Social norms and household time allocation

Economic theories of the household predict that increases in female relative human capital lead to decreases in female housework time. However, longitudinal and cross-sectional evidence seems to contradict this implication. Women's share of home time fails to decrease despite increases in women's relative earnings. The literature has proposed social norms on the household division of labor as an alternative explanation. We use the 2002-2003 Spanish Time Use Survey (STUS) to explore the presence of social norms associated with the household division of housework and childcare. First, we observe that wives who earn more than their husbands still do more than 50% of the housework and childcare. Second, we find that a woman's relative share of housework decreases as her relative earnings increase, but only up to the point where she earns the same as her husband. Finally, independently of the definition of childcare, the relative time devoted to childcare does not vary with spouses' relative earnings. All these findings suggest that social norms may be an important factor in the division of household time.Household production; intrahousehold allocation; time allocation; social norms;

Hydrogen generation by photocatalysis with BiVO

The aim of this work was to study the enhancement in photocatalytic hydrogen production by using BiVO combined with Si solar cells.2021/202

Quality Issues in Global Software Development

The most advantageous features of Global Software Development (GSD) are its cost saving benefits and the easily availability of resources. Also the technological advancement especially in Information and Communication Technology (ICT) makes GSD a common practice in software industry. But GSD is also facing a lot of challenges. Maintaining quality in software development processes and products in GSD environments is one of the major challenges. This paper presents a survey on the challenges and factors which impact on the quality of the\ud products in GSD environments. This report identifies that most of the factors which affect the quality of software product appear as part of two major challenges: requirements and coordination. We further demonstrate that how these two challenges are affected by several factors. Finally, we present the possible solution to reduce the complexity of those various factors

Modelling focused electron beam induced deposition beyond Langmuir adsorption

The continuum model of focused electron beam induced deposition (FEBID) is generalized to account for multilayer adsorption processes. Two types of adsorption energies, describing both physisorption and spontaneous chemisorption, are included. Steady state solutions under no diffusion are investigated and compared for a wide range of conditions. The different growth regimes observed are fully explained by relative changes in FEBID characteristic frequencies. Additionally, we present a set of FEBID frequency maps where growth rate and surface coverage are plotted as a function of characteristic timescales. From analyzing Langmuir, as well as homogeneous and heterogeneous multilayer maps, we infer that three types of growth regimes are possible for FEBID under no diffusion, resulting into four types of adsorption isotherms. We propose the use of these maps as a powerful tool for the analysis of FEBID processes.This research was funded by an EPSRC Early Career Fellowship EP/M008517/1 and a Winton Fellowship. This work was conducted within the framework of the COST Action CM1301 (CELINA). DSH acknowledges funding from a Girton College Pfeiffer Scholarship

Frequency selective surfaces for Terahertz applications

This thesis presents both theoretical and experimental investigations of the performance and capabilities of frequency selective surfaces (FSS) applied at THz frequencies. The aim is to explore and extend the use of FSS, traditionally limited to microwave frequencies, towards the THz regime of the spectrum, where interesting applications such as imaging, sensing and communications exist. The contribution of this work lies in three main areas within the scope of THz FSS, namely, performance, prototyping and applications. Unlike microwave FSS where extensive research has been performed to evaluate the performance of different FSS designs, particular problems arise at THz frequencies, significantly, the ohmic losses. While a few notable studies can be found on the issue of ohmic losses, part of this thesis investigates, for the first time, the power dissipation due to the presence of both ohmic and dielectric losses, in relation to the power stored in the vicinity of the FSS, the currents induced in the elements of the array and the array’s terminal impedance. By doing so, a better understanding of the performance of THz FSS has been given in terms of their quality factor, allowing for design guidelines previously unavailable. In order to demonstrate multiband operation experimentally, a novel fabrication process has been designed and developed to manufacture capacitive or dipole-based THz FSS on a dielectric layer. Dry deep-reactive ion etching has been employed in order to avoid the use of wet etching to provide better control of etch characteristics. Various FSS operating around 15THz have been demonstrated experimentally. In addition, THz FSS have been investigated theoretically in the realm of three different applications, namely, multiband operation, sensing capability and reconfigurability. Multiband characteristics using single-screen FSS have been achieved by perturbed dipole FSS exhibiting up to four resonances due to the excitation of even and odd current modes. After studying the near-fields in perturbed FSS, it has been found that this type of FSS represent a very attractive candidate for sensing applications due to the revealed near-field enhancement phenomena related to the excitation of the odd mode, where currents flow in opposite directions. Finally, a novel tunability approach to reach frequency reconfigurability by varying the near-field coupling between two closely spaced layers in a dual-layer configuration has been proposed. A MEMS movable four-arm membrane has been suggested to vary the distance between the two layers mechanically, leading to the frequency tuning effect. This approach has been shown to be particularly suitable for THz frequencies, and has been applied to demonstrate theoretically tunable FSS and other periodic structures, such as artificial magnetic conductors and dielectric gratings