Effect of Mixture Composition on Relative Strength of Highly Flowable Underwater Concrete

Concrete used for underwater repair is often proportioned to spread readily into place and self-consolidate, and to develop high resistance to segregation and water dilution. An investigation was carried out to determine the effect of the dosage of antiwashout admixture, water-cementitious materials ratio (w/cm), and binder composition on the relative residual strength of highly flowable underwater concrete. Two types of antiwashout admixtures were used: a powdered welan gum at 0.07 and 0.15% by mass of binder, and a liquid-based cellulosic admixture employed at a high dosage of 1 to 1.65 L/100 kg of cementitious materials. The w/cms were set at 0.41 and 0.47 to secure adequate performance of underwater concrete for construction and repair. Four binder compositions were used: a Canadian Type 10 cement; a cement with 10% silica fume replacement; a cement with 50% replacement of granulated blast-furnace slag; and a ternary binder containing 6% silica fume and 20% Class F fly ash. Test results indicate that for a given washout mass loss and slump flow consistency, greater relative residual strength can be secured when the dosage of antiwashout admixture is increased, the w/cm is reduced, and a binary binder with 10% silica fume substitution or the ternary binder are employed. Such mixtures can develop relative residual compressive strengths of 85 and 80%, compared to mixtures cast in air, when the value of washout loss is limited to 4 and 6% for mixtures with slump flow values of 450 and 550 mm, respectively.

Factor markets in England before the Black Death

Modern English factor markets originated during the two centuries of active commercialization that preceded the Black Death. An active labour market was established by the late twelfth century. Evolution of a land market followed the legal reforms of the 1170s and 1180s, which created legally secure and defensible property rights in land. These rights stimulated growth of a capital market, since land became a security against which credit could be obtained. Nevertheless, none of these nascent factor markets functioned unconstrained and each became embedded in legal, tenurial, and institutional complexities and rigidities which it took later generations centuries to reform.

Synchrophasor Broadcast over Internet Protocol for Distributed Generator Synchronization

Synchronous islanded operation involves continuously holding an islanded power network in virtual synchronism with the main power system to aid paralleling and avoid potentially damaging out-of-synchronism reclosure. This requires phase control of the generators in the island and the transmission of a reference signal from a secure location on the main power system. Global positioning system (GPS) time-synchronized phasor measurements transmitted via an Internet protocol (IP) are used for the reference signal. However, while offering low cost and a readily available solution for distribution networks, IP communications have variable latency and are susceptible to packet loss, which can make time-critical control applications difficult. This paper investigates the ability of the phase-control system to tolerate communications latency. Phasor measurement conditioning algorithms that can tolerate latency are used in the phase-control loop of a 50-kVA diesel generator. © 2010 IEEE.

Investigating the Interhemisphere 14C Offset in the 1st Millennium AD and Assessment of Laboratory Bias and Calibration Errors

Past measurements of the radiocarbon interhemispheric offset have been restricted to relatively young samples because of a lack of older dendrochronologically secure Southern Hemisphere tree-ring chronologies. The Southern Hemisphere calibration data set SHCal04 earlier than AD 950 utilizes a variable interhemispheric offset derived from measured 2nd millennium AD Southern Hemisphere/Northern Hemisphere sample pairs with the assumption of stable Holocene ocean/ atmosphere interactions. This study extends the range of measured interhemispheric offset values with 20 decadal New Zealand kauri and Irish oak sample pairs from 3 selected time intervals in the 1st millennium AD and is part of a larger program to obtain high-precision Southern Hemisphere 14C data continuously back to 200 BC. We found an average interhemispheric offset of 35 ± 6 yr, which although consistent with previously published 2nd millennium AD measurements, is lower than the offset of 55–58 yr utilized in SHCal04. We concur with McCormac et al. (2008) that the IntCal04 measurement for AD 775 may indeed be slightly too old but also suggest the McCormac results appear excessively young for the interval AD 755–785. In addition, we raise the issue of laboratory bias and calibration errors, and encourage all laboratories to check their consistency with appropriate calibration curves and invest more effort into improving the accuracy of those curves.

Site formation processes in caves: the Holocene sediments of the Haua Fteah, Cyrenaica, Libya.

Caves have yielded some of the most globally important archaeological sequences, but often their interpretation has suffered from assumptions about cave sedimentary processes. Caves contain distinctive sedimentary environments: this has major implications for the understanding of contained archaeological materials. This paper describes and analyses the Holocene sediments in the Haua Fteah, a sequence regarded as essentially continuous by the original excavator. 50 years after it was first excavated, the Haua’s Epipalaeolithic to post-Classical chronological range and rich finds make it still the key Holocene archaeological site in North Africa. The reassessment shows, however, that the sequence is strongly discontinuous and this has major implications for the reinterpretation of the site, as the highlyresolved archaeological record is thus likely to reflect a series of brief occupations, rather than continuous human activity. As with many caves, the sedimentary record in the Haua Fteah is an extremely sensitive indicator of environments and processes in the wider landscape. Secure understanding of sedimentary process, from analysis of the highly individual records found in caves, is essential for full understanding of their contained archaeology.

‘Child Care (Amendment) Bill 2009—An attempt to arbitrate on a system’s logic.’

The Child Care (Amendment) Bill was passed by the Seanad on 6th May 2010 and will shortly be enacted as legislation as the Child Care (Amendment) Act, 2010. The Bill, consisting of six Parts amends existing legislation relating to secure or ‘special care’ and makes some further amendments to the Child Care Act, 1991. The Act also provides for the dissolution of the Children Acts Advisory Board, a statutory body established in 2003, whose function was to advise the Minister on policy relating to specialist residential services (specifically Special Care Units) . This article examines the provisions of the Child Care Bill (2009) setting these in the context of current policy and previous legislation. It outlines that while the legislation outlines a detailed process for the application and administration of Special Care Orders, the provisions are weakened by the removal of external oversight mechanisms and the limitations placed on the role of the Guardian ad Litem.

Viscoelastic Material Models of Polypropylene for Thermoforming Applications

Polypropylene (PP), a semi-crystalline material, is typically solid phase thermoformed at temperatures associated with crystalline melting, generally in the 150° to 160°Celsius range. In this very narrow thermoforming window the mechanical properties of the material rapidly decline with increasing temperature and these large changes in properties make Polypropylene one of the more difficult materials to process by thermoforming. Measurement of the deformation behaviour of a material under processing conditions is particularly important for accurate numerical modelling of thermoforming processes. This paper presents the findings of a study into the physical behaviour of industrial thermoforming grades of Polypropylene. Practical tests were performed using custom built materials testing machines and thermoforming equipment at Queen′s University Belfast. Numerical simulations of these processes were constructed to replicate thermoforming conditions using industry standard Finite Element Analysis software, namely ABAQUS and custom built user material model subroutines. Several variant constitutive models were used to represent the behaviour of the Polypropylene materials during processing. This included a range of phenomenological, rheological and blended constitutive models. The paper discusses approaches to modelling industrial plug-assisted thermoforming operations using Finite Element Analysis techniques and the range of material models constructed and investigated. It directly compares practical results to numerical predictions. The paper culminates discussing the learning points from using Finite Element Methods to simulate the plug-assisted thermoforming of Polypropylene, which presents complex contact, thermal, friction and material modelling challenges. The paper makes recommendations as to the relative importance of these inputs in general terms with regard to correlating to experimentally gathered data. The paper also presents recommendations as to the approaches to be taken to secure simulation predictions of improved accuracy.

‘Government(ality) By Experts: Human Rights as Governance’

The suggestion that the general economy of power in our societies is becoming a domain of security was made by Michel Foucault in the late 1970s. This paper takes inspiration from Foucault?s work to interpret human rights as technologies of governmentality, which make possible the safe and secure society. I examine, by way of illustration, the site of the European Union and its use of new modes of governance to regulate rights discourse – in particular via the emergence of a new Fundamental Rights Agency. „Governance? in the EU is constructed in an apolitical way, as a departure from traditional legal and juridical methods of governing. I argue, however, that the features of governance represent technologies of government(ality), a new form of both being governed through rights and of governing rights. The governance feature that this article is most interested in is experts. The article aims to show, first and foremost, how rights operate as technologies of governmentality via a new relation to expertise. Second, it considers the significant implications that this reading of rights has for rights as a regulatory and normalising discourse. Finally, it highlights how the overlap between rights and governance discourses can be problematic because (as the EU model illustrates) governance conceals the power relations of governmentality, allowing, for instance, the unproblematic representation of the EU as an international human rights actor

Putting a Price on Prisoner Release: The History of Bail and the Future of Parole

In this article, we argue that the history of bail foretells the future of parole. Under a plancalled the Conditional Post-Conviction Release Bond Act (recently passed into law inthree states), US prisoners can secure early release only after posting ‘post-convictionbail’. As with pre-trial bail, the fledgling model would require prisoners to pay a percent-age of the bail amount to secure their release under the contractual responsibility of acommercial bail agency. If release conditions are breached, bounty hunters are legallyempowered to seize and return the parolee to prison. Our inquiry outlines the origins of this post-conviction bond plan and the research upon which it is based. Drawing on the‘new penology’ framework, we identify several underlying factors that make for a ripeadvocacy environment and set the stage for widespread state-level adoption of this planin the near future. Post-conviction bail fits squarely within the growing policy trendstoward privatization, managerialism, and actuarial justice. Most importantly, though,advocates have the benefit of precedent on their side, as most US states have longrelied on a system of commercial bail bonding and private bounty hunting to manageconditional pretrial release.

A strategic review of electricity systems models

Electricity systems models are software tools used to manage electricity demand and the electricity systems, to trade electricity and for generation expansion planning purposes. Various portfolios and scenarios are modelled in order to compare the effects of decision making in policy and on business development plans in electricity systems so as to best advise governments and industry on the least cost economic and environmental approach to electricity supply, while maintaining a secure supply of sufficient quality electricity. The modelling techniques developed to study vertically integrated state monopolies are now applied in liberalised markets where the issues and constraints are more complex. This paper reviews the changing role of electricity systems modelling in a strategic manner, focussing on the modelling response to key developments, the move away from monopoly towards liberalised market regimes and the increasing complexity brought about by policy targets for renewable energy and emissions. The paper provides an overview of electricity systems modelling techniques, discusses a number of key proprietary electricity systems models used in the USA and Europe and provides an information resource to the electricity analyst not currently readily available in the literature on the choice of model to investigate different aspects of the electricity system.

Dynamic global security-aware synthesis using System-C

A dynamic global security-aware synthesis flow using the SystemC language is presented. SystemC security models are first specified at the system or behavioural level using a library of SystemC behavioural descriptions which provide for the reuse and extension of security modules. At the core of the system is incorporated a global security-aware scheduling algorithm which allows for scheduling to a mixture of components of varying security level. The output from the scheduler is translated into annotated nets which are subsequently passed to allocation, optimisation and mapping tools for mapping into circuits. The synthesised circuits incorporate asynchronous secure power-balanced and fault-protected components. Results show that the approach offers robust implementations and efficient security/area trade-offs leading to significant improvements in turnover.

Treatment Foster Care for improving outcomes in children and young people (Review)

Background: Treatment foster care (TFC) is a foster family-based intervention that aims to provide young people (and, where appropriate, their families) with a tailored programme designed to effect positive changes in their lives. TFC was designed specifically to cater for the needs of children whose difficulties or circumstances place them at risk of multiple placements and/or more restrictive placements such as hospital or secure residential or youth justice settings.

Objectives: To assess the impact of TFC on psychosocial and behavioural outcomes, delinquency, placement stability, and discharge status for children and adolescents who require out-of-home placement.

Search methods: We searched the Cochrane Controlled Trials Register (CENTRAL) 2006 (Issue 4), MEDLINE (1966 to January 2007), CINAHL (1982 to December 2006), PsycINFO (1872 to January 2007), ASSIA (1987 to January 2007), LILACS (1982 to January 2007), ERIC (1966 to January 2007), Sociological Abstracts (1963 to January 2007), and the National Research Register 2006 (Issue 4).

Selection criteria: Included studies were randomised controlled trials investigating the effectiveness of TFC with children and young people up to the age of 18 who, for reasons of severe medical, social, psychological and behavioural problems, were placed in out of home care in restrictive settings (e.g. secure residential care, psychiatric hospital) or at risk of placement in such settings.

Data collection and analysis: Titles and abstracts identified in the search were independently assessed for eligibility by the two authors (GM and WT) who also extracted and entered into REVMAN. Date were synthesised on the few occasions where this was possible. Results are presented in tabular, graphical (forest plots) and textual form.

Main results: Five studies including 390 participants were included in this review. Data suggest that treatment foster care may be a useful intervention for children and young people with complex emotional, psychological and behavioural need, who are at risk of placements in nonfamily settings that restrict their liberty and opportunities for social inclusion.

Authors’ conclusions: Although the inclusion criteria for this systematic review set a study design threshold higher than that of previous reviews, the results mirror those of earlier reviews but also highlights the tendency of the perceived effectiveness of popular interventions to outstrip their evidence base. Whilst the results of individual studies generally indicate that TFC is a promising intervention for children and youth experiencing mental health problems, behavioural problems or problems of delinquency, the evidence base is less robust than that usually reported.The Cochrane Database of Systematic Reviews is a peer reviewed, international journal, published electronically each month. The 2010 Inpact Factor for the Cochrane Database of Systematic Reviews was 6.185.The CDSR is now ranked in the top 10 of the 151 in the Medicine, General & Internal category.