13,389 research outputs found
Basic avionics module design for general aviation aircraft
The design of an advanced digital avionics system (basic avionics module) for general aviation aircraft operated with a single pilot under IFR conditions is described. The microprocessor based system provided all avionic functions, including flight management, navigation, and lateral flight control. The mode selection was interactive with the pilot. The system used a navigation map data base to provide operation in the current and planned air traffic control environment. The system design included software design listings for some of the required modules. The distributed microcomputer uses the IEEE 488 bus for interconnecting the microcomputer and sensors
The effects of inflation on growth and fluctuations in dynamic macroeconomic models
Economic Growth;Macroeconomic Models;Inflation;Monetary Models
Revolutionaries and spies on trees and unicyclic graphs
A team of {\it revolutionaries} and a team of {\it spies} play a game
on a graph . Initially, revolutionaries and then spies take positions at
vertices. In each subsequent round, each revolutionary may move to an adjacent
vertex or not move, and then each spy has the same option. The revolutionaries
want to hold an {\it unguarded meeting}, meaning revolutionaries at some
vertex having no spy at the end of a round. To prevent this forever, trivially
at least \min\{|V(G)|,\FL{r/m}\} spies are needed. When is a tree, this
many spies suffices. When is a unicyclic graph, \min\{|V(G)|,\CL{r/m}\}
spies suffice, and we characterize those unicyclic graphs where \FL{r/m}+1
spies are needed. \def\FL#1{\lfloor #1 \rfloor} \def\CL#1{\lceil #1 \rceil}Comment: 9 page
A Method of Developing Analytical Multipartite Delocalization Measures for Mixed W-like States
We present a method of developing analytical measures of -partite
delocalization in arbitrary -body W-like states, otherwise known as mixed
states in the single excitation subspace. These measures calculate the distance
of a state to its closest reference state with entanglement. We find that
the reference state is determined by the purity of the state undergoing
measurement. Measures with up to 6-body delocalization for a 6-body system are
derived in full, while an algorithm for general -partite measures is given.Comment: 8 pages, 3 figure
STOL aircraft transient ground effects. Part 1: Fundamental analytical study
The first phases of a fundamental analytical study of STOL ground effects were presented. Ground effects were studied in two dimensions to establish the importance of nonlinear effects, to examine transient aspects of ascent and descent near the ground, and to study the modelling of the jet impingement on the ground. Powered lift system effects were treated using the jet-flap analogy. The status of a three-dimensional jet-wing ground effect method was presented. It was shown, for two-dimensional unblown airfoils, that the transient effects are small and are primarily due to airfoil/freestream/ground orientation rather than to unsteady effects. The three-dimensional study showed phenomena similar to the two-dimensional results. For unblown wings, the wing/freestream/ground orientation effects were shown to be of the same order of magnitude as for unblown airfoils. This may be used to study the nonplanar, nonlinear, jet-wing ground effect
Procurement push and marketing pull in supply chain management: the conceptual contribution of relationship marketing as a driver in project financial performance
? The agenda for supply management practices on construction projects originated from clients. It is largely procurement driven, the dominant strategy of contractors being to emulate the client approach, and hence push the procurement model along the chain.? This procurement push along the supply chain translates the intrinsic client interest in value into a contractor interest in repeat business from the same client or through referral markets, the consequence being: (i) loss of interest in adding further value along the chain, (ii) continuous improvement prematurely reaches the law of diminishing returns through a primary cost reduction focus, (iii) supply chains may be rationalised in terms of the number of suppliers for each link in the chain, yet the procurement push increases chain length in order to squeeze the lowest costs possible, hence those doing the work at the bottom of the chain will not have the resources to add value nor necessarily be aware of the strategic principles at the top of the chain. ? Marketing is the other side of the same ?procurement coin?; relationship marketing (RM) soliciting a pull in the supply chain, potentially adding value for continuous improvement. ? Finally, the RM approach will be related to the theoretical and actual decoupling point for construction, with the potential to move the point towards the start of the chain, hence increasing the potential for agile manufacturing
Design and in Vitro Evaluation of a New Nano-Microparticulate System for Enhanced Aqueous-Phase Solubility of Curcumin
Curcumin, a yellow polyphenol derived from the turmeric Curcuma longa, has been associated with a diverse therapeutic potential including anti-inflammatory, antioxidant, antiviral, and anticancer properties. However, the poor aqueous solubility and low bioavailability of curcumin have limited its potential when administrated orally. In this study, curcumin was encapsulated in a series of novel nano-microparticulate systems developed to improve its aqueous solubility and stability. The nano-microparticulate systems are based entirely on biocompatible, biodegradable, and edible polymers including chitosan, alginate, and carrageenan. The particles were synthesized via ionotropic gelation. Encapsulating the curcumin into the hydrogel nanoparticles yielded a homogenous curcumin dispersion in aqueous solution compared to the free form of curcumin. Also, the in vitro release profile showed up to 95% release of curcumin from the developed nano-microparticulate systems after 9 hours in PBS at pH 7.4 when freeze-dried particles were used.CONACYTCUPIAPharmac
Electrical Characterization of PbZr0.4Ti0.6O3 Capacitors
We have conducted a careful study of current-voltage (I-V) characteristics in
fully integrated commercial PbZr0.4Ti0.6O3 thin film capacitors with Pt bottom
and Ir/IrO2 top electrodes. Highly reproducible steady state I-V were obtained
at various temperatures over two decades in voltage from current-time data and
analyzed in terms of several common transport models including space charge
limited conduction, Schottky thermionic emission under full and partial
depletion and Poole-Frenkel conduction, showing that the later is the most
plausible leakage mechanism in these high quality films. In addition,
ferroelectric hysteresis loops and capacitance-voltage data were obtained over
a large range of temperatures and discussed in terms of a modified
Landau-Ginzburg-Devonshire theory accounting for space charge effects.Comment: 17 pages, 7 figure
Helminths in the hygiene hypothesis:Sooner or later?
There is increasing recognition that exposures to infectious agents evoke fundamental effects on the development and behaviour of the immune system. Moreover, where infections (especially parasitic infections) have declined, immune responses appear to be increasingly prone to hyperactivity. For example, epidemiological studies of parasite-endemic areas indicate that prenatal or early-life experience of infections can imprint an individual's immunological reactivity. However, the ability of helminths to dampen pathology in established inflammatory diseases implies that they can have therapeutic effects even if the immune system has developed in a low-infection setting. With recent investigations of how parasites are able to modulate host immune pathology at the level of individual parasite molecules and host cell populations, we are now able to dissect the nature of the host–parasite interaction at both the initiation and recall phases of the immune response. Thus the question remains – is the influence of parasites on immunity one that acts primarily in early life, and at initiation of the immune response, or in adulthood and when recall responses occur? In short, parasite immunosuppression – sooner or later
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