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1 – 10 of 129John D. Salamone and Mercè Correa
Classical definitions of motivation typically involve two main components: direction and activation. Motivated behavior is directed toward or away from particular stimuli…
Abstract
Classical definitions of motivation typically involve two main components: direction and activation. Motivated behavior is directed toward or away from particular stimuli (i.e., appetitive and aversive motivation). Furthermore, activational aspects of motivation refer to the observation that motivated behavior is characterized by substantial activity, vigor, persistence, and exertion of effort in both the initiation and maintenance of behavior. Although separate neural systems direct organisms toward distinct motivational stimuli (e.g., food, water, sex), there appears to be a common circuitry regulating behavioral activation and the exertion of effort. Mesolimbic dopamine is one of the brain systems mediating activational aspects of motivation and exertion of effort. This system integrates aspects of motivation and motor control functions involved in the instigation of action. Research on the neurobiology of effort has contributed to our understanding of the pathophysiology of neurological and psychiatric disorders that are characterized by motivational dysfunction.
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C.R. Pickering, W.A. Craig, M.F. Barker, J. Cocker, P.C. Donohue and G. Vanrietvelde
Complex mixed metallurgy multilayers require a very robust dielectric to withstand shorting or blistering effects, together with high density for long‐term reliability in…
Abstract
Complex mixed metallurgy multilayers require a very robust dielectric to withstand shorting or blistering effects, together with high density for long‐term reliability in humid environments. The development and performance of a new multilayer dielectric which meets these needs is presented here. A dielectric frit chemistry has been developed with a view to eliminating short circuits and blistering induced by the proximity of dissimilar metallurgies on multiple refiring. Appropriate filler technology has also been developed to optimise dielectric density, toughness and laser‐trim properties. High density has yielded excellent HBT (High Bias Temperature) and HHBT (High Humidity Bias Test) performance. Data on multilayer circuit bowing are presented which take account of the interaction of conductor frit and the dielectric on firing. Silver conductor is employed in inner layers to optimise conductivity and cost. A new 1:3 PdAg conductor for termination of components and resistors also permits heavy Al wire bonding with good aged performance. 25 µm Au and 37 µm Al wire bonding is facilitated by gold conductor on dielectric. The laser trim characteristics of a new resistor series on dielectric are described. The materials system has been tested in a complex multilayer structure which, with the use of a new silver via fill conductor, resulted in defect‐free circuits with zero yield loss.
Since the 1994 regime change many South African public libraries have been destroyed by the communities they were serving which raises questions about how communities…
Abstract
Purpose
Since the 1994 regime change many South African public libraries have been destroyed by the communities they were serving which raises questions about how communities perceive these libraries. With the loss of activist library organizations, few insights are gained from activists or critical librarianship on how to respond. In this context, the chapter examines public library social inclusion and poverty alleviation initiatives, and government conditional grants to public libraries.
Methodology/approach
Using a transformative paradigm, a qualitative approach and thematic analysis, the chapter examines recent literature on public libraries and social inclusion, and local annual and parliamentary reports. A mini-survey yields case study material.
Findings
The findings augment the scarce store of recent evidence on South African public libraries. Most provinces had built new libraries, upgraded others, and installed information and communication infrastructure to enhance access. Problems included governance, fund wastage, and staffing. The libraries have great potential to improve their relevance for local communities.
Research limitations
The poor survey response rate and lack of a comprehensive national database on public libraries limits the research. Annual reports are uneven in comprehensiveness, making comparison difficult.
Practical implications
The chapter recommends (i) creating a national information system to monitor service delivery via the grants and enable rigorous investigation of their impact and (ii) increased government support for public library social inclusion initiatives.
Originality/value
First hand evidence from local librarians and official reports demonstrates the grants’ effect on public library promotion of social inclusion and shows what is possible in a situation of historical inequities.
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Cristina S. Judge and David McMenemy
This chapter introduces a model for school libraries in Scotland, based on best practices as identified in the literature, and on five case studies undertaken in schools…
Abstract
This chapter introduces a model for school libraries in Scotland, based on best practices as identified in the literature, and on five case studies undertaken in schools, two in the United States and three in Scotland. The research design was qualitative, and used grounded theory and multiple case study methods. The model represents an ideal set of circumstances for school libraries in Scotland, highlighting the interconnected web of influences that affect the success of a school library in meeting professional standards. These influences primarily fall in three areas: the school librarian, the school environment, and the professional support available to the librarian. The school librarian is the primary leader of the school library program, but factors in these other two areas can provide opportunities and barriers that can help or hinder the success of the library service. For instance, the findings suggest that school-based factors such as curriculum, scheduling, technology facilities, and staffing can have significant influence over the access the librarian has to teachers and students. Our model includes all three areas in describing a set of circumstances that would allow a school library program to thrive and meet the highest professional standards.
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Mark Piney, Diane Llewellyn, Rachel O'Hara, John Saunders, John Cocker, Kate Jones and David Fishwick
Exposure to isocyanates was the leading cause of occupational asthma in the UK. Motor vehicle repair (MVR) bodyshop paint sprayers were at greatest risk, despite…
Abstract
Purpose
Exposure to isocyanates was the leading cause of occupational asthma in the UK. Motor vehicle repair (MVR) bodyshop paint sprayers were at greatest risk, despite widespread use of air-fed breathing apparatus and ventilated booths. Most paint sprayers work in small and medium enterprises (SMEs). The purpose of the Health and Safety Executive (HSE) project, described in this paper, is to improve exposure control measures in at least 20 per cent of MVR bodyshops, and reduce the risk of occupational asthma. The paper aims to discuss this issue.
Design/methodology/approach
A three-stranded plan consisted of: Safety and Health Awareness Days (SHADs); workplace inspections; and third-party stakeholder communications. The impact of various parts of the project were evaluated.
Findings
Approximately 18 per cent of bodyshops in the UK attended one of 32 SHADs, following which over 90 per cent of delegates expressed an “intention to act” to improve exposure control measures. A local assessment showed that at least 50 per cent of bodyshops improved exposure control measures. An evaluation of 109 inspections found that enforcement action was taken at 40 per cent of visits. Third-party engagement produced a joint HSE-industry designed poster, new agreed guidance on spray booths and dissemination of SHAD material. Knowledge of booth clearance time has become widespread, and 85 per cent of booths now have pressure gauges. Biological monitoring data show that, post-SHAD, exposures were lower.
Originality/value
A sustained national project using clear, relevant, tested messages delivered via different routes, had a sector-wide impact in bodyshops. It is probable that the project has improved isocyanate exposure control in at least 20 per cent of bodyshops. The generic lessons could be applied to other widespread SME businesses.
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J.V. Manca, L. De Schepper, W. De Ceuninck, M. D'Olieslager, L.M. Stals, M.F. Barker, C.R. Pickering, W.A. Craig, E. Beyne and J. Roggen
In this paper, it is shown that the so‐called in‐situ electrical measurement technique is a valuable tool for understanding failure mechanisms in thick film dielectrics…
Abstract
In this paper, it is shown that the so‐called in‐situ electrical measurement technique is a valuable tool for understanding failure mechanisms in thick film dielectrics. The technique makes it possible to measure important electrical characteristics of thick film dielectric systems in the temperature range from room temperature up to 900°C. This information is essential to understand failure mechanisms and to optimise the system with respect to quality and reliability. Mainly two electrical properties have been investigated: (i) the electrical resistance of the dielectric as a function of temperature and (ii) the spontaneous electromotive force occurring at higher temperatures between two metal layers with the dielectric in between. A significant result of the work is the observation of a close correlation between the leakage current measured through the dielectric at elevated temperatures, and the ability of the dielectric to resist shorting and blistering effects during the preparation of circuits. Secondly, from in‐situ voltage measurements, it was confirmed that the mixed metallurgy system Au(bottom)‐dielectric‐Ag(top) acts at 850°C as a spontaneous battery, and the battery voltage (i.e., the spontaneous electromotive force) was measured. Depending on the type of dielectric, a battery voltage up to 200 mV between the two metal layers was observed. As a result of this spontaneous electromotive force, blistering occurs. The battery voltage was shown to be much smaller in unmixed metallurgy systems with Ag(bottom)‐dielectric‐Ag(top) or Au(bottom)‐dielectric‐Au(top). However, if an external voltage of 300 mV is applied to such a system during a temperature profile up to 850°C, blisters can also be induced. This shows unambiguously that blistering is a voltage driven effect.
Osvaldo J. Arenas, Emilie Leynia de la Jarrige and François Boone
The purpose of this paper is to share valuable information about low‐cost microwave circuit research with academic and industrial communities that work, or want to work…
Abstract
Purpose
The purpose of this paper is to share valuable information about low‐cost microwave circuit research with academic and industrial communities that work, or want to work, in this field.
Design/methodology/approach
Screen‐printing technology has been chosen as the fabrication method because of simplicity and low costs. Different materials and printing parameters were tested in four generations of microstrip lines. After obtaining a satisfactory fabrication method, passive microwave components were printed, assembled, characterized and modeled.
Findings
Results demonstrated that the proposed low‐cost method allows fabricating low loss microstrip lines (15.63×10−3 dB/mm at 10 GHz), filters, inductors, and capacitors that work well up to 12 GHz.
Research limitations/implications
Model accuracy of inductors and capacitors can be improved. The use of more precise calibration and de‐embedding techniques is necessary. More components can be fabricated and modeled to increase the flexibility and applicability of the proposed fabrication method.
Practical implications
The presented information can help limited budget companies and small educational institutions in electronics to fabricate microwave circuits at low costs. This is an excellent approach for students who want to learn how to make microwave frequency measurements and circuits without the need of expensive fabrication equipment and clean rooms.
Originality/value
The step‐by‐step fabrication method described in this paper allows fabricating different microwave components at low costs. The presentation of electrical models for each component completes the design‐fabrication cycle. As this information is gathered in a single source, it makes easier the incursion of new actors in the microwave field.
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