Gaining Confidence in Software Inspection Using a Bayesian Belief Model

In this paper I describe how confidence in a software inspection can be obtained through calculating an estimate of its effectiveness. The method uses a Bayesian Belief Network to model the software inspection process and calculates the inference on how effective a particular inspection was. This technique was selected as it provides a means of initialising the model with inspectors' experience and has the ability to learn and optimise performance. This technique provides answers to some of the questions and limitations raised by current models used to predict inspection effectiveness. The application of the model to a major software project is discussed, covering the initial practitioner survey, model initialisation, model calibration and verification results obtained.     

Modular Reconfigurable Robots in Space Applications

Robots used for tasks in space have strict requirements. Modular reconfigurable robots have a variety of attributes that are well suited to these conditions, including: serving as many different tools at once (saving weight), packing into compressed forms (saving space) and having high levels of redundancy (increasing robustness). In addition, self-reconfigurable systems can self-repair and adapt to changing or unanticipated conditions. This paper will describe such a self-reconfigurable modular robot: PolyBot. PolyBot has significant potential in the space manipulation and surface mobility class of applications for space.     

A Method for Conceptualising Legal Domains. An Example from the Dutch Unemployment Benefits Act

There has been much talk of the need to build intermediate models of the expertise required preparatory to constructing a knowledge-based system in the legal domain. Such models offer advantages for verification, validation, maintenance and reuse. As yet, however, few such models have been reported at a useful level of detail. In this paper we describe a method for conceptualising legal domains as well as its application to a substantial fragment of the Dutch Unemployment Benefits Act (DUBA).We first discuss the intermediate models (called expertise models), then present a three-stage method for their construction, drawing on the CommonKADS work in knowledge acquisition, conceptual models of statute law, and the KANT method of knowledge analysis. Subsequently, we describe how these techniques were applied to the DUBA, and provide detailed examples of the resulting model. Finally, conclusions on the framework and guidelines are given as well as means of recording and presenting the various design choices.     

Silicon-based miniature sensor for electrical tomography

The paper describes the fabrication of a novel miniature sensor for electrical tomography. The sensor comprises a number of copper electrodes that are fabricated around a small hole that is etched through a silicon wafer. Copper electrodes are electroplated to fill channels that are formed in thick photo-resist on top of the silicon wafer. Electrodes with a thickness of 60 μm, surrounding a hole of diameter 300 μm, have been realised. Initial measurements have been made using a commercial LCR meter applied to an eight-electrode sensor and images of a 80 μm diameter wire have been obtained. Future work will consider the integration of measurement circuitry alongside the electrodes in order to reduce parasitic capacitances.     

Calibration of AFM cantilever spring constants

In this paper we present two simple, reliable and readily applicable methods for calibrating cantilevers and measuring the thickness of thin gold films. The spring constant calibration requires knowledge of the Young's modulus, density of the cantilever and resonant frequency. The thickness of thin gold layers was determined by measuring changes in the resonant frequency and Q-factor of beam shaped AFM cantilevers before and after coating.The techniques for measuring the spring constant and thin film thickness provide accuracy on the order of 10-15%.     

Assessing the reliability of the M5-120 on Amazon’s mechanical Turk

Amazon’s online service, Mechanical Turk (MTurk) has become a popular option for data collection among social scientists. Early work (Buhrmester, Kwang, & Gosling, 2011) indicated that data collection through MTurk was faster and less expensive than traditional collection methods (undergraduate human subject pool), as well as being reliable when administered at different dates. Building on their work, we sought to extend this investigation of reliability to a larger measure. For the current research we chose a 120-item measure of personality. After collecting data through MTurk, it was determined that our MTurk sample had strong test–retest reliability, indicating that they did not significantly change between administration dates.     

Prospects for the incorporation of cobalt into α-Fe2O3 nanorods during hydrothermal synthesis

A feasibility study on the incorporation of cobalt into α-Fe₂O₃ nanorods (NRs) during hydrothermal synthesis (HS) is presented as a function of FeCl₃ and CoCl₂ concentration, phosphate surfactant concentration and pH value, with samples assessed using X-ray diffractometry, transmission electron microscopy, selected area electron diffraction and energy dispersive X-ray analysis. No evidence was found for the incorporation of cobalt into α-Fe₂O₃ NRs at low pH, whilst synthesis at intermediate and high pH values favoured the formation of CoFe₂O₄ NPs. The critical role of pH value over the precipitation, size and phase purity of the nanostructured reaction products is emphasised. At pH ~2, large, well crystalline α-Fe₂O₃ nanoparticles (NPs) and NRs were grown from FeCl₃ solution in the absence and presence of phosphate, respectively, whilst no evidence was found for Co precipitation or incorporation in α-Fe₂O₃ following HS in the presence of CoCl₂. At pH ~8, smaller α-Fe₂O₃ NPs, as well as Co₃O₄ and CoFe₂O₄ NPs were synthesised from FeCl₃, CoCl₂, or a mixture thereof. HS at pH ~12 produced a mixture of larger CoFe₂O₄ NPs and α-Fe₂O₃ NPs depending on the Fe:Co molar ratio. The formation of intermediate metastable (oxy)hydroxide phases is considered pH dependent, providing for a variety of different reaction pathways. Further, inclusion of preformed Co₃O₄ and CoFe₂O₄ NPs to the FeCl₃ solution at pH ~2 in the presence of phosphate surfactant resulted in the synthesis of α-Fe₂O₃ NRs with residual Co₃O₄ and CoFe₂O₄ NPs attached to their surfaces. The CoFe₂O₄ NPs encouraged local dissolution leading to the formation of α-Fe₂O₃ NR surface corrugations.     

Domestic demand-side response with heat pumps: controls and tariffs

ABSTRACT

Electric heat pumps feature prominently in projected energy transitions in the UK and elsewhere. Owing to their high electricity consumption, heat pumps are viewed as important targets for demand-side response (DSR). Findings are presented from a field trial of a new control system that aims to optimize heat pump performance, including under time-varying tariff conditions. The trial involved monitoring 76 properties with heat pumps, but without dedicated heat storage; 31 of these received the control system. Interviews were conducted with a subsample of 12 participants. The controller successfully evened out electricity demand over the day (reducing the evening peak), but this was associated with increased late night and daytime temperatures. Interview participants reported some disturbance owing to overnight heating and noise, as well as usability issues with the controller interface and hardware. These issues present risks to the future acceptability of such systems. While the system delivered short-term demand reductions successfully, longer-term demand shifting risked causing unacceptable disturbance to occupants. Future control systems could overcome some of the issues identified in this pioneering trial through more effective zoning, using temperature caps or installing dedicated heat storage, but these may either limit the available flexibility or be challenging to achieve.