Early Tests of the WikiLauncher First Stage

This is a technical report for the early nine test of the first stage of a minilauncher to put up to six femto-satellites in a 250 km Low Earth Orbit. These nine tests were performed in a stone quarry in order to gain experience in real cases to see if student calculations were sized properly. The experiments and simulations were focused in three lines: Determination of the solid propellant burn rate, structural sizing and thermal load.Preprin

Harnessing the Synthetic Potential of Bis-1,1-Allyldiboron Reagents for α-Alkylations, γ- Alkylations, α-Conjugate Additions, and γ-Conjugate Additions

With increasing amounts of therapeutic and diagnostic drugs containing boron being synthesized by industry, the ability to efficiently generate them poses many obstacles, including environmental impact and monetary cost. Harnessing the power of Bis-1,1-allyldiboron reagents to perform α-alkylations, γ-alkylations, α-conjugate additions, and γ-conjugate additions with electrophilic species allows for the creation of new stereocenters and for the installation of a boronate ester which can participate in multiple types of downstream and value-added transformations, including oxidations, homologations, halogenations, aminations, and cross- couplings. Although the research is ongoing, this work begins to outline the developing theory and methodology that allows for the production of a diverse array of bioactive, boronate ester-containing molecular scaffolds that demonstrate promise for industry and organoboron literature due to their ability to operate within a simple Lewis Base, phase-transfer catalyst (PTC), crown ether system, under nonpolar solvent and low to ambient temperature conditions. Notably, the PTC system has already exhibited the ability increase site-selectivity (i.e., selection for α-product versus γ-product) for α-alkylations with secondary chlorides and α-conjugate additions as well as increasing product yield for γ-conjugate additions, demonstrating promise for directing regioselectivity and stereochemistry.Bachelor of Art

A critical knowledge pathway to low-carbon, sustainable futures: Integrated understanding of urbanization, urban areas, and carbon

Independent lines of research on urbanization, urban areas, and carbon have advanced our understanding of some of the processes through which energy and land uses affect carbon. This synthesis integrates some of these diverse viewpoints as a first step toward a coproduced, integrated framework for understanding urbanization, urban areas, and their relationships to carbon. It suggests the need for approaches that complement and combine the plethora of existing insights into interdisciplinary explorations of how different urbanization processes, and socio-ecological and technological components of urban areas, affect the spatial and temporal patterns of carbon emissions, differentially over time and within and across cities. It also calls for a more holistic approach to examining the carbon implications of urbanization and urban areas, based not only on demographics or income but also on other interconnected features of urban development pathways such as urban form, economic function, economic-growth policies, and other governance arrangements. It points to a wide array of uncertainties around the urbanization processes, their interactions with urban socio-institutional and built environment systems, and how these impact the exchange of carbon flows within and outside urban areas. We must also understand in turn how carbon feedbacks, including carbon impacts and potential impacts of climate change, can affect urbanization processes. Finally, the paper explores options, barriers, and limits to transitioning cities to low-carbon trajectories, and suggests the development of an end-to-end, coproduced and integrated scientific understanding that can more effectively inform the navigation of transitional journeys and the avoidance of obstacles along the way

Exascale Deep Learning for Climate Analytics

We extract pixel-level masks of extreme weather patterns using variants of Tiramisu and DeepLabv3+ neural networks. We describe improvements to the software frameworks, input pipeline, and the network training algorithms necessary to efficiently scale deep learning on the Piz Daint and Summit systems. The Tiramisu network scales to 5300 P100 GPUs with a sustained throughput of 21.0 PF/s and parallel efficiency of 79.0%. DeepLabv3+ scales up to 27360 V100 GPUs with a sustained throughput of 325.8 PF/s and a parallel efficiency of 90.7% in single precision. By taking advantage of the FP16 Tensor Cores, a half-precision version of the DeepLabv3+ network achieves a peak and sustained throughput of 1.13 EF/s and 999.0 PF/s respectively.Comment: 12 pages, 5 tables, 4, figures, Super Computing Conference November 11-16, 2018, Dallas, TX, US

Understanding Radiocarpal Rotation Through In Vivo Pronation and Supination of the Hand: A Single Case Study

Background: Studies have not clearly defined the motion of the distal radius in relation to the carpus in vivo. We hypothesized that 1) with the hand fixed by grasping a handle to prevent hand and wrist motion, the resulting load in torsion generated by extrinsic muscle in vivo would create motion at the radiocarpal joint; and 2) the motion measured will be between the distal radius and the proximal row of the carpus. Methods: The data was acquired from the senior author external to our institution; in the current study, we quantify the resulting radiocarpal motion. A K-wire was placed into the second metacarpal, and a second wire was placed in the distal radius. The shoulder was abducted to 90° and the hand was pronated, held stationary gripping a fixed object. The forearm was pronated and supinated to simulate radiocarpal rotation. Photographs were obtained at three points: 1) initial position showing the wire in vertical alignment; 2) same perspective in maximum internal radiocarpal rotation; and 3) same perspective in maximum external radiocarpal rotation. ImageJ (open source) was used to quantify the angle between the wires. Results: Superimposition of the three photographs in vivo allowed us to approximate two angle measurements. The measurements with maximal internal and external rotations were 16° and 24°, respectively. Conclusions: Radiocarpal rotation should be considered in addition to flexion and extension motions and radial ulnar deviations when treating degenerative changes in the wrist

Quantum pathology of static internal imperfections in flawed quantum computers

Even in the absence of external influences the operability of a quantum computer (QC) is not guaranteed because of the effects of residual one- and two-body imperfections. Here we investigate how these internal flaws affect the performance of a quantum controlled-NOT (CNOT) gate in an isolated flawed QC. First we find that the performance of the CNOT gate is considerably better when the two-body imperfections are strong. Secondly, we find that the largest source of error is due to a coherent shift rather than decoherence or dissipation. Our results suggest that the problem of internal imperfections should be given much more attention in designing scalable QC architectures

Kraus decomposition for chaotic environments including time-dependent subsystem Hamiltonians

We derive an exact and explicit Kraus decomposition for the reduced density of a quantum system simultaneously interacting with time-dependent external fields and a chaotic environment of thermodynamic dimension. We test the accuracy of the Kraus decomposition against exact numerical results for a CNOT gate performed on two qubits of an $(N+2)$-qubit statically flawed isolated quantum computer. Here the $N$ idle qubits comprise the finite environment. We obtain very good agreement even for small $N$