Design and development of a solar array drive

The design and development of a dry lubricated direct drive solar array pointing mechanism is discussed for use on the Orbital Test Satellite (OTS), MAROTS, European Communication Satellite (ECS), and others. Results of life testing the original prototype and the OTS mechanism are presented together with an appraisal of expected future development

Analysis of the use and perception of shared mobility: A case study in Western Australia

The sharing economy has acquired a lot of media attention in recent years, and it has had a significant impact on the transport sector. This paper investigates the existing impact and potential of various forms of shared mobility, concentrating on the case study of Wanneroo, Western Australia. We adopted bibliometric analysis and visualization tools based on nearly 700 papers collected from the Scopus database to identify research clusters on shared mobility. Based on the clusters identified, we undertook a further content analysis to clarify the factors affecting the potential of different shared mobility modes. A specially designed questionnaire was applied for Wanneroo’s residents to explore their use of shared mobility, their future behaviour intentions, and their perspectives on the advantages and challenges of adoption. The empirical findings indicate that the majority of respondents who had used shared mobility options in the last 12 months belong to the low-mean-age group. The younger age group of participants also showed positive views on shared mobility and would consider using it in the future. Household size in terms of number of children did not make any impact on shared mobility options. Preference for shared mobility services is not related to income level. Bike sharing was less commonly used than the other forms of shared mobility

Efficient preparation and detection of microwave dressed-state qubits and qutrits with trapped ions

We demonstrate a method for preparing and detecting all eigenstates of a three-level microwave dressed system with a single trapped ion. The method significantly reduces the experimental complexity of gate operations with dressed-state qubits, as well as allowing all three of the dressed states to be prepared and detected, thereby providing access to a qutrit that is well protected from magnetic field noise. In addition, we demonstrate individual addressing of the clock transitions in two ions using a strong static magnetic field gradient, showing that our method can be used to prepare and detect microwave dressed states in a string of ions when performing multi-ion quantum operations with microwave and radio frequency fields. The individual addressability of clock transitions could also allow for the control of pairwise interaction strengths between arbitrary ions in a string using lasers

Creep behaviour of structured clays in triaxial stress space: theory and experimental investigation

This paper investigates the time-dependent behaviour of structured clays in triaxial stress space both theoretically and experimentally. A range of existing theoretical frameworks and phenomenological equations are reviewed and discussed in their ability to interpret the creep behaviour at different states in q:p′ stress space. New experimental results are presented for two structured clays subjected to complex loading conditions. Each test consists of a defined stress path with intermediate stages of creep. Considerable creep deformations were observed at all anisotropic effective stress conditions. Measured viscous deformations were observed to be related to the stress state, approaching stress path and degree of structure present in the soil. The incremental strain ratio, Δεs/Δεvol , measured during constant stress was found to rotate counter-clockwise as a result of drained shearing towards failure for all tests. The experiments also show that for very small stress increments, phenomenological and empirical relations incorrectly predict the development of creep strains with time

Estimating column diamters in jet-grouting processes

Jet grouting is widely used in geotechnical engineering for a variety of applications and is a well-proven technique. As with many techniques developed from a practical perspective, there is still scope for improvements both in construction practice and design. This paper focuses on one of the most crucial elements of quality control required with jet grouting operations, the diameter of the constructed column. First, the jet grouting method is explained and the main issues of the concept highlighted. A description follows of the techniques available for estimating column diameter, discussing their application and evaluation on site. There is a particular emphasis on two methods: inclined core drilling and a newly-developed thermic approach (Meinhard et al., 2010) both of which were implemented on two construction projects. Data from these case studies are reported and analysed extensively, in conjunction with influencing factors such as the ground conditions, to assess their effects on the achieved diameter. An empirical approach for evaluating the diameter of jet-grouted columns is developed based on various factors influencing their size such as monitor lifting speed and soil strength

On Visible Homelessness and the Micro-Aesthetics of Public Space

In this article, we investigate the circumstances that have produced the current municipal regulatory approach to homelessness in the City of Melbourne, Victoria, and the ways in which visibly homeless people are policed through a micro-aesthetics of their presence in public space, which involves the monitoring of their bodily demeanour and their physical possessions. Our study contributes to and draws from a range of debates, including studies of the governmental conjunction of poverty and crime, analysis of the co-implication of law and spatiality, research on the criminalisation of homelessness and homeless people, and the burgeoning criminological interest in the significance of the visual field for our understandings of crime and criminality. This article recounts how homelessness, public space and questions of aesthetics have recently coalesced in debates about the regulation of homelessness in the public space of Melbourne’s city centre. It approaches the issues through comparative consideration of genres of municipal management frameworks in other jurisdictions, detailed textual consideration of the Protocol on Homelessness in the City of Melbourne and an empirical study of visible homelessness in the public places of central Melbourne

Effects of Maternal Employment and Prematurity on Child Outcomes in Single Parent Families

Background Effects of maternal employment for preschool children vary based on specific characteristics of the mother’s employment, the family’s economic status, and the mother’s attitudes about employment. However, there is limited research on a growing group of children at developmental risk—those born prematurely and living in a single-parent family. Objective To examine the effects of maternal employment and prematurity on child cognition and behavior in single-parent families. Methods Sixty preterm and 61 full-term preschool children were recruited through NICU admission records and birth records. Data were collected with the Kaufmann Assessment Battery for Children, Peabody Picture Vocabulary Test, Child Behavior Checklist, Parenting Stress Index, and the Life History Calendar. Results Greater hours employed was related to higher achievement and mental processing scores only. Less discrepancy between actual and desired employment was related to higher achievement, mental processing, and language scores and lower behavior scores. Prematurity was not related to child cognitive and behavioral performance. Only the relationship between discrepancy and language remained after statistical control. Conclusions The concerns about negative effects of maternal employment on young children may be overstated, especially in low-income, single-mother families. These findings are especially important in the context of welfare reform

Digital health and inequalities in access to health services in Bangladesh: Mixed methods study

Background: Globally, the rapid growth of technology and its use as a development solution has generated much interest in digital health. In line with global trends, Bangladesh is also integrating technology into its health system to address disparities. Strong political endorsement and uptake of digital platforms by the government has influenced the rapid proliferation of such initiatives in the country. This paper aims to examine the implications of digital health on access to health care in Bangladesh, considering who uses electronic devices to access health information and services and why. Objective: This study aims to understand how access to health care and related information through electronic means (digital health) is affected by sociodemographic determinants (ie, age, gender, education, socioeconomic status, and personal and household ownership of mobile phones) in a semiurban community in Bangladesh. Methods: A cross-sectional survey of 854 households (between October 2013 and February 2014) and 20 focus group discussions (between February 2017 and March 2017) were conducted to understand (1) who owns electronic devices; (2) who, among the owners, uses these to access health information and services and why; (3) the awareness of electronic sources of health information; and (4) the role of intermediaries (family members or peers who helped to look for health information using electronic devices). Results: A total of 90.3% (771/854) of households (471/854, 55.2% of respondents) owned electronic devices, mostly mobile phones. Among these, 7.2% (34/471) used them to access health information or services. Middle-aged (35-54 years), female, less (or not) educated, and poorer people used these devices the least (α=.05, α is the level of significance). The lack of awareness, discomfort, differences with regular care-seeking habits, lack of understanding and skills, and proximity to a health facility were the main reasons for not using devices to access digital health. Conclusions: Although influenced by sociodemographic traits, access to digital health is not merely related to device ownership and technical skill. Rather, it is a combination of general health literacy, phone ownership, material resources, and technical skill as well as social recognition of health needs and inequity. This study’s findings should serve as a basis for better integrating technology within the health system and ensuring equitable access to health care

Pharmacokinetics of penicillin G in preterm and term neonates.

Group B streptococci are common causative agents of early-onset neonatal sepsis (EOS). Pharmacokinetic (PK) data for penicillin G have been described for extremely preterm neonates but poorly for late-preterm and term neonates. Thus, evidence-based dosing recommendations are lacking. We described PK of penicillin G in neonates with gestational age (GA) ≥32 weeks and postnatal age 90% for MICs ≤2 mg/L with doses of 25,000 IU/kg/q12h. In neonates, regardless of GA, PK parameters of penicillin G are similar. The dose of 25,000 IU/kg/q12h is suggested for treatment of group B streptococcal EOS diagnosed within the first 72 hours of life