The test function conjecture for local models of Weil-restricted groups

We prove the test function conjecture of Kottwitz and the first named author for local models of Shimura varieties with parahoric level structure attached to Weil-restricted groups, as defined by B. Levin. Our result covers the (modified) local models attached to all connected reductive groups over $p$-adic local fields with $p\geqslant 5$. In addition, we give a self-contained study of relative affine Grassmannians and loop groups formed using general relative effective Cartier divisors in a relative curve over an arbitrary Noetherian affine scheme.

Triviality Properties of Principal Bundles on Singular Curves. II

For $G$ a split semi-simple group scheme and $P$ a principal $G$-bundle on a relative curve $X\rightarrow S$, we study a natural obstruction for the triviality of $P$ on the complement of a relatively ample Cartier divisor $D\subset X$. We show, by constructing explicit examples, that the obstruction is nontrivial if $G$ is not simply connected, but it can be made to vanish by a faithfully flat base change, if $S$ is the spectrum of a dvr (and some other hypotheses). The vanishing of this obstruction is shown to be a sufficient condition for étale local triviality if $S$ is a smooth curve, and the singular locus of $X-D$ is finite over $S$.

Effect of corrugated skins on the aerodynamic performance of the cambered airfoils

Purpose This paper aims to study the effect of corrugated skins on the aerodynamic performance of the cambered NACA 0012 airfoils at different corrugations parameters, maximum cambers, Reynolds numbers and maximum camber locations. Design/methodology/approach In this work, numerical approach is concerned, and results are obtained based on the finite volume approach. To characterize the effect of corrugated skins, the NACA 0012-corrugated airfoil section is chosen as the base airfoil, and different cambered corrugated airfoil sections are obtained by inclusion the camber to the base airfoil. In this research, the corrugation shape is a sinusoidal wave and corrugated skins are in the aft 30 per cent of airfoil chord. To investigate the effect of corrugations on the cambered sections, the drag coefficient and averaged lift curve slope for the corrugated airfoils are compared to those of the corresponding smooth sections. Findings Results indicate that the effect of increase in the maximum camber and also Reynolds number on the relative zero-incidence drag coefficient is of little importance at low corrugation amplitudes, whereas at high corrugation, amplitude results in different behaviors. It is found that as the maximum camber increases, the deterioration in the relative curve slope introduced by corrugated skins is reduced, and reduction in this deterioration is significant for high corrugation amplitudes airfoils. It is shown that an increase in the maximum camber location has nearly no effect on the relative zero-incidence drag coefficient and also relative lift curve slope. Originality/value The outcome of the present research provides the clues for better understanding of the effect of different corrugations parameters on the aerodynamic performance of the unmanned air vehicles to have as high aerodynamic performance as possible in different mission profiles of such vehicles.

The main theorem

This chapter introduces the main theorem, which states: Let V be a quasi-projective variety over a valued field F and let X be a definable subset of V x Γ‎superscript Script Small l subscript infinity over some base set V ⊂ VF ∪ Γ‎, with F = VF(A). Then there exists an A-definable deformation retraction h : I × unit vector X → unit vector X with image an iso-definable subset definably homeomorphic to a definable subset of Γ‎superscript w subscript Infinity, for some finite A-definable set w. The chapter presents several preliminary reductions to essentially reduce to a curve fibration. It then constructs a relative curve homotopy and a liftable base homotopy, along with a purely combinatorial homotopy in the Γ‎-world. It also constructs the homotopy retraction by concatenating the previous three homotopies together with an inflation homotopy. Finally, it describes a uniform version of the main theorem with respect to parameters.

Study of Main Propulsion Plant’s Mission Reliability in View of Performance Degradation

The reliability of watercraft depends to a large extent on the reliability of main propulsion plant. It should be distinguished on the base of mission variation charged by watercraft during study of main propulsion plant’s reliability. The mission reliability under rated and economical speed is studied via one main propulsion plant as subject in this paper, while the influence performance degradation of main propulsion plant on its mission reliability mostly studied. Relative curve between mission reliability and working time has been found. The results show that, reliability model in view of performance degradation has good expansibility, approach more to actual malfunction of main propulsion plant, as well as evaluates performance of main propulsion plant well and truly. The results could be guidance for user to establish maintenance schedule in order to improve the mission reliability of main propulsion plant.

Simulation and Analysis of Butterfly-Inspired Eclosion Deployable Structure

Deployable structures, as an important kind of structure, have been widely used in a variety of satellite antennas and space reflectors. The research of deployable structures usually faces a series of theoretical and technical challenges because the size and mass are not only the limitations of deployable structure but also the key issues in the design process. Nevertheless, the appearance of bionic provides a new concept to develop the deployable structures. Inspired by the eclosion and development of butterfly wings, a bionic inflatable deployment structure has been presented in this paper. The whole system of emulate model is established and has a simulation analyzed with the help of dynamic analysis software. This simulation is aimed at emulating the deploying process, and calculating the stress distribution of the structure. Then some relative curve fitting is conducted on the deploying trajectory. A prototype has been fabricated and tested to be able to deploy smoothly and steadily.

Study of CODOG Propulsion System Mission Reliability

The component and mission of CODOG propulsion system were analyzed in this paper. According to the mission variation, different operation conditions were introduced and mission reliability models of each condition were established by the use of reliability theory. After reliability data of main component of CODOG propulsion system been obtained, mission reliability of each condition was calculated and its phased mission was simulated through MATLAB software. Relative curve between system reliability and working time was found. The results show that, mission reliability of cruise condition is the biggest while phased mission reliability is the smallest. System availability is bigger than reliability after taking maintainability into account. System reliability can increase to a great extent and its useful life is longer by improving maintainability of its component.

Formule du conducteur pour un caractère l-adique

LetKbe a local field of equal characteristicp>2, letXK/Kbe a smooth proper relative curve, and letbe a rank 1 smoothl-adic sheaf (l≠p) on a dense open subsetUKXK. In this paper, under some assumptions on the wild ramification of, we prove a conductor formula that computes the Swan conductor of the etale cohomology of the vanishing cycles of. Our conductor formula is a generalization of the conductor formula of Bloch, but for non-constant coefficients.