Representing the Process of Machine Tool Calibration in First-order Logic

Machine tool calibration requires a wide range of measurement techniques that can be carried out in many different sequences. Planning a machine tool calibration is typically performed by a subject expert with a great understanding of International standards and industrial best-practice guides. However, it is often the case that the planned sequence of measurements is not the optimal. Therefore, in an attempt to improve the process, intelligent computing methods can be designed for plan suggestion. As a starting point, this paper presents a way of converting expert knowledge into first-order logic that can be expressed in the PROLOG language. It then shows how queries can be executed against the logic to construct a knowledge-base of all the different measurements that can be performed during machine tool calibration

Simultaneous calculation of the helical pitch and the twist elastic constant in chiral liquid crystals from intermolecular torques

We present a molecular simulation method that yields simultaneously the equilibrium pitch wave number q and the twist elastic constant K2 of a chiral nematic liquid crystal by sampling the torque density. A simulation of an untwisted system in periodic boundary conditions gives the product K2q; a further simulation with a uniform twist applied provides enough information to separately determine the two factors. We test our new method for a model potential, comparing the results with K2q from a thermodynamic integration route, and with K2 from an order fluctuation analysis. We also present a thermodynamic perturbation theory analysis valid in the limit of weak chirality

Normalised Root Mean Square and Amplitude of Sidebands of Vibration Response as Tools for Gearbox Diagnosis

Quick assessment of the condition of gearboxes used in helicopters is a safety requirement. One of the most widely used helicopter on-board-mounted condition monitoring system these days is the Health and Usage Monitoring System. It has been specifically designed to monitor the condition of all safety-critical components operating in the helicopter through calculation of so-called condition indicators (CIs) - signal processing routines designed to output a single number that represents the condition of the monitored component. Among number of available parameters, there is a couple of CIs that over the years of testing have earned a reputation of being the most reliable measures of the gear tooth condition. At the same time, however, it has been observed that in some cases, those techniques do not properly indicate the deteriorating condition with the propagation of a gear tooth fault with the period of operation. Hence, three more robust methods have been suggested, which are discussed in this article

The Public Interest Inquiry for Permanent Injunctions or Exclusion Orders: Shedding the Myopic Lens

President Obama\u27s 2013 veto of a US International Trade Commission (ITC) exclusion order, issued to address Apple Inc.\u27s infringement of a patent owned by Samsung, thrust the ITC\u27s public interest inquiry into the spotlight. Historically, however, these factors rarely weighed against a remedy at the ITC. Likewise, US district courts have rarely declined to issue a permanent injunction after finding a patent valid and infringed due solely to the public interest factor--the last of the four factors that the Supreme Court put in place in eBay Inc. v. Merc Exchange, L.L.C. More recent decisions addressing the public interest in both forums, however, show a willingness by the adjudicators to weigh both traditional public interest issues, such as health and well-being, and non-traditional arguments, such as public reliance and environmental concerns, against a patent owner\u27s right to exclude. In this Article, we examine some of the successful traditional and non-traditional public interest arguments, both at the ITC and in US district courts. From this analysis, the Article outlines how parties involved in high-stakes patent litigation in either forum can craft public interest arguments to combat the threat of a permanent injunction or an ITC exclusion order

Constitutionalizing Patents: From Venice to Philadelphia

Patent law today is a complex institution in most developed economies and the appropriate structure for patent law is hotly debated around the world. Despite their differences, one crucial feature is shared by the diverse patent systems of the industrialized world even before the recent trend toward harmonization: modern patent regimes include self-imposed restrictions of executive and legislative discretion, which we refer to as constitutionalized systems. Given the lucrative nature of patent monopolies, the long history of granting patents as a form of patronage, and the aggressive pursuit of patronage in most societies, the choice to confine patents within a legal framework that minimized the potential for gain by current office holders requires explanation. Why choose to constitutionalize patents? This paper answers these questions by examining three salient constitutionalizng events through the lens of public choice theory. First, the ground breaking Venetian statute of 1474, the first modern patent system; second, the British experience with patents that led to the 1624 Statute of Monopolies, one of the key foundations of the U.S. patent system; and lastly, the American Founders\u27 adoption of Article I, Section 8, Clause 8 of the Constitution, which grants the power to, and sets forth the manner in which, the national government can issue patents. We argue that creating constitutional patent law institutions offered the opportunity to both increase the durability of the bargain between the state and the inventor and, in some cases, to limit the grant of patents to those most likely to increase the general welfare. Based on the historical analysis, we derive three desirable features for patent law institutions: (1) strong constraints on the type of patents that can be issued, limiting them to areas in which there is evidence that the costs of the limits to competition imposed are justified by the benefits produced by the incentives created; (2) an independent institution capable of reviewing the grant of a patent in a timely and final manner, to ensure the constitutional bargain is kept; and (3) patents that provide their owners with a sense of security in the validity and scope of their property right, to maximize the value of the bargaining chip offered to inventors. Our analysis thus offers lessons for countries considering new patent law institutions or modifying existing ones

Screening properties of Gaussian electrolyte models, with application to dissipative particle dynamics

We investigate the screening properties of Gaussian charge models of electrolyte solutions by analysing the asymptotic behaviour of the pair distribution functions. We use a combination of Monte-Carlo simulations with the hyper-netted chain integral equation closure, and the random phase approximation, to establish the conditions under which a screening length is well defined and the extent to which it matches the expected Debye length. For practical applications, for example in dissipative particle dynamics, we are able to summarise our results in succinct rules-of-thumb which can be used for mesoscale modeling of electrolyte solutions. We thereby establish a solid foundation for future work, such as the systematic incorporation of specific ion effects.Comment: 9 pages, 9 figures, 1 table, RevTeX4-

Development of a low-maintenance measurement approach to continuously estimate methane emissions: a case study

The chemical breakdown of organic matter in landfills represents a significant source of methane gas (CH4). Current estimates suggest that landfills are responsible for between 3% and 19% of global anthropogenic emissions. The net CH4 emissions resulting from biogeochemical processes and their modulation by microbes in landfills are poorly constrained by imprecise knowledge of environmental constraints. The uncertainty in absolute CH4 emissions from landfills is therefore considerable. This study investigates a new method to estimate the temporal variability of CH4 emissions using meteorological and CH4 concentration measurements downwind of a landfill site in Suffolk, UK from July to September 2014, taking advantage of the statistics that such a measurement approach offers versus shorter-term, but more complex and instantaneously accurate, flux snapshots. Methane emissions were calculated from CH4 concentrations measured 700 m from the perimeter of the landfill with observed concentrations ranging from background to 46.4 ppm. Using an atmospheric dispersion model, we estimate a mean emission flux of 709 μg m−2 s−1 over this period, with a maximum value of 6.21 mg m−2 s−1, reflecting the wide natural variability in biogeochemical and other environmental controls on net site emission. The emissions calculated suggest that meteorological conditions have an influence on the magnitude of CH4 emissions. We also investigate the factors responsible for the large variability observed in the estimated CH4 emissions, and suggest that the largest component arises from uncertainty in the spatial distribution of CH4 emissions within the landfill area. The results determined using the low-maintenance approach discussed in this paper suggest that a network of cheaper, less precise CH4 sensors could be used to measure a continuous CH4 emission time series from a landfill site, something that is not practical using far-field approaches such as tracer release methods. Even though there are limitations to the approach described here, this easy, low-maintenance, low-cost method could be used by landfill operators to estimate time-averaged CH4 emissions and their impact downwind by simultaneously monitoring plume advection and CH4 concentrations