4,348 research outputs found
A New Technique for System-to-system Transfer of Surface Data
The purpose is to describe a recently developed technique aimed at providing a universal interface between surface types. In brief, a software package was developed which functions a common denominator of CAD/CAM surface types. This software enable one to convert from any given surface representation to any other target representation. The tiles maintain the same slope continuity as the target surface gram, bicubic patches are used since they allow one to match point, slope, and twist vectors to the target surface. Thus, slopes can be continuous or discontinuous as they are on the target surface. The patches can be of lower order if desired. For example, if only point information is available, the patches produced will be bilinear; however, the number of patches required is likely to increase correspondingly. The patches can be of higher order although many systems will not accept patches of more than order four. The final result of the program is a rectangular grid of bicubic patches. The patches fit the target surface exactly at their corners. Also, the patch corners have the same tangent and twist vectors. Adjacent patches will have slope continuity, unless a discontinuity was indicated by the target surface
Increased surface flashover voltage in microfabricated devices
With the demand for improved performance in microfabricated devices, the
necessity to apply greater electric fields and voltages becomes evident. When
operating in vacuum, the voltage is typically limited by surface flashover
forming along the surface of a dielectric. By modifying the fabrication process
we have discovered it is possible to more than double the flashover voltage.
Our finding has significant impact on the realization of next-generation micro-
and nano-fabricated devices and for the fabrication of on-chip ion trap arrays
for the realization of scalable ion quantum technology
PUBLIC ATTITUDES IN THE NORTHEAST REGION TOWARD RECOMBINANT PORCINE SOMATOTROPIN
This study explored the attitudes of consumers regarding the use of recombinant porcine somatotropin (PST) in the production of pork, and the association between the attitudes and individual socioeconomic characteristics. The data were collected from surveys of households located in the New York and Philadelphia metropolitan area. The results show that both gender and education may play a role in the level of concern regarding the use of PST. Education programs which address the safety of pork produced with PST need to target the lower-educated and female consumers. More-over, the education program should be developed by organizations which are trusted by the public, such as universities and public agencies.Food Consumption/Nutrition/Food Safety,
Data related to cyclic deformation and fatigue behavior of direct laser deposited Tiā6Alā4V with and without heat treatment
AbstractData is presented describing the strain-controlled, fully-reversed uniaxial cyclic deformation and fatigue behavior of Tiā6Alā4V specimens additively manufactured via Laser Engineered Net Shaping (LENS) ā a Direct Laser Deposition (DLD) process. The data was collected by performing multiple fatigue tests on specimens with various microstructural states/conditions, i.e. in their āas-builtā, annealed (below the beta transus temperature), or heat treated (above the beta transus temperature) condition. Such data aids in characterizing the mechanical integrity and fatigue resistance of DLD parts. Data presented herein also allows for elucidating the strong microstructure coupling of the fatigue behavior of DLD Tiā6Alā4V, as the data trends were found to vary with material condition (i.e. as-built, annealed or heat treated) [1]. This data is of interest to the additive manufacturing and fatigue scientific communities, as well as the aerospace and biomedical industries, since additively-manufactured parts cannot be reliably deployed for public use, until their mechanical properties are understood with high certainty
Specializing Interpreters using Offline Partial Deduction
We present the latest version of the Logen partial evaluation system for logic programs. In particular we present new binding-types, and show how they can be used to effectively specialise a wide variety of interpreters.We show how to achieve Jones-optimality in a systematic way for several interpreters. Finally, we present and specialise a non-trivial interpreter for a small functional programming language. Experimental results are also presented, highlighting that the Logen system can be a good basis for generating compilers for high-level languages
Kinematics and helicity evolution of a loop-like eruptive prominence
We aim at investigating the morphology, kinematic and helicity evolution of a
loop-like prominence during its eruption. We use multi-instrument observations
from AIA/SDO, EUVI/STEREO and LASCO/SoHO. The kinematic, morphological,
geometrical, and helicity evolution of a loop-like eruptive prominence are
studied in the context of the magnetic flux rope model of solar prominences.
The prominence eruption evolved as a height expanding twisted loop with both
legs anchored in the chromosphere of a plage area. The eruption process
consists of a prominence activation, acceleration, and a phase of constant
velocity. The prominence body was composed of left-hand (counter-clockwise)
twisted threads around the main prominence axis. The twist during the eruption
was estimated at 6pi (3 turns). The prominence reached a maximum height of 526
Mm before contracting to its primary location and partially reformed in the
same place two days after the eruption. This ejection, however, triggered a CME
seen in LASCO C2. The prominence was located in the northern periphery of the
CME magnetic field configuration and, therefore, the background magnetic field
was asymmetric with respect to the filament position. The physical conditions
of the falling plasma blobs were analysed with respect to the prominence
kinematics. The same sign of the prominence body twist and writhe, as well as
the amount of twisting above the critical value of 2pi after the activation
phase indicate that possibly conditions for kink instability were present. No
signature of magnetic reconnection was observed anywhere in the prominence body
and its surroundings. The filament/prominence descent following the eruption
and its partial reformation at the same place two days later suggest a confined
type of eruption. The asymmetric background magnetic field possibly played an
important role in the failed eruption.Comment: 9 pages, 8 figures, in press in A&
Deductive synthesis of recursive plans in linear logic
Linear logic has previously been shown to be suitable for describing and deductively solving planning problems involving conjunction and disjunction. We introduce a recursively defined datatype and a corresponding induction rule, thereby allowing recursive plans to be synthesised. In order to make explicit the relationship between proofs and plans, we enhance the linear logic deduction rules to handle plans as a form of proof term
Atropisomerism in Diarylamines:Structural Requirements and Mechanisms of Conformational Interconversion
In common with other hindered structures containing two aromatic rings linked by a short tether, diarylamines may exhibit atropisomerism (chirality due to restricted rotation). Previous examples have principally been tertiary amines, especially those with cyclic scaffolds. Little is known of the structural requirement for atropisomerism in structurally simpler secondary and acyclic diarylamines. In this paper we describe a systematic study of a series of acyclic secondary diarylamines, and we quantify the degree of steric hindrance in the ortho positions that is required for atropisomerism to result. Through a detailed experimental and computational analysis, the role of each orthoāsubstituent on the mechanism and rate of conformational interconversion is rationalised. We also present a simple predictive model for the design of configurationally stable secondary diarylamines
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