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Evidence of 3D strain gradients associated with tin whisker growth

We have used Differential Aperture X-ray Microscopy (DAXM) to measure grain orientations and deviatoric elastic strains in 3D around a tin whisker. The results show strain gradients through the depth of the tin coating, revealing a higher strain deeper in the Sn layer. These higher strains are explained by the volume change occurring during growth of the intermetallic phase Cu6Sn5 at the interface

Lighting Control Systems to Save Energy in the non-Residential Sector : State-of-the-art, Field Studies, and Simulations

This thesis examines the energy-saving potential for lighting when using traditional indoor LCSs in non-residential buildings. In the study, an overarching theoretical framework is used that distinguishes between energy efficiency and energy saving, as well as between energy use for lighting and functional illumination. This framework also includes the hypothesis that user acceptance is a determin

Numerical simulations of flow structure and turbulent heat transfer in a square ribbed channel with varying rib pitch ratio

In the fast development of advanced gas turbines with increasing output power, the inlet temperature is accordingly increased. Traditional cooling techniques failed to deal with such situations; however, new cooling techniques incorporating ribbed microchannels with higher capability of heat removal are required. In the present research, a square ribbed channel with various rib pitch ratios is des

Resistance to activated protein C, highly prevalent amongst users of oral contraceptives with venous thromboembolism

OBJECTIVE: Inherited resistance to activated protein C (APC resistance), which is caused by a single point mutation in the factor V gene, is a frequent risk factor for venous thromboembolism. The aim of this study was to determine the prevalence of APC resistance and other coagulation disorders in fertile women with venous thromboembolism and also the risk factors these women had been exposed to i

Feedback for increased robustness of forwarding graphs in the cloud

Cloud computing technology provides the means to share physical resources among multiple users and data center tenants by exposing them as virtual resources. There is a strong industrial drive to use similar technology and concepts to provide timing sensitive services. One such domain is a chain of connected virtual network functions. This allows the capacity of each function to be scaled up and d

Enhanced extraction of flavonoids from Odontonema strictum leaves with antioxidant activity using supercritical carbon dioxide fluid combined with ethanol

Flavonoids were extracted from Odontonema strictum leaves by supercritical carbon dioxide, with ethanol. The effect of three independents variables (time, pressure and temperature) on the Total Flavonoid Content (TFC) were optimized by factorial investigation. The TFC and flavonoid recovery varies respectively from 99.33 to 247.78 mg/g of dried extract and 10.68–18.92 mg/g of dried leaves powder,

Liquid-liquid flow patterns and slug hydrodynamics in square microchannels of cross-shaped junctions

Flow patterns for water-butanol, water-toluene, water-hexane, water-oil and water/glycerol (weight ratio 60:40) mixture-oil two-phase flows were visualized in the cross-shaped junctions of three square glass microchannels with hydraulic diameters of 200 µm, 400 µm and 600 µm. The aqueous phase is the continuous phase contacting the channel walls while the organic phase is the dispersed phase in th

Bi-directional algebraic graphic statics

A pre-existing algebraic graphic statics method is extended to allow for interactive manipulations of the force diagram, from which an updated form diagram is determined. Newton's method is used to solve a set of non-linear equations, and the required Jacobian matrix is derived. Additional geometric constraints on the form diagram are introduced, and methods for improving the robustness of the met

Humidity sensing in insects — from ecology to neural processing

Humidity is an omnipresent climatic factor that influences the fitness, reproductive behavior and geographic distribution of animals. Insects in particular use humidity cues to navigate the environment. Although the sensory neurons of this elusive sense were first described more than fifty years ago, the transduction mechanism of humidity sensing (hygrosensation) remains unknown. Recent work has u