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21.
Councils and social housing organisations are looking to retrofit as a way to make their housing more energy efficient. Previous studies on energy use in social housing have generally focussed on the technological aspects (such as the potential savings possible by retrofitting this class of housing across the UK) or have involved one‐off interventions or measures. During a 2‐year period, we worked with previously homeless people to reduce their energy consumption. The 32 participants lived in small blocks of flats (owned by a social housing organisation) that underwent retrofitting with air source heat pumps. We ran a three‐phase tenant engagement programme to compare a range of approaches aimed at energy reduction. It was found that education, social norms and self‐awareness are all key components when it comes to initiating environmentally responsible behaviours. The three approaches complemented each other, and these ought to be considered alongside technology provision if the aim is to reduce energy consumption. A number of reflections on the implementation of medium‐term tenant engagement programmes are also presented. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
22.
The thermal expansion and magnetic behaviors of divalent, alkaline‐doped lanthanum ferrites (La0.9M0.1FeO3, M=Ca, Sr, Ba) were assessed using a combination of dilatometry, magnetometry, time‐of‐flight neutron diffraction, and high‐temperature X‐ray diffraction. Néel temperatures were determined through vibrating sample magnetometry and correlated well with changes in thermal expansion behavior observed during both dilatometry and X‐ray diffraction. The Néel temperatures observed for pure, Ca‐doped, Sr‐doped, and Ba‐doped lanthanum ferrites were 471°C, 351°C, 465°C, and 466°C, respectively. The effect of divalent substitutions on the magnetic behavior are attributed to charge compensation mechanisms and structural changes in the material.  相似文献   
23.
We demonstrate a pulsed ytterbium-doped fiber master-oscillator power amplifier source at 1060 nm producing over 300 W of average power in 20-ps pulses at 1-GHz repetition rate. The pulses generated by a gain-switched diode were compressed by a chirped fiber Bragg grating and amplified without any distortion with excellent spectral quality. This fiber master oscillator power amplifier system offers versatility and potential for further power scaling.  相似文献   
24.
The free vibration analysis of sandwich panels with a core that is flexible and compliant in the vertical direction and with temperature-dependent mechanical properties is presented in two parts. The first part presents the mathematical formulation while the second deals numerically with the effects of the degrading properties of the core on the free vibration response. The analysis is based on the high-order sandwich panel theory approach (HSAPT), and the equations of motions along with the appropriate boundary conditions are derived using the Hamilton’s principle. The study investigates the role of increasing temperature, through the degradation of the mechanical properties of the core, on the free vibration response of structural sandwich panels. The mathematical formulation uses two types of computational models. At first, following the HSAPT approach, the unknowns include the displacements of the face sheets as well as the shear stress in the core. Secondly, it is assumed that the through-thickness distributions of the vertical and horizontal core displacements can be represented as polynomials, following the results of the HSAPT static case, and the effect of the variable mechanical properties are implemented directly.  相似文献   
25.
Performances of SAS-super-180 air sampler and settle plates were investigated for the assessment of airborne fungal food contamination. Air samples were taken from processing rooms of a dry-cured production facility and outdoors. Fungal colonies and numbers of species were counted and compared. Quantitatively, the air sampler showed higher numbers of species and mean CFU/plate compared to settle plates. Qualitatively, the two methods showed similar dominating fungal genera and species associated with dry-cured meat products. The study showed settle plates could provide important qualitative information for food processing plants where airborne fungi associated with food products are the targets.  相似文献   
26.
Piezoelectric thick films have increasing interest due to the potential high sensitivity and actuation force for MEMS sensors and actuators. The screen printing technique is a promising deposition technique for realizing piezoelectric thick films in the thickness range from 10–100 μm. In this work integration of a screen printed piezoelectric PZT thick film with silicon MEMS technology is shown. A high bandwidth triaxial accelerometer has been designed, fabricated and characterized. The voltage sensitivity is 0.31 mV/g in the vertical direction, 0.062 mV/g in the horizontal direction and the first mode resonance frequency is 11 kHz. A Finite Element Method (FEM) model is used to validate the measured sensitivity and resonance frequency. Good agreement between the model and the measurements is seen.  相似文献   
27.
Die Dynamik der Technikentwicklung in den vergangenen Jahren konfrontiert Datenschützer immer wieder aufs Neue mit Risiken für die Privatsph?re der Betroffenen — und es sieht so aus, als ob sich dies in den n?chsten Jahren und Jahrzehnten nicht ?ndern wird. Konzepte für einen lebenslangen Datenschutz erfordern ein Umdenken vom kurzatmigen Systementwurf zu langfristigen und zukunftsf?higen Planungen.  相似文献   
28.
Conventional Doppler methods for blood velocity estimation only estimate the velocity component along the ultrasound beam direction. This implies that a Doppler angle under examination close to 90° results in unreliable information about the true blood direction and blood velocity. The novel method transverse oscillation (TO), which combines estimates of the axial and the transverse velocity components in the scan plane, makes it possible to estimate the vector velocity of the blood regardless of the Doppler angle. The present study evaluates the TO method with magnetic resonance phase contrast angiography (MRA) by comparing in vivo measurements of stroke volume. Eleven healthy volunteers were included in this prospective study. From the obtained data sets recorded with the 2 modalities, vector velocity sequences were constructed and stroke volume calculated. Angle of insonation was approximately 90° for TO measurements. The correlation between the stroke volume estimated by TO and MRA was 0.91 (p < 0.01) with the equation for the line of regression: MRA = 1.1?TO-0.4. A Bland-Altman plot was additionally constructed where the mean difference was 0.2 ml with limits of agreement at ?1.4 ml and 1.9 ml. The results indicate that reliable vector velocity estimates can be obtained in vivo using the presented angle-independent 2-D vector velocity method. The TO method can be a useful alternative to conventional Doppler systems by avoiding the angle artifact, thus giving quantitative velocity information.  相似文献   
29.
30.
Biomass is a renewable resource from which a broad variety of commodities can be produced. However, the resource is scarce and must be used with care to avoid depleting future stock possibilities. Flexibility and efficiency in production are key characteristics for biomass conversion technologies in future energy systems. Thermal gasification of biomass is proved throughout this article to be both highly flexible and efficient if used optimally. Cogeneration processes with production of heat-and-power, heat-power-and-fuel or heat-power-and-fertilizer are described and compared. The following gasification platforms are included in the assessment: The Harboøre up draft gasifier with gas engine, the Güssing FICFB gasifier with gas engine or PDU, the LT-CFB gasifier with steam cycle and nutrient recycling and finally the TwoStage down draft gasifier with gas engine, micro gas turbine (MGT), SOFC, SOFC/MGT or catalytic fuel synthesis.  相似文献   
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