A Fast and Accurate Algorithm for Spherical Harmonic Analysis on HEALPix Grids with Applications to the Cosmic Microwave Background Radiation

The Hierarchical Equal Area isoLatitude Pixelation (HEALPix) scheme is used extensively in astrophysics for data collection and analysis on the sphere. The scheme was originally designed for studying the Cosmic Microwave Background (CMB) radiation, which represents the first light to travel during the early stages of the universe's development and gives the strongest evidence for the Big Bang theory to date. Refined analysis of the CMB angular power spectrum can lead to revolutionary developments in understanding the nature of dark matter and dark energy. In this paper, we present a new method for performing spherical harmonic analysis for HEALPix data, which is a central component to computing and analyzing the angular power spectrum of the massive CMB data sets. The method uses a novel combination of a non-uniform fast Fourier transform, the double Fourier sphere method, and Slevinsky's fast spherical harmonic transform (Slevinsky, 2019). For a HEALPix grid with $N$ pixels (points), the computational complexity of the method is $\mathcal{O}(N\log^2 N)$, with an initial set-up cost of $\mathcal{O}(N^{3/2}\log N)$. This compares favorably with $\mathcal{O}(N^{3/2})$ runtime complexity of the current methods available in the HEALPix software when multiple maps need to be analyzed at the same time. Using numerical experiments, we demonstrate that the new method also appears to provide better accuracy over the entire angular power spectrum of synthetic data when compared to the current methods, with a convergence rate at least two times higher

Adjusting to Globalization: Challenges for the Canadian Banking System

The mid-1960s were the good old days for Canadian bankers before the Canadian banking system was opened up to foreign competition. Now it is a whole new competitive ball game as Edward P. Neufeld points out in his paper on the challenges that globalization poses for the Canadian banking system. He argues that the ability of Canadian institutions to withstand increasing foreign competition will depend on their economic efficiency relative to that of the encroaching competitors. In his view, the forces that have facilitated globalization of financial services have also made obsolete past measures of economies of scale and of the “optimum” size of financial institutions, and past guidelines concerning excessive domestic market concentration are no longer reliable. For Canadian financial institutions to experience solid growth in the future will require them to be internationally competitive at home and abroad. But unfortunately they have been slipping down the list of important international financial institutions as measured by the size of their assets and of their capital bases, and as a result their non-interest costs are 10 to 20 per cent higher than they would be if mergers were permitted. Otherwise, the forces of globalization will generate a persistent tendency towards increased foreign ownership of Canadian financial institutions, as has already begun to happen, and towards an increase in non-Canadian executives running them. Neufeld is very concerned that Bill C-8, which is the new legislation reforming the financial service sector passed this year, contains discrimina- tory measures that will undermine the international competitiveness of the Canadian banking system. These include: a restrictive and politicized bank merger policy, which risks preventing Canadian banks from achieving the economies of scale that their much larger international competitors are achieving; the continued prohibition against the distribution of life insurance through bank branches, which directly restricts competition in the Canadian market; the continued exclusion of the banks from the car leasing business, a business almost completely dominated by foreign institutions; and the threat in the bill directed at the large Canadian banks, and not at smaller competing institutions or foreign institutions located in Canada or entering the Canadian market through the Internet, that if they do not provide certain low-cost services they will be forced to do so. In Neufeld’s view, the most glaring weakness of the new policy as concerns competition is its failure to recognize clearly that by far the most important source of future competition will be large international institutions operating directly in Canada and through the Internet from outside Canada. He regards the merger process as flawed in that it is tortuous, and therefore inevitably subject to long delays, and risks being hostage to short-term political considerations. Neufeld believes that the key question that needs to be addressed is not whether Canadians will get the world-class financial services they require, because international competition will ensure that, but whether the services will be provided by Canadian banks or foreign financial institutions.Canada, Banking, Banks, Financial Services, Mergers, Market Concentration, Bill C-8

Six Pillars of Social Policy: The State of Pensions and Health Care in Canada

William B.P. Robson, a co-author with David Slater of a series of papers on pension issues, has written an ambitious survey of the state of Canadian economic policy in the areas of pensions and health care. He argues that it is appropriate to tackle both issues in the same paper because they are both major spending programs strongly related to the life cycle of Canadians, and face challenges arising from the aging of the population. Robson notes that the pension debate uses the metaphor of three pillars to describe a comprehensive pension system: a safety net to guard against destitution in old age; a mandatory employment-related system to provide basic replacement income; and a voluntary system supported by provisions that reduce the double-taxation of saving. The main elements of public policy related to pensions in Canada cover these pillars. He recognizes that all three of the pillars cannot be directly applied to health care, but he argues that the three-pillar metaphor is still a fruitful perspective because it facilitates constructive responses to the pressures confronting Canada’s health system and illuminates interactions between the pension and health systems. Hence his title “six pillars of social policy”. Based on his examination of Canada’s pension and health-care systems, Robson makes a number of recommendations. First, he advocates more prefunding in both the pension and health areas to cover the future cost of the aging baby-boom cohort. Second, he recommends a gradual increase in the normal age of eligibility for pension benefits. Third, he recommends the creation of a second pillar, a mandatory contribution scheme in the health area as a way to avoid the development of a means-tested system that would exacerbate the disincentives to work and save. Fourth, he puts forward the idea of a new type of saving vehicle that provides tax-relief on distributions rather than on contributions so that Canadians can avoid the high marginal effective tax rates associated with means-tested programs.Health, Health Care, Health-care, Healthcare, Canada, Pensions, CPP, Retirement, Mandatory Contribution, Aging, Ageing

Identifying experts and authoritative documents in social bookmarking systems

Social bookmarking systems allow people to create pointers to Web resources in a shared, Web-based environment. These services allow users to add free-text labels, or “tags”, to their bookmarks as a way to organize resources for later recall. Ease-of-use, low cognitive barriers, and a lack of controlled vocabulary have allowed social bookmaking systems to grow exponentially over time. However, these same characteristics also raise concerns. Tags lack the formality of traditional classificatory metadata and suffer from the same vocabulary problems as full-text search engines. It is unclear how many valuable resources are untagged or tagged with noisy, irrelevant tags. With few restrictions to entry, annotation spamming adds noise to public social bookmarking systems. Furthermore, many algorithms for discovering semantic relations among tags do not scale to the Web. Recognizing these problems, we develop a novel graph-based Expert and Authoritative Resource Location (EARL) algorithm to find the most authoritative documents and expert users on a given topic in a social bookmarking system. In EARL’s first phase, we reduce noise in a Delicious dataset by isolating a smaller sub-network of “candidate experts”, users whose tagging behavior shows potential domain and classification expertise. In the second phase, a HITS-based graph analysis is performed on the candidate experts’ data to rank the top experts and authoritative documents by topic. To identify topics of interest in Delicious, we develop a distributed method to find subsets of frequently co-occurring tags shared by many candidate experts. We evaluated EARL’s ability to locate authoritative resources and domain experts in Delicious by conducting two independent experiments. The first experiment relies on human judges’ n-point scale ratings of resources suggested by three graph-based algorithms and Google. The second experiment evaluated the proposed approach’s ability to identify classification expertise through human judges’ n-point scale ratings of classification terms versus expert-generated data

Scale Model Investigations of the Effects of Flow Conditioning Devices

A scale model was constructed of a portion of a supersonic wind tunnel to perform experiments on various flow conditioning devices. The various devices researched were: swirl vanes, screens, honeycombs, and various combinations thereof. Each flow conditioning device was analyzed to show its effect on total pressure profiles, static pressure profiles, test section flow angularity, test section turbulence, and acoustic noise. Of most concern are the effects flow conditioning devices have on temporal fluctuation of previously mentioned parameters. The data from these experiments were used as the basis for selecting a screen-honeycomb combination to be installed in the full-scale tunnel. The selected configuration consisted of two diffuser exit screens in combination with a long cell honeycomb in the stilling chamber. The selected configuration also included the existing screen across corner 4 and swirl vanes. It was concluded that these devices provide a net benefit and should not be removed. This configuration reduced test section flow angularity fluctuations to a very low level in the test section of the model; however, it did not eliminate transitory stall in the crossleg diffuser. Intermediate screens installed in the diffuser and, most likely, screens of some other treatment at the inlet of the diffuser would be required to completely eliminate unsteadiness in the diffuser. These treatments would involve both installation cost and an increase in operation cost because of the associated increase in power requirements due to their location in high-speed flow. The experimental data, however, do show that intermediate screens in the diffuser are very effective at reducing flow unsteadiness downstream of the screen location. This thesis presents a discussion on the methodology to conduct the experimental program and the results each combination of flow conditioning devices had on the various research parameters

Master to Pawn: Cicero\u27s Involvement in the Collapse of Republican Rome

This essay looks at the life of Cicero, focusing on his actions towards the end of the Roman Republic and his relationship with Octavian. The paper follows his rise to fame and power, then his actions during the chaotic civil wars of 1st century BC and the dictatorship of Julius Caesar, then finally the post-Caesar era and Cicero\u27s eventual death. It focuses especially on his interactions with Octavian, and the unfortunate ending of their friendship

Unveiling Su Aurigae in the near Infrared: New high spatial resolution results using Adaptive Optics

We present here new results on circumstellar nebulosity around SU Aurigae, a T-Tauri star of about 2 solar mass and 5 Myrs old at 152 pc in the J, H and K bands using high resolution adaptive optics imaging (0\farcs30) with the Penn state IR Imaging Spectrograph (PIRIS) at the 100 inch Mt. Wilson telescope. A comparison with HST STIS optical (0.2 to 1.1 micron) images shows that the orientation of the circumstellar nebulosity in the near-IR extends from PAs 210 to 270 degrees in H and K bands and up to 300 degrees in the J band. We call the circumstellar nebulosity seen between 210 to 270 degrees as 'IR nebulosity'. We find that the IR nebulosity (which extends up to 3.5 arcsecs in J band and 2.5 arcsecs in the K band) is due to scattered light from the central star. The IR nebulosity is either a cavity formed by the stellar outflows or part of the circumstellar disk. We present a schematic 3-dimensional geometrical model of the disk and jet of SU Aur based on STIS and our near-IR observations. According to this model the IR nebulosity is a part of the circumstellar disk seen at high inclination angles. The extension of the IR nebulosity is consistent with estimates of the disk diameter of 50 to 400 AU in radius, from earlier mm, K band interferometric observations and SED fittings.Comment: Accepted for publications in the Astronomical Journal, to appear in the May issue of the Journa

Removable Window System for Space Vehicles

A window system for a platform comprising a window pane, a retention frame, and a biasing system. The window pane may be configured to contact a sealing system. The retention frame may be configured to contact the sealing system and hold the window pane against the support frame. The biasing system may be configured to bias the retention frame toward the support frame while the support frame and the retention frame are in a configuration that holds the window pane. Removal of the biasing system may cause the retention frame and the window pane to be removable