutions over long baselines

Real‐time kinematic (RTK) GPS techniques have been extensively developed for applications including surveying, structural monitoring, and machine automation. Limitations of the existing RTK techniques that hinder their applications for geodynamics purposes are twofold: (1) the achievable RTK accuracy is on the level of a few centimeters and the uncertainty of vertical component is 1.5–2 times worse than those of horizontal components and (2) the RTK position uncertainty grows in proportional to the base‐torover distances. The key limiting factor behind the problems is the significant effect of residual tropospheric errors on the positioning solutions, especially on the highly correlated height component. This paper develops the geometry‐specified troposphere decorrelation strategy to achieve the subcentimeter kinematic positioning accuracy in all three components. The key is to set up a relative zenith tropospheric delay (RZTD) parameter to absorb the residual tropospheric effects and to solve the established model as an ill���posed problem using the regularization method. In order to compute a reasonable regularization parameter to obtain an optimal regularized solution, the covariance matrix of positional parameters estimated without the RZTD parameter, which is characterized by observation geometry, is used to replace the quadratic matrix of their “true” values. As a result, the regularization parameter is adaptively computed with variation of observation geometry. The experiment results show that new method can efficiently alleviate the model’s ill condition and stabilize the solution from a single data epoch. Compared to the results from the conventional least squares method, the new method can improve the longrange RTK solution precision from several centimeters to the subcentimeter in all components. More significantly, the precision of the height component is even higher. Several geosciences applications that require subcentimeter real‐time solutions can largely benefit from the proposed approach, such as monitoring of earthquakes and large dams in real‐time, high‐precision GPS leveling and refinement of the vertical datum. In addition, the high‐resolution RZTD solutions can contribute to effective recovery of tropospheric slant path delays in order to establish a 4‐D troposphere tomography.

Raman spectroscopy of selected borate minerals of the pinakiolite group

The Raman spectra of a series of related minerals of the pinakiolite group of minerals have been collected and the spectra related to the mineral structure. These minerals are based upon an isolated BO33- ion. The site symmetry is reduced from D3h to C1. Intense Raman bands are observed for the minerals takeuchiite, pinakiolite, fredrikssonite and azoproite at 1084, 1086, 1086 and 1086 cm-1. These bands are assigned to the ν1 BO33- symmetric stretching mode. Low intensity Raman bands are observed for the minerals at 1345, 1748; 1435, 1748; 1435, 1750; 1436, 1749 cm-1. One probable assignment is to ν3 BO33- antisymmetric stretching mode. Intense Raman bands of takeuchiite, pinakiolite, fredrikssonite and azoproite at 712 cm-1 attributed to the ν2 out-of-plane bending mode. Importantly, through the comparison of the Raman spectra, the molecular structure of borate minerals with ill-defined structures can be obtained.

The impact of gender diversity on performance in services and manufacturing organizations

We present three competing predictions of the organizational gender diversity-performance relationship: a positive linear prediction, a negative linear prediction, and an inverted U-shaped curvilinear prediction. The paper also proposes a moderating effect of industry type (services vs. manufacturing). The predictions were tested using archival quantitative data with a longitudinal design. The results show partial support for the positive linear and inverted U-shaped curvilinear predictions as well as for the proposed moderating effect of industry type. The results help reconcile the inconsistent findings of past research. The findings also show that industry context can strengthen or weaken gender diversity effects.

AITPM national newsletter December 2008 president's report

It’s fast approaching the end of the year and the festive season, and I have a few things on my mind. First, how I’ll fit in all of my holiday plans and projects within my period of leave, which always seems to pass oh so quickly! But more important are the two issues of global financial uncertainty and safe travel. Judging by what is in the media, it appears to be proving difficult for any self respecting financial industry specialist to define and grapple with the so-called current economic crisis, let alone those of us who have not been formally and extensively schooled in the sciences of finance and economics. Perhaps the latter is even more of a “black art” than the discipline of transport planning. The situation has affected all of us with our superannuation and/or share portfolios; however, judging by the still-crowded shopping centres in many areas, the downstream general economic impacts appear to be less serious in Australia than in other developed countries, even with the significant market fluctuations taking place. There are many important decisions facing Australian governments, from the top down, on how they manage their budgets and spending. Infrastructure spending is in competition with other necessities such as the public health system and education. But it appears that infrastructure is an avenue of public spending that, over all time windows, may be able to significantly bolster local economies and that of the nation as a whole. This, however, is against the spectre of deficits. I would suggest that now, more than ever, we as transport and other professionals within the system, should use our knowledge and experience to take a key role in helping government and the private sector make sound decisions on infrastructure planning, delivery and management.

Inclusion of PMU current phasor measurements in a power system state estimator

Three different methods of inclusion of current measurements by phasor measurement units (PMUs) in a power sysetm state estimator is investigated. A comprehensive formulation of the hybrid state estimator incorporating conventional, as well as PMU measurements, is presented for each of the three methods. The behaviour of the elements because of the current measurements in the measurement Jacobian matrix is examined for any possible ill-conditioning of the state estimator gain matrix. The performance of the state estimators are compared in terms of the convergence properties and the varian in the estimated states. The IEEE 14-bus and IEEE 300-bus systems are used as test beds for the study.

Trans digital storytelling : everyday activism, mutable identity and the problem of visibility

Mainstream representations of trans people typically run the gamut from victim to mentally ill and are almost always articulated by non-trans voices. The era of user-generated digital content and participatory culture has heralded unprecedented opportunities for trans people who wish to speak their own stories in public spaces. Digital Storytelling, as an easy accessible autobiographic audio-visual form, offers scope to play with multi-dimensional and ambiguous representations of identity that contest mainstream assumptions of what it is to be ‘male’ or ‘female’. Also, unlike mainstream media forms, online and viral distribution of Digital Stories offer potential to reach a wide range of audiences, which is appealing to activist oriented storytellers who wish to confront social prejudices. However, with these newfound possibilities come concerns regarding visibility and privacy, especially for storytellers who are all too aware of the risks of being ‘out’ as trans. This paper explores these issues from the perspective of three trans storytellers, with reference to the Digital Stories they have created and shared online and on DVD. These examplars are contextualised with some popular and scholarly perspectives on trans representation, in particular embodied and performed identity. It is contended that trans Digital Stories, while appearing in some ways to be quite conventional, actually challenge common notions of gender identity in ways that are both radical and transformative.

Sustaining the next generation of teacher-researchers to work for social justice

This chapter explores a research project involving teachers working with some of the most disadvantaged young people in South Australia, children growing up in poverty, in families struggling with homelessness and ill-health, in the outer southern suburbs. Additionally, there were particular children were struggling with intellectual, emotional and social difficulties which were extreme enough for them not be included in a mainstream class. The research project made two crucial interrelated moves to support teachers to tackle this tough work. First, the project had an explicit social justice agenda. We were not simply researching literacy outcomes, but literacy pedagogies for the students teachers were most worried about. And we wanted to understand how the material conditions of students’ everyday lifeworlds impacted on the working conditions of teachers’ schoolworlds. We sought to open up a discursive space where teachers could talk about poverty, violence, racism and classism in ways that would take them beyond despair and into new imaginings and positive action. Second, the project was designed to start from the urgent questions of early career teachers and to draw on the accumulated practice wisdom of their chosen mentors. Hence we designed not only a teacher-researcher community, but cross-generational networks. Our aim was to build the capacities of both generations to address long-standing educational problems in new ways that drew overtly on their different and complementary resources.

Information accountability for online healthcare social networks

Online social networking has become one of the most popular Internet applications in the modern era. They have given the Internet users, access to information that other Internet based applications are unable to. Although many of the popular online social networking web sites are focused towards entertainment purposes, sharing information can benefit the healthcare industry in terms of both efficiency and effectiveness. But the capability to share personal information; the factor which has made online social networks so popular, is itself a major obstacle when considering information security and privacy aspects. Healthcare can benefit from online social networking if they are implemented such that sensitive patient information can be safeguarded from ill exposure. But in an industry such as healthcare where the availability of information is crucial for better decision making, information must be made available to the appropriate parties when they require it. Hence the traditional mechanisms for information security and privacy protection may not be suitable for healthcare. In this paper we propose a solution to privacy enhancement in online healthcare social networks through the use of an information accountability mechanism.

Raman spectroscopic study of the minerals diadochite and destinezite Fe3+2(PO4,SO4)2(OH)•6H2O – implications for soil science

The two minerals diadochite and destinezite of formula Fe2(PO4,SO4)2(OH)•6H2O have been characterised by Raman spectroscopy and complimented with infrared spectroscopy. These two minerals are both found in soils and are identical except for their morphology. Diadochite is amorphous whereas destinezite is highly crystalline. The spectra of diadochite are broad and ill-defined, whereas the spectra of destinezite are intense and well defined. Bands are assigned to phosphate and sulphate stretching and bending modes. Two symmetric stretching modes for both the phosphate and sulphate symmetric stretching modes support the concept of non-equivalent phosphate and sulphate units in the mineral structure. Multiple water bending and stretching modes imply that non-equivalent water molecules in the structure exist with different hydrogen bond strengths.

Journalism at the movies

Welcome to the first of what will be a regular review essay on films about journalism, covering recent releases as well as looking back at established classics and under-rated obscurities. And there is plenty to write about. Since 2008, and the end of the research period which informed my 2010 book on Journalists in Film there has been a steady stream of films in which a journalist is a primary character, and in which the nature and functioning of journalism is a theme. Morning Glory (Roger Michell, 2010), the story of a ‘serious’ news man (Harrison Ford) having to adapt to the infotainment environment of breakfast news, came out early in 2011 in the United Kingdom. The well-received UK indie Monsters (Gareth Edwards, 2010), a sci-fi with a journalist at its heart, was released in 2010. In The Soloist (Joe Wright, 2009) Robert Downey Jr played a feature journalist who befriends a mentally ill street musician and seeks to rescue him through his writing. Stieg Larsson’s Millennium trilogy has produced three Swedish films, all of them focused on the campaigning journalist Mikael Blomkvist. The first of these is being remade by Hollywood as of this writing.

Autopoiesis, language, literacy and the brain

When we attempt to speak about the relationship between language, literacy, and the brain, we find ourselves ill equipped to deal with these conceptually and qualitatively different phenomena. Immediately we must straddle different academic traditions that treat each of these as separate “things”. Broadly speaking, the study of language firstly belongs to the domain of biology, then to anthropology, sociology, and linguistics. At its most functional, a study of literacy education is a study of a particular technology, its diffusion techniques, and the abilities and motivations of people to adopt, or adapt themselves to, this technology. The brain is most commonly studied in the field of neurology, which is also a sub-discipline of biology, biochemistry, and medicine.

A minor's health rights

This short article considers whether terminally ill adolescents have a right to refuse life sustaining treatment. The article is focused on the UK case of Hannah Jones which attracted a significant amount of media attention in 2008.

Malnutrition and clinical outcomes in elderly patients from a Singapore acute hospital

Older adults, especially those acutely ill, are vulnerable to developing malnutrition due to a range of risk factors. The high prevalence and extensive consequences of malnutrition in hospitalised older adults have been reported extensively. However, there are few well-designed longitudinal studies that report the independent relationship between malnutrition and clinical outcomes after adjustment for a wide range of covariates. Acutely ill older adults are exceptionally prone to nutritional decline during hospitalisation, but few reports have studied this change and impact on clinical outcomes. In the rapidly ageing Singapore population, all this evidence is lacking, and the characteristics associated with the risk of malnutrition are also not well-documented. Despite the evidence on malnutrition prevalence, it is often under-recognised and under-treated. It is therefore crucial that validated nutrition screening and assessment tools are used for early identification of malnutrition. Although many nutrition screening and assessment tools are available, there is no universally accepted method for defining malnutrition risk and nutritional status. Most existing tools have been validated amongst Caucasians using various approaches, but they are rarely reported in the Asian elderly and none has been validated in Singapore. Due to the multiethnicity, cultural, and language differences in Singapore older adults, the results from non-Asian validation studies may not be applicable. Therefore it is important to identify validated population and setting specific nutrition screening and assessment methods to accurately detect and diagnose malnutrition in Singapore. The aims of this study are therefore to: i) characterise hospitalised elderly in a Singapore acute hospital; ii) describe the extent and impact of admission malnutrition; iii) identify and evaluate suitable methods for nutritional screening and assessment; and iv) examine changes in nutritional status during admission and their impact on clinical outcomes. A total of 281 participants, with a mean (+SD) age of 81.3 (+7.6) years, were recruited from three geriatric wards in Tan Tock Seng Hospital over a period of eight months. They were predominantly Chinese (83%) and community-dwellers (97%). They were screened within 72 hours of admission by a single dietetic technician using four nutrition screening tools [Tan Tock Seng Hospital Nutrition Screening Tool (TTSH NST), Nutritional Risk Screening 2002 (NRS 2002), Mini Nutritional Assessment-Short Form (MNA-SF), and Short Nutritional Assessment Questionnaire (SNAQ©)] that were administered in no particular order. The total scores were not computed during the screening process so that the dietetic technician was blinded to the results of all the tools. Nutritional status was assessed by a single dietitian, who was blinded to the screening results, using four malnutrition assessment methods [Subjective Global Assessment (SGA), Mini Nutritional Assessment (MNA), body mass index (BMI), and corrected arm muscle area (CAMA)]. The SGA rating was completed prior to computation of the total MNA score to minimise bias. Participants were reassessed for weight, arm anthropometry (mid-arm circumference, triceps skinfold thickness), and SGA rating at discharge from the ward. The nutritional assessment tools and indices were validated against clinical outcomes (length of stay (LOS) >11days, discharge to higher level care, 3-month readmission, 6-month mortality, and 6-month Modified Barthel Index) using multivariate logistic regression. The covariates included age, gender, race, dementia (defined using DSM IV criteria), depression (defined using a single question “Do you often feel sad or depressed?”), severity of illness (defined using a modified version of the Severity of Illness Index), comorbidities (defined using Charlson Comorbidity Index, number of prescribed drugs and admission functional status (measured using Modified Barthel Index; MBI). The nutrition screening tools were validated against the SGA, which was found to be the most appropriate nutritional assessment tool from this study (refer section 5.6) Prevalence of malnutrition on admission was 35% (defined by SGA), and it was significantly associated with characteristics such as swallowing impairment (malnourished vs well-nourished: 20% vs 5%), poor appetite (77% vs 24%), dementia (44% vs 28%), depression (34% vs 22%), and poor functional status (MBI 48.3+29.8 vs 65.1+25.4). The SGA had the highest completion rate (100%) and was predictive of the highest number of clinical outcomes: LOS >11days (OR 2.11, 95% CI [1.17- 3.83]), 3-month readmission (OR 1.90, 95% CI [1.05-3.42]) and 6-month mortality (OR 3.04, 95% CI [1.28-7.18]), independent of a comprehensive range of covariates including functional status, disease severity and cognitive function. SGA is therefore the most appropriate nutritional assessment tool for defining malnutrition. The TTSH NST was identified as the most suitable nutritional screening tool with the best diagnostic performance against the SGA (AUC 0.865, sensitivity 84%, specificity 79%). Overall, 44% of participants experienced weight loss during hospitalisation, and 27% had weight loss >1% per week over median LOS 9 days (range 2-50). Wellnourished (45%) and malnourished (43%) participants were equally prone to experiencing decline in nutritional status (defined by weight loss >1% per week). Those with reduced nutritional status were more likely to be discharged to higher level care (adjusted OR 2.46, 95% CI [1.27-4.70]). This study is the first to characterise malnourished hospitalised older adults in Singapore. It is also one of the very few studies to (a) evaluate the association of admission malnutrition with clinical outcomes in a multivariate model; (b) determine the change in their nutritional status during admission; and (c) evaluate the validity of nutritional screening and assessment tools amongst hospitalised older adults in an Asian population. Results clearly highlight that admission malnutrition and deterioration in nutritional status are prevalent and are associated with adverse clinical outcomes in hospitalised older adults. With older adults being vulnerable to risks and consequences of malnutrition, it is important that they are systematically screened so timely and appropriate intervention can be provided. The findings highlighted in this thesis provide an evidence base for, and confirm the validity of the current nutrition screening and assessment tools used among hospitalised older adults in Singapore. As the older adults may have developed malnutrition prior to hospital admission, or experienced clinically significant weight loss of >1% per week of hospitalisation, screening of the elderly should be initiated in the community and continuous nutritional monitoring should extend beyond hospitalisation.

ICU nurses' experiences and perspectives of caring for obstetric patients in intensive care: A qualitative study

Aims and objectives.  The aim of this study was to gain an understanding of the experiences and perspectives of intensive care nurses caring for critically ill obstetric patients. Background.  Current literature suggests critically ill obstetric patients need specialised, technically appropriate care to meet their specific needs with which many intensive care nurses are unfamiliar. Furthermore, there is little research and evidence to guide the care of this distinct patient group. Design.  This study used a descriptive qualitative design. Methods.  Two focus groups were used to collect data from 10 Australian intensive care units nurses in May 2007. Open-ended questions were used to guide the discussion. Latent content analysis was used to analyse the data set. Each interview lasted no longer than 60 minutes and was recorded using audio tape. The full interviews were transcribed prior to in-depth analysis to identify major themes. Results.  The themes identified from the focus group interviews were competence with knowledge and skills for managing obstetric patients in the intensive care unit, confidence in caring for obstetric patients admitted to the intensive care unit and acceptance of an expanded scope of practice perceived to include fundamental midwifery knowledge and skills. Conclusion.  The expressed lack of confidence and competence in meeting the obstetric and support needs of critically ill obstetric women indicates a clear need for greater assistance and education of intensive care nurses. This in turn may encourage critical care nurses to accept an expanded role of clinical practice in caring for critically ill obstetric patients. Relevance to clinical practice.  Recognition of the issues for nurses in successfully caring for obstetric patients admitted to an adult intensive care setting provides direction for designing education packages, ensuring specific carepaths and guidelines are in place and that support from a multidisciplinary team is available including midwifery staff.

Super-resolved faces for improved face recognition from surveillance video advances in biometrics

Characteristics of surveillance video generally include low resolution and poor quality due to environmental, storage and processing limitations. It is extremely difficult for computers and human operators to identify individuals from these videos. To overcome this problem, super-resolution can be used in conjunction with an automated face recognition system to enhance the spatial resolution of video frames containing the subject and narrow down the number of manual verifications performed by the human operator by presenting a list of most likely candidates from the database. As the super-resolution reconstruction process is ill-posed, visual artifacts are often generated as a result. These artifacts can be visually distracting to humans and/or affect machine recognition algorithms. While it is intuitive that higher resolution should lead to improved recognition accuracy, the effects of super-resolution and such artifacts on face recognition performance have not been systematically studied. This paper aims to address this gap while illustrating that super-resolution allows more accurate identification of individuals from low-resolution surveillance footage. The proposed optical flow-based super-resolution method is benchmarked against Baker et al.’s hallucination and Schultz et al.’s super-resolution techniques on images from the Terrascope and XM2VTS databases. Ground truth and interpolated images were also tested to provide a baseline for comparison. Results show that a suitable super-resolution system can improve the discriminability of surveillance video and enhance face recognition accuracy. The experiments also show that Schultz et al.’s method fails when dealing surveillance footage due to its assumption of rigid objects in the scene. The hallucination and optical flow-based methods performed comparably, with the optical flow-based method producing less visually distracting artifacts that interfered with human recognition.