Precise, scalable, and low-cost manufacturing of microperforated cylindrical tube as a broadband acoustic ventilation barrier

Broadband acoustic ventilation barrier, which can simultaneously block acoustic transmission and maintain ventilation of air flow, promotes potential air-permeable yet sound-proofing applications in green buildings. Emerging microperforated cylindrical tube has demonstrated broadband acoustic attenuation, especially in the low frequency range, as well as sufficient ventilation, which is enabled by micron-scale perforations over the entire surface of cylindrical shell. Therefore, precise manufacturing technology is desirably demanded to fabricate microperforated cylindrical tubes at large scale and economically. In this project, we develop a synchronization assistant control (SAC) system that is integrated with a computer numerical control (CNC) drilling system for continuous fabrication of microperforated cylindrical tubes. The SAC system consists of an Arduino microprocesses and a stepper motor to synchronize rotation of the tube corresponding to progress of CNC drilling along the axial direction of tube. Two manual transitional stages are applied to accurately align the center position of drill bit if any drill bit is replaced. Taking advantages of CNC precision drilling, SAC synchronized rotation control as well as accurate alignment of drill bits, the microperforated cylindrical tube can be fabricated in a continuous, automatic, and reliable manner

A Case for Personal Meetings with the Federal Ethics Commissioner

Every province and territory in Canada has an independent ethics commissioner, along with ethics rules, and so too does the House of Commons, the Senate, and cabinet. The ethics regime for the House of Commons and the cabinet, however, appears to be the least successful of these ethics regimes in preventing breach of the rules. This article identifies the major weaknesses of the federal ethics regime. While in most other jurisdictions the ethics commissioner meets annually with all legislators to explain the rules, the extensive mandate of the federal ethics commissioner makes fulfilling the primary function – prevention through education – challenging. Face-to-face meetings between the ethics commissioner and members of the House of Commons and cabinet rarely occur. The author reviews inquiries made by the two House of Commons commissioners since 2004, and argues that many of the inquiries would have been unnecessary if face-to-face meetings had been held

Education and Anti-Semitism

Many people believe that intolerance, in general, and anti-Semitism, in particular, are a function of ignorance, and the solution is education. We see evidence of this whenever concerns about intolerance or anti-Semitism become more salient. Proposed solutions frequently feature improved Holocaust education or expanded diversity, equity, and inclusion training. As two religious leaders recently urged, “The only thing that will truly halt the rise of anti-Semitism in America is education” (Stanton & Marcus, 2019). Profiles of anti-Semites tend to feature rural whites or urban minorities, but they are almost always from low-educational backgrounds. Well-educated people tend to feel secure in their higher social class circles and imagine that the dangers of inter-group hatred are concentrated elsewhere

Mirror Maps in Chern-Simons Gauge Theory

We describe mirror symmetry in N=2 superconformal field theories in terms of a dynamical topology changing process of the principal fiber bundle associated with a topological membrane. We show that the topological symmetries of Calabi-Yau sigma-models can be obtained from discrete geometric transformations of compact Chern-Simons gauge theory coupled to charged matter fields. We demonstrate that the appearence of magnetic monopole-instantons, which interpolate between topologically inequivalent vacua of the gauge theory, implies that the discrete symmetry group of the worldsheet theory is realized kinematically in three dimensions as the magnetic flux symmetry group. From this we construct the mirror map and show that it corresponds to the interchange of topologically non-trivial matter field and gauge degrees of freedom. We also apply the mirror transformation to the mean field theory of the quantum Hall effect. We show that it maps the Jain hierarchy into a new hierarchy of states in which the lowest composite fermions have the same filling fractions.Comment: 40 pages LaTeX, 4 postscript files, uses psfig.sty; minor textual changes, typos corrected, references adde

The Ontario Court of Appeal and Speedy Justice

The authors use a data sample collected from the Ontario Court of Appeal minute books between 1983 and 1987 to analyze how appeals move through the province\u27s highest court. Criminal and, chiefly, sentence appeals dominate the Court\u27s agenda. Hearing times-the duration of argument and rendering of judgment-are shorter than commonly believed, most often lasting less than twenty minutes. Elapsed times-the period between end of trial and beginning of hearing-are, on average, 77 per cent longer for civil than criminal appeals, 52 per cent longer for defendant than crown appeals, and 23 per cent longer for fall than spring appeals. Elapsed times are also compared with data on United States appeal courts, and the use of appellate case-flow management is considered

The Ontario Court of Appeal and Speedy Justice

The authors use a data sample collected from the Ontario Court of Appeal minute books between 1983 and 1987 to analyze how appeals move through the province\u27s highest court. Criminal and, chiefly, sentence appeals dominate the Court\u27s agenda. Hearing times-the duration of argument and rendering of judgment-are shorter than commonly believed, most often lasting less than twenty minutes. Elapsed times-the period between end of trial and beginning of hearing-are, on average, 77 per cent longer for civil than criminal appeals, 52 per cent longer for defendant than crown appeals, and 23 per cent longer for fall than spring appeals. Elapsed times are also compared with data on United States appeal courts, and the use of appellate case-flow management is considered