The Quantum Socket: Three-Dimensional Wiring for Extensible Quantum Computing

Quantum computing architectures are on the verge of scalability, a key requirement for the implementation of a universal quantum computer. The next stage in this quest is the realization of quantum error correction codes, which will mitigate the impact of faulty quantum information on a quantum computer. Architectures with ten or more quantum bits (qubits) have been realized using trapped ions and superconducting circuits. While these implementations are potentially scalable, true scalability will require systems engineering to combine quantum and classical hardware. One technology demanding imminent efforts is the realization of a suitable wiring method for the control and measurement of a large number of qubits. In this work, we introduce an interconnect solution for solid-state qubits: The quantum socket. The quantum socket fully exploits the third dimension to connect classical electronics to qubits with higher density and better performance than two-dimensional methods based on wire bonding. The quantum socket is based on spring-mounted micro wires the three-dimensional wires that push directly on a micro-fabricated chip, making electrical contact. A small wire cross section (~1 mmm), nearly non-magnetic components, and functionality at low temperatures make the quantum socket ideal to operate solid-state qubits. The wires have a coaxial geometry and operate over a frequency range from DC to 8 GHz, with a contact resistance of ~150 mohm, an impedance mismatch of ~10 ohm, and minimal crosstalk. As a proof of principle, we fabricated and used a quantum socket to measure superconducting resonators at a temperature of ~10 mK.Comment: Main: 31 pages, 19 figs., 8 tables, 8 apps.; suppl.: 4 pages, 5 figs. (HiRes figs. and movies on request). Submitte

Validation of a simplified micromodel for analysis of infilled RC frames exposed to cyclic lateral loads

An RC frame structure with masonry infill walls (‘‘framed-masonry’’) exposed to lateral loads acts as a composite structure. Numerical simulation of framed-masonry is difficult and generally unreliable due to many difficulties and uncertainties in its modelling. In this paper, we reviewed the usability of an advanced non-linear FEM computer program to accurately predict the behaviour of framed-masonry elements when exposed to cyclic lateral loading. Numerical results are validated against the test results of framedmasonry specimens, with and without openings. Initial simplified micromodels were calibrated by adjustment of the input parameters within the physically justifiable borders, in order to obtain the best correlation between the experimental and numerical results. It has been shown that the use of simplified micromodels for the investigation of composite masonry-infilled RC frames requires in-depth knowledge and engineering judgement in order to be used with confidence. Modelling problems were identified and explained in detail, which in turn offer an insight to practising engineers on how to deal with them

Comparison of experimental and analytically predicted out-of-plane behavior of framed-masonry walls containing openings

During an earthquake, structures are loaded in both in-plane and out-of-plane direction. This paper investigates the behaviour of load-bearing frames with infill walls that contain openings. As when they are subjected to out-of-plane, inertial loads. In the experimental campaigns of like structures, it was found that even with openings, the beneficial arching-action was able to develop. However, its effectiveness was limited. Namely, the deformation capabilities in all cases were significantly lowered. Same can not be stated for the load-bearing capacities, as some researches found no reduction while others did. Additionally, this paper analyses the existing equations that can calculate the load-bearing capacity of such structures. Low correlations were found between the experimental and analytical capacities. Hence, further research endeavours should be addressed in order to gain a reliable analytical model

Influence of Clay Block Masonry Properties on the Out-of-Plane Behaviour of Infilled RC Frames

In order to determine the characteristics that govern the out-of-plane behaviour of masonry infills, two groups of wall specimens were built and tested in the laboratory. Specimens were assembled and tested as described in EN 1052-2 provisions and constitute of flexural strength for a plane of failure parallel and perpendicular to the bedjoints specimens. By obtaining data from experiments, numerical micromodels were developed to predict their mechanical behaviour. A calibration procedure undertaken and results obtained from the experimental campaign were found to be in agreement with those obtained from the numerical models. Additionally, former in-plane infilled frame numerical models were tested with acquired out-of-plane calibrated material model. No significant difference was found

Development and Calibration of a 3D Micromodel for Evaluation of Masonry Infilled RC Frame Structural Vulnerability to Earthquakes

Within the scope of literature, the influence of openings within the infill walls that are bounded by a reinforced concrete frame and excited by seismic drift forces in both in- and out-of-plane direction is still uncharted. Therefore, a 3D micromodel was developed and calibrated thereafter, to gain more insight in the topic. The micromodels were calibrated against their equivalent physical test specimens of in-plane, out-of-plane drift driven tests on frames with and without infill walls and openings, as well as out-of-plane bend test of masonry walls. Micromodels were rectified based on their behavior and damage states. As a result of the calibration process, it was found that micromodels were sensitive and insensitive to various parameters, regarding the model’s behavior and computational stability. It was found that, even within the same material model, some parameters had more effects when attributed to concrete rather than on masonry. Generally, the in-plane behavior of infilled frames was found to be largely governed by the interface material model. The out-of-plane masonry wall simulations were governed by the tensile strength of both the interface and masonry material model. Yet, the out-of-plane drift driven test was governed by the concrete material properties

A review of experimental and analytical studies on the out-of-plane behaviour of masonry infilled frames

This paper presents a literature review of research undertaken on the out-of-plane behaviour of masonry infilled frames. This paper also discusses the effects of bidirectional loads, openings, slenderness, boundary conditions etc. As numerous researchers have reported, these effects play a crucial role in achieving arching action cause, as they can bypass or limit its effectiveness. Namely, arching action leads to additional compressive forces which resist traversal ones. This is confirmed by inertial force methods of testing, while the same cannot be claimed for inter-storey drift or dynamical methods. It is to be acknowledged that most experimental tests were carried out using inertial force methods, mostly with the use of airbags. In contrast, only a few were undertaken with dynamical methods and just two with inter-storey drift methods. It was found that inertial force and inter-storey drift methods differ widely. In particular, inertial force methods damage the infill, leaving the frame more or less intact. Conversely, drift heavily damages the frame, while infill only slightly. Openings were investigated, albeit with contrasting results. Namely, in all cases, it was found that openings do lower the deformational but not all load-bearing capacities. Furthermore, analytical models have shown contrasting results between themselves and with experimental data. Models’ stabilities were checked with single- and multi-variable parametric analysis from which governing factors, influences of frame and other parameters were identified

Socioeconomic status and adverse birth outcomes: a population-based Canadian sample

This study assessed the strength of the association between socioeconomic status (SES) and low birth weight (LBW) and preterm birth (PTB) in Southwestern Ontario. Utilizing perinatal and neonatal databases at the London Health Science Centre, maternal postal codes were entered into a Geographic Information System to determine home neighbourhoods. Neighbourhoods were defined by dissemination areas (DAs). Median household income for each DA was extracted from the latest Canadian Census and linked to each mother. All singleton infants born between February 2009 and February 2014 were included. Of 26,654 live singleton births, 6.4% were LBW and 9.7% were PTB. Top risk factors for LBW were: maternal amphetamine use, chronic hypertension and maternal marijuana use (OR respectively: 17.51, 3.18, 2.72); previously diagnosed diabetes, maternal narcotic use and insulin-controlled gestational diabetes predicted PTB (OR respectively: 17.95, 2.69, 2.42). Overall, SES had little impact on adverse birth outcomes, although low maternal education increased the likelihood of a LBW neonate (OR: 1.01)

Factors that influence excessive gestational weight gain: Moving beyond assessment and counselling

One in four Canadian adults is obese, and more women are entering pregnancy with a higher body mass index (BMI) than in the past. Pregnant women who are overweight or obese have a higher risk of pregnancy-related complications than women of normal weight. Gestational weight gain (GWG) is also associated with childhood obesity. Although the factors influencing weight gain during pregnancy are multifaceted, little is known about the social inequality of GWG. This review will address some of the socioeconomic factors and maternal characteristics influencing weight gain and the impact that excessive GWG has on health outcomes such as post-partum weight retention. The effects of an overweight or obese pre-pregnancy BMI on GWG and neonatal outcomes will also be addressed. The timing of weight gain is also important, as recommendations now include trimester-specific guidelines. While not conclusive, preliminary evidence suggests that excessive weight gain during the first trimester is most detrimental